JP2007100937A - Support unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a housing assembled with angular contact ball bearings in a support unit for back surface combination. <P>SOLUTION: The support unit comprises: two pieces of the angular contact ball bearing arranged in back surface combination; an outer ring pressing plate to fix two outer rings of the angular contact ball bearing which is fitted with the housing; and a check plate which is fixed on the housing and which locks respective inner ring outer side surfaces of the two inner rings of the angular contact ball bearing through the inner ring spacer or directly in the axial direction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a support unit that rotatably supports an end of a rotary shaft such as a screw shaft of a ball screw device provided in a mechanical device, a drive shaft or a driven shaft of the mechanical device.

In the conventional support unit, two angular contact ball bearings are arranged in a front combination that gives an inward contact angle, and the moment rigidity of the support unit is lowered to increase the tolerance for misalignment (for example, Patent Documents). 1).
FIG. 9 shows an example of a support unit in which such angular ball bearings are arranged in a front combination.

In FIG. 9, reference numeral 101 denotes a support unit.
Reference numerals 102 a and 102 b denote angular contact ball bearings, which are arranged in a front combination. Outer rings 103 a and 103 b are fitted into the housing 104 and fixed by an outer ring holding plate 105.
The inner rings 106a and 106b of the angular ball bearings 102a and 102b are fitted to the rotating shaft 107, and are respectively fixed to the shaft step portion 107a of the rotating shaft 107 by the lock nut 109 via the inner ring spacer 108.

  At this time, the inner ring inner surfaces of the inner rings 106a and 106b come into contact with each other by the axial pressing of the outer ring outer surfaces of the outer rings 103a and 103b by the outer ring holding plate 105 so that the ball 110 faces inward as shown in FIG. The contact point is pressed to give an appropriate preload, and the point of action becomes inside the angular ball bearings 102a and 102b, so that the distance between the points of action is reduced and the tolerance for misalignment is increased.

Reference numeral 111 denotes an oil seal, which is fixed to the housing 104 and the outer ring retainer plate 105 by press-fitting or the like. The lip portion is in sliding contact with the outer peripheral surface of the inner ring spacer 108, and dust enters from the outside of the support unit 101 and from the inside. Prevent leakage of lubricant.
In such a support unit 101, since the rotation shaft 107 is generally prepared by the customer, the state shown in FIG. 10A, that is, the state in which the rotation shaft 107, the inner ring spacer 108, and the lock nut 109 in FIG. It is assembled and supplied to the customer together with the inner ring spacer 108 and the lock nut 109.

It is to be noted that assembly without the inner ring spacer 108 is performed by moving the inner ring spacer 108 in the radial direction or dropping off in the axial direction due to vibration or the like during transportation in the support unit 101 in an assembled state. This is because the lip portion 111 may be damaged.
The customer fits one inner ring spacer 108 to the rotating shaft 107 to contact the shaft step portion 107a, inserts the rotating shaft 107 into the inner rings 106a and 106b of the angular ball bearings 102a and 102b, and fits the inner ring. 106a and 106b are fastened and fixed to the stepped portion 107a of the rotating shaft 107 via the other inner ring spacer 108 by a lock nut 109, and the housing 104 is fitted to a frame 112 of a mechanical device (not shown) so that the flange of the housing 104 is fitted. The support unit 101 is attached to a mechanical device (not shown) by fixing the portion 113 with a bolt or the like.
Japanese Patent Laying-Open No. 2003-74547 (page 4, paragraphs 0013-0015, FIG. 1)

  The front combination support unit described above has a large tolerance for misalignment, so it is effective when the rotation shaft of the drive device and the rotation shaft of the ball screw device, etc. are aligned and connected. When the rotating shaft of the device and the rotating shaft of a ball screw device, etc. are juxtaposed and rotated by a belt or the like, a moment due to the tension of the belt is applied to the support unit, so the front combined support unit with low moment rigidity As shown in FIG. 11 (b), the support unit of the rear combination in which the contact angle is increased by giving an outward contact angle to the two angular ball bearings is advantageous because the moment rigidity is higher. is there.

  However, in the case of the support unit of the rear combination, when trying to insert the rotation shaft into the inner ring, the inner ring of the angular ball bearing on the downstream side in the insertion direction is pushed outward, and the ball is inserted between the outer ring edge part and the inner ring edge part. Since the surface of the ball may be scratched by being pinched, it is difficult to supply the support unit with the angular ball bearing assembled to the housing like the front combination support unit, and the parts of the support unit are not assembled After fitting the inner ring of the angular ball bearing to the rotating shaft and fixing the rotating shaft to the step part of the rotating shaft via the inner ring spacer with the lock nut, the outer ring is mounted on the housing. It has to be fitted and fixed with an outer ring retainer plate, and then attached to the frame of the mechanical device, resulting in a problem that convenience for customers is reduced.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide means for supplying a customer with an angular ball bearing assembled to a housing even in a rear combination support unit.

  In order to solve the above problems, the present invention provides a support unit that is fixed to the two angular ball bearings arranged in a rear combination, a fixing member that fixes the two outer rings of the angular ball bearing, and the fixing member. An inner ring locking member for locking the inner ring outer surface of each of the two inner rings of the angular ball bearing in the axial direction is provided.

  As a result, the present invention can supply the customer with the angular ball bearing assembled to the housing even in the support unit of the rear combination, which can improve the convenience of the customer, and the front combination by the rear combination. As compared with the above, the moment rigidity can be increased, and the load capacity for the moment load when the rotating shaft is driven by a belt or the like can be increased.

  Embodiments of a support unit according to the present invention will be described below with reference to the drawings.

1 is a cross-sectional view showing a support unit according to the first embodiment, FIG. 2 is an enlarged cross-sectional view showing a portion A of FIG. 1, FIG. 3 is a front view showing the stopper plate of the first embodiment, and FIG. 1 is an enlarged cross-sectional view showing an angular ball bearing of Example 1. FIG.
In FIG. 1, reference numeral 1 denotes a support unit, which is a support unit in which two angular ball bearings 2a and 2b are arranged in a back surface combination.

As shown in FIG. 4, one angular ball bearing 2a arranged in the rear combination is formed on the outer ring raceway 4a formed on the inner peripheral surface of the outer ring 3a and having an approximately circular arc sectional shape on the outer peripheral surface of the inner ring 5a. A plurality of balls 7 are provided so as to be able to roll at a predetermined pitch between the formed inner ring raceway 6a having a substantially arc-shaped cross section in the axial direction.
On the inner peripheral surface of the outer ring 3a, the outer ring inner side surface 8a of the outer ring raceway 4a (the side surface on the left side in FIG. 4 and the side surface on the side of the angular ball bearing 2b when arranged in a rear combination) is referred to. The outer ring small-diameter portion 9a having a diameter substantially equal to the pitch circle diameter of the ball 7 is formed on the outer ring outer surface 10a side with an outer ring large-diameter portion 11a having a diameter slightly smaller than the valley diameter of the outer ring raceway 4a. An outer ring edge portion 12a is formed at a corner between 11a and the outer ring raceway 4a.

On the outer peripheral surface of the inner ring 5a, an inner ring small-diameter portion 15a having a diameter slightly larger than the valley diameter of the inner ring raceway 6a is formed on the inner ring inner surface 14a side of the inner ring raceway 6a, and the pitch circle diameter of the ball 7 on the inner ring outer surface 16a side. An inner ring large diameter portion 17a having substantially the same diameter is formed, and an inner ring edge portion 18a is formed at a corner between the inner ring small diameter portion 15a and the inner ring raceway 6a.
As described above, the outer ring edge portion 12a and the inner ring edge portion 18a are formed on the outer ring 3a and the inner ring 5a of the angular ball bearing 2a, respectively, so that the inner ring 5a is not dropped from the outer ring 3a when the angular ball bearing 2a is transported. Has been.

When a load is applied in the positive load direction indicated by the arrow B in FIG. 4, that is, in the direction of pushing the inner surface 8a of the outer ring and the outer surface 16a of the outer ring, the ball sandwiched between the outer ring track 4a and the inner ring track 6a. 7 is pressed against each track at a contact angle θ, and the direction of the action line C toward the axis CL (FIG. 1) is outward.
Further, as shown in FIG. 5, there is an axial gap δ between the ball 7 and the outer ring raceway 4a and the inner ring raceway 6a, and a load is applied in a direction opposite to the positive load direction (referred to as the anti-load direction). In other words, when a load is applied in a direction in which the outer ring outer surface 10a and the inner ring inner surface 14a are pushed, the ball 7 is in contact with the outer ring edge portion 12a and the inner ring edge portion 18a, that is, the axial gap δ. The ball 7 is smoothly moved while the ball 7 is moved, but the ball 7 is scratched by being caught between the outer ring edge portion 12a and the inner ring edge portion 18a and riding on each edge portion.

As described above, the axial clearance δ is a play in the axial direction of a so-called ball bearing, and is defined as a clearance in which the ball 7 does not ride on the outer ring edge portion 12a and the inner ring edge portion 18a if less than this. It is set according to the specifications of the bearing.
The same applies to the other angular ball bearing 2b. In this case, the outer ring small-diameter portion 9b and the like are reversed in the illustrations of FIGS.

In FIG. 1, reference numeral 21 denotes a rotating shaft, for example, a screw shaft of a ball screw device provided in a mechanical device (not shown), and the inner peripheral surfaces of the inner rings 5a and 5b of the angular ball bearings 2a and 2b are fitted.
22a and 22b are inner ring spacers, which are made of a steel material such as alloy steel, and are provided with contact surfaces 24 that contact the inner ring outer surfaces 16a and 16b, respectively. The inner ring 5 a, 5 b is clamped between the shaft step portion 21 a of the rotary shaft 21 and fixed by tightening a lock nut 23 that is screwed into a screw portion formed at the end of 21.

  Reference numeral 25 denotes a housing, which is a cylindrical member made of a steel material such as alloy steel, and has a fitting hole 26 fitted to the outer peripheral surface of the outer rings 3a and 3b of the angular ball bearings 2a and 2b on the inner peripheral surface thereof. And a locking portion 27 for locking the outer ring outer surface 10b of one outer ring 3b is formed. A flange portion 28 is integrally formed on the outer peripheral surface of the locking portion 27 and is illustrated by a stepped bolt hole 29 provided in the flange portion 28. It is fixed to the frame of the machine with bolts.

Reference numeral 30 denotes an outer ring retainer plate, which is a donut plate-like member made of a steel material such as alloy steel. The outer ring outer surface 10a of the other outer ring 3a is locked by pressing and the outer rings 3a and 3b are fixed to the housing 25. It has a function to do.
Reference numeral 31 denotes a stop plate, which is a donut-shaped plate member made of a steel material such as an alloy steel. As shown in FIG. 2, a cylindrical inner ring spacer 22a has an end portion on the opposite side of the contact surface 24. A fitting hole 34 that loosely fits in the fitting surface 33 of the formed fitting step portion 32 via a radial gap smaller than the difference between the radius of the fitting surface 33 and the radius of the outer peripheral surface of the inner ring spacer 22a; In order to avoid interference with the lock nut 23, the central portion around the fitting hole 34 is provided with a wall surface 35 of the fitting step portion 32 and a locking surface 36 that opposes through a slight axial gap X. It is formed by bending toward the inner ring spacer 22a.

  Further, the stop plate 31 is formed in a donut plate shape and then divided in the radial direction by a cutter such as a thin grindstone, and the angular ball bearing 2b side is directly connected to the angular ball bearing 2 by the mounting holes 37 formed respectively. The 2a side is fixed to the screw hole of the housing 25 by a bolt 38 via the outer ring presser 30. Accordingly, the stop plate 31 is configured to be disassembled after the support unit 1 is attached to the mechanical device.

The stop plate 31 of the present embodiment is formed by being divided into two in the diameter direction as shown in FIG.
The slight axial gap X is set to be equal to or less than the axial gap δ, which is play of one angular ball bearing, for example, the angular ball bearing 2a, when the stopper plate 31 is fixed to the housing 25. The same applies to the angular ball bearing 2b side.
Reference numeral 39 denotes an oil seal, which is fixed to the housing 25 and the outer ring retainer plate 30 by press-fitting or the like. The lip portions are in sliding contact with the outer peripheral surfaces of the inner ring spacers 22a and 22b, and dust enters from the outside of the support unit 1. And prevent leakage of lubricant from inside.

The inner ring locking member of the present embodiment is constituted by the stop plates 31 disposed on both sides of the angular ball bearings 2a, 2b and the inner ring spacers 22a, 22b fitted to the angular ball bearings 2a, 2b. The fixing members for the outer rings 3a and 3b of the embodiment are configured.
The operation of the above configuration will be described.
The support unit 1 in which the angular ball bearings 2a and 2b of the present embodiment are arranged in the rear combination is similar to the support unit 101 in which the angular ball bearings 102a and 102b described above are arranged in the front combination, and the rotating shaft 21 in FIG. And assembled without the lock nut 23 and supplied to the customer together with the lock nut 23.

  The customer inserts and fits the rotary shaft 21 into the inner ring spacer 22b of the support unit 1 supplied in the assembled state, the inner rings 5a and 5b of the angular ball bearings 2a and 2b, and the inner ring spacer 22a, and the inner rings 5a and 5b are fitted. The lock nut 23 is fixed to the shaft step portion 21a of the rotary shaft 21 with the specified tightening torque via the inner ring spacers 22a and 22b, and the housing 25 is fitted to a frame or the like of a mechanical device (not shown). The 25 flange portions 28 are fixed with bolts or the like using stepped bolt holes 29, and the support unit 1 is attached to a mechanical device (not shown). After removing the stop plate 31 that can be disassembled in two parts, the rotation is performed. The rotation operation of the shaft 21 is started.

  As described above, the support unit 1 according to the present embodiment is transported in a state where the outer ring inner surfaces 8a and 8b of the outer rings 3a and 3b are in contact with each other by axial pressing by the outer ring holding plate 30, and is locked when mounted on a mechanical device. 23 is tightened with a prescribed tightening torque, and when the inner ring outer surfaces 16a, 16b of the inner rings 5a, 5b are pressed through the inner ring spacers 22a, 22b, the ball 7 has an outward contact angle θ shown in FIG. And an appropriate preload is applied, and as shown in FIG. 11 (b), the action point becomes outside the angular ball bearings 2a, 2b, the distance between the action points is increased, and the moment rigidity is increased.

  When the rotary shaft 21 is inserted, even if the rotary shaft 21 pushes the inner circumferential surface of the inner ring 5a of the angular ball bearing 2a existing downstream in the insertion direction of the rotary shaft 21 in the insertion direction, Since the locking surface 36 is opposed to the wall surface 35 of the fitting step portion 32 of the inner ring spacer 22a via the axial gap X which is equal to or less than the axial gap δ which is play of the angular ball bearing 2a, the inner ring 5a is The ball 7 is locked by the locking surface 36 before the ball 7 is clamped between the outer ring edge portion 12a and the inner ring edge portion 18a by moving in the direction gap δ, and the ball 7 rides on the outer ring edge portion 12a and the inner ring edge portion 18a. The surface of the ball 7 is not damaged.

Further, the inner ring spacers 22a and 22b are loosely fitted into the fitting holes 34 of the stop plate 31 by the fitting surface 33 of the fitting step portion 32, and the wall surface 35 and the locking surface 36 face each other with the axial gap X therebetween. Therefore, the inner ring spacers 22a and 22b do not fall off during transportation of the assembled support unit 1, and the lip portion of the oil seal 39 is not damaged.
As described above, in this embodiment, the inner ring outer surface of each of the inner rings of the two angular ball bearings arranged in the combination of the rear surfaces is locked in the axial direction by the inner ring spacer and the stop plate. Even in the combination support unit, the angular ball bearings can be supplied to the customer with the housing assembled, improving the convenience of the customer and increasing the rigidity of the moment by the rear combination compared to the front combination. It is possible to increase the load capacity against moment load when the rotating shaft is driven by a belt or the like.

In addition, since the stop plate is divided in the diametrical direction, the stop plate is configured to be disassembled after the support unit is assembled to the mechanical device, and causes interference with other parts such as a lock nut and a rotary shaft. The stop plate can be easily removed without any trouble.
In this embodiment, the wall surface of the fitting step portion of the inner ring spacer and the locking surface of the stopper plate are opposed to each other via the axial gap X. However, the axial gap X is set to “0”. You may make it assemble in the state which contacted the locking surface to the wall surface, ie, the state which pressed the wall surface with the locking surface. In this way, the movement of the inner ring spacer during transportation can be further lightened.

  Further, although the description has been given assuming that the stop plate is removed before the rotation operation of the rotating shaft, the rotation operation may be performed without removing the stop plate. The wall surface of the fitting step portion of the inner ring spacer of this embodiment and the locking surface of the stopper plate are opposed to each other with a slight axial gap X, and the fitting hole of the stopper plate is fitted to the fitting step portion. Since it is loosely fitted to the surface via a radial gap, this part can function as a labyrinth seal, the oil seal can be omitted, the support unit can be simplified, and it can be rotated by a non-contact seal. The drive loss of the shaft can be reduced.

  In this case, it is necessary to divide the stop plate so that no gap is formed in the diametrically divided portion, and if the stop plate is not divided into one donut-shaped plate, the number of manufacturing steps of the stop plate is reduced. It becomes possible.

FIG. 6 is a cross-sectional view illustrating a support unit according to the second embodiment.
In addition, the same part as the said Example 1 attaches | subjects the same code | symbol, and abbreviate | omits the description.
In FIG. 6, reference numeral 41 denotes a stop plate, which is a flat donut-shaped plate member made of a steel material such as alloy steel, and has an inner diameter that fits loosely on the outer peripheral surface of the shaft step portion 21 a of the rotating shaft 21. It functions as a joint hole 42, and the surface on the housing 25 side locks the side surface on the opposite side of the contact surface 24 that contacts the inner ring outer surface 16a, 16b of the inner ring spacer 43 formed in a cylindrical shape by pressing. It functions as a locking surface 44.

Further, the stop plate 41 is divided in the diametrical direction in the same manner as in the first embodiment, and is fixed to the housing 25 by a bolt 38 inserted into the mounting hole 37.
The chamfering of the corner between the outer peripheral surface of the inner ring spacer 43 and the side surface on the side of the stop plate 41 is performed to chamfer the inner ring spacer 108 shown in FIG. It is formed smaller than.

The inner ring locking member of this embodiment is constituted by inner ring spacers 43 disposed on both sides of the angular ball bearings 2a and 2b and stop plates 41 that press the inner ring spacers. The fixing members of the outer rings 3a and 3b are the housing 25 and the outer ring. The presser plate 30 is configured.
The operation of the above configuration will be described.
The support unit 1 in which the angular ball bearings 2a and 2b of the present embodiment are arranged in the rear combination is assembled in a state excluding the rotating shaft 21 in FIG. 6 and supplied to the customer together with the lock nut 23.

  The customer inserts and fits the rotary shaft 21 into the inner ring spacer 43 of the support unit 1 and the inner rings 5a and 5b of the angular ball bearings 2a and 2b and the inner ring spacer 43 supplied in the assembled state, and removes the stop plate 41. After that, the inner rings 5a and 5b are respectively fixed to the shaft step portion 21a of the rotating shaft 21 through the inner ring spacer 43 by tightening the lock nut 23 with a predetermined tightening torque, and the housing 25 is not shown in the frame of a mechanical device (not shown). The support unit 1 is attached to a mechanical device (not shown) by fixing the flange portion 28 of the housing 25 with a bolt or the like using the stepped bolt hole 29.

  As described above, the support unit 1 according to the present embodiment abuts the outer ring inner surfaces 8a and 8b of the outer rings 3a and 3b by axial pressing by the outer ring holding plate 30, and the inner rings 5a and 5b via the inner ring spacer 43. When it is transported with a slight preload applied to the angular ball bearings 2a and 2b by being pressed by the presser plate 41, and when the lock nut 23 is tightened with a prescribed tightening torque when mounted on the mechanical device as in the first embodiment. Appropriate preload is applied, and the distance between the action points is increased to increase the moment stiffness.

  Even when the rotating shaft 21 pushes the inner peripheral surface of the inner ring 5a of the angular ball bearing 2a existing downstream in the inserting direction of the rotating shaft 21 in the inserting direction when the rotating shaft 21 is inserted, the stop plate 41 Since the locking surface 44 presses the inner ring outer surfaces 16a and 16b via the inner ring spacer 43, the inner rings 5a and 5b do not move. This prevents the ball 7 from getting on the outer ring edge portion 12a and the inner ring edge portion 18a and damaging the surface of the ball 7.

  Further, since the inner ring spacer 43 is pressed by the stop plate 41 and is transported with preload applied to the angular ball bearings 2a and 2b, the inner ring spacer 43 is dropped when the assembled support unit 1 is transported. The lip portion of the oil seal 39 is not damaged, and the ball 7 and the outer ring raceway 4a and the inner ring raceway 6a do not collide with each other due to an unexpected impact or the like at the time of transportation, so that an indentation or the like does not occur.

  As described above, in the present embodiment, the inner ring outer surface of each of the inner rings of the two angular ball bearings arranged in the back combination is pressed in the axial direction by the stopper plate via the inner ring spacer. The effect similar to the said Example 1 can be acquired, and since the preload is given to the angular ball bearing at the time of transport by the stop plate, it prevents beforehand that an unexpected damage | wound arises in an angular ball bearing or an oil seal. be able to.

  In this embodiment, the stopper plate is described as having the same shape. However, for example, the inner diameter of the fitting hole of the stopper plate on the outer ring retainer plate side is loosely fitted to the outer shape of the screw portion to which the lock nut of the rotary shaft is screwed. You may make it form irregularly as a diameter to do.

FIG. 7 is a cross-sectional view illustrating a support unit according to the third embodiment.
In addition, the same part as the said Example 1 attaches | subjects the same code | symbol, and abbreviate | omits the description.
In FIG. 7, reference numeral 51 denotes a stop plate as an inner ring locking member of the present embodiment, a cylindrical portion 52 made of a steel material such as alloy steel, and a flange extending in the radial direction provided at one end thereof. The end surface of the other end of the cylindrical portion 52 functions as a locking surface 54 that locks the inner ring outer surfaces 16a and 16b of the inner rings 5a and 5b of the angular ball bearings 2a and 2b by pressing.

Further, the stop plate 51 is divided in the diameter direction in the same manner as in the first embodiment, and is fixed to the housing 25 by a bolt 38 inserted into the mounting hole 37.
The fixing members for the outer rings 3a and 3b of the present embodiment are constituted by the housing 25 and the outer ring pressing plate 30.
The operation of the above configuration will be described.

The support unit 1 in which the angular ball bearings 2a and 2b of the present embodiment are arranged in the rear combination is assembled in a state excluding the rotating shaft 21 in FIG. 7, and the lock nut 23 and the axial dimension are the inner ring spacer 43 of the second embodiment. Are supplied to the customer together with an inner ring spacer (not shown) which is twice as large as the axial dimension of the oil seal 39 and an oil seal (not shown) which is in sliding contact with the outer periphery of the rotary shaft 21.
The customer inserts the rotating shaft 21 into an oil seal (not shown), inserts the rotating shaft 21 into the inner rings 5a and 5b of the angular ball bearings 2a and 2b of the support unit 1 supplied in the assembled state, and stops. After removing the plate 51, an oil seal (not shown) is pressed into the housing 25 and an oil seal 39 is press-fitted into the outer ring retainer plate 30, an inner ring spacer (not shown) is inserted into the rotary shaft 21, and the inner rings 5a and 5b are connected to the shaft stage of the rotary shaft 21. The lock nut 23 is fixed to the portion 21a by tightening with a predetermined tightening torque, and the housing 25 is fitted to a frame of a mechanical device (not shown), and the flange portion 28 of the housing 25 is bolted using the stepped bolt hole 29. The support unit 1 is fixed to a mechanical device (not shown) by being fixed by, for example.

  As described above, the support unit 1 according to the present embodiment causes the inner surfaces 8a and 8b of the outer rings 3a and 3b to contact each other by pressing in the axial direction by the outer ring pressing plate 30, and presses the inner rings 5a and 5b by the pressing plate 51. The angular ball bearings 2a and 2b are transported with a slight preload applied thereto, and when the lock nut 23 is tightened with a specified tightening torque at the time of mounting to the mechanical device as in the first embodiment, an appropriate preload is applied. The distance between the action points increases and the moment stiffness increases.

  Even when the rotating shaft 21 pushes the inner peripheral surface of the inner ring 5a of the angular ball bearing 2a existing downstream in the inserting direction of the rotating shaft 21 in the inserting direction when the rotating shaft 21 is inserted, the stop plate 51 Since the locking surface 54 presses the inner ring outer surfaces 16a and 16b of the inner rings 5a and 5b of the angular ball bearings 2a and 2b, the inner rings 5a and 5b do not move. This prevents the ball 7 from getting on the outer ring edge portion 12a and the inner ring edge portion 18a and damaging the surface of the ball 7.

Further, since the angular ball bearings 2a and 2b are transported in a state where a preload is applied by the pressing by the stop plate 51, the ball 7, the outer ring raceway 4a and the inner ring raceway 6a are brought together during transportation of the assembled support unit 1 or the like. There will be no indentation due to collisions caused by unexpected impact during transportation.
As described above, in the present embodiment, the inner ring outer surfaces of the inner rings of the two angular ball bearings arranged in the rear combination are pressed in the axial direction by the stop plate, and thus the same as in the first embodiment. In addition, since the preload is applied to the angular ball bearing during transportation by the stop plate, it is possible to prevent the angular ball bearing and the oil seal from being damaged unexpectedly.

FIG. 8 is a cross-sectional view illustrating a support unit according to the fourth embodiment.
In addition, the same part as the said Example 1 attaches | subjects the same code | symbol, and abbreviate | omits the description.
In FIG. 8, reference numeral 61 denotes a stop plate, which is a conically expanding cone for avoiding interference between a cylindrical portion 62 made of a steel material such as alloy steel and a lock nut 23 provided at one end thereof. It is comprised by the part 63 and the collar part 64 extended in the radial direction provided in the edge part on the opposite side of the cylindrical part 62 of the cone part 63. As shown in FIG.

The end surface of the other end of the cylindrical portion 62 is opposed to the inner ring outer surfaces 16a and 16b of the inner rings 5a and 5b of the angular ball bearings 2a and 2b via a gap larger than the set axial gap X. .
Reference numeral 66 denotes an inner ring spacer, which is a cylindrical member made of a steel material such as alloy steel having an abutment surface 24 that abuts against the inner ring outer surfaces 16a and 16b. A plurality of circumferential grooves 67 are formed so as to fit into circumferential protrusions 68 provided on the inner peripheral surface of the cylindrical portion 62 of the stopper plate 61.

Further, the axial clearances of the circumferential groove 67 and the circumferential protrusion 68 on the angular ball bearings 2a, 2b side are set to the axial clearance X, and the surfaces of the circumferential protrusion 68 on the angular ball bearings 2a, 2b side are respectively set. In addition to functioning as a locking surface, a labyrinth seal is constituted by a circumferential protrusion 68 that is loosely fitted in the circumferential groove 67.
Further, the stop plate 61 is divided in the diametrical direction and fixed to the housing 25 by bolts 38 inserted into the attachment holes 37, and is divided so that no gap is formed in the divided portion when fixed.

The inner ring locking member of the present embodiment is constituted by an inner ring spacer 66 disposed on both sides of the angular ball bearings 2a, 2b and a retaining plate 61 having a circumferential protrusion 68 that is loosely fitted in the circumferential groove 67 thereof. The fixing members 3a and 3b are constituted by the housing 25 and the outer ring pressing plate 30.
The operation of the above configuration will be described.

The support unit 1 in which the angular ball bearings 2a and 2b of the present embodiment are arranged in the rear combination is assembled in a state excluding the rotary shaft 21 and the lock nut 23 in FIG. 8 and supplied to the customer together with the lock nut 23.
The customer inserts the rotary shaft 21 into the inner ring spacer 66 of the support unit 1 supplied in the assembled state, the inner rings 5a and 5b of the angular ball bearings 2a and 2b, and the inner ring spacer 66, and fits the inner rings 5a and 5b. The lock nut 23 is fixed to the shaft step portion 21a of the rotating shaft 21 with a predetermined tightening torque, and the housing 25 is fitted to a frame of a mechanical device (not shown), and the flange portion 28 of the housing 25 is connected to the step bolt. The support unit 1 is attached to a mechanical device (not shown) by being fixed with bolts or the like using the holes 29, and the rotation operation of the rotary shaft 21 is started in the state as it is.

As described above, the support unit 1 of the present embodiment is transported in a state in which the outer ring inner surfaces 8a and 8b of the outer rings 3a and 3b are in contact with each other by axial pressing by the outer ring holding plate 30. When the lock nut 23 is tightened with a predetermined tightening torque during the mounting to an appropriate pressure, an appropriate preload is applied, and the distance between the operating points is increased to increase the moment rigidity.
When the rotary shaft 21 is inserted, even if the rotary shaft 21 pushes the inner peripheral surface of the inner ring 5a of the angular ball bearing 2a existing downstream in the insertion direction of the rotary shaft 21 in the insertion direction, Since the engaging surface of the circumferential protrusion 68 faces the facing surface of the circumferential groove 67 of the inner ring spacer 66 via the axial gap X, the inner ring 5a moves in the axial gap δ, and the ball 7 Before being sandwiched between the outer ring edge portion 12a and the inner ring edge portion 18a, the ball 7 is locked by the locking surface, and the ball 7 does not ride on the outer ring edge portion 12a or the inner ring edge portion 18a, and the surface of the ball 7 is damaged. Nor.

  Further, since the labyrinth seal is formed by the circumferential projection 68 of the stopper plate 61 that is loosely fitted in the circumferential groove 67 of the inner ring spacer 66, the oil seal is omitted and the support unit 1 can be simplified. In addition, the drive loss of the rotating shaft can be reduced by the non-contact seal, and after the support unit 1 is attached to the mechanical device, the rotation operation can be started immediately without removing the stop plate 61.

  As described above, in the present embodiment, the two annular ball bearings arranged in combination on the back face are opposed to the locking surfaces of the circumferential protrusions of the circumferential grooves of the inner ring spacer that are in contact with the inner ring outer surfaces of the inner rings. Since the surface is locked by the locking surface of the circumferential protrusion of the stopper plate, the same effect as in the first embodiment can be obtained, and the stopper plate loosely fitted in the circumferential groove of the inner ring spacer Since the labyrinth seal is formed by the circumferential projection, the support unit can be simplified by omitting the oil seal, and the drive loss of the rotating shaft can be reduced by the non-contact seal.

  In each of the above embodiments, the stop plate is described as being made of steel. However, the material of the stop plate is not limited to the above, and may be a resin material or the like. In short, any material may be used as long as the inner ring is locked during transportation and the axial gap can be kept below the axial gap δ.

Sectional drawing which shows the support unit of Example 1. FIG. 1 is an enlarged sectional view showing part A of FIG. The front view seen from the housing side which shows the stopper plate of Example 1 1 is an enlarged cross-sectional view showing an angular ball bearing of Example 1. FIG. It is an expanded sectional view which shows the anti-load state of the angular ball bearing of Example 1. Sectional drawing which shows the support unit of Example 2. Sectional drawing which shows the support unit of Example 3 Sectional drawing which shows the support unit of Example 4. Sectional view showing a front combination support unit Explanatory drawing showing the method of assembling the front combination support unit Explanatory drawing showing how to combine angular contact ball bearings

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,101 Support unit 2a, 2b, 102a, 102b Angular contact ball bearing 3a, 3b, 103a, 103b Outer ring 4a, 4b Outer ring raceway 5a, 5b, 106a, 106b Inner ring 6a, 6b Inner ring raceway 7, 110 Ball 8a, 8b In outer ring Side surface 9a, 9b Outer ring small diameter part 10a, 10b Outer ring outer side face 11a, 11b Outer ring large diameter part 12a, 12b Outer ring edge part 14a, 14b Inner ring inner side face 15a, 15b Inner ring small diameter part 16a, 16b Inner ring outer side face 17a, 17b Inner ring large diameter Part 18a, 18b Inner ring edge part 21, 107 Rotating shaft 21a, 107a Shaft step part 22a, 22b, 43, 66, 108 Inner ring spacer 23, 109 Lock nut 24 Contact surface 25, 104 Housing 26 Fitting hole 27 Locking Part 28, 113 flange part 29 stepped bolt hole 30, 05 Outer ring retainer plate 31, 41, 51, 61 Stop plate 32 Fitting step 33 Fitting surface 34, 42 Fitting hole 35 Wall surface 36, 44, 54 Locking surface 37 Mounting hole 38 Bolt 39, 111 Oil seal 52, 62 cylindrical portion 53, 64 collar portion 63 conical portion 67 circumferential groove 68 circumferential projection 112 frame X axial clearance δ axial clearance (play in the axial direction of the ball bearing)

Claims (6)

  Two angular contact ball bearings arranged in combination on the back, a fixing member for fixing two outer rings of the angular ball bearing, and fixed to the fixing member, the inner ring outer surface of each of the two inner rings of the angular ball bearing is pivoted A support unit comprising an inner ring locking member that locks in a direction. In claim 1,
The support unit, wherein the inner ring is opposed to the inner ring locking member with a slight axial gap. In claim 1 or claim 2,
The support unit, wherein the inner ring locking member is divided in a radial direction. In claim 1,
The inner ring locking member is fixed to the fixing member and an inner ring spacer having a contact surface that contacts the outer surface of the inner ring and a fitting step formed on an end opposite to the contact surface. A support unit comprising: a stop plate having a fitting hole that loosely fits to a fitting surface of the fitting step portion and a locking surface that locks a wall surface of the fitting step portion. In claim 4,
A support unit, wherein a wall surface of the fitting step portion and a locking surface of the stop plate are opposed to each other with a slight axial gap. In claim 4 or claim 5,
The support unit, wherein the stop plate is divided in a radial direction.