阅读说明：本技术 用于压弯玻璃片材的装置和方法 (Device and method for bending glass sheets ) 是由 A·帕尔芒捷 A·蔡希纳 M·N·阿尔廷 L·格亨 于 2021-02-18 设计创作，主要内容包括：本发明涉及一种用于压弯玻璃片材(8)的装置(1),所述装置包括：-第一压弯模具(5),其带有第一压制面(6)；-第二压弯模具(9),其带有第二压制面(10),所述第二压制面包括压制框架(12)和一个或多个压制衬垫(13),其中,压制衬垫(13)分别以支撑物的形式构造并且至少部分地布置在由压制框架(12)包围限界的区域(15)内,其中,压制框架(12)和所述一个或多个压制衬垫(13)分别具有压制面区段(14,14’),所述压制面区段共同地形成第二压制面(10),其中,第二压制面(10)与第一压制面(6)互补地构造,其中,所述两个压弯模具(5,9)能够沿竖直方向相对于彼此如此运动,使得玻璃片材(8)能够在所述两个压制面(6,10)之间被压弯,并且其中,所述一个或多个压制衬垫(13)相应如此构造,使得通过每个压制面区段(14’)能够压弯出带有玻璃片材(8)的交替的弯曲部的区域(B)。(The invention relates to a device (1) for bending glass sheets (8), comprising: -a first press-bending die (5) with a first press face (6); -a second press-bending die (9) having a second press face (10) comprising a press frame (12) and one or more press cushions (13), wherein the press cushions (13) are each configured in the form of a support and are arranged at least partially in a region (15) bounded by the press frame (12), wherein the press frame (12) and the one or more press cushions (13) each have a press-face section (14,14') which jointly form the second press face (10), wherein the second press face (10) is configured complementarily to the first press face (6), wherein the two press-bending dies (5,9) are movable in the vertical direction relative to one another in such a way that a glass sheet (8) can be press-bent between the two press faces (6,10), and wherein the press pad or press pads (13) are designed in such a way that a region (B) with alternating curvature of the glass sheets (8) can be press-bent out by each press surface section (14').)

1. Device (1) for press bending glass sheets (8), comprising:

-a first bending die (5) with a first pressing face (6);

-a second press-bending die (9) with a second press face (10) comprising a press frame (12) and one or more press cushions (13), wherein the press cushions (13) are each configured in the form of a support and are arranged at least partially in a region (15) bounded by the press frame (12), wherein the press frame (12) and the one or more press cushions (13) each have a press face section (14,14') which jointly form the second press face (10), wherein the second press face (10) is configured complementarily to the first press face (6),

wherein the two press-bending dies (5,9) can be moved in the vertical direction relative to one another in such a way that the glass sheet (8) can be press-bent between the two press surfaces (6,10), and

wherein the press pad or press pads (13) are designed in such a way that a region (B) with alternating curvature of the glass sheet (8) can be press-bent out by each press surface section (14').

2. Device (1) according to claim 1, wherein a plurality of press pads (13) are arranged side by side, in particular parallel side by side or obliquely to each other.

3. Device (1) according to claim 2, wherein a plurality of pressing pads (13) are arranged side by side and symmetrically with respect to an axis of symmetry extending between said pressing pads.

4. Device (1) according to one of claims 1 to 3, wherein one or more press pads (13) extend with one end or with both ends respectively into the press frame (12) and possibly with one end or with both ends into corresponding feedthroughs of the press frame (12).

5. Device (1) according to claim 4, wherein the press face section (14') of the press pad (13) is configured in each case such that it transitions continuously into the press face section (14) of the press frame (12).

6. Device (1) according to one of claims 1 to 5, wherein the press face sections (14') of one or more press pads (13) are each of a stepped configuration.

7. The device (1) according to any one of claims 1 to 6, comprising a pretensioning frame (11) for thermally pretensioning a glass sheet (8), wherein the pretensioning frame (11) is laterally movable relative to the first press bending die (5).

8. Device (1) according to one of claims 1 to 7, wherein at least one further first bending die is provided, wherein the further first and second bending dies (9) are movable relative to each other in a vertical direction, so that a glass sheet (8) can be laid on the second bending die (9) and/or can be bent thereon.

9. Method for press bending glass sheets (8), in particular a method which can be performed in an apparatus (1) according to any one of claims 1 to 8, comprising the steps of:

-providing a glass sheet (8) heated to a bending temperature,

-press bending the glass sheet (8) between a first press face (6) of a first press bending mould (5) and a second press face (10) of a second press bending mould (9), wherein the two press bending moulds (5,9) are moved relative to each other in a vertical direction, wherein the second press bending mould (9) comprises a press frame (12) and one or more press pads (13), wherein the press pads (13) are each configured in the form of a support and are arranged at least partially within an area (15) bounded by the press frame (12), wherein the press frame (12) and the one or more press pads (13) each have a press face section (14,14') which jointly form the second press face (10), wherein the second press face (10) is configured complementarily to the first press face (6), wherein a region (B) with alternating curvature of the glass sheets (8) is press-bent by each press face section (14') of the one or more press mats (13).

10. Method according to claim 9, wherein the glass sheet (8) is rested on the second bending mould (9) before pressing between the two bending moulds (5,9), wherein the rested glass sheet (8) is pre-bent by gravity.

11. Method according to claim 10, wherein the glass sheet (8) is fixed at the first press face (6) of the first press-bending mould (5) before resting on the second press-bending mould (9).

12. Method according to claim 11, wherein the second bending mould (9) is transported to a working position associated with the first bending mould (5) during the fixing of the glass sheet (8) at the first press face (6) of the first bending mould (5).

13. Method according to any one of claims 9 to 12, wherein the glass sheet (8) is laid on a pretensioning frame (11) after pressing and thermally pretensioned.

14. Method according to claim 13, wherein the pretensioning frame (11) is transported to a working position associated with the first press bending mould (5) during the fixing of the glass sheet (8) at the first press face (6) of the first press bending mould (5).

15. Use of the device (1) according to any one of claims 1 to 9 and the method according to any one of claims 10 to 14 for the production of glass sheets for vehicles for land, air or water traffic, in particular for motor vehicles, and in particular for roof, rear and side sheets in motor vehicles.

Technical Field

The present invention relates to the technical field of glass sheet manufacturing and to an apparatus and a method for press bending glass sheets and applications thereof.

Background

Glass units for motor vehicles generally have a curved shape. In order to produce the curved structure, the flat glass sheet in the initial state is heated at least to its softening temperature, usually by means of a heating applicator. The glass sheets are then deformed in a single or multistage process. In the industrial mass production of glass sheets, different press bending methods are used, which have already been mentioned many times in the patent literature.

For example, WO 2012/080072 describes a method with stepwise bending of the glass sheets in the edge region and in the inner region. In WO 2004/087590 and WO 2006072721 a method is described in which the glass sheets are first pre-bent by gravity on a press frame and subsequently press-bent by means of an upper and a lower press-bending die. Bending of glass sheets by suction towards the upper press bending mould is described in EP 255422 and US 5906668.

Curved glass sheets can be manufactured in various ways using known press bending methods. In order to ensure a high optical quality of the bent glass sheets, which allows a substantially undistorted perspective, so-called press frames are generally used. Such press frames do not contact the entire glass sheet surface during press bending, but only the peripheral edge region. However, the achievable degree of bending is limited here. In particular, glass sheet shapes having local regions with strong curvatures (small radii of curvature) and/or strong curvature changes (high curvature gradients), which are relatively far from the glass sheet edge, are only difficult to achieve or not at all. This relates in particular to an elongated region with alternating bends, which are also referred to as "edges". Such an edge is aesthetically very attractive.

In order to achieve complex glass sheet shapes, it is advantageous to heat the region concerned locally further in order to ensure a high formability of the glass sheet there. This can be achieved relatively simply in a discontinuous bending method. In such bending methods, which are known, for example, from EP 1358131 a1 and EP 2463247 a1, the glass sheets are usually supported on a transport mould and during the bending process are left in one location for a relatively long time, one or more times, in a heating furnace below. In that case, a desired temperature profile can then be produced on the glass sheet by targeted design of the heating radiators. The complex discontinuous bending method is particularly common for high-value composite sheets, such as wind-shielding sheets.

In addition, however, continuous bending methods exist, which are carried out at a significantly higher cycle time, in particular for individual sheets of safety glass, such as side sheets or rear sheets. The glass sheets are continuously moved through the bending device, in particular on a roller conveyor system, without being left at one point. The method offers glass manufacturers significantly fewer possibilities to influence the heating of the glass sheets and to produce a specific temperature profile. One such bending method is disclosed, for example, in WO 2017/178733 a 1.

US 5974834 a and CN 105502903 a each show a method in which a glass sheet having through-penetrations is bent. In this case, a bending die is used, in which a smaller inner frame is mounted within the outer frame, which inner frame serves for the gravitational bending of the circumferential edge of the feed-through. The hot glass sheet rests for this purpose on the lower bending mould. The internal frame is not used for bending the glass sheets. JPS6424034 shows a method in which two pressing frames in each other and a central support are used. US20110123730 a1 shows a method in which glass sheets are provided with alternating bends in the edge region by two pressing frames lying one inside the other.

Disclosure of Invention

In contrast, the object of the present invention is to provide a press bending method which is improved over the known press bending methods and a corresponding device for press bending glass sheets, with which the production of glass sheets having local regions with strong bends and/or strong curvature changes, in particular in the inner region of the sheet, is achieved, while at the same time achieving a high optical quality. It is important here that the elongated regions of the glass sheets with alternating bends (edges) can be produced with freely selected positioning. Furthermore, the manufacture of such glass sheets should be able to be achieved time and cost efficiently.

The above and further objects are achieved according to the invention by an apparatus and a method for press bending glass sheets having the features of the respective patent claims. Advantageous embodiments of the invention result from the dependent claims.

The device and the method are described in part in common below, with the statements and preferred embodiments relating to the device and the method as such. If preferred features are described in connection with the method, it follows that the device is also preferably designed accordingly and suitable. If the preferred features are described in reverse in connection with the apparatus, it follows that the method is also preferably performed accordingly.

The term "pre-bent" in the sense of the present invention means that the glass sheet is not bent completely with respect to a defined or definable final bend (final geometry or final shape) of the glass sheet. The pre-bending can be, for example, 10 to 80% of the final bending. The term "bending" can relate to pre-bending or final bending.

The glass sheets have edge regions adjoining the edges of the glass sheets at the ends, for example, the edge regions of the glass sheets are surrounded in strips. For example, the strip width is in the range of 3 to 150 mm. The glass sheet edges are formed by (cut) surfaces which are arranged generally perpendicular to the two glass sheet surfaces lying opposite one another. The edge region surrounds a central or inner region which delimits the glass sheets and which directly adjoins the edge region. The glass sheets can be subjected to bending in the edge and/or inner regions. The glass sheets preferably do not have through-openings.

The terms "lateral" or "laterally dislocateable" mean moving with at least one horizontal component of movement by which one component can be arranged laterally relative to the other component.

The apparatus for press bending glass sheets generally comprises a plurality of zones or chambers which can be structurally and functionally separated from one another. One component is a bending zone or bending chamber for press bending the heated glass sheets, which bending zone or bending chamber is advantageously equipped with heating means for heating the glass sheets. In particular, the bending chamber can be brought for this purpose to a temperature which effects plastic deformation of the glass sheets and is typically in the range of 600 ℃ to 750 ℃.

A bending chamber for bending a glass sheet includes a first or upper bending mold having a press face for contacting the glass sheet. For easier reference, the press face of the first press bending die is referred to as the "first press face". The first press surface can be divided in an imaginary manner into an outer surface portion and an inner surface portion. The outer surface section is preferably formed to be suitable for edge bending in the edge region of the glass sheet. The inner surface section is preferably formed to be suitable for surface bending in a central or inner region of the glass sheet, which is surrounded by the edge region. In the operating position, the first press face of the first bending tool is oriented in the direction of gravity, i.e. downward. Preferably, the first press surface of the first press-bending die is designed over the entire surface, wherein the passages can also be provided as suction openings (see below) or the like.

The apparatus for press bending glass sheets includes at least one device for securing the glass sheet at the first press face of the first press bending mold. The device for fixing glass sheets advantageously comprises a pneumatic suction device for sucking a gaseous fluid, in particular air, by means of which the glass sheets can be sucked towards the first press face by means of a negative pressure. The first press surface can for this purpose be provided, for example, with at least one suction opening, advantageously with a multiplicity of suction openings distributed, for example, uniformly over the press surface, where a vacuum can be applied in each case for the suction effect at the first press surface. The suction device can alternatively or additionally have a skirt surrounding the first press face, by means of which skirt an underpressure can be generated at the press face. The suction device generates a generally upwardly directed flow of gaseous fluid, in particular air, sufficient to fix the glass sheet at the first press face. This is achieved in particular by placing a lower bending tool or pretensioning frame below the glass sheets for receiving the glass sheets fixed at the press face.

Alternatively or additionally, the means for fixing the glass sheets advantageously comprise a pneumatic blowing device for generating a flow of gaseous fluid, in particular air, which is configured such that the glass sheets can be blown from below with the flow of gaseous fluid, thereby being lifted and pressed against the first press face of the upper press-bending mould. The blowing device can be designed in particular such that the glass sheets fixed at the first press face are pre-bent by the pressure exerted by the gaseous fluid flow in the edge region and/or in the inner region, advantageously at least in the edge region.

As used herein and further, the term "fixing" relates to fixing the glass sheet at the first pressing face of the first or upper bending mould, wherein the glass sheet can be pressed against and/or sucked to the first pressing face. The fixing of the glass sheets at the first press face is not necessarily associated with the bending process, but generally results in at least a slight bending of the plastically deformable glass sheets.

The first or upper press bending mould is used to fix the glass sheet at the first press face. The first press-bending mould is also used for placing the glass sheets on the lower press-bending mould or on the pretensioning frame or for pressing the glass sheets between the upper press-bending mould and the lower press-bending mould.

The apparatus for bending glass sheets also includes a second or lower bending mold with a pressing surface for supporting the glass sheet, pressing the glass sheet in cooperation with the first bending mold, and optionally also for transporting the glass sheet. For easier reference, the press face of the second press bending die is referred to as the "second press face". In the operating position, the second press face of the second press-bending tool is oriented against the direction of gravity, i.e. upward.

As used herein and in addition, the terms "upper bending die" and "lower bending die" relate to two different bending dies, wherein the upper bending die is arranged above the lower bending die in the working position for pressing the glass sheet.

According to the invention, the second bending tool has a press frame. The press frame is constructed in the form of a frame without or with through-openings. The press frame encloses an (inner) area bounding the second press bending die. The press frame of the second press bending mould has a press face (i.e. a press face section of the second press face) which is configured to be suitable for bending the glass sheet (only) in the edge region of the glass sheet. The region of the glass sheet which is in contact with the press face of the press frame is usually a peripheral (for example strip-shaped) edge region of the glass sheet which surrounds it, wherein the glass sheet can however also project beyond the press face of the press frame. The press face of the press frame is configured, for example, in the form of a strip, for example with a strip width in the range of 3 to 150 mm. It goes without saying that a larger width is advantageous in terms of avoiding undesirable markings (variations in the flat surface of the glass sheet) due to a better weight distribution, wherein the production of markings can be counteracted by pressing the glass sheet in the edge region. The frame is usually designed in such a way that a (e.g. strip-shaped) circumferential edge region of the glass sheet can be bent by the press face of the frame. The press frame is also "circumferentially" configured in correspondence with the circumferential edge region of the glass sheets. The frame can have one or more interruptions, wherein the circumferential edge region of the glass sheet cannot be bent by the press frame at the frame interruption in this case. The press frame is a closed structure, wherein the press frame is adapted in terms of its shape to the surrounding edge region of the glass sheet and thus to the outer contour of the glass sheet. The press frame can also be called "toroidal", with the following description: the press frame can have any arbitrary shape which is adapted to the outer contour of the glass sheets, which shape usually differs from a circular ring shape.

The second press-bending tool effects a surface bending by gravity in the inner region of the glass sheet enclosed by the edge region and is designed for this purpose in such a way that the inner region of the glass sheet can sag by gravity in the region of the second press-bending tool enclosed by the press frame. For this purpose, the second press-bending tool can be open, i.e. provided with a central passage, which is surrounded by the press frame. Alternatively, the second press-bending tool can also be constructed over the entire surface area, provided that the sagging of the inner region of the glass sheet is achieved. The open design is preferred for easier processing of the glass sheets. When gravity bends, the glass sheet bends due to its own weight.

The second press bending die also has one or more press elements (also referred to as "press pads") configured for press bending the glass sheets. If in the further description a plurality of press cushions is mentioned, these statements also always relate to the case in which the second bending die has only a single press cushion, as long as a plurality of press cushions is not absolutely necessary.

The press linings are each arranged at least in sections (i.e. partially) in the region bounded by the press frame. The press pad can be located entirely within the area bounded by the press frame enclosure. However, it is also possible to extend the press blanket with one or both ends into the press frame (i.e. into corresponding interruptions of the press frame) and to supplement the press frame with a closed structure without through openings.

Both the press frame and the press pad each have a press face section for pressing the glass sheet in cooperation with the first press face of the first press bending tool. The press face section of the press frame and the press pad together form a second press face of the second press bending die. The second bending die without the press pad can also be referred to as a press frame (e.g., press ring).

The first press-bending tool for pressing glass sheets has a first press-forming face which is configured complementarily to a second press-forming face of the second press-bending tool. By "complementary" is meant that the first press surface of the first press-bending tool is configured as a negative tool with respect to the second press surface, which is then a positive tool.

The first and second press-bending dies can be vertically offset relative to each other so that the glass sheet can be press-bent between the two press faces. The glass sheet is thus bent in the edge region and in the inner region enclosed by the edge region. Furthermore, when the glass sheet is supported on the second bending mould, the bending of the glass sheet can then be achieved by gravity in the edge region and the inner region. The term "press-bending mould" does not exclude the possibility that the glass sheet is additionally subjected to gravity bending on the second press-bending mould. In the device according to the invention, the bending of the glass sheet always takes place by means of the two bending moulds. For example, the glass sheet is first placed on a lower bending mold and then pressed between the two bending molds, or the glass sheet is pressed between the two bending molds without previously placing the glass sheet on a second bending mold.

The press pads each have an elongated shape and are constructed in the form of a support. The press-on lining is not supplemented here by the closed structure and does not form the frame. In particular, the press-on pad does not serve to bend the glass sheets in the region of the circumferential edge of the feed-through.

The one or more press mats are each designed in such a way that an elongate region with alternating bends in the glass sheets can be press-bent out by each press surface section of the press mat. In other words, only one region with alternating bends of the glass sheets can be produced per press pad. Accordingly, a plurality of regions with alternating bends in the glass sheets can be produced by a plurality of press pads. Each area with alternating bends (corresponding to the arrangement of the press cushions) is produced by the press cushions by bending between the two bending moulds and, if appropriate, by gravity bending on the second bending mould, at least in the inner area of the glass sheet, which is not in direct contact with the press frame. By applying the press mats to the glass sheets, in each case one region with alternating bends can be produced by a combination of gravity bending and pressing or alternatively only by pressing in the inner region and optionally the edge region of the glass sheets.

The regions of the glass sheet with alternating bends can also be referred to as "edges" and can be regarded as a combination or series of convex and concave bends of the glass sheet. The convex curvature is a convex portion of the glass sheet, and the concave curvature is a concave portion of the glass sheet. At the depressions of the glass sheet, the glass sheet deepens, for example, against the direction of gravity, i.e. in the direction of the first bending tool. At the projections, the glass sheets deepen, for example, in the direction of gravity, i.e. in the direction of the lower bending tool. The sequence of convex and concave bends is transverse to the extent of the elongate region with alternating bends (edges).

Each of the two bending tools has a pressing surface which is in contact with the glass sheet and acts on the glass sheet for shaping in order to adapt the glass sheet to the shape of the pressing surface and thereby bend the glass sheet. The press face is thus adapted to influence the shape of the glass sheet. The press face can also be referred to as a contact face or in general as an "active face". The press face determines the shape of the bent glass sheet. The press face can be in direct contact with the glass sheet. However, the press surface can also be provided, for example, with a fabric, which is arranged between the original press surface and the glass sheet.

The press face generally has a defined geometry, wherein the bending die is sufficiently rigid for this purpose. The circumferential press frame and the at least one press pad are formed, for example, as a cast part. The press face is produced, for example, by milling.

The first press face of the first or upper press-bending tool is generally of full-surface design. The full-area press face can also be referred to as solid and is in contact with a large portion of the glass sheet face at the end of the bending step. The full-area press face can be provided with holes or openings through which a suction effect can be applied to the surface of the glass sheet facing the press face.

The second press face of the second or lower press brake is formed by the press frame and the one or more press linings. The press bending die of the lower portion without the press pad can also be referred to as a press frame. The frame can also be provided only for supporting the glass sheets (i.e. not for press bending). An example of this is a pre-tensioned frame (see below).

The press surfaces of the press brake can be of planar, convex and/or concave design. A concave shape is understood to mean a shape in which the corners and edges of the glass sheet are bent away from the press bending tool with a defined contact with the press surface. A convex shape is understood in turn to be a shape in which the corners and edges of the glass sheet are bent in the direction of the press bending tool with a defined contact with the press face. The substantially concave press surface can additionally have a convex region, and the substantially convex press surface can additionally have a concave region.

The glass sheets are generally transported horizontally through the bending device. A lower bending tool in the sense of the present invention is understood to be a tool which touches or is associated with and acts on a lower (ground-facing) surface of the glass sheet. An upper press-bending tool is understood to mean a tool which is associated with and acts on the upper (surface facing away from the ground) surface of the glass sheet. The glass sheets are blown and/or sucked from the conveying device onto the press surfaces of the upper bending tools or are pressed with tools, for example, lower bending tools, onto the upper bending tools. The upper press bending tool can be mounted in a stationary position or can be lowered for receiving or pressing the glass sheets.

Usually, only a part of the press face comes into contact with the glass sheet at the beginning of the bending step and the glass sheet comes to bear against the press face during the progression of the bending step. This can be achieved under the action of gravity, pressing pressure or suction.

The device for bending glass sheets comprises an upper bending mould and a lower bending mould between which the glass sheets can be bent. The upper press-bending die preferably has a full-area press face. The lower press-bending tool has a press face with a frame-like press-face section for the edge region of the glass sheet and a press-face section provided by at least one press pad for the inner region and optionally the edge region of the glass sheet. In an advantageous embodiment, the glass sheets are blown and/or sucked onto the press surfaces of the upper press-bending tool. The device further comprises means for moving the lower and upper bending tools towards one another, such as cylinders, actuating motors, chain-pulling systems or robot arms, by means of which the upper bending tool can be lowered and/or the lower bending tool can be raised. For example, the first or upper bending tool is coupled to a movement mechanism by means of which the first bending tool of the second or lower bending tool can be advanced. However, it is also possible to feed the second or lower bending tool relative to the first or upper bending tool.

The device according to the invention for press bending glass sheets advantageously enables the production of glass sheets with partial regions which each have alternating bends. These regions have a generally small radius of curvature and/or a strong change in curvature (high curvature gradient) and can advantageously also be relatively far from the edge of the glass sheet (i.e. in the inner region of the glass sheet). This is achieved by one or more press pads of the second press brake die, which are each configured in such a way that they are suitable for producing an elongated region (edge) with alternating bends. The press linings are each arranged at least partially within the press frame, i.e. within the region of the second press-bending tool which is bounded by the surrounding press frame and in which the gravity bending of the glass sheets is effected. The use of press mats thus advantageously enables the production of glass sheets with very complex geometries, in which strongly curved edges are present in the inner region of the glass sheets with high optical quality.

According to an advantageous embodiment of the device according to the invention for bending glass sheets, the lower bending tool has a plurality of press linings, so that a plurality of partial regions with alternating bends (edges) can be produced. As already explained, the press-on lining is not added to the (e.g. closed) frame in order to bend the glass sheets in the circumferential edge region of the feed-through.

According to an advantageous embodiment of the device according to the invention, the press pad or the press pads are each located completely within the region bounded by the press frame. In this case, the edge can only be produced in the inner region of the glass sheet.

According to a further advantageous embodiment of the device according to the invention, one or more press cushions each extend with one end or with both ends to the press frame. This advantageously enables the edge to be produced which extends to the edge region of the glass sheet. It is also possible for one or more press cushions to each extend with one or both ends into a corresponding interruption of the press frame. In this case, it is particularly advantageous if the press surface section (i.e. the contour of the press surface) of the respective press pad is continuously guided further into the press surface (i.e. the contour of the press surface) of the press frame (either by the press pad or by the press frame itself), so that the edge can also be continuously guided further into the edge region of the glass sheet.

According to a further advantageous embodiment of the device according to the invention, the press mats are arranged side by side, in particular parallel to one another or at an angle to one another. Particularly advantageously, a plurality of press pads are arranged side by side and symmetrically with respect to an (imaginary) symmetry axis extending between the press pads. The axis of symmetry does not intersect the press pad here, but the press pads are arranged on both sides of the axis of symmetry. As a result, particularly aesthetically appealing edges can be produced in the glass sheets, which are used, for example, as sunroofs, backlights or sidelights of motor vehicles.

For example, the press pad is arranged in such a way that the resulting edge of the glass sheet extends in the longitudinal direction (height direction) or is positioned at an angle to the longitudinal direction. For example, the press pad is arranged in such a way that the resulting edge extends in the transverse direction of the glass sheet or is disposed at an angle to said transverse direction. The longitudinal direction of the glass sheets corresponds, for example, to the direction of movement of the vehicle. The transverse direction of the glass sheet is the direction perpendicular to this direction of movement.

According to a further advantageous embodiment of the device according to the invention for press bending glass sheets, the press surface sections of the press mats are each designed in a stepped manner. By "stepped configuration" is meant that a pressed face section comprises a region with alternating bends. This allows a particularly simple production of the edge in the inner region of the glass sheet, which is very aesthetically attractive.

The press mats can in principle be designed as desired, provided that it is ensured that the press surface sections provided by each press mat effect the press bending of the glass sheets with the first press bending tool for producing the region with alternating bends (edges) of the glass sheets. In order to avoid optical errors, in particular in the inner region of the glass sheets, it can be advantageous if the press pad has a core with a jacket portion, wherein the jacket portion is more saggy, i.e. softer, than the core. This measure advantageously makes it possible for the glass sheet to be "softer" to some extent in order to rest against the second press face, as a result of which the optical error frequency is less frequent. The jacket part is made of a material which is subjected to high temperatures during bending. Preferably, the mantle section is made of a knitted fabric (eyelet knit) comprising, for example, steel fibers and glass fibers. Such mantle sections are known to those skilled in the art from professional trading.

According to a further advantageous embodiment of the device according to the invention for bending glass sheets, the bending zone comprises at least one further first or upper bending mould with a first press face for the glass sheets. The additional first press bending mould does not necessarily have to be used for pressing glass sheets with a second press bending mould. It is conceivable that the further first bending tool is used only for fixing the glass sheet at the first press face of the further first bending tool and for placing it on the second bending tool.

The at least one further first and second bending die can be moved in the vertical direction relative to each other, so that the glass sheet can rest on the second bending die and/or can be bent. Preferably, the second bending die is movable laterally (i.e. with at least one horizontal movement component) relative to the first bending die between the operating positions associated with the two first bending dies. Advantageously, the lower press bending dies are capable of mutual and translational (one-dimensional) movement in a horizontal plane. In general, the working position of the second bending tool associated with the respective first bending tool is located vertically (for example directly) below the first bending tool.

Advantageously, the apparatus according to the invention also has a preheating zone or chamber with heating means for heating the glass sheets to the bending temperature, and a transport mechanism (of the type, in particular a roller bed) for transporting the glass sheets from the preheating zone to the bending zone or chamber, in particular to a removal position (for example directly) below the first bending mould. The roller bed is advantageously configured such that a plurality of individual glass sheets can be transported in succession to the removal position. The removal position can in particular correspond to an end section of the roller bed.

Advantageously, the device according to the invention also has a hot pre-tensioning region with a cooling device for the hot pre-tensioning of the glass sheets, wherein a pre-tensioning frame (for example a pre-tensioning ring) is provided for transporting the glass sheets. Preferably, the pretensioning frame is laterally movable (i.e. with at least one horizontal movement component) in a mutual manner relative to the first bending die between the two working positions. Advantageously, the pretensioning frames are capable of mutual and translational (one-dimensional) movement in a horizontal plane.

By thermal pre-tensioning (annealing), a temperature difference between the surface region and the core region of the glass sheet is produced in a targeted manner in order to increase the fracture resistance of the glass sheet. The pretensioning of the glass sheets is advantageously generated by means of a device for blowing the glass sheets with a gaseous fluid, preferably air. Preferably, both surfaces of the glass sheet are simultaneously subjected to a cooling air flow.

Advantageously, the pretensioning frame for transporting the glass sheet from the bending zone to the pretensioning zone has a frame face configured for edge bending in an edge region of the glass sheet. Furthermore, it is advantageous if the pretensioning frame is configured to be suitable for surface bending in the inner region of the glass sheet by gravity. The pretensioning frame has only one frame, but no bending element in the inner region bounded by the frame enclosure. In particular, the pretensioning frame has no press-on pad.

The device for press bending glass sheets according to the invention advantageously comprises at least one, in particular a plurality of, heating means for heating the glass sheets to be bent. The heating means are preferably adapted to substantially uniformly heat the glass sheets, as is also common in conventional bending devices. Uniform heating is understood to be heating in which the entire main surface of the glass sheet is exposed to substantially the same temperature without a significant temperature profile. However, it is also possible for the glass sheet to be heated more intensively where particularly strong bends occur. The glass sheet to be bent is generally flat in the initial state.

The heating means preferably act substantially uniformly and over the entire area at least on both main surfaces of the glass sheet, in particular by thermal radiation or convection. In particular, the heating means are heating means like those also used in conventional bending devices. The heating means can be designed, for example, according to the type of convection furnace, wherein a heating chamber is supplied with heated air, whereby heating of the glass sheets is effected in the heating chamber. Usually, the heating device is configured as a heating radiator. In this case, at least one heating radiator, in particular a plurality of heating radiators, which are associated with and face a main surface of the glass sheet, and also at least one heating radiator, in particular a plurality of heating radiators, which are associated with and face a further main surface, are preferred. The main surfaces are subjected to thermal radiation by means of their associated heating radiators facing said main surfaces, as a result of which the glass sheets are heated. The glass sheets are advantageously transported horizontally on a transport device into a heating chamber, where heating radiators are arranged below and above the transport device in order to act on the two main surfaces.

The device according to the invention is preferably equipped with transport means for transporting the glass sheets. The transport means are used to transport the glass sheets to be bent to the heating means and to the bending mould. In a preferred embodiment, the transport means is designed as a roller or belt conveyor system on which the glass sheets are supported directly and on which they are moved horizontally lying. This enables a particularly short cycle time. Alternatively, however, the glass sheets can also be supported on a transport mold, in particular a mold with a frame-like support surface, which is itself moved, for example, by means of a roller conveyor system, a belt conveyor system or a rail conveyor system.

In a preferred embodiment, the transport means is designed as a continuous transport system, particularly preferably as a continuous roller transport system. In such a conveying system, the glass sheets are continuously moved through the apparatus toward the bending mold without a longer dwell time at one location. The glass sheets are supplied to the heating means and the bending mould in a continuous movement by means of a continuous conveying system. The glass sheets are heated during the continuous movement by means of heating means. The heating means, in particular heating radiators, are preferably arranged above and below the rollers of the roller conveyor system and are directed towards the roller conveyor system, so that they act simultaneously on both main surfaces of the glass sheet, thereby achieving an efficient heating of the glass sheet. Continuous roller conveying systems are commonly used, in particular, in the bending of single-pane safety glass, which is relatively cost-effective, for example for side, roof or rear panes of vehicles. The conveying speed of the continuous conveying system is preferably 100mm/s to 600 mm/s. The invention can, however, in principle also be used for discontinuous bending devices in which the movement of the glass sheets is interrupted and the glass sheets stay for a longer time at one point or move back and forth, in particular in order to be heated by means of heating means. Instead of a continuous roller conveyor system, a continuous belt conveyor system can also be used. The conveying system can also be designed completely or in sections as an air mattress conveying system.

The glass sheets are preferably heated by heating means to a temperature of from 500 ℃ to 700 ℃, particularly preferably from 550 ℃ to 670 ℃, for example about 650 ℃. This corresponds to the typical bending temperature for glass sheets, in particular for glass sheets made of soda-lime glass.

In one embodiment of the invention, the heating device is arranged in a heating chamber and the bending tool is arranged in a bending chamber. The heating chamber and the bending chamber are separated from each other and are each (to the greatest extent) closed off from the surroundings by a chamber wall. The transport means pass through the heating chamber and are guided into or through the bending chamber. The glass sheets are transported into the heating chamber and out of the heating chamber again by means of a transport device. Preferably, the input and output of the heating chamber are located at opposite sides to each other, so that the glass sheets are transported through the heating chamber by means of the transport device. The glass sheet is then transported into a bending chamber and transferred to a first bending mold. The glass sheets can be rested on the transport means again after the press bending in order to transport the glass sheets out of the bending chamber or otherwise out of the bending chamber. The heating chamber and the bending chamber have openings for the transport of the glass sheets. At least in the heating chamber, the openings are preferably embodied in the form of slots with a height that is as small as possible in order to prevent intensive cooling of the chamber. When no glass sheet is being transported through the opening, the opening can optionally be closed with a sliding door system or a drapery system.

In a further embodiment of the invention, the heating device and the bending die are arranged in a common chamber, which can be referred to as a combined heating and bending chamber. The combined heating and bending chamber is (to the greatest extent) closed off from the surroundings by the chamber walls. The transport means are guided into or through the heating and bending chamber. The glass sheets are transported into the heating and bending chamber by means of transport means. Where the glass sheets are first exposed to the action of a heating device and then transferred to a bending mould. The glass sheets can be rested on the transport means again after the press bending in order to transport them out of the heating and bending chamber or to transport them out of the heating and bending chamber in another way. The heating and bending chamber has an opening for the transport of the glass sheets. When no glass sheet is being transported through the opening, the opening can optionally be closed with a sliding door system or a drapery system.

In a particularly preferred embodiment, the transport means is designed as a continuous roller conveyor system. The heating means are designed as heating radiators which are arranged above and below the roller in the heating chamber or the combined heating and bending chamber. The glass sheets are continuously moved between the heating radiators by means of a roller conveyor system and are fed to an upper bending tool with a preferably full-area press surface, which is arranged above the rollers either in the own bending chamber or in a combined heating and bending chamber. If the glass sheets are positioned below the upper bending mould, the glass sheets are blown (from below by an air flow) and/or sucked to the upper bending mould. The lower press bending mold is then moved under the upper press bending mold with the glass sheet and presses the glass sheet between the upper press bending mold and the lower press bending mold to bend the glass sheet to the desired shape. The lower bending die is then removed again during the fixing of the glass sheets at the upper bending die by blowing and/or suction as before. The pretensioning frame is now moved under the press bending mould with the upper part of the glass sheet and the glass sheet is transferred to the pretensioning frame by the cutting blowing or suction effect. The glass sheets are removed from the bending chamber or the combined heating and bending chamber on the prestressing frame and fed to the prestressing device, where they are subjected to an air flow and are thereby cooled and thermally prestressed.

In a preferred embodiment, the glass sheets to be bent consist of soda lime glass, as is common for window sheets. The glass sheet to be bent can also comprise other glass types, such as borosilicate glass or quartz glass. The thickness of the glass sheet is generally from 0.2mm to 10mm, preferably from 0.5mm to 5 mm. In a preferred embodiment, the bent glass sheet is provided as a window sheet for a vehicle, in particular as a side, top or rear sheet for a motor vehicle.

The device according to the invention for press bending glass sheets is used in particular for carrying out the method described in this way. In this regard, reference is made fully to the foregoing specification.

The method according to the invention comprises a step in which a glass sheet heated to a bending temperature is provided. The method can comprise a step in which the glass sheet is heated substantially uniformly by the heating means. The glass sheet is brought to at least its softening temperature, at which the glass is brought into a formable state. However, it is also possible for the glass sheet to be heated more intensively where particularly strong bends should occur.

The method according to the invention comprises a further step in which the glass sheet heated to the bending temperature is pressed between the first press face of the first bending mould and the second press face of the second bending mould. Reference is made to the above explanations with regard to the design of the two bending tools. The glass sheet is pressed between a first press surface and a second press surface, wherein the two press bending tools are moved relative to one another in the vertical direction. The second press-bending die comprises a press frame and one or more press cushions, wherein the press cushions are each configured in the form of a carrier and are arranged at least partially in the region bounded by the press frame. The press frame and the one or more press mats each have a press surface section which jointly forms a second press surface, wherein the second press surface is configured complementarily to the first press surface, wherein the regions with alternating bends (edges) of the glass sheet are press-bent out by each press surface section of the one or more press mats.

According to one embodiment of the method according to the invention, the method comprises a further step in which the glass sheet is fixed to the first press face of the first bending tool. Advantageously, the fixing of the glass sheet at the first pressing face of the first bending mould is achieved by lifting the glass sheet and pressing it against the first pressing face of the first bending mould by blowing with a gaseous fluid. Alternatively and preferably additionally, the glass sheets are fixed by suction at the first press face of the first bending mould. Depending on the pressure with which the glass sheet is pressed against the first pressing face of the first bending die, the glass sheet can be subjected to an edge pre-bending in the edge region and/or a face pre-bending in the inner region.

The glass sheet fixed at the first bending mould can be pressed between the first and second bending moulds without previously resting on the second bending mould.

According to a particularly advantageous embodiment of the method according to the invention, the method comprises a further step in which the glass sheet is placed on a second bending tool before being pressed between the two bending tools, wherein the placed glass sheet is pre-bent only by gravity. The glass sheet is fixed for this purpose at the first press face of the first bending tool or of a further first bending tool and is then laid down by the first bending tool on the second bending tool. The glass sheet is then pressed between a first press bending die and a second press bending die. By previously resting on the second press bending mould, the glass sheet is pre-bent by gravity and subsequently bent by pressing, so that the glass sheet is bent stepwise and protectively, whereby the probability for optical errors can be reduced and the optical quality of the glass sheet can be further improved.

According to an advantageous embodiment of the method according to the invention, the second bending tool is transported into the operating position associated with the first bending tool during the fixing of the glass sheet on the first press side of the first bending tool. If two first bending moulds are used, it can be advantageous to transport the glass sheet on the second bending mould from one first bending mould to the other, wherein the pre-bending of the glass sheet takes place by gravity during the transport. However, it is also possible to keep the second bending tool stationary (unchanged in position) together with the supported glass sheet and to move the two first bending tools laterally toward the second bending tool.

According to a further embodiment of the method according to the invention, the method comprises a further step in which the glass sheets are transported on the pre-tensioning frame to a cooling device for thermally pre-tensioning the glass sheets. Preferably, the pretensioning frame is transported to a working position associated with the first bending mould during the fixing of the glass sheet at the first press face of the first bending mould. Advantageously, the pretensioning frame is moved laterally relative to the first press-bending die between an operating position associated with the first press-bending die, which is preferably located (for example directly) below the first press-bending die, and a further operating position for thermally pretensioning the glass sheets. Preferably, the pretensioning frame is moved in a horizontal plane between said two working positions in a (bi-directional) translation (one-dimensional) relative to each other.

The pressing of the glass sheet between the two bending dies can give the glass sheet a final or near final shape. Usually, but not necessarily, the shape of the glass sheets is also (in each case only slightly) changed on the pretensioning frame. The glass sheets then acquire their final shape on the pretensioning frame.

Preferably, the glass sheet is transported by a transport mechanism (of the type, in particular, a roller bed) up to a removal position, which is preferably located (for example directly) below the first bending die. Preferably, the glass sheets are heated to a bending temperature on a roller bed.

The invention is particularly suitable for press bending glass sheets, in particular in the inner region of the glass sheets, with complex bends (edges) which can only be produced with difficulty by conventional methods. Such complex curvatures can be characterized, for example, by regions with particularly small radii of curvature or with strong curvature changes.

The invention also extends to the use of the device according to the invention and the method according to the invention for producing glass sheets for vehicles for land, air or water traffic, in particular for motor vehicles, and in particular for side, top and rear sheets in motor vehicles.

The different embodiments of the invention can be implemented individually or in any combination. In particular, the features mentioned above and explained below can be used not only in the combination indicated, but also in other combinations or alone without leaving the scope of the invention.

Drawings

The invention will now be explained in detail by way of examples, wherein reference is made to the accompanying drawings. Which is shown in simplified, not-to-scale illustration:

figure 1 shows a cross section of a design of the device according to the invention during a first part of the method according to the invention,

figure 2 shows a cross-section of the device of figure 1 during a second part of the method according to the invention following the first part,

figure 3 shows an embodiment of the press bending mould for the lower part in a perspective view,

figure 4 shows a cross-section of the lower press bending die of figure 3,

figure 5 shows a cross section of a glass sheet bent according to the invention,

fig. 6 shows a flow diagram of a method for manufacturing a glass sheet according to the invention.

Detailed Description

Fig. 1 is first of all observed, in which a device for press bending glass sheets, generally designated by reference numeral 1, is shown in a schematic manner at later points in time. The device 1 comprises a heating chamber 2 in which a heating means 3 is arranged, which is designed here, for example, as a heating radiator. Furthermore, the device 1 comprises a bending chamber 4, into which an upper bending die 5 is inserted. The upper press brake 5 has a convex press surface 6 of full area, referred to herein as the upper press surface 6. The upper press surface 6 is arranged on the underside of the upper press-bending die 5 and points downward in the operating position.

Furthermore, the device 1 comprises a roller conveyor system 7 which extends through the heating chamber 2 and into the bending chamber 4. In the illustration of fig. 1, the heating chamber 2 is spaced apart from the bending chamber 4, wherein it goes without saying that the heating chamber 2 can directly adjoin the bending chamber 4. In the initial state, the flat glass sheets 8 are positioned directly on the roller conveyor system 7 and are moved in a continuous movement (from the left in the drawing) into the heating chamber 2, through the latter and then into the bending chamber 4. In the heating chamber 2, the glass sheets 8 are heated here substantially uniformly by the heating means 3, for example to a temperature of about 650 ℃ (fig. 1 a). The heating means 3 are arranged in the heating chamber 2 above and below the roller conveyor system 7 in order to irradiate both surfaces of the glass sheets 8 simultaneously.

The device 1 is designed for a continuous bending process. When the previous glass sheet 8 arrives in the bending chamber 4, the device is already able to transport the next glass sheet 8 to be bent into the heating chamber, but this is not shown for the sake of simplicity. The distance between successive glass sheets 8 depends in particular on the takt time of the bending in the bending chamber 4.

Fig. 1a shows a situation in which the glass sheets 8 are located in the heating chamber 2 on the roller conveyor system 7. In fig. 1b, the glass sheets 8 to be heated to the bending temperature are transported from the heating chamber 2 to the bending chamber 4 on a roller conveyor system 7. In fig. 1c, the glass sheet 8 heated to the bending temperature is located in the bending chamber 4 on the roller conveyor system 7.

Continuing with fig. 1, fig. 2 shows the device 1 from fig. 1 during a second part of the method, respectively at later points in time. The glass sheets 8 are blown onto the upper press-bending mould 5 by an air flow (not shown) passing from below through the rollers of the roller conveyor system 7, which is supported via a suction effect through openings in the upper press face 6 of the upper press-bending mould 5 (fig. 2 a).

The lower press-bending mould 9 is now moved below the upper press-bending mould 5, for example by means of a chain-pulling system or a movable cylinder, and the glass sheet 8 is pressed between the two press-bending moulds 5,9 (fig. 2 b). For this purpose, the upper press-bending mould 5 is lowered onto the lower press-bending mould 9 with the glass sheet 8. The lower press brake 9 has a concave (second) pressing surface 10 which is complementary to the convex (first) pressing surface 6 of the upper press brake 5. The glass sheet 8 is bent into the desired shape by pressing between the two press bending dies 5, 9.

The lower press-bending tool 9 is then removed again and the pretensioning frame 11 with the frame-like bearing surface is moved under the glass sheet 8. By interrupting the blowing and suction action, the glass sheet 8 is released from the upper bending mould 5 and rests on the pretensioning frame 11 (fig. 2 c). The glass sheet 8 is then removed from the bending chamber together with the prestressing frame 11 and fed to a prestressing device (not shown) where it is thermally prestressed by rapid cooling by means of a strong gas flow, in particular an air flow.

Fig. 3 shows an exemplary embodiment of a lower bending die 9 of the device 1 according to the invention in a perspective view from above. The lower bending tool 9 comprises a closed (non-through) press frame 12 which encloses an open region (interior) 15. Two press pads (pads) 13 are arranged within the press frame 12, i.e. in the area 15 bounded by the press frame 12. The press pads 13 each have an elongated shape and are configured as supports. The two press pads 13 are arranged side by side, in parallel. The (second) press face 10 of the lower press-bending tool 9 is formed by the press face sections 14 of the press frame 12 and the press face sections 14' of the two press mats 13.

In the exemplary embodiment of fig. 3, the two press linings 13 do not extend to the press frame 12, but it is also possible for the two press linings to each extend with one end or with both ends to the press frame 12. The press pad 13 is arranged here, for example, completely in the region 15 delimited by the press frame 12. It is possible for the press frame 12 to have one or more passages. One or more press linings 13 can each extend with one or both ends into the passage of the press frame 12, so that they are each arranged with one section in the region 15 bounded by the press frame 12 and with one or both end sections in the region of the press frame 12. Instead of two press pads 13, a larger or smaller number of press pads 13 may be provided. In this embodiment, the two press pads 13 are arranged symmetrically with respect to a (imaginary) symmetry line. The two press pads 13 in this case extend, for example, in each case in the longitudinal direction of the glass sheet 8, wherein the two press pads can likewise be arranged obliquely to the longitudinal direction, or can extend in each case in the transverse direction of the glass sheet 8 or can be arranged obliquely to the transverse direction.

Fig. 4 shows the upper and lower bending tools 5,9 in a pressing position in which the (first) pressing surfaces 6,10 of the upper and lower bending tools 5,9 rest against one another. During pressing, the glass sheet 8 is located between the two press faces 6,10, which is not shown in fig. 4. It can clearly be seen that the (first) pressing surface 6 of the upper press brake 5 is configured complementarily to the (second) pressing surface 10 of the lower press brake 9, in particular in the region of the press pad 13. The press face sections 14' of the press pad 13 are each provided with a step 16 which extends in the direction of extension of the press pad 13. In an alternative embodiment, in which the press linings 13 each extend into the press frame 12, it is conceivable for the press face section 14 of the press frame 12 to have precisely the step 16, in which the shape of the press face section 14' transitions continuously into the press face section 14. Alternatively, the press pad 13 may extend into the press frame 12.

Fig. 5 shows an exemplary glass sheet 8 with a complex curvature, which can be produced with the device according to the invention and the method according to the invention. The glass pane 8 has two regions B in an inner region 18 bounded by an edge region 19, which are strongly curved and which are furthermore characterized by a strong curvature change, i.e. alternating curvature. Between the two regions B there is a recess 17 of the glass sheet 8. Outside the region B, the glass pane 8 is bent less strongly with a radius of curvature as is usual for vehicle glazing. Since the region B extends over the see-through region of the glass sheet 8 and is thus not contacted by the press frame 12 of the lower press-bending die 9, complex shapes are only difficult to produce with conventional methods. This shape can be achieved by the lower press-bending die 9 over the entire area, but this significantly reduces the optical quality of the glass sheet 8. The recess 17 can be formed in the inner region 18 of the glass pane 8, but also extends as far as into the edge region 19.

In fig. 6, the steps of the method for producing the glass sheets 8 are shown step by step according to a flow diagram. Here, in a first step I a glass sheet 8 is provided which is heated to a bending temperature. In a second step II, the glass sheet 8 is fixed against the (first) press face 6 of the first press-bending mold 5, with edge pre-bending if possible in the edge region 19 and face pre-bending if possible in the inner region 18 of the glass sheet 8. In a third step III, the glass sheet 8 is pressed against the (second) pressing face 10 of the lower press-bending mould 9, whereby the depression 17 is created.

In an optional further step, the glass pane 8 is placed on a pretensioning frame 11 and thermally pretensioned, wherein gravity bending can occur during transport to the pretensioning chamber. The glass pane 8 thus only assumes its final shape on the pretensioning frame 11.

In the exemplary embodiment of the method according to the invention, which is illustrated in the figures, the glass sheet 8 is bent by pressing the glass sheet 8 between the first bending die 5 and the second bending die 9, wherein the depressions 17 are produced. It is also possible to first place the glass sheet 8 on the lower bending mould 9, so that it is subjected to gravity bending, and then press between the upper bending mould 5 and the lower bending mould 9. The optical quality can be further improved by this gradual bending of the glass sheets 8.

As is apparent from the above description, the invention provides a method and a device for producing glass sheets, by means of which simple, reliable and cost-effective production of glass sheets with short cycle times is achieved. Glass sheets with strongly curved regions with alternating bends (edges) in the inner and edge regions can be produced with high quality requirements. Furthermore, the throughput can be increased in the case of complex glass designs.

List of reference numerals

1 apparatus

2 heating chamber

3 heating device

4 bending chamber

5 first bending die

6 first press face

7 roller conveying system

8 glass sheet

9 second bending die

10 second press face

11 Pre-tensioning frame

12 pressing frame

13 pressing pad

14,14' press area section

15 area

16 step part

17 recessed part

18 inner region

19 edge region