JPH06107024A - Switch circuit - Google Patents

Abstract

PURPOSE:To provide a switch circuit for reducing the number of wire harnesses wired inside of a car body. CONSTITUTION:A shift switch 2 (operation unit) provided with switches SW1-SW6 of which one end of each is connected to between respective resistors R1-R7 of a voltage dividing resistance circuit whose resistors R1-R7 are connected in series to each other and a positive power supply voltage is supplied to one end thereof and whose the other end is grounded, and of which the other end of each is connected to each other in common, and for generating a level signal in accordance with switch operation, is constituted. A judging circuit for comparing the level signal with preset reference potential to drive a load in accordance with a comparison result thereof is equipped, and this judging circuit is connected to the shift switch 2 with at least one signal line for feeding the level signal.

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a switch circuit capable of reducing the number of wire harnesses wired inside a vehicle body.

[0002]

2. Description of the Related Art As is well known, in general vehicles,
Various display lamps are provided on the instrument panel, and, for example, the state of the side brake, the open / closed state of the door, etc. are displayed according to the lighting state of these. Further, in recent years, many vehicle types have an AT (automatic transmission) shift lever setting state displayed on the panel. In this case, the pilot lamp arranged on the instrument panel is turned on in response to the shift operation to display the set position of the shift lever.

FIG. 5 is a circuit diagram showing a structural example of a switch circuit for displaying such a shift operation state. In the figure, reference numeral 1 is a shift operation display section arranged on the instrument panel, and pilot lamps PL1 to PL6 are provided.
Equipped with. Here, the lamps PL1 to PL6 respectively display the set position of the AT shift lever,
For example, when the lamp PL1 is turned on, "parking (P)" is indicated, and when the lamp PL2 is turned on, "reverse (R)" is indicated. Further, lamps PL3 to PL6 represent shift setting positions of "neutral (N)", "drive (D)", "second speed (2)", and "first speed (1)", respectively.

One end of each of the pilot lamps PL1 to PL6 is connected to the positive power supply voltage + V _B via the fuse FS, and the other ends are connected to the shift switch 2, respectively. The shift switch 2 is set to an ON state in conjunction with the operation of an AT shift lever provided at the center of the floor of the vehicle body, and is composed of switches SW1 to SW6 corresponding to the lamps PL1 to PL6. One ends of these switches SW1 to SW6 are connected in series with pilot lamps PL1 to PL6, respectively, and the other ends are commonly grounded to the chassis.

Therefore, any one of these switches SW1 to SW6 is turned on in accordance with the operation of the AT shift lever, and the lamp PL corresponding thereto is turned on. For example, when the AT shift lever is set to the position for turning on the switch SW1, the pilot lamp P
L1 is lit to indicate that it is "parking (P)". Two or more of these switches SW1 to SW6 are not set to the ON state at the same time, and one of them is always in the ON state.

Such a switch circuit is wired to the vehicle body 3 in the form shown in FIG. First, the pilot lamp PL
The power supply lines connected to 1 to PL6 are connected to the shift operation display unit 1 from the joint box JB. Further, from the lamps PL1 to PL6 to the shift switch 2, wiring is once performed from the shift operation display unit 1 to the connector CN arranged in the cowl side portion, and from this connector CN to the shift switch 2 via the lower portion of the driver's seat 3a. I'm trying to get around.

Next, FIG. 7 is a circuit diagram showing a modification of the switch circuit shown in FIG. That is, the switch circuit shown in FIG. 5 has the pilot lamp PL1 on the positive power supply voltage side.
~ PL6 are connected and the shift switch 2 is connected to the ground side, whereas in the modification shown in this figure, the shift switch 2 is connected to the positive power supply voltage side and the pilot lamps PL1 to PL6 are connected to the ground side. It is configured to be connected.

The switch circuit according to this modification is wired on the vehicle body 3 in the form shown in FIG. In this case, the ground lines connected to the pilot lamps PL1 to PL6 are connected to the shift operation display unit 1 via the ground connector ECN connected to the chassis. Also, the lamps PL1 to PL
From 6 to the shift switch 2, the display portion 1 is once wired to the connector CN arranged at the cowl side portion, and is routed from the connector CN to the shift switch 2 via the lower portion of the driver's seat 3a. Further, the power supply line is routed from the joint box JB to the shift switch 2 via the lower portion of the driver's seat door 3a.

[0009]

By the way, in the above-mentioned conventional switch circuit, pilot lamps PL1 to PL are used.
6 and the corresponding switches SW1 to SW6 are individually connected in series, so that the number of wire harnesses required for wiring increases. For example, when wiring a certain vehicle type in the form shown in FIG. 6, the total wiring length of the wire harness reaches 14.8 m,
The number of contacts (connection points) also reaches 22 points. Further, according to the wiring form shown in FIG. 8, the total wiring length is 16.2 m and the number of contacts is 23.

As described above, even with a circuit configuration in which a lamp and a switch are simply connected in series, the weight of the wire harness cannot be ignored due to the large number of wires, and as a result, the weight of the vehicle body is reduced. Will lead to an increase. Moreover,
The large number of wires complicates harness wiring work and connector connection work, thus deteriorating workability. After all, these various adverse effects lead to an increase in cost and a decrease in productivity, and in some cases, an increase in the number of contacts may cause a decrease in reliability.
Therefore, it is desirable that the number of wire harnesses wired inside the vehicle body be reduced as much as possible. In particular, with the recent trend toward electronic control, the number of wire harnesses for wiring the inside of a vehicle tends to increase, and for this reason, there is a current demand for harness reduction. The present invention has been made in view of the above-mentioned circumstances, and an object thereof is to provide a switch circuit capable of reducing the number of wire harnesses wired inside a vehicle body.

[0011]

According to the present invention, a plurality of resistors are connected in series, a positive power supply voltage is supplied to one end thereof, and the other end is grounded, and a voltage dividing resistor circuit is provided between the plurality of resistors. A plurality of switches, one end of which is connected and the other end of which is commonly connected, and a manipulator that generates a level signal according to the switch operation, and compares the level signal with a preset reference potential, A determination circuit for driving a load according to the comparison result is provided, and the determination circuit and the operating element are connected by at least one signal line that supplies the level signal.

[0012]

According to the above construction, the operator generates a level signal according to the switch operation, the judging circuit compares the level signal with a preset reference potential, and drives the load according to the comparison result. . Therefore, since the manipulator and the determination circuit are connected by at least one signal line that supplies the level signal, the number of wire harnesses wired between them is reduced.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. A. Configuration of the Embodiment FIG. 1 is a circuit diagram showing the overall configuration of an embodiment according to the present invention. The parts common to those shown in FIG. 5 are designated by the same reference numerals and the description thereof will be omitted. In this figure, 1a
-1 to 1a-6 are comparators, which compare the reference voltage V _ref supplied to the inverting input terminal with the input voltage V _in supplied to the non-inverting input terminal, and when V _in > V _r The output signal of the "level" is generated, and the output signal of the "L" level is generated otherwise.

R _{1 to} r ₇ are voltage _dividing resistors for generating reference voltages V _{ref1 to} V _ref6 . The voltage dividing resistors r _{1 to} r _{7 form} a series circuit, and the voltage + V _C is applied to one end of the series circuit and the other end is grounded. Here, dividing resistors r ₁ ~r ₆ supplies a reference voltage V _ref1 ~V _Ref6 to each inverting input terminal of the comparator 1a-1~1a~6.

On the other hand, level signals (input voltage) supplied to the non-inverting input terminals of the comparators 1a-1 to 1a-6.
V _{in1 to} V _in6 are switches SW1 on the shift switch 2 side
~ Given by turning on SW6. The level signals (input voltage) V _{in1 to} V _in6 are generated by the voltage _dividing resistors R _{1 to} R ₇ . The voltage dividing resistors R _{1 to} R ₇ are connected in series, and the voltage + V is applied to one end of the series circuit.
_C is applied and the other end is grounded.

The input voltage generated by the voltage dividing resistors R _{1 to} R ₆ is supplied to one end of each of the switches SW1 to SW6. The other ends of the switches SW1 to SW6 are commonly connected and input to the non-inverting input terminals of the comparators 1a-1 to 1a to 6, respectively. That is, the switch SW
When any one of 1 to SW6 is set to the ON state, the level signal (input voltage) V _{in1 to} V in accordance with this is input.
_in6 is supplied to the comparators 1a-1 to 1a-6. The reference voltage and the input voltage input to the comparators 1a-1 to 1a-6 are V _in1 > V _ref1 , V ref
_in2 > V _ref2 , ..., V _in6 > V _ref6 , and V _in1 > V _in6
And V _ref1 > V _ref6 such that the voltage _dividing resistor r ₁
~ R ₇ and R _{1 to} R ₇ are defined.

Next, 1b-1 to 1b-5 are AND gates, and one of the two input terminals is formed as an inverting input terminal. The outputs of the comparators 1a-1 to 1a-5 are connected to the inverting input terminals of the AND gates 1b-1 to 1b-5, and the comparators 1a-2 to 1a-6 are connected to the other input terminal.
The output of each is supplied. Tr1 to Tr6 are switching transistors (FETs) connected in series to the pilot lamps PL1 to PL6. Of these switching transistors Tr1 to Tr6, the transistor Tr
The output of the comparator 1a-1 is input to the gate terminal of 1 and the outputs of the AND gates 1b-1 to 1b-5 are input to the gate terminals of the transistors Tr2 to Tr6, respectively.

B. Operation of the Embodiment In the above-described configuration, for example, when the switch SW1 is set to the ON state in response to the AT shift lever operation, the comparator 1a-1 generates an “H” level output signal, which causes the transistor Tr1 to be in the ON state. Then, the pilot lamp PL1 is turned on. In this case, the other comparators 1a-2 to 1a-6 similarly generate output signals of "H" level, but these are AND gates 1b-1 to 1b-1.
Since it is supplied to the inverting input terminal of b-5, these comparators 1a-2 to 1a-6 maintain the output of "L" level. Therefore, the other transistors Tr2 to Tr6 are not turned on.

Next, if the switch SW2 is set to the ON state, an "L" level signal is supplied to the inverting input terminal of the AND gate 1b-1 and "H" is supplied to the other input terminal.
Since the level signal is supplied, this AND gate 1b
-1 produces an "H" level output. As a result, the transistor Tr2 is turned on and the pilot lamp PL2 is turned on. At this time, as in the above-described operation, the comparators 1a-3 to 1a-6 maintain the "L" level output, so that the other pilot lamps PL3 to PL6 are not lit. Then, when the switches SW3 to SW6 are sequentially turned on, the AND gates 1b-2 to 1b-2 to
1b-5 generates an output signal of "H" level, and the pilot lamps PL3 to PL6 are turned on in order to perform a display operation.

As described above, according to the above-described embodiment, the level signal is generated by changing the ratio of the combined resistance in response to the shift lever operation on the shift switch 2 side, and the level signal is generated on the shift operation display section 1 side. Since the corresponding pilot lamp is turned on based on the above, the shift switch 2 and the shift operation display unit 1 are connected only by the wire harnesses L1 and L2 that supply the level signal.
As a result, it is not necessary to separately connect the lamp and the switch as in the conventional case, so that the number of wire harnesses required for wiring can be reduced.

When wiring such a switch circuit to the vehicle body 3, the form is shown in FIG. That is, the power lines supplied to the pilot lamps PL1 to PL6 are wired from the joint box JB to the shift operation display unit 1 and further grounded via the ground connector ECN. Next, the line for transmitting the level signal from the shift switch 2 is wired from the lower portion of the driver's seat 3a to the connector CN via the cowl side, and is wired from the connector CN to the shift operation display unit 1. The shift switch 2
The grounding line is connected to the chassis via the lower part of the driver's seat 3a. When wiring is performed in this manner, the total wiring length of the wire harness is 6 m, and the number of contacts (connection points) is 12.

C. Modified Example Next, FIG. 3 is a circuit diagram showing a modified example according to the present invention, and the same parts as those in FIG. 1 are denoted by the same reference numerals.
1 is different from the configuration of FIG. 1 in that the embodiment shown in FIG. 1 has a constant combined resistance viewed from the power source + V _C even when the switches SW1 to SW6 are operated, whereas the modified embodiment has a combined resistance value itself. Is to be changed. Also in this modification, the switches SW1 to SW are similar to the above-described embodiments.
A level signal (input voltage) corresponding to the operation of 6 is generated. Even in the configuration shown in this figure, the relationship between the reference voltage input to the comparators 1a-1 to 1a-6 and the input voltage is V _in1 > V _ref1 , V _in2 > V _ref2 , ..., V _in6.
> V _ref6 and V _in1 > V _in6 and V _ref1 > V
The resistance values of the _{voltage dividing} resistors r _{1 to} r ₆ and R _{1 to} R ₆ are determined so as to be _ref6 .

In the above modification, the vehicle body 3 is formed in the form shown in FIG.
Be wired to. That is, the pilot lamps PL1 to P
The power line supplied to L6 is joint box J
The shift operation display unit 1 is wired from B, and is grounded from the panel IP via the ground connector ECN. Next, a line for giving a level signal from the shift switch 2 is wired from the lower portion of the driver's seat 3a to the connector CN via the cowl side, and the connector CN is connected to the shift operation display unit 1. The ground line of the shift switch 2 is connected to the chassis via the lower portion of the driver's seat 3a. When wiring is performed in this manner, the total wiring length of the wire harness is 3.7.
m, and the number of contacts (connection points) is 9.

In the above-described embodiments and modifications, the resistance voltage division or the combined resistance value is changed in accordance with the switch operation provided in the shift switch 2 to generate a signal of a predetermined level, This signal level is compared with a predetermined reference voltage, and based on the comparison result, the pilot lamps PL1 to PL provided in the shift operation display unit 1 are compared.
Lighting control of 6 is carried out. Therefore, the shift switch 2 and the shift operation display unit 1 arranged apart from each other
Since it suffices that at least one wire harness is used for wiring, it is possible to reduce the number of wire harnesses wired inside the vehicle body as compared with the conventional case.

In the above-described embodiment and modification, when the level signal (input voltage) supplied to the comparators 1a-1 to 1a-6 is generated, it is different from the power source + V _B for lighting the pilot lamp. Although the power source + V _C is used, this may be shared with the power source + V _B. Further, in this embodiment and the modified example, the "switch circuit for displaying the shift operation state" is taken as an example, but the switch circuit according to the present invention is not limited to this, and in essence, the switch circuit can be used simultaneously.
It goes without saying that a switch circuit in which one or more switches are not set to the ON state can be applied to other in-vehicle electrical components.

[0026]

As described above, according to the present invention, the operating element generates a level signal according to the switch operation, and the judging circuit compares the level signal with a preset reference potential and compares them. Drive the load according to the result. Therefore, since the operator and the determination circuit are connected by at least one signal line that supplies the level signal, the number of wire harnesses wired inside the vehicle body can be reduced.

[Brief description of drawings]

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

FIG. 2 is a diagram for explaining a wiring form according to the embodiment.

FIG. 3 is a circuit diagram showing a configuration of a modified example according to the present invention.

FIG. 4 is a diagram for explaining a wiring form according to the modification.

FIG. 5 is a diagram for explaining a conventional example.

FIG. 6 is a diagram for explaining a conventional example.

FIG. 7 is a diagram for explaining a conventional example.

FIG. 8 is a diagram for explaining a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Shift operation display part, 1a-1 to 1a-6 ... Comparator (judgment circuit), 1b-1 to 1b-5 ... AND gate (judgment circuit), Tr1 to Tr6 ... Switching transistors (judgment circuit), PL1 to PL6 ... pilot lamp (load), 2 ... shift switch (operating element), SW1 to SW6 ... switch (multiple switches), R ₁ to R ₇ ... dividing resistor (resistor divider).

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Naoki Goshima 1-5-1, Kiba, Koto-ku, Tokyo Inside Fujikura Electric Wire Co., Ltd.

Claims (1)

[Claims] 1. A plurality of resistors are connected in series, one end of which is supplied with a positive power supply voltage, and the other end of which is grounded, and one end of which is connected between the plurality of resistors and the other end of which is connected. Comprising a plurality of switches connected in common, the operator for generating a level signal according to the switch operation, and comparing the level signal with a preset reference potential,
A switch circuit which drives a load according to the result of the comparison, wherein the switch circuit is connected to at least one signal line for supplying the level signal. .