Patent GB-261078-A (GB)
Title: Improvements in or relating to electric switchgear
IPC: H01H3/30
Filed: 1925-08-10
Abstract: 261,078. Reyrolle & Co., Ltd., A., Coates, F., and Mirrey, J. Aug. 10, 1925. Oil switches; automatic circuit-breakers; switchgear arrangements; electric motor actuation; indicators.-Electric switchgear comprises the combination with two or more oil-immersed switches, of an actuating mechanism for each switch, an electric motor or other driving unit common to all the switches, and means for selectively bringing the mechanisms into operative engagement with the driving unit. Referring to Fig. 2 the motor A drives through gearing a gear B adapted to be clutched, when the motor is up to speed, to a shaft C by means of a clutch B<2> which may be magnetic or electrically operated by a governor A<4> on the motor shaft. The shaft C carries a gear C<1> for each switch meshing with a gear C<2> carrying a disc C<3> to which is pivoted eccentrically at D<1> a slotted link D, in the slot of which engages a pin E<2> on a vertically sliding rack E engaging a pinion E<3> on the switch-actuating shait E<4>. Normally when the shaft C rotates, the slot is long enough not to move the pin E<2>, but energization of the solenoid F<2> of the switch moves a lever F about its pivot F<1> against spring action so that the pin is driven, the rack thereby rotating the shaft E<4> to close the switch. A nut D<3> varies the length of the link and a spring between it and its pivot D takes up small inaccuracies. On closure of the selected switch, its solenoid F<2> and the clutch B<2> are de-energized and the motor stopped. The switch is tripped open in the usual way and restores the rack. In another form, the motor A is directly geared to the shaft C and the disc carrying the slotted link is on a shaft to which it is adapted to be coupled by an expanding ring-clutch by the selected solenoid. In Fig. 7 the motor is connected by a solenoid operated clutch to gearing, to two like members L, of which one behind the other are pivoted links L<2> connected through balanced springs L<3> with a pair of parallel driving bars M. one behind the other, common to all the switches. The bars are in sections with swivelling connections M<1> between them and reciprocate on rolling when the motor drives the gears L. Pivoted to the bars are a number of arms N, one for each switch, each being adapted to be raised by a solenoid-operated stirrup N<1> to abut the end of a rack N<3> driving the switchactuating shaft N<6>. When a particular switch is to be closed, the appropriate solenoid N<2> is energized, and after closure the mechanism is allowed to run another half-revolution to restore the bar M. In Fig. 9, the motor O is used to operate an energy storing device, for example, a spring or weight, which is allowed to give up its energy to close the switch. The motor O has an electrically-controlled friction brake O<1> and acts through gearing and a crank on a barrel P<1> containing a spring P connected with a sector Q, which is in turn connected to a toggle Q<5> controlled by a toggle Q<6> and solenoid Q<7>, and meshes with a rack on the bars. By energizing the solenoid Q' and tripping the toggles Q<5>, Q<6>, the spring P will expand and move the bars to close the selected switch, as in the previous form. On closure, the motor is started up by auxiliary switch mechanism and compresses the spring P which is held by the reset toggles. In Fig. 12 a separate energy-storing device is provided for each switch, and a single motor drives a shaft common to all the switches, each of which is geared to it by a gear T<4> carrying a crank T<5> and slotted link T<6>. The barrel U' contains a spring which is connected to the link T' by arms U<4> and a pin U<5> engaging the slot. As in the form shown in Fig. 12, a solenoid T<9> is energized to move an arm T<2> so that the spring is compressed and held by a toggle (not shown) connected to a rack U' on the arms U<4>, the rack acting on a shaft V<1> to close the switch. The latter shaft is clutched to the switch-actuating shaft V<6> by means of a clutch controlled by a spring V<7>. The switch is closed by energizing the appropriate solenoid to break the toggle above referred to, and on closure, the solenoid T' is energized to compress the spring and reset the toggle, the clutch being disengaged. After one revolution of the crank T<5> the motor is stopped and the solenoid T<9> de-energized, and when the switch is tripped open, the shaft V<6> is rotated to engage the clutch ready for closure. Fig. 13 shows the general arrangement of a switch and its rack operated shaft, and illustrates as an example the circuits employed with the switch of Fig. 9. Three-phase gear of the horizontal draw-out type comprises a draw-out part movable on rollers relatively to a fixed part, the latter comprising two rows of three sockets, the upper of which are connected by ropes W<13> with a spindle X carried by arms X<1> on a shaft X<2>. The spindle X carries also arms X<3> with rollers X<4> engaging recesses in a cam-shaped block X<5> rotatable on a spindle X<6> carried on the ends of cranks X' on a shaft which is coaxial with that X<2> and is geared to a shaft X<10>. When the draw-out part is rocked in, the latter shaft engages the shaft S' (Fig. 9) having a spring X<12> for opening the switch. Each block X<5> carries an arm X<13> held by a toggle X<14> while a spring catch X<15> engages a. stop X<16> in the closed position. Rotation of the shaft S' rotates the arms X<3> to close the switch, which is held by a catch X<15>, the toggle X<14> holding the arm X<1>. The opening is effected by trip means (not shown) breaking this toggle, and freeing the rollers, and springs (not shown) move the contacts off while the spring X<12> returns the shaft X', resetting the toggles X <14> ready for reclosing. Spindle X<2> operates a change-over switch Y<7>, one circuit of which may be for indicating, while the other is connected to the solenoid S<2> (Fig. 9) and a selector switch Z<2> having a contact associated with each switch to be controlled. A switch Z<5> connects in circuit either the solenoid Q<7> or motor and brake, the former circuit being controlled by a switch hand Z<8> which is interlocked with Z<2> to prevent closure unless the latter is closed. Switch Z<5> is operated in one direction by the toggle Q<5> and in the other by the motor crank 0<5> through suitable mechanism (not shown). The circuits shown are those of the open position of the main switch. To close, the switch Z<2> is moved to energize the appropriate solenoid S<2> through switch Y<7> and Z<8> to energize Q<7>, which closes the main switch and cuts out solenoid S<2>. Switch Z<5> also is moved to cut out solenoid Q' and start up the motor and, when the spring is compressed, it is moved back and stops the motor ready for the next closure.