GB1488957A - Apparatus for electric pulse stimulation - Google Patents

Abstract

1488957 Pulse stimulators STIMULATION TECHNOLOGY INC and A C HYMES 28 Feb 1975 [1 March 1974] 8448/75 Heading A5R An apparatus for treating pain or inducing the return of arrested body function, resulting from surgical or accidental trauma, comprises a pulse generator, Fig. 4, producing e.g. square pulses, at a repetition rate of between 10 and 300 pulses per second, the pulse width being variable between 50 and 1000 microseconds, at least one current source connected to the pulse generator and supplying current adjustable in the range of between 10 and 80 mA amplitude independently of a load connected thereto, and at least one pair of flexible, elongate electrodes 10, 11, Fig. 1, e.g. of aluminium foil with an insulative backing of clear vinyl material, connected to the current source and each having a current conduction area of 3 to 30 square inches, the electrodes being secured to the skin of a patient within a localized area of trauma during the use of the apparatus, as shown (Fig. 1). Preferably, an electrically conducting gel is applied to the electrodes. The frequency of the rectangular pulses produced by a free running multivibrator comprising transistors Q 1 , Q 2 , is controlled by a variable resistor R3, whereas the pulsewidth is adjusted by varying the time-constant of an RC network comprising a variable resistor R11 and a capacitor C4. Transistors Q6, Q7, and Q8 amplify the pulses appearing at the base of the transistor Q6, and a potentiometer R15 adjusts the amplitude of the pulse.