阅读说明：本技术 一种金属材料加工用防护装置及其安全防护措施 (Protective device for metal material processing and safety protection measure thereof ) 是由 孙铭 于 2021-07-04 设计创作，主要内容包括：本发明公开了一种金属材料加工用防护装置及其安全防护措施,包括机台、鼓风机本体和负压风机本体,所述机台上表面一侧固定有第一竖板,所述第一竖板一侧底部固定有出风槽,所述第一竖板底部嵌入安装有出风斗,所述出风斗一侧固定有第一弯管,所述第一弯管底端固定有第一连接管,所述第一连接管的底端与鼓风机本体的出风端固定,所述机台上表面另一侧固定有第二竖板,所述第二竖板一侧底部固定有进风槽,所述第二竖板底部嵌入安装有进风斗,所述进风斗一侧的中间固定有第二弯管,所述第二弯管底端固定有第二连接管,所述第二连接管的底端与负压风机本体的进风端固定。本发明具有竖板阻挡飞溅的金属碎屑,快速高效的将金属碎屑清理收集的优点。(The invention discloses a protective device for metal material processing and a safety protection measure thereof, which comprises a machine table, a blower body and a negative pressure fan body, a first vertical plate is fixed on one side of the upper surface of the machine table, an air outlet groove is fixed at the bottom of one side of the first vertical plate, an air outlet hopper is embedded in the bottom of the first vertical plate, a first bent pipe is fixed on one side of the air outlet hopper, a first connecting pipe is fixed at the bottom end of the first bent pipe, the bottom end of the first connecting pipe is fixed with the air outlet end of the blower body, a second vertical plate is fixed on the other side of the upper surface of the machine table, an air inlet groove is fixed at the bottom of one side of the second vertical plate, an air inlet hopper is embedded in the bottom of the second vertical plate, a second bent pipe is fixed in the middle of one side of the air inlet hopper, and a second connecting pipe is fixed at the bottom end of the second bent pipe, and the bottom end of the second connecting pipe is fixed with the air inlet end of the negative pressure fan body. The invention has the advantages that the vertical plate blocks splashed metal scraps, and the metal scraps are quickly and efficiently cleaned and collected.)

1. The utility model provides a protector is used in metal material processing, includes board (1), cutting frock (2), air-blower body (5), negative-pressure air fan body (19) and box (23), its characterized in that: a first vertical plate (10) is fixed on one side of the upper surface of the machine table (1), an air outlet groove (3) is fixed at the bottom of one side of the first vertical plate (10), an air outlet hopper (8) is installed at the bottom of the first vertical plate (10) in an embedded mode, a first bent pipe (7) is fixed in the middle of the air outlet hopper (8) deviating from one side of the first vertical plate (10), a first connecting pipe (6) is fixed at the bottom end of the first bent pipe (7), the first connecting pipe (6), the first bent pipe (7) and the air outlet hopper (8) are sequentially communicated, the bottom end of the first connecting pipe (6) is fixed at the air outlet end of the air blower body (5), a second vertical plate (13) is fixed on the other side of the upper surface of the machine table (1), an air inlet groove (15) is fixed at the bottom of one side of the second vertical plate (13), an air inlet hopper (16) is installed at the bottom of the second vertical plate (13), and a second bent pipe (17) is fixed in the middle of the air inlet hopper (16) deviating from one side of the second vertical plate (13), second return bend (17) bottom mounting has second connecting pipe (18), and second connecting pipe (18), second return bend (17) and air inlet fill (16) communicate in proper order, the bottom of second connecting pipe (18) is fixed with the air inlet end of negative pressure fan body (19).

2. The metal material processing protective device according to claim 1, wherein: the middle of the upper surface of the machine table (1) is welded with four pillars (25) in a rectangular array mode, the tops of the four pillars (25) are welded with four corners of the lower surface of the cutting tool (2), and a cutting groove (26) is formed in the middle of the upper surface of the cutting tool (2).

3. The metal material processing protective device according to claim 1, wherein: a second baffle (11) is fixed above one side of the first vertical plate (10), a first baffle (9) is fixed below one side of the first vertical plate (10), and the first baffle (9) is located above the air outlet groove (3).

4. The metal material processing protective device according to claim 1, wherein: a first embedded groove matched with the air outlet hopper (8) is formed in the bottom of the first vertical plate (10), the air outlet hopper (8) is located in the first embedded groove, and the air outlet hopper (8) is communicated with the air outlet groove (3).

5. The metal material processing protective device according to claim 1, wherein: a third baffle (12) is fixed above one side of the second vertical plate (13), a fourth baffle (14) is fixed below one side of the second vertical plate (13), and the fourth baffle (14) is located above the air inlet groove (15).

6. The metal material processing protective device according to claim 1, wherein: and a second embedded groove matched with the air inlet hopper (16) is formed in the bottom of the second vertical plate (13), the air inlet hopper (16) is positioned in the second embedded groove, and the air inlet hopper (16) is communicated with the air inlet groove (15).

7. The metal material processing protective device according to claim 1, wherein: the bottom end of the air blower body (5) is fixed with a first base (4), and the bottom end of the negative pressure air blower body (19) is fixed with a second base (20).

8. The metal material processing protective device according to claim 1, wherein: the air outlet end of the negative pressure fan body (19) is connected with one side of the box body (23) through a third connecting pipe (22), the box body (23) is positively rotated to be provided with a box door (21), one side of the top end of the box body (23) is fixedly provided with an exhaust pipe (24), the exhaust pipe (24) is communicated with the inside of the box body (23), a frame (27) is fixedly arranged above the inside of the box body (23), and a filter screen (28) is fixedly arranged in the middle of the frame (27).

9. The utility model provides a metal material processing is with protector's safety protection measure which characterized in that: a protection step:

s1, the machine table (1) is installed in a cutting equipment chassis, the cutting tool (2) corresponds to the saw blade, the metal material is conveyed to the cutting tool (2) to be fixed, and the cutting equipment cuts the metal material;

s2, when the metal material is cut, splashed chips are hit on the first vertical plate (10) and the second vertical plate (13), the chips fall downwards under the action of gravity, the chips fall on the machine table (1) along the first baffle (9) and the fourth baffle (14), and meanwhile the second baffle (11) and the third baffle (12) block the chips to avoid the chips from flying out;

s3, starting a blower body (5), compressing external air by the blower body (5), blowing air into an air outlet hopper (8) through a first connecting pipe (6) and a first bent pipe (7), blowing the air out of an air outlet groove (3), and moving chips generated by cutting to an air inlet groove (15) along a machine table (1) under the action of the air blown out of the air outlet groove (3);

s4, starting a negative pressure fan body (19), generating negative pressure in a second bent pipe (17) and a second connecting pipe (18), enabling chips on a machine table (1) to enter an air inlet groove (15) under the combined action of the negative pressure and air blown out from an air outlet groove (3), enabling the chips to enter a box body (23) from the second bent pipe (17) and the second connecting pipe (18) through a third connecting pipe (22) along an air inlet hopper (16), collecting the chips in the box body (23), discharging air in the box body (23) from an exhaust pipe (24), discharging only air out of the exhaust pipe (24) under the obstruction of a filter screen (28), and keeping the chips in the box body (23).

Technical Field

The invention relates to the technical field of metal material processing protection, in particular to a protection device for metal material processing and a safety protection measure thereof.

Background

The metal material is a material having properties such as luster, ductility, easy electrical conduction, and heat transfer. Generally, the method is divided into ferrous metal and nonferrous metal. Ferrous metals include iron, chromium, manganese, and the like. Where steel is the basic structural material, known as "industrial skeleton". Due to the progress of science and technology, the wide application of various novel chemical materials and novel non-metallic materials leads the substitute of steel to be increased continuously, and the demand of steel is relatively reduced. However, the dominance of steel in the construction of industrial raw materials has been difficult to replace so far.

The properties of the metallic material determine the applicability and the rationality of the application of the material. The properties of metal materials are mainly divided into four aspects, namely: mechanical properties, chemical properties, physical properties, processing properties.

The metal material is processed by different processing techniques according to the type of the finished product to be processed, but cutting is a necessary process for processing the metal material. The metal material is cut into a desired shape by a cutting device.

Cutting device is when cutting the operation to metal material, and high-speed pivoted saw bit and metal material contact cutting can produce the piece, and the piece splashes and can injure the staff by mistake, and the piece that splashes simultaneously falls into the normal use that also can influence equipment in the equipment, clears up the trouble of ten minutes.

Disclosure of Invention

The invention aims to provide a protective device for metal material processing and a safety protection measure thereof, which have the advantages that the vertical plates are respectively arranged at the front end and the rear end of a metal material cutting position to block splashed metal scraps, and simultaneously, the metal scraps are quickly and efficiently cleaned and collected, so that the problems that scraps are generated when a saw blade rotating at a high speed is in contact with a metal material for cutting, the scraps splashed can accidentally injure workers, meanwhile, the normal use of equipment can be influenced when the splashed scraps fall into the equipment, and the cleaning is very troublesome are solved.

In order to achieve the purpose, the invention provides the following technical scheme: a protection device for metal material processing comprises a machine table, a cutting tool, an air blower body, a negative pressure fan body and a box body, wherein a first vertical plate is fixed on one side of the upper surface of the machine table, an air outlet groove is fixed on the bottom of one side of the first vertical plate, an air outlet hopper is installed at the bottom of the first vertical plate in an embedded mode, a first bent pipe is fixed in the middle of the air outlet hopper, which is far away from one side of the first vertical plate, the bottom end of the first bent pipe is fixedly provided with a first connecting pipe, the first bent pipe and the air outlet hopper are sequentially communicated, the bottom end of the first connecting pipe is fixed with the air outlet end of the air blower body, a second vertical plate is fixed on the other side of the upper surface of the machine table, an air inlet groove is fixed on the bottom of one side of the second vertical plate, an air inlet hopper is installed at the bottom of the second vertical plate in an embedded mode, a second bent pipe is fixed in the middle of the air inlet hopper, which is far away from one side of the second vertical plate, the bottom end of the second bent pipe is fixedly provided with a second connecting pipe, the second connecting pipe, the second bent pipe and the air inlet hopper are communicated in sequence, and the bottom end of the second connecting pipe is fixed with the air inlet end of the negative pressure fan body.

As a further scheme of the invention, four pillars are welded in the middle of the upper surface of the machine table in a rectangular array mode, the top ends of the four pillars are welded with four corners of the lower surface of the cutting tool, and a cutting groove is formed in the middle of the upper surface of the cutting tool.

As a further scheme of the invention, a second baffle is fixed above one side of the first vertical plate, a first baffle is fixed below one side of the first vertical plate, and the first baffle is positioned above the air outlet groove.

As a further scheme of the invention, a first embedded groove matched with the air outlet hopper is formed in the bottom of the first vertical plate, the air outlet hopper is positioned in the first embedded groove, and the air outlet hopper is communicated with the air outlet groove.

As a further scheme of the invention, a third baffle is fixed above one side of the second vertical plate, a fourth baffle is fixed below one side of the second vertical plate, and the fourth baffle is positioned above the air inlet tank.

As a further scheme of the invention, a second embedded groove matched with the air inlet hopper is formed in the bottom of the second vertical plate, the air inlet hopper is positioned in the second embedded groove, and the air inlet hopper is communicated with the air inlet groove.

As a further scheme of the invention, a first base is fixed at the bottom end of the blower body, and a second base is fixed at the bottom end of the negative pressure blower body.

As a further scheme of the invention, the air outlet end of the negative pressure fan body is connected with one side of the box body through a third connecting pipe, the box door is rotatably arranged on the front surface of the box body, an exhaust pipe is fixed on one side of the top end of the box body and is communicated with the interior of the box body, a frame is fixed above the interior of the box body, and a filter screen is fixed in the middle of the frame.

A safety protection measure of a protection device for metal material processing comprises the following protection steps:

s1, installing the machine table in a cutting equipment case, enabling the cutting tool to correspond to the saw blade, conveying the metal material to the cutting tool for fixing, and cutting the metal material by the cutting equipment;

s2, when the metal material is cut, splashed chips are hit on the first vertical plate and the second vertical plate, the chips fall downwards under the action of gravity, the chips fall on the machine table along the first baffle and the fourth baffle, and meanwhile the second baffle and the third baffle block the chips, so that the chips are prevented from flying out;

s3, starting the blower body, compressing external air by the blower body, blowing air into the air outlet hopper through the first connecting pipe and the first bent pipe, blowing the air out of the air outlet groove, and moving fragments generated by cutting to the air inlet groove along the machine table under the action of the air blown out of the air outlet groove;

s4, the negative-pressure air blower body starts, produce the negative pressure in second return bend and the second connecting pipe, piece on the board enters into the air inlet tank under the combined action of the wind that negative pressure and play wind groove blown out, the piece enters into in the box through the third connecting pipe from second return bend and second connecting pipe along the air inlet hopper, the piece is collected in the box, gas in the box is discharged from the exhaust pipe, under the separation of filter screen, the exhaust pipe only gas outgoing, the piece is stayed in the box.

Compared with the prior art, the invention has the following beneficial effects:

1. according to the invention, the air outlet groove, the air outlet hopper, the air inlet groove, the air inlet hopper and the box body are arranged, so that the effects of quickly and efficiently cleaning and collecting metal scraps are achieved. The metal material cutting machine is provided with an air outlet groove, an air outlet hopper, an air inlet groove, an air inlet hopper and a box body, wherein a machine table is installed in a machine box of cutting equipment, a cutting tool corresponds to a saw blade, a metal material is conveyed to the cutting tool to be fixed, and the cutting equipment cuts the metal material. The air blower body starts, and the air blower body blows off gas in to the air-out fill through first connecting pipe and first return bend after with outside air compression, and gas blows off from the air-out groove, and the piece that the cutting produced moves to the air inlet duct department along the board under the effect of the wind that the air-out groove blew off. The negative-pressure air blower body starts, produces the negative pressure in second return bend and the second connecting pipe, piece on the board enters into the air inlet duct under the combined action of the wind that negative pressure and play air duct blown out, the piece enters into in the box through the third connecting pipe from second return bend and second connecting pipe along the air inlet fill, the piece is collected in the box, gas in the box is discharged from the exhaust pipe, under the separation of filter screen, the exhaust pipe only gas outgoing, the piece is stayed in the box. The metal scraps are quickly and efficiently cleaned and collected under the combined action of the negative pressure and the air blown out from the air outlet groove.

2. According to the invention, the first vertical plate, the second vertical plate, the first baffle plate, the second baffle plate, the third baffle plate and the fourth baffle plate are arranged, so that the effect that the vertical plates are respectively arranged at the front end and the rear end of a metal material cutting position to block splashed metal scraps is achieved. The machine table is provided with the first vertical plate, the second vertical plate, the first baffle, the second baffle, the third baffle and the fourth baffle, when metal materials are cut, splashed fragments strike the first vertical plate and the second vertical plate, the fragments fall downwards under the action of gravity, the fragments fall on the machine table along the first baffle and the fourth baffle, and meanwhile the second baffle and the third baffle block the fragments, so that the fragments are prevented from flying out. The front end and the rear end of the metal material cutting position are respectively provided with a vertical plate for blocking splashed metal scraps, so that workers are protected.

Drawings

FIG. 1 is a schematic front view of the present invention;

FIG. 2 is an enlarged schematic view taken at A of FIG. 1 in accordance with the present invention;

FIG. 3 is a left side view of the present invention;

FIG. 4 is a schematic top view of the present invention;

FIG. 5 is a schematic view of the connection structure of the case body in a front cross section;

fig. 6 is a schematic view of a top connection structure of the frame according to the present invention.

In the figure: 1. a machine platform; 2. cutting a tool; 3. an air outlet groove; 4. a first base; 5. a blower body; 6. a first connecting pipe; 7. a first bend pipe; 8. an air outlet hopper; 9. a first baffle plate; 10. a first vertical plate; 11. a second baffle; 12. a third baffle plate; 13. a second vertical plate; 14. a fourth baffle; 15. an air inlet groove; 16. an air inlet hopper; 17. a second bend pipe; 18. a second connecting pipe; 19. a negative pressure fan body; 20. a second base; 21. a box door; 22. a third connecting pipe; 23. a box body; 24. an exhaust duct; 25. a pillar; 26. cutting the groove; 27. a frame; 28. and (5) filtering by using a filter screen.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front", "rear", "both ends", "one end", "the other end", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "disposed," "connected," and the like are to be construed broadly, such as "connected," which may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Example 1

Referring to fig. 1, fig. 2 and fig. 4, an embodiment of the present invention: the utility model provides a protector is used in metal material processing, includes board 1 and cutting frock 2, and the centre of 1 upper surface of board is the welding of rectangle array has four pillars 25, and the welding of four corners departments is left with 2 lower surfaces of cutting frock on the top of four pillars 25, leaves the space between 2 lower surfaces of cutting frock and the 1 upper surface of board, makes things convenient for the piece to pass through, and the centre of 2 upper surfaces of cutting frock has been seted up and has been cut 26. The machine table 1 is installed in a cutting equipment case, the cutting tool 2 corresponds to a saw blade, and a metal material is conveyed to the cutting tool 2 and fixed.

A first vertical plate 10 is fixed on one side of the upper surface of the machine table 1, a second baffle 11 is fixed above one side of the first vertical plate 10, a first baffle 9 is fixed below one side of the first vertical plate 10, and the first baffle 9 is located above the air outlet groove 3. A second vertical plate 13 is fixed on the other side of the upper surface of the machine table 1, a third baffle 12 is fixed above one side of the second vertical plate 13, a fourth baffle 14 is fixed below one side of the second vertical plate 13, and the fourth baffle 14 is positioned above the air inlet slot 15. When the metal material is cut, splashed chips hit the first vertical plate 10 and the second vertical plate 13, the chips fall downwards under the action of gravity, the chips fall on the machine table 1 along the first baffle 9 and the fourth baffle 14, and meanwhile the second baffle 11 and the third baffle 12 block the chips, so that the chips are prevented from flying out.

Example 2

Referring to fig. 1, fig. 3, fig. 4, fig. 5 and fig. 6, an embodiment of the present invention: the utility model provides a protector is used in metal material processing, includes board 1, air-blower body 5, negative-pressure air fan body 19 and box 23, and 1 upper surface one side of board is fixed with first riser 10, and first riser 10 one side bottom is fixed with out wind groove 3, and wind hopper 8 is installed in the embedding of first riser 10 bottom, and first embedded groove with wind hopper 8 assorted is seted up to first riser 10 bottom, and wind hopper 8 is located first embedded groove, and wind hopper 8 communicates with play wind groove 3. The middle of one side of the air outlet hopper 8, which deviates from the first vertical plate 10, is fixedly provided with a first bent pipe 7, the bottom end of the first bent pipe 7 is fixedly provided with a first connecting pipe 6, the first bent pipe 7 and the air outlet hopper 8 are sequentially communicated, the bottom end of the first connecting pipe 6 is fixed with the air outlet end of the air blower body 5, as is well known to those skilled in the art, the air blower body 5 is provided with a common knowledge, the air blower belongs to a conventional means or common general knowledge, and is not repeated herein, the skilled in the art can carry out any matching according to the needs or the convenience of the air blower body, and the bottom end of the air blower body 5 is fixedly provided with a first base 4. The air blower body 5 is started, air is blown out of the air outlet hopper 8 through the first connecting pipe 6 and the first bent pipe 7 after external air is compressed by the air blower body 5, the air is blown out of the air outlet groove 3, and chips generated by cutting move to the air inlet groove 15 along the machine table 1 under the action of air blown out of the air outlet groove 3.

A second vertical plate 13 is fixed to the other side of the upper surface of the machine table 1, an air inlet groove 15 is fixed to the bottom of one side of the second vertical plate 13, an air inlet hopper 16 is installed at the bottom of the second vertical plate 13 in an embedded mode, a second embedded groove matched with the air inlet hopper 16 is formed in the bottom of the second vertical plate 13, the air inlet hopper 16 is located in the second embedded groove, and the air inlet hopper 16 is communicated with the air inlet groove 15. A second bent pipe 17 is fixed in the middle of one side, away from the second vertical plate 13, of the air inlet hopper 16, a second connecting pipe 18 is fixed at the bottom end of the second bent pipe 17, the second connecting pipe 18, the second bent pipe 17 and the air inlet hopper 16 are sequentially communicated, the bottom end of the second connecting pipe 18 is fixed with the air inlet end of the negative pressure fan body 19, as is well known to those skilled in the art, the negative pressure fan body 19 is used for providing common knowledge, the negative pressure fan body belongs to conventional means or common general knowledge, and is not described herein any more, the skilled in the art can perform any matching according to needs or convenience of the person, and a second base 20 is fixed at the bottom end of the negative pressure fan body 19. The negative pressure fan body 19 is started, negative pressure is generated in the second bent pipe 17 and the second connecting pipe 18, and chips on the machine table 1 enter the air inlet groove 15 under the combined action of the negative pressure and air blown out from the air outlet groove 3.

The air outlet end of the negative pressure fan body 19 is connected with one side of the box body 23 through a third connecting pipe 22, the box door 21 is rotatably installed on the front surface of the box body 23, an exhaust pipe 24 is fixed on one side of the top end of the box body 23, the exhaust pipe 24 is communicated with the interior of the box body 23, a frame 27 is fixed above the interior of the box body 23, a filter screen 28 is fixed in the middle of the frame 27, and the mesh number of the filter screen 28 is selected by a technician in the field according to actual conditions. The scraps enter the box body 23 from the second bent pipe 17 and the second connecting pipe 18 through the third connecting pipe 22 along the air inlet hopper 16, the scraps are collected in the box body 23, the air in the box body 23 is discharged from the exhaust pipe 24, only the air is discharged from the exhaust pipe 24 under the obstruction of the filter screen 28, and the scraps are remained in the box body 23.

Example 3

The embodiment provided by the invention comprises the following steps: a safety protection measure of a protection device for metal material processing comprises the following protection steps:

s1, the machine table 1 is installed in a cutting equipment cabinet, the cutting tool 2 corresponds to a saw blade, a metal material is conveyed to the cutting tool 2 to be fixed, and the cutting equipment cuts the metal material;

s2, when the metal material is cut, splashed chips hit the first vertical plate 10 and the second vertical plate 13, the chips fall downwards under the action of gravity, the chips fall on the machine table 1 along the first baffle 9 and the fourth baffle 14, and meanwhile the second baffle 11 and the third baffle 12 block the chips to avoid the chips from flying out;

s3, starting the blower body 5, compressing external air by the blower body 5, blowing air into the air outlet hopper 8 through the first connecting pipe 6 and the first bent pipe 7, blowing the air out of the air outlet groove 3, and moving the cut fragments to the air inlet groove 15 along the machine table 1 under the action of air blown out of the air outlet groove 3;

s4, the negative pressure fan body 19 is started, negative pressure is generated in the second elbow pipe 17 and the second connecting pipe 18, fragments on the machine table 1 enter the air inlet groove 15 under the combined action of the negative pressure and air blown out from the air outlet groove 3, the fragments enter the box body 23 from the second elbow pipe 17 and the second connecting pipe 18 through the third connecting pipe 22 along the air inlet hopper 16, the fragments are collected in the box body 23, air in the box body 23 is exhausted from the exhaust pipe 24, the exhaust pipe 24 only exhausts the air under the obstruction of the filter screen 28, and the fragments are remained in the box body 23.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.