JP4291958B2 - Engine valve arm case mounting structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an attachment structure for attaching an engine valve arm case to a cylinder head.
[0002]
[Prior art]
In a conventional engine, a valve arm chamber is configured by a valve arm case disposed above a cylinder head, and in the valve arm chamber, a valve arm, an upper end portion of an intake / exhaust valve, an upper end portion of a push rod, etc. Was stored. The valve arm case is fastened by a bolt member and attached to the cylinder head, and an elastic member such as a rubber member is interposed between the valve arm case and the cylinder head, And the vibration from the cylinder head is prevented from being transmitted to the valve arm case.
[0003]
[Problems to be solved by the invention]
As described above, the valve arm case is attached to the cylinder head by fastening with a bolt member via an elastic member, and even after the bolt member is tightened until the elastic member is compressed to the extent that it can be sealed, Since the bolt member can be further tightened, it is difficult to make the degree of tightening of the bolt member constant, and the degree of compression of the elastic member varies. Here, if the elastic member is held in an excessively compressed state, permanent deformation will occur over time, and the compressed state will not return to the state before compression, and the function as a sealing member The function as an anti-vibration member is lost. Therefore, when the bolt member is strongly tightened and the elastic member is excessively compressed, it is difficult to maintain a sufficient sealing effect and vibration isolating effect for a long time.
[0004]
[Means for Solving the Problems]
The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described.
[0005]
A valve arm shaft support member (7) is fixed on the upper surface of the cylinder head (1), and a valve arm shaft (11) that supports the valve arm is supported on the valve arm shaft support member (7). A valve arm chamber (5) covering the shaft support member (7) and the valve arm shaft (11) is configured by attaching a valve arm case (2) to the cylinder head (1), and the valve arm case (2 ) And the valve arm shaft support member (7) are attached via a fixing nut (32), and a fixing hole (2c) provided at the upper end of the valve arm case (2) and the fixing A rubber-like upper elastic member (56) is interposed in a compressed state between the flange (32a) of the nut (32), and the lower surface of the valve arm case (2) and the cylinder head (1 ) Between the upper elastic member (56) and the lower elastic member (55). The valve arm shaft support member (7) is formed with a screw hole into which the bolt member (31) into which the fixing nut (32) is screwed from above is screwed into the screw hole. The upper part of the screwed bolt member (31) protrudes above the valve arm shaft support member (7), and the valve arm chamber ( 5) Screwed into the fixing nut (32) inserted into the fixing member (32), and when the fixing nut (32) is screwed onto the bolt member (31) by a certain amount, the lower end is the valve arm shaft support member. Abutting on the upper surface of (7), the tightening position of the fixing nut (32) is restricted to a fixed position, and the lower half of the bolt member (31) is pivotally supported by the valve arm shaft support member (7); This leads to the valve arm shaft (11) and constitutes a detent of the valve arm shaft (11) .
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the present invention will be described.
[0007]
FIG. 1 is a plan view showing the mounting structure of the valve arm case of the present invention, and FIG. 2 is a front sectional view of the same.
[0008]
The structure of the valve arm chamber part comprised by the valve arm case of the engine of this invention is demonstrated. FIGS. 1 and 2 show a valve arm chamber portion in a two-valve engine in which one intake valve and one exhaust valve are provided for each cylinder. A valve arm case 2 is disposed on the upper surface of the cylinder head 1, and a valve arm chamber 5 is formed in the valve arm case 2. The fuel injection valve 17 provided for each cylinder is disposed outside the valve arm case 2 and is inserted into the cylinder head 1 from the upper surface of the cylinder head 1 that is not covered by the valve arm case 2. .
[0009]
The fuel injection valve 17 is pressed from above by the fuel injection valve presser 15 and its vertical arrangement position is restricted, so that the fuel injection valve 17 is fixedly attached to the cylinder head 1. The fuel injection valve retainer 15 is fixed to the cylinder head 1 by a bolt member 39. In the valve arm chamber 5, a valve arm shaft support member 7 is fixed to the cylinder head 1, and a valve arm shaft 11 that supports the valve arm is supported by the valve arm shaft support member 7. The lower part of the bolt member 31 is screwed onto the valve arm shaft support member 7 from above, and the valve arm shaft 11 is prevented from rotating by the lower half of the bolt member 31.
[0010]
The upper part of the bolt member 31 protrudes above the valve arm shaft support member 7, and a fixing hole 2 c is formed at a location corresponding to the position where the valve arm shaft support member 7 is disposed on the upper surface of the valve arm case 2. A fixing nut 32 as a fastening member is inserted into the fixing hole 2c from above the valve arm case. The fixing nut 32 is screwed onto the upper portion of the bolt member 31.
[0011]
Then, by tightening the fixing nut 32 to be screwed into the bolt member 31, the flange portion 32a of the fixing nut 32 locked to the peripheral edge portion of the fixing hole 2c presses the valve arm case 2 downward, Thereby, the valve arm case 2 is attached and fixed to the cylinder head 1. In this case, an upper elastic member 56 such as a rubber-like member is interposed between the flange portion 32a of the fixing nut 32 and the peripheral edge portion of the fixing hole 2c of the valve arm case 2 in a compressed state. While sealing between the fixing nut 32 and the valve arm case 2, vibration from the cylinder head 1 is prevented from being transmitted to the valve arm case 2.
[0012]
When the fixing nut 32 is screwed onto the upper portion of the bolt member 31 by a certain amount, the lower end abuts on the upper surface of the valve arm shaft support member 7 and cannot be tightened any further. That is, the fastening position of the fixing nut 32 is restricted to a fixed position by the valve arm support member 7. In a state where the fixing nut 32 is tightened until it comes into contact with the valve arm shaft support member 7, the upper elastic member 56 is in a compressed state, and the valve arm case 2 is attached and fixed to the cylinder head 1. That is, by tightening the fixing nut 32 until it comes into contact with the valve arm shaft support member 7, the upper elastic member 56 interposed between the fixing nut 32 and the valve arm case 2 is compressed to a certain degree of compression. The valve arm case 2 can be attached in a compressed state.
[0013]
Further, when the valve arm case 2 is attached to the cylinder head 1, a lower elastic member 55 such as a rubber-like member is interposed between the lower end of the valve arm case 2 and the cylinder head 1 in a compressed state. The valve arm chamber 5 is sealed, and vibration from the cylinder head 1 is prevented from being transmitted to the valve arm case 2. In other words, the valve arm case 2 attached to the cylinder head 1 has a so-called floating structure in which the upper elastic member 56 and the lower elastic member 55 are interposed in a portion in contact with the cylinder head 1.
[0014]
As described above, the lower elastic member 55 is interposed between the lower end of the valve arm case 2 and the cylinder head 1, and the upper elastic member 56 is interposed between the fixing nut 32 and the valve arm case 2. By fastening the fixing nut 32 to the bolt member 31 protruding from the valve arm shaft support member 7 fixed to the cylinder head 1, the valve arm case 2 is attached to the cylinder head 1. The inside of the valve arm case 2 is sealed, and vibration from the cylinder head is reliably prevented from being transmitted to the valve arm case. Further, the fastening position of the fixing nut 32 is restricted to a fixed position by the valve arm support member 7, so that the upper elastic member 56 interposed between the fixing nut 32 and the valve arm case 2 is tightened. The degree of compression of the elastic member can always be kept constant without passing too much.
[0015]
Further, as shown in FIG. 1, the lower elastic member 55 provided in a compressed state around the valve arm case 2 is installed in an area where the upper elastic member 56 is provided in a compressed state in the fixing nut 32 portion. Therefore, the surface pressure applied to the upper elastic member 56 is higher than the surface pressure applied to the lower elastic member 55. Accordingly, if the upper elastic member 56 and the lower elastic member 55 are configured to have the same hardness, the compression degree of the upper elastic member 56 is greater than the compression degree of the lower elastic member 55.
[0016]
Here, the upper elastic member 56 and the lower elastic member 55 do not exhibit the effect of sealing and vibration isolation when the degree of compression is smaller than a certain degree of compression, and if the degree of compression greater than the certain degree of compression continues, Is generated and the effect of sealing and vibration isolation is reduced. When the upper elastic member 56 and the lower elastic member 55 are in a certain degree of compression within a certain range, a high sealing effect and a vibration isolating effect are exhibited. Therefore, the degree of compression of the upper elastic member 56 and the degree of compression of the lower elastic member 55 must be configured to fall within a certain range when the valve arm case 2 is attached to the cylinder head 1.
[0017]
As described above, when the hardness is the same, the degree of compression of the upper elastic member 56 is greater than the degree of compression of the lower elastic member 55, so that the degree of compression in the state in which both the members are mounted falls within a certain range. Further, the hardness of the upper elastic member 56 and the lower elastic member 55 is changed according to the magnitude of the surface pressure applied to both. That is, for example, the hardness of the upper elastic member 56 that has a small installation area and a large surface pressure is set high, and the hardness of the lower elastic member 55 that has a large installation area and requires a small surface pressure is set low. As described above, the hardnesses of the upper elastic member 56 and the lower elastic member 55 are changed from each other so that the degree of compression of both falls within a certain range. Preferably, the degree of compression of both is substantially the same. It is better to set the hardness like this.
[0018]
By configuring in this way, the compression degree of the upper elastic member 56 and the lower elastic member 55 is kept within a certain range, or the compression degree of both is made uniform, so that the performance of each elastic member can be sufficiently exerted, and the seal It is possible to improve the durability and the durability of the elastic member, and to exhibit a high sealing effect and a vibration isolation effect.
[0019]
The upper elastic member 56 and the lower elastic member 55 exhibit their own sealing properties and vibration-proofing properties from a state where they are compressed to some extent to a state where they are compressed by approximately 20% due to a change in thickness in the compression direction. Since it is within a possible range, the degree of compression of the upper elastic member 56 and the lower elastic member 55 is set to be approximately 20% or less in the mounted state. As a result, the performance of the elastic members 55 and 56 can be sufficiently exerted, the sealing performance can be improved, the durability of the elastic member can be improved, and a high sealing effect and an anti-vibration effect are exhibited. It becomes possible.
[0020]
【The invention's effect】
Since the present invention is configured as described above, the following effects can be obtained.
A valve arm shaft support member (7) is fixed on the upper surface of the cylinder head (1), and a valve arm shaft (11) that supports the valve arm is supported on the valve arm shaft support member (7). A valve arm chamber (5) covering the shaft support member (7) and the valve arm shaft (11) is configured by attaching a valve arm case (2) to the cylinder head (1), and the valve arm case (2 ) And the valve arm shaft support member (7) are attached via a fixing nut (32), and a fixing hole (2c) provided at the upper end of the valve arm case (2) and the fixing A rubber-like upper elastic member (56) is interposed in a compressed state between the flange (32a) of the nut (32), and the lower surface of the valve arm case (2) and the cylinder head (1 ) Between the upper elastic member (56) and the lower elastic member (55). The valve arm shaft support member (7) is formed with a screw hole into which the bolt member (31) into which the fixing nut (32) is screwed from above is screwed into the screw hole. The upper part of the screwed bolt member (31) protrudes above the valve arm shaft support member (7), and the valve arm chamber ( 5) Screwed into the fixing nut (32) inserted into the fixing member (32), and when the fixing nut (32) is screwed onto the bolt member (31) by a certain amount, the lower end is the valve arm shaft support member. Abutting on the upper surface of (7), the tightening position of the fixing nut (32) is restricted to a fixed position, and the lower half of the bolt member (31) is pivotally supported by the valve arm shaft support member (7); reaches the Ben'udejiku (11) that, since constituting the detent of Ben'udejiku (11), with sealing the inside Ben'ude case, cylinder Vibration from head can be prevented reliably from being transferred to the Ben'ude case.
Moreover, the compression degree of an elastic member can always be kept constant, without tightening the interposed elastic member too much.
As a result, the performance of the elastic member can be sufficiently exerted, the sealing performance can be improved, the durability of the elastic member can be improved, and a high sealing effect and vibration isolation effect can be exhibited. Become.
[0021]
Further, the valve arm case is attached and fixed to the cylinder block via the upper elastic member and the lower elastic member, and the hardness of the upper elastic member and the lower elastic member is different from each other.
The degree of compression of the upper elastic member and the lower elastic member is kept within a certain range, or the degree of compression of both is made uniform, and the performance of each elastic member is fully exerted, improving the sealing performance and improving the durability of the elastic member. Therefore, a high sealing effect and an anti-vibration effect can be exhibited.
Further, in a state where the valve arm case is attached and fixed to the cylinder head, the performance of each elastic member can be sufficiently exhibited, the sealing performance can be improved, and the durability of the elastic member can be improved. A high sealing effect and a vibration proofing effect can be exhibited.
[0022]
The lower half of the bolt member (31) reaches the valve arm shaft (11) pivotally supported by the valve arm shaft support member (7) and constitutes a detent of the valve arm shaft (11). The detent of the valve arm shaft (11) can also be used by the bolt member (31).
[Brief description of the drawings]
FIG. 1 is a plan view showing a mounting structure of a valve arm case of the present invention.
FIG. 2 is a front sectional view of the same.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cylinder head 2 Valve arm case 5 Valve arm chamber 7 Valve arm shaft support member 31 Bolt member 32 Fixing nut 55 Lower elastic member 56 Upper elastic member

Claims (1)

A valve arm shaft support member (7) is fixed on the upper surface of the cylinder head (1), and a valve arm shaft (11) that supports the valve arm is supported on the valve arm shaft support member (7). A valve arm chamber (5) covering the shaft support member (7) and the valve arm shaft (11) is configured by attaching a valve arm case (2) to the cylinder head (1), and the valve arm case (2 ) And the valve arm shaft support member (7) are attached via a fixing nut (32), and a fixing hole (2c) provided at the upper end of the valve arm case (2) and the fixing A rubber-like upper elastic member (56) is interposed in a compressed state between the flange (32a) of the nut (32), and the lower surface of the valve arm case (2) and the cylinder head (1 ) Between the upper elastic member (56) and the lower elastic member (55). The valve arm shaft support member (7) is formed with a screw hole into which the bolt member (31) into which the fixing nut (32) is screwed from above is screwed into the screw hole. The upper part of the screwed bolt member (31) protrudes above the valve arm shaft support member (7), and the valve arm chamber ( 5) Screwed into the fixing nut (32) inserted into the fixing member (32), and when the fixing nut (32) is screwed onto the bolt member (31) by a certain amount, the lower end is the valve arm shaft support member. Abutting on the upper surface of (7), the tightening position of the fixing nut (32) is restricted to a fixed position, and the lower half of the bolt member (31) is pivotally supported by the valve arm shaft support member (7); A valve arm case mounting structure for an engine, which reaches the valve arm shaft (11) and constitutes a detent of the valve arm shaft (11) .

Images