Patent GB-266529-A (GB)
Title: Improvements in timing devices for centrifugal separators
IPC: B04B9/10
Filed: 1926-02-10
Abstract: 266,529. Alliott, E. A., and Manlove, Alliott, & Co., Ltd. Feb. 10, 1926. Driving.-A controlling device for centrifugal extractors and separators has a driven member adapted to be clutched to a driving member, and is provided with means for de-clutching automatically at the end of the movement and returning the driven member to its initial position. The clutch and switch mechanism is enclosed by a casing 1 which is entered by a shaft 5 driven through reduction 3 from the driving motor, or any suitable part of the separator. An iron disc 6 is secured to the end of the shaft 5 and forms the driving member of an electromagnetic clutch. the other element being formed by a disc 45 and electromagnet 7 on the shaft 9. The end of the shaft 9 is squared and carries a disc 8 having a projection 19 and a radial indicator arm 10; in the initial position of the apparatus, a spiral spring 18 holds the disc in position with the arm 10 in contact with a stop 15 on a cap 11 provided with a glass window 12 and a pointer 16. By rotation of the cap 11, the pointer 16 and the arm 10 can be set to any position on the scale 14; it is then held by the clamp 53<1>. The solenoid 28 is mounted on a bracket 56 and has an armature 29 on a pivot 57 and connected to the plunger rod 58<1> of a dashpot 59. A spring switch blade 34 is closed by the release of the armature 29 and remains closed until its spring and the weight of the dashpot cause it to open against the retarding influence of the dashpot. The switch 32 is normally closed by its own spring action and the switch 23 is held closed by a shoulder 22 on the back of the lever 20. The circuit connections are shown in Fig. 6. The cap 11 is set to enable the machine to run for a predetermined time, or number of revolutions. When the main switch 73 is closed a circuit is completed through the lamp 78 to indicate that the machine is stationary. The push-button 77 is depressed to start operations and current passes through the starter 75 and the motor 76. thus setting the separator and the reduction gear 3 in motion. Simultaneously, the solenoids 7, 28 are energized and the lamp 79 indicates that the machine is running. The solenoid 7 operates the clutch and the disc 8 with the projection 19 and arm 10 starts to revolve. The solenoid 28 Operates the armature 29, which opens the switch 32 to extinguish the lamp 78; it leaves the switch 23 held closed by the cam 22, and it extends the dashpot 59. At the end of the set period the projection 19 strikes the upper end of the arm 20, which causes the cam 22 to release the switch 23; this cuts off current from the starter and the motor and separator consequently stop. The starter re-sets itself, but the solenoid 7 is de-energized, and the clutch disc 45 with the disc 8 and its attachments are returned to their initial position by the spring 18; lamp 79 is also extinguished. The solenoid 28 is de-energized and the armature 29 is raised by the spring 82; the switch 32 closes and the lamp 78 lights up. The armature also raises the dashpot to close the switch 34 to sound the horn 80 during a short interval, after which the dash-pot drops and the switch opens. In the final position the switch 23 is again held closed by the cam 22 on the arm 20 and the apparatus is ready for a fresh operation. When the arrangement is applied to a washing machine an additional solenoid is employed to control the discharge door.