JP2009144781A - Rolling bearing and rolling bearing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing and a rolling bearing device capable of preventing the occurrence of seizure in a cage, furthermore, capable of preventing the occurrence of waste of lubricating oil, even if the quantity of lubricating oil is little. <P>SOLUTION: This rolling bearing has an inner ring 2 having an inner ring raceway surface 2a, an outer ring forming a shoulder part 3b on one side in the axial direction of an outer ring raceway surface 3a, a plurality of rolling elements 4 rolling between the inner ring raceway surface 2a and the outer ring raceway surface 3a, and the cage 5 holding the plurality of rolling elements 4 at a predetermined interval in the peripheral direction and having a guide object surface 5c opposed so as to be capable of slidingly contacting with the shoulder part 3b of the outer ring 3. Rotation of the cage 5 is guided when the guide object surface 5c of the cage 5 slidingly contacts with a guide surface 3c of the shoulder part 3b of the outer ring 3. A guiding clearance S being an interval in the diameter direction between the guide surface 3c of the shoulder part 3b of the outer ring 3 and the guide object surface 5c of the cage 5 gets larger as approaching the rolling elements 4. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a rolling bearing device that is lubricated by lubricating oil supplied from a rolling bearing and an oil supply means.

Conventionally, as an angular ball bearing having an inner ring, an outer ring, a ball as a rolling element disposed between them, and a cage for holding the ball, one shoulder of the outer ring and the outer circumference of the cage A so-called outer ring guide type in which rotation of the cage is guided by sliding contact is provided (see Patent Document 1).
On the other hand, in order to supply a necessary amount of lubricating oil as needed, the rolling bearing has an oil supply unit having a pump for discharging the lubricating oil and a tank for storing the lubricating oil. A rolling bearing device has been proposed in which lubricating oil is intermittently supplied in small amounts (see Patent Document 2).

JP 2004-347001 A JP 2004-108388 A

In the angular ball bearing described in Patent Document 1, if the amount of lubricating oil applied in advance is small, poor lubrication occurs at the sliding contact portion between the shoulder portion of the outer ring and the outer peripheral surface of the cage, and the cage is seized. On the other hand, when the amount of the lubricating oil is excessive, there is a problem that the lubricating oil is wasted by surplus lubricating oil flowing out of the bearing. Further, in the rolling bearing device described in Patent Document 2, when an outer ring guide type angular ball bearing is used as the rolling bearing, the same problem as described above may occur.
The present invention has been made in view of such circumstances, and even if the amount of lubricating oil is small, it is possible to prevent seizure from occurring in the cage, and in turn, waste of the lubricating oil is caused. An object of the present invention is to provide a rolling bearing and a rolling bearing device that can be prevented.

  The rolling bearing of the present invention has an inner ring having an inner ring raceway surface on the outer periphery and an outer ring raceway surface on the inner periphery, and is radially inward from the other axial side of the outer ring raceway surface on one axial side of the outer ring raceway surface. And a plurality of rolling elements rolling between the inner ring raceway surface and the outer ring raceway surface, and holding the plurality of rolling elements at a predetermined interval in the circumferential direction. A retainer having a guided surface facing the shoulder portion of the outer ring so as to be slidably contactable, and the guided surface of the retainer is in sliding contact with the guide surface of the shoulder portion of the outer ring. In the rolling bearing in which the rotation of the cage is guided, a guide gap, which is a radial interval between the guide surface of the shoulder portion of the outer ring and the guided surface of the cage, becomes larger as the rolling element approaches. It is a feature.

  In this rolling bearing, the guide gap, which is the radial distance between the guide surface of the shoulder portion of the outer ring and the guided surface of the cage, becomes larger as it approaches the rolling element. Oil can be retained. Thus, since the lubricating oil holding function of the guide gap is improved, it is possible to prevent seizure from occurring in the cage even if the amount of lubricating oil is small.

  In the rolling bearing, at least one of the guide surface of the shoulder portion of the outer ring and the guided surface of the cage is a conical surface, or a curved surface forming a differentiable curve with a cross section including its axis. There may be. Also in this case, since the function of holding the lubricating oil in the guide gap is improved, it is possible to prevent seizure from occurring in the cage even if the amount of the lubricating oil is small.

  In the rolling bearing, it is preferable that the guided surface of the cage is a cylindrical surface and the guide surface of the shoulder portion of the outer ring is a conical surface. When the guided surface of the cage is a conical surface, an undercut occurs by forming the conical surfaces on both outer peripheral surfaces of the cage to eliminate directionality, and the molded product of the cage is molded after molding. When removing from the undercut, the undercut becomes difficult to remove. However, when the guide surface of the shoulder portion of the outer ring is a conical surface, the conical surface can be easily formed by turning or grinding the shoulder portion of the outer ring.

  The rolling bearing device of the present invention includes the above rolling bearing and an oil supply unit that supplies a minute amount of lubricating oil to the rolling bearing at predetermined intervals. The oil supply unit includes a tank that stores the lubricating oil, A pump that sucks and discharges the lubricating oil in the tank; a lubricating oil discharge nozzle that is provided at a discharge port of the pump and discharges the lubricating oil; and a drive unit that drives the pump, the lubricating oil discharge nozzle Is arranged between the inner peripheral surface of the cage and the inner ring, and is open at any position in the axial range where the cage and the inner ring face each other.

  According to this rolling bearing device, since the above rolling bearing is used, the function of retaining the lubricating oil in the guide gap is improved. Thereby, even if the amount of lubricating oil is small, it is possible to prevent seizure from occurring in the cage. Due to the opening of the lubricating oil discharge nozzle at any position in the axial range where the cage and the inner ring face each other, the flow of air (air curtain) caused by the rotation of the rolling bearing is caused. It is possible to prevent the supply of the lubricating oil from being hindered, and to reliably attach the oil droplets of the lubricating oil to any one of the cage, the inner ring, and the rolling element.

  According to the rolling bearing and the rolling bearing device of the present invention, the holding function of the lubricating oil in the guide gap is improved, so that the seizure can be prevented from occurring in the cage even if the amount of the lubricating oil is small. . As a result, it is possible to prevent the lubricant from being wasted.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a schematic sectional view of a rolling bearing according to a first embodiment of the present invention. A rolling bearing 1 in FIG. 1 is an angular ball bearing including an inner ring 2, an outer ring 3, balls 4 as rolling elements arranged therebetween, and a cage 5 that holds the balls 4. .

The inner ring 2 is formed in an annular shape, and has a groove-shaped inner ring raceway surface 2a formed on the outer periphery thereof over the entire circumference.
The outer ring 3 is also formed in an annular shape, and has a groove-shaped outer ring raceway surface 3a formed on the inner periphery of the outer ring 3 over the entire circumference. In addition, a shoulder 3b is formed on one side of the outer ring raceway surface 3a in the axial direction so as to project radially inward from the other side in the axial direction of the outer ring raceway surface 3a in order to guide a cage 5 described later. Yes. The outer ring 3 is disposed concentrically with the inner ring 2.

The cage 5 is made of, for example, a synthetic resin such as a phenol resin, and a plurality of pockets 5a for receiving balls 4 are provided at equal intervals in the circumferential direction, and the entire outer peripheral surface 5b is a cylindrical surface.
The retainer 5 is disposed substantially concentrically with the inner ring 2 and the outer ring 3 between the outer peripheral surface of the inner ring 2 and the inner peripheral surface of the outer ring 3, and faces the shoulder 3 b of the outer ring 3 so as to be slidable. The guided surface 5c is provided. Then, the guided surface 5 c of the cage 5 is in sliding contact with the guide surface 3 c of the shoulder 3 b of the outer ring 3 to guide the rotation of the cage 5.
The balls 4 are accommodated in the pockets 5a of the cage 5 so as to be held at predetermined intervals in the circumferential direction, and roll between the inner ring raceway surface 2a and the outer ring raceway surface 3a.

FIG. 2 is an enlarged cross-sectional view illustrating the outer ring 3 and the cage 5. As shown in FIG. 2, the radial gap between the guide surface 3 c of the shoulder 3 b of the outer ring 3 and the guided surface 5 c of the cage 5 constitutes a guide gap S. Here, the guided surface 5c of the cage 5 is a cylindrical surface, and the radial interval S1 between the guided surface 5c of the cage 5 and the outer side end 3d of the guide surface 3c of the outer ring 3 is, for example, 0.2. ~ 0.4 mm. The guide surface 3c of the shoulder 3b of the outer ring 3 is a conical surface formed in a tapered shape so that the diameter gradually increases from the outer side end 3d to the rolling element side end 3e of the guide surface 3c. Yes. The angle θ of this conical surface is, for example, 0.1 to 1 °, and the difference between the inner diameter d1 of the rolling element side end portion 3e and the inner diameter d2 of the outer side end portion 3d of the guide surface 3c is, for example, 0.01 to It is 0.014 mm. The angle θ can be appropriately set depending on the size of the rolling bearing.
Thus, the guide gap S increases as the ball 4 that is a rolling element approaches.

  In the rolling bearing 1, the guided surface 5 c of the cage 5 is in sliding contact with the guide surface 3 c of the shoulder 3 b of the outer ring 3 to guide the rotation of the cage 5. Here, the guide gap S, which is the radial interval between the guide surface 3c of the shoulder 3b of the outer ring 3 and the guided surface 5c of the cage 5, becomes larger as the ball 4 is approached. In addition, more lubricating oil can be retained than in the past. As described above, since the lubricating oil retaining function of the guide gap S is improved, it is possible to prevent seizure from occurring in the cage 5 even when the amount of lubricating oil is small. Conventionally, the retainer 5 vibrates with the rotation of the retainer 5, and the outer peripheral surface 5 b is inclined with respect to the axis of the outer ring 3, so that the cylindrical portion of the shoulder 3 b formed on one side of the outer ring 3. The contact surface pressure was locally increased on the ball 4 side when the outer peripheral surface of the cage 5 hit the surface obliquely. However, by setting the guide gap S as described above, the cage 5 is attached to the outer ring 3. Surface contact with the shoulder portion 3b is facilitated, and the local high surface pressure applied to the cage 5 is alleviated. Thereby, seizure of the cage 5 can be more effectively prevented. And since the amount of lubricating oil supplied is small, torque fluctuations of the rolling bearing 1 can be reduced, and leakage of lubricating oil to the outside of the bearing can be prevented. As a result, it is possible to prevent the lubricant from being wasted.

  From these facts, when the rolling bearing 1 is oil-lubricated or oil-air lubricated, the rolling bearing 1 can be lubricated with a small amount of lubricating oil.

FIG. 3 is a schematic cross-sectional view of a rolling bearing device according to the present invention.
A rolling bearing device 10 in FIG. 3 includes the above-described rolling bearing 1 and an oil supply unit K. The rolling bearing 1 is lubricated by supplying a small amount of lubricating oil into the bearing at predetermined intervals by the oil supply unit K. Here, “a trace amount” of lubricating oil means that the amount of lubricating oil supplied at a time is on the order of nanoliters (nL).
FIG. 4 is a side view of the rolling bearing device 10 in FIG. 3 for explaining the oil supply unit K. FIG.

The oil supply unit K includes, for example, a tank 6 for storing lubricating oil, a pump 7 that sucks and discharges the lubricating oil in the tank 6, and a lubricating oil discharge nozzle that is provided at a discharge port of the pump 7 and discharges the lubricating oil. 8 and a drive unit (not shown) for driving the pump 7.
In this embodiment, as shown in FIGS. 3 and 4, the tank 6 and the pump 7 are built in the rolling bearing 1.

  That is, the inner ring 2 and the outer ring 3 are provided with oil supply unit installation extensions 2 b and 3 f in addition to the portion for holding the ball 4, and the pump 7 is provided with the oil supply unit installation extension of the outer ring 3. It is detachably attached to the inner peripheral surface of 3f. The tank 6 has an arc shape when viewed from the axial direction, and is detachably attached to the inner peripheral surface of the oil supply unit installation extension 3f of the outer ring 3 so as to be adjacent to the pump 7 in the circumferential direction. It is connected to the pump 7 by a conduit 9.

The pump 7 is a diaphragm pump that sucks the lubricating oil in the tank 6 into the chamber of the pump 7 and discharges it from the lubricating oil discharge nozzle 8 by reciprocating a diaphragm as a driven part by a piezoelectric element.
The lubricating oil discharge nozzle 8 is disposed between the inner peripheral surface 5d of the cage 5 and the inner ring 2, and is open at any position in the axial range where the cage 5 and the inner ring 2 face each other. A small amount of the lubricating oil in 6 is supplied to the vicinity of the inner ring raceway surface 2 a of the inner ring 2 and the balls 4. The opening of the lubricating oil discharge nozzle 8 at the above position prevents the supply of the lubricating oil from being hindered due to the flow of air (air curtain) generated by the rotation of the rolling bearing 1, and prevents the lubricating oil from flowing. Oil droplets can be reliably attached to any one of the cage 5, the inner ring 2, or the balls 4.
The driving unit is provided with a power source battery (or generator) or a transformer circuit of an external power source, a pump control circuit, and the like. The pump 7 is driven by the voltage signal from the driving unit, and the pump 7 is connected from the tank 6. By sucking the lubricating oil, the lubricating oil is discharged from the lubricating oil discharge nozzle 8 toward the balls 4 and the inner raceway surface 2a.

  Thereby, between the ball 4 and the inner and outer ring raceway surfaces 2a and 3a, between the guided surface 5c of the cage 5 and the guide surface 3c of the outer ring 3, and between the ball 4 and the pocket 5a. Lubricated.

  As the type of base oil in the lubricating oil, any of ester, ether, fluorine, silicone, and synthetic hydrocarbon may be used. Examples of lubricating oils include fluorinated polymer oils, fluorinated polyether oils, alkyl diphenyl ether oils, polyphenyl ether oils, polyol ester oils, and polyalphaolefin oils. These may be used alone or in combination of two or more. Can be used.

According to this rolling bearing device 10, since the above-described rolling bearing 1 is used, the lubricating oil discharged from the lubricating oil discharge nozzle 8 is retained more in the guide gap S between the outer ring 3 and the cage 5. Therefore, the lubricating oil retention function is improved. Thereby, even if there is little quantity of lubricating oil, it can prevent that the holder | retainer 5 generate | occur | produces and can prevent the waste of lubricating oil.
Thus, even if the amount of lubricating oil is small, it becomes possible to lubricate the inside of the bearing, so that the interval for supplying the lubricating oil to the tank 6 of the rolling bearing device 10 can be lengthened, and thereby the rolling bearing. The maintenance frequency of the apparatus 10 can be reduced.

The present invention is not limited to the above-described embodiment, and can be appropriately changed within the scope of the present invention.
In the rolling bearing 1 according to the first embodiment, the guide surface 3c of the outer ring 3 is a conical surface and the guided surface 5c of the cage 5 is a cylindrical surface, but the present invention is not limited to this. For example, the guide surface 3c of the outer ring 3 may be a cylindrical surface, and the guided surface 5c of the cage 5 may be a conical surface. It is also possible to make both sides conical. Further, instead of a conical surface, a curved surface forming a differentiable curve with a cross section including the axis may be used.

In the rolling bearing device 10, the tank 6 and the pump 7 of the oil supply unit K are built in the rolling bearing 1. The tank 6 and the pump 7 are attached to the outside of the rolling bearing 1, for example, the rolling bearing 1. It may be attached to an appropriate position such as a housing. Further, as shown in FIG. 5, all the components of the oil supply unit K may be provided outside the rolling bearing 1, or all the components of the oil supply unit K can be incorporated in the rolling bearing 1. It is.
The oil supply unit K of the rolling bearing device 10 only needs to supply a small amount of lubricating oil inside the bearing, and is not limited to the configuration of the second embodiment. For example, an oil mist lubrication device, an oil / air lubrication device, or an oil jet lubrication device may be used as long as a minute amount of lubricating oil can be supplied.

  Next, the present invention will be described in more detail based on examples. However, the present invention is not limited to such examples.

Example 1
An angular ball bearing having an inner diameter (D1) of 70 mm, an outer diameter (D2) of 110 mm, and an assembly width (W) of 20 mm shown in FIG. In this sample bearing 21, the cage 25 is guided by one shoulder portion 23b of the outer ring 23, and the guide surface 23c of the shoulder portion 23b is a conical surface, and the rolling element side end of the guide surface 23c. The difference S2 between the inner diameter (95.212 mm) of the portion 23e and the inner diameter (95.2 mm) of the outer end 23d is 0.012 mm, and the angle θ of the guide surface 23c of the outer ring 23 is 0.17 °.

The sample bearing 21 is cleaned and degreased, and 10 μL of the spindle oil (VG22), which is 10 μL on the ball 24 and 10 μL on the guided surface 25b of the cage 25 and the guide surface 23c of the outer ring 23, is used as an initial lubricating oil by a microsyringe from the outside. Applied.
The inner ring spacer 32 and the inner ring 22 assembled with the balls 24 and the cage 25 are fitted into the outer peripheral surface of the shaft (not shown), and the outer ring spacer 33 and the outer ring 23 are fitted into the inner peripheral surface of the housing (not shown), thereby providing a 21 was assembled to the shaft and the housing, and a preload of 1300 N was applied to the sample bearing 21.

  On the inner periphery of the outer ring spacer 33, a pump 37 connected to the lubricating oil discharge nozzle 38, a conduit (not shown) communicating with the pump 37, and a tank (not shown) communicating with the conduit are provided. The lubricating oil discharge nozzle 38 is a space between the inner circumferential surface of the cage 25 and the outer circumferential surface of the inner ring 22, and opens within a range where the inner circumferential surface of the cage 25 and the outer circumferential surface of the inner ring 22 overlap in the radial direction. is doing. The lubricating oil discharge nozzle 38 is disposed in non-contact with the cage 25 and the inner ring 22. The lubricating oil discharge nozzle 38 has a cylindrical shape and extends from the pump 37 in the axial direction. One end of the yarn 40 is fixed to the tip of the lubricating oil discharge nozzle 38, and the yarn 40 has a length that allows the other end side to contact the ball 24.

  The other end side of the yarn 40 is in contact with the ball 24 directly or via the supplied lubricating oil. As shown in FIG. 7, the yarn 40 is bonded and fixed to the opening of the lubricating oil discharge nozzle 38 at intervals of 3 equally spaced in the circumferential direction (every 120 °). When the pump 37 is driven by a drive unit (not shown), the lubricating oil in the tank is sucked, and the lubricating oil supplied from the pump 37 is directly from the opening of the lubricating oil discharge nozzle 38 or through the yarn 40, the balls 24, It is supplied to the inner ring 22 and the cage 25. By having the thread 40, the lubricating oil can be supplied to the balls 24 better than when the thread 40 is not present.

  After that, spindle oil (VG22) is discharged from the opening of the lubricating oil discharge nozzle 38 directly or along the thread 40 to the ball 24 at 20 nL / min, and rotated for 8 hours at a rotational speed of 20000 r / min while cooling the jacket. Judgment was made. The criterion for pass / fail judgment was pass (◯) if the vibration value was less than 3 times the initial vibration value, and reject (x) if it was 3 times or more. When the vibration value tripled within 8 hours, the test was stopped at that time. The results are shown in Table 1.

Example 2
The test was performed in the same manner as in Example 1 except that the sample bearing 21 was rotated without cooling the jacket. The results are shown in Table 1.

Comparative Example 1
A test was performed in the same manner as in Example 1 except that the guide surface 23c of the outer ring 23 was a cylindrical surface, and the sample bearing 21 in which the inner diameter of the guide surface 23c was 95.2 mm was used. The results are shown in Table 1.

Comparative Example 2
The test was performed in the same manner as in Example 1 except that the guide surface 23c of the outer ring 23 was a cylindrical surface and the inner surface of the guide surface 23c was rotated without cooling the jacket using the sample bearing 21. It was. The results are shown in Table 1.

  From the results shown in Table 1, the example in which the guide surface of the outer ring is a conical surface is compared with the comparative example in which the guide surface of the outer ring is the same cylindrical surface as before, when the same amount of lubricating oil is supplied. It can be seen that it can rotate for a very long time.

It is a schematic sectional drawing which shows the rolling bearing which concerns on the 1st Embodiment of this invention. It is an expanded sectional view explaining the outer ring | wheel and holder | retainer of FIG. It is a schematic sectional drawing which shows the rolling bearing apparatus which concerns on this invention. It is a side view of the rolling bearing apparatus of FIG. It is a schematic sectional drawing explaining the other attachment position of an oil supply unit. It is a schematic sectional drawing of the sample bearing used in an Example. It is an expansion perspective view explaining the lubricating oil discharge nozzle and thread | yarn of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rolling bearing 2 Inner ring 3 Outer ring 4 Rolling element (ball)
5 Cage 6 Tank 7 Pump 8 Lubricating oil discharge nozzle 9 Conduit 10 Rolling bearing device K Lubrication unit S Guide gap

Claims (4)

An inner ring having an inner ring raceway surface on the outer periphery;
An outer ring having an outer ring raceway surface on the inner periphery, and having a shoulder formed radially inward from the other axial side of the outer ring raceway surface on one axial side of the outer ring raceway surface;
A plurality of rolling elements rolling between the inner ring raceway surface and the outer ring raceway surface;
Holding the plurality of rolling elements at a predetermined interval in the circumferential direction, and having a guided surface facing the shoulder of the outer ring so as to be slidable,
In a rolling bearing in which rotation of the cage is guided by a guided surface of the cage slidingly contacting a guide surface of a shoulder portion of the outer ring,
A rolling bearing, characterized in that a guide gap, which is a radial distance between a guide surface of a shoulder portion of the outer ring and a guided surface of the cage, increases as the rolling element approaches.   The guide surface of the shoulder portion of the outer ring and the guided surface of the cage are conical surfaces, or curved surfaces forming a differentiable curve with a cross section including an axis thereof. The rolling bearing described.   The rolling bearing according to claim 1 or 2, wherein a guided surface of the cage is a cylindrical surface, and a guide surface of a shoulder portion of the outer ring is a conical surface. The rolling bearing according to any one of claims 1 to 3, and an oil supply unit that supplies a minute amount of lubricating oil to the rolling bearing at predetermined intervals,
The oil supply unit includes a tank for storing lubricating oil, a pump that sucks and discharges the lubricating oil in the tank, a lubricating oil discharge nozzle that is provided at a discharge port of the pump and discharges lubricating oil, and the pump And a drive unit for driving
The lubricating oil discharge nozzle is disposed between the inner peripheral surface of the cage and the inner ring, and is open at any position in the axial range where the cage and the inner ring face each other. A rolling bearing device that is characterized.

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