JPS585451A - Control device of engine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an engine control device, and particularly to one in which various control devices are controlled in accordance with engine temperature.

Generally, various control devices such as an engine air-fuel ratio control device, ignition timing control device, exhaust recirculation control device, etc. are controlled according to the engine temperature in order to perform optimal control according to the engine operating state. (Unexamined Japanese Patent Publication No. 54-470
(See Publication No. 14).

In addition, recently, by connecting the Vorta pump for circulating cooling water inside the engine with its own motor or with the engine via a variable pulley or clutch, the speed ratio relative to the engine rotation can be made variable. A water pump drive control device that independently controls the drive to reduce drive loss and improve fuel efficiency, as well as precisely control the engine temperature.
138630, U.S. Pat. No. 51-138631) have been proposed.

By the way, when controlling such various control devices according to the engine temperature, detecting the temperature of the engine wall near the combustion chamber of the engine is a direct and accurate way to detect the engine temperature. Directly affected by temperature, engine thermal cycle fluctuations, i.e. intake, compression,
There is a problem in that surging phenomena occur in various control devices due to various thermal fluctuations during the explosion and exhaust strokes.

Therefore, in view of the above, the present invention provides a temperature sensor whose temperature-sensing section contacts the engine wall surface near the combustion chamber and detects the engine wall surface temperature when controlling various control devices according to the engine temperature as described above. is provided, and the output of the temperature sensor (
Engine wall temperature signal) within a predetermined period (within cycle)
By detecting the average value of , and controlling various control devices based on this average value, temperature detection is performed by averaging engine thermal cycle fluctuations within a certain period of time, thereby controlling various control devices. It is an object of the present invention to provide an engine control device that can perform engine control with high precision without causing a surging phenomenon.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

FIG. 1 shows an example in which various control devices of the present invention are applied to a water pump drive control device, where 1 is an engine, 2 is a water pump for circulating cooling water inside the engine 1,
Reference numeral 3 denotes a radiator, and the engine l and the radiator 3 are connected by a first circulation path 4a and a first circulation return path 4b to form a first circulation path 4. The bypass passage 5 branches off from the middle of the first circulation passage 4a to bypass the radiator 3.
are arranged in parallel, and a thermostat 6 is disposed at the branching point of the bypass passage 5 with the first circulation passage 4a.When the cooling water temperature is lower than the set value and the engine is cold, the thermostat 6 is closed. By closing the first circulation path 4a and opening the bypass passage 5, the cooling water is bypassed without being circulated to the radiator 3, promoting warming up of the engine 1, while completing engine warming up when the cooling water temperature is higher than the set value. Thereafter, by opening the thermostat 6, the bypass passage 5 is closed and the first circulation passage 4a is opened, whereby the cooling water is circulated to the radiator 3 and the normal engine 1 is efficiently cooled. Further, 7 is a second circulation passage for circulating the cooling water of the engine 1 to the heater core 8,
The downstream end of the second circulation passage 7 is connected to the middle of the bypass passage 5, and is connected to the bypass passage 5 and the first circulation return passage 4b.
A part of the second circulation passage 7 also serves as part of the second circulation passage 7.

A switching valve 9 is interposed in the middle of the second circulation passage 7, and when the switching valve 9 is opened, the cooling water is circulated to the heater core 8, and the heater core 8 blows air from a blower (not shown). is configured to generate warm air.

Reference numeral 10 denotes a drive device comprising a motor 12 that independently drives and controls the water pump 2 via a belt transmission mechanism 11 so that the speed ratio is variable with respect to the rotation of the engine 1; A control circuit 13 for controlling the motor 12 is connected to the motor 12 of the device 10 .

Further, 14 is a temperature sensor for detecting the engine wall surface temperature, and as shown in FIGS. 2 and 3, the temperature sensor 14 has grooves 15a and 15b extending in the shape of wings on both sides in the engine wall 1a. A cylindrical sensor insertion hole 15 is formed, and the bottom surface of the insertion hole 15 is connected to the combustion chamber l of the engine 1.
One groove portion 15 of the charging hole 15 faces the side b.
A faces the cooling water passage 16 at a substantially intermediate position between the combustion chamber 1b and the cooling water passage 16 formed in the engine wall 1a. In the charging hole 15, one of the grooves 15 is provided.
A cylindrical temperature sensing portion 1 having a protrusion 17a that is fitted into the a.
7 is fitted, and is pressed and fixed by a spring 19 interposed between the temperature sensing portion 17 and a plug 18 screwed into the sensor insertion hole 15, and the protrusion of the temperature sensing portion 17 1
7a is pressed against the bottom surface of one groove 15a of the sensor insertion hole 15 with a constant pressure by a spring 2° inserted into the other groove 15b. Further, the terminal 21 of the temperature sensing section 17 is led out to the outside through a lead-out hole 22 formed in the plug body 18 and connected to the control circuit 13. 17 and inputs the detection signal to the control circuit 13.

The control circuit 13 includes, as shown in FIG. 4, a temperature detection circuit 23 that outputs a voltage signal corresponding to the engine wall surface temperature in accordance with the detection signal (resistance value signal) of the temperature sensor 14;
An oscillation circuit 24 that outputs a sampling period signal with a predetermined period (for example, a period corresponding to 2 rotations in the case of a 4-cycle engine) that is variable depending on the engine rotation speed, and an oscillation circuit 24 that receives outputs from the temperature detection circuit 23 and the oscillation circuit 24. , an averaging circuit 25 that outputs an average value signal obtained by averaging the output signals from the temperature detection circuit 23 within the sampling period.
a sampling circuit 26 that samples the average value signal of the averaging circuit 25 in synchronization with the sampling period signal of the oscillation circuit 24; and a sampling circuit 26 that controls the output current to the motor 12 in accordance with the output signal of the sampling circuit 26. The excitation coil 12a of the motor 12, which is equipped with an output current control circuit 27 and an amplification circuit 28 that amplifies the output current signal of the output current control circuit 27, is supplied with power from the power source B according to the output current signal. The field current to the motor 12 is controlled via the transistor Tr, and the output current signal turns on the relay MR to energize the armature 12b of the motor 12 from the power source B.
The driving of the driving device 10 is imposed according to the average value of the engine wall surface temperature within a predetermined sampling period. (In Fig. 4, S is a key switch.

Next, the operation of the above embodiment will be described. The temperature sensor 14 detects the wall surface temperature of the engine 1, and this detection signal is input to the control circuit 13. Then, the control circuit 13 is instructed to convert the detection signal from the temperature sensor 14 into a voltage signal corresponding to the engine wall surface temperature by the temperature detection circuit 23, and then by the averaging circuit 25 within a predetermined sampling period. An average value is calculated, and the sampling circuit 26 samples this average value signal. Subsequently, in response to the output signal from the sampling circuit 26, the output current control circuit 27 outputs an output current signal corresponding to the output current to the motor 12, which is preset based on the engine wall surface temperature, and the output current signal is output from the amplifier circuit 28. After being amplified, the signal is input to the motor 12. As a result, the field current of the motor 12 is controlled according to the output current signal, and the rotation speed of the motor 12, that is, the rotation speed of the water pump 2, is controlled according to the average value of the engine wall surface temperature within a predetermined sampling period. , temperature control of the engine 1 is performed.

In that case, since the drive control of the water pump 2 is performed based on the direct engine wall temperature and the average value of the engine wall temperature within a predetermined period, the wall temperature is detected unaffected by the thermal cycle fluctuations of the engine 1. For,
No surging phenomenon occurs in the water pump 2, and the temperature of the engine 1 can be controlled to an appropriate temperature with good responsiveness and accuracy. In particular, in this embodiment, the temperature sensor 1
The temperature sensing section 17 of No. 4 detects approximately the average value temperature of the wall surface temperature on the combustion chamber 1b side and the wall surface temperature on the cooling water passage 16 side at its side surface (protrusion 17a), so that the temperature sensing section 17 of No. The temperature of the engine 1 can be detected more accurately without being affected, and the temperature control of the engine 1 can be more accurately controlled.

Note that the present invention is not limited to the above-mentioned embodiment, and includes various other modifications. For example, in the above-mentioned embodiment, the water pump 2 has a speed ratio relative to the rotation of the engine 1. As a drive device 10 that performs variable drive control, a motor 12 that is driven independently of the engine 1 is provided,
Although the motor 12 drives and controls the water pump 2 via the belt transmission mechanism 11, it is also possible to drive and control the water pump 2 by connecting the engine 1 and the water pump 2 via a variable pulley or a clutch. Of course, the motor as in the above embodiment is preferable in terms of ease of control.

In addition, although the above embodiment describes the case of controlling a water pump drive control device, the present invention also applies to control of various control devices such as an air-fuel ratio control device, an ignition timing control device, and an exhaust gas recirculation control device. Needless to say, it can be applied in the same way.

As explained above, according to the present invention, in controlling various engine control devices according to the engine temperature, the control is performed based on the average value of the engine wall surface temperature within a predetermined period. It is possible to accurately control various control devices without causing a surging phenomenon.

[Brief explanation of drawings]

The drawings illustrate the implementation of the present invention: Fig. 1 is a diagram showing the engine cooling water circulation system, Fig. 2 is a cross-sectional view showing the installed state of the temperature sensor, and Fig. 3 is Fig. 2. FIG. 4 is a block diagram of the control circuit. DESCRIPTION OF SYMBOLS 1... Engine, 1b... Combustion chamber, 2... Water pump, 10... Drive device, 12... Motor, 1
3... Control circuit, 14... Temperature sensor, 23...
Temperature detection circuit, 24...Oscillation circuit, 25...Averaging circuit, 26...Sampling circuit, 27...Output current control circuit procedural amendment (voluntary) August 27, 1980 1, Incident Indication of 1982 Patent Application No. 102612 2 Name of the invention Engine control device 3 Relationship to the case of the person making the amendment Patent applicant address 3-1 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Name (5)
15) Toyo Kogyo Co., Ltd., Yoshiki Yamazaki 4, Agent Address: 550 Den 06 (445)l
J87, Contents of amendment・As per attached sheet 8, 0 sickles of attached documents

Claims (1)

[Claims] (1) A temperature sensor whose temperature sensing part contacts the engine wall near the combustion chamber and detects the engine wall temperature, and which receives the output of the temperature sensor and uses various An engine control device comprising: a control circuit that controls the control device.