CONTINUOUS WIRE STAPLER

Abstract: A stapler comprising a spool (6) with a (metallic) wire stock (21) wound thereon, which is formed by a continuous wire. The (metallic) wire is forced to displace forwards by an advancement mechanism (9, 18; 8, 10, 11; 23; 12, 16, 27, 33) and is cut to form a fixed length portion (L) each time the stapler is used. This portion of predetermined length (L) is then bent in an U-shape and stapled on the sheets. The cutting, U-shaping and stapling is performed by a device comprising several interacting parts (40, 41, 42, 43, 45, 46, 54, 58, 70).

Description: Description Continuous wire stapler Technical field The present invention relates to a stapler, which is used to connect together through staples one or more sheets of paper or possibly another kind of material which has such characteristics as to allow its penetration by a staple. Background art Known staplers use staples which are already U-shaped, and which are made of possibly galvanized steel to prevent their oxidation. This system does not guarantee a large autonomy of operation since the staplers must be continuously recharged. Moreover, the staples easily mess up the writing desk if they are not kept in their small box. An object of the present invention is to provide a stapler which uses a spool of continuous (metallic) wire which will be cut and U-shaped by the stapler itself, in order to form a staple, whereafter the staple perforates the sheets and bounds them one to the other. Disclosure of the invention Therefore, the object of the present invention is to increase the autonomy of operation of the stapler, allowing to perform thousands of stapling operations before replacement of said spool . Brief description of drawings The present invention will now be described for illustrative and non- limitative purposes with reference to two preferred embodiments thereof, which are shown in the drawings, wherein: Fig. 1 schematically shows a first embodiment of the stapler and its different mechanisms, according to a side view; Fig. 2 shows a (metallic) wire advancement ring, for causing the advancement of the (metallic) wire which is wound around the spool, towards the cutting, U- forming and stapling device; Fig. 3 shows a second ring which is concentrically mounted on the ring of Fig. 2 and which is included in the advancement and safety device; Fig. 4 shows the hook-shaped guide pulley for causing the wire advancement, pivotally mounted on the ring of Fig. 2, integrally with a small lever shown in Fig. 4 in a front view and in a side view; Fig. 5 is a side view of the front part of the stapler and of its various cutting, bending (shaping) and stapling mechanisms, during the cutting operation of the metallic (wire) ; Fig. 6 is a view similar to Fig. 5, at the end of the U- forming operation of the staple; Fig. 7 is a view similar to Figs. 5 and 6, concerning only the front part of the stapler, at the time the staple has already been inserted and its arms are bent on the lower surface of the sheets; Figs. 8a- 8d show various individual constructive components of the cutting, shaping and stapling mechanism, which are illustrated in their assembled condition in Figs. 5,6,7; Fig. 9 is a lateral schematic view of the stapler, similar to Fig 1, wherein however that part of the ring of Fig. 3 which is slotted and serves as a safety device, has been put in evidence; Fig. 10 is a view showing the ring appearing also in Fig. 3, wherein the detail which is put in evidence is the same drawn in heavy lines in Fig. 9; Fig. 11 is a side view of the metallic wire storage spool, wherefrom the staples are obtained during the steps illustrated in Figs. 5, 6, 7; Figs. 12-25 show a second embodiment of the stapler; in particular Fig. 25 is a perspective view of this stapler, wherein the cartridge is removed. Best mode of carrying out the invention In the figures the same numerals are employed to indicate always the same component . The stapler is provided with two -right and left- sides or flanks 1,1, wherein the side views show only one of them (Figs. 1,9). A lower arm 2 is pivotally mounted at 3 , to both sides 1,1, and is received between those sides 1,1, and a hinge 4 is also provided for connecting the lower arm 2 to a support 5. On the support 5 which is located between the sides or flanks 1,1, there is formed a front space for receiving the cutting, U- forming and stapling device, which will be described hereinafter, and a central space for lodging the spool 6. On the rear part of the support 5, there is pivotally mounted - at 7 - the toothed lever 8 which engages the upper toothed ring 9 (of Figs. 3 and 10) . Between the two sides 1,1, passing through the support 5, there is mounted a pin carried by a runner (slide block) 10, said runner sliding during the stapling, inside the arcuated slot 11 of the support 5. A small arm 12 is pivotally connected to the support 5 at the site 13 and is connected by a pin (14) and slot connection, to the lower arm 2. A spring 15 acts between a fixed point of the support 5 and the toothed lever 8. Said spring 15 is in its rest condition when the stapler is not used, whereas it is tensioned when, by acting simultaneously on the support and on the sides or flanks by the hand, the lower arm 2 approaches the front part of the support 5. The small arm 12, as will be explained afterwards, pushes on a stop 16 movable along its guide, along a straight line, said step being continuously biased by a spring towards the contour of the lower ring shown in Fig. 2. This latter spring (not shown), is in its rest condition when the stop 16 engages the peripheral notch 17 of the lower ring 18, otherwise the spring is in the compressed condition. The stapler comprises a spool 6 of the (metallic) wire, which is shown in Fig. 11, and which has a peripheral closed cylindrical wall 19 with the exception of the location indicated by the numeral 20, where the wire 21 can pass through and be guided inside an appropriate guide (track) , as indicated by the path of the (metallic) wire, 21 in Fig. 1, which path is first arcuated and then horizontal and rectilinear (22) . The cylindrical peripheral wall 19 of the spool 6 prevents the radial expansion of the wire, so that the metallic wire 21 remains inside the spool 6. A helicoidal spring 23 is upperly fixed at the site 24 to the support 5 which is located between the sides 1,1, and lowerly the spring is connected to the protrusion 25 of the lower ring 18. The upper toothed ring 9 is slidingly mounted on the lower ring 18, which also slides around the axis of the spool 6 which is freely rotatable inside the support 5, being mounted inside said space . The stapler is provided with two hook-shaped guide pulleys, one of them being stationary and being indicated by reference 26, and the latter being movable and indicated by reference 27. The hook-shaped guide pulley 26 is rotatably mounted on the support 5 and pushes (through a spring) by its tooth or hook, against the (metallic) wire 21 which may slide along a rectilinear path 22 on the front part of the support 5. In this way the wire 21 is always held in the proper position and cannot move spontaneously; the wire advances (being unrolled from the spool 6) when the wire advancement mechanism - whose operation is described below - is actuated. Referring now to Figs. 2,3 and 4, the movable hook- shaped wheel 27 is rotatably mounted inside its seat 29, on the lower ring 18, as shown in Fig. 3. Moreover, a small lever 28 is integral with the movable hook-shaped wheel, by being mounted on the same axis 30 of this hook-shaped wheel. Therefore, the movable hook-shaped wheel 27 and the small lever rotate at the same time. First of all, a description of the step-by-step advancement device of the (metallic) wire 21 will be given. When the user's hand pushes on the support 5 and simultaneously on the (right and left) sides 1,1, the runner associated with the pin 10 fixed to the sides 1,1, slides along the slot 11 and lifts (moves upwards) the toothed lever 8 which engages the upper toothed ring 9. The latter rotates clockwise, the spring 15 is stretched, and the upper toothed ring 9 rotates until its beat 31 will contact the finger 32 (shown in Fig. 2), and from this time on both rings rotate clockwise. The lower ring 18, while rotating, tensions the spring 23. At a certain time, the stop 16 (whose spring is the compressed condition and biases the stop 16 against the ring 18) will engage the notch (recess) 17 (Fig. 1 and Fig. 2) . In this condition the spring of the stop 16 is at rest. While only the ring 9 is rotating clockwise, that is during the time period in which the beat 31 has not yet reached the finger 32 in order to cause also the rotation of the lower ring 18, the small lever 28 lifts the movable hook-shaped wheel by "climbing" on the cam 33 which is formed by the profile of the lower slot 34 of the toothed ring 9. It can be noted in Fig. 3, that the small lever 28 and the movable hook-shaped wheel 27 have been sketched on the upper toothed ring 9 in order to show the interaction between the cam 33 and the lever 28, even if the elements 27,28 are obviously integrally formed and are pivotally mounted on the seat 29 of the lower ring 18. Since the movable hook-shaped guide pulley lifts almost immediately from the wire 21, due to the lever 28, its movement is not hindered by the wire 21. During this period of time the wire 21 is retained in its position by the stationary hook-shaped wheel 26. Also the movable hook- shaped wheel 27 and the small lever 28 are biased by a spring against the profile of the slot 34 and in particular against the cam 33. During the continuation of the compression action performed by the user's hand on the parts 1,1,5, the front end of the (metallic) wire 21 (portion indicated by reference 22) is cut, formed in an U-shaped configuration, and stapled on the sheets (as described below) . At this time, both sides 1,1 and the support 5 begin their return stroke. The toothed lever 8 descends while the upper toothed ring 9 rotates with it (anti-clockwise) . Since during a first period of time the ring 18 stays still, due to the fact that it is retained by the stop 16 engaged inside the notch 17, the movable hook-shaped wheel "descends" (this effect being due to the small lever 28) along the cam 33 and "hooks" the (metallic) wire 21, by rotating clockwise. At the same time, the lower arm 2, while it descends, moves the small lever 12, and the latter acts by a pressure force to the left (Fig. 1) and disengages the stop 16. Now, since the lower ring 18 is no more retained, it is pulled by the spring 23. Then the movable hook-shaped wheel which has hooked with its tooth the wire 21, drags the latter forwards for a sufficient length to carry out the following stapling operation. Therefore, the advancement (feeding) of the wire 21 occurs during the return stroke of the ring 18, at the end of the stapling operation, to avoid the "collision" between the front end of the wire and the stapling means described hereinafter. Therefore, the advancement of the wire 21 will not be allowed until the staple is fully inserted in the sheets. The cam 33, besides being part of the wire advancement (feeding) device, may therefore be considered a safety device. The cam 33 formed on the upper toothed ring 9, retains the hook-shaped wheel 27 in its lifted position, so that the wire 21 will be "hooked" only after the staple has been stapled. Since the toothed ring 9 is not hindered in its rotation, apart from the end-of-stroke condition where it is stopped by the stop 16, it may freely rotate around the space where the spool 6 is lodged, and since the movable hook-shaped wheel 27 is lifted (during a first time interval) , the wire 21 - which has not yet been hooked - cannot advance (function of the safety device) . Preferably, the wire 21 is made of brass, for example OT 58, having a sufficient length to form about 3000 staples. However, any other kind of metal (alloy) which does not oxidate and has a bad spring back characteristic may advantageously be used. In the following a description will be given concerning the mechanism for bending (forming) in a "U" shape the front part of the wire 21, which is denoted by reference 22; said mechanism is at the same time a cutting and stapling mechanism. The different steps are as follows: cutting, shaping, stapling. In order to better understand the operation of the cutting/U-shaping/stapling device, it is advantageous to describe first the general operation in a rough and brief way. All mechanisms are controlled by the ascent and descent of the sides or flanks 1,1. During the ascent (work step) , the following actions are sequentially performed: - the lower arm 2 is made to approach the support 5; - the wire advancement device is "loaded" (the spring 23 is loaded) ; - the wire is cut; - the wire is shaped (U-shape) in order to form the staple . During the descent path (descent step) of the sides 1,1, the following actions are sequentially executed: - the portion where the cutting and shaping of the staple is performed, gets rid of the punch and the fork (hereinafter described) ; - the lower arm.2 is moved away; - the advancement device of the wire 21 is "triggered" (release of the stop 16) ; - a portion of length L of the wire 21 is fed forwards, which will be used to form the two "vertical" sides of the staple of length 1 1# and the horizontal side of length 1 2 , wherein: L = 21^ + 1 (for example 1-^ = 3 mm, 1, = 8 mm, L = 14 mm) . The mechanism for cutting, U-shaping and stapling the wire portion, comprises two cams formed by slots 40, 41 obtained on the sides or flanks 1, 1. Two pegs 42, 43 are introduced transversally inside both cams formed by the slots 40, 41, and they pass through the stapler body. The upper peg 42 passes through a hole 44 of a U- shaped fork 45; the fork 45 cannot rotate around the peg 42. The lower peg 43 supports a punch 46, whose width (lateral dimension) is slightly less than the inner distance between both arms of the fork 45, so that the punch can slide between both arms of the fork 45. The fork 45 and the punch 46 are received inside the support 5, in its front part, and the two pegs pass through the slots 50, 51 obtained on the support 5. A V-shaped leaf spring 58 (Fig. 8b) is fixed at the sites 52a, 52b to the support 5 and is free to move at its lower end, where it is formed integrally with a rectangular block 53 (Fig. 8d) , which at rest penetrates into a hole obtained on the support 5 , thereby occupying part of the inner space receiving the punch 46 and the fork 45. Fig. 8d shows a cross sectional view of the support 5 (front part), the peg 43, the relative punch 46, which slides inside the support 5, and a slide 54 which is also fastened to the peg 43 but is arranged so as to be able to slide downwards along the central open region 60 (Fig. 8b) of the spring 58; there is also shown the small rectangular block 53 penetrating inside the support 5 through a hole and occupying the lower portion of the space where the punch 46 and the fork 45 can slide . The operation of the cutting, shaping and stapling device is as follows. By means of the first cam 40 obtained on both (right and left) sides 1, 1, the first component which is pushed downwards is the fork 45, which cooperating with the die matrix 70 cuts the wire at the cutting point 71 (Fig. 5) , and continuing its stroke bends the cut wire portion on the small block 53 (Fig. 6) , thereby forming the staple (characteristic U-shape) . At this time the downward stroke of the slide 54 is controlled, said slide being mounted on the same peg 43 supporting the punch 46. The slide 54 forces the small block 53 held in its position by the V-shaped spring 58, to move laterally (arrow F, Fig. 8d) and thereby to move away from the space necessary for the descent of the staple inserting punch 46. The latter is pushed downwards by the second cam formed like a slot 41, and forces the staple 80 - which already has assumed an U- shaped configuration - to perforate the paper sheets and to fold itself (Fig. 7) inside the recess 90 formed on the lower arm 2. The invention has been described with reference to a particular embodiment . A number of modifications may be done without departing from the present inventive concept . Moreover, an external housing will cover the whole mechanism and will protect it from impacts, tampering, and intrusion of substances. According to another embodiment, shown in Figs. 12 to 14, the stapler comprises a wire advancement mechanism which is slightly modified. In this second embodiment there is provided a recharge cartridge 100 including the spool 6' whereon the brass wire 21 is wound, and an extension 101 supporting the hook-shaped wheels; the cartridge 100 is supplied with the wire 21 to be fed already inserted below the hook-shaped wheels 126, 127, one of them (126) being stationary and the other (127) movable . Therefore, while in the first embodiment the stationary hook-shaped wheel 26 was pivoted on the support 5, the stationary hook-shaped wheel 126 is now pivotally mounted on the extension 101, on the axis 102, and is biased by the leaf spring 103 in contact with the (metallic) wire 21 which slides along the path 104 ending on the die matrix 170, and the movable hook- shaped wheel 127 is pivotally mounted on the axis 105 of the runner 106. The element 107 comprises a leaf spring 108 and is integrally formed with the movable hook- shaped wheel 127. In the seat 110 of the runner 106, the spring 108 biases the hook-shaped wheel 127 always against the upper surface of the (metallic) wire 21. A short distance of the path 104 traced by the wire is formed by the guide 190 of the runner 106 itself. The runner 106 is mounted inside the slot formed like an arc of a circle 121. To this end the runner may for instance have a T shaped section which fits on the edges of the slot, on the back side of the runner. It can be observed that the cartridge 100 actually comprises two parts 101 and 6' and that by means of the elastic ring 130 the extension 101 is fixed on the spool 6' in a removable way, and the elastic ring 130 prevents the expansion of the wire 21. The most external end of a protrusion 120 of the runner is fixed in the hole 140 of the ring 118 which is like the lower (non-toothed) ring 18, but does not have in the present case a seat for a movable hook-shaped wheel (hook-shaped guide pulley) . The other features of the ring 118 are identical to those of the previously described ring 18 (first embodiment), that is: the protrusion 125 for the helicoidal spring 123 and the finger 132. The operation for this second embodiment is as follows: the toothed ring 109 rotates (during the work step) clockwise (as previously described) , the beat 131 engages the finger 132 of the ring 118 and the rotation of the latter displaces the runner 106 along the arcuate path of the slot 121, until the stop 116 (Fig. 12) engages the notch 117 shown in Fig. 17. The release of the stop 116, which occurs in the same way as in the first embodiment, causes - by the action of the spring 123 (Fig. 12) , the rapid rotation of the ring 118, and therefore the advancement of the wire due to the hook-shaped wheel 127. Therefore, it can be seen that this second embodiment is modified with respect to the wire advancement device 21. This modification is not negligible under the operational point of view, since it has been observed that in the first embodiment it was difficult for the user to slip the wire below the hook-shaped wheels 26, 27. On the contrary, (in the second embodiment) the recharge cartridge 100 is already supplied in the configuration shown in Fig. 22, which includes the hook-shaped wheels 126, 127. Fig. 19 shows a different shape of the V-shaped leaf spring 158, while Fig. 20 shows a die matrix 170 of this last embodiment which is different from the matrix 70. Figs 14, 15, 16 are schematical representations corresponding to Figs. 5, 6, 7 and do not require particular explanations. Fig. 13 shows a piece of hardened steel and in general of hard metal 200, which is included in the lower arm 2' made of iron. Costs are reduced in this way, since it will not be necessary to realize the whole body of the lower arm 2' by employing hardened steel.

Claims: Claims 1. A stapler comprising two sides or flanks (1,1) supporting a rotatable lower arm (2') which is pivoted by a hinge (4) to a support (5) located between said sides or flanks (1,1), characterized in that it comprises a spool (6') which is freely rotatably mounted on the support (5) and serves for winding thereon a continuos wire (21) used to form the staples; a controlled advancement mechanism of the wire (21) which is formed by a first ring (18) supporting a movable hook-shaped guide pulley (27) and a second ring (9) whose cam (33) lifts the movable hook-shaped guide pulley (27) in the loading step of the controlled advancement mechanism and lowers the same at the beginning of the return step of said mechanism; drive means (8, 10, 11) of said second ring (9) and an elastic means (15) to cause the return of said drive means (8, 10, 11); and a device for cutting, shaping and stapling which includes a cutting means for cutting the wire, an U-shaping means for forming a staple, and an insertion or pushing means for pushing the already formed staple inside the folding recess (90) . 2. A stapler according to claim 1, characterized in that said second ring (9) drags, that is carries with it the first ring (18) immediately after said cam (33), integrally formed on the second ring, has lifted the movable hook-shaped guide pulley, said dragging action being obtained by means of a finger (32) of the first (18) and a beat (31) on the second ring (9) . 3. A stapler according to claim 1 or 2 , characterized in that the lowering of the movable hook- shaped guide pulley (27) in order to hook the metallic wire, is caused by a temporary stop of the first ring (18) which is due to the presence of a stop (16) . 4. A stapler according to claim 1, characterized in that said drive means (8, 10, 11) include a toothed lever (8) which engages a toothed sector of said second ring (9) , and a pin-and-runner assembly (10) which by sliding inside a slot (11) lifts said toothed lever (8) . 5. A stapler according to claim 1, characterized in that the return of the first ring (18) is caused by a spring (23) when the movable hook-shaped wheel (27) is lowered. 6. A stapler according to claims 3 and 5, characterized in that said stop (16) is released by a movable small arm (12) . 7. A stapler according to claim 1, characterized in that said metallic wire (21) cutting means is a U-shaped fork (45) which interacts with a die matrix (70) . 8. A stapler according to claims 1 and 7, characterized in that said means for shaping the staple according to an "U" configuration, comprises a "U" shaped fork (45) which cooperates with a small block (53) . 9. A stapler according to claims 1, 7 and 8, characterized in that the insertion and pushing means comprises a movable punch (46) which slides between both arms of the U-shaped fork (45) . 10. A stapler according to claims 1, 7, 8, 9 characterized in that the control action on the fork (45) , first, and on the movable punch (46) , afterwards, is effected by means of cams which preferably form camlike slots (40, 41) obtained on the sides (1, 1) and in which there are introduced two respective pegs (42, 43) which support the fork (45) and the movable punch (46) . 11. A stapler according to claims 8 and 9, characterized in that it comprises lateral shifting means (54, 58) for said small block (53) . 12. A stapler according to claims 1 to 11, characterized in that all its mechanisms are protected by an external housing. 13. A stapler according to claims 1 to 12, characterized in that said spool (6) has a peripheral cylindrical wall which prevents the radial expansion of the wire (21) . 14. A stapler according to claim 1, characterized in that a stationary hook-shaped guide pulley (26) is always elastically biased against the wire (21) , in order to avoid a possible displacement of the same, when the movable hook-shaped guide pulley is in the lifted condition. 15. A stapler according to claim 1, characterized in that the wire (21) is made of brass. 16. A stapler comprising two sides or flanks (1,1) which rotatably support a lower arm (2') pivoted by a hinge (4) to a support (5) located between said sides or flanks (1,1), characterized in that it comprises a recharge cartridge (100) which is provided with a spool (6') freely rotatable on the support (5) and with an extension (101) which supports a pair of hook-shaped guide pulleys and which is removably connected to said spool; wherein one of said hook- shaped guide pulleys, - the stationary one (126) -, is rotatably mounted on the extension (101) so as to form a means preventing the backward movement of the wire (21) wound around the spool (6') and the other one, - the movable one (127)-, is rotatably mounted on a runner (106) which slides along a guide (121) of the extension itself; said wire advancement mechanism being formed, besides by said movable hook-shaped guide pulley (127) and its runner, also by displacement means for displacing said runner (106) in a first direction during the work stroke of the sides (1,1) and for displacing said runner (106) in an opposite direction during the return stroke. 17. A stapler according to claim 16, characterized in that said displacement means comprise a first ring (118) and a second toothed ring (109) , wherein the toothed ring (109) drags in the clockwise direction the first ring (118) during the work stroke, whereas during the return stroke of the sides or flanks (1,1) the wire (21) is forced to advance by the anticlockwise rotation of the first ring (118) , which is caused by a spring (123) , due to the fact that said first ring (118) is mechanically coupled to said runner (106) . 18. A stapler according to claim 16, characterized in that said extension (101) supporting the hook-shaped guide pulleys comprises a discontinuous elastic ring (130) for the removable connection thereof to a spool (6') and to prevent the expansion of the wire (21) from the spool (6' ) .

Inventors: ARTUSO FERNANDO, ARTUSO, FERNANDO
Applicants: ARTUSO FERNANDO, CARAFA GIOVANNI & C S N C, ARTUSO, FERNANDO, CARAFA GIOVANNI & C. S.N.C.
Application year: 1997
Main classification: B25C5
IPC codes: B25C5