Patent GB-786904-A (GB)
Title: Improvements relating to recording equipment
Inventor: REDDING ROBERT JAMES
IPC: G08B23/00
Filed: 1955-05-20
Abstract: 786,904. Recording-apparatus. EVERSHED & VIGNOLES, Ltd. May 22, 1956 [May 20, 1955], No. 14641/55. Class 106 (4). Recording-apparatus comprises a solenoid SA1 energized upon the occurrence of a predetermined condition in a physical system to record an identifying mark on a normally stationary record surface, a solenoid 50 simultaneously to record the time and driving mechanism 60 set in action immediately afterwards to advance the record surface. Fault conditions in eight variable quantities may control eight pairs of contacts supplied in parallel from a secondary winding 13, the first pair being connected by lines 9, 10 in a circuit including a rectifier 16 and relay A energized under normal conditions with the contacts 1 closed. Upon the opening of contacts 1 relay A is de-energized and the change-over of switches A1, A2, initiates charging of a condenser AC2, while a condenser AC1 discharges through solenoid SA1, causing a characteristic mark to be made in red, while the subsequent closing of the contacts 1 upon a return to normal changes over the switches A1, A2, initiating charging of condenser AC1 while condenser AC2 discharges through solenoid SA2, causing the same characteristic mark to be made in black. With each change over of the switches A1, A2 a switch A3 momentarily completes a circuit over line 22 to discharge a condenser 33 and remove the bias from the grid of the half 26 of a double diode, the consequent rise of potential of its anode passing to the grid of the other half 27 which then conducts and energizes a relay RY until the condenser 33 recharges and the half 26 conducts again cutting off the half 27 and de-energizing the relay RY. The period of energization of the relay RY is predetermined by the setting of a variable condenser 35. The changeover of switch RY1 causes three condensers 53 to discharge through the solenoid 50 causing recording from a time stamp driven by a motor 51. Closing of switch RY2 energizes relay RZ and closing of switch RZ1 starts the record surface driving motor 60, the slight delay allowing the record to be made before the surface moves. The surface moves for the predetermined peiiod it takes the condenser to recharge and if a further fault occurs during the period, the condenser discharges and the period of movement starts again, thus spacing apart records of faults occurring in rapid succession to make the order of their occurrence clear. Once a day a cam 76 driven by the time stamp motor 51 closes a circuit to a relay RX. Contacts RX1 open, simulating a fault in all the variable conditions with recording of all the characteristic marks and of the time, but switch RX2 opens the circuit to relay RZ so that the record surface does not move. At the end of the predetermined period for the condenser 33 to recharge the relay RY is deenergized opening the circuit to relay RX so that contacts RX1 close again simulating return to normal of all conditions with consequential recording of characteristic marks and time followed by advance of the record surface. The line of marks across the record surface will indicate a change of date if the contacts 75 are arranged to close at mid-night. Manuallyoperated switches 65, 66 are provided for test purposes through which the record surface may be made to move continuously or for a single step preceded by a time record.