JP2001295736A - Injector mounting structure of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce noises caused by the vibration of a cylinder head cover or the like by receiving the impact force of an injector near the center of a cylinder head. SOLUTION: The cylinder head comprises a cylinder head body 1 and a camshaft housing 3 and is fastened in place by a cam cap bolt 5, together with a cam cap 4. The injector 7 is disposed vertically in both a cylindrical hole 11 in the cylinder head body 1 and a cylindrical hole 12 in the camshaft housing 3. An annular groove 13 is formed in the axial mid portion of the injector 7 and a cotter 14 divided into semicircular halves is inserted therein while passing through the cylindrical hole 12 formed in the camshaft housing 3. The camshaft housing 3 is thereafter assembled to the head body 1. The injector 7 is pressed and fixed to the cylinder head body 1 by the axial force of the cam cap bolt 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injector mounting structure for an internal combustion engine such as a direct injection type diesel engine and a direct injection type gasoline engine.

[0002]

2. Description of the Related Art A fuel injection system that injects pressurized fuel from an injector attached to a cylinder head into a cylinder is known as a direct injection type diesel engine or a direct injection type gasoline engine.

[0003] The injector mounting structure in a conventional direct injection type fuel injection system generally has a structure as disclosed in JP-A-11-82242 and JP-A-8-200179.

In this conventional injector mounting structure, the injector is generally fixed to the cylinder head by using a fork-shaped nozzle support. The nozzle support has one end engaged with the injector, the other fulcrum contacting and supported by the cylinder head, and a substantially central portion fastened to the cylinder head by a mounting bolt. The axial force of the mounting bolt is transmitted from the tip of the nozzle support to the injector, and biases the injector toward the cylinder head to fix the injector. The injector is generally arranged substantially on the center axis of the cylinder. In this case, the fulcrum of the nozzle support or the mounting bolt is arranged at a position distant from the center of the cylinder. As shown in Japanese Patent Application Laid-Open Publication No. H10-209, there is also a configuration in which the cylinder head is disposed on a side wall portion.

[0005]

In the injector of the fuel injection system, a component such as a needle valve moves inside,
The fuel injection and the stop are controlled by coming into contact with or separating from the seat portion, and therefore, in principle, an impact force due to a collision is generated. Particularly in common rail injection systems applied to diesel engines,
The injector generates a large impact force because, for example, internal components are driven by high-pressure fuel.

[0006] The impact force generated by the injector is transmitted from the portion where the injector is fixed to the cylinder head, and excites the vibration of the cylinder head and other engine parts to reduce noise and vibration during engine operation. Become one.

In particular, in a conventional injector mounting structure using a nozzle support, a fulcrum or a mounting bolt of the nozzle support is fixed to an end portion or a side wall of the cylinder head which has relatively low rigidity and easily vibrates. The vibration of the side wall excites the vibration of the cylinder head cover, and the noise and vibration tend to be particularly deteriorated.

[0008] Such a problem can be remedied by arranging the portion where the injector is connected to the cylinder head near the center of the cylinder head, which has relatively high rigidity and hardly excites vibration.

However, since other parts such as a valve lifter and a camshaft exist near the center of the cylinder head, it is difficult to arrange a nozzle support in addition to the injector. In particular, in a direct injection diesel engine, there is a problem that the valve included angle has a relatively large effect on the shape of the combustion chamber and hence the combustion performance, and the layout of parts near the center of the cylinder head becomes more difficult.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems. The injector is securely fixed to the cylinder head under the restriction of a limited space near the center of the cylinder head.・ To reduce noise generation.

[0011]

According to a first aspect of the present invention, there is provided an injector mounting structure for an internal combustion engine, wherein a camshaft housing for holding a camshaft is formed separately from a cylinder head body. Further, in the internal combustion engine fixed to the cylinder head main body by the fastening means, the injector is pressed by using the camshaft housing and fixed to the cylinder head main body.

That is, according to the present invention, the camshaft housing is formed separately from the cylinder head main body, and the camshaft is held by the camshaft housing. The injector is fixed. The camshaft housing may be continuous over all cylinders,
Alternatively, it may be divided into a plurality, for example, for each cylinder. The injector is pressed and fixed to the cylinder head body at the same time by fastening the camshaft housing to the cylinder head body without passing through a general fork-shaped nozzle support.

[0013] A second aspect of the present invention is a further embodiment of the present invention.
In the invention, a groove is formed along the circumferential direction on the outer peripheral surface of the injector, and a C-shaped clip is inserted into the groove, and the pressing force from the camshaft housing is applied to the injector via the C-shaped clip. It is characterized by being transmitted.

That is, when a C-shaped clip is inserted into the groove on the outer peripheral surface of the injector, the clip becomes a flange-shaped one, which engages with the camshaft housing and presses the injector toward the cylinder head body. Note that the above-described groove is only required to be in a range that can hold the C-shaped clip, and does not necessarily need to be formed on the entire circumference.

According to a third aspect of the present invention, a projection is formed on the outer peripheral surface of the injector, and the cross-sectional shape is formed in a hole for inserting the injector in the camshaft housing. A groove corresponding to the projection is formed along the axial direction of the hole.

The number of the protrusions may be one, but preferably a plurality of protrusions are provided. When a plurality of protrusions are provided, a plurality of the grooves are formed correspondingly.

According to the third aspect of the present invention, the injector is inserted into the hole of the camshaft housing with the projection aligned with the groove. After the insertion, the injector is rotated by a predetermined angle to shift the projection from the groove. As a result, it cannot be pulled out from the hole and is retained by the camshaft housing. By fastening the camshaft housing to the cylinder head main body in this state, the injector is pressed against and fixed to the cylinder head main body.

According to a fourth aspect of the present invention, which is a further reduced aspect of the third aspect of the invention, a concave portion is formed on the bottom surface side of the camshaft housing so as to be engageable with a projection on the outer peripheral surface of the injector. It is characterized in that the positioning of the injector in the rotation direction is performed by engagement with the projection. In this device, the injector is fixed in a state where the protrusion of the injector is engaged with the recess.

[0019] Claim 5 which is also dependent on claim 3
In the invention, a concave portion capable of accommodating the projection is formed on a joint surface of the cylinder head main body with the camshaft housing, and the rotational position of the injector is determined by fitting the concave portion with the projection. It is characterized by doing. In this case, since the projection of the injector is housed in the recess, the joint surface of the camshaft housing with the cylinder head body may be a simple plane.

Further, the invention according to claim 6 is characterized in that a gasket is interposed on a joint surface between the camshaft housing and the cylinder head body.

This gasket acts as a vibration absorbing material or a vibration damping material, preventing transmission of an impact force from the injector to the cylinder head main body via the camshaft housing, or the camshaft housing and the cylinder head main body, and the like. Vibration in peripheral parts is damped.

According to a seventh aspect of the present invention, which is a further reduced version of the sixth aspect, a projection is formed on a part of the bottom surface of the camshaft housing, and the projection is formed on the cylinder without the gasket. It is in direct contact with the head body.

That is, a gasket is interposed between the camshaft housing and the cylinder head main body at a portion other than the protrusion formed partially on the bottom surface of the camshaft housing. Since the shaft housing and the cylinder head main body come into direct contact with each other, the mounting accuracy of the camshaft housing to the cylinder head main body is increased.

The invention according to claim 8 is characterized in that, in any of the places where the pressing force is transmitted from the camshaft housing to the injector, a material that is more flexible than the material of the camshaft housing or the material of the outer cylinder of the injector, Alternatively, it is characterized in that a vibration damping material is interposed. Thereby, the impact force transmitted from the injector to the camshaft housing is suppressed, or the vibration generated by the injector is attenuated.

[0025]

According to the first aspect of the present invention, it is possible to fix the injector near the center of the cylinder of the cylinder head by using the camshaft housing having high rigidity, and the peripheral portion of the cylinder head having relatively low rigidity is provided. In particular, transmission of an impact force from the injector to the cylinder head side wall can be prevented, and vibration and noise during operation can be suppressed. Also, no nozzle support for fixing the injector is required, and the number of parts can be reduced as compared with the case where the nozzle support is used in a separate internal combustion engine of the camshaft housing, and the arrangement of parts around the injector becomes easy, And the weight can be reduced.

According to a more specific aspect of the present invention,
Because the clip is held by the injector by the spring action of the C-type clip itself, it does not accidentally disassemble when the injector is assembled to the camshaft housing, compared to using a left-right splitter such as a cotter. It is excellent in terms of assembly, disassembly and maintenance.

According to the third aspect of the present invention, the injector can be assembled to the camshaft housing and the cylinder head body without using a separate part such as a cotter, and the number of parts can be reduced. Also, after inserting the injector into the hole of the camshaft housing,
Since the injector is held by the camshaft housing only by rotating the injector by a predetermined angle about its central axis, the ease of assembly and the ease of disassembly are further improved.

In particular, according to the fourth or fifth aspect of the present invention, there is no need for a component for positioning the injector in the rotational direction, so that the assemblability is further improved and a reliable positioning performance can be obtained.

According to the sixth aspect of the present invention, generation of vibration and noise during operation can be suppressed by preventing transmission of an impact force or damping vibration by the gasket. In addition, the vibration transmission preventing function and the vibration damping function of the gasket can simultaneously suppress the valve operating system noise generated by the collision between the cam nose and the valve lifter.

According to the seventh aspect of the present invention, the projection formed on the bottom surface of the camshaft housing and the cylinder head main body come into direct contact with each other, so that the camshaft with respect to the cylinder head main body regardless of the presence of the gasket. The mounting accuracy of the housing is improved, and the positional accuracy of the center of the camshaft can be reliably ensured.

According to the eighth aspect of the present invention, it is possible to suppress the transmission of an impact force from the injector to the camshaft housing, or to attenuate the vibration generated by the injector, thereby reducing the vibration during operation.・ The generation of noise can be further suppressed.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a plan view of a cylinder head of a direct injection type diesel engine according to a first embodiment of the present invention. The illustrated example is for an in-line four-cylinder engine,
The cylinder head includes a cylinder head body 1 fixed to a top surface of a cylinder block (not shown) by a cylinder head bolt 2, and a side wall 1 of the cylinder head body 1.
a) The camshaft housing 3 is disposed on the inner peripheral side, and both are configured separately.

In the illustrated example, the camshaft housing 3 is integrally continuous over four cylinders, and two lifter bores 8 are formed for each cylinder for intake and exhaust. A bottomed cylindrical valve lifter (not shown) is held. A circular cam bearing hole is formed between the camshaft housing 3 and the cam cap 4, and the intake-side and exhaust-side camshafts 6 are held therein. As a result, the camshaft 6 is arranged above the valve lifter, and a cam (not shown) provided on the camshaft 6 constitutes a so-called direct-acting valve mechanism that directly operates the valve lifter. The camshaft housing 3 is
The cam cap 4 and the cam cap 4 are fixed to the cylinder head main body 1 together with the cam cap 4 in a so-called co-fastening manner by a cam cap bolt 5 penetrating the camshaft housing 3.

In the first embodiment, the valve lifter and the camshaft 6 can be provided integrally with the camshaft housing 3 as described above, so that the structure can be simplified.

FIG. 2 is a cross-sectional view of the cylinder head, and shows a cross section taken along line AA of FIG. As shown in the figure, the injectors 7 are arranged vertically along the cylinder center axis of each cylinder, and the cylinder head main body 1
And the camshaft housing 3
And a cylindrical hole 12 formed in the hole. An annular groove 13 is formed on the outer peripheral surface of the injector 7 at an intermediate portion in the axial direction of the injector 7, more specifically, at a position where the height substantially matches the height of the cylinder head top deck 16. A ring-shaped cotter 14 divided into two circular parts is inserted from the left and right.
FIG. 3 shows the annular groove 13 of the injector 7 and the cotter 1.
4 is shown in detail.

After the injector 7 is inserted into the cylindrical hole 12 formed in the camshaft housing 3, the cotter 14 is inserted from the left and right, and then the camshaft housing 3 is assembled to the head main body 1. As shown in FIG. 2, the camshaft housing 3 is pressed against the upper surface of the top deck 16 of the cylinder head body 1 by the axial force of the cam cap bolt 5, and at the same time, from the lower surface of the camshaft housing 3 to the cotter 14. A pressing force against the cylinder head main body 1 acts. Then, a pressing force is transmitted from the cotter 14 to the injector 7 via the annular groove 13, and the injector 7 is urged downward to the cylinder head body 1 in FIG. Here, between the lower surface of the large diameter portion of the injector 7 and the stepped portion 17 of the cylindrical hole 11, an annular packing 15 made of a material having a relatively low elastic coefficient is interposed, and gas in the cylinder is released. It is possible to prevent blow-through into the cylindrical hole 11 and at the same time, secure a margin for mounting the injector 7.

The cotter 14 is provided on the joint surface between the camshaft housing 3 and the cylinder head body 1.
The annular concave portion 18 for accommodating the cylindrical holes 11 and 12
It is formed on the outer periphery. The recess 18 is, as shown in FIG. 2, formed between the camshaft housing 3 and the cylinder head body 1.
The cotter 14 can be used for holding the assembled state of the cotter 14 by providing at least a part on the camshaft housing 3 side.

In the structure of this embodiment, the contact portion between the injector 7 and other parts is concentrated near the center axis of the cylinder head composed of the cylinder head body 1 and the camshaft housing 3. In the center of the cylinder head 1, that is, in the vicinity of the center of each cylinder, although the cavity of the water jacket 19 exists, the wall surrounding the cylindrical hole 11, the wall of the intake / exhaust port, and the like are formed in a complicated manner.
The rigidity is relatively high as compared with the portion near the side wall 1a.

In particular, in the first embodiment, since the present invention is applied to a direct acting type valve operating mechanism, a holding portion of a valve lifter is formed around the injector 7 in the camshaft housing 3. , Whereby the injector 7
, The width of the contact portion in the longitudinal direction is increased, and the portion where the injector 7 is assembled is made more rigid.

Therefore, as compared with the case where the injector impact force is transmitted to the side wall portion of the cylinder head via the fork-shaped nozzle support as described above, the impact force is transmitted to the center portion of the cylinder head as in the above embodiment. It is more difficult to excite the vibration mode of the cylinder head.
Therefore, coupled vibration with other components such as a cylinder head cover (not shown) attached to the cylinder head and an intake / exhaust manifold is not easily excited, and noise and noise during operation are reduced.
Deterioration of vibration can be suppressed.

In the conventional injector mounting structure using a nozzle support, a relatively high strength is required for the nozzle support and parts related thereto in order to withstand the pressing force for fixing the injector to the cylinder head, and the dimensions and Weight increases. On the other hand, in the structure of the present embodiment, the camshaft housing 3 designed to have high rigidity and strength from the beginning to hold the valve train components also serves as a component for mounting the injector. The manufacturing cost and the weight of the entire cylinder head can be reduced.

FIG. 4 is a perspective view of an injector 7 showing a second embodiment of the present invention. The basic structure of the cylinder head main body 1 and the camshaft housing 3 and the like is the same as that of the first embodiment described above. In this embodiment, the components for transmitting the pressing force from the camshaft housing 3 to the injector 7 are as follows. Instead of cotter 14, C
A mold clip 20 is used. This C-shaped clip 2
The width of the opening of 0 is set to be slightly smaller than the inner diameter of the annular groove 13 formed on the outer peripheral surface of the injector 7. The width of the opening is slightly widened by elasticity so that the opening can be inserted into the annular groove 13. Accordingly, after the clip 20 is inserted, the C-shaped clip 20 is not subjected to a predetermined tensile force.
Is retained in the annular groove 13 by its own elasticity, so that it is not accidentally disassembled.

In the second embodiment, the injector 7 is inserted into the camshaft housing 3 and the C-shaped clip 2
In a state where the assembling is performed with the 0 engaged, the assembly is not inadvertently disassembled, and the workability of assembling and the disassembly and maintenance are excellent.

Next, FIGS. 5 to 7 show a third embodiment of the present invention. The basic structure of the cylinder head body 1 and the camshaft housing 3 and the like is the same as that of the first embodiment described above, but in this third embodiment, the injector 7 does not have the annular groove 13, and Is formed on the outer peripheral surface. A pair of grooves 12 a having a sectional shape corresponding to the protrusions 7 a is formed on the inner peripheral surface of the injector insertion cylindrical hole 12 of the camshaft housing 3 along the axial direction of the cylindrical hole 12. That is, the cross-sectional shape of the cylindrical hole 12 including the groove 12a substantially matches the cross-sectional shape of the portion of the injector 7 having the protrusion 7a. On the joint surface of the camshaft housing 3 on the side of the cylinder head main body 1, a concave portion 31 having a depth capable of accommodating the projection 7 a is formed in an annular shape at the opening edge of the cylindrical hole 12. In particular, as shown in FIG. 7, the projecting portions 7a are provided at two positions on the bottom surface of the concave portion 31, specifically, at positions 90 degrees away from the groove portions 12a.
A relatively shallow positioning concave portion 31a is formed along the radial direction. Strictly speaking, the positioning recess 31a only needs to have a depth capable of accommodating the projection 7a.

FIG. 6 is an explanatory view showing a method of assembling the injector mounting structure according to the third embodiment. As shown in the drawing, in a posture in which the direction of the protrusion 7a of the injector 7 and the direction of the groove 12a of the camshaft housing 3 match,
The injector 7 is inserted into the cylindrical hole 12. After inserting the injector 7 to a predetermined position, the injector 7 is
A predetermined angle, for example, 90 degrees is rotated around the axis.
The projection 7a rotates within the recess 31, but at a position rotated by 90 degrees, it is in a state corresponding to the positioning recess 31a. When the camshaft housing 3 is fastened to the cylinder head body 1 in this state, the axial force of the cam cap bolt 5 acts as a downward pressing force in the figure, and simultaneously presses the camshaft housing 3 against the cylinder head body 1. A pressing force is transmitted to the injector 7 via a contact portion between the bottom surface of the concave portion 31 and the projection 7a, and the injector 7 is urged toward the cylinder head body 1 to be firmly fixed to the cylinder head body 1. become.

In the mounting structure of the third embodiment, the restraint and the transmission of force between the injector 7 and the camshaft housing 3 are realized by their own shapes without using new parts. The number of parts is reduced as compared with the case where auxiliary parts such as cotters are used.
If the injector 7 is rotated around the axis when the injector 7 is assembled to the camshaft housing 3, the injector 7 maintains the state of being naturally held by the camshaft housing 3. Workability at the time of assembly and disassembly is improved as compared with the case where parts are used.

As shown in FIG. 7, when the camshaft housing 3 exerts a pressing force on the injector 7, the positioning recess 31a on the bottom surface of the recess 31 of the camshaft housing 3 is inserted into the positioning recess 31a on the injector 7 side. The projections 7a are engaged, and positioning of the injector 7 in the rotation direction around the central axis is performed. Therefore, it is not necessary to provide another component for positioning in the rotation direction, and there is no possibility that the positioning is performed reliably and the rotation is performed carelessly.

FIG. 8 shows a fourth embodiment of the present invention. This fourth embodiment is a modification of the above-described third embodiment. A pair of protrusions 7a is provided on the outer peripheral surface of the injector 7 and a protrusion is formed in the cylindrical hole 12 of the camshaft housing 3. A pair of grooves 12a corresponding to the portion 7a is formed. Here, in the fourth embodiment, the concave portion 31 as in the third embodiment is not provided on the bottom surface of the camshaft housing 3 in which the lower end of the cylindrical hole 12 is open, and the bottom surface forms a simple flat surface. ing. A pair of positioning recesses 11a capable of accommodating the protrusions 7a are formed in the opening edge of the cylindrical hole 11 for inserting the injector of the cylinder head body 1 along the radial direction. The positioning recess 11a is formed in a direction different from the groove 12a by 90 degrees.

The assembling method of the fourth embodiment is the same as that of the first embodiment except that the injector 7 is inserted into the groove 12a of the camshaft housing 3 in such a manner that the projection 7a is aligned with the groove 12a.
It is the same as the third embodiment in that it is rotated by degrees. In the fourth embodiment, the projection 7a is projected from the bottom surface of the camshaft housing 3 because the recess 31 is not provided unlike the third embodiment.
Engages with the positioning recess 11a formed on the cylinder head body 1 side and is accommodated in the recess 11a.
Therefore, by the engagement between the positioning recess 11a and the projection 7a, the rotation of the injector 7 around the central axis is fixed, and positioning is performed. Therefore, a separate component for positioning the injector 7 in the rotational direction is unnecessary, and the injector 7 does not move inadvertently in the rotational direction.

FIG. 9 shows a fifth embodiment of the present invention. In this embodiment, the camshaft housing 3
A gasket 41 made of a sheet-like elastic member is interposed on a joint surface between the cylinder head body 1 and the cylinder head body 1. In addition,
The basic structure for fixing the injector 7 is shown by way of example with the same configuration as that of the first embodiment, but any of the fixing structures of the second to fourth embodiments is applicable.

The impact force generated by the injector 7 is transmitted mainly to the cylinder head main body 1 and the camshaft housing 3.
Can be prevented from propagating to other engine parts through the head body 1 by the gasket 41, and the vibration generated in the camshaft housing 3 is attenuated by the gasket 41. The vibration transmission preventing function and the vibration damping function of the gasket 41 are as follows.
It is also effective against valve train noise generated by a collision between a cam nose and a valve lifter.

In this embodiment, the bottom surface of the camshaft housing 3 is not a simple flat surface, and a slightly raised projection 3b is formed around the through hole into which the cam cap bolt 5 is inserted. Is formed. The gasket 41 is notched at the protrusion 3b. That is, the protrusion 3 b and the bottom surface 3 a that is in contact with the head main body 1 via the gasket 41 have a slight step substantially corresponding to the thickness of the gasket 41. There are a plurality of protrusions 3b in accordance with the number of cam cap bolts 5, but their bottom surfaces are co-processed with a milling machine or the like at the time of manufacture to form the same plane.

The camshaft housing 3 is fixed to the cylinder head main body 1 via the gasket 41 at the bottom surface 3a, and at the same time, the bottom surface of the projection 3b directly contacts the cylinder head main body 1 without passing through the gasket 41. I have. Since the cylinder head main body 1 and the processing surface of the projection 3b are in contact with each other, the positional accuracy of the camshaft housing 3 with respect to the cylinder head main body 1 is ensured, and the effect of preventing the transmission of the impact force and the vibration damping effect by the gasket 41 is obtained. In addition, it is possible to sufficiently secure the mounting position accuracy of valve train components such as a camshaft.

Next, FIG. 10 shows a sixth embodiment of the present invention. The basic structure of the cylinder head body 1 and the camshaft housing 3 and the like is the same as that of the first embodiment described above. In order to transmit a pressing force from the camshaft housing 3 to the injector 7, an annular groove 13 is formed on the outer peripheral surface of the injector 7. Is formed, and an annular cotter 14 divided into two semicircles is inserted into the annular groove 13. And
In the sixth embodiment, the camshaft housing 3
Between the cotter 14 and the cotter 14, a laminated washer 51 sandwiching the damping material is inserted.

In the sixth embodiment, the vibration generated by the impact force in the injector 7 is applied to the laminated washer 5.
Since 1 is damped, transmission of vibration to other parts of the engine via the camshaft housing 3 can be suppressed.

Further, in order to prevent the transmission of an impact force instead of the vibration damping effect, the conventional injector mounting structure using the nozzle support component requires the area of the contact portion between the nozzle support and the injector or the nozzle. Since the area of the contact portion between the support and the cylinder head was very small and limited, the surface pressure at the contact portion was increased, and as a result, it was difficult to interpose the vibration isolating material. Compared to the case where a nozzle support is used, a larger area of a portion transmitting the pressing force to the injector 7 can be secured, and the contact surface pressure is reduced. Therefore, a relatively flexible material such as copper is inserted as a washer. However, it is also possible to adopt a structure that reduces the transmission of the impact force.

[Brief description of the drawings]

FIG. 1 is a plan view of a cylinder head showing a first embodiment of an injector mounting structure according to the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG. 1;

FIG. 3 is an enlarged perspective view of an injector.

FIG. 4 is an enlarged perspective view of an injector showing a second embodiment.

FIG. 5 is an enlarged perspective view of an injector used in a third embodiment.

FIG. 6 is an explanatory view showing an assembling method of the mounting structure of the third embodiment.

FIG. 7 is an enlarged perspective view of the main part.

FIG. 8 is an explanatory view of an assembling method showing a fourth embodiment.

FIG. 9 is a sectional view showing a fifth embodiment.

FIG. 10 is a sectional view showing a sixth embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Cylinder head main body 3 ... Camshaft housing 3b ... Projection part 4 ... Cam cap 5 ... Cam cap bolt 7 ... Injector 7a ... Projection part 11 ... Cylindrical hole 12 ... Cylindrical hole 12a ... Groove part 13 ... Annular groove 14 ... Cotter 20 ... C-type clip 41 ... Gasket

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02M 61/16 F02M 61/16 F K XY

Claims (8)

[Claims] 1. A camshaft housing for holding a camshaft is formed separately from a cylinder head body,
In the internal combustion engine fixed to the cylinder head main body by fastening means, the injector is pressed and fixed to the cylinder head main body using the camshaft housing. 2. A groove is formed in the outer peripheral surface of the injector along the circumferential direction, and a C-shaped clip is inserted into the groove, and a pressing force from a camshaft housing is applied to the injector via the C-shaped clip. 2. The injector mounting structure for an internal combustion engine according to claim 1, wherein the fuel is transmitted to the injector. 3. A projection is formed on an outer peripheral surface of the injector, and a groove having a sectional shape corresponding to the projection is formed in a hole for inserting the injector in the camshaft housing along an axial direction of the hole. The injector mounting structure for an internal combustion engine according to claim 1, wherein: 4. A recess which is engageable with a protrusion on the outer peripheral surface of the injector is formed on the bottom surface side of the camshaft housing, and positioning of the injector in the rotational direction is performed by engagement of the recess with the protrusion. 4. An injector mounting structure for an internal combustion engine according to claim 3, wherein the mounting is performed. 5. A concave portion capable of accommodating the protrusion is formed on a joint surface of the cylinder head body with the camshaft housing, and the rotational position of the injector is determined by fitting the concave portion with the protrusion. The injector mounting structure for an internal combustion engine according to claim 3, wherein: 6. The injector mounting structure for an internal combustion engine according to claim 1, wherein a gasket is interposed at a joint surface between said camshaft housing and said cylinder head body. 7. The camshaft housing according to claim 1, wherein a projection is formed on a part of a bottom surface of the camshaft housing, and the projection directly contacts the cylinder head body without passing through the gasket. Item 7. An injector mounting structure for an internal combustion engine according to Item 6. 8. A part for transmitting a pressing force from the camshaft housing to the injector,
2. The injector mounting structure for an internal combustion engine according to claim 1, wherein a material softer than a material of the camshaft housing or a material of the injector outer cylinder or a vibration damping material is interposed.