Patent GB-1268668-A (GB)
Title: System for automatically transferring a vehicle from any one to another of different paths of operation
IPC: B65G1/04
Filed: 1969-03-28
Abstract: 1,268,668. Control of motors; two-part couplings. WESTINGHOUSE ELECTRIC CORP. 28 March, 1969 [5 April, 1968], No. 16326/69. Heading H2E and H2J. [Also in Division G3] An automatic warehousing arrangement comprises a number of storage racks 10-13 associated with a stacker crane 16, the racks having cubicles 24 with rails 25 adapted to support load pallets 26. Crane 16 is moved along an aisle by motor-driven car 31 disposed on rails 29, 30, and having masts 35, 36, for supporting a cage 37. A transfer trolley 63 is adapted to move the crane from one aisle to another whereby a plurality of aisles is serviced by a single crane. Cams 41 actuate limit switch 45 positioned on the crane, whilst cam 42 is a transition actuator for switch 46 which may also be actuated by over-travel cam 43 on the trolley. Cam 44 on the trolley actuates relay control switch 47 on the crane. A solenoid-operated microswitch 48 and photo-detector 33 cooperate with a light source 34 to control transfer of the crane to and from an aisle. Car 31 carries a drive motor 50 and hoist motor 51, power for the control circuits being supplied by cable 52 from source 53. A cable 55 is festooned along rail 57 and is connected to computer 58, and to the crane through coupling 60, 61, associated with lock 62. Trolley 63 is driven along rails 67 by motor assembly 69 receiving power through cable 70 from the units 53 and 58. Rails 77, 78, may be aligned with rails 29, 30, whilst trolley lines 52, 52A, are also aligned. For this purpose, latch motors 79 drive a pin into a hole in the rack adjacent to a transfer point.  The motor assembly 69 comprises pairs of high and low-speed A.C. motors, reverse-current braking being provided, Fig. 6 (not shown). A manual-automatic selector switch controls relays for positioning the trolley and for indicating whether the crane is nested in the trolley, Fig. 7 (not shown). Computer control relays are energized under the command of a programme to initiate travel of the trolley along the transfer course or to initiate travel of the crane off the trolley. The position of the trolley is automatically determined by groups of cams disposed along the transfer course for actuating microswitches located on the trolley for feeding signals back to the computer, Fig. 8 (not shown). When the crane is to be transferred from one aisle to the next in a forward direction, the presence of the crane nested on the trolley is signalled to the computer which issues a command to energize a high-speed relay. As the trolley approaches the desired position its speed is reduced until the centre of the selected aisle is reached. Information returned to the computer enables movement of the crane from the trolley into the aisle, and to permit mating of the connector parts. Closure of timer contacts establishes the circuit to start the crane off the trolley, the connector parts being then locked. The photo-detector closes contacts which shunt the limit switch 46, to allow movement of the crane in the aligned position when being returned to the trolley. When the crane is nested on the trolley, a memory relay is released to permit the crane to remain inactive until a further transfer command is received, Figs. 9, 10 (not shown). Plug-and-socket arrangement.-The lock mechanism 62 comprises springs 88 mounted on screws 84 and bearing against stands 82 and nuts 87. The other side of each nut engages connector 89 secured to stop bar 93 supported on axle 94. A lock-bar 95 straddles rail 57. The pull exerted by cable 55 causes bar 95 to bear against bar 93, but the force is insufficient to overcome spring 88. When the crane approaches a transfer position, bar 93 pivots against spring 98, the connector parts being held together by a latching mechanism. When the crane is being transferred from the trolley to an aisle, springs 88 resist movement of bar 93 about axle 94 upon initial contact of parts 60, 61, permitting them to be joined with a strong latching force. Continued movement of the crane overcomes springs 88 and forces bar 93 to clear bar 95 and permit free movement of the cable. Socket 60 includes body 101 integral with arm 102 supporting bar 95 and rollers 103, 104. Insulator 108 supports spring contacts 109 which are connected by conductors 110 to terminal strips 111 serving as terminating points for conductors 113 of cable 55. Bore 123 is adapted to abut surface 124 of plug 61, an alignment pin 125 being provided. The plug has insulator 127 supporting contacts 128 which are connected through conductors 129 to terminal boards 121, the conductors passing through hollow shaft 130. Latch members 134 each comprise solenoid 136 for actuating trip bar 137. Microswitches 144 are operated by arm 147 engaging face 122. The plug 61 includes a backplate 148 attached to the frame structure of the - crane. The latch 134, may be replaced by a mechanical latch, the trip bar 137 having a camming surface 142A.