GB798944A - Conveyor system - Google Patents

Abstract

798,944. Controlling the movements of load-carriers in conveyer systems or shoots. STAATSBEDRIJF DER POSTERIJEN, TELEGRAFIE EN TELEFONIE. Nov. 25, 1954 [Nov. 27, 1953], No. 34229/54. Class 78 (1). Load-carriers which are moved along a system of channels either by gravity or by an underlying endless belt are spaced as they approach a junction between a main channel and a branch channel by temporarily stopping a following carrier under control of a preceding one, and means is also provided for stopping carriers in the main channel when carriers in the main channel are approaching the junction. As shown, carriers are moved in a main channel 202 and a branch channel 201 either by gravity or by underlying endless belts. Channel 201 is provided with a spacer consisting of a rocking lever having a roller 206 at one end which is moved aside by a carrier 204 passing between this roller and a fixed roller 209 so as to move a detent 207 at the other end of the lever into the path of a following carrier 205, the detent being withdrawn by a spring when carrier 204 has passed beyond roller 206. A similar rocking lever having a roller 215 and a detent 216 operates on carriers 212, 213 in channel 202. In order that carriers in channel 201 may have precedence over those in channel 202 an additional rocking lever carrying a detent 220 is provided in channel 202 and is adapted to be rocked by an electromagnet 219 to project the detent 220 when the carriers 204, 205 are passing roller 206 at less than four-second intervals so that carriers 212 and 213 in the main channel are stopped by the detents 220 and 216 respectively while carriers 204, 205 are transferred by a curved guide wall and a driven conical roller 210 to the main channel 202. The control circuit for electromagnet 219 includes contacts 217 and 218 which are closed when the respective rollers 215, 206 are engaged and which operate slugged relays 340, 330 respectively. Operation of relay 330 energizes a relay 350 through contacts 331 and resistance 380 this relay remaining locked in by its contacts 353 until shorted out by contacts 371 of a relay 370 having a four-second delay. The latter remained de-energized when contacts 331 and 353 closed owing to the opening of contacts 332 of relay 330. However, when relay 330 releases contacts 332 re-close energizing relay 370. Contacts 371 which would short relay 350 do not close for four seconds and during this period relay 350 remains energized and its contacts 351 provide a shorting circuit for a relay 360, controlled by contacts 341 of relay 340, through normally closed contacts 361 of relay 360 and a resistance 381. If during this period contacts 217 are closed contacts 342 complete a circuit to the electromagnet 219 to stop the carrier 212. Electromagnet 219 remains energized if relay 330 is re-energized in consequence of another carrier closing contacts 218 within the four-second delay of relay 370 since the latter is de-energized, the circuit shorting relay 360 being held in by contacts 353 in case contacts 371 close temporarily at this point, and after release of contacts 353 relay 370 will be re-energized and another four-second delay will commence. After the expiration of four seconds contacts 371 close, shorting relay 350 and opening contacts 352, whereupon electromagnet 219 is de-energized to release carrier 212. By the opening of contacts 351 relay 360 is allowed to be energized so that if contacts 217 are again closed by a following carrier 213, contacts 361 and 362 are opened to allow this carrier to pass.