JPH0686909B2 - Small seal - Google Patents

Description

FIELD OF THE INVENTION The present invention relates generally to seals, and more particularly to seals useful in harsh environments and those seals used in conjunction with mechanical structures.

2. Description of the Related Art Axle bearings of vehicles running on the road are exposed to harsh environments such as moisture, dust, mud, and gravel. This is especially true in the case of light trucks and other four-wheel drive vehicles, i.e. vehicles traveling on dirt roads or off road. The seal used in the axle bearing of a conventional four-wheel drive automobile is composed of two types of radial lips called a first lip and a second lip, both of which are in contact with a cylindrical sealing surface. The first lip is provided on the lubricant side of the seal and defines the inside of the bearing and carries a garter spring that strongly biases the seal surface, thereby bearing a very effective lubricant along the seal surface. Form a barrier for retention within. The second lip is molded of elastomer and is biased against the sealing surface by the natural bias of the elastomer to similarly form another barrier along the sealing surface. However, this additional barrier is formed away from the inside of the bearing to eliminate the ingress of foreign matter into the bearing. However, in such a configuration, the first lip is very effective, so that the second lip has a problem that the lubricant is insufficient and the second lip is overheated. Along with this, the second lip hardens and gradually loses its function as a barrier, so that the intrusion of foreign matter occurs.

Since axle bearings in four-wheel drive vehicles are typically exposed to very harsh environments, it is not uncommon to have additional auxiliary seals on the outside of the second lip. However, although such an auxiliary seal may act as another holding means, it forms a pocket, and if the operation of the auxiliary seal is not perfect, water or other foreign matter may be trapped in the pocket, resulting in The action of the seal deteriorates. If such a situation occurs, the bearing will become unusable during its original life.

With or without auxiliary seals, radial lip seals conventionally used to protect axle bearings in off-road vehicles typically have a much shorter life than the bearings protected thereby. Even if the seal does not work, it is rarely noticed by the user of the vehicle, and when a seal defect is found, the bearing is often unusable due to the end of its life. Therefore, when a defect is found in the seal, it is often necessary to replace not only the seal but also the bearing.

The bearings used on the axles of large trucks and trailers used on the road must also meet the same stringent requirements for durability and foreign matter. However, in the case of off-road vehicles, seals hold grease, whereas at least road truck seals used on US highways are used to hold oil. For this reason, the bearing is provided with a simple sight glass made of glass so that the oil level can be easily checked. However, in the case of grease, there is no simple inspection method, and therefore, in order to lubricate the axle bearing, the holding inspection must be performed according to a predetermined schedule. If this is neglected, the bearing will run out of oil. On the other hand, oil is more difficult to hold than grease,
Also, the lips of seals designed to exclude foreign matter cannot be effectively lubricated. As a result, the wear of the lip becomes severe, and the effect as a barrier for blocking the entry of foreign matter is reduced accordingly. Obviously, grease is also a good car bearing lubricant for large highway trucks, as long as it is not difficult to determine how much is left in the bearing.

Sealed rotary roller bearings are gaining widespread acceptance and are being replaced by conventional bearings protected by seals attached to the wheel stops in which the bearings are installed.
To facilitate this conversion, the sealed rotating roller bearing must fit snugly in the place where the conventional bearings were previously, and must also be able to hold the seal and carry the same load. The seal must be installed in a relatively small area at the end of the bearing to effectively retain the lubricant and eliminate foreign material. Since the roller rotates in an environment where there are many gravel particles and splashes, various foreign substances are present, and if they enter the bearing, they are extremely harmful.

Means and Actions for Solving the Problems The seal assembly of the present invention is fitted to the end portion of the bearing, and is very effective as a shielding means against not only intrusion of foreign matter but also leakage of grease-like lubricant. Becomes 2 of this seal
The two lips abut the metal sealing surface and are appropriately lubricated so that they do not wear excessively. This seal does not require the provision of a very effective second seal to isolate the interior of the bearing from foreign matter. Unlike the prior art, this seal assembly alone has all the sealing functions and can be installed as a unit in the bearing.

Embodiments Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the same reference numerals denote the same parts. Tapered roller bearing A (FIG. 1) is closed at its ends by a seal B and a cooperating shield C, both of which are fitted into bearing A and form part thereof. The seal B and the shield C are further held together as parts of the bearing A, which contributes to the integration of the bearing A in that the parts do not have to be handled separately. Bearing A
Is very small, but it excels in the large carrying capacity and durability that are characteristics of the tapered roller bearing. Therefore, the bearing A fits the wheels of the vehicle.

Bearing A (FIG. 1) includes a cup 2 provided inside a surrounding structure, such as a wheel hub. The cup 2 has an inwardly facing raceway 4 which leads to an outwardly opening cylindrical counterbore 6 at the end of the cup 2. The cup 2 encloses a cone 8 fixed on a shaft or spindle, which has a tapered raceway 10 facing and encircling the raceway 4 of the cup. The outside of the cone raceway 10 leads to a thrust rib 12 having a larger diameter cylindrical outward facing surface 14 which leads further to the end of the cone 8 known as the cone back.
The thrust rib 12 becomes a part of the cone 8 and has a cylindrical surface 14
Is inside the counterbore 6 at the end of the cup 2 and its rear surface faces a nut or other support on the shaft to hold the cone 8 from moving axially outward from the cup 2.

In addition to the cup and cone 8, the bearing A has tapered rollers 16 (FIG. 1) which are arranged continuously between the raceway 4 of the cup 2 and the raceway 10 of the cone 8. The rollers 16 are brought into contact with the thrust ribs 12 of the cone 8 along these large diameter end faces, and the thrust ribs 12 prevent the rollers 16 from rolling out between the raceways 4 and 10 when a radial load is applied. It is preventing. Roller 16 is cage
Included within 18, which maintains proper spacing with adjacent rollers 16 and also retains rollers 16 around cone 8 when removing cone 8 from cup 2. The cage 18 has a large-diameter end side ring extending across the large-diameter side end surface of each roller 16, and this ring projects toward the counter bore 6 at the end of the cup 2. The tapered roller 16 and the cage 18 rotate and move inside the cavity 20 which is separated and sealed by the seal B and the shield C.

The cup 2 and the cone 8 are coaxially provided around the rotation axis x of the bearing A, and when used as a typical wheel bearing for a light truck, the cup 2 is fixed and the roller 16 is rotated. This relative rotation causes the tapered rollers 16 to move along the raceways 4 and 10 and to reduce friction, particularly between the large diameter end surface of the rollers 16 and the thrust ribs 12 of the cone 8, in the annular cavity 20. Grease is supplied to the interior as a lubricant. The tapered roller 16 is actually a thrust rib lubricant.
I try to push it toward 12. The seal B and shield C generally occupy the surface of the cup counterbore 6 and the cylindrical surface 14 of the cone thrust rib 12 to prevent lubricant leakage. The seal B and the shield C further remove dust, water, and other foreign matter from the inside of the bearing A. Therefore, the seal B and the shield C separate the annular cavity 20 existing between the cup 2 and the cone 8 from the outside. Inside the hollow portion 20, there are tapered rollers 16, and due to the friction of the rotational movement of the rollers 16,
The internal temperature of the cavity 20 changes greatly. However, since the seal B can ventilate the inside and the outside of the cavity 20, even if the air temperature in the cavity 20 changes, the pressure in the cavity 20 is not significantly affected. The seal B and the shield C together form a seal assembly.

First, consider the shield C. It is fitted on the thrust rib 12 on the cone 8 and has an annular cavity 20 (Fig. 2).
It provides a sealing surface 22 which establishes a shield with the seal B at the end of the. To this end, each shield C is generally rigid and preferably has a flange 26 radially projecting from the end of the axial mount 24, which is the end remote from the axial mount 24, cavity 20; And a curl 28 which is not so long as the flange 26 but protrudes outward in the radial direction from the other end of the axial mounting portion 24, and is formed by a metal punching material. The sealing surface 22 is along the axial portion 24 and the flange 26 (FIG. 2). The shield C is press-fitted onto the thrust rib 12 of the cone 8 and its axial portion 24 and thrust rib 12
An interference fit is made between the face 14 and the face 14. The flange 26 is flush with the back surface of the cone 8 or slightly inward. The shield C is partly the counterbore 6 of the cap 2.
However, it does not project radially enough to contact the cap 2.

Each seal B (FIG. 2) includes a metal seal case 30 and a seal member 32 secured to the seal case 30, which is formed of an elastomer or other flexible material. A case 30 for mounting a sealing member 32 made of an elastomer has a cylindrical axial portion 34, and at one end of the cup 2, the counterbore 6 of the cap is attached.
An inset fit between the cylindrical surface of the counterbore 6 and the axial portion 34. As a result, the seal B
Is fixed in the correct position inside the cap 2. This interference fit establishes a static seal along the surface of the counterbore 6. In addition, the seal case 30 includes a radial portion 3 protruding inward in the radial direction from one end of the axial portion 34.
6, and an inclined portion 38 which projects toward the large-diameter end portion side of the tapered roller 16 at an angle with respect to the rotation axis x and projects inward.
The radial portion 36 and the inclined portion 38 are axially offset from the flange 26 of the shield C so as not to collide with the shield C. The radial portion 36 and the inclined portion 38 project in the direction of the axial portion 24 of the shield C, but between these and the axial portion 24 of the shield and the flange 26, a sealing member 32 made of an elastomer is housed. There is enough space for.

An elastomeric seal member 32 is secured to contact the inner edge of the ramp 38, the two faces immediately beyond this edge, and the minor portion of the radial section 36 (FIG. 2). . Since the seal member 32 projects from the installed position toward the axial portion 24 and the flange 26 and is located between the flange 26 and the curl 28, the relative axial displacements of the seal B and the shield C are prevented. It won't happen. However, the seal B and the shield C rotate relative to each other, and the seal member 32 has an effect of dynamically sealing the shield C.

More specifically, the seal member 32 is arranged along the shield C so as to form at least three shielding means.
The first of these is along the labyrinth 40, which faces the seal cavity 20 and adjoins the curl 28 and surrounds the axial portion 24 of the shield C and the axial portion. It is separated from the sealing surface 22 on the 24. The second shielding means constitutes a first dirt lip 42, which is provided axially away from the labyrinth 40 and directed inwardly towards the axial portion 24 of the shield C and of the flange 26. It is in contact with the sealing surface 22 in the vicinity. The third barrier forms the second dirt lip 44,
This is oriented outwards toward the flange 26 side, and similarly shield C
Is in contact with the sealing surface 22 of. The two dirt trips 42 and 44 are on the air side (outside) of the seal B and their main purpose is to remove foreign matter such as water, dirt, etc. from the sealed cavity 20. The first labyrinth 40 is on the lubricant side (inside) of the seal B, and its main purpose is to store the lubricant in the cavity 20.
It is to hold inside.

First, consider the labyrinth 40, which bends radially inward to provide a sealing surface on the axial portion 24 of the shield C.
It reaches the cylindrical surface 46 facing the part 22. The diameter of this cylindrical surface 46 is slightly larger than the sealing surface 22. As a result, the sealing surface 22
There is a small clearance c between the and surface 46. This clearance is, for example, in the range of 0.05 mm to 1.62 mm, which is an operating clearance against eccentricity that may occur between the labyrinth 40 and the seal surface 22 due to manufacturing error. One side surface of the cylindrical surface 46 is an inner end surface 48 facing the seal cavity 20, and the other side surface is an outer end surface 50 facing the dirt lip 42. The two end faces extend in the radial direction, that is to say in a plane perpendicular to the bearing axis x and are therefore parallel to one another. Neither the cylindrical surface 46 nor the inner end 48 is continuous, and there are small pockets or cavities 52 (FIGS. 2-4) in some places. This is because the lubricant that enters this portion is directed toward the tapered roller 16, that is, the seal cavity portion 20.
It is arranged to push it back toward. The cavities 52 are arranged at equal intervals on the circumference along the labyrinth 40, and the respective cavities 52 are open at the cylindrical surface 46 and the inner end surface 48 of the labyrinth 40, and the edges formed by these surfaces intersecting each other,
The hollow portions 52 are cut out at equal intervals. In order to carry out the action of returning the lubricant to the inside, each cavity 52 is provided with a pair of side faces 54 (third part 54) provided at an equal angle d with respect to the relative rotational direction k between the labyrinth 40 and the seal face 22. FIG. 4, FIG. 4). This angle d is 30
It should be in the range of ° to 60 °, preferably 45 °.

The two side surfaces 54 and the cylindrical surface 46 intersect with each other along the relative rotational direction k between the labyrinth 40 and the sealing surface 22, that is, a line inclined with respect to the circumferential direction.

Further, the cavity 52 is formed by providing an outward connection surface 56 between the two side surfaces 54. This surface is inclined in an angle with respect to the circumferential surface 46 and is farthest from the circumferential surface 46 at the inner end surface 48. The two side surfaces 54 may be flat, while the connecting surface 56 may be flat or slightly concave. These three surfaces 54 and 56 intersect the outer end surface 50, respectively, and the line of intersection between the outer end surface 50 and the two side surfaces 54 is located at a slight distance, and the line of intersection with the connecting surface 56 is a cylindrical surface 46. It is located outside in the radial direction. As a result, an opening for ventilation is formed on the outer end surface 50 toward the dirt lip 42, and this opening is located at the smaller end of the cavity 52.

As the cup 2 or cone 8 rotates, the lubricant between the sealing surface 22 on the axial portion 24 of the shield C and the cylindrical surface 46 of the first labyrinth 40 has an axial dimension along the side surface 54. Moves into the cavity 52 where Due to this relative rotation, the lubricant not only flows into the cavities 52, but also towards one side 54 of each cavity 52, which side 54 is relative to the direction of relative rotation k, ie the circumferential direction. It has an angle d and attempts to return the lubricant to the inside of the sealed cavity 20 and to the tapered rollers 16 inside this. The connection surface 56 is also inclined with respect to the axis X and likewise tries to return the lubricant to the closed cavity 20, and when the lubricant receives the centrifugal force generated by the relative rotation, the lubricant is closed. As it moves toward the hollow portion 20, it flows outward from the rotation axis x. Because the cavity 52 is wedge-shaped, it seeks to return the lubricant in only one axial direction, regardless of the relative rotational directions. Therefore, in one direction of rotation, the lubricant is in each cavity.
It is returned by one side 54 of 44 and the connecting surface 56 towards the closed cavity 20 inside the bearing A, and in rotation in the opposite direction it is connected with the other side 54. The surface 56 likewise seeks to return the lubricant axially back into the sealed cavity 22. The opening 58 at the end of the cavity 52, together with the clearance c between the cylindrical surface 46 and the sealing surface 22, prevents the labyrinth 40 from trapping air or lubricant inside the cavity 20 under high pressure. .

The first dart lip 42 (Figs. 2 and 4) is located away from the axial labyrinth 40 and the flange 26 of the shield C.
And a pair of side surfaces 62 that converge and intersect the sealing edge 64 near the flange 26.
It abuts the portion of the sealing surface 22 along the axial portion 24 of the.
In practice, the seal member 32 has a diameter of its sealing edge 64 which is less than that of the sealing surface 22 of the axial portion 24 so that the natural trip of the elastomer causes the dirt lip 42 to abut the sealing surface 22 along its edge 64. Is also shaped to be somewhat smaller. In addition, the outwardly facing surface of the dirt lip 42, i.e. the surface remote from the axis x, is provided with an outwardly opening groove 66 having an arcuate cross section located immediately behind the sealing edge 64, where A garter spring 68 is provided which causes the sealing edge 64 of the lip 42 to abut more strongly against the sealing surface 22. The garter spring 68 made of stainless steel has a small spring ratio and has an open spiral shape, that is, a spiral shape with a large distance.

The second dirt lip 44 (FIG. 2) is generally parallel to and slightly larger than the axis x with respect to the first dirt lip 42 and joins the radial portion 36 and the inclined portion 38 of the seal case 30. Protruding from the area. Free end of lip 44,
That is, the end portion far from the case 30 is bent outward in the radial direction and abuts on the portion of the seal surface 22 along the flange 26 of the shield C. The outwardly facing portion of lip 44 thus has two surfaces 70 which converge with each other to produce another sealing edge 72, which abuts sealing surface 22 at flange 26.
If the flange 26 were not present, the lip 44 would project axially beyond the sealing surface 22 of the flange 26. Thus, the flange 26 bends the lip 44 so that the natural bias of the elastomer maintains contact between the sealing edge 72 and the sealing surface 22 along the flange 26. The outwardly facing portion of the second lip 44 is formed as a slightly recessed surface 74 which allows water to flow to the central portion of the lip 44 rather than towards the sealing edge 72 and is removed. In this way, the shielding means against the invasion of moisture from the outside is formed.

The spaced apart first and second lips 42, 44 create a groove 80 (FIG. 2) in the seal member 32 that is axially deeply open toward the flange 26 of the shield C.
The groove 80 is filled with a grease-like lubricant that adheres to both the metallic sealing surface 22 and the smooth elastomeric surfaces of the two lips 42 and 44, forming a ring of lubricant. When the seal B and the shield C rotate relative to each other, the lubricant in the vicinity of the flange 26 of the shield C tends to remain attached to the seal surface 22, and remains attached to the two lips 42 and 44 of the seal member 32. It slides relative to the lubricant in the vicinity of the two lips 42,44 to be struck. When the seal B and the shield C actually rotate relative to each other, the lubricant is subjected to shearing force. The ring of lubricant r in the groove 80 substantially forms a shielding means between the seal member 32 and the sealing surface 22 to form a dynamic seal along the line of shear in the lubricant. It Between the edge 64 of the first dirt lip 42 and the outer end face of the labyrinth 40 is another groove 82 in the seal member 32, which groove 80.
Somewhat wider than, but not so deep. Above that groove
Reference numeral 82 is open inward in the radial direction and faces the portion of the sealing surface along the axial portion 24 of the shield C. This groove likewise has a ring of lubricant or grease s, which provides a shielding means between the sealing member 32 and the sealing surface 22.

The seal B is a portion of the curl 28 of the shield C in the axial direction.
Shield C by tilting in the axial direction as the connection part of 24
Mounted on top. The mandrel is preferably applied to the end of the curl 28 which is tilted in the axial direction, and the tapered surface of the mandrel is directed toward the end of the curl 28. The seal B is fitted along this tapered surface, the first dirt lip 42 of which is the axially collapsed curl 28 and the axial portion beyond it.
Expanded to 24 diameters. The expanded lip 42 moves over the curl 28 to a portion of the sealing surface 22 along the axial portion 24 of the shield C. Once the seal member 32 of the seal B is provided around the axial portion 24 of the shield C, the curl 28
Bends outwards into a normal position, which holds the seal B between the flange 26 and the curl 28 of the shield C. However, before the seal B is fitted into the shield C, the former axially open groove 80 is overfilled with lubricant. The groove 82 is likewise filled with grease.

The bearing A is assembled by inserting the cone assembly, i.e., the cone 8 with the rollers 16 held circumferentially by the retainer 18, into the cup 2 with a suitable grease-like lubricant. In practice, slightly more lubricant than required may be introduced into the annular cavity 20 of bearing A.
In any case, once the bearing A has been assembled, the seal B and the shield C are installed as a unit at the end of the bearing, forming a shielding means in contact with the end of the annular cavity 20. In particular, the axial portion 34 of the shield case 30 is the cup 2
Is pressed into the counter bore 6 and the axial portion 24 of the shield C is pressed into the cylindrical surface 14 on the thrust rib 12 of the cone 8. In order to press-fit the shield case 30 and the shield C, a punch having a recessed central portion is used. That is, the flange 26 of the shield C is applied to the recessed portion of the punch,
The radial portion 36 of the shield case 30 is applied to the peripheral portion thereof, and the shield C and the shield case 30 are press-fitted into predetermined positions by being pushed in by a punch. ,
The shield case 30 is fitted into the counter bore 6, and the shield C is fitted onto the cylindrical surface 14 of the rib 12. The offset face of the punch is such that shield B and shield C are in proper axial position relative to each other, and when so positioned, the sealing edge 72 of the second dirt lip 44 is the flange of shield C. It shall contact the sealing surface 22 along 26 and allow the lip 44 to be slightly deflected by the flange 26.

During operation of the bearing A, the cone 8 rotates relative to the cup 2 and vice versa. In either case, roller 16 is 2
Moving along the two raceways 4 and 10, we try to push the lubricant towards the larger diameter end of the annular cavity 20, ie towards the end where the seal B is located, which is the cone. This is a characteristic feature of the roller bearing during operation. Some of the grease-like lubricant acts on the axial portion of the sealing surface 22 and is trapped within the cavity 52 of the labyrinth 40. Cavity 52
The side wall 54 of the roller pushes the lubricant back toward the large diameter end surface of the roller 16.
This action occurs regardless of whether the cone 8 or the cup 2 is rotating, and regardless of which direction the relative rotation is.

Sealing edge of first lip 42 and outer surface 50 of labyrinth 40
The lubricant ring s in the shallow groove 82 between and serves as a barrier to the lubricant attempting to leak past the labyrinth 40 and to foreign matter trying to enter. The lubricant slightly exudes from underneath the sealing edge 64, resulting in a pressurized liquid elastic film between the edge 64 and the face 22. This membrane actually supports the first dirt lip 42 on the axial portion 24 of the sealing surface 22, which greatly reduces friction, minimizes wear on the lip 42, does not overheat, and is also fragile and fragile. Absent. groove
The ring r of lubricant in 80 is the sealing surface 22 along the flange 26.
To the radius of and adhere to it. The lubricant will remain attached to the flange 26 and the sealing surface 32,
When the rotation between the seal B and the shield C occurs, a slip line of the lubricant is generated in the lubricant ring r. The right side of the ring of lubricant acts as a shield along the sealing surface 22.
A small amount of lubricant leaches from the ring r along the sealing surface and lubricates the sealing edge 72 of the second lip 44 to reduce friction between it and the radial portion of the sealing surface 22. The centrifugal forces resulting from the relative rotation lubricate the sealing edge 72 and maintain it at that edge. Therefore, the wear of the second lip is likewise minimized, does not overheat, and is not brittle and fragile.

The labyrinth 40 primarily serves to retain the grease-like lubricant in the annular cavity 20, while the lubricant rings r, s in the dirt lip 42,44 and the two grooves 80,82 are
It mainly serves to remove foreign matter such as water, dust, and dust. Both lips 42,4 along their respective sealing edges 64 and 72
4 actually contacts the sealing surface 22 of the shield C, and in this sense is an effective barrier against the sealing surface 22. The function of these shielding means is to provide a lubricant ring r, s in the grooves 80 and 82.
It becomes more effective by the shielding means formed by. When the lubricant inside the groove 80 catches dust, the ring r more effectively blocks the entry of foreign matter. The dust easily attaches the lubricant to the flange 26 and the seal member 32, but does not significantly impair the smoothness of the lubricant along the deviation line.

Further, when the cup 2 rotates, the second lip 44 functions as a fringer that disperses foreign matter and moisture from the seal B. On the other hand, when the cone 8 rotates, the flange 26 of the shield C functions as a flinger. Second lip 44
Will be exposed to moisture and other foreign matter, but its upwardly-recessed concave surface 74 will serve as a channel that guides the moisture away from the seal line 72, allowing it to flow off the lip 44 without problems.

Some grease-like lubricant leaks out over time, but the two grooves 80, 82 remain filled with lubricant. In this regard, some of the lubricant filling cavity 20 travels along labyrinth 40 through labyrinth 40 to replace lubricant dissipated from groove 82. For the same reason, the groove 82 also dissipates lubricant through the sealing edge 64 of the lip 42, replacing the lubricant from groove 80. For that purpose the inner surface 62 and the sealing surface of the first lip 42
The angle between 22 is the outer surface 62 of the first lip and the sealing surface 22.
Less than the angle between. This allows the grease-like lubricant to easily move through the first lip 42, leaving the cavity 80 filled as long as there is lubricant in the cavity 82.

Increasing the air pressure inside the annular cavity 20 of bearing A facilitates this movement, but avoiding excessive air pressure. This is because the labyrinth is vented by the clearance c and its vent holes 58, and the lips 42, 44 are arranged so as to be lifted from the sealing surface when the pressure becomes excessive. The lubricant in the channels 80 and 82 is left untouched, and the lubricant is momentarily displaced to consider a passageway that vents excess atmospheric pressure.

Seal B and Shield C shown or described
Are provided at the ends of the double row bearing A, but they can also be provided in a single row tapered roller bearing. During operation, the cone is rotated to lock the cup or vice versa.

Regardless of whether the seal B is used for single-row or double-row bearings, this seal provides complete protection for bearings used as light or heavy truck wheel bearings. Therefore, it is not necessary to provide an auxiliary seal,
This reduces the cost of providing such a seal and the cost of providing a cut surface for such a seal. The seal B and the shield C are also useful for handling the bearing A. That is, the bearing A is supplied as a pre-assembled and pre-lubricated unit. Furthermore, this sealing surface 22, along which the seal B serves as a shield against the dissipation of lubricant and the ingress of foreign substances, is fitted during the manufacture of the seal and the bearing, so that the manufacturer of the part to which this bearing is attached is equipped with these surfaces. There is no need for control.

The modified seal D (Fig. 5) is very similar to the seal B and, like the seal B, cooperates with the shield C to form some shielding means against dissipation of lubricant and ingress of foreign matter. . However, the first dart lip 42 of the seal D is fitted with an insert 88 formed of a durable, flexible, low friction polymer such as polytetrafluoroethylene (PTFF).

A seal edge 64 is formed along the insert 88. Similarly, the second dirt lip 44 of the seal D is provided at a smaller angle to the radial portion of the sealing surface 22, thereby increasing the depth of the recessed surface 74 on the lip and comprising an elastomer. The seal member 32 is provided with a deep groove open to the outside.

Multiple rows of bearings E (Fig. 6) are adapted to support the rotating rolls of a mill stand for machining metal, which are bearings E.
It is closed by a deformed seal F, which is likewise fitted at the end of the, so that it is not necessary to provide a separate seal on the outside as is customary in the industry.

Bearing E has two double cones 90, each surrounded by an outer cup 92 and an inner cup 94, with a row of tapered rollers 96 between each cup 92 and 94 and the cone 90 surrounded thereby. There is. Unlike bearing A, bearing E
Has a large-diameter end surface of the tapered roller 96 at the end of the row facing away from the end of the bearing D and toward the center of the bearing E. The outer end of each double cone 90 is an enlarged rib 98 having an outwardly facing cylindrical surface 100. On the other hand, each outer cup 92 has a counterbore that extends axially outward.
It has 102 and surrounds it on rib 98 of cone 90. The seal F fits into the counterbore 102 at the end of the outer cup 92 where the cylindrical surface on the retaining rib 98 of the cone 8 is located.
Cooperates with Shield C fitted over 100.

Each seal F is essentially the same as the seal B, but is rather large and has a seal case 104 which is slightly different from the arrangement of the seal case 30 of the seal B. This is required to close the large space opposite the small diameter end face of the roller 96 in the endmost row. Similar to the seal case 30, the case 104 has an axial portion 34, a radial portion 36 and a beveled portion 38, arranged in that order towards the inside of the counterbore 102 of the cup. In addition, case 104 has another or inner radial portion 106, which faces radially inward from the end of beveled portion 38. Elastomeric seal member 32 is secured to another or inner radial portion 106, but also cooperates with shield C to provide multiple barriers along seal face 22.

The bearing E holds the seal F on its own, the protection of which depends solely on the seal F, or the seal F along the seal attached to the wheel stop, which is the seal arrangement in the application.
Depends on. The bearing E holds the seal F by itself, but it is not larger than the bearing of a conventional rotary roll without a seal, and thus can be immediately replaced with the conventional bearing.

The present invention is intended to include all modifications and improvements of the embodiments of the invention selected here for the purpose of disclosure, without departing from the spirit and scope of the present invention.

[Brief description of drawings]

FIG. 1 is a sectional view of a bearing to which a small-sized seal assembly constructed by embodying the present invention is attached, FIG. 2 is a partially enlarged sectional view of a part of the seal assembly, and FIG. 3 is FIG. 3 is a cross-sectional view of the seal assembly taken along line 3-3 to show the inner surface of the cavity of the seal, and FIG. 4 is a view taken along line 4-4 in FIG. 3 to show the lower surface of the seal member. 5 is a cross-sectional view of a modified seal assembly, and FIG. 6 is a partial cross-sectional view of a sealed rotating roll bearing modified to accommodate the seal assembly of the present invention. 2,92,94 …… Cup, 4,10 …… Raceway, 6,102 ……
Counterbore, 8 ... Cone, 12 ... Thrust rib, 1
4,46 …… Cylinder surface, 16,96 …… Tapered roller, 18 …… Cage, 20,52 …… Cavity, 22 …… Seal surface, 26 …… Flange, 30 …… Seal case, 32 …… Seal member, 38 …… Inclined part, 40 …… Labyrinth, 42,44 …… Der lip, 6
4,72 …… Seal edge, 80,82 …… Groove, 88 …… Insert,
A, E …… Bearing, B, D …… Seal, C …… Shield, F ……
Seal, c ... Clearance, x ... Rotating shaft.

Claims (3)

[Claims] 1. A first member (8) and a second member which rotate relative to each other.
A seal assembly comprising a combination of a seal and a sealing surface forming a shielding means for isolating a region defined between the sealing surface (22) and the member (2). A circumferential first sealing surface formed on the shield (C) fixed to the first member (8), and a second sealing surface extending radially outward from the first sealing surface. The seal (B) includes a rigid seal case (30) fixed to the second member (2) and a labyrinth (40) disposed on the first sealing surface. 40) is provided with an elastic seal element (32) fixed to the seal case at a portion provided with the labyrinth (40) and a circumferentially extending surface (46) facing the first sealing surface. A side surface (48) facing inwardly of the isolated region, the circumferential surface (46) being the first side surface. And a gap is formed between the labyrinth (40) and the first sealing surface, and a first dirt lip (42) extends toward and abuts against the first surface. Second
The first trip lip (42) extends between the labyrinth (40) and the second trip lip (44). A seal assembly characterized by being placed. 2. The dart lip (42,44) is configured such that the pressure acting on the side of the dart lip facing the isolated area causes each dart lip (42,44) to close the sealing surface (22). The labyrinth (40) is tilted toward the sealing surface so as to be spaced apart from the sealing surface, and the labyrinth (40) has a plurality of pumping cavities () open at the circumferentially extending surface (46) and the side surface (48). 52), each of the pumping cavities (52) has a wide width at the side surface (48) and a narrow width at a portion away from the side surface (48), and the labyrinth (40) and the sealing surface (52). 22) has a surface (56) inclined with respect to the relative rotation direction, and the lubricant that has entered the cavity (52) is discharged toward the isolated region by relative rotation. The seal assembly according to claim 1, wherein: 3. A groove (80) open toward the second surface, wherein the first and second second trips (42) and (4).
4. The grease is provided between the second surface and the groove, and the grease is provided in the groove (80) in contact with the second surface.
Or the seal assembly according to 2.