JPS5841267A - Glow plug control system - Google Patents

Abstract

PURPOSE:To enable to eliminate the waste of an electric power and protect a battery by a method wherein conducting circuits for preheating upon starting of an engine and after-glow after the starting of the engine are switched and the conducting period of time therefor is controlled. CONSTITUTION:When a key switch 1 is thrown in order to operate the engine, a transistor 13 becomes ON before the starting of the engine while becomes OFF after the starting thereof and thereby energizing a relay 10 only on a time before the starting of the engine and conducting glow plugs 2a-2d to heat them. An after-glow control circuit 12 energizes a second relay 9 only when the first relay 10 is being energized and supplies an electric current having comparatively smaller value than the neutral point of an alternator 5 to the glow plugs 2a-2d until the speed of the engine has arrived at a threshold level. According to this method, the control circuit, capable of eliminating the waste of electric power consumption and stopping the after-glow conduction automatically, may be obtained.

Description

[Detailed description of the invention] After starting the diesel engine, especially when the engine is cold, energizing the D4 plug is effective in reducing noise, especially idle noise, and reducing Ha in the exhaust gas. This is well known.

In this case, it is not necessary to supply the same power to the gray plug as before starting; rather, if the battery voltage is supplied for a long period of time, power consumption will be excessive, and in addition, conventionally, a voltage drop resistor is not used. By energizing the green plug, the above 77 tada p- is carried out.

However, using a resistor in this way has the disadvantage that the power consumption of this resistor is wasted.

Therefore, it is an object of the present invention to provide a control device that can realize after-dark energization without unnecessary power consumption. Furthermore, it is another object of the present invention to provide a control device that can automatically stop energization.

In order to achieve these objectives, we focused on the fact that the voltage generated at the neutral point of the alternator driven by the engine according to the present invention can provide a moderate amount of power to the green plug. The present invention is characterized in that an energizing circuit for supplying current is provided, and a switch means provided in the energizing circuit is automatically opened by a control means for determining termination of energization.

As exemplified in the following explanation, information such as control parameters indicating control parameters indicating necessary conditions for aftergoo in the control means company, and time limits set in anticipation of such necessary conditions and constraint conditions, etc. The energization time can be determined by

FIG. 1 shows a first embodiment of the invention. In the figure, g&-la are preheating gray plugs attached to each cylinder of the diesel engine, and these glow plugs are energized for both the purpose of preheating when starting the engine and for 77 tar glow after starting.

Glow plug B a N! I di h A device that generates heat when energized, and its power source is a direct current battery installed in a car 8
and an alternator (three-phase alternator) b. Alternator 6#iAs is well known, it operates by receiving rotational driving force from the output shaft of the engine, and the stator coil 5
a to 5c [generates three-phase alternating current, rectifier diode 4 a
A charging current is supplied to the battery 8 via N4t.

As is well known, a rotor coil and voltage adjustment IT are attached to adjust the battery voltage.
Here, detailed explanations and illustrations of the company will be omitted.

According to the present invention, a power supply line to the green plug g a Ng IL, a line from the battery 3 via the contact point of the 19th relay 10, and a line from the neutral point of the alternator b to the 39th relay 9
A line passing through the contact point is provided. The first relay 10 is connected by the preheating control circuit 11 and by the third relay 911 after-heating control circuit 1BK.
The glow plugs B&~2a are energized by selectively using the two lines that are deenergized. These preheating control circuit 11 and afterglow control circuit 1 s h are supplied with power from the battery 8 when the engine key switch l is turned on and are activated, and each determines whether to turn on or off the transistor 18.14 for driving the relay 10.9. .

It is comprised of a preheating control circuit 11a, an engine start detector 15, a switch circuit 16 responsive to its output, and a signal inversion circuit (inverter) lf.

The starting detector 16 is a well-known contact type voltage regulator (not shown) attached to the alternator b.
A charge lamp relay responsive to the voltage developed at the neutral point 8 of ←# can be used. The output terminal of this charge lamp relay is called the so-called "SH" terminal, and is at the ground level before the engine starts, and when the engine starts, the alternator 5 starts generating electricity, and when the engine speed reaches a predetermined level, When the point voltage reaches a certain level, the charge ramp relay is energized to produce an output that is at the battery supply voltage level.

The switch circuit 16 receives human power from the start detector 16, and when the power is at the ground level and the key switch 1 is turned on, it becomes high level, and when it is at the power supply voltage level, it outputs to the transistor 18, which becomes low level. give. Therefore, when the key switch 1 is turned on to operate the engine, the transistor 13 is turned on before the engine starts, and is turned off after the engine starts, and the relay 10 is turned on only before the engine starts. to strengthen For this reason, glow plug 2a
w B a is from the battery 8 to the key switch l and the first
Electricity is applied through the closed contact 1 of the relay and the engine is heated to the temperature required to start the engine. In order to start the engine, one starter contact (not shown) is turned on at the right time, the starter motor rotates, and the engine starts.
The relay IO is deenergized and the power supply to the battery JlfPh and the battery plug z&~24 is stopped.

The after-low control circuit 12 controls the energization of the second relay 9 only when the first relay 10 is de-energized, and determines the energization period. This control circuit 1 ink engine speed detector 1
B, frequency-voltage conversion circuit 19, and voltage comparison circuit 10
and an AND circuit 21.

The detector 18 uses a switching element, such as a D-reed switch, which opens and closes in synchronization with the rotation of the engine output shaft, and generates a waveform in the pulse signal conversion circuit 19, which generates a value proportional to the frequency. is converted into a DC voltage.

This DC voltage is compared in magnitude with a threshold level in a voltage comparison circuit BO which determines a reference threshold level. This threshold level is determined corresponding to the idle value of the engine rotational speed, and the comparator circuit 20 outputs a high level when the engine speed is slightly higher than the idle value and below the threshold level, and a high level when the engine speed is slightly higher than the idle value and below the threshold level. An output signal having a 4-level is input to an AND circuit glIIC.

The AND circuit gl is connected to the inverter l? of the other preheating control circuit 11. A signal indicating whether or not the engine has been started is input from , and according to the AND logic, if the engine has started and is near the idle value, * is a high level; When the speed greatly exceeds the idle value t, an output signal that becomes -level is given to the transistor 14.

Therefore, turning on transistor 14 energizes eighth relay 9 only when the engine is operating at a speed near the idle value.

The apparatus described in this first embodiment operates as follows. First, in order to fully start the engine, close the key switch l.
The first relay 10Th is energized and the glow plug! ! L
-111C*L battery sh and other relatively large gvh value electric m
is supplied and heated rapidly.

Thereafter, when the starter switch is closed to start the starter and the engine starts rotating, a low-level signal is generated in the preheating control circuit 11, and the first relay 10 is deheated.

When the engine is started and the engine speed has not reached the threshold level, for example, 10001000 rpm, the aftergushy control circuit 1
2, the second relay 9 is energized. As a result, a relatively small current of one value is supplied from the neutral point of the Guta-Butegu 9&~gaa alternator 6, creating an afterglow.

By energizing the group lug in an engine in an idling state in this way, the effects of noise reduction and exhaust gas purification are exhibited.

When the accelerator pedal is depressed to increase the engine speed and the engine speed exceeds the idle value, the third relay 9 is deenergized and the afterglow is also stopped. This prevents an unnecessary increase in power consumption due to energizing the dashi plug for a long period of time. In addition, since the engine speed is relatively high, there are few problems with the noise and exhaust gas mentioned above, so there are no practical disadvantages.
.

In the first embodiment, the afterglow control circuit 18 controls the activation and deactivation of the second relay 9 in response to the engine speed, but in order to obtain the same effect, the accelerator pedal There is an electrical means for detecting the amount of depression of the
Electrical means may also be used to detect the traveling speed of company vehicles.

The second circular shows the eighth embodiment of the present invention, and the differences from the example in FIG. 1 are the configuration of the first relay 1G, the configuration of the preheating control circuit 11 and the afterglow control circuit 1m. be. The 19th relay 1011 has an ever-dark contact, and only in that situation, the transistor 14 drives the eighth relay 9 with the output of the afterglow control circuit 18.
It's happening. Therefore, the preheating control circuit 11 does not have the inverter f--explained as an example in FIG. 1, and the afterglue control circuit 11a does not have an AND circuit.

Afterganda - Control circuit 11iH1 Water temperature detector 8B and voltage comparison circuit to drive the 8th relay 9 depending on the engine temperature! It consists of 18.

The water temperature detector SS#i consists of a thermistor attached to the cooling water jacket of the engine, and generates a DC voltage whose value corresponds to the cooling water temperature. It is compared to the Threshi Sundrepel. Thresh! The iF# level is set corresponding to, for example, tf40''OK, and the transistor 14fIc provides an output signal which becomes a low level when the water temperature is lower than that level, and a high level when it becomes high.

By turning on this equipment company's key switch l, the dashi plug S&~B is connected via the normally open contact of the first relay 1G.
6 is turned on to preheat 1kL, and the engine cooling water temperature for starting is 4.
The neutral point of alternator B is energized through the 8th relay 9 until it reaches 0'' OK.
to do.

The engine water temperature corresponds to the temperature of the engine, and this device aims to reduce noise and purify exhaust gas by performing after gray when the engine is sufficiently relaxed.

'&O, engine temperature It is possible to obtain the same effect by measuring not only the cooling water temperature but also the temperature of parts that have a correlation with the engine temperature, such as the engine surface temperature or lubricating oil temperature. . Alternatively, a thermistor and a voltage comparator contact type thermostat may be used instead.

FIG. 8 shows a third embodiment of the present invention. In this eighth embodiment, the power supply capacity of the battery 8 is detected, and when the power supply capacity is sufficient, the eighth relay 9 is energized, and when it is insufficient, the eighth relay 9 is deenergized. be. That is,
When the engine is running and almost no other electrical loads are being used, the battery terminal voltage may be below the set value, even if i
Fl! 8th relay GYt is energized and aftergoo current is supplied from the neutral point of alternator b to glow plugs B&~BILK.

As shown in the figure, the afterglow control circuit 13 includes a battery voltage voltage divider window 4 and a constant voltage voltage divider circuit 86 using a Zener diode s6, and a voltage comparison circuit 119 compares both voltages. By doing so, it is determined whether the battery voltage value is higher than 117. And comparison circuit 8? The output signal butterfly is used for energizing and deenergizing the 89th relay 9 via an AND circuit 88 which has the same role as the reference numeral 81 in FIG.

First, instead of detecting the value of the battery voltage, the power supply capability can also be measured by detecting the value of the load current flowing out from the battery. For this purpose, for example, by connecting a microresistor in series with the battery, the voltage at its terminal can be amplified and compared with a reference voltage.

4th Circular A fourth embodiment of the present invention is shown. In this fourth embodiment, the third relay 9 is energized for a certain period of time, for example, several minutes after the forest engine is started, and after several minutes of 77 tag p-, the 39th relay 9 is energized. to stop the after gray.

In the figure, afterglue control circuit 1ift, (first
A trigger circuit that generates a trigger pulse based on the rising edge of the start detection signal of the level (given by the inverter 1tiIh shown in the figure)! ! 9 and a monostable Lr multi 80 that generates a high level signal for a certain period of time with its output pulse.
At the same time, the monostable multi gives a high level output to F range X#14. Therefore, for several minutes after startup, the glow plug Ra NB tl K is energized from the neutral point 8 of the alternator 6 to the L1 afterglow field. After a few minutes, the low level output of the monostable multi-80 (inverted,
The second relay 9 is deenergized and stops the aftergage p-.

In each of the embodiments described above, voltage comparison circuit No.

28.B? Chattering can be prevented by setting appropriate hysteresis using a known method.

In addition to the parameters exemplified in the above-mentioned embodiments, the present invention detects the noise generated by the engine in the engine room using a microphone, or detects the vibration of the engine, thereby detecting the noise generated by the engine when the vibration is large. The presence or absence of energization may be determined so as to energize for the afterglow of the horseflies.

1+, two or more of the exemplified parameters may be used in combination, and the presence or absence of energization may be determined based on the logical sum condition or logical sum condition.

As described in detail above, the present invention changes the current supply circuit to the glow plug for preheating during engine activity and for afterglow after engine startup, and connects the power supply for afterglow to the neutral point of the alternator. Since the electricity is supplied from
This has an excellent effect in that it eliminates wasted power and helps protect the battery.

[Brief explanation of the drawing]

1, 2, 8, and 1 are the 11th embodiment of the present invention, respectively.
FIG. 7 is an electrical wiring diagram showing eighth, third, and fourth embodiments. l...engine key switch, gaNga...glow plug, S...battery, 6...alternator,
8...neutral point, 9...8th relay, 10...-1st relay. 11-・Preheating control circuit 1, 1 g-・Afterglow control circuit e16-Start detector, 18-・Engine speed detector, 8t・・Water temperature detector, 8o・・Monostable multi. Representative Patent Attorney Takashi Okabe 393

Claims (1)

[Scope of Claims] (13III! K An energizing circuit for supplying current from the neutral point of the alternator driven by the engine to the group lug mounted thereon; a switch means for opening and closing the energizing circuit; A green plug control device comprising: control means for controlling the switch means in order to control the energization time of the Dalet-Prada in the energization circuit; (2) control means for the control means to indicate the operating state of the engine The green plug control device according to claim 1, wherein the energization is mii* in response to a parameter.(8) The green plug control device according to claim 1, wherein the control parameter is the rotational speed of the engine. (6) The gree plug control device according to claim 3, wherein the control parameter is the operating speed of a load mechanically moved by the engine. Range 818
Gray Prada control device of the 8th article war. (6) The gree plug control device according to claim 2, wherein the control parameter is the temperature of cold water in the engine. ()) The globe ladder control device according to claim 3, wherein the control parameter is the temperature of engine oil of the engine. (8) The green plug control device according to claim 8, wherein the control parameter is the magnitude of vibration of the engine. (9) The control parameter is the magnitude of noise of the engine. The green plug control device according to claim 8. (The control means is adapted to control the energization in response to a 11111 parameter indicating the state of the electrical load of the alternator.) The glow plug control device according to claim 1. (n) The glow plug control device according to claim Φ, wherein the control parameter is the magnitude of a terminal voltage of a storage battery connected to the alternator. The glow plug control device according to claim 1, wherein the control parameter is the magnitude of the current supplied from the storage battery connected to the alternator. 2. A glow plug control device according to claim 1, wherein said glow plug control device controls said energization in response.