FR2586601A1 - METHOD FOR MANUFACTURING A THREE-PINION FREE WHEEL BODY, AND FREE WHEELS OBTAINED - Google Patents

Abstract

A.PROCESS FOR THE MANUFACTURING OF A FREEWHEEL BODY WITH THREE SPROCKETS. B.PROCEDE CHARACTERIZED IN THAT WE MAKE THE PINION OF INTERMEDIATE DIAMETER1 BY FORMING A CIRCULAR EDGE5 ON EACH SIDE OF ITS CENTRAL OPENING; SHOULDERS9, 10 WITH A DIAMETER LESS THAN THE DIAMETER OF THE EDGES, SHOULD BE SHAPED ON THE FREE END OF THE OUTER SIDE OF THESE EDGES; WE MAKE SEPARATELY THE SMALL AND LARGE SPROCKET 2, 3 OF THE FREE WHEEL, THESE SPROCKETS SHOWING A CENTRAL OPENING11, 12 WHOSE DIAMETER CORRESPONDS TO THAT OF THE SHOULDERS OF THE INTERMEDIATE SPROCKET1 AND THE EDGES AND OF THE BIG OPENINGS ARE FIXED BY WELDING SPROCKET ON THE SHOULDERS OF THE INTERMEDIATE SPROCKET.

Description

2586-6 01

  The invention relates to a method for producing a three-pinion freewheel body, and

than the free wheels obtained.

  For reasons of economy of investment

  and speed of realization of wheel bodies

  At present, there is a tendency to replace

  former welding processes that required either a one-piece machining of the pinion body, or a machining of several independent parts involved in the constitution of the freewheel. However, the welding manufacturing processes of the free wheel bodies developed so far can not be regarded as perfect insofar as it is desired, on the one hand, to further reduce the cost price and, d On the other hand, improve the quality of the finished product regarding the strength of the body

  of freewheeling, the precision of parallelism and

gables, etc.

  The present invention relates, for this purpose, to a method for manufacturing a three-pinion freewheel body, characterized in that the intermediate diameter pinion is produced by forming a circular rim on each side of its central opening, form, on the free end of the outer face of its flanges, shoulders of diameter less than the diameter of the flanges, is made separately small and large pinion of the freewheel, these two gears having a central opening whose diameter corresponds to that of the shoulders of the intermediate gear and is fixed by welding the edges of the central openings of the small and large pinion on the shoulders of the intermediate gear. According to another characteristic of

  the invention the circular shoulders of the flanges comprise

  a conical bearing extended by a cylindrical bearing

than.

  According to another characteristic of the in-

  the small and large gables present openings

  central tears with a slightly larger diameter

  to the diameter of the cylindrical bearings.

  According to another characteristic of the in-

  vention the intermediate gear with its flanges and its circular shoulders is obtained by cold discharge. According to the X--; the invention the small pinion -; - Y n n - p 'sente

  a crenellated circular central opening.

  The invention is shown by way of non-limiting example in the accompanying drawings in which: - Figure 1 shows in half section the three component parts of the freewheel according to the invention, Figure 2 is a view left partial of the intermediate gear of FIG. 1; FIG. 3 is a partial view of

left of Figure 1.

  The freewheel shown in FIG. 1 comprises three pinions, namely a pinion of intermediate diameter 1 placed between a pinion of smaller diameter 2 and a pinion of larger diameter 3.

  gears being provided at their periphery with a toothing 4.

  According to the invention, the intermediate gear 1 is obtained by cold-pressing a metal disk so as to form a shoulder 5 of

  each side of the metal disk. These shoulder-

  5, obtained by displacement, define the central opening 6 in which are preformed the circular raceways 7 for the balls of the freewheel, and a circular central rib in which must

  be cut the teeth of ratchet 8 of this free wheel.

  Shoulders 5 which are generally shaped

  the cylindrical section with a circular section, at their ends

  mites free, a conical bearing 9 extended by a cylindrical bearing surface 10, whose diameter is smaller than that of the

  outside diameter of extensions 5.

  This intermediate gear being thus preformed it then undergoes a cutting operation with the purpose

to form the teeth 4 of this pinion.

  Spans 9 and 10 are intended for

  receive the gears 2 and 3 which are made separately.

  These pinions 2 and 3 are obtained by a cutting operation of flat metal discs, this

  operation which has the effect of directly forming the

  the central openings 11 and 12 of the pinions and their teeth 4. The central openings 11 and 12 of these pinions are of a diameter slightly greater than the diameter of the cylindrical seats 10 so that they can fit, the cylindrical bearing surfaces 10 serving then to center the two pinions 2 and 3 which abut by the angles Il and 121 of their openings against the conical bearing surfaces 9.

  When pinions 2 and 3 are thus posi-

  conical and circular bearings 9 and 10 the assembly then undergoes an electric welding operation whose characteristics are determined so that the

  angles 111, 121 interpenetrate with the contiguous

  9 so that the planes of gables 2 and 3 are

  parallel and equidistant from the plane of the intermediate gear 1.

  When these circular welds of the two pinions 2 and 3 on the pinion 4 are produced, the assembly then undergoes the machining operation of the two raceways 7, as well as the cutting operation of the ratchet teeth 8, then subjecting the resulting freewheel body to a cementation treatment with the purpose of

to harden the metal.

  In the embodiment of FIG. 1, the circular central apertures 11 and 12 of the pinions 2 and 3 have a smooth periphery and the angles 111 and 121 apply in a continuous manner to the conical bearing surfaces 9 so as to obtain continuous welding. If desired, however, this assembly can be made by welding in a discontinuous manner and in this case the periphery of the circular central opening.

will be provided with slots.

  Thus, according to FIG. 3, there is shown an embodiment of pinion 3 by which the initial metal disk undergoes a cutting operation having the effect of forming at the same time toothing 4, the circular central opening 12 whose periphery comprises slots 122 and a circular line of perforations 13 for lightening this large pinion and therefore the body

Freewheeling.

  The number of these regularly distributed slots and their spacing will be determined by

  depending on the welding conditions to obtain an assem-

  Robust and precise positioning of this pinion

  relative to the intermediate gear 1.

R E V E N D I A T IONS

  1) Process for manufacturing a three-pinion freewheel body, characterized in that the intermediate diameter pinion (1) is formed by forming a circular rim (5) on each side of its central opening, forming, on the free end of the outer face of these flanges, shoulders (9, 10) of diameter smaller than the diameter of the flanges, the small and large pinion (2, 3) of the freewheel are produced separately, these sprockets having a central opening (11, 12) whose diameter corresponds to that of the shoulders of the intermediate gear (1) and is fixed by welding the edges of the central openings of the small and

  the large pinion on the shoulders of the intermediate gear.

  2) Method according to claim 1, characterized in that the circular shoulders of the flanges comprise a conical seat (9) extended by

a cylindrical bearing (10).

  3) Process according to any one

  of the preceding claims, characterized in that the

  small and large pinions (2, 3) have central openings (11, 12) with a slightly larger diameter

  to the diameter of the cylindrical bearing surfaces (10).

  4) Process according to any one

  of the preceding claims, characterized in that

  the intermediate gear (1) with these flanges ($ 5 and these circular shoulders (9, 10i) is obtained ;. by cold discharge.) Process according to claim 1, characterized in that the small gear (2) and / or the large gear pinion (3) has a circular central opening

(12) crenellated.