JPS6075772A - Auxiliary starting apparatus for diesel-engine - Google Patents

Abstract

PURPOSE:To secure both of the superior temp. rise characteristic and after-glow function of a dual coil type glow plug by installing dual coil type glow plugs, voltage controller for controlling the voltage applied onto the glow plug, and a timer. CONSTITUTION:The dual coil type glow plugs 11, 13, 15, and 17 are connected in parallel and arranged into the respective combustion chambers of a Diesel engine, and the voltage applied into each glow plug is controlled by a voltage controller 19. Said voltage controller 19 is equipped with, for example, a dropping resistor 21, the first relay 23, etc. The first timer 27 for controlling the voltage controller 19 is provided to switch the transfer contact 25 of the relay 23. Therefore, each glow plug is applied with a voltage for improving the temp. rise characteristic from the voltage controller 19 by the control of the timer 27, and then applied with the drop voltage for improving the after-glow function through switching the transfer contact 25.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a starting assist device for a diesel engine using a dual coil type glow plug.

(Prior technology) Conventionally, seeded glow plugs, in which a heating element coil is placed inside a heat-resistant steel sheath and fixed with a filler, require a slightly longer preheating time than coil-type glow plugs, but are more durable and generate less heat. Because the resistor can be made thinner and each cylinder can be connected in parallel, the effect of disconnection is small, so it is widely used in starting aids for diesel engines11.
ing. A seeded type glow plug that enables rapid preheating is a dual-coil glow plug, in which multiple heating resistors are connected in parallel to form a heating element coil.

(Problems with the conventional technology) In recent years, glow plugs for starting diesel engines have been developed to improve the glow's temperature rise characteristics to shorten preheating time, improve blow-up properties for direct injection types, prevent white smoke during idling, and The indoor type is being developed with the aim of reducing noise immediately after startup and adding an afterglow function similar to fJ. However, dual-coil type glow plugs usually do not require a voltage or current controller because they have a self-temperature control function. With a dual-coil type glow plug, if you intentionally set the temperature rise characteristic to shorten the preheating time, the temperature will rise over the course of a day, so there is a risk of glow breakage due to overvoltage during afterglow, and afterglow. If the overvoltage at the moment of glow is set as the rating, problems arise in that the temperature increase characteristics deteriorate and the preheating time becomes longer.

(Purpose of the Invention) The present invention has been made with attention to such problems, and it is possible to achieve better temperature rise characteristics and afterglow function by controlling the applied voltage even in dual-coil type glow plugs. The aim is to achieve both.

(Summary of the Invention) The starting assist device for a diesel engine of the present invention is a dual coil type glow plug 11.13°15.17°.
And dual coil type glow plugs 11, 15,
A voltage controller 19 that controls the voltage applied to the terminals 15 and 17, and a timer 27 that controls the voltage controller 19 are provided.

(Example) The present invention will be described in detail below based on the accompanying drawings.

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

In the same figure, 11.13, 15.17, etc. are dual coil type glow plugs, which are connected in parallel and placed in each combustion chamber of a diesel engine, and become red hot when starting at a low temperature, causing the fuel to leak. It becomes the ignition starting point.

A voltage controller 19 controls the voltage applied to the dual-coil type glow plug 11 and the like, and includes, for example, a dropping resistor 21, a first relay, -2'5, and the like. The dropping resistor 21 is used to drop the voltage applied to the dual-coil type glow plug 11, etc., and is connected to a power source by switching the transfer contact 25 of the first relay 23.

27 is a first timer that controls the voltage controller 19;
The transfer contact 25 of the first relay 26 is switched according to the set time. That is, under the control of the first timer 27, the dual-coil type glow plug 11 first receives a voltage from the voltage controller 19 for the sole purpose of improving the temperature rise characteristic, and then switches the transfer contact 25. After that, it is subjected to a voltage drop whose sole purpose is to improve the afterglow function.

29 is a second relay, and 31 is its break contact. 5B is a second timer, which turns off the break contact 31 according to the set time and ends the glow energization.

35 is a power switch, 67 is a power supply, for example, 24
It is a V battery. 'The power switch 35 is a key switch (
It closes upon receiving an ON signal (not shown).

Next, the operation of the embodiment of the present invention will be explained.

Regarding a dual coil type glow lamp, FIG. 2 shows a timing chart of applied voltage, and FIG. 6 shows a timing chart of heating.

Before starting the engine, the transfer contact 25 of the g1 relay 23 is connected to the non-connected side of the dropping resistor 21. j) The second relay 29 is also closed.

Therefore, when the power switch 35 is closed by operating a key switch (not shown) (time t8 in Fig. 2 and Fig. 13), the glow temperature increase characteristic is activated, which enables rapid preheating to shorten the preheating time. The power supply voltage, which is intended only for improvement, is directly applied to the glow plug 11 of the odd coil type.

Next, continue preheating and start the engine' (t7 in Figure 2).
time) Then, the battery voltage, which once dropped when the engine started, rises with the start of charging, resulting in an overvoltage for glow energization.

Next, if the application of such an overvoltage is continued, the glow will be damaged, so after an appropriate time after the engine starts (at time t3 in FIG. 2 and the third step 11), the first timer 27 starts
The transfer contact 25 of the relay 23 is switched, and the power supply voltage is applied to the dual coil type glow plug 11 or the like via the dropping resistor 21. Therefore, f
The natural coil type glow plug 11 and the like enter afterglow without cutting off the glow due to the voltage drop of the dropping resistor 21.

Next, after a suitable time after the afterglow (14:00 in FIGS. 2 and 3), the second timer 63 starts the second relay 2.
9 to open the relay contact 61 and terminate the glow energization.

The set times of the first and second timers 27, 33, etc. are determined by either an on signal from a key switch, an on signal or an off signal from a starter (not shown), or the like.

It can also be determined by detecting overvoltage or rotational speed after starting the engine.

(Effects of the Invention) Since the present invention has the configuration described above, when starting the engine, there is no need to worry about overvoltage after starting the engine, and by applying a high applied voltage to improve the boosting characteristics of the glow, In addition to being able to start at a low temperature during the preheating period, by lowering the applied voltage during afterglow,
Good afterglow functions such as improved blow-up, reduced white smoke during idle, and reduced noise when cold are achieved.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the present invention. FIG. 2 is a timing chart of applied voltages for a dual coil type glow lamp. FIG. 3 is a timing chart of the temperature. 11.13, 15.17...Dual coil type glow plug 19...Voltage controller 21...Dropping register 23...1st relay 27 peaks 1st timer 29...2nd relay 33... 2nd timer 37... Power supply patent applicant Isuzo Jidosha Co., Ltd. Agent Patent attorney Sangai Tsuji (1 person) Figure 1 Figure 2

Claims (1)

[Claims] A diesel engine starting aid device that includes a dual coil type glow plug, a voltage controller that controls the voltage applied to the dual coil type blow plug, and a timer that controls the voltage controller.