JPH03189478A - lip seal device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a lip seal device that includes a lip seal that slides into contact with a rotating shaft.

"Prior Art" Conventionally, a lip seal device includes a cylindrical case, a support part and a caulking part formed in the case and facing each other, and an outer circumferential part housed in the case and connecting the support part and the caulking part. A lip seal is known which is sandwiched between the lip seals and has an inner circumferential portion curved toward the sealing fluid side and slidably contacts the outer circumferential surface of a shaft passing through the case.
Publication No. 33058).

``Problems to be Solved by the Invention'' In the lip seal device described above, the outer circumferential portion of the lip seal is compressed and elastically deformed in the axial direction by the caulking portion and the support portion, so that the caulking portion is moved radially inward. When bending and caulking, the bending position shifts in the axial direction, causing variations in the axial length of the case.

Furthermore, if the bending position of the caulked portion is misaligned in the axial direction or there is an error in the radially inward bending angle of the caulked portion, the amount of compression of the lip seal will vary.
If the amount of compression is insufficient, there is a risk that the lip seal will rotate relative to the case or fall off, and if the amount of compression is too large, the lip seal will deteriorate rapidly.

[Means for Solving the Problems] In view of such circumstances, the present invention provides the lip seal device described above, in which when the caulking portion is caulked between the support portion and the caulking portion, the caulking portion and the caulking portion are connected to each other. A spacing regulating member having a predetermined length is provided to maintain a predetermined distance from the support portion.

"Operation" According to the above configuration, the distance regulating member allows the axial distance between the support part and the caulked part to be maintained constant after assembly is completed, and therefore the axial dimension of the case and the lip seal can be maintained constant. The amount of compression can be managed with high precision.

``Embodiment'' The present invention will be described below with reference to an illustrated embodiment. In FIG. This is to prevent leakage of the liquid to the outside from the hole 3a.

The lip seal device 1 is equipped with a stepped cylindrical case 5 made of steel, and an O-ring is attached to the outer periphery of a small diameter portion 5a of the case 5 on the outside of the housing 3 (left side in FIG. 1). I am wearing 6.

Additionally, three glue tabs are attached to the inside of the large diameter portion 5b on the inside of the housing 3 in the case 5 (right side in Figure 1).
The first lip seal 7, the spacer 10, the second lip seal 8, and the third lip seal 8.9 and the spacer 10, which also serves as a spacing regulating member, are arranged in the order from the outer side to the inner side.
A support portion 5 is formed by axially overlapping and storing the lip seals 9 in the order in which the outer periphery of the lip seals 9 is formed in the middle step of the case 5.
It is clamped and fixed in the axial direction by C and the caulking part 5d at the right end.

Then, the outer circumferential surface of the large diameter portion 5b of the case 5 is fitted into the hole 3a of the housing 3, and the O-ring 6 attached to the outer circumference of the small diameter portion 5a is brought into close contact with the inner circumferential surface of the hole 3a. At the same time, as shown by imaginary lines, the seal portions located on the inner periphery of each lip seal 7, 8, 9 held in the case 5 are attached to the case 5.
It is slidably brought into close contact with the outer circumferential surface of the rotating shaft 2 through which it passes, so that the liquid-tightness of that part is maintained.

The caulking portion 5d of the case 5 is formed from the tip end side of the large diameter portion 5b, and in the state before assembly, the caulking portion 5d
d extends in the axial direction integrally with the large diameter portion 5b, and by setting the thickness of the caulking portion 5d to a dimension tl that is thinner than the thickness t2 of the large diameter portion 5b and the support portion 5C, the caulking The portion 5d can be easily bent radially inward.

However, as shown in FIG. 2, the first lip seal 7 disposed on the leftmost side in the case 5 is made of rubber, and the left end surface 7a of the outer circumference of the first lip seal 7 is provided with a seal of the case 5. A first spacing regulating member 14 made of a ring-shaped steel material that abuts the support portion 5C is integrally vulcanized and electrically connected.

The outer diameter of the first spacing regulating member 14 is slightly smaller than the inner diameter of the large diameter portion 5b of the case 5. In this embodiment, the outer circumferential portion 14 of the first spacing regulating member 14 on which the annular protrusion 14a is formed
The axial length at b is set to a predetermined dimension I21.

The first spacing regulating member 14 and the first
Lip seal 7 is the first lip seal in the natural state shown in FIG.
The right end surface 7b of the lip seal 7 is set to protrude inward from the housing 3 by a predetermined distance I22 from the tip of the annular projection 14 of the first interval regulating member 14.

Therefore, the first lip seal 7, which protrudes inward from the annular projection 14a of the first spacing regulating member 14 by the above-mentioned dimension 22, is pressed in the axial direction by the spacer IO during assembly and is elastically deformed. and the end face of the spacer lO, which also serves as a spacing regulating member, is an annular protrusion 1.
By coming into contact with 4a, the amount of elastic deformation of the first lip seal 7 can be restricted.

Further, a space 7c is formed in the outer periphery of the first lip seal 7 and is continuously cut out in the circumferential direction. I try not to get caught up in it.

Further, the inner circumferential side of the first lip seal 7 is formed into a lip shape with a thickness thinner than the outer circumferential side to which the first spacing regulating member 14 is attached, and the tip of the lip is attached to the rotating shaft. The seal portion 7d is in close contact with the outer circumferential surface of 2.

Next, the spacer IO is formed into a ring shape from a steel material having a uniform thickness t3, and its outer diameter is set to be substantially the same as the inner diameter of the large diameter portion 5b of the case 5. The inner circumferential side of the spacer IO is a conical guide portion 10a that protrudes to the right, and the inner diameter thereof is set to be larger than the outer diameter of the rotating shaft 2 by a required amount. The inner peripheral portion of the second lip seal 8 can be curved along this guide portion 10a.

The second lip seal 8 is manufactured in a ring shape from PTFE with a uniform thickness, and its outer diameter is set to be substantially the same as the inner diameter of the second gap regulating member 15, which will be described next. The two lip seals 8 can be housed within the second spacing regulating member 15. Then, the inner diameter of the second lip seal 8 is set smaller than the outer diameter of the rotating shaft 2, so that the inner circumferential portion of the second lip seal 8 is brought into close contact with the outer circumferential surface of the rotating shaft 2, and a seal portion 8a is formed there. I have to.

Furthermore, the third lip seal 9 is manufactured from rubber,
A cylindrical second spacing regulating member 15 is integrally vulcanized and bonded to the outer circumferential portion thereof. At this time, an embedded portion 1 is formed on the inner peripheral surface of the cylindrical second interval regulating member 15 so as to protrude radially inward.
5a is embedded in the outer peripheral portion of the third lip seal 9.

The second spacing regulating member 15 and the third lip seal 9 are as follows:
In the natural state shown in FIG. 2, the left end of the cylindrical portion 15b of the second spacing regulating member 15 protrudes to the left by a predetermined amount beyond the left end surface 9a of the third lip seal 9. It becomes. On the other hand, the right end surface 9b of the third lip seal 9 protrudes inward from the housing 3 by a predetermined dimension β3 beyond the right end of the cylindrical portion 15b of the second spacing regulating member 15. That's what I do.

The axial length of the cylindrical portion 15b of the second spacing regulating member 15 is set to a predetermined dimension β4, and the outer diameter of the cylindrical portion 15b is substantially equal to the inner diameter of the large diameter portion 5b of the case 5. Furthermore, the inner diameter of the cylindrical portion 15b is set to be large enough to accommodate the outer peripheral portion of the second lip seal 8.

Then, as shown by the imaginary line in Figure 2, the second
The lip seal 8 is attached to the cylindrical portion 15b of the second interval regulating member 15.
In the state in which the second lip seal 8 is fitted into the second lip seal 8 and in contact with the end surface 9a of the third lip seal 9, the left end surface 8b of the second lip seal 8 is aligned with the cylindrical shape of the second spacing regulating member 15. He is trying to project to the left by a predetermined amount from the end of the portion 15b.

A space 9C is formed in the outer periphery of the right end surface 9b of the third lip seal 9, and is continuously cut out in the circumferential direction.
This prevents the spacer from being caught between the distance regulating member 15 and the caulked portion 5d. In addition, the third lip seal 9
There is also a space 9c similar to that described above on the outer periphery of the left end surface 9a.
is formed to prevent this portion from being caught between the second spacing regulating member 15 and the second lip seal 8.

Further, the inner diameter of the third lip seal 9 is smaller than the outer diameter of the rotating shaft 2, so that the inner circumferential portion of the third lip seal 9 is brought into close contact with the outer circumferential surface of the rotating shaft 2, and the seal portion 9d is attached thereto. I'm trying to form it.

In the above configuration, when assembling the lip seal device 1, the first lip seal 7 is fitted into the large diameter portion Sb of the case 5, and the first gap regulating member 14 adhered to the outer circumference of the first lip seal 7 is supported by the case 5. It is brought into contact with the portion 5c. Thereafter, the spacer IO and the lip seal 8.9 are sequentially fitted into the large diameter portion 5b, and the outer peripheral portions of the members fitted into the large diameter portion 5b are overlapped.

When this state is reached, the caulked portion 5d of the case 5 is bent radially inward from a predetermined position in the axial direction, and the caulked portion 5d is
The outer circumferential portion of each member housed in the large diameter portion 5b is strongly pressed and held in the axial direction by the support portion 5c and the support portion 5c. As a result, each lip seal 7.8.9 becomes compressed, but between the caulked portion 5d and the support portion 5c, there is a highly rigid first spacing regulating member 14, a spacer 1o that also serves as a spacing regulating member, and a spacer 1o that also serves as a spacing regulating member. 2
Since the spacing regulating members 15 are clamped in an axially connected state, each lip seal 7.8.9 can be individually compressed by a suitable amount.

Further, the axial dimensions of the caulked portion 5d and the support portion 5C after assembly are completed include the axial dimension I21 of the first spacing regulating member 14 having high rigidity, the thickness t3 of the spacer 10, and the thickness t3 of the second spacing regulating member 15. Since it is obtained by the axial dimension I24, the axial dimension of the entire case 5 can be managed with high precision.

In this embodiment, the lip seal is made up of three members, and two spacing regulating members 14 and 15 and the spacer lO are provided, but the lip seal is made up of a single member, and the A single lip seal may be provided with an appropriate number of spacing regulating members.

Next, a second embodiment of the present invention will be described based on FIGS. 3 and 4. In contrast to the first embodiment in which the distance regulating members are connected on the outside of the lip seal, in this embodiment, the distance regulating members are connected through the lip seal.

That is, in this embodiment, the annular protrusion 114a of the first interval regulating member 114 is formed radially inward from its outer circumferential edge, and the right end surface 1 of the first interval regulating member 114
The first lip seal 1 (17) is vulcanized and bonded to the lip seal 14b. Therefore, the first lip seal 107 is cut in the circumferential direction at the position where the annular protrusion 114a is provided, and the cut portion 107 b and annular projection 114
A continuous space in the circumferential direction as in the first embodiment described above is provided at the contact portion with a.

The axial dimension of the first spacing regulating member 114 including the annular projection 114a is set to 21, and in the natural state shown in FIG.
The cutting portion 107b is in a retracted state.

In this second embodiment, the outer circumferential edge 107c of the first lip seal 107 covers the right side portion of the outer circumferential portion 114c of the first gap regulating member 114, and The large diameter portion 105b of the case 105
It is set slightly larger than the inner diameter of. Therefore, when assembling the lip seal device 101, the outer peripheral edge 107c of the first lip seal 107 is
sb and comes into close contact with the inner circumferential surface of the large diameter portion 105b.

The second spacing regulating member 115 is made of a ring-shaped steel material, and has an annular protrusion 115a continuous in the circumferential direction on its right side, and a plurality of cylindrical engagements that are not continuous in the circumferential direction on its left side. A mating convex portion 115b is formed. The dimension from the tip of the engagement protrusion 115b to the tip of the annular protrusion 115a, that is, the axial dimension of the second interval regulating member 115, is β2, and the annular protrusion 114a of the first interval regulating member 114 and the second As shown in FIG. 3, the engaging convex portion 115b and the annular projection 115a of the interval regulating member 115 are formed so that they can be arranged in a straight line in the axial direction when the lip seal device 101 is assembled.

A portion of the second spacing regulating member 115 that extends inward and outward in the radial direction is an embedded portion 115C, and this embedded portion 115
A third lip seal 109 is integrally vulcanized and bonded so as to cover c. This third lip seal 109 is cut into a radially inner portion and an outer portion at the position of the annular projection 115a, and the annular projection 115 is located within the cut portion 109a.
The tip of a is recessed into the cut portion 109a. As shown in FIG. 4, the cutting portion 109a is
It is formed into a tapered surface shape that expands on the right side, and when assembling the lip seal device 101, the third lip seal 109
After assembly is completed, the cut portion 109a is connected to the annular protrusion 115a and the caulked portion 10.
I try not to get caught between it and 5d.

On the other hand, the tips of the plurality of engagement protrusions 115b are
The end surface 109b of the third lip seal 109 is made to protrude outward by a predetermined distance from the left side end surface 109b of the third lip seal 109, and is in contact with the inner and outer circumferential portions of each engagement convex portion 115b.
A space 109C is formed in the space. And each engagement convex part 1
The second lip seal 108 is aligned with the formation position of the lip seal 15b.
A through hole 108c is formed through which each engagement convex portion 115b passes.

Further, the outer diameter of the third lip seal 109 is set so that the outer diameter of the portion in contact with the left end surface 109b is slightly larger than the inner diameter of the large diameter portion 105b of the case 105, It is made to come into close contact with the inner circumferential surface of the portion 105b (see FIG. 3).

In the above configuration, the lip seal device 1 of the second embodiment
When assembling 01, each engaging protrusion 115b of the second spacing regulating part 115 is fitted into each through hole 108c of the second lip seal 108 in advance, and the same procedure as in the first embodiment described above is performed. The lip seal device 101 may be assembled in this order.

When the assembly is completed, the annular protrusion 114a of the first spacing regulating member 114 and the engaging convex portion 11 of the second spacing regulating member 115 are formed on both end surfaces of the spacer 110 as a spacing regulating member.
5b come into contact with each other, and at the same time, the first
The spacing regulating member 114 comes into contact with the support portion 105c of the case 105, and the annular protrusion 115a of the second spacing regulating member 115 comes into contact with the caulking portion 105d of the case 105, respectively.

Therefore, the distance between the supporting portion 105c and the caulking portion 105d of the case 105 is determined by the axial dimension βl of the first spacing regulating member 114, the thickness t3 of the spacer 110, and the axial dimension 2 of the second spacing regulating member 115. Therefore, it is clear that the configuration of the second embodiment also provides the same effects as those of the first embodiment described above.

Although the annular projection 114a of the first interval regulating member 114 and the annular projection L15a of the second interval regulating member 115 are both formed continuous in the circumferential direction, they do not necessarily need to be continuous in the circumferential direction.

"Effects of the Invention" As described above, according to the present invention, the distance in the axial direction between the supporting part and the caulking part can be maintained constant after assembly is completed by the interval regulating member, so that the distance in the axial direction of the case can be maintained constant. The dimensions can be manufactured with high precision, and the amount of compression of the lip seal can be controlled with high precision to effectively prevent the lip seal from rotating or falling off from the case, or from reducing durability. can get.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing one embodiment of the present invention, and FIG.
3 is a sectional view showing another embodiment of the present invention; FIG. 4 is a sectional view showing the main part of FIG. 3 before assembly. be. 14.114...First interval regulating member 15.115...Second interval regulating member

Claims (1)

[Scope of Claims] A cylindrical case, a supporting part and a caulking part formed in the case and facing each other, and an outer peripheral part thereof is housed in the case and sandwiched between the supporting part and the caulking part, and In a lip seal device comprising a lip seal whose inner circumferential portion is curved toward the sealed fluid side and is in sliding contact with the outer circumferential surface of a shaft passing through the case, the caulking portion is provided between the support portion and the caulking portion. A lip seal device characterized in that a gap regulating member having a predetermined length is provided to maintain a predetermined distance between the caulked portion and the support portion when the lip seal device is caulked.