JP2009162341A - Rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing capable of preventing the deterioration of the rigidity of a main shaft, achieving the compactness of a machine, and providing a high-speed long service life and maintenance-free performance. <P>SOLUTION: A grease sump 4 is disposed to adjoin one axial direction end face of a bearing on the side with an inner ring inclination part CB, and a nozzle 7 projecting from the grease sump 4 is provided to cover the outer circumference of the inner ring inclination part CB. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a rolling bearing used for a machine tool spindle or the like used for grease lubrication.

As a lubrication method for machine tool spindle bearings, grease lubrication that can be used maintenance-free, air-oil lubrication that mixes lubricating oil with carrier air and injects oil into the bearing from the nozzle, and directly injects bearing oil into the bearing. There are methods such as jet lubrication.
In recent machine tools, in order to increase machining efficiency, there is a tendency for higher speed, and lubrication of main shaft bearings is also relatively inexpensive and air-oil lubrication that can be speeded up easily is often used. However, this air oil lubrication method has a problem from the viewpoint of cost, noise, energy saving, and resource saving because it requires an air oil supply device as ancillary equipment and requires a large amount of air. There is also a problem of deteriorating the environment due to the scattering of oil. In order to avoid these problems, recently, speeding up by grease lubrication has begun to attract attention, and requests have been increasing.

  Since grease lubrication is performed only with the grease enclosed during bearing assembly, high-speed operation may lead to premature seizure due to deterioration of the grease due to bearing heat generation and oil film breakage on the raceway surface, especially the inner ring. . In particular, it is difficult to guarantee the grease life in a high-speed rotation region where the dn value exceeds 1 million (bearing inner diameter mm × rotational speed rpm).

New proposals have been introduced as a means of extending the life of grease. For example, there is a proposal (Patent Document 1) aiming at high speed and long life by providing a grease reservoir on the outer ring raceway surface portion. In addition, there is a proposal (Patent Document 2) in which a bearing is properly lubricated and lubricated by a grease replenishing device provided outside the spindle.
Japanese Patent Laid-Open No. 11-108068 JP 2003-113998 A JP 2006-132765 A

However, the technologies of the above proposed examples are not satisfactory when considering the number of rotations used (> dn value 1.5 million) equivalent to air-oil lubrication and maintenance-free.
The present applicant has proposed a technique (Patent Document 3) obtained by developing the technique of Patent Document 1. In this Patent Document 3, the base oil of grease is near the capillary phenomenon or the bearing raceway surface between the gap forming piece extending from the grease reservoir adjacent to the bearing front side and the step surface provided near the outer ring rolling surface. It is carried by air flow etc. and supplied to the rolling surface. Further, it is not necessary to convey the lubricating oil by air or the like. With this technology, only the grease sealed in the grease reservoir is used to achieve high speed, long life and maintenance-free bearings.

In this technique, a gap forming piece extending from a grease reservoir is inserted from the outer ring counter side to the outer ring inner diameter side. Therefore, in order to apply this technology to angular contact ball bearings with a contact angle, it is necessary to place a grease reservoir adjacent to the front side of the angular contact ball bearing, and the distance between the bearing and the spindle tip tool becomes undesirably longer. End up.
On the other hand, in machine tool spindles that often support the fixed side, that is, the tool side, with the back combination of angular ball bearings, the distance between the bearing and the spindle tip (tool) is shortened to prevent rigidity reduction and downsizing of the machine. It is common to do.

  An object of the present invention is to provide a rolling bearing capable of preventing a reduction in main shaft rigidity, reducing the size of a machine, and enabling high speed and long life and maintenance-free operation.

  A rolling bearing according to the present invention is a rolling bearing having an inner ring, an outer ring, and a plurality of rolling elements interposed between the raceways of the inner and outer rings, and a raceway of the inner ring from an end surface side of the inner ring to the outer diameter portion of the inner ring. An inner ring inclined portion having a larger diameter toward the surface side is provided, a grease reservoir disposed adjacent to one axial direction of the bearing end surface on the side having the inner ring inclined portion, and the inner ring inclined protruding from the grease reservoir And a nozzle including a base oil discharge part that oozes out the base oil of the grease.

  According to this configuration, the grease reservoir is disposed adjacent to one axial direction of the bearing end surface on the side where the inner ring inclined portion is located, and the nozzle protruding from the grease reservoir is provided so as to cover the outer periphery of the inner ring inclined portion. Without providing a stepped surface or the like in the vicinity of the rolling surface, the nozzle can be inserted into the bearing, and the base oil of grease can be oozed out from the base oil discharge portion of the nozzle. The grease base oil in the grease reservoir is separated by heat generation due to rotation of the inner ring of the bearing and an increase in grease pressure caused by temperature rise. For example, this base oil is supplied to the inner ring raceway surface or rolling elements by the air flow generated by the inner ring rotation, or the inner ring raceway surface via the slope of the inner ring inclined portion by the centrifugal force and surface tension of the inner ring rotation. To contribute to lubrication.

  Therefore, there is no need to forcibly convey the lubricating oil by air or the like, and the grease enclosed in the grease reservoir can be used to realize high speed, long life, and maintenance-free bearings. Since no step surface or the like is provided near the outer ring rolling surface, a reduction in bearing rigidity can be prevented and the bearing size can be reduced accordingly. Since the rigidity of the bearing can be ensured, it is possible to prevent the main shaft rigidity from being lowered. By eliminating the means for forcibly conveying the lubricating oil, the structure can be simplified and the entire machine and apparatus can be reduced in size.

In this invention, it is an angular ball bearing, The grease pool may be provided adjacent to the rear surface of the outer ring of the angular ball bearing. Thus, by providing the grease reservoir adjacent to the back surface of the outer ring, for example, when the main shaft or the like is supported by the back surface combination of the angular ball bearing, the distance between the bearing and the front end of the main shaft can be shortened.
In other words, when a grease reservoir is provided adjacent to the front surface of the outer ring as in the prior art to form a rear combination of the angular ball bearings, the grease reservoir is located at the tip side of the bearing, that is, near the tool side. Moreover, the grease reservoir is located at the rear end side, that is, the rear end of the rear bearing. Accordingly, the entire length of the grease reservoir is undesirably increased in the axial direction.
In the present invention, when the grease reservoir is provided adjacent to the rear surface of the outer ring, such problems can be solved, the main shaft rigidity can be prevented from being lowered, and the size of the machine can be reliably reduced.

  It is the said angular ball bearing provided in a vertical axis | shaft, Comprising: You may provide the said grease reservoir in the upper part of this angular ball bearing. In this case, the base oil separated from the grease reservoir can be naturally moved to the bearing side by the action of gravity and supplied to the raceway surface. Therefore, a means for forcibly conveying the base oil is not required, and the structure can be simplified. Accordingly, the manufacturing cost can be reduced.

A brush-like or cloth-like base oil permeating means that permeates the base oil may be provided in the vicinity of the base oil discharge portion of the nozzle. In this case, the base oil separated from the grease can permeate the base oil permeating means and reliably move onto the slope of the inner ring slope portion, thereby contributing to lubrication.
A groove for guiding the base oil discharged from the base oil discharge portion to the raceway surface of the inner ring may be formed in the inner ring inclined portion. By forming an optimal groove extending to the vicinity of the raceway surface of the inner ring on the slope of the inner ring slope, an air flow efficiently flows from the small diameter side to the large diameter side on the slope of the inner ring slope, and base oil discharge The base oil discharged from the section is reliably conveyed to the raceway surface or the rolling element, and can contribute to lubrication.

  The nozzle has a nozzle inner diameter side inclined surface substantially parallel to the inclined surface of the inner ring inclined portion, and a groove for guiding the base oil discharged from the base oil discharge portion to the vicinity of the rolling element is formed on the nozzle inner diameter side inclined surface. May be. In this case, the air flow efficiently flows from the small diameter side to the large diameter side of the bearing inner ring, and the base oil discharged from the base oil discharge part is reliably conveyed to the raceway surface or the rolling element, thereby contributing to lubrication. .

  A holder that holds the plurality of rolling elements, and the axial distance between the tip of the nozzle and the center of the rolling element is smaller than the axial distance between the center of the rolling element and the pocket inner diameter portion of the holder; You may prescribe. In this case, the airflow flowing from between the slope of the inner ring inclined portion and the nozzle inner diameter side slope becomes easy to flow toward the raceway surface, and the base oil can be reliably supplied to the rolling elements and the raceway surface.

A retainer for holding the plurality of rolling elements may be provided, and an inner diameter side pocket portion having a diameter larger than a reference diameter of the pocket portion of the retainer may be provided on an inner diameter surface of the retainer. In this case, the air flow carrying the base oil is prevented from moving away from the rolling element between the inclined surface of the inner ring inclined portion and the nozzle inner diameter-side inclined surface, and the base oil is captured by the inner diameter-side pocket portion and the rolling element or the track. The surface can be reliably supplied.
In this invention, it may be an angular ball bearing that supports the machine tool spindle. The base oil separated from the grease in the grease reservoir is used without extending the axial length from the bearing to the shaft end for installing the grease reservoir as in the prior art where a grease reservoir was installed on the front side of the bearing. Can be applied to the field of machine tool spindles.

A rolling bearing according to the present invention is a rolling bearing having an inner ring, an outer ring, and a plurality of rolling elements interposed between the raceways of the inner and outer rings, and a raceway of the inner ring from an end surface side of the inner ring to the outer diameter portion of the inner ring. There is an inner ring inclined part that becomes larger in diameter toward the surface side,
A grease reservoir disposed adjacent to one axial direction of the bearing end surface on the side where the inner ring inclined portion is present, and a nozzle that protrudes from the grease reservoir and covers the outer periphery of the inner ring inclined portion, and oozes the base oil of the grease Since it has the nozzle including the base oil discharge part to be taken out, it is possible to prevent a decrease in the rigidity of the main shaft, to reduce the size of the machine, and to enable high speed and long life and maintenance-free.

A first embodiment of the present invention will be described with reference to FIGS.
The rolling bearing according to the first embodiment has a plurality of rolling elements 3 interposed between the raceways 1a and 2a of the inner ring 1, the outer ring 2, and the inner and outer rings 1 and 2, and is provided on the bearing back surface, that is, the outer ring back surface 2h. A grease reservoir 4 which will be described later is disposed adjacently. The plurality of rolling elements 3 are outer ring guide type cages 5 and are held by a cage 5 having a cylindrical shape and a plurality of pockets 5a formed at predetermined intervals. This rolling bearing is an angular ball bearing, and the inner ring 1 of this angular ball bearing is, for example, fitted into a machine tool main shaft (not shown) to be rotatable, and the outer ring 2 is fitted to the inner periphery of a housing (not shown) in the spindle unit. Fixed and supported in the combined state.

  In the outer diameter portion of the inner ring 1 is provided an inner ring inclined portion CB so-called inner ring counter portion that increases in diameter from the end surface side of the inner ring 1 toward the raceway surface 1a. That is, the inner ring counter portion is provided in the outer diameter portion of the inner ring 1 that continues to the edge portion on the opposite side to the direction in which the contact angle α1 occurs on the raceway surface 1a. An inner ring spacer 6 is provided that is inward of the grease reservoir 4 in the radial direction and abuts adjacent to the inner ring front surface 1s. The inner ring front surface 1s continues to the smallest diameter portion of the inner ring counter portion.

The grease reservoir 4 and the nozzle 7 will be described.
The grease reservoir 4 has an annular container portion 8 in which grease is accumulated. A nozzle 7 is provided so as to protrude from the container part 8 in the axial direction, that is, into the bearing, and covers the outer periphery of the inner ring inclined part CB. The nozzle 7 includes a base oil discharge portion 7a that exudes the base oil of the grease Gr.
The annular container portion 8 includes an outer cylindrical portion 9 as an outer ring positioning spacer, an inner cylindrical portion 10 disposed on an outer diameter surface 6a of the inner ring spacer 6 via a predetermined radial gap δ1, and these inner and outer cylinders. One side surface portion 11 that covers most of one side surface of the portions 10 and 9 and another side surface portion 12 that closes the other side surface of the inner and outer cylinder portions 10 and 9 are provided. Grease Gr is enclosed in an annular space surrounded by the outer cylinder part 9, the inner cylinder part 10, the one side part 11, and the other side part 12. A grease sealing hole (not shown) for sealing the grease Gr in the container portion 8 is formed at one place, for example, in the circumferential direction of the other side surface portion 12.

  The nozzle 7 protrudes from the radially inner peripheral edge of the one side surface portion 11 to the axial direction one side in the axial direction, and from the right end of the inner cylinder portion 10 to the axial direction. And an inner peripheral side nozzle body 14. An annular grease base oil permeation gap δ <b> 2 is formed between the outer diameter surface 14 a of the inner peripheral side nozzle body 14 and the inner diameter surface 13 a of the outer periphery side nozzle body 13. In addition, one inclined surface 13b that covers the inner ring inclined portion CB of the outer peripheral side nozzle body 13 and another inclined surface 14b that covers the inner ring inclined surface CB of the inner peripheral side nozzle body 14 are outer diameter surfaces of the inner ring inclined surface CB. Are spaced apart by a certain annular gap δ3. The nozzle inner diameter side inclined surface 15 is formed by the one inclined surface 13b and the other inclined surface 14b.

The base oil discharge portion 7a of the nozzle 7 is a slit formed over the entire circumference between one axial end of the one slope 13b and the other axial end of the other slope 14b, and is inserted into the grease base oil permeation gap δ2. Communicate. The base oil discharge portion 7a is opened in a direction substantially orthogonal to the nozzle inner diameter side inclined surface 15 and communicates with the grease base oil permeation gap δ2. The slit may not be formed over the entire circumference. For example, the slits may be arranged at regular intervals in the circumferential direction, in other words, the slits may be formed equally spaced around the circumference so that the grease base oil is uniformly discharged on the circumference.
The base oil discharge part 7a, the grease base oil permeation gap δ2 and the inside of the container part 8 communicate with each other, so that the base oil of the grease Gr sealed in the container part 8 becomes the grease base oil permeation gap δ2. Is guided to the base oil discharge part 7a and is used for bearing lubrication as will be described later.

  The grease reservoir 4 and the nozzle 7 may be sealed with, for example, a detachable sealing member (not shown), for example, in the state of separate parts before being assembled to the rolling bearing. In this case, even if the grease reservoir 4 and the nozzle 7 are handled as separate products, the grease Gr is not exposed, and can be easily handled without giving any concern about the management of the amount of grease charged, thereby improving the reliability of the product. be able to. When the grease reservoir 4 and the nozzle 7 are integrated into a rolling bearing, the sealing member is removed to ensure a flow path for the base oil discharge part 7a.

The operation of the rolling bearing in which the grease reservoir 4 and the like are assembled as shown in FIG. 1 will be described.
When the bearing is incorporated in the main shaft or the like, the grease 8 is filled in the container 8 of the grease reservoir 4, the grease base oil permeation gap δ2, and the base oil discharge part 7a. Gr is enclosed.

  When the bearing is operated, the base oil and the thickener having different expansion coefficients are separated due to the temperature rise during operation in the grease Gr stored in the sealed container portion 8 or the like. At the same time, the internal pressure of the sealed container part 8 increases. Due to this internal pressure, the separated base oil remains in the vicinity of the base oil discharge portion 7a via the grease base oil permeation gap δ2.

Here, the case where grease base oil is conveyed from the base oil discharge part 7a by the centrifugal force of inner ring | wheel rotation is demonstrated.
Since the base oil is continuously discharged from the grease reservoir 4 due to the temperature rise, the base oil eventually rises due to the surface tension and comes into contact with the inner ring inclined portion CB.
The base oil in contact with the inner ring inclined portion CB moves on the inclined surface from the portion attached by the surface tension and the centrifugal force toward the tapered large diameter side of the inner ring inclined portion CB, and eventually reaches the raceway surface 1a to be lubricated. Contribute to. The inclination angle α2 with respect to the axial direction of the inner ring inclined portion CB can be optimally set so that the base oil can be easily moved by surface tension and centrifugal force in consideration of the base oil viscosity, the inner ring rotation speed, and the like.
As shown in the following table, in the test, the relationship between the inclination angle α2 and the rotational speed of the bearing to which the oil can move was confirmed.

When the temperature rises to a steady state, the internal pressure increase factor disappears, so that the internal pressure gradually decreases in parallel with the base oil discharge, and the base oil discharge amount per unit time also decreases. Thereafter, when the operation is stopped, the temperature of the grease reservoir 4 also decreases, and the internal pressure of the grease reservoir 4 becomes substantially atmospheric pressure. At this time, there is no discharge of the base oil due to pressure, and the base oil discharge portion 7a is filled with the base oil. Therefore, in the operation stop state, the grease reservoir 4 is in a sealed state.
Thereafter, when the operation is restarted, the internal pressure of the grease reservoir 4 rises again. By such a heat cycle of temperature rise and fall, pressure fluctuations in the grease reservoir 4 are repeated, and the base oil separated from the grease Gr is surely moved to the base oil discharge part 7a of the nozzle 7 so that the inner ring 1 It is repeatedly supplied to the raceway surface 1 a, the rolling elements 3, and the raceway surface 2 a of the outer ring 2.

In the present embodiment, the case where the grease base oil is carried from the base oil discharge part 7a by the centrifugal force of the inner ring rotation has been described. Instead, the case where the grease base oil is carried by the air flow in the bearing will be described.
When the bearing is operated, the base oil and the thickener having different expansion coefficients are separated due to the temperature rise during operation in the grease Gr stored in the sealed container portion 8 or the like. At the same time, the internal pressure of the sealed container part 8 increases. Due to this internal pressure, the separated base oil remains in the vicinity of the base oil discharge portion 7a via the grease base oil permeation gap δ2.

Although the base oil is continuously discharged from the grease reservoir 4, when the rotational speed is high and the air flow inside the bearing is strong, before the base oil contacts the inner ring inclined portion CB as described above, the vicinity of the base oil discharge portion 7a May be skipped from.
The blown base oil rides on the air flow and is supplied to the inner ring raceway surface 1a, the rolling elements 3 and the like, and contributes to lubrication. In the operation stop state, there is no discharge of base oil due to pressure, and the base oil discharge portion 7a is filled with base oil. Therefore, in the operation stop state, the grease reservoir 4 is in a sealed state.

  When the base oil is carried by the air flow in the bearing, the axis between the tip 7b of the nozzle 7 and the rolling element center P1 is larger than the axial distance L1 between the rolling element center P1 and the pocket inner diameter portion of the cage 5. The direction distance L2 may be defined to be small. According to this configuration, it is possible to prevent the air flow flowing from the base oil discharge part 7a from moving away from the retainer 5, and to supply the base oil more reliably from the inner diameter side of the retainer 5 to the rolling part.

  According to the rolling bearing according to the first embodiment described above, the grease reservoir 4 is disposed adjacent to one axial direction of the bearing end surface on the side where the inner ring inclined portion CB is located, and the nozzle protruding from the grease reservoir 4 7 is provided so as to cover the outer periphery of the inner ring inclined portion CB, so that the nozzle G is inserted into the bearing without providing a stepped surface near the outer ring raceway surface, and the grease Gr from the base oil discharge portion 7a of the nozzle 7 The base oil can be exuded. The base oil is separated by the increase in the pressure of the grease Gr caused by the heat generated by the rotation of the inner ring of the bearing and the temperature rise. This base oil is supplied to the inner ring raceway surface 1a via the slope of the inner ring inclined portion CB by the centrifugal force of the inner ring rotation, or to the inner ring raceway surface 1a, the rolling element 3 and the like by the air flow generated by the inner ring rotation. Supplied and contributes to lubrication.

  Therefore, it is not necessary to forcibly convey the lubricating oil by air or the like, and the grease Gr enclosed in the grease reservoir 4 can be used to realize a high-speed bearing, a long life, and maintenance-free. Since no step surface or the like is provided in the vicinity of the outer ring raceway surface, it is possible to reduce the bearing size by reducing the rigidity of the bearing. Since the rigidity of the bearing can be ensured, it is possible to prevent the main shaft rigidity from being lowered. Further, since the nozzle 7 is provided so as to cover the outer periphery of the inner ring inclined portion CB of the angular ball bearing, and it is not necessary to provide a step surface or the like in the vicinity of the outer ring raceway surface, the outer ring guide type cage 5 can be employed. Thus, the speed of the bearing can be further increased. By eliminating the means for forcibly conveying the lubricating oil, the structure can be simplified and the entire machine and apparatus can be reduced in size.

In the present embodiment, by providing the grease reservoir 4 adjacent to the outer ring rear surface 2h of the angular ball bearing, for example, when supporting the main shaft or the like by the rear combination of the angular ball bearing, the distance between the bearing and the front end of the main shaft is increased. Can be shortened.
In other words, when a grease reservoir is provided adjacent to the front surface of the outer ring as in the prior art to form a rear combination of the angular ball bearings, the grease reservoir is located at the tip side of the bearing, that is, near the tool side. Moreover, the grease reservoir is located at the rear end side, that is, the rear end of the rear bearing. Accordingly, the entire length of the grease reservoir is undesirably increased in the axial direction.
In the present embodiment, since the grease reservoir 4 is provided adjacent to the rear surface 2h of the outer ring, such a problem can be solved, the main shaft rigidity can be prevented from being lowered, and the machine can be reliably reduced in size.

  Moreover, since the base oil discharge part 7a of the nozzle 7 is a slit formed over the entire circumference, the discharged base oil oozes out without a break on the circumference. Therefore, the base oil can be more reliably supplied to the raceway surface 1a. In the case where the slits are formed in a uniform circumference and the grease base oil is uniformly discharged on the circumference, the outer peripheral side nozzle main body 13 and the inner peripheral side nozzle main body 14 are arranged between the slits ( (Not shown), the rigidity can be increased. Therefore, the grease base oil permeation gap δ2 and the slit width of the base oil discharge part 7a can be kept constant. As a result, the grease base oil can be stably supplied to the raceway surface 1a and the like without stagnation. Furthermore, since the annular gap δ3 between the nozzle inner diameter side inclined surface 15 and the inner ring inclined portion CB of the inner ring 1 can be kept constant, the lubrication reliability of the base oil passing through the annular gap δ3 is improved, and the bearing High speed and long life can be achieved. Since the said rigidity can be improved, especially the one side part 11 and the other side part 12 among the container parts 8 can be reduced in thickness, and it becomes possible to achieve the weight reduction of the whole by this.

Next, a modified embodiment in which the rolling bearing according to the first embodiment of the present invention is partially changed will be described with reference to FIGS.
In the following description, the same reference numerals are given to portions corresponding to the matters described in the preceding forms in each embodiment, and overlapping description may be omitted. When only a part of the configuration is described, the other parts of the configuration are the same as those described in the preceding section. Not only the combination of the parts specifically described in each embodiment, but also the embodiments can be partially combined as long as the combination does not hinder.

FIG. 3A is a cross-sectional view in which a groove is formed in the inner ring inclined portion of the rolling bearing, and FIG. 3B is a plan view showing a cutaway portion of the inner ring inclined portion. This will be described with reference to FIGS. When the grease base oil is carried by the air flow in the bearing, a plurality of grooves CB1 are formed in the inner ring inclined portion CB so that the air flow can easily flow from the base oil discharge portion 7a toward the raceway surface. These grooves CB1 are formed at regular intervals in the circumferential direction, and each groove CB1 is formed, for example, so as to extend from the inner diameter side to the vicinity of the inner ring raceway surface 1a along the axial direction. However, each groove CB1 may be formed short enough to extend from a portion facing the base oil discharge portion 7a in the inner ring inclined portion CB to the vicinity of the inner ring raceway surface 1a.
According to this configuration, the rolling element 3 side becomes lower pressure than the base oil discharge part 7a due to the inner ring rotation, and the air flow efficiently flows from the small diameter side to the large diameter side of the inner ring inclined part CB, and from the base oil discharge part 7a. The discharged base oil is reliably conveyed to the raceway surface 1a or the rolling element 3, and can contribute to lubrication.

  FIG. 4 is a plan view when the groove of the inner ring inclined portion is angled with respect to the axial direction, and FIG. 5 is a plan view when the groove of the inner ring inclined portion is curved. Even in this case, the rolling element 3 side becomes a lower pressure than the base oil discharge part 7a due to the inner ring rotation, and the air flow can flow more efficiently and smoothly from the small diameter side to the large diameter side of the inner ring inclined part CB. Thereby, the base oil discharged from the base oil discharge part 7a is reliably conveyed to the track surface 1a or the rolling element 3, and can contribute to lubrication. 4 and 5, each groove CB1 may be formed short enough to extend from the portion facing the base oil discharge portion 7a in the inner ring inclined portion CB to the vicinity of the inner ring raceway surface 1a.

FIG. 6 is a plan view when the groove of the inner ring inclined portion is formed in a spiral shape according to the modified embodiment.
In this case, the rolling element 3 side has a lower pressure than the base oil discharge part 7a due to the inner ring rotation, and the air flow can flow most efficiently and smoothly from the small diameter side to the large diameter side of the inner ring inclined part CB. The base oil discharged from the base oil discharge part 7a is reliably conveyed to the raceway surface 1a or the rolling element 3, and can contribute to lubrication.
3 to 6, the groove CB1 may be formed not to the vicinity of the inner ring raceway surface 1a but to the inner ring raceway surface 1a. In this case, even if the base oil that has not been blown off by the air flow adheres to the groove CB1, the base oil can be easily carried to the inner ring raceway surface 1a by centrifugal force due to the inner ring rotation.

FIG. 7A is a cross-sectional view of the main part when a groove is formed on the inner diameter side slope of the nozzle, and FIG. 7B is a bottom view of the inner diameter side slope of the nozzle viewed from the radially inner side. is there.
A plurality of grooves 13ba are formed at regular intervals in the circumferential direction on one inclined surface 13b covering the inner ring inclined portion CB of the outer peripheral side nozzle body 13. Each groove 13ba is formed along the axial direction from one axial end of the inclined surface 13b to the other axial end.

  According to this configuration, the rolling element 3 side has a lower pressure than the base oil discharge portion 7a due to the inner ring rotation, and the air flow is an annular gap δ3 between the inner diameter side inclined surface 15 of the nozzle 7 and the inner ring inclined portion CB (see FIG. 2). ) Efficiently flows from the small diameter side toward the large diameter side, and the base oil discharged from the base oil discharge portion 7a is reliably conveyed to the raceway surface 1a or the rolling element 3 and can contribute to lubrication. However, the groove 13ba may be angled with respect to the axial direction as provided in the inner ring inclined portion CB, or may be formed in a spiral shape. A groove 13ba formed on the inner diameter side inclined surface 15 of the nozzle 7 in FIG. 7 and the like and at least one groove CB1 in FIGS. 3 to 6 may be provided in combination.

Next, a second embodiment of the present invention will be described with reference to FIG.
In the rolling bearing according to the second embodiment, the base oil permeating means 16 that permeates the base oil is provided in the vicinity of the base oil discharge portion 7 a of the nozzle 7. The base oil permeating means 16 is realized by, for example, a brush-like member or a cloth-like member formed of a material that can withstand wear due to rotation of the inner ring. However, the base oil permeating means 16 is not limited to the brush-like member or the cloth-like member as long as it has a function of permeating the base oil and does not adversely affect the rotation of the inner ring. The base oil permeating means 16 is formed along a slit that forms the base oil discharge portion 7a.
According to this configuration, the base oil discharged from the base oil discharge portion 7a penetrates through the base oil permeating means, moves to the bearing inner ring side without waste, and can reliably contribute to lubrication. Other configurations are the same as those of the first embodiment, and the same operations and effects as those of the first embodiment are achieved.

Next, a third embodiment of the present invention will be described with reference to FIG.
In the third embodiment, an inner diameter side pocket portion 5b having a larger diameter than the reference diameter D1 of the pocket portion 5a of the retainer 5 is provided on the inner diameter surface of the retainer 5. That is, as a cage shape satisfying a relationship of (inner diameter side pocket diameter D2 of inner diameter side pocket portion 5b)> (reference diameter D1) in a cross section obtained by cutting the pocket portion 5a of the retainer 5 along a so-called axial plane. Yes.
In this case, the air flow that has carried the base oil is prevented from moving away from the rolling element 3 from between the slope of the inner ring inclined portion CB and the nozzle inner diameter side inclined surface 15, and the base oil is captured by the inner diameter side pocket portion 5b. It can be reliably supplied to the rolling element 3 or the raceway surface 2a. Other configurations are the same as those of the first embodiment, and the same operations and effects as those of the first embodiment are achieved.

  FIG. 10 is a cross-sectional view showing an example in which an angular ball bearing that supports the machine tool spindle is used on the vertical axis. As shown in FIG. 10, it is an angular ball bearing provided in the vertical axis | shaft 17, Comprising: You may provide the grease reservoir 4 in the upper part of this angular ball bearing. In this case, the base oil separated from the grease reservoir 4 can be naturally moved to the bearing side by the action of gravity and supplied to the raceway surface 1a. Therefore, a means for forcibly conveying the base oil is not required, and the structure can be simplified. Accordingly, the manufacturing cost can be reduced.

FIG. 11 is a sectional view of a rolling bearing according to the fourth embodiment of the present invention.
In each said embodiment, although the example which used the angular ball bearing as a rolling bearing was shown, as shown in FIG. 11, a cylindrical roller bearing is applicable. Even in this case, the same operations and effects as the above-described embodiments can be obtained.
Although not shown, various rolling bearings such as a tapered roller bearing and a deep groove ball bearing are applicable.

It is sectional drawing of the rolling bearing which concerns on 1st Embodiment of this invention. It is sectional drawing which expands and represents the principal part of the rolling bearing. (A) It is sectional drawing which formed the groove | channel in the inner ring inclination part of the rolling bearing, (B) The top view which fractures | ruptures and shows the principal part of the inner ring inclination part. It is a top view at the time of giving the angle with respect to the axial direction the groove | channel of an inner ring inclination part according to the modification which changed the rolling bearing which concerns on 1st Embodiment partially. It is a top view at the time of making the groove | channel of an inner ring inclination part curved according to the same modified form. It is a top view at the time of forming the groove | channel of the inner ring inclination part helically according to the same modification. (A) Sectional drawing of the principal part at the time of forming a groove | channel in the inner diameter side slope of the nozzle in the rolling bearing which concerns on 1st Embodiment, (B) The bottom face which looked at the inner diameter side slope of the same nozzle from the radial direction inner side FIG. It is sectional drawing of the rolling bearing which concerns on 2nd Embodiment of this invention. It is sectional drawing of the rolling bearing which concerns on 3rd Embodiment of this invention. It is sectional drawing showing the example which used the angular ball bearing which supports a machine tool main axis | shaft with a vertical axis | shaft. It is sectional drawing of the rolling bearing which concerns on 4th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Inner ring 1a ... Race surface 2 ... Outer ring 2a ... Race surface 2h ... Outer ring back surface 3 ... Rolling element 4 ... Grease reservoir 5 ... Retainer 5b ... Inner diameter side pocket part CB ... Inner ring inclined part CB1 ... Groove 7 ... Nozzle 7a ... Base Oil discharge part 13ba ... groove 15 ... nozzle inner diameter side slope 16 ... base oil permeation means 17 ... vertical axis

Claims (9)

In a rolling bearing having an inner ring, an outer ring, and a plurality of rolling elements interposed between raceway surfaces of these inner and outer rings,
The outer ring portion of the inner ring is provided with an inner ring inclined portion having a larger diameter from the end surface side of the inner ring toward the raceway side of the inner ring,
A grease reservoir disposed adjacent to one axial direction of the bearing end surface on the side having the inner ring inclined portion;
A nozzle that protrudes from the grease reservoir and covers the outer periphery of the inclined portion of the inner ring, the nozzle including a base oil discharge part that exudes the base oil of grease; and
A rolling bearing characterized by comprising:   2. The rolling ball bearing according to claim 1, wherein the angular ball bearing is provided with the grease reservoir adjacent to a rear surface of the outer ring of the angular ball bearing.   The rolling ball bearing according to claim 2, wherein the angular ball bearing is provided on a vertical axis, and the grease reservoir is provided on an upper portion of the angular ball bearing.   The rolling bearing according to any one of claims 1 to 3, wherein a brush-like or cloth-like base oil permeating means that permeates the base oil is provided in the vicinity of the base oil discharge portion of the nozzle.   5. The rolling bearing according to claim 1, wherein a groove that guides the base oil discharged from the base oil discharge portion to the raceway surface of the inner ring is formed in the inner ring inclined portion. 6.   6. The nozzle according to claim 1, wherein the nozzle has a nozzle inner diameter side inclined surface substantially parallel to the inclined surface of the inner ring inclined portion, and discharge from the base oil discharge portion to the nozzle inner diameter side inclined surface. A rolling bearing with a groove that guides the base oil to the vicinity of the rolling elements.   7. The nozzle according to claim 1, further comprising: a holder that holds the plurality of rolling elements, wherein the nozzle is more than an axial distance between the center of the rolling element and a pocket inner diameter portion of the holder. A rolling bearing in which the axial distance between the tip of the roller and the center of the rolling element is small.   In any 1 item | term of Claim 1 thru | or 7, It has a holder | retainer which hold | maintains these rolling elements, and it is larger diameter than the reference | standard diameter of the pocket part of the holder | retainer on the internal diameter surface of this holder | retainer. A rolling bearing provided with an inner diameter side pocket.   9. The rolling bearing according to claim 1, wherein the rolling bearing is an angular ball bearing that supports the main spindle of the machine tool.

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