JP2003020973A - Structure for installing pressure sensor on head gasket - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure for installing a pressure sensor 6 on a head gasket 1 allowing easy installation regardless of installation space and a pressure in a cylinder 4 to be detected. SOLUTION: The pressure sensor 6 is buried in the component member of the head gasket 1 near the inner peripheral surface 5 of the head gasket 1 for receiving a combustion pressure occurring in the cylinder 4. In detail, the pressure sensor 6 is disposed through a vent passage opening at a position facing the inner peripheral surface 5 of the head gasket 1 receiving the combustion pressure. Only by the conventional process in which the head gasket 1 is installed by providing it between a cylinder block 2 and a cylinder head 3, the installation of the pressure sensor 6 is completed regardless of the installation space, and the pressure in the cylinder 4 can be detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure sensor mounting structure for a head gasket having a built-in pressure sensor for detecting the pressure in a cylinder (combustion chamber) of an internal combustion engine and converting the pressure into an electric signal.

[0002]

2. Description of the Related Art Conventionally, as a device for detecting an in-cylinder (combustion) pressure of an internal combustion engine (hereinafter referred to as an engine), a dedicated mounting hole for mounting a pressure sensor on a cylinder head has been formed. A pressure sensor is attached to the part, or the pressure sensor is sandwiched between washers of the spark plug. The above-mentioned pressure sensor detects in-cylinder (combustion) pressure and is used for optimally controlling combustion conditions such as ignition timing, emission, output, and fuel consumption in the engine.

[0003]

However, the structure of the conventional pressure sensor has the following problems. For example, in a configuration in which a dedicated mounting hole for mounting the pressure sensor is mounted on the cylinder head and the pressure sensor is mounted at this portion, it is necessary to secure an installation space for mounting the pressure sensor on the cylinder head. However, in the vicinity of the cylinder head near the combustion chamber, there are intake passages, oil lubrication passages, etc., and it is difficult to secure an installation space for attaching the pressure sensor. Then, additional man-hours are required for mounting the pressure sensor.

In addition, for example, in a configuration in which a pressure sensor is sandwiched between washers of an ignition plug, when the ignition plug with a built-in pressure sensor is attached, the signal line drawn from the pressure sensor is attached without being entangled. It is necessary to attach the spark plug in consideration of the routing of these wirings, which is a problem because the number of man-hours is large.

In view of the above points, an object of the present invention is to provide a structure for mounting a pressure sensor on a head gasket, which does not require a space for installation and is easy to mount and can detect the pressure in the cylinder. It is in.

[0006]

In order to solve the above-mentioned problems, according to the structure for mounting a pressure sensor on a head gasket according to claim 1 of the present invention, the pressure sensor includes a cylinder block and a cylinder head in an internal combustion engine. It is characterized in that it is disposed in the vicinity of the inner peripheral surface of the head gasket which is interposed between the joint surfaces of and seals the both and is embedded in the head gasket. The inner peripheral surface of the head gasket is a surface that receives the combustion pressure generated in the cylinder.

As a result, the mounting of the pressure sensor is completed only by the same process as the conventional process in which the head gasket is interposed between the cylinder block and the cylinder head. Since the pressure sensor is arranged in the vicinity of the inner peripheral surface of the head gasket, which is the side that receives the combustion pressure generated in the cylinder, the pressure in the cylinder can be detected. In this way, it is possible to provide a pressure sensor mounting structure for a head gasket that can detect the in-cylinder pressure without making installation space a problem and facilitating mounting.

According to a second aspect of the present invention, the pressure sensor is arranged via a ventilation passage opening at a position facing the inner peripheral surface of the head gasket which receives the combustion pressure.

As a result, the pressure sensor can detect the combustion pressure generated in the cylinder by facing the inner peripheral surface of the head gasket without the pressure sensor directly touching the high temperature combustion gas.

According to the third aspect of the present invention, when the pressure sensor receives the expansion pressure in the cylinder at the time of combustion, the pressure applied to itself changes due to the pressure contact between the cylinder block and the cylinder head. However, the change in the applied pressure is detected.

That is, the pressure sensor together with the head gasket is located between the cylinder block and the cylinder head and is fixed by pressure contact by being tightened with bolts or the like. Then, when the expansion pressure in the cylinder at the time of combustion is received, the pressure applied between the cylinder block and the cylinder head changes. The pressure sensor detects the changing pressure force. By embedding it in the head gasket in this way, it becomes possible to detect the above-mentioned change in the pressing force, that is, the pressure in the cylinder.

According to the fourth aspect of the present invention, the external extraction portion for extracting the electric signal output from the pressure sensor to the outside is formed integrally with the head gasket, and
The head gasket is characterized in that it is formed so as to project to the outer peripheral end.

Thus, the electric signal output from the pressure sensor can be taken out to the outside without separately providing an external taking-out portion.

According to the fifth aspect of the present invention, the signal transmission line for relaying the electric signal by relaying between the pressure sensor and the external take-out portion is embedded and arranged in the gasket member constituting the head gasket. It is characterized by

As a result, the signal transmission line is embedded in the gasket member and integrated with the gasket member, so that the signal transmission line can be easily handled.

According to the sixth aspect of the present invention, the signal transmission line is patterned and mounted on a wiring sheet formed in a sheet shape, and the wiring sheet is embedded and arranged in a gasket member. It is characterized by

As a result, the signal transmission line is patterned and bundled (mounted and arranged) on the wiring sheet and then embedded in the gasket member, so that the arrangement of the signal transmission line is stabilized. Further, the wiring sheet formed in a sheet shape has an effect of making the thickness of the gasket member uniform when the wiring sheet is embedded in the gasket member.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A plurality of embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIGS. 1, 2 and 5 show a pressure sensor mounting structure for a head gasket according to a first embodiment of the present invention. FIG. 1 is a perspective view showing a pressure sensor attachment structure to a head gasket according to a first embodiment of the present invention. FIG. 2 is a partial arrow view of the pressure sensor built-in type head gasket in FIG. FIG. 5 is a partial cross-sectional view showing a 4-cylinder engine to which the head gasket with a built-in pressure sensor of the present invention is mounted.

As shown in FIG. 5, the head gasket 1 with a built-in pressure sensor is interposed between the cylinder block 2 and the cylinder head 3 in the engine 50, and is tightened with bolts or the like to be fixed by press-contacting them, so that both of them 2 3 is to be sealed. Originally, the head gasket has a function of holding the generated combustion pressure in the cylinder 4 and a function of forming passages such as a lubricating oil passage and a cooling water passage that communicate between the cylinder block 2 and the cylinder head 3 without leakage. Have The head gasket 1 with a built-in pressure sensor of the present invention has a function of detecting the in-cylinder (combustion) pressure in addition to the original function described above. In other words, as a device for detecting the in-cylinder (combustion) pressure, a plurality of pressure sensors for detecting the combustion pressure in the in-cylinder 4 are installed at positions corresponding to the respective cylinders of the head gasket so that the installation space does not matter. The present invention relates to a technique that facilitates mounting and can detect the in-cylinder pressure.

As shown in FIG. 1, a pressure sensor built-in head gasket (hereinafter, simply referred to as a head gasket) 1 is an inner peripheral surface of each cylinder which receives a combustion pressure generated in each cylinder 4. The pressure sensor 6 is embedded and disposed in the constituent member of the head gasket 1 in the vicinity of 5. Specifically, the pressure sensor 6 is arranged at a position facing the inner peripheral surface 5 of the head gasket 1 that receives the combustion pressure.
In the present embodiment, as shown in FIG. 2, an air passage 7 is formed between the pressure sensor 6 and the inner peripheral surface 5, and the pressure sensor 6 is provided inside the cylinder 4 via an air layer in the air passage 7. It was configured to come into contact with the hot combustion gas. That is, the one open end 7 a of the ventilation path 7 faces the inner peripheral surface 5. The presence of this ventilation path 7 prevents the pressure sensor 6 from directly contacting the high temperature combustion gas. The pressure sensor 6 is configured to detect the combustion pressure generated in the cylinder 4 via the ventilation passage 7. The constituent members of the head gasket 1 described above are
For example, it is composed of an inorganic filler and a synthetic rubber binder. Further, as the pressure sensor 6, for example, a piezoelectric element type or a strain gauge type is used.

The head gasket 1 is formed with an external extraction portion 8 so as to project to the outer peripheral end portion 9 of the head gasket 1. The external take-out portion 8 has a function of taking out an electric signal output from the pressure sensor 6 to the outside, and has a configuration in which a connector from an external ECU or the like (not shown) is inserted. The external extraction portion 8 is formed integrally with the head gasket 1 and contributes to a reduction in manufacturing cost of the head gasket 1.

A signal transmission line 1 for transmitting an electric signal by relaying between the pressure sensor 6 and the external take-out portion 8 described above.
Has 0. The signal transmission line 10 is embedded and arranged in a gasket member that constitutes a head gasket. As a result, the signal transmission line 10 is embedded in the gasket member and integrated with the gasket member, so that the signal transmission line 10 can be easily handled.

As described above, the mounting of the pressure sensor 6 is completed only by the same process as the conventional one in which the head gasket 1 is interposed between the cylinder block 2 and the cylinder head 3. Further, since the external take-out portion 8 projects to the outside of the engine 50, the signal of the pressure sensor 6 can be easily routed. In other words, the pressure sensor 6 for the head gasket 1 is capable of detecting the pressure in the cylinder 4 without making the installation space a problem and facilitating the mounting.
A mounting structure can be provided.

(Second Embodiment) FIGS. 3 and 4 show a pressure sensor mounting structure for a head gasket according to a second embodiment of the present invention. FIG. 3 is a perspective view showing a pressure sensor mounting structure for a head gasket according to a second embodiment of the present invention. FIG. 4 is a sectional view taken along the line BB in FIG. The same components as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted. The pressure sensor built-in head gasket 1A of the present embodiment is different from the first embodiment in that
The arrangements of the pressure sensor 6 and the signal transmission line 10 are different.

As shown in FIG. 4, the pressure sensor 6A in the head gasket 1A with a built-in pressure sensor receives the expansion pressure in the cylinder 4 during combustion, and the cylinder block 2
And the pressure applied to the cylinder head 3 due to the fact that it is pressed and fixed to the cylinder head 3 changes. And it is the structure which detects the change of this pressing force. Specifically, the pressure sensor 6A is
The wiring sheet 20 formed in a sheet shape is mounted and arranged. The signal transmission line 10A is also connected to the pressure sensor 6A and patterned and mounted on the wiring sheet 20.

The pressure sensor 6A mounted and arranged on the wiring sheet 20 does not have a portion (ventilation hole 7) for ventilating the cylinder 4 as shown in the first embodiment, and changes in combustion pressure in each cylinder 4 Is arranged in the wiring sheet 20 at a position close to the point where the wiring can be detected. That is, the pressure sensor 6A is a load (pressure) applied in the thickness direction of the thin plate-shaped pressure sensor 6A.
It is the structure which outputs the electric signal according to.

The wiring sheet 20 is made of an electrically insulating material and is embedded in a gasket member.
In this embodiment, the gasket 1 is provided on both sides of the wiring sheet 20.
The above-mentioned constituent members are attached to form a three-layer structure. In this way, the signal transmission line 10A is patterned and bundled (mounted and arranged) on the wiring sheet 20 and then embedded in the gasket member, so that the arrangement of the signal transmission line 10A is stabilized. Further, the wiring sheet 20 formed in a sheet shape has an effect of making the thickness of the gasket member uniform when the wiring sheet 20 is embedded in the gasket member.

In implementing the present invention, the structure of the pressure sensor 6 shown in the first embodiment and the structure of the wiring sheet 20 shown in the second embodiment may be combined. At this time, the pressure sensor 6A may be either mounted on the wiring sheet 20 or not mounted.

[Brief description of drawings]

FIG. 1 is a perspective view showing a pressure sensor mounting structure for a head gasket according to a first embodiment of the present invention.

FIG. 2 is a partial arrow view of the head gasket with a built-in pressure sensor in FIG. 1, viewed from the direction A.

FIG. 3 is a perspective view showing a pressure sensor attachment structure to a head gasket that is a second embodiment of the present invention.

FIG. 4 is a sectional view taken along line BB in FIG.

FIG. 5 is a partial cross-sectional view showing an internal combustion engine to which the head gasket with a built-in pressure sensor of the present invention is mounted.

[Explanation of symbols]

1 Head gasket with built-in pressure sensor 2 cylinder block 3 cylinder head 4 inside 5 Inner surface (of head gasket) 6,6A pressure sensor 7 air passage 8 External take-out section 9 Outer edge (of head gasket) 10, 10A signal transmission line 20 wiring sheet 50 Internal combustion engine

Claims (6)

[Claims] 1. A head gasket, which is interposed between a cylinder block and a cylinder head in an internal combustion engine to seal the two, and a pressure sensor that detects pressure and converts the pressure into an electric signal. A structure for mounting a pressure sensor on a head gasket, wherein the pressure sensor is attached to a position near an inner peripheral surface of the head gasket that receives combustion pressure generated in a cylinder and is embedded in the head gasket. 2. The head gasket according to claim 1, wherein the pressure sensor is provided via a ventilation passage that opens at a position facing the inner peripheral surface of the head gasket that receives combustion pressure. Pressure sensor mounting structure. 3. When the pressure sensor receives an expansion pressure in a cylinder at the time of combustion, the pressure applied to the cylinder changes due to being fixed in pressure contact with the cylinder block and the cylinder head. The structure for mounting a pressure sensor on a head gasket according to claim 1, wherein a change is detected. 4. An external extraction part for extracting an electric signal output from the pressure sensor to the outside, wherein the external extraction part is formed integrally with the head gasket and protrudes at an outer peripheral end portion of the head gasket. The pressure sensor mounting structure for a head gasket according to claim 3, wherein the pressure sensor mounting structure is formed by: 5. A signal transmission line for transmitting an electric signal by relaying between the pressure sensor and the external extraction portion, wherein the signal transmission line is embedded in a gasket member constituting the head gasket. The pressure sensor attachment structure to the head gasket according to claim 4, wherein 6. A wiring sheet formed in a sheet shape, wherein the signal transmission line is patterned and mounted on the wiring sheet, and is embedded in the gasket member. The pressure sensor attachment structure to the head gasket according to claim 5.