JPH0239672B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention comprises an elastic body having a sealing lip preferably biased by a spring, a cylindrical reinforcing member made of metal or other material, and a cylindrical reinforcing member made of metal or other material; The present invention relates to a lip seal ring comprising a mounting punch formed on a reinforcing member and an engaging portion, and in particular to a lip seal ring for a valve shaft of a puppet valve for an internal combustion engine.

BACKGROUND OF THE INVENTION Conventionally, lip seal rings of valve shafts having spring-loaded or non-spring-loaded seal lips are secured onto guides of the valve shaft using clamps, springs, or reinforcing rings. . The reinforcing ring is made of metal or other hard material and is molded or bonded to the resilient valve shaft sealing member. During installation, the lip seal ring is pressed onto the valve shaft guide using a cylindrical installation punch. The reinforcing ring is provided with a radially outwardly extending projection so that the mounting punch can engage the reinforcing ring.

Several lip seal rings are already known in the art, in which a reinforcing ring is provided with a retaining flange or a mounting flange. For example, German Patent Application No. 1550247 discloses that the reinforcing ring is bent radially inward in the region between its holding part and the sealing lip, so that the collar formed there engages with the mounting punch. It is known that the MTZ Motortechnische
According to Zeitschrift (1975), No. 12, paragraph 1, an elastic sealing member of the valve shaft is molded or bonded to a reinforcing ring, and the reinforcing ring has a lip seal portion of a lip seal ring and a lower lip seal member. A known valve shaft lip seal ring is shown having a radially outwardly bent mounting collar formed in the middle of the section.

[Problem to be Solved by the Invention] However, a disadvantage of such a reinforcing ring with radially outwardly projecting mounting auxiliary means is that it requires a relatively large construction space, so that for example two Such reinforcing rings cannot be used in engines with valve springs whose radial assembly space is very small. Furthermore, a special problem is that the design of the mounting punch is limited if the valve shaft has already been inserted into the valve guide before the lip seal ring is pressed onto the valve shaft. In addition, such folds also have a relatively large drawing radius due to their manufacturing method, and their reinforcing rings have a relatively large dimensional intersection in the outer diameter. In order to fill this intersection, such a reinforcing ring must have an elastic material coated on its outer surface. In the case of lip seal rings with a reinforcing ring bent radially inwardly or outwardly between the sealing lip part and the fixing part, the relatively high stresses occurring during installation may cause the elastic sealing member to There is a risk that the adhesion between the reinforcing ring and the reinforcing ring is impaired, thereby ruining the entire seal.

Therefore, it is an object of the present invention to prevent the reinforcing ring from being damaged when the elastic sealing member and the reinforcing ring are press-fitted into the valve shaft, while the reinforcing ring has a slight radial direction compared to the conventional one. It is an object of the present invention to provide a lip seal ring, in particular a lip seal ring for a valve shaft of an internal combustion engine, having an edge that engages with a mounting punch while requiring only 100 yen of structural space. It is also an object of the present invention to manufacture such a lip seal ring easily and inexpensively.

[Means for Solving the Problem] This problem is achieved by providing a cylindrical elastic body having a seal lip portion at one end and a mounting portion at the other end, according to the present invention;
This is achieved by a lip seal ring consisting of a cylindrical reinforcing member (reinforcing ring) in which an annular shoulder portion is formed. This reinforcing member includes a first portion on the side of the seal lip, a second portion having a smaller diameter than the first portion and concentric with the first portion, and a second portion between the first portion and the second portion.
and a shoulder portion connected to the shoulder portion.
The inner surface of the reinforcing member is glued to a cylindrical elastic body, but its outer surface and upper edge are not covered with elastic material. The shoulder portion of the reinforcing member is preferably located in the central portion of the reinforcing member, and its length is approximately 1/5 of the total length of the reinforcing member. The radial dimension difference between the different diameter portions of the shoulder portion, when measured by the difference in radius between the first and second portions, is to the extent that it does not exceed the radial wall thickness of the reinforcing member, and is Preferably, the reinforcing members do not fit into each other. Optionally, the reinforcing ring can also deviate from a circular contour and have, for example, a polygonal shape, so that a radial spring is formed so that the elastic sealing lip member is elastic. The range of acceptable dimensions between the lower portion of the body and the valve guide is increased, and the lip seal member can be easily seated on the valve guide. Oval reinforcing rings have proven advantageous in other cases, especially for reasons of manufacturing technology. Such a deviation from a circular profile can be formed if necessary only in the second part of the reinforcing ring.

Effect: By forming an annular pleat-shaped shoulder on the reinforcing element instead of a collar according to the prior art, the radial space can be utilized to the maximum due to its small diameter tolerances. The installation force is
From the mounting punch received in the upper edge of the reinforcing member facing towards the lip seal, the punch can easily be removed from the reinforcing member, although in this case the punch rests only on the small annular end face of the reinforcing member. transmitted to. The present invention provides a method for installing the lip seal ring of the valve shaft onto the valve guide in the mounting punch, even if the valve has already been inserted into its valve guide for reasons of manufacturing technology. Damage to the lip seal ring can be prevented by properly guiding the seal lip ring and using a sufficiently sized seal lip and spring. According to the present invention, the bond between the elastic body and the reinforcing member is not easily broken unlike the conventional bond. This is because the adhesive area between the elastic body and the reinforcing member can be made larger, thereby providing better resistance to such damage.

The lip seal ring according to the invention, which should preferably be applied in valve shafts of relatively small diameter, can in principle also be used with different lip seal rings having generally similar dimensions and installation problems. can.

[Example] The present invention will be described in more detail below with reference to the attached FIGS. 1 to 4.

Figure 1 shows a lip seal ring 1 for sealing a valve shaft.
is a cylindrical elastic body 6 having a seal lip portion 7;
and a reinforcing ring 9 which is a reinforcing member located below the elastic body. Annular seal lip spring 8
fixes the seal lip portion 7 to the valve shaft 3. Only the inner surface of the cylindrical reinforcing ring 9 is bonded to the elastic body 6. The lip seal ring 1 is press-fitted into the valve shaft 3 and valve guide 5 in the direction of the arrow 4 using a mounting punch 2. A base surface 12 is formed at the upper end edge of the cylindrical reinforcing ring 9 . The reinforcing ring 9 further includes a first portion 15 located on the side of the sealing lip 7 and a second portion 17 having a smaller diameter than the first portion. The first part 15 and the second part 17 are concentrically connected by an annular pleat or a shoulder part 10 of different diameter. The mounting punch 2 has a notch 11 having a radial contact surface, and when the lip seal ring is installed, the force is transferred from the contact surface of the notch 11 of the punch 2 to the seal lip 7 of the reinforcing ring 9. is transmitted to the base surface 12 of the upper edge of the side.

FIG. 2 is a cross-sectional view of the reinforcing ring 9 having a circular second portion 17, and FIG.
The reinforcing ring 9' having the section 17 is also
The figures show a reinforcing ring 9'' with a second part 17 of octagonal cross-section, but in all these cases the third,
In the case of the embodiment shown in FIG. 4, the outer peripheral surfaces in contact with the second portions of the elastic bodies 6', 6'' are elliptical or octagonal in accordance with the shape of the second portions 17 of the reinforcing rings 9', 9''. However, the inner peripheral surfaces of the elastic bodies 6', 6'' are circular.

[Effects of the Invention] As explained above, the invention of the present application forms an annular pleated shoulder portion in the center of the elastic member of the lip seal ring, and forms a shoulder portion in the form of an annular pleat at one end edge of the reinforcing member. Provides an annular base surface that receives force,
By adhering the inside of the other end to an elastic body that is a lip seal member, the following effects can be achieved.

(1) Since the outer diameter of the shoulder portion of the reinforcing member can be made smaller than that of the conventional bent brim shape, it is possible to reduce the radial constituent chambers of the base surface that receive the force of the punch. Can be applied to narrow assembly spaces.

(2) Since the annular pleat-shaped reinforcement part is formed in the center of the reinforcement member, it provides a large resistance to deformation of the reinforcement ring due to the force applied from the punch during installation work, and also Since the adhesive area between the reinforcing ring and the elastic body is large, the adhesion between the reinforcing ring and the elastic body is less likely to be impaired compared to a conventional reinforcing ring having a bent portion.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view illustrating the installation state of a valve shaft gasket according to the present invention, and FIGS. 2 to 4 are first views of a lip seal ring having reinforcing rings with different cross-sectional shapes attached to the valve shaft. A sectional view taken along the - line is shown. 1... Lip seal ring, 2... Punch for installation, 3... Valve shaft, 5... Valve guide, 6, 6', 6''... Elastic body, 7... Seal lip portion, 8... Seal lip Spring, 9,9',
9″...Reinforcement member (reinforcement ring), 10...Shoulder portion, 11...Cutout portion, 12...Base surface, 15...
...first part, 17...second part.

Claims (1)

[Claims] 1. A cylindrical elastic body that is mounted using a mounting punch on a cylindrical valve guide provided around the valve shaft of a poppet valve of an internal combustion engine, and a metal or other In a lip seal ring for sealing a valve shaft, the cylindrical elastic body 6 has a seal lip part 7 at one end and a mounting part at the other end, A cylindrical reinforcing member 9 has an annular base surface positioned such that the mounting punch 2 comes into contact with one axial end located on the side of the seal lip portion 7 and transmits force from the punch. 12 is formed in an axially extending cylindrical first portion 15;
It consists of a cylindrical second part 17 extending coaxially with the part 15 and having a smaller diameter than the first part 15, and an annular shoulder part 10 connected to the first part 15 and the second part 17, 1st part 15, 2nd part
The radial thickness of the section 17 and the shoulder section 10 are substantially equal, and the reinforcing element 9 surrounds the lower mounting part of the elastic body 6 and only its inner surface is glued to the mounting part. Lip seal ring for seals. 2. The annular shoulder portion 10 is located approximately in the axial center of the reinforcing member 9, and its length is at most 1/5 of the total length of the reinforcing member 9. Lip seal ring. 3. The lip seal ring according to claim 1 or 2, wherein the radial height of the annular shoulder portion 10 is at most approximately equal to the wall thickness of the reinforcing member 9. 4. The lip seal ring according to any one of claims 1 to 3, wherein the reinforcing members 9', 9'' have a cross-sectional shape that deviates from a circular shape.5. The lip seal ring according to any one of claims 1 to 4, having a cross-sectional shape. 6. The lip seal ring according to any one of claims 1 to 4, wherein the reinforcing member 9' has an oval cross-sectional shape. 7. The cross-sectional shape of the reinforcing members 9', 9'' deviates from a circle only in the portion facing the elastic body 6, according to any one of claims 1 to 6. Lip seal ring.