GB2266188A

GB2266188A - A control device, more particularly for electrical domestic appliances

Info

Publication number: GB2266188A
Application number: GB9307544A
Authority: GB
Inventors: Michele Farano
Original assignee: Elbi International SpA
Current assignee: Elbi International SpA
Priority date: 1992-04-14
Filing date: 1993-04-13
Publication date: 1993-10-20
Also published as: GB9307544D0; ITTO920336A1; ITTO920336A0; DE9305556U1; IT1259540B

Abstract

A control device for electrical domestic appliances such as washing machines comprises a support casing (1) securable in an aperture (2) in a wall (3) of the machine, a number of push-button control means (A-N) movable between on and off positions, mechanical retaining means (8) for retaining one or more push button control means in respective on positions, and an electrically controlled actuator (20) coupled to the mechanical retaining means (8) associated with one of the push-button means (A) adapted to remain in the on position when the domestic electrical appliance is in operation. Such one push button means (A) serves as a reference push-button and the actuator (20) returns it to the off position if a fault or breakdown occurs during operation of the electrical appliance. The reference push button control may operate an electric switch. <IMAGE>

Description

DESCRIPTION The invention relates to a control device for use in domestic electrical appliances, more specifically a control panel particularly for a washing machine, comprising a support structure for securing in an aperture in a wall of the machine, a number of pushbutton control means mounted for movement in the structure and adapted to take up a switched-on position and a switched-off position, and mechanical retaining means borne by the structure and adapted, during operation of the machine, to retain one or more pushbutton control means in respective switched-on positions.

The aim of the invention is to provide a control device comprising a control panel of the specified kind, for use in a domestic electrical appliance provided with sensor means adapted to supply an electric control signal in the event of a fault or breakdown.

More particularly the aim of the invention is to provide a control device comprising a control panel and adapted, via a push-button control means, to provide a visual signal in the event of a fault or breakdown in the machine.

According to the invention, this aim is achieved by means of a control device comprising a control panel of the specified kind, characterised in that the device is associated with an electrically controlled actuator including a control element coupled in operation to the mechanical retaining means associated with a reference push-button control means adapted during operation of the machine to remain in the switched-on position so as automatically, during operation of the machine, to move the reference push-button means to the switched-off position when a control signal is applied to the actuator.

In a first embodiment, the reference push-button means advantageously comprises the principal push-button control means of the control panel which, when switched on, normally closes an electric switch for connecting the washing machine to a voltage supply, usually the electric mains.

In another embodiment, the reference push-button control means comprises a supplementary push-button means which is not associated with any normal operative function specific to the machine, but operates only as a signalling push-button.

Other features and advantages of the invention will be clear from the following detailed description with reference to the accompanying drawings, given by way of non-limitative example only, in which: Fig. 1 is a diagrammatic view, partly in section, of a first embodiment of a control panel according to the invention; Figs. 2 to 4 are diagrammatic partial views showing three different states of a second control panel according to the invention, and Fig. 5 is a diagrammatic partial view of a third embodiment of a control panel according to the invention.

Fig. 1 illustrates a first control panel constructed according to the invention.

The control panel has a supporting casing 1 which, during use, is secured in known manner in an aperture 2 in a wall 3 of a washing machine, e.g: for washing clothes or dishes.

In the embodiment shown diagrammatically by way of example, the control panel comprises a number of pushbutton control means A-N, each comprising a rod or shaft 4 axially movable through an aperture 5 in a front wall in the supporting casing 1.

The ends of the push-button control means extending outside the casing 1 have respective heads 6 which can be manually operated so as to change over each pushbutton control means from an axial switched-on position to an axial switched-off portion and vice versa.

The push-button control means A-N are associated with respective resilient means tending to push them towards the respective switched-off positions. In the embodiment diagrammatically shown, the resilient means comprise helical springs 7 disposed between the heads 6 of the means and the outer surface of the front wall of the casing 1. However, the means can be disposed differently, more particularly inside the casing 1.

The push-button control means in the control panel are for actuating or presetting a particular operation or cycle of the machine.

One of the push-button control means, more particularly the means indicated by A in Fig. 1, is for connecting the machine to a voltage supply, more particularly the electric mains. For this reason, the push-button control means A will be called the "principal pushbutton means".

The push-button control means in the control panel are associated with respective retaining mechanisms adapted, during operation of the machine, to hold them in the respective switched-on position, of course after they have first been pressed by the user.

By way of example, the retaining means can be of the kind shown in Fig. 1 in the case of the principal pushbutton control means A.

The retaining means mainly comprise a slider 8 mounted for movement inside the casing 1 in a direction at right angles to the axis of the associated push-button control means. In Fig. 1, the slider 8 is shown movable below the rod or shaft 4 of the push-button means A and its top surface is formed with an approximately heart-shaped guide groove 9, the surfaces or lateral edges of which serve as a guide for a peg 10 projecting from the bottom surface of the rod or shaft 4 of the push-button means A.

The side walls or edges of the groove 9 define desmodromic-type cam surfaces such that when the pushbutton A is pressed, the associated peg 10 travels along the right-hand branch (in Fig. 1) of the groove 9 until it reaches a cavity 11 on the inner edge of the groove. When the peg 10 engages in the recess 11, it retains the push-button A in the axial switched-on position. In this position, a pair of contact means 12 carried by the shaft or rod 4 electrically connects a pair of input terminals 13 of the control panel to a pair of output terminals 14. The input terminals 13 are adapted to be connected to the electric mains, whereas the output terminals 14 are directly or indirectly connected to all the electric or electronic devices inside the washing machine.

If the principal push-button A is pressed while in the previously-described switched-on position, the peg 20 becomes disengaged from the recess 11 in groove 9, and travels along the left branch (in Fig. 1) of the groove and, under the action of spring 7, returns to its extended or switched-off position (shown in Fig. 1) in which the input terminals 13 are disconnected from the output terminals 14.

The control panel in Fig. 1 is associated with an electrically controlled actuator 20 comprising a control rod 21 facing the slider 8 associated with the principal push-button control means A. The actuator can e.g. be electromagnetically controlled, i.e.

comprising an excitation solenoid and a movable core, or a cylinder and piston actuator in which the piston is movable through thermal expansion of a waxy material disposed in one of the two chambers in the cylinder, the expansion being brought about by electrically energising an associated heating resistor.

Of course, the actuator 20 can be of other known kinds.

The control rod 21 of the actuator 20 is coupled to a tension means 22 by a pre-loaded tension spring 23.

The tension means 22 has a head 24 which is held in a cavity or seat 25 in an attachment 8a at the end of the slider 8.

The spring 23 connecting the actuator rod 21 to the tension means 22 is adapted, when the actuator 20 is inactivated, to move the slide 8 when the principal control push-button A is switched on or switched off.

The actuator 20 is controlled by a monitoring device 30 adapted in known manner to detect faults or breakdowns in the washing machine, e.g. an excessive increase in the temperature of the water in the washing chamber or an excessive level reached by the water in the washing chamber or clogging of the filters, etc.

If a fault or breakdown of this kind occurs during operation of the machine, the monitoring device 30 actuates the actuator 20, whose rod 21 moves to the right in Fig. 1 and moves the slider 8 to the right, via spring 23 and the tension means 22 - 24. This movement of the slider disengages the peg 10 of the principal control push-button A (during operation of the machine, the peg engages in cavity 11 in groove 9) and the push-button A, under the action of the return spring 7, automatically returns to the switched-off position and disconnects the washing machine. The machine stops operating.

The aforementioned arrangement therefore automatically switches off the electricity supply to the washing machine when a fault or breakdown occurs in operation.

In addition, the position of the principal control push-button A, when returned to the switched-off position by the actuator 20, itself constitutes a sort of visual signal to the user (who of course will know whether or not he himself has disconnected the pushbutton), showing that a fault has occurred during operation of the machine.

In the control panel in Fig. 1, the control push-button A is of use not only as a principal or on/off pushbutton but also as a reference push-button, adapted to supply the user with a visual indication that a fault has occurred in operation.

Figs. 2 to 4 show a variant embodiment in which the function of a reference push-button for indicating faults or breakdowns in operation is performed by a supplementary push-button control means indicated by X, i.e. more particularly distinct from the principal push-button means A.

The reference push-button X is not associated with activation or presetting of specific functions or operating modes of the machine, but is adapted only to supply the user with a visual signal when a fault or breakdown occurs.

The control panel in Figs. 2 to 4 is constructed so that the reference push-button X is permanently held in the switched-on state (Fig. 2) from the time when the washing machine is manufactured until a first fault or breakdown occurs, after which the reference push-button automatically changes over to the switched-off position as we shall see (Figs. 3 and 4). The solution illustrated is as follows: until the first malfunctioning or fault occurs, the reference pushbutton X cannot be manually returned to the switchedoff position but, as stated hereinbefore, remains permanently in the switched-on position, whether the washing machine is in operation or is inactivated.

For reasons which will be clearer hereinafter, the reference push-button X is preferably disposed adjacent the principal push-button A.

The rod or shaft 4 of the reference push-button X is associated with a stopping means 30, likewise in the form of a slider movable axially in guided manner inside the supporting casing 1, in a direction at right angles to the axis of the rod or shaft 4. The stopping means 30 has a substantially L-shaped aperture 31 comprising a main branch 32 parallel to the axis of the shaft or rod 4 and a secondary branch 33 extending at right angles to branch 32.

The intermediate portion of the rod 4 has a projection 40 adapted to engage in the branch 32 or branch 33 of the aperture 31 in the stopping means,30.

When the control panel is manufactured, the push-button X is disposed so that the projection 40 engages the branch 33 of opening 31, as shown in Fig. 2, when the stopping means 30 is held in the illustrated position by action of a spring 35. In this state, the reference push-button control means X is held in the switched-on position.

In Figs. 2 to 4, reference 20 indicates an electrically controlled actuator similar to the device described previously with reference to Fig. 1. The actuator has a movable control rod 21 ending in a head 24 held in a seat or cavity 25 in an attachment 30a at the end of the stopping means 30.

When a fault or breakdown occurs during operation of the machine, the actuator 20 is energised and its rod 21 moves to the right in Fig. 2 and entrains the stopping means 30. The projection 40 on the reference push-button X is then opposite the branch 32 of the aperture 31 in the stopping means. As a result of being pushed by the return spring 7, the reference push-button control means X changes into the extended or switched-off position, showing the user that a fault or breakdown has occurred during operation of the machine (Fig. 3).

Advantageously though not necessarily, the rod 4 of the reference push-button X can be associated with a contact means 36 adapted, when the push-button is disconnected, to close a circuit for actuating a signalling lamp L. The lamp provides an additional visual signal for the user.

Instead of or in addition to a lamp, the additional signal can be given by a hooter.

When the fault has come to an end or the breakdown has been repaired, the reference push-button X can be returned to the switched-on position shown in Fig. 2.

Advantageously though not necessarily, the principal control push-button A, as already stated, is disposed adjacent the reference push-button X. The main pushbutton A is also associated with an additional stopping means 50, likewise in the form of a slider mounted for movement in guided manner inside the supporting casing 1 of the control panel and in the same direction as the stopping means 30.

The stopping means 50 likewise has an aperture 51, substantially in the shape of an L rotated through 180C and with two branches 52, 53, one branch being parallel and the other branch at right angles to the axis of the rod 4 of the push-button A. A projection 60 on the rod or shaft 4 of the principal push-button A extends in the aperture in the stopping means 50.

The stopping means 50 is normally disposed in contact with the stopping means 30, as shown in Fig. 2, and its projection 60 engages the top edge of the projection 51 therein.

The principal control push-button A can normally be switched on or switched off by energising or deenergising the washing machine.

The stopping means 50 and 30 are connected by a spring 70 tending to pull them towards one another.

If a fault or breakdown occurs during operation of the washing machine, the control means comprising the reference push-button X changes over to the switchedoff position (Fig. 3) through actuation by the actuator 20.

As previously described, the actuator, when energised, moves the stopping means 30 to the right in the drawing. The actuator also tends to move the stopping means 50 towards the right, but this movement is prevented by engagement of the projection 60 on the principal push-button A in the bottom branch 52 of the aperture 51. Consequently, the only result of actuating the actuator 20 is to move the stopping means 30 and tension the spring 70.

If the user, after noticing that the reference pushbutton X has moved to the switched-off position (Fig.

3) acts on the principal control means A so as to switch off the machine, the projection 60 on the pushbutton control means will engage the top part of the aperture 51 of the stopping means 50, thus moving it towards the stopping means 30 under the action of spring 70 (Fig. 4). The projection 50 on the principal push-button A will then engage in the branch 53 of aperture 51 in the stopping means 50, and cannot be subsequently pressed so as to reactivate the washing machine.

The stopping means 30 and 50 and the associated pushbuttons X and A cannot be re-positioned until the fault or breakdown in operation of the washing machine has been eliminated.

Fig. 5 shows another variant, likewise comprising a supplementary push-button control means X for indicating faults or breakdowns during an operating cycle of the washing machine. In Fig. 5, parts or elements already described are given the same alphanumeric references as before. In the variant in Fig. 5, the electrically controlled actuator 20 is coupled not only to the stopping means 30 (as in the variants in Figs. 2 - 4) but also to an attachment 8a on the slider 8 associated with the principal pushbutton control means A.

Accordingly, the actuator 20 is adapted to move two rods 21 and 121, the second of which is coupled (via a pre-loaded tension spring 123) to the rod 122 of a tension means comprising a head 124 which engages in a predetermined seat or cavity 125 in the slider 8.

If a fault or breakdown in operation occurs, the actuator moves in the stopping means 30 and cursor 8 to the right in Fig. 5. Correspondingly, the reference push-button X changes over to the switched-off state, providing a visual signal for the user. In addition, the main push-button A moves from the switched-on position to the switched-off position, thus cutting off the electricity supply for the washing machine. The stopping means 50 engages the projection 60, preventing subsequent switching-on of the principal push-button A. Of course, without altering the main features of the invention, the embodiments and practical details can differ widely from those described and illustrated by way of non-limitative example only, without thereby departing from the scope of the invention.

Claims

1. A control device, more particularly for a domestic electrical appliance such as a washing machine, comprising a support structure for securing in an aperture in a wall of the machine, a number of pushbutton control means mounted for movement in the structure and adapted to take up a switched-on position and a switched-off position, and mechanical retaining means borne by the structure and adapted, during operation of the machine, to retain one or more pushbutton control means in respective switched-on positions, characterised in that the device is associated with an electrically controlled actuator including a control element coupled in operation to the mechanical retaining means associated with a reference push-button control means adapted during operation of the machine to remain in the switched-on position so as automatically, during operation of the machine, to move the reference push-button means to the switched-off position when a control signal is applied to the actuator.

2. A device according to claim 1, comprising a principal push-button control means which, when switched on, closes an electric switch for connecting the machine to a voltage supply, more particularly to the electric mains, characterised in that the reference push-button control means is the principal push-button control means.

3. A device according to claim 1, characterised in that the reference push-button control means is an additional push-button control means for signalling.

4. A device according to claim 2, in which the retaining means associated with the principal pushbutton control means comprises a slider adapted to slide in reciprocation in the support structure in a direction at an angle to the direction of motion of the push-button control means and comprising desmodromic cam means for co-operating with a portion of the pushbutton control means so that the cam means are adapted, after successive actuation of the push-button means, to retain the means in the switched-on condition and to return it to the switched-off position under the action of resilient return means, characterised in that the control element of the actuator is associated in operation with the slider and is adapted to position it so as to release the principal push-button means from the switched-on position.

5. A device according to claim 3, characterised in that the retaining means comprise a movable stopping means which, when the actuator is in the inactivated state, is adapted to hold the supplementary push-button means permanently in the switched-on state, whether the machine is activated or not, the actuator being adapted, when actuated, to move the stopping device to a position where the supplementary push-button means is released and can thus return to the switched-off state under the action of resilient return means.

6. A device according to claim 5, comprising a principal push-button control means which, when switched on, closes an electric switch for connecting the machine to a voltage supply, more particularly the electric mains, characterised in that the principal push-button means is associated with a second stopping means adapted to take up a first position for moving the principal bush-button means from the switched-off state to the switched-on state and vice versa, and a second state in which it prevents the principal pushbutton means from moving into the switched-on state, and the stopping means associated with the supplementary push-button means is coupled during operation to the second stopping means so as to move it to the second position after actuation of the actuator and after the principal push-button means has changed to the switched-off state.

7. A device according to claim 6, characterised in that the first and second stopping means comprise a first and second slider respectively, mounted for movement in the support structure in a direction at an angle to the direction of motion of the associated principal and supplementary push-button means, the actuator being adapted, when activated, to move the first stopping means away from the second stopping means, and the stopping means being interconnected by a resilient means adapted to move the second stopping means to the aforementioned second position by returning it towards the first stopping means when the principal push-button control means returns to the switched-off state.

8. A device according to claim 7, characterised in that it comprises additional resilient means for moving the first and second stopping means into the normal working position when the actuator is inactivated.

9. A device according to any of claims 5 to 8, in which the retaining means associated with the principal push-button control means comprises a slider mounted for reciprocal motion in the support structure in a direction at an angle to the direction of motion of the principal push-button control means and comprising desmodromic type cam means co-operating with a portion of the principal push-button control means in such manner that the cam means are adapted, after successive actuation of the principal push-button means, to retain the means in the switched-on condition and to return it to the switched-off position under the action of resilient return means, characterised in that the control element of the actuator is also associated in operation with the slider and, when the actuator is in the activated condition, is adapted to move it so as to release the principal push-button means from the aforementioned switched-on position.

10. A device according to claim 3 or any of claims 5 to 9, characterised in that the supplementary pushbutton means is associated with an electric switch adapted to activate an optical and/or acoustic signalling device when the supplementary push-button control means is in the switched-off state.

11. A device substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.