Touch control arrangement for data entry

• US 4,495,485 A
• Filed: 08/31/1983
• Issued: 01/22/1985
• Est. Priority Date: 12/12/1980
• Status: Expired due to Fees

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Smith, Peter H.
• Primary Examiner(s): Crosland, Donnie L.
• Application Number:
  US06/528,075
• Time in Patent Office: 510 Days
• Field of Search: 340/365 C, 340/365 R, 340/365 E, 340/711, 200/DIG. 1, 200/52 R, 178/17 C, 179/90 K, 331/48, 331/65, 331/54, 331/55, 331/49, 219/10.55 E, 219/10.55 R
• US Class Current: 341/33
• CPC Class Codes: H03K 17/9622 using a plurality of detectors, e.g. keyboard
• CPC Class Codes: H03K 2017/9615 using three electrodes per touch switch
• CPC Class Codes: H03M 11/24 using analogue means , e.g. by coding the states of multiple switches into a single multi-level analogue signal or by indicating the type of a device using the voltage level at a specific tap of a resistive divider

Abstract

A touch control arrangement which employs a touch panel comprising a plurality of touch keys and a network of electrically connected capacitive elements; an oscillator which incorporates the network of capacitive elements in its timing circuit; and a microprocessor coupled to the output of the oscillator and operative to control various appliance operating components as determined by the frequency of the oscillator output signal. The keys of the touch panel are operatively coupled to the network of capacitive elements such that actuation of a key or pad by the user changes the equivalent capacitance of the timing circuit causing the oscillator a generate a control signal at the frequency associated with the actuated key.

Claims

1. A touch control arrangement for an appliance of the type incorporating a plurality of appliance operating components arranged for selective actuation in accordance with use generated input data, said touch control arrangement comprising:

touch responsive data entry means arranged for user actuation comprising a plurality of touch keys and a capacitive network including a plurality of capacitive elements operatively coupled to said touch keys;

oscillating means for generating a control signal at a plurality of discrete predetermined frequencies;

each of said touch keys being uniquely associated with a different one of said plurality of predetermined frequencies, said capacitive network being coupled in tuning relationship with said oscillating means such that the frequency of said control signal is determined by the selective touching of said touch keys by the user; and

a microprocessor responsive to said control signal operative to control appliance operation in a manner determined by the frequency of said control signal.

2. A touch control arrangement in accordance with claim 1 wherein said touch keys are constructed and arranged to selectively change the effective capacitance of said capacitive network, thereby tuning said oscillating means to that one of predetermined frequencies associated with the user-actuated key.

3. A touch control arrangement for an appliance comprising:

a plurality of touch keys arranged for user actuation;

oscillating means for generating a control signal tunable to a plurality of discrete predetermined frequencies, different ones of said predetermined frequencies being uniquely associated with different ones of said touch keys;

tuning means comprising a capacitive network including a plurality of capacitive elements, said network being coupled into tuning relationship with said oscillating means, said touch keys being coupled to said capacitive network to change the effective capacitance of said capacitive network such that user-actuation of one of said touch keys tunes said oscillating means to that one of said plurality of frequencies uniquely associated with said one touch key; and

a microprocessor responsive to said control signal and arranged to control appliance operation in accordance with the frequency of said control signal.

4. A touch control arrangement in accordance wtih claim 3 wherein said plurality of capacitive elements are serially interconnected and said touch keys are arranged to change the effective capacitance of said capacitive network by selectively shunting portions of said capacitive network.

5. A touch control arrangement in accordance with claim 3 wherein said touch keys and capactive elements are contstructed and arranged to permit the body capacitance of the user, when touching one of said touch keys, to change the effective capacitance of one element of said capacitive network.

6. A touch control arrangement in accordance with claim 3 wherein said capacitive elements form a plurality of strings of capacitive elements, each string comprising a plurality of capacitive elements connected in electrical series, said strings being connected in electrical parallel, and said touch keys being operative to change said effective capacitance of said capacitive network by selectively shunting portions of said capacitive network.

7. A touch control arrangement in accordance with claim 3 wherein said capacitive network comprises a plurality of strings of capacitive elements, each string comprising a plurality of capacitive elements connected in electrical series, said strings being connected in electrical parallel, and said touch keys being constructed and arranged to permit the body capacitance of the user when touching one of said touch keys, to change the effective capacitance of said capacitive network.