Stapler

Abstract

To provide a stapler which can suppress floating of a tip of a staple leg binding a paper sheet from the paper sheet.SOLUTION: When a clincher guide 32 is moved to a standby position and a position of a guide surface 31a of a clincher 31 is positioned at a lower end position farthest from a holding section 32a of the clincher guide 32 positioned at the standby position along the direction of an arrow A1 in a stapler, a length L10 between the guide surface 31a of the clincher 31 and the holding section 32a of the clincher guide 32 is 29% or more and 62% or less of a length of a staple leg 11.SELECTED DRAWING: Figure 4A

Description

Technical Field

[0001] The present invention relates to a stapler for stapling paper with a needle.

Background Art

[0002] In a stapler that staples paper by passing the legs of a needle, which is called a staple formed in a U shape, through the paper and bending them on the back side of the paper, there is a magazine for storing the needles, a handle portion provided with a driver for driving the needles stored in the magazine toward the paper, and a clincher portion provided with a clincher for bending the legs of the needles that have been driven out of the magazine and passed through the paper. The magazine, the handle portion, and the clincher portion are rotatably supported at their respective rear ends.

[0003] And there is known a stapler that staples paper in a form called a flat clincher, in which after the legs of the needle have passed through the paper, the legs are bent along the back side of the paper so as to be in close contact therewith. A stapler for stapling paper in the form of a flat clincher includes a clincher guide that supports the paper above the clincher until the legs of the needle pass through the paper, and a slide member that switches the presence or absence of the operation of the clincher guide. By the relative movement of the clincher guide and the clincher, a force is applied to a pair of legs of the needle that has passed through the paper so that they are bent inward toward each other, and a stapler has been proposed in which the legs of the needle are bent from the base portion of the legs of the needle that has passed through the paper (see, for example, Patent Document 1).

[0004] In such a conventional stapler called a flat clincher, a transmission member such as a link extends from the handle portion to the clincher portion between the position where the clincher is provided and the rear end portion where the handle portion and the clincher portion are connected. For this reason, since the paper cannot be inserted in the direction of the rear end portion beyond the link, it is not suitable for application to a stapler in a form called intermediate stapling.

[0005] On the other hand, there has been proposed a stapler configured to rotate about an axis as a fulcrum and press an L-shaped body having a slider function through a sheet of paper (see, for example, Patent Document 2). With such a stapler, it is possible to realize a flat clinch in the form of a center binding.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0007] In the form of binding a sheet of paper with a needle, in the case of a glasses clinch, the needle leg of the needle bends from the root part penetrating the sheet of paper, and the tip is curved toward the sheet of paper. When the sheet of paper is bound in the form of a glasses clinch, the protruding height of the needle leg penetrating the sheet of paper from the sheet of paper becomes high. Therefore, when stacking the bundles of sheets of paper bound with needles, the stacking height becomes high. In addition, for staplers that achieve center binding, those that bind the sheet of paper in the form of such a glasses clinch have been proposed. In the form of center binding, the folded part is bound with a needle. However, when the folded part is bound in the form of a glasses clinch, the protruding height of the needle leg penetrating the sheet of paper from the sheet of paper becomes high, resulting in a decrease in the appearance of the booklet.

[0008] On the other hand, when the sheet of paper is bound in the form of a flat clinch, the protruding height of the needle leg penetrating the sheet of paper from the sheet of paper can be suppressed to be low. Therefore, even when stacking the bundles of sheets of paper bound with needles, it is possible to suppress an increase in the stacking height. However, the tip of the needle leg is likely to float from the sheet of paper. For this reason, when the tip of the needle leg floats when binding the folded part in the form of a flat clinch, the appearance of the booklet deteriorates.

[0009] The present invention has been made to solve such problems, and an object thereof is to provide a stapler capable of suppressing the tip of the stitching needle from floating from the paper when the paper is stitched.

Means for Solving the Problems

[0010] To solve the above-described problems, the present invention includes a needle punching portion that punches out a needle having a pair of needle legs and a needle shoulder portion that connects the ends of the pair of needle legs, a needle leg bending portion that bends the needle legs of the needle punched out by the needle punching portion, and a connecting portion that connects the needle punching portion and the needle leg bending portion so as to be movable in directions approaching and separating from each other. The needle leg bending portion includes a clincher having a guide surface for bending the needle legs, a clamping portion that clamps the paper between the needle punching portion and the clincher, and an opening that exposes the guide surface in the clamping portion. The clincher is supported so as to be movable in a first direction along the direction in which the needle punching portion and the needle leg bending portion approach and separate from each other, and is configured such that the distance between the guide surface and the clamping portion is displaced by moving in the first direction. The guide surface has an inclined portion that inclines inward at a portion where the tip of the needle leg contacts. The clincher penetrates the paper clamped by the clamping portion by the needle punched out by the needle punching portion, and in a state where the tip of the needle leg after penetration contacts the guide surface, the guide surface is located at the lower end position where the distance from the clamping portion is the farthest along the first direction. The lower end position is a position where the tip of the needle leg contacts the guide surface and a gap is formed between the upper surface of the paper clamped by the clamping portion and the needle shoulder portion of the needle. The clincher guide further moves the clamping portion in a direction approaching the guide surface when the needle is punched out and the pair of needle legs of the needle are bent inward, and the needle shoulder contacts the paper and the needle shoulder is pushed in the first direction together with the paper. When the guide surface is at the lower end position with respect to the clamping portion, the distance between the guide surface and the clamping portion is 29% or more and 62% or less of the length of the needle leg. In the needle leg that has penetrated the paper, the needle leg bends from the root portion where it has penetrated the paper, and a bent portion is formed between the root portion and the tip. The needle leg that has penetrated the paper is in a form along the paper from the root portion to the bent portion, and the tip side from the bent portion is a stapler in which the paper is stitched in a form facing the paper.

[0011] In the present invention, when the clincher guide moves in the first direction, the needle legs passing through the paper are pressed against the guide surface of the clincher, and a force is applied to bend the tip sides of the pair of needle legs inward toward each other.

[0012] When the needle legs are inserted into the paper up to the position where the needle shoulders of the needles contact the upper surface of the paper, the bent portion bent earlier is exposed between the root and the tip of the needle legs protruding from the lower surface of the paper. Also, the pair of needle legs pressed against the guide surface of the clincher are bent inward toward each other with the root portions protruding from the lower surface of the paper as fulcrums, and the curved portions of the needle legs are crushed. As a result, the needle legs passing through the paper are in a form that adheres along the back surface of the paper from the root portion protruding from the lower surface of the paper to the bent portion, and the tip side from the bent portion is in a form facing the lower surface of the paper and the paper is stapled.

Advantages of the Invention

[0013] According to the present invention, since the paper is stapled in a form where the tip side from the bent portion of the needle legs passing through the paper faces the lower surface of the paper, it is possible to suppress the tip of the needle legs from floating from the paper as compared with the form of a flat clincher. Also, since the needle legs passing through the paper are in a form that adheres along the back surface of the paper from the root portion protruding from the lower surface of the paper to the bent portion, it is possible to keep the protruding height of the needle legs passing through the paper from the paper low as compared with the form of a glasses clincher.

Brief Description of the Drawings

[0014]

Figure 1A

Figure 1B

Figure 1C

Figure 1D

Figure 1E

Figure 1F

Figure 2

Figure 3A

Figure 3B

Figure 3C

Figure 4A

Figure 4B

Figure 4C

Figure 4D

Figure 4E

Figure 5A

Figure 5B

[0015] Hereinafter, embodiments of the stapler of the present invention will be described with reference to the drawings.

[0016] <Configuration Example of the Stapler According to the Present Embodiment> FIG. 1A is a cross-sectional view of a main part showing an example of a stapler according to the present embodiment, and FIG. 1B is an overall cross-sectional view showing an example of the stapler according to the present embodiment. Further, FIG. 1C is an overall side view showing an example of the stapler according to the present embodiment, FIG. 1D is an overall top view showing an example of the stapler according to the present embodiment, FIG. 1E is an overall bottom view showing an example of the stapler according to the present embodiment, and FIG. 1F is an overall perspective view showing an example of the stapler according to the present embodiment. Furthermore, FIG. 2 is an explanatory view showing an example of a needle used in the stapler according to the present embodiment.

[0017] A needle 10 called a staple as shown in FIG. 2 is known to have a length L1 (outer dimension) of the needle leg 11 of 4.8 mm, a length L2 (outer dimension) of the needle shoulder 12 of 9.48 mm or less, and a thickness L3 of the needle leg 11 and the needle shoulder 12 of 0.30 mm or more. A needle 10 having such dimensions corresponds to a needle called No. 10 defined by JIS. Also, a needle 10 is known to have a length L1 (outer dimension) of the needle leg 11 of 6.0 mm, a length L2 (outer dimension) of the needle shoulder 12 of 12.97 mm or less, and a thickness L3 of the needle leg 11 and the needle shoulder 12 of 0.45 mm or more. A needle 10 having such dimensions corresponds to a needle called No. 3 defined by JIS. Furthermore, a needle 10 is known to have a length L1 (outer dimension) of the needle leg 11 of 6.0 mm, a length L2 (outer dimension) of the needle shoulder 12 of 11.49 mm or less, and a thickness L3 of the needle leg 11 and the needle shoulder 12 of 0.30 mm or more.

[0018] The stapler 1 includes a needle ejecting portion 2 that ejects such a needle 10, a needle leg bending portion 3 that bends a pair of needle legs 11 of the needle 10 ejected by the needle ejecting portion 2, and a connecting portion 4 that connects the needle ejecting portion 2 and the needle leg bending portion 3 so as to be movable in directions approaching and separating from each other.

[0019] In the stapler 1, a direction in which the needle ejecting portion 2 and the needle leg bending portion 3 approach each other by relative movement is referred to as a first direction, and a direction intersecting the first direction is referred to as a second direction.

[0020] The needle ejection unit 2 includes a magazine 20 that houses the needles 10, a driver 21 that ejects the needles 10 housed in the magazine 20, and a handle unit 22 that operates the driver 21. In the needle ejection unit 2, the magazine 20 and the handle unit 22 are rotatably connected with the shaft 23 as a fulcrum.

[0021] The magazine 20 is configured to be able to house a needle connecting body (not shown) to which a predetermined number of needles 10 are connected, and has a needle ejection opening 20a through which the needles 10 separated from the needle connecting body pass, at the front end on the side opposite to the side where the shaft 23 is provided. The magazine 20 also includes a spring 20c that presses the needle connecting body against the magazine front wall 20b via a pusher 20d.

[0022] The driver 21 is attached to the handle unit 22. When the handle unit 22 rotates with the shaft 23 as a fulcrum, the driver 21 moves along the magazine front wall 20b, separates one needle 10 from the needle connecting body, and ejects it from the needle ejection opening 20a.

[0023] The needle leg bending unit 3 includes a clincher 31 having a guide surface 31a for bending the needle legs 11. The needle leg bending unit 3 also includes a clincher guide 32 having a clamping portion 32a that clamps a sheet between the magazine 20 of the needle ejection unit 2 and an opening 32b that exposes the guide surface 31a of the clincher 31 in the clamping portion 32a. Further, the needle leg bending unit 3 includes a slider 33 that is movable between a first position that restricts the movement of the clincher guide 32 in a first direction and a second position that releases the restriction on the movement of the clincher guide in the first direction, and a clincher switch 34 that moves the slider 33 to the second position.

[0024] The clincher 31 has a guide surface 31a having a groove shaped to guide a pair of needle legs 11 of the needle 10 in a direction of bending inward, facing upward, which is one direction facing the needle ejection unit 2, and is attached to the base 30 of the needle leg bending unit 3.

[0025] The clincher guide 32 is provided with a clamping portion 32a facing the magazine 20 of the needle ejection unit 2, and an opening 32b is provided in the clamping portion 32a facing the needle ejection opening 20a of the magazine 20.

[0026] The clincher guide 32 is supported by the base 30 of the pin leg bending part 3 so as to be movable in a rotational motion or a linear motion in the direction of arrow A1 which is the first direction and the direction of arrow A2 opposite to arrow A1. By moving in the first direction, the distance between the clamping part 32a and the guide surface 31a of the clincher 31 is configured to be displaced.

[0027] The slider 33 is an example of a clincher guide operating member, and is supported by the base 30 of the pin leg bending part 3 so as to be movable in a linear motion in the direction of arrow B1 which is the second direction intersecting the first direction and the direction of arrow B2 opposite to arrow B1.

[0028] The clincher switch 34 is provided on the side opposite to the connecting part 4 with the clincher 31 interposed therebetween, and is supported by the base 30 of the pin leg bending part 3 so as to be movable in a linear motion in the direction of arrow A1 (the first direction) and the direction of arrow A2.

[0029] The clincher switch 34 protrudes from the clamping part 32a of the clincher guide 32 toward the pin punching part 2, and includes a pressed part 34a that is pressed through the paper, and an acting part 34b that pushes the slider 33 in the direction of arrow B1 (the second direction) when the clincher switch 34 moves in the direction of arrow A1. The acting part 34b is composed of an inclined surface that is inclined such that the upper side indicated by arrow A2 is closer to the slider 33 and the lower side indicated by arrow A1 is farther from the slider 33 with respect to the moving direction of the clincher switch 34 indicated by arrows A1 and A2.

[0030] The slider 33 includes a part to be acted upon 33a that is pushed by the acting part 34b of the clincher switch 34, and a locking part 33b that moves along the directions of arrows B1 and B2 when the slider 33 moves in the directions of arrows B1 and B2.

[0031] The slider 33 is provided with a driven part 33a opposite to the actuating part 34b of the clincher switch 34 at one end along the moving directions indicated by the arrows B1 and B2. Further, the slider 33 is provided with a locking part 33b having a shape that protrudes in the direction of arrow A2 toward the clincher guide 32 on the surface facing the clincher guide 32.

[0032] The clincher guide 32 includes a locked part 32c that locks with the locking part 33b of the slider 33 and a retracted part 32d into which the locking part 33b of the slider 33 enters.

[0033] The clincher guide 32 is provided with a locked part 32c having a shape that protrudes in the direction of arrow A1 toward the slider 33 on the surface facing the slider 33. Further, the clincher guide 32 is provided with a retracted part 32d that is concave in the direction of arrow A2 opposite to the direction of arrow A1 in which the locked part 32c protrudes, adjacent to the locked part 32c along the direction of arrow B1, on the surface facing the slider 33.

[0034] The clincher guide 32 is biased by a spring 32e in the direction of arrow A2 in which the clamping part 32a approaches the needle punching part 2. The slider 33 is biased by a spring 33c in the direction of arrow B2 in which the driven part 33a approaches the actuating part 34b of the clincher switch 34. The clincher switch 34 is biased by a spring 34c in the direction of arrow A2 in which the pressed part 34a protrudes from the clamping part 32a of the clincher guide 32 toward the needle punching part 2.

[0035] The clincher guide 32 is biased by a spring 32e in the direction of arrow A2 in which the clamping portion 32a approaches the needle punching portion 2, and the state in which the locked portion 32c is locked to the locking portion 33b of the slider 33 is referred to as the standby position of the clincher guide 32. When the clincher 31 is fixed in a predetermined position, with the clincher guide 32 in the standby position, the guide surface 31a of the clincher 31 is at a position retracted in the direction of arrow A1 with respect to the clamping portion 32a of the clincher guide 32. The predetermined position where the clincher 31 is fixed is referred to as the lower end position. Also, when the clincher 31 is configured to move, the clincher 31 is biased by a spring (not shown) in the direction of arrow A2, and with the clincher guide 32 in the standby position, the guide surface 31a is exposed on substantially the same plane as the clamping portion 32a of the clincher guide 32 and is configured to be movable in the direction of arrow A1 when pushed by the needle leg 11 of the needle 10. When the clincher 31 is configured to move, the clincher 31 is configured to be movable to the lower end position in the direction of arrow A1.

[0036] The slider 33 is biased by a spring 33c in the direction of arrow B2 in which the actuated portion 33a approaches the actuating portion 34b of the clincher switch 34, and the locking portion 33b moves to a position facing the locked portion 32c of the clincher guide 32 and the locking portion 33b is locked to the locked portion 32c, and the first position that restricts the movement of the clincher guide 32 in the first direction is referred to as the standby position of the slider 33.

[0037] The clincher switch 34 is biased by a spring 34c in the direction of arrow A2 in which the pressed portion 34a protrudes from the clamping portion 32a of the clincher guide 32 toward the needle punching portion 2, and the state in which the actuating portion 34b does not press the actuated portion 33a of the slider 33, in this example, the state in which the actuating portion 34b is separated from the actuated portion 33a is referred to as the standby position of the clincher switch 34.

[0038] The needle punching portion 2 includes a pressing portion 24 that actuates the clincher switch 34. The pressing portion 24 protrudes in the direction of the needle leg bending portion 3 and is provided on the handle portion 22 facing the pressed portion 34a of the clincher switch 34.

[0039] In stapler 1, the staple ejection part 2 and the connecting part 4 are connected by a connecting member 25, and the staple leg bending part 3 and the connecting part 4 are connected by a connecting member 35. In this example, stapler 1 is configured such that when the connecting member 25 flexes, the staple ejection part 2 and the staple leg bending part 3 move in directions approaching and separating from each other. In order to staple the paper in a so-called middle binding form, the distance L between the clincher 31 at the paper binding position and the connecting part 4 is set so that the clincher 31 faces near the center between one end and the other end of the paper inserted between the staple ejection part 2 and the staple leg bending part 3. Also, in stapler 1, there is no member provided between the clincher 31 and the connecting part 4 that passes between the staple ejection part 2 and the staple leg bending part 3 and transmits movement.

[0040] Stapler 1 is provided with an insertion position regulating part 5 for regulating the insertion position of the paper. The insertion position regulating part 5 is supported so as to be movable along the connecting member 35 in directions approaching and separating from the position (binding position) of the clincher 31 shown in FIGS. 1A and 1B. By inserting the paper to a position where it abuts against the insertion position regulating part 5, the distance from the end of the paper to the binding position can be defined.

[0041] The insertion position regulating part 5 is provided with a dial 50 for fixing the position with respect to the connecting member 35. The dial 50 is provided coaxially with a screw (not shown), connects the left and right sides of the insertion position regulating part 5 on the lower surface side of the connecting member 35, and moves an acting member 51 acting on one side part and the other side part of the connecting member 35 by fastening the screw, sandwiching the connecting member 35 from both the left and right sides of the insertion position regulating part 5. Thereby, by operating one dial 50, the insertion position regulating part 5 can be fixed to and released from the connecting member 35.

[0042] The stapler 1 is provided with an alignment mark 6a indicating the target of the stapling position on the needle punching portion 2, and an alignment mark 6b on the needle leg bending portion 3. The alignment mark 6a is configured by providing a three-dimensional notation by unevenness, a planar notation by printing, etc. on the upper surface of the handle portion 22 in accordance with the position of the clincher 31 shown in FIGS. 1A and 1B. The alignment mark 6b is configured by providing a three-dimensional notation by unevenness, a planar notation by printing, etc. on the upper surface of the base 30 on both the left and right sides of the clincher guide 32 in accordance with the position of the clincher 31 shown in FIGS. 1A and 1B.

[0043] <Operation example of the stapler according to the present embodiment> FIGS. 3A to 3C are cross-sectional views of the main part showing an example of the operation of the stapler according to the present embodiment, and FIGS. 4A to 4E are front views of the main part showing an example of the operation of the stapler according to the present embodiment.

[0044] When the paper P is placed on the clamping portion 32a and the handle portion 22 is pushed in the direction of arrow A1 and the needle punching portion 2 moves in the direction approaching the needle leg bending portion 3, the magazine 20 comes into contact with the paper P. When the handle portion 22 is further pushed in the direction of arrow A1 with the magazine 20 in contact with the paper P, the handle portion 22 rotates with respect to the magazine 20 with the shaft 23 as a fulcrum, and the needle 10 stored in the magazine 20 is driven out from the needle punching outlet 20a by the driver 21. When the needle 10 is driven out from the needle punching outlet 20a with the magazine 20 in contact with the paper P, the needle leg 11 penetrates the paper P. Then, the needle leg 11 that has penetrated the paper P enters the opening 32b of the clincher guide 32.

[0045] The clincher 31 penetrates the paper P in which the pin legs 11 of the pins 10 punched out by the pin punching portion 2 are clamped by the clamping portion 32a of the clincher guide 32. In a state where the tip of the pin leg 11 after penetration is in contact with the guide surface 31a of the clincher 31, the guide surface 31a is located at the lowest end position farthest from the clamping portion 32a along the direction of arrow A1. This lowest end position is a position where the tip of the pin leg 11 is in contact with the guide surface 31a, and a gap L12 is formed between the upper surface of the paper P clamped by the clamping portion 32a and the pin shoulder portion 12 of the pin 10. The clincher guide 32 further moves in a direction approaching the guide surface 31a of the clamping portion 32a when the pin 10 is punched out, the pair of pin legs 11 of the pin 10 are bent inward, and the pin shoulder portion 12 abuts on the paper P and the pin shoulder portion 12 is pushed in the direction of arrow A1 together with the paper P.

[0046] Hereinafter, the details of the above operation will be described. When the slider 33 is in the standby position and the locking portion 33b of the slider 33 is locked to the locked portion 32c of the clincher guide 32, the movement of the clincher guide 32 restricted by the slider 33 and in the standby position, the guide surface 31a of the clincher 31 is farthest from the clamping portion 32a along the direction of arrow A1, and this position is referred to as the lower end position of the clincher 31.

[0047] When the clincher 31 is fixed in the lower end position, if the length between the driver 21 and the guide surface 31a is the same as the length L1 of the pin leg 11, as shown in FIG. 4A, the tip of the pin leg 11 contacts the guide surface 31a. The guide surface 31a is formed with an inclined portion 31b inclined inward at a portion where the tip of the pin leg 11 contacts, and the tips of the pair of pin legs 11 are guided inward of each other.

[0048] When the clincher 31 is configured to move in the direction of arrow A1 pushed by the pin leg 11 of the pin 10, in a state where the tip of the pin leg 11 is in contact with the guide surface 31a, as shown in FIG. 4A, the clincher 31 moves to the lower end position.

[0049] When the clincher 31 is in the lower end position and the tip of the needle leg 11 is in contact with the guide surface 31a, and the needle punching-out portion 2 further moves in the direction approaching the needle leg bending portion 3, the length between the driver 21 and the guide surface 31a becomes shorter than the length of the needle leg 11. When the length between the driver 21 and the guide surface 31a becomes shorter than the length of the needle leg 11, the tip of the needle leg 11 is pressed against the guide surface 31a, and a force is applied to bend the pair of needle legs 11 inward.

[0050] In a state where the clincher guide 32 is in the standby position and before starting to move in the direction of arrow A1, at the timing of the start of the tip bending of the needle leg 11 to which a force is applied to bend the pair of needle legs 11 inward, the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 is less than the length of the needle leg 11.

[0051] The length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing is preferably 29% or more and 62% or less with respect to the length L1 of the needle leg 11.

[0052] Specifically, when the length of the needle leg 11 is 4.8 mm, the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing is preferably 1.2 mm or more and 2.4 mm or less, and more preferably 1.4 mm or more and 2.4 mm or less. Also, when the length of the needle leg 11 is 6.0 mm, the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing is preferably 1.6 mm or more and 3.7 mm or less, and more preferably 1.8 mm or more and 3.7 mm or less.

[0053] In the configuration where the clincher 31 is fixed at the lower end position, the clincher guide 32 and the slider 33 are in the standby position. With the locking portion 33b of the slider 33 locked to the locked portion 32c of the clincher guide 32, the position of the guide surface 31a of the clincher 31 is at the position farthest from the clamping portion 32a of the clincher guide 32 along the direction of arrow A1. The length L10 between the inclined portion 31b that crushes the needle of the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 satisfies the above value.

[0054] And in the configuration where the clincher 31 is fixed at the lower end position, when the tip of the needle foot 11 that has penetrated the paper P reaches the guide surface 31a of the clincher 31, a gap L12 is formed between the upper surface of the paper P clamped by the clamping portion 32a of the clincher guide 32 and the shoulder portion 12 of the needle 10 even during the operation of binding the maximum allowable number of sheets of paper P.

[0055] Also, when the clincher 31 is configured to be pushed by the needle foot 11 of the needle 10 and move in the direction of arrow A1, the clincher guide 32 and the slider 33 are in the standby position. With the locking portion 33b of the slider 33 locked to the locked portion 32c of the clincher guide 32, when the clincher 31 is pushed by the needle foot 11 of the needle 10 in the direction of arrow A1 and moves to the lower end position, the position of the guide surface 31a of the clincher 31 is at the position farthest from the clamping portion 32a of the clincher guide 32 along the direction of arrow A1. The length L10 between the inclined portion 31b that crushes the needle of the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 satisfies the above value. Further, at the above timing, a gap L12 is formed between the upper surface of the paper P clamped by the clamping portion 32a of the clincher guide 32 and the shoulder portion 12 of the needle 10 even during the operation of binding the maximum allowable number of sheets of paper P.

[0056] When the handle portion 22 is further pushed in the direction of arrow A1 and the needle punching portion 2 moves in a direction approaching the needle leg bending portion 3, the needle legs 11 are pressed against the guide surface 31a, and as shown in FIGS. 4B to 4C, the pair of needle legs 11 are bent inward. In this tip bending process of bending the needle legs 11, since the clincher guide 32 is restricted from moving by the slider 33 and is in the standby position, the gap L12 formed between the upper surface of the paper P held by the holding portion 32a of the clincher guide 32 and the needle shoulder portion 12 of the needle 10 decreases.

[0057] Also, when the handle portion 22 is further pushed in the direction of arrow A1 with the magazine 20 in contact with the paper P, the stapler 1 causes the pressing portion 24 to contact the paper P and push the pressed portion 34a of the clincher switch 34 in the direction of arrow A1 through the paper P.

[0058] When the clincher switch 34 is pushed through the paper P by the pressing portion 24, it moves in the direction of arrow A1 while compressing the spring 34c. When the clincher switch 34 moves in the direction of arrow A1, the acting portion 34b contacts the acted portion 33a of the slider 33. Since the acting portion 34b is composed of an inclined surface inclined in a predetermined direction, when the clincher switch 34 moves in the direction of arrow A1 in a state where the acting portion 34b is in contact with the acted portion 33a of the slider 33, a force is generated to push the acted portion 33a in the direction of arrow B1, and as shown in FIG. 3A, the slider 33 moves in the direction of arrow B1 while compressing the spring 33c.

[0059] When the slider 33 moves in the direction of arrow B1, the locking portion 33b moves from the position facing the locked portion 32c of the clincher guide 32 to the position facing the retracted portion 32d. When the locking portion 33b of the slider 33 moves to the position facing the retracted portion 32d of the clincher guide 32, the clincher guide 32 becomes movable in the direction of arrow A1. The movement of the slider 33 is linked to the operation of the needle punching portion 2 moving in the direction approaching the needle leg bending portion 3. By moving the needle punching portion 2 in the direction approaching the needle leg bending portion 3, until the upper surface of the paper P held by the clamping portion 32a comes into contact with the shoulder portion 12 of the needle 10. In this example, as shown in FIG. 4D, when the upper surface of the paper P held by the clamping portion 32a comes into contact with the shoulder portion 12 of the needle 10, the locking portion 33b of the slider 33 moves to the position facing the retracted portion 32d of the clincher guide 32.

[0060] As a result, when the handle portion 22 is further pushed in the direction of arrow A1 with the magazine 20 in contact with the paper P, as shown in FIG. 3C, the clincher guide 32 is pushed through the paper P, and the clamping portion 32a moves in the direction of arrow A1 while compressing the spring 32e.

[0061] When the clincher guide 32 moves in the direction of arrow A1, the paper P and the needle 10 passing through the paper P move in the direction of arrow A1 together with the clincher guide 32. As a result, the needle legs 11 passing through the paper P and bent inwardly at the tip sides as described above are crushed by being pressed against the guide surface 31a of the clincher guide 32, and are bent inwardly with the root portions protruding from the lower surface of the paper P as fulcrums.

[0062] As a result, as shown in FIG. 4E, the needle legs 11 passing through the paper P are in a form along the back surface of the paper P from the root portion protruding from the lower surface of the paper P to the bending portion 11a, and the paper P is stapled in a form with the tip side from the bending portion 11a facing the lower surface of the paper P.

[0063] The relationship between the length of the needle legs and the stapling form is shown in Tables 1 and 2 below.

[0064]

Table 1

[0065]

Table 2

[0066] When the length of the needle foot 11 is 4.8 mm, as shown in Table 1, when the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing is 1.4 mm, the paper P was bound in a form called a pre-bent clincher from 2 sheets to 22 sheets. Further, when the length L10 is 2.2 mm, the paper P was bound in the form of a pre-bent clincher from 2 sheets to 14 sheets. The paper P is PPC paper 64 g / m2 (55 kg).

[0067] The pre-bent clincher is a form in which the needle foot 11 bends from the root part penetrating the paper P, and there are a substantially straight section where the needle foot 11 extends along the paper P and a substantially straight section where the needle foot 11 extends toward the paper P. Specifically, in the needle foot 11 penetrating the paper P, a bent portion 11a is formed between the root part protruding from the lower surface of the paper P to the tip, and the needle foot 11 penetrating the paper P is in a form that closely adheres along the back surface of the paper P from the root part protruding from the lower surface of the paper P to the bent portion 11a, and the paper P is bound in a form facing the lower surface of the paper P on the tip side from the bent portion 11a.

[0068] Accordingly, when the length of the needle foot 11 is 4.8 mm, if the maximum number of sheets of the paper P to be bound is about 14 sheets, when the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing is 1.4 mm or more and 2.2 mm or less, the paper P was bound in the form of a pre-bent clincher.

[0069] On the other hand, when the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing is 1.2 mm, if the number of sheets of the paper P to be stapled is large within the range of the maximum allowable number, the paper P is stapled in the form of the above-mentioned pre-bent clincher. On the contrary, when the number of stapled sheets decreases, the paper P tends to be stapled in a form called a so-called glasses clincher. In this example, when the number of sheets of the paper P to be stapled is 4 or less, the paper P is stapled in the form of a glasses clincher. The glasses clincher is a form in which the needle foot 11 bends from the root portion penetrating the paper P, and the tip becomes curved toward the paper P.

[0070] Also, when the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing is less than 1.2 mm, even if the number of sheets of the paper P to be stapled is large within the range of the maximum allowable number, the paper P is stapled in the form of a glasses clincher. Furthermore, when the number of sheets of the paper P to be stapled is 4 or less, a problem occurs in that the tip of the needle foot 11 bent on the lower surface side of the paper P penetrates the upper surface side of the paper P.

[0071] From the above, when the length of the needle foot 11 is 4.8 mm, in order to staple the paper P in the form of the pre-bent clincher from the minimum number of stapled sheets (2 sheets), it is preferable that the lower limit value of the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing is 1.2 mm, and it has been found that the lower limit value of the length L10 is more preferably 1.4 mm.

[0072] On the other hand, when the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing exceeds 2.2 mm, the number of sheets of paper P stapled in the form of a pre-bent clincher tends to decrease. When the length L10 is 2.4 mm, the paper P is stapled in the form of a pre-bent clincher from 2 to 12 sheets. When the number of stapled sheets exceeds 12, the paper P is stapled in a form called a so-called flat clincher. The flat clincher is a form in which the needle leg 11 bends from the root part penetrating the paper P and becomes linear along the paper P toward the tip. When the length L10 is 3.4 mm, if the number of stapled sheets is 2, the paper P is stapled in the form of a pre-bent clincher, but when the number of stapled sheets exceeds 2, the paper P is stapled in a form called a flat clincher.

[0073] From the above, when the length of the needle leg 11 is 4.8 mm, in order to staple the paper P in the form of a pre-bent clincher, if the maximum allowable number of stapled sheets is 12, it was found that the upper limit value of the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing is preferably 2.4 mm. Also, when the maximum allowable number of stapled sheets is 14, the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing is 2.2 mm. Considering increasing the maximum allowable number of stapled sheets, it was found that the upper limit value of the length L10 is more preferably 2.2 mm.

[0074] When the length of the needle leg 11 is 6.0 mm, as shown in Table 2, when the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing is 1.8 mm, the paper P is stapled in the form of a pre-bent clincher from 2 to 29 sheets. Also, when the length L10 is 2.7 mm, the paper P is stapled in the form of a pre-bent clincher from 2 to 20 sheets.

[0075] Thus, when the length of the stitch leg 11 is 6.0 mm and the maximum number of sheets of the paper P to be bound is about 20 sheets, if the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing is 1.8 mm or more and 2.7 mm or less, the paper P is bound in the form of a pre-bent clincher.

[0076] On the other hand, when the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing is 1.6 mm, if the number of sheets of the paper P to be bound is large within the range of the maximum allowable number, the paper P is bound in the form of the pre-bent clincher. On the contrary, when the number of sheets to be bound decreases, the paper P tends to be bound in the form of a glasses clincher. In this example, when the number of sheets of the paper P to be bound is 4 sheets or less, the paper P is bound in the form of a glasses clincher.

[0077] Also, when the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing is less than 1.6 mm, even if the number of sheets of the paper P to be bound is large within the range of the maximum allowable number, the paper P is bound in the form of a glasses clincher. Furthermore, when the number of sheets of the paper P to be bound is 4 sheets or less, a problem occurs in that the tip of the stitch leg 11 bent on the lower surface side of the paper P penetrates to the upper surface side of the paper P.

[0078] From the above, when the length of the stitch leg 11 is 6.0 mm, in order to bind the paper P in the form of a pre-bent clincher from the minimum number of sheets to be bound (2 sheets), it is preferable that the lower limit value of the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing is 1.6 mm, and it has been found that the lower limit value of the length L10 is more preferably 1.8 mm.

[0079] On the other hand, when the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing exceeds 2.7 mm, the number of sheets of paper P bound in the form of a pre-bent clincher tends to decrease. When the length L10 is 3.0 mm, the paper P is bound in the form of a pre-bent clincher from 2 to 17 sheets. When the number of bound sheets exceeds 17, the paper P is bound in a form called a flat clincher. Also, when the length L10 is 3.7 mm, the paper P is bound in the form of a pre-bent clincher from 2 to 9 sheets. When the number of bound sheets exceeds 9, the paper P is bound in a form called a flat clincher. Incidentally, when the length L10 is 4.4 mm, if the number of bound sheets is 2, the paper P is bound in the form of a pre-bent clincher, but when the number of bound sheets exceeds 2, the paper P is bound in a form called a flat clincher.

[0080] From the above, when the length of the needle leg 11 is 6.0 mm, in order to bind the paper P in the form of a pre-bent clincher, if the maximum allowable number of bound sheets is 9, it was found that the upper limit value of the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing is preferably 3.7 mm. Also, if the maximum allowable number of bound sheets is 17, the length L10 between the guide surface 31a of the clincher 31 and the clamping portion 32a of the clincher guide 32 at the above timing is 3.0 mm. If the maximum allowable number of bound sheets is 20, the length L10 is 2.7 mm. Considering increasing the maximum allowable number of bound sheets, it was found that the upper limit value of the length L10 is more preferably 2.7 mm.

[0081] Note that no member for transmitting movement is provided between the clincher 31 and the connecting portion 4 through the space between the needle punching portion 2 and the needle leg bending portion 3. Thereby, the distance L between the clincher 31 at the binding position of the paper and the connecting portion 4 can be set so that the clincher 31 faces near the center between one end and the other end of the paper inserted between the needle punching portion 2 and the needle leg bending portion 3. Therefore, the paper P can be bound in the form of a so-called middle binding by the form of a pre-bent clincher.

[0082] Figs. 5A and 5B are front views of the main part of a stapler showing a modified example of a clincher. As shown in Fig. 5A, the clincher 31 may be provided with a recess 31c that is recessed in a direction away from the needle punching portion 2 shown in Fig. 1A etc. near the center along the direction of guiding the needle leg 11 on the guide surface 31a, or may be provided with a convex portion 31d that protrudes in the direction of the needle punching portion 2.

Explanation of Reference Numerals

[0083] 1... stapler, 2... needle punching portion, 20... magazine, 20a... needle punching outlet, 20b... front wall of magazine, 20c... spring, 21... driver, 22... handle portion, 23... shaft, 24... pressing portion, 3... needle leg bending portion, 30... base, 31... clincher, 31a... guide surface, 32... clincher guide, 32a... clamping portion, 32b... opening, 32c... locked portion, 32d... retracted portion, 32e... spring, 33... slider (clincher guide operating member), 33a... portion to be acted on, 33b... locking portion, 33c... spring, 34... clincher switch, 34a... portion to be pressed, 34b... acting portion, 34c... spring, 4... connecting portion, 10... needle, 11... needle leg, 11a... bending portion

Claims

1. a needle launching unit that launches a needle having a pair of needle legs and a needle shoulder portion that connects the ends of the pair of needle legs; a needle foot bending unit that bends the needle foot of the needle driven out by the needle driving unit; a connecting portion that connects the needle driving portion and the needle foot bending portion so as to be movable in a direction in which the needle drives the needle and the needle foot bending portion approach each other and move away from each other; The needle foot bending portion is A clincher having a guide surface for bending the needle foot; a clamping section that clamps a paper sheet between the staple driving section and the clamping section; and a clincher guide that has an opening that exposes the guide surface to the clamping section, is supported so as to be movable in a first direction along a direction in which the staple driving section and the staple foot bending section move toward and away from each other, and is configured such that the distance between the guide surface and the clamping section changes as the clincher guide moves in the first direction, The guide surface has an inwardly inclined portion at a portion where the tip of the needle foot comes into contact, The clincher is configured such that the guide surface is located at a lower end position farthest from the clamping unit along the first direction when the staple driven by the staple driving unit penetrates the paper clamped by the clamping unit and the tip of the staple foot after penetration is in contact with the guide surface, the lower end position is a position where the tip of the staple foot contacts the guide surface and a gap is formed between the top surface of the paper clamped by the clamping section and the needle shoulder of the staple, The clincher guide further moves the clamping portion in a direction approaching the guide surface as the staple is driven out, the pair of staple legs of the staple are bent inward, and the staple shoulder portion comes into contact with the paper and is pushed in the first direction together with the paper. When the guide surface is at the lower end position with respect to the clamping portion, the distance between the guide surface and the clamping portion is 29% or more and 62% or less of the length of the needle foot, The staple foot that penetrates the paper is bent from the root part where it penetrates the paper, and a bent part is formed between the root part and the tip. The staple foot that penetrates the paper is in a form that follows the paper from the root part to the bent part, and the tip side of the bent part is in a form that faces the paper, and the paper is bound. Stapler.

2. The clincher is fixed to the needle foot bending portion at the lower end position.

2. The stapler of claim 1.

3. The clincher is supported by the staple foot bending portion so as to be movable along the first direction to the lower end position.

2. The stapler of claim 1.

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