阅读说明：本技术 用于将盖可枢转地紧固到家具本体的盖配件 (Cover fitting for pivotably securing a cover to a furniture body ) 是由 A·本代菲 于 2020-03-13 设计创作，主要内容包括：本发明涉及一种用于将盖(11)可枢转地紧固到家具本体(6)处的盖配件(1),其中,盖配件(1)具有：用于使盖(11)运动的调整元件(8)；至少一个弹簧元件(14),布置成在调整元件(8)和支座(15)之间被加载预紧力,以对调整元件(8)力加载；以及调节元件(19),其具有螺纹(20),螺纹和支座(15)的配合螺纹(21)啮合,其中,支座(15)可通过围绕纵轴线(L)使调节元件(19)转动来沿纵轴线(L)的方向调节,并且当达到至少一个终点位置时与止挡件邻抵,其中,调节元件(19)通过转矩限制结构(36)与控制元件(23)驱动连接。(The invention relates to a cover fitting (1) for pivotably fastening a cover (11) to a furniture body (6), wherein the cover fitting (1) has: an adjusting element (8) for moving the cover (11); at least one spring element (14) which is arranged to be subjected to a pretensioning force between the adjusting element (8) and the abutment (15) in order to force-load the adjusting element (8); and an adjusting element (19) having a thread (20) which engages with a mating thread (21) of the bearing (15), wherein the bearing (15) can be adjusted in the direction of the longitudinal axis (L) by rotating the adjusting element (19) about the longitudinal axis (L) and abuts against the stop when at least one end position is reached, wherein the adjusting element (19) is drivingly connected to the control element (23) via a torque limiting structure (36).)

1. A cover fitting (1) for pivotably fastening a cover (11) at a furniture body (6), wherein the cover fitting (1) has:

an adjusting element (8) for moving the cover (11),

at least one spring element (14) which is arranged to be loaded with a pretension force between the adjusting element (8) and a bearing (15) in order to force-load the adjusting element (8), and

an adjusting element (19) having a thread (20) which engages with a mating thread (21) of the bearing (15), wherein the bearing (15) can be adjusted in the direction of a longitudinal axis (L) by a rotation of the adjusting element (19) about the longitudinal axis (L) and abuts against a stop when at least one end position is reached,

it is characterized in that the preparation method is characterized in that,

the adjusting element (19) is in driving connection with the control element (23) via a torque limiting structure (36).

2. The cover fitment as set forth in claim 1,

it is characterized in that the preparation method is characterized in that,

the abutment (15) is adjustable in the direction of a first end position by rotation of the adjusting element (19) in a first direction of rotation and in the direction of a second end position by rotation of the adjusting element (19) in a second direction, an

The abutment (15) abuts against a stop (28) when the first end position is reached.

3. The cover fitment as set forth in claim 2,

it is characterized in that the preparation method is characterized in that,

a first torque can be transmitted from the torque limiting structure (36) to the adjusting element (19) when the control element (23) is rotated in the first rotational direction, and

a second torque can be transmitted from the torque limiting structure (36) to the adjusting element (19) when the control element (23) is rotated in the second rotational direction,

wherein the first torque is smaller than the second torque.

4. The cover fitment as set forth in claim 3,

it is characterized in that the preparation method is characterized in that,

when the control element (23) is rotated in the second rotational direction, the adjusting element (19) and the control element (23) are non-rotatably connected by means of the torque limiting structure (36).

5. The lid fitting of any one of claims 1 to 4,

it is characterized in that the preparation method is characterized in that,

the torque limiting structure (36) has a first force transmission surface (31) at the adjusting element (19) and a first force transmission surface (32) at the control element (23), which are in abutting opposition and are each arranged obliquely to a radial plane with respect to the longitudinal axis (L).

6. The cover fitment as set forth in claim 5,

it is characterized in that the preparation method is characterized in that,

the first force transmission surfaces (31, 32) of the adjusting element (19) and of the control element (23) are each designed as helical ramp surfaces.

7. The cover fitment as set forth in claim 6,

it is characterized in that the preparation method is characterized in that,

the first force transmission surface of the adjusting element is embodied as a thread flank of a drive thread and the first force transmission surface of the control element is embodied as a thread flank of a drive mating thread, wherein the control thread and the control mating thread are in engagement with one another.

8. The lid fitting of any one of claims 1 to 7,

it is characterized in that the preparation method is characterized in that,

the torque limiting structure (36) has a second force transmission surface (35) at the adjusting element (19) and a second force transmission surface at the control element (23), which are each arranged obliquely to a radial plane with respect to the longitudinal axis (L).

9. The lid fitting of any one of claims 1 to 8,

it is characterized in that the preparation method is characterized in that,

the cover fitting (1) also has a housing (10) in which at least one spring element (14) is arranged and in which the bearing (15) is non-rotatably axially guided.

10. The cover fitment as set forth in claim 9,

it is characterized in that the preparation method is characterized in that,

the adjusting element (19) is mounted in the housing (10) so as to be rotatable about the longitudinal axis (L).

11. The lid fitting of one of claims 9 or 10,

it is characterized in that the preparation method is characterized in that,

the adjusting element (19) is mounted in the housing (10) so as to be axially displaceable along the longitudinal axis (L).

12. The lid fitting of any one of claims 1 to 11,

it is characterized in that the preparation method is characterized in that,

the adjusting element (19) has a bearing section (33) which is arranged in an opening (34) of the housing (10) in an axially displaceable manner, said opening being formed complementary to the bearing section (33).

13. The lid assembly of any one of claims 1 to 12,

it is characterized in that the preparation method is characterized in that,

the adjusting element (19) has a threaded shaft (22) with the thread (20) in the form of an external thread, and

the mating thread (21) of the support (15) is designed as an internal thread.

14. The lid assembly of any one of claims 1 to 13,

it is characterized in that the preparation method is characterized in that,

the control element (23) has a toothing (24) which is in toothed engagement with a toothing (25) of a drive element (26).

15. The cover fitment as set forth in claim 14,

it is characterized in that the preparation method is characterized in that,

the drive element (26) can be rotated about a drive axis of rotation (D), wherein the drive axis of rotation (D) intersects the longitudinal axis (L) or intersects it at a distance therefrom.

Technical Field

The invention relates to a cover fitting for pivotably fastening a cover to a furniture body, wherein the cover fitting comprises the following elements: an adjustment element for moving the cover; at least one spring element for force-loading the adjusting element, which is arranged between the adjusting element and the bearing with a pre-loading force; and an adjusting element having a thread, the thread of the adjusting element engaging with a mating thread of the abutment, wherein the abutment can be adjusted in the direction of the longitudinal axis by rotation of the adjusting element about the longitudinal axis and abuts against the stop when at least one end position is reached.

Background

Such a cover fitting is known from AT 513387B 1 and has an adjustment drive for moving a movable furniture part. The actuating drive comprises at least one actuating element which is mounted so as to be movable for moving the movable furniture part, a spring device for force-loading the actuating element, and an adjusting device, by means of which the force of the spring device acting on the actuating element can be adjusted. The adjusting device comprises an adjusting screw with a thread, wherein the force of the spring device acting on the adjusting element can be adjusted by means of a nut, which is mounted adjustably along the thread. In order to prevent the nut from becoming jammed with the screw head when the adjusting screw has been rotated to the final position, AT 513387B 1 proposes that the adjusting screw has a region without thread AT the end of the thread facing the head of the adjusting screw, and that AT least one spring element is provided by means of which the nut can exert a force directed away from the end region AT the AT least one end region of the adjusting screw.

An actuating drive for moving a movable furniture part is known from WO 2015/027251 a 1. The actuating drive comprises at least one actuating element which is mounted so as to be movable for moving the movable furniture part, a spring device for applying a force to the actuating element, and an adjusting device, by means of which the force of the spring device acting on the actuating element can be adjusted. The adjusting device has an adjusting screw with a thread section and a nut which is adjustably supported between two end positions and is in engagement with the thread section. By adjusting the nut along the threaded section, the force of the spring means acting on the adjustment element can be adjusted. The adjusting screw has an unthreaded end region at the end of the thread facing the head of the adjusting screw, so that jamming between the nut and the head of the adjusting screw is prevented. Furthermore, a spring element is provided, by means of which the nut can be acted upon away from the head of the adjusting screw, so that the spring element can again enter the thread after being transferred into the thread-free region.

From DE 19918823C 1 a cover fitting is known in the form of a cover adjustment for holding a cover or flap of a piece of furniture. The cover adjuster is for holding the cover in the open position. To this end, the lid adjuster has a first arm and a second arm. The second arm is pivotally connected to the first arm about a pivot axis between an open position and a closed position. The spring means exerts a force on the second arm in a direction towards the open position. Thus, a force is generated by the second arm onto the lid in the direction towards the open position, so that the lid is at least held in the open position. Between an intermediate position between the closed and open positions of the lid and the open position, the forces are balanced such that the lid is automatically moved into the open position or held in any pivoted position. In order to adjust the force exerted by the spring element on the second arm and thus on the cover, the cover adjustment element has a spring pressing element against which the spring device is axially supported. The spring hold-down element has a guide bolt, to which a spring device in the form of a helical spring is fitted. The spring hold-down element is supported internally against the housing of the cover adjustment element by means of a screw screwed into the spring hold-down element. The screw can be adjusted with a screwdriver via a hole in the housing, so that the spring clamping element can be moved axially against the spring force of the helical spring and the helical spring can be pretensioned.

Disclosure of Invention

The object of the invention is to provide a cover fitting which prevents jamming of the bearing and is simple in construction.

This object is achieved by a cover fitting for pivotably fastening a cover to a furniture body, wherein the cover fitting has: an adjustment element for moving the cover; at least one spring element, which is arranged between the adjusting element and the bearing and is loaded with a preload force in order to apply a force to the adjusting element; and an adjusting element with a thread, which engages with a mating thread of the carrier, wherein the carrier can be adjusted in the direction of the longitudinal axis by rotation of the adjusting element about the longitudinal axis and abuts (contacts) the stop when at least one end position is reached, and wherein the adjusting element is in driving connection with the control element via a torque limiting structure.

If the abutment is in contact with the stop in at least one end position, a torque acting on the adjusting element acts on the abutment on the one hand, and a tensioning force from the engagement of the thread of the adjusting element into the mating thread of the abutment, which is proportional to the torque acting on the adjusting element, acts on the abutment on the other hand. Due to both tension and torque, the abutment may get stuck, in particular by the stop.

If the control element is rotated or loaded with a torque by the fitter, the torque limiting structure limits the maximum torque applied to the adjusting element and prevents jamming of the abutment and overloading of the adjusting element or the abutment. Additionally, the assembler may perceptibly receive slippage of the torque limiting coupling when the maximum torque that can be transmitted by the torque limiting structure is exceeded. Thus, the fitter may feel that at least one end position is reached.

The abutment is adjustable in the direction towards a first end position by rotation of the adjustment element in a first rotational direction and in the direction towards a second end position by rotation of the adjustment element in a second rotational direction, wherein the abutment abuts (contacts) the stop when the first end position is reached. In this case, when the control element is rotated in the first rotational direction, a first torque can be transmitted from the torque limiting structure to the adjusting element; and when the control element is rotated in a second rotational direction, a second torque can be transmitted from the torque limiting structure to the adjustment element, wherein the first transmittable torque is smaller than the second transmittable torque. This selection of the transmittable torque as a function of the direction of rotation ensures that jamming of the bearing due to the applied tensioning force is avoided when the control element is rotated in the first direction of rotation. At the same time, when the control element is rotated in the second direction of rotation, a sufficiently large torque can be transmitted to the adjusting element, so that the abutment can be released from the first end position and the pretensioning force of the at least one spring element can be adjusted. In particular, the adjusting element and the control element can be connected in a rotationally fixed (non-rotatable) manner via the torque limiting structure when the control element is rotated in the second rotational direction.

In a possible embodiment of the cover fitting, the torque limiting structure can have a first force transmission surface at the adjusting element and a first force transmission surface at the control element, which abut against (contact) one another and are each arranged obliquely relative to a radial plane with respect to the longitudinal axis. The first force transmitting surface forms a ramp mechanism in the axial direction due to the inclination of the first force transmitting surface relative to a radial plane with respect to the longitudinal axis. The first transferable torque is generated mainly by the gradient of the first force transmission surfaces, the friction coefficient between the two first force transmission surfaces and the pretension force acting on the support. If the abutment abuts against the stop in the first end position, the adjusting element is moved axially away from the control element, i.e. upward, together with the abutment against the biasing force of the at least one spring element, when the first transmittable torque is exceeded, starting from the starting position. In this case, the control element is rotated relative to the adjusting element.

The first force transmission surfaces of the adjusting element and of the control element can be arranged in particular cyclically about the longitudinal axis. The first force transmission surfaces of the adjusting element and of the control element can each be embodied as a helical ramp. The first force transmission surfaces of the adjusting element and the control element, respectively, may follow a spiral line which extends, for example, over 340 degrees, 360 degrees, 380 degrees or multiples of 360 degrees. The helical line may be oriented in the opposite direction to the thread of the adjusting element or the mating thread of the abutment. In particular, the first force transmission surface of the adjusting element can be embodied as a first thread (profile) flank of a drive thread, and the first force transmission surface of the control element can be embodied as a first thread (profile) flank of a drive-fit thread, wherein the drive thread and the drive-fit thread engage in one another.

After the control element has been rotated by a corresponding angular amount of the helical line relative to the adjusting element when the abutment abuts against the stop, the adjusting element is axially released together with the abutment, so that the adjusting element is moved back axially together with the abutment by the pretensioning force of the at least one spring element, wherein the first force transmission surface of the adjusting element and the first force transmission surface of the control element abut against each other again. When the control element is rotated further relative to the adjusting element or when the control element continues to be loaded with a torque greater than the first transmittable torque, the above-described procedure is repeated until the torque acting on the control element is less than the first transmittable torque. The periodic axial movement of the setting element together with the carrier can be described as a ratchet movement.

The first force transmission surfaces of the adjusting element and the control element, respectively, may be inclined at an angle α relative to a radial plane with respect to the longitudinal axis. For adjusting the torque to be transmitted, the angle α of the first force transmission surface may be selected to be constant over an extension in the circumferential direction of the first force transmission surface. The size of the angle α can be selected here to be greater than the lead angle (helix angle) of the thread of the adjusting element or of the mating thread of the abutment. The angle α may be oppositely oriented with respect to the pitch of the adjustment element. It is also conceivable that the angle α is designed to be variable over an extension in the circumferential direction of the first force transmission surface. This results in a defined characteristic of the torque to be transmitted as a function of the angle of rotation between the adjusting element and the control element.

The torque limiting structure may have a second force transmission surface at the adjusting element and a second force transmission surface at the control element, which are each arranged obliquely with respect to a radial plane with respect to the longitudinal axis. The second force transmission surfaces of the adjustment element and the control element may abut (contact) each other when the control element is rotated in the second rotational direction. The second force transmission surface may serve as a locking surface, such that the control element and the adjusting element are non-rotatably connected by the torque limiting structure when the control element is rotated in the second direction. In particular, the second force transmission surface of the adjusting element can be embodied as a second thread flank of the drive thread (second thread profile flank), while the second force transmission surface of the control element can be embodied as a second thread flank of the drive mating thread (second thread profile flank).

The cover fitting can also have a housing in which the at least one spring element is arranged and in which the bearing is axially guided in a rotationally fixed manner (non-rotatable). The adjusting element is mounted in the housing so as to be rotatable about a longitudinal axis. Furthermore, the adjusting element can be mounted in the housing so as to be axially displaceable along the longitudinal axis.

The adjusting element may have a bearing section which is arranged axially movably in an opening of the housing, which opening is configured complementarily to the bearing section. Furthermore, the adjusting element can have a threaded shaft with a thread in the form of an external thread, and the mating thread of the bearing can be configured as an internal thread.

The control element can have a toothing (meshing toothing), in particular an outer toothing, which is in toothed engagement with the toothing (meshing toothing) of the drive element. The drive element can be arranged rotatably about a drive rotation axis, wherein the drive rotation axis intersects the longitudinal axis or intersects it at a distance. The control element and the drive element thus form a bevel gear transmission. The bevel gear transmission can be designed in various known forms, for example as a worm gear, helical gear or bevel gear pair. Furthermore, a transmission may be provided between the drive element and the control element, for example to facilitate rotation of the control element.

Drawings

Preferred embodiments are further elucidated below with reference to the drawing. Shown in the attached drawings:

fig. 1 is a side view of a cover fitting at a furniture in an open position according to the invention, wherein the housing is shown partly transparent for the sake of clarity of the spring element;

fig. 2 is a perspective view of the cover fitting according to fig. 1, wherein the housing is drawn only in dashed lines;

fig. 3 is a perspective view of an adjusting device with a support, an adjusting element of the cover fitting according to fig. 1, a control element and a drive element;

fig. 4 shows a longitudinal section through the adjusting device according to fig. 3, the abutment being in a first end position; and

fig. 5 shows a longitudinal section through the adjusting device according to fig. 3, wherein the support is in an intermediate position during the "ratcheting" movement.

Detailed Description

Fig. 1 to 5 show a cover fitting 1 according to the invention for pivotably fastening a cover 11 to a furniture carcass 6 of a piece of furniture in different views and as will be described in general terms below.

The cover fitting 1 has a base element 2 which is fastened to the furniture body 6 by means of fastening screws 3 and by means of a plurality of fastening pins, not shown, which engage into mounting holes 4 of the side walls 5. Thereby, the base element 2 is fixed at the side wall 5 of the furniture body 6.

The pivot arm 7 is pivotably fastened at the base element 2 about a first body axis K1. At the end remote from the first body axis K1, the pivot arm 7 is connected pivotably about a first cover axis D1 to a pivot-arm-side connecting element 8, which connecting element 8 can also be referred to as a setting element. The first body axis K1 and the first lid axis D1 are spaced apart and arranged parallel to each other.

The connecting element 8 on the pivot arm side is connected to a cover 11 of the piece of furniture via a connecting structure 9. In order to ensure a defined movement sequence of the flap 11 relative to the furniture carcass 6, the flap fitting 1 has a control arm 12 in the present exemplary embodiment, which is pivotably connected about a second carcass axis K2 to the base element 2 and about a second flap axis D2 to the connecting element 8 on the pivot arm side. The second body axis K2 and the second lid axis D2 are spaced apart and parallel to each other and are arranged spaced apart and parallel relative to the first body axis K1 and the first lid axis D1.

The pivot arm 7 and the control arm 12 thus form a four-link chain, which are coupled to one another on the one hand via the base element 2 and on the other hand via the connecting element 8 on the pivot arm side. This presupposes a defined course of movement of the cover 11.

The cover 11 is movable relative to the furniture body 6 by means of the cover fitting 1 between a closed position and an open position shown in fig. 1, wherein the cover 11 closes the opening 13 of the furniture body 6 in the closed position.

The pivot arm 7 has a housing 10 in which a spring element in the form of a helical spring 14 is arranged, which on the one hand bears against the abutment in the vicinity of the first body axis K1 and on the other hand bears against the connecting element 8 on the pivot arm side by means of a pressure element 16 in the vicinity of the first cover axis D1. Since the connecting element 8 on the pivot arm side is connected to the cover 11 by the connecting structure 9, the connecting element 8 on the pivot arm side serves as an adjusting element for moving the cover 11.

In the exemplary embodiment shown in the figures, the pressure element 16 is acted upon with force in the direction of the connecting element 8 on the pivot arm side, wherein the pressure element 16 has a rolling body (roller) 17, with which rolling body 17 the pressure element 16 bears against an adjusting contour (setting contour) 18 of the connecting element 8 on the pivot arm side.

The adjustment profile 18 has a varying distance relative to the first lid axis D1 in a circumferential direction about the first lid axis D1. The adjustment contour 18 is designed such that: a torque is generated by the pressure element 16 on the largest pivoting path of the cover 11 or the connecting element 8 on the pivoting arm side, which torque acts on the cover 11 in the direction of the open position. In the region between the intermediate position between the open position and the closed position of the cover 11 and the closed position, the adjustment contour 18 is configured such that the cover 11 is loaded with a force in the direction of the closed position.

The helical spring 14 is tensioned between the abutment 15 and the adjusting contour 18 at the connecting element 8 on the pivot arm side. The pretensioning by means of which the helical spring 14 is tensioned can be adjusted in order to adapt the cover fitting 1 to different cover weights. Depending on the weight of the cover 11, the pretensioning can be adapted, i.e. the pretensioning (pretensioning force) of the helical spring 14 is increased when the cover weight is greater, as a result of which the rolling bodies (rollers) 17 of the pressure element 16 exert a force on the adjusting contour 18 with greater force, as a result of which a greater torque, in particular in the direction of the open position of the cover 11, acts on the connecting element 8 on the pivot arm side. Accordingly, when the weight of the cover 11 is small, a small pretension (pretension force) can be adjusted.

In order to adjust the pretension (pretensioning force) of the helical spring 14, the abutment 15 can be displaced in the direction of the force action of the helical spring 14, in the exemplary embodiment shown, along the longitudinal axis L of the pivot arm. For this purpose, the support 15 has a rectangular cross section. The housing 10 of the pivot arm 7 also has a rectangular cross section on the inside, by means of which the abutment 15 is guided in a rotationally fixed, axially displaceable manner along the longitudinal axis L.

For adjusting the support 15, an adjusting element 19 having a thread 20 is provided, which is screwed into a mating thread 21 of the support 15, as can be seen in fig. 4 and 5. By rotating the adjusting element 19 about the longitudinal axis L, the abutment 15 is adjusted along the thread 20 in the direction of the longitudinal axis L. The adjusting element 19 is axially displaceably and rotatably mounted in an opening 34 of the housing 10 by means of a cylindrical bearing section 33. In the present exemplary embodiment, the adjusting element 19 is arranged coaxially to the longitudinal axis L. In principle, however, the adjusting element can also be arranged parallel to the axis.

The adjusting element 19 has a threaded rod 22 with a thread 20 in the form of an external thread. The thread 20 is screwed into a mating thread 21 of the support 15, which is designed as an internal thread. Alternatively, the mating thread 21 can also be provided in a separate threaded element, wherein the threaded element is connected to or supported on the support.

Furthermore, the cover fitting comprises a control element 23. The control element 23 has a toothing 24, which meshes with a toothing 25 of a drive element 26. The drive element 26 is rotatable about a drive axis of rotation D, wherein the drive axis of rotation D intersects the longitudinal axis L at a distance. For this purpose, the control element 23 has an opening 37, which is embodied complementary to the bearing section 33 of the adjusting element, and the control element 23 is pushed onto the bearing section 33 by means of the opening 37.

Thus, the control element 23 is rotated about the longitudinal axis L by the drive element 26 being rotated about the drive axis of rotation D. The drive element 26 is designed as a worm gear, wherein the toothing 25 of the drive element 26 is designed as a spiral. The drive element 26 is axially immovably and rotatably supported in the housing 10. In order to be able to turn the drive element 26 with a screwdriver, the drive element 26 has at the end an action means for a tool 27 in the form of a cross-slot. Other means of action are of course also conceivable, such as simple slots or a hexagon socket-type profile.

By converting the rotary movement about the drive axis of rotation D into a rotary movement about the longitudinal axis L, the accessibility (accessibility) of the fitter for changing the pretensioning force of the helical spring 14 is improved in the present exemplary embodiment. The drive element 26 is easily accessible to the installer from the front through the opening 13 of the furniture body 6. In principle, however, embodiments are also possible in which the drive element 26 is omitted and the actuating device for the tool is provided in the adjusting element 19. In this case, the adjustment of the pretension of the helical spring 14 takes place from below at the cover fitting 1.

In the exemplary embodiment shown, when the control element 23 is rotated in a first rotational direction, the abutment 15 can be moved downward, i.e. in the direction of the spring force of the helical spring 14, until a first end position is reached, in which the helical spring 14 has a minimum pretensioning (force). The abutment in this first end position is shown in fig. 4. The support 15 rests here with an access surface 29 on a stop surface 28 of the adjusting element 19. It is also conceivable for the further element to have a stop face. For example, the housing 10 of the pivot arm 7 can have a stop surface.

By rotating the control element 23 in the second direction of rotation, the support 15 can be moved upward in the illustrated embodiment, i.e. against the spring force of the helical spring 14, and away from the first end position until a second end position is reached, in which the helical spring 14 has the greatest pretension (force).

The concepts "lower" and "upper" are given with respect to the mounting position of the cover fitting 1 shown in fig. 1 and 2. In principle, the cover 1 can also be mounted in other positions at the furniture body 6.

In the first end position, the support 15 is loaded with force against the stop face 28 of the adjusting element 19 by the spring force of the helical spring 14. Furthermore, the tensioning force which acts from the adjusting element 19 via the thread 20 on the support 15 and additionally presses it against the stop surface 28 is effective. This can lead to jamming of the abutment 15, so that loosening of the abutment 15 from the first end position against the spring force of the helical spring 14 becomes difficult or even prevented. Furthermore, there is the risk that, when the first end position is reached, an excessive torque acts on the components and leads to damage to one of these components.

The tensioning force acting on the bearing 15 from the adjusting element 19 via the thread 20 is proportional to the torque acting on the adjusting element 19 by the control element 23. The control element 23 and the adjusting element 19 are drivingly connected via a torque limiting structure 36, which can also be referred to as a torque limiting coupling. The torque limiting structure 36 limits the torque that can be transmitted from the control element 23 or from the drive element 26 to the adjusting element 19 depending on the direction of rotation of the control element 23. By means of the torque limiting arrangement 36, the torque exerted by the control element 23 on the adjusting element 19 is limited to a first transmittable torque when the control element 23 is rotated in a first rotational direction and to a second transmittable torque when the control element 23 is rotated in a second rotational direction. This also limits the tension acting between the support 15 and the stop surface 28 and prevents the support from jamming.

The torque limiting structure 36 comprises for this purpose in the case of the present invention a first force transmission surface 31 of the adjusting element 19 and a first force transmission surface 32 of the control element 23, which abut against one another. The first force transmission surfaces 31, 32 are embodied here as complementary inclined surfaces which extend helically in the circumferential direction around parallel lines parallel to the longitudinal axis L of the housing 10. In the present case, the first force transmission surfaces 31, 32 extend 360 ° about the longitudinal axis L of the housing 10. However, it is also conceivable for the first force transmission surfaces 31, 32 to extend for example 340 ° or 380 ° in the circumferential direction. The first torque that can be transmitted by the torque limiting structure 36 in the first direction of rotation is determined primarily by the slope of the first force transmission surfaces 31, 32, the friction ratio between the first force transmission surfaces 31, 32 and the active pretensioning force of the helical spring 14. The first force transmission surfaces 31, 32 have a constant slope gradient in the present case. However, it is also conceivable for the first force transmission surfaces 31, 32 to have a variable circumferential slope, so that the transmittable first torque can be designed variably in the angle of rotation between the adjusting element 19 and the control element 23.

The first force transmission surface 31 of the adjusting element 19 has a starting region or starting position P1 and an end region or end position P2, which are connected to one another via the second force transmission surface 35. The second force transmission surface 35 is arranged in the present case parallel to a plane through the longitudinal axis L of the housing 10 or at an angle of 90 ° relative to a radial plane with respect to the longitudinal axis L, wherein this angle results from the circumferential extension (portion) of the first force transmission surface 31. Based on the sectional views of fig. 4 and 5, the starting and end regions of the first force transmission surface 32 and the second force transmission surface of the control element 23 are covered. The second torque which can be transmitted by the torque limiting structure 36 in the second direction of rotation is mainly determined by the slope gradient of the second force transmission surfaces, the friction ratio between the second force transmission surfaces and the active pretension of the helical spring 14. In the present case, the second force transmission surfaces are configured to complement each other and have a constant slope. However, the second force transmission surface can have a variable gradient, similar to the first force transmission surfaces 31, 32, so that the second torque that can be transmitted can be designed variably in the angle of rotation between the adjusting element 19 and the control element 23.

In the present exemplary embodiment, when the control element 23 is rotated in the first rotational direction, the adjusting element 19 is pushed up along the ramp-shaped force transmission surface 32 of the control element 23 from the starting region to the end region with a torque which is greater than the transmittable first torque, so that the adjusting element 19 is moved axially against the biasing force of the helical spring 14. In this case, the adjusting element 19 and the control element 23 are rotated relative to one another in the circumferential direction. The adjusting element 19 is axially released if the resulting rotational angle of the adjusting element 19 relative to the control element 23 exceeds the circumferential extension of the first force transmission surface 32 of the control element 23. By means of the prestress of the helical spring 14, the adjusting element 19 is axially displaced in the direction of the starting region of the first force transmission surface 32 of the control element 23. The process described above is repeated as long as, for example, the setting element 19 and the control element 23 are rotated relative to one another or the torque acting on the control element 23 is greater than the transmittable first torque, wherein the process can be described as a ratchet movement (unidirectional intermittent movement).

When the control element 23 is rotated in the second direction of rotation, the two second force transmission surfaces abut against (contact) each other and in the present case interact as locking surfaces. The control element 23 and the adjusting element 19 are therefore connected to one another in a form-fitting manner, and the torque acting on the control element 23 can be transmitted completely to the adjusting element 19. However, it is also conceivable for the second force transmission surface to form a ramp mechanism, similar to the first force transmission surface, so that the torque limiting and "ratchet" function in the second direction of rotation, as described above for the first direction of rotation, can also be realized.

At the end of the threaded rod 22 arranged remote from the gear wheel 23, the threaded rod has a thread-free section 30. If the abutment 15 is moved in the direction from the first end position to the second end position, the mating thread 21 of the abutment 15 is withdrawn from the thread 20 of the adjusting element 19. In this position, the adjustment element 19 can rotate freely with respect to the support 15, without the support 15 moving axially, since the mating thread 21 is disengaged from the thread 20. Jamming in the upper end position is thus precluded.

If the adjusting element 19 is then rotated again in the other direction, the mating thread 21 again engages with the thread 20, since the helical spring 14 presses the abutment 15 against the threaded end of the thread 20 in the transition to the unthreaded section 30.

List of reference numerals

1 cover fitting

2 biasing element

3 fastening screw (bolt)

4 mounting hole

5 side wall

6 furniture body

7 pivoting arm

8 connecting element of pivoting arm

9 connection structure

10 casing

11 cover

12 control arm

13 opening

14 helical spring

15 support

16 pressure element

17 Rolling element (roller)

18 set profile

19 adjusting element

20 screw thread

21 mating threads

22 screw shaft

23 control element

24 tooth system

25 tooth system

26 drive element

27 acting device for tool

28 stop surface

29 approach surface

30 unthreaded part section

31 first force transmission surface

32 first force transmitting surface

33 support section

34 opening

35 second force transmission surface

36 torque limiting structure

37 opening

L longitudinal axis

D drive axis of rotation

K body axis.