JPS5825587A - Preheating auxiliary device for diesel engine - Google Patents

Abstract

PURPOSE:To make an effective afterglow possible, by providing a circuit to control a continuous rating apparatus for a preheating plug as well as an integrating timer to cut a continuous rating current for the preheating plug when an integrated value exceeds the fixed value after finding the integral of continuous rating time for the preheating plug by means of operation of the control circuit. CONSTITUTION:After engine starting, if preconditions for afterglow-the start of charging to a battery, engine temperature is below 60 deg.C and engine R. P. M. is below the fixed value-are fulfilled, with a combination of a gear position switch GSW and an accelerating pedal switch ASW, a glow plug 1 is energized only in time of a stop mode and thereby afterglow is achieved while continuous rating time for the glow plug 1 is found by an integrating timer 17. Should the continuous rating time exveed the setting time of the timer 17, it is killed till the integrated value of the rating time given by the timer 17 arrives at the fixed value so that the glow plug can be energized to heat when afterglow is required for smooth engine rotation; the afterglow is thus effectively achieved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a preheating auxiliary device for a diesel engine,
It is especially useful as a preheating auxiliary device after starting a diesel engine to prevent unpleasant clanking noises from the engine when it is cold and to prevent white smoke from incomplete combustion.

Diesel engines make an unpleasant clanking sound when the engine is not warmed up enough, and when driving in residential areas, it becomes noisy, and the white smoke caused by incomplete combustion is a cause of air pollution. This was one of the drawbacks of diesel fuel.

To prevent this clanging sound and white smoke when cold.

Even after the engine has started, electricity is applied to the glow plug for a certain period of time (3 to 4 minutes) to heat the inside of the engine.The so-called afterglow is completely performed.This afterglow after starting the engine is conventionally transferred from w4@ of the battery capacity etc. to the glow plug. The most commonly used method is to energize continuously for a predetermined period of time. However, this conventional continuous energization method requires unnecessary energization even while the vehicle is running, and also There is also a limit to the amount of electricity that can be passed from the m-kuma to the glow plug, and if the predetermined energization time is exceeded, the energization is automatically stopped, and continued preheating is required to ensure smooth engine rotation. However, it has the drawback that it cannot be energized even if it is heated, and that it is not suitable for effective use of energy for preheating.

Therefore, the present invention does not have the above-mentioned drawbacks of the conventional afterglow, can effectively energize the glow plug necessary for rounding to obtain smooth engine rotation, and can overcome the limited amount of energization. The present invention relates to a diesel engine preheating auxiliary device that can be used for.

Next, one embodiment of the present invention will be described in detail using one drawing and the like.

When a diesel engine is cold, the engine makes an unpleasant clanging sound and emits white smoke because the engine is not warmed up enough, and the water temperature is usually 60°C.
It has been empirically confirmed that this occurs when the temperature is below 6C. If the engine speed exceeds a certain value 14 to 15 seconds after the engine has been started, or if the vehicle's running speed exceeds a certain speed (part 8, 4), this unpleasant clanging noise will occur. It has also been empirically proven that the amount of air pollution will be reduced to a level that does not cause discomfort to people, and that white smoke will no longer be emitted.

Therefore, the conditions for performing afterglow are a problem, and generally it is necessary to perform it under the following first-order conditions.

(1) The sound of water is below 60@C (2) The vehicle speed is below a certain speed (!I) The vehicle is in a fitting state (when waiting at a signal after starting the vehicle, etc.). The figure is a circuit diagram used in a diesel engine preheating auxiliary device for performing afterglow that satisfies the above conditions. In FIG. 1, the EO is a power source, typically a vehicle battery. 1 is a glow plug, which is provided corresponding to the number of cylinders in a normal engine, and the figure shows four globe puffers 11M for a 4-cylinder engine/gin. 1b, 1
C81dft is shown. 2 is the key switch, turn it on
N, has a fixed contact at the start ST position. Reference numeral 5 denotes a rapid heating control device for the glow plug. At the same time as the key switch 2 is closed, the switch 4 is closed to heat the glow plug 1. When the preheating set temperature is reached, the switch 4C is turned on and off to control the glow plug. This is to maintain the temperature at the preheating set temperature. Qe is a temperature detection resistor of the glow plug 1, and the spinning control device detects and controls the temperature of the glow plug based on the voltage generated across the resistors B and e. R1 is a voltage drop resistor for regulating the current flowing through the globe 2 and the afterglow current is supplied from the power supply to the glow plug 1 through this resistor R1.

GSW is a gap position switch, and ASW is an accelerator pedal switch.As will be described later, a simulation circuit 15t representing running and stopping modes is formed by connecting the gap position switch GSW and the accelerator pedal switch ASW in series. , aftertag vx -f is performed. R3 is a resistor, Cs is a capacitor, and the resistor R and capacitor C form a delay circuit 16 of about 4 seconds. 15 is a comparator, R4 and R are resistors, and the reference voltage of the comparator 13 is determined by the resistors R4 and R. C1 is a precapacitor h, Rfl is a resistor, and the capacitor C1 and resistor R form an integration timer 17t for integrating one hour of afterglow as described later. The integration time of the integration timer 17 is determined by the resistance Rs and the capacitor 01.
It is determined based on the value of 1 minute due to the relationship with the battery capacity. 12 is a comparator %R11a R11
is a resistor that determines the reference voltage tube, and the output terminal of the converter 12 is connected to a diode D.

Dl is a diode, which is used to prevent the reverse flow of capacitor C1.@0m4 diode, which connects gap position switch GSW and accelerator pedal switch A.
When both SWs are closed, so-called every time the vehicle runs.
When the mode is on, current flows to the output terminal point of the controller 13, and when either one is open, that is, when in stop mode, the current flows from point a to point b of the integration timer 17. This is to prevent this from happening. R@s R11
R@e R@* R5. are resistors, respectively, for applying appropriate bias voltages to point a and transistor Trl+7r.

'frB is a transistor, afterglow relay s
@'i'r1, which is for driving tP, is also a transistor, and is for driving transistor Tlfk. Dl is a Zener diode to protect the transistor τ'at from surge voltage, ・ is a rotation detector that detects the engine rotation speed, ! is a comparator, and is set so that if the output of the rotation detector is below a certain value, the potential at the output terminal f is at a high level, and when it exceeds that value, it is inverted and becomes a low level. Reference numeral 20 is a timer, which generates an output for about 15 seconds after the engine is started, even if the number of engines exceeds a predetermined value, and performs afterglow even if the potential reaches the low level of the 6 points.

R1 * J- is a resistor that determines the reference voltage of comparator 9, 10 is an engine water temperature detector, 10 is a thermo switch, which opens when the water temperature is below 60"IC, and switches to 40"C.
It is set to close when it exceeds this value, but the value differs slightly depending on the model. Reference numeral 18 denotes a charging relay contact, which is a normally closed contact that operates and opens when the engine 5 is started and the output voltage of the generator reaches a charging potential. Diodes D, DB@D@-DlaD- form one AND circuit 1-9. This AND circuit becomes a gate circuit that determines whether the conditions for afterglow after the carrot start are met.

Next, the operation of the above circuit will be explained. First, when you turn the key switch 2 to the start sT position, current flows from the power supply go to the key switch 2 to the switch 4 to the resistance for temperature change detection fil, e to the fourth plug 1, and the rapid heating of the first part starts. do. When the glow plug 1 reaches the set temperature, the glow plug rapid heating control device S turns on and off the switch 4 to maintain the temperature of the glow plug 1 at the set temperature (approximately ?OO''C). At the same time, a starter relay (not shown) is activated and a starter (not shown) is activated.

When the engine starts, let go of key switch 2,
The key switch 2 is rotated back to the ON position. When the engine starts, the generator (not shown) also rotates, and when the output voltage reaches a charging potential, the charging relay is activated and its normally closed contact 18 is opened.

This prepares the system for starting the afterglow. When the engine water temperature is below 60@q, the thermoswitch 10 is opened and the diode D1.・No current flows through the terminal, resulting in a non-conducting state. Further, if the engine speed is below a predetermined value, the output signal of the rotation detector 8 causes the potential at the output end point f of the converter 9 to be maintained at a high level. As mentioned above, for 15 seconds after the engine is started, the potential at point e is maintained at a high level by the timer 20 even if the engine speed exceeds a predetermined value. When the potential at the six points is held at a high level, no current flows through the diode D-, making it non-conductive. This satisfies all the necessary conditions for the afterglow of ANDROW 19. Next, the gear position switch GSW and the accelerator pedal switch ASW are connected in a column 1! ! Continuation, Part 2
As shown in the figure, when the vehicle is running, the afterglow is performed only in the stop mode, when the vehicle is running, the afterglow is performed only in the stop mode, and/or when the gear body switch GSW and the accelerator pedal switch ASW are both released. When one side is opened,
An input is applied to the + side of the comparator 15 after the delay time of the delay circuit 16 (approximately 4 seconds) from the time of opening, and the output terminal point a is held at a high potential necessary to drive the transistor Tr&. . This is Citran Sister 7r1
．． Tr is conductive and s7r is conductive, so that the actuating coil 5b of the relay 5 is energized. When the relay 5 operates, its normally open contact 51 closes, and current flows from the power source Eo to the key switch 2 to the voltage drop resistor R1 to the relay contact 5a-+temperature detection resistor to the glow plug 1, starting afterglow. do. On the other hand, a charging current flows through the capacitor 01 from the power supply via the resistor Rh diode D1 while the potential at one point is high. In the driving mode, when both the gear shift switch GSW and the accelerator pedal switch ASW are closed, the comparator 15's +
ll is grounded.

(10) One point is held at a low level potential. When the potential at one point becomes low level, the transistor Tr 1 aTr
, is opened and the relay 5 is inoperative, its contact 51
9 is opened, electricity to glow plug 1 is cut off and afterglow is stopped. On the other hand, as the potential at point a decreases, the potential at point b also decreases, so charging to capacitor 〇 is stopped. Even if the potential at the point decreases, the diode D1
Because of this, the charge in the capacitor CI is never discharged. Then, in the same way as above, with the stop mode,
Transistors 7r1 and 7r become conductive, relay 5 operates, and afterglow occurs. In the running mode and stop mode as described above, the potential at the 0 point gradually becomes higher (due to the charge of the capacitor 01 due to the return of the negative terminal 9), and the potential at the one side input terminal of the comparator 12 becomes higher than the potential at the positive input terminal. When the voltage is high (the four output terminals of the comparator 12 have a low level potential, the transistor TT1* becomes non-conductive), the relay 5 becomes inoperable and tb, and the current to the glow plug is cut off. In this state, no afterglow occurs even if the mode represented by the combination of the accelerator pedal switch As!W and the gear positive (50 button switch) is stop. Timing chart explaining the above circuit operation) 11E3 In the figure, Tl indicates the delay time of the delay circuit 16.

However, the combination of the gear position open switch GSW and the accelerator pedal switch ASW is different from the cascade connection shown in Fig. ■ How to connect in parallel instead of cascade, ■
There is also a method of adding separate switches (for example, clutch switches) other than the two switches and connecting each switch in series or in parallel.

As explained in detail above, the preheating device for a diesel engine according to the present invention is suitable for use after the start of charging from the first generator to the battery after starting the second engine, when the engine water temperature is below 606C, and when the engine speed is below a certain value. When the conditions for glow are established, the combination of the gas cylinder switch and the accelerator pedal switch (1) represents the driving mode and stop mode of the vehicle, and the glow plug is energized only when in stop mode to perform afterglow. At the same time, the amount of time the glow plug is energized is integrated using an integration timer.

When the energization time exceeds the time set by the integration timer, the energization is cut off and afterglow is stopped, so the engine will not run smoothly until the energization time reaches the predetermined value. When preheating is required, it can be heated by electricity, and afterglow can be effectively performed to obtain smooth engine rotation.

This device exhibits an excellent effect that cannot be found in conventional diesel engine preheating auxiliary devices, in that it can more effectively utilize the amount of current that is limited by the battery capacity.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram used in a diesel engine preheating auxiliary device according to the present invention, Fig. 2 is a diagram showing the distinction between running and stopping, and Fig. 3 is a diagram showing tJ! FIG. 1 is a timing chart for explaining the circuit operation of FIG. 1. FIG. (la) 1...Glow plug, 2...Key switch, 5...
・Glow plug rapid heating control device, 4... Switch, 5.
...Afterglow relay%8...Rotation detector, 10
... Thermoswitch * Dl-DI' ... Diode bDl ... Zener diode, 15 ... Run, stop mode reef pseudo circuit, 16 ... Shut-up circuit, 17-...
・Integration timer, 18...Charging ring-〇 contact, 1?・
...AND circuit? , 11.12.13--Comparator, GSW--Gabodistomer switch, ASW
...Accelerator pedal switch, R1~R1r" resistance,
CI, Ctr capacitor, k...Temperature detection resistor Patent applicant ^Su-So Jidosha Co., Ltd. Attorney Patent attorney 2 people (14)

Claims (1)

[Claims] (1) A preheating plug, an energizing device that sends an electric current R to the preheating plug after the engine has started, a simulating circuit that represents the running and stopping modes of the vehicle, and a stop mode output signal of the wrinkle simulating circuit.
1. A control circuit that operates the energizing device and energizes the preheating plug; D-1, which is characterized by consisting of a cut-off integration timer! 'yv Engine preheating auxiliary device (
2) A preheating plug and a current t applied to the preheating plug after the engine starts.
an energizing device m, a simulated ijR circuit representative of running and stop modes of both cars, and a control circuit that activates the overcurrent device f and energizes the preheating plug according to the stop mode O output signal of the simulated circuit; an integration timer that integrates the energization time to the preheating plug due to the operation of the control circuit and outputs an output and cuts off the energization to the preheating plug when the cumulative amount exceeds a certain value; and conditions for energizing the preheating plug after the engine starts. 1. A preheating auxiliary device for a diesel engine, comprising a gate circuit that controls the energizing device by determining whether or not the energization device is ready.