GB172933A - Improvements in electro-therapeutic apparatus - Google Patents

Abstract

172,933. Sanche, C. M., (Assignee of Gleeson, T. W.). Dec. 17, 1920, [Convention date] . Regulating transformers.-An appliance for electrotherapeutic treatment comprises a casing enclosing a self-induction coil in circuit with an interrupter, and fitted with externally operated means for varying the frequency and intensity of the current impulses communicated to a series of studs on the casing forming electrodes arranged in separate series of opposite polarity. Handles or other movable electrodes may also be connected to the casing by flexible conductors. In the form shown, a metal casing 1 is formed with a separate base member 2 of insulating material through which project a number of metal studs or electrodes 46, 47 of opposite polarity. The casing contains an electromagnet comprising a coil 6 (see diagram, Fig. 14) and a core 7 coacting with a pivoted armature 10 controlled by a spring 11. The moving contact 16 of the interrupter is mounted on a spring 18, which in engaged by an adjustable nut 24 on a rod 23 carried by the armature 10. The leads to the electrodes 46, 47 and to a pair of detachable electrodes 50 are connected to binding posts 42, 43 connected respectively to the interrupter contacts 16, 17. The speed of the interrupter is varied by turning a button 31, the stem of which carries a cam 35, Fig. 14, which bears against the armature 10 to limit its movement away from the core 7. The intensity of the current impulses in the electrode circuit is varied by turning a button 54 which is connected to a contact 57 travelling on a rod 60 and engaging a coil 53 of thick wire which surrounds the inductance winding 6 and is wound in a direction opposite thereto. The induced current in the coil 53 sets up, through the medium of its own magnetic field, a counter current in the inductance winding which serves as an impedance which may be regulated by more or less short-circuiting the coil 53 by adjustment of the contact 57. The primary circuit of the electromagnet is connected through a socket 14 on the casing and a plug terminal, Fig. 12, to a battery and is controlled by a press-button switch 30 on the casing.