Patent GB-436547-A (GB)
Title: Improvements in or relating to means for indicating data relating to the rate of working of factory or other operatives
IPC: G07C3/08
Filed: 1934-04-14
Abstract: 436,547. Indicating-apparatus. ERICSSON TELEPHONES, Ltd., 67, Kingsway, London, and ENGBLOM, J. F. T., Villa Tomoana, Elm Avenue, Beeston, Nottingham. April 14, 1934, No. 11285. [Class 106 (iv)] Means for indicating data relating to the rate at which operations are performed by operatives comprises a step-by-step electromagnetic switch controlled by contacts operated as a result of the operations, a similar switch controlled by time impulses, and means for comparing the positions of the two switches after a predetermined number of steps has been made by one of them. The pieces to be dealt with by an operative are arranged in compartments in a rotatable tray 1 divided into eight sections. When the work on the pieces in a section is completed the operative depresses a pedal 14 whereupon the tray is rotated through one-eighth of a revolution to bring the next section to the front. Contacts ON, Fig. 2, are closed when the tray is in its initial position and are open during the rest of its rotation. Contacts IS are closed momentarily as the tray passes from one position to another. When a starting key STK is depressed current is supplied to relays CS and C, relay C operating first. The contacts ON relating to each operative are connected by lines 21 to the first bank dw1 of a distributing switch. If, when STK is closed, the wiper dw1 happens to be connected to contacts ON which are closed (because the corresponding tray is in its normal position), a circuit ON, 21, dw1, interrupter ddm for the distributer, contacts c1, distributer controlling magnet DDM and relay C is completed. The magnet DDM thus advances the wiper dw1 one step. This continues until dw1 finds a contact connected to contacts ON which are open. No circuit for DDM is then completed, C opens and the wiper dw1 remains on the selected contact. When the tray is returned to normal position, the contacts ON are closed and the testing operation proper commences on the selected tray. The time-counting switch. This comprises wipers tw1 ... tw4 and is operated by a magnet TDM controlled by the contacts ba3 of a relay BA arranged in the circuit shown in Fig. 4. When the testing operation proper commences, a circuit is established from the contacts ON to line 21, wiper dw1, contacts c1, hc2 and cs2 to relay ST. Contacts st3 of ST then energize relay BA which in turn energizes relay BB to cause a spring 26 to close contacts 27. A circuit st3, 27, 26, ba1 to relay BC is then made. Contacts bc1 of BC then release relay BA, contacts ba3 then opening so that magnet TDM moves the time switch one step. Relay BB is also de-energized, by the opening of contacts ba2, the spring 26 being released and commencing to vibrate between contacts 27, 28. When the vibrations have decayed to a predetermined extent, slow-operating relay BC releases, contacts bc1 open and the cycle recommences. During each such cycle the time switch advances by one step, the time taken for the cycle being determined by the adjustment of the spring 26. The operations-counting switch. At each movement of the tray 1 a circuit is made from contacts IS to line 22, wiper dw2 and contacts st2 to a relay OR. Wiper dw2 is comprised in a switch which includes dw1 and dw3 .. dw8. Relay OR closes contacts or1 to cause the advance of the operationscounting wipers ow1, ow2. It is assumed that the operative being tested corresponds to the 13th position of the distributing switch dw1 and that each step of the time switch tw occupies 0À2 minutes. It is further assumed that the first four steps of the tray should be made in 3À2 minutes and the total of eight steps in 6À0 minutes. Conductors 29, 30 are then arranged to connect dw5 and dw6 to those positions of the time switch tw3 and tw4 representing 3À2 and 6À0 minutes respectively, while dw7 is connected to point 4 on the operations switch ow2 and dw8 is connected to point 8 thereof. If the operative completes the first four operations in less than the set time of 3À2 minutes, a circuit is established from relay A through dw7, 31, ow2 and st6, A holding via contacts a2. When 3À2 minutes have elapsed, a circuit st4, tw3, 29, dw5, so1, a1 and relay FA is completed. Relay FA operates to complete a circuit st4, so2, 33, resistance R2, fa1, dw3, 23 and upper winding of relay F to battery. Relay F brings in a circuit from cs3, 25, lower winding of relay F, s 1 and f2 to a green lamp L and to battery. Contacts f3 close a meter circuit FM, but the meter is not actuated because of the presence of the resistance R2 in the circuit. If the operative completes the whole eight operations in less than the set time of six minutes, the following circuit is completed: Relay B, dw8, 32, ow2, st6, R1 to battery. Relay B operates and holds via b2 while contacts b1 change over so that, at the end of six minutes, relay FA re-operates via b1, sa3, fa2, dw6, 30 tw4 and st4. Late-operating contacts fa2 then open so that relay HC operates to close contacts hc3 to short-circuit resistance R2, the meter FM then being operated. The green lamp L1 remains alight. If the operative exceeds the set time period for completing the first four operations, a relay SA is operated via st4, tw3, 29, dw5, so1 and al. A circuit is then established from line 33 through R2, sa2, dw4, line 24 to relay S. This closes contacts s2 to light a red lamp L2 and opens contacts s1 to extinguish the green lamp L1. A meter SM is not at this time operated on account of the resistance R2. If the set time of six minutes elapses before all the eight operations have been completed, relay SA re-operates and late-operating contacts sa3 remove the short-circuit across relay HC which operates to close contacts hc3, the meter SM then being actuated. Means are described whereby the switches are returned to normal and the apparatus then proceeds to test the next operative whose switch ON is found out of its normal position by the distributer dw1. If it is desired to test a particular operative, a " camping-on " key CK is depressed and the distributer is stepped-on by operating a key SK a number of times to advance the wipers dw1 .. one step at each depression until they reach the contact corresponding to the operative concerned. Tests are then repeatedly made on that operative.