Patent GB-1170104-A (GB)
Title: A Multipart Casing for an Electrical Machine.
Inventor: FELDHOFF HEINRICH
IPC: H02K5/04
Filed: 1967-02-02
Abstract: 1,170,104. Dynamo-electric machine casings; machines with permanent magnets. BADISCHE ANILIN- & SODA-FABRIK A.G. 2 Feb., 1967 [3 Feb., 1966], No. 5102/67. Heading H2A. In a casing, comprising at least two members, for an electrical machine, in which two mating coaxial members are adapted to be secured together by a single or multi-part locking ring, each of the members is provided with a grooved skirt whose outer circumference is less than that of the adjacent part of the member; the skirt is either continuous, in which case the two mating members taken together provide two axially-separated grooves for engagement by an appropriately-shaped locking ring, or the skirt is interrupted to form projections which fit between the projections of the mating member, in which case only one groove, in effect, is provided, for engagement by a differentlyshaped locking ring. As shown in Fig. 13, the invention is applied to an axial air-gap motor having two disc armatures 3 and four annuli of permanent magnet stator poles 3a; the casing comprises two end members 1, 2, and an intermediate member 23. (In Fig. 1, not shown, the motor has only one disc armature, two annuli of stator poles, and a casing comprising two end members only). Fig. 2 shows an end view of a member 1 where the skirt is continuous: the outermost circumference shown is that of the skirt itself. Regularlyspaced arcuate portions of the land 6 between the groove 4 and the meeting face are removed at 7, so that a U-section locking ring 5, Fig. 4a, having internal gaps 10, may be slid axially on to the skirt into contact with the far side (not shown) of the groove 4. (The scale of Fig. 4a is slightly less than that of Fig. 2.) Then the skirt of a mating member may be inserted into the other face of the locking ring 5, with its recesses 7 aligned with the recesses of the member 1, until it makes contact with member 1. Finally, locking ring 5 is rotated to lock the members together and to retain the ring in position. Tapered surfaces may be provided to produce a wedge action on rotation. A moisture- or dust-proof joint may be formed by grooving the meeting faces of the members and incorporating an 0-ring seal in the space provided. The casing may be rendered explosion-proof by an additional ring such as is shown at 12 in Fig. 11, and in this case the locking ring 5 is secured at intervals around its circumference by screws (Fig. 6, not shown), releasable only by a special tool. Relative rotation of the mating members may be prevented by one or more axiallydirected locating pins or dowels (Fig. 5, not shown). As shown in Figs. 8 and 11, the skirt is interrupted to form projections 15 which are accommodated in the gaps 16 between corresponding projections on the mating member so that groove portions 17 form effectively a single groove into which may be inserted a split locking ring 19, Fig. 9. A continuous peripheral land 18 is left near the edge of maximum diameter of each mating member to assist exclusion of dust. The locking ring 19 may be secured in place by means of a pin located in an axial bore in one member and urged into a hole in the ring by a spring disposed in the bore behind the pin (Figs. 12a, 12b, not shown). Each locking ring may consist of a number of parts.