JPH038829Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a cover member and gasket with improved tightening and sealing properties, and more specifically to an improved combination shape of the cover member and gasket.

[Conventional technology]

Gaskets are used to create a seal by interposing the seal between two parts, but conventionally large gaskets with complex shapes are used for relatively large sealing points, such as oil pans used in automobile engines. With gaskets such as gaskets and valve cover gaskets, uniform tightening surface pressure cannot be obtained due to uneven tightening force during assembly and lack of accuracy of the cover member. When using a cover member, if too much tightening pressure is applied, only the area around the bolt hole will deform excessively, and if a gasket is compressed by more than 50% of its thickness before tightening, abnormal extrusion or cracks may occur. arise and vice versa 10
If the clamping pressure is less than %, the surface pressure will be insufficient, and the sealing performance will be severely compromised.

A detailed description will be given below with reference to the drawings.

As a countermeasure to this drawback, as shown in Figure 4,
Protrusions 2 protruding lower than the thickness of gasket B are provided at multiple locations on the sealing surface 1 of cover member A, and the protrusions 2
Gasket B has a fitting hole 3 at the position where it is fitted.
A device has been devised in which a cover member A is attached and tightened to prevent partial deformation due to over-tightening of the cover member A.

[Problem that the invention attempts to solve]

However, in the above structure, since the protrusion 2 is provided in the middle of the sealing surface 1 of the cover member A, the cover member A
The sealing surface 1 tends to be distorted when forming or tightening the gasket B, resulting in a significant decrease in planar accuracy, and the sealing area of the gasket B itself is narrowed, which is a serious drawback in that the sealing force is reduced. Further, the protrusion 2 simply protrudes to one side, and has a shape that makes it difficult to use an accurate machining process, resulting in low accuracy in the height dimension, which is extremely important for tightening regulation.

The present invention provides a structure for cover member A and gasket B that eliminates these drawbacks, prevents excessive tightening with a simple structure, and can apply uniform tightening surface pressure to gasket B over a long period of time.

[Means for solving problems]

As shown in FIG. 1, the present invention includes a cover member A1 having a plurality of bolt mounting holes 4 on the sealing surface 1, and a bolt insertion hole 5 provided at approximately the same position as the bolt mounting holes 4 of the cover member A1. The cover member A has a combination structure with a gasket B1 formed of an elastic body such as cork, synthetic rubber, or synthetic resin;
1 bolt mounting hole 4 circumferential edge to seal surface 1 within the range up to the height of the optimal compression dimension of gasket B1.
The folded portion 6 is formed by bending at an angle of 90° or more.
The gasket B1 is provided with a bolt insertion hole 5 having a shape into which the folded portion 6 can be inserted, and the bolt insertion holes 5 are combined to form a seal.

The cover member A1 forming this folded portion 6 is
It is common, and most of the time, to be shaped from steel plates, which are easy to bend and draw and are inexpensive, but synthetic resins reinforced with fibers are used to achieve higher soundproofing and lighter weight. There is no problem.

[Effect]

When this gasket B1 is assembled to the cover member A1 and this is attached and tightened to the sealing member 8, as shown in FIG. Before the end of tightening, the gasket B1 is compressed between the two, and eventually the gasket B1 is elastically deformed and compressed to its optimum tightening dimension. This is because the height of the folded portion 6 is set in advance so as to apply appropriate surface pressure to the gasket B1 when tightened, and when the optimum tightening pressure is reached, the distance between the folded portion 6 and the opposing sealing member 8 is regulated. Maintain constant surface pressure.

In this way, the folded part 6 is located directly under the bolt 7, which receives the tightening pressure and regulates the compression dimension, so the cover has the highest risk of deformation, buckling, and torque reduction. The vicinity of the bolt attachment hole 4 of the member A1 and the vicinity of the bolt insertion hole 5 of the gasket B1 are not distorted.

The compressive surface pressure obtained in this way maintains a smooth sealing surface 1 without deforming the local part of the cover member A due to over-tightening as in the past, and provides a stable and strong seal for a long period of time with the optimum surface pressure. to do.

In addition, in terms of installation workability, in the past it was impossible to accurately mount the gasket B on the cover member A without inserting and positioning the bolts 7, but in the present invention, the bolt mounting holes 4 of the cover member A1 are A plurality of folded portions 6 provided in the gasket B1
Since the structure is such that the gasket B1 fits into the bolt insertion hole 5 of the cover member A1, the gasket B1 is brought into close contact with the sealing surface 1 of the cover member A1, and also has the effect of preventing the gasket B1 from falling off by holding the gasket B1 itself.

Another function is the bending angle of the folded part 6, which has a spring elasticity inside it even if it is tightened unless it is fully folded. It constantly directs repulsive force and shows a strong effect in preventing loosening.

〔Example〕

Regarding the shape of the folded part 6 provided on the cover member A1, in FIG.
Although sufficient resistance to excessive tightening pressure has been achieved, if an extreme load is not applied, a part of the peripheral edge of the bolt mounting hole 4 can be bent and folded back as shown in Fig. 3. By using the piece 6a, a more advantageous sealing area can be obtained. Naturally, this folded piece 6a
It is only necessary to set the number and the contact area thereof depending on the tightening load to be applied, and it is not enough to simply bend it into a single layer, but also to bend it into other shapes such as a coiled shape or a bulge shape (not shown in the figure). There is no problem.

[Effect of idea]

By providing the folded part 6 with a strong dimensional control force on the cover member A1, the normal tightening dimension is always achieved no matter what the tightening situation is, and as mentioned above, no precautions are required, so it is easy to install. Workability is very good.

As explained above, the present invention is an ideal cover member and gasket structure that has a simple structure, greatly improves sealing performance and tightening performance, and also prevents material aging.

[Brief explanation of the drawing]

FIG. 1 is a partial perspective view showing the cover member and gasket of the present invention. FIG. 2 is a partial sectional view showing the state in which the cover member and gasket of the present invention are attached. FIG. 3 is a partial perspective view showing another embodiment of the cover member of the present invention. FIG. 4 is a partial perspective view showing the structure of a conventional cover member and gasket. A...Cover member, B...Gasket, 1...
Seal surface, 4... Bolt mounting hole, 5... Bolt insertion hole, 6... Turned part, 7... Bolt.

Claims (1)

[Scope of utility model registration request] A cover member A1 having a plurality of bolt mounting holes 4 on a sealing surface 1, and a bolt insertion hole 5 provided at approximately the same position as the bolt mounting holes 4 of the cover member A1, and an elastic material such as cork, synthetic rubber, or synthetic resin. A combination structure with a gasket B1 formed of;
A part or the entire circumference of the bolt mounting hole 4 in the cover member A1 is at least 90° or more with respect to the sealing surface 1 of the cover member A1 within a dimension range that is 10% to 50% less than the thickness dimension of the gasket B1. The folded part 6 is formed by bending the folded part 6 at an angle of
The structure of the cover member A1 and gasket B1 is characterized in that the gasket B1 is provided with a bolt insertion hole 5 shaped to allow the insertion of the bolt and the bolt insertion hole 5 is combined with each other.