EP2479768B1

EP2479768B1 - Switch device for a household appliance

Info

Publication number: EP2479768B1
Application number: EP20120425009
Authority: EP
Inventors: Fabrizio Promutico
Original assignee: Bitron SpA
Current assignee: Bitron SpA
Priority date: 2011-01-24
Filing date: 2012-01-18
Publication date: 2013-10-16
Anticipated expiration: 2032-01-18
Also published as: IT1404222B1; EP2479768A1; ITRM20110027A1

Description

The present invention relates to a switch device.
More specifically, the invention concerns a rotary switch device designed and realized both for turning on and off a domestic household appliance, as well as for selecting a plurality of operating programs, allowing a high energy saving.
In the following, the description will be directed to a washing machine, but it is clear that the same should not be considered limited to this specific use.
Document DE 3 504 135 discloses a device according to the preamble of claim 1.
As it is well known, in the field of household appliances, and in general of the home automation, an important objective is to reduce the consumption of electrical energy. For this purpose, a directive is already in force, which provides for the obligation already from 2013 to eliminate the consumptions of household appliances even during standby. From a technical point of view, this means that a physical opening of the connection of the household appliance from the electricity network should be provided, so as to prevent any current consumption both when the user so decides, for example when he turns off the machine, as well as when the household appliance completes an operating program.
Currently there are several rotary switch devices, which allow the selection of different programs, the switching on and off of the household appliance itself, but they are not capable of automatically opening the connection of the household appliance from the supply network at the end of an operating program.
In view of the above, it is, therefore, object of the present invention providing a rotary switch device capable to overcome the limitations of the prior art.
An object of the present invention is to allow the opening from the network both manually as well as automatically, by means of an electronic control.
These and other results are achieved according to the invention with a switch device for an apparatus, such as a household appliance, a washing machine or the like, capable of connecting or disconnecting mechanically the power supply of the apparatus, but that it can also automatically disconnect the power supply by means of an electronic control.
It is therefore a specific object of the present invention switch device for an apparatus such as an household appliance, a washing machine or the like, comprising a containment enclosure, a coding unit for the selection of operating programs of said apparatus, said coding unit comprising a rotatable switch body, characterized in that said device comprises a power unit comprising network electrodes, connected to the electricity network for powering said apparatus, and movable power electrodes, said power unit also comprises an activating lever interacting with said switch body and with said power electrodes, said activating lever being capable to assume a resting position and an operating position following the rotation of said switch body, in said resting position said power electrodes are not connected with said network electrodes, and in said operating position said power electrodes are connected with said network electrodes for supplying said apparatus, and in that said device comprises means for controlling said activating lever controlled by an electrical signal and suitable to bring said activating lever from said operating position to said resting position.
Always according to the invention, said switch body of said coding unit could comprise includes a selection disk provided with a first face and a second face, opposite to said first face, said second face having a release tooth and an activation crown gear circularly arranged, and said activating lever could comprise above one or more teeth and below a first relief and a second relief, said first relief being capable to interact with said release tooth, so that said activating lever passes from said operating position to said resting position, and said teeth disengage from a groove, and said second relief interacting with said activation crown gear, so that said activating lever passes from said resting position to said operating position, and said teeth engage with a suitable groove of said containment enclosure.
Still according to the invention, said control means could comprise a coil, a core movable due to the magnetic field generated by said coil when said coil is powered, said movable core interacting with said relief of said activating lever, so as to cause the transition of said activating lever from said operating position to said resting position when said coil is powered.
Advantageously according to the invention, said control means could comprise a bi-metal element, interacting with said activating lever, and a PTC (Positive Temperature Coefficient) resistor, arranged close to said bi-metal element, so that the current passing through said PTC resistor causes an increase of the temperature of the PTC resistor itself and of the bi-metal element, said bi-metal element, changing its shape, moves said activating lever, passing it from said operating position to said resting position.
Further according to the invention, said first face could comprise crown gears or relief for program selection and in that said coding unit comprises a plurality electrical contacts, with which said crown gears or relief for program selection interact, so as to open or close said electrical contacts for the selection of operating programs of said apparatus.
Always according to the invention, said power unit could comprise an activating module, located in said containment enclosure and vertically arranged, said activating module being provided with terminals and being suitable to enable the power of said control means.
Still according to the invention, said activating module could comprise an active device, such as a TRIAC.
Further according to the invention, said device could comprise selection control means interacting with said selection disk, so that said switch body being a stepwise switch body.
Advantageously according to the invention, said first face of said selection disk could comprise a selection crowned gear having teeth with a rounded shape, and in that said selection control means comprise: a lever element, having a hole and inserted into a circular groove obtained on said second face of said selection disk, said lever element including an arm coupled with said lever element, having a seat at the end; a selection element, such as a sphere, housed in said seat of said selection lever element and capable to slide over the teeth of said selection crowned gear; and a spring, arranged in compression between said lever element and said containment enclosure, suitable to eliminate mechanical play ensuring the electrical contact of electrical contacts for program selection.
The present invention will be now described, for illustrative but not limitative purposes, according to its preferred embodiments, with particular reference to the figures of the enclosed drawings, wherein:

figure 1 shows a switch device according to the present invention;
figure 2 shows an exploded view of the device according to figure 1;
figure 3 shows a plan view of the device according to figure 1;
figure 4 shows a section along the line A-A of the device according to figure 3;
figure 5 shows a section along the line B-B of the device according to figure 3;
figure 6 shows a section along the line C-C of the device according to figure 3;
figure 7 shows a section along the line D-D of the device according to figure 3;
figure 8 shows a section along the line A-A of the device according to figure 3 during operation;
figure 9 shows a section along the line B-B of the device according to figure 3 during operation;
figure 10 shows a section along the line C-C of the device according to figure 3 during operation;
figure 11 shows a detail of the device according to figure 1;
figure 12 shows the device according to figure 1 in which the activating lever is in resting position;
figure 13 shows the device according to figure 1 in which the activating lever is in operating position;
figure 14a shows a first embodiment of the activating module according to the present invention;
figure 14b shows a second embodiment of the activating module according to the present invention; and
figure 14c shows a third embodiment of the activating module according to the present invention.

In the various figures, similar parts will be indicated by the same reference numbers.
Making reference to figures 1-7, it can be seen the structure of a rotary switch device 1 for an apparatus (not shown in the figure), like a washing machine or a household appliance in general, comprising mainly a coding unit 20 and power unit 30, interacting each other, to allow on the one hand the activation of the apparatus, and on the other hand the automatic turning off of the apparatus itself, after the selection and the completion of an operating program.
Said coding unit 20 and power unit 30 are placed in a containment enclosure having a first base element 41, fixable by means of suitable supports 41' to the motherboard of the apparatus, and a second closure element 42.
Said coding unit 20 comprises a switch body 21, rotatable with respect to a rotation axis by means of a knob (not shown in the figures) by a user. Said switch body 21 provides with a selection disc 22 having a first face 221, on which crown gears or reliefs for program selection 23 are obtained, and a second face 222, opposite to said first face 221, on which a release tooth 24, an activation crown gear 25, whose teeth have, in the present embodiment, a triangular shape, and a further selection crown gear 26, whose teeth, in the present embodiment, have a rounded shape, are obtained. Said coding unit 20 has also a plurality of electrical contacts 27, which interact with said crown gears or reliefs for program selection 23. Said crown gears or reliefs for program selection 23, when said switch body 21 is rotated, close one or more contacts 27 selecting an operating program.
The power unit 30 of the switch device 1 comprises power electrodes 31, each having, preferably, an air distance of at least three millimeters for normative reasons, for the conduction of the current necessary to the operation of the apparatus. Each of said power electrodes 31 is made of metal and are in this embodiment "L"-shaped, so as to be deformable at least in part and to assume, due to elastic properties of the metals, their previous shape. Said power electrodes 31 are arranged so as to assume a first position, in which they are disconnected from corresponding network electrodes 31', connected to the electricity network, and a second position, in which they are forced, due to, as mentioned above, their elasticity, to be in contact with said network electrodes 31', for the power supply of said washing machine or apparatus in general.
The power unit 30 also includes an activating lever 32 having at the top a pair of teeth 321 and at the bottom first relief 322 and a second relief 323, the latter having a shape substantially complementary to the spaces between the teeth of said one activation crown gear 25.
Said activating lever 32 is capable of interacting with said power electrodes 31 and with said release tooth 24. In particular, said activating lever 32 is arranged so as to be able, as it will be better described below, to assume a resting position and an operating position. In said resting position, said activating lever 32 is lowered and said second relief 323 is between two teeth of said activation crown gear 25. Instead, when said activating lever 32 is in said operating position, it is lifted and slightly rotated with respect to an axis transversal to the rotation axis of said switch body 21. In this way, said teeth 321 engage with a suitable groove 42 obtained within said second closure element 42, and bringing said power electrodes 31 from said first position to said second position, in which they are in contact with said network electrodes 31'.
Said power unit 30 also comprises control means that can be activated by the logic of the washing machine or household appliance in general. Said control means comprise, in particular, a coil 33 provided with a movable core 34, made of ferromagnetic material and capable of interacting with said relief 322 of said activating lever 32. According to the arrangement of the present embodiment, when said movable core is extracted in whole or in part by said coil 33, the power supply of said coil 33 causes the attraction of the movable core 34 itself in its interior.
An activating module 35 is associated with the coil 33, said activating module 35 being connected and controlled to / from a control logic unit arranged on said mother board of the household appliance by means of terminals 35', arranged below, or 35", arranged above. Said activating module is connected so as to enable or disable the power supply of the coil 33.
Preferably, device 1 can also comprise step selection control means 50, which comprise a lever element 51 having a hole 51'. Said lever element 51 is inserted into a circular groove 28 obtained on said second face 222 of said selection disc 22, so as to be concentrically arranged on said switch body 21. Said lever element 51 provides with an arm 51' having a seat 51" at the end, adapted to hold a selection element, which, in the embodiment concerned, is a sphere 52. Said selection control means 50 comprise also a spring 53, arranged in compression between said lever element 51 and said second closure element 42.
The operation of the rotary switch device 1 described above is as follows.
Starting from an initial reference position of the switch body 21, wherein the activating lever 32 is in said resting position and said second relief 323 is positioned between said release tooth 24 and the first of the teeth of said activation crown gear 25. Power electrodes 31, therefore, are in said passive position and are not in contact with network electrodes 31' (figure 12). Therefore, power supply does not reach the apparatus to be powered, for example a washing machine.
Referring now to figures 8 - 13, when the switch body 21 is rotated, the first of the teeth of said activation crown gear 25 interacts with said activating lever 32, lifting and rotating it according to the arrow R (see figures 8 and 13), causing it to assume said active position, so that said teeth 321 engage with said groove 42' of said second closure element 42, holding said activating lever 32 in said operating position (see again figure 8).
Said power electrodes 31, rising with said activating lever 32, are put in contact with said network electrodes 31' assuming said active position. Furthermore, when said activating lever 32 assumes said operating position, said first relief 322 moves said movable core 34, by pulling it out at least in part from said coil 33, which is not powered.
By further rotating said switch body 21, of an angle less than the round angle with respect to said initial reference position of said switch body 21, the second relief 323 of said activating lever 32 is always arranged in correspondence with said activation crown gear 25, without interacting with the teeth of the same.
In addition, crown gears or reliefs for program selection 23, as mentioned above, close one or more contacts 27, by selecting an operating program. Moreover, in the rotation o the switch body 21, even said lever element 51 rotates on said circular groove 28, together with the arm 51', which rolls said sphere 52 on said selection crown gear 26, while the spring 53 exerts its force on said lever element 51, which is pivoted on the point P, thus exerting, as a result, a resistance to the rotation in the passage of the sphere between a tooth and the other of said selection crown gear 26. Of course, selection crown gear 26 and crown gears or reliefs for program selection 23 are synchronized, so that for each step of the selection crown gear 26, i.e. during the rotation of said switch body 21 and at each passage of the sphere 52 between a tooth and the other of said selection crown gear 26, the activation of an operating program of the washing machine by means of crown gears or reliefs for program selection 23 takes place, with the appropriate closing or opening of said electrical contacts 27.
Once selected the operating program, being the washing machine powered, the latter can operate and run it.
At the end of the program, an appropriate signal is transmitted from said motherboard to said activating module 35, which enables the power supply of said coil 33, which generates a magnetic field which moves the movable core 34, attracting it in its interior. Said movable core 34 interacts with said first relief 322, bringing said activating lever 32 in said resting position. Said second relief 323 inserts, thus, between two teeth of said activation crown gear 25. In this way, the power electrodes 31, due to their elastic properties, disconnect from said network_electrodes 31', by disconnecting the power supply from the washing machine and eliminating any kind of passive current consumption.
For the following turning on of the apparatus, turning again said switch body 21 is sufficient. In this way, due to the triangular shape of the teeth of said activation crown gear 25, said activating lever 32 is raised again and rotated, causing it to re-assume said operating position, so that said teeth 321 engage with said groove 42' of said second closure element 42, holding said activating lever 32 in said active position.
In case of, for example, a program is not selected, or it is wished to turn off the washing machine while a selected program running and possibly it is already started, rotating the switch body 21 to return it back into said initial reference position, then said release tooth 24, which is arranged on a circumference having a radius greater than that identified by said activation crown gear 25, interacts with said second relief 323 of said activating lever 32 (which, of course, is in said operating position). Said release tooth 24, due to its shaping, returns said operating lever 32 in said passive position, so as to disconnect said power electrodes 31 from said network electrodes 31'.
The activating module 35 is adapted, as mentioned above, to activate the coil 33 and it can be controlled by a signal from the motherboard of the washing machine, and, therefore, from its logic.
Figures 14a-14c show three embodiments of the activating module 35 according to the present invention.
In particular, figure 14a shows a triac 36, connected between the coil 33 and the network. When an appropriate signal reaches gate G, triac 36 conducts and powers the coil 33.
Figures 14b and 14c show coil 33 connected with a network electrode 31', so that when a control signal comes from said motherboard, the coil is activated. Straight after, power electrodes 31 disconnect from said network electrodes 31', so interrupting even the power supply of the coil 33.
Finally, according to further embodiments, said control means can be realized through a bi-metal element, interacting with said second relief 323 of said operating lever 32, and a PTC (Positive Temperature Coefficient), arranged close to said bi-metal. In this way, a current that flowing through said PTC resistor causes an increase of the temperature of the PTC resistor itself, and then of the near bi-metal element, which in its turn changes its shape, moving said operating lever 32, passing it from said active position to said passive position.
The present invention has been described for illustrative but not limitative purposes, according to its preferred embodiments, but it is to be understood that modifications and/or changes can be introduced by those skilled in the art without departing from the relevant scope as defined in the enclosed claims.

Claims

Switch device (1) for an apparatus such as an household appliance, a washing machine or the like, comprising
a containment enclosure,
a coding unit (20) for the selection of operating programs of said apparatus, said coding unit (20) comprising a rotatable switch body (21), whereby
said device (1)
comprises a power unit (30) comprising network electrodes (31'), connected to the electricity network for powering said apparatus, and movable power electrodes (31), said power unit (30) also comprises an activating lever (32) interacting with said switch body (21) and with said power electrodes (31), said activating lever (32) being capable to assume a resting position and an operating position following the rotation of said switch body (21), in said resting position said power electrodes (31) are not connected with said network electrodes (31'), and in said operating position said power electrodes are connected with said network electrodes (31') for supplying said apparatus, characterized in that
said device (1) further comprises means (33,34) for controlling said activating lever (32) by an electrical signal to bring said activating lever (32) from said operating position to said resting position.
Switch device (1) according to claim 1, characterized
in that the said switch body (21) of said coding unit (20) comprises a selection disk (22) provided with a first face (221) and a second face (222), opposite to said first face (221), said second face (222) having a release tooth (24) and an activation crown gear (25) circularly arranged, and
in that said activating lever (32) comprises above one or more teeth (321) and below a first relief (322) and a second relief (323),
said first relief (322) being capable to interact with said release tooth (24), so that said activating lever (32) passes from said operating position to said resting position, and said teeth (321) disengage from a groove (42'), and
said second relief (323) interacting with said activation crown gear (25), so that said activating lever (32) passes from said resting position to said operating position, and said teeth (321) engage with a suitable groove (42') of said containment enclosure.
Switch device (1) according to claim 2, characterized in that said control means comprise
a coil (33),
a core (34) movable due to the magnetic field generated by said coil (33) when said coil (33) is powered, said movable core (34) interacting with said relief (322) of said activating lever (32), so as to cause the transition of said activating lever (32) from said operating position to said resting position when said coil (33) is powered.
Switch device (1) according to claim 2, characterized in that said control means comprise a bi-metal element, interacting with said activating lever (32), and a PTC (Positive Temperature Coefficient) resistor, arranged close to said bi-metal element, so that the current passing through said PTC resistor causes an increase of the temperature of the PTC resistor itself and of the bi-metal element, said bi-metal element, changing its shape, moves said activating lever (32), passing it from said operating position to said resting position.
Switch device (1) according to anyone of claims 2-4, characterized in that said first face (221) comprises crown gears or relief for program selection (23) and in that said coding unit (20) comprises a plurality electrical contacts (27), with which said crown gears or relief for program selection (23) interact, so as to open or close said electrical contacts (27) for the selection of operating programs of said apparatus.
Switch device (1) according to anyone of the preceding claims, characterized in that said power unit (30) comprises an activating module (35), located in said containment enclosure and vertically arranged, said activating module (35) being provided with terminals (35', 35") and being suitable to enable the power of said control means.
Switch device (1) according to claim 6, characterized in that said activating module (35) comprises an active device, such as a TRIAC (36).
Switch device (1) according to anyone of claims 2-7, characterized in that it comprises selection control means (50) interacting with said selection disk (22), so that said switch body (21) being a stepwise switch body (21).
Switch device (1) according to claim 8, characterized
in that said first face (221) of said selection disk (22) comprises a selection crowned gear (26) having teeth with a rounded shape, and
in that said selection control means (50) comprise: a lever element (51), having a hole (51a) and inserted into a circular groove (28) obtained on said second face (222) of said selection disk (22), said lever element (51) including an arm (51') coupled with said lever element (51), having a seat (51") at the end; a selection element, such as a sphere (52), housed in said seat (51") of said selection lever element (51) and capable to slide over the teeth of said selection crowned gear (26); and a spring (53), arranged in compression between said lever element (51) and said containment enclosure, suitable to eliminate mechanical play ensuring the electrical contact of electrical contacts (27) for program selection.