JPH0746842Y2 - Sealing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a seal device which is mounted between two mutually movable members to seal the inside and the outside of the two members, and more specifically, to a seal device. The present invention relates to a combined seal for improving airtightness.

[Prior Art] Conventionally, a sealing structure formed by combining a plurality of sealing materials of this type will be described with reference to the drawings. As shown in FIG. 2, a plurality of seal lips 8a.8b mounted on an outer member 1 are provided. .
A sealing element 9 provided with 8c, and a slinger having a shape surrounding the sealing lip 8a.8b.8c and attached to the inner member 3
10 and the seal lips 8a.8b.8c are slinger 10
The inner peripheral surface of the radial direction and the axial direction are slidably contacted with each other to exert a sealing action against muddy water, foreign matter, etc. that try to enter from the outside.

[Problems to be solved by the invention] However, in the sealing device as described above, even if a pressure due to thermal expansion is generated between the respective seal lips 8 during operation, the respective seal lips 8 have no relation to each other. Since it does not have it, its pressure is released to the outside without being held, and on the contrary, it shows a suction phenomenon that shrinks by cooling when the operation is stopped, and by such a breathing action, external mud can be easily put inside the sealing device. Infiltrate into.

Also, when strong sealing force is required, each seal lip
The pressure contact force of 8a.8b.8c is strengthened to cope with this, but if this is done, the sliding torque will be greatly increased and heat will be generated, which will easily damage the lip tip.

The present invention eliminates these drawbacks and is effective in blocking foreign substances and muddy water that try to infiltrate from the outside, and a seal that also has a protective measure against lubricants such as grease that try to leak from the inside. A device is provided.

[Means for Solving the Problems] The present invention, as shown in FIG. 1, includes a first sealing element 2 having a substantially L-shaped cross section, which is fixed to an outer member 1 that rotates relative to a bearing or the like, and an inner member. The cross section fixed to 3 is approximately inverted L
A sealing device comprising a second sealing element 4 in the shape of a letter, and a sealing lip made of an elastic material such as synthetic rubber or synthetic resin disposed on these elements 2.4;
A side lip 5 facing the inner diameter direction and an inner peripheral lip 6 facing the outer side in the axial direction are provided in the radial direction part of the second sealing element 4 and are slidably contacted with the radial side surface and the axial outer peripheral surface of the second sealing element 4, respectively. In addition, an axially inward lip 7 is provided on the radial direction portion of the second sealing element 4 so that the second sealing element 4 is brought into sliding contact with the axial inner peripheral surface of the first sealing element 2.

Further, as shown in FIG. 1, an axially outwardly directed lip 8 having a shape in which the axially inwardly facing lip 7 faces backward is additionally provided at a radial direction portion of the secondally sealing element 4 to provide the firstally sealing element 2. It is characterized in that it is slidably contacted to the inner circumferential surface of the.

[Operation] Since the present invention is a sealing device having such a structure, when the sealing device is integrally combined as shown in FIG.
Since the tips of the side lips 5 and the inner peripheral lips 6 of the first sealing element 2 have a shape facing each other and are in direct contact with the radial direction portion and the axial direction portion of the second sealing element 4, each lip 5 having a sealing directionality. When a thermal expansion pressure is generated in the dorsal space, 6 is in an orderly state, and the pressure is maintained between the lips to form a pressure space A1 there.

Then, the axially inward lip 7 provided on the second sealing element 4 contacts the first sealing element 2 inwardly to bring the first sealing element 2 into contact.
The inner peripheral lips 6 are opposed to each other, and a secondary pressure space A2 is formed between the lips as well, showing a function of retaining the pressure.

These pressure spaces A1 and A2 tend to swell due to the pressure, and here the contact sliding pressure of each lip 5, 6, or 7 increases, so that it is strong to block the intrusion of muddy water from the outside and the leakage of lubricating oil from the inside. It becomes a sealing force.

[Embodiment] As shown in FIG. 1, when the present invention is carried out, if an axially outwardly directed lip 8 is additionally provided outside an axially inwardly directed lip 7 provided on the second sealing element 4, direct scattering is achieved. It is effective in removing the mud and foreign substances that adhere to it, and it is possible to obtain a more reliable pressure space and maintain a high sealing force for a long period of time.

[Advantages of the Invention] As described above, the sealing device of the present invention forms the pressure space A1 for holding the pressure by the side lip 5 and the inner peripheral lip 6 facing each other in the sealing direction, and the inward lip 7 in the axial direction. With the inner peripheral lip 6, the secondary pressure space A2 is also formed, and the pressure exerts a strong sealing and blocking action in both the inner and outer directions, thereby succeeding in greatly enhancing the sealing function.

Further, the adsorption and deformation phenomenon of the lip caused by the internal and external pressure fluctuations also serves to maintain the lip shape of the pressure spaces A1 and A2 and prevent the bite adsorption.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the sealing device of the present invention. FIG. 2 is a sectional view showing a conventional sealing device. A1 ... pressure space, A2 ... secondary pressure space, 1 ... outer member, 2 ... first sealing element, 3 ... inner member, 4 ... second
Sealing element, 5 ... Cytrip, 6 ... Inner peripheral lip, 7
…… Axial inward lip, 8 …… Axial outward lip.

Claims (2)

[Scope of utility model registration request] 1. A first sealing element 2 having a substantially L-shaped cross section fixed to an outer rotating member 1 and a second sealing element 4 having a substantially inverted L-shaped cross section fixed to an inner member 3. A sealing device having elastic sealing lips arranged on these elements 2.4; side lips 5 facing inward in the radial direction of the first sealing element 2 and axially outward. Inner peripheral lips 6 facing each other and slidably contacting the radial side surface and the axial outer peripheral surface of the second sealing element 4, respectively, and further the axial inward lip 7 is provided on the radial portion of the second sealing element 4. Is provided and slidably contacted with the axial inner peripheral surface of the first sealing element 2. 2. A radial direction portion of the second sealing element 4 is provided with an axially outwardly facing lip 7 and an axially outwardly facing lip 8 which are opposed to the axially inwardly facing lip 7 and slidably contacts the axially inner peripheral surface of the first sealing element 2. The sealing device according to claim 1, wherein the sealing device is made.