DE2755861C2 - Typing keyboard - Google Patents

Description

The invention relates to a typing keyboard, the buttons of which each have an approximately spherical cap-shaped arched, have made of electrically conductive and resilient material contact washer, which rests with edge parts on a support surface and from a Actuating element acting perpendicular to this support surface can be pressed in, the contact disk in pressed-in position bridges at least two contacts in an electrically conductive manner and automatically when the pressure is relieved jumps back to its original position.

Such an embodiment can be found in DE-OS 23 06 268 (in particular FIGS. 3 and 14). It this is the keyboard of an electronic calculator. The actuators are thus as Pushbuttons formed which can be displaced into a cover plate covering the entire switch housing are used. The contact disk is designed as a circular disk and lies with its disk edge on one correspondingly designed contact surface, which thus represents the support surface for the contact disk. There this thin contact surface in turn rests directly on the bottom of the switch housing, is the Distance between the housing base and the contact disk or between the housing base and the from the Contact disc overlapped contacts very low.

The invention is based on the object of the buttons of the known keyboard with a mutual Provide triggering.

This object is achieved according to the invention in that at least some buttons for their mutual triggering via a known latch · and Locking rail which has overtravel curves and which can be longitudinally displaced against the action of a return spring connected to one another and each overlapped by a pivoting lever key body which is geeon the Actuating element of the button is supported by a spring which is designed so that when the Swivel lever key body first the contact disc is actuated, while the further switching path in the latching and upper stroke position is taken up by the spring.

The swiveling lever button body makes a sufficiently large for locking and upper stroke triggering Deflection created. By the above defined ι ο Design of the spring arranged between the swiveling lever '.- key body and the actuating element the button is pressed first, which is then in the detent position due to the non-positive effect of the Spring stays on.

The actuating element can be a pushbutton inserted into the button housing, which is preferably Is square and be guided in the button housing with at least two spring tongues can, which in the rest position of the pushbutton reach under corresponding stops of the button housing with locking lugs provided at their ends.

In the drawing, an exemplary embodiment of the invention is shown. It shows

F i g. 1 in plan view and partly in horizontal

cut a section of a typing keyboard, whereby in the right part of the representation of a swivel lever button

body from overview: omitted for reasons of health became;

F i g. 2 shows the representation according to FIG. 1 in front view and partly in cross section;

3 shows a section along the line III-III in FIG. 1 and

F i g. 4 shows a representation according to FIG. 3 with the button switched on.

In corresponding recesses of a base plate 21, pushbuttons 22 are interchangeably inserted, which are connected to one another via a longitudinally displaceable locking rail 23 for their mutual release and are each overlapped by a pivoting lever key body ? A. The latter is pivoted about a pivot point 25 in the base plate 21 and rests with a control lug 32 arranged opposite the pivot point 25 against a latching and overtravel curve 27 of the locking rail 23, which is longitudinally displaceable against the action of a return spring 28. The upward pivoting movement of the pivoting lever key body 24 is limited by a stop cam 26.

Each button 22 is assigned a light-emitting diode 29, which is also replaceable on the base plate 21 is mounted and protrudes into an opening 30 of the pivot lever key body 24.

leather button 22 consists of a one-piece button housing 1, which has a square cross-section has, only open at the top and is equipped with electrical contacts 2, which are in the bottom 3 of the Pushbutton housing 1 are inserted tightly and end in the interior of the pushbutton housing in a relatively large clearance above the floor 3. In In the selected embodiment, four contacts 2 are provided.

A push button 4 can be displaced into the square recess in the top of the button housing 1 used, which carries a spring tongue 5 on at least two opposite sides, which find them as Latches 6 are formed. When the pushbutton 4 is in the rest position (see FIG. 3), the latching lugs 6 reach under corresponding stops 7 of the button housing 1. Since the relatively narrow gap / wipe

Push button 4 and button housing 1 represents the only access to the interior of the button housing can Impurities from the soldering process can only reach the contacts via a labyrinthine path. To guide the spring tongues 5 are 1 guide lugs on the inner walls of the button housing 8 provided.

In the button housing 1 is an approximately spherical cap-shaped arched, made of electrically conductive and resilient material existing contact washer 9 arranged, which in plan approximately the shape of a The outer contour of the contact disk 9 has a cross, the middle part of which is designed in the shape of a spherical cap is essentially formed by four quadrant arcs 10. The contact disk is located with two of its four is Feet 11 on two diagonally opposite electrical contacts 2 and with their other two Feet 11 on pegs 12, which extend over the floor 3 of the button housing 1 and are formed in one piece with the latter. The free ends of the tenons 12 together with the two contacts 2 arranged in the other corners of the button housing for the contact disk 9 a support surface 13, which the contact disk 9 in a relatively large distance from the bottom 3 The contact disk 9 rests loosely on this support surface, but its position is through the guide lugs 8 centered, which are rounded towards the interior of the switch housing and therefore when Inserting the contact disc act as adjusting lugs. The contact disk 9 is on its underside with four Contact lugs 14 provided. In the illustrated embodiment, it is indeed a question of one On-switch in the form of a pulse button, but it can be seen that the new switch has numerous circuits allows

The pivoting lever key body 24 is supported against the pushbutton 4 via a leaf spring 31, the so is designed that when the pivot lever key body is acted upon first the contact disc 9 is actuated, while the further switching path in the Latching and overtravel position is taken up by the leaf spring 31.

The construction of the individual buttons 22 is very simple and therefore inexpensive to manufacture. Switch housing 1, stops 7, guide or adjusting lugs 8, pins 12, feet 17 and pin-shaped attachment 19 consist of a single plastic part. From the bottom 3 no impurities such. B. Solder or the like penetrate into the button housing 1. This increases the protection from the top improved that each button of the pivot lever key body 24 is overlapped, ap.d that the Contact disk 9 or the electrical contacts 2 at a relatively large clear distance from Bottom 3 of the button housing.

Each button 22 is completely independent of the light-emitting diode 29 assigned to it, which is thus when it is replaced a button can remain mounted on the base plate 21 and vice versa.

For this purpose 3 sheets of drawings

Claims (2)

Patent claims: 1. Touch keyboard, the buttons of which each have an approximately spherical cap-shaped arched, from electrical have conductive and resilient material existing contact washer that has edge parts rests on a support surface and by an actuating element acting perpendicular to this support surface can be pressed in, the contact disk in the pressed-in position having at least two contacts electrically conductive bridged and automatically jumps back into its starting position when the pressure is released, characterized in that at least some buttons (22) for their mutual triggering via a known, detent and upper lift curves (27) and against the action of a Return spring (28) longitudinally displaceable locking rail (23) connected to one another and by one each Swivel lever key body (24) are overlapped, which is against the actuating element (4) of the Button »(22) is supported by a spring (3!) Which is so is designed that when the swiveling lever key body is acted upon, the contact disc is initially applied (9) is actuated while the further switching path into the latching and overstroke position by the spring (31) is recorded. 2. Typing keyboard according to claim 1, characterized in that the actuating element (4) one in the Pushbutton housing (1) is inserted pushbutton