Patent GB-1463996-A (GB)
Title: Programmer
IPC: G05B19/06
Filed: 1974-12-12
Abstract: 1463996 Programmer for washing machine ETABS CARPANO & PONS 12 Dec 1974 [27 Dec 1973] 53718/74 Heading DIA [Also in Division F2]  A stepping drive for a programer cam 1 of a clothes or dish washer, provided with means for interrupting the stepping for pre selected periods before or during the cycle, comprises a gear wheel 6, continuously motor driven, and having a crank pin 7 engaging parts 11, 12 of a pawl-carrying lever 9 to oscillate it positively in both directions, a spring-loaded drive pawl 13, pivoted on the lever 9, engaging teeth of a ratchet wheel 17 housing also gear teeth 18 continuously meshing teeth on the program cam 1, whereby, in absence of delay control, the ratchet 17 and cam 1 are stepped forward (clockwise the ratchet counterclockwise the cam) at each forward (clockwise) oscillation of the lever 9 and retained by a spring-loaded back-stop pawl 25 for the return oscillation, the selector control for lifting the drive pawl 13 away from the ratchet 17 to provide interruption being as follows. The drive pawl 13 is lifted by a ramp 47 on a pawl-lift member 42 when the latter is turned clockwise by an arm 41 of the member engaging any one of three upper levels 35, 36 or 37 of a cam 31 coaxial with the input wheel 6 and integral with a ratchet 50 having three groups 55, 56, 57 of notches of different levels, corresponding with the cam levels, and engaged by a beak 68 on a selector lever 65, pivoted at 66 and having at its other end a beak 67 engageable with three corresponding different levels 61, 62, 63 of a notch in a part 59 of the program cam 1. During each forward (counterclockwise) rotation of the input wheel 6 the cam 31 and ratchet 50 are turned through a fraction n of a revolution in the same direction by a sheave 29, prevented from rotation by pin 24 engaging a stationary slot 32, mounted on an eccentric boss 28 of the input wheel 6, and having three teeth engaging internal teeth in the cam 31 during the drive fraction n, at the end of which the teeth disengage, and, providing the cam 31 is not detained by engagement of the beak 68 in one of the notches 55 &c of the ratchet 50, a torsion spring 71 returns the cam 31 clockwise through the same fraction n against a stop (not shown). Normal operation. The beak 67 of the selector lever 65 lies on the periphery 60 of the selector part 59 of the program cam 1, thereby lifting the beak 68 away from the ratchet 50 which, with the cam 31, is then turned forwards and backwards without interruption. In the start position, Fig. 1, the pawl lift arm 41 lies in a notch 38 of the cam 31 freeing the pawl 13 for stepping action, which takes place during the return movement of the cam 31 at which time the lift arm 41 occupies the notch 38, it being on the lift level during the forward movement of the cam 31. Delay operation. If the stepping is to be delayed to the greatest of three selectable intervals, the program cam 1 is manually turned so that the beak 67 of the selector lever 65 is loaded by a spring 69 into the deepest 63 of the notches 61, 62, 63 provided in the part 59 of the cam 1, in which position the beak 68 of the lever 65 is able to penetrate the notches of all three level groups 55, 56, 57 in the ratchet 17. The latter 17 is thereby prevented from making its spring return movement to free the drive pawl 13, but can still be stepped forward by the eccentric 28, through increments n during which the beak 68 rides into successive notches 55 &c of all the groups, and the pawl-lift arm 41 rides on the upper three levels 35, 36, 37 of the cam 31, which is not arrested when passing over intervening lower levels 39, 40. When the beak 68 reaches the final notch 57d, the pawl-lift arm 41 rides off the cam level 35 into the succeeding notch 38, thereby freeing the drive pawl 13 to commence stepping. During the subsequent step the back-stop pawl 25 presses down the selector lever 65 through a pin 76, lifting the beak 68 away from the ratchet 50, permitting the spring 71 to return the ratchet 50 and cam 31 to the start position, Figs. 1, and off for normal uninterrupted stepping to continue. Intermediate delays. Turning the part 59 of the program cam 1 until the beak 67 lies on the intermediate level 62 prevents the beak 67 from engaging in the deepest notch group 57 of the ratchet 50, so that the delay is terminated at the last notch 56f of the second group 56; whilst turning the highest level 61 under the beak 67 similarly eliminates also the intermediate depth group 56, so that delay is terminated at the last notch 55d of the shallowest notch group 55.