JPH0133814Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a timing belt cover mounting structure, and in particular prevents engine vibrations from being transmitted to the timing belt cover through the bolts at the tightening part. It is something to do.

[Conventional technology]

Engine timing belt cover is water,
In order to prevent the timing belt from deteriorating or skipping due to the intrusion of foreign substances such as oil and dirt, a sealing gasket is installed between the timing belt and the end face of the engine, as shown in Japanese Utility Model Application Publication No. 158109/1983, for example. many. Conventionally, as shown in FIG. 4, the timing belt cover is bolted to the end face c of the engine with a washer b made of an elastic material interposed therebetween.

[The problem that the idea aims to solve]

However, in the case of the structure described above, the head of the bolt directly presses the cover a, and the tightening force acts directly on the cover a, so the vibration of the engine body is transmitted to the cover a through the bolt. be done. In addition, the cover a is usually a lightweight molded product made of synthetic resin, thin metal sheet, etc., and has a relatively large flat area on the front surface, so vibrations from the engine cause membrane vibration in the cover a, causing noise. It is the source of this.

In this invention, an elastic material is attached to the bolt insertion hole of the cover, and the tightening force of the bolt is not applied directly to the cover, and the bolt is clamped only at the non-pressing part of the elastic material cover, thereby reducing noise. This provides a mounting structure for a cover that can be measured.

[Issues to solve the problem]

In order to achieve the above object, the timing belt cover mounting structure of the present invention has a container shape and has an edge portion bolted to the end face of the engine to cover the timing belt attached to the end face of the engine. A protrusion is formed on the end face to surround a screw hole into which a timing belt cover mounting bolt is screwed and to form a gap between the timing belt cover and the timing belt cover. A sealing material for sealing the gap is disposed, and the timing belt cover has a cylindrical shape with a hole through which the threaded portion of the bolt is inserted, and has an outer diameter larger than the head of the bolt. A bolt insertion hole is provided into which the outer diameter of the elastic material, which has a larger diameter than the outer diameter of the projection, is inserted and fixed.

[Effect]

When attaching the timing belt cover to the end face of the engine, the heads and protrusions of the bolts come into direct contact with the elastic material, and the tightening force of the bolts is applied to the pressing area that is pressed when the bolt is tightened and the area around the pressing area. There is a non-pressing part that does not work.

Therefore, since the timing belt cover is fixed to the end face via the non-pressing portion, direct contact between the end face of the engine and the timing belt cover is prevented, and transmission of engine vibrations to the timing belt cover is suppressed. . In addition, the sealing material prevents foreign matter from entering the timing belt cover and protects the timing belt cover from deterioration and damage.

〔Example〕

An embodiment of the present invention will be described below based on the drawings.

In FIGS. 1 to 3, the structure of the present invention includes a timing belt cover 3 that covers the timing belt 2, and a sealing material 5 that seals the gap G provided between the cover 3 and the end face 4 of the engine around the entire circumference of the timing belt cover 3. In addition, by attaching an elastic member 7 to the bolt insertion hole 6 of the timing belt cover 3, the tightening force of the bolt 9 is not directly transmitted to the cover 3.

The timing belt cover 2 has pulleys 14 and 15 attached to the crankshaft 11 protruding from the lower part of the cylinder block 10 and a camshaft 13 extending from the cylinder head 12, respectively, wound around the pulleys 14 and 15, and attached to the cylinder block 10 so as to be able to freely vibrate. Supported idler 1
You can use 7 to get nervous. The timing belt cover 3 is a lightweight molded product made of synthetic resin or thin steel plate, and the timing belt cover 3 is shaped like a container and has an edge 21 facing the end surface 4 of the engine as shown in FIG. The sealing surface 21a of the edge 21, which has a large area and faces the end surface 4, is provided with a stepped groove over the entire circumference, and a string-shaped sealing material 5 made of rubber or the like is installed in the groove. While fitting, the sealing surface 21a has
A mounting seat 24 is provided extending at the upper end of the cylinder head 12 and at a lower position of the cylinder block 10. The bolt insertion hole 6 is provided in the mounting seat 24 in a protruding manner, and the elastic material 7 made of cylindrical rubber or the like is bonded to the bolt insertion hole 6 by baking, gluing, or the like.

The elastic material 7 has a cylindrical shape as described above, and the outer diameter of the outer peripheral surface is larger than the outer diameter of the head 8 of the bolt 9 head 9a or the washer 37 attached to the lower surface of the head 9a. Furthermore, the length is set to be approximately equal to the thickness of the timing belt cover 3.

On the other hand, the engine includes a cylinder block 10,
Cylinder head 12, cylinder head cover 33
A protrusion 34 having a flat outer surface and curved in the same shape as the sealing surface 21 is continuously provided through the sealing surface 21, and the outer surface thereof constitutes the end surface 4 of the engine. Further, the protrusion 34 is provided with a screw hole 35 at a position facing the mounting seat 24, and a screw hole 35 surrounding the screw hole 35, having a smaller diameter than the outer diameter of the elastic material 7, and making contact with the elastic material 7. As a result, a protrusion 36 that forms a gap G between the cover 3 and the end surface 4 is formed. Note that the protrusion 36 can be formed by attaching a seat plate having a smaller diameter than the outer diameter of the elastic material 7 to the end surface 4 .

The sealing material 5 has a protrusion length l in its free state.
However, the length is set to slightly exceed the height of the protrusion 36. Therefore, by passing the threaded part 9b of the bolt through the hole 18 of the elastic material 7 and inserting it into the threaded hole 35,
The gap G between the cover 3 and the end face 4 of the engine caused by the projection 36 can be sealed and the inside thereof can be protected. Furthermore, it is clear that the gap G restricts the pressure applied to the sealing material 5, preventing the sealing material 5 from fading, and allowing the sealing material 5 to be used repeatedly.

Furthermore, the elastic material 7 has a pressed part that is pressed between the bolt head 8 and the protrusion 36 when the bolt 9 is tightened, and a non-pressed part where the tightening force of the bolt 9 does not act around the pressed part. There is an intervention.

However, in the structure of the present invention, when attaching the timing belt cover 3 to the end surface 4, the elastic material 7 is
While there is a non-pressing part on which the tightening force of the bolt 9 does not act, the cover 3 and the end face 4 are prevented from coming into direct contact even at the tightening part.
Not only can vibrations directly transmitted from the engine via the bolts 9 be prevented, but also the timing belt cover 3 can be attached without impairing the function of the elastic member 7. In addition, since the transmission of vibration to the timing belt cover 3 can be reduced, membrane vibration can be prevented and noise can be reduced, and the sealing material 5 can prevent foreign matter from entering the timing belt 2.
Prevents deterioration and skipped stitches.

Furthermore, since the elastic material 7 has a non-pressing portion around the pressing portion, a force that spreads in the circumferential direction is applied to the elastic material 7 by the tightening force of the present invention 9, and this acting force causes the elastic material to It is obvious that the timing belt cover 3 can be prevented from falling off by increasing the bonding force between the outer diameter of the material 7 and the bolt insertion hole 6.

[Effect of idea]

As mentioned above, the structure of the present invention protects the timing belt cover with the sealing material, prevents direct contact between the end face of the engine and the timing belt cover, and suppresses transmission of engine vibrations to the timing belt cover. This prevents membrane vibration of the cover and reduces noise generation. Furthermore, since it can be easily formed, it is possible to reduce the cost of the engine. In addition, in the structure of the present invention, the bolt insertion hole may be formed in the shape of a notched groove other than a circle, and the elastic material and the cylindrical body may be formed in a non-circular shape or a tapered shape, and furthermore, a sealing material may be formed on the end face of the engine. It can be transformed into various forms such as fitting.

[Brief explanation of the drawing]

Fig. 1 is a perspective view illustrating the attachment of the cover, Fig. 2 is a sectional view showing an embodiment of the present invention, Fig. 3 is a sectional view showing the main parts thereof, and Fig. 4 is a sectional view illustrating the conventional structure. It is a diagram. 2...Timing belt, 3...Timing belt cover, 4...End face, 5...Sealing material, 6...
...Bolt insertion hole, 7...Elastic material, 8...Head, 9
... Bolt, 18 ... Hole, 21 ... Edge, 35
...Screw hole, 36...Protrusion, G...Gap.

Claims (1)

[Scope of utility model registration request] A timing belt cover mounting structure having a container shape and covering a timing belt attached to an end face of an engine by bolting an edge to the end face of the engine, wherein a bolt for mounting the timing belt cover is screwed into the end face. A protrusion is formed to surround the screw hole to be inserted and to form a gap between the timing belt cover and the timing belt cover. The belt cover has a cylindrical shape with a hole through which the threaded portion of the bolt is inserted, and the outer diameter of the outer peripheral surface is larger than the head of the bolt and larger than the outer diameter of the projection. A timing belt cover mounting structure characterized in that a bolt insertion hole is provided into which the outer peripheral surface of the material is inserted and fixed.