| 摘要 |
402,589. Electrostatic switches. RAHBEK, K., 17, JagtvÚj, Copenhagen. Nov. 7, 1932, No. 31354. Convention date, Nov. 10, 1931. [Class 38 (v).] Relates to switches and other apparatus of the kind described in Specifications 144,761, 146,747, 151,997, and 194,747, [all in Class 38 (v), Electric switches &c.], which utilises the electrostatic attraction produced by an electric current passing between two bodies in contact, at least one body being a semi-conductor such as agate, wood, gelatine &c., and consists in using only alternating currents of form other than ordinary single phase current so that no permanent electro-chemical changes occur. In one embodiment an interrupter 5, Fig. 1, produces a square wave form alternating current to be applied to the device 1, 2 ; alternatively a contact 20, Fig. 3, may be actuated by a cam 23 to oscillate between contacts 21, 22 to change the direction of the current and govern the duration of each impulse. When sinusoidal alternating current is employed, a glow lamp 9, Fig. 5, may be used which discharges before the peak voltage is attained and produces a flat top to the wave form. In further modifications, poly-phase currents are used, Figs. 7, 8 and 9, not shown. According to the Specification as open to inspection under Sect. 91, sinusoidal alternating current may be used. This subject-matter does not appear in the Specification as accepted. |
