Patent Application
20130068600
This application claims priority to German Patent App. No. 10 2011 014 765.9, filed on Mar. 22, 2011, and German Patent App. No. 10 2011 016 945.8, filed on Apr. 13, 2011, the disclosures of which are incorporated by reference herein.
A switching device is specified which is capable of accurately switching between at least two switch positions.
A switching device as mentioned above is disclosed in JP 2010073662 A. Said switching device has the disadvantage that it is formed by a very complex assembly.
In consideration of this situation, the primary object of the invention is to provide a switching device according to the preamble of claim 1 which has a simpler assembly and operates more reliably.
The solution of this technical problem is provided with the features of the main claim, whereas advantageous designs and further developments of the invention can be inferred from the dependent claims.
The technical problem is solved in the switching device which has a housing, an actuator for receiving a pressure two or more actuation and at least two or more metal contact elements. At least one contact element forms a common contact point, and at least one contact element is a switching contact. The contact elements are electrically contactable from the outside of the housing. The switching device has a snap-action switching mechanism which is actuated when the actuator is pressed into the designated position. The snap-action switching mechanism has at least a first actuator-element on which at least one contact part for the disconnection and/or contacting with the at least one switching contact is mounted in the region of a first end. The first actuator-element is pivot-mounted with the second end at the common contact point. The snap-action switching mechanism has a second actuator-element which is capable of receiving a pressure actuation by means of the actuator via a first end. The second actuator-element is pivot-mounted at its second end on the inner edge of the housing opposite to the common contact of the housing. The second actuator-element is pivot-mounted at its second end on the inner edge of the housing which is opposite to the transverse side with the common contact of the housing. A tension spring is located between the first actuator-element and the second actuator-element.
A preferred embodiment of the switching device is characterized in that the second actuator-element has at least one recess at its second end. Preferably, at least one projection engages with the recesses, with the projection being attached to an inner edge of the housing on which the second end of the second actuator-element is mounted. Due to the projection, the second actuator is secured against lateral slipping. Preferably, the shape of the projection is adapted to the shape of the recess of the second actuator such that they can engage with each other. Instead of a recess, two or more recesses can also be provided at the second end of the second actuator-element. Accordingly, in this case there is a plurality of suitable projections on the inner edge of the housing.
Another preferred embodiment of the switching device is characterized in that the contact part being connected to the first actuator-element is pre-stretched against the switching contact. Due to the pre-stretching of the contact part, it is ensured that the contact part produces sufficiently high sliding resistance, which has to be overcome by the movement of the snap-action switching mechanism. In the event that the tensioning force of the tension spring between the first and second actuator-element is higher than the sliding resistance of the contact part, the snap-action switching mechanism snaps over and the contact part snaps from the switching contact into a resting position and/or from the resting position to the switching contact. In the event that no more pressure is applied to the actuator, the snap-action switching mechanism snaps back into its stable starting position due to the tensioning force of the tension spring. At this, the contact part slips back to the switching contact and/or into the resting position.
Preferably, at least one switching contact is arranged laterally towards the inner wall of the housing. The contact part connected to the first actuator-element is arranged between the first actuator-element and the switching contact. Preferably, the switching contact is arranged such that it is in contact with the inner surface of the housing, or it is disposed in a recess of the inner surface. In an embodiment of the switching device having two switching contacts, the inner wall between the switching contacts preferably forms a smooth transition. Thus, the contact part can slide between the two switching contacts without having to overcome an additional obstacle. For a defined desired increase and/or reduction of the sliding resistance of the contact part, the switching contact itself and/or switching contacts themselves may, however, have recesses or elevations.
Another preferred embodiment of the switching device is characterized in that at least two second metal contact elements are arranged parallel to at least two first metal contact elements. In this case, a contact element forms a common contact, and the further contact element is a switching contact. The common contacts and the switching contacts of the first two metal contact elements are arranged parallel to the second two metal contact elements in each case. Preferably, a snap-action switching mechanism is each arranged between a pair of two metal contact elements, respectively.
Another preferred embodiment of the switching device is characterized in that said switching device has further arrangements of metal contact elements. Preferably, a snap-action switching mechanism is arranged between two adjacent pairs of at least two metal contact elements.
In this case, metal contact elements can also be switched on both sides by means of two synchronizing snap-action switching mechanisms. In an embodiment of the switching device having a plurality of snap-action switching mechanisms, the latter are preferably synchronized by means of a common actuator.
Another preferred embodiment of the switching device is characterized in that the second or further metal contact elements are electrically insulated from the at least two first metal contact elements and from each other, respectively.
Due to the assembly of the switching device, it is possible to provide an absolutely synchronized switch, wherein an individual switch unit preferably comprises three contact elements comprising a common contact and two switching contacts. It is possible to combine a plurality of switch units into one unit in order to achieve higher reliability.
The second and/or further metal contact elements are electrically contactable from the outside of the housing. For this purpose, the metal contact elements preferably project sufficiently from the bottom of the housing.
Another preferred embodiment of the switching device is characterized in that it has a further metal contact element which can be preferably electrically contacted from the outside of the housing. For each group of two contact elements, i.e. common contact point and switching contact, a further contact element is provided. The further contact element forms a further switching contact. Preferably, the snap-action switching mechanism is provided for the disconnection and/or contacting between the first switching contact and the second switching contact.
The contact elements, at least the first actuator-element as well as the contact part and the tension spring consist of an electrically conductive material, preferably electrically conductable metal, wherein the individual components can be made of different electrically conductive materials. The second actuator-element is not necessarily part of an electrical connection and can thus consist of electrically insulating materials, such as plastics, as well electrically conductive materials such as metals.
A preferred embodiment of the switching device is characterized in that the first actuator-element has a further contact part for the disconnection and/or contacting with the two further switching contacts, wherein the further contact part is pre-stretched against the two further switching contacts.
Preferably, the two contact parts connected to the first actuator-element are electrically insulated from each other.
A preferred embodiment of the switching device is characterized in that the first actuator-element has two components which are mechanically connected to each other. In a preferred embodiment of the switching device, the two components are mechanically connected to each other by means of an insulating element. Due to the mechanical connection of the two components of the first actuator-element, the two components function as a common element, wherein the individual components are electrically insulated from each other.
A preferred embodiment of the switching device is characterized in that the contact part is divided into one or a plurality of spring elements. Preferably, at least two of the spring elements of the contact part are of different lengths. If the contact part is designed with spring elements of different lengths, a redundant design of the contact part is achieved. Due to this design of the contact part, it is ensured at any time that the contact part has a certain electrical contact with the switching contacts when it is in the region of the latter.
A preferred embodiment of the switching device is characterized in that at their ends abutting on the switching contacts, the spring elements each have at least one switching contact point projecting from the spring elements. The switching contact points of the spring elements form the electrical connection to the switching contacts.
Another preferred embodiment of the switching device is characterized in that the switching contacts in the region of the contact regions with the sliding contact points have at least one defined uneven area. By the uneven area, for example in the form of a projection or a recess, the sliding resistance between the contact part and the sliding contact points can be influenced, for example increased or reduced, in a defined manner.
Another preferred embodiment of the switching device is characterized in that the actuator is sealed towards the housing by means of a sealing element. Due to the sealing element, it is ensured that as few contaminants as possible can enter the interior of the housing. In addition, the reduction of noise created by the snap-action switching mechanism is achieved by means of the sealing element. Switching devices with snap-action switching mechanisms generally generate noise which might be disturbing. Due to a sealing of the housing, noise may be reduced considerably.
Another preferred embodiment of the switching device is characterized in that the housing cover is sealed the housing by means of a sealing element. Preferably, the sealing element is formed in such a manner that it seals the housing and the housing cover circumferentially. By sealing the connection between the housing and the housing cover, a further reduction of disturbing noise is achieved. The housing cover may preferably be connected to the trough-shaped housing by means of a snap-action connection, for example. Alternatively, the housing cover may also be permanently fixed—for example glued or welded—to the housing mechanically. If the housing cover is welded or glued to the housing, the further sealing element can be omitted, provided that it is ensured that the adhesive joint or the weld forms a sufficient sealing.
A preferred embodiment of the switching device is characterized in that the housing is formed in a trough-shaped manner. A trough-shaped housing means that the housing has a bottom from which preferably four side walls extend preferably vertically upwards. In the bottom of the housing, preferably there are apertures through which the metal contact elements are lead through. Preferably, the lead-through apertures are adjusted to the size and shape of the metal contact elements in a form-fit manner. By means of a trough-shaped housing, it is possible to effectively prevent that liquid soldering material may enter the interior of the housing, for example when the switching device is soldered. If a trough-shaped housing with a circumferential sealing element between the housing and the housing cover is used, a particularly tight sealing of the housing is achieved. It is also possible, however, that the housing cover is glued or welded to the housing. In this case, an additional sealing element can still be provided as well, or the additional sealing element can be omitted.
Another preferred embodiment of the switching device is characterized in that due to the design, the snap-action switching mechanism is held in an unpressed position if no pressure is applied to the actuator. The snap-action switching mechanism is in a stable position when the actuator is in an unpressed position. In the pressed position of the actuator, the snap-action switching mechanism is in an unstable position.
Due to the embodiments of the switching device according to the invention described above, it is possible to carry out the switching operation easily and reliably.
Further advantages, features and details of the invention result from the further description, in which an exemplary embodiment is described in detail with reference to the drawings.
a and 3b show various views of the switching device without the housing;
a and 6b show various views of the snap-action switching mechanism of the switching device;
a and 8b show various views of the arrangement of the second actuator-element in the housing of the switching device.
The actuator 3 transmits the pressure to the second actuator-element 11, which thereby pivots downwards at the same time. The second actuator-element 11 is supported on the left inner edge of the housing 2. In the region of the supporting point of the second actuator-element 11, the housing cover 23 has a shank extending from the housing cover 23 into the housing 2. Preferably, the shank 24 projects into the housing 2 to such a depth that in the region of its supporting point, the second actuator-element 11 is prevented from moving upwards undesirably in the vertical direction. The shank 24 leaves sufficient space for the second actuator-element 11 such that the rotary movement for the snapping of the snap-action switching mechanism 9 is still possible. Alternatively, on the inner wall of the housing 2, a sufficiently large dimensioned projection may be provided instead of a shank 24 on the inner wall of the housing 2 in this region, with said projection starting from the housing cover 23 and fulfilling the same function as the shank 24.
Due to the movement of the second actuator-element 11, the tension spring 12 is tensioned, moving the first actuator-element 10 from its stable resting position as soon as the tensile force of the tension spring is great enough. The first actuator-element 10 pivots downwards, with the electrical connection between the common contact element 5 and a contact element 7 being switched over to the further contact element 6. If no pressure is applied to the actuator 3, the snap-action switching mechanism 9 snaps back from its unstable position to its stable resting position illustrated in
a and 3b show various views of the switching device 1 without the housing 2. As can be seen in
The first actuator-element 10 is pivot-mounted with one end at a supporting point at the common contact points 51. In the illustrated embodiment, the supporting point is constructed in the form of a step at the common contact points 51. In this region, the housing cover 23 preferably has a shank which extends into the housing 2 and prevents the first actuator-element 10 from moving too far from the supporting point in the upward direction. Alternatively, this can be achieved by a geometrical design of the common contact points 51, for example in the form of a notch.
In the embodiment of the switching device 1 illustrated in
In further embodiments which are not illustrated, the contact part 81 may have one or a plurality of spring-loaded arms.
At the right-sided end, the contact part 81 has two apertures 815, via which it is attachable to the first actuator-element 10 of the snap-action switching mechanism 9. The contact part 81 can, for example, be permanently connected mechanically to the first actuator-element 10 by means of laser welding, soldering or any other suitable method. At the ends of the spring elements 811, 812 opposite to each other, the latter have switching contact points 813, 814.
Due to the assembly of the contact part 81 having two or more spring elements 811, 812, improved reliability of the switching device is achieved. For some applications, it is, however, sufficient if the contact part 81 has only one spring element.
Due to the arrangement of the spring elements 811, 812, which are of different lengths L1, L2, it is also possible to vary the sliding resistance between the contact part 81 and the switching contacts in a defined manner. For a further increase of the sliding resistance between the switching contacts and the contact part, the switching contacts may be provided with geometrically designed projections, recesses etc., which have to be overcome by the switching contact point/s of the spring elements before a switching operation. Due to such geometrical design of the switching contacts, a defined sliding resistance is adjustable.
a and 6b show various views of the snap-action switching mechanism 9 of the switching device 1.
b also reveals that the tension spring 12 is hooked onto a preferably metal eyelet 105 of a component 103 of the first actuator-element 10. Alternatively, the tension spring 12 may also be hooked onto the further component 104 of the first actuator-element 10. By means of the insulating part 8 illustrated in
a and 8b show various views of the arrangement of the second actuator-element 11 in the housing 2 of the switching device 1.
b also reveals that the two switching contacts 61 and 71 on the inner wall of the housing 2 are mounted in such a way that a part 24 of the inner wall of the housing 2 is arranged between the two switching contacts 61, 71 such that the surface extending from the first switching contact 61 across the inner wall of the housing 2 to the second switching contact 71 is as plane as possible. As a result, the contact part 81 can easily slide between the two switching contacts 61 and/or 71 when first contact part is moved. The inner wall of the housing 2 on the opposite side in the region of the further switching contacts 161 and/or 171 is designed correspondingly. The common contact points 51, at which the first actuator-element 10 is pivoted, are preferably arranged in such a way that they are spaced from the side walls of the housing 2 in order that the first actuator-element 10 may be pivot-mounted thereon. Preferably, the common contact points 51 are, however, laterally spaced from each other at such a distance that there is sufficient space for the actuator 3 to be moved up and down between the common contact points 51.
b show only one embodiment of the switching device having two groups of three contact elements (5, 6, 7 and/or 15, 16, 17). The switching device is, however, not limited to this embodiment. For example, the switching device can have more than two groups of contact elements, respectively. Preferably, a snap-action switching mechanism is arranged between two adjacent groups of contact elements. Preferably, a plurality of snap-action switching mechanisms can be actuated by means of a common actuator such that a synchronous switching operation is carried out for all groups of contact elements.
In the embodiment of the switching device 1 illustrated in
Even though the switching device according to the invention is shown in
In view of the foregoing, it will be seen that several advantages are achieved and attained. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. As various modifications could be made in the constructions and methods herein described and illustrated without departing from the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. The breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102011014765.9 | Mar 2011 | DE | national |
| 102011016945.8 | Apr 2011 | DE | national |
