US2715262A - Method of forming sprags for one-way clutches - Google Patents

Description

Aug. 16, 1955 T. SZADY METHOD OF FORMING SPRAGS FOR ONE-WAY CLUTCHES Filed Feb. 5, 1951 F|G.2. A FlG.l.

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M E/L E l I INVENTOR.

LEOPOLD T.SZADY BY m W ATTORNEYS United States Patent METHOD OF FEBRMING SPRAGS FQR ONE-WAY CLUTCHES Leopold T. Szady, Detroit, Mich assignor to Formsprng Company, Van Dyke, Mich a corporation of Michigan Application February 5, 1951, Serial No. 209,356

3 Claims. (Ci. 29-414) The invention relates to the method of making oneway clutches including coaxial driving and driven rotary members having radially spaced concentric raceways thereon, and a series of sprags interposed between said raceways. With such constructions it is necessary to provide means for energizing the sprags or turning them so as to frictionally engage the raceways. This is som times accomplished by garter springs surrounding the series of sprags and engaging properly inclined notches or apertures therein, so as to impart to each sprag a torque stress. With certain constructions garter spring receiving notches are formed in one or both ends of the sprag usually subsequent to the severing of the sprags from a stock bar and the heat treatment for hardening the same. However, this requires not only a distinct mechanical operation but also the orienting of the separate sprags for feeding to the notch forming means.

It is the object of the instant invention to obtain a construction of sprag in which the spring receiving notches may be made in the stock bar prior to the severing of the sprags therefrom.

To this end the invention consists in the constructio of the sprag and the method of forming the same as here inafter set forth.

In the drawings:

Fig. 1 is a side elevation of a sprag of my improved construction;

Fig. 2 is an end elevation thereof;

Fig. 3 is a plan view illustrating a method of forming the notches in the stock bar and then severing the bar into individual sprags;

Fig. 4 is a view similar to Fig. 3 illustrating a me ified method for forming the notches in the stock bear and for severing the same into individual sprags;

Fig. 5 is a side elevation of the construction of sprag illustrated in Fig. 4; and

Fig. 6 is an end elevation thereof.

My improved sprag may be varied as to its cross sectional contour but, as specifically illustrated, this contour includes diametrically opposite eccentric cam p0r tions A and B, a generally radial side C between said cam portions and an opposite side having oppositely i"- clined portions D and E extending to a central rounded nose portion F. The sprags may be formed from drawn or extruded stock bars having the cross sectional contour as just described and such bars are severed into suitable lengths for forming the individual sprags. However, before the severance of the sprags the bar is notched and the notches are located to be at one or both ends of the severed sprags. The notches G extend transversely across the sprag adjacent to one of the cam surfaces thereof and are inclined from the side C to the side portion E. Thus with a series of sprags in assembled relation to the other elements of the clutch, a garter spring can be engaged with the notch of the sprag and will bear thereagainst at one side of the center of turning of the sprag so as to impart a torque stress thereto. This will energize the sprags to turn the cam faces A and B thereof into fric- 2,715,262 Federated Aug. 16, 1955 tional engagement with the raceways on the driving and driven members. To retain the garter spring when once engaged, the notches G are undercut as indicated at H so that the resilient pressure of the spring against such undercut portion will hold it from endwise displacement.

In the method of forming the sprags, as above described. the stock bar I is advanced longitudinally step by step a distance equal to the length of the sprag plus the material removed in the severing of the bar. The notches G with their undercut portions H are formed by moving a suitable fashioned rotary cutter I transversely across the bar and through a path to give the proper inclination to the notch. The cross section of the cutter J corresponds in contour to the undercut portion H of the notch. The bar is severed into sprag lengths by a rotary cutter K and if desired this may be coaxial with the cutter I but projects beyond the periphery of the latter to extend completely across the bar. It will, of course, be understood that Where both operations are performed simultaneously by cutters J and K on the same arbor it will be necessary to hold the bar from transverse displacement during this operation.

Sprags formed by the method above described only require heat treatment and hardening to complete the same and are then in condition for assembly in the clutch.

With the modified method illustrated in Fig. 4, a rotary cutter or grinder Wheel L is fashioned to form the notches in the bar and this same cutter is used for severing the bar into individual sprags. In alternate operations of the cutter L, it is moved iaterally different distances With respect to the bar M and intermediate each operation said bar is advanced an amount substantially equal to onehalf the sprag length. Thus in one operation of the cutter L, it is moved to form a notch in the sprag and in the alternate operation it is moved completely across the bar to sever the sprag therefrom. As the advancement of the bar is between each operation of the cutter, the notch will be located centrally between the ends of the severed sprag.

What I claim as my invention is:

l. The method of forming sprags for one-Way clutches comprising forming a stock bar having a cross sectional contour including diametrically opposite eccentric cam portions, cutting successive spaced transverse channels through one of said cam portions while integral with said stock bar and severing the bar into sprag lengths, each including at least one of said channels.

2. The method as in claim 1 in which spaced pairs of adjacent channels are cut through said cam face the channels of each pair being fashioned to increase in depth in directions away from each other, and severing the bar between adjacent channels of each pair to form in the severed sprags undercut channels opening through opposite ends thereof.

3. The method as in claim 1 in which the forming of the channels and the severing of the sprags is performed by the same cutter in alternate operations thereof the severing operation being of greater depth.

References Cited in the file of this patent UNITED STATES PATENTS 2,100,619 Wenn Nov. 30, 1937 2,156,692 Hixon May 2, 1939 2,165,454 Cornell, Jr. July 11, 1939 2,213,040 Drissner Aug. 27, 1940 2,282,537 Whitney May 12, 1942 2,459,568 Lyon Ian. 18, 1949 2,486,603 King, Jr. Nov. 1, 1949 2,542,914 Farkas et a1 Feb. 20, 1951 2,557,773 Steinman u June 19, 1951

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