Easy access metal staple stapler

Abstract: The present invention relates to an easy access metal staple stapler (1) comprising a loading body (2) which is provided at the rear thereof with a pair of ears supporting a pivot pin (4) thereon there is pivoted an outer casing (5) including a pressing member (6) operating at the front portion of the loading body and enclosing the loading body pivoted to the pin. In the outer casing there are housed pushing elastic means (21) and a metal staple pushing slider member (20) for pushing the metal staples contained in the loading body while under the loading body there is arranged an abutment member (30) for closing the metal staples. An actuating lever (40) is moreover provided which is pivoted, at an intermediate position thereof, about a pivot pin (42) which is associated with the abutment member, the actuating lever being provided, at its top end, with a hook portion (45) removably coupled to a pressing rol­ ler (46) adapted to generate, as the lever is operated, a rotation of the outer casing and a pressure for ejecting and closing or crimping a metal staple.

Description: The present invention relates to an easy access and maintenance metal staple stapler apparatus. As is known,metal staple staplers of the so-called pliers type,as presently commercially available,are provided with a loading or loader device for housing and guiding the metal staples,which are resiliently biassed or pushed by a slider member toward the front portion of the stapler,thereat a pressing member ejects and closes or crimps the metal staples to be applied. More specifically the loading of the metal staples is generally carried out by introducing,at the stapler rear end,and upon withdrawing the slider member,the metal staples;in other staples,on the other hand,the metal staples are introduced at the front end of the stapler,upon removing from the front the loader. In both staplers,if a metal staple is locked inside the apparatus,it is very difficult to access the inside of the stapler in order to remove the jammed staple. Another drawback of known staplers is that they have a comparatively low metal staple holding capability. Moreover these known staplers are very complex construction-wise and comprise a lot of component parts of difficult and time consuming assembling. Document US-A-2 354 760 discloses a stapler comprising a metal staple loading body provided at the rear thereof with a pair of ears supporting a pivot pin whereon there is pivoted an outer casing including a pressing member operating at the front portion of said loading body and enclosing said loading body pivoted to said pivot pin, said stapler further comprising a member wherein there are arranged resilient pushing means actuating a slider member for pushing the metal staples held in said loading body, under said loading body there being provided an abutment member for crimping said metal staples, an actuating lever being furthermore provided articulated at an intermediate position thereof about a pin associated with said abutment member, said actuating lever being provided, at the top end thereof, with a hook portion removably engageable with a pressing roller. This stapler has a construction which substantially corresponds to the preamble of the enclosed main claim. Document GB-A-660 740 discloses a wire stapling device including a pressing roller moving with a lever and movable with respect to the casing of the stapler. SUMMARY OF THE INVENTION Accordingly, the task of the present invention is to overcome the above mentioned drawbacks of known metal staple staplers by providing a new and novel type of stapler which can be easily and quickly accessed and subjected to maintenance, in particular which can be easily and quickly opened with a complete removing of the metal staple loader from the stapler casing. Within the scope of the above task, a main object of the present invention is to provide such a metal staple stapler which has a very high staple holding capability, while preserving the overall size of a conventional stapler. Another object of the present invention is to provide such a metal staple stapler which can be assembled in a very quick way at a comparatively low cost. According to one aspect of the present invention, the above mentioned task and objects, as well as yet other objects, which will become more apparent hereinafter, are achieved by an easy access metal staple stapler comprising: a metal staple loading body provided at a rear end with a pivot pin on which is pivoted an outer casing including a pressing member adapted to operate at a front end of said loading body; a closure member pivoted to said pivot pin, adapted during use to enclose said loading body and further accommodating resilient pushing means acting on a slider member to push forward metal staples held in said loading body; an abutment member for crimping said metal staples; an actuating lever with a rear handle portion and a front head portion and rotatably connected at a position intermediate said rear and front portions to a pivot pin associated with the abutment member, the head portion of the actuating lever comprising a hook for removably engaging pin means associated with the outer casing in such a way that movement of the actuating lever in one direction about its pivot pin moves the outer casing and the abutment member against each other, characterized in that, the pin means of the outer casing includes a pressing roller slidable along a track connected to the inside of the outer casing through a further pin; the hook of the actuating lever being formed in such a way that the movement of the lever in the opposite direction about its pivot pin serves to disengage the hook from the pressing roller without involving movement of the outer casing towards the abutment member; and resilient return means acting between the outer casing and the sliding pressing roller. BRIEF DESCRIPTION OF THE DRAWINGS Further characteristics and advantages of the present invention will become more apparent hereinafter,from the following detailed description of a preferred,though not exclusive embodiment,of a metal staple stapler according to the invention,which is illustrated,by way of an indicative but not limitative example in the accompanying schematic drawings,in which: figure 1 is a schematic longitudinal cross-sectional view of the stapler according to the present invention; figure 2 is a further longitudinal cross-sectional view illustrating the subject stapler in its opened condition; figure 3 is a cross-sectional view taken along the line III-III of figure 1; figure 4 is another cross-sectional view of the subject stapler,taken along the line IV-IV of figure 1; figure 5 is another cross-sectional view of the subject stapler,taken along the line V-V of figure 1; figure 6 is yet another cross-sectional view of the subject stapler,taken along the line VI-VI of figure 1; figure 7 is yet another cross-sectional view of the subject stapler,taken along the line VII-VII of figure 1. DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to the figures of the accompanying drawings,the metal staple stapler according to the present invention,which is indicated overally at the reference number 1,comprises a metal staple loading body 2,of elongated shape,which,at the rear portion thereof,supports a pivot pin 4 thereon there is pivoted an outer casing 5 which has a substantially U-shaped cross-section. Inside the mentioned outer casing 5, at its front end portion, there is provided a pressing member 6,of blade or sheet like shape, which can be introduced into a front slot or opening 7 formed in the loading body at the end of a guide rail member 8 whereon the metal staples can be applied,as it will be discovered in a more detailed way hereinafter. The mentioned pressing member 6,as is clearly shown in figure 7,consists substantially of a blade member having an enlarged top end portion 6′ which,by means of two legs 6″,is held in its proper position by bracket members 5′ formed on the outer casing 5. Inside said outer casing 5,in particular,there is arranged a closure element 10 which is located above the metal staple loading body,said closure element 10 being also pivoted on the pin 4 and being provided with a front lug 11 which projects and passes through a slot 12 formed through the pressing element 6 rigid with the outer casing 5. By the disclosed coupling,the closure member 10 is able of swinging with respect to the outer casing and is resiliently biassed by a return spring 15 operating between a boss 16,formed on the top portion of the closure element 10 and a centering pin 17 which,preferably,is formed as a single piece on the mentioned outer casing 5. Inside the closure element 10 there are provided resilient means pushing or biassing a slider member 20 which is slidingly guided on the metal staple guide rail member 8,said resilient means consisting preferably of a coil spring 21 which,at one end thereof,has a point fixed on a tab 23,formed on the element or body 10 and extending on a small pulley 24 arranged near the front end portion of the body 10 and connected with the slider member 20. With such an arrangement,the coil spring will subject the slider member 20 to a pulling force so as to push the metal staples,held in the loading body,toward the front end portion thereat there is arranged the slot 7. Moreover,as the stapler is opened,as it will be disclosed in a more detailed way hereinafter,and as is clearly shown in figure 2,the slider member 20 will be automatically caused to return to the rear end portion of the guide rail member 8,thereby allowing for the metal staples to be easily introduced into the stapler. Under the staple loading body 2 there is provided an abutment member,indicated overally at the reference number 30,which,at its rear portion,is associated with a bracket 31 also pivoted on the mentioned pin 4. As shown,the stapler comprises furthermore an actuating lever,indicated overally at the reference number 40 which,at an intermediate position thereof,is pivoted on the pin 42 which is in turn applied to the abutment member 30. On the latter there is provided a slot 60 therethrough there is caused to pass the curved end of a leaf spring 43 which is held in its operating position by the mentioned pin 42 which thus operates also as an affixing member for said spring 43. In this connection it should be pointed out that the pin 42 is provided,at its center portion 42′,with a smaller diameter in order to allow for said leaf spring to be perfectly located and prevent said pin 42 from disengaging (see figure 5). At its top end portion,the actuating lever 40 is provided with a hook portion,indicated at the reference number 45,which is opened at the front so as to removably engage with a pressing roller 46 sliding on a track 47 which is associated,through the pin 61,with the inner surface of the outer casing 5. A further return spring 48 is moreover provided which affects the roller 46 in order to hold it at a withdrawn position,at rest. As is shown,on the actuating lever 40 there are provided abutment legs or tabs 50 which engage with an end of stroke limit member 51,formed on the staple loading body,and adapted to restrain the rotation of the actuating lever in the opposite direction to the staple applying direction. With the disclosed arrangement,as the actuating lever 40 is pressed,the abutment member 30 will be compelled to move nearer to the staple loading body 2,so as to clamp the sheet material to be joined by the metal staples. Then,the roller 46,by sliding on the track 47,causes a lowering displacement with a consequent rotation about the pin 4. Simultaneously,by pressing the pressing member 6 through the track 47,said pressing member is caused to enter the front end portion of the staple loading body 2,thereby a metal staple will be ejected and closed or crimped. As new metal staples are to be loaded in the stapler,the actuating lever 40 will be turned in an opposite direction to the operating direction, so as to disengage the hook member 45 from the roller 46,with the possibility of completely opening the stapler since the outer casing of the stapler,with the closure element 10 associated therewith,will be completely spaced away from the loading body,as is clearly shown in figure 2. Under this condition,a great amount of metal staples can be easily loaded into the stapler and moreover,if required,the stapler can be easily accessed for removing therefrom possible not properly arranged staples. As is shown,the stapler according to the present invention is provided with a guide rail member 8 which is coupled to the loading body 2 by means of a pin 32 which includes a spring 32′. This pin has a head portion 42′ and an intermediate body 42″,having two diameters,respectively smaller at the top portion thereof and greater at the bottom portion thereof,which are coupled by a conical or tapering portion. The greater diameter portion is housed, with a snug tolerance,in a hole formed on the loading body 2 and in a corresponding hole formed in the guide rail 8. At its front portion,the guide rail 8 is provided with an elongated slot 62 therein engages a leg or tab 63 formed by punching and bending a portion of the loading body 2. If a metal staple locks in the stapler,it can be quickly and easily removed by a slight upward pressure on the rear portion 64 of the mentioned guide rail 8. Thus the guide rail will be caused to withdraw so as to spread apart the slot 7 in order to eject the locked in staple. From the above disclosure,it should be apparent that the invention fully achieves the intended task and objects. While the invention has been disclosed and illustrated with reference to a preferred embodiment thereof,it should be apparent that the disclosed embodiment would be susceptible to several modifications and variations,all of which will come within the scope of the invention as defined in the appended claims.

Claims: An easy access metal staple stapler (1) comprising: a metal staple loading body (2) provided at a rear end with a pivot pin (4) on which is pivoted an outer casing (5) including a pressing member (6) adapted to operate at a front end of said loading body (2); a closure member (10) pivoted to said pivot pin (4), adapted during use to enclose said loading body (2) and further accommodating resilient pushing means (21) acting on a slider member (20) to push forward metal staples held in said loading body (2); an abutment member (30) for crimping said metal staples; an actuating lever (40) with a rear handle portion and a front head portion and rotatably connected at a position intermediate said rear and front portions to a pivot pin (42) associated with the abutment member (30), the head portion of the actuating lever (40) comprising a hook (45) for removably engaging pin means (46) associated with the outer casing (5) in such a way that movement of the actuating lever (40) in one direction about its pivot pin (42) moves the outer casing (5) and the abutment member (30) against each other, characterized in that, the pin means of the outer casing (5) includes a pressing roller (46) slidable along a track (47) connected to the inside of the outer casing (5) through a further pin (61); the hook (45) of the actuating lever (40) being formed in such a way that movement of the lever (40) in the opposite direction about its pivot pin (42) serves to disengage the hook from the pressing roller (46) without involving movement of the outer casing (5) towards the abutment member (30); and resilient return means (48) acting between the outer casing (5) and the sliding pressing roller (46). A stapler according to Claim 1 , characterized in that said closure element (10) is arranged above said loading body (2) and is provided, at the front portion thereof, with a lug (11) projecting and passing through a slot (12) formed on said pressing member (6) rigid with said outer casing (5). A stapler according to Claims 1 and 2, characterized in that said stapler further comprises further return resilient means (15) operating between a boss (16), formed at the top end portion of said closure element (10) and a centering pin (17) formed on the inner surface of said outer casing (5). A stapler according to one or more of the preceding claims, characterized in that said resilient pushing means (21) provided in said closure element (10) comprise a coil spring (21) having a fixed point at the rear end portion of said closure element (10) and extending on a transmission pulley (24) arranged at the front portion of said closure element (10) the other end of said coil spring (21) engaging with said slider member (20) which is slidingly engaged in a guide rail (8) for housing the metal staples in said loading body (2). A stapler according to one or more of the preceding claims, characterized in that as said outer casing (5) is opened by rotation with respect to said loading body (2), said slider member (20) is located at the rear portion of said loading body (2). A stapler according to one or more of the preceding claims, characterized in that under said loading body (2) there is provided an abutment member (30) which, at the rear portion thereof, is associated with a bracket (31) also pivoted on said pin (4). A stapler according to one or more of the preceding claims, characterized in that said pivot pin (42) of said actuating lever (40) is applied on said abutment member (30) wherethrough there is formed a slot (60) wherein there is engaged the curved end of a leaf spring (43) held in its operating position by said pivot pin (42 ) affixing said spring (43). A stapler according to one or more of the preceding claims, characterized in that said pivot pin (42) is provided, at a center portion (42') thereof, with a smaller diameter portion adapted to allow said leaf spring (43) to be properly arranged and prevent said pivot pin (42) from disengaging. A stapler according to one or more of the preceding claims, characterized in that said hook portion (45) of said actuating lever (40) is opened at the front thereof. A stapler according to one or more of the preceding claims, characterized in that said actuating lever (40) is provided thereon with abutment legs which engage with an end of a stroke member (51) provided on said loading body (2) adapted to restrain the rotation of said actuating lever (40) in a direction opposite to the actuating direction thereof. A stapler according to one or more of the preceding claims, characterized in that said actuating lever (40) is adapted to cause said abutment member (30) to approach said loading body (2) so as to clamp a sheet to be stapled A stapler according to one or more of the preceding claims, characterized in that said pressing member (6) is adapted to engage with the front end of said loading body (2) so as to eject and crimp a said staple. A stapler according to one or more of the preceding claims, characterized in that said guide rail (8) is coupled to said loading body (2) through a further pin (32) provided with a spring (32') said further pin (32) having a head (42') and an intermediate body (42'') having two different diameter portions, respectively a smaller diameter at the top portion thereof, and a greater diameter at the bottom portion thereof, said different diameter portions being coupled by a tapering portion. A stapler according to Claim 13, characterized in that said further pin (32) is housed, with a snug tolerance, in a hole formed in said loading body (2) and in a corresponding hole formed on said guide rail (8). A stapler according to one or more of the preceding claims, characterized in that said guide rail (8) is provided, at the front portion thereof, with an elongated slot (62) wherein engages a tab (63) formed by punching and bending a portion of said loading body (2).

Inventors: BALMA GIORGIO, BALMA, GIORGIO
Applicants: BALMA CAPODURI & C SPA, BALMA, CAPODURI & C. S.P.A.
Application year: 1989
Main classification: B25C5
IPC codes: B25C5