JPH0686907B2 - Small labyrinth type seal - Google Patents

Description

FIELD OF THE INVENTION The present invention relates generally to seals, and more particularly to a seal that is very compact but effectively retains a lubricant therein and prevents foreign matter from entering the bearing.

2. Description of the Related Art The steering knuckle of a front-wheel drive automobile has a bearing for rotating the front wheel, and each bearing is practically housed in the steering knuckle, and Wheels support a rotatable bolted bolt. This mechanism has a very small space for accommodating the bearing, and therefore the bearing of the front-wheel drive vehicle is very compact. As a matter of course, such a bearing needs to hold a lubricant and be hermetically sealed in order to remove foreign matters, and has a sufficient spread, that is, a sufficient space between two rows of rolling elements in the bearing. The space occupied by the seals should be as small as possible to ensure space. Typically, the seal fits over the end of the bearing and is unitized to facilitate handling of the bearing.

In some cases a second seal is provided between the knuckle and the hub, especially outside the main seal at the inner end of the bearing, to provide extra protection, but this second seal does not provide an effective barrier. If so, it only leads to a loss of bearing life. For example, if the second seal is of poor quality or damaged, or if it is provided around a poor quality contact surface, foreign matter, such as water, may enter the space between the second seal and the main seal. It invades and accumulates in this part. These foreign substances will eventually degrade the main seal and the bearings intended to be protected by this main seal. That is, the ineffective second
Seals give worse results than no.

Aside from the potentially harmful effects of the second seal, the second seal forms part of an already complicated assembly, and the second seal is attached to it and pressed at the contact surface. A cutting finish surface that touches is required. This naturally increases the manufacturing cost of the front-wheel drive vehicle.

Means and Actions for Solving the Problems A typical bearing for a front wheel in a front-wheel drive vehicle is supplied as a unit and includes a single outer race, and has bearing seals at both ends thereof. The seal of is pressed against the inner race. The seal according to the present invention becomes a very effective seal when it is arranged at both ends of the bearing for a front-wheel drive vehicle, and it becomes unnecessary to provide the second seal. Furthermore, the load is very small and almost no extra torque is required. This seal not only prevents the leakage of the lubricant in the bearing, but also acts to return the lubricant inside the bearing.

Embodiments Embodiments of the present invention will be described below with reference to the drawings. The same reference numerals in the drawings denote the same parts.
As shown in FIG. 1, a tapered roller bearing A consisting of two rows has a seal B at each end thereof and a shield C cooperating therewith.
The seal B and the shield C are both disposed at the ends of the bearing A and are held together as parts of the bearing A so that the parts of the bearing A do not have to be handled separately. Contributes to unity. Bearing A is very compact and has the large carrying capacity and durability characteristic of tapered roller bearings, which makes it suitable for use in the front wheels of front-wheel drive vehicles.

The bearing A includes a double cup 2, which has a pair of inward facing raceways 4 and a cylindrical counterbore 6 at the large diameter end of the raceway 4 leading to the end of the cup 2. (Fig. 1). Between the both ends of the cup 2, the cup 2 is clamped and fixed to a support structure such as a handle knuckle of a suspension mechanism of an automobile. This cup 2
Surrounds a pair of cones 8 which meet each other at the center between the ends of the cup 2 or at the smallest radius of the raceway 4 of the cup. Each cone 8 has a raceway 10 of varying radius, which is opposed to and is surrounded by the raceway 4 of the cup. Each cone raceway 10 leads to a thrust rib 12 having a larger radius outwardly facing cylindrical surface 14 which connects to the end of the cone 8 known as the cone back surface. The thrust rib 12 forms part of the cone 8, the cylindrical surface 14 of which lies inside the counterbore 6 at the corresponding end of the cup 2. The two cones 8 are both clamped to another structure, for example a hub in the knuckle of a front wheel drive vehicle.

In addition to the double cup 2 and the two cones 8, the bearing A includes tapered rollers 16 arranged in two rows corresponding to two sets of opposing raceways 4 and 10 on the cup 2 and the cone 8.
(FIG. 1). That is, each row of rollers 16 surrounds each cone 8. The roller 16 has its large-diameter end face in contact with the thrust rib 12 of each cone 8, and the roller 16 rolls out from the space between the raceways 4 and 10 when a radial load is applied to this thrust rib. Is preventing things. Each row of rollers 16 has adjacent rollers
A retainer 18 is provided to keep the 16 properly spaced, which further retains the roller 16 about the cone 8 when the cone 8 is removed from the cup 2. Each cage 18 has a large-diameter end ring on the large-diameter end face of the roller 16 and towards the counterbore 6 at the corresponding end of the cup 2, more precisely the thrust bores of the counterbore 6 and the cone 8. It projects toward the annular space between the upper and the cylindrical sealing surface 14 above. The tapered rollers 16 and the cage 18 of the rollers 16 arranged are
A seal B and a shield C move in an annular cavity 22 whose ends are closed and sealed or separated.

The cup 2 and the cone 8 are provided with the rotation axis X of the bearing A as the same center, and when used as a typical front wheel drive vehicle bearing, the cup 2 is fixed and the cone 8 rotates in the cup 2. Thus, the two rows of tapered rollers 16 move along the raceways 4 and 10 and also have an annular cavity to reduce the friction between the large diameter end faces of the rollers 16 and the thrust ribs 12 of the two cones 8. A grease-like lubricant is supplied to the inside of the portion 22. Tapered roller 16 attempts to return this lubricant to thrust 12. Generally, the seal B and the shield C are provided in an annular space between the counterbore 6 of the cup and the cylindrical surface of the thrust rib 12 to prevent the leakage of the lubricant. Furthermore, the seal B, together with the shield C, prevents dust, water, and other foreign matter from entering the inside of the bearing. Thus, the seal B and the shield C serve to separate the annular cavity 22 (FIG. 1) existing between the cup 2 and the two cones 8 from the outside.

Since the hollow portion 22 includes the tapered rollers 16, it is subjected to a wide temperature change. However, since the seal B vents the cavity 22 to the outside, this temperature change does not seriously affect the air pressure inside the cavity 22.

First, consider the shield C. This is cone 8
A sealing surface 24 fitted over the upper thrust rib 12 and establishing shielding with the seal B at the end of the annular cavity 22.
give. For this purpose, each shield C merely constitutes a metallic stamping consisting of an axial mounting portion 26 and a flange 28 projecting radially from the end of the axial portion 26. The sealing surface 24 of the shield C is along the axial portion 26 and the flange 28 (Fig. 2). The axial portion 26 is press fitted onto the thrust rib 12 of the cone 8,
An interference fit is provided between this and the surface 14 of the thrust rib 12. The flange 28 is flush or slightly inboard with the back surface of the cone 8 and within the counterbore 6 of the cup 2, but does not project radially enough to contact the cup 2.

Each seal B (FIG. 2) includes a metal seal case 30 and a seal member 32 fixed to the seal case 30 and made of an elastomer. A case 30 for mounting a sealing member 32 made of an elastomer has a cylindrical axial portion 34, which is fitted into the counterbore 6 of the cup at one end of the bearing A and has a cylindrical surface and an axial portion of the counterbore 6. 34 and interference fit. This secures the seal B in the correct position inside the cup 2.
This interference fit also establishes a static seal along the surface of the counterbore 6. In addition, the seal case 30 is integrally formed with the axial portion 34, and has a radial portion 36 protruding inward in the radial direction from one end of the axial portion 34, which is a flange of the shield C so as not to collide with the shield C. 28
Axially offset with respect to. In fact, the radial part
36 projects toward the axial portion 26 of the shield C, but between the radial portion 36 and the axial portion 26 and the radial portion 28 of the shield C, a sealing member 32 made of an elastomer is housed. There is enough space for.

The sealing member 32 of elastomer is sealed along the inner edge of the radial portion 36 and beyond the edge as well as along the two faces of the radial portion 36.
Is stuck to. This seal member is the surface 24 of the shield C.
This seal member 32 is used to provide an operational seal against
From the installed position towards the axial portion 26 and the radial portion 28 of the shield C, but also towards the closed cavity 22. Inside the cavity 22 thus sealed is provided an annular space through which the large-diameter end ring at the end of the retainer 18 projects, which ring naturally follows the cone 8
Rotates in this space when rotates in the cup 2 and vice versa.

More specifically, the sealing member 32 is arranged along the sealing surface 24 of the shield C so as to provide three shields. The first shield is provided along a first labyrinth seal (hereinafter, simply referred to as labyrinth) 40 that is exposed toward the closed cavity 22 (FIG. 2). It surrounds the axial portion 26 of the shield C, but is spaced from the sealing surface 24 of this axial portion 26. The second shield is in a direction tilted from the labyrinth 40 and is a dirt lip that actually contacts the sealing surface 24 along the axial portion 26 of the shield C.
Make up 42. The third shield is the flange 28 of shield C.
It forms a second labyrinth which faces and is spaced from the upper sealing surface 24 portion. Second
The labyrinth 44 and the dart rib 42 are on the outside of the seal B (on the air side) and their main purpose is to prevent foreign objects such as water, dust, and dust from entering the sealed cavity 22. The first labyrinth 40 is inside the seal B (the side with the lubricant), and its main purpose is to retain the lubricant inside the cavity 22.

First, consider the first labyrinth 40 (second to fourth)
Figure). It bends radially inward and extends to the outer peripheral surface 46 of the cylinder. This outer peripheral surface 46 is the axial portion of the shield C.
It faces the cylindrical sealing surface 24 on 26 and is slightly larger in diameter than this. This results in seal faces 24 and 56
There is a slight gap c between the and. This clearance is typically in the range of 0.05 mm to 1.62 mm, which is a clearance at the time of operation because there may be an eccentricity between the labyrinth 40 and the seal surface 24 due to a manufacturing error. One side of the cylindrical surface 46 has an inner end surface 48 facing the closed cavity 22.
And the other side is the outer end face facing the second lip 42.
Fifty. Both end faces are in the radial direction, that is, in mutually parallel planes orthogonal to the bearing axis X.

The cylindrical surface 46 and the inner end surface 48 are not continuously formed, but a small pocket or cavity 52 is provided between them. It is shaped so as to return the lubricant contained therein to the direction of the tapered rollers 16, that is, to the inside of the closed cavity 22. The cavities 52 are provided at equal intervals along the outer periphery of the first labyrinth 40, face both the cylindrical surface 46 and the inner end surface 48, and block the sides where both surfaces intersect at certain places. . Each cavity 52 is provided with a labyrinth 40 and a sealing surface 24 to perform the action of returning the lubricant to the inside.
It has a pair of side faces 54 (FIGS. 3 and 4) provided so as to form an equal angle d with respect to the relative rotation direction k between them. This angle d should be in the range 30 ° to 60 °, preferably 45 °.

The two side surfaces 54 and the cylindrical surface 46 define the first labyrinth 40.
And the sealing surface 24 intersect with each other along the relative rotational direction k, that is, a line inclined with respect to the circumferential direction. Two more sides 46
The cavity 52 is formed by providing the connection surface 56 to the outside between them. This surface is oriented in a direction inclined with respect to the cylindrical sealing surface 24, and is most distant from the cylindrical sealing surface 24 at the inner end surface 48. The two side surfaces 54 are flat,
On the other hand, the connection surface 56 may be a flat surface or a slightly concave concave surface. 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.
It is located radially outside of 46. 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 cone 8 rotates, the lubricant between the sealing surface 24 on the axial portion 26 of the shield C and the cylindrical surface 46 of the first labyrinth 40 changes axially along the side surface 54. Move into the cavity 52. The rotation of the cone 8 not only causes the lubricant to flow into the cavities 52, but also the respective cavities.
Flowing towards one side 54 of the 52, this side 54 has an angle d relative to the direction of relative rotation k, i.e. the circumferential direction, inside the lubricant-filled cavity 22 and inside this cone. I'm trying to get it back to around 16. Since the connection surface 56 is also inclined with respect to the axis X, the cavity 22 in which the lubricant is similarly sealed
When the lubricant is subjected to centrifugal force generated by the relative rotation between the cup 2 and the cone 8, the lubricant moves outward from the rotation axis X as the lubricant moves toward the closed cavity 22. Flows toward. Because the cavity 52 has a wedge shape, the lubricant is applied to one side of the shaft regardless of the direction of rotation of the cone 8 and which of the cone 8 and the cup 2 is the rotating race of the bearing A. I try to return only to the direction of. Therefore, when rotating in a certain direction, the lubricant will not contact the side surface 54 of one of the cavities 52 and the connecting surface.
By means of 56 and 56, it is returned towards the closed cavity 22 inside the bearing A, and in the opposite rotation, the other side surface 54 and the connecting surface 56 likewise carry the lubricant axially. Attempting to return to the closed cavity 22 along. Cylindrical surface 46
A ventilation opening 58 provided at the end of the cavity 52 along the gap between the shield and the axial portion 26 of the shield C prevents the air pressure in the sealed cavity from rising.

The dirt lip 42 (FIG. 2) projects outwardly of the bearing away from the first labyrinth 40 and has side surfaces parallel to each other, a short end surface and a contact surface 64. The inner sides of the two side faces are connected to the outer end face 50 of the first labyrinth 40 at its edge portion, thereby forming a narrow annular space 66 between the labyrinth 40 and the dirt lip 42.
The contact surface 64 of the dirt lip 42 when it is not bent
Has a diameter somewhat smaller than the cylindrical surface 46 and the sealing surface 24 on the axial portion 26 of the shield C, and when the seal B is mounted on the bearing A, the dart lip 42 has its contact surface 64 in the axial direction. It is pressed against the sealing surface 24 on the portion 26 and bent slightly outward. Thus, in contrast to the first labyrinth 40, there is some friction between the dirt lip 42 and the sealing surface 24. However, this friction is small due to the small contact area and the fact that a small amount of lubricant seeps through the first labyrinth 40 into the contact portion of the contact surface 64, especially when the bearing is stationary.

The second labyrinth 44 has two ribs 68 (FIG. 2,
(Fig. 5), which projects axially toward the flange 28 of the shield C but does not contact the sealing surface of the flange 28. Each rib 68 has a columnar shape with the axis X as a common axis.
Two ribs 68 with one side and a cut-away end face 70
The two end faces 70 of are in the same plane orthogonal to the axis X. End face
70 is separated from the sealing surface 24 of the flange 28, and another gap e is formed between them. This clearance e should be in the range between about 0.13 mm and 0.66 mm. The two ribs 68 provided apart from each other add two grooves to the seal member 32 made of elastomer. One is the groove 74 between the dirt lip 42 and the inside of the two ribs 68,
The other is a groove 76 between the two ribs 68. Groove 74 is V
It has a V-shaped cross section, while the groove 76 has a rectangular cross section.

The bearing A is provided as a unit ready for immediate installation in a steering knuckle or other device of a vehicle and supplies the enclosed cavity 22 and the seal B and shield C where they should be with a lubricant. In fact, the seal B and the shield C help to make the bearing A easy to integrate in that it prevents the roller 16 and the cone 8 from moving axially outward from the end of the integral double cup 2. The bearing A is simply assembled by two cone-shaped assemblies, namely by inserting the cone 8 together with the rollers 16 and the retainer 18 from both ends of the cup 2 until the front faces of the two cones 18 meet at the center of the cup 2. Prior to this, a suitable grease-like lubricant is applied to the inside of the cup 2 and the two conical assemblies. With the cone 8 installed in this manner, the rollers 16 are disposed inward from the cups 2 and the raceways 4 and 10 of the cone 8. The seal B and the shield C are installed as a unit from the end of the bearing A. More specifically, each of the seal B and the shield C is a bearing A.
It is assembled so as to have a relative positional relationship expected in the inside.
That is, the dirt lip 42 of the seal B is widened to have a diameter sufficient to fit around the axial portion 26 of the shield C, and the seals B and shield C are effectively arranged such that the former dirt lip 42 is effectively the latter axial direction. The sealing surfaces 24 located along the portion 26 are moved relative to each other so as to partially enclose them. In order to expand the dirt lip 42, it is moved on the tapered mandrel and guided to the axial portion 26 of the shield C. The seal B and the shield C thus combined are pressed together into the end of the bearing B. That is, the axial portion 34 of the seal case 30 is pushed into the counter bore 6 at one end of the cup 2,
At the same time, the axial portion 26 of the shield C is pushed onto the thrust rib 12 of the cone 8 inside the counterbore 6. The force applied during this installation is provided through a punch that is placed against the radial portion 36 of the seal case 30 of seal B and the flange 28 of shield C. The axial displacement of the surface of the punch pressed against the seal case 30 and the shield C causes the seal B and the shield C to axially move the end face 70 on the rib 68 of the second labyrinth 44 and the flange 28 of the shield C. The distance is set so that the upper sealing surface 24 has an appropriate distance.

When the bearing B is activated, the cone 8 rotates relative to the cup 2 or vice versa. As a result, the tapered rollers 16 return some of the lubricant in the direction of the thrust ribs 12 of the two cones 8 and onto the sealing surface 24 on the axial portion 26 of the shield C provided on this thrust rib 12. Try to. This lubricant hits the first labyrinth 40 of each seal B, and if not too much, most of it is returned towards the tapered rollers 16 and the cavity 22 in which they rotate. In particular, when moving along the sealing surface 24 on the axial portion 26 of the shield C of the cone 8, the lubricant is trapped in the cavity 52 of the first labyrinth 40 of the seal B at the end of the bearing A. Where the side surfaces 54, which are inclined with respect to the relative rotational direction between the sealing surface 24 and the first labyrinth 40, attempt to return the lubricant towards the axially and radially sealed cavity 22. To do. The connection surface 56, which was inclined with respect to the axis X, likewise returns the lubricant in the axial direction. When the cone 8 constitutes the rotating race of the bearing B, the centrifugal force generated tends to disperse the lubricant into the outer cavity 52. However, even when the cup 2 is the rotating portion, the surface tension between the cylindrical surface 46 of the first labyrinth 40 and the lubricant is sufficient to supplement the lubricant in the cavity 52. And are returned axially and radially by the faces 54 and 56 of the cavity 52.

A very small amount of lubricant reaches the contact surface 64 with the dirt lip 42 either under the cylindrical surface 46 of the first labyrinth 40 or through a ventilation opening 58 in this labyrinth, which surface To reduce friction between the sealing surface 24 on the axial portion 26 of the shield C. The dirt lip 42 primarily prevents dirt, moisture, and other foreign matter from entering the interior of the sealed cavity 22 and prevents the raceways 4, 10 and the rollers 16 within the cavity from being damaged by the foreign matter. In addition to this, when the lubricant enters the lower region of the cylindrical surface 46 of the first labyrinth 40, the dirt lip 42 creates rearward pressure. This rearward pressure minimizes the amount of lubricant that can enter from this area and forces some lubricant towards the cavity 52, resulting in a sealed cavity. Return lubricant to 22. At the start and stop of operation or when the rotational speed is low and the cavity 52 cannot effectively return lubricant into the enclosed cavity 22, the annular space 66 adjacent to the dirt lip 42 is particularly filled with lubricant. , This is the contact surface of the dirt lip 42 when the rotation speed increases
Supplied to 64.

The grease-like lubricant is the two grooves 74 of the second labyrinth 44.
And also between 76 and 76, the lubricant here expands the space between the second labyrinth 44 and the part of the sealing surface 24 along the flange 28 and adheres better to the latter than to the former. Therefore, when the shield C rotates relative to the seal B, or vice versa, the lubricant tries to leave behind a portion of the flange 28 of the shield C on the second labyrinth of the seal B.
Glide over the smooth surface above 44. This lubricant acts as a barrier g for the passage of foreign matter along the sealing surface 28 and in fact prevents many foreign matter from reaching the dirt lip 42 which is a more effective obstacle. Foreign matter, especially dust, mixes with the lubricant along the second labyrinth 44, which effectively causes the lubricant to adhere to the flange 28 of the shield C, but substantially on the circumference of the labyrinth 44. It does not reduce the slipperiness of the.

A grease-like lubricant that enhances the effect of the barrier g on the foreign matter along the second labyrinth 44 is applied to the seal B and the shield C.
It may be applied to the labyrinth before fitting on top. On the other hand, it is also obtained from the inside of the annular cavity 22. For this reason, if excessive lubricant is added to the bearing A during assembly, the tapered roller 16 at the initial operation of the bearing A will pass through the first labyrinth 40 and the sealing surface 24 in spite of the cavity 52. Apply some force to some of the lubricant and enough force to lift and separate the seal face 24 against the dirt lip 42 to remove excess lubricant from the second labyrinth 44 and the flange 28 of the shield C. Push into the space between. This excess lubricant fills the grooves 74,76 and allows the second labyrinth 4
The space between 4 and the portion of the sealing surface 24 on the flange 28 is widened to form a barrier g.

When the air pressure inside the closed cavity 22 rises during normal operation of the bearing A, this rise in air pressure is transmitted to the annular space 66 between the labyrinth 40 and the dirt lip 42 through the gap c and the ventilation opening 58. However, if this increase in air pressure is large enough, slightly raise the tar trip 42 to reduce this air pressure. The air released in this way is the second labyrinth.
At 44, the lubricant is displaced to some extent and communicates with the outside, but this lubricant immediately returns to its original position, and the grease barrier g is formed again at the second labyrinth 44. Therefore, the air pressure inside the closed cavity 22 does not become so great as to damage or move the seal B.

The seal B is most suitable for the one installed in a configuration in which the cup 2 is stationary and the cone 8 is rotated. This is because the rotation of the cone 8 also rotates the shield C, and this flange 28 serves to scatter foreign matter from the elastic seal member 32 to the outside. Another deformed seal D (FIG. 6) fits better into the bearing A when the cup 2 is rotated and the cone 8 is stationary. The deformed seal D likewise cooperates with the shield C to isolate the annular cavity 22 in the bearing A and is virtually equivalent to the seal B except for the presence of the flinger 80.

The flinger 80 is integrally formed with the seal member 32 made of an elastomer and is a part of the seal member 32. This is described in the axial direction from the radial portion 2 of the seal case 30 and surrounds the outer edge of the flange 28 of the shield C but does not contact the shield C. In effect, the flinger 80 is somewhat tilted with respect to the flange 28, the outer free end of which is farther from the axis of rotation X than the inner fixed end. Therefore, when the bearing B stands still and water falls on the front side surface of the fringer 80, it flows toward the flange 28 and drops from the fringer 80. Thus fringer 80
Keeps water away from the second labyrinth 44. On the other hand, when the cup 2 rotates while the bearing B is operating, the fringer 80 also rotates accordingly, and the foreign matter that has reached the fringer 80 is scattered outward from the fringer 80 and the second labyrinth 44 inside by the centrifugal force generated. To be done.

Another seal E (Fig. 7) is equivalent to seal B, but it does not act as a barrier along shield C, but instead along the cut surface leading out from annular cavity 22 to the outside. Become a barrier. Therefore, the lubricant is made to move along the surface of the cylindrical surface 14 of the thrust rib 12 on the cone 8. The first labyrinth 40 surrounds the surface 14 and a cavity 52 within the enclosure 40 returns the lubricant to the cavity 22.
In addition, the dirt lip 42 contacts the surface 14 and provides a barrier to foreign objects attempting to pass through this surface.

The rear surface of the cone 8, that is, the radial surface of the end of the thrust rib 12 is in contact with the cut surface or shoulder 82 fixed at a proper position with respect to the cone 8. shoulder
82 extends radially outwardly beyond the second labyrinth 44, the surface of which is spaced from the end faces of the two ribs 68, and the seal B
A gap e equivalent to the gap e is formed between the end face 70 and the shoulder 82.

Therefore, the cylindrical surface 14 of the cone thrust rib 12 along with the seal E serves the same purpose as the sealing surface 24 on the axial portion 26 of the shield C, and the shoulder 82 is similar to the sealing surface portion on the flange 28 of the shield C. Act on.

The seal member 32 provided on the seal B, D or E can be molded from a flexible polymer or the like instead of using an elastomer. Further first and second labyrinths
40 and 44 are molded of metal or other rigid material to which the dart lip 42 is secured. In this case, the dirt lip 42 is molded from an elastomer or polymer and has flexibility.

As the seals B, D and E, the first labyrinth 40
Instead of providing a cavity 52 consisting of two side faces 54 and one connecting face 56 inside, the labyrinth has a cylindrical face 46.
It is also possible to provide a cavity 90 (FIGS. 8 and 9) consisting of two side surfaces 92 which intersect with each other and are inclined with respect to this, and also inclined with respect to the inner end surface 48 and intersect each other.
In this way, in each cavity 90 the two sides 92 intersect at a line 94 inclined to the axis of rotation, giving the cavity 90 a generally wedge-shaped cross-section. The lubricant entering the cavity 90 acts to move axially and radially from the first labyrinth 40 and is returned to the annular cavity 22.

If the seals B, D and E are provided at the end of the bearing A, they will be mounted in a housing containing the bearing A therein, and these need not be used together with a bearing having an anti-friction action. Absent.

The present invention is intended to include all modifications and alterations of the specific examples 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 partial cross-sectional view showing a bearing having a seal and a shield cooperating with the seal, which is an embodiment of the present invention, and FIG. 2 is a seal constituting the present invention, a shield cooperating with the seal, and this bearing. Enlarged cross-sectional view of the surrounding area.
A partial side view of the seal and shield taken along the line 3-3 in the figure, and FIG. 4 is the bottom of the first labyrinth taken along the line 4-4 in FIG. 3, that is, on the shield. Showing the surface opposite to the sealing surface of Fig. 5, Fig. 5 is a partial view of the seal end portion taken along the line 5-5 in Fig. 2, and Fig. 6 is a view showing the area surrounding the bearing. FIG. 7 is an enlarged sectional view showing a deformed shield and a shield cooperating therewith, FIG.
The figure shows an enlarged cross-sectional view of the seal with its periphery deformed so that the seal is not necessary, and Fig. 8 is the first labyrinth and the deformed cavity cut along the line 8-8 in Fig. 7. Fig. 9 is a side view showing Fig. 9 and Fig. 9 is a diagram showing a deformed first labyrinth taken along the line 9-9 in Fig. 8. 2 …… Cup, 8 …… Cone, 12 …… Thrust rib, 16
…… Tapered roller, 18 …… cage, 28 …… flange, 30…
… Seal case, 32 …… Seal member, 40 …… First labyrinth, 42 …… Der lip, 44 …… Second labyrinth, 52,90 …… Cavity, 54 …… Side, 56 …… Connecting surface , 58
...... Opening, 68 ...... Rib, 76 ...... Groove, 80 ...... Fringer, 82 ...... Shoulder, A ...... Bearing, B ...... Seal, C
……shield.

Claims (2)

[Claims] 1. A first member (8) and a second member which rotate relative to each other.
A sealing surface forming a shielding means for isolating an area (22) defined between the sealing surface (24) and the member (2). From the first sealing surface, which is formed on the shield (C) fixed to the member (8) and has a circumferential shape, and a second sealing surface that extends radially outward from the first sealing surface. The seal (B) includes a rigid seal case (30) fixed to the second member (2) and an elastic seal element (32) fixed to the seal case. (32) is separated from the first labyrinth (40) arranged around the first seal surface from a side far from the region (22) of the first labyrinth, and is provided on the first seal surface. A flexible dart lip (42) to abut,
The second sealing surface has a surface (70) separated from the second sealing surface.
Second labyrinth (44) in which a gap is formed between the surface (70) of the labyrinth (44) and the second sealing surface.
The labyrinth (40) has a circumferentially extending surface (46) facing the first sealing surface, and a side surface (48) facing the inside of the region (22), The circumferentially extending surface (46) is spaced from the first sealing surface to form a gap between the first labyrinth (40) and the first sealing surface, and the dirt lip (42). Is disposed between the first labyrinth and the second labyrinth. A seal and sealing surface combination. 2. The second labyrinth (44) has a pair of axially extending ribs (68), and a groove (76) is formed between the ribs (68). The combination of the seal and the sealing surface according to claim 1.