JP2003212066A - Switch device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a switch device capable of being driven even when ignition is off, and preventing a battery from going flat. <P>SOLUTION: This device comprises a diode matrix circuit 2 equipped with a diode, or a series connection circuit of the diode and a switch at a point where a plurality of input lines are crossed with a plurality of output lines; a first voltage supply circuit 4 installed on the input side of the diode matrix circuit 2 having resistors R1-R3, and supplying a voltage of 5 volts to each input line via the resistors R1-R3 when the ignition is on; a second voltage supply circuit installed on the input side of the diode matrix circuit 2 having resistors R11-R14 (whose resistance values are extremely smaller than those of the resistors R1-R3), and supplying a voltage of 5 volts to each input line; and a switching circuit connected with the output line of the diode matrix circuit 2, and driving each output line sequentially. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switch device for turning on and off each device mounted on a vehicle.

[0002]

2. Description of the Related Art A combination switch mounted on a vehicle has various kinds of operation functions such as operation of a wiper, operation of a headlight, and the like. If an electric wire for connecting a switch is provided for each of these functions, Since the number of electric wires is large and complicated, a structure in which the number of electric wires is reduced by using a diode matrix circuit has been conventionally used.

FIG. 2 is a circuit diagram showing a configuration of a switch device using a diode matrix circuit which has been conventionally used. As shown in FIG.
1 includes a diode matrix circuit 102, a switching circuit 103, and a voltage supply circuit 105 that outputs a power supply voltage when the vehicle ignition is turned on.

Further, the diode matrix circuit 102
Is a plurality of diodes D1 to D9 and a switch SW1.
To SW6. And each switch SW1-S
Various operations such as a headlight and a wiper mounted on the vehicle are assigned to W6.

The voltage supply circuit 105 includes three resistors R1 to R1.
The switching circuit 103 has R3, and has three transistors TR1 to TR3. Also, reference numeral 106
Is a harness that connects the diode matrix circuit 102 and the switching circuit 103.

In such a switching device 101, each transistor T included in the switching circuit 103 is
To the gates of R1 to TR3, for example, at a cycle of 10 msec,
The drive signal is output in sequence. Therefore, each switch S
Depending on the on / off state of W1 to SW6, the output points P1 to P1
Since the voltage level of P3 changes, the on / off state of the switches SW1 to SW6 can be detected by detecting this voltage level.

For example, when the switch SW1 is turned on and the other switches SW2 to SW6 are turned off, outputs (P1, P2, P3) are output when the transistor TR1 is energized.
Becomes (H, L, L). However, "H" is 5 volts,
"L" indicates 0 volts.

By adopting such a configuration, it is possible to reduce the number of electric wires with respect to the number of switches.

[0009]

However, in the above-mentioned conventional switch device 101, the switching circuit 1 is used.
Since the transistors TR1 to TR3 included in 03 are sequentially energized and a voltage of 5 V is output from the output points P1 to P3, power is consumed. Therefore,
There is no problem when the ignition of the vehicle is turned on, but if the operation is continued for a long time when the ignition is turned off, the battery may be exhausted. Therefore, when the ignition is off, the switch device 101 is not operated, and when the ignition is off, various switch operations cannot be performed.

The present invention has been made to solve such a conventional problem, and an object thereof is to perform an on / off operation of each device even when the ignition is off. The object is to provide a switch device that can do so.

[0011]

In order to achieve the above-mentioned object, the invention according to claim 1 of the present application is a switch device for controlling a plurality of switches for turning on / off a vehicle-mounted device. And a diode matrix circuit having a plurality of output lines, the diode matrix circuit comprising a diode or a series connection circuit of the diode and the switch at a plurality of points of intersection of the input line and the output line, A first resistance circuit which is installed on the input side and which supplies a direct current voltage to each of the input lines through the first resistance circuit when the ignition is turned on;
Voltage supply circuit and a second resistance circuit, which is installed on the input side of the diode matrix circuit and has a resistance value larger than that of the first resistance circuit, and each input is performed via the second resistance circuit. It is characterized by comprising a second voltage supply circuit for supplying a DC voltage to the line, and switching means connected to the output line of the diode matrix circuit and driving each output line in order.

According to a second aspect of the present invention, the first voltage supply circuit includes a sneak prevention circuit that prevents a DC voltage from sneaking from the second voltage supply circuit when the ignition is turned off. And

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a circuit diagram showing a configuration of a switch device according to an embodiment of the present invention. As shown in the figure, the switch device 1 is used as a combination switch mounted on a vehicle, and includes a diode matrix circuit 2, a switching circuit (switching means) 3, and a power supply voltage when the vehicle ignition is turned on. A first voltage supply circuit 4 for outputting and a second voltage supply circuit 5 for outputting a power supply voltage when the ignition is off,
It is equipped with.

Further, the diode matrix circuit 2 includes a plurality of diodes D1 to D9 and switches SW1 to SW.
Have six. The switches SW1 to SW6 are assigned various operations such as headlights and wipers mounted on the vehicle. Further, the input line of the diode matrix circuit 2 is connected to the electric wires W1 to W3, and the output line thereof is connected to the harnesses 31 to 33.

The second voltage supply circuit 5 has three resistors R1.
To R3 (second resistance circuit), the first voltage supply circuit 4 has four resistors R11 to R14 (first resistance circuit).
And diodes D11 to D13 for preventing voltage sneak
The circuit includes a (wraparound prevention circuit) and a transistor TR11.

The first voltage supply circuit 4, the second voltage supply circuit 5, and the diode matrix circuit 2 are
They are connected via three electric wires W1 to W3. That is, the electric wire W1 is connected to the voltage of 5 volts via the resistor R1, and is also connected to the collector of the transistor TR11 via the diode D11 and the resistor R11.

Similarly, the electric wire W2 is connected to the voltage 5V via the resistor R2, and is connected to the collector of the transistor TR11 via the diode D12 and the resistor R12, and the electric wire W3 is connected to the voltage 5V via the resistor R3. , And the transistor TR via the diode D13 and the resistor R13.
It is connected to 11 collectors.

The resistance values of the resistors R11 to R13 are set to sufficiently smaller values than the resistance values of the resistors R1 to R3.

The collector of the transistor TR11 is grounded through the resistor R14, and the emitter is connected to a voltage of 5 volts. Further, the transistor TR11
A drive signal is given to the base of the vehicle when the ignition of the vehicle is turned on.

The switching circuit 3 comprises three transistors TR1 to TR3, and each transistor TR1
The emitters of 1 to TR3 are grounded. Further, the switching circuit 3 and the diode matrix circuit 2 are
The harness 31 is connected to the collector of the transistor TR1, the harness 32 is connected to the collector of the transistor TR2, and the harness 33 is connected to the collector of the transistor TR3.

The gates of the transistors TR1 to TR3 included in the switching circuit 3 are, for example, 10 m.
The drive signal is applied in sequence at a cycle of sec.

Next, the operation of this embodiment configured as described above will be described. Now, when the ignition mounted on the vehicle is turned on, a drive signal is applied to the gate of the transistor TR11.
11 is turned on, and a voltage of 5 V is applied to each of the electric wires W1 to W3 via the resistors R11 to R13 (hereinafter, this is referred to as a “normal mode” in comparison with a low power consumption mode described later). . Further, as described above, the driving voltage is sequentially applied to the gates of the transistors TR1 to TR3 at a cycle of 10 msec, so that the transistors TR1 to TR3
On to TR3 are sequentially switched on and off in this cycle.

In this state, for example, when the switch SW1 of the diode matrix circuit 2 is turned on, when the transistor TR1 is turned on, the voltages of the electric wires W2 and W3 fall to the ground. That is, the voltage of 5 V of the first voltage supply circuit 4 is applied to the resistor R13, and the electric wire W3 becomes approximately 0 V (hereinafter, referred to as L level). Similarly, since the switch SW1 is turned on, the electric wire W3 also becomes L level. On the other hand, since the switch SW2 is turned off, the electric wire W1
Is approximately 5 volts (hereinafter, this is referred to as H level).
Therefore, the output signals (P1, P2, P3) are (H, L,
L).

Next, when the on-time (10 msec) of the transistor TR1 of the switching circuit 3 elapses and the transistor TR2 is turned on, both the switches SW3 and SW4 are off, so the output signals (P1, P2, P3).
Becomes (H, L, H). When the transistor TR3 is turned on, both the switches SW5 and SW6 are turned off, so that the output signals (P1, P2, P3) are (L, H,
H).

Then, based on these results, it can be detected that the switch SW1 is on.

When the ignition of the vehicle is turned off, the drive signal applied to the gate of the transistor TR11 of the first voltage supply circuit 4 is turned off.
The power supply voltage of 5 volts is not supplied to the voltage supply circuit 4 of FIG. Instead, the voltage (5 volts) output from the second voltage supply circuit 5 is applied to each of the electric wires W1 to W3. That is, the same operation as described above is performed by the voltage output from the second voltage supply circuit 5 (
"Low power consumption mode"). Therefore, even if the ignition is turned off, the switches SW1 to SW6
It is possible to detect the on and off states of.

Here, as described above, the resistors R1 to R3.
Has an extremely large resistance value with respect to the resistors R11 to R13, so that the power consumption is remarkably reduced compared to when the ignition is on. Therefore, even when the switch device 1 is operated when the ignition is off, the battery exhaustion problem hardly occurs.
The switch device 1 can be operated even when the ignition is off.

The reason why the low power consumption mode and the normal mode are switched will be described below. In the low power consumption mode, since the resistance values of the resistors R1 to T3 are large, the current value is small, and if the wires are used for a long time, the connection points between the wires W1 to W3 or the harnesses 31 to 33 and the diode matrix circuit 2 are reduced. An oxide film may be formed and become non-conductive. On the other hand, when the normal mode is set, the current value increases and the oxide film can be removed, so that the non-conduction state can be avoided. Therefore, when the ignition is on, the normal mode is set, and when it is off, the low power consumption mode is set.

As described above, in the switch device according to the present embodiment, the operation of the switches SW1 to SW6 is reliably detected by setting the normal mode when the ignition is on and the low power consumption mode when the ignition is off. It is also possible to prevent the battery from running down when the ignition is turned off.

By providing the first voltage supply circuit 4 with diodes D11 to D13 for sneak prevention, the voltage output from the second voltage supply circuit 5 spills to the first voltage supply circuit 4 side. It is possible to prevent malfunction.

The switch of the present invention has been described above based on the illustrated embodiment, but the present invention is not limited to this, and the configuration of each part is replaced with an arbitrary configuration having the same function. be able to.

For example, in the above-described embodiment, an example in which the 3 × 3 diode matrix circuit 2 is used has been described, but the present invention is not limited to this and 2 × is used.
It is also possible to apply to a diode matrix circuit of 2 or 4 × 4 or more.

[0033]

As described above, according to the present invention, when the ignition of the vehicle is on, the voltage output from the first voltage supply circuit is used to turn on / off each switch of the diode matrix circuit. Detect the condition,
When the ignition is off, the voltage output from the second voltage supply circuit is used to detect the on / off state of each switch. Therefore, even when the ignition is off, the diode matrix circuit can be driven and the battery exhaustion can be prevented.

Also, by providing the sneak prevention circuit, the voltage output from the second voltage supply circuit does not sneak into the first voltage supply circuit side, and malfunction can be prevented.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a configuration of a switch device according to an embodiment of the present invention.

FIG. 2 is a circuit diagram showing a configuration of a conventional switch device.

[Explanation of symbols]

1 switch device 2 diode matrix circuit 3 Switching circuit (switching means) 4 First voltage supply circuit 5 Second voltage supply circuit W1-W3 electric wire SW1 to SW6 switches D1-D9 diode 31-33 harness

Claims (2)

[Claims] 1. A switch device for controlling a plurality of switches for turning on and off a vehicle-mounted device, the switch device having a plurality of input lines and a plurality of output lines, wherein the input lines intersect the output lines. , A diode matrix circuit having a diode or a series connection circuit of a diode and the switch, and a first resistance circuit installed on the input side of the diode matrix circuit, and each of the inputs when the ignition is turned on. A first voltage supply circuit that supplies a DC voltage to the line through the first resistance circuit; and a second voltage supply circuit that is installed on the input side of the diode matrix circuit and has a resistance value larger than that of the first resistance circuit. A second voltage supply circuit having a resistance circuit for supplying a DC voltage to each of the input lines via the second resistance circuit; and an output of the diode matrix circuit. Is connected to line, the switch device being characterized in that comprising a switching means for driving the respective output line in turn, a. 2. The first voltage supply circuit includes a sneak prevention circuit that prevents a DC voltage from sneaking from the second voltage supply circuit when the ignition is turned off. Switch device.