DE8716968U1 - Pushbutton switches especially for keyboards - Google Patents

Description

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Patent attorneys 1 1856.4 Ka/Kr

Wenzel & Kalkoff
PO Box 2448
Flaskuhle 6
5810 Witten/Ruhr

Applicant Wickmann-Werke GmbH

Annenstr. 113 5810 Witten 6

Designation: Push button switch especially for keyboards

The invention relates to a push button switch, in particular for keyboards, comprising a housing in which a push button which can be operated by hand or with a finger for closing or opening the key is arranged.
is arranged so as to be depressible.

Push button to close or open contacts

³ ^ Electrical devices are usually switched on and off by means of a switch that can be operated by hand or with a finger. Certain device functions are also initiated or terminated by means of certain switches. In particular, pushbutton switches, pull switches, rotary switches, toggle switches and slide switches are considered for this purpose. In the following, the present invention is applied to pushbutton switches in the preferred embodiment as a pushbutton switch.

However, from the description of the invention it is clear that the invention can be adapted accordingly

§ Can also be easily implemented on other types of switches

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Electrical devices are protected by electrical fuses

g against load especially in case of short circuit

protects. The installation of a fuse holder

% in the device with appropriate contact

k 10 required. Attempts have already been made to reduce the construction costs for device switches and for device protection by integrating the fuse holder into the switch housing. One such attempt is evident from DE-PS 30 11 853. There, a

% 15 tube fuses are integrated into the housing of a toggle switch in such a way that the current supplied to the device when it is switched on is always passed through the fuse. However, this solution does not lead to a structural simplification but rather to a very complicated switch structure.

Nevertheless, the innovation is based on the task of combining the technical functions of a device switch and a device protection fuse in a common component.

An. simple Heise to summarize.

This task is solved in accordance with the innovation in that a miniature fuse is arranged in the housing of the pushbutton switch below the push button, which is located in the current path that is closed or broken between the inner contacts when switching on or off.

To clarify the invention, it is pointed out that the term "miniature fuse" refers to an electrical fuse which, despite its small dimensions, has a relatively high current loss which is in the range of 35 - 100 ä. The dimensions of a cylindrical fuse are

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gfe housing in the order of 10 hkv for the diameter and 5 - 10 now for the height. This is a preferred embodiment within the scope of the innovation, without the innovation being limited to this. Even tube fuses of the smallest design can be used within the scope of the innovation if they have the appropriate switching capacity.

The innovative solution is characterized above all by the fact that the two functions mentioned above, namely switching on and off on the one hand and electrical protection on the other, are taken over by a new component that can be referred to as a fuse pushbutton or a pushbutton switch with fuse, whereby there is no difference in the size of the previously usual pushbutton switches; because the miniature fuse is arranged inside the existing housing below the pushbutton. The fuse is located there between the contacts - normally there are two contacts - by bridging or separating which an electrical device is switched on or off. The separate fuse holder that was previously necessary is no longer required and the space required for this is saved.

In addition to the elimination of the fuse holder and the space saved, it should also be emphasized that the proposed solution can be implemented without any particular difficulties in terms of construction if one of the following paths is labeled.

Preferably, the miniature fuse is arranged in a switching bridge, by means of which the contacts are electrically connected or separated by pressing a button. This arrangement of the miniature fuse in the switching bridge within the button housing leads to a particularly simple design.

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&khgr; The miniature fuse is conveniently integrated in the housing in a switching bridge for two contacts, which is connected on one side to one of the contacts in an electrically conductive and preferably flexible and spring-loaded manner, and on the other side engages or is separated from the other contact at the push of a button. With this single-pole operation, the miniature fuse forms part of the switching bridge/ over which the current flows when the device is switched on, and thus follows the switching path of the bridge when it is moved by pressing the push button and brought into or out of engagement with the inner contacts.

As an alternative to the above design, the miniature fuse, whose two connection contacts are both connected to a

side of the miniature fuse, must be attached to the push button below the base so that the connection contacts can be integrated into a switching bridge that can be placed on or removed from the contacts using the push button for switching on and off. This involves double contacting of the two inner housing contacts through the switching bridge. This is located on the push button below its base, and the miniature fuse can be easily inserted into this

arrangement, especially since the two connection contacts of the miniature fuse only protrude on one side of it.

With this arrangement of the miniature fuse, a design is particularly advantageous in which the miniature fuse is attached with its contactless top to the bottom of the finger button, so that the connection contacts protruding from the bottom are already located in the area of the switching bridge due to the design of the fuse.

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In this respect, the designer only needs to go one step further to design the miniature fuse itself as a switching bridge and to use its connection contacts for switching on

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and off switches of an electrical device to engage or disengage the internal contacts in the housing.

Examples of the innovation are explained in more detail below with reference to the drawing. In the drawing show;

Fig. 1 is a cross-sectional view of a pushbutton switch with single-pole contacting by a switching bridge;

Fig. 2 a cross-sectional view of a push button switch

with double contact through a switching bridge.

The designs shown in the drawing are to be understood as purely schematic examples, in which structural details play no role.

A housing 1 made of plastic, which can have a cylindrical, square or rectangular shape, has connection contacts 2, 3 on its underside, which extend into the interior of the housing 1 and form internal contacts 4, 5 there.

A switching bridge, generally designated 6, is spring-mounted on the right-hand contact 5 with reference to the drawing in such a _way that the contact bridge 6, when a button is pressed from above, rests with its free contact 7 on the contact 4 and thus closes the current path between the contacts 4, 5.

A miniature fuse S is integrated into the contact bridge 6 in the manner shown, the connecting pins 9, 10 of which protrude from the underside of the miniature fuse 8 and are thus included in the switching bridge 6 which has a carrier 11 made of insulating material.

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• J In the housing 1, a push button 12 is arranged in the usual way, which can be operated with a finger and can be pressed down against the pressure of a spring 13 to switch on and off. Immediately below the base 15 of the push button 12 there is a guide 14, which engages with the upper part of the socket fuse 8 or at least comes into engagement when the push button 12 is pressed down if the switching bridge 6 is to connect the contacts 4, 5.

In this embodiment and also in the embodiment described below , the extraordinarily small space requirement of the subminiature fuse i\ in the housing 1 or below the push button 12 is readily apparent.

In the second embodiment according to Figure 2, the basic structure is the same as in the previously described example, so that only the differences between the two examples need to be pointed out.

The inner contacts 4, 5 each end as contact contacts which are connected to one another when the switch bridge 6 with its two free contacts is placed on the contacts 4, 5 by pressing down the push button 12, thereby creating a current path between these contacts. In contrast to the first example, the miniature fuse 8 is attached with its contactless top to the base 15 of the push button 12, and its connecting pins 9, 10 protruding from the bottom, together with a carrier 11 made of insulating material, form the switch bridge 6, including the miniature fuse 8 itself.

While in the first example the miniature fuse 8 is integrated into the switching bridge 6 on the housing side, in the second example it forms the essential component of a pushbutton-side switching bridge. A single

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The one-pole actuation in the first example is contrasted with a two-pole contact in the second example.

Due to the high switching capacity of the fuse, the new component, two examples of which are described above, serves as a device protection element and a power switch at the same time.

It goes without saying that the new key switch can be inserted into a keyboard, for example, or used as a single key switch.

The description and illustration of possible further details such as locking designs of switches or the like are omitted, since these are constructive developments that cannot contribute anything essential to the principle of the innovation.

Claims (4)

Patent Attorneys 1 1856.4 Ka/Kr Wenzel & Kalkoff PO Box 2448 Flaßkuhle 6 Witten/Ruhr Protection claims:10 1. Push button switch, in particular for keyboards, consisting of a housing in which a push button that can be operated by a band or with a finger for closing or opening of contacts, characterized in that a pin-in fuse (8) is arranged in the housing (1) below the push button (12), which is located in the current path which is «&ogr; sehalten ««iscJaen the inner contacts (4, 5) are closed or separated. 2. Push button switch according to claim 1, characterized in that the miniature fuse (8) is arranged in a switching bridge (6), by means of which the contacts (4, 5) are electrically connected or separated by pressing a button. 3. Push button switch according to claim 1 or 2, characterized in that the circuit breaker (8) is integrated in the housing (1) in a switching bridge (6) for two contacts (4, 5), which is connected on one side to one of the contacts (5) in an electrically conductive and preferably articulated and spring-loaded manner, and on the other side engages with or is separated from the other contact (4) at the push of a button. 4. Pushbutton switch according to claim 1 or 2, characterized in that the miniature fuse (8), the two connecting contacts (9, 10) of which both protrude on one side of the miniature fuse (8), is fastened to the pushbutton (12) below the base (15) thereof in such a way that the connecting contacts (9, 10) can be integrated _into a switching bridge (6) which can be placed onto or detached from the contacts (4, 5) with the pushbutton (12) for switching on and off. 5« Push button switch according to claim 4, characterized in that the miniature fuse (S) is attached with its contactless upper side to the base (15) of the push button (12). 6* Push button switch according to claim 4, characterized in that the miniature fuse (8) itself forms the switching bridge (16) and its connecting contacts (9, 10) for switching an electrical device on and off come into or out of engagement with the inner contacts (4, 5) in the housing (1)·