GB2170048A - Feeler or cam-follower for actuating a programmer switch - Google Patents

Abstract

This invention relates to an improved feeler for programmers applicable to household appliances, such as washing machines or dishwashers, wherein the programmer includes a fast and a slow programme cam, the feeler being actuable by either one of the cams, whereby the number of electrical contacts can be reduced. The feeler includes a plurality of bevelled ends 3', 3'', each cooperating with a cam track. A projection 9', or 9'' is used to operate the contacts of a switch in response to either end 3' or 3''. <IMAGE>

Description

SPECIFICATION An improved feeler for programmers applicable to household appliances This invention, as stated in the title of this Specification, refers to a feeler for programmers, of the type used in household appliances, such as washing machines or dishwashers, which has been considerably improved to enable substantial simplification in the programmer structure, especially regarding the number of contacts involved, without reducing the functional performance offered by it.

Control devices by programmes, designed for household machines, like those quoted above, which operate according to preset work cycles, generally consist of a series of electric contacts, either in the form of simple switches or commutators, which are driven through sliding feelers, by two programme support elements, which generally adopt a disc or drum shape, including a plurality of cams which, at the required moment and during a likewise programmed time, act on the feelers and, through them, determine the opening or temporary closing of of the machine's different circuits.

One of these programme support elements, i.e., one of these cam discs or drums, the one normally called "slow" generally advances step by step, according to preset time sequences, so that it remains in each of its positions during different periods of time, while the other "fast" programme support is either provided with continuous movement or also goes forward step by step, staying in each of its positions normally for a constant period of time, and generally much less than the time the "slow" programme support remains in its shortest position.

The different programmes of these machines represent the continuous performances of a series of characteristic operations. For example, in the case of washing machines, water intake, with or without washing products, heating the washing bath, mechanical stirring of the clothes inside it, removing the "dirty" water, etc., constitute some of these operations.

These basic operations are governed by electric contacts linked in the "slow" cam disc or drum, while the electric contacts associated with the "fast" cam disc or drum, duly connected to the different machine circuits, in series with some of those linked to the "slow" cam disc or drum, in turn control generally repetitive operations, lasting less time than the basic operations, and which affect one or more of these basic operations.

All this calls for a relatively high number of electric contacts, and causes a degree of complexity in circuits which involves a considerable increase in the cost of the product, its size and the risk of breakdown.

A programmer of this type is the one illustrated in Utility Model no. 204,785, held by the same applicant, and the improved feeler which the invention proposes is particularly applicable to a programmer like the one in the said Utility Model, achieving a noteworthy structural simplification and, consequently, eliminating or reducing the aforementioned problems.

More specifically, the feeler which the invention proposes has been specially designed to receive indistinctively the drive of respective cams corresponding to the two programme supports, slow and fast, specifically to two cams which, according to the different stages of the programme must close the same circuit, act on a single contact, since, as we have already said, it concerns closing the same circuit in both cases.

In this connection, and merely as an example, the case can be quoted of a motor, a valve or any other element which, according to a present programme stage in the fast support, must also be activated during another period of time through the slow programme support in a programmer like the one disclosed in Utility Model 204,785, in which two feelers are used, one for the slow support and the other for the fast support which act on respective sets of electric contacts, also independent, but which however are connected to the same element, whereby the latter is activated through both contacts in series.

Well now, the object of the invention, particularly in cases of functions which have to occur in given positions of the slow support and whose duration must be less than the time it remains in those positions, is to reduce to half the number of electric contacts necessary in the programmer to obtain the same results, nevertheless maintaining the features of the programme supports, which in practice is extremely advantageous, as there are numerous electric contacts which can be eliminated with the consequent economic repercussion.

Hence, and more specifically, the programmer maintains its structural features, in accordance with the aforementioned Utility Model, i.e. regarding a flattened body in which the fast and slow programme supports are arranged on one of its sides, whose cams touch a plurality of pushers which cross the said flattened body and which, in their displacement, are guided perfectly through partitions in the opposite side of the body, which also act as separators for the groups of contacts which are to be materialized in respective simple switches or commutators, but with the special features, and it is this which constitutes the essence of the invention, that the feelers which in principle were to act on different groups of contacts corresponding to the electric supply circuit of a certain device, are physically linked together, like a single part, including respective ends emerging towards the side of the flattened body in which the programme supports are placed, with their fronts bevel-edged and operatively placed opposite the cams of the latter, while in the location area of the contacts, pushers are included which in principle could be reduced to a single pusher, specifically the one which is to touch the sole group of contacts, but which optionally could also be several, to be able to select the location of the single group of contacts mentioned above, as wished, within the multiple possibilities offered by the feeler.

From this basic structure, the feeler which the invention proposes can have bevel-edged attach fronts for the adjacent cams, or by substantially separated, having other complementary feelers between them, as each case requires, and without this affecting the essence of the invention.

To complete the description being made, and to assist a better understanding of the features of the invention, drawings are attached to this Specification, as an integral part thereof, in which the following has been shown, with a illustrative and unlimiting nature: Figure 1 shows a plan view of the main body, corresponding to a programmer applicable to household appliances, made according to the object of the invention, in which it can be seen how the said body is similar to that used in a conventional programmer, like the object of Utility Model 204,785.

Figure 2 shows a cross-section detail of the body shown in the previous figure, on a level of one of the housings for a group of contacts, in which this group of contacts appears, as well as the respective feeler and the drive cam of the latter, corresponding to the programme support, all in accordance with conventional engineering, according to which each feeler constitutes an independent element, which drives the likewise corresponding set of contacts.

Figure 3 shows a plan view detail of the assembly illustrated in the previous figure.

Figure 4 shows a similar illustration to that given in figure 3, but corresponding to a programmer executed in accordance with the object of this invention, in which the feeler is multiple, to be precise, double.

Figure 5 shows a perspective detail of the feeler illustrated in figure 4, individually.

Figure 6 shows another illustration, similar to that in figure 4, but corresponding to another example of practical embodiment of the feeler, in the case of two cams, not adjacent, acting on it.

Figure 7 finally shows a perspective view of the feeler corresponding to a practical embodiment of figure 6, with a similar illustration to figure 5.

In the light of these figures it can be seen how the programmer made in accordance with the object of this invention has a flattened body 1, similar to that of a conventional programmer, and provided for this purpose with a longitudinal alignment in the middle of small windows 2, through which the bevelled ends 3 of the respective feelers emerge, to be driven by the cams placed in the programme supports 4 and 5, shown by a dotted line in the said figure 1, reference no. 4 corresponding to the fast programme support, while reference no. 5 corresponds to the slow programme support.

In figures 2 and 3 the unit structure has been illustrated corresponding to each contact in accordance with conventional engineering, so that cam 6 corresponding to a given programme support 4-5, acts on a feeler 3 which emerges towards the side of the body 1, opposite that shown in figure 1 and which is mounted in the said body in a sliding manner, in a groove 7 and through a transversal branch 8 made therein, while it has a side projection 9 which, in the example of embodiment shown in figure 2, touches a moving contact 10 of a commutator, establishing the inoperative position for it, shown in that figure, or closing a circuit through the lower contact 11, or a second circuit through the top contact 12.

In accordance with this classic layout, each programme stage arranged in supports 4 and 5, through their multiple cams 6 requires a feeler 3 and consequently a set of electric contacts 10-1112.

According to the invention, two feelers 3' and 3", designed to receive the drive of cams corresponding to the two fast and slow programme supports 4 and 5, which correspond to the same operative stage, i.e., to a given drive on the same element of the household appliance, are inter-related, like a single part through the intermediate joining sector 13, as a single part, so that they are driven simultaneously, whether through the cam of one or other programme supports, as in either case, the same effect is sought, although with different intensity regarding time.

The feelers linked together in a single part can occupy adjacent positions, as shown in figures 4 and 5, of different alternating positions, like the example illustrated in figures 6 and 7, their configuration and dimensions varying as needed in each case, and without this affecting the essence of the invention.

In any event, and as illustrated in figures 4 and 6, the double feeler is going to act on a single group of contacts 10' since as they are joined in a single part, the second group of contacts is unnecessary and so will be eliminated.

Although in the figures the double feeler also provided with two pushers 9' and 9" has been shown it is obvious that only one of them will be operative, specifically that corresponding to the set of contacts 10', so the other may be deleted; nevertheless, in this preferential example of embodiment, it has been kept, as it hardly makes the feeler any more expensive and, on the other hand, it enables a choice to be made between both possible receptacles for placing the set of contacts, whichever proves most suitable, provided the number of conventional housings is maintained, for obviously it is also possible to adapt the structure of the main body to the final number of housing which are going to be necessary on applying the object of the invention, considerably more reduced than in classical programmers of this type.

The fact should also be mentioned that the practical solutions illustrated in figures 4-5 and 6-7 are given merely by way of example, and that the feeler can adopt any other configuration, according to the needs and demands of each case, without this affecting the essence of the invention, which is centered exclusively on the fact that the feelers for two sets of contacts, corresponding in turn to the cams of two supports, and which are to act on the supply circuit of the same element, and in similar conditions, are joined together as a single part, forming a double feeler, which can be driven indistinctively by one cam or other, and which in turn drives a single group of contacts.

It is not considered necessary to make this description any more lengthy for an expert on the matter to understand the scope of the invention and the advantages derived therefrom.

The materials, shape, size and layout of the elements will be liable to variation, provided this does not involve altering the essential nature of the features of the invention.

The terms in which this Specification has been drawn up should always be taken in their fullest and unlimiting sense.

Claims (2)

1. -An improved feeler for programmers applicable to household appliances, specifically for programmers in which two programme supports are established, one for fast movement and the other for slow movement which, through respective sets of cams, act on these feelers so that they open or close the respective sets of contacts, essentially characterized in that it has a dual construction, so that it includes two bevelled ends on which the respective cams of the said programme supports operate, while the said feeler acts in turn exclusively on a single set of contacts, it having been foreseen that its two bevelled ends are linked with cams of two programme supports designed to control the drive of the same mechanism of the household appliances in operative stages with different time ranges, all so that the thrust supplied to the feeler by either of the cams linked to it, i.e., by any one of the two programme supports, drives a single group of control contacts for the said mechanism, whichever programme support has shifted the feeler and during the time set in either programme support.

2. -An improved feeler for programmers applicable to household appliances, substantially as hereinbefore described with reference to Figures 4 to 7 of the accompanying drawings.