stapler

Abstract

The invention relates to a stapler, comprising an anvil leg and a staple unit, the staple unit comprising a staple magazine and a drive, the drive being used to press staples through paper, the stapler comprising a lower part, the anvil leg being movable toward the lower part against a restoring force, the stapler comprising two bending levers pivotably supported on the anvil leg about a respective pivot axis, the bending levers comprising a first lever arm and a second lever arm, the first lever arm having a bending surface for bending the staple legs, the second lever arm pivoting about the pivot axis when the anvil leg approaches the lower part, and the bending surfaces bending the staple legs toward each other, wherein the pivot axis extends substantially perpendicularly to a staple bridge of a staple accommodated in the staple magazine, and the second lever arm having end sections starting at its free end, the end sections being arranged offset from each other in the axial direction of the pivot axis, so that the end sections move past each other when the anvil leg approaches the lower part.

Description

Technical Field

[0001] The invention relates to a stapler. Background Art

[0002] This stapler is disclosed by EP1480788B1. The configuration of the stapler has an anvil leg that can overcome the reset force and move toward the lower part of the machine and a two-arm bending lever that can be pivotally supported on the anvil leg. The bending lever bends the staple leg that is guided through the paper when the anvil leg is pressed down and cuts off the redundant end portion of the staple leg by pressing it onto the cutting edge of the cutting table, which can realize that the same staple is always used for paper with very different total thicknesses. If only a few pages are bound together, the staple leg is actually too long for the total thickness of these pages, so the redundant end portion of the staple leg is simply cut off. In order not to collide with each other during the bending process, each bending lever is staggered in a direction extending perpendicularly to the staple top of the staple accommodated in the staple magazine. However, in order to realize that the two staple legs are acted on by one of the bending levers, the pivot axis of the bending lever is not arranged in a direction extending perpendicularly to the staple top, but is relatively rotated out from this direction. This results in the staple legs not bending exactly towards the staple top when bending, but bending at a distance beside the staple top. As a result, when the excess end portion is cut off, a cut-off edge is produced which does not extend perpendicularly to the longitudinal extension direction of the staple legs. This can lead to increased wear of the cut edge or even to the staple legs getting stuck at the cut edge. Summary of the invention

[0003] It is therefore an object of the present invention to further develop a stapler of the type mentioned at the outset in such a way that it is less susceptible to wear and / or malfunctions.

[0004] According to the invention, this object is achieved by a stapler according to the invention.

[0005] The concept on which the present invention is based is that the second lever arm of each bending lever is configured in such a way that even when the second lever arm is arranged opposite to each other with a pivot axis extending substantially perpendicular to the staple top of the staple contained in the magazine, the second lever arms move past each other during the bending process. Here, the pivot axis extends at an angle of 90°±2° and preferably at an angle of 90°±1° to the staple top, respectively. Ideally, each of the pivot axes extends precisely perpendicular to the staple top of the staple contained in the magazine within the scope of general manufacturing accuracy. Therefore, in the sense that the free ends of the bending levers have the same spacing relative to the lower part of the machine, the bending levers can be arranged at the same position opposite to each other.

[0006] Preferably, the thickness of the end section measured in the axial direction of the pivot axis is smaller than the maximum thickness of the first lever arm. It is further preferred that the two curved surfaces have the same extension in the axial direction of the pivot axis. Although the curved surfaces should be as large as possible in order to reliably grip the nail legs guided through the paper material, it is advantageous if the end sections are designed to be thinner so that they can be guided past each other well during the bending process.

[0007] The first lever arms are expediently arranged mirror-symmetrically to one another about a symmetry plane extending between the pivot axes in the middle perpendicular to the staple bridge of the staples accommodated in the staple magazine. This simplifies the most symmetrical possible deformation of the staple legs. It is further preferred that the thickness of the end sections is at most half the maximum thickness of the first lever arms so that the end sections can reliably move past one another.

[0008] Advantageously, the pivot axes are arranged at such a distance from each other that the first lever arm can move past the cutting edge. Therefore, the first lever arm can also move further after the redundant end portion of the nail leg is separated until the nail leg is pressed onto the back side of the bound paper materials.

[0009] The placement plate expediently has openings on both sides of the cutting table for the free ends of the nail legs to be guided through after piercing the paper. In order to be able to press the nail legs against the lower side of the paper to be stapled together, the curved surface can advantageously be pivoted from a rest position, in which the curved surface is arranged at a positive acute angle to the placement surface on the upper side of the placement plate, into a stapling position when the anvil legs approach the lower part. In the stapling position, the curved surface is arranged parallel to the placement surface or at a negative acute angle to the placement surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The invention will be explained in more detail below with the aid of an exemplary embodiment schematically shown in the accompanying drawings.

[0011] Figure 1 showing a stapler in perspective view;

[0012] Figure 2 Shown installed according to Figure 1 A structural assembly in a stapler, the structural assembly having a cutting table and two curved levers;

[0013] Figure 3a , Figure 3b A side view showing Figure 2 A structural assembly wherein one of the side panels has been removed and the bending lever is in two different positions; and

[0014] Figure 4a , Figure 4bThe curved lever is shown in side view and in perspective view. DETAILED DESCRIPTION

[0015] The stapler 10 shown in the drawings is used to bind paper materials together by means of staples 12, such as by Figure 3a , Figure 3b It can be seen that the staples each have two legs 14 and a staple bridge 16 which connects the legs 14 to each other and extends transversely to the legs. Thus, the staple 12 has a U-shaped shape which is open downwards, wherein during the stapling process the legs 14 pierce the paper with their free ends and bend on the underside of the paper.

[0016] The stapler has a lower part 18, which extends from a rear end 22 to a front end 24 in a longitudinal direction 20 and carries an anvil leg 26, which is supported on the lower part 18 to move toward the lower part against a restoring force, such as a restoring force of a spring. In the present embodiment, the anvil leg 26 is pivotably supported on the lower part 18 in the region of a bearing seat 28 arranged near the rear end 22. In addition, the stapler 10 has a staple unit 30, which has a staple magazine 32, in which the staples 12 are arranged in rows and abut against each other. In the row, the staple bridges are oriented parallel to each other, wherein, except for the foremost and the last, each staple bridge 16 is arranged between two adjacent staple bridges 16 and abuts against these two adjacent staple bridges. In addition, the staple unit 30 has a handle 34, which extends obliquely upward from the bearing seat 28 and extends in the direction of the rear end 22. A driver 36 is provided on the handle 34, and the handle 34 is supported on the bearing seat 28 so as to be pivotable downwards relative to the lower part 18 and the staple magazine 32, respectively, against a restoring force. In addition, the staple magazine 32 is supported on the bearing seat 28 so as to be pivotable relative to the lower part 18. The anvil leg 26 has a placement plate 38 for placing paper materials, wherein during the stapling process, the handle 34 is pressed downwards, thereby pressing the staple magazine 32 downwards onto the paper materials, and wherein, finally, with the use of an increased force, the driver 36 presses the front staple 12 through the paper materials with the free end of the staple leg 14 of the staple first.

[0017] The stapler 10 is characterized in that only a single size of staples 12 is required for paper materials of different thicknesses (in the present case for paper materials consisting of 2 to 170 sheets), since the excess end portions of the staple legs 14 are cut off during the stapling process. For this purpose, the anvil legs carry a cutting table 40 having two cutting edges 42 arranged on sides of the cutting table 40 facing away from each other, wherein the projection of the cutting edges 42 onto a standing surface 44 on the lower side of the lower part 18 extends in the longitudinal direction 20, with which the stapler 10 can be placed flat on a base, such as a desk. As a result, the cutting edges 42 also always extend perpendicularly to the staple bridge 16 of the staples 12 accommodated in the staple magazine 32 within the scope of normal manufacturing accuracy, since the row of staples 12 also extends in the longitudinal direction 20 in its projection onto the standing surface 44. Figure 2 , Figure 3a , Figure 3b The structural assembly 46 shown in the figure, to which the cutting table 40 belongs and which is fixedly connected to the anvil leg 26, also has two identical bending levers 50 arranged between two side plates 48. Each of the bending levers 50 can be pivotally supported on the anvil leg 26 between the side plates 48 about a pivot axis 52. The bending levers have a first lever arm 54 and a longer second lever arm 58, which has a curved surface 56 on the upper side and is placed on the lower part 18. The projection of the pivot axis 52 into the setting surface 44 extends in the longitudinal direction 20. Therefore, the pivot axis 52 extends perpendicularly to the staple bridge 16 of the staples 12 accommodated in the staple magazine 32 within the manufacturing tolerance.

[0018] When the anvil leg 26 is pressed downwardly in the direction of the lower member 18 during the stapling process, the second lever arm 58 is pressed toward the bottom of the lower member 18, thereby causing the bending lever 50 to pivot about the pivot axis 52. Figure 1In the static position shown in , the bending lever 50 is also in the static position, in which the bending surface 56 is arranged at a positive acute angle with the placement surface 60 on the upper side of the placement plate 38. This angle becomes smaller during the binding process, that is, when the bending lever 50 is pivoted. Here, the free ends of the nail legs 14 are respectively abutted on one of the bending surfaces 56 after piercing the paper, and the end sections of the nail legs 14 that pierce the paper are bent toward each other by means of the pivoting of the bending lever 50. The possible redundant end portion of the nail legs 14, which are implemented as very long nail legs 14 in this embodiment, is pressed against the cutting edge 42 by the bending lever 50 during bending and is cut off. In order to be able to abut on the bending surface 56, the nail legs 14 are guided through the opening 62 in the placement plate 38 with the free ends of the nail legs after piercing the paper. The pivot axes 52 are arranged at such a distance from each other and the first lever arm 54 is dimensioned so that the first lever arm can move past the cutting edge 42 when the bending lever 50 is pivoted. The bending lever 50 can then be pivoted from the rest position into an end position in which its bending surface 56 is arranged parallel to the placement surface or at an acute negative angle to the placement surface.

[0019] The first lever arms 54 are arranged mirror-symmetrically to one another with respect to a symmetry plane extending in the middle in the longitudinal direction 20 between the pivot axes 52. In the axial direction of the pivot axes 52, the curved surfaces 56 also have the same extension. The second lever arm 58, on the other hand, has an end section 66 which begins at its free end 64 and extends a distance in the direction of the respective pivot axis 52, the thickness of which, measured in the axial direction of the pivot axis 52, is less than the maximum thickness of the first lever arm, which is defined by the extension of the curved surface 56 in the axial direction of the pivot axis 52. Here, the thickness of the end section 66 is less than half of the maximum thickness of the first lever arm 54, so that, as in Figure 3a , Figure 3b As shown in FIG, the end sections 66 can move past each other during the stapling process without colliding with each other.

[0020] In summary, the following can be determined: the present invention relates to a stapler 10, which is used to bind paper materials together with the help of staplers 12, wherein the staplers respectively have two staple legs 14 and a staple bridge 16 that connects the staple legs 14 to each other and extends transversely to the staple legs, the stapler has an anvil leg 26, the anvil leg has a placement plate 38 for placing paper materials, the anvil leg carries a cutting table 40 with two cutting edges 42, and the cutting edges are used to cut off the excess end portions of the staple legs 14; the stapler has a staple unit 30 that can be pivotally supported relative to the anvil leg 26, the stapler unit has a staple magazine 32 and a driver 36, the staple magazine accommodates the staples 12 in rows with staple bridges 16 that are adjacent to each other and oriented parallel to each other, and the driver 36 The stapler is used to squeeze each staple 12 through the paper material with the free end of its staple leg 14 in front; the stapler has a lower part 18, on which the anvil leg 26 is supported so as to be movable toward the lower part against a restoring force; and the stapler has two double-arm bending levers 50 pivotably supported on the anvil leg 26 about a respective pivot axis 52, the bending levers respectively having a first lever arm 54 and a second lever arm 58, the first lever arm having a bending surface 56 for bending the staple leg 14, wherein, when the anvil leg 26 approaches the lower part 18, the second lever arm 58 pivots about the pivot axis 52 by exerting an action with the aid of the lower part 18, and the bending surface 56 bends the staple legs 14 toward each other and cuts off possible excess end portions by pressing against the cutting edge 42. According to the present invention, the pivot axis 52 extends essentially perpendicularly to the staple bridge 16 of the staple 12 accommodated in the staple magazine 32, and the second lever arm 58 has an end section 66 starting at its free end 64, which is arranged offset from each other in the axial direction of the pivot axis 52 so that the end sections move past each other when the anvil leg 26 approaches the lower part 18.

Claims

1. A stapler, the stapler being used for binding paper materials together by means of a stapler (12), the stapler respectively having two staple legs (14) and a staple bridge (16) connecting the staple legs (14) to each other and extending transversely to the staple legs, the stapler having an anvil leg (26), the anvil leg having a placement plate (38) for placing paper materials, the anvil leg carrying a cutting table (40) having two cutting edges (42), the cutting edges being used to cut off excess end portions of the staple legs (14); the stapler having a staple unit (30) pivotally supported relative to the anvil leg (26), the staple unit having a staple magazine (32) and a driver (36), the staple magazine accommodating staples (12) in rows with staple bridges (16) oriented parallel to each other and abutting against each other, the driver being used to insert each staple (12) into the stapler. ) is pressed through the paper material with the free end of its staple leg (14) in the first place; the stapler has a lower part (18), and the anvil leg (26) is supported on the lower part so as to be movable toward the lower part against a restoring force; and the stapler has two double-arm bending levers (50) which are pivotally supported on the anvil leg (26) about a respective pivot axis (52), the bending levers respectively having a first lever arm (54) and a second lever arm (58), the first lever arm having a bending surface (56) for bending the staple leg (14), when the anvil leg (26) approaches the lower part (18), the second lever arm (58) is pivoted about the pivot axis (52) by applying an action with the help of the lower part (18), and the bending surface (56) causes the staple legs (14) to bend toward each other and cut off excess end portions by pressing against the cutting edge (42), characterized in that The pivot axis (52) extends at an angle of 90°±2° to the staple bridge (16) of the staples (12) accommodated in the staple magazine (32), and each second lever arm (58) has an end section (66) starting at its free end (64), and the end sections are arranged offset from each other in the axial direction of the pivot axis (52) so that the end sections move past each other when the anvil leg (26) approaches the lower part (18), wherein the thickness of the end section (66) measured in the axial direction of the pivot axis (52) is less than the maximum thickness of the first lever arm (54) measured in the axial direction of the pivot axis (52).

2. The stapler according to claim 1, characterized in that: The two curved surfaces (56) have the same extension in the axial direction of the pivot axis (52).

3. The stapler according to claim 2, characterized in that: The first lever arms (54) are arranged mirror-symmetrically to each other about a symmetry plane extending in the middle between the pivot axes (52) perpendicular to the staple bridge (16) of the staples (12) accommodated in the staple magazine (32).

4. The stapler according to any one of claims 1 to 3, characterized in that: The thickness of the end section (66) is at most half the maximum thickness of the first lever arm (54).

5. The stapler according to any one of claims 1 to 3, characterized in that: The pivot axes (52) are arranged at such a distance from one another that the first lever arm (54) can be moved past the cutting edge (42).

6. The stapler according to any one of claims 1 to 3, characterized in that: The placement plate (38) has openings (62) on both sides of the cutting table (40) for the free ends of the nail legs (14) to be guided through after piercing the paper.

7. The stapler according to any one of claims 1 to 3, characterized in that: The curved surface (56) can be pivoted from a resting position to a nailing position when the anvil leg (26) approaches the lower part (18), in which the curved surface is arranged at a positive acute angle to the placement surface (60) on the upper side of the placement plate (38), and in the nailing position, the curved surface is arranged parallel to the placement surface (60) or at a negative acute angle to the placement surface.

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