JPS59122779A - Electrification controller of glow plug - Google Patents

Abstract

PURPOSE:To prevent a decrease of glow plug temperature caused by a drop of battery voltage and the cooling action due to fuel injection, by controlling the electrification of a glow plug by a correcting circuit, which promotes the synchronization of a heating characteristic, when an engine is started. CONSTITUTION:When a starter motor is operated during an output time limit t1 of a timer T1, the time limit is extended to a time limit t2. During operation of the starter motor after elapsed the time of these time limits, a low level output time limit t4 and a high level output time limit t3 are repeated. In this way, insufficient temperature is eliminated when an engine is tried to be started before the temperature of a glow plug increases to its necessary level, and a temperature decrease of the glow plug, arising from cooling of the glow plug due to fuel injection and a drop of battery voltage in accordance with electrification of the starter motor, is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a glow plug energization control device used to assist in starting a diesel engine.

An energization control device using a rapid heating type glow plug includes a rapid temperature increase relay 1 that supplies a large current to the glow plug;
It consists of a temperature maintenance energization relay 2 that energizes the glow plug via a current control resistor, and an energization control circuit that controls the relay 1 and the relay 2. Supplying a large current to the glow plug to rapidly raise the temperature of the glow plug to the required temperature sufficient for starting the engine, and then applying electricity through the relay 2 to maintain the glow plug at the required temperature for a predetermined time. This helps the engine start quickly and smoothly.

However, in the conventional glow plug energization control device, the battery voltage decreases when the engine starts, the fuel injection I,
Since the temperature of the glow plug was not lowered due to the cooling effect of No. 11, there were cases where the glow plug could not be maintained at a temperature necessary for smooth engine starting.

An object of the present invention is to provide a glow plug energization control device that prevents a drop in the temperature of the glow plug by providing a simple correction circuit that synchronizes the heating characteristics, and allows the engine to be started quickly and smoothly. It is in.

The glow plug energization control device of the present invention includes a rapid heating type glow plug, a relay 1 for supplying a large current to the glow plug, and a relay for supplying current to the glow plug via a current control resistor. 2, an energization control circuit for controlling the relays 1 and 2, and a key switch having an ON terminal for energizing the glow plug and a terminal 81 for energizing the starter motor and the glow plug. In the plug energization control device, the energization control circuit includes a capacitor C1 for determining a time constant.
and a timer T1 that controls the relay 1 and a comparator with an output feedback circuit that inputs the charging voltage of the capacitor C1, and a timer T1 that controls the relay 1, and a timer T1 that controls the voltage from the power supply side terminal of the glow plug and the ON terminal of the key switch to the capacitor +jC1. A charging circuit L1, a charging circuit L2 that connects the output terminal of the comparator 11q to the capacitor C1, and a charging circuit L2 that connects the capacitor C with a signal to the key switch ST☆;;:.
A reference voltage changing circuit that levels up the Iqt voltage of C1, and an inverted signal that avoids inverting the connection signal to the $- terminal and the output signal of the comparator are inputted via an AND circuit to discharge the capacitor C1. The charging circuit L2 charges the capacitor C1 only when the comparator is producing a high level output through an AND circuit, and the capacitor C1 is charged at a set voltage. (before timer 11 times up)
When the key switch S is connected to the ST terminal, the reference voltage is switched by the reference voltage changing circuit, and the timer T
1 is set to a longer time period, and a suitable hysteresis is provided to the timer T1, and after the capacitor C1 is charged to the set voltage, <timer T
1 after time-up), when the key switch S is connected to the ST terminal, it has the function of a pulse oscillator that oscillates at a predetermined time ratio, and when the engine is cranking, the key switch S is connected to the ST terminal. Injected fuel cold i1
The structure is to prevent the glow plug temperature from decreasing due to the action.

Next, the present invention will be explained based on one embodiment not shown in the drawings.

FIG. 1 shows a glow plug energization control device according to the present invention, where BAI- is a battery, G is a glow plug for rapid temperature rise attached to a sub-combustion seedling of the engine, and S is a battery BAT and a glow plug G. 92 digits between
F terminal, ON E terminal for energizing glow plug G, and ST for energizing glow plug G and starter motor.
A switch with a terminal, 1 is a relay for rapid temperature rise to supply a large current for the purpose of rapidly raising the glow plug (B), 2 is a relay for rapidly increasing the temperature after the glow plug G has risen to a predetermined temperature. Current limiting resistor 3 for the purpose of avoiding 1.5
1 is an energization control circuit that controls relay 1 and relay 2;

The energization control circuit 4 includes a capacitor C1 for determining a time constant.
and a comparator whose input is the charging voltage of the capacitor C1! Iiae, 11 depending on the voltage applied to the tallow plug G
11 type Kuima T1 with reference voltage system set to 1 constant,
The reference voltage of the timer T1 is changed by the connection signal to the ST terminal of the key switch S (energization signal to the starter motor), and after the timer T1 times out and during engine cranking operation, the timer]- 1 constitutes a pulse oscillator whose high level output time is determined according to the applied voltage of glow plug G, and relay 1 is turned on and off.
The correction circuit 5 is designed to perform + control, and the relay 2 is turned ON under predetermined conditions even after the engine starts, to stabilize combustion immediately after the engine starts, reduce exhaust smoke, and stabilize rotation. to perform the so-called afterglow.
'l-use timer T2.

The energization control circuit 4 of the claw 7' lug operates by means of the timer T1 and the correction circuit 5. For example, if the starter motor is operated during the high level output time limit of the timer T1, the output time limit of the timer T1 will be the first output time limit. time period [1st to 2nd]
is extended to the time limit t2. [After the 2-time limit has passed and when the time limit has not been extended, after the t1 limit has elapsed and while the starter motor is operating, the output time limit t4 of the Rolle Novel,
High level output time (repeat step 3). This allows the starter motor to be activated before the glow plaque has reached the required temperature for 4 minutes to start the engine. At the same time, after the glow plug has risen to the required temperature, relay 1 is controlled ON-OFF while the starter motor is operating at a3, and energization to the claw plug G is continued [tJi, t', former 11
Cooling of the glow plaque G by 6 = J Prevents the H1 temperature of the glow plaque G due to a drop in battery voltage due to the energization of the starter motor, and the T-bill starts the leap in the circle, (). The present invention will be briefly explained based on the circuit diagram shown in FIG. 2 and the operation ('1 time shift) shown in FIG.

412 In figure 43, 0[] sets timer T1 (:4 i
A comparator consisting of a comparator or a slope amplifier, the auxiliary constant of the ci+t timer 11 7) 4 constant,
This capacitor, ~11 is the charging voltage of capacitor C1, R1・-R1a resistance, 01~[)10ca tie-A
-t, constant [) 10 is constant voltage j dry tie A-t, C2 and C3i maconry, Ql is 1-run sister, 11J
3 and 12 are inverters, 13 and 14 are amplifiers,
]-3 is a control timer for the start indicator lamp, 15 is a complete explosion detection circuit, and T2 is a timer for controlling relay 2 for after-claw.

As shown in Figure 3 (a), when the key switch S is set from the OF terminal to the ON terminal, what is the relationship between the charging voltage v1 of the capacitor C1 at the input of the comparator OP and the reference voltage v2?
At first, capacitor C1 is in a discharged state (Fig. 3).
As shown in a), Vl < V2 and J5 comparator 01]
The output voltage VO is at a high level as shown in Figure 3 (2).After turning on the ON terminal of the key switch S,
Capacitor C1 receives voltage v3 from point A, which is the ON terminal and the power supply side terminal of glow plug G, via resistor R10.
A charging circuit has a resistor R1 and a tie-off D1 connected in series, and is connected through a resistor R7 and a diode D3 in series. The output voltage I:IV of the comparator ○P is connected to the charging circuit L2 connected to the
O is applied to start charging. The charging voltage V1 of the capacitor C1 is shown in FIG. 3(a) as follows: 1. −
The relationship between the reference voltage V2 determined by i, resistor R4, resistor R6, resistor R8, and diode D4 and the charging voltage V1 of capacitor C1, 11 hours until vl>V2, Comparator 01) outputs a high level,
A large current is supplied to the glow plug G through the inverter 11 and the inverter 12 by turning on the relay 1 as shown in FIG.
Rapid heating is performed.

Before the timer T1 time-up, that is, the capacitor °C
When the charging voltage V1 of 1 is lower than the reference voltage V2, the key switch S is turned on to the ST line terminal. The resistor R6 is disconnected, and the reference voltage v2 becomes V2 as shown in FIG.
1, the comparator OP outputs a high level for 12 hours until Vl > V21, and turns on relay 1.
A large current is supplied to the glow plug G to compensate for the drop in temperature of the glow plug due to the 11L (lower J'3.1: Hiso & I Aluminum 101) river of the battery electrician during cranking.

Resistors R12, R13, 1R14J3J: constitutes the discharge circuit 3 of the transistor Q1 (also the capacitor C1), and is used to switch the key switch S to the 8th terminal.
, resistor R13, and transistor Q through resistor R14.
1 Hose current is supplied to discharge the charge in capacitor C1. In this discharge circuit L3, while the output of the comparator ○P is at a high level, the output of the inverter 11 is at a low level, and the base current is grounded through the diode D6, so that the base current is supplied to transistors 1 to Q1. First, the transistor Q1 cuts off the discharge circuit L4.

As shown in Figure 3 (A), the charging voltage V1 of the capacitor C1
increases and when V1≧V21, the output of the comparator OP changes to a low level, and the charging current that was being supplied to the capacitor C1 via the charging circuit L2 having the resistor R7 and the diode D3 is no longer supplied, and the glow plug A voltage V3 is also generated via the charging circuit L1 based on the voltage j1 at the terminal Δ of the terminal G. The charge is floated.

When the output of comparator OP becomes low level, inverter 11
Then, the relay 1 is turned OFF via the inverter 12, so that the power supply to the glow plug G is stopped and the temperature of the glow plug G1 gradually decreases as shown in FIG.

Since the comparator ○ is an output return type comparator whose output is returned to the reference voltage input terminal via the resistor R8,
When the output of the comparator OP is inverted to low level, the voltage V21 for f'1 of the resistor R8 becomes the voltage V22 which is lower than the base voltage V21 as shown in Fig. 3 (a). , and the output of the inverter 11 becomes high level, so
The tie 7t -1' D G is reverse high) and the base current to the transistor Q1 is supplied through the resistor Q+4 i1j, which makes the transistor Q1 conductive and the resistor R3
The charge in the capacitor C1 is discharged at a set speed.

The charge of the capacitor C1 is discharged by the discharge circuit L3 consisting of the transistor Q1 and resistors R14 and R13, and the charge voltage V1 decreases, and after a set time V i <
It becomes V22. As a result, the comparator OP is again inverted to the high level, and the relay 1 is turned ON to supply a large current to the glow plug G, and the back reservoir 1 is discharged again until the glow plug G reaches a predetermined level of quality.

In this way, while the starter motor S is energized, the comparator O
The output of P is repeatedly inverted between high level and low level to maintain relay 1 ON-OFFL and claw plug G within a predetermined temperature range, thereby ensuring reliable and smooth engine starting.

Timer T3 is activated by key switch S as shown in Figure 3 (power).
Start by connecting the ST ON terminal to amplifier 1.
3, the glow lamp GL is turned on, and after the time-up, the glow lamp GL is turned off.

The complete explosion detection circuit 15 changes its output to high level by switching the key switch S from the ON terminal to the ST terminal 1[j and returning to the ON terminal, as shown in FIG.
The capacitor C1 is rapidly charged through the diode D7 as shown in Fig. 3 (A), the output of the comparator OP of 11 is changed to low level, the relay 1 is turned OFF, and the communication to the glow plug G is turned off.゛ Stop the city (?) and generate glow plug G by both engine combustion heat and Joule heat from electricity.
It prevents hyperthermia in the skin and protects against clog plaque G.

Timer T2 is a timer for afterglow control by relay 2, and as shown in Fig. 3 (g), S of key switch S is
After connecting the T terminal, set relay 2 for 5 hours, ○＼zaU,
Energize the claw 7 lug G through the current limiting resistor 2,
Stabilizes combustion immediately after engine startup for purposes such as rotational stability and JJI smoke reduction.

This afterglow is! 11 It operates under predetermined conditions controlled by the output of the cooling water crystal, claw plug voltage, vehicle speed sensor, etc., such as when the cooling water temperature is below a predetermined speed, the glow plug voltage is below a predetermined voltage, and the vehicle speed is below a predetermined speed. Sometimes done.

In addition, if the terminal voltage V3 of the glow plug G is not input due to poor contact of the coupler (coupler) or disconnection of the wire A7-harness, etc., it is connected to the comparator 01 via the resistor R10.
] Apply a high voltage to the input terminal of the relay 1 so that the energization period at the relay 1 does not become long.

This R10 is set as follows.

Resistance value of current limiting resistor 3 R<<RIO...(1) R1>>RIO, R2>>R10, R3>>RIO...
・(2) By doing this, when resistor 3 and resistor R10 are connected in parallel, glow plug terminal voltage V3 from equation (1)
is controlled by resistor 3 and is not affected by resistor RIO.

As described above, the glow plug energization control device of the present invention includes a rapid heating type glow plug, a relay 1 for supplying a large current to the glow plug, and a current control resistor for controlling the energization of the glow plug. Relay 2 for controlling the relay 1a5 and relay 2, an energization control 211 circuit that controls the relay 1a5 and the relay 2, an ON terminal for energizing the glow plug, and a starter motor 1'ag; key switch with child and 1li
At the energizing side dll '4a position of the glow plug obtained by i+, 11 (i energization control circuit (for determining the failure of moe = 1 = j, C1 and the terminal potential of the capacitor C1 as the input voltage 14 It consists of a quasi-electronic loaf and a comparator with an output feedback circuit, which controls the above-mentioned sushi-1.
Guru timer 1-1 is wart and the above Contin + JC1
is the photoelectric circuit L1 from nFj ○\ terminal and 11°j
Output 4 of the comparator: The charging circuit L2 from the child and the charging circuit 3 from the glow plug are combined, and the charging circuit L2 and the charging circuit L3 form an I-circuit.
) Charge the condenser C1 (n11) only when the comparator (q) is producing a high-level output, and use the ST signal connected to the ST terminal of the key switch as an input to set the standard of the capacitor C1. A reference voltage changing circuit for leveling up the voltage -4 and a discharge circuit L3 for discharging the capacitor C1 by inputting the output (Ei) from the comparator, which is an inversion of the output of the ST signal comparator, through an AND circuit. 1) When key switch S is connected to ST terminal before C1 is charged to the set reference voltage,
The inversion time of the output of the comparator is extended to extend the energization time to the claw plug via relay 1, and the key switch is turned off after the converter 1 is charged to the set voltage.
Since relay 1 is turned 0N-OFF according to the voltage at the glow plug terminal until it is returned to N terminal 2, comparator OP is 1.
, it is possible to control rapid heating of the tallow plug G via relay 1 and maintenance of the appropriate temperature range of the claw plug during cranking, and also change the reference voltage by cranking and change the time limit of the timer from tl to t21.
Even if the glow plug is cooled by lowering the battery voltage and injecting fuel, a predetermined temperature can be maintained, allowing the engine to start smoothly.

In addition, in the above embodiment, the movement of relay 1 due to cranking (correction of time is carried out in one beak), or the cool 7JI water temperature of the engine is detected and the condition 1!1 of the water temperature is added. Determine whether or not to make corrections between the operating parts of relay 1.
Additionally, such a correction circuit is more effective in raising the temperature of the claw plug more rapidly and eliminating the preheating wait time.

[Brief explanation of the drawing]

FIG. 1 shows the configuration of a glow plaque energization 11 control device according to the present invention. 1j is a circuit diagram showing an embodiment of the glow plaque energizing device according to the present invention, and FIG. In the diagram 1.2... Relay 3... vJi style III limit river resistor 4... Seven-way system Ml1 circuit to Tallow flag
]1, "2, T3...Timer ○P...Comparator C
1...Contensor Figure 3 S4 Showa procedural amendment February J, 1980 Commissioner of the Office of Special Corrections Tono 1, small I t1 indication 1982 patent application '4i152
376 No. 2, Name of the invention Gu C+- plug energization control device 3, ? Relationship with person Kushi 1'1 who does lli correction Special feature'
Japan Special 11sj Industry Co., Ltd. (451I) Representative Tanji Ogawa 11 Agent AG51f4 052-773-2449
13.? lli positive da 1 elephant Drawing 7, Supplement i] Contents of E Jokichi of the drawing (no change in content)

Claims (1)

[Scope of Claims] 1) A rapid heating type glow plug, a relay 1 for supplying a large current to the glow plug, and a relay 2 for supplying current to the claw plug l through a resistor for current control 211. and the energization control circuit that controls the relay 2 described in 111j, the ○ terminal for energizing the claw plug, and the ST for energizing the starter motor and glow plug l-. The energization control device for a glow plug is equipped with a key switch and a key switch, and the energization control circuit includes a capacitor C for determining a time constant.
1 and a comparator with a feedback circuit which inputs the charging voltage of the capacitor C1 and a terminal 1 which controls the relay 1, and a power supply side terminal (b) of the glow plug.
and the capacitor C from the ON terminal of the key switch.
1, a charging circuit L2 from the output terminal of the comparator to the capacitor C1, and a connection signal to the ST terminal of the key switch. A reference voltage change circuit, a connection signal to the ST terminal, and an inverted signal obtained by inverting the output signal of the comparator are inputted via an AND circuit.
) A discharging circuit L3 for discharging the container C1, and the charging circuit L1 and the charging circuit L2 connect the capacitor C1 via an AND circuit only when the comparator is producing a high level output. If the key switch is connected to the ST terminal before the capacitor C1 is charged to the set voltage, the reference voltage changing circuit changes the reference voltage to extend the inversion time of the output of the comparator, and relay 1 By extending the energization time to the glow plug, the capacitor C
After the capacitor C1 is charged to the set voltage, the capacitor C1 is connected to the discharging circuit L3 of the capacitor C1 and the charging circuits L1 and L2 from when the key switch S is connected to the 8th terminal until it is returned to the ON terminal. A glow plug energization control device characterized in that a relay 1 is turned ON-OFF according to a voltage at a glow plug terminal by repeated charging and discharging.