JP2009024808A - Sealing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealing device capable of remarkably reducing the torque and preventing the sealing device from coming loose. <P>SOLUTION: A projection part 70 is formed in the outer peripheral surface of a fixing part 65 fixed to an inner ring of a slinger 52, extending circumferentially and projecting radially outward. In a non-worn state during usage with an elastic member 51 assembled in the slinger 52, a second axial lip 55 positioned in the axial innermost in the lip is positioned at an interval with respect to the fixing part 65 of the slinger 52. The axial lip 55 has a bent part 72, and the tip of the bent part 72 is positioned in the innermost in the second axial lip 55. While the bent part 72 is positioned between the projection part 70 and a flange part 66 of the slinger 52 in the axial direction and an elastic member 51 is not used after assembly into the slinger 52, the bent part 72 has a part overlapping the projection part 70 in the axial direction. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sealing device.

  Conventionally, as a sealing device, there is one described in Japanese Utility Model Publication No. 4-93571 (Patent Document 1).

  This sealing device is disposed between the inner race and the outer race of the hub unit. The sealing device includes a metal core member, an elastic member fixed to the metal core member, a slinger having an L-shaped cross section, and a garter spring. The slinger includes an axially extending portion and a radially extending portion, and the elastic member slides on the radial lip that always slides on the axially extending portion and on the radially extending portion. A first axial lip; and a second axial lip that is positioned radially inward of the first axial lip and slides on the radially extending portion. The second axial has an annular groove on the outer surface in the radial direction.

  The garter spring is fitted into the annular groove of the second axial lip. The garter spring plays a role of pressing the second axial lip inward in the radial direction.

In such a background, in the hub unit, it is desired to significantly reduce the torque of the sealing device that seals the rolling elements to the outside. Conventionally, when the sealing device is transported or when the sealing device is assembled, the slinger, the elastic member, and the metal core member may be separated, and the sealing device may be scattered. For this reason, it is desired to prevent the sealing device from being scattered.
Japanese Utility Model Publication No. 4-93571 (FIG. 1)

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a sealing device that can significantly reduce torque and that does not generate any fluctuations.

In order to solve the above problems, the sealing device of the present invention is:
A cored bar member having a cylindrical fixing part and a radially extending part extending from the fixing part in a substantially radial direction of the fixing part;
An elastic member fixed to the cored bar member;
A slinger having a cylindrical fixing portion having a protruding portion on the outer periphery and a flange portion extending substantially in the radial direction from the fixing portion,
The elastic member is
A base fixed to the radially extending portion of the core member;
A first axial lip extending from the base and sliding on the flange;
A second axial lip that is positioned between the first axial lip and the fixed portion of the slinger and slides on the flange;
The second axial lip is connected to the first portion extending from the base in a direction approaching the fixing portion of the slinger, and is connected to the first portion via a bent portion, and is connected to the fixing portion of the slinger. A second portion that extends in a direction away from the flange portion and slides on the flange portion, while the elastic member is incorporated into the slinger and is in a non-wearing state during use after installation. Located at a distance from the fixed part,
When the bent portion is positioned between the projecting portion and the flange portion of the slinger in the axial direction, the elastic member is not used after being installed after being installed in the slinger. The bent portion has a portion that overlaps the protruding portion of the fixed portion of the slinger in the axial direction.

  The non-wearing state at the time of use is a state in which the axial preload between the slinger and the sealing member (consisting of a metal core member and an elastic member) operates the sealing device, and when the sealing device is used. This means a state where the lip is a predetermined value in a non-wearing state. Further, when not in use after the assembly, the slinger is assembled with a seal member (consisting of a core metal member and an elastic member), and the axial preload between the slinger and the seal member is equal to the predetermined value. It means a smaller state.

  The inventor is a so-called pack-sealing type sealing device having a cored bar member, an elastic member, and a slinger having an L-shaped cross section, which has two radial lips and one axial lip. The magnitude of the torque caused by the lip contact load was investigated. As a result, the ratio of the torque due to the contact load of the two radial lips reached about 80%, and it was found that most of the torque was due to the contact load of the radial seal.

  According to the present invention, the second axial lip is positioned in the radial direction with respect to the fixed portion of the slinger in a non-wearing state during use after the elastic member is incorporated into the slinger. In addition, since there is no radial lip, the torque can be drastically reduced in the non-wearing state, and the fuel consumption of an automobile or the like having this sealing device can be reduced.

  Further, in the present invention, compared to the configuration in which a radial contact lip is present, in the initial state of non-wear, there is no radial contact lip, so the torque can be significantly reduced, while the radial contact lip The frictional force in the axial direction due to the absence of the elastic member disappears, and the elastic member and the metal core member may easily move in the axial direction with respect to the slinger.

  However, according to the present invention, the bent portion is positioned between the protruding portion and the flange portion of the slinger in the axial direction, and when the bent portion is not used after being assembled. Since the portion has a portion that overlaps the protruding portion in the axial direction, even if the elastic member and the cored bar member move in the axial direction with respect to the slinger, the protruding portion causes the bending. The axial movement of the portion is hindered, the axial position of the bent portion is limited between the protruding portion and the flange portion, and the elastic member and the metal core member are axially endless with respect to the slinger. Never move on. Therefore, the slinger, the elastic member, and the cored bar member are not separated.

In one embodiment of the sealing device,
The protruding portion is annular and extends in the circumferential direction of the fixed portion of the slinger,
In a state after the elastic member is incorporated in the slinger, and in a state where the pressing force of the second axial lip against the flange portion is reduced by a predetermined force or more due to wear of the second axial lip, the bent portion is And slides on the fixed part of the slinger.

  According to the embodiment, since the fixing portion of the slinger has an annular protrusion protruding toward the second axial lip, the protruding portion of the fixing portion of the slinger, the second axial lip, Thus, a labyrinth seal can be formed, and the sealing performance of the sealing device can be improved.

  Further, according to the above-described embodiment, the bending portion is fixed to the slinger fixing portion in a state where the pressing force with respect to the flange portion of the second axial lip is reduced by a predetermined force or more due to wear of the second portion of the second axial lip. Since it comes into contact and slides on the fixed part, even if the wear of the second axial lip is accelerated, foreign matter such as muddy water from the outside at the bent part as the radial lip is transferred to the hub unit. It is possible to suppress entry into the moving object arrangement space.

In one embodiment of the sealing device,
In a state before the elastic member is incorporated in the slinger, the radially inner surface of the first portion is a concave surface, while the radially inner surface of the second portion is a cone. It is a surface or a convex surface.

  In this specification, the conical surface is included in the concave surface, but not included in the convex surface.

  In the sealing device having the conventional configuration, the inventor has a large deformation of the radially inner axial lip portion on the core metal member side, and stress concentration occurs in this portion. As a result, the lifetime of the sealing device was shortened.

  According to the embodiment, the radially inner surface of the first portion is a concave surface in a state before assembly before the elastic member is incorporated into the slinger. Unlike the case where the inner surface of the first axial lip is convex, in the initial state of the built-in state, the second axial lip is not in contact with the fixed portion of the slinger. It is not necessary to intensively and excessively deform a part on the base side, and by deforming the entire first part substantially evenly in its extending direction, the second axial lip can be moved with respect to the fixing part of the slinger. Can be contactless. Therefore, local and excessive stress is not applied to a part of the first portion, so that the durability of the second axial lip can be remarkably improved and the life of the sealing device can be extended.

  Further, according to the above embodiment, the radially inner surface of the second portion is a conical surface or a convex surface in the state before the assembly, and thus the radially inner surface of the second portion. Compared with the case where the surface of the second axial lip is concave, the contact surface pressure between the second axial lip and the flange portion of the slinger can be reduced, and wear of the second axial lip can be suppressed. Therefore, since the time until the second axial lip contacts the fixed portion of the slinger can be lengthened, compared to the case where the radially inner surface of the second portion is concave, A state in which the torque is remarkably small can be maintained for a long time.

  In the sealing device of one embodiment, the inner surface of the second portion in the radial direction is smoothly connected.

  The term “smoothly connected” means that the radially inner surface of the second portion is in a state that can be differentiated from one end to the other end in the axial section of the sealing device.

  According to the embodiment, since the inner surface in the radial direction of the second portion is smoothly connected, the stress generated due to the deformation of the second axial lip at the time of assembly is applied to the entire second portion. Can be distributed almost evenly. Further, the second axial lip can be easily deformed radially outward at the time of assembly, and the second axial lip can be used in a non-wearing state during use after the first and second axial lips are assembled. And a predetermined clearance can be easily and accurately generated between the slinger and the fixed portion of the slinger.

  Further, in the sealing device according to an embodiment, the curvature of the radially inner surface of the first portion goes outward in the axial direction in the axial section in the state before the assembly. It grows according to.

  The phrase “increasing in the axial direction outwards” includes that in the axial cross section, the radially inner surface of the first portion goes outward in the axial direction. In addition, a case where a portion where the curvature is partially constant is included is also included. For this reason, for example, in the above wording, in the axial cross section, the radially inner surface of the first portion is smoothly connected to the conical surface located on the base side and the conical surface, and the spheroid The case where it consists of the concave surface which consists of a surface etc. is included.

  According to the embodiment, in the state before the assembly, in the axial section, the curvature of the inner surface in the radial direction of the first portion increases as it goes outward in the axial direction. As a result, the stress caused by the deformation of the second axial lip during assembly can be distributed evenly over the entire first portion, and the non-contact state with respect to the fixed portion of the second axial lip. When this is realized, it is possible to reliably prevent local stress concentration from occurring in the first portion.

  According to the sealing device of the present invention, the elastic member is in a non-contact state with the fixing portion of the slinger in a non-wearing state after use after the elastic member is incorporated into the slinger, There is no lip. Therefore, in the non-wearing state, the torque can be drastically reduced, and the fuel consumption of an automobile or the like having this sealing device can be reduced.

  Further, according to the sealing device of the present invention, in the second axial lip, the bent portion having a portion located at the radially innermost position is provided between the protruding portion and the flange portion of the slinger in the axial direction. The bent portion has a portion that overlaps the protruding portion in the axial direction when the elastic member is positioned and when the elastic member is not used after being installed in the slinger. The protruding portion can prevent the bent portion from moving in the axial direction, and the axial position of the bent portion can be limited between the protruding portion and the flange portion. Therefore, it is possible to prevent the slinger, the elastic member, and the cored bar member from separating.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an axial sectional view of a hub unit as a rolling bearing having a sealing device according to an embodiment of the present invention.

  The hub unit includes an inner shaft 2, an outer ring 3, an inner ring 4, a first ball 5, a second ball 6, a first sealing device 8 according to an embodiment of the present invention, and a first embodiment according to the present invention. Two sealing devices 9 are provided.

  The inner shaft 2 has a disc-shaped brake disk mounting flange 10 extending in the radial direction to which the brake disk 11 is mounted at one end in the axial direction. A plurality of bolt through holes are formed on a concentric circle centered on the approximate center of the brake disk mounting flange 10. With the brake disc 11 in contact with the brake disc mounting flange 10 and further with the wheel member 13 in contact with the brake disc 11, the end surface of the wheel member 13 opposite to the brake disc 11 side, The disk mounting flange 10 is fixed with a plurality of bolts 15.

  An inner ring 4 is externally fitted and fixed to the other axial end of the inner shaft 2. An angular type first raceway groove 16 is formed between the inner ring 4 and the brake disk mounting flange 10 in the inner shaft 2, while an angular type second raceway 16 is formed on the outer peripheral surface of the inner ring 4. A raceway groove 17 is formed.

  The outer ring 3 is arranged on the other end side of the brake disc mounting flange 10 in the inner shaft 2 so as to face the inner shaft 2 in the radial direction. The outer ring 3 has a vehicle body side mounting flange 14 that extends in the radial direction on the other end side in the axial direction. A plurality of bolt through holes for inserting bolts for attaching the vehicle body side mounting flange 14 to the vehicle body side (knuckle) are formed in the disk-shaped vehicle body side mounting flange 14. The outer ring 3 has an angular third track groove 26 and a fourth track groove 27 that are axially spaced from each other on the inner peripheral surface of the outer ring 3, and the angular third track groove 26 is an angular type. It is located on the one end side with respect to the fourth track groove 27.

  The first ball 5 is spaced apart from the first raceway groove 16 of the inner shaft 2 and the third raceway groove 26 of the outer ring 3 by a predetermined distance in the circumferential direction while being held by the cage 18. Are arranged. The second ball 6 is held at a predetermined interval in the circumferential direction while being held by the cage 19 between the second raceway groove 17 of the inner ring 4 and the fourth raceway groove 27 of the outer ring 3. Several are arranged.

  The first sealing device 8 is disposed in the vicinity of the opening on the one end side (the brake disc mounting flange 10 side) in the axial direction between the inner shaft 2 and the outer ring 3. The first sealing device 8 seals the opening on the one end side of the space between the inner shaft 2 and the outer ring 3. On the other hand, the second sealing device 9 is disposed between the inner ring 4 and the outer ring 3 in the vicinity of the opening on the other end side in the axial direction (the side opposite to the brake disk mounting flange 10 side). The second sealing device 9 seals the opening on the other end side of the space between the inner ring 4 and the outer ring 3.

  2 and 3 are cross-sectional views illustrating the structure of the first sealing device 8 in detail. Specifically, FIG. 2 is a cross-sectional view in the axial direction showing the positional relationship among the cored bar member 50, the elastic member 51, and the slinger 52 at the assembly position. FIG. 2 shows the position of the elastic member 51 at the assembly position of the elastic member when it is assumed that the elastic member 51 does not receive a force from the slinger 52. On the other hand, FIG. 3 shows the position of the elastic member 51 and the position of the slinger 52 in a state where the elastic member 51 is assembled to the slinger 52 and in a non-wearing state when the elastic member 51 is not worn. It is sectional drawing shown. The second sealing device 9 has the same structure as the first sealing device 8. The description of the second sealing device 9 is omitted from the description of the first sealing device 8.

  As shown in FIG. 2, the first sealing device (hereinafter simply referred to as a sealing device) 8 includes a cored bar member 50, an elastic member 51, and a slinger 52. The metal core member 50 is formed in an annular shape and has an L-shaped cross section. The core metal member 50 includes a cylindrical axially extending portion 60 as a fixed portion and a radially extending portion 61. The axially extending portion 60 is fitted and fixed to the inner peripheral surface of the outer ring 3 (see FIG. 1, not shown in FIG. 2). The radially extending portion 61 extends substantially inward in the radial direction from the other end side in the axial direction on the inner peripheral surface of the axially extending portion 60 (the left side in the drawing of FIG. 2).

  The slinger 52 is formed in an annular shape and has an L-shaped cross section. The slinger 52 has a cylindrical fixing portion 65 and a flange portion 66 connected to the fixing portion 65. The fixing portion 65 has an inner peripheral surface 68 and an outer peripheral surface 69. The inner peripheral surface 68 of the fixing portion 65 is fixed by being fitted on the outer peripheral surface of the inner shaft 2. On the other hand, the outer peripheral surface 69 of the fixed portion 65 has an annular projecting portion 70 that projects outward in the radial direction of the outer peripheral surface 69. The protruding portion 70 extends in the circumferential direction of the outer peripheral surface 69 of the fixing portion 65 of the slinger 52. In the second sealing device 9, needless to say, the member to which the slinger is fixed is the inner ring 4. The flange portion 66 extends from the end portion on the outer side in the axial direction (the right side in the drawing) of the outer peripheral surface of the fixed portion 65 to the outer side in the substantially radial direction. The flange portion 66 is located outward in the axial direction of the hub unit with respect to the radially extending portion 61 of the cored bar member 50. Most of the flange portion 66 excluding a part on the inner side in the radial direction is opposed to the radially extending portion 61 in the axial direction through a gap.

  The elastic member 51 is formed in an annular shape, and the axially outward end surface of the radially extending portion 61 connected to the entire inner peripheral surface of the axially extending portion 60 and the radially extending portion 61 connected to the inner peripheral surface of the axially extending portion 60. It is fixed to the core metal member 50 so as to cover the entire surface. The elastic member includes a base 53, a first axial lip 54, and a second axial lip 55. Specifically, the elastic member 51 is made of a rubber material. As the rubber material, nitrile rubber, hydrogenated nitrile rubber, acrylic rubber, silicon rubber, or fluorine rubber is preferably used.

  The base portion 53 is disposed along the inner peripheral surface of the axially extending portion 60 and the end surface of the radially extending portion 61 on the outer side in the axial direction. The base portion 53 is fixed to the inner peripheral surface of the axially extending portion 60 and the outer end surface of the radially extending portion 61. The first axial lip 54 extends from the base 53 to the outer ring 3 (see FIG. 1) side and the axially outer side (flange portion 66 side).

  The second axial lip 55 is spaced radially from the first axial lip 54 on the radially inner shaft 2 (see FIG. 1) side (inward radial direction) of the first axial lip 54. Is located. The second axial lip 55 has a first portion 56, a second portion 57, and a bent portion 72. The first portion 56 extends from the base 53 to the radially inner shaft 2 side and the axially outward side, while the second portion 57 is radially outwardly 3 side and axially outward. Extends to the side. The bent portion 72 is located between the first portion 56 and the second portion 57 and connects the first portion 56 and the second portion 57. The bent portion 72 has a substantially V-shaped cross section or a substantially U-shaped cross section. In the cross section in the axial direction, the tip of the bent portion 72 is located at the innermost side in the radial direction.

  As shown in FIG. 2, the position of the elastic member 51 when it is assumed that the elastic member 51 does not receive a force from the slinger 52 overlaps the slinger 52 at the assembly position. Specifically, the axially outer tip of the first axial lip 54 of the elastic member 51 and the axially outer tip of the second axial lip 55 of the elastic member 51 are the flange portions 66 of the slinger 52. And the bent portion 72 of the second axial lip 55 overlaps the fixing portion 65 of the slinger 52.

  In addition, as shown in FIG. 2, in a state before the elastic member 51 is assembled into the slinger 52, the radially inner surface 58 of the first portion 56 is a concave surface, whereas the radial direction of the second portion 57. The inner surface 59 is a conical surface. In the cross section in the axial direction, the curvature of the inner surface 58 in the radial direction of the first portion 56 increases toward the outer side in the axial direction (flange portion 66 side). Specifically, in the axial cross section, the radially inner surface 58 of the first portion 56 is smoothly connected to the substantially conical surface portion located on the base 53 side and the conical surface portion. At the same time, it is composed of a portion consisting of a part of a substantially spheroidal surface whose curvature increases toward the outside in the axial direction (flange portion 66 side).

  The inner surface 59 in the radial direction of the second portion 57 is differentiable from one end to the other end in the axial section, and the surface 59 is smoothly connected.

  As shown in FIG. 3, the first axial lip 54 and the second portion 57 of the second axial lip 55 are formed by the shaft of the sealing member and the slinger 52 having the cored bar member 50 and the elastic member 51 when assembled. It slides on the flange 66 of the slinger 52 by relative rotation about the center. In addition, as shown in FIG. 3, the second axial lip 55 is positioned at a radial interval with respect to the fixed portion 65 of the slinger 52 in the assembled state and in the non-wearing state after use. is doing. That is, as shown in FIGS. 2 and 3, during assembly, the first axial lip 54 and the second portion 57 of the second axial lip 55 are radially outward along the surface of the flange portion 66 of the slinger 52. So that the bent portion 72 of the second axial lip 55 moves radially outward so that the bent portion 72 floats outward from the outer peripheral surface of the fixed portion 65 in the radial direction. It has become.

  As shown in FIG. 2, the bent portion 72 of the second axial lip 55 is positioned between the protruding portion 70 of the slinger 52 and the flange portion 66 of the slinger 52 in the axial direction, and the elastic member 51. When the bent portion 72 is not used after being installed in the slinger 52, the bent portion 72 is a portion that overlaps the protruding portion 70 of the slinger 52 in the axial direction (from FIG. Corresponding to the inner part).

  As is clear from FIG. 2, the position of the bent portion 72 when it is assumed that the elastic member 51 does not receive force from the slinger 52 is set so as to overlap the fixed portion 65. The bending portion 72 is in contact with the fixing portion 65 of the slinger 52 in a state in which the pressing force of the second axial lip 55 against the flange portion 66 is reduced by a predetermined force or more due to wear of the second portion 57 of the second axial lip 55. The sliding portion 65 is configured to slide.

  Due to wear of the second portion 57 of the second axial lip 55, the pressing force against the flange portion 66 of the second axial lip 55 is reduced by a predetermined force or more, and the bent portion 72 of the second axial lip 55 fixes the slinger 52. Even in the state of being in contact with the portion 65, the protruding portion 70 of the slinger 52 is positioned at a distance from the second axial lip 55.

  In addition, as shown in FIG. 3, the bent portion 72 of the second axial lip 55 in the assembled state and in the non-wearing state during use after the assembly, the protruding portion 70 of the slinger 52 and the slinger 52 A portion where the bent portion 72 overlaps with the protruding portion 70 of the slinger 52 in the axial direction in a state of being located between the flange portion 66 (from FIG. 3, this is an inner portion in the radial direction of the bent portion 72. Is equivalent).

  In any state, the second axial lip 55 and the protruding portion 70 of the fixing portion 65 of the slinger 52 are opposed to each other in the radial direction through a narrow passage. In any state, the second axial lip 55 and the protruding portion 70 of the fixing portion 65 of the slinger 52 constitute a labyrinth seal.

  In the space formed by the first axial lip 54, the second axial lip 55, and the slinger 52, or in the space where the second axial lip 55 and the slinger 52 face each other, an appropriate amount of grease is sealed or applied as a lubricant. . By this grease, the sliding portion between the first axial lip 54 and the slinger 52 and the sliding portion between the second axial lip 55 and the slinger 52 are lubricated.

  FIG. 4 shows the contact load ratio with respect to the total contact load of each lip when the lip is in a non-wearing state in each of the comparative sealing device and the sealing device of the above embodiment in one experimental example. It is a figure which shows ratio of the total contact load of the sealing device of the said embodiment with respect to the total contact load of the sealing device 270 of a comparative product.

  Here, the comparative sealing device 270 is a so-called pack-seal type sealing device having a cored bar member 250, an elastic member 251 and an L-shaped slinger 252 shown in FIG. 271 and a sealing device having two radial lips (a main lip 272 and an auxiliary lip 273).

  FIG. 7 shows a position where the elastic member 251 is present at the assembly position of the elastic member 251 when it is assumed that the elastic member 251 does not receive a force from the slinger 252 in the sealing device 270 of the comparative example.

  As shown in FIG. 4, in the comparative sealing device 270, the contact load ratio with respect to the total contact load of the radial lip (two in total) reaches 80%, whereas the contact load ratio with respect to the total contact load of the axial lip Is about 20%. From this, if the contact load of the radial lip can be reduced, the torque can be greatly reduced.

  Therefore, in the sealing device of the above embodiment that has only two axial lips and does not have a radial lip, the contact load ratio of the total contact load to the total contact load of the comparative product has reached only 40%, The contact load can be drastically reduced.

  FIG. 5 is a diagram showing the relationship between the rotational speed and the rotational torque in each of the comparative sealing device 270 and the sealing device of the embodiment in one experimental example.

  The torque of the sealing device of the above embodiment relative to the comparative product is about 50% of the torque of the sealing device of the comparative product from the region where the rotational speed is low to the high region. That is, the torque of the sealing device of the above embodiment is rapidly reduced as compared with the comparative product. This test was performed without using a lubricant (such as grease) in the sealing device of the above embodiment and the comparative sealing device 270.

According to the sealing device of the above-described embodiment, the elastic member 51 is in a non-contact state with the fixing portion 65 of the slinger 52 until the pressing force against the flange portion 66 of the second axial lip 55 is reduced by a predetermined force or more. Since the radial lip is not present, the torque is rapidly increased by about 50% as compared with the sealing device having the radial lip until the pressing force of the second axial lip 55 against the flange portion 66 is reduced by a predetermined force or more. Can be reduced. Therefore, the fuel consumption of an automobile or the like having this sealing device can be reduced, and the CO ₂ emission amount of the automobile or the like having this sealing device can be reduced, thereby contributing to the suppression of global warming.

  Further, in the sealing device of the above embodiment, compared to the configuration in which the radial contact lip exists, in the initial state of non-wear, there is no radial contact lip, so that the torque can be significantly reduced, while the radial The axial frictional force resulting from the absence of the directional contact lip is lost, and the core metal member 50 and the elastic member 51 may easily move in the axial direction relative to the slinger 52.

  However, according to the sealing device of the above embodiment, the elastic member 51 is attached to the slinger 52 in a state where the bent portion 72 is positioned between the protruding portion 70 and the flange portion 66 of the slinger 52 in the axial direction. Since the bent portion 72 has a portion that overlaps the protruding portion 70 in the axial direction when it is not used after being assembled, even if it is assembled, the elastic member 51 and the cored bar member with respect to the slinger 52 50, even if it moves in the axial direction, the protruding portion 70 prevents the bent portion 72 from moving in the axial direction, and the axial position of the bent portion 72 is limited between the protruding portion 70 and the flange portion 66. Thus, the elastic member 51 and the cored bar member 50 do not move in the axial direction without limitation with respect to the slinger 52. Therefore, the slinger 52, the elastic member 51, and the cored bar member 50 are not separated.

  Further, according to the sealing device of the above embodiment, the second axial lip 55 and the protruding portion 70 of the fixing portion 65 of the slinger 52 are opposed to each other in the radial direction through the narrow passage, Since the protruding part 70 of the fixing part 65 of the slinger 52 constitutes a labyrinth seal, the sealing performance of the sealing device can be improved.

  Further, according to the sealing device of the above-described embodiment, the radially inner surface 58 of the first portion 56 is a concave surface in a state before assembly before the elastic member 51 is assembled into the slinger 52. Unlike the case where one portion is a convex surface, the second axial lip 55 is used to make the second axial lip 55 non-contact with the fixing portion 65 of the slinger 52 in a non-wearing state after use. It is not necessary to intensively and excessively deform a part on the base 53 side of the first portion 56 of the first portion 56, and by deforming the entire first portion 56 substantially uniformly in the extending direction, the second axial lip 55 is The fixing part 65 of the slinger 52 can be made non-contact. That is, since a part of the first portion 56 is not subjected to local and excessive stress, the durability of the second axial lip 55 can be remarkably improved and the life of the sealing device can be extended. it can.

  Further, according to the sealing device of the above-described embodiment, the radially inner surface 59 of the second portion 57 is a conical surface in a state before being assembled, and therefore the radially inner surface of the second portion 57. Compared with the case where the surface is concave, the contact surface pressure between the second axial lip 55 and the flange portion 66 of the slinger 52 can be reduced, and wear of the second axial lip 55 can be suppressed. Therefore, the time until the bent portion 72 of the second axial lip 55 contacts the fixing portion 65 of the slinger 52 can be increased, and the radially inner surface of the second portion is concave. Compared to the case, a state in which the torque is remarkably small can be maintained for a long time.

  Further, according to the sealing device of the above embodiment, since the radially inner surface 59 of the second portion 57 is smoothly connected, the stress generated due to the deformation of the second axial lip 55 during assembly. Can be distributed and evenly distributed over the second portion 57 as a whole. In addition, the second axial lip 55 can be easily deformed radially outward at the time of assembly, and the second axial lip 55 and the slinger are in a non-wearing state when the second axial lip 55 is used. A predetermined clearance can be easily and accurately generated between the fixing portion 65 and the fixing portion 65.

  Further, according to the sealing device of the above-described embodiment, as the curvature of the radially inner surface of the first portion 56 goes outward in the axial direction in the axial cross section in the state before assembly. Since it is large, the stress caused by the deformation of the second axial lip 55 at the time of assembly can be distributed and evenly distributed throughout the first portion 56, and the first portion 56 is locally localized. It is possible to reliably prevent stress concentration. Therefore, the lifetime of the sealing device can be further extended.

  Further, according to the sealing device of the above-described embodiment, the bending portion 72 is in a state where the pressing force of the second axial lip 55 against the flange portion 66 is reduced by a predetermined force or more due to wear of the second portion 57 of the second axial lip 55. However, even if the second axial lip 55 is worn away, the bent portion 72 as a radial lip is externally connected to the outer portion of the slender 52. Can prevent the muddy water from entering the space where the balls 8 and 9 of the hub unit are arranged.

  In the sealing device of the above embodiment, the protruding portion 70 formed on the outer peripheral surface of the slinger 52 is annular, but in the present invention, the protruding portion formed on the outer peripheral surface of the slinger is not annular. Also good.

  In the sealing device of the above embodiment, the inner surface 59 in the radial direction of the second portion 57 is a conical surface before being assembled, but in the present invention, the inner surface in the radial direction of the second portion. The other surface may be a convex surface in a state before incorporation.

  In the sealing device of the above embodiment, in the axial cross section, the surface 58 that is a concave surface located inward in the radial direction of the first portion 56 has a substantially conical surface-like portion located on the base 53 side, and Although it was smoothly connected to this conical surface-shaped portion, it consisted of a portion consisting of a part of a substantially spheroidal surface whose curvature increased toward the outside in the axial direction (flange portion 66 side), In the present invention, in the axial cross section, the curvature of the entire surface located inward in the radial direction of the first portion increases toward the conical surface or outward in the axial direction (flange portion side). It may be a part composed of a part of the spheroid. In this invention, if the surface located radially inward of the first portion has a shape in which the curvature increases in the axial direction in the axial direction outward (flange portion side), Any shape is possible.

  Further, in the above hub unit, the sealing device of the present invention is disposed in the vicinity of the openings on both sides in the axial direction of the ball arrangement space (lubricant enclosure space). Moving object (not a ball, it may be a roller, or both may be a ball) Even if it is arranged only near the opening on one side in the axial direction of the arrangement space (lubricant enclosure space) good.

  FIG. 6 is an enlarged cross-sectional view of the periphery of the sealing device 99 of the water pump provided with the sealing device 99 of the present invention.

  This water pump has a pump shaft 100, a mechanical seal 101, a pump housing 102, an outer ring 105, and a sealing device 99 of the present invention. The pump housing 102 has a drain hole 107 that penetrates the pump housing 102. The outer ring 105 is fitted and fixed to the inner peripheral surface of the pump housing 102.

  The pump shaft 100, the outer ring 105, and the sealing device 99 form part of a water pump bearing of the water pump. That is, although not shown, on the side indicated by the arrow a in FIG. 6 on the inner peripheral surface of the outer ring 105, a deep groove type raceway groove and a cylindrical raceway surface are spaced from each other in the axial direction and are closer to the sealing device 99. 6 is formed on the outer peripheral surface of the pump shaft 100 as indicated by an arrow a in FIG. 6 from the side closer to the sealing device 99 at an axial interval, and a deep groove type track groove and a cylindrical track. A surface is formed.

  Between the raceway groove of the outer ring 105 and the raceway groove of the pump shaft 100, a plurality of balls held in a cage are arranged at a predetermined interval in the circumferential direction. A plurality of cylindrical rollers held by a cage are arranged between the cylindrical raceway surface of the outer ring 105 and the cylindrical raceway surface of the pump shaft 100 at a predetermined interval in the circumferential direction. ing.

  The cored bar portion 150 of the sealing device 99 is fitted and fixed to the inner peripheral surface of the outer ring 105, while the slinger 152 of the sealing device 99 is fitted and fixed to the outer peripheral surface of the pump shaft 100. Yes. The sealing device 99 seals the opening on the mechanical seal 101 side between the outer ring 105 and the pump shaft 100. In this manner, the cooling water in the pump chamber leaking from the mechanical seal 101 in the direction indicated by the arrow b is prevented from entering the water pump bearing.

  The leaked cooling water in the pump chamber is surely discharged to the outside in the direction indicated by the arrow c through the drain hole 107 formed in the pump housing 102. In FIG. 6, reference numeral 111 denotes a rubber sleeve of the mechanical seal 101, and 110 denotes a coil spring of the mechanical seal 101.

  When the sealing device of the present invention is installed in the water pump as in the water pump shown in FIG. 6, the torque of the water pump bearing in the water pump can be reduced, and the fuel consumption of an automobile or the like having the water pump can be reduced.

  Further, a bent portion 172 of the second axial lip 155 located radially inward of the first axial lip 154 is located between the protruding portion 170 of the slinger 152 and the flange portion 166 of the slinger 152 in the axial direction. The bent portion 172 has a portion that overlaps the protruding portion 170 in the axial direction when the elastic member 151 is not used after the elastic member 151 is incorporated in the slinger 152. Therefore, even if the elastic member 151 and the core metal member 150 move in the axial direction with respect to the slinger 152, the protrusion 170 prevents the bending portion 172 from moving in the axial direction, and the axis of the bending portion 172 The position in the direction is limited between the projecting portion 170 and the flange portion 166, and the elastic member 151 and the cored bar member 150 are not moved in the axial direction without any limit with respect to the slinger 152. Therefore, it is possible to prevent the cored bar portion 150 and the elastic portion 151 from being separated from the slinger 152 when the water pump is transported or assembled.

  In the above embodiment, the sealing device of the present invention is set to a hub unit or a water pump. However, the sealing device of the present invention may be set between the rotor and the stator in the motor, and in this case, the operating cost of the motor can be reduced. The sealing device of the present invention may be disposed between the inner ring and the outer ring of a simple rolling bearing. The sealing device of the present invention includes a first member having an inner peripheral surface and a second member having an outer peripheral surface, and the first member and the second member are included in the first member. The device can be installed in any machine as long as it is a device facing the radial direction of the peripheral surface. And while being able to reduce the operating cost of the machine which installed the sealing device of this invention, it can prevent that a sealing device spreads in the machine.

It is sectional drawing of the axial direction of the hub unit which has the sealing device of one Embodiment of this invention. It is an expanded sectional view of the whole sealing device of the above-mentioned embodiment. It is an expanded sectional view around the 1st and 2nd axial lip of the sealing device of the above-mentioned embodiment. In one experimental example, the ratio of the contact load to the total contact load of each lip in each of the comparative sealing device and the sealing device of the above embodiment, and the sealing device of the above embodiment with respect to the total contact load of the comparative sealing device. It is a figure which shows ratio of all the contact loads. It is a figure which shows the relationship between the rotation speed and rotational torque in each of the sealing device of the said comparative product and the sealing device of the said embodiment in one experimental example. It is an expanded sectional view of the above-mentioned sealing device periphery of a water pump provided with the sealing device of the present invention. It is an expanded sectional view of the whole sealing device of a comparative product.

Explanation of symbols

2 Inner shaft 3 Outer ring 4 Inner ring 5 First ball 6 Second ball 8 First sealing device 9 Second sealing device 50,150 Core member 51,151 Elastic member 52,152 Slinger 53 Base 54,154 First axial Lip 55,155 Second axial lip 56 First part 57 Second part 58 Radial inner surface of first part 59 Radial inner surface of second part 60 Axial extension 61 Radial extension Residual portion 65,165 Fixed portion 66,166 Flange portion 70,170 Protruding portion 72,172 Bending portion of second axial lip 99 Sealing device

Claims (2)

A cored bar member having a cylindrical fixing part and a radially extending part extending from the fixing part in a substantially radial direction of the fixing part;
An elastic member fixed to the cored bar member;
A slinger having a cylindrical fixing portion having a protruding portion on the outer periphery and a flange portion extending substantially in the radial direction from the fixing portion,
The elastic member is
A base fixed to the radially extending portion of the core member;
A first axial lip extending from the base and sliding on the flange;
A second axial lip that is positioned between the first axial lip and the fixed portion of the slinger and slides on the flange;
The second axial lip is connected to the first portion extending from the base in a direction approaching the fixing portion of the slinger, and is connected to the first portion via a bent portion, and is connected to the fixing portion of the slinger. A second portion that extends in a direction away from the flange portion and slides on the flange portion, while the elastic member is incorporated into the slinger and is in a non-wearing state during use after installation. Located at a distance from the fixed part,
When the bent portion is positioned between the projecting portion and the flange portion of the slinger in the axial direction, the elastic member is not used after being installed after being installed in the slinger. The sealing device according to claim 1, wherein the bent portion has a portion overlapping the protruding portion of the fixed portion of the slinger in the axial direction. The sealing device according to claim 1,
The protruding portion is annular and extends in the circumferential direction of the fixed portion of the slinger,
In a state after the elastic member is incorporated in the slinger, and in a state where the pressing force of the second axial lip against the flange portion is reduced by a predetermined force or more due to wear of the second axial lip, the bent portion is A sealing device that slides on the fixed portion of the slinger.

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