JPH04318281A - Starter motor control device - Google Patents

Abstract

PURPOSE:To prevent a starter motor from its overrunning. CONSTITUTION:When a neutral switch 5 is placed in a closed condition and fixed to a 'START' position by trouble of a key switch 4, a starter relay 3 is actuated to start a starter motor 7. When a capacitor 25 is charged to increase charge voltage larger than divided voltage after a fixed time, an output of a comparator 21 becomes '0' level to stop action of the starter relay 3 by placing a transistor 23 in non-conduction. When the neutral switch 5 is tripped, an output of a flip flop 11 is inverted to decrease the divided voltage by conducting a transistor 22. When the neutral switche is reclosed at the time of vehicle stop, the starter relay is actuated, but the charge voltage of the capacitor exceeds the lowered divided voltage in a shorter time to stop the starter relay in a short time.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a starter motor control device, and more particularly to a control device that can effectively prevent starter motor overrun.

0002

[Prior Art] As a control device of this type, the U.S. Pat.
Publication No. 9644 describes the starter switch and starter motor.
A normally closed relay contact is interposed between the two terminals, and if the starter switch is kept on for a certain period of time required for the initial start of the engine, the transistor that excites the relay coil becomes conductive due to charging of the capacitor. It has been proposed that a relay contact is opened to stop the starter motor.

0003

However, in automatic vehicles, in order to enable the starter motor to start only when the shift lever is in the neutral position or the parking position, it is necessary to START”
A switch (neutral switch) that detects the neutral position and closes the switch is often connected in series with the contact (starter switch). In addition, in manual transmission vehicles in North America, the key switch is set to "ST" to enable the starter motor to start only when the clutch is depressed.
A switch (clutch switch) that detects clutch depression and closes the clutch is connected in series to the ART contact.

[0004] In such vehicles, the key switch becomes "ST" due to malfunction such as failure of the key to return or welding of the contacts.
When the shift lever is fixed at the ``ART'' position, if the conventional control device described above is used, the shift lever will be moved to the new position when the vehicle is temporarily stopped, etc.
Whenever the neutral position is reached, the neutral switch is frequently closed and the control device is energized and activated, causing the starter motor to rotate for a certain period of time, and repeated overruns may cause burnout of the motor.

[0005] The present invention solves this problem, and eliminates the risk of motor burnout even when used in vehicles that are equipped with a switch that controls starter operation in series with a starter switch, such as an automatic vehicle. It is an object of the present invention to provide a control device for a starter motor that does not require a starter motor.

[0006]

[Means for Solving the Problems] The configuration of the present invention will be explained with reference to FIG. 3. A starter command signal is output when a predetermined vehicle condition is satisfied with the key switch selected as the "START" contact. and the key switch “ON”
When the rear starter command signal is input for the first time, the starter activation signal is output for a predetermined period of time, and when the starter command signal is input for the second time or later with the key switch "ON", the starter is activated for a shorter time than the predetermined time. means for outputting a signal;
means for inputting the starter starting signal to rotate the starter motor; and means for resetting the number of inputs of the starter command signal when the key switch is selected as a contact other than the "START" contact. Equipped with

[0007]

[Operation] In this configuration, the key switch's "STA"
When a predetermined vehicle condition is satisfied in a state where the return from the "RT" contact is poor, a starter command signal is output each time. When the starter command signal is input for the first time, the starter start signal output means outputs the starter start signal for a predetermined time sufficient for the initial engine start, and from the second time onwards, it outputs the starter start signal for a predetermined time sufficient to restart the engine. The starter motor is rotationally driven by outputting a starter activation signal for a shorter period of time. Thus, the star
As a result, the rotation of the motor is suppressed to a minimum amount of time, thereby preventing burnout and the like.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a circuit diagram of a control device in which the present invention is implemented as a hard circuit. The control device includes a counter circuit 1 centered around a JK flip-flop 11, a comparator 21, transistors 22 and 23, and a Zener diode 2.
4, a timer circuit 2 comprising a capacitor 25, etc., and a starter relay 3. The Zener diode 2 is connected to the non-inverting terminal of the comparator 21.
A voltage obtained by dividing the Zener voltage of No. 4 by a resistor is inputted, and this divided voltage becomes lower when the transistor 22 becomes conductive. The above capacitor 2 is connected to the inverting terminal of the comparator 21.
5 charging voltage is input.

4 in the figure is a key switch, and a neutral switch 5 is connected in series to its "START" contact.
is connected. The neutral switch 5 is closed when the shift lever is in the neutral position or the parking position. The vehicle battery 6 is connected to the common contact of the key switch 4, the contact 32 of the starter relay 3, and the starter motor.
It is connected to a contactor contact 72 in the contactor 7.

The operation of such a control device will be explained below. When the key switch 4 is in the "OFF" position, the diode 26
and S of the flip-flop 11 via the inverter 12.
A "0" level signal is input to the terminal, and the output connected to the base of the transistor 22 becomes "0" level, so that the transistor 22 is non-conductive. Turn key switch 4 to “O”
When set to "N", the capacitor 25 is in a discharged state, so
The output of the comparator 21 becomes "1" level, and the transistor 23 becomes conductive. “
Although an "O" level signal is input, there is no change in the output.

When the shift lever is set to neutral or park and the key switch 4 is set to the "START" contact, the starter relay is activated via the neutral switch 5.
The coil 31 of No. 3 is energized, its contact 32 is closed, and the contactor coil 71 of the starter motor 7 is energized. The contactor contact 72 is then closed and the motor 7 is started. At this time, a "0" level signal is input to the CL terminal of the flip-flop 11 via the inverter 13.
The output state of flip-flop 11 does not change.

Charging of the capacitor 25 is started, and its charging voltage gradually increases until it becomes higher than the divided voltage of the Zener voltage of the Zener diode 24 after a predetermined time period sufficient for initial starting of the engine has elapsed. As a result, the output of the comparator 21 is inverted to "0" level, and the output of the transistor 23 is inverted to "0" level.
becomes non-conductive, and the operation of starter relay 3 is canceled.
Starter motor 7 stops. That is, even if the key switch does not return from "START", the starter motor is forcibly stopped after a predetermined period of time to prevent overrun.

When the shift lever leaves neutral while the key switch remains in the "START" position, the switch 5 opens, the capacitor 25 discharges, and the inverter 13
A "1" level signal is input to the CL terminal of the flip-flop 11 via the CL terminal of the flip-flop 11. As a result, the output of the flip-flop is “
1'' level, transistor 22 becomes conductive, and the divided voltage input to comparator 21 is lowered.

In this state, the key switch is "STA".
RT", the vehicle stops, and then shift the shift lever to the new position.
When set to the tral position or the parking position, the neutral switch 5 closes and the coil 31 of the starter relay 3
The starter motor 7 is started by being energized again, and at the same time, recharging of the capacitor 25 is started. The motor 7 is rotated until the charging voltage exceeds the divided voltage.
Since the divided voltage at this time is lower, the timer time is set short, and the rotation time will be changed if the engine stalls when key switch 4 is normal or if the engine cannot be started with one key operation. This minimizes the time required to restart the engine in the event of an accident.

After that, the starter motor 7 is rotated every time the shift lever is returned to the neutral position or the parking position while the switch remains in the "START" position, but the output state of the flip-flop 11 does not change. Therefore, the rotation time can be kept short. The above flip-flop 11
maintains its output state until the key switch 4 is turned OFF.

The functions of the control circuit described above can also be realized by computer software, and a program flowchart in this case is shown in FIG.

In the figure, when the key switch 4 is in the "ON" position (step 101), if the "START" line is energized (starter switch and neutral switch are ON) (step 102), the starter relay is turned on. 3 conducts and rotates the starter motor 7 (
Step 103). Determine whether or not this is the first time power is being applied from the "START" line (step 104), and if it is the first time, set a long timer (step 105), and if it is the second time or later, set a short timer (step 106). do.

If the power from the "START" line is cut off (starter switch or neutral switch is OFF) during the timer time, the starter relay becomes non-conductive, but even if it remains energized, the starter relay will be turned off when the timer time elapses. - Make the tally relay 3 non-conductive (steps 107 and 10)
9), check whether the key switch 4 is in the "OFF" position (step 110), and if it is in the "OFF" position, press "START".
Clears the memory that counts the number of times the line is energized (the number of times the starter switch or neutral switch is turned on) (step 111).

The above embodiments are not limited to automatic vehicles, but can be similarly applied to manual shift vehicles by providing a clutch switch or the like that is activated when the clutch is depressed in place of the neutral switch.

Here, one way to prevent repeated overruns is to detect the engine speed and prevent the starter from being re-energized if the engine speed is above a predetermined value (engine is running). However, in this case, it is necessary to use a signal such as the engine speed, and the device becomes expensive. This embodiment is advantageous in that this is not necessary.

[0021] Furthermore, from the viewpoint of ensuring engine startability, it is necessary to set the starter's energization time to be long.
If you set the starter energization time to be the same each time, a problem will occur. In other words, when starting an engine at low temperatures, it is difficult to start the engine and it is necessary to turn the power on for a long time, whereas when restarting the engine after stalling, etc., when the engine is warm, it is only necessary to turn on the power for a short time, and it is necessary to turn on the power for a long time. This results in unnecessary power consumption and equipment damage. Therefore, in this embodiment, the starter energization time is set in consideration of this point, and the starter can be driven appropriately without impeding engine startability.

[0022]

[Effects of the Invention] As described above, according to the control device of the present invention,
Since the starter motor is not rotated unnecessarily for a long time, burnout caused by repeated overruns of the starter motor can be effectively prevented without deteriorating the restartability of the engine. Can be done.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of a control device in an embodiment of the present invention.

FIG. 2 is a program flowchart of a control device in another embodiment of the present invention.

FIG. 3 is a claim correspondence diagram of the present invention.

[Explanation of symbols]

1 Counter circuit 2 Timer circuit 3 Starter relay 4 Key switch 5 Neutral switch 6 In-vehicle battery 7 Starter motor

Claims (1)

[Claims] 1. Means for outputting a starter command signal when a predetermined vehicle condition is satisfied with the key switch selected as the "START"contact;
” When the starter command signal is input for the first time, the starter activation signal is output for a predetermined period of time, and the key switch remains “ON”, and when the starter command signal is input for the second time or later, the starter activation signal is output for a predetermined period of time shorter than the predetermined time. means for outputting a starter start signal; means for inputting the starter start signal to rotationally drive the starter motor;
A starter motor control device comprising means for resetting the number of times a starter command signal is input when a contact other than a contact is selected.