Patent GB-503729-A (GB)
Title: Improvements in and relating to exchange stations for tubular conveyor systems
IPC: B65G51/42
Filed: 1938-08-30
Abstract: 503,729. Pneumatic dispatch-apparatus. TELEPHON-APPARAT-FABRIK E. ZWIETUSCH & CO., GES. Aug. 30, 1938, No. 25405. Convention date, Oct. 26, 1937. [Class 78 (i)] In an automatic tubular conveyer exchange station having a number of incoming tubes leading to a common collecting tube connected with a number of outgoing tubes by way of a junction arrangement controlled by pre-adjusted members on the travelling carriers, a carrier, intended for an outgoing tube which is already occupied is automatically directed into a byepass tube which leads it back to the exchange station. In Fig. 1 incoming tubes a ... e, each provided with a number of sending stations and a carrier separating device Ta .. Tn, discharge into a collecting hopper Tr. A common collecting tube S connects this hopper with a multiple junction GW controlled by contacts k on the tube S, which contacts are selectively engaged by pre-adjusted contact rings r on the carriers. These contact rings are in two groups adjustable respectively to positions for the selected outgoing tube a<1> ... e<1>, and the individual stations (e.g. A], A2, A3) on each tube. In addition to the outgoing tubes a<1> ... e<1>, the junction GW has a byepass tube n leading back to the collecting hopper Tr. Each carrier is temporarily arrested in the tube S by a magnet HM to allow its contacts to set the junction GW and select the appropriate receiving station, this being effected.by a series of main junction relays, one of which is energized according to the individual receiver station junction relays, one of which is energized according to the selected receiver. The main junction relay de-energizes as the carrier passes travel contacts, (e.g. a, k) at the entrances to the outgoing tubes, whilst the receiver station junction relay de-energizes when the carrier passes travel contacts (e.g. kal) at the receiver station. As long as the receiver station relay remains energized, a two-way switch isolates the main junction relay of the corresponding outgoing tube, and prepares, in place thereof, the circuit of a junction relay for the byepass tube n. If, therefore, a second carrier intended for an outgoing tube which is already occupied arrives in the tube S, it is directed to the byepass n and led back to the hopper Tr to be dealt with later. In the absence of the byepass n, a carrier destined for a different receiver station on the same outgoing tube as that of a previous carrier, would be held up in the tube S until the previous carrier has passed the travel contacts at its receiver station. The invention avoids this interruption in the operation of the exchange. In the modified arrangement of Fig. 2, separate sets of contacts k for interpreting the destinations of the carriers are arranged in separating devices Ta ... Tn at the ends of the incoming and byepass tubes, instead of a single set in the tube S. A rotary selector brings these sets of contacts into operation in succession. If a carrier intended for an occupied outgoing tube enters a separating device, and if a further carrier lies behind it, and this is detected by travel contacts fka .. .fkn, thecarrier in question is released and diverted by junction GW to the byepass n as before. If, however, no further carrier is present, it is held back and the rotary selector passes on to the next separating device so that no delay in operation occurs.