WO2015152329A1

WO2015152329A1 - Rolling bearing with filter

Info

Publication number: WO2015152329A1
Application number: PCT/JP2015/060341
Authority: WO
Inventors: 清茂山内
Original assignee: Ntn株式会社
Priority date: 2014-04-04
Filing date: 2015-04-01
Publication date: 2015-10-08

Abstract

　To reliably prevent impurities in lubricating oil from infiltrating a bearing, and to improve the reliability and extend the service life of a seal device in a rolling bearing with a filter. A seal device (20) has a configuration in which a ring member (21), comprising a metal ring formed integrally with a filter (22) that allows lubricating oil to pass through and restricts the passage of solid impurities, is fitted in either an outer bearing ring (1) or an inner bearing ring (2), and a lip part (23), comprising an elastomer material bonded to the ring member (21), faces the other bearing ring. An auxiliary ring member (24) is fitted in the other bearing ring, the auxiliary ring member (24) being made to face the lip part (23) to form a labyrinth structure.

Description

Rolling bearing with filter

This invention relates to an oil-lubricated rolling bearing, and more particularly to a filter-equipped rolling bearing that is lubricated with oil flowing in through a filter provided in order to prevent entry of foreign matter in the lubricating oil.

Rolling bearings are incorporated in various parts of various industrial equipment such as automobiles and other transportation equipment, power transmission mechanisms and traveling devices for construction machines, hydraulic pumps, and other various industrial machines.

In rolling bearings, there are contact points between the rolling elements and the inner and outer raceways inside the bearing, which is the space between the inner and outer races. It is required to continuously supply lubricating oil inside the bearing. A seal ring is attached to the race ring in order to suppress the situation where the lubricant oil leaks to the outside of the bearing. Conventionally, oil bath lubrication has been used as a method of supplying lubricating oil into the bearing. In oil bath lubrication, foreign matters such as metal wear powder and peeling pieces can be mixed with the lubricating oil stored outside the bearing. As a bearing usage environment in which such a situation may occur, for example, a bearing device in a hydraulic pump such as the above-described various construction machines can be cited.

As described above, foreign matter such as gear wear powder (iron powder, etc.) may be mixed in the oil that lubricates the rolling bearing. If foreign matter enters the inside of the rolling bearing, the raceway surface and the rolling surface are peeled off due to the biting of the foreign matter, thereby reducing the durability of the rolling bearing.

For this reason, a rolling bearing with a filter in which a filter is provided in a seal ring attached to the rolling bearing has been proposed in order to prevent the entry of foreign matter. In this rolling bearing with a filter, a filter for capturing foreign matter is attached to an oil passage hole for oil circulation provided in a seal ring.

For example, the following Patent Document 1 discloses a technique in which an opening is provided in a seal ring made of an elastomer material (hereinafter referred to as “elastic seal member”) and the opening is covered with a filter. The elastic seal member is directly attached to either the inner or outer ring of the bearing. A seal lip provided on the elastic seal member is in contact with the opposite raceway.

JP-A-6-323335 (see page 5, Fig. 1-3)

In the rolling bearing with filter described in the above-mentioned Patent Document 1, an elastic seal member made of an elastomer material is mounted on the bearing opening (seal mounting portion) so as to be exposed. For this reason, when some external force is applied to the elastic seal member at the time of assembling the bearing, at the time of conveyance, or when incorporating the mechanical device, the elastic seal member is deformed or deviated from the normal built-in state, so that the sealing performance is impaired. there is a possibility.

¡In order not to impair the sealing performance, it is necessary to accurately control the interference between the elastic seal member and the bearing. However, since the elastic seal member is directly attached to the bearing, it is necessary to accurately manage the dimensions of the elastic seal member and the bearing in order to improve the accuracy of the tightening allowance. This causes an increase in manufacturing cost. In particular, there is a technical limit in dimensional management of the elastic seal member that is a molded product. On the other hand, if the tightening margin is increased in order to ensure the sealing property, the torque of the bearing is increased and the temperature is increased.

Further, in the rolling bearing with filter described in Patent Document 1, the seal lip is in contact with the raceway opposite to the raceway to which the elastic seal member is fixed. For this reason, when the bearing is used at high speed rotation, the torque of the bearing is increased, the temperature is increased, and the seal lip is prematurely worn.

Accordingly, a first object of the present invention is to reliably prevent foreign matters in the lubricating oil from entering the bearing, and to improve the reliability and extend the life of the seal device in the rolling bearing with a filter. .

Further, the seal ring of Patent Document 1 employs a mesh-like filter member, but does not specifically disclose the mesh shape or mesh size.

The inventor of the present application examined the form of the filter provided in the seal ring by experiment. In a simple planar mesh filter, the filter is clogged with foreign matter in the lubricating oil, and the lubricating oil is supplied into the bearing. It has been found that this leads to a decrease in bearing life and an increase in temperature. In addition, if the size of the eye is increased to roughen the filter in order to prevent clogging, the foreign matter catching performance is reduced, and foreign matter can easily enter the bearing, leading to a reduction in bearing life. I also understood that.

Therefore, the second problem of the present invention is to prevent clogging without roughening the filter provided in the seal ring.

In order to solve the first problem, the present invention incorporates a rolling element between an outer race and an inner race, and at least a bearing space formed between the outer race and the inner race. In a rolling bearing with a filter in which an opening at one end is covered with a sealing device and foreign matter contained in the lubricating oil is captured by a filter provided in the sealing device, the sealing device is capable of passing the solid foreign matter through which the lubricating oil can pass. A ring member integrally formed with a restricting filter is attached to one of the outer race ring or the inner race ring, and a lip portion made of a material softer than the ring member joined to the ring member, It was set as the structure provided with the rolling bearing with a filter facing the other bearing ring.

By joining a lip part made of a relatively soft material to a ring member with an integral filter, the ring member can be securely attached to one of the races and maintain the function of the filter over a long period of time. The lip portion can maintain a good sealing function with the other raceway.

Here, for example, an elastomer material can be used as the material of the lip portion. At this time, the ring member employs a material harder than the elastomer material of the lip portion. The material of the ring member is preferably a material other than the elastomer material, and for example, a metal, a resin, or the like can be used. An elastomer material having a relatively high rigidity can be used as a material for the ring member as long as it is harder than the material for the lip portion.

In the conventional rolling bearing with a filter, the elastomer material constituting the main body of the sealing device is directly fixed to the bearing ring of the bearing. According to this configuration, a relatively hard ring member is attached to one of the bearing rings. The soft lip is not fixed directly to the race. For this reason, it is not necessary to strictly manage the dimensions of a soft material such as an elastomer material and the dimensions of bearing parts such as a race ring and a rolling element as in the past.
Also, the ring member is more resistant to deformation due to external force than the material of the lip part, and is harmful to the bearing even in bearings used in harsh environments where foreign matter may enter the lubricating oil. It is possible to reliably prevent a foreign matter from entering the inside of the bearing over a long period of time, and to extend the life of the bearing.

In this configuration, an auxiliary ring member is mounted on the other race ring, the auxiliary ring member is opposed to the lip portion of the ring member, and a labyrinth structure is formed between the auxiliary ring member and the ring member Can be adopted.

If a labyrinth structure is adopted, a predetermined sealing effect can be obtained while there is no contact between the rotating side and the stationary side. For this reason, the lifetime of a ring member or a lip | rip part can be extended.

In these configurations, when the relative rotation around the axis of the outer raceway and the inner raceway is stopped or when the rotation is performed at a low speed, the lip portion contacts the other raceway or a member fixed to the other raceway. Further, it is possible to adopt a configuration in which the lip portion is set so as not to contact the other race ring or a member fixed to the other race ring during high-speed rotation.

That is, as described above, since the lip portion made of a relatively soft material is joined to the ring member integrally provided with the filter, the lip portion is attached to the ring member when the bearing is stopped and when rotating at a low speed. Intrusion of foreign matter can be prevented by contacting the opposite side raceway and the member (for example, the auxiliary ring member) attached to the raceway.

Also, during high-speed rotation of the bearing, due to the difference in the amount of thermal expansion between the lip portion with different materials and different linear expansion coefficients, and the opposite raceway ring and the member attached to the raceway ring, It can be set so that a gap is generated between the side raceway ring and the member attached to the raceway ring. This can prevent an increase in bearing torque, an increase in bearing temperature, and excessive wear of the soft material of the lip portion.

The clearance between the two members that occurs during high-speed rotation, that is, the clearance between the lip and the bearing ring on the opposite side or the member attached to the bearing ring, is set to be smaller than the size of foreign matter that adversely affects the bearing life. By doing so, it is possible to more reliably prevent a decrease in bearing life. The setting of the clearance between the two members that occurs during high-speed rotation can be calculated using the temperature rise amount and the linear expansion coefficient of the two members.

In each of these configurations, it is possible to employ a configuration in which the ring member is mounted on a stationary raceway of the inner raceway or the outer raceway. At this time, when the auxiliary ring member is used, the auxiliary ring member is attached to the raceway on the rotation side.

By attaching a ring member equipped with a filter through which lubricating oil is passed to the bearing ring (fixed ring) on the stationary side of the bearing, the filter does not rotate, preventing a decrease in the oil permeability of the lubricating oil accompanying the rotation of the bearing. can do. The filter is preferably stationary.

For example, when the inner race is on the rotation side and the outer race is on the stationary side, the ring member is preferably attached to the outer race. On the contrary, when the inner race is stationary and the outer race is rotation, the ring member is preferably attached to the inner race.

Further, the filter may be formed on the entire surface of the ring member, but it is possible to adopt a configuration formed on at least a portion excluding the fitting surface to the one raceway ring.

In addition, the ring member adopts a configuration that is, for example, a metal ring that configures the filter by a large number of holes formed by pressing, or a synthetic resin ring that configures the filter by a large number of holes formed by injection molding. can do.

部材 By using a metal ring with a large number of holes for the ring member, it is possible to easily manufacture a member that is resistant to deformation against an external force compared to a lip portion made of a soft material such as an elastomer material. As the metal ring having a large number of holes, for example, a punching metal can be used.

In addition, by adopting a labyrinth structure in a non-contact state between the two ring members of the ring member and the auxiliary ring member, it is possible to allow the circulation of lubricating oil inside and outside the bearing to some extent while ensuring sealing performance. An excessive temperature rise can be prevented. In addition, although a filter may be formed also in an auxiliary | assistant ring member, the filter does not necessarily need to be formed in the auxiliary | assistant ring member. In other words, the metal ring, synthetic resin ring, or other member made of a material used as the auxiliary ring member may not necessarily have a hole.

In order to solve the second problem, in the present invention, in each of the above configurations, the filter is formed by a plurality of filtering holes that are passed through the ring member, and is formed in the ring member. Of the surfaces on the outer side of the bearing, it is possible to adopt a configuration in which a hole surrounding portion surrounding the filtration hole protrudes toward the outside of the bearing.

In this way, if the filter is formed by a plurality of filter holes passed through the ring member, the vicinity of the filter hole inlet (that is, the filter eye) is three-dimensionally formed by the surface of the ring member on the bearing outer side. Is possible. Here, if a three-dimensional shape with the hole surrounding the filter hole protruding toward the outside of the bearing is adopted, the foreign object is filtered when the foreign substance mixed with the lubricating oil cannot pass through the inlet of the filter hole. Without entering the hole, it is caught by the periphery of the hole and captured by the filter, and then flows to the outside of the bearing. In addition, some foreign matters directed to the surface portion other than the peripheral portion of the hole of the ring member may be caused to flow toward the filter hole by the lubricating oil flowing along the surface portion. This foreign matter cannot be directed to the inlet of the filtration hole by being obstructed by the hole peripheral portion protruding toward the outside of the bearing. Thus, clogging can be prevented without roughening the filter.

Preferably, the hole peripheral portion protrudes in a tapered shape toward the outside of the bearing. If the hole periphery protrudes in a tapered shape toward the outside of the bearing, the trapped foreign matter is inclined by the taper shape, and it is easier to come off to the side from the inlet of the filtration hole. It is difficult to stay in the state of closing the entrance. The tapered shape may be any shape such as a cone, a triangular cone, a square cone, or the like, in which foreign matter does not easily stay, but a tapered shape is more preferable in order to make it easier to come off from the inlet of the filtration hole.

The inner diameter of the minimum hole diameter portion of the filter hole of the filter formed in the ring member is preferably 0.3 mm to 0.7 mm.

It is also preferable that the inside of the filtration hole has a taper shape that becomes wider from the bearing outer side toward the inner side. When such a filtering hole is used, the foreign matter that has passed through the inlet is less likely to be clogged in the hole.

Further, in the configuration provided with the auxiliary ring member, a configuration having an outer peripheral portion protruding toward the outside of the bearing so as to cause a flow that hinders the approach of the lubricating oil to the filter with the rotation. Can be adopted.

The auxiliary ring member attached to the other race ring is arranged near the ring member in order to form a labyrinth seal with the ring member attached to the one race ring. Therefore, as the other raceway rotates with respect to the one raceway, the auxiliary ring member attached to the other raceway rotates near the ring member. When the lubricating oil comes into contact with the rotating auxiliary ring member, it receives a feeding action by centrifugal force near the ring member. If the auxiliary ring member has an outer peripheral portion protruding toward the outside of the bearing, the lubricating oil sent by centrifugal force can be directed away from the ring member. If the flow of the lubricating oil interferes with the filter in such a flow, the foreign matter mixed in the lubricating oil is hardly pushed into the eyes of the filter. For this reason, clogging can be prevented without roughening the filter.

Further, it is possible to adopt a configuration in which the auxiliary ring member has a blade portion that causes a vortex of the lubricating oil in contact with the filter on the outer side of the bearing as the other raceway ring rotates.

If the wing part is formed on the auxiliary ring member, the lubricating oil can be agitated near the filter outside the bearing with the rotation of the wing, and this can cause a vortex of the lubricating oil in contact with the filter. This vortex has the effect of allowing foreign matter to flow from the eyes of the filter. For this reason, clogging can be prevented without roughening the filter.

In each of these configurations, a configuration is adopted in which the filter is formed only within the half circumference region of the ring member.

According to this configuration, when oil-lubricated in a manner in which the sealed rolling bearing is immersed in the oil bath, the bearing can be installed with the half circumference area of the ring member without a filter as the lower side. Generally, when lubricating oil is stored in an external oil bath, foreign matter stays below the oil bath. Therefore, if the half-circumference region without the filter is set to the lower side as described above, lubricating oil with relatively little foreign matter can be supplied into the bearing via the filter positioned on the upper side of the ring member. For this reason, it is possible to prevent clogging of the filter without increasing the filter eye size.

In the present invention, a ring member that is integrally provided with a filter is joined to a lip portion made of a relatively soft material such as an elastomer material. Can be maintained over a long period of time, and the lip portion can maintain the sealing function well with respect to the other raceway.

Also, a relatively hard ring member is attached to one of the races, and the soft lip is not directly fixed to the race. For this reason, it is not necessary to strictly manage the dimensions of a soft material such as an elastomer material and the dimensions of bearing parts such as a race ring and a rolling element as in the past. Also, the ring member is more resistant to deformation due to external force than the material of the lip part, and is harmful to the bearing even in bearings used in harsh environments where foreign matter may enter the lubricating oil. It is possible to reliably prevent a foreign matter from entering the inside of the bearing over a long period of time, and to extend the life of the bearing.

Further, the filter is formed by a plurality of filtration holes passed through the ring member, and the hole peripheral portion surrounding the filtration hole is protruded toward the outside of the bearing among the surfaces of the ring member on the bearing outer side. Therefore, clogging can be prevented without roughening the filter provided in the seal ring.

The principal part expanded sectional view which shows 1st embodiment of this invention The perspective view of the sealing device of the embodiment The principal part expanded sectional view which shows 2nd embodiment (A) and (b) are principal part expanded sectional views which show 3rd embodiment. FIG. 3 is a perspective view of a sealing device according to a third embodiment. (A) (b) is a principal part expanded sectional view which shows the example of the mounting method of the sealing device to a bearing (A) (b) is a principal part expanded sectional view which shows the example of the mounting method of the sealing device to a bearing The ring member of a sealing device is shown, (a) is a principal part expanded sectional view, (b) is a right view of (a). The raw material at the time of manufacturing the ring member of a sealing device is shown, (a) (b) is a general view, (c) is the principal part enlarged view of (a) (b). Chart showing the relationship between the inner diameter of the seal lip (the inner diameter of the lip), the outer diameter of the inner ring, and the tightening margin (A) is a graph showing the relationship between the size of the indentation and the life reduction rate, and (b) is a graph showing the relationship between the size of the filter mesh and the size of the indentation. Sectional drawing which shows the principal part of 4th embodiment of the invention which concerns on this application The partial side view which shows the filtration hole vicinity in the bearing outer side surface of the seal ring which concerns on 4th embodiment Enlarged sectional view of the vicinity of the filtration hole according to the fourth embodiment Side view showing filter hole arrangement in seal ring according to fourth embodiment from outside of bearing Sectional drawing which shows the principal part of 5th embodiment of the invention which concerns on this application Sectional drawing which shows the principal part of 6th embodiment of the invention which concerns on this application The side view which shows the wing | blade part arrangement | positioning in the annular member which concerns on 6th embodiment from the bearing outer side Sectional drawing which shows the principal part of 7th embodiment of the invention which concerns on this application

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an enlarged cross-sectional view of a main part of a rolling bearing A according to a first embodiment of the present invention. In this embodiment, a tapered roller bearing used for a hydraulic pump is assumed as the rolling bearing A.

As shown in FIG. 1, the rolling bearing A has a configuration in which the raceway surfaces 4 and 5 of the outer raceway (outer ring) 1 that is one raceway and the inner raceway (inner race) 2 that is the other raceway are formed. In the middle, a tapered roller is incorporated as the rolling element 3. The rolling element 3 is held in the circumferential direction by a cage 6.

The raceway surface 5 of the inner raceway ring 2 and the raceway surface 4 of the outer raceway ring 1 are provided so that the distance from each other decreases from one axial direction side on the right side in the drawing toward the other axial direction side on the left side in the drawing. ing. Correspondingly, the rolling surface of the tapered roller as the rolling element 3 is also provided so that its diameter narrows from the one axial side to the other axial side.

The inner race 2 is provided with a large flange portion 2b that protrudes toward the outer diameter side on one side in the axial direction and a small flange portion 2c that protrudes toward the outer diameter side on the other side in the axial direction. The rolling element 3 is disposed between the large collar part 2b and the small collar part 2c.

In this embodiment, the outer race 1 is mounted on a non-rotating fixed housing (not shown) and cannot rotate. Further, the inner race 2 is mounted so as to rotate integrally with a rotation shaft (not shown) that can rotate around the axis. That is, the outer race 1 is a stationary race and the inner race 2 is a rotation race.

The seal device 20 is attached to the rolling bearing A. As shown in FIG. 1, the seal device 20 is attached so as to cover an opening on one side in the axial direction in the bearing space of the rolling bearing A, that is, on the large collar portion 2 b side of the inner race 2.

If necessary, a similar sealing device 20 may be attached to the opening on the other side in the axial direction. At this time, it is necessary to secure a space for the seal mounting portion in the bearing opening portion on the small flange portion 2c side of the inner race 2 so that the seal device 20 does not interfere with the cage 6 and the rolling element 3.

The sealing device 20 includes a ring member 21 integrally formed with a filter 22 through which lubricating oil can pass and restricts the passage of solid foreign matters, and a lip portion 23 made of a material softer than the ring member 21 joined to the ring member 21. Is provided.

In this embodiment, rubber, that is, an elastomer material is used as the material of the lip portion 23. The ring member 21 is made of a metal such as stainless steel. That is, a material harder than the elastomer material of the lip portion 23 is employed for the ring member 21. As a material of the ring member 21, a metal other than stainless steel, for example, a cold-rolled steel plate such as SPCC that is easy to process may be used, or an elastomer material that is harder than the lip 23 or a lip A synthetic resin harder than the portion 23, in particular, a hard resin can be employed.

As shown in FIG. 2, the ring member 21 includes a cylindrical locking portion 21 a along the inner diameter surface of the outer raceway ring 1, and an axially outer end edge of the locking portion 21 a toward the inner raceway ring 2 side. And a wall portion 21b that rises over the entire circumference.

An annular lip portion 23 is joined to the tip 21c of the wall portion 21b. In this embodiment, the front end 21c of the annular wall portion 21b is fitted into the fitting groove provided on the lip portion 23 over the entire circumferential direction, and the lip portion 23 is fixed to the wall portion 21b. The fixing structure of the lip portion 23 to the portion 21b may have another form. For example, the above-described fitting fixing and an adhesive may be used in combination, or vulcanization adhesion or both members may be fixed only by an adhesive regardless of the fitting fixing.

At the inner end in the axial direction of the locking portion 21a, a guide portion 21d that bends or curves toward the inner race 2 that is the opposite race is provided. By providing the guide portion 21d, the ring member 21 can be easily inserted into the outer race 1.

The method of inserting the ring member 21 into the outer race 1 is shown in FIGS. The ring member 21 is disposed so that the locking portion 21a faces the bearing side, and is inserted into the opening so as to cover the annular opening between the outer raceway ring 1 and the inner raceway ring 2. At this time, it is convenient to use the insertion jig T. The insertion jig T may be a rod-shaped member that pushes a part of the ring member 21 in the circumferential direction, or may be an annular member that pushes the entire circumference of the ring member 21 in the circumferential direction.

The filter 22 includes a large number of holes 22 a provided in the wall portion 21 b of the ring member 21. Although the hole 22a should just be provided in the wall part 21b at least, in addition to that, you may be provided in other site | parts, such as the latching | locking part 21a.

The ring member 21 is press-fitted into the bearing space so that the locking portion 21 a is along the inner diameter surface of the outer race 1, and the ring member 21 is mounted inside the outer race 1. The tip 23 a of the lip portion 23 faces the outer diameter surface of the inner race 2. In this embodiment, the tip 23 a of the lip portion 23 is tapered and faces the outer diameter surface of the large collar portion 2 b of the inner race 2. Further, the cross section of the lip portion 23 extends from the attachment portion to the wall portion 21b toward the axial center of the bearing over the entire circumference in a direction orthogonal to the axial direction, and the tip 23a side is bent slightly outward in the axial direction. It becomes the shape to do.

By joining a lip portion 23 made of an elastomer material, which is a relatively soft material, to the ring member 21 integrally provided with the filter 22, the ring member 21 is firmly attached to the raceway so that the function of the filter 22 is achieved. Can be maintained over a long period of time, and the lip portion 23 can maintain a good contact pressure with respect to the raceway on the opposite side, and can maintain its function over a long period of time.

In addition, since the relatively hard ring member 21 is mounted on the raceway and the soft lip portion 23 is not directly fixed to the raceway, the dimensions of the soft material such as an elastomer material and the dimensions of the bearing parts such as the race and rolling elements are included. There is an advantage that it is not necessary to strictly manage them. Further, the ring member 21 is more resistant to deformation due to external force than the material of the lip portion 23, can maintain the function of the filter 22 over a long period of time, and can extend the life of the bearing.

FIG. 3 shows a second embodiment of the present invention. In the second embodiment, an auxiliary ring member 24 is attached to a raceway on the opposite side of the raceway ring to which the ring member 21 is attached. Here, the ring member 21 is attached to the outer raceway 1 on the stationary side, and the auxiliary ring member 24 is attached to the inner raceway 2 on the rotation side.

The auxiliary ring member 24 is opposed to the lip portion 23 joined to the ring member 21, and a labyrinth structure (labyrinth seal structure) in which a minute gap is bent is formed between the auxiliary ring member 24 and the ring member 21. . Since the labyrinth structure is adopted, a predetermined sealing effect is ensured while making no contact between the rotating side and the stationary side. That is, in this embodiment, a labyrinth structure in which a minute gap is bent is adopted as the seal structure, so that the lubricating oil seals the inside and outside of the bearing space by resistance when passing through the bent minute gap. be able to.

In the second embodiment, the ring member 21 includes a cylindrical locking portion 21a along the inner diameter surface of the outer race ring 1, and the inner race ring 2 side from the axially outer end edge of the lock portion 21a. And a wall portion 21b that rises over the entire circumference. Further, the wall portion 21 b includes a cylindrical relief portion 21 e that extends inward in the axial direction at a portion closer to the inner diameter than the filter 22. By providing the relief portion 21e in the middle of the wall portion 21b, the tip 21c of the wall portion 21b is positioned on the inner side in the axial direction of the bearing than the position of the filter 22.

Further, an annular lip portion 23 is joined to the tip 21c of the wall portion 21b. The cross section of the lip portion 23 is a member that extends in a direction orthogonal to the axial direction from the attachment portion to the wall portion 21b toward the axial center of the bearing over the entire circumference, as in the first embodiment, A shape in which the tip 23a side is slightly bent outward in the axial direction may be adopted. In addition, the joining method of the lip part 23 to the ring member 21 is the same as that of the above-mentioned embodiment.

The auxiliary ring member 24 has a cylindrical locking portion 24a along the outer diameter surface of the inner raceway ring 2 and the entire circumference from the axial outer end edge of the locking portion 24a toward the outer raceway ring 1 side. It is a member having an L-shaped cross section including a wall portion 24b that rises.

The labyrinth structure includes a lip portion 23 and a locking portion 24a of the auxiliary ring member 24, a wall portion 24b of the lip portion 23 and the auxiliary ring member 24, a wall portion 21b (including the escape portion 21e) of the ring member 21, and the auxiliary ring member 24. It is formed by each minute gap between the wall portion 24b.

A method for inserting the ring member 21 into the outer race 1 is shown in FIGS. The ring member 21 is arranged so that the locking part 21a faces the bearing side, and the auxiliary ring member 24 is arranged so that the locking part 24a faces the bearing side. The ring member 21 and the auxiliary ring member 24 are inserted into the openings so as to cover the annular opening between the outer race ring 1 and the inner race ring 2. At this time, the insertion jig T to be used is the same as in the first embodiment described above.

3rd Embodiment of this invention is shown to Fig.4 (a) (b) and FIG. In this embodiment, the shape of the escape portion 21e of the ring member 21 of the second embodiment is changed.

The ring member 21 has a cylindrical locking portion 21a along the inner diameter surface of the outer race 1, and a wall that rises from the axially outer end edge of the locking portion 21a over the entire circumference toward the inner race 2 side. Part 21b. Further, the wall portion 21 b includes a conical relief portion 21 e extending in an axially inner side and an inner diameter direction at a portion closer to the inner diameter than the filter 22. Other configurations are the same as those of the second embodiment described above. By making the escape portion 21e conical, it is easy to mold metal or resin.

In each of the first to third embodiments, when the relative rotation around the axis between the outer race 1 and the inner race 2 is stopped or during low-speed rotation, the lip 23 is on the opposite raceway (each implementation). In the embodiment, the inner raceway ring 2) or a member (auxiliary ring member 24 in each embodiment) fixed to the raceway ring is set. Further, during high-speed rotation, the lip portion 23 is set so as not to come into contact with the facing raceway ring or a member fixed to the raceway ring.

That is, since the lip portion 23 made of an elastomer material is joined to the ring member 21 integrally provided with the filter 22, the lip portion 23 is opposite to the side on which the ring member is mounted when the bearing is stopped and when rotating at a low speed. Intrusion of foreign matter is prevented by contacting the raceway ring and the member mounted on the raceway ring. Further, at the time of high-speed rotation of the bearing, due to the difference in thermal expansion amount between the lip portion having different materials and different linear expansion coefficients, and the opposite raceway ring and the member mounted on the raceway ring, It is set so that a clearance is generated between the opposite raceway ring and a member attached to the raceway ring.

To explain this point, since the temperature of the lubricating oil is relatively low when the bearing is stopped and when rotating at a low speed, the lip portion 23 and the opposite bearing ring facing it, the auxiliary ring member 24 mounted on the bearing ring, etc. There is no significant difference in the amount of thermal expansion to the outside in the radial direction of the bearing when the member is cold. However, since the temperature of the lubricating oil becomes relatively high at the time of high-speed rotation of the bearing, the lip portion 23 has a bearing radius between the opposite raceway ring and the member such as the auxiliary ring member 24 attached to the raceway ring. This causes a difference in the amount of thermal expansion outward in the direction. Specifically, the lip portion 23 expands so as to be relatively large and expands toward the outer diameter side, and the members such as the opposite raceway ring and the auxiliary ring member 24 attached to the raceway ring are as large as the lip portion 23. Does not swell. As a result, a gap is generated between the lip portion 23 and a member facing the lip portion 23, or the initial allowance of the lip portion is reduced, increasing the bearing torque and the bearing temperature during high-speed rotation. Excessive wear of the material of the portion 23 can be prevented.

Thus, it is desirable that the material of the lip portion 23 joined to the ring member 21 has a higher coefficient of thermal expansion than the material of the ring member 21, the auxiliary ring member 24, and the race ring. Generally, metal has a lower coefficient of thermal expansion than rubber or resin, and generally hard resin has a lower coefficient of thermal expansion than rubber. For example, the ring member 21 and the auxiliary ring member 24 are made of a metal ring or a hard resin. If the resin ring and the lip portion 23 are made of an elastomer material such as rubber, such setting can be easily performed. Further, the ring member 21 and the auxiliary ring member 24 are made of a metal ring and the lip portion 23 is made of resin, or the ring member 21 and the auxiliary ring member 24 are made of a resin ring, and the lip portion 23 is made of a material of the ring member 21 and the auxiliary ring member 24. Alternatively, the difference in coefficient of thermal expansion as described above may be set as a soft resin having a high coefficient of thermal expansion.

The clearance between the two members generated at the time of high-speed rotation, that is, the clearance between the lip portion 23 and the opposite raceway ring or the member attached to the raceway ring is set to be smaller than the size of the foreign matter that adversely affects the bearing life. As a result, it is possible to more reliably prevent a decrease in bearing life. The setting of the clearance between the two members that occurs during high-speed rotation can be calculated using the temperature rise amount and the linear expansion coefficient of the two members.

As described above, the filter 22 only needs to be formed on at least one of the portions excluding the locking portion 21a that is a fitting surface to the raceway, but may be formed on the entire surface of the ring member 21. Good.

For example, in FIGS. 8A and 8B, the filter 22 is provided on a part of the wall portion 21b. A filter 22 is not provided in the locking portion 21a that is a fitting surface to the raceway. Further, the filter 22 is not provided in the attachment portion of the escape portion 21e or the lip portion 23 on the tip 21c side. Reference numeral 21f in FIGS. 8A and 8B is a fitting convex portion extending over the entire circumference in the circumferential direction. The fitting convex portion 21f enters the fitting concave portion provided on the race ring side, thereby preventing the ring member 21 from coming off. In each embodiment, such a fitting convex part 21f may be adopted.

Here, the filter 22 may be provided also on the attachment portion of the locking portion 21a, the escape portion 21e, or the lip portion 23 on the tip 21c side. The auxiliary ring member 24 does not necessarily have to be formed with the filter 22, but the filter 22 can be provided at the site as long as the sealing effect by the labyrinth structure is not hindered.

FIG. 9A shows a material R1 for manufacturing the ring member 21. FIG. A central portion of a circular metal plate made of a press-formed product in which a large number of filtration holes (holes) 22a are formed is cut into a donut shape by a circular cutting line c in the figure, and a plurality of concentric circular folds are formed. The ring member 21 is formed by bending the member at the line of sight r. FIG. 9B shows a circular metal plate material R2 made of a pressed product in which a filtration hole 22a is provided only in a portion corresponding to the wall portion 21b. Similarly, the ring member 21 is formed by bending at a plurality of concentric crease lines r. FIG. 9C is an essential part enlarged view showing an example of the hole 22a. The filter holes 22a may be provided radially around the axis as shown in FIGS. 9A and 9B, or may be arranged in a grid pattern as shown in FIG. 9C.

Thus, by using a metal ring (punched metal or the like) made of a press-processed product as the material of the ring member 21, the filter 22 can be configured by a large number of filter holes 22a formed by the press process. Alternatively, the filter 22 may be configured by a large number of filter holes 22a formed by injection molding by using the ring member 21 as a resin injection molded product.

Further, here, a perfect circular filtering hole 22a having the same inner diameter with respect to all the circumferential directions of the filtering hole 22a, such as the inner diameters d1 and d2 shown in FIG. 9C, is employed, but the inner diameters d1 and d2 are used. The shape may be oval. In addition, the shape of the filter hole 22a may be rectangular, or may be a filter 22 having a mesh structure in which filter holes 22a of various shapes are arranged vertically and horizontally.

Examples of the elastomer material used for the lip portion 23 include nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), acrylic rubber (ACM), silicone rubber (VMQ), fluorine rubber (FKM), and ethylene propylene rubber (EPDM). A material such as styrene butadiene rubber (SBR) can be used. When using a synthetic resin for the material of the ring member 21, for example, polyamide or the like can be used.

An example of calculating the allowance for the lip 23 is shown below. When the bearing is stopped or when rotating at a low speed, the lip portion 23 has a tightening allowance, but when the bearing rotates at a high speed, the allowance for the lip portion is set so that a harmful foreign substance does not enter the bearing. To do.

The table shown in FIG. 10 is an example of calculating the lip portion tightening allowance when the temperature difference between the inner race 2 of the bearing and the lip portion 23 is 10 ° C. When the bearing is stopped (25 ° C), it has a tightening margin of 0.3, but when the bearing rotates at a high speed (for example, a bearing temperature of 80 ° C and a lip temperature of 70 ° C), the tightening margin is -0.53 mm (0 .53 mm clearance). This clearance (0.53 mm) is a size that does not allow foreign matter to enter the bearing life significantly.

The calculation conditions here are set as follows.
Linear expansion coefficient: Seal lip (NBR): 2 × 10 ⁻⁴ , Inner ring (SUJ2): 12.5 × 10 ⁻⁶
Dimensions of both members: Seal lip inner diameter: φ99.7, inner ring outer diameter: φ100 → initial tightening allowance: φ0.3 mm

Further, it is desirable that the filtration hole 22a of the filter 22 has a maximum inner diameter of one filtration hole 22a of 0.3 mm to 0.7 mm. The maximum inner diameter of the filter hole 22a means the maximum length of the inner diameter in each direction around the filter hole 22a as shown in the example of the dimensions d1 and d2 in FIG. 9C. In particular, it is desirable that the filtration hole 22a has a circular cross section and the maximum inner diameter is 0.5 mm. However, in an actual product, it can be specified within a range of 0.3 to 0.7 mm by giving a manufacturing tolerance.

That is, if the filter hole 22a of the filter 22 is too large, large foreign matter will enter the bearing, and large indentations that will affect the life of the bearing will be formed on the raceway surface and rolling surface of the bearing. On the other hand, if the filter hole 22a is too small, the mesh may be clogged with foreign matter, and lubricating oil may not be supplied to the bearing.

Therefore, by conducting a life test, the size of the indentation generated on the raceway surface and rolling surface of the bearing and the rate of decrease in the life of the bearing due to the indentation are investigated. Confirmed not to give. In addition, an experiment confirmed the relationship between the size of the filtration hole 22a of the filter 22 and the size of the indentation formed by the foreign matter that passed through the filtration hole 22a.

11 (a) and 11 (b) show the experimental results. FIG. 11A shows the relationship between the size of the indentation generated on the raceway surface or rolling surface of the bearing and the rate of decrease in the life of the bearing accompanying the indentation (life ratio), and FIG. The relationship between the size and the size of the impression formed by the foreign matter that has passed through the mesh is shown.

The test conditions were a roller bearing with a tapered roller bearing with main dimensions (inner diameter, outer diameter, width) of φ30 mm × φ62 mm × 17.25 mm, radial load 17.65 kN, axial load 1.47 kN, shaft rotation speed 2000 min. ^-1 is set.

In the experiment, it was confirmed that when the size of the indentation formed on the raceway surface and the rolling surface of the bearing exceeds 1 mm, the life of the bearing rapidly decreases. In addition, it was confirmed that the mesh size capable of preventing the intrusion of foreign matters that would cause indentations exceeding 1 mm in size was 0.5 mm or less. For this reason, if the mesh size is 0.5 mm or less, the life of the bearing is particularly good. By setting the filter size to 0.7 mm or less, the impression that can be generated is 1.3 mm or less. If the indentation is 1.3 mm or less, it is possible to suppress the decrease in the life of the rolling bearing to a certain level (life ratio of 0.6 with respect to the one without the indentation).
Therefore, if the maximum inner diameter of the hole 22a is set to 0.7 mm or less, the life ratio of the bearing can be ensured to be 0.6, and a significant decrease in the bearing life can be prevented. In order to prevent clogging, the mesh size is desirably 0.3 mm or more.

In each of these embodiments, the ring member 21 including the filter 22 is attached to the outer race 1 that is a stationary race. Further, when the auxiliary ring member 24 is used, the auxiliary ring member 24 is attached to the inner raceway ring 2 that is the raceway on the rotation side. In other words, by attaching the ring member 21 including the filter 22 through which the lubricating oil is passed to the bearing ring on the stationary side of the bearing, it is possible to prevent a decrease in the oil permeability of the lubricating oil accompanying the rotation of the bearing. The filter is preferably stationary.

Accordingly, for example, conversely, when the inner race 2 is stationary and the outer race 1 is rotation, the ring member 21 is preferably attached to the inner race 2. At this time, when the auxiliary ring member 24 is used in combination, the auxiliary ring member 24 is attached to the outer race 1.

When the ring member 21 is attached to the inner race 2, the ring member 21 is formed on the outer side of the cylindrical engagement portion 21a along the outer diameter surface of the inner race 2 and the outer edge in the axial direction of the engagement portion 21a. The wall portion 21b rises toward the bearing ring 1 side. When the auxiliary ring member 24 is used, the auxiliary ring member 24 includes a cylindrical locking portion 24a along the inner diameter surface of the outer race ring 1, and the inner race ring 2 side from the outer edge in the axial direction of the lock portion 24a. It becomes a cross-sectional L-shaped member provided with the wall part 24b which stands | starts up over a perimeter. Since the other configuration is a configuration in which the inside and outside of the above embodiment are reversed, description thereof is omitted.

In these embodiments, a tapered roller bearing is adopted as the rolling bearing A, but the rolling bearing A is not limited to this. For example, a deep groove ball bearing or an angular ball bearing in which a ball as a rolling element 3 is incorporated between an outer ring as the outer race 1 and an inner ring as the inner race 2 and the ball is held by a cage. Good. Or the cylindrical roller bearing which incorporated the cylindrical roller as the rolling element 3 between the outer ring | wheel as the outer raceway ring 1 and the inner ring | wheel as the inner raceway ring 2, and hold | maintained the cylindrical roller with the holder | retainer may be sufficient.

In any type of bearing, the sealing device 20 is attached so as to cover the opening on one axial side in the bearing space of the rolling bearing A. However, if necessary, the same applies to the opening on the other axial side. A sealing device 20 may be attached. At this time, it is necessary to secure a space for the seal mounting portion in the bearing opening so that the seal device 20 does not interfere with the cage 6 and the rolling element 3.

A fourth embodiment of the invention according to the present application will be described with reference to FIGS.

In the fourth embodiment, one bearing ring of the rolling bearing A is an outer bearing ring (outer ring) 1 having a raceway surface 4 formed on the inner periphery. The other bearing ring is an inner bearing ring (inner ring) 2 having a raceway surface 5 formed on the outer periphery. The illustrated example shows single-row tapered roller bearings as race rings 1 and 2 and rolling elements 3, but the invention according to the present application is not limited to this, and ball bearings, cylindrical roller bearings, and double-row bearings. The present invention can also be applied.

The outer race 1 is a stationary ring supported by a housing (not shown). The inner race 2 is attached to a rotating shaft (not shown) and is a rotary wheel that rotates with respect to the outer race 1. A predetermined number of rolling elements 3 of 3 or more revolve while rotating between the raceway surfaces 4 and 5. Of the space formed between the two

race rings

1 and 2 in a state where the both race rings 1 and 2 are arranged concentrically, the space obtained through the rolling elements 3 is inside the bearing. Lubricating oil is supplied inside the bearing to lubricate the contact surface between the rolling element 3 and the

races

1 and 2. The space outside the space sandwiched between the race rings 1 and 2 in the radial direction is the outside of the bearing. Here, the axial direction refers to the direction along the central axis of the two

race rings

1 and 2 arranged concentrically, and the radial direction refers to the direction perpendicular to the central axis.

In the fourth embodiment, a ring member (seal ring) 36 attached to the outer race 1 is further provided. The ring member 36 is a contact seal that divides the inside of the bearing, which is a space formed between the race rings 1 and 2, with respect to the outside of the bearing, and suppresses intrusion of foreign matter from the outside at the relative rotation portion of the race rings 1 and 2. It has become. The outer race 1 has a fitting surface 7 formed in a cylindrical surface. The ring member 36 has an outer peripheral portion 38 that is press-fitted into the fitting surface 7. The ring member 36 is attached to the outer race 1 by this press fitting. The ring member 36 uses a metal ring having an outer peripheral portion 38 as a core material. The ring member 36 has an elastomeric lip 39 joined to the inner periphery of the core member.

The rolling bearing A further includes an auxiliary ring member (annular member) 40 that is attached to the inner race 2 and forms a labyrinth seal with the seal ring 36. The auxiliary ring member 40 is attached by press-fitting into the fitting surface 8 formed on the inner race ring 2. The auxiliary ring member 40 is formed with a seal surface that is in sliding contact with the lip portion 39 of the ring member 36. The lip 39 may be brought into sliding contact with the inner race 2 directly. The auxiliary ring member 40 has a side plate portion 32 that rises from the sealing surface. The side plate portion 32 is positioned on the bearing outer side with respect to the lip portion 39, and forms a labyrinth seal with the ring member 36. The labyrinth seal is a flow path that reduces the entry of foreign matter into the bearing from between the ring member 36 and the side plate portion 32 and between the side plate portion 32 and the side surface portion 37 of the lip portion 39 by the labyrinth effect.

The rolling bearing A further includes a filter 33 that filters the lubricating oil supplied from the outside of the bearing to the inside of the bearing. The filter 33 is formed by a plurality of filtration holes 34 that are passed through the ring member 36. As shown in FIGS. 13 and 14, each filtering hole 34 penetrates the radial intermediate portion of the ring member 36 that is out of the outer peripheral portion 38 and the lip portion 39 in the axial direction. Of the surface on the bearing outer side formed in the ring member 36, the hole peripheral portion 35 surrounding the filtration hole 34 projects in a tapered shape toward the outside of the bearing. The hole surrounding portion 35 is formed for each filtration hole 34 and includes a tip edge that defines an inlet of the filtration hole 34.

The filter 33 is formed only in the half-circumferential region of the ring member 36, as shown in FIG. Here, the half circumference means a half circumference around the axis C of the

races

1 and 2. In the half-circumferential region, a hole array portion in which two or more filtration holes 34 are arranged on a straight line in the radial direction is present at regular intervals in the circumferential direction around the axis C. The filter holes 34 are not limited to the radial mesh structure as shown in the figure. For example, the filter holes 34 can be arranged in a mesh shape in which a predetermined number is arranged in the chord direction and a predetermined number is also arranged in a direction perpendicular to the chord direction. is there. The arrangement of the filter holes 34 is not limited to the half circumference area of the ring member 36, and the entire circumference area is taken into consideration in consideration of the size and amount of foreign matter in the lubricating oil, the amount of lubricating oil supplied into the bearing, and the like. Etc. can also be arranged.

The rolling bearing A of the fourth embodiment is a radial bearing that supports the horizontal shaft, and an oil bath (not shown) is disposed outside the bearing, and the lubricating oil stored in the oil bath contains at least the ring member 36. It is assumed that it will be used in a state where the lower half circumference area sinks. In the figure, the oil level OL of the stored lubricating oil is drawn. A one-dot chain line in the left-right direction in the drawing passing through the axis C indicates a boundary position between the lower half circumference area and the upper half circumference area of the ring member 36. A large amount of foreign matter stays in the vicinity of the lower half circumference of the ring member 36 far from the oil level OL, and does not stay much in the vicinity of the upper half circumference of the ring member 36 near the oil level OL. In the fourth embodiment, a bearing is installed with the half circumference area of the ring member 36 without the filter 33 as a lower half circumference area, and lubricating oil with relatively little foreign matter is supplied into the bearing via a filter located above the seal ring. By doing so, clogging of the filter 33 can be prevented without making the filter 33 rough (that is, without increasing the minimum hole diameter at the inlet of each filtration hole 34).

Even if foreign matter is mixed in the lubricating oil in the vicinity of the oil level OL, as shown in FIGS. 12 to 14, foreign matter having a size that cannot pass through the inlet of the filtration hole 34 defined by the hole peripheral portion 35 is filtered. Without entering the hole 34, it is caught by the tip 33 of the hole peripheral portion 35 protruding toward the outside of the bearing, is captured by the filter 33, and then flows to the outside of the bearing. In addition, when a foreign matter that has moved to the side from the inlet of the filtration hole 34 is flowed toward the adjacent filtration hole 34, or a foreign matter directed toward the surface portion other than the hole peripheral portion 35 is directed to any one of the filtration holes 34. Even if it is flowed, the foreign matter is obstructed by the hole peripheral portion 35 protruding toward the outside of the bearing and cannot go to the inlet of the filtration hole 34, so that it will escape to the side of the hole peripheral portion 35. Or to the outside of the bearing. Therefore, the foreign matter can be prevented from becoming clogged with the filter hole 34. As described above, the fourth embodiment makes it difficult for foreign matter to stay in the state of blocking the inlet of the filtration hole 34 due to the three-dimensionalization of the hole surrounding portion 35, and thus prevents clogging without roughening the filter 33. it can.

Further, since the hole peripheral portion 35 is a tapered projecting surface tapered toward the outside of the bearing, the foreign matter caught on the tip edge of the hole peripheral portion 35 is easily inclined by the taper shape, and the hole It becomes easy to come off to the side from the inlet of the filtration hole 34 along the peripheral portion 35. For this reason, especially 4th embodiment can make it difficult to retain in the state which a foreign material block | closes the inlet_port | entrance of the filtration hole 34. FIG.

Although the hole surrounding portion 35 in the figure shows a conical shape that defines the inlet of the filtration hole 34 with the tip edge, the invention according to the present application is not limited to this, and a triangular pyramid shape, a quadrangular pyramid shape, and the like. An appropriate three-dimensional shape can be obtained. Note that the conical axis does not need to be oriented in the axial direction, but in order to obtain the same retention prevention performance regardless of where the foreign matter is caught around the hole, it should be set as close to the axial direction as possible. Is preferred.

In order to effectively prevent foreign matter from staying at the inlet of the filtration hole 34, the opening angle θ shown in FIG. 14 is preferably set within a range of 60 ° to 120 °. The opening angle θ is a tapered opening angle in the hole surrounding portion 35. More specifically, in the cut plane including the geometric center line of the hole surrounding portion 35 set in the axial direction, the angle formed by the upper bus bar of the hole surrounding portion 35 with respect to the center line, and the lower bus bar The total value of the angle formed with respect to the center line corresponds to the opening angle θ. If the opening angle θ is smaller than 60 °, the manufacturing is difficult and the shape becomes dangerous. For example, when the hole surrounding portion 35 is manufactured by press working on a metal plate, it is preferably 60 ° to 120 ° from the manufacturing surface of mold production or press processing itself. Further, in the case of a pressed product of a metal plate, there is a possibility that the plate edge may be injured during handling at an angle smaller than 60 °. Furthermore, at an angle smaller than 60 °, there is a possibility that the leading edge is deformed during handling or transport. On the other hand, when the opening angle θ is larger than 120 °, it is difficult for the foreign matter to easily come off the tip edge of the hole surrounding portion 15, and the possibility that the foreign matter stays in the filter portion increases.

The foreign matter passage prevention performance itself by the filtration hole 34 is determined by the diameter of the portion having the smallest inner diameter, that is, the inner diameter of the smallest hole diameter portion, when the single filtration hole 34 is focused. As shown in FIG. 13 and FIG. 14, the hole shape of the filtration hole 34 is set to be a round hole, and the inner diameter d3 of the minimum hole diameter part of the filtration hole 34 is that of the inlet defined by the tip edge of the hole peripheral part 35. It is set as the hole diameter. If the inner diameter d3 of the minimum hole diameter portion of the filter hole 14 is too large, large foreign matter reaches the inside of the bearing through the filter hole 34, so that large indentations that affect the life of the bearing are formed on the raceway surfaces 4 and 5. . On the other hand, if the inner diameter d3 of the minimum hole diameter portion of the filter hole 34 is too small, the filter hole 14 may be clogged with foreign matters, and the lubricating oil may not be supplied into the bearing.

Therefore, the present inventor conducted a life test under the following conditions (1) to (5) to find out the relationship between the size of the indentation, the diameter of the minimum hole diameter of the filtration hole, and the bearing life. The contents are as shown in FIGS. 11 (a) and 11 (b).

11A and 11B, the bearing life decreases rapidly when the size of the indentation exceeds 1 mm, and the life ratio is about 1.2 mm to 1.3 mm. I found that it was below. On the other hand, from FIGS. 11 (a) and 11 (b), it was also found that the inner diameter of the minimum hole diameter portion of the filtration hole where the size of the indentation is 1.3 mm is about 0.7 mm. Therefore, the size of the inner diameter of the minimum hole diameter portion in each filtration hole 34 is set to 0.7 mm or less, and the filter 33 as a whole has a numerical value of the largest one among the inner diameters of the minimum hole diameter portions in all the filtration holes 34 (the maximum inner diameter). Value) is set to 0.7 mm or less of the inner diameter limit value of the minimum hole diameter portion, it is considered that the bearing life ratio of 1.0 can be secured and the bearing life can be prevented from being lowered.

In an actual product, a dimensional error in manufacturing must be allowed when forming the filtration hole 34 as shown in FIGS. This dimensional error has no manufacturing difficulty if it is expected to be ± 0.2 mm. When the minimum hole diameter d3 is aimed at 0.5 mm, the minimum hole diameter d3 of each filter hole 34 of the filter 33 is within the range of 0.3 mm to 0.7 mm without any manufacturing difficulty. Thereby, the minimum hole diameter d3 can be increased as much as possible while preventing foreign matters exceeding 0.7 mm from passing through the filtration hole 34. Accordingly, the inner diameter d3 of the minimum hole diameter portion of the filtration hole 34 is preferably a value within the range of 0.3 to 0.7 mm.

On the other hand, at the outlet of the filter hole 34 through which the lubricating oil flows out into the bearing, it is preferable that the flow passage cross-sectional area be larger than the inlet. With this relationship, the resistance flowing out from the filtration hole 34 is reduced, and therefore, the possibility that foreign matter stays in the filtration hole 34 even if the foreign matter enters the bearing through the filtration hole 34 is reduced. For example, as shown in FIG. 14, the filtering hole 34 has an outlet hole diameter d4> an inlet hole diameter (inner diameter d3 of the minimum hole diameter portion), and a hole diameter closer to the outlet is larger than a hole diameter closer to the inlet. The hole shape can be made.

In particular, it is preferable that the inside of the filter hole 34 has a taper shape that widens from the bearing outer side toward the inner side. That is, if the filter hole 34 whose diameter gradually increases from the inlet hole diameter d3 to the outlet hole diameter d4 is adopted, foreign substances that have passed through the inlet are less likely to be clogged in the filter hole 34.

The amount of protrusion in the axial direction of the hole peripheral portion 35 is a value exceeding 0.7 mm in order to completely deviate 0.7 mm of foreign matter that adversely affects the bearing life as described above from the inlet of the filter hole 34. It is preferable to make it.

A fifth embodiment of the invention according to the present application will be described with reference to FIG. The fifth embodiment employs the invention of the outer peripheral portion 50 that causes a flow that hinders the approach to the inlet of the filter hole 34 (that is, the filter eyes) with respect to the lubricating oil in the fourth embodiment. Is. Hereinafter, only differences from the fourth embodiment will be described, and the same names and reference numerals are used for corresponding components. FIG. 16 illustrates oil bath lubrication in a state where the entire rolling bearing with seal is immersed in the lubricating oil. For this reason, the filtration hole 34 existing in the upper half circumference region of the ring member 36 is also immersed in the lubricating oil stored outside the bearing.

The auxiliary ring member 40 of the fifth embodiment has an outer peripheral portion 50 protruding from the side plate portion 32 toward the outside of the bearing. The outer peripheral portion 50 extends over the entire circumference of the auxiliary ring member 40 at a position aligned with the filtration hole 34 in the radial direction, and protrudes toward a virtual region extending from the inlet of the filtration hole 34 in the axial direction. Therefore, the overall three-dimensional shape of the outer peripheral portion 50 is a conical shape that tapers toward the inside of the bearing. As conceptually showing the flow of the lubricating oil in FIG. 16 with arrows, the lubricating oil is moved into the inner race as the inner race 2 (inner race) rotates with respect to the outer race 1 (outer race). The side plate portion 32 of the auxiliary ring member 40 that rotates integrally with the wheel 2 and the outer surface of the outer peripheral portion 50 are in contact with the outer surface of the bearing and receive a feeding action by centrifugal force. As a result, the lubricating oil is urged toward the filtering hole 34, and in particular, the lubricating oil in contact with the side plate portion 32 strikes the outer peripheral portion 50 outside the bearing and changes its direction, away from the ring member 36, and the filtering hole 34. This is a flow that obstructs the lubricating oil (arrow line in the left-right direction in the figure) that goes straight to the inlet extension of the filter hole 34 and goes straight to the inlet of the filter hole 34. As described above, the outer peripheral portion 50 causes a flow that obstructs the approach of the lubricating oil to the inlet of the filter hole 34 (that is, the filter eye), and therefore, foreign matter mixed in the lubricating oil is not easily pushed into the inlet of the filter hole 34. Become. Therefore, the fifth embodiment can prevent clogging without roughening the filter. Further, the fifth embodiment using the outer peripheral portion 50 in combination can prevent clogging more than the fourth embodiment.

A sixth embodiment of the invention according to the present application will be described with reference to FIGS. In the sixth embodiment, a number of wing parts 51 that cause the vortex of the lubricating oil by stirring the lubricating oil are further employed in the fourth embodiment. Hereinafter, only differences from the fourth embodiment will be described, and the same names and reference numerals are used for corresponding components. FIGS. 17 and 18 also illustrate oil bath lubrication in a state where the entire rolling bearing with seal is immersed in the lubricating oil.

The auxiliary ring member 40 of the sixth embodiment has a wing part 51 protruding in the radial direction from the side plate part 32. Two or more wing parts 51 are arranged at equal intervals in the circumferential direction. Along with the rotation of the inner raceway ring 2, a large number of wing parts 51 of the auxiliary ring member 40 that rotates integrally with the inner raceway ring 2 agitate the lubricating oil in the rotation direction near the filter 33 outside the bearing, and the filter 33. Occurrence of the vortex of the lubricating oil in contact with the vortex (the state of the vortex indicated by the arrow in FIG. 18 is generated). This vortex has the effect of flowing foreign matter from the eyes of the filter 33. For this reason, the sixth embodiment can prevent clogging without making the filter 33 rough. Further, the sixth embodiment using the wing portion 51 in combination can prevent clogging more than the fourth embodiment.

In addition, the wing | blade part 51 is made into the shape along the radial direction in the whole of the both wing surfaces which faced the axial direction. Since both of these blade surfaces are flush with both side surfaces of the side plate portion 32, it can be formed by a simple process of cutting out the annular plate-shaped material portion radially from the outer peripheral side. When the vortex of the lubricating oil is desired to be generated more strongly, the stirrability may be enhanced by bending the plate edge on the front side in the rotational direction of the wing portion 51 in the axial direction.

A seventh embodiment of the invention according to the present application will be described with reference to FIG. The seventh embodiment is obtained by changing only the shape of the hole peripheral portion in the fourth embodiment. That is, the filter 43 of the seventh embodiment has a hole surrounding portion 42 surrounding the filtration hole 41 protruding in a cylindrical shape. Thus, the foreign matter having a size that cannot pass through the inlet of the filter hole 41 is caught by the hole peripheral part 42 and does not enter the filter hole 41 by the non-tapered hole peripheral part 42. Then, it is flowed to the outside of the bearing. Further, even if foreign matter directed to the surface portion other than the hole peripheral portion 42 of the ring member 36 flows toward the filtration hole 41 along the surface portion, the hole peripheral portion 42 protruding toward the outside of the bearing. It is not possible to go to the inlet of the filter hole 41 due to the obstacle. Thus, according to the seventh embodiment, clogging can be prevented without roughening the filter.

The technical scope of the present invention is not limited to the above-described embodiments, but includes all modifications within the scope of the technical idea based on the description of the scope of claims. Only one feature of each of the above-described inventions may be employed, or two or more features may be employed in combination as appropriate.

1 Outer ring (outer raceway)
2 Inner ring (inner race)
2b Large collar part 2c Small collar part 3 Tapered rollers (rolling elements)
4, 5 Raceway surface 6

Cage

20, 30

Sealing device

21, 36 Ring member (seal ring)

21a Locking part

21b Wall part 21c Tip

21d Guide part

21e Escape part

22, 33, 43

Filter 22a Hole

23, 39

Lip part

24, 40 Auxiliary ring member (annular member)

24a Locking part

24b Wall part 32

Side plate part

34, 41

Filtration hole

35, 42 Peripheral part 37 Side face part 50 Outer part 51 Wing part A Rolling bearing

Claims

A rolling element (3) is incorporated between the outer race ring (1) and the inner race ring (2), and a bearing space formed between the outer race ring (1) and the inner race ring (2). In a rolling bearing with a filter, wherein at least one opening is covered with a sealing device (20, 30), and a foreign substance contained in the lubricating oil is captured by a filter (22) included in the sealing device (20, 30).
The sealing device (20) includes a ring member (21, 36) integrally formed with a filter (22, 33, 43) through which lubricating oil can pass and restricts the passage of solid foreign matter, and the outer race (1). ) Or one of the inner race rings (2), the lip portions (23, 39) which are joined to the ring members (21, 36) and made of a softer material than the ring members, Rolling bearing with filter facing the ring.
An auxiliary ring member (24, 40) is mounted on the other race ring, and the auxiliary ring member (24, 40) is made to face the lip portion (23, 39) of the ring member (21, 36), so that the auxiliary The rolling bearing with a filter according to claim 1, wherein a labyrinth structure is formed between the ring member (24, 40) and the ring member (21, 36).
When the relative rotation around the axis of the outer raceway (1) and the inner raceway (2) is stopped or during low-speed rotation, the lip portion (23, 39) is attached to the other raceway or the other raceway. The lip portion (23, 39) is set so as not to contact the other track ring or a member fixed to the other track ring during high-speed rotation while contacting a fixed member. A rolling bearing with a filter according to 1 or 2.
The ring member (21, 36) is mounted on a stationary ring of the inner race (2) or the outer race (1). Rolling bearing with filter as described in 1.
The inner race (2) is on the rotating side, the outer race (1) is stationary, and the ring members (21, 36) are mounted on the outer race (1). The rolling bearing with a filter according to claim 4.
The filter (22, 33, 43) is formed on the entire surface of the ring member (21, 36) or a portion excluding a fitting surface to the one raceway ring. The rolling bearing with a filter according to any one of 5.
The ring members (21, 36) are formed by metal rings constituting a filter (22, 33, 43) or injection molding by a large number of filter holes (22a, 34, 41) formed by pressing. The rolling bearing with a filter according to claim 6, wherein the filter bearing is a synthetic resin ring constituting a filter (22, 33, 43) by a large number of filtering holes (22a, 34, 41).
The filter (22, 33, 43) is formed by a plurality of filtering holes (22a, 34, 41) passed through the ring member (21, 36), and formed in the ring member (21, 36). The hole surrounding part (35, 42) surrounding the said filtration hole (22a, 34, 41) among the surfaces of the outer side of the bearing which were made protrudes toward the bearing outer side. To 7 with a seal.
The rolling bearing with seal according to claim 8, wherein the hole peripheral portion (35, 42) projects in a tapered shape toward the outside of the bearing.
The rolling with a seal according to any one of claims 1 to 9, wherein an inner diameter of a minimum hole diameter portion of the filtration hole (22a, 34, 41) is a value within a range of 0.3 to 0.7 mm. bearing.
The rolling bearing with seal according to any one of claims 1 to 10, wherein the inside of the filtration hole (22a, 34, 41) has a tapered shape that becomes wider from the bearing outer side toward the inner side.
The auxiliary ring member (24, 40) has an outer peripheral portion protruding toward the outside of the bearing so as to cause a flow that obstructs the approach of the lubricating oil to the filter (22, 33, 43) with the rotation ( 50) The rolling bearing with seal according to claim 2, characterized in that it has 50).
The auxiliary ring member (24, 40) has a blade portion (51) that causes a vortex of the lubricating oil in contact with the filter (22, 33, 43) on the outer side of the bearing as the other race ring rotates. The rolling bearing with seal according to claim 2, wherein the rolling bearing has a seal.
The rolling with a seal according to any one of claims 1 to 13, wherein the filter (22, 33, 43) is formed only in a half-circumferential region of the ring member (21, 36). bearing.