GB344451A - Improvements relating to electrically operated wind screen wipers for motor vehicles - Google Patents

Abstract

344,451. Windscreen wipers. LUCAS, Ltd., J. and MASON, S. A., Gt. King Street, Birmingham. Dec. 6, 1929, No. 37452. [Class 138 (i).] In an electrically-operated windscreen wiper, the body part in which the polepieces are embedded is of non-magnetic material and accommodates the worm gearing, and, in addition, it is so arranged that the bore for the worm bearing, the tunnel which encloses the armature, and a register at one end which locates a separate end cover, can be machined in a single operation or in a single setting of the body part in its jig. Preferably only one of the two polepieces is extended to receive a single field winding and the magnetic circuit is completed by a separate member which is slipped over the outer ends of the polepieces after the winding has been placed in position. In the form shown, the polepieces k, l are embedded in the non- magnetic cast body part j which accommodates the armature a, worm gearing d, e, and the crank mechanism. The register o at the end of the body part positions the end cover p which is preferably of insulating material. This register, the worm bearing and the tunnel for the armature can be machined in one operation. The U-shaped yoke n completes the magnetic circuit and encloses the field winding m. The wiper arm i on the shaft h is normally driven from the crank pin x through the toothed rod f, pinion g and a dog clutch (not shown) but it can be hand operated if desired after the shaft h has been moved axially to disengage the dog clutch.