US2942341A - Hand shears, scissors and like tools - Google Patents

Description

1-1.. a. RANDOLPH. "HAND 'SHEARS}, YSCISSORS AND LIKE TOOLS 2 Sheets-Sheet 1 File d Jan. 9 1959 June 28; .1960 H. B. mam; 2,942,341

HAND SHEARS'; sd I ssoRs AND LIKE TOOLS med Jan. 9,1959 v I r 2 Sheets-Sheet 2 ATroRNEY United States Patm F r 2,942,341 HAND SHEARS, SCISSORS AND LIKE TOOLS Harry Beckham Randolph, 16 Pall Mall, London, England Filed Jan. 9, 1959, Self. No. 785,854

8 Claims. 01. 30-266) This invention relates to improvements in hand shears, scissors and like tools. 7 g

In particular the invention relates to tools of the kind comprising two co-operating members which are relatively movable about a connecting pivot under the control of associated handles for effecting a cutting, shearing or like action.

According to the present invention there is provided a tool of the kind specified which comprises non-resilient means secured .to one of the handles at a position offset toone side of the connecting pivot for opposing separation of the co-operating members in a direction parallel to thepivotal axis, said non-resilient means overlapping a portion of the co-operating member secured to the other one of the handles, or overlapping the otherone of the handles at a portion thereof where, said other one of the handles overlaps the co-operating member to whichit is secured.

The invention also provides a tool of the kind specified which comprises in addition to the connecting pivotat least one freely rotatable member mounted in one handle, or in the root of the one co-operating member secured thereto, a portion of said rotatable member overlapping or being interleaved with the other handle, or the root of the other co-operating member, whereby said rotatable member opposes separation of said co-operating members in a direction parallel to the pivotal axis.

As is well known, the operative movement of cutting or shearing members is such that a reaction is produced in a direction inclined to the plane of the cut, which reaction tends to cause lateral separation of the cutting or shearing members, resulting in a ragged cut or even in jamming of the members. In conventional cutting tools such separation is only opposed by the connecting pivot, which commonly comprises a bolt and nut. Thus, the provision of additional means opposing such separation, and spaced from the pivot, means that the tool is able to cut or shear through thicker or tougher material without undue separation of the members whilst giving a clean and unbruished cut;

Two constructions of tools in accordance with the inthese particular tools being hand pruning shears. These two constructions will be described with referenceflto the accompanying drawings in which:

Figure 1 is a side view of one construction, and

Figure 2 is a sectional view along the line 11-11 in Figure 1;

Figures 3 and 4 are side elevations of opposite sides refipectively of the second construction of pruning-shear, w ilst Figure 5 is a sectional view taken along the line V--V in Figure 3.

Referring firstly to Figures 1 and 2, it will be seen that in this construction the pruning shear has one blade secured'to an extension 11a of a handle 11 which is of dog-leg shape so that the cutting blade 10 is offset from the hand grip portion of the handle. The co-.

I Patented June 28, 196.0

operating blade 12 is not formed with a sharp cutting edge, but is adapted to bear upon the piece being sheared whilstthe cutting blade 10 slices through the piece. This second blade 12 is mounted on an extension 13a of a handle 13 which is of generally similar shape to the handle 11. The combined thickness of the handle extensions lla, 13a and the roots 10a, 12a of the blades 10, 12 is substantially equal to the thickness of the main portion of the handles 11 or 13 as can be seen from Figure 2. The two handles 11 and 13 are secured together by a pivot bolt 14 having a nut 15 which is not fully tightened on the bolt 14 but is locked thereto by a toothed washer 16 so that both are relatively free to rotate together in the bolt hole, such an arrangement giving in effect a floating fulcrum. The pivotal axis is offset to one side of an imaginary line which bisects the angle between the handles 11 and 13, whereby a rolling cut is obtained.

The dog-leg formation of the handles '11 and 13 is such that not only do the roots 10a, 12a ofthe blades 10 and 12 bear against one another in .the vicinity of the pivot bolt 14, but they also bear against one another in an area spaced from the pivot and lying roughly along a line bisecting the. angle between the working edges of the blades 10 and 12. Moreover, as shown in Figure 2 part of the root, 12a of the blade 12 bears against the handle 11 at the surface 11b. As is explained above, the shearing action tends to cause lateraldisplacement or separation of the shearing members which is, of course,

opposed by the pivot bolt 14. However, according to the invention, such displacement is further opposed by resisting such lateral separation in the neighbourhood of the aforesaid bearing area.

- For this purpose a second bolt 17 is provided which is the head of the bolt 17 overlaps the root 12a of the blade 12 whose outer edge is radiussed about the axis of the pivot bolt 14 so that its edge remains under the head of the bolt 17v throughout the range of opening of the blades.

The bolt 17 thus serves to assist the pivot bolt 14 in opposing separation of the blades 10 and 12 in a direction parallel to the pivotal axis.

The" drawings also show a coil spring 20 each end of which is secured to one handle portion 11a, 13a respectively in order to urge the handles 11, 13 apart in the usual way.. A thumb operated catch 21 is provided for securing the handles 11, 13 in the closed position. Referring now to Figures 3 to 5 these show the second construction in which extensions 31a and 33a. of. handles 31 and 33 respectively are secured to a central pivot .34 and two bolts 24 and 25 are provided to serve the same purpose as the bolt 17 in the previous construction. The bolt 24 is secured by a nut 26 and toothed Washer 27 'whilstthe bolt 25 is similarly secured by a nut 23 and toothed washer 29, both bolts being free to .turn about their respective axes. The head of the bolt 24 overlaps the root 32a of the blade 32, the edge of which is radiussed about the axis of the pivot 34, and the head of the bolt 25 overlaps the root 30a of the blade 30 which is similarly radiussed. In this way separation of the blades 30, 32 in a direction parallel to the pivot axis is resisted by each of the bolts 24 and 25. As before, the construction utilises a conventional coil spring 40 and a thumb catch 41.

It will be appreciated that an obvious modification of the constructions described is to arrangethat instead of the bolt 1'7 or the bolts 24, 25 overlapping the other handle or root of the blade attached thereto, the bolt or bolts could be interleaved with the other handle or root blade to achieve the same eifect. Another possible modification is that instead of providing the bolt 17 in the Figure 1 construction, or the bolts 24, 25 in the Figure 3 constructions, a, similar result can be. achieved by replacing the bolt head by a member forming an integral' part of the handle. Thus, this portion of the, bandle will have the form of an open-ended slot within which is fitted or interleaved the other handle, or the: root of the blade attached thereto. One surface of the portion of the blade root lying within the slot and/or the associated slot surface may be suitably inclined to give a cam action, so that even in the absence of any forces tending to separate the blades, the latter are brought closertogether or bear. gains on an her. with increasing pressure as the blades. are brought; together; in other words the. resistance to. lateral. separation. between. the blades increases as the. blades are. brought together.

Whilst the specific embodiments described. are adapted for use as hand pruning shears, it will be apparent. that the invention can readily be. applied to other tools. of the-kind specified, such as garden shears, scissors and'allpurpose shears.

What I claim is:

1. A tool comprising a firstcutting member, a first handle, said first cutting member being secured to. said first handle, a second cutting member, a second handle, said second cutting member being secured to saidsecond handle, -apivot, said first and second handle s be.- ing pivotally connected by said pivot, and a freelyrotatable member secured to said first handleand overlapping a part ofsaid second cutting member on the side of said second cutting member remote from said first cuttingmember.

2. A tool according to claim 1, wherein said first handle has a hole therein andsaid freely rotatable member comprises a bolt, said bolti extending, through said hole and having a head which overlaps said part of said second cutting member, a nut, and a toothed washer for locking said nut in adjusted position on said bolt, the separation between adjacent surfaces of said nut and said bolt head being greater than the combined thickness at the hole of said first handle and said part of said second cutting member.

3. A tool comprising a first cutting member, a first handle, said first cutting member having one end. overlying one end of said first handle and secured thereto, a second handle, a second cutting member, said second cutting member having, one end overlying said second handle and secured thereto, a pivot, said overlying ends of said first cutting member and said first handle having a hole therein, said overlying ends of said second cutting member and saidsecond handle having a hole therein, said pivot passing through said holes to pivotally connect said first cutting member and said first handle with said second cutting member and said second handle with said one end of said first cutting member in contact with said one end of said second cutting member, said first handle having a further hole therein, and a rotatable member positioned in said further hole, said rotatable. member having a part overlapping said one end of said second cutting member on the side thereof further from said one end of said first cutting member.

4. A tool according to claim 3, wherein said pivot comprises a bolt, said bolt having a head, a nut and means for locking said nut against rotation on said bolt, the separation between said nut and said bolt head being greater than the thickness of the portions therebctween of said first and second handles and said first and second cutting members; whereby said pivot is free to rotate.

5. A tool according to claim 3, wherein said pivot is ofisetto one-side of an imaginary line which bisects the angle between said first handle and said second handle.

6. A tool comprising a first cutting member, a first handle, said first cutting member having one end overlying one end of said first handle and secured thereto, a second handle, a second cutting member, said second cutting member having one end overlying said second handle and secured thereto, a pivot, said overlying ends of said. first: cutting member and said first handle having a hole therein, said overlying ends of said second cutting member. and said second handle having a hole therein, said. pivot passing through said holes to pivotally connect said first cutting member and said first handle with said second. cutting member and said second handle with said one end of said first cutting member in contact with said one end of said second cutting member, said'firsthandle having a further hole therein, a first rotatable member positioned in the further hole of said first handle, said first rotatable member having a partoverlapping said one end of said second cutting member on the; side thereof further-from said oneend of saidfirst cutting member, said second handle having a further hole therein, and a second rotatable member positioned in the further hole of said secondhandle, said second rotatable member having a part overlapping said one end of said first cutting member on the side thereof further from said one end of said second cutting member.

7. A tool according to claim 6, wherein said first rotatable member comprises a bolt, said bolt having a head which constitutes said part overlapping said one end of said second cutting member, a nut, and a toothed Washer for locking said nut in adjusted position on said bolt.

8.. A tool according to claim 6, wherein said: second rotatable member comprises a bolt, said bolt having a head which constitutes said part overlapping said one end of said first cutting member, a nut, and a toothed washer for locking said nut in adjusted position on said bolt.

References Cited in the file of this patent UNIT ED. ST ATES. PATENTS .m. Davina:

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