JPH0337372A - Vehicle starter protection device - 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 is a starter protection device for a vehicle, in particular, a starter protection device that automatically starts the starter when the engine is started and the engine speed reaches a set value. to stop the
The present invention also relates to a starter protection device for a vehicle that prevents a starter from accidentally jumping into the vehicle.

[Conventional technology]

Generally, when starting an engine, the starter relay is activated by closing the manual key switch.
Start the starter via the contacts of the starter relay above,
The engine is started by meshing a pinion gear on the starter side with a ring gear on the engine side. After confirming that the engine has started, opening the first manual key switch turns off the power to the starter, the pinion gear protruding from the starter returns to its original position, and the starter rotates due to inertia before coming to a complete stop. That is, the driving force of the starter is transmitted to the engine through the meshing of the pinion gear and the ring gear to start the engine, and the starter returns to the stopped state.

However, if the above mentioned starting is completed and the engine is rotating normally, or if the engine fails to start for some reason and the starter is rotating by inertia, if the manual key switch is closed by mistake, the starter will start. Either the pinion gear on the side or the ring gear on the engine side will collide with each other in a rotating state, and there is a risk of damaging each of the gears.

Therefore, when the engine has successfully started and started rotating, it is necessary that the starter will not start even if the manual key switch is accidentally closed, and if the engine fails to start for some reason, the starter's inertia will A protection device is required that will prevent the starter from starting even if the manual key switch is closed until rotation stops.

As a conventional voltage detection type vehicle starter protection device, the one shown in FIG. 2 has been used.

In the figure, 1 is a manual key switch, 2 is a starter relay, and excitation coils 2-1. Normally open contact 2-2. It consists of diodes 2-3. 3 is a relay drive transistor, 4 is a control transistor, and 5 is a deterrent control circuit, in which the relay drive transistor 3 is activated during inertia rotation of the starter.
The OP amplifier 51. which operates as a comparator controls the OFF state. Diodes 52, 53. It consists of a capacitor 54 and resistors 55 to 59. Reference numeral 6 denotes a control circuit which controls the control transistor 4 to be turned on or off in accordance with the voltage generated by the alternator as the engine rotates, and includes an OP amplifier 61.6 which operates as a comparator. Inverter 62. diode 63
．． It is composed of capacitors 64 to 67 and resistors 68 to 76. 10 is a constant voltage diode, and 11 is a diode.

12.13 represents resistance.

The vehicle starter protection device shown in Figure 2 has the following three functions: (1) Prevents the starter from jumping in while the engine is rotating (2) Prevents the starter from jumping during starter inertia rotation (3) When the engine starts and reaches the set rotation speed It is equipped with an automatic starter disconnection function.

The function (1) above is to receive the generated voltage (generated signal) of the alternator at the R terminal, and when the average voltage is 13V or more, the starter will not operate even if the manual key switch l is turned on.

When the engine is rotating normally, the alternator is connected to the R terminal of the control circuit 6 to maintain a voltage (for example, 1
3V) is input. This holding voltage is diode 6
3. The capacitors 64 and 65° are converted into direct current by resistors 69 to 71, and the control transistor 4 is kept in an on state at all times via an OP amplifier 61 and an inverter 62. Therefore, the relay drive transistor 3 that drives the starter relay 2 is always off while the engine is rotating normally, and even if the manual key switch 2 is closed, the starter relay 2 is not energized and is connected to the starter. Battery voltage is not always supplied to the D contact that is connected.

Function (2) above receives the inertia rotation signal of the starter at the C terminal of the inhibition control circuit 5, and when the voltage is higher than the minimum voltage (e.g. O, lV) indicating that the starter is inertia rotation, the manual key switch l Even if the starter is turned on, the starter will not operate.

When the engine reaches normal rotation, the pinion gear on the Stark side and the ring gear on the engine side are separated, and when the starter returns to its original position, or when the starter returns to its original position due to engine starting failure, etc. continues its rotation due to inertia. This inertial rotation causes the starter to become a generator, and a voltage proportional to the inertial rotation speed is input to the C terminal of the inhibition control circuit 5 as an inertial rotation signal of the starter. Voltage 9 just before the inertia rotation of the starter stops
For example, when inputting an inertial rotation signal of approximately 0.1 V or more, O
The output of the P amplifier 51 is kept at a low level and the relay drive transistor 3 is turned off. Therefore, as in the case (1) above, even if the manual key switch 1 is turned on during the inertia rotation of the starter, the starter will not jump.

The function (3) above operates when the engine starts and the load on the starter becomes lighter, and when the voltage manually applied from the alternator to the R terminal of the control circuit 6 reaches the automatic disconnection voltage 9, for example 21V, the manual key switch 1 is turned on. The purpose of this is to automatically disengage the starter even if the

While the engine is being rotated by the starter, the voltage input from the alternator to the R terminal of the control circuit 6 is low, but when the engine starts and begins to rotate by itself, the voltage of the power generation signal from the alternator input to the R terminal increases. It gets expensive. When the voltage that ensures that the engine is fully started, i.e. the withdrawal voltage 1, for example 21V, is reached, the OP
The output of the amplifier 61 becomes low level, turning on the control transistor 4 via the inverter 62. As a result, the relay drive transistor 3 is reversed from the on state to the off state, and even if the manual key switch 1 is turned on, the starter relay 2 is deenergized, and the battery voltage supplied to the starter via contacts B and D is removed. Be cut off. Therefore, the starter leaves. In other words, automatic withdrawal is performed.

(Problem 1 to be solved by the invention) The generated voltage of the alternator is shared with the circuit that charges the battery, and the automatic disconnection voltage of the starter is set to a relatively high voltage of 21V as explained above. Therefore, depending on the charging state of the battery, that is, due to the influence of the battery side, the above-mentioned automatic disconnection voltage of 21V may not be input to the R terminal of the control circuit 6 even though the alternator is generating a predetermined voltage. , there was a risk that the starter's automatic disconnection function would not work. However, if the disconnection voltage is lowered any further, it approaches the holding voltage of 13V while the engine is rotating, and if the 1 manual key switch l is turned on, there is a possibility that the starter will jump back in after automatic disconnection, as shown in Figure 2. It was also not possible to lower the detachment voltage with the circuit shown in . Note that since a voltage of 6V may be applied to the R terminal of the control circuit 6 when the engine is stopped, it has been impossible to lower the holding voltage of 12V while the engine is rotating due to this relationship.

The 5-circuit configuration was complicated, and the board also tended to be large.

The present invention has been made in view of the above-mentioned problems, and has a circuit configuration that can reliably satisfy the three functions (1), (2), and (3) above, reduce the above-mentioned disconnection voltage, and The purpose of the present invention is to provide a starter protection device for a vehicle that is easy to use and has a compact board.

[Means to solve the problem]

In order to achieve the above object, two starter protection devices for a vehicle according to the present invention include a starter relay that supplies battery voltage to the starter by closing a manual key switch, a relay drive transistor that controls the operation of the starter relay, and a relay drive transistor that controls the operation of the starter relay. A control transistor that controls on/off of the transistor, an inhibition control circuit that controls the relay drive transistor to be off during inertia rotation of the starter, and a control transistor that turns the control transistor on or off according to the voltage generated by the alternator generated by engine rotation. The starter is equipped with a control circuit to control the automatic H111, WI'
In a starter protection device for a vehicle, which performs control to prevent starter from jumping during inertial rotation of the starter and engine rotation.

The control transistor is controlled to be turned on by the voltage generated by the alternator, and a latch circuit is provided to hold the 111111) transistor in the on state when the relay drive transistor is turned off. This will be explained below with reference to the drawings.

〔Example〕

FIG. 1 shows the circuit configuration of an embodiment of a starter protection device for a vehicle according to the present invention, and the difference from FIG. 2 is that a latch circuit 9 is newly provided.

and the configuration of the control circuit 8 with a new reference numeral.

The latch circuit 9 consists of resistors 91 and 92, and the control circuit 8
is a constant voltage diode 81. It consists of a diode 82, a capacitor 83 and a resistor 84.85. When a voltage of, for example, 12V is applied to the R terminal of the control circuit 8,
Constant voltage diode 8 that turns on the control transistor 4
1 has been selected.

Now, when the generated voltage of the alternator of 12 V or more is input to the R terminal of the control circuit 8, the control transistor 4 is turned on for the above-mentioned reason, and the output of the OP amplifier 51 becomes low level via the diode 82. Also, the relay drive transistor 3 is turned off, and the collector potential of the relay drive transistor 3 rises. As a result, a base current is prepared to flow into the control transistor 4 via the resistor 91 of the launch circuit 9, and the control transistor 4 is maintained in an on state. Since the control transistor 4 is maintained in the on state via this resistor 91,
The detachment voltage for the function (3) above can be lowered to about 12V, and the automatic detachment function (3) will work reliably even if the battery is in a poor state of charge.

Also, after the engine starts and the starter automatically disengages,
Even if the detachment voltage 12V is close to the engine rotation holding voltage 13V, the control transistor 4 is maintained in the on state via the resistor 91, so that the starter is prevented from jumping back in after automatic detachment.

Note that the function (2) above is the same as the conventional circuit, so
There is no need to explain the function as it is fulfilled.

Since the control circuit 8 can approach the detachment voltage and the holding voltage during engine rotation, the constant voltage diode 81
can be used, the circuit configuration is simplified, and even if the voltage input to the R terminal of the control circuit 8 is an average value voltage, it can be detected. The voltage generated by the alternator can also be detected.

〔Effect of the invention〕

As explained above, according to the present invention, by providing a latch circuit, the disconnection voltage for automatic disconnection of the starter can be lowered, and the reliability of the automatic disconnection function is improved.

Since the voltage generated by the alternator that is input to the control circuit can be detected as either an AC or DC voltage, it is possible to handle the output of either an AC or DC alternator.

In addition, contact with the holding voltage during rotation of the piezovoltage engine is allowed, so there is no need to use a high-precision comparator like in conventional circuits, and it can be replaced with a constant voltage diode, simplifying the circuit configuration. , the substrate becomes smaller.

[Brief explanation of drawings]

FIG. 1 shows a circuit configuration of an embodiment of a starter protection device for a vehicle according to the present invention, and FIG. 2 shows a conventional circuit diagram. In the figure, l is a manual key switch, 2 is a starter relay, and 3 is a manual key switch.
is a relay drive transistor, 4 is a control transistor, and 5 is a relay drive transistor.
6 is an inhibition control circuit, and 6 is a control circuit. 8 represents a control circuit, and 9 represents a latch circuit.

Claims (1)

[Scope of Claims] A starter relay that supplies battery voltage to the starter by closing a manual key switch, a relay drive transistor that controls the operation of the starter relay, a control transistor that controls on/off of the relay drive transistor, and a starter relay that supplies battery voltage to the starter by closing a manual key switch. The starter is equipped with an inhibition control circuit that controls the relay drive transistor to be turned off during inertia rotation, and a control circuit that controls the control transistor to be turned on or off according to the voltage generated by the alternator generated by the rotation of the engine. In a vehicle starter protection device that performs separation control as well as starter jump prevention control during starter inertia rotation and engine rotation, the above control transistor is controlled to be turned on by the generated voltage of the alternator, and the relay drive transistor is turned off. Taking this as an opportunity, a starter protection device for a vehicle is characterized in that it is provided with a latch circuit that keeps the control transistor in an on state.