US3598367A

US3598367A - Staple opener

Info

Publication number: US3598367A
Application number: US840305A
Authority: US
Inventors: Bruno Ghibely
Original assignee: Esco Metallwaren Martin Huhnken
Current assignee: Esco Metallwaren Martin Huhnken
Priority date: 1968-11-08
Filing date: 1969-07-09
Publication date: 1971-08-10
Anticipated expiration: 1988-08-10
Also published as: GB1222932A; FR2022834A1; DE1807688A1

Abstract

The staple opener comprises two levers swingably connected near their one ends and having each a pair of peaks at their other ends. A tongue is formed at the end of one lever between the two peaks thereof. The opener is suited for staples of two different sizes. Staples with greater distance between the staple legs can be opened by means of the opposite pairs of peaks. Staples with smaller distance between the staple legs can be opened by means of the tongue and the opposite pair of peaks.

Description

United States Patent [in 3,598,367

[72] Inventor Bruno Ghibely [56] Relerences Cited Ahrenslmrg, Hols i Germany UNITED STATES PATENTS P 840305 2,553,660 5/l95l Levendusky 254/28 ggff 3. 2,940,727 6/1960 Sega] 254/28 [73] Assignee Ego Mfllllymu M -fi "uhnken 3.484.080 l2/l969 Tolliver 254/28 Ahrensburg, Holstein lruckenstr, Primary Examiner-Robert C. Riordon Germany Assistant Examiner- David R. Melton [32] Priority Nov. 8, I968 Attorney-Beaman & Beaman [33] Germany [3 l] P 18 07 688.5

ABSTRACT: The staple opener comprises two levers swingably connected near their one ends and having each a pair of peaks at their other ends. A tongue is formed at the end of one lever between the two peaks thereof. The opener is [541 STAPLE suited for staples of two difi'erent sizes.

9 Chm", 3 Staples with greater distance between the staple legs can be [52] 0.8. CI. 254/28 opened by means of the opposite pairs of peaks. Staples with [51] lnt.Cl l25c "/00 smaller distance between the staple legs can be opened by [50] Field of Search 254/28 means of the tongue and the opposite pair of peaks.

PATENTEI] AUGIOIHYI 3.598367 INVEN'IUR. BY g STAPLE OPENER BACKGROUND or THE INVENTION The invention relates to a staple opener suited for opening sta les of two different sizes. U-shaped staples usually serve to connect sheets of paper with each other in such a manner that they cannot be easily detached. The staples are pressed through the sheets to be connected by means of manually operated stapling machines or by means of machine-operated stapling guns, and the ends thereof are bent on the counter punch of the machine or gun into a position in parallel with the plane of the paper, whereby the staple legs are bentaway from each other or towards each other. The bending is effected under the action of pressure in order to obtain a positive connection between the paper and the staple.

The selected cross-sectional area of the staple wire, for instance round wire, flat wire or bridle .wire is'determined by the thickness and strength of the paper sheets to be connected. The usual paper types such as typewriter, copying, airmail and photographic paper, differ very much from each other by their properties. The dimensions of the staples depend on the number of the sheets of paper to be stapled. v

There are essentially two types of staples available on,the market, namely, a first type of staple with larger dimensions and rectangular cross-sectional area and a second, smaller type of staple with genera y round cross-sectional area.

Methods of loosening the connection of paper sheets stapled by wire staples with the aid of a staple opener are known. With these methods, the staple is not torn out of the paper sheets but the legs of the staple are again bent essentially into their position prior to the stapling operation,"hy the cooperation of two elements of the opener. The staple may then easily be pulled out of the stapling holes in the paper sheets.-

It is the object of the invention to provide a staple opener with the aid of which both large and small staples of any desired cross-sectional areas may be easily opened.

SUMMARY OF THE INVENTION In accordance with the invention, the new staple opener comprises a first and a second lever swingably connected near their one ends by a pivot, a pair of peaks formed on each lever at the other ends thereof, both pairs of peaks being directed substantially toward each other with the distance between both peaks of the first lever being smaller than the distance between the peaks of the second lever and the peak edges facing toward the pivot being sloped to the lever longitudinal direction whereby when approaching the other ends of the levers the peaks overlap each other and the intersection points of cooperating sloped edges move toward the pivot, and a tongue arranged at the other end of the second lever between the front edges of the two peaks thereof with a distance from the peaks adapted for the first lever peaks to engage between the tongue and the second lever peaks the end section of the tom gue being aligned with the front edges of the second lever peaks and at least the center section thereof being curved toward the pivot. When opening large staples the two pairs of peaks cooperate with each other; when opening smaller staples, the tongue cooperates with the peaks of the second lever.

BRIEF DESCRIPTION OF THE DRAWING Fig. 3 shows an end view of the staple opener to illustrate 75 another shape of the tongue.

I 2 DESCRIPTION OF THE PREFERRED EMBODIMENTS The staple opener comprises a second lever 12 having a U- I shaped cross-sectional area, a tongue 14 arranged to stand free between the legs 12a at the front side of this lever 12, a first lever 16 with a smaller U-shaped cross-sectional are and two vaulted

finger grip plates

18 and 20 provided with a corrugated surface and fastened each on a lever.

The levers l2 and 16 are swingably connected by means of a pivot 22 arranged near their one ends. Their other ends are pressed apart from each other until they contact a stop face (not shown) by means of a suitable resilient means 24, for instance, a spiral spring or a plate spring. In the stop position the distance between the cooperating peaks of the two levers is at least equal to the diameter of staple wire. The equally long levers l2 and 16 are rounded off at their working ends with a bend radius being equal to the distance of these ends to the pivot. At the working ends of the levers, the lengths of their legs are steadily shortened in the direction towards the pivot, so that a pair of

peaks

12b and 16b are formed on each of the levers l2 and 16 at the outermost ends thereof. The peaks and the tongue can be hardened.

The tongue 14 is formed with a permanent deflection 14a and is tapered and pointed at its end; it may either be made of a material having the same thickness as the U-shaped lever 12 or be shaped massively with a rectangular cross-sectional area (please see FIG. 2). The faces of the legs of lever 16 extend in parallel with respect to the faces of the legs of lever 12 and the edges or faces, respectively, of the tongue 14 and, when in the working position, are disposed between the last-mentioned faces of lever 12 and edges or faces of tongue 14. The tongue I4 also may have a U-shaped cross-sectional area with points 14h.

When opening large staples, the peaks l2h of the lever 12 are pushed below the staple legs as far as possible from the one staple side. 'lhereupon, the other lever 16 having peaks 16h arranged more closely to each other, is approached by pressure applied to the finger grip plates l8 and 20, against the action of the plate spring 24. The peaks lob then engage beneath the staple legs on the other side thereof. With increasing com pression of the working ends of the levers l2, l6 againstthe action of the spring, the pairs of the

peaks

12b, 16b overlap each other and with increasing overlapping the intersection point of the edges of cooperating legs of the elements l2, 16 takes a greater distance from the front edges of the peaks whereby the staple legs are brought essentially into the position they had before the stapling operation was carried out. When the staple legs are bent off from the surface of the uppermost sheet the staple can be drawn out of the stapling holes from the other side of the sheets.

When opening smaller staples, the tongue 14 cooperates with the smaller opening lever 16. The tapered and pointed tongue is pushed beneath the staple legs as far as possible from one side thereof. After the approach of the element to with the peaks 16!), the staple is pressed onto the deflection Ma of the tongue 14 and simultaneously the legs ofthe staple are pressed against the inner surface of the lever l6 in the neighborhood of the working peaks lob, in so doing, they are essentially bent into their position before the stapling. Finally, the staple will have been guided onto the deflection [40 so much, that it may be pulled out of the last sheet of paper. Same as is the ease with the opening of large staples the pierced holes are not much widened either when opening small staples.

In the embodiment as shown in FIG. 3, of a tongue with U shaped cross-sectional area, the peaks 14h aligned with the 1. Staple opener for two different staple sizes comprising a first and a second lever swingably connected near their one ends by a pivot, a pair of peaks formed on each lever at the other ends thereof, both pairs of peaks being directed substantially toward each other with the distance between both peaks of the first lever being smaller than the distance between the peaks of the second lever and the peak edges facing toward the pivot being sloped to the lever longitudinal direction whereby when approaching the other ends of the levers the peaks overlap each other and the intersection points of cooperating sloped edges move towards the pivot, and a tongue arranged at the other end of the second lever between the front edges of the two peaks thereof with a distance from the peaks adapted for the first lever peaks to engage between the tongue and the second lever peaks, the end section of the tongue being aligned with the front edges of the second lever peaks and at least the center section thereof being curved towards the pivot.

2. A staple opener in accordance with claim I, wherein one of the levers is provided with a stop face limiting the divergent movement of the other lever ends and a spring interposed between the levers presses the latter into their stop position in which the distance between the cooperating peaks of the two levers is at least equal to the diameter of the staple wire.

3. A staple opener in accordance with claim 1, wherein a finger grip plate is fastened at the other end of each lever with the surface of application facing away from the peaks of this lever.

4. A staple opener in accordance with claim 1, wherein the end section of the tongue is pointed.

5. A staple opener in accordance with claim I, wherein the peaks and the end section of the peaks are hardened.

6. A staple opener in accordance with claim I, wherein the tongue has the same thickness of material as the levers.

7. A staple opener in accordance with claim I, wherein the tongue is a plate formed integrally with the second lever.

8. A staple opener in accordance with claim I, wherein the tongue is U-shaped with two peaks.

9. Staple opener for two different staple sizes comprising a first and a second lever with a U-shaped cross-sectional area swingably connected near their one ends by a pivot with their legs facing to each other, the leg distance of the first lever being smaller than the leg distance of the second lever, a peak formed on each leg at the other ends of the levers with both pairs of peaks being directed substantially toward each other and the width of each leg decreasing from its peak along at least a part of the lever length, and a tongue formed at the other end of the second lever between the front edges of the two legs with a distance from both legs adapted for the first lever peaks to engage between the tongue and the second lever peaks, the end section of the tongue being aligned with the front edges of the second lever legs and at least its center section being deflected toward the pivot.

Claims

1. Staple opener for two different staple sizes comprising a first and a second lever swingably connected near their one ends by a pivot, a pair of peaks formed on each lever at the other ends thereof, both pairs of peaks being directed substantially toward each other with the distance between both peaks of the first lever being smaller than the distance between the peaks of the second lever and the peak edges facing toward the pivot being sloped to the lever longitudinal direction whereby when approaching the other ends of the levers the peaks overlap each other and the intersection points of cooperating sloped edges move towards the pivot, and a tongue arranged at the other end of the second lever between the front edges of the two peaks thereof with a distance from the peaks adapted for the first lever peaks to engage between the tongue and the second lever peaks, the end section of the tongue being aligned with the front edges of the second lever peaks and at least the center section thereof being curved towards the pivot.

2. A staple opener in accordance with claim 1, wherein one of the levers is provided with a stop face limiting the divergent movement of the other lever ends and a spring interposed between the levers presses the latter into their stop position in which the distance between the cooperating peaks of the two levers is at least equal to the diameter of the staple wire.

5. A staple opener in accordance with claim 1, wherein the peaks and the end section of the peaks are hardened.

6. A staple opener in accordance with claim 1, wherein the tongue has the same thickness of material as the levers.

7. A staple opener in accordance with claim 1, wherein the tongue is a plate formed integrally with the second lever.

8. A staple opener in accordance with claim 1, wherein the tongue is U-shaped with two peaks.