US2604695A - Shear - Google Patents

Description

y 1952 F. L. MOGARY ETAL SHEAR 2 SHEETS-SHEET 1 Original Filed Oct. 3, 1944 fialzcial. JZOG 9 Lkarleu EQ ZQGaI y 1952 F. L. MOGARY ETAL SHEAR 2 SHEETS-SHEET 2 Original Filed Oct. 3, 1944 Patented July 29, 1952 SHEAR Francis L. McGary and Charles E. McGary, Hardinsburg, Ky.

Original application October 3, 1944, Serial No. 556,968, now Patent No. 2,449,561, dated September 21, 1948. Divided and this application June 22, 1948, Serial No. 34,386

Our invention relates to a shear for sheet metal and the like, and it is an object of the sam to provide a shear that shall have a simple, direct and powerful action.

Another object is to provide an improved movable shear blade. p

Still another object is to provide improved means for guiding the severed edges of the Work past the shear, in both a bench type shear and in a hand-held shear, whereby to guide such edges in a way to permit ready and free turning of the shear or the Work to either side as in cutting various shapes other than straightsided figures, without interference of the cut edges with the shear blades or the other parts of the shear, or the hands of the user;

Referring now to the drawings, which are annexed hereto and made a part of this application, and in which similar reference characters indicate similar parts;

Fig. 1 is a. side elevation of the shear,

Fig. 2, a plan view of the same,

Fig. 3, a bottom plan of the same,

Fig. 4 an elevation showing the side opposite to that shown in Fig. 1,

Fig. 5 an elevation similar to Fig. 4 but with the shear open, and

Fig. 6, a front end elevation.

In the drawings reference characters 35 and 36 indicate handles such as may be similar to those shown in our U. S. application Ser. No. 556,967, which issued on June 1, 1948 as Patent #2,442,424. These handles are connected by any suitable means, here shown as consisting of parallel links 31 and 38 pivoted to the handle 35 at 39 and to the handle 36 at 40. The clos ing movement of the shear is limited by a lug 1 Claim. (01. *.244)

.2 ing the shear forward or pulling it backward, all without crowding the other fingers.

The handgrip portion 45 of the upper handle has its lower part marked a in Fig. 1, offset from the plane of movement of the handles quite sharply, and this partis recurved at its rear end so as to lie approximately in said plane or a little to the left thereof (looking in the direction of movement of the shear) and the upper part, marked 12 in Fig. 1, starts from said plane, is then slightly offset toward the right of the shear, and is then recurved so that its rear end, with the rear end portion of the grip, lies well to the left of said plane, the parts a and b being separated about 50% more widely than corresponding parts of the grip portion 42 so as to accommodate the rear joint of the thumb and afford maximum opportunity to exert force in closing the shear.

A shear blade 46 is shown as being formed integrally with the lower handle 42. This blade, as best shown in Figs. 5 and 6, is relatively thick at its rear end and becomes gradually thinner toward its front end, i. e., toward the front or cutting end of the shear. Its upper face which may be called the shearing face is inclined upwardly from its outer edge toward the cutting edge and its under face which may be called on the handle 35, positioned to strike the adjacent portion of the handle 36.

The handgrip portions of the handles are formed for convenient engagement by a hand of the user in such manner that he may apply force most effectively and with a minimum of fatigue. For this purpose the lower handgrip portion 42, in the position of use of the shear, is offset laterally with respect to the plane of movement of the handles and is slightly recurved, this part being shaped to receive all of th users fingers except the index finger. The latter is provided for by a finger hole at 43, and it will be noted that the wall at 44 is relatively wide on account of the offsetting of the remaining handgrip portion, thus aiding in the provision of a wide part against which the index finger may bear effectively and without discomfort in pushthat is sharply inclined upward from the outer edge toward the cutting edge in about the midlength of the blade, but toward the rear end is gradually tilted downward so as to leave the blade of substantial thickness toward the rear end, as shown in Fig. 5. This under face is only slightly convex at its forward end, it lying nearly in an oblique plane to cause the one cut edge of the work to be slid freely underneath said face, and its inclination and convexity increasing toward the rear end of the blade as shown in Fig. 6, to provide greater strength toward the rear end of the blade. Both this blade and the cooperating blade 4'! at the front end of the shear (Fig. 6) lie substantially in a plane inclined to the horizontal at a low angle, approximately 15.

The shear blade 41 is pivotally connected to the blade 46 by means of a stud 48 fixed to the forward part of the handle 36, and is held in place by a nut 49 threaded on the stud, a washer 50 being interposed between the nut and the adjacent face of the blade 41. Said blade 41 has a rearwardly projecting arm pivoted to the handle 35 by means of a bolt 5|, here shown as being of the type having a notched head for a. screw steady and brac the blade in operation. The

blade is heavy at its rear and adjacent the pivot and at its outer side, as above stated, but tapers forwardly and laterally so that its cutting edge is relatively thin in a vertical direction, as shown in Fig. 11. Thus the upper or casting-01f face of blade 41 is only slightly convex at its forward end and lies nearly in an oblique plane to cause the other out edge of the work to slide freely over it, the inclination and convexity increasing toward the pivot to provide the necessary strength in the blade. The cutting edge of blade 46 and its lower or cutting face are curved upward from both ends toward the middle while the cutting edge of the blade 41 is curved downward from both ends toward the middle of the blade, or oppositely to the coacting edge, as shown in Fig. 10. By reason of the conformation of these edges the blades tend to maintain a distance from the workexcept at the point of impact and close thereto. Because of this and also because of the shape of the blades and the fact that they lie in planes inclined to the plane of movement of the handles and to the horizontal (or to a plane at right angles to the plane of movement of the handles), it becomes possible to turn the shear from its direct straight line of out either to the right or to the left and to any desired extent, so as to cut shapes of many varieties such as could be out only with great difficulty heretofore, if at all, due to the fact that the work was in the way of the shear blade, and especially so in attempting to turn the shear to cause the cut to veer to the left.

It will be understood that the shear is here shown as made for the use of a right-handed user, and that for left-handed persons the necessary alterations to fit it for such use will be made therein.

It will be obvious to those skilled in the art that numerous changes may be made in the devices herein disclosed, all without departing from the spirit of the invention; and therefore we do not limit ourselves to what is shown in the drawings and described in the specification, but only as indicated in the appended claim.

Having thus fully described our invention, what we claim is:

A shear having a rigid handle carrying a lower blade, an upper blade pivoted to said lower blade, a second handle pivotally associated with the rigid handle for operating said upper blade, said blades having shear edges divergently curved from a point near said pivot to their free ends, the lower blade having a substantially flat upper work supporting face inclined downward from its shear edge toward its outer margin and a casting-01f under face slightly convex transversely of the blade, said face being inclined downward laterally toward the shear edge and from the free end of the blade toward the other end to provide an extensive thin area at the free end of the blade and along its shear edge; the other one of said blades having an oblique under face approximately in the same plane as the casting-ofl face of the coacting blade when the shear is closed and an upper casting-01f face slightly convexed transversely of the blade, said blade being curved downward laterally of the blade toward the cutting edge and downward toward the free end of the same to provide an extensive thin area on said blade lying approximately in the same plane as the coacting portion of the coacting blade when the shear is closed.

FRANCIS L. MCGARY. CHARLES E. McGARY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date D. 101,791 Rauh Nov. 3, 1936 1,092 Heinisch Feb. 27, 1839 579,085 Wesselmann Mar. 16, 1897 639,874 Thuiller Dec. 26, 1899 968,219 Wheeler Aug. 23, 1910 1,779,889 Purcell Oct. 28, 1930 1,987,375 Simonsen et al. Jan. 8, 1935 2,264,840 Isacc Dec. 2, 1941 2,292,271 Heise Aug. 4, 1942 FOREIGN PATENTS Number Country Date 122,552 Great Britain Jan. 30, 1919 749,064 France May 3, 1933

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