JPH0315431U - - Google Patents

Description

【図面の簡単な説明】[Brief explanation of drawings]

第１図ａは本考案の一実施態様の下基板の平面
図、ｂは同基板の電気的等価回路図、第２図ａは
本考案の他の実施態様の下基板の平面図、ｂは同
基板の電気的等価回路図、第３図ａは従来のキー
入力装置の下基板平面図、上基板底面図、ｂはキ
ー入力盤の平面図、ｃはｂの−線に沿う縦断
面図、ｄはキー入力装置の電気的等価回路図、第
４図は従来のキー入力装置において二つの接点を
同時に押し場合の短絡電流を示す説明図、第５図
は従来のキー入力装置の他の例の電気的等価回路
図である。 １……下基板、２……キー検出抵抗膜、３，４
……電極、５，６……定電圧入力端子、７……検
出点、８……接点、９……キー検出端子、１０…
…絶縁スペーサ、１１……上基板、１２……折り
曲げ線、１３……キー押圧子、１４……デイスプ
レーシート、１５……キー円板、１６……支持基
板、１７……定電圧電源、１８……バツフアアン
プ、１９……短絡電流、２０……電流制限抵抗膜
。 FIG. 1a is a plan view of the lower substrate of one embodiment of the present invention, b is an electrical equivalent circuit diagram of the same substrate, FIG. 2a is a plan view of the lower substrate of another embodiment of the present invention, and b is An electrical equivalent circuit diagram of the same board, Fig. 3a is a plan view of the lower board of the conventional key input device, a bottom view of the upper board, b is a plan view of the key input panel, and c is a vertical cross-sectional view along the - line of b. , d is an electrical equivalent circuit diagram of the key input device, FIG. 4 is an explanatory diagram showing the short circuit current when two contacts are pressed simultaneously in a conventional key input device, and FIG. 5 is an illustration of another conventional key input device. FIG. 3 is an electrical equivalent circuit diagram of an example. 1...Lower substrate, 2...Key detection resistive film, 3, 4
... Electrode, 5, 6 ... Constant voltage input terminal, 7 ... Detection point, 8 ... Contact, 9 ... Key detection terminal, 10 ...
... Insulating spacer, 11 ... Upper substrate, 12 ... Bending line, 13 ... Key presser, 14 ... Display sheet, 15 ... Key disc, 16 ... Supporting board, 17 ... Constant voltage power supply, 18... Buffer amplifier, 19... Short circuit current, 20... Current limiting resistive film.

Claims (1)

【実用新案登録請求の範囲】 １ 絶縁性基板の一面に配設した帯状キー検出抵
抗膜に定電圧を加え、該キー検出抵抗膜上に設け
た各検出点の電位を、該各検出点に接続された接
点のうち押圧されて導通状態となつた接点を介し
て検出し、この電位より押圧接点を検知するキー
入力装置において、接点とバツフアアンプとの間
に電流制限用抵抗膜を設けてなることを特徴とす
るキー入力装置。 ２ 前記電流制限用抵抗膜は各接点とバツフアア
ンプとの間に設けられている請求項１に記載の装
置。 ３ 前記電流制限用抵抗膜は複数個の組に分けた
接点の各組とバツフアアンプとの間に設けられて
いる請求項１に記載の装置。[Claims for Utility Model Registration] 1. Applying a constant voltage to a strip-shaped key detection resistor film disposed on one surface of an insulating substrate, and applying the potential of each detection point provided on the key detection resistor film to each detection point. A key input device that detects a pressed contact through a contact that is pressed and becomes conductive among the connected contacts, and detects the pressed contact from this potential, in which a current-limiting resistive film is provided between the contact and the buffer amplifier. A key input device characterized by: 2. The device according to claim 1, wherein the current limiting resistive film is provided between each contact and a buffer amplifier. 3. The device according to claim 1, wherein the current limiting resistive film is provided between each of the plurality of groups of contacts and the buffer amplifier.