JPH08121294A - Engine start detecting circuit - Google Patents

Abstract

PURPOSE: To prevent mechanical breakage in a starter motor by determining complete explosion in an engine only when an L terminal voltage of an alternator exceeds a battery voltage and continues for the predetermined time or more at the predetermined voltage or more. CONSTITUTION: When a starter signal is fed to a terminal C by remote control, a starter motor 6 is driven via an engine driving control circuit 5. On the basis of a signal from the terminal C, a switch circuit 1 is turned on, and a battery voltage in this time is stored in a voltage storage circuit 2 from a terminal B and is compared with an L terminal voltage of an alternator fed to a terminal A in the first voltage comparing circuit 3, and a high signal is fed to a microcomputer 4' if the L terminal voltage is higher. On the other hand, the L terminal voltage and a reference voltage are compared with each other in the second voltage comparing circuit 7, and a high signal is outputted when the L terminal voltage exceeds the reference voltage and continues for the predetermined time or more. In the microcomputer 4', an abnormal condition in a circuit or the like is determined when a high signal from the first voltage comparing circuit 3 and a low signal from the second voltage comparing circuit 7 are outputted, and then, processing against a malfunction is carried out.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine start detection circuit for detecting engine start, and more specifically,
The present invention relates to an engine start detection circuit for detecting an engine start in an engine starter capable of remotely starting an engine.

[0002]

2. Description of the Related Art As an engine start detecting circuit of this type, there is a utility model No. 3-51174, and its outline will be described below with reference to FIG.

That is, in FIG. 2, 1 is a switch circuit, the input side of which is connected to a battery (not shown),
It is connected to a terminal B to which the battery voltage is supplied. The input and output of the switch circuit 1 are turned on and off by a starter signal (engine start instruction signal) supplied by remote control. A voltage storage circuit 2 stores the battery voltage supplied via the switch circuit 1.

Reference numeral 3 is a voltage comparison circuit, which is the voltage storage circuit 2.
Voltage value stored in L and the alternator L (not shown)
The voltage value generated at the terminal is compared with the voltage value stored in the voltage storage circuit 2, and when the L terminal voltage becomes larger, the output is set to the high level.

A microcomputer 4 starts the engine when a high-level signal is supplied from the voltage comparison circuit 3 after a signal output from the engine drive control circuit 5 described later is supplied to the starter motor 6. When it is determined that it has been performed, the engine drive control circuit 5 outputs a signal for inhibiting the output of the signal for driving the starter motor 6.

If a high level signal is not supplied from the voltage comparison circuit 3 after the signal output from the engine drive control circuit 5 to the starter motor 6 is supplied, it is determined that the engine is not started, A signal for continuously driving the starter motor 6 is output to the drive control circuit 5.

Reference numeral 5 denotes an engine drive control circuit, which inputs a starter signal supplied by remote control to a terminal C and supplies a signal for starting the engine to a starter motor 6 intermittently a plurality of times. Further, the engine drive control circuit 5 receives a signal from the microcomputer 4 and adjusts the supply time of the signal supplied to the starter motor 6. That is,
The supply time of the second time from the first time and the supply time of the third time from the second time are adjusted to be longer and output.

That is, in the above structure, when a signal (starter signal) equivalent to turning on the ignition switch is supplied by remote control and supplied to the terminal C, the starter motor 6 is driven via the engine drive control circuit 5. .

On the other hand, the input / output of the switch circuit 1 is turned on by a signal supplied to the terminal C, the battery voltage at that time is supplied from the terminal B to the voltage storage circuit 2 and stored therein, and the stored voltage is stored. Is compared with the L terminal voltage of the alternator supplied to the terminal A, and when the engine is started and the explosion is completed, the L terminal voltage increases and a high level signal is supplied to the microcomputer 4.

The microcomputer 4 monitors the time from when a signal corresponding to the signal for driving the engine is received from the engine drive control circuit 5 until the high level signal is supplied from the voltage comparison circuit 3, When the high level signal is not supplied even after the lapse of a predetermined time, a signal for adjusting the supply time of the signal to be supplied from the engine drive control circuit 5 to the starter motor 6 next time is supplied to the engine drive control circuit 5.

[0011]

However, in the engine start detection circuit as described above, when the air conditioner, the headlight, etc. are in the on state due to the state of the engine or the environmental state, etc., the engine is overloaded. In some cases, the battery voltage during drive of the starter motor may not exceed the holding voltage even if the engine is in a complete explosion state, in which case the starter motor will continue to be driven intermittently. However, there is a problem in that it may cause mechanical damage of the.

The present invention has been made in view of such a problem, and an object thereof is to make it possible to detect the complete explosion state of the engine based on the L terminal voltage of the alternator.

[0013]

An engine start detection circuit according to the present invention includes a voltage storage means for storing a battery voltage in response to a remote engine start instruction signal, and a voltage value stored in the voltage storage means. Detected from a first voltage comparison circuit that compares the voltage generated at the L terminal of the alternator, a second voltage comparison circuit that compares the L terminal voltage of the alternator with a set reference voltage, and the first voltage comparison circuit And a microcomputer that determines that the engine is started when the output is supplied and the detected output from the second voltage comparison circuit continues for a predetermined time.

[0014]

In the engine start detection circuit according to the present invention, the L terminal voltage of the alternator exceeds the battery voltage, and L
When the terminal voltage continues to be the predetermined voltage for the predetermined time or longer, it is determined that the engine has completely exploded.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to FIG.
Note that the configuration will be described based on FIG. 1, but the same configuration as that described in FIG. 2 or equivalent components will be denoted by the same reference numerals and description thereof will be omitted, and only different portions will be described below. .

That is, in FIG. 1, reference numeral 7 is a second voltage comparison circuit, which is a voltage corresponding to the L terminal voltage of the alternator when the engine is completely detonated while the on-vehicle electric components such as headlights and air conditioners are turned on. It is set as a reference voltage, and when the L terminal voltage continues for a predetermined time or more, the output is set to a high level. Further, the microcomputer 4'has the following functions with respect to the functions of the microcomputer 4 in FIG.

That is, the microcomputer 4'determines the driving state of the engine according to the following four patterns. (1) When the high voltage signal is output from the first voltage comparison circuit 3 and the high voltage signal is output from the second voltage comparison circuit 7, it is determined that the engine is completely detonated, and the engine drive control circuit 5 is instructed. And a signal for stopping the supply of the drive signal for the starter motor 6 is supplied. (2) When the low voltage signal is output from the first voltage comparison circuit 3 and the high voltage signal is output from the second voltage comparison circuit 7, it is determined that there is a high possibility that the engine has been completely detonated, and After a predetermined time from the determination, a signal for stopping the supply of the drive signal for the starter motor 6 is supplied to the engine drive control circuit 5. (3) When the low level signal is output from the first voltage comparison circuit 3 and the low level signal is output from the second voltage comparison circuit 7, it is determined that the engine is not started and the engine drive control circuit 5 is instructed. A signal for continuing the supply of the drive signal of the starter motor 6 is supplied. (4) When the high level signal is output from the first voltage comparison circuit 3 and the low level signal is output from the second voltage comparison circuit 7, it is determined that the circuit or the like is abnormal, and the engine drive control circuit 5 is determined. On the other hand, it supplies a signal for stopping the supply of the drive signal for the starter motor 6 and outputs an alarm signal.

[0018]

As described above, according to the present invention, the driving time of the starter motor can be minimized, so that mechanical damage can be prevented.

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram of a circuit configuration of a conventional wireless engine starting device.

[Explanation of symbols]

 1 Switch Circuit 2 Voltage Storage Circuit 3 First Voltage Comparison Circuit 7 Second Voltage Comparison Circuit 4'Microcomputer 5 Engine Drive Control Circuit 6 Starter Motor

Claims (1)

[Claims] 1. A voltage storage means for storing a battery voltage in response to a remote engine start instruction signal, and a first voltage value comparison means for comparing the voltage value stored in the voltage storage means with the voltage generated at the L terminal of the alternator. A voltage comparison circuit, a second voltage comparison circuit for comparing the L terminal voltage of the alternator with a set reference voltage, a detection output from the first voltage comparison circuit, and a second voltage comparison circuit from the second voltage comparison circuit. An engine start detection circuit, comprising: a microcomputer that determines that the engine has been started when the detection output continues for a predetermined time.