US2679906A - Horseshoe - Google Patents

Description

June 1, 1954 McGRAw ET AL 2,679,906

HORSESHOE Filed May 15, 1950 IN V EN TORS.

Patented June 1, 1954 "UNITED STATES PATENT OFFICE HORSESHOE Leo F. McGraw and Clarence McGraw, J oliet, 111. Application May 15, 1950, Serial No. 162,018

3 Claims.

This invention pertains to horse-shoes and, more particularly, to horse-shoes made by a forging process. The invention is especially useful in the manufacture of forged steel shoes for racing, trotting and riding horses but may be applied in making shoes for other horses and other animals commonly shod and to the manufacture of shoes made of other metals susceptible of being forged, it being understood that certain features of the invention may be applied to shoes formed by casting or other processes. A forged steel shoe for trotting and race horses will exemplify the invention and its several features.

Steel shoes for trotting and race horses are commonly forged from steel bars of rectangular cross-section. The steel may be 40.3 carbon steel or of other specifications. Preferably the bar is cut into lengths each of which s just sufficient after forging operations, to make a pair of shoes, one right and one left, when cut in the middle. Sometimes the shoesmith, blacksmith, or farrier prefers to obtain the shoes in the straight bar form and to cut, trim, shape and fit the shoes from the bar and sometimes he prefers the shoes already formed in the usual U-shape ready for the final steps of fitting and so forth. The invention is applicable in either event.

Many or most horse-shoes of the type mentioned have a relatively flat or slightly concave hoof-engaging surface at one side and on the other or ground-engaging side have a half-round surface portion along or over part of the shoe length, measured perimetrically, and a grooved surface portion extending along or over another part of the shoe length measured in the same manner.

Usually the half-round portion extends from the heel approximately to the toe portion along one side of the shoe while the grooved portion may extend across the toe and for a substantial distance along the opposite side of the shoe. The character, the position and the extent of the ground engaging portions and their relation to one another have various purposes and effects, for instance, the grooved portion may serve to provide traction and to give correctional effects to the footing of the animal and may serve other ends as well.

It has been found that one of the greatest, if not the greatest, points of weakness in shoes of the type mentioned, occurs at the juncture of the half-round portion and the grooved portion, breakage frequently happening at that place after use and even though the use may be very little. This weakness of prior shoes has been attributed in part to the methods and dies herev being forged or swedged tofore employed and in part to the physical characteristics of the joint or juncture between diiferent portions, produced by such dies and process as have heretofore been employed. Noticeable in many an ordinary shoe is the fact that the shoe section at the groove portion terminus with the half-round portion is flattened down or drawn in or otherwise distorted over such zone and thus weakened. In many cases also, the sharp angle of the groove or valley bottom tends to weaken the shoe at this juncture.

It is also a well known fact that prior forging or swedging processes have had the effect of unduly drawing out the bar in length and reducing it in cross-sectional area, during the forging or swedging that either a much lighter shoe than desired would be formed from a bar of given cross-sectional area or one would be obliged to employ a bar of much greater cross-sectional area and unit weight to obtain the final unit weight of shoe desired. Then too, since the forging or swedging increased the bar length it has been the usual practice to start with a bar undersize in length to avoid wastage. In other words, following prior practices, it would be necessary to start with a bar oversize in unit weight and cross-sectional area and undersize in length, in order to obtain a shoe or shoes of a given weight for a given size and purpose. But by reason of variations in swedging operations it has been practically impossible to provide a shoe of a given weight by such prior processing. Shoes might vary as much as several ounces for the same size or original bar lengths and cross-section.

The invention has for its primary object the provision of a shoe whether in a bar form or U-shape which will be strong and resistant to breakage at the zone or juncture between a grooved or ridge and valley portion and a contiguous portion such as a half-round portion, as well as elsewhere there-along and one which will have a predictable unit weight and cross-sew tional area closely approximating the unit weight and cross-sectional area of the bar stock employed for the manufacture of the shoe thereby to avoid employing stock oversize in cross-sectional area and unit weight and undersize in length for the same end.

Many other objects as well as the advantageous results and the uses of the invention will be or should become apparent after reading the following description and claims and after viewing the several views of the drawing wherein:

Fig. 1 is a perspective view of a steel bar after and ready to be cut in operation, to such an extent the middle and the two parts bent and otherwise worked into a pair of shoes, right and left;

Fig. 2 is a full scale view of a finished righ foot shoe looking at the bottom or ground-engaging surface thereof;

Fig. 3 is a view, greatly enlarged, of a fragment of the shoe shown in Fig. 2, the better to illustrate the zone of juncture between a halfround side portion of the shoe and the valley and ridge portion at the toe thereof;

Fig. 4 is a compound view illustrating by successive sections taken along section lines A-A', B-B, C-C and D-D in Fig. 2, the cross-sectional profile of the shoe over the said juncture or juncture zone;

Fig. 4(a) is a sectional view taken along section line E-E in Fig. 2 to show the profile longitudinally of the juncture or juncture zone;

Fig. 5 is a perspective view of a forging or swedging die having forging or swedging recesses so formed as to enable the improved process or method to be carried out effectively; and

Fig. 6 is a plan view of the bottom or groundengaging surface of a fragment of a shoe made after the teachings of the prior art and illustrating, with a degree of exaggeration for emphasis, certain of the undesirable characteristics produced by such prior art processing.

In making the shoe shown in Fig.2 it is preferable to start with a bar, of suitable steel or other metal, having a rectangular cross-section and of such length as may be required for a shoe or pair of shoes of given weight and size specifications. Preferably also, the bar is of a length to make a pair of shoes, one right and one left, as indicated in Fig. 1 wherein I designates the original rectangular bar section and B and 9 designate the right and left shoe halves of the bar after forming or swedging but before being formed into the final U-shape of the shoe. However, the shoes are separated from one another before being finally shaped by cutting the bar in half at the dotted cutting line designated [0. Each finished shoe may have a portion ll of rectangular cross-section, a portion l2 of W or M shape (depending upon the view) in cross-section and a portion l3 of half-round cross-section. The form or shape of portions H and I3 are not unusual, per se, except insofar as they may be affected by the new construction and processing so will not be described in all detail.

Fig. 6, with some exaggeration for emphasis and clarity illustrates, in part, what commonly happens when an ordinary shoe of the type chosen for this disclosure is manufactured by prior processes and with prior dies. Here, as will be observed, that portion designated M which lies at the juncture between a W or M shaped groove and ridge portion i2 and a half-round portion 23, is often thinned downbetween its top and bottom faces and depressed, drawn-in or necked-in at the sides, a resultant, it is theorized, of the type or construction of the die and the process heretofore utilized which effect a reduction in the width and cross-sectional area of the shoe over this juncture portion between the half-round and grooved portions. In the prior process the dies employed have been so constructed that the forging or swedging recess for the grooved portion of the shoe was continuous from end to end of the die block and embraced no part of the half-round recess which also was entirely separate and ran from end to end of the die block embracing no part of the Accordingly the grooved portion of a shoe bar such as that of Fig. 1 was completely formed in one operation in one die recess and the half-round portion was completely or partially formed in a second operation in a second die recess, the particular portion being worked on being pre-heated to the desired or proper forging temperature before the forging or swedging operation on such portion in its particular recess. In such dies and with such processing no part of either portion was formed or forged while the adjacent portion was being worked upon with the result that the metal at the juncture zone was weakened relative to the adjacent portions of the shoe.

Another factor apparently contributing to weakness and premature breakage of such shoes at or adjacent to the juncture zone is the relatively abrupt terminus of the groove or valley and ridges at the juncture with the half-round portion and the sharp and relatively deep valley at such juncture. This structural feature together with the drawing-in and reduction of the cross-sectional area of the metal of the shoe as above related, weakens the shoe at or over the juncture zone to such a substantial degree that breakage thereat with possible serious results to the horse may occur. While the foregoing statements are based partly on hypotheses to explain the reason for frequent breakage and the almost constant breakage of prior art shoes in the juncture zone, it has been found that by using the new type of die with the new process hereinafter more fully described a new shoe is produced which is not subject to breakage or to greater wear at or within or adjacent to the juncture zone than elsewhere.

The new process utilizes a die block such as that of Fig. 5 wherein the forging or swedging recesses or channels l5, l6 and H are formed. Recesses or channels l5 and I! are similar to one another as they vary only that one is right-hand and the other left-hand so far as the groove and ridge forming portions 15' and ll of those recesses are concerned. Each of'the portions 15 and I1 is of sufficient length to form the entire grooved or ridge and groove portion of theshoe while the half-round portion 15, ll", respectively, into which it merges, is of a length sufficient to extend a substantial distance beyond the zone of juncture of the two portions. For example, for a shoe having a length (measured around its perimeter, or one-half of the bar of Fig. 1) of 13 inches and a grooved length of approximately 5 /4 inches, it is desirable that the half-round recess portions 15" and'l'l" be from 1 inches to 2 /2 inches long although a satisfactory result may be obtained when the halfround portion of a die recess or channel is as little as /2 to inch in length and, onthe other hand, such portion may be over half as long as the total length of the half-round portions of two shoes when made in a single bar such as that of Fig. 1.

Each of the die recess portions 15' and H. has a W-shaped bottom providing parallel V-shaped valleys one of which is slightly (approximately /8 inch) deeper (measured from the top surface of the die block) than the other in the embodiment illustrated where the top width of the die recesses may be ,approximately'Vg inch and the maximum valley depth of the deepest valley is approximately /8 inch. The distancefromthe top surface of the die block to the crest of the ridge !8 of inverted V-shape between the valleys may be approximately g inch. Where the ridge I8 adjoins the half-round recess portion itiscut 5. away as indicated at I9 beginning at a point on the crest that lies distant from the terminus of the deepest valley by approximately 4 inch and distant from the terminus of the adjacent shallow valley by approximately inch, the shallow valley, at the end adjacent to the half-round recess, terminating approximately /8 inch short of the corresponding terminus of the deeper valley.

Each of these two valleys gradually becomes more shallow as it approaches its terminus or juncture with the half-round portion of the recess at which place the surfaces merge without an appreciable shoulder or step, as is preferable. Preferably also the surface at l9 in the die is concave in two directions, 1. e., in effect is approximately a segment of a spherical surface having a radius approximately equal to the radius of the surface of the half-round portion of the recess. Measured longitudinally of the die block recess the surface l9 extends from the half-round portion of the recess for a distance approximately equal to inch or somewhat more than /2) one-half of the width of the shoe, it being preferred that this measurement be at least equal to one-half of the shoe width for the purpose of maintaining substantially the same cross-sectional area of the shoe throughout the said juncture zone if not entirely throughout the length of shoe measured along the perimeter. At the opposite end of each of portions l5 and I1 the ridge I8 may be bevelled or rounded off, as indicated at 2! to avoid an abrupt or sharp corner but the stresses imposed on the ortions of a shoe formed in this part of the die are not of the importance or effect of those stresses applied at the aforesaid juncture zone.

Following the normal forging process steps of pre-heating and swedging the bar to provide the groove and ridge portions and the half-round portion therebetween but varying that process by forging a part of the half-round portion simultaneously with the forging of each of the groove and ridge portions using a die such as that described, a double shoe bar such as that of Fig. 1 is made. Preferably, a bar of rectangular crosssection is heated over such length as may be required to have that portion which is to be forged in recess I 5 at the necessary forging temperature whereupon it is positioned in the recess I 5 and drop-forged throughout the length of such recess. Thereafter the other heated and forged in recess [1, whereupon the center section is heated and forged in recess I 6. After trimming off any flashing which in most instances is extremely slight and after any straightening that may be necessary and cooling, the bar is ready for fashioning into a pair of shoes. The forging operation causes the metal to flow into the die recesses and fills them so that upon completion of the forging operation the exposed or upper face of the bar in the die recess is substantially flush with the top surface of the die.

A full scale shoe made with a novel die and after the novel method above described is illustrated in Fig. 2 with certain details emphasized in the views of Figs. 3, 4 and 4(a). Referring to these figures of the drawing it should be noted that the portion II is of rectangular cross-section and is of the original transverse dimensions which, in this instance are inch by 3 inch. After forging or swedging and the subsequent shaping or fashioning of one-half of the resultant bar, the groove and ridge portion l2 and the halfround portion have the appearance, in plan, of

end of the bar is similarly Fig. 2 from which it will be observed that the valley or groove 22 extends along one side and across the toe of the shoe bordered on the inside by the shallow ridge or rib 23 and on the outside by the high ridge or rib 24. That end of valley 22 which is adjacent to portion H is gradually widened and sloped up to the surface of portion II as indicated at 25 whereas the opposite end of the valley has an upwardly extending and widening slope 26 of convex contour resulting from the impression of the concave surface H) of the die recess in which it was formed.

While the groove and ridge portion has a hoof engaging face which may be made slightly wider (approximately inch to 1% inch) than the width of the corresponding face 20' of the half-round portion, in which case the side walls will have a slight converging taper from the groove and ridge portion to the half-round portion along the immediate junction zone, the width of both face portions may be made the same. Nevertheless the cross-sectional area of the shoe at subtantially any point from one heel end to the other will be substantially uniform and this 7 is particularly important over the shoe length (measured on the perimeter) throughout the juncture zone which may be considered as beginning say, one inch to each side of the section line CC. The effects of holding the cross-sectional area substantially uniform throughout the shoe length will be apparent from the following comparative results of employing the old process and old die and employing the new process and the new die, in each case swedging a rectangular bar to provide a pair of shoes of identical size,

i. e., 13 inches long around the U from heel point to heel point. Old process and old die: Initial dimensions of bar, %"X1"X22" in length; length after working, 27". New process and new die: Initial dimensions of bar, x x 25 in length; length after working, 26

From the above example it will be appreciated that there is a substantial saving of metal through this invention and that the shoe made by the old process and with the old die is stretched out,

' thinned down and weakened by the processing.

Therefore, too, the old shoe has substantially less weight for its size than the new shoe and it is difficult if not impossible to obtain the correct weight for a given shoe size in the old process unless allowance is made in the die recess size and an initially oversize bar section is employed. It may be mentioned here that the apparently excess length of 1 6 inch of the new process bar of the above example, after working, is approximately what would be lost in sawing or otherwise cutting the bar in two. Weight determinations for particular sizes are easily figured when using the new die and process.

While we have illustrated and described our invention in its preferred form and have disclosed it in its application to one type of horse-shoe, we desire to be limited only by the spirit of the invention and the scope of the appended claims.

We claim:

1. A forged-metal horse-shoe having a hoofengaging face, the surface of the opposite face including a first portion that is convexly curved in a direction transverse to the shoe perimeter along such portion, and a contiguous second portion having a pair of outwardly projecting ridges with a V-shaped valley therebetween, said convexly curved surface portion having a terminal part convexly curved transversely and longitudinally and extended into said valley between said ridges, said terminal part gradually descending into said valley between said ridges and terminating in the valley root, said ridges gradually decreasing in height at their ends adjacent to said terminal part of said convexly curved portion and merging with said convexly curved surface portion, the said terminal part and the adjacent ridges being coextensive for a distance approximately equal to at least half of the width of the shoe measured transversely of the perimeter substantially at said terminal .part location, the cross-sectional area of the shoe being substantially uniform throughout the first and sec end portions.

2. As an article of manufacture, a relatively straight metal bar comprising a pair of horseshoes in an intermediate stage of formation, a portion of the bar adjacent to each end having a V-shaped valley extending longitudinally of one surface between the side edges thereof and an inverted v-shaped ridge at each side of the valley and substantially coextensive therewith, each pair of said ridges and the valley therebetween being so situated as to extend along at least a portion of the toe of the ultimate shoe, the corresponding surface of that portion of the bar which is intermediate of the valley and ridge portions of the bar being convexly curved transversely of the barlength, said intermediate portion terminating at each of its ends in a part extending and declining with convex curvature downwardly into the adjacent valley between the adjacent ridges, the cross-sectional area of the bar throughout that length over which a terminal part of the intermediate portion is coextensive with the adjacent ridges being substantially uniform.

3. As an article of manufacture, a forged metal horse-shoe having a hoot engaging face and an oppositely disposed ground engaging face, the ground engaging face having a portion of its perimetrical length formed with a V-shaped valley extending perimetrically ofsuch portion between the side edges of the shoe and having an inverted V-shaped ridge extending along each side of said valley and substantially co-extensive therewith, said ridges and. the valley therebetween being so situated as to extend alongat least a portion of the toe and a portion of one side of the shoe, another perimetrical length portion of the shoe that is adjacent to the first said portion having its corresponding surface convexly curved transversely of the shoe perimeter, said second lengthportion terminating at one end in a transversely and longitudinally convex part extending, gradually downward into said valley between the adjacent ends of said ridge, the shoe throughout that perimetrical length over which the said convex terminal part of the second said portion and the adjacent ridge are co-extensive being substantially uniform in cross-sectional area.

References Cited in the file of this patent UNITED STATES PATENTS V Number Name Date 57,030 Wilkinson Aug. 7, 1866 163,555 Walker May 18, 1875 182,731 Williams Sept. 26, 1876 223,111 Bryden Dec. 30, 1879 0 228,974 Billings June 22,1880

* 265,908 Wilcox Oct. 10, 1882 320,350 Greenwood June 16, 1885 330,534 \Nhite Nov. 1'7, 1885 421,349 Bryden Feb. 11, 1890 m 446,735 Eynon et al Feb. 17, 1891 541,956 Benfield July 2, 1895 845,211 Yost Feb. 26, 1907 OTHER REFERENCES Metals Handbook, 1948 ed.; pub. by Amer. So- 4 ciety for Metals, Cleveland, Ohio; pp. 123, 244,

245. Copy in Div. 14.

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