Patent GB-348506-A (GB)
Title: Improvements in flexible shaft couplings for the transmission of power
IPC: F16D3/56
Filed: 1929-11-09
Abstract: 348,506. Universal joints. STANDAGE, C. A. G., 15, Victoria Mansions, Queen's Club Gardens, West Kensington, London. Nov. 9, 1929, No. 34295. [Class 80 (ii).] In a resilient universal joint, for Cardan or other shafts, of the type wherein the shafts are provided with coupling members carrying a series of peripheral teeth between which are drive-transmitting blade springs, either solid or laminated, the springs are separate from one another, are supported in a housing, and are provided with transverse slots engaging flanges arranged in the housing to limit axial movement of the springs. A constant velocity ratio is obtained. As shown in Fig. 3, toothed members 26, 37 are coupled by springs 33 located by annular ribs 30, 24 engaging transverse slots in the springs. When solid springs are used these slots may have flared edges. Rib 24 is carried on a part 23 bolted to a housing part 27 7 and rib 30 is carried on a flange 29 bolted to a cap member 25 by bolts 32 which also secure the cap to the coupled member 26 by the use of a split ring 31 and a shoulder on the member 26. The main housing parts 25, 27 are held together only by the drive-springs through the locating ribs. An oil seal is formed by a spring-pressed spherical cover 40 in conjunction with a felt washer 42 on the outer spherical surface of the member 27. The cap 25 has an inner conical surface 36 which by depressing the ends of the springs during assembly facilitates sliding on of the cap. The springs which may be die-stamped from tempered high-tensile steel may as shown have a convex outer surface or both inner and outer surfaces may be so formed to increase their strength and flexibility. The tooth spaces may be tapered or flared away from the adjacent coupling surfaces, or the teeth may be of lozenge, circular, elliptical, or truncated conical form so that on angular movement the springs progressively contact with a larger tooth area and the stress on them is reduced. The teeth may be produced by drop-stamping and to increase their strength they may be completely shrouded being formed as slots flaring axially in all directions in one of the coupled members. In the forms shown in Figs. 3 and 14 a bearing ball 38 acts as a pivot for angular movement which may be of the order of 20‹. In Fig. 3 the ball and cups may be held together by spring means. One or both opposing surfaces 39 may be coned and the tooth spaces may be inclined as shown to permit this angular movement. In the form shown in Fig. 14, in which the ball and cups are positively held together, the outer surfaces 57<1> of the coupling members are spherical and the housing is supported on these surfaces by the provision of a guide ring 58<1> and packing strips 59<1> or by a ball race 66. The housing members are screwed together and there is a split or solid spacing ring 69 which has transverse notches engaging an extension 72 on one of the plates forming part of each laminated spring. Spherical sealing caps such as 40, Fig. 3, may additionally be provided, and the springs 68 are wholly concentric with the ball pivot. In a modification of this form the housing is rigidly supported on one of the members and the other member has a spherical portion engaging a guide ring on the housing as at 58<1>. Only one part of the springs is concentric with the ball 38. In a simpler form the ball and socket is dispensed with, and the housing is in two parts one part being rigidly mounted on one coupled member, the other part being mounted with clearance and the interposition of a packing ring on the other coupled member. In this form the slots and ribs are both arranged on the inner side of the springs and relative axial movement of the coupled members is permitted. In a further form the housing may consist of three parts, a central part and two end-caps all screwed together. The housing may also consist of two parts screwed together and having abutting flanges locked by set-screws. In some cases only one series of notches and ribs is provided. The coupling is shown at each end of a Cardan shaft the intermediate part of which is formed in two parts in splined telescopic engagement. The two parts are urged apart axially to maintain engagement of the balls and cups in each joint by an adjustable spring arranged either externally or internally of the hollow part of the shaft. The inner shaft part may be drilled to.facilitate transference of lubricant between the couplings and there is a stuffing-box between the hollow and solid parts of the shaft.