JPS5916227A - Keyboard device - Google Patents

Abstract

1. Keyboard the keys (22) of which are mounted on a printed circuit board (23), characterized in that below the printed circuit board (23) there is provided a foamed plastic molded body (27) which supports the printed circuit board (23) without any further supporting elements and over almost its entire surface against flexure due to key operations.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a key gate apparatus in which the key is mounted on a printed circuit board.

For this type of keyboard device, either the printed circuit board supporting the keys must be supported, or the key actuation force must be taken by another element. For this reason, conventional keyboard devices of this type are provided with a blind plate, for example, in front or behind the printed circuit board. The blind plate in front of the printed circuit board is usually a metal plate with a corresponding cutout for each key, into which the key is inserted, a key element as described in Swiss Patent No. 596,460. The key element is secured by a resilient notch, such as notch 254, while its electrical terminals are brazed to a printed circuit board located behind the key element. It is clear that this blind plate is relatively expensive due to the large number of cutouts required. The metal blind plate behind the printed circuit board shall be insulated against the printed circuit board;
On the other hand, the blind plate made of insulating material must be of sufficient thickness or have a lip, resulting in a heavy and bulky blind plate.

It is therefore an object of the present invention to provide a key gate device with good support means for printed circuit boards without the drawbacks of conventional support means.

The key gate device based on this invention has a foamed plastic molded body below the printed circuit board, and the molded body supports the printed circuit board on almost the entire surface against bending due to key replacement. It is characterized by what it did.

Examples will be described below with reference to the accompanying drawings.

FIG. 1 shows a top view of a keygate device including two keyboards, and FIG. 2 shows a cross-sectional view of this device. The keyboard device shown in FIG. 1 includes a cover 11 having openings for a character keypad 12 and a keypad 13 containing, for example, function keys. As is clear from the cross-sectional view shown in FIG. 2, the cover 21 has a small angle of inclination with respect to a support surface (not shown) and gradually increases in height from the front end on the left side of the figure toward the rear, and after a small offset, the cover 21 It rises above and bends twice behind the key gate and bends toward the support surface (downward). A key element 22 is mounted on a printed circuit board 23 arranged under the cover 21. Another printed circuit board 25 on which an evaluation circuit 26 is mounted is connected via a connector 24 to the upper end of the printed circuit board 23 (the right end in FIG. 2). Connector 24 is preferably brazed to printed circuit board 25 to receive printed conductors for plugging on printed circuit board 23.

The printed circuit board 23 on which the key element 22 is mounted is connected to the cover 21
It fills the space left below and is supported by a foamed plastic, Kumold body 27 fixed thereto.

The use of this expanded plastic, co-molded body allows for a substantial savings in parts and thus weight. In addition to the ease of key movement desired for keyboards that are used only for occasional data output and then put away, the reduced weight results in a lighter structure and reduces collision energy. It can withstand drop tests by reducing the

The principle of supporting the keypad by a foamed plastic mold can be applied with good results to the keyboard device shown in FIG. It is European mother patent EPOO5522
No. 0 (Application No. 81810506.6 1 Inventor Fre
The keyboards 31, 32, 33 are inclined relative to each other to provide support for the hands and arms of the operator in accordance with the usual work engineering. They have different angles of inclination relative to the supporting surface so that In the case of the key gate device described above, it is advantageous to provide a single foamed plastic, Kumold body with a cavity for each key gate into which an individual keyboard with a rim can be inserted.

two printed circuit boards 23 connected by connectors 24
．． In the case of a keyboard with a transformer by dividing the electrical circuit into 25 parts, for a relatively large printed circuit board containing the primary and secondary windings of the key transformer and supporting the key element, there is no This has the advantage of allowing the use of inexpensive double-sided printed circuits that do not require any through-hole plating or brazing. Since this printed circuit board does not have a brazing section, it is also permissible to place it directly on a foamed plastic mold, and it is also possible to insert an insulating foil in between. Although the evaluation circuit requires a through-plating layer, it can be placed on a relatively small printed circuit board 25. Although an additional connector is required to connect the two printed circuits, these three components together are much less expensive than a single large printed circuit board with a through-plating layer.

Furthermore, since the evaluation circuit does not require any additional space in the depth or width of the keyboard device, and is located in the space provided by the slope of the keyboard required for operational engineering, this division allows for the desired keystrokes to be accommodated as much as possible. Allows for a small keyboard structure. The split also simplifies the design of the foam plastic mold and makes it easier to replace the evaluation circuit in case of failure.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a keypad device with two keyboards, FIG. 2 is a sectional view of the device of FIG. 1, and FIG. 3 has three keypads tilted to each other. FIG. 3 is a plan view of the keyboard device. 1 no...Cover, 12.13.31.32゜33...
・Keepad, 21...Cover, 22...Key element, 23.25...Printed circuit board, 24...Connector,
26... Evaluation circuit element, 27... Foamed glass mold body. 0 Kenshu, 268 Mr. Kazuo Wakasugi, Commissioner of the Japan Patent Office, Patent Application No. 1987-65735 2, Name of Invention Key is Key to - Code Device 3 Supplement [13] Relationship with the Nagisa Case Patent Applicant international standard electric
Co-op Region 4, Agent July 26, 1981 128-

Claims (5)

[Claims] (1) In a single key device in which the key is attached to a printed circuit board, a foamed plastic molded body is provided under the printed circuit board, and this foamed plastic molded body only resists bending due to key operation. A key date device characterized in that it supports a printed circuit board on almost its entire surface. (2) Claim d characterized in that one or more printed circuit boards supporting the key elements are inserted into a cavity of a foamed plastic molding that completely encloses the keyboard device together with a corresponding cover or rim. Key date device 0 described in range 1 (3) A non-contact key element (22) in which a Granger-type magnetic core is inserted into the corresponding key transformer of the printed circuit board
an evaluation circuit (26) mounted on at least one first printed circuit board (23) arranged below each (21);
connects the connector (24) to the first printed circuit board (23).
A first printed circuit board (2) on which a key element (22) is mounted, which is arranged on a second printed (b) nameplate (25) connected to
3) has a foamed plastic mold body (27
) characterized in that it is supported by %l'f
The key date device according to the first or second item of the Ru search range. (4) The second printed circuit board (25) is connected to the first printed circuit board (
23), the connector (24) is brazed to the second printed circuit board (25), the first printed circuit board being provided with printed conductors that can be directly plugged. A keyboard device according to claim 3. (5) The key elements are arranged on two or more first printed circuit boards, and the printed circuit boards are designed to reduce bending and stretching of the operator's wrist joints compared to a key date device integrated into the vehicle. 4. A keyboard device according to claim 3, wherein the keyboard devices are inclined relative to each other and to the support surface of the key gate device.