US3763560A

US3763560A - Cutting pliers

Info

Publication number: US3763560A
Application number: US00323022A
Authority: US
Inventors: E Makkay; J Pesce
Original assignee: RCA Corp
Current assignee: RCA Corp
Priority date: 1973-01-12
Filing date: 1973-01-12
Publication date: 1973-10-09
Anticipated expiration: 1990-10-09

Abstract

A pair of diagonal, wire cutting pliers are provided which include a pair of clipping gripping members resiliently secured to the cutting jaws of the pliers to retain clippings formed when a wire is cut by the pliers.

Description

United States Patent 91 Makkay et a1.

[ CUTTING PLIERS [75] Inventors: Egon J. V. Makkay, New

Brunswick; John J. Pesce, Princeton, both of NJ.

[73] Assignee: RCA Corporation, New York, [22] Filed: Jan. 12, 1973 [21] Appl. No.: 323,022

Related US. Application Data [63] Continuation of Ser. No. 126,796, March 22, 1971,

abandoned.

[52] US. Cl. 30/124 [51] Int. Cl B26b 17/00 [58] Field of Search 30/124, 134, 186, 30/191 [56] References Cited UNITED STATES PATENTS 2,323,497 7/1943 Str out 30 124 41 ink 1 Oct. 9, 1973 8/1955 Liscomb 30/124 X 3/1964 Popek 30/134 FOREIGN PATENTS OR APPLICATIONS 1,036,824 7/1966 Great Britain 30/124 1,912,254 9/1970 Germany 1,443,560 7/1965 France 30/124 Primary ExaminerJames L. Jones, Jr. Assistant ExaminerJ. C. Peters Att0rneyEdward J. Norton et a1.

3 Claims, 6 Drawing Figures CUTTING PLIERS This is a continuation of application Ser. No. 126,796 filed Mar. 22,.1971, now abandoned.

BACKGROUNDOF THE INVENTION This invention relates to cutting pliers, and more particularly, wire cutting pliers.

In the manufacture of electrical apparatus, it becomes necessary during the assembly of the apparatus to provide connections from various terminal elements which include, in the case of printed circuits, the connection of components to a printed circuit board. When the connection or connections are completed, there is usually a superfluous end of the wire remaining. A frequent problem arises when the excessive wire ends have to be removed. Usually the wire erid is clipped with a pair of cutting pliers. However, the clipped end may fly out with some danger to the operator or may fly out and get lost among the electrical apparatus components causing possible subsequent electrical failure. Therefore, these clippings must be removed to prevent them from becoming detrimental to the piece of equipmentJl-IoWever the shorterthe length and diameter of the clipping, the more difficult it' is to retain until an operator may properly discard it.

SUMMARY OF THE INVENTION In accordance with the present invention gripping means are provided" for use witha wire cutting tool: The cutting tool has a pair of pivotally mountedQabdttable cutting jaws, two faces of each jaw being tapered to form a cuttingedge. One of the faces ofeach jaw meets a corresponding face of the other jawforming an angular trough therebetweenwhen the cutting edges are abutted. The gripping means includes a pairof gripping members made of thin springsheet metal and'each mountable on one of the jaws. Each member has a sharp, blade-like gripping edge adjacent and substantially parallel to the cutting edge of the jaw upon which it is-mounted. The gripping edge of each member is part of a face section closely spaced'from and substantially parallel to a tapered jaw face. A shoulder section depends from'the face section and is shaped to form the inember to the shape of the jaw. A tab extends fromthe shoulder section. The tab of each'member is fixedly secured to the corresponding one of the jaws so as to resiliently suspend'the face and shoulder sections from the respective jaw.

IN THE DRAWING FIG. 1 is a plan view of a pair of pliers constructed in accordance with the present invention.

FIG. 2 is a cross-sectional view through the jaws of the pliers of FIG. 1. l

FIG. 3 is a-view similar to that of FIG. 2 showing the jaws of the pliers closed on a wire and'the clipped end of the wire restrained by the gripping members of' the present invention.

FIGS. 4a and b are plan and side views, respectively, while FIG. 40 is a bottom perspective view of one of the clamping members.

DETAILED DESCRIPTION In FIG. 1, a pair of conventional diagonalcutting pliers are shown. A pair of gripping

members

12 and 14 in accordance with the present invention are mounted, respectively, on the cutting jaws l3 and 15 of the pliers l0. Pliers 10 are illustrated to that extent necessary to describe the present invention. Jaws l3 and 15 of the pliers 10 pivot about pivot pin 17 such that the

cutting edges

28 and 29 of the jaws when abutted will cut a wire disposed between the jaws. Only part"of the

handles

20 and 21 are shown. A cross-section through the jaws of the pliers 10 along lines 2-2 in FIG. 1 is illustrated in FIG. 2. In FIG. 2, the pivot axis of

jaws

13 and 15 is shown by arrow 23. The jaws l3 and 15 have

faces

25 and 24, respectively, which are aligned with one another and

second faces

27 and 26 respectively, which taper toward

faces

25 and 24 respectively to form

cutting edges

29 and 28 on the

respective jaws

13 and 15.

In a pair of pliers of the type illustrated, cutting is performed by the abutting sharpened

edges

28 and 29. This cutting is in contradistinction to cutting by apair of shears in which cutting is performed by adjacently sliding surfaces. When jaws l3 and 15 pivot about axis 23, cutting

edges

28 and 29 move coplanar with respect to each other and normal to the picot axis 23. Faces 26 and- 27 are inclined to faces 24 and 25, respectively, to form an angular trough therebetween when the cutting edges are abutted. The angle of

faces

26 and 27 is determined by the strength and cutting characteristics designed for a pair of individual pliers.

Faces

24 and 25 are substantially coplanar such that the pliers can be used to clip a wire as closely as possible from whatever the wire protrudes.

A pair of

spring members

12 and 14 according to the presentinvention are preferably made of stainless steel or othersimilar hard, tough, durable metal and are formed as illustrated inthe Figures. FIG. 4 illustrates the structure of member 12 which is a mirror image of member 14. As illustrated, the members 12 and 14'are provided with

face sections

30 and 40,

'shoulder sections

31 and 51 which depend, respectively, from the face sections and

tabs

32 and 38 which depend, respectively, from the shoulder sections.

Face sections

40 and 30 are formed generally to have the same contour as each of the respective jaw faces 26 and 27 of pliers'lfl'. The intersection of edge 33 and face section 30 forms the gripping edge 7 of member 12, while the intersection of edge 43'and face section 40 forms the gripping edge 8 of member 14, the intersections being formed into sharp blade-like edges.

The face section 30 and shoulder section 31 of member 12 are elongated in the general direction of jaw 13. Section 31 is elongated greater than section 30 to form a tab 32 which depends from section 31 at junction 35 which intersects

longitudinal edges

34 and 39 bounding section 31. Tab 32 is suitably bent at a slight angle to section 31 to permit member 12 to conform to the outer surfaces of the corresponding jaw 13 as shown in FIG. 1. It is to be understood that junction 35 is proillustrated. Tab 32 of the left hand member 12 and tab" 38 of the right hand member 14 are each, respectively, secured to the

corresponding jaws

13 and 15. Conventional means, preferably spot welding, may be used to secure these tabs to the jaws.

Face sections

30, 40 and

shoulder sections

31, 51 of

members

12 and 14, respectively, are spaced closely adjacent the

faces

27 and 26 and

edges

41 and 42, respectively, ofjaws 13 and of the pliers.

Shoulders

31 and 51 are formed over the corresponding jaws parallel and closely spaced to

edges

41, 42 of

jaws

13 and 15. The gripping edges 7 and 8 overhang slightly the

cutting edges

29 and 28 of the jaws, when the jaws are in the open condition. When the jaws have the cutting edges 29, 28 abutting in the closed condition, the overhanging portions of each of the members causes the gripping edges 7 and 8 of the members to be resiliently displaced from the position shown in FIG. 2.

As indicated above,

members

12 and 14 are preferably stainless steel. Additionally, these members are provided with thin cross-sections, for example, preferably 0.005 inches thick. As a result, edges 7 and 8 are provided with hard, knife-like characteristics capable of withstanding repetitive gripping actions without noticeable wear or loss of the knife-like characteristics. The advantage of these knife-like characteristics is that edges 7 and 8, even when slightly pressed against a clipping, will dig or scratch the clipping. This digging or scratching provides the gripping members with a stephold" grip on the clipping rather than merely a static surface friction grip as occurs when one blunt surface is pressed against another blunt surface. When a clipping is thrust in the direction of arrow 23, the angle of attack of

faces

30 and 40 with the clipping causes edges 7 and 8 to dig further into the clipping, increasing the gripping action.

Resilient displacement of each of

members

12 and 14 from their free position in a direction generally normal to arrow 23 by a wire inserted between edges 7 and 8 causes spring tension to be exerted on any clipping by the members when the jaws are closed in the abutting position, thus providing pressure on edges 7 and 8 against the clipping. However, while edges 7 and 8 may be resiliently displaced in a direction normal to arrow 23 to permit a wire to be inserted therebetween, the

configuration of the members prevents resilient displacement of edges 7 and 8 in the direction of arrow 23 permitting the positive gripping of a clipping. That is, forces imparted to face

sections

30 and 40 in the direction of arrow 23 are transmitted to the junction of the tabs and corresponding shoulder sections. The tabs and shoulder sections are not rotatable with respect to each other in the direction of arrow 23 at these junctions therefore providing, resistance to any translation by the members in direction 23. In addition, since the movement of

edges

33 and 43 of the members is limited to a direction generally normal to arrow 23, (

jaws

13 and 15 prevent translation in direction opposite to arrow 23) insertion of a clipping or wire between these edges results in a slightly bowed condition in

face sections

30 and 40. That is, that portion of gripping edges 7 and 8 in direct contact with clipping are displaced in a direction opposite to arrow 23 with respect to the remainder of edges 7 and 8 not in contact with clipping 50 due to the tendency of the members to remain in their original position. This bowed condition increases the angle of attack of

face sections

30 and 40 with clipping 50 as seen in FIG. 3. This bowing condition provides additional resistance to

members

12 and 14 with respect to translation in the direction of arrow 23 in opposition to thrusts by clipping 50 during the cutting action. Thus, the pair of thin resilient spring members in accordance with the present invention are capable of providing high retention forces to a clipping in opposition to thrusts by the clipping in the direction of arrow 23. This combination of resiliency in one direction, rigidity in the other direction, in addition to the digging action, provides an improved wire retaining plier.

FIG. 2 illustrates the normal position of

members

12 and 14, while FIG. 3 shows the position and displacement of gripping

members

12 and 14 with the jaws in the abutting closed condition and a wire clipping 50 disposed between

members

12 and 14. By providing aligned surfaces 24 and 25 a wire clipping can be removed close to an object, for example, a printed circuit board 60, from which the wire protrudes. In this case, a wire 61 is shown protruding through an aperture 62 in board 60, the wire not being connected to board 60. Pliers 10 have been used to clip the protruding end 50 from the wire 61. End 50 is shown substantially in the same relative position as it was just prior to being cut. This position is maintained as a result of the opposed relationship between the two gripping edges 7 and 8 of

members

12 and 14, which relationship provides equal and opposite forces to the clipped end 50, permitting the end 50 to remain in substantially its original unclipped position.

The significance of maintaining the clipping 50 substantially in its original position is that components and other parts wired into a printed circuit board may be operated on in the presoldered condition. In this condition the wires are usually loose. When the ends of the wires are clipped, the clipping action could bend the wire, and thus, move the components as well as the associated leads such as wire 61, disrupting the component and wiring arrangement. According to the invention, since the clipped end is substantially in the same position as it was before the clipping occurred, no motion is imparted by the clipping action to the component (not shown) or its lead 61, and thus relatively little disturbance would be made to the arrangement of unsoldered preset components on a printed circuit board. Further the close proximity of

face sections

30 and 40 of gripping

members

12 and 14, respectively, and therefore, gripping edges 7 and 8, to the cutting edges 28 and 29 permit short clippings to be retained thereby.

Pliers constructed according to the present invention using 0.005 thick

stainless steel members

12 and 14 have retained clippings as short as 0.020 inches which length is a function of the spacing between faces 30 and 40 and

jaws

13 and 15 and the thickness of

members

12 and 14. Such small clippings were impossible to retain using prior art pliers. The present invention is especially useful with very fine gauge wiring such as 20 gauge or smaller wire. It is to be noted that each of gripping edges 7 and 8 of

members

12 and 14 overlap cutting

edges

29 and 28 of

jaws

13 and 15, respectively, thus insuring resilient compression of each of edges 7 and 8 against clipping 50.

The present invention is especially suitable for miniature diagonal cutting pliers having a face of approximately 0.3 inches wide. When the pliers are to be used in extremely narrow and hard to get at locations, the

members

12 and 14 are fabricated to extend over the ends of the cutting jaws. The ends of the jaws and the gripping members secured thereto as described above are then ground flat as shown in FIG. 1. Thus, there is a gripping edge on each of

members

12 and 14 adjacent to the extreme end 70 of the pliers. This advantageously provides improved plier flexibility.

The material from which gripping

members

12 and 14 are made should be sufficiently thin to be resilient, sufficiently thick to provide sharp gripping corners for digging into the clipped portion of the wire, sufficiently strong to prevent permanent deformation when spring loaded during the use thereof, and sufficiently hard to prevent undue wear.

In the Figures, the thickness of the gripping members i is shown enlarged and out-of-scale to better illustrate the gripping edges 7 and 8. In practice, the members are provided with relatively thinner cross-sections as described above.

What is claimed is:

l. Gripping means for use with a wire cutting tool, said tool having a pair of pivotally mounted abuttable cutting jaws, two faces of each jaw being tapered to form a cutting edge, one of the faces of each jaw meeting a corresponding face on the other jaw to form an angular trough therebetween when the cutting edges are abutted, said gripping means comprising:

a pair of gripping members each member being mounted on a separate, different one of said jaws and made of thin spring sheet metal for gripping between said members a portion of a wire cut by the tool,

each member having a sharp-blade-like wire biting edge adjacent and substantially parallel to the cutting edge of the jaw upon which it is mounted, said biting edge being part of a face section closely spaced from and substantially parallel to a tapered jaw face, said member further having a shoulder section shaped to form the member to the shape of the jaw depending from said face section and a tab depending from said shoulder section,

said tab of each of said members being fixedly secured to the corresponding jaw for resiliently suspending said face and shoulder sections from the respective jaw whereby said biting edges are resiliently suspended adjacent said cutting edges to grip a wire disposed between the biting edges.

2. The tool of claim 1 wherein each of said biting edges overlap the corresponding adjacent cutting edge when said jaws are open such that said biting edges are resiliently displaced when the cutting edges are in the closed abutting condition.

3. The tool of claim 1 wherein said shoulder portion is substantially parallel to the pivot axis of said jaws, said tab extending from said shoulder portion substantially parallel to said pivot axis such that said shoulder and face sections resiliently pivot solely about the junction of said tab and said shoulder.

Claims

1. Gripping means for use with a wire cutting tool, said tool having a pair of pivotally mounted abuttable cutting jaws, two faces of each jaw being tapered to form a cutting edge, one of the faces of each jaw meeting a corresponding face on the other jaw to form an angular trough therebetween when the cutting edges are abutted, said gripping means comprising: a pair of gripping members each member being mounted on a separate, different one of said jaws and made of thin spring sheet metal for gripping between said members a portion of a wire cut by the tool, each member having a sharp-blade-Like wire biting edge adjacent and substantially parallel to the cutting edge of the jaw upon which it is mounted, said biting edge being part of a face section closely spaced from and substantially parallel to a tapered jaw face, said member further having a shoulder section shaped to form the member to the shape of the jaw depending from said face section and a tab depending from said shoulder section, said tab of each of said members being fixedly secured to the corresponding jaw for resiliently suspending said face and shoulder sections from the respective jaw whereby said biting edges are resiliently suspended adjacent said cutting edges to grip a wire disposed between the biting edges.