JP2008309177A - Bearing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing device with an inclined cage having improved ball guiding and holding functions. <P>SOLUTION: On the outer peripheral face of the cage 14, a cylindrical face 14e is formed which extends to a position where it and pocket portions 14d holding balls 13 overlapp when the cage 14 is viewed in a direction perpendicular to the axis. Thus, the amount of a raw material for the cage 4 is reduced to reduce cost, and the large-area cylindrical face 14e is supported by a chuck or the like to ensure holding during cutting work or the like, resulting in accurate machining. Besides, annular portions 14a, 14b extend across the PCD positions of the balls 13 held in the pockets 14d in the radial direction to surely guide and hold the balls 13. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a bearing device having balls as rolling elements.

  A so-called angular contact ball bearing is widely used in rotation support portions of various mechanical devices because one bearing can support both a radial load and an axial load. In an angular contact ball bearing, a ball as a rolling element is incorporated between an outer ring and an inner ring with a contact angle of about 15 ° to 40 °. Generally, a ball is rotatably held by a tilted cage having a plurality of pockets formed in a tapered cylindrical main body or a crown type cage having a plurality of pockets formed in an annular main portion. Thus, contact between the rolling surfaces of the balls is prevented, and an increase in rotational resistance or seizure based on contact friction is prevented.

Patent Document 1 discloses an inclined type retainer that is set by offsetting the center of a partially concave spherical surface of a pocket toward one end surface as an inclined type retainer used for an angular contact ball bearing.
Japanese Patent Publication No. 64-8208

  By the way, according to the technique of Patent Document 1, one annular portion of the inclined cage is disposed radially outward from the PCD of the ball held in the pocket portion. Therefore, there is a problem that the ball guiding / holding function is low.

  The present invention has been made in view of the problems of the prior art, and an object of the present invention is to provide a bearing device having an inclined retainer with an improved ball guiding / holding function.

A bearing device according to a first aspect of the present invention is a bearing device having an outer ring, an inner ring, a plurality of balls disposed between the outer ring and the inner ring, and a cage that holds the balls.
The retainer has a pair of annular portions and a plurality of column portions connecting the annular portions, and at least a part of the inner peripheral surface of the column portions and the outer peripheral surface is relative to the axis of the retainer. Leaning
The outer peripheral surface of the cage is formed with a cylindrical surface extending to a position overlapping with the pocket portion that holds the ball when the cage is viewed in the direction orthogonal to the axis, and the annular portion is The ball portion extends in the radial direction across the position of a PCD (Pitch Circle Diameter) of the ball held in the pocket portion.

A bearing device according to a second aspect of the present invention is the bearing device having an outer ring, an inner ring, a plurality of balls disposed between the outer ring and the inner ring, and a cage that holds the balls.
The cage includes a pair of annular portions and a plurality of column portions that connect the annular portions, and at least a part of the inner peripheral surface of the column portions and the outer peripheral surface is relative to the axis of the retainer. Leaning
On the inner peripheral surface of the cage, a cylindrical surface is formed that extends to a position where it overlaps with a pocket portion that holds the ball when the cage is viewed in the direction orthogonal to the axis, and the annular portion is The ball portion extends in the radial direction across the position of the PCD of the ball held in the pocket portion.

  According to 1st this invention, the cylindrical surface extended to the position which overlaps with the pocket part which hold | maintains the said ball, when the said holder | retainer is seen in an axial orthogonal direction is formed in the outer peripheral surface of the said holder | retainer. Therefore, the cost can be reduced by reducing the material amount of the cage, and the cylindrical surface having a large area can be supported by a chuck or the like, so that the retainer can be securely held during cutting. Highly accurate processing can be performed. Further, since the annular portion extends in the radial direction across the position of the PCD of the ball held in the pocket portion, the ball can be reliably guided and held.

  Since the outer periphery of the cylindrical surface is positioned radially outward from the position where the ball contacts the cage, it is possible to suppress a decrease in the ball guiding / holding function.

  In the case where the retainer is a rice bran retainer, the amount of material and the amount of processing can be suppressed, so the effect of the present invention is particularly high. The rice bran cage refers to a cage formed by cutting a metal material or the like.

  It is preferable that the cage is of a ball guide type because lubricity can be improved and the temperature of the bearing can be reduced. The ball guide type means that the cage is supported only by the balls without contacting the outer ring or the inner ring.

  According to the second aspect of the present invention, the inner peripheral surface of the cage has a cylindrical surface that extends to a position where it overlaps with the pocket portion that holds the ball when the cage is viewed in the direction orthogonal to the axis. Since it is formed, the cost is reduced by reducing the material amount of the cage, and the cylindrical surface having a large area is supported by a chuck or the like, so that the holding during cutting or the like is surely performed. Thus, it is possible to perform processing with high accuracy. Further, since the annular portion extends in the radial direction across the position of the PCD of the ball held in the pocket portion, the ball can be reliably guided and held.

  Since the inner peripheral surface of the cylindrical surface is located radially inward from the position where the ball contacts the cage, it is possible to suppress a decrease in the ball guiding / holding function.

  The cage is preferably a rice bran cage.

  It is preferable that the cage is of a ball guide type because lubricity can be improved and the temperature of the bearing can be reduced.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a centrifugal pump using the bearing device according to the present embodiment. In FIG. 1, a shaft 3 with an impeller 2 attached to one end is rotated with respect to a housing 1 by a deep groove ball bearing 4 and a pair of angular contact ball bearings 10, 10 which are aligned with the back surface and preloaded by a preload plate 5. It is supported freely. A motor (not shown) is connected to the other end of the shaft 3.

  When a motor (not shown) is driven, the impeller 2 rotates together with the shaft 3, and the fluid is pumped from the intake side passage 1a of the housing 1 to the discharge side passage 1c through the annular passage 1b. By supporting the shaft 3 using a pair of angular contact ball bearings 10 and 10 that are back-fitted and preloaded, a highly accurate positioning head of the impeller 2 can be realized, and the efficiency of the pump can be improved. In addition, the bearing size tolerance and rotational accuracy of the angular contact ball bearing 10 can contribute to low noise and low vibration of the pump if it conforms to the JIS P6 standard. For example, when the shaft 3 is stretched due to a temperature rise, the pair of angular contact ball bearings 10 and 10 side prevents the shaft 3 from being displaced with respect to the housing 1, but the deep groove ball bearing 4 side has the housing 1. The displacement of the shaft 3 with respect to is allowed. Angular contact ball bearings 10 and 10 may be provided on the impeller 2 side.

  FIG. 2 is a cross-sectional view of the angular contact ball bearing 10. FIG. 3 is an enlarged sectional view showing the cage of the angular contact ball bearing 10. In FIG. 2, the angular contact ball bearing 10 includes an outer ring 11, an inner ring 12, a plurality of balls 13 disposed between the outer ring 11 and the inner ring 12, and a cage 14 that holds the balls 13. The cage 14 is a ball guide type.

  In FIG. 3, the cage 14 is a rice brace machine that is machined from a material having a cylindrical cross section made of a copper alloy or the like, and includes a pair of annular portions 14 a and 14 b and an annular portion 14 a and 14 b. A plurality of column portions 14c to be connected are integrally formed. The column part 14c is inclined so as to approach the axis of the retainer 14 as it goes from the annular part 14a to the annular part 14b. The annular portions 14a and 14b extend in the radial direction across the position of the PCD of the ball 13 held in the pocket portion 14d.

  When the cage 14 is viewed in the direction orthogonal to the axis, the outer circumferential surface of the cage 14 is inclined with respect to the cylindrical surface 14e extending from the end portion on the annular portion 14a side to the position overlapping the pocket portion 14d and the axis. 14f. The cylindrical surface 14e has an axial length suitable for holding with a chuck or the like when the retainer 14 is cut.

  In the cross section shown in FIG. 3, the inner surface shape of the annular portion 14a is recessed so that the ball 13 indicated by the alternate long and short dash line contacts the annular portion 14a at two points P1 and P2, and further, with respect to the annular portion 14b. Thus, the inner surface shape of the annular portion 14b is recessed so as to contact at two points P3 and P4. It is preferable that the line connecting P1 and P3 passes through the center of the ball 13. Here, since the outer periphery of the cylindrical surface 14e is located radially outward from the position P1 at which the ball 13 contacts the annular portion 14a of the retainer 14, the lowering of the guiding / holding function of the ball 13 can be suppressed.

  Since the outer peripheral surface of the cage 14 is formed with a cylindrical surface 14e that extends to a position where it overlaps with the pocket portion 14d that holds the ball 13 when the cage 14 is viewed in the direction orthogonal to the axis, By reducing the amount of material and processing by reducing the inner and outer diameters of the 14 cylindrical materials, the cost can be reduced even when relatively expensive copper alloys are used, and the cylindrical surface has a large area. By supporting 14e with a chuck or the like, it is possible to perform machining with high accuracy by reliably holding during cutting or the like. Furthermore, since the annular portions 14a and 14b extend in the radial direction across the position of the PCD of the ball 13 held in the pocket portion 14d, the ball 13 can be reliably guided and held.

  FIG. 4 is a cross-sectional view of an angular contact ball bearing 10 'according to another embodiment. FIG. 5 is an enlarged sectional view showing the cage of the angular contact ball bearing 10 ′.

  In the present embodiment, in FIG. 5, the inner peripheral surface of the cage 14 ′ extends from the end on the annular portion 14 b side to a position where it overlaps with the pocket portion 14 d when the cage 14 is viewed in the direction orthogonal to the axis. An existing cylindrical surface 14e 'and a tapered surface 14f' inclined with respect to the axis. The cylindrical surface 14e 'has a length in the axial direction suitable for being held by a chuck or the like when the retainer 14 is cut.

  In the cross section shown in FIG. 5, the inner surface shape of the annular portion 14a is recessed so that the ball 13 indicated by the alternate long and short dash line is in contact with the annular portion 14a at two points P1 and P2, and further to the annular portion 14b. Thus, the inner surface shape of the annular portion 14b is recessed so as to contact at two points P3 and P4. Here, since the inner periphery of the cylindrical surface 14 e ′ is located radially inward from the position P <b> 4 where the ball 13 contacts the annular portion 14 b of the cage 14, it is possible to suppress a decrease in the guide / holding function of the ball 13. Since other configurations are the same as those in the above-described embodiment, the description thereof is omitted.

  FIG. 6 is a cross-sectional view of an angular contact ball bearing 10 ″ according to another embodiment. FIG. 7 is an enlarged cross-sectional view of a cage of the angular contact ball bearing 10 ″.

  In the present embodiment, in FIG. 7, the outer peripheral surface of the cage 14 ″ extends from the end portion on the annular portion 14a side to the position where it overlaps with the pocket portion 14d when the cage 14 ″ is viewed in the direction orthogonal to the axis. It consists of an existing cylindrical surface 14e and a tapered surface 14f inclined with respect to the axis. The cylindrical surface 14e has an axial length suitable for holding with a chuck or the like when the retainer 14 is cut. Further, the inner peripheral surface of the cage 14 ″ has a cylindrical surface 14e ′ extending from the end portion on the annular portion 14b side to a position overlapping with the pocket portion 14d when the cage 14 is viewed in the direction orthogonal to the axis, The cylindrical surface 14e ′ has a length in the axial direction suitable for holding with a chuck or the like when the retainer 14 is cut.

  In the cross section shown in FIG. 7, the inner surface shape of the annular portion 14 a is recessed so that the ball 13 indicated by the alternate long and short dash line contacts the annular portion 14 a at two points P <b> 1 and P <b> 2. Thus, the inner surface shape of the annular portion 14b is recessed so as to contact at two points P3 and P4. Here, the outer periphery of the cylindrical surface 14e is positioned radially outward from the position P1 where the ball 13 contacts the annular portion 14a of the retainer 14, and the inner periphery of the cylindrical surface 14e ' Since it is located on the radially inner side from the position P4 that contacts the annular portion 14b, it is possible to suppress a decrease in the guide / holding function of the ball 13. Since other configurations are the same as those in the above-described embodiment, the description thereof is omitted.

  The present invention has been described above with reference to the embodiments. However, the present invention should not be construed as being limited to the above-described embodiments, and can be modified or improved as appropriate. For example, the angular contact ball bearing 10 can be used in a front combination as shown in FIG. 8 or in a front / rear combination as shown in FIG. 9, and as shown in FIGS. A contact ball bearing may be combined. At this time, the tolerance of the axial gap is set to ± 1 to ± 20 μm, thereby realizing high-precision positioning of the pump impeller. Also, by combining universal bearings with the same identification number in such a way that a predetermined clearance and preload can be obtained, a universal combination bearing with the same front / back differential width and controlled to a predetermined value can be used regularly. Or the replacement cost at the time of damage, the stock quantity of the bearing for replacement, etc. can be held down.

It is sectional drawing of the centrifugal pump using the bearing apparatus concerning this Embodiment. 1 is a cross-sectional view of an angular contact ball bearing 10. FIG. 2 is an enlarged cross-sectional view showing a cage of the angular contact ball bearing 10. FIG. It is sectional drawing of the angular contact ball bearing 10 '. It is sectional drawing which expands and shows the holder | retainer of the angular contact ball bearing 10 '. It is sectional drawing of the angular contact ball bearing 10 ". It is sectional drawing which expands and shows the retainer of the angular contact ball bearing 10 ''. It is sectional drawing of the angular contact ball bearing 10 made face-to-face. It is sectional drawing of the angular contact ball bearing 10 made into front and back alignment. It is sectional drawing of the angular contact ball bearing 10 which combined three. It is sectional drawing of the angular contact ball bearing 10 which combined three. It is sectional drawing of the angular contact ball bearing 10 which combined three.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Housing 1a Intake side passage 1b Annular passage 1c Discharge side passage 2 Impeller 3 Shaft 4 Deep groove ball bearing 5 Preload plate 10, 10 ', 10 "Angular contact ball bearing 11 Outer ring 12 Inner ring 13 Ball 14, 14', 14" Holding 14a Annular part 14b Annular part 14c Column part 14d Pocket part 14e Cylindrical surface 14f Tapered surface

Claims (8)

In a bearing device having an outer ring, an inner ring, a plurality of balls disposed between the outer ring and the inner ring, and a cage that holds the ball,
The cage includes a pair of annular portions and a plurality of column portions that connect the annular portions, and at least a part of the inner peripheral surface of the column portions and the outer peripheral surface is relative to the axis of the retainer. Leaning
The outer peripheral surface of the cage is formed with a cylindrical surface extending to a position overlapping with the pocket portion that holds the ball when the cage is viewed in the direction orthogonal to the axis, and the annular portion is A bearing device that extends in a radial direction across the position of the PCD of the ball held in the pocket portion.   2. The bearing device according to claim 1, wherein an outer periphery of the cylindrical surface is located radially outward from a position where the ball contacts the cage.   The bearing device according to claim 1, wherein the cage is a rice bran cage.   The bearing device according to claim 1, wherein the cage is a ball guide type. In a bearing device having an outer ring, an inner ring, a plurality of balls disposed between the outer ring and the inner ring, and a cage that holds the ball,
The cage includes a pair of annular portions and a plurality of column portions that connect the annular portions, and at least a part of the inner peripheral surface of the column portions and the outer peripheral surface is relative to the axis of the retainer. Leaning
On the inner peripheral surface of the cage, a cylindrical surface is formed that extends to a position where it overlaps with a pocket portion that holds the ball when the cage is viewed in the direction orthogonal to the axis, and the annular portion is The bearing device extends in the radial direction across the position of the PCD of the ball held in the pocket portion.   The bearing device according to claim 5, wherein an inner peripheral surface of the cylindrical surface is located radially inward from a position where the ball contacts the cage.   The bearing device according to claim 5 or 6, wherein the cage is a rice bran cage.   The bearing device according to claim 5, wherein the cage is a ball guide type.

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