US3602050A

US3602050A - Programmers for electric household appliances

Info

Publication number: US3602050A
Application number: US840414A
Authority: US
Inventors: Jean Jullien-Davin
Original assignee: Crouzet SA
Current assignee: Thales Avionics SAS
Priority date: 1968-07-15
Filing date: 1969-07-09
Publication date: 1971-08-31
Anticipated expiration: 1988-08-31
Also published as: DE1935261A1; GB1279143A; FR1583273A

Abstract

Programmer for electric household washing machines, of the type comprising electromagnetic means for interrupting the step-bystep forward rotary motion of the cam unit throughout the duration of predetermined operations of the control cycle of the machine and means for restoring said forward rotary motion after a period of time which may be varied, which comprises an adjustable auxiliary timer which actuates a switching element on expiration of the selected time interval so as to cause resumption of the step-by-step motion, the time base of said auxiliary timer being constituted by the motor means for driving the programmer at a constant speed.

Description

U nited. States Patent Jean Jullien-Davin inventor I Valence, France Appl. No. 840,414 Filed July 9, 1969 Patented Aug. 31, 1911 Assignee Crouzet Paris, France Priority France PROGRAMMERS FOR ELECTRIC HOUSEHOLD APPLIANCES 3 Claims, 4 Drawing Figs.

[13. Cl 74/35, v 200/38 A lnt.Cl 005; 21/00 lleld oi Search ..74/3.52.3.5,

References Cited a UNITED STATES PATENTS 3,180,157 4/1965 Harris Primary ExaminerMilton Kaufman Attameyl-iolman and Stern ABS'lRACTi Programmer for electric household washing.

machines, of the type comprising electromagnetic means for interrupting the step-by-step forward rotary motion of the cam unit throughout the duration of predetermined operations of the control cycle of the machine and means for restoring said forward rotary motion after a period of time which may be varied, which comprises an adjustable auxiliary timer which actuates a switching element on expiration of the selected time interval so as to cause resumption of the step-by-step motion, the time base of said auxiliary timer being constituted by the motor means for driving the programmer at a constant speed.

PIOGRAMMERS FOR ELECTRIC HOUSEHOLD APPLIANCES This invention is directed to improvements to programmers for electric household appliances such as washing machines so as to permit the interruption of a program for any length of time which may be either fixed or variable.

The aim of these improvements is to permit the rational use of new enzyme detergents in accordance with a control cycle in which the washing machine and consequently the programmer are intended to remain motionless over a period of several hours.

As is in fact already known, provision is made in many types of programmers for an electromagnetic device referred to as a m9 2i "-.th. sissisn un of which s t in mtp h step-by-step forward rotary motion of the cam unit during certain operations such as heating, filling or emptying until completion of such operations, whereupon an ancillary unit such as a thermostat or a pressostat causes the resumption of the step-by-step motion (by virtue of a change of state of a switching or contact-breaking element).

In order to permit the interruption of the step-by-step pulses over a long period of time which may be either fixed or variable. this invention which makes use of the known thermostop device for the purpose of stopping said pulses is characterized in that pulse resumption is carried out as a result of a selection produced by an adjustable auxiliary timer which comprises a switching (or contact-breaking) element whose change of state initiates said pulse resumption on expiration of the set time interval or period of interruption of step-by-step pulses (but not in dependence on a selecting cam and by means of a thermostat or a pressostat as is the case in some known methods).

The auxiliary timer referred to above is advantageously integrated with the programmer and its time base is constituted by the synchronous reduction-gear motor which drives the programmer.

The programmer according to the invention as equipped with the aforesaid auxiliary timer comprises a time wheel having a peripheral set of teeth and adapted to rotate through an angle which is proportional to the time interval, a driving lug which is integral with a moving system actuated by the synchronous reduction-gear motor for driving the time wheel periodically in a one-step movement corresponding to one tooth, an adjustable stop for fixing the origin of the angle which is proportional to the time interval, a catch which is rigidly fixed to the time wheel for cooperating with said adjustable stop, a restoring spring for returning the time wheel against the adjustable stop and a retaining pawl which is adapted to cooperate with the set of teeth of the time wheel so as to prevent said wheel from being returned to zero. The programmer is characterized in that, on the one hand, the catch of the time wheel of the auxiliary timer has a portion forming a cam in order to actuate a switching or contact-breaking element on expiration of the time interval or period of interruption of the step-by-step pulses and the change of state of said element then restores the step-b'y-step pulses when said switching element has been selected by a cam at the moment when the thermostop or pulse-stopping device has been put into service. Said programmer is further characterized in that, on the other hand, the time wheel is provided at its periphery with a nontoothed zone which is intended to cooperate with the retaining pawl at a point beyond the tooth which corresponds to the expiration of the time interval in order to ensure that the time wheel returns to the same position after each periodic drive motion and that the rotation of said wheel does not continue beyond the set time interval if this interval is shorter than the time of heating or filling and if the thermostop has been put into service for such an operation (or in other words if the switching element selected is that of the thermostat or of the pressostat).

In accordance with a further property of the programmer in accordance with the invention, the thermostop which serves to interrupt the step-by-step forward motion of the programmer cams is constituted by a lug which is integral with the moving armature and adapted to cooperate with an arm of the retaining pawl in order to prevent the action of said retaining pawl of the time wheel when it is in the particular state (operative or inoperative) which permits step-by-step forward motion of the cams and in order to permit the action of said pawl when it is in the other state (inoperative or operative) in which the step-by-step forward motion of the cams is impossible.

The properties referred to above will be clearly brought out in the following detail description. reference being made to the accompanying drawings which illustrate one nonlimitative example of the invention. and in which:

FIG. I is a diagrammatic presentation of a known step-bystep drive system equipped with an electromagnetic device for stopping the step-by-step pulses when said system is in the inoperative state;

FIG. 2 is a corresponding electric circuit diagram in which the timer, thermostat and pressostat have normally open contacts which close in order to cause the resumption of pulses;

FIG. 3 corresponds to FIG. I in the case in which the inoperative position of the system for stopping the step-by-step pulses in the position which corresponds to step-by-step forward rotary motion;

FIG. 4 is the corresponding diagram in which the ancillaries are of the normally closed circuit type.

There is shown in FIG. I for the sake of reference a known device for driving the cams of a programmer in step-by-step forward rotary motion. A spiral cam I driven by a synchronous reduction-gear motor which is not shown in the drawings produces once per revolution the oscillating motion of a lever 2 and a pawl 3 which, under the action of a spring 4, displaces by one step in the rotary direction a ratchet-wheel 5 which is keyed on the camshaft 6.

A system of pinions 789-I0 couples the spiral cam I to a rotary driving lug II which is adapted to cooperate once per revolution with the set of teeth of a time wheel 12; said time wheel is rotationally urged by a spring 13 against an adjustable stop 14a provided on a toothed wheel 14 and this latter is coupled to a control knob I5 by means of toothed wheels 14'. 14''; the complete assembly is maintained in the preset position by means of a leaf spring I6. A catch 12a which is intended to cooperate with the stop 14a performs the function of a cam for the purpose of displacing a movable contact strip 17 which cooperates with a stationary contact I7 Drive means, such as a synchronous motor 70, provided for continuously rotating the spiral cam l and the

pinions

7, 8, 9 and 10.

A retaining pawl 18 which is acted upon by a spring 19 is adapted to cooperate with the set of teeth of the time wheel 12 so that the catch 12a may thus be prevented from returning to its starting point against the adjustable stop 14a under the action of the spring 13.

The moving armature 20 of an electromagnet 21 is controlled by the action of a spring 22 so that, when the coil of the electromagnet 21 is not energized, the armature comes into the position shown in the drawings in which the pawl 3 is prevented from engaging with the teeth of the ratchet-wheel 5, thereby stopping the step-by-step rotary motion of the camshaft 6. The assembly 20-21-22 thus constitutes the known device which is referred to as a thermostop."

As is apparent from FIG. 2, when one of the cams which is keyed on the shaft 6, namely the cam 60, opens the circuit 210 of the coil 21 in a position in which one of the cams 6b or 60 each of which is shown as having a single raised lobe; closes a

contact

21b or 21c so as to put into service an auxiliary device (thermostat 23 or pressostat 24) having normally open contacts, the step-by-step progression remains uninterrupted until heating, filling or emptying is completed, whereupon the

respective contact

23 or 24 closes under the influence of the raised lobe. activates the coil 21, and produces a first singlestep rotary movement which restores the step-by-step cycle by reclosing the contact 21a.

The structure of the invention, as well as a portion of its operation, should now be clearly understood. An additional feature of its operation is as follows:

When the cam 6a opens the contact 21a and thus cuts off the supply of current to the coil 21, a cam 6d which closes the contact 21d connects the coil 21 in series with the open contact elements l7, 17. Under these conditions, the step-by-step pulses are interrupted until termination of the set time interval, whereupon the contact l7, 17' is closed and energizes the coil 21. The armature 20 then moves in the direction of the time arrow and permits the pawl 3 to engage with the teeth of the ratchet-wheel 5. Consequently, when the cam follower drops back into the falloff portion of the rotating cam 1 under the action of a spring 4, the ratchet-wheel will rotate by one step.

At the same time, in the new position in which the coil 21 is energized, the armature is caused by means of a lug 20a which cooperates with an arm 18a of the pawl 18 to maintain this latter out of contact with the teeth of the time wheel 12. Consequently, when the lug 11 which has completed the rotary motion is no longer engaged with the time wheel 12, said time wheel is free to return to its starting point under the action of the restoring spring 13. As long as the step-by-step pul' ses are not again interrupted, the time wheel 12 advances by one tooth per revolution of the lug 11 and then returns to its starting point since it is no longer retained by. the pawl 18.

The time during which the pulses are interrupted is usually set for a long period (several hours) in order to permit the so-. called biological washing with enzyme detergents. The time setting does not present any special problem providing that the time chosen is longer than the times of heating, filling,

emptying and the like. However, should it be found necessary for any reason to set the pulse-interruption time at a value which is shorter than the normal time required for any one of the above-mentioned operations (for example the heating time), the time wheel 12 would thus reach the end of its travel before the step-by-step pulses are restored; said wheel would then be driven beyond its intended travel, with the result that the restoring spring 13 would be caused to carry out more than one revolution on the hub of the wheel 12.

In order to limit the travel of the time wheel 12 to a position trated in FIG. 4 and which is slightly more simple than that of FIG. 2 since the selection cam 6a is no longer necessary. The

first of the

cams

6b, 6c, 6d which closes its

contact

21b, 21c or 7 21d interrupts the step-by-step pulses until the normally closed

contacts

23, 24 or 17,17 are opened.

Except for this difference, the operation of this alternative form is otherwise identical with that previously described, and will not be again described in detail.

What I claim is:

l. A programmer for electric household washing machines,

to said cam unit and thereby permitting said step-by-step forward rotary motion after a period of time which may be varied, which comprises an adjustable auxiliary timer which actuates a switching element on expiration of the selected time interval so as to cause said reconnection of said drive means to said cam unit and resumption of the step-by-step motion, the time base of said auxiliary timer being constituted by a motor means for driving the programmer at a constant speed.

2. A programmer in accordance with claim 1 wherein said auxiliary timer comprises a time wheel having a peripheral set 5 of teeth and adapted to rotate through an angle which is proportional to the selected time interval, a driving lug which is integral with a moving system actuated by the motor means for driving the time wheel in a onestep movement corresponding to one of said teeth, an adjustable stop for fixing the origin of the angle which is proportional to the selected time interval and defining a zero position, a catch which is rigidly fixed to the time wheel for cooperating with said adjustable stop, a restoring spring for returning the time wheel against the adjustable stop, and a retaining pawl which is adapted to cooperate with the set of teeth of the time wheel so as to selectively prevent said wheel from being returned to its zero position, characterized in that on the one hand the catch of the time wheel of the auxiliary timer has a portion forming a in which the contact l7, 17' has been actuated, the periphery of the time wheel includes a neutral portion 12b, or in other words a portion which is not provided with teeth.

Under these conditions, when the contact l7, 17 has been actuated, the retaining pawl 18 engages in the last tooth 12c before the neutral portion 12b,- any further thrust exerted by the lug 11 will cause the wheel l2 to advance temporarily by one step; but when said lug ll finally moves away from the wheel 12, this latter will then move back until the pawl 18 falls again into the last tooth 12c and this will continue until the particular ancillary unit 23 or 24 (thermostat or pressostat) which is selected by a

cam

6b or 6c has completed its action, whereupon the coil 2l is energized, the step-by-step pulses are resumed and the wheel 12 returns to zero. in this manner, it will be understood that the ancillary unit essentially overrides the operation of the time wheel in this case.

FIG. 3 which is similar to FIG. 1 corresponds to the case in which the thermostop 20-21-22 is of the type in which the step-by-step pulses are interrupted by the armature 20 in the operative position, that is to say when the coil 21 is energized. The contact l7, 17' is then normally closed and opens at the end of the set time interval in order that the step-by-step pulses may again take place.'Similarly, thethermostat 23 and pressostat 24 are of the normally closed contact type.

This alternative form results in the diagram which is illuscam adapted to engage and actuate a switching element on expiration of a time of interruption of the step-by-step rotary motion and the actuation of said switching element then permits the step-by-step pulses when said switching element has been selected .by said cam at the moment when the electromagnetic. means for stopping the step-by-step motion pulses has been activated by said switching element and that, on the other hand, the time wheel is provided at its periphery with a nontoothed zone for cooperating with the retaining pawl at a point beyond the tooth which corresponds to the expiration of t which is integral with said moving armature and adapted to cooperate with an arm of the retaining pawl to disengage said retaining pawl from the time wheel when said electromagnetic device is activated to permit the step-by-step forward motion of the cams, and'to engage said pawl with said time wheel when said electromagnetic device is deactivated to prevent the step-by-step forward motion of the cams.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent 7 3602050 Dated August 31, 1971 eg; JEAN JULLIEN-DAVIN It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On the Abstract page, item [32] Priority, insert July 15, 1968 Signed and sealed this 11 th day of July 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Atte sting Officer Commissioner of Patents )RM PO-1050 (10-69) USCQMM'DC 60375-P69 i lLSv GOVERNMENT PRINTING OFFICEJ l9! 0-356-3 4

Claims

1. A programmer for electric household washing machines, of the type comprising a cam unit controlling operation of the machine, drive means to rotate the cam unit in a forward rotary step-bystep manner, electromagnetic means for disconnecting said drive means from said cam unit to interrupt the step-by-step forward rotary motion of the cam unit throughout the duration of predetermined operations of the control cycle of the machine, and means for reconnecting said drive means to said cam unit and thereby permitting said step-by-step forward rotary motion after a period of time which may be varied, which comprises an adjustable auxiliary timer which actuates a switching element on expiration of the selected time interval so as to cause said reconnection of said drive means to said cam unit and resumption of the step-by-step motion, the time base of said auxiliary timer being constituted by a motor means for driving the programmer at a constant speed.

2. A programmer in accordance with claim 1 wherein said auxiliary timer comprises a time wheel having a peripheral set of teeth and adapted to rotate through an angle which is proportional to the selected time interval, a driving lug which is integral with a moving system actuated by the motor means for driving the time wheel in a one-step movement corresponding to one of said teeth, an adjustable stop for fixing the origin of the angle which is proportional to the selected time interval and defining a zero position, a catch which is rigidly fixed to the time wheel for cooperating with said adjustable stop, a restoring spring for returning the time wheel against the adjustable stop, and a retaining pawl which is adapted to cooperate with the set of teeth of the time wheel so as to selectively prevent said wheel from being returned to its zero position, characterized in that on the one hand the catch of the time wheel of the auxiliary timer has a portion forming a cam adapted to engage and actuate a switching element on expiration of a time of interruption of the step-by-step rotary motion and the actuation of said swiTching element then permits the step-by-step pulses when said switching element has been selected by said cam at the moment when the electromagnetic means for stopping the step-by-step motion pulses has been activated by said switching element and that, on the other hand, the time wheel is provided at its periphery with a nontoothed zone for cooperating with the retaining pawl at a point beyond the tooth which corresponds to the expiration of the time interval in order to ensure that the time wheel returns to the same position after each stepwise rotational motion and that the rotation of said wheel does not continue beyond the set time interval if this interval is shorter than the time of heating or filling.

3. A programmer in accordance with claim 2, wherein the electromagnetic device comprises a moving armature, a lug which is integral with said moving armature and adapted to cooperate with an arm of the retaining pawl to disengage said retaining pawl from the time wheel when said electromagnetic device is activated to permit the step-by-step forward motion of the cams, and to engage said pawl with said time wheel when said electromagnetic device is deactivated to prevent the step-by-step forward motion of the cams.