GB2222546A

GB2222546A - Stapler

Info

Publication number: GB2222546A
Application number: GB8919541A
Authority: GB
Inventors: Yoshio Mitsuhashi
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-08-28
Filing date: 1989-08-29
Publication date: 1990-03-14
Anticipated expiration: 2009-08-29
Also published as: GB2222546B; KR900002902A; GB8919541D0; KR950011759B1

Abstract

A hand-operated stapler has a staple magazine (6) in which a staple pusher (12) is disposed slidably. The staple pusher (12) has lower stapler pushing parts (15) and higher engaging lugs (13) extending laterally. The staplor pusher parts (15) are in sliding engagement with positioning guide ridges (11) of the magazine to prevent bars of staples from lifting up, and the lugs (13) are in sliding engagement with motion guide grooves (14) of the magazine. The parts (15) and lugs (13) are concurrently in sliding engagement with ridges (11) and grooves (14) respectively when the pusher is between the ridges (11) and the grooves (14). When the staple pusher (12) retracts to the rearmost position in the magazine, the stapler pusher parts (15) are no longer in engagement with the ridges (11), and a relatively large space is provided in the rear part of the magazine for loading a plurality of bars of staples (2) from above. <IMAGE>

Description

STAPLER This invention relates to a hand-operated stapler for stapling sheets of paper, and more particularly, to a stapler with a simple structure and capable of holding a plurality of bars of interconnected staples in alignment with one another.

Hand-operated staplers have been known which lend themselves to use with bars of U-shaped staples interconnected, as by means of an adhesive, in a readily separable manner. Typically, each bar consists of 50 staples. Usually, two such staple bars are loaded in a row in a staple magazine. Conventionally, when a plurality of staple bars is loaded into the magazine, the ends of the staple bars come out of alignment or come out of the magazine when pushed endwise by a spring-loaded pusher slidably mounted in the staple magazine for pushing the row of staple bars toward its distal end.

Suggestions have been made to overcome this weakness of hand staplers by providing a magazine cover between the magazine and the handle, as disclosed for example in Japanese Utility Model Publication No. 48-19653. This particular prior art device has the upwardly open magazine provided with a magazine cover to prevent the said de-alignment of the staple bars.

Moreover, in order to achieve a good fit between the magazine cover and the magazine, this prior art has protrusions on both side walls of the magazine cover and closing devices comprising indentations and sloping surfaces on both side walls of the magazine. This is to say that the protrusions and the indentations fit together so that the magazine cover can hold down the staple bars to therefore prevent their ends coming out of alignment or coming out of the magazine.

The object of this invention is to provide a handoperated stapler with a simple structure, wherein a plural number of staple bars can be loaded without de alignment in the magazine, even without the provision of a magazine cover.

To these ends, there is provided a hand-operated stapler comprising a handle and a staple magazine pivotably provided at one end of a base, said magazine being adapted to receive a plural number of bars of staple one after another, an anvil for curving a staple and formed on the top of another end of said base, a staple ejector provided in said handle to push said staple from above to pierce the object to be stapled so that said staple is curved on said anvil, a staple pusher to push said bars of staples from behind, and a spring provided so as to push said staple pusher to supply a foremost staple of said staple bars to the position of said staple ejector, said stapler further comprising: positioning guide means formed in a straight line at a front part of said magazine so as to guide said staple pusher and prevent said bars of staples from lifting up; and motion guide means formed discontinuously with and parallel to said positioning guide means, at a rear part of said magazine so as to also guide the sliding motion of said staple pusher; said staple pusher having different first and second portions which are guided by said positioning guide means and said motion guide means, respectively, said stapler pusher being such that the first and second portions are concurrently in sliding engagement with said positioning guide means and said motion guide means, respectively, when the stapler pusher is in the region between said two guide means.

The operation of the stapler of this invention is as follows. First, the handle of the stapler is opened in order to load the staple bars. A tension coil spring causes the staple pusher inside the staple magazine to retreat back a large amount along the positioning guide means and the motion guide means. Because of this, a space is created between the staple pusher and the positioning guide means. The staple bars are then loaded into this space at an angle from above and then the handle is closed so that the staples are pushed by the staple pusher and have their upper portions held in place by the positioning guide means so that they do not come out of alignment or out of the magazine even without a magazine cover.

Through this arrangement, paper can be placed on the anvil in the same way as for a conventional stapler and the handle pressed to staple the papers easily.

Preferred embodiments of this invention will now be described with reference to the accompanying drawings, in which: FIG. 1 is a sectional view of a stapler according to a first embodiment of this invention; FIG. 2A is a perspective view of a magazine of the stapler shown in FIG. 1; FIG. 2B is a sectional view taken along lines IIB IIB of FIG. 2A; FIG. 3 is a perspective view of a base of the stapler of FIG. 1; FIG. 4 is a perspective view of a staple pusher of the stapler of FIG. 1; FIG. 5 is a sectional view of a stapler according to a second embodiment of this invention; FIG. 6 is a perspective view of a staple pusher of the stapler shown in FIG. 5; FIG. 7A is a perspective view of a magazine of the stapler shown in FIG. 6; FIG. 7B is a sectional view taken along section lines VIIB-VIIB of FIG. 7A; and FIG. 8 is a perspective view of a staple pusher of the staple of FIG. 5.

Referring to FIGS. 1 through 4, a first embodiment of this invention will be described. Reference numeral 1 designates a base of the stapler. As can be seen in FIG.

1 and FIG. 3, the base 1 is provided at one end with an anvil 3 to curve the staples 2, and two side walls 4 at the other end of the base. To the rear of these side walls 4 are provided two protruding mounting shafts 5 on the inside of the walls. These mounting shafts 5 are inserted into mounting holes 7 at the rear of a staple magazine 6 to be described later.

Moreover, on the top of and at the rear of the base 1 is mounted a base spring 8 as shown in FIG. 1.

Furthermore, the side walls 4 of the base 1 are provided with lock protrusions 9 on the inside surface of the side walls 4. These lock protrusions 9 lock with lock holes or indentations 10 provided on the both walls of the magazine 6 so that the base 1 and the staple magazine 6 do not move readily relative to each other at the angular position of the engagement of the protrusions 9 and lock indentations 10.

The staple magazine 6 shown in FIG. 2A is normally made of metal plates and is in the form of a long box with the top open. The magazine 6 stores a plural number of staples 2 in staple bar form. Inside the magazine 6 can be loaded a plural number of staple bars each comprising approximately 50 staples interconnected by adhesive. This embodiment can have three such bars loaded.

The inside walls of the magazine 6 have positioning guide means in the form of ridges 11 cut and bent into the magazine 6 as shown in FIG. 2B so as to prevent the staples 2 loaded into the magazine 6 from coming out of alignment. Moreover, towards the rear of the positioning ridges 11 are provided a pair of motion guide means in the form of grooves 14 into which opposite engaging lugs 13 of a staple pusher 12 (described later) are inserted so as to be movable forwards and backwards.

These motion guide grooves 14 are parallel to the positioning ridges 11 but at slightly higher positions.

The upper part of the magazine 6 in the region of the guide grooves 14 is widely opened so that staples 2 can be inserted from above one bar at a time. The staple pusher 12 (FIG. 4) that pushes the inserted staples 2 towards the front end of the magazine have at their bottom staple pushing members 15 that move along the magazine 6. The staple pushing members 15 constitute first guided portions of the staple pusher 12. The top surfaces of the staple pushing members 15 are in contact with said positioning ridges 11 and the staple pusher 12 therefore prevents the staples from coming out of alignment or out of the magazine. The upper part of the staple pushing members 15 has a head member 16 integrally.

The front surfaces 15a of the staple pushing members 15 are the surfaces that are in contact with the rearmost of the staples 2. The upper surfaces of the staple pushing members 15 move along the magazine 6 while being guided by the positioning ridges 11 in the magazine 6.

The rear portion of the head member 16 is provided with the engaging lugs 13. These lugs 13 move forwards and backwards inside the motion guide grooves 14 of the magazine 6. The lugs 13 constitute second guided portions of the staple pusher 12. When a plural number of bars of staples 2 have been inserted in the magazine 6, the lugs 13 are inserted inside the motion guide grooves 14 so that the staple pusher 12 does not move out of the magazine 6 even if the staple pushing members 15 of staple pusher 12 are removed from and not guided by the ridges 11.

Formed on the head member 16 of the staple pusher 12 is an engaging hook 18 that retains one end of a tension coil spring 17. Moreover, to the rear of the staple pusher 12 is formed a reversing elbow 19 that changes the direction of the tension coil spring 17 through approximately 1800.

Next, the handle 20 of this stapler is formed of synthetic resin and is hollow with its underside open.

A known means such as forced insertion is used to fix a handle spring 22 which has a staple ejector 21 at its end, to the upper surface of the inside of the handle 20. On the inside on both sides of the handle 20 are formed mounting protrusions 23 which are engaged with the internal holes 24 of the mounting shafts 5, provided at the rear of the base 1, so that the base 1 and the handle 20 are rotatable relative to each other.

Furthermore, to the front end of said handle spring 22 is provided a hook 25 to which the tension coil spring 17 is connected. One end of the tension coil spring 17 is connected to the hook 18 of the staple pusher 12, the middle portion of the tension coil spring 17 is passed around a reversing elbow 19 and the other end of the tension coil spring 17 is connected to said hook 25.

Accordingly, the tension coil spring 17 always pulls the staple pusher 12 forwards so as to exert pressure on the rearmost of the staples 2 of the plural number of staple bars loaded in the magazine 6.

Moreover, in FIG. 1, 26 is a member made of synthetic resin to fixedly receive the base 1 and 27 is a flat projection provided so that already clinched staples can be removed. A stopper 28 is formed by bending the rear end of the magazine 6 so that the staple pusher 12 cannot slip out of the motion guide grooves 14. 29 is a spring part of the handle spring 22 to return the handle to its former position after a stapling operation has been performed.

In the embodiment of this invention with the configuration described above, opening the handle 20 for loading bars of the staplers 2 pivots the handle 20 upwards around the mounting protrusions 23. With this pivoting action, the tension of the tension coil spring 17 causes the staple pusher 12 to retreat along the positioning ridges 11 and the motion guide grooves 14.

By this action, a space appears between the front surface of the staple pushing members 15 of the staple pusher 12 and the rear end of the positioning ridges 11 so that three bars of staples 2 can be loaded in order through this space. Then, closing the handle 20 causes the force of contraction of the tension coil spring 17 to advance the staple pusher 12 inside the magazine 6. This status shown in FIG. 1 is the status whereby the stapler can be used, and lift of the staples is prevented because the upper surfaces of the staples 2 are in contact with the positioning ridges 11 provided on the inside surface of the magazine 6.

Therefore, if papers are placed on the anvil 3 of the base 1 in the same way as for a conventional stapler and the handle 20 pressed down, the staple ejector 21 will lower to push the bottom ends of a staple 2 in the magazine 6 into the paper to staple it. Releasing the pressure on the handle 20 will then cause the elastic force of the spring part 29 of the handle spring 22 to cause the staple ejector 21 to rise along with the rise of the handle 20. The upper surface of the staples 2 are in contact with the lower surface of the positioning ridges 11 and so remain in the magazine 6 and are pushed forwards by the advance of the staple pusher 12 due to the force of contraction of the tension coil spring 17 so that the stapler is once again in the status whereby use is possible.

The number of staples 2 will be reduced with further stapling and the staple pusher 12 will advance accordingly. Because of this, the lugs 13 of the staple pusher 12 would come away from the motion guide grooves 14 in the magazine 6 but before it does, the staple pushing members 15 of the staple pusher 12 are inserted into and guided under the lower surface of the positioning ridges 11 so that the top surface of the staple pushing members 15 is guided by the positioning ridges 11 so that stapling can be continued until the last of the staples 2 has been stapled.

The following will describe a second embodiment of this invention, with reference to FIG. 5 and FIG. 6.

This second embodiment is larger than the first embodiment and can have four bars of staples loaded into its magazine. Accordingly, the tension coil spring 17 to push forwards the staple pusher 12 is longer than the tension coil spring 17 of the first embodiment, the reversing elbow 19 is provided at the front end of the handle 20, and the hook 18 on the staple pusher 12 and that hooks one end of the tension coil spring 17 is formed on the top surface of the staple pusher 12, while the other hook 25 is provided at the rear end of the handle 20.

As is shown in FIG. 5, one end of the tension coil spring 17 is hooked to the hook 18, the middle part of the spring is passed around the reversing elbow 19 and the other end of the spring is hooked to the hook 25 in the handle 20, whereby the force of contraction of the tension coil spring 17 causes the staple pusher 12 to advance. The explanation for the other parts is omitted as it is essentially the same as for the first embodiment.

FIG. 7A, FIG. 7B and FIG. 8 illustrate another embodiment of the magazine 6 and the staple pusher 12.

In the previously described embodiments, the lugs 13 are provided at the top at the rear of the staple pushing members 15. In this embodiment, the rear ends of the staple pushing members 15 have been extended upwards so that the lugs 13 are provided on the top surface. Since ther-e is a distance between the staple pushing members 15 and the lugs 13, the sides in contact with and that move against the sides of the magazine 6 can be made longer to therefore ensure more stable motion within the magazine 6 when compared to the previous embodiments.

The positioning ridges 11 of the magazine 6 of this embodiment are formed by a bent flange on the inside walls. Furthermore, the inside surface of the magazine 6 has relatively large openings 30 which allow the lugs 13 of the staple pusher 12 to be inserted into the motion guide grooves 14 more easily. The staple pusher 12 is inserted into the magazine 6 from above so that the pair of lugs 13 are aligned in the magazine 6 in the direction of its length. Then, the staple pusher 12 is rotated through 90" so that the lugs 13 enter the openings 30 respectively and then pulling up the staple pusher 12 in that status inserts the lugs 13 into the motion guide grooves 14.

The invention as described above produces the following effects. First, magazine covers have been provided conventionally in order to prevent the ends of the staple from coming out of alignment and lifting in the magazine in staplers which are loaded with a plural number of staple bars, but it is not necessary to have such a magazine cover in this invention.

Second, the magazine covers of conventional staplers which are loaded with a plural number of staple bars were likely to lift up and release many staples when such staplers are either used or moved but no such phenomena occurs with the stapler of this invention.

Third, the mechanism of the stapler of this invention is simple and so the assembly and adjustment processes are also simplified to provide cost reductions and a better product at the same time.

Fourth, it is possible to increase the work efficiency as the stapler can be operated with more loaded staples than a conventional stapler.

Claims

1. A hand-operated stapler comprising a handle and a staple magazine pivotably provided at one end of a base, said magazine being adapted to receive a plural number of bars of staple one after another, an anvil for curving a staple and formed on the top of another end of said base, a staple ejector provided in said handle to push said staple from above to pierce the object to be stapled so that said staple is curved on said anvil, a staple pusher to push said bars of staples from behind, and a spring provided so as to push said staple pusher to supply a foremost staple of said staple bars to the position of said staple ejector, said stapler further comprising: positioning guide means formed in a straight line at a front part of said magazine so as to guide said staple pusher and prevent said bars of staples from lifting up; and motion guide means formed discontinuously with and parallel to said positioning guide means, at a rear part of said magazine so as to also guide the sliding motion of said staple pusher; said staple pusher having different first and second portions which are guided by said positioning guide means and said motion guide means, respectively, said stapler pusher being such that the first and second portions are concurrently in sliding engagement with said positioning guide means and said motion guide means, respectively, when the stapler pusher is in the region between said two guide means.

2. The hand-operated stapler according to claim 1 wherein said positioning guide means are ridges formed on side walls of the staple magazine.

3. The hand-operated stapler according to claim 1 wherein said motion guide means are grooves formed on side walls of the staple magazine.

4. The hand-operated stapler according to claim 2 wherein the first portions of the staple pusher are stapler pushing parts provided on the two lateral sides of the staple pusher, the stapler pushing parts having top surfaces for sliding engagement with said positioning ridges.

5. The hand-operated stapler according to claim 3 wherein the second portions of the staple pusher are engaging lugs extending laterally for sliding engagement with the motion guide grooves.

6. The hand-operated stapler according to claim 1 wherein said second portions of the stapler pusher and said motion guide means are disposed at positions higher than said first portions of the stapler pusher and said positioning guide means with respect to the direction of depth of the staple magazine.

7. The hand-operated stapler according to claim 1 wherein said staple magazine has a width for allowing the staples to be loaded therein in the region of the motion guide means.

8. The hand-operated stapler according to claim 5 wherein the staple magazine has openings in the side walls thereof in the region of the motion guide grooves, the openings being for facilitating insertion of the engaging lugs into the motion guide grooves.

9. A hand-operated stapler substantially as described herein with reference to and as illustrated in Figures 1 to 4 of the accompanying drawings.

10. A hand-operated stapler substantially as described herein with reference to and as illustrated in Figures 5 to 8 of the accompanying drawings.