Patent GB-741525-A (GB)
Title: Means for electrotherapy
Inventor: BROWNER WILLIAM JACK
IPC: A61N1/36
Filed: 1953-10-05
Abstract: 741,525. Electromedical apparatus. RELAXACIZOR, Inc.Oct. 5, 1953, No. 27226/53. Class 81(2). A device for the electrical contraction of muscles comprises a transformer having a plurality of cores arranged so that one portion of each core will lie adjacent a portion of each remaining core, coil means on the adjacent portions of the cores, means for passing oscillating current through the coil means separate secondary circuits having windings on separate portions of the cores and separate current strength control means connected to each of said secondary circuits. The device comprises a power input unit 1, a control circuit 2, oscillator units 3, 4 and ouput circuits 5, 6. The power unit includes an autotransformer 9 having a primary winding 14 and secondary windings 13, 15. An electric motor 22 rotating at 20 rotations per minute is connected across power lines 7, 8 and is provided with a shaft 22a carrying a cam 25 which contacts a spring contact 24 in switch means s in the control circuit 2, the spring contact 25 being connected with the autotransformer 9. The cam 25 comprises sections a, b, c and d. When a first section a contacts the spring contact 24, the latter contacts a contact 27 of the switch s. When second and fourth sections b, d contact the spring 24, the latter makes contact only with a second contact 28 of switch s. When a third section c contacts the spring 24 the latter remains in engagement with the second contact 28 which itself is moved into contact with a third contact 29 of the switch s. In association with switch s are ganged switch sections 30, 31, 32 and 33 each having a travelling contact controlled by a knob 30a and four stationary contacts. Some of the stationary contacts are connected with one another and with the contacts 27, 28 and 29 of switch s and the third contacts of the third and fourth switch sections 32, 33 are connected with the autotransformer 9 by a conductor 70 directly and the conductor 70 and a resistor 74 respectively. The travelling contacts of the first and second switch sections 30, 31 are connected to a conductor 40 in the plate circuit of a triode 16 in one oscillator unit 3, the travelling contact of the third switch section 32 is connected to a conductor 41 in the plate circuit of a second triode 17 in the other oscillator unit 4 and the travelling contact of the fourth switch section 33 is connected with the filament circuit of the two triode valves 16, 17 which is energised by a secondary winding 13 of the autotransformer 9. Transformers 75, 76 are included in each of the oscillator units 3, 4. Each transformer 75, 76 comprises cores 77, 78, 79, one side of each core being adjacent one side of each of the other cores to form a common primary core 80. Each primary core 80 carries two windings 38, 39, 43, 44 in the grid and plate circuits respectively of the triodes 16, 17. Secondary windings of the transformers 75, 76 are connected with the output circuits 5, 6. With the travelling contacts of the switch sections 30, 31, 32 and 33 in contact with the first stationary contacts, the first and third contacts 27, 29, of the switch s are both connected to the conductors 40, 41 of the oscillator units 3, 4. The contacts 27 and 29 will be intermittently and alternately energised as the cam 25 rotates and this produces 40 surges per minute in the oscillator units 3, 4, which may be applied to the body from any one of the outputs 49, 54 of the output circuits 5, 6. When the travelling contacts contact the second stationary contacts of each switch section 30, 33 so that the third contact 29 of the switch s is connected only to the conductor 40 of one oscillator unit 3 and the first contact 27 is connected only to the conductor 41 of the other oscillator unit 4. With rotation of the cam 25 the oscillator units are energised alternately and each at the rate of 20 surges per minutes. If one of the ouput circuits 5 associated with one oscillator unit 3 is connected with a flexor muscle or muscles and the other output circuit 6 associated with other oscillator unit 4 is connected with an extenor muscle or muscles, the flexor and extenor muscles are stimulated alternately with the resultant movement of the part of the body associated with them. When the travelling contacts of the switch sections 30, 33 contact the third stationary contacts, conductors 40, 41 of oscillator units 3, 4 are each connected directly to the autotransformer 9 by a conductor 70 and also the filaments of triodes 16, 17 are connected with the same conductor 70 through a resistor 74 and another conductor 48. Oscillations thus produced in the oscillator units 3, 4 and applied to the body give a vibratory sensation. When the travelling contacts make contact with the fourth stationary contact of each switch section 30-33 the conductors 40, 41 of the oscillator units 3, 4 are both connected to the second contact 28 of the switch s so that as the cam 25 rotates the plate current of triodes 16, 17 is controlled only by the spring contact 24 and the second contact 28. A slow surge at the rate of 20 surges per minute is produced which may be applied to the body through either output circuit 5, 6. An electric motor having a speed other than 20 r.p.m. may be used giving a corresponding difference of surge rate in the output circuits 5, 6. Neon lamps 68, 69 are provided to indicate when the conductors 40, 41 of the oscillator units 3, 4 are energised.