GB1162122A - A Direct-Current Motor - Google Patents

Abstract

1,162,122. Mounting rotors for dynamoelectric machines; core constructions. SIEMENS A.G. 1 Dec., 1966 [1 Dec., 1965], No. 53950/66. Heading H2A. A direct-current motor incorporates a permanent magnet system mounted on the motor shaft, a fixed armature winding mounted on a former consisting of two shell-like parts having means for fixing the two parts together, the motor shaft being mounted in bearings associated with the former, and a magnetic return path surrounding the former. Preferably, the former is drum-shaped and consists of two identical parts 5, one of which is shown in Fig. 2. Preferably, the complete former has four fins 12, two of these being formed by the juxtaposition of fin portions of less thickness lying in the plane of contact. Each part 5 has a boss-like extension 7 cupped at its inner end for reception of a bearing 4 (see Fig. 1). The bearing is then held in place by fitting of a spring 8, Fig. 1, gripped behind a projection 9 formed integrally with part 5. Next, the rotor with permanent magnet 3 is assembled with the parts 5 by pushing its shaft 1 into the bearings, after which the two parts 5 are joined together, using dovetail extensions and slots 17. Then the component windings 13, 14 of one phase are applied to the former by bi-filar coiling, and then the component windings 15, 16 of the other phase are applied at right angles thereto. The magnetic return path 23 consists of annular laminations which are pushed on to a mandrel (to define subsequently a smooth interior), the assembly being then located in a casing 22, and the casing being deformed at 24 to secure the discs together; the mandrel is then removed. Some of the annular laminations at one end of path 23 have openings forming two recesses 30 spaced 90 degrees apart, in each of which is later disposed a Hall generator 31 (one for each half of the stator winding). Each Hall generator is secured to a baffle plate 32, itself secured to a disc support 21, and a closure disc 27 is applied. Then the stator-rotor assembly is introduced into the casing, and lugs 18 on fins 12 are engaged in apertures 19 in support 21. Finally, disc 20, also having apertures 19 for engagement with lugs 18, is pushed on. Oil-impregnated discs 10 are provided for the bearings. Connecting tags 26 emerge from discs 21, 27.