EP1215696A2 - Keypad assembly for an electrical device - Google Patents

Abstract

There is at least one keyboard pad (12) with one or more operating elements (16,28), protruding on an operating side (14) of the pad. On the contact side (44), away from the operating side, are located conductive contacts (46).The operating element is displaceable from its rest to a contact position by directional pressure. In the contact position two allocated contacts (50,52) of an electronic circuit (48) are connectable via the contacts, which comprise contact body of conductive elastically deforming material, separately allocated to respective operating element. An Independent claim is included for the mobile electronic appts.

Description

The present invention relates to a keyboard arrangement for an electronic device, especially for a mobile electronic device, such as a mobile radio terminal, comprising at least one keyboard mat with at least an operating element, the at least one operating element on an actuation side of the at least protrudes a keyboard mat and wherein the at least one Operating element on one side facing away from the actuation side Provide contact side with electrically conductive contact means is, further the control element when pressurized relocatable from a rest position to a contact position in which at least two electrical ones assigned to it Contacts of an electronic circuit via the contact means are electrically connectable or connected.

Such a keyboard arrangement is from the prior art known. For a more detailed explanation of this prior art reference is made to FIG. 6, which corresponds to JP 100 120 88-A. 6 shows a keyboard arrangement 210 according to the State of the art shown. This keyboard assembly 210 is constructed in a modular manner and comprises a keyboard mat 212 which key elements 214 are formed. The keyboard mat 212 is glued to a polycarbonate film 216, this polycarbonate film 216 in the area of the key elements 214 of the keyboard mat dome-shaped elevations 218 has, which are embossed in the polycarbonate film 216. On the side of the polycarbonate film facing away from the keyboard mat 212 216 is a spacer plate 220 with openings arranged in the area of the domes 218. Starting from this is the keyboard assembly 210 over a link layer 222 connected to a circuit board 224, which mechanically is reinforced by a reinforcing plate 226. at Pressurizing the key element 214 according to the arrow P in Figure 6, the key element is down on the top the calotte 218 assigned to this moves and exercises Pressure on this calotte 218. Under the influence of this The calotte 218 also bends pressure force from it in FIG Starting position shown in solid line in a in Figure 6 shown with dashed line and designated 218 ' Deflected. The polycarbonate film 216 is on at least on their side facing away from the keyboard mat 212 in the area of the domes 218 with a contact lacquer, for example from a graphite-silver mixture or the like, Mistake. In the deflected position 218 'touches the Contact surface provided on the dome of the circuit board and can therefore have two contacts running on the circuit board Connect 228a and 228b electrically. After cancellation the pressurization moves the key element 214 back to the starting position shown in FIG. 6. As well the calotte 218 moves out of the deflected position in accordance with 218 'back to the starting position. This will make the electrical Connection between the two contacts 228a and 228b canceled again.

Such a sandwich-like keyboard arrangement according to the prior art of Figure 6, however, shows considerable Disadvantages. Due to the modular structure of several Layers, namely keyboard mat 212, PC film 216 and Spacer plate 220 is the manufacture of the keyboard assembly 210 relatively complex and costly, in particular also because the PC film at least in sections is also to be provided with the contact lacquer. replaces the PC film 216 through a metal calotte provided Plate, to thereby improve the operational reliability, increase the cost of manufacturing the keyboard assembly according to the prior art. Furthermore is subject to the keyboard arrangement 210 shown in FIG the prior art the problem that by the deflection of calottes on the PCB 224 only very small geometric distances for the production of an electrical Connection bridged between the two contacts 228a and 228b can be. Therefore, it is necessary in the manufacturing process circuit board 224 techniques and materials use an arrangement of different conductor tracks or various contacts with a very small distance, even for mass production allow. To ensure this, it is necessary costly manufacturing process for the PCBs or valuable materials for the conductor tracks, such as gold. This increases the Manufacturing costs of one with the keyboard arrangement according to FIG 6 additionally trained electronic device. Because of making the electrical connection small contacts required between contacts 228a and 228b Dimensioning creates the further problem that the keyboard layout and the circuit board assigned to this opposite external influences, especially pollution, very much becomes sensitive. Is stored, for example, in the area of Contacts 228a, 228b dust off, so there is sufficient contact no longer guaranteed by the deflected calotte 218 '.

In contrast, it is an object of the present invention to To provide a keyboard arrangement of the type described in the introduction, which with simple and inexpensive production in Connection with inexpensive printed circuit boards more conventional Construction a reliable and compared to external Insensitive operation guaranteed.

This task is accomplished through a keyboard layout for a electronic device, in particular for a mobile electronic device, such as a mobile radio terminal, solved, comprising at least one keyboard mat at least one control element, the at least one Control element on an actuation side of the at least protrudes a keyboard mat and at least that an operating element on a side facing away from the actuation side Contact side with electrically conductive contact means is provided, further the control element when pressurized from a rest position to a contact position is shiftable, in which at least two assigned to it electrical contacts of an electronic circuit the contact means can be connected or connected in an electrically conductive manner are, and with the keyboard arrangement according to the invention it is also provided that the contact means one respective control element separately assigned contact body made of electrically conductive, elastically deformable material include.

Modular instead of the sandwich keyboard layout to set up, as above with reference to Figure 6 to the stand described the technology, the invention provides that the keyboard mat in the area of the at least one control element on their contact side with a contact body provided electrically conductive, elastically deformable material is. This makes it possible to be proportionate large area an electrical connection between two electrical Contacts of an electronic circuit, for example on the circuit board to connect electrically and this with a simple construction of the keyboard arrangement, since this is only the keyboard mat and trained on it Contact body includes. Furthermore, a reliable one and against deposition of dust or dirt particles on the circuit board insensitive functioning of the keyboard arrangement guaranteed. For example, imagine before that - as at the beginning with reference to the status of Technology described - in the field of electrical to be connected Contacts of the electronic circuit deposits dust, the contact body presses on the dust particles, deformed but because of its elasticity under the Pressurization by means of the control element in such a way that despite the dust particles, the electrical to be connected Touched contacts and thus for an electrically conductive Connection provides. The possibility of using the invention also bridging larger distances electrically conductive, improved also the cost situation with regard to the used Printed circuit boards, as they are now conventional printed circuit boards can be used with standard techniques and less cost-intensive materials, such as with graphite conductor tracks, can be produced. With the invention Solution it is possible to use electrical contacts or Conductor tracks at a distance of up to 6 mm on the Printed circuit board are arranged by an appropriately dimensioned To connect contact body electrically conductive.

With regard to the choice of material for the contact body according to the invention be provided that this from an electrical conductive elastic plastic material, preferably made of an electrically conductive soft elastic rubber material, especially made of electrically conductive silicone material, is made. Such a choice of materials ensures reliable functioning of the keyboard arrangement with a long Lifespan. In addition, the materials mentioned Available inexpensively and in production without the need special arrangements easy to handle.

In the foregoing there have already been indications of a possible dimensioning given the contact body. With regard to the geometric Shape of the contact body can be provided according to the invention be that it is essentially cylindrical or bulbous Shape, preferably essentially circular cylindrical Form, has and with one of its bases on the contact side of the control element is set. He can too include conical sections to facilitate assembly. The contact body is then put together when pressure is applied pressed on the electronic circuit with the control element, this can deform accordingly, whereby - as already stated above - the elastic material any existing dust particles evades and where the contact surface accordingly under pressure increased.

In a further development of the keyboard arrangement according to the invention can be provided that the at least one control element is integrally formed on the keyboard mat. The formation of the at least one control element integral on the keyboard mat allows the keyboard layout to produce as a single assembly, whereby the further Assembly of the keyboard arrangement or the one provided with it electronic device is simplified.

It can further be provided according to the invention that at least an operating element via a resilient connection area is connected to the keyboard mat, at least a control when pressurized under elastic deformation of the connection area against one Spring force can be shifted from the rest position to the contact position and when the pressure is released automatically moved back to the rest position. Such Keyboard mat design is compared to that in relation prior art described at the outset in FIG. 6 in particular necessary because the spring action of the deflected Dome no longer in the present invention is available. The restoring effect can, for example, according to the invention can be achieved in that the resilient connection area is formed with a small wall thickness and itself starting from the keyboard mat to the control element narrows. With such a design of the keyboard mat only the resilient is deformed under pressure Connection area, so that a targeted shift between Rest position and contact position can be achieved. The keyboard mat is advantageously made of soft elastic Material, preferably made of rubber, especially silicone manufactured. This choice of material ensures at low Material and manufacturing costs a reliable function and good haptic properties of the controls of the keyboard mat. This is particularly the case if at least an operating element executed as a push button is.

In a development of the invention it can be provided that the keyboard mat a plurality of grouped Controls includes and that this plurality of controls a common key element is assigned, the key element being able to tumble when pressurized or / and can be depressed and when pressurized the common key element at least one of these assigned control element from the rest position in the contact position is shiftable. Such a staggering movable or / and depressable button element allows easy operation of complex electronic menu structures Contraption. This is the case, for example, with mobile radio terminals required, which with increasingly comprehensive functions be equipped with hierarchical menu structures are selectable. The invention is particularly suitable for a reliable constructive realization of such Key elements with little manufacturing effort and low manufacturing costs. It has to do with a key element assigned to several operating elements namely shown that precisely because of increasing miniaturization corresponding electronic devices problems can occur due to the constructive design of the Keyboard arrangement according to the prior art, as at the beginning explained with reference to Figure 6. by virtue of the considerably simplified structure of the keyboard arrangement according to the present invention, these problems can be overcome be cleared out and there can be several controls commonly assigned key element without loss of function further miniaturized together with the electronic device become.

For example, if the key element mentioned above is used as a so-called navigation key with which navigation in four or possibly eight in regular Angular distances possible over 360 ° distributed directions should be provided in a further development of the invention be that the button element four controls are assigned, with the four controls in the area the corner points of one inscribed in the contour of the key element Square are arranged. Ergonomic operation and gives an attractive visual appearance in this variant of the invention, for example, if the key element has a substantially circular contour.

To the additional key element safely and against unwanted Arrange to be protected on the keyboard mat, can be further provided according to the invention that each of the controls assigned to the key element Has shaft section and that the key element corresponding Has recesses for storing the key element on the controls assigned to it take up one shaft section each. To also for the key element Achieving good haptic properties can be achieved according to the invention further be provided that the key element made of a rubber material, preferably silicone or / and preferably with higher hardness than the keyboard mat or / and the contact body is made.

The invention further relates to an electronic device, especially a mobile electronic device, such as a mobile radio terminal comprising a keyboard arrangement according to one of the preceding claims.

Figur 1

eine perspektivische Ansicht einer erfindungsgemäßen Tastaturanordnung;

Figur 2

eine Draufsicht der Tastaturanordnung gemäß Figur 1;

Figur 3

eine perspektivische Ansicht der Tastaturanordnung gemäß Figur 1, wobei jedoch ein zusätzliches Tastenelement weggelassen wurde;

Figur 4

eine Schnittdarstellung gemäß der Schnittlinie IV-IV aus Figur 2;

Figur 5

eine Vergrößerung des in Figur 4 mit V bezeichneten Bildausschnitts und

Figur 6

eine Teilschnittdarstellung durch eine herkömmliche Tastaturanordnung nach dem Stand der Technik.

An exemplary embodiment of the present invention is explained below with reference to the accompanying figures. They represent:

Figure 1

a perspective view of a keyboard assembly according to the invention;

Figure 2

a plan view of the keyboard arrangement of Figure 1;

Figure 3

a perspective view of the keyboard assembly of Figure 1, but an additional key element has been omitted;

Figure 4

a sectional view along the section line IV-IV of Figure 2;

Figure 5

an enlargement of the image section labeled V in FIG. 4 and

Figure 6

a partial sectional view through a conventional keyboard arrangement according to the prior art.

A keyboard arrangement according to the invention is general in FIG designated 10. This is for installation in a Electronic device, not shown, in the example Mobile radio terminal, provided and includes a keyboard mat 12. From the keyboard mat 12, in particular from its actuation side 14 jump out of several operating elements 16, which are designed as push buttons. Furthermore, the Keyboard arrangement 10 a key element 18, which around the in Figure 2 shown tilt axes A and B in a total of four tilt directions is tiltable. In the middle right in Figure 1 A region 20 is provided in the area of the keyboard arrangement 10 with a central opening 22 into which a microphone can be used. There are also 12 recesses in the keyboard mat 24 in the immediate vicinity of the enclosure 20 and notches 26 are provided which are used to determine the Keyboard mat 12 in the electronic device, not shown serve. The keyboard mat 12 is made of a soft elastic Made of silicone material, the push buttons 16 are integrally formed with the keyboard mat 12.

In Figure 3, the keyboard mat 12 is omitted the key element 18 shown. This figure shows that the key element 18 is mounted on four operating elements 28 is. Each control element 28 comprises a pin-shaped Shank 30, a substantially circular cylindrical Flange 32 and a conical connection area 34, about which the control element 28 with the keyboard mat 12th connected is.

The exact structure and functionality of the controls 16 and 28 is exemplified below with reference to Figures 4 and 5 described for an operating element 28. The 4 shows a sectional view along the section line IV-IV from FIG. 2 shows the keyboard arrangement according to the invention including the tumbling movable key element 18. This is on the four controls arranged at the corner points of a square 28 in parallel to the actuating side 14 of the Keyboard assembly 10 is not slidably mounted. For this purpose, the key element 18 has recesses 36 in which each insert a shaft 30 of an operating element 28 is. For easier insertion of the controls 28 in the recesses 36 during assembly are the controls 28 at their ends 38 remote from the keyboard mats conical. The key element 18 lies with his Bottom 40 on a step surface 42 of each control 28 on, the step surface 42 from the transition from the shaft 30 to the flange 32.

FIG. 5 also shows how the connection area 34 connects the control element 28 to the keyboard mat 12. The connection area 34 can also be seen from FIG. 3 frustoconical with a small wall thickness. On the contact side facing away from the actuation side 14 44 is a pill-shaped one below each control Contact body 46 formed. This contact body 46 is made made of conductive silicone with low (Shore A) hardness. The contact body 46 is on the contact side 44 of the keyboard mat 12 fixed in the area of the control elements 28 by gluing. For example, one presses the button element 18 accordingly Arrow P according to Figure 5, so the control element from its rest position shown in FIG Deformation of the connection area 34 in a contact position relocated. The is in this contact position Contact body 46 in mutual contact with one in FIG. 5 Dashed circuit board 48, on which one electronic circuit is realized. With mutual mechanical Contact between circuit board 48 and contact body 46 bridges the distance between two electrical, on the PCB implemented contacts 50 and 52 and thus ensures for an electrical connection of these contacts. Will the Pressurization released according to arrow P, d. H. if the key element 18 is released again, it is moved this automatically by reshaping the connection area 34 in its starting position, the contact body 46 stands out from the circuit board 48 and the control element 28 together with contact body 46 in that shown in Figure 5 Return to rest position.

The invention shows, compared to the state shown in Figure 6 der Technik, a highly simplified keyboard arrangement, which is inexpensive to manufacture and high functional reliability offers. If you put yourself under renewed attraction of Figure 5 before the case that in the area of the two contacts 50, 52 of the circuit board 48 dust deposits are present, so the invention enables despite these dust deposits a secure electrical connection of the two contacts 50, 52, since the contact body 46 is under pressure according to arrow P due to its soft elastic material properties deformed and thus evade deposits and for reliable contact of contacts 50 and 52 can worry. Two adjacent controls can also be used 28, as shown in Figure 5, in close proximity to each other arrange without affecting their operation would be. This is a further miniaturization of the Keyboard layout according to a required miniaturization the associated electronic device possible. In addition, the invention can be proportionately based on the simple constructive design that is inexpensive available materials for realizing the invention and the favorable properties with regard to contacting of PCB contacts considerable savings in the manufacture of the keyboard arrangement according to the invention and achieve when using corresponding circuit boards.

Claims (14)

Keyboard arrangement (10) for an electronic device, in particular for a mobile electronic device, such as a mobile radio terminal, comprising at least one keyboard mat (12) with at least one operating element (16, 28), the at least one operating element (16, 28) on an actuating side (14) protrudes from the at least one keyboard mat (12) and the at least one operating element (16, 28) is provided with electrically conductive contact means (46) on a contact side (44) facing away from the actuating side (14), wherein further the operating element (16, 28) can be shifted from a rest position into a contact position when pressure is applied (P), in which at least two electrical contacts (50, 52) of an electronic circuit (48) associated therewith can be electrically conductively connected via the contact means (46) or are connected,
characterized in that the contact means (46) comprise a contact body (46) of electrically conductive, elastically deformable material which is separately assigned to the respective operating element (16, 28). Keyboard arrangement (10) according to claim 1,
characterized in that the contact body (46) is made from an electrically conductive elastic plastic material, preferably from an electrically conductive soft elastic rubber material, in particular from electrically conductive silicone material. Keyboard arrangement (10) according to claim 1 or 2,
characterized in that the contact body (46) has an essentially cylindrical or bulbous shape, preferably an essentially circular-cylindrical shape, and is fixed with one of its base areas on the contact side (44) of the operating element (16, 28). Keyboard arrangement (10) according to one of the preceding claims, characterized in that the at least one operating element (16, 28) is integrally formed on the keyboard mat (12). Keyboard arrangement (10) according to one of the preceding claims, characterized in that the at least one operating element (16, 28) is connected to the keyboard mat (12) via a resilient connecting area (34), the at least one operating element (16, 28) being connected Pressurization (P) with elastic deformation of the connecting area (34) against a spring force can be shifted from the rest position into the contact position and automatically moves back to the rest position when the pressurization (P) is released. Keyboard arrangement (10) according to Claim 5,
characterized in that the resilient connection area (34) is designed with a small wall thickness and narrows starting from the keyboard mat (12) to the operating element (16, 28). Keyboard arrangement (10) according to one of the preceding claims, characterized in that the keyboard mat (12) is made of soft-elastic material, preferably of rubber, in particular of silicone. Keyboard arrangement (10) according to one of the preceding claims, characterized in that the at least one operating element is designed as a push button (16). Keyboard arrangement (10) according to one of the preceding claims, characterized in that the keyboard mat (12) comprises a plurality of operating elements (28) arranged in groups and in that a plurality of operating elements (28) is assigned a common key element (18), the key element ( 18) can be moved or / and depressed when pressurized (P) and, when pressurized (P) the common key element (18), at least one control element (28) associated therewith can be shifted from the rest position into the contact position. Keyboard arrangement (10) according to claim 9,
characterized in that four control elements (28) are assigned to the key element (18), the four control elements (28) being arranged in the region of the corner points of a square inscribed in the contour of the key element (18). Keyboard arrangement (10) according to claim 9 or 10,
characterized in that the key element (18) has an essentially circular contour. Keyboard arrangement (10) according to one of claims 9 - 11,
characterized in that each of the operating elements (28) assigned to the key element (18) has a shaft section (30) and that the key element (18) has corresponding recesses (36) which are used to mount the key element (18) on the operating elements () 28) each take up one shaft section (30). Keyboard arrangement (10) according to one of claims 9 - 12,
characterized in that the key element (18) is made of a rubber material, preferably of silicone or / and preferably with a higher hardness than the keyboard mat (12) or / and the contact body (46). Electronic device, in particular mobile electronic Device, such as a mobile terminal, comprising a keyboard arrangement (10) according to one of the preceding Expectations.

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