EP0462888B1 - Programmer with timing cam - Google Patents

Description

The present invention relates to a programmer for an apparatus, or system, provided with a plurality of electrical members to be fed selectively and sequentially, a programmer comprising a plurality of cams cooperating with a plurality of contacts for supplying said members, and means for driving said cams in movement.

Such a programmer is used in particular in the household appliance field, for devices such as washing machines for washing clothes or dishes, for example.

More specifically, the present invention relates to programmers intended to operate in combination with a timing device, or timer.

The addition of a timer to a programmer makes it possible to introduce a time delay before, during, or after the progress of the program controlled by the movement of the cams.

A time delay before the program runs allows the start time of the program to be controlled in advance. A time delay during the course of the program allows for example, in the case of a washing machine, to soak the laundry in the machine at rest, for a period of time, between the prewash and the actual washing. A time delay after the program has run is useful in machines that dry laundry after washing, to control the duration of drying.

Most often, in a machine where a programmer is intended to operate in combination with a timer, there is a programmer and a timer each provided with its own drive motor, the timer being controlled by means of an electrical contact actuated by a cam of the programmer. This solution is of relatively high cost and volume.

To partially avoid these drawbacks, French patent N. 1,595,564 proposes a programmer provided with a timing cam driven, by means of a reduction gear, by the motor which already drives the moving cams. This adjustable time delay makes it possible to inhibit for a certain time a mechanical device, arranged between the engine and a block of cams, to transform the continuous movement of the engine into a stepping movement of the block of cams. The timing cam thus makes it possible to delay a certain number of steps during the course of the program.

However, this known device is quite complex and bulky, and requires the use of a reduction gear comprising numerous pulleys, if one wishes to be able to set the timing to a high value, for example several hours. In this case, the setting accuracy of the short delay times is poor.

The present invention aims to overcome the above drawbacks.

To this end, it relates to a programmer for an apparatus, or system, provided with a plurality of electrical members to be fed selectively and sequentially, a programmer comprising, on the one hand, a plurality of cams cooperating with a plurality of contacts d of said organs, and of the means for driving said moving cams and, on the other hand, at least one timing cam driven, by means of a reduction gear, by said drive means, programmer characterized in that said reduction gear comprises a first wheel driven in continuous rotation and provided with a pawl, a second wheel comprising said timing cam and provided with toothing, the pawl being able to assume a rest position in which it does not cooperate with the toothing and a working position in which it cooperates with the teeth, and a fixed cam whose profile controls the passage of said pawl from the rest position to the working position and vice versa.

Advantageously, means are provided for inhibiting the passage of said pawl in the working position, controlled by a cam of said plurality of cams.

Advantageously also, there is provided, between said drive means and said plurality of cams, a device similar to said reduction device.

The present invention will be better understood on reading the following description of the preferred embodiment of the programmer of the invention, made with reference to the accompanying drawings in which the single figure shows an exploded perspective view of this programmer.

The programmer which will now be described is more particularly intended for a washing machine and dryer.

With reference to the figure, an electric motor 1, here a synchronous motor, drives, by means of a reduction gear 2, here a gear train, a block 5 of fast cams, rotating around an axis 16.

The block 5 comprises on the one hand reversing cams, of which only one 51 is shown in the figure for the sake of simplicity, and on the other hand a wheel 52. The wheel 52 is provided with a pawl 3 movable around an axis parallel to axis 16.

In known manner, the reversing cams cooperate with contacts not shown to control the periodic change of the direction of rotation of the machine drum.

The pawl 3 is returned by a spring so that its active part, in this case its pointed end 31, moves away from the axis 16. It is however limited in this movement by a lever 4, movable around an axis integral with the wheel 52 and parallel to the axis 16. When the programmer is assembled, the lever 4 comes to cooperate with the internal profile 61 of a fixed cam 6. Here the internal profile 61 of the cam 6 is circular, except in a small area where it has an accident 15 which here consists of a recess 15 whose radius is greater than that of the circular part of the inner profile 61. Thus, when the lever 4 cooperates with the circular part of the profile 61, it maintains the pawl 3 in a first position where its active part is relatively close to the axis 16, while when it cooperates with the accident 15, it allows the active part of the pawl 3 to pass into a second position, more away from axis 16.

A block 7 of slow cams is provided with an inwardly facing toothing, not visible in the figure, of a diameter such that the pawl 3 does not cooperate with this toothing when it is in the first position, or rest position, while it cooperates with it when it is in the second position, or working position.

Each of the cams of block 7 controls, in principle, one of the components of the machine, such as the pump, the heating resistor, and so on, by cooperating with contacts not shown.

A toothed pinion 9 cooperates with an external toothing of the wheel 52. The pinion 9 is integral in rotation with a shaft 10, parallel to the axis 16. The shaft 10 is itself integral with another toothed pinion 9 ′, Here identical to the pinion 9.

The pinion 9 ′ drives a wheel 52 ′ provided with an external toothing. The wheel 52 ′ is here identical to the wheel 52. Thus it comprises a pawl 3 ′ and a lever 4 ′ identical to the pawl 3 and to the lever 4, respectively.

A fixed cam 6 ′, identical to the fixed cam 6, that is to say having an internal profile 61 ′ and an accident 15 ′, cooperates with the lever 4 ′.

A block of cams 11 has a toothing turned inwards identical to that of block 7, toothing also not visible in the figure, in order to cooperate with the lever 4 ′.

The wheel 52 ′ and the block 11 are movable in rotation around a shaft 12 integral with the cam block 7. The shaft 12 is provided with a control button 17 which allows, as will be better understood below, select a specific washing program by adjusting the initial position of block 7.

The block 11 here comprises a cam 111 whose profile acts on an electrical contact, not shown, which controls the drying system of the machine. The cam 111 is here integral with a toothed wheel 112 whose initial position is adjusted manually by means of return wheels 13 and a control button 14.

Here, there is provided, on the fixed cam 6 ′, a finger 62 which can occupy two positions, one in which it closes the recess, or accident 15 ′, the other in which it releases it.

The finger 62 is integral with a shaft 63 parallel to the axis 16, and provided with a lever 64 which reads the profile of a cam 71 of the block 7.

The programmer which has just been described operates as will now be explained.

First of all, before the actual start-up of the machine, its user selects a particular program, from among all of the available programs, using the control button 17. Similarly, he controls the drying time. laundry using button 14.

Then, as soon as the machine is powered up, the motor 1 is supplied and runs continuously. The motor 1 thus drives in continuous rotation on the one hand the block 5 and therefore the wheel 52, and on the other hand, via the toothed wheels 9 and 9 ′ and the shaft 10, the wheel 52 ′.

As long as the lever 4 cooperates with the circular part of the profile 61 of the fixed cam 6, the pawl 3 is in the rest position, it does not cooperate with the teeth inside of the cam block 7, and the latter remains stationary. As soon as the lever 4 encounters the accident 15, it lets the pawl 3 pass into the working position where it cooperates with the teeth of the block 7, which causes the drive of this block over an angle substantially equal to that under which is given the accident 15 from axis 16, corresponding to a step in the program. Thus, thanks to the pawl 3, to the lever 4 and to the accident 15, the wheel 52, driven in continuous rotation by the motor 1, drives the cam block 7 to make it run through a program step each time the lever 4 passes in front of the accident 15. Thus, the cam block 7 advances by one program step at each revolution of the wheel 52. The device comprising the wheel 52, the pawl 3, the lever 4, the cam 6 and the toothing 7, known as a "pulse device" or "step by step drive device", is described in particular in French patent N 1,533,219 and its first addition, as well as in the French patent already cited N . 1,595,564.

Here, the progress of the program is controlled by the stepwise movements of the cam block 7, while the reversing cams such as the cam 51 permanently control the invention of the direction of rotation of the motor which drives the drum.

The cam 71 has here a profile such that during the progress of the program by moving step by step of the block 7, the finger 62 closes the accident 15 ′. As a result, despite the continuous rotation of the wheel 52 ′, the block 111 remains stationary. Indeed, and in a known manner, everything happens as if the accident 15 ′ did not exist, and the pawl 3 ′ never cooperates with the teeth of block 11. A cam of block 7 controls the opening, during program sequence, of a switch arranged in series in the circuit of the drying system, which then remains at rest.

When the washing program comes to an end, block 7 comes to a standstill, for example because a tooth from its internal toothing is omitted, or by any other known means. Simultaneously, the cam of the block 7 which controls the drying system controls the closing of the switch so that drying begins, and the cam 71 controls the release of the accident 15 ′, which amounts to causing the starting of the timer.

Indeed, the stepping drive device comprising the wheel 52 ′, the pawl 3 ′, the lever 4 ′, the fixed cam 15 ′ and the teeth of the block 11 act in the manner of a reduction gear since, at each turn of the wheel 52 ′, the block 11 turns only by a reduced angle, here and for example the same as that which corresponds to a program step, corresponding for example to an angle of 6 degrees. The reduction ratio introduced by the stepping drive device is therefore 60. It would take at least three pulleys to obtain such a reduction ratio with a gear reducer of the reducer type 2. Here, on the contrary, we obtain such a relationship with a reliable and safe device, which has proven itself, and strictly identical to the stepping drive device used in the programmer itself, that is to say the one comprising the wheel 52, the pawl 3, the lever 4, the fixed cam 6 and the teeth of the block 7.

Drying continues for a period of time set with the button 14, until the cam 111 opens a switch arranged in series in the supply circuit of the drying system.

The washing + drying cycle is then finished.

It should be noted that the programmer of the invention, provided with its integrated timer, practically only implements parts already used in the known programmer. This is a factor that reduces manufacturing and maintenance costs. In addition, the timer itself occupies a small volume, due to the unusual use which is made of the known device for stepping.

Naturally, the present invention is not limited to the description which has just been made.

Thus the block of cams 11 could be used to introduce a delay of one or more functions of the program controlled by the block 7, by means of a device of the type of that of the finger 62, which would seal the accident 15 by response to the reading of the profile of a cam of block 11 by a lever similar to lever 64. Block 11 could also be used like that of a second independent programmer of block 7.

Similarly, it is possible to provide, on the step-by-step devices, several accidents such as accidents 15 and 15 ′, distributed around the fixed cams 6 and 6 ′, respectively, and which can be closed by movable fingers to vary the movement of blocks 7 and 11, respectively.

In a known manner, the levers 4 and 4 ′ allow amplification, for the pawls 3 and 3 ′, respectively, of the displacement which would be caused by the accident 15. They are not however compulsory, in which case each accident acts directly on the corresponding pawl.

The adjuster 14 for the duration of the delay introduced by the timer could be integral with a shaft concentric with the shaft 12 instead of being off-center as in the drawings.

Finally, if the programmer of the invention is particularly suitable for washing machines or dishes, it can also be used for any system comprising a plurality of members to be fed selectively and sequentially.

Claims (3)

1. Programmer for an appliance, or system, provided with a plurality of electrical members to be supplied with power selectively and sequentially, a programmer comprising, on the one hand, a plurality of cams (7) cooperating with a plurality of contacts for the supply of power to said members, and drive means (1, 2) for setting said cams (7) in movement and, on the other hand, at least one delay cam (111) driven, through the intermediary of reduction gearing (3′, 4′, 6′, 11), by said drive means (1, 2), programmer characterised by the fact that said reduction gearing comprises a first wheel (52′) set in continuous rotation and provided with a ratchet (3′), a second wheel (11) comprising said delay cam and provided with toothing, the ratchet (3′) being able to assume an inoperative position in which it does not cooperate with the toothing and a working position in which it cooperates with the toothing, and a fixed cam (6′) whereof the profile (61′) controls the passage of said ratchet (3′) from the inoperative position to the working position and vice versa.
2. Programmer according to Claim 1, in which means (62-64) are provided for inhibiting the passage of said ratchet (3′) into the working position, which means are controlled by a cam of said plurality (7) of cams.
3. Programmer according to one of Claims 1 or 2, in which a device (52, 3, 4, 6) similar to said speed-reducing device (52′, 3′, 4′, 6′) is provided, between said drive means (1, 2) and said plurality of cams (7).

Images