The present invention relates to an integrated switch or an integrated button for component parts which are provided with a preferably flexible surface covering.
In particular in the automotive sector the trend nowadays is heading ever more in the direction of buttons and switches being integrated directly in the interior and therefore being as unobtrusive as possible. Most interior surfaces in an automobile are, in addition to plastic, so-called natural materials such as leather or textile, i.e. supports or housings providing the structure in the case of these surfaces are provided with a surface covering made from a soft and/or flexible material.
It is easily possible to position a button behind a leather or textile surface and therefore to integrate the switching function directly in the surface. Symbols can be, for example, printed on or adhesively bonded on in such situations.
What is nowadays lacking are buttons which are integrated, for example, directly in the surface with backlit symbols which are also visible at night and buttons which can be installed without a considerable amount of complexity in terms of fitting and which protrude slightly beyond the surface covering.
Accordingly, the invention is based inter alia on the object of providing an improved switch or an improved momentary-contact element which, among other things, makes backlighting possible. Furthermore, a method is provided with which such a switch can be installed in a cost-effective and resistant manner. What is involved here are switches which perform simple on/off functions, but equally also switches which can perform more complex functions such as those of rockers, navigators in different directions, etc.
The term switch in the context of the present invention is therefore to be understood as meaning a momentary-contact element, which can be triggered by a finger, for example, and which can pass on the pulses desired by the operator to a controller, for example, via a contact mechanism and/or circuit positioned behind it. In this case, it is a question of a switch for at least partially embedding in or on a support, which is coated, at least in the region of the switch, on its surface with a preferably flexible surface material. The support may be a housing part or else a seat cushion or a steering wheel, a shift lever or the like, for example. The flexible surface material, which is provided as the surface covering, can be textile, leather, imitation leather, a plastic layer or a metal layer or combinations thereof.
This is achieved, inter alia, by virtue of the fact that the switch is arranged in a cutout of the surface material, the switch having a first region arranged substantially in (or possibly also on) the support and a second button head provided for manually triggering a function. In this case, the button head covers the cutout in the surface material, at least in regions, on the upper side of the surface material and is connected thereto in a force-fitting and/or form-fitting manner. The term “so as to cover the cutout” is in this case understood to mean that the button head has a contour which is greater than the size of the cutout and therefore the button head with its underside covers the surface of the surface material in the edge region, at least in regions, preferably peripherally.
In accordance with the prior art, such switches are provided with a housing part, in which the actual button head is recessed. In other words, the button head is recessed in a housing which is likewise exposed at least in the edge region toward the surface. This housing part in this case needs to be embedded correspondingly with this edge, which is exposed toward the surface and frames the actual button, in a cutout in the surface material with a very precise fit.
One of the essential aspects of the invention therefore consists in now entirely dispensing with such an exposed edge of a housing and the button head, which is preferably manufactured from a flexible material such as silicone, for example, or a flexible plastic (even thin leather is possible) being adhesively bonded directly to the surface material at the edge, for example. Such a switch correspondingly requires a formation of a cutout in the surface covering which has a substantially less precise fit and can have a more compact design and can be integrated substantially more easily.
In accordance with a first preferred embodiment of the switch, the button head covers the cutout in the surface covering peripherally. Further preferably, it is correspondingly adhesively bonded to the surface material peripherally. In this case, adhesive films, silicone, adhesives or other suitable adhesives can be used.
In accordance with another preferred embodiment, the switch is characterized by the fact that the button head has at least one fastening element, by means of which the button head is fastened in the surface region, which is covered by the underside of the button head, of the surface material to said surface material. In this case, the fastening element can preferably be in the form of a lug (or flexible pin), which makes a form-fitting connection possible by means of being bent back. In other words, in accordance with a preferred embodiment it is possible for the fastening element to be a lug, which engages in an opening in the surface material and wherein either self-latching (for example resilient tongues or else projections which, as a result of the extension of the soft surface material during insertion through the opening, bring about fixed hooking once the material has passed through completely) or by fastening by means of adhesive bonding and/or bending back is possible. The latter, i.e. fastening by means of being bent back, is preferred, in this case the bending-back taking place on the underside of the surface material and, as a result, fastening taking place in a form-fitting and/or force-fitting manner (if, for example, an adhesive is additionally used).
It is preferred if the fastening element is fastened in a form-fitting manner in or on the button head.
A further preferred embodiment is characterized by the fact that a metal frame (peripherally or else partially interrupted) is arranged in or on the button head, at least one fastening element, which, for example, protrudes out of the button head, being fastened and/or integrally formed on said metal frame. The metal frame is preferably arranged in or on the button head so as to be peripheral at least in regions and has a plurality of fastening elements in the form of lugs.
In accordance with a further preferred embodiment, the fastening element and one or more possibly provided metal frames are made from a flexible and/or electrically conductive material, in particular preferably from a metal. The fastening element and the metal frame (or at least segments of the metal frame) are preferably designed to be integral and in particular preferably to be produced in a stamping deformation process.
Such fastening elements and metal frames which may be provided have proven to be particularly useful for making at least indirect contact with a lighting element, which is arranged in the button head. In this case, at least two fastening elements and one metal frame made from an electrically conductive material, in particular preferably from a metal, can be arranged, and the metal frame can comprise two electrically isolated segments, each segment having a fastening element, and in particular preferably the lighting element (for example an LED) is connected with its two electrical terminals to these segments via webs or wires. Very simple production is therefore made possible. That is to say that, for example, the metal frame can be produced together with the fastening elements in a stamping deformation process, and then the lighting element can be fitted thereon (for example by means of soldering). This component part is then inserted into the mold for producing the button head and embedded in the compound of the button head in the production process.
Preferably, the at least one fastening element is in the form of a lug, which lugs pass through openings in the surface material and in addition through openings in further elements, which are arranged therebeneath, for example through openings in a printed circuit board and/or the support and/or in a fastening component part. The lug is then bent back on the side which faces away from the surface material of the entirety of the elements through which it passes.
A further preferred embodiment is characterized by the fact that the switch has a sensor function and a switch function, in this case in particular preferably a printed circuit board, for example in the form of a flexible printed circuit board, being arranged, which printed circuit board, on one side, preferably the upper side, provides the functionality for the sensor function and, on the other side, preferably the underside, provides the switch function, with a further tactile element preferably being arranged on the underside for this purpose.
Another preferred embodiment is characterized by the fact that a large number of tactile elements is arranged beneath the button head, it being possible for these tactile elements to be arranged in a row and/or in a circle and/or a semicircle or in a combination thereof.
A further preferred embodiment of the switch is characterized by the fact that the first region has at least one tactile element, which produces a contact, for example a control pulse in a printed circuit board arranged in the first region (a flex circuit or sensor etc. are also possible, for example), with tactile feedback, on manipulation of the button head.
As already mentioned, such a switch can preferably be provided with backlighting. This is preferably easily possible when the button head is designed to be transparent or at least partially translucent. Depending on the arrangement of the light source, it may prove to be advantageous to produce tactile elements arranged in the first region from a substantially transparent or at least partially translucent material as well, for example when the light source is arranged in the first region behind the tactile elements. It is possible to design regions on or in the button head to be impervious to light so as to form backlit symbols, for example by a light-impervious coating being provided on (or beneath) the button head, which coating has reliefs in the form of symbols or characters.
In accordance with a further preferred embodiment, the support may be a component part in the interior of a vehicle, in particular inner cladding, a steering wheel, a gearshift, a car seat or the like.
As already mentioned, the button head is preferably a flexible element, which protrudes beyond the surface of the surface covering at least in the edge region, in which the surface covering is covered. The button head can have, for example, a convex surface, which, in rounded-off form, protrudes beyond the surface of the flexible surface material and merges with the surface material, for example forming a sharp edge or else with a sliding edge.
As already mentioned, the cutout in the surface material is smaller than the surface cross section of the button head, with the result that the button head covers the surface material peripherally in the edge region. In this case, the coverage is preferably overall at least in the range of from 0.5-10 mm, in particular preferably in the range of 2-3 mm. The first region is preferably also arranged at least in regions in the edge region behind the cutout, i.e. it is preferably covered peripherally by the cutout in the surface material.
Another preferred embodiment of the switch according to the invention is characterized by the fact that a recess, for example with a depth in the range, of 1-20 mm, preferably of 3-8 mm, is provided in the support. A printed circuit board, a flex circuit or a sensor is provided as a component part of the switch on the bottom of this recess, and these elements can be adhesively bonded on the bottom of the recess, for example with the aid of an adhesive or an adhesive film. A preferably transparent base element, which can likewise be adhesively bonded, is provided on these elements. This base element preferably has a shape which is matched to the shape of the recess and can comprise, for example, transparent silicone. The base element has either tactile elements as separate component parts or such tactile elements are formed as a component part of the base element, i.e. are designed to be integral with it. Examples of tactile elements are switchpads, metal domes (for example metal dome foil) or polydomes (polydome film), silicone domes. A button head is then arranged on this base element or on the tactile elements and adhesively bonded thereto, preferably the surface material being clamped in between the base element and the button head and/or being adhesively bonded thereto.
As already mentioned, the switch may also be a complex configuration, for example a switch which has at least two different positions or control contacts, which can be manipulated via a single button head. Preferably, the switch has only one single button head.
Furthermore, the present invention relates to inventive uses of such a switch, for example as an individual button, rocker, navigator in different directions (cf. joystick) or two-stage or multistage switch. Preferably, such a switch is used in the interior of a vehicle, for example as a window opener, mirror adjuster, seat adjuster or switch which is integrated in clad instrument panels for car radio/air conditioning/navigation/telephone etc.
Furthermore, the present invention relates to a method for fitting such a switch. In this case, in a first step a support, for example a vehicle seat, is coated with a flexible surface material substantially over the entire area in accordance with the conventional process in this field. In this case it is not important whether the surface material is adhesively bonded to the support over the entire area. In a second step the surface material is cut out or stamped out to the desired size so as to form a cutout, for example in the region of recesses which are preferably provided in the support. In a third step, the switch is then inserted into the recess (with the surface material possibly being temporarily extended in the region of the cutout) and then the flexible button head is adhesively bonded peripherally onto the surface of the surface material in the edge region of the cutout. In this case it is possible to first of all produce the switch in two parts, a first region and the button head. In this case, in the third step first the first region can be inserted through the cutout into the recess and fixed therein, and then the button head can be positioned onto the first region and onto the surface material and fixed thereto, for example adhesively bonded thereto.
Further preferred embodiments of the switch, the uses and the method for fitting are described in the dependent claims.
The invention will be explained in more detail below with reference to exemplary embodiments in connection with the drawings, in which:
Backlit keyboards can be produced using transparent silicone or plastic; this is nowadays already in wide use, for example in combination with a plastic housing. The idea is now to integrate individual backlit silicone buttons directly in a leather, plastic, metal or textile surface. In this case, the button head is fastened on the surface material by means of an adhesive layer, with the result that a tight and fixed connection is provided. The unclean cut edge of the surface material is covered by the button cap. Therebeneath there is then a base element, which is fastened on the underside of the surface material. A tactile element beneath the button cap takes over the switching function and produces the tactile feedback to the operator indicating that the contact is closed. A contact pill closes the electrical contact, for example on the printed circuit board. By means of a light source, the symbols on the button head are backlit through the transparent tactile element and the transparent button head.
The parts are all connected to one another and, as an entire unit, integrated in a support housing or seat cushion.
For illustrative purposes, a few exemplary embodiments of such a switch or such a keyboard will be presented below with the aid of the figures. It should be emphasized here that the exemplary embodiments are only used for illustrative purposes and not for restricting the scope of protection as defined in the patent claims.
The support housing 4 is coated with a layer of a surface material 3. This surface material 3 can be textile, leather, slush or another surface material which covers the component part. The surface material 3 is typically flexible and can have a coating or a three-dimensional structuring on the surface. In the region of the recess 5, a cutout 6 is provided in the surface material, through which cutout the switch 1 passes.
The actual switch 1 comprises a first region, which is arranged predominantly beneath the surface material 3, i.e. on or in the support structure 4. First, a printed circuit board 8 or a flex circuit or a sensor (only referred to as printed circuit board 8 below) is arranged on the bottom of the recess 5. This printed circuit board 8 is connected to a circuit via lines routed in the region of the recess and out of it or is connected directly to the member to be actuated (for example motor for window opener). Conductor tracks (not illustrated), which trigger the actual functionality in the event of actuation of the switch (closing or opening of a control circuit), are provided on the printed circuit board 8.
On the one hand, a base element 7, which is made from transparent silicone, for example, is arranged on this printed circuit board 8. On the other hand, one or more tactile elements 9 are arranged in the central region.
Possible tactile elements used are switching mats, metal domes, polydomes etc. Preferable here are component parts made from at least partially transparent material. This may also be, as illustrated in
The tactile element 9, in precisely the same way as the base element 7, is transparent or at least partially translucent. In addition, a light source 10 for example in the form of an LED is arranged beneath or between the tactile elements 9. The use of an electroluminescent film (see further below) is also possible. The light emitted by this light source 10 can pass through the transparent elements of the first region and therefore to the surface.
Furthermore, the switch 1 comprises a button head 2. This button head 2 is made from a transparent or slightly colored, light-pervious material (plastic, elastomer or silicone). In its edge region, the button head 2 engages over the cutout 6 in the soft surface material 3. The button head 2 is provided, in addition, with a preferably wear-resistant colored layer 14 (single-layered or multilayered) either on its surface, as illustrated in
In order to fasten the switch in the recess 5, the printed circuit board 8 is preferably fixedly bonded on the bottom of the recess 5. The corresponding layers of adhesive 12 are each illustrated by dots in
The base element 7 and the tactile elements 9 are also $ fastened on the printed circuit board 8 using an adhesive layer 12 or an adhesive film. In addition, the base element 7 first can have a light-impervious layer 13 (for example black sprayed-on layer) on the upper side facing the soft surface material 3 in order to ensure that light from the light source 10 does not pass through the surface material 3 in the region thereof which directly adjoins the button head. In addition, the base element 7 can also be adhesively bonded to the underside of the surface material 3. The button head 2 is also adhesively bonded to the first region of the switch 1, i.e. to the tactile elements 9 in the example shown in
In principle it is possible to provide the entire switch 1 in the already completely assembled form and to install it into a recess 5 as a whole. However, it is also possible, as is illustrated in the following
Once the component part has been provided with the covering of the surface material 3 and possibly further working steps have been carried out, a cutout 6 is formed for the installation of the switch at the suitable point, i.e. above the recess 5 but with a smaller cross section than the recess 5. This is illustrated in
A switch, onto which the button head 2 has not yet been positioned, is now inserted into the thus prepared cavity, as is illustrated in
Now only the button head 2 can be positioned from above, as is illustrated in
In this context, it should be emphasized that it is on the one hand possible to manufacture the button head 2 from a rigid material and to a certain extent to ensure the movability by means of the base element 7 and the likewise flexible surface material 3 positioned above this. Preferably, however, the button head 2 is also produced from a soft material such as silicone, for example.
In order to make embedding into the surface material 3 in accordance with the invention possible, this component part has an undercut, into which the surface material 3 is introduced and bonded.
This construction is advantageous in terms of manufacturing technology to the extent that in a single step the element comprising the button head, the base element and the tactile elements can be produced and only the contact elements 11 then need to be adhesively bonded and the printed circuit board positioned in order to produce the switch. On the other hand, this construction does not allow for installation as illustrated in
A further alternative exemplary embodiment is illustrated in
The following variants of the abovedescribed exemplary embodiments are possible and each have specific advantages:
Button Head 2:
Individual button, rocker, navigator in different directions, two-stage switch etc.
Any desired shape: round, circular, oval, angular, polygonal etc.
An individual button or a plurality of buttons next to one another or one above the other, in each case one tactile element or a plurality of tactile elements per button.
Material Used: Plastic, Metal or Silicone.
Connection of button head: bonding to tactile element 9 or to combined part comprising tactile element 9, possibly base element 7, with button head with undercut.
Tactile Element 9:
Silicone switching mat with contact pill, metal dome, polydome or silicone switching mat with plunger on pressure sensor.
Light Source 10:
LED or electroluminescent film (rigid or flexible).
Printed Circuit Board 8:
Standard printed circuit board or flexible printed circuit board (flex circuit) or pressure sensor film.
Surface Material 3:
Leather, textiles, slush, silicone or other flexible materials. Thickness preferably <1 mm, i.e., for example, in the range of 0.01-2 mm, preferably in the range of 0.3-1 mm.
Adhesive Layers 12:
RTV silicone, hot-melt adhesive, adhesive films or direct vulcanization of the surface material 3 in the compression molding die with base element and/or button head.
Light-Impervious Layer 13:
Sprayed onto base element with silicone color or in the form of a film.
Symbols 15:
As night design (lasered), positively or negatively printed.
In general, the following advantages result, inter alia, from the proposed construction:
The following exemplary applications are possible:
In other words, fastening lugs is, which are provided for fastening purposes preferably in holes or slots 24 in the soft surface material 3, are fitted on the button head 2. In this case, they are pushed through these holes or slots 24 for fastening purposes and then bent back at the free end. The fastening lugs 18 are preferably made from a flexible material, in particular preferably from metal. However, they may also be in principle rigid elements, which have, for example, movable (snap-action tabs) or equally rigid retaining tabs (laterally and/or on the front side or the rear side), in the latter case the fastening lugs 18 being inserted into the slots 24 during fitting with a slight reversible extension of said slots 24.
Preferably, in a so-called co-molding process, an appropriately shaped stamped bent part made from metal (which is preferably produced integrally in a stamping and deformation process from a piece of sheet metal, cf.
The lugs can also be fitted as individual lugs in a subsequent adhesive-bonding process to the button head or bonded into blind holes in the button head.
The button head 2 is then inserted into the appropriately sized recess 6 in the base material and the fastening lugs 18 are inserted into holes or slots 24, which are likewise provided in the surface material 3, from above at the same time. Then, the fastening lugs 18 are bent back on the underside of the surface material in such a way that the button head 2 is fastened in or on the surface material 3 in a form-fitting manner. The bent edges can in this case already be impressed or stamped in advance on the metal frame.
Then, the tactile element and the printed circuit board are fastened to the support 4 for example by means of screws 19, rivets or by means of adhesive bonding.
Advantages:
The metal frame 17 with the fastening lugs 18 is plugged through the appropriately shaped cutout 6 in the surface material 3, and the fastening lugs are plugged through the slots 24 and through corresponding recesses in the support 4 and the printed circuit board 8 and are fastened by means of being bent back on the underside of the printed circuit board 8.
This has the enormous advantage that fitting is very simple.
Prior to the co-molding with the button head, a light source (LED) can be soldered to the metal frame, for example in an SMT (surface mount technology) process or by means of wire-bonding. The metal frame in this case needs to be interrupted between the LED terminals in order that contact can be made with the light source via the fastening lugs 18 (which is particularly simple), with the result that there is no short circuit. A corresponding component part prior to it being embedded in a button head 2 is illustrated in
The button head 2 with the integrated light source 10 is then plugged on again and connected to the printed circuit board via the fastening lugs 18. In order to obtain good electrical contact, the fastening lugs 18 are best soldered on the printed circuit board 8 once they have been bent back. The fastening lugs 18 in this case therefore not only serve the purpose of fastening the button head 2, but at the same time also act as contact tracks and terminals for the light source 10. The material for the metal frame 17, or at least of the webs 25, must be flexible in order to be able to go along with the short stroke of the tactile element 9, 11 (in this case in the form of a metal dome 11) in the region of the light source 10. The stroke of the button is in this variant essentially only achieved via the deformation of the flexible button head and at most of the flexible metal frame.
The printed circuit board 8 is preferably in the form of a rigid/flex circuit, and as a result the required rigidity is provided in the region of the tactile element (rigid region); a plurality of buttons can be connected to one another easily by means of the flexible region (not illustrated).
Advantages:
In this variant, the metal dome 11 is arranged on the lower side and the light source 10 is arranged on the upper side of a double-sided flexible printed circuit board 8. The actuation of the metal dome 11 in this case takes place above the head via a silicone actuator 20. The latter is either inserted directly in the support 4 or is fitted on an additional support plate 19. A peripheral relief 21 can be provided in the flexible button head 2 in order to facilitate the stroke action.
Advantages:
Similar to the exemplary embodiment illustrated in
The printed circuit board and the tactile element are inserted into the recess 5 through the cutout in the soft surface material 3. For fitting purposes, fitting holes 23 are provided in the support 4, through which the fastening lugs 18 can be bent back from the underside.
In addition to this there is also an additional sensor function 22, which on slight touching contact with the button head 2 via the peripheral relief 21 results in contact on the upper side of the printed circuit board. The element for the sensor can either be a conventional contact pill, but may also be another type of pressure sensor such as, for example, an FSR (force sensing resistor) or a capacitive sensor. This sensor function can also be incorporated in other variants. In other words, a sensor function (first switching plane) which is already activated given a low force and a switching function (second switching plane) which is only activated in the event of a greater force result.
Advantages:
A further exemplary embodiment is illustrated in
In other words, this refinement discloses the replacement of a conventional rotary knob with a switch which by itself is not capable of moving mechanically in rotary fashion and which is embedded in a soft surface material 3. The tactile incrementation of a rotary knob (for example for the volume control or temperature setting in a car) is replaced by the tactile elements (metal domes) being arranged very close to one another. Thus, this application can also be realized in a very simple and cost-effective manner (without mechanically rotating parts) directly in the surface material 3. Corresponding shaping of the button head can guide the finger through the “rotation”. A coating with a slidable varnish, for example sealplast, is recommended.
As a result of the successively individual switching of the metal domes 11 arranged in a circle, a correct rotary knob feel is produced (or similarly slides if arranged in a linear row, or else semicircular arrangements or any desired characteristics are possible). In the center, a further knob, for example in the form of a selection button, is fitted. Further functions such as LEDs or touch sensors can naturally also be introduced.
Advantages:
Number | Date | Country | Kind |
---|---|---|---|
1793/05 | Nov 2005 | CH | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/CH06/00596 | 10/25/2006 | WO | 00 | 3/18/2009 |