GB220051A - Improvements in or relating to electric time-element devices - Google Patents

Abstract

220,051. Reyrolle & Co., Ltd., A., and Linstow, F. N. May 5, 1923. Switches, actuating; retarding and time-limit devices.-A multiple time-element device for use in a power station comprises a single driving member, a number of dissimilar and separate time-element devices, and an operative driving connection for each device which is suited to the particular characteristics of the device and by means of which the device can be brought into or out of operative engagement with the common driving member, which may be a shaft rotated at a slow and uniform speed. As applied to automatic and semi-automatic substations, and referring to Fig. 1, a motor A drives a shaft B carrying pinions I3<1> - - B<4> which are caused to be engaged by pinions E, E<2>, E<1>, E<3> of time element devices C, C<2>, C<1>, C<3>, respectively, by means which may be an electromagnet inside the casing of each device. The time-elements C, C<2> have on their spindles cam discs F, F<1> acting through levers G, G<1> on contacts H, H<1>, and are provided with re-setting springs J, J' respectively, which are wound up by rotation of the spindles and rotate them in the opposite direction when the gears are disengaged. The time-elements C<1>, C<3> operate their contacts through cams F<2>, F<3> driven through worm gear K<1>, K<2> and may be re-set by springs acting either directly on their spindles or, if the worm gear is reversible, on the cam spindles. In the arrangement shown in Figs. 2 and 5, the motor A' drives the shaft A<2> carrying pinions B<5> - - B<7>, of which B<5> can be engaged by either or both of the gear wheels E<4>, E<3> by means of the armatures L, L' of electromagnets L<2>, L<3>. The gears E., E' form part of devices which are employed, respectively, in connection with the synchronizing of the substation generator, and with an overload relay. The spindles carrying the wheels E E<@> carry cams F<4>, F<3> acting through levers G<4>, G<3> and G<6>, G<7> on contacts H<4>, H<3> and H<6>, H<7> respectively, as shown in Fig. 4 wherein the spindle E<6> slides in the cam F<5> against the action of an adjustable spring D<1> and the lever G<6> acts on contacts H<6> through a lever G<6>*. The re-setting spring J<2> is housed within the cam F<5>. The two other time-element devices are driven through worm reduction gear. The cam drum F<6> of one, which is intended for controlling the starting-up circuits for the substation generator, is driven by the worm M, with which is in sliding engagement the spindle E<7> carrying the wheel E<8> which is moved into engagement with the wheel B<6> bv the armature arm L<5> of the electromagnet L<4>. J<3> is a re-setting spring. The cam F<6> has three surfaces F<7> - - F<9>, each cooperating with a contact-operating lever, and the surface F<9> is adjustable by means of a nut F<10>. The cam drum F" of the other device is likewise operated through a worm M<1>, spindle E<9> and wheel E<10>, the spindle being moved by the armature arm L' of an electromagnet L<6> into engagement with pinion B<7>. Reversing mechanism is provided for the drum F", which controls an underload relay controlling the shutting-down circuits for the substation generator, and comprises pinions B<8>, B<9> mounted on a pivoted lever B<10> and driven from the pinion B<7>, the spindle being movable so that the gear wheel E<10> engages either with the pinion B<9> or directly with the pinion B<7>. The reversing movement is stopped, when the drum F<11> reaches the zero position, by a pin B<11> engaging a. recess F<19> in the cam ring F<12> so that the lever rocks and disengages pinions B<7>, B<8>. The drum F<11>has three surfaces F<12> -- F<14>, of which F<14> is frictionally driven from the drum F" by a spring F<15> and carries a projection F<16> working between stops F<17>, F<18>. Thus operation of the contacts H<10> controlled thereby is ensured at the beginning of the forward or backward movement of the drum F<11>. The cams may operate mechanicall3À locking or tripping devices either independently or in conjunction with circuits, so that, when operated, such trips or circuits cannot be re-operated until reset independently or by hand. For instantaneous re-setting of the device the spring may act directly on the spindle, but for average re-setting the spring drives the spindle back through the gear.