JP3207410U - Rolling bearing - Google Patents

Abstract

Provided is a rolling bearing capable of suppressing unevenness in the circumferential direction of rolling elements and suppressing the whirling of a rotating shaft to be small. A rolling bearing includes an inner ring having an inner ring raceway surface on an outer peripheral surface, an outer ring having an outer ring raceway surface on an inner peripheral surface, and a plurality of rolling bearings provided between the inner ring raceway surface and the outer ring raceway surface. And a retainer 15 made of a synthetic resin that holds a plurality of rolling elements 13 at substantially equal intervals in the circumferential direction. The width dimension of the cut part is ΔC, the width dimension of one pillar part in the cut part is S1, the width dimension of the other pillar part is S2, and the width dimension of the uncut pillar part of the cage is S3. In this case, the relationship of S3 = S1 + S2 + ΔC is satisfied. [Selection] Figure 5

Description

  The present invention includes, for example, industrial machinery, robot joints and turning mechanisms, machine tool spindles, rotary tables and spindle turning mechanisms, medical equipment, semiconductor / liquid crystal manufacturing devices, optical and optoelectronic devices, and the like. The present invention relates to a rolling bearing used in the above.

  As a conventional rolling bearing, as shown in FIG. 6, a synthetic resin crown-shaped cage having a cut portion (ΔL) at one place in the circumferential direction has been proposed (for example, see Patent Documents 1 and 2). ). In the rolling bearing described in Patent Document 1, by providing a cutting portion, the tension force generated between the ball and the pocket due to the difference in thermal expansion coefficient between the inner and outer rings and the ball and the cage is alleviated. It is described that the wear and the like are prevented.

  Further, in the rolling bearing described in Patent Document 2, a cutting part is provided at one place in the circumferential direction, and the circumferential width of the cutting part is set as an extension of the cage due to a change in temperature and a change in water absorption rate. It is described to secure a guide clearance.

JP 2003-336640 A JP 2006-226696 A

  By the way, in the rolling bearing described in Patent Document 1, the ball guide method is adopted, and the radial clearance between the ball and the pocket is set to be small. (For example, when the inner ring, outer ring and ball are made of bearing steel, and the cage is made of synthetic resin such as polyamide resin) It is difficult to expand, and the relative expansion is directed in the circumferential direction.

  As a result, the clearance in the circumferential direction of the cutting part of the cage is reduced, and if the temperature rise value of the bearing is high, including the operating environment temperature, the circumferential end surfaces of the cutting part of the cage are stretched and interfered, There is a problem that heat generation, wear, and damage occur in the interference portion. In addition, when the cage is formed of a general general-purpose synthetic resin such as a polyamide resin, the cage may expand by absorbing moisture in the air, and the amount of expansion due to water absorption is also a problem. Further, as shown in FIG. 6, the circumferential distance between the balls becomes (ΔL + 2 · ΔS) at the cut portion, which is larger than the distance between the other balls (ΔS: column portion circumferential width dimension). As a result, uneven distribution in the circumferential direction of the balls occurs.

  Further, in the rolling bearing described in Patent Document 2, the circumferential width of the cut portion is defined as the extension of the cage (temperature expansion + water absorption expansion) due to temperature change and water absorption change. However, under conditions where the temperature rise is small or the atmosphere is dry, the change in the circumferential width of the cut part is small, and the circumferential distance between the balls at the part across the cut part is It becomes larger than the circumferential distance between the balls, and uneven distribution in the circumferential direction of the balls occurs.

  If the balls are not evenly distributed in the circumferential direction, the radial rigidity of the bearing will be non-uniform in the circumferential phase (decrease in rigidity due to the phase of the unevenly distributed portion of the ball in the circumferential direction). A swing corresponding to the revolution period of the ball, a so-called NRRO value (a cycle of about once per two rotations of the inner ring) increases. In particular, when this bearing is used in a rotation support part such as a spindle of a machine tool, a rotary table, and a turning mechanism part of the spindle that require rotational accuracy, the rotation of the rotary shaft becomes large (NRRO value is large), and milling There is a problem that a striped pattern is generated on the processed surface in machining, and a stitching defect on the processed surface or a deterioration in roundness occurs in lathe processing.

  The present invention has been made in order to eliminate such inconveniences, and the purpose of the present invention is to reduce rolling around the rotating shaft by suppressing the uneven distribution of the rolling elements in the circumferential direction. It is to provide a bearing.

In order to achieve the above object, a rolling bearing according to claim 1 includes an inner ring having an inner ring raceway surface on an outer peripheral surface, an outer ring having an outer ring raceway surface on an inner peripheral surface, the inner ring raceway surface, and the outer ring raceway surface. And a plurality of rolling elements provided so as to be freely rollable between them, and a cut portion formed in at least one place in the circumferential direction, and holding the plurality of rolling elements at equal intervals in the circumferential direction A rolling bearing provided with
The circumferential width dimension of the cut part is ΔC, the circumferential width dimension of one column part in the cut part is S ₁ , and the circumferential width dimension of the other column part in the cut part is S ₂ , If the circumferential width of the column portion which is not cut in the cage was S _3, satisfy the relationship of _{S 3 = S 1 + S 2} + ΔC, and the [Delta] C is characterized by greater than zero.

  According to the rolling bearing of the present invention, it is possible to suppress the uneven distribution in the circumferential direction of the rolling elements, to suppress the whirling of the rotating shaft, and to obtain stable rotational performance.

It is principal part sectional drawing for demonstrating the rolling bearing which concerns on 1st Embodiment of this invention. FIG. 2 is a cross-sectional view of a crown-shaped cage incorporated in the rolling bearing shown in FIG. 1. FIG. 2 is a partial perspective view of a crown-shaped cage incorporated in the rolling bearing shown in FIG. 1. It is the figure which fractured | ruptured the part seen from the arrow B direction of FIG. It is principal part sectional drawing for demonstrating the structure of the crown-shaped holder | retainer integrated in the rolling bearing shown in FIG. 1, and a rolling element. It is principal part sectional drawing which looked at the conventional cage | basket from the axial direction. It is explanatory drawing for demonstrating the deformation amount of the radial direction of an inner ring | wheel. It is explanatory drawing for demonstrating the calculation method of the cross-sectional secondary moment of an inner ring | wheel. It is a graph which shows the relationship between a cross-sectional dimension ratio (B / H) and the deformation amount of the inner / outer ring in the radial direction. It is a graph which shows the relationship between a cross-sectional dimension ratio (B / H) and the cross-sectional secondary moment I of an inner-outer ring. It is a graph which shows the relationship between a cross-sectional dimension ratio (B / H) and the deformation amount of the inner and outer ring | wheels of a radial direction. It is a graph which shows the relationship between a cross-sectional dimension ratio (B / H) and the cross-sectional secondary moment I of an inner-outer ring. It is principal part sectional drawing for demonstrating the rolling bearing which concerns on 2nd Embodiment of this invention. It is principal part sectional drawing for demonstrating the rolling bearing which concerns on 3rd Embodiment of this invention. It is principal part sectional drawing for demonstrating the rolling bearing which concerns on 4th Embodiment of this invention. It is principal part sectional drawing for demonstrating the rolling bearing which concerns on 5th Embodiment of this invention. It is principal part sectional drawing for demonstrating the rolling bearing which concerns on 6th Embodiment of this invention. It is principal part sectional drawing for demonstrating the rolling bearing which concerns on 7th Embodiment of this invention. It is principal part sectional drawing for demonstrating the rolling bearing which concerns on 8th Embodiment of this invention. It is principal part sectional drawing for demonstrating the rolling bearing which concerns on 9th Embodiment of this invention. It is principal part sectional drawing for demonstrating the rolling bearing which concerns on 10th Embodiment of this invention. It is principal part sectional drawing for demonstrating the rolling bearing which concerns on 11th Embodiment of this invention. It is principal part sectional drawing for demonstrating the rolling bearing which concerns on 12th Embodiment of this invention.

Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
FIG. 1 is a cross-sectional view of an essential part showing a state in which two single-row ball bearings according to the first embodiment of the present invention are combined, FIG. 2 is a cross-sectional view showing a ball guide cage, and FIG. FIG. 4 is a partial perspective view seen from the direction of arrow B, FIG. 4 is an arrow view seen from the direction of arrow B in FIG. 2, and FIG. 5 is a diagram for explaining the configuration of the crown-shaped cage and rolling elements incorporated in the rolling bearing shown in FIG. It is principal part sectional drawing.

  As shown in FIG. 1, a rolling bearing 10 (hereinafter also referred to as a narrow ball bearing 10) of this embodiment is an angular ball bearing, and two rows of angular ball bearings are combined in the back (contact angle is C). Array). Each rolling bearing 10 is freely rollable between an inner ring 11 having an inner ring raceway surface 11a on an outer peripheral surface, an outer ring 12 having an outer ring raceway surface 12a on an inner peripheral surface, and an inner ring raceway surface 11a and an outer ring raceway surface 12a. A plurality of balls (rolling elements) 13 provided, and a cutting portion 14 (see FIG. 5) is formed at one place in the circumferential direction, and the plurality of balls 13 is made of a synthetic resin that holds the balls 13 in the circumferential direction at substantially equal intervals. The crown-shaped cage 15 is provided. Further, non-contact type seal members 16 are mounted on the inner peripheral surfaces of the outer ends of the outer rings 12 of the two rows of narrow ball bearings 10 in the axial direction. The seal member 16 may be a contact type, and the material and shape are not particularly limited.

  In this embodiment, in order to save space in the axial direction, the axial sectional width B and the radial sectional height H of the rolling bearing 10 (= (outer ring outer diameter D−inner ring inner diameter d) / 2) and The cross-sectional dimension ratio (B / H) is set to B / H <0.63.

  B / H is theoretically B / H> 0, but in reality, considering the design, selection, etc. of the ball diameter, cage, and seal member to be used, B / H> 0. 10, preferably B / H> 0.20, more preferably B / H> 0.30.

  Further, in the case of standard size ball bearings defined by the International Organization for Standardization (ISO), those with a B / H of around 1.0 account for the majority. Therefore, if B / H <0.5 is set, the narrow ball bearings 10 for two rows can be disposed in the width direction space for about one row of standard ball bearings, and space saving can be achieved.

  In the case of angular contact ball bearings, only one axial load can be received in one row and moment load cannot be received. However, by combining two or more rows, the axial load and moment load in both directions can be reduced. Load becomes possible. In addition, since preload can be applied, it is possible to save space and increase radial rigidity, axial rigidity, moment rigidity, and the like.

  Moreover, if B / H <0.25, it is possible to arrange four rows of narrow ball bearings in a space in the width direction of about one row of standard ball bearings with further space saving, and further increase rigidity. Improvement is possible.

Here, FIG. 9 and FIG. 10 show the standard thin ball bearings (bearing inner diameter: φ38.1 mm, bearing outer diameter: φ47.625 mm, bearing width: 4.762 mm, cross-sectional dimension ratio ( B / H) = 1) as a reference, the radius of the inner and outer ring rings when the bearing inner diameter is changed without changing the bearing outer diameter and bearing width, that is, when the value of (B / H) is changed. direction of deformation characteristics (see FIG. 7: illustrates the inner ring) and radial cross-sectional secondary moment I: shows the calculation result of comparison (see FIG. 8 calculated as I = bh ^3/12).

  FIGS. 11 and 12 show the standard thin ball bearings (bearing inner diameter: φ63.5 mm, bearing outer diameter: φ76.2 mm, bearing width: 6.35 mm, cross-sectional dimension ratio = 1). ) And the radial deformation characteristics and radius of the inner and outer ring rings when the bearing inner diameter is changed without changing the bearing outer diameter and bearing width, that is, when the value of (B / H) is changed. The calculation result which compared the cross-sectional secondary moment I of the direction is shown.

  In any of the bearings, (B / H) = 0.63 or less, and the change in the rigidity increase rate gradient is noticeable. That is, when (B / H) = 0.63, the increase in the secondary moment I of the cross section becomes significant, and the decrease in the deformation amount of the inner and outer ring in the radial direction becomes saturated. This can prevent bearing deformation due to lathe processing and grinding processing forces when manufacturing inner and outer rings, which is a problem with conventional ultra-thin ball bearings, and improves bearing accuracy such as roundness and uneven thickness. be able to.

  Also, by setting (B / H) to less than 0.63, when the bearing is incorporated in the shaft or housing (especially when it is assembled by clearance fitting with the shaft or housing), the outer ring is pressed against the end face, and the inner ring is the bearing. It is possible to suppress deformation of the inner and outer rings (especially worsening of roundness) when they are fixed with nuts, etc., as well as torque failure and rotation accuracy caused by deformation, or problems such as increased heat generation, wear and seizure. Can be prevented.

  Furthermore, by setting (B / H) to less than 0.63, the width of the bearing is about half that of a conventional standard single-row ball bearing, so the ball diameter is also about half that of a conventional ball bearing. Conversely, the number of balls per row increases at least twice, and the bearing stiffness increases compared to conventional ball bearings.

  The dimension series defined by the International Organization for Standardization (ISO) is 18 (for example, 6820), 19 (for example, 6938), 10 (for example, 7016A), 02 (for example, 7224C), 03 (for example, 7350A). In the case of standard size ball bearings such as the above, when the inner diameter of the bearing is φ5 mm to φ500 mm, the cross-sectional dimension ratio (B / H) is B / H = 0.63 to 1.17. Since the ball bearing 10 is narrow in the axial direction, it does not correspond to the above-described cross-sectional dimension ratio.

  In the narrow ball bearing 10 of this embodiment, in order to increase the load capacity and rigidity of the bearing, the pitch between the balls 13 adjacent in the circumferential direction is made as small as possible, and the number of balls is increased as much as possible. In a normal ball bearing, the number of balls is at most about 30 to 40 or less per row, but in this embodiment, 50 or more, preferably 60 or more, more preferably 70 or more per row. .

  In the case of an angular contact ball bearing, the contact angle is approximately 60 ° or less, preferably 50 ° or less in order to suppress the ball and the inner / outer ring groove contact portion from riding on the shoulder portion of the inner / outer ring groove when a large moment load is applied. More preferably, it is 40 ° or less, but if it is less than 20 °, the allowable axial load and moment rigidity are lowered, which is not preferable. The appropriate ball diameter in the present embodiment varies depending on whether or not a seal member or the like is mounted. However, in order to increase rigidity, if the ball diameter is extremely reduced, the surface pressure between the contact portions between the balls and the track grooves of the inner and outer rings is reduced. In general, the pressure resistance is likely to be reduced, so that generally 30 to 90% of the bearing width (B) is desirable.

  Furthermore, in this embodiment, the axial pitch of the balls 13 is shifted as much as possible to the opposite side of the end face on the combination side (FIG. 1: X1> X2), and the ring portion 17 (see FIGS. 2 to 5) of the cage 15 is used for the bearing combination. It is arranged so as to be on the end face side, so that the axial thickness of the ring portion 17 is increased, and the distance between the operating points for increasing the moment rigidity can be increased.

  Also, the bearing material is not particularly limited, such as standard bearing steel (SUJ2 or SUJ3), but if necessary, these materials can provide mechanical properties such as dimensional stability and wear resistance of the bearing. In order to improve, at least one of the inner ring 11 and the outer ring 12 may be subjected to sub-zero treatment.

  As a sub-zero treatment method, for example, immediately after quenching, an atmosphere of about −150 ° C. is formed using liquid nitrogen, and tempering is performed after the sub-zero treatment. Then, the sub-zero process and the tempering process are repeated several times. In the sub-zero treatment using liquid nitrogen as the cooling solvent, the number of repetitions may be at most about 3. Residual austenite (γR) in the structure is transformed into martensite by the sub-zero treatment. At the same time, the stabilization of crystal grains is also promoted, thereby improving mechanical properties such as prevention of dimensional change with time and wear resistance.

  In the case of the present embodiment, since the axial widths of the inner ring 11 and the outer ring 12 are narrow, there is a tendency that dimensional changes such as warpage and roundness failure tend to occur. Accordingly, the sub-zero treatment can suppress the dimensional change with time, and in particular, in rotation support parts such as a rotary table of a machine tool, a spindle turning mechanism part, and a rotary mechanism part such as a drum of a printing machine that require bearing accuracy. When the narrow ball bearing 10 of the present embodiment is used, it is possible to prevent malfunctions of the equipment due to deterioration of the bearing accuracy, and it is possible to maintain a good function in the long term.

For example, in vacuum applications and corrosive environments, in addition to bearing steel, stainless steel materials that are corrosion resistant materials (for example, martensitic stainless steel materials such as SUS440C, austenitic stainless steel materials such as SUS304, precipitation of SUS630, etc.) Hardened stainless steel material), titanium alloy or ceramic material (eg, Si ₃ N ₄ , SiC, Al ₂ O ₃ , ZrO _2, etc.) may be employed.

The lubrication method is not particularly limited, and mineral oil grease or synthetic oil grease (for example, lithium or urea) or oil can be used in a general usage environment. Oil, or a solid lubricant such as fluororesin or MOS ₂ can be used.

  The cage 15 is a ball guide system, and as shown in FIGS. 2 to 4, the ring portion 17 and one end portion of the ring portion 17 are protruded in the axial direction at a plurality of positions at substantially equal intervals in the circumferential direction. Formed between the pillars 18, a large number of pockets 19 formed between the pillars 18 to hold the balls 13 so as to be able to roll in the circumferential direction, and the tip of the pockets 19 opposite to the ring parts 17. It has the structure of a flexible crown-shaped cage provided with a pair of ball locking portions that prevent the balls 13 from coming out. As in this embodiment, if the entrance portion of the pocket portion 19 is slightly smaller than the ball diameter and is provided with a catch (pachin allowance), the ball 13 can be assembled without being dropped when the inner ring 11 and the outer ring 12 are assembled. Easy. In addition, the shape of a holder | retainer is not limited to this embodiment, It can select suitably.

Further, as shown in FIG. 5, the cage 15 preliminarily cuts between the pocket portions 19 adjacent to each other at least at one place in the circumferential direction of the ring portion 17 to form a cut portion 14. The direction width dimension is ΔC, the circumferential width dimension of _one pillar part in the cut part is S ₁ , the circumferential width dimension of the other pillar part in the cut part is S ₂ , and the uncut pillar part of the cage S ₃ = S ₁ + S ₂ + ΔC where S ₃ is the circumferential width dimension of S ₃
It is comprised so that it may become a relationship.

  In the narrow ball bearing 10 as in the present embodiment, the cutting portion 14 is formed in the circumferential direction of the crown-shaped cage 15, and further, the following dimensional relationship is adopted, and the following effects are obtained.

  That is, in the case of the conventional cage, as shown in FIG. 6, the distance between the balls 13 in the cutting portion 14 is (ΔL + 2 · ΔS), and the distance between the other balls 13 (ΔS: the circumferential width of the column portion) Dimension), resulting in uneven distribution of the balls in the circumferential direction. If the balls are not evenly distributed in the circumferential direction, the radial rigidity of the bearing will be non-uniform in the circumferential phase (decrease in rigidity due to the phase of the unevenly distributed portion of the ball in the circumferential direction). A swing corresponding to the revolution period of the ball, a so-called NRRO value (a cycle of about once per two rotations of the inner ring) increases.

  In addition, the circumferential width dimension of the column portion 18 sandwiching the cut portion 14 and the width direction dimension of the uncut column portion 18 are the same, and the minimum portion of the circumferential width dimension of each column portion is the same. It is also conceivable to determine the thickness so as to secure a dimension that can withstand the load applied to the column portion 18. If it does so, the circumferential direction pitch of the ball | bowl of the cutting part 14 will become larger than the circumferential direction pitch of another ball | bowl, and the uneven distribution of the circumferential direction of a ball | bowl will arise. As a result, the radial rigidity of the bearing becomes non-uniform in the circumferential phase (stiffness decreases due to the phase of the unevenly distributed portion in the circumferential direction of the ball), so that the runout corresponding to the revolution period of the ball during rotation of the bearing, A so-called NRRO value (a cycle of about once per two rotations of the inner ring) increases.

On the other hand, in the present embodiment, as shown in FIG. 5, the circumferential width dimension of the cutting portion 14 is ΔC, the circumferential width dimension of one pillar portion in the cutting portion 14 is S ₁ , and the other width in the cutting portion 14. S ₃ = S ₁ + S regardless of the radial position of the cut portion 14, where S ₂ is the circumferential width dimension of the pillar portion and S ₃ is the circumferential width dimension of the pillar portion where the cage is not cut. ₂ + ΔC
It is configured to satisfy the relationship. That is, in this embodiment, since the distance between the balls 13 is configured to be equal to the distance between the other balls in the cutting portion 14 as well, the revolution period of the balls generated by the uneven distribution of the balls 13 as described above ( It is possible to greatly suppress an increase in rotational runout (NRRO) for each rotation cycle of the cage.

S ₁ and S ₂ in the above formula may be the same or different as long as S ₃ = S ₁ + S ₂ + ΔC is satisfied.

Moreover, it is preferable to set ΔC as follows.
The circumferential width dimension ΔC of the cut portion 14 is expected to be a decrease in the circumferential clearance due to the relative expansion of the cage due to the temperature rise of the bearing and the water absorption expansion under a predetermined condition, and the circumferential clearance does not become zero after the decrease. It is a clearance. As described above, it is possible to obtain a stable rotation performance of the bearing with less heat generation and less torque fluctuation without causing problems such as a damage of a tension between the cage and the ball during the rotation.

  Moreover, in the narrow ball bearing 10 like this embodiment, the following effects are produced by forming the cutting part 14 in the circumferential direction of the crown-shaped cage 15.

  That is, in a conventional narrow ball bearing having an annular crown-shaped cage without a cut portion, the ball diameter is limited by the dimension in the width direction and becomes small because the bearing is narrow. Therefore, the cross-sectional thickness of the annular portion of the cage is reduced, and the rigidity of the annular portion is small. Further, the deformation due to the measurement pressure at the time of measuring the dimension is large, the measurement of the radial dimension cannot be performed, and it cannot be determined whether or not the cage has an appropriate accuracy. If the pitch circle diameter at the center of the pocket diameter is deviated from the ball pitch circle diameter, the ball and the pocket portion interfere in the diameter direction because of the ball guide method.

  Even if the dimensional accuracy of the cage is appropriate, since the ball diameter is small, the cross-sectional thickness of the annular portion of the cage is thin, and the rigidity of the annular portion is small. The shape accuracy deteriorates. In addition, due to temperature rise and water absorption, the cage stretches in the diameter direction, causing tension between the ball and the pocket, causing problems such as wear on the pocket surface, large heat generation during rotation, uneven torque, and large torque. To do.

  In addition, in the case of a machined type cage having a ring on both sides without a cutting part, it has an annular shape on both sides and is relatively strong. In the case of an outer ring guide system for a synthetic resin cage, there is a possibility that the guide clearance will disappear due to temperature rise or expansion due to water absorption, and it may be devastated. On the other hand, in the case of the inner ring guide system, on the contrary, the guide clearance becomes too large, and noise or the like is generated due to abnormal vibration of the cage.

  On the other hand, in the narrow ball bearing 10 of the present embodiment, the rigidity is further reduced by forming the cut portion 14, but conversely, even if the pitch circle diameter is shifted, the elastic deformation is easy, and the ball Since it adapts to the pitch circle diameter, interference with a strong contact pressure between the ball 13 and the pocket portion 19 hardly occurs.

In addition, as a cage material, compared to standard resin materials (polyamide, polyacetal, polyphenylene sulfide, etc., whose linear expansion coefficient is 6 to 7 times that of bearing steel), the addition of reinforcing materials such as carbon fiber makes the wire Use a material whose expansion coefficient is close to the material of the inner and outer rings and rolling elements (for example, the linear expansion coefficient is about 0.5 to 2 times that of the inner and outer rings and rolling element material), or has little absorption expansion (many In both cases, the change in ΔC can be reduced by using a resin material, and the rotational accuracy can be further improved by using a resin material. In addition, it is possible to reduce ΔC necessary in advance to prevent interference of the circumferential cut portion 14, and accordingly, the circumferential width dimensions S ₁ and S ₂ of the column portion in the cut portion 14. It is also possible to increase the thickness. Conversely, if the circumferential width dimensions S ₁ and S ₂ of the pillar portion in the cut portion 14 are not increased and the thickness is not increased, the value of S ₃ of S ₃ = S ₁ + S ₂ + ΔC can be reduced. The number can be increased, and the load capacity and rigidity of the bearing can be increased.

  In addition, the cage shape is not a single-sided ring (ring) structure, but a cutting part is provided in a machined synthetic resin cage with a ring on both sides of the pocket, and a ball is inserted between the cutting parts as well. The structure may be sufficient. The circumferential width dimension ΔC after the ball is inserted may be an amount corresponding to the circumferential expansion due to a predetermined temperature rise and the water absorption expansion. By doing so, in the case of the outer ring guide system, it is possible to minimize the decrease in the guide clearance and prevent the biting trouble on the guide surface.

(Second Embodiment)
The rolling bearing according to the second embodiment of the present invention shown in FIG. 13 has a configuration in which the seal member 16 is omitted from the two rows of narrow ball bearings combined in the back surface of the first embodiment. In this embodiment, since the seal member 16 is not provided, the ball diameter can be increased. Moreover, when the ball | bowl of the same diameter of 1st Embodiment is used, since the sealing member 16 is not provided, the axial direction width | variety of a bearing can be made thinner.
Other configurations and operations are the same as those of the first embodiment.

(Third embodiment)
The rolling bearing according to the third embodiment of the present invention shown in FIG. 14 has a ball pitch circle diameter of (ball pitch circle diameter)> (D + d) / 2 with respect to that of the second embodiment. In this embodiment, compared with the ball pitch circle diameter = (D + d) / 2, it is possible to increase the number of balls per row of bearings, increase the load capacity of the bearings, and further improve the rigidity. .
Other configurations and operations are the same as those of the first embodiment.

(Fourth embodiment)
The rolling bearing according to the fourth embodiment of the present invention shown in FIG. 15 differs from that of the second embodiment in the ball diameter and ball pitch circle diameter of the left and right narrow ball bearings 10. In this embodiment, when the axial load is uneven between the left and right bearings, a bearing having a large ball diameter is provided on the side where the large load is applied, thereby preventing damage to the bearing and improving the life.
Other configurations and operations are the same as those of the first embodiment.

(Fifth embodiment)
The rolling bearing according to the fifth embodiment of the present invention shown in FIG. 16 has a configuration in which no seal groove is formed on the outer peripheral surface of the inner ring 11 opposed to the seal member 16 with respect to that of the first embodiment. Thereby, the shape of the inner ring 11 can be simplified.
Other configurations and operations are the same as those of the first embodiment.

(Sixth embodiment)
In the rolling bearing according to the sixth embodiment of the present invention shown in FIG. 17, the non-contact type seal members 16 are respectively mounted on the inner peripheral portions of both ends in the axial direction of the outer ring 12 of the narrow ball bearing 10. In this embodiment, it is possible to prevent the grease from flowing out of the bearing, and it is difficult for foreign matters to enter the bearing.
Other configurations and operations are the same as those of the first embodiment.

(Seventh embodiment)
The rolling bearing according to the seventh embodiment of the present invention shown in FIG. 18 has two rows of narrow ball bearings 10 as a front combination. In this embodiment, the contact angle is a reverse C shape, and the moment rigidity is reduced with respect to the rear combination. Therefore, if it is inevitable that the relative inclination of the inner ring 11 and the outer ring 12 during installation is unavoidable, Internally generated load can be reduced.
Other configurations and operations are the same as those of the first embodiment.

(Eighth embodiment)
The rolling bearing according to the eighth embodiment of the present invention shown in FIG. 19 has three rows of narrow ball bearings 10 as the back combination. In this embodiment, the rigidity and load capacity of the bearing can be improved.
Other configurations and operations are the same as those of the first embodiment.

(Ninth embodiment)
The rolling bearing according to the ninth embodiment of the present invention shown in FIG. 20 has four rows of narrow ball bearings 10 as the back combination. In this embodiment, the rigidity and load capacity of the bearing can be further improved.
Other configurations and operations are the same as those of the first embodiment.

(10th Embodiment)
The rolling bearing according to the tenth embodiment of the present invention shown in FIG. 21 is the same as the seventh embodiment shown in FIG. This is a double row narrow ball bearing 100 on the side opposite to the side. In this embodiment, the single row narrow ball bearing 10 can be replaced with two rows, and since the contact angle is a reverse C shape, the moment rigidity is reduced with respect to the rear combination. The cross-sectional dimension ratio (B2 / H2) between the axial cross-sectional width B2 and the radial cross-sectional height H2 (= (outer ring outer diameter D2-inner ring inner diameter d2) / 2) of the double row narrow ball bearing 100 is B2. /H2<1.2 is preferable, and more preferably, B2 / H2 <1.0 can be easily replaced with a standard size ball bearing.
Other configurations and operations are the same as those of the first embodiment.

(Eleventh embodiment)
The rolling bearing according to the eleventh embodiment of the present invention shown in FIG. 22 has two rows of outer rings 12 as an integrated outer ring 102 and has a contact angle of C with respect to that of the seventh embodiment shown in FIG. This is a double row narrow ball bearing 110 having a letter shape. In this embodiment, the single row narrow ball bearing 10 can be replaced with two rows, and since the contact angle is a square shape, the moment rigidity is increased with respect to the front combination. The sectional dimension ratio (B2 / H2) between the axial sectional width B2 and the radial sectional height H2 (= (outer ring outer diameter D2—inner ring inner diameter d2) / 2) of the double row narrow ball bearing 110 is B2. /H2<1.2 is preferable, and more preferably, B2 / H2 <1.0 can be easily replaced with a standard size ball bearing.
Other configurations and operations are the same as those of the first embodiment. A contact type or non-contact type seal member may be attached to both ends of the outer ring 102 in the axial direction.

(Twelfth embodiment)
The rolling bearing according to the twelfth embodiment of the present invention shown in FIG. 23 is the same as that of the second embodiment shown in FIG. The outer ring guide method is applied using the device 150. A cutting portion (not shown) is provided at at least one column portion (not shown) position in the circumferential direction of the machined cage 150. The setting method of the circumferential width ΔC of the cutting part is the same as that of the first embodiment.

  In the machined type retainer having a cutting portion as in this embodiment, the reduction in the guide clearance can be minimized, and problems such as biting on the guide surface can be prevented.

  In addition, this invention is not limited to embodiment mentioned above, A change, improvement, etc. are possible suitably. For example, cylindrical rollers may be used as rolling elements instead of balls.

Example 1
Here, a description will be given of a first embodiment in which the circumferential width ΔC of the cutting portion 14 is set for the retainer 15 incorporated in the two rows of rear combination angular contact ball bearings having the same structure as FIG.

The bearing specifications of this example are as follows.
<Bearing specifications>
・ With non-contact seal (2 locations only on the outer edge of the double row angular contact ball bearing)
Bearing dimensions: inner diameter φ170 mm, outer diameter φ215 mm, width 13.5 mm (single width), contact angle 35 °, ball diameter 6.35 mm, 80 balls, ball pitch circle diameter = φ192.5 mm, B / H = 0 .60
・ Cage shape: Crown type cage (ball guide method)
-Cage material: Polyamide 66 (no reinforcing material mixed), linear expansion coefficient: 80 × 10 ⁻⁶ (K ⁻¹ )
・ Inner ring, outer ring and ball material: bearing steel (SUJ2), linear expansion coefficient: 12.5 × 10 ⁻⁶ (K ⁻¹ )
・ Bearing preload: 500kgf (fixed position preload)

  In addition, the bearing temperature is set to 100 ° C. with respect to the average temperature: 20 ° C.

In this case, the circumferential width ΔC of the cut portion 14 is ΔC = 192.5π × (80-12.5) × 10 ⁻⁶ × 80 = 3.266 mm, and the circumferential width ΔC of the cut portion 14 is 3 .3 mm.

  Furthermore, you may add the predetermined | prescribed water absorption expansion part assumed by the resin material to be used to said (DELTA) C. The water absorption expansion can be set from, for example, an average moisture content (relative humidity 50%, 23 ° C. condition) assumed by the resin material used.

(Example 2)
Then, Example 2 by which the circumferential direction width | variety (DELTA) C of the cutting part 14 is set is demonstrated about the holder | retainer 15 which changed the following points about Example 1. FIG.

The changes of the bearing specifications of the present embodiment from the first embodiment are as follows.
<Bearing specifications>
・ Cage material: Polyamide 46 (+ 15% by weight of carbon fiber), linear expansion coefficient: 25 × 10 ⁻⁶ (K ⁻¹ )

In this case, the circumferential width ΔC of the cut portion 14 is ΔC = 192.5π × (25-12.5) × 10 ⁻⁶ × 80 = 0.604 mm, and the circumferential width ΔC of the cut portion 14 is 0. .6 mm is sufficient.

  The rolling bearings of the present invention are, for example, industrial machines, robot joints and turning mechanisms, machine tool spindles, rotary tables and spindle turning mechanisms, medical equipment, semiconductor / liquid crystal manufacturing equipment, optics and optoelectronic equipment, etc. It can utilize suitably for a rotation support part.

DESCRIPTION OF SYMBOLS 10 Rolling bearing 11a Inner ring raceway surface 11 Inner ring 12a Outer ring raceway surface 12 Outer ring 13 Rolling body 14 Cutting part 15 Cage 16 Seal member 17 Ring part 18 Column part 19 Pocket part

Claims (1)

An inner ring having an inner ring raceway surface on an outer peripheral surface, an outer ring having an outer ring raceway surface on an inner peripheral surface, a plurality of rolling elements provided rotatably between the inner ring raceway surface and the outer ring raceway surface, In a rolling bearing comprising a cut portion formed in at least one place in the circumferential direction, and a cage made of synthetic resin that holds the plurality of rolling elements at equal intervals in the circumferential direction,
The circumferential width dimension of the cut part is ΔC, the circumferential width dimension of one column part in the cut part is S ₁ , and the circumferential width dimension of the other column part in the cut part is S ₂ , A rolling bearing characterized by satisfying the relationship of S ₃ = S ₁ + S ₂ + ΔC when S ₃ is the circumferential width dimension of the uncut section of the cage, and ΔC is greater than zero.

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