GB868934A - Vibratory electromagnetic motor - Google Patents

Abstract

868,934. Hair clippers. WAHL CLIPPER CORPORATION. July 1, 1957, No. 20649/57. Class 131. [Also in Group XXXV] A vibratory motor comprises in the embodiment shown in Fig. 5 an electromagnet 30, 31 constructed to be energized by a fixed frequency alternating current and disposed in effective relation with a resilient vibratory armature 32 driving a resilient undertuned work arm 37 which is rigidly connected at one end to the armature 32, has an end and/or an intermediate portion extending alongside and spaced from the armature, and is positively connected to and drives a work element 42. Applied to a dry shaver or hair clipper the element 42 forms the cutter blade, and the armature and work arm are constructed to have natural tune frequencies which when there is no load on the blade are substantially different from the nearest multiple of the current frequency but which change toward resonance with the multiple when load is encountered whereby the armature vibration amplitude is increased. The armature and work arm vibrate in mutual opposition and have masses which mutually counterbalance thereby eliminating external vibrations. Embodied in a hair clipper Fig. 12 similar to that disclosed in Specification 793,742 which is referred to, the armature 60 has a resilient arm 61, 62 to which is fixed one end 66 of the work arm 65 which carries a bracket 69 whose finger 70 engages the movable blade 71. In another embodiment Fig. 13 the armature 43 is pivoted on a shaft 43a, oscillates relatively to pole faces 44, 44a but does not engage them, and is connected to the resilient work arm 44b carrying the work element 44d.