JPH0466738A - Control system of internal combustion engine - Google Patents

Abstract

PURPOSE:To shorten a connection line and facilitate a process of connection by arranging a flexible printed card (FPC) formed of a circuit which constitutes an electronic controller inside a throttle body, and connecting respective sensors and an actuator directly to the electronic controller. CONSTITUTION:A Ta sensor 7 and a MAP sensor 10 are attached to a throttle body 1 so that their probes are exposed upstream or downstream respectively from the throttle valve 2 of an air passage. Also an electronic controller 70 is attached to the throttle body 1. Furthermore, an electronic circuit is formed on the flexible printed card FPC so as to constitute the electronic controller 70. The FPC is directly connected to terminals of lead wires of a Th sensor 3 which detects the opening of a throttle valve 2, a Th sensor 3, an injector 4, a control valve 6, a Ta sensor 7, a Tw sensor 8, a fuel pump 9 and a MAP sensor 10. Consequently, the connection lines from respective sensors of an engine and an actuator, to the electronic controller are shortened so as to facilitate a process of connection.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an internal combustion engine control system, and in particular to an internal combustion engine control system comprising an internal combustion engine and its control device (electronic control device). The present invention relates to an internal combustion engine control system in which various installed sensors and actuators can be easily connected to an electronic control device.

(Prior Art) An electronic control unit installed in a vehicle having an internal combustion engine receives output signals from various sensors installed in the engine and engine peripheral equipment, and controls the upstream and downstream of the injector and throttle valve. It controls various actuators such as valves that control the opening of the communicating idle bypass passage, and sets the engine operating state to the optimum state.

This electronic control device is placed outside the engine room, for example, in a vehicle interior, and the electronic control device and the various sensors and actuators are connected using a wire harness.

Such an internal combustion engine control system was developed in the U.S. Pat.
No. 3672, No. 62-187294, etc.

(Problems to be Solved by the Invention) The above-described conventional technology had the following problems.

That is, as mentioned above, the conventional electronic control device was placed in a place other than the engine room, so the electronic control device and various sensors and actuators of the engine had to be connected using a wire harness. Assembling the internal combustion engine control system is troublesome.

In addition, when connecting the wire harness, the wire harness must be routed inside the vehicle, which makes connecting the harness even more troublesome.
Assembly man-hours increase.

Furthermore, the wire harness becomes longer, resulting in an increase in weight.

The present invention has been made to solve the above-mentioned problems, and its purpose is to shorten the connection line between an electronic control device and various sensors and actuators of the engine, and to facilitate the connection. An object of the present invention is to provide an internal combustion engine control system that can control the internal combustion engine.

(Means and operations for solving the problem) In order to solve the above problems, the present invention forms a circuit constituting the electronic control device on a flexible printed wiring board (hereinafter referred to as FPC), and The FPC is disposed within the throttle body, and is characterized in that the various sensors and actuators of the engine are directly connected to the electronic control unit.

Since the throttle body can be provided with various sensors and actuators for the engine, the distance between the electronic control device and the various sensors and actuators can be shortened.

(Example) The present invention will be described in detail below with reference to the drawings.

FIG. 2 is a schematic diagram showing the configuration of an embodiment of the present invention.

In the figure, the air taken in from the air cleaner 24 in the direction of arrow A is converted into a mixture by the fuel injected from the injector 4 disposed in the throttle body 1 having the throttle valve 2, and further flows through the intake manifold 22. , is introduced into the engine 21.

The fuel pump 9 sucks fuel (in the direction of arrow B) from a fuel tank (not shown) and supplies it to the injector 4 via the regulator 9R. The fuel not injected from the injector 4 returns to the fuel tank via the return pipe (in the direction of arrow R).

The air-fuel mixture is combusted within the engine 21, passes through the exhaust manifold 23 (in the direction of arrow C), and is further discharged via a muffler (not shown).

The bypass passage 5 is provided so as to communicate the air flow upstream side and the downstream side of the throttle valve 2.

This bypass passage 5 controls the amount of intake air during idling, and its opening degree is controlled by a control valve 6.

Inside the throttle body 1, a Ta sensor 7 for detecting atmospheric temperature and a MAP sensor 10 for detecting negative pressure in the intake pipe are arranged. The Ta sensor 7 and the MAP sensor 10 are attached to the throttle body 1 so that their probes are exposed on the upstream and downstream sides of the throttle valve 2 in the air passage within the throttle body 1.

Further, engine cooling water is introduced into a predetermined area within the throttle body 1, and a Tw sensor 8 for detecting the temperature of the engine cooling water is provided at the introduction portion.

The throttle body 1 further includes an electronic control device 70.
is installed. This electronic control device 70 is configured by forming an electronic circuit on an FPC as described later.

The FPC of this electronic control device 70 includes the throttle valve 2
It is directly connected to a Th sensor 3 that detects the opening degree of the injector 4, the control valve 6, the Ta sensor 7, the Tw sensor 8, the fuel pump 9, and the terminals and lead wires of the MAP sensor 10.

Reference numeral 11B is a lid, and the lid 11B has a connector IIA.
is installed. The electronic control device 70 is connected to this connector 11A.

Further, the connector 12A of the wire harness 12 is connected to the connector IIA, and thereby a spark plug, a battery, or various data input/output devices provided in the instrument panel are connected to the electronic control device 70. .

3 is a perspective view of the throttle body 1, FIG. 1 is a view of FIG. 3 viewed from the direction of arrow E, FIG. 5 is a cutaway sectional view of the main part of FIG. 1 is a sectional view taken along line FF in FIG. 1. FIG.

In FIG. 3, a frame IB that accommodates the electronic control device 70 is shown.
, and the lid 11Z that covers the frame IC is partially broken. In addition, in FIG. 1, the lid 11B and the lid 11Z are removed, and the frame IB and the frame IC are removed.
A part of it is broken. Furthermore, in FIG. 6, the TW sensor 8 is not broken. FIG. 4 shows a diagram with the electronic control device 70 of FIG. 1 removed.

In FIG. 1 and FIGS. 3 to 6, the same reference numerals as in FIG. 2 refer to the same or equivalent parts.

First, as shown in FIG. 5, the throttle body 1 consists of three bodies: a lower body IX, an intermediate member IY, and an upper body IZ. A throttle valve 2 is attached to the lower body IX, and an injector 4 is attached to the upper body IZ. This injector 4 is attached using a male screw 101 and a cap 102. In addition, in FIG. 5, the air passage in the throttle body 1 is depicted as being closed due to the arrangement of the injector 4, but in reality, in FIG. Air is allowed to pass through.

Fuel is introduced into the injector 4 via a fuel pump, regulator, and fuel passage 103 (not shown).

A Th sensor 3 is attached to the end of a shaft that supports the throttle valve 2 attached to the lower main body IX.

The lower main body IX and the upper main body IZ are connected by an intermediate member IY made of a material with relatively high heat insulation properties, such as resin.

The lower main body IX has an engine 21 (FIG. 2).
An air cleaner 24 (FIG. 2) is attached to the upper main body IZ.

Due to the negative pressure generated by the operation of the engine 21, outside air is drawn into the throttle body 1 through the window IW formed in the upper main body IZ (in the direction of arrow G).

Although not shown in FIG. 5, the throttle body 1 includes a bypass passage 5 as described above with respect to FIG.
is formed.

Next, in FIGS. 4 and 5, a lead wire 4A of the injector 4 is drawn out and a Ta sensor 7 is attached to the frame IB formed in the upper main body IZ.

Inside the frame IC, as shown in the figure, a MAP sensor 10,
A Th sensor 3 and a 7w sensor 8 are arranged. A male thread is formed on the outer circumference of the Tw sensor 8, and as shown in FIG. 6, it is attached to the throttle body 1 by screwing into a female thread formed on the lower main body IX. Reference numeral 104 in FIG. 6 indicates the lower body I
This is a region for introducing engine cooling water into the region 104, and the 7W sensor 8 is installed so that the probe of the 7W sensor 8 is exposed within this region 104.

The frame IC is further connected to a lead wire 9A of a fuel pump (fuel pump 9 shown in FIG. 2) and a lead of a control valve (control valve 6 shown in FIG. 2) via grommets 33 and 34. Line 6A is drawn.

Symbols 3B, 7B, 8B and IOB are Th sensor 3, Ta sensor 7.7w sensor 8 and MAP sensor 1, respectively.
0 terminal (pin).

Furthermore, a frame IE and a bin ID for fixing the FPC of the electronic control device 70 are formed within the frame IB of the upper main body IZ.

As shown in Figure 4, various sensors 3.7.8 and 1
0 and the lead wires 4A, 6A, and 9A are completed, as shown in FIG. through the electronic control device 70 into the frame I.
B and frame IC. In this case, if necessary,
FPC 70A constituting electronic control device 70 is bent.

A plan view of this electronic control device 70 is shown in FIG.

Note that in FIG. 7, illustrations of electronic circuits and conductive patterns arranged or formed on the FPC 70A are omitted.

As described above, the electronic control device 70 includes a predetermined electronic circuit provided on the FPC 70A.

As shown in FIG. 7, the FPC 70A has connection holes 55A to 55G for soldering the terminals and lead wires of the various sensors and actuators, and a terminal 11C (fifth terminal) of the connector 11A attached to the lid 11B. A connection hole 55Q for soldering the JC electronic control device 70 (FIG.) and a mounting hole 52 for fixing the JC electronic control device 70 to the upper main body IZ are provided.

After arranging the electronic control device 70 as described above, the terminals 3B, 7B, 8B, and 10B1 of the various sensors described above and the lead wires 4A, 6A, and 9A are soldered to each connection hole 55A to 55G of the FPC 70A. do.

After the above soldering is completed, insert the bottle ID (Fig. 4) formed in the frame IB into the mounting hole 52 drilled in the FPC 70A, and attach the bottle ID (see Fig. 8) to the tip of the bottle ID. The cap 62 is placed so that the FPC 70A is fixed in the frame IB. The cap 62 is fixed by the cap 6
Alternatively, the cap 62 may be placed on the bottle ID after applying an adhesive to the bottle ID.

Further, as shown in FIG. 9, a convex portion II is formed at the tip of the bottle ID, and a concave portion 62 is formed inside the cap 62A.
B may be formed, and the cap 62A may be fixed to the bottle 1D by fitting the convex portion 12 and the concave portion 62B.

In addition, in this embodiment, the FPC 70 by the cap 62
A may be fixed at only two places, or may be fixed as many times as necessary depending on the size of the electronic control device 70 and the like. Furthermore, if the electronic control device 7o is not too large, it is not necessary to fix the FPC 70A.

Next, the terminal 11C of the connector IIA attached to the lid 11B is soldered to the connection hole 55Q of the FPC 7OA. Then, attach the lid 1 to the punching frame IB using screws, for example.
Fix 1B.

Reference numeral 35 in FIG. 1 is a female screw for removing the lid 11B. Further, the lid 11B functions as a cover for the frame IB.

After that, the lid 11Z is attached to the opening of the frame IC using an appropriate method.

When the assembly of the throttle body 1 is completed in this way, the throttle body 1 is connected to the intake manifold 22 attached to the engine 21, and further,
An air cleaner 24 is attached to the throttle body 1. As a result, an engine system consisting of the engine and its control means (that is, the electronic control device 70) is completed. Therefore, it is possible to operate the engine system before mounting the engine on the vehicle body.

Now, as shown in Fig. 10, the terminals 3B, 7B, 8B, and 10B of various sensors and the FPC 70A are connected by soldering (reference numeral 40 in the figure). As shown, terminals 3B, 7B, 8
A connection may be made by forming or fixing a tab 42 on B and IOB, fitting a cap 41 to the tip of the terminal, and caulking if necessary.

Further, in the above-mentioned embodiment, the electronic control device 70 was described as being arranged in the frame IB, but among the circuits constituting the electronic control device 70, there are sensors (for example, MAP sensor) arranged in the frame IC. It goes without saying that the portion relating to the control circuit 10) may be formed on a separate substrate from the electronic control device 70 and placed within the frame IC. That is, the electronic control device may be formed on two or more substrates, and these may be arranged at different locations within the throttle body 1.

Furthermore, in the embodiment described above, the upper main body IZ to which the electronic control device 70 is attached is attached to the lower main body IX via the intermediate member IY having heat insulating properties. Such a configuration makes it difficult for engine heat to be conducted to the electronic control device 70 via the intake manifold 22.

However, such heat conduction to the electronic control device 70 can be prevented by forming the upper main body IZ or the lower main body IX itself from a material having heat insulating properties, or by forming the intake manifold 22 from a material having heat insulating properties. This can also be achieved by doing so.

Further, in this embodiment, the injector 4 is configured to inject fuel to the throttle valve 2, and the throttle valve 2 is thereby cooled by the latent heat of vaporization of the fuel. This increases the amount of heat radiated, and can further contribute to preventing heat conduction to the electronic control device 70.

Of course, instead of providing the injector 4, a carburetor may be used to inject fuel into the throttle valve 2.

Furthermore, when the engine has a plurality of cylinders, only one throttle body 1 may be provided, and the air-fuel mixture passing through the throttle body 1 may be distributed using an intake manifold having a branching structure. Alternatively, the throttle body 1 may be provided for each cylinder.

Furthermore, the shape of the FPC 70A constituting the electronic control device 70 is not limited to that shown in FIG. Of course, it is set to the shape.

Furthermore, it goes without saying that the present invention can be applied not only to internal combustion engine control systems for automobiles, but also to internal combustion engine control systems for vehicles such as motorcycles and work vehicles.

(Effects of the Invention) As is clear from the above description, according to the present invention, the connection lines between various sensors and actuators of the engine and the electronic control device are shortened, so there is no need to route a wire harness inside the vehicle. This makes it easy to assemble the internal combustion engine control system. Further, the weight of the internal combustion engine control system can be reduced. Furthermore, noise is less likely to be added to the output signal of the sensor.

Furthermore, since the sensors and actuators are directly connected to the FPC that constitutes the electronic control device, wiring errors are reduced and the connection between the electronic control device and the sensors and actuators is facilitated.

[Brief explanation of the drawing]

FIG. 1 is a view of FIG. 3 viewed from the direction of the arrow. FIG. 2 is a schematic diagram showing the configuration of an embodiment of the present invention. FIG. 3 is a perspective view of the throttle body. FIG. 4 is a diagram with the electronic control device of FIG. 1 removed. FIG. 5 is a sectional view of a main part of FIG. 3 viewed from the direction of arrow E. FIG. 6 is a cross-sectional view of FIG. 1 taken along line FF. FIG. 7 is a plan view of the electronic control device. FIGS. 8 and 9 are diagrams showing how the FPC is fixed by the cap. FIG. 10 and FIG. 11 are diagrams showing a method of connecting the terminals of the sensor and the FPC. 1...Throttle body, IB, IC...frame, IX
...lower body, IY...intermediate member, IZ...upper body, 2...throttle valve, 3...Th sensor, 3
B. 7B, 8B, IOB... terminal, 4... injector, 4A, 6A, 9A... lead wire, 6... control valve,
7... Ta sensor, 8... Tw sensor, 9... Fuel pump, 10... MAP sensor, 21... Engine, 22... Intake manifold, 52... Mounting hole, 55A~ 55G. 55Q...Connection hole, 62゜2A...Cat, 0...Electronic control unit, 70A...FPC

Claims (1)

[Claims] (1) The internal combustion engine is controlled by an internal combustion engine equipped with a throttle body that accommodates a throttle valve, a sensor and an actuator attached to the internal combustion engine, and an output signal of the sensor is taken in to control the actuator. In the internal combustion engine control system, the electronic control device has a circuit formed on a flexible printed wiring board and is disposed in the throttle body, and the electronic control device has a circuit formed on a flexible printed wiring board and is disposed in the throttle body, and the terminals and lead wires of the sensor and actuator are connected to each other. An internal combustion engine control system, wherein at least a portion of the throttle body is drawn into the throttle body and connected to the flexible printed wiring board.