DE9410529U1 - Keyboard for a computer - Google Patents

Description

Keyboard for a computer

The invention relates to a computer keyboard and, in particular, to a circuit arrangement of a computer keyboard. 5

A computer or a computer system is basically provided with a keyboard for inputting signals. Figure shows a construction of a computer keyboard which is provided with a key unit A, a circuit board B, a rubber pad C, a silver lattice D, a frame E, and a base tray F. The silver lattice D is mounted on the frame E, is covered by the rubber pad C, and has circuits and electrical contacts. The rubber pad C is provided with electrically conductive cones Cl, which are respectively arranged over the contacts of the silver lattice D. The silver lattice D is further provided with a projecting strip Dl, which in turn has contacts which are connected to the circuits of the silver lattice D. The contacts of the projecting strips Dl are respectively connected to the respective contacts on the circuit board B. When a key is pressed, the corresponding rubber cone Cl is compressed to contact the corresponding contact on the silver grid D, causing the circuit board B to output a corresponding signal to the computer for further processing. The connection between the contacts of the circuit board and the contacts on the projecting strip Dl is made by means of a connector Bl which is mounted on the circuit board B. The arrangement of the connector Bl greatly increases the cost of the keyboard. In addition, the silver grid D is easily displaced because it is supported on the frame E.

The invention solves the problem of creating a computer keyboard in which the above disadvantages are eliminated. It is therefore an object of the invention to create a computer keyboard which can be manufactured inexpensively. It is a further object of the invention to create a computer keyboard

which is stable and can be used permanently.

This is achieved according to the invention by the features in claim 1. An advantageous development of the invention is claimed in claim 2.

According to one aspect of the invention, the keyboard comprises a rubber pad provided with conductive rubber cones and a recessed portion, and is further provided with a key unit comprising keys respectively disposed above the rubber cones and an upper silver lattice and a lower silver lattice, these two lattices being vertically separated from each other by a signal insulating plate and held between a frame and a rubber pad, each comprising a protruding strip with respective electrical contacts projecting into the recessed portion, and a circuit board mounted inside the recessed portion to hold the protruding strips of the upper and lower silver lattices down, and the circuit board having electrical contacts on its underside arranged to be in electrically conductive contact with the respective contacts on the protruding strips of the upper and lower silver lattices. According to another aspect of the invention, a rubber pad is mounted on the frame to hold the projecting strips of the silver lattice in place, whereby the upper and lower silver lattice do not shift.

The invention is explained below using preferred embodiments with reference to the drawing. The drawing shows:

Figure 1 is an exploded view of a computer keyboard according to a first embodiment;

Figure 2 is a sectional view of the computer keyboard shown in Figure 1;

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Figure 3 is an exploded view of an alternative embodiment; and

Figure 4 is an exploded view of a conventional computer keyboard.
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As shown in Figures 1 and 2, there is shown a computer keyboard which includes a rubber pad 1, a circuit board 2, an upper silver grid 3, a lower silver grid 4, a signal isolation plate 5, a frame E and a base pan F. The upper and lower silver grids 3 and 4 are disposed between the frame E and the rubber pad 1 and have respective circuits and contacts. The contacts of the upper and lower silver grids 3 and 4 are each disposed in line with respective conductive rubber cones 11 on the rubber pad 1. The upper and lower silver grids 3 and 4 have a projecting strip 30 and 40, respectively, with respective contacts 31 and 41, respectively, which are in electrically conductive contact with the circuit board 2. When one of the keys (not shown) is pressed, the respective rubber cone 11 is pressed into contact with the respective contacts 31 and 41 of the upper and lower silver grids 3 and 4, respectively, causing the circuit board 2 to transmit a corresponding signal to the computer. The rubber pad 11 has a recessed portion 10 and an elongated groove 101 along the inside of the recessed portion 10. The upper silver grid 3 and the lower silver grid 4 are stacked and insulated from each other by the signal insulating plate 5. The projecting strips 30 and 40 of the upper and lower silver grids 3 and 4 are respectively inserted through the elongated grooves 101 and overlap each other inside the recess part 10. However, the contacts 31 on the upper silver grid 3 and the contacts 41 on the lower silver grid 4 are formed so that they are separated from each other when the projecting strips 30 and 40 overlap each other inside the recess part 10. The circuit board 2 has contacts (not shown) on its underside.

When the circuit board 2 is firmly mounted inside the recessed part 10 of the rubber pad 1, the contacts of the circuit board 2 are arranged in contact with the contacts 31 and 41 of the upper and lower silver grids 3 and 4, respectively. Because the upper and lower silver grids 3 and 4 are covered by the rubber pad (see Figure 2), they are firmly held in place when the circuit board 2 is firmly attached to the rubber pad 1.

Figure 3 shows an alternative embodiment in which a small rubber pad 6 is mounted on the frame E to support the overlapping projecting strips 30 and 40 on the upper and lower silver grids 3 and 4, respectively. In this alternative embodiment, the rubber pad 1 has a notch (instead of the recess part 10) into which the overlapping projecting strips 30 and 40 extend. The circuit board 2 covers the projecting strips 30 and 40 and is firmly attached to the rubber pad 6.

In summary, a keyboard for a computer is thus created, which is provided with: the rubber pad 1 with the conductive rubber cones 11 and the recess part 10, the key unit with the keys arranged above the rubber cones 11, the upper and lower silver latticework 3 and 4, respectively, which are kept at a distance from each other in the vertical direction by means of the signal insulating plate 5 and are held between the frame E and the rubber pad 1 and have the respective projecting strips 30 and 40, respectively, and whose respective electrical contacts 31 and 41 protrude into the recess part 10; the circuit board 2, which is mounted inside the recess part 10 to hold the projecting strips of the upper and lower silver grids 3 and 4 down and have electrical contacts on the underside thereof which are in electrical contact with the respective electrical contacts 31 and 41 of the projecting strips 30 and 40 of the upper and lower silver grids 3 and 4.

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Claims (2)

Expectations 1. Keyboard for a computer, with a rubber cushion (1) which is supported on a frame (E) above a base pan (F) and has a plurality of electrically conductive rubber cones (11), a circuit board (2), a silver latticework arrangement which is held between the rubber cushion (1) and the frame (E), a key unit which covers the rubber cushion (1) and has a plurality of keys which are each arranged above the rubber cones (11) and can be selectively pressed down in order to trigger the circuit board (2) by means of the silver latticework arrangement and thus cause the circuit board (2) to generate a corresponding signal and transmit it to the computer, wherein the rubber cushion (1) has a recessed part (10) and an elongated groove (101) extending along one side of the recessed part (10); the silver lattice assembly has an upper and a lower silver lattice (3, 4), the upper silver lattice covering the lower silver lattice, and has a signal insulating plate (5) which is arranged between the lower and upper silver lattice and is thus covered by the upper silver lattice (3), the lower silver lattice (4) having a projecting strip (40) which is inserted through the elongated groove (101) into the interior of the recess part (10) and is thus arranged therein, while the upper silver lattice (3) also has a projecting strip (30) which is inserted through the elongated groove (101) into the recess part (10) and covers a part of the projecting strip (40) of the lower silver lattice (4), the projecting strips (40 resp. 30) of the lower or upper silver latticework (4 or 3) have respective electrical contacts (41 or 31) arranged at different locations at a distance from one another; the circuit board (2) is firmly mounted inside the recessed text (10) and the projecting strips (30 or 40) of the upper or lower Silver latticework (3 or 4) and has a plurality of electrical contacts on its underside, which are in respective contact with the electrical contacts (31 or 41) of the projecting strips (30 or 40) of the upper or lower silver latticework (3 or 4). 2. A keyboard according to claim 1, further comprising a rubber pad (6) mounted on the frame (E) to hold the projecting strips (30 and 40, respectively) of the upper and lower silver latticework (3 and 4, respectively) in place.