JP2018040469A - Cooling structure of bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling structure of a bearing device capable of efficiently cooling a bearing or the like even with few compressed air and suppressing the use amount of the compressed air.SOLUTION: A bearing device J is provided with a stationary-side spacer 4 and a rotation-side spacer 5 on a stationary-side bearing ring 2 and a rotation-side bearing ring 3 opposed to the inside and outside of a rolling bearing 1, respectively in adjacent to each other. The stationary-side bearing ring 2 and the stationary-side spacer 3 are disposed on a stationary member 6, and the rotation-side bearing ring 3 and the rotation-side spacer 5 are disposed on a rotation member 7. An annular stationary-side recessed part 13 is provided on a peripheral surface on which spacers in the stationary-side spacer 4 face each other, and an annular rotation-side recessed part 14 is provided at an axial position facing the stationary-side recessed part 13 in a peripheral surface on which spacers in the rotation-side spacer 5 face each other. A nozzle hole 15 for discharging compressed air A from an outlet 15a opened in a bottom surface of the stationary-side recessed part 13 toward a bottom surface of the rotation-side recessed part 14 is provided obliquely forward in a rotation direction of the rotation-side spacer 5.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a cooling structure for a bearing device, for example, a main shaft of a machine tool and a cooling structure for a bearing incorporated in the main shaft.

  In a spindle device of a machine tool, it is necessary to suppress the temperature rise of the device to be small in order to ensure machining accuracy. However, recent machine tools have a tendency to increase the speed in order to improve the processing efficiency, and the heat generated from the bearing supporting the main shaft is also increasing as the speed increases. In addition, so-called motor built-in types in which a driving motor is incorporated in the apparatus are becoming more and more a cause of heat generation of the apparatus.

  The rise in the temperature of the bearing due to heat generation results in an increase in preload, and we want to suppress it as much as possible in consideration of higher speed and higher accuracy of the spindle. As a method for suppressing the temperature rise of the main shaft device, there is a method of cooling the shaft and the bearing by sending cooling air to the bearing (for example, Patent Documents 1 and 2). In Patent Documents 1 and 2, cooling of the shaft and the bearing is performed by injecting cold air into the space between the two bearings at an angle in the rotational direction to form a swirling flow.

JP 2000-161375 A Japanese Patent Laying-Open No. 2015-183738

  In machine tools, compressed air is used for air seals for preventing foreign matter from entering the spindle, air oil for bearing lubrication, oil mist, and the like. These compressed air is produced by a compressor. Usually, one compressor is used for one machine tool. When cooling a bearing, a shaft, or the like with compressed air, compressed air generated by the compressor is used as cooling air for cooling.

  In cooling with compressed air as in Patent Document 1, the cooling effect increases as the amount of compressed air supplied increases. However, in order to increase the supply amount of compressed air, a compressor having a larger capacity must be employed. For this reason, when the cooling effect is improved, the machine tool is increased in size and the energy consumption is increased.

  Patent document 2 is a proposal made in order to solve the said subject. That is, as shown in FIG. 12, in a bearing device J in which an outer ring spacer 104 and an inner ring spacer 105 are provided between a pair of rolling bearings 101, 101, an annular recess 113 is formed on the inner peripheral surface of the outer ring spacer 104. The compressed air A for cooling is blown toward the outer peripheral surface of the inner ring spacer 105 from the nozzle hole 115 provided in the outer ring spacer 104. The compressed air A is discharged from the narrow nozzle hole 115 into the wide space 120 mainly composed of the recessed portion 113, so that the compressed air A is adiabatically expanded, and the temperature of the compressed air A is lowered and the flow velocity is increased. By blowing this compressed air A onto the inner ring spacer 105, the inner ring spacer 105 and the rolling bearing 101 are efficiently cooled.

  Thus, according to the structure of patent document 2, since the cooling effect increases, it becomes possible to suppress the temperature rise of a bearing etc. with less compressed air than the conventional one. However, it is desired to cool the bearings and the like with less compressed air.

  An object of the present invention is to provide a cooling structure for a bearing device that can efficiently cool a bearing or the like with a small amount of compressed air and can suppress the amount of compressed air used.

A cooling structure for a bearing device according to the present invention includes a stationary spacer and a rotating spacer adjacent to a stationary bearing ring and a rotating bearing ring facing the inside and outside of a rolling bearing, respectively. The fixed side spacer is installed on a fixed member of a fixed member and a rotating member, and the rotating side race and the rotating side spacer are installed on a rotating member of the fixed member and the rotating member. In the bearing device,
An axis that is provided with an annular fixed recess on the circumferential surface of the fixed spacer facing each other and that faces the fixed recess on the circumferential surface of the rotating spacer facing each other. An annular rotation-side recess is provided in the direction position, and a nozzle hole that discharges compressed air from an outlet that opens to the bottom surface of the fixed-side recess to the bottom surface of the rotation-side recess is formed on the rotation-side spacer. It is provided to be inclined forward in the rotational direction.
For example, the stationary side race is an outer race, and the rotation side race is an inner race. In this case, the fixing member and the rotating member are, for example, a housing and a shaft, respectively.

  According to this configuration, the compressed air for cooling is discharged from the nozzle hole provided in the fixed side spacer toward the bottom surface of the rotation side recess provided in the rotation side spacer. The compressed air is adiabatically expanded by being discharged from a narrow nozzle hole into a wide space mainly composed of the fixed side recess and the rotation side recess. This adiabatic expansion increases the flow rate of the compressed air and decreases the temperature. Therefore, the rotating side spacer is efficiently cooled. Not only is the recessed part provided in the fixed spacer as in the past, but the recessed part is also provided in the rotating spacer so that the space for compressed air discharge is wider than in the conventional configuration. It has become. As a result, the adiabatic expansion of the compressed air is promoted, the flow rate of the compressed air is further increased, and the temperature is lowered, so that the cooling effect is further improved.

  Further, since the nozzle hole provided in the fixed side spacer is inclined forward in the rotation direction of the rotation side spacer, the compressed air discharged from the nozzle hole swirls along the peripheral surface of the rotation side spacer. However, it flows in the axial direction and is discharged to the outside of the bearing. Since the compressed air swirls, it takes a longer time for the compressed air to be in contact with the peripheral surface of the rotating side spacer than in the case where it flows straight in the axial direction, and the rotating side spacer can be cooled more efficiently.

  Thus, by efficiently cooling the rotating side spacer, the rotating side bearing ring and the rotating shaft of the rolling bearing can be effectively cooled via the rotating side spacer. For this reason, the usage-amount of compressed air can be suppressed.

In this invention, it is preferable that the axial length of the rotation-side recess is at least twice the diameter of the nozzle hole.
When the axial length of the rotation-side recess is smaller than twice the hole diameter of the nozzle hole, the compressed air does not flow well into the rotation-side recess, and the compressed air discharged from the nozzle hole can be sufficiently adiabatically expanded. Can not.

In this invention, it is preferable that the radial depth of the rotation-side recess is in the range of 10% to 50% of the radial thickness of the rotation-side spacer.
When the radial depth of the rotation-side recess is less than 10% of the radial thickness of the rotation-side spacer, the volume of the rotation-side recess is small and the volume of compressed air cannot be increased sufficiently. In addition, if it exceeds 50%, the radial thickness of the rotating side spacer becomes too thin, and there is a risk that the rotating side spacer may be damaged by the axial load acting when the bearing is incorporated into the shaft or during operation. .

In the present invention, a cross-shaped or streak-shaped recess may be formed on the bottom surface of the rotation-side recess. In addition, a plurality of circumferential grooves may be provided on the bottom surface of the rotation side recess.
In these cases, since the bottom surface of the rotation-side recess becomes an uneven surface and the surface area of the bottom surface increases, heat exchange between the rotation-side spacer and the compressed air is efficiently performed, and the cooling effect is further enhanced.

In this invention, the fixed side spacer includes a fixed side spacer body in which the nozzle hole is formed and a lubricating oil hole forming member in which a lubricating oil hole for supplying lubricating oil to the rolling bearing is formed. The peripheral surface of the fixed side spacer body may be the bottom surface of the fixed side recess, and the side surface of the lubricating oil hole forming member may be the side wall surface of the fixed side recess.
As described above, when the fixed-side recessed portion is configured by the peripheral surface of the fixed-side spacer body and the side surface of the lubricating oil hole forming member, the fixed-side recessed portion is formed only by combining the fixed-side spacer main body and the lubricating oil hole forming member. Therefore, it is not necessary to process the fixed side recess.

  A cooling structure for a bearing device according to the present invention includes a stationary spacer and a rotating spacer adjacent to a stationary bearing ring and a rotating bearing ring facing the inside and outside of a rolling bearing, respectively. The fixed side spacer is installed on a fixed member of a fixed member and a rotating member, and the rotating side race and the rotating side spacer are installed on a rotating member of the fixed member and the rotating member. In the bearing device, an annular fixed-side dent is provided on a circumferential surface of the fixed-side spacer facing each other, and the fixed-side dent on the circumferential surface of the rotating-side spacer facing each other. An annular rotation-side recess is provided at an axial position facing the nozzle, and a nozzle hole that discharges compressed air from the outlet opening at the bottom surface of the fixed-side recess to the bottom surface of the rotation-side recess has the rotation. Side spacer Since provided with an inclination toward the front of the rotational direction, and can efficiently cool the bearing or the like even with a small compressed air, it is possible to suppress the amount of compressed air.

It is sectional drawing of the machine tool spindle apparatus provided with the cooling structure of the bearing apparatus which concerns on one Embodiment of this invention. It is an expanded sectional view of the principal part of the cooling structure of the bearing device. FIG. 3 is a sectional view taken along line III-III in FIG. 1. It is explanatory drawing for comparing the width of the space where compressed air is discharged. It is sectional drawing of the principal part of the cooling structure of the bearing apparatus which concerns on different embodiment of this invention. It is sectional drawing of the principal part of the cooling structure of the bearing apparatus which concerns on further different embodiment of this invention. It is sectional drawing of the principal part of the cooling structure of the bearing apparatus which concerns on further different embodiment of this invention. It is sectional drawing of the principal part of the cooling structure of the bearing apparatus which concerns on further different embodiment of this invention. It is sectional drawing of the principal part of the cooling structure of the bearing apparatus as a comparative example. It is sectional drawing of the principal part of the cooling structure of the bearing apparatus as a different comparative example. It is sectional drawing of the principal part of the cooling structure of the bearing apparatus as another comparative example. It is sectional drawing of the principal part of the cooling structure of the conventional bearing apparatus.

A cooling structure for a bearing device according to an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a cross-sectional view of a machine tool spindle device provided with a cooling structure for the bearing device. In this example, it is applied to a spindle device of a machine tool, but is not limited to the spindle device of a machine tool.

  The bearing device J includes two rolling bearings 1 and 1 arranged in the axial direction, and an outer ring spacer 4 and an inner ring spacer 5 are respectively provided between the outer rings 2 and 2 and the inner rings 3 and 3 of the respective rolling bearings 1 and 1. Intervene. The outer ring 2 and the outer ring spacer 4 are installed in the housing 6, and the inner ring 3 and the inner ring spacer 5 are fitted to the main shaft 7. The rolling bearing 1 is an angular ball bearing, and a plurality of rolling elements 8 are interposed between the raceway surfaces of the outer ring 2 and the inner ring 3. The rolling elements 8 are held by the cage 9 at an equal circumference. The two rolling bearings 1 and 1 are arranged in combination with each other on the back surface, and are used by setting the initial preload of each rolling bearing 1 and 1 depending on the width dimension difference between the outer ring spacer 4 and the inner ring spacer 5.

  In this embodiment, the rolling bearing 1 is used for inner ring rotation. Therefore, the outer ring 2 and the inner ring 3 are the “fixed side race ring” and “rotation side race ring”, respectively, and the outer ring spacer 4 and the inner ring spacer 5 are “fixed side spacer” and “rotation side”. It ’s a “space”. The main shaft 7 is a “rotating member” and the housing 6 is a “fixing member”. The same applies to other embodiments described later.

  The outer rings 2, 2 and the outer ring spacer 4 are, for example, a clearance fit with respect to the housing 6, and are positioned in the axial direction by the step portion 6 a of the housing 6 and the end surface cover 40. The inner rings 3 and 3 and the inner ring spacer 5 are, for example, an interference fit with respect to the main shaft 7 and are positioned in the axial direction by the positioning spacers 41 and 42 on both sides. Note that the positioning spacer 42 on the left side of the figure is fixed by a nut 43 screwed onto the main shaft 7.

The cooling structure will be described.
As shown in FIG. 2, the outer ring spacer 4 includes an outer ring spacer main body 11 that is a stationary side spacer main body, and ring-shaped lubricating oil hole forming members 12 and 12 that are separate members from the outer ring spacer main body 11. And have. The outer ring spacer body 11 is formed in a substantially T-shaped cross section, and the lubricating oil hole forming members 12 and 12 are fixed in symmetrical arrangement on both sides in the axial direction of the outer ring spacer body 11. FIG. 2 is a partially enlarged view of FIG. 1 in FIG. However, the cut surface of one rolling bearing 1 differs in FIG. 1 and FIG.

  The inner diameter dimension of the outer ring spacer body 11 is larger than the inner diameter dimension of the lubricating oil hole forming members 12, 12. As a result, on the inner peripheral surface of the outer ring spacer 4, the fixed recess 13 formed by the inner peripheral surface of the outer ring spacer main body 11 and the side surfaces of the lubricating oil hole forming members 12 and 12 following the inner peripheral surface. Is formed. The inner peripheral surface of the outer ring spacer body 11 is the bottom surface of the fixed-side recess portion 13, and the side surfaces of the lubricating oil hole forming members 12, 12 are side wall surfaces of the fixed-side recess portion 13. When the fixed recess 13 is formed by the inner peripheral surface of the outer ring spacer body 11 and the side surfaces of the lubricating oil hole forming members 12, 12, the outer ring spacer body 11 and the lubricating oil hole forming members 12, 12 are combined. Since only the fixed-side recess 13 is formed, the processing of the fixed-side recess 13 is unnecessary.

  The fixed side recess 13 is an annular groove having a substantially rectangular cross section. The inner diameter end portions 12a and 12a on the side surfaces of the lubricating oil hole forming members 12 and 12 are notched obliquely so that the distance between them increases toward the inner diameter side. The inner peripheral surface of the outer ring spacer 4 other than the fixed recess 13, that is, the inner peripheral surface of the lubricating oil hole forming members 12 and 12, and the outer peripheral surface of the inner ring spacer 5 are interposed via a minute radial clearance δa. Opposite.

  On the outer peripheral surface of the inner ring spacer 5, an annular rotation side recess 14 is provided so as to face the inner peripheral surface of the outer ring spacer main body 11. The rotation side recess 14 is an annular groove having a rectangular cross section. The axial width Y of the rotation-side recess 14 is the same as the inner peripheral surface of the outer ring spacer body 11. Further, the depth Z of the rotation-side recess 14 is in the range of 10% to 50% of the radial thickness T of the inner ring spacer 5.

  The outer ring spacer body 11 is provided with a nozzle hole 15 for discharging compressed air A for cooling toward the bottom surface of the rotation side recess 14 of the inner ring spacer 5. The outlet 15 a of the nozzle hole 15 is open to the bottom surface of the rotation side recess 13 of the outer ring spacer 4. In this example, a plurality of (for example, three) nozzle holes 15 are provided, and each of them is arranged in a uniform manner in the circumferential direction.

  As shown in FIG. 3, each nozzle hole 15 is inclined forward in the rotational direction of the inner ring spacer 5. That is, the position is offset from an arbitrary radial straight line L in a cross section perpendicular to the axis of the outer ring spacer 4 in a direction orthogonal to the straight line L. The reason why the nozzle hole 15 is offset is to improve the cooling effect by causing the compressed air A to act as a swirling flow in the rotation direction of the inner ring spacer 5. In FIGS. 1 and 2, the outer ring spacer 4 is indicated by a cross section passing through the center line of the nozzle hole 15.

  On the outer peripheral surface of the outer ring spacer main body 11, an introduction groove 16 for introducing the compressed air A into each nozzle hole 15 from the outside of the bearing is formed. The introduction groove 16 is provided in an intermediate portion in the axial direction on the outer peripheral surface of the outer ring spacer 4 and is formed in an arc shape communicating with each nozzle hole 15. The introduction groove 16 is provided on the outer peripheral surface of the outer ring spacer main body 11 over an angular range α indicating most of the circumferential direction except a circumferential position where an air oil supply path (not shown) described later is provided. . As shown in FIG. 1, a compressed air introduction path 45 is provided in the housing 6, and the introduction groove 16 communicates with the compressed air introduction path 45. An air supply device (not shown) for supplying the compressed air A to the compressed air introduction hole 45 is provided outside the housing 5.

The lubrication structure will be described.
As shown in FIG. 1, the outer ring spacer 4 has the lubricating oil hole forming members 12 and 12 for supplying lubricating oil into the bearing. In this example, air oil is used as the lubricating oil. Each lubricating oil hole forming member 12 has a base 12a whose inner peripheral surface faces the inner ring spacer 5 via the radial clearance δa, and projects outward from the base 12a in the axial direction between the outer peripheral surface of the inner ring 3. And an eaves-shaped tip portion 30 which is opposed to each other through an annular clearance δb for air oil passage. In other words, the distal end portion 30 of the lubricating oil hole forming member 12 is disposed so as to enter the bearing so as to cover the outer peripheral surface of the inner ring 3. Further, the tip end portion 30 of the lubricating oil hole forming member 12 is disposed radially inward from the inner peripheral surface of the cage 9.

As shown in FIG. 2, the lubricating oil hole forming member 12 is provided with a lubricating oil hole 31 for supplying air oil to the annular clearance δb between the lubricating oil hole forming member 12 and the outer peripheral surface of the inner ring 3. The lubricant hole 31 is inclined so as to reach the inner diameter side toward the bearing side, and an outlet is opened on the inner peripheral side of the tip portion 30. Air oil is supplied to the lubricating oil hole 31 through a lubricating oil supply path (not shown) provided in the housing 6 and the outer ring spacer main body 11. An annular recess 3 a is provided at a location on the extended line of the lubricating oil hole 31 on the outer peripheral surface of the inner ring 3.
The oil of the air oil discharged from the lubricating oil hole forming member 12 accumulates in the annular recess 3a, and this oil is centered on the bearing along the outer peripheral surface of the inner ring 3 which is an inclined surface by the centrifugal force accompanying the rotation of the inner ring 3. Guided to the side.

The exhaust structure will be described.
As shown in FIG. 1, the bearing device J is provided with an exhaust passage 46 for exhausting compressed air for cooling and air oil for lubrication. The exhaust passage 46 includes an exhaust groove 47 provided in a part of the outer ring spacer body 11 in the circumferential direction, a radial exhaust hole 48 provided in the housing 6 and communicating with the exhaust groove 47, and an axial exhaust hole 49. Have The exhaust groove 47 of the outer ring spacer body 11 is formed across a circumferential position diagonal to the position where the lubricating oil supply path is provided.

The effect | action of the cooling structure of the bearing apparatus which consists of the said structure is demonstrated.
From the nozzle hole 15 provided in the outer ring spacer 4, the compressed air A for cooling is blown toward the bottom surface of the rotation side recess 14 of the inner ring spacer 5. At this time, the compressed air A is adiabatically expanded by being discharged from the narrow nozzle hole 15 into the wide space 20 mainly composed of the fixed side recess 13 and the rotation side recess 14. Precisely, the space 20 is a combination of the fixed recess 13, the rotation recess 14, and the width of the radial clearance δa interposed between the fixed recess 13 and the rotation recess 14. Size.

  When the volume of the compressed air A in the nozzle hole 15 is V1, the temperature is T1, the volume of the compressed air in the space 20 is V2, and the temperature is T2, V1 is obtained from the equation of state of gas and the first law of thermodynamics. <V2, T1> T2. That is, in the space 20, the temperature of the compressed air A decreases and the volume increases. As the volume increases, the flow rate of the compressed air A increases. Thus, the inner ring spacer 5 is efficiently cooled by blowing the compressed air A at a low temperature and high speed onto the inner ring spacer 5.

  In the conventional cooling structure of the bearing device shown in FIG. 12, the volume of the space 120 into which the compressed air A is discharged is approximately the size of the volume of the recess 113 (FIG. 4A). On the other hand, in the cooling structure of the bearing device of FIG. 2, the volume of the space 20 (FIG. 4B) from which the compressed air A is discharged is approximately the volume of the fixed recess 13 and the volume of the rotation recess 14. It is the size which added and. When the volume of the recess 113 is the same as that of the fixed recess 13, the space 20 in the cooling structure of the bearing device in FIG. 2 is more rotationally recessed than the space 120 in the cooling structure of the bearing device in FIG. 11. Larger by 14 volumes. For this reason, the cooling structure of the bearing device of FIG. 2 has a large expansion coefficient of the compressed air A discharged from the nozzle hole 15, further promotes the temperature drop and volume increase of the compressed air A, and increases the cooling effect.

  In this embodiment, the axial width Y of the rotation-side recess 14 is the same as the inner peripheral surface of the outer ring spacer body 11, but the axial width Y of the rotation-side recess 14 is the inner width of the outer ring spacer body 11. The width may not be the same as the peripheral surface. However, even in that case, it is desirable that the axial length Y of the rotation-side recess 14 is at least twice the hole diameter D of the nozzle hole 15. As shown in FIG. 9, if the axial length Y of the rotation-side recess 14 is smaller than twice the hole diameter D of the nozzle hole 15, the compressed air A does not flow into the rotation-side recess 14 and the nozzle hole Compressed air A discharged from 15 cannot be sufficiently adiabatically expanded.

  The reason why the radial depth Z of the rotation-side recess 14 is in the range of 10% to 50% of the radial thickness T of the rotation-side spacer 5 is as follows. That is, as shown in FIG. 10, if the radial depth Z is less than 10% of the wall thickness T, the volume of the rotation-side recess 14 is small, and the volume of the compressed air A cannot be increased sufficiently. Further, as shown in FIG. 11, when it exceeds 50%, the radial thickness T of the rotating side spacer 14 becomes thin, and it is caused by the axial load acting when the rolling bearing 1 is incorporated into the main shaft 7 or during operation. There is a risk of damage to the rotary spacer 5.

  Since the nozzle hole 15 is inclined forward in the rotational direction of the inner ring spacer 5, the compressed air A discharged from the nozzle hole 15 flows in the axial direction while turning along the outer peripheral surface of the inner ring spacer 5. , And is discharged to the outside of the bearing through the exhaust passage 46. Since the compressed air A turns, it takes a longer time for the compressed air A to contact the outer peripheral surface of the inner ring spacer 5 than in the case where it flows straight in the axial direction, and the inner ring spacer 5 can be cooled more efficiently. it can. For this reason, the inner ring spacer 5 can be cooled more efficiently.

  As described above, the inner ring spacer 5 is efficiently cooled, so that the inner ring 3 and the main shaft 7 of the rolling bearing 1 can be effectively cooled via the inner ring spacer 5. In this cooling structure, the cooling efficiency is obtained only by providing a structural ingenuity in which the outer ring spacer 4 and the inner ring spacer 5 are each provided with an annular fixed recess 13 and a rotation recess 14 and the nozzle hole 15 is inclined. Therefore, it is not necessary to increase the output of the air supply device that supplies the compressed air A, and power consumption can be suppressed.

  In addition, when the fixed side recess 13 and the rotation side recess 14 are provided, the following effects are also obtained. That is, the compressed air A discharged into the space 20 between the outer ring spacer 4 and the inner ring spacer 5 is discharged to the outside of the bearing through the radial clearance δa between the outer ring spacer 4 and the inner ring spacer 5. . At that time, at least a part of the compressed air A flows into the bearing. Since the radial clearance δa is narrower than the space 20, the flow velocity of the compressed air A flowing through the radial clearance δa in each circumferential portion is made uniform, and the flow velocity of the compressed air A flowing into the bearing becomes uniform. . Thereby, the collision sound between the compressed air A and the rotating rolling element 9 can be reduced.

  In the bearing device J shown in FIG. 2, the rotation-side recess 14 provided in the inner ring spacer 5 has a rectangular cross section, but the shape of the rotation-side recess 14 is not limited to this. For example, as shown in FIG. 5, the corner portion 21 of the rotation-side dent portion 14 may be an inclined surface. Moreover, as shown in FIG. 6, the bottom face of the rotation side dent part 14 may have a circular arc shape in cross section.

  Further, as shown in FIG. 7, a groove-like recess 22 is formed on the bottom surface of the rotation-side recess 14 by knurling or the like, or a plurality of grooves are formed on the bottom surface of the rotation-side recess 14 as shown in FIG. The circumferential groove 23 may be provided, and the bottom surface area may be increased by making the bottom surface of the rotation-side indented portion 14 an uneven surface. As described above, by increasing the surface area of the bottom surface of the rotation-side recess 14, heat exchange between the inner ring spacer 5 and the compressed air A can be performed efficiently, and the cooling effect is further enhanced.

  In each of the above embodiments, the case where the rolling bearing 1 is used for inner ring rotation has been shown, but the present invention can also be applied when used for outer ring rotation. In this case, for example, a shaft (not shown) fitted to the inner circumference of the inner ring 3 is a fixed member, and a roller (not shown) fitted to the outer circumference of the outer ring 2 is a rotating member.

  As mentioned above, although the form for implementing this invention based on the Example was demonstrated, embodiment disclosed here is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 ... Rolling bearing 2 ... Outer ring (fixed side ring)
3. Inner ring (rotating raceway)
4. Outer ring spacer (fixed side spacer)
5 ... Inner ring spacer (rotating side spacer)
6 ... Housing (fixing member)
7 ... Spindle (Rotating member)
11 ... Outer ring spacer body (fixed side spacer body)
DESCRIPTION OF SYMBOLS 12 ... Lubricating oil hole formation member 31 ... Lubricating oil hole 13 ... Fixed side recessed part 14 ... Rotation side recessed part 15 ... Nozzle hole 15a ... Outlet 22 ... Groove-shaped recessed part 23 ... Circumferential groove A ... Compressed air J ... Bearing apparatus

Claims (6)

A stationary spacer and a rotating spacer are provided adjacent to the stationary bearing ring and the rotating bearing ring facing the inside and outside of the rolling bearing, respectively, and the stationary bearing ring and the stationary spacer are fixed members and In the bearing device installed in the fixed member of the rotating member, the rotating side race ring and the rotating side spacer are installed in the rotating member of the fixed member and the rotating member,
An axis that is provided with an annular fixed recess on the circumferential surface of the fixed spacer facing each other and that faces the fixed recess on the circumferential surface of the rotating spacer facing each other. An annular rotation-side recess is provided in the direction position, and a nozzle hole that discharges compressed air from an outlet that opens to the bottom surface of the fixed-side recess to the bottom surface of the rotation-side recess is formed on the rotation-side spacer. A cooling structure for a bearing device provided to be inclined forward in the rotational direction.   2. The cooling structure for a bearing device according to claim 1, wherein an axial length of the rotation-side recess is at least twice a diameter of the nozzle hole.   3. The cooling structure for a bearing device according to claim 1, wherein a radial depth of the rotation-side recess is within a range of 10% to 50% of a radial thickness of the rotation-side spacer. A cooling structure for a bearing device.   4. The cooling structure for a bearing device according to claim 1, wherein a cross-shaped or streak-like groove-shaped recess is formed on a bottom surface of the rotation-side recess. 5.   4. The cooling structure for a bearing device according to claim 1, wherein a plurality of circumferential grooves are provided on a bottom surface of the rotation-side recess portion. 5.   6. The cooling structure for a bearing device according to claim 1, wherein the fixed-side spacer includes a fixed-side spacer body in which the nozzle hole is formed, and lubricating oil is applied to the rolling bearing. A lubricating oil hole forming member in which a lubricating oil hole to be supplied is formed, a peripheral surface of the fixed side spacer main body is the bottom surface of the fixed side recessed portion, and a side surface of the lubricating oil hole forming member is The cooling structure of the bearing apparatus which is a side wall surface of the said fixed side dent part.

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