JP2010060138A - Rolling bearing and seal for the rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing with a seal, inexpensive, superior in rust preventing capability, compact without impairing waterproof and dustproof functions and superior in appearance. <P>SOLUTION: An approximately cylindrical fitting part 73 is provided on the outer peripheral side of a bored disk-shaped base 71 of the seal 7, and is fitted to the outer peripheral side of an outer ring 3 to fix the seal 7. Since a chamfered part 38 of the outer ring 3 of the rolling bearing 1 in which rust is easily generated is completely covered from the lateral face 31 of the outer ring 3 to the outer periphery, high rust preventing effects can be obtained. Since the fitting part 73 does not enter into an annular space 4, the necessity of a configuration for avoiding interference with a steel ball 5 and a cage 6 is eliminated, and the compact rolling bearing 1 with the seal 7 can be achieved. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a rolling bearing and a seal for a rolling bearing.

  In a rolling bearing, a sealed rolling bearing is used in order to enclose grease inside and prevent water and dust from entering from the outside.

  FIG. 8 is a cross-sectional view of a suitable portion showing an example of the structure of a conventional rolling bearing 901 with a seal. The rolling bearing 901 includes an inner ring 902, an outer ring 903, a plurality of steel balls 905 arranged in an annular space 904 between the inner ring 902 and the outer ring 903, and a constant interval between the steel balls 905 in the annular space 904. In order to maintain, a retainer 906 that rotatably holds the steel ball 905 and a pair of seals 907 that close the annular space 904 from both ends are provided.

  The seal 907 includes a substantially disc-shaped base portion 971 with a hole in the center, an annular lip 972 extending on the inner peripheral side of the base portion 971, and a substantially cylindrical fitting extending on the outer peripheral side of the base portion 971. Part 973.

  The lip 972 is rotatable relative to the inner ring 902 while elastically contacting the outer peripheral side of the inner ring 902. The fitting portion 973 is fitted to the inner peripheral side of the outer ring 903 and is fixed to the outer ring 903.

  In this manner, by using the seal 907, it is possible to enclose grease in the rolling bearing 901, that is, the annular space 904, or to prevent water and dust from entering from the outside.

  However, the conventional rolling bearing 901 has the following problems.

  First, even if it is possible to prevent water and mud from entering the rolling bearing 901 by using the seal 907, the outside of the rolling bearing 901 may be exposed to water and mud, and rust is generated from the outside. As a result, the function and appearance of the bearing 901 itself and a product incorporating the same may be impaired.

  For this reason, from the viewpoint of rust prevention, the outer ring 903 and the inner ring 902 are made of stainless steel. (For example, SUS440) is often used for configuration. However, stainless steel is expensive and the rust prevention effect is not absolute.

  In order to solve such a problem, a sealing device has been proposed in which an end surface seal portion that is in close contact with a side surface (end surface portion) of an outer ring (housing) is provided (see Patent Document 1). If this sealing device is used, generation | occurrence | production of the rust from the side surface of an outer ring | wheel can be prevented to some extent.

  However, the rust is most likely to occur in the outer ring is a chamfered portion where the cut surface remains as it is, and there is a problem that the rust generated from this rolls and proceeds to the entire rolling bearing.

  Second, in the conventional rolling bearing 901 with a char, when the seal 907 is fixed to the outer ring 903, the fitting portion 973 is fitted into the inner peripheral side of the outer ring 903. For this reason, in order to avoid interference between the fitting portion 973 and the steel ball 905 or the cage 906 existing in the annular space 904, the fitting depth of the fitting portion 973 is reduced, or the width (axial dimension) of the outer ring 903 is set. It was necessary to increase the thickness.

  However, if the fitting depth of the fitting portion 973 is too small, the fixing force of the seal 907 to the outer ring 903 is insufficient, and the waterproof function / dustproof function is also deteriorated. On the other hand, when the width of the outer ring 903 is increased, this problem is solved, but it cannot be used for a product that requires compactness.

Third, when viewed from the side, the conventional rolling bearing 901 with a seal has a side surface 921 of the inner ring 902, a side surface 974 of the seal 907, and a side surface 931 of the outer ring 903 arranged concentrically. Of these, the side surface 974 of the seal 967 and the side surface 931 of the outer ring 903 are often visible from the outside in a state where the rolling bearing 901 is assembled to the product, causing the appearance of the product to be complicated.
In the above-described conventional technology, the conventional technology that seals both ends of the annular space 904 and encloses grease or prevents water or dust from entering from the outside has been described. Depending on the combination with other parts, and in order to prevent water and dust from entering from the outside, a rolling bearing as described in Patent Document 2 having a configuration in which one end side of the annular space 904 is sealed is also employed. Has been.

  JP-A-2005-351392   JP 2002-327667 A

The present invention solves the problems of such conventional rolling bearings, and provides a bearing that is inexpensive, excellent in rust prevention power, compact without impairing waterproof and dustproof functions, and excellent in appearance. Objective.

A rolling bearing according to the present invention is a rolling bearing including an inner ring, an outer ring, a plurality of rolling elements disposed in an annular space between the inner ring and the outer ring, and a seal that closes an end of the annular space. The seal is a substantially disc-shaped base portion having a hole in the center, and an annular lip extending on the inner peripheral side of the base portion. It is characterized by comprising a rotatable lip and a substantially cylindrical fitting portion extending on the outer peripheral side of the base portion and fitted on the outer peripheral side of the outer ring and fixed to the outer ring.

A seal for a rolling bearing according to the present invention is for closing an end of the annular space of a rolling bearing including an inner ring, an outer ring, and a plurality of rolling elements arranged in an annular space between the inner ring and the outer ring. A seal having a substantially disc-shaped base portion with a hole in the center and an annular lip extending on the inner peripheral side of the base portion, and elastically contacting the outer peripheral side of the inner ring with respect to the inner ring And a lip that can be rotated relative to each other, and a substantially cylindrical fitting portion that extends to the outer peripheral side of the base portion and is fitted to the outer peripheral side of the outer ring and is fixed to the outer ring. To do.

The features of the present invention can be broadly shown as described above, but the configuration and contents thereof, together with the objects and features, will be further clarified by the following disclosure in view of the drawings.

A rolling bearing according to a first invention of the present application is a rolling bearing including an inner ring, an outer ring, a plurality of rolling elements disposed in an annular space between the inner ring and the outer ring, and a seal that closes an end of the annular space. It is a bearing.
The seal is a substantially disk-shaped base with a hole in the center, and an annular lip that extends to the inner periphery of the base and can rotate relative to the inner ring while elastically contacting the outer periphery of the inner ring And a fitting portion that is a substantially cylindrical fitting portion that extends to the outer peripheral side of the base portion and is fitted to the outer peripheral side of the outer ring and is fixed to the outer ring.

A seal for a rolling bearing according to a fourth invention of the present application includes an end of the annular space of a rolling bearing including an inner ring, an outer ring, and a plurality of rolling elements arranged in an annular space between the inner ring and the outer ring. It is a seal for closing. The seal is a substantially disk-shaped base portion having a hole in the center, and an annular lip extending one on the inner peripheral side of the base portion, and rotates relative to the inner ring while elastically contacting the outer peripheral side of the inner ring. A possible lip, and a substantially cylindrical fitting portion that extends to the outer peripheral side of the base portion, and a fitting portion that is fitted to the outer peripheral side of the outer ring and fixed to the outer ring.

  As described above, in the rolling bearing according to the first invention of the present application and the rolling bearing seal according to the fourth invention of the present application, the seal is a substantially cylindrical fitting portion extending on the outer peripheral side of the base portion, and the outer peripheral side of the outer ring. A fitting portion is provided that is fitted to be fixed to the outer ring.

  Therefore, the chamfered portion of the outer ring of the rolling bearing that is most likely to generate rust can be completely covered with the base portion and the fitting portion of the seal formed so as to continuously cover from the side surface to the outer periphery of the outer ring. As a result, a high rust prevention effect can be obtained without using expensive stainless steel.

  Further, since the seal is fixed by fitting the fitting portion into the outer peripheral side of the outer ring, the fitting portion does not enter the annular space. Therefore, in order to avoid interference with rolling elements and cages existing in the annular space, as in the case of conventional rolling bearings with seals, it is necessary to make the fitting depth shallower or increase the width of the outer ring. There is no. As a result, it is possible to realize a compact rolling bearing with a seal without reducing the waterproof function / dustproof function.

  Furthermore, since the side of the outer ring is completely covered with the base of the seal on the disc together with the end of the annular space, when viewed from the side of the rolling bearing, only the side of the inner ring and the side of the base of the seal are visible. The side of the outer ring is not visible. For this reason, the external appearance of the product in which the rolling bearing is assembled is not complicated.

  That is, it is possible to realize a bearing that is inexpensive and excellent in rust prevention power, is compact without impairing the waterproof function and dustproof function, and has an excellent appearance.

  The rolling bearing according to the second invention of the present application is the rolling bearing of the first invention of the present application, wherein the seal is a metal cored bar formed integrally from the base portion to the fitting portion, and the seal is mounted on the rolling bearing. And a rubber-like elastic body formed in close contact with the core metal so that the core metal is not exposed to the outside of the bearing.

  The rolling bearing seal according to the fifth invention of the present application is the rolling bearing seal according to the fourth invention of the present application, in which the metal cored bar formed integrally from the base portion to the fitting portion and the seal are mounted on the rolling bearing. And a rubber-like elastic body formed in close contact with the core bar so that the core bar is not exposed to the outside of the bearing.

  Thus (in the rolling bearing according to the second invention of the present application and the rolling bearing seal according to the fifth invention of the present application, a metal cored bar formed integrally from the base portion of the seal to the fitting portion is disposed. Yes.

  Therefore, a large fixing force can be obtained when the fitting portion is fitted and fixed to the outer peripheral side of the outer ring. As a result, the seal can be prevented from falling off or loosening from the outer ring, and the chamfered portion of the outer ring can be covered more reliably. For this reason, a rust prevention effect can be maintained more reliably.

  In addition, since the seal is unlikely to fall off or loosen from the outer ring, the waterproof function and the dust-proof function for the annular space can be reliably maintained at any time.

  Further, in the rolling bearing according to the second invention of the present application and the rolling bearing seal according to the fifth invention of the present application, the rubber core is made in close contact with the metal core so that the metal core metal of the seal is not exposed to the outside of the rolling bearing. Try to form a body.

  Therefore, even when the rolling bearing is exposed to water or mud from the outside, it is possible to prevent water or mud from reaching the cored bar and to prevent the cored bar from rusting.

  Moreover, since the cored bar cannot be seen from the outside of the rolling bearing, the aesthetic appearance is not impaired.

  The rolling bearing according to the third invention of the present application is the rolling bearing according to the first or second invention of the present application, wherein the seal is an annular protrusion provided on the outer periphery of the fitting portion, and fixedly accommodates the outer ring of the rolling bearing. An annular protrusion fitted into an annular groove on the cylindrical inner surface of the outer ring housing member is provided.

  The rolling bearing seal according to the sixth invention of the present application is a rolling bearing seal according to the fourth or fifth invention of the present application, which is an annular protrusion provided on the outer periphery of the fitting portion and fixedly accommodates the outer ring of the rolling bearing. And an annular protrusion fitted into the annular groove on the cylindrical inner surface of the outer ring housing member.

  Thus, in the rolling bearing according to the third invention of the present application and the rolling bearing seal according to the sixth invention of the present application, the annular protrusion is provided on the outer periphery of the fitting portion of the seal. The annular protrusion is fitted into an annular groove on the cylindrical inner surface of the outer ring housing member that fixedly houses the outer ring of the rolling bearing.

  That is, for example, an annular groove is provided in advance on the cylindrical inner surface of the outer ring housing member, and an annular protrusion provided on the outer periphery of the fitting portion of the seal is formed of an elastic body on rubber. The outer diameter of the annular protrusion of the seal is configured to be slightly larger than the inner diameter of the cylindrical inner surface of the outer ring housing member, and the annular protrusion of the seal is forcibly inserted into the cylindrical inner surface of the outer ring housing member while being elastically deformed. . When the insertion is completed, the annular protrusion of the seal is elastically restored in the annular groove of the outer ring housing member.

  Thus, by forcibly fitting the annular projection of the seal into the annular groove of the outer ring housing member, the coupling force between the seal and the outer ring housing member can be strengthened, and thus the rolling bearing and the outer ring housing member can be strengthened. Can be a strong power.

  As a result, the intrusion of water and mud from the outer periphery of the outer ring can be prevented, and the rust prevention effect can be improved.

  Further, when the outer ring housing member is molded from a synthetic resin or the like, the rolling bearing with the seal attached is used as an insert product, and a composite part including the rolling bearing and the outer ring housing member is insert-molded, so that the rolling bearing and the outer ring housing member are The binding force can be further strengthened.

  As a result, the intrusion of water and mud from the outer periphery of the outer ring can be completely prevented, and the rust prevention effect can be further ensured.

  1 is a perspective view showing an external configuration of a rolling bearing 1 with a seal according to an embodiment of the present invention.   1 is a front view of a rolling bearing 1. FIG.   2 is a right side view of the rolling bearing 1. FIG.   It is the IV-IV sectional view taken on the line in FIG.   It is the VV sectional view taken on the line in FIG.   FIG. 5 is a cross-sectional view corresponding to FIG. 4, showing a state in which the rolling bearing 1 is housed in an outer ring housing member 8.   FIG. 5 is a cross-sectional view corresponding to FIG. 4, showing a state in which the rolling bearing 1 is housed in another outer ring housing member 9.   It is sectional drawing which shows an example of the structure of the conventional rolling bearing 901 with a seal.

  FIG. 1 is a perspective view showing an external configuration of a rolling bearing 1 with a seal according to an embodiment of the present invention. FIG. 2 is a front view of the rolling bearing 1. FIG. 3 is a right side view of the rolling bearing 1. 4 is a cross-sectional view taken along line IV-IV in FIG. 5 is a cross-sectional view taken along line VV in FIG. FIG. 6 is a cross-sectional view corresponding to FIG. 4 showing a state in which the rolling bearing 1 is housed in the outer ring housing member 8. FIG. 7 is a cross-sectional view corresponding to FIG. 4 showing a state in which the rolling bearing 1 is housed in another outer ring housing member 9.

  As shown in detail in FIG. 4, the rolling bearing 1 includes an inner ring 2, an outer ring 3, a plurality of steel balls 5 disposed in an annular space 4 between the inner ring 2 and the outer ring 3, and an annular space 4. In order to keep the distance between the steel balls 5 constant, a retainer 6 that rotatably holds the steel balls 5 and a pair of seals 7 that close both ends of the annular space 4 are provided.

  The seal 7 includes a substantially disc-shaped base 71 having a hole in the center, an annular lip 72 extending on the inner peripheral side of the base 71, and a substantially cylindrical fit extending on the outer peripheral side of the base 71. Part 73.

  The lip 72 is rotatable relative to the inner ring 2 while elastically contacting the outer peripheral side of the inner ring 2.

  In the example of FIG. 4, the outer periphery of the inner ring 2 is connected to the small diameter portion 22 formed near the side surface 21, the large diameter portion 23 formed adjacent to the small diameter portion 22, and the small diameter portion 22 and the large diameter portion 23. A step groove 24 is formed, and a rolling groove 25 in which the steel ball 5 rolls is formed at the center of the large diameter portion 23. The tip end of the lip 72 is configured to elastically contact the stepped portion 24.

  The fitting part 73 is fixed to the outer ring 3 by fitting into the outer peripheral side of the outer ring 3.

  In the example of FIG. 4, the outer periphery of the outer ring 3 is formed adjacent to the medium diameter portion 36 formed near the side surface 31, the small diameter portion 32 formed adjacent to the medium diameter portion 36, and the small diameter portion 32. The large diameter portion 33, the step portion 37 that connects the medium diameter portion 36 and the small diameter portion 32, and the step portion 34 that connects the small diameter portion 32 and the large diameter portion 33. Between the side surface 31 and the medium diameter portion 36 is a chamfered portion 38. A rolling groove 35 in which the steel ball 5 rolls is formed at the center of the inner periphery of the outer ring 3.

  The seal 7 includes a metal core 75 integrally formed from the base 71 to the fitting portion 73, and the core 75 is not exposed to the outside of the rolling bearing 1 in a state where the seal 7 is mounted on the rolling bearing 1. And a rubber-like elastic body 76 formed in close contact with the core metal 75.

  That is, the cored bar 75 extends to the outer peripheral side of the disc-shaped portion 75a corresponding to the base portion 71 of the seal 7 and corresponding to the disc-shaped portion 75a having a hole in the center and the fitting portion 73 of the seal 7. A cylindrical portion 75b.

  The inner side (annular space 4 side) of the disc-shaped part 75a of the cored bar 75 is not covered with the rubber-like elastic body 76 except for the vicinity of the inner ring (the part following the lip 72). All other parts of the core metal 75 are covered with a rubber-like elastic body 76. Therefore, in a state where the seal 7 is mounted on the rolling bearing 1, the side surface 31 of the outer ring 3 and the inner side of the disk-shaped portion 75 a of the core metal 75 are in direct contact with each other part of the outer ring 3. The metal core 75 is in contact with the rubber elastic body 76.

  In order to fit the seal 7 into the outer ring 3, the seal 7 is pushed in from the side 31 side of the outer ring 3 so that the chamfered portion 38, the medium diameter portion 36, and the small diameter portion 32 of the outer ring 3 are covered by the fitting portion 73 of the seal 7.

  The inner surface of the disc-shaped portion 75 a of the core metal 75 of the seal 7 is in contact with the side surface 31 of the outer ring 3, and the end surface 77 of the fitting portion 73 of the seal 7 is in contact with the stepped portion 34 of the outer ring 3. .

  The outer diameter of the middle diameter portion 36 of the outer ring 3 is configured to be larger than the inner diameter of the fitting portion 73 of the seal 7 and substantially the same as the inner diameter of the cylindrical portion 75 b of the core metal 75. The outer diameter of the small diameter portion 32 of the outer ring 3 is configured to be slightly smaller than the inner diameter of the fitting portion 73 of the seal 7.

  As a result, when the seal 7 is fitted into the outer ring 3, the rubber-like elastic body 76 inside the fitting part 73 of the seal 7 is deformed by the inner diameter portion 36 of the outer ring 3, and the seal 7 is fixed to the outer ring 3. In this example, the outer diameter of the inner diameter portion 36 of the outer ring 3 is made substantially the same as the inner diameter of the cylindrical portion 75b of the core metal 7, so that a larger fixing force can be obtained. Therefore, it is possible to realize a rolling bearing with better waterproofness.

Further, on the outer circumference of the outer ring 3, a portion having an outer diameter smaller than the large diameter portion 33, that is, a medium diameter portion having an outer diameter smaller than the large diameter portion 33 and a small diameter portion 32 having an outer diameter smaller than the medium diameter portion 36, By constructing the inner periphery of the fitting portion 73 of the seal 7 on the outer periphery of the diameter portion 36 and the small diameter portion 32, an increase in the maximum outer diameter of the rolling bearing 1 with the seal 7 attached can be suppressed. .
Therefore, a more compact rolling bearing can be realized.

  FIG. 6 is a view showing the outer ring housing member 8 in a state where the rolling bearing 1 is housed in a fixed manner. The outer ring housing member 8 constitutes a part of a product to which the rolling bearing 1 is assembled. Examples of the outer ring housing member 8 include a metal claw, a synthetic jelly-made product, a rubber housing, a roller, and a pulley (for example, a pulley main body of a bicycle rear transmission).

As shown in FIG. 6, a portion adjacent to the base portion 71 in the outer periphery of the fitting portion 73 of the seal 7 is referred to as a shoulder portion 79. The shoulder 79 constitutes a substantially cylindrical outer surface that is substantially orthogonal to the base 71. An annular protrusion 78 is provided on the outer periphery of the fitting portion 73 of the seal 7 adjacent to the shoulder portion 79.
In other words, the annular protrusion 78 is provided between the end surface 77 of the fitting portion 73 and the shoulder 79 in the outer periphery of the fitting portion 73 of the seal 7.

  The annular projection 78 is formed on the opposite side of the inclined portion 78a and an inclined portion 78a formed by a substantially conical surface that retreats toward the outer diameter side with respect to the fitting direction when the seal 7 is fitted into the outer ring housing member 8. A stepped portion 78 b is provided following the shoulder portion 79. The stepped portion 78 b is a perforated disk-like surface that is substantially parallel to the base 71 of the seal 7. The maximum diameter portion of the inclined portion 78 a and the maximum diameter portion of the stepped portion 78 b are connected to form a top portion 78 c of the annular protrusion 78.

  A pair of annular grooves 83 are provided on the cylindrical inner surface of the outer ring housing member 8. In the example shown in FIG. 6, the cylindrical inner surface of the outer ring housing member 8 faces the small diameter portion 81 provided at a position facing the large diameter portion 33 of the outer ring 3 of the rolling bearing 1 and the shoulder portion 79 of the seal 7. And a pair of large-diameter portions 82 provided at positions. The annular groove 83 is provided at a position between the small diameter portion 81 and the large diameter portion 82 and facing the annular protrusion 78 of the seal 7.

  The annular groove 83 includes an inclined portion 83a, a step portion 83b, and a bottom portion 83c provided at positions facing the inclined portion 78a, the stepped portion 78b, and the top portion 78c of the fitting portion 73 of the seal 7, respectively.

  The inner diameter of the small diameter portion 81 of the outer ring housing member 8 is configured to be slightly larger or substantially the same as the outer diameter of the large diameter portion 33 of the outer ring 3 of the rolling bearing 1. The inner diameter of the large-diameter portion 82 of the outer ring housing member 8 is configured to be slightly larger or substantially the same as the maximum diameter of the shoulder 79 of the fitting portion 73 of the rolling bearing 1. The inner diameter of the bottom portion 83 c of the outer ring housing member 8 is configured to be slightly larger or substantially the same as the outer diameter of the top portion 78 c of the annular protrusion 78 of the fitting portion 73 of the rolling bearing 1.

  Further, the outer diameter of the top portion 78 c of the annular protrusion 78 of the fitting portion 73 of the seal 7 is configured to be larger than the inner diameter of the large diameter portion 82 of the outer ring housing member 8.

  The method of assembling the rolling bearing 1 to the outer ring housing member 8 is not particularly limited. In the example of FIG. 6, for example, first, the rolling bearing 1 before the seal 7 is mounted is inserted into the inner circumference of the outer ring housing member 8. Then, the large-diameter portion 33 of the outer ring 3 is set so as to be opposed to the small-diameter portion 81 of the outer ring housing member 8. At this time, by adjusting the dimensional relationship between the outer diameter of the large-diameter portion 33 of the outer ring 3 and the inner diameter of the small-diameter portion 81 of the outer ring housing member 8, a stronger fit or a weaker fit can be obtained as desired. can do.

  Thereafter, the seal 7 is fitted into the outer ring 3 in the same procedure as in the case of FIG. When fitted, since the outer diameter of the top portion 78c of the annular projection 78 of the seal 7 is larger than the inner diameter of the large diameter portion 82 of the outer ring housing member 8, the annular projection 78 of the seal 7 constituted by the rubber-like elastic body 76 is deformed. While (crushing), it passes through the large-diameter portion 82 of the outer ring housing member 8 and reaches the annular groove 83 to be elastically restored.

  Since the stepped portion 78b of the annular protrusion 78 of the seal 7 and the stepped portion 83b of the annular groove 83 of the outer ring accommodating member 8 are in contact with each other in the restored state, the seal 7 is fixed to the outer ring accommodating member 8. . In this way, the rolling bearing 1 can be assembled to the outer ring housing member 8 via the seal 7.

  In this way, by forcibly fitting the annular projection 78 of the seal 7 into the annular groove 83 of the outer ring housing member 8, the coupling force between the seal 7 and the outer ring housing member 8 can be strengthened, and rolling The coupling force between the bearing 1 and the outer ring housing member 8 can be strengthened.

  Further, since the stepped portion 78b of the annular protrusion 78 of the seal 7 and the stepped portion 83b of the annular groove 83 of the outer ring accommodating member 8 are in contact with the rolling bearing 1 assembled to the outer ring accommodating member 8, the outer ring 3 Intrusion of water and mud from the outer peripheral side can be prevented, and the rust prevention effect can be improved.

  FIG. 7 is a cross-sectional view showing a composite part composed of the rolling bearing 1 and the outer ring housing member 9 obtained by insert molding. In this case, injection molding or the like is performed using the rolling bearing 1 with the seal 7 shown in FIG. 4 as an insert.

  By performing insert molding in this way, a cylindrical inner surface 94 is formed in a portion of the outer ring housing member 9 that faces the outer periphery of the rolling bearing 1 that has been fitted with the seal 7, and faces the annular protrusion 78 of the seal 7. An annular groove 93 is formed in the portion.

  As with the outer ring housing member 8, the outer ring housing member 9 constitutes a part of a product to which the rolling bearing 1 is assembled. Examples of the outer ring housing member 9 include a housing, a roller, and a pulley (for example, a pulley body of a bicycle rear transmission) made of a moldable material such as a synthetic resin or rubber.

  In the example shown in FIG. 7, the small diameter portion 95 of the outer ring housing member 9 is formed at a position slightly closer to the inner periphery than the outer periphery of the base portion 71 of the seal 7. Therefore, the large-diameter portion 33 of the outer ring 3 and the entire fitting portion 73 including the annular protrusion 78 of the seal 7 and the portion reaching the outer periphery of the base portion 71 are completely covered by the outer ring housing member 9 along its shape. ing.

  With this configuration, the coupling force between the seal 7 and the outer ring housing member 9 can be made stronger, and thus the coupling force between the rolling bearing 1 and the outer ring housing member 9 can be further strengthened. .

  As a result, the intrusion of water and mud from the outer periphery of the outer ring 3 can be completely prevented, and the rust prevention effect can be further ensured.

  The material and surface treatment of the outer ring 3 described above are not particularly limited. For example, stainless steel may be used, but in each of the above embodiments, bearing steel (SUJ2 or the like) is used and the surface treatment is performed. Absent. Even in this configuration, as described above, the seal 7 formed so as to continuously cover the side surface 31 of the outer ring 3 and the entire chamfered portion 38 where rust is most likely to occur from the side surface 31 of the outer ring 3 to the outer periphery. Can be completely covered. As a result, a high rust prevention effect can be obtained without using expensive stainless steel.

  Further, the material and surface treatment of the inner ring 2 are not particularly limited. For example, stainless steel may be used. In each of the above embodiments, bearing steel (SUJ2 or the like) is used, and the surface treatment is performed after galvanization. Chromate treatment is applied. The content of the chromate treatment is not particularly limited, but a colored chromate treatment or a trivalent chromate treatment is preferable from the viewpoint of the rust prevention effect, and a trivalent chromate treatment is more preferable from the viewpoint of environmental protection.

  Even when configured in this manner, when the rolling bearing 1 is assembled to a product, the inner ring 2 is generally not visible from the outside, so that the appearance of the product is not impaired. Moreover, a high rust prevention effect can be obtained without using expensive stainless steel.

Further, the material of the rubber-like elastic body 76 of the seal 7 is not particularly limited, but a material having excellent tensile strength, wear resistance, and oil resistance, having a small amount of compression set and an appropriate elasticity is preferable.
In each of the above embodiments, nitrile rubber (NBR) is used as the rubber-like elastic body 76.

  In addition, the manufacturing method of the seal 7 is not particularly limited. In each of the above embodiments, first, an iron plate is press-molded to obtain a cored bar 75, which is appropriately subjected to surface treatment, and then the cored bar 75. The seal 7 is obtained by so-called insert molding, in which the rubber-like elastic body 76 is molded using as an insert product.

In each of the above embodiments, a cage made of a synthetic resin as shown in FIG. 4 is used from the viewpoint of weight reduction, cost, etc., but the material and shape of the cage 6 are not particularly limited. Absent.
For example, various shapes made of synthetic resin or metal can be used. The present invention can also be applied to a rolling bearing that does not use a cage.

  Moreover, in each said embodiment, although the steel ball 5 was demonstrated to the example as a rolling element, a rolling element is not limited to a steel ball, Metal balls other than steel may be sufficient. Further, non-metallic balls such as synthetic resin, ceramic, and glass may be used. Further, instead of a sphere, a cylindrical shape or a truncated cone shape may be used. If it is possible to use a non-metallic rolling element in terms of strength and cost, it is more convenient from the viewpoint of rust prevention.

Although the present invention has been described above as a preferred embodiment, the terminology has been used for description rather than limitation and departs from the scope and spirit of the present invention. Without departing from the scope of the appended claims. Also, while the above describes only some exemplary embodiments of the present invention in detail, those skilled in the art will recognize the exemplary implementations described above without departing from the novel teachings and advantages of the present invention. It will be readily appreciated that many variations in form are possible. Accordingly, all such modifications are intended to be included within the scope of the present invention.
That is, in the above-described embodiment, the description has been made with the configuration in which both ends of the annular space 4 are closed by the pair of seals 7, but depending on the combination with other parts, water and dust beach can be prevented from entering from the outside. In that case, it is only necessary to have a configuration in which one end of the annular space 4 is closed with the seal 7, and this is included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Rolling bearing 3 Outer ring 4 Annular space 5 Steel ball 6 Cage 7 Seal 31 Side surface 38 Chamfered portion 71 Base 73 Fit-in portion

Claims (6)

A rolling bearing comprising an inner ring, an outer ring, a plurality of rolling elements arranged in an annular space between the inner ring and the outer ring, and a seal that closes an end of the annular space,
The seal
A substantially disk-shaped base with a hole in the center;
An annular lip extending on the inner peripheral side of the base, and a lip that can rotate relative to the inner ring while elastically contacting the outer peripheral side of the inner ring;
A rolling bearing comprising: a substantially cylindrical fitting portion extending on the outer peripheral side of the base portion; and a fitting portion fitted on the outer peripheral side of the outer ring and fixed to the outer ring. The rolling bearing according to claim 1,
The seal
A metal cored bar integrally formed from the base part to the fitting part;
A rubber-like elastic body formed in close contact with the core metal so that the core metal is not exposed to the outside of the bearing when the seal is mounted on the rolling bearing;
It is characterized by. The rolling bearing according to claim 1 or 2,
The seal
An annular protrusion provided on the outer periphery of the fitting portion, the annular protrusion being fitted into an annular groove on the cylindrical inner surface of the outer ring housing member that fixedly houses the outer ring of the rolling bearing;
It is characterized by. A seal for closing an end of the annular space of a rolling bearing provided with an inner ring, an outer ring, and a plurality of rolling elements arranged in an annular space between the inner ring and the outer ring,
A substantially disk-shaped base with a hole in the center;
An annular lip extending on the inner peripheral side of the base, and a lip that can rotate relative to the inner ring while elastically contacting the outer peripheral side of the inner ring;
_A substantially cylindrical inset extending on the outer peripheral side of the base, and an inset fitted into the outer ring of the outer ring and fixed to the outer ring,
Having
Rolling bearing seal characterized by The rolling bearing seal according to claim 4,
A metal cored bar integrally formed from the base part to the fitting part;
A rubber-like elastic body formed in close contact with the metal core so that the metal core is not exposed to the outside of the bearing with the seal mounted on the rolling bearing;
Having
It is characterized by. The rolling bearing seal according to claim 4 or 5,
An annular protrusion provided on the outer periphery of the fitting portion, the annular protrusion being fitted into an annular groove on the cylindrical inner surface of the outer ring housing member that fixedly houses the outer ring of the rolling bearing;
It is characterized by.

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