GB2154926A - Staple magazines and methods of loading magazines - Google Patents

Abstract

To simplify exchange of a loaded magazine for another, a staple magazine for use with staple driving apparatus for ejecting staples (23) at an ejection location (18) comprises an elongate member (21a, 21b) for supporting the staples (23) and engagement means (27) for defining a fully inserted position of the magazine in the apparatus characterised by retaining means (42) arranged to come into retaining engagement with said staples (23) as said magazine is withdrawn from said fully inserted position to hold said staples fixed against longitudinal movement in at least one direction relative to said elongate member (21a, 21b). <IMAGE>

Description

SPECIFICATION Staple magazines and methods of loading magazines The present invention relates to staple magazines and to methods of loading such magazines.

It is well known that in a staple dispensing apparatus, a guideway structure receives a clip of staples thrust forward by a slidable pusher so as to have the leading staple in position for ejection from the apparatus to be driven into a workpiece. The guideway structure for receiving the staples is commonly known as a staple magazine.

Most tools of this nature are designed in such a way as to allow the magazine to be pulled towards the rear of the tool thereby exposing a cavity within the body of the tool for loading staples in clip form. As used in this specification, a clip consists of a plurality of staples joined together by a breakable bond. A pusher, which is usually part of the magazine, is also withdrawn together with the magazine. After the staples are placed into the cavity, the magazine is then pushed back into the tool and latched in a position for driving.

The staples within the magazine are normally forced forward by a spring biasing the pusher.

From a labour-saving standpoint, it is useful to have a staple magazine that holds a large number of staples in order to reduce the frequency of stops for reloading. Often, however, the tool must be held for driving in a position which does not permit such a large magazine. It is furthermore inconvenient with known tools to replace one magazine with another, as will be explained below. This therefore necessitates two separate tools and therefore increases the cost of equipment.

Problems associated with interchanging known magazines are concerned with how to conveniently load the magazine and how to discharge staples from the magazine safely when it is removed from the tool. For loading larger capacity magazines, the method of unlatching the magazine, removing it, retracting the pusher, latching it, opening the magazine, loading, closing the magazine, releasing the pusher, and re-inserting the magazine is inconvenient and time-consuming. When the securing means is released to remove the magazine, the force exerted on the staples by the pusher tends to make the magazine shoot backwards. If caution is not applied, the staples often fly out resulting in breakages or loss of staples. Furthermore, the magazine may eject from the tool and become damaged.

An object of the invention is to provide a staple magazine which can readily be exchanged, e.g. for a magazine of smaller size.

According to one aspect of the invention, there is provided a staple magazine for use with staple driving apparatus for ejecting staples at an ejection location comprising an elongate member for supporting a staple clip and engagement means for defining a fully inserted position of the magazine in the apparatus characterised by retaining means arranged to come into retaining engagement with said staple clip as said magazine is withdrawn from said fully inserted position to hold said clip fixed against longitudinal movement in at least one direction relative to said elongate member.

According to another aspect of the invention, there is provided a method of loading a staple magazine characterised by the following steps: (a) inserting a first staple clip in a receiving cavity of staple driving apparatus; (b) inserting a magazine into said cavity to engage the first clip; (c) withdrawing the magazine with the first clip engaged therewith; (d) inserting a second staple clip in said cavity; (e) inserting the magazine into the cavity whereby the second clip engages the first clip and advances it into the magazine and the second clip becomes engaged with the magazine; and (f) securing the magazine in its fully-inserted position.

A further object of the invention is to provide a magazine in which force from the staple pusher is prevented from being exerted through the staples onto the driving apparatus to prevent the magazine from shooting backwards when the magazine is released.

Another object of the invention is to provide a magazine which can be removed from a staple dispensing apparatus together with the staples without first resetting the pusher to relieve the force against the staples.

For a better understanding of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figure 1 is a side elevational view of a typical staple dispensing apparatus equipped with a magazine according to one embodiment of the invention; Figure 2 is a side elevational view of the magazine with a partial staple clip in retentive position; Figure 3 is a top plan view of the magazine with a partial staple clip in retentive position; Figure 4 is a cross-sectional view along line A-A of Figure 2; Figure 5 is a cross-sectional view along line B-B of Figure 2; Figure 6 is a cross-sectional view along line C-C of Figure 2; Figure 7 is a cross-sectional view along line F-F of Figure 3; Figure 8 is a bottom plan view with the magazine pulled rearwardly for loading;; Figure 9 is a bottom plan view with the magazine pushed forward to charge the magazine with a first staple clip; Figure 10 is a side elevational view with the magazine pulled rearwardly with the first staple clip being retained; Figure 11 is a bottom plan view with the magazine and first clip of staples pulled rearwardly to expose a cavity for inserting a second clip of staples; Figure 1 2 is a side elevational view of a modified magazine for narrow crown staples; Figure 1 3 is a top plan view of the modified magazine; Figure 14 is a partial cross-sectional view along line D-D of Figure 1 5 of a magazine with an alternative design of staple retention device; Figure 1 5 is a cross-sectional view along line B-B of Figure 14; and Figure 1 6 is a side elevational view of a typical standard single clip capacity magazine.

Figure 1 shows a staple magazine 1 5 according to one embodiment of the invention inserted on a typical staple dispensing apparatus 1 6 and held therein by a latch 30. The apparatus 1 6 has a body 1 7 within which air chambers, valves, pistons, drivers, etc., are installed to drive a succession of fasteners one at a time through a driving throat 1 8 into a workpiece. The valves, piston, driver, etc., within the body 1 7 are actuated by a manually operated trigger 1 9 when the tool is connected to a compressed air supply at connector 20. The present invention is applicable also to mechanically operated tools as well as the illustrated pneumatically operated tool.

Referring to Figures 2, 3, 4, 5 and 6, the magazine 15 has a longitudinal member 21 for supporting the under side of crown portions 22 of staples 23. The member 21 can be referred to as a staple guiding rail or bench. Vertical portions 21a are provided for supporting the staples 23. Depending on the size of the crown portions 22, the vertical portion 21a of the rail will differ. The illustrated construction is of U-shape having a base 21b. A channel-member 24 having two transverse and vertically extending portions 24a carries webs 25 parallel to its base 24b at ends of respective extensions 24a and is attached to the rail 21 as a continuation thereof. Although as described and illustrated, the bench is thus constructed of two components 21 and 24, it could also be a unitary formed member, such as, for example, described in previous U.S. Patent No.

4,211,351 in the name of Umberto Monacelli.

The webs 25 are slidably engaged in a locating guideway 26 in the tool as indicated in dash lines in Figure 6. At the front end of the rail 21 is attached a metal inset 27, which provides a portion of the driving throat 1 8 for the staples 23, the front shape of the driving throat 1 8 being wholly conventional.

Intermediate the ends of the channel member 24 is an inverted U-shaped member 28 (Figures 2 and 5) having opposed parallel walls 28a spaced to allow the staples 23 to pass freely therebetween. A web portion 28b connecting the walls 28a has a protrusion 29 shaped to be secured within the tool by engagement with the latch 30.

A cover 31 having generally inverted Ushape is attached to a portion of the channel 24 that normally extends outwardly from the tool as best shown in Figures 2 and 4. A web portion 32 of cover 31 is located above the top of the crown-supporting extensions 21 a of rail 21 such that the staples 23 can pass freely under the cover 31 yet cannot move vertically far enough to become disengaged from the rail 21. Side walls 33 depending from the web 32 contain the staples within the magazine. A tab 34 is attached to the channel 24 with fastener 35 to hold cover 31 in position. Those skilled in the art will appreciate that cover 31 can be constructed of more than one piece and can be attached by different methods with only a portion covering the edge of the crown of the staple 23 for containment of the staples 23 within the magazine.

A suitably shaped pusher 36 (Figures 2 and 3) is slidable on the rail 21 for engaging the end staple 23 of a clip and transporting the staples 23 toward the driving throat 1 8. A spring 37 for biasing the pusher 36 forward is attached at one end to the pusher 36 at a hook 38 and is returned through 1808 about a pulley 39 to be attached at its opposite end to rail 21 by a hook 40. The pulley 39 (Figure 3) is pivotal about a transverse shaft 41 disposed within rail 21.

Figure 7 shows a staple retention device 42 also pivotal about the same shaft 41. An edge portion 43 extends vertically such that when rotated counterclockwise, the edge portion 43 protrudes above the top of rail 21 thereby engaging the underneath side of the crown of the staples 23. A portion 44 opposite the engaging edge 43 extends through a slot 45 in rail 21 and channel 24. Extending laterally from portion 44 is a member 47 which can be actuated, thereby rotating the edge portion 43 clockwise to a position below the top of rail 21. Two pins 46 (best shown in Figure 8) extend from the apparatus 1 6 and have sloped faces to slide under member 47 when the magazine 1 5 is inserted and latched in the apparatus 1 6. The downward force on member 47 rotates the device 42. The staples are thus freed to be tramsported forward by the pusher 36.

Upon releasing securing latch 30, the magazine 1 5 can retract until member 47 is clear of pins 46. A spring 48 biases device 42 counterclockwise until edge 43 contacts the crowns of staples 43 from below. The staples can be lifted vetically only a small distance since the top of the crown is confined by the cavity 49 in the body 1 7 of apparatus 1 6. Since the edge portion 43 is capable of protruding above the top of rail 21 more than the staples 23 can rise, it will engage the staples 23 and hold them in fixed longitudinal relationship with rail 21 as magazine 1 5 is withdrawn toward the rear of apparatus 16.

Referring to Figure 1 2 and Figure 13, a magazine is shown for staples 50 having a crown portion smaller than in the above description. A rail 51 in bar form extends vertically from a channel member 24. The latching member 28, cover 31 and mounting channel 24 are basically the same and perform the same functions as previously described. The pusher 52 and front inset 53 are sized according to the staples 50 to be driven but serve the same purpose as previously described.

The narrowness of the rail 51 prevents the springs 54 for biasing the pusher 52 being conveniently disposed in the rail 51. Therefore spring retaining bars 55 are located outside the rail 51. Ears 56 extending transverse of pusher body 52 are slidable over bars 55 to be acted uon by the springs 54 thus transporting the pusher 52 longitudinally along the rail 51.

A slot 57 is provided vertically through a portion of the rail 51 for receiving the staple retention device 58 and spring 48. The device 58 pivots about a shaft 59 transversely disposed in rail 51 and functions analogously to device 42, previously described with reference to Figure 7, when inserted into staple driving apparatus 16.

Referring now to Figures 8, 9, 10 and 11, the loading of staples 23 is as follows. First, the latch 30 is released. The magazine 1 5 can be pulled rearwardly to expose a staple cavity 49 within the body 1 7 of the apparatus 1 6.

With the apparatus 1 6 held with the cavity 49 upward, a clip of staples 23 can be inserted with the crown portion resting on the bottom surface of the cavity 49. The magazine is then pushed forward into the cavity.

The staple 23 making contact with the edge portion 43 of the staple retention device 42 causes if necessary clockwise rotation of the device until the staples 23 can pass freely over the edge portion 43 as previously described. Then the leading end of the clip of staples 23 engages the front portion of the body 17 within the cavity 49. The rail 21 slides between the legs of the staples 23, and the pusher 36, having essentially the same cross-section as the staples 23, is forced back longitudinally along the rail 21 by the staples 23.

Before the magazine 1 5 is securely latched, it can be pulled rearwardly again. The staple retention device 42 rotates counterclockwise biased by spring 48. The edge portion 43 makes contact with the underneath portion of the crown of the staples 23. The device 42 can rotate a limited amount due to the length of the slot 45 (Figure 7) and the force exerted by the spring 37 holds the staples 23 im position om the rail 21 as the magazine is withdrawn. The staples 23 thus remain in the same longitudinal position on the rail 21 as the magazine 1 5 is pulled rearwardly.

The staple cavity 49 is thus exposed for loading another clip of staples 23. The staples 23 are inserted as previously described. The magazine 1 5 is pushed forward with the rail 21 sliding again between the legs of the new staples 23. Staple retention device 42 again disengages as previously described. As the magazine 1 5 approaches the secured position within the apparatus 16, the member 47 of the device 42 slides over the pins 46 that form a part of the body 1 7. The action of the pins upon the member 47 rotates the edge portion 43 clockwise to clear the staples 23 allowing the staples 23 to be transported normally along the rail 21 into the driving throat 1 8 by the pusher 36 for downward movement therefrom.The securing latch 30 is engaged with portion 29 of member 28 holding the magazine 1 5 in fully inserted position.

Referring to Figures 10 and 16, the magazine 1 5 can be removed for interchangeably inserting a shorter magazine 60 shown generally in Figure 16. The dimensional size and location of the channel 61 and the protrusion portion 62 of the securing member 63 are substantially the same as the corresponding channel 24 and protrusion portion 29 so as to allow interchangeability without modification of the apparatus 16.

Returning to Figures 7 and 10, to remove the magazine 1 5 the securing latch 30 is released. The spring force transmitted through the pusher 36 and staples 23 against the body 1 7 moves the magazine 1 5 backward only slightly. As the staple retention device 42 clears the pins 46, the device rotates coumterclockwise making contact at edge portion 42 with the underneath portion of the crown of staples 23. Simce the device 42 can rotate a limited amount due to the slot 45, the force exerted by the spring 37 is transferred to the device 42. Since the spring force is confined within the magazine 15, the magazine 1 5 does not shoot rearwardly as do previously designed magazines.

A magazine safety clip 64 is removed to allow the magazine 1 5 to be completely pulled from the tool 1 6. If staples 23 still remain in the magazine 1 5 when removal is required, they can be easily held in position by placing the hand over the staples 23 thus holding the staples 23 against the top of the rail 21 and the retention device as the magazine is completely withdrawn from the tool 1 6. The staples 23 can now be safely removed from the magazine if needed since the staples are already in the hand. The magazine 60 of different capacity can now be inserted and the safety clip 64 replaced.

Figures 14 and 15 show a modified version 65 of the staple retention device. The rail 21 and channel 24 are substantially the same as previously described. A shaft 66 transverse to rail base 21 b is pivotally disposed within a metal inset 67 retained by fastener 68. Member 69 has an edge portion 70 extending through slot 71 in the rail vertical extension 21a and is attached to the shaft 66 with a fastener 72. A torsion spring 73 biases member 69 counterclockwise.Shaft 66 extends vertically through the rail base 21b and channel 24 and has a lever 74 attached transversely of end portion of shaft 66 for rotational motion when acted upon by a protrusion on body 1 7, such as the pins 46, when the magazine 1 5 is inserted into the staple dispensing apparatus 1 6. A pulley 39 is pivotal about shaft 66 for supporting the pusher sprimg 37 and functions analogously to that previously described.

When rotated counterclockwise as shown in Figure 14, edge portion 70 protrudes through slot 71 thereby engaging the inside of leg extensions of staples 23. The staples 23 are positioned on rail 21 with their leg extensions overlapping the rail extensions 21a and are held in fixed longitudinal relationship with the rail 21. The operation of magazine 15 and apparatus 1 6 during loading and the interchangeability remain the same as previously described.

It will be clear that the particular configuration of the magazine and its size are a function of the size of the relevant seat in the associated driving apparatus and the form and size of the staples to be dispensed and driven.

Thus, a magazine of larger than normal capacity can be charged with more than one clip of staples by exposing the staple cavity in the normal manner, inserting one clip, closing the magazine without latching and reopening it again for insertion of additional clips without resetting the pusher. The staples are able to pass by the retention device 42 or 72 in one direction as the magazine is moved forward and will be held in the same relative longitudinal position relative to the magazine as the magazine is moved backward for inserting additiomal clips.

Whilst certain presently preferred embodiments of the invention have been described, it is to be understood that the invention is not limited thereto but solely by the scope of the appended claims.

Claims (11)

1. A staple magazine (1 5) for use with staple driving apparatus (16) for ejecting staples at an ejection location (18) comprising an elongate member (21) for supporting a staple clip (23) and engagement means (27,28, 29) for defining a fully inserted position of the magazine in the apparatus (16) characterised by retaining means (42;72) arranged to come into retaining engagement with said staple clip (23) as said magazine is withdrawn from said fully inserted position to hold said clip fixed against longitudinal movement in at least one direction relative to said elongate member (21).

2. A magazine according to claim 1 characterised in that said retaining means (42;72) is arranged to hold said clip against movement towards the staple ejection location (18).

3. A magazine according to claim 1 or 2 characterised in that said retaining means allows movement of said clip in one direction relative to the elongate member (21).

4. A magazine according to any one of claims 1 to 3 characterised by pusher means (36) arranged to push said clip towards said ejection location, said retention means being arranged to hold the clip against the force of said pusher means.

5. A magazine according to any one of the preceding claims characterised in that said elongate member is of sufficient length to accept two clips of staples in series and in that said retaining means allows a first clip to move longitudinally for introduction of a second clip.

6. A magazine according to any one of the preceding claims characterised in that said engagement means comprises a latching member (29) for releasably securing tne magazine at said fully inserted position.

7. A magazine according to any one of the preceding claims characterised by means (47;74) for disengaging said retaining means when said magazine reaches said fully inserted position.

8. A magazine according to claim 7 characterised in that said means (47;74) for disengaging said retaining means are arranged to operate automatically as the magazine reaches its fully inserted position.

9. A magazine according to any one of the preceding claims characterised in that said retaining means comprises a resiliently biased pawl having an edge (43;70) for retaining engagement with said clip.

10. A magazine according to claim 9 when dependent on claim 8 characterised in that said pawl has an extension (47;74) to allow contact with release means (46) of said driving apparatus.

11. A magazine according to claim 9 or 10 characterised in that said pawl is pivotably mounted on said elongate member.

1 2. A magazine according to claim 11 characterised in that said pawl is pivotable about an axis parallel or perpendicular to the staple ejection direction.

1 3. A method of loading a staple magazine characterised by the following steps: (a) inserting a first staple clip in a receiving cavity of staple driving apparatus; (b) inserting a magazine into said cavity to engage the first clip; (c) withdrawing the magazine with the first clip engaged therewith; (d) inserting a second staple clip in said cavity; (e) inserting the magazine into the cavity whereby the second clip engages the first clip and advances it into the magazine and the second clip becomes engaged with the magazine; and (f) securing the magazine in its fully-inserted position.

1 4. A staple magazine substantially as hereinbefore described with reference to the accompanying drawings.

1 5. A method of loading a staple magazine substantially as hereinbefore described with reference to the accompanying drawings.