JPS61158640A - Operation switch circuit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an operation switch circuit that performs control according to the operation of a plurality of switches provided in the operation section of an electronic device. .

[Conventional technology]

An example of a conventional operation switch circuit of this type that includes a plurality of switches and performs control s1 according to the operation of the switches is shown in FIG. 4. This is done in response to the operation of each switch in the switch section 1.
The switch section 1 has n switches s, Ib, I..., Sn.
are provided, and one of these connection terminals is connected to the positive side of the direct power supply E through a common wiring s3.

In addition, the lamps Ll, L2+, -, of the main body 2 are connected in series with the other connection terminal of each switch S, S, ..., Sn.
L n are connected respectively, and these n lamps L
The negative side of the power supply E is connected to llffie...Ln.

When 1, for example, switch S1 is pressed on switch part 1, main body 2
The 0 lamp lights up, and when you press the switch Sat in the same way, the lamp L! lights up. In this way, each switch S,, S! .

..., each lamp L+e of the main body 2 in response to the operation of Sn.
L1. ..., Ln lights up, and the main body 2 can be controlled according to the operation of the switch section 1. In this case, n switches S, , S, ..., Sn and n lamps L,
, L, ..., Ln, switch section 1 is turned on.
n11 wires are required to connect the main body 2 and the main body 2.

[Problem that the invention seeks to solve]

In the operation switch circuit as described above, the wiring (electric wire) connecting the switch part 1 and the main body 2 is required according to the number of switches, so if there are many switches, the number of wiring will also increase. In addition to high costs, incorrect wiring is likely to occur.
Furthermore, if the distance between the switch section 1 and the main body 2 is long, there is a problem in that power loss in the wiring becomes large.

This invention takes into consideration the problems of the conventional ones.
The object of the present invention is to provide an inexpensive operation switch circuit that has a small number of wiring lines, can prevent incorrect wiring, and has low power loss.

[Means for solving problems]

The operation switch circuit of the present invention includes a plurality of switches connected in parallel, and a plurality of resistors that are respectively connected to these switches and change the resistance value at both ends of the parallel-connected circuit according to the operation of each switch. and C are provided.

[Effect]

When each switch is operated, the resistance value at both ends of the C parallel circuit changes in response to the operation, thereby making it possible to perform control according to the operation of each switch. In this case, only two wires are required to connect each switch and the control body, and power loss is also small.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

W! ! FIG. 1 is a block diagram of an operation switch circuit according to the present invention, and the same reference numerals as in the conventional circuit shown in FIG. 4 indicate corresponding parts. The switch section 1, which is the operation section of the main body 2, is connected to the main body 2 through two wires 3.4, and this switch section 1 has n switches 17) S1 m SR.
m ”” * S n and the resistor R connected in series with them
, , R, . . . , Rn are connected in parallel to each other to form a parallel circuit. The resistance values of the resistors R,, R,..., Rn connected in series with the switches S,, S,,..., Sn correspond to the operation of each switch. , that is, the line resistance values between wires 3 and 4 are set so as to vary. Also, in main body 2.

Detect the line resistance value of the above parallel circuit and change the A/D!
(analog-digital conversion) A/Df odor circuit 5;
A control circuit 6 is provided that performs various controls based on A/D converted signals.

In addition, each resistor R1e R1+... of the switch part 1.

Rn is switch s,,S,? ..., it does not matter which side of Sn it is connected to.

In the operation switch circuit configured as described above, each switch s, +S! +..., Sn is manipulated, the line resistance value between the two wires 3.4 changes in response to the manipulation. For example, when switch S is pressed, the line resistance value becomes the resistance value of resistor R1, and in the same way, C switch Sr+
Press to obtain the resistance value of resistor Rn. Also, switch S
i and S! The line resistance value when you press both at the same time is the resistance value of resistor R.
This is the resistance value when 5 and R1 are connected in parallel, and is smaller than the resistance value of the resistors R,,R,. In this way, each switch s,,S,,...

Since the line resistance value between the wires 3 and 4 changes in response to the operation of Sn, a signal corresponding to this line resistance value can be input to the A/D conversion circuit 5, and the control circuit 6 It becomes possible to perform control corresponding to the operation of each switch S, S2, . . . , Sn.

2J! FIG. 2 is a diagram showing an example of the A/D conversion circuit 5 and control circuit 6 of the main body 2. In this circuit, the input/D conversion circuit 5 is connected to a comparator 7.8.9 which is a voltage comparison tC.
．． 10 cb, three switches S, , S
, , Ss, the control circuit 6 is configured to control the lighting of the C lamps L, , L, , L3 in response to the operation of Ss.
．． 15 series circuits are connected, and the inverting input terminals 1-) of the comparators 7.8.9.10 are connected to their mutual connection points. The non-inverting input terminals (G) of comparators 7, 8.9.10 are connected to the negative side of power supply E via resistor 16, and the output terminals of comparators 7.8.9.10 are connected to resistor 17.1B, respectively. , 19.20 is connected to the base of the C transistor Q, ,Q, ,Q, ,Q,°
There is C. So C, lamp Ll sL! +Ls are connected between the power supply E and the transistor QI=QteQ1, respectively. Furthermore, diodes 01.0 . ．． 0. are connected, the paste of transistor Qt, the collector of transistor Qs and the paste of transistor Q
, and the respective diodes 0. ．． 0. A diode D6 is connected between the base of the transistor Q and the collector of the transistor Q.

In the circuit shown in Figure 12 above, the potential at point P is:

The potential is obtained by dividing the voltage VCC of the power source E by the line resistance value between the wirings 3 and 4 and the resistance value of the resistor 6. Here, the potential at point P when each switch S, , S, , S3 is pressed, that is, the potential for the input terminal of each comparator 7.8.9.10.

The potentials at points A, B, C, and D, that is, each comparator 7.
8, 9. The potential of the input terminal H of 10 is as shown in FIG. Switch S, O5! *If none of the S buttons are pressed, the potential at point P becomes the GND potential, and none of the comparators 7.8.9.10 outputs an output.1 For example, if switch Ss is pressed, the potential at point P becomes B. The potential becomes higher than the potential at the point, and an output is output from the comparator 7.8.9. At this time, the output of the comparator 9 causes the transistor Qs to become OFF.
When N, the output of comparator 7.8 is diode D,
, D as the collector current of the transistor Q, and the pace potential of the transistor Qs = Qt decreases.

Accordingly, the transistors Q, , Q, become OFI',
Only lamp L lights up. Do the same.

When switches S, ,S, are pressed, lamps L,
,L lights up. Also, switch SI.

When S, , S3 are pressed at the same time, the potential at point P becomes higher than the potential at point D, transistor Q4 turns on, and all lamps L, , L, , L turn on.

will no longer light up.

In this way, two wires s3 are connected between the switch section 1 and the main body 20.
．． Just connect with 4, each switch s, + s, l...
・Control corresponding to the operation of Sn (here, lamp lighting control) can be performed. At that time, each switch S,
S! ,..., resistor R1eRl connected in series with Sn
The resistance values of e..., Rn must be set so that the potentials at each point in FIG. 2 have the relationship shown in FIG. 3, for example.

Further, in the above embodiment, the input/D conversion circuit 5 is configured using a comparator, but it is also possible to use a microcomputer or an A/D converter.
It is clear that the same effect can be obtained using a conversion IC.

Note that this invention applies to electronic equipment (home appliances, office machines, measuring machines, etc.)
The present invention can be applied to an operating unit or a remote control device, and has beneficial effects.

〔Effect of the invention〕

As explained above, according to the present invention, a resistor is connected in series with each switch connected in parallel, and the resistance value at both ends of the circuit connected in the above column changes in response to the operation of each switch. Since there are many switches, only two wires between the operating section and the control body are required, and even if the two wires are connected in reverse, it will not affect the operation and will depend on the construction work. This has the effect of preventing troubles such as incorrect wiring. Additionally, since only a small amount of current flows through the two wires, thin wires can be used and power loss is small.

This has the effect of saving power and making it inexpensive. Furthermore, if an arbitrary number of switches are pressed at the same time, they can be made invalid, which has the effect of eliminating 14 operations.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of an embodiment of the present invention. FIG. 2 is a circuit diagram showing a specific example of the A/D conversion circuit and control circuit in FIG. 1, and FIG. 3 is a diagram showing the potential at each point in FIG. 2.
FIG. 4 is a circuit diagram showing a conventional example.

Claims (1)

[Claims] In an operation switch circuit that has multiple switches and performs various controls according to the operation of the switches, a resistor is connected in series with each switch, and these series circuits are connected in parallel to form a parallel circuit. An operation switch circuit characterized in that the resistance value of each resistor is set so that the resistance value at both ends of the parallel circuit changes in response to the operation of each switch.