Patent GB-686841-A (GB)
Title: A combined electrically driven date-indicator and clock
IPC: G04C17/00
Filed: 1950-01-24
Abstract: 686,841. Control of several motors. HAAB, O. Jan. 24, 1950, No. 1899/50. Class 38 (iii) [Also in Group XIX] A combination of a clock and an electrically operated date indicator comprises an electric circuit including a clock-driven device for controlling a plurality of electric motors adapted to drive a day-name drum, a units digit drum, provided with transfer mechanism to a tens digit drum, and a month-name drum, provided with means for controlling the operation of the units and tens drum in accordance with the length of the month and means in the circuit for adjusting the control device for either a leap year or a normal year, the clock and indicator being housed in a common casing with apertures for displaying the time, day, date and month. Motors 5, 6,7, Fig. 6, advance day-name drum 1, units drum 3 and month drum 4 respectively when circuits therethrough, including a source of current z are completed through contacts r, s and g or h and stop when the circuits are broken through devices controlled by pins 21, Fig. 2 and slots g' and h<SP>I</SP> respectively. About midnight a 24 hour wheel 10 causes a star wheel 14 to close the contacts s which starts motor 6 and advances drum 3 causing a roller 60 to fall off a pin 21 and through arm 20 to lock the contact s with a spring 22a and through arm 87<SP>I</SP> pivots a pawl 61 to move the star wheel free from the contact so that, after 1/10th of a revolution of drum 3, when the roller 60 rides up on the next pin 21, the contact s opens. Soon afterwards the drum 1 is advanced 1/14th of a revolution by similar means. While the drum 3 passes from 9 to 0 a roller 52 pushes inwards a pin 25 against return springs 70 bearing on pins 94 disposed near the bevelled ends of an arcuate head 25<SP>I</SP>, Fig. 5, of the pin 25, which then penetrates a resilient ring 27 in the end of drum 2 and carries it forward one digit, against a return spring 30, Fig. 4, attached by string to its hub, whilst moving a stop 29 carried by a .spring 45 out of register with a disc 28 fixed to the drum 2. During each month one contact a + b, c or d, is closed by one of twelve pins 38 arranged in three corresponding rows according to whether they are to operate in February, a thirty day month or a thirty-one day month and in sequence round an extension of the drum 4 appropriate to the order of the months of the year, while during the twenty's and thirty's of each month contacts a + b and c + d respectively, are closed by pins 41 a + b, 41 c + d, on the tens drum 2 and lastly, while the units drum registers 8, 9, 0 and 1 contacts a, b, c and d are closed respectively, by pins 40a, 40c and 40d and according to whether it is a leap year or a normal year a contact / or m is selected by a manual switch 42. Thus according to the length of the month the appropriate combination of contacts, controlled by pins 38, 41 and 40 and in February by the switch 42, closes at the end of the last day of the month and completes a circuit through an electromagnet 32 whose armature performs three functions:- (1) through a string 44 it releases the stop 29 from the disc 28, locking spring 46 holding it free, and allows spring 30 to return drum 2 to zero position where it is arrested by stop 47; (a) breaking the circuit to de-energise the electromagnet 32; (b) closing contacts o, p; (c) through pin 48 releasing the locking spring 46 to allow the pin 29 to re-register with the disc 28 and through pin 48 and spring 49 closing contact n so that a circuit through contacts n, p and motor 6 is closed and units drum 3 is advanced till in the unit position an arm 51 moving therewith engages a spring 50 to open the contact n; (2) through a string 33 causes a roller freely mounted m a fork 52 on a shaft 52a to move out of the path of the pin head 25<SP>I</SP> where it is held by a pawl 53 to inhibit tens transfer during rotation of the drum 3 being released when a pin 55 rocks a roller 54 to release the pawl 53; (3) also through string 33 changes the position of a two-way switch 35a so that current passes through contact 31g or 31h, alternating month by month, and motor 7 which drives the month drum 4 until a slotted disc moving therewith opens the contact by presenting a slot g<SP>I</SP> or hI. To set the calendar to any date, a rim 107 is provided on the month drum 4 for manipulation, a manual switch in a circuit through motor 5 serves for adjusting the drum 1.