CN111795077A

CN111795077A - Bearing preloading device

Info

Publication number: CN111795077A
Application number: CN202010515556.XA
Authority: CN
Inventors: 徐旭松; 叶超; 朱敏浩; 孙志英
Original assignee: Jiangsu University of Technology
Current assignee: Jiangsu University of Technology
Priority date: 2020-06-09
Filing date: 2020-06-09
Publication date: 2020-10-20
Anticipated expiration: 2040-06-09
Also published as: CN111795077B

Abstract

The invention relates to a bearing pre-tightening device which comprises a bearing, a bearing seat, an inclined sleeve, a sleeve ring, a step shaft and a cover plate, wherein a bearing inner ring and the step shaft are installed in a matched mode, an outer ring of the bearing and the inclined sleeve inner ring are installed in an interference fit mode, the outer side of the inclined sleeve is installed in a matched mode with the sleeve ring inner ring, the outer surface of the inclined sleeve is conical, the shape of the sleeve ring inner ring corresponds to that of the outer surface of the inclined sleeve, the sleeve ring outer ring is arranged in the bearing seat in a sliding mode, the cover plate is fixedly arranged on two sides of the bearing seat, the cover plate is matched with the step shaft and used for axially fixing the bearing inner ring, the cover plate is also used for abutting against the outer ring of one end, with a smaller size, of the bearing, close. The invention not only enlarges the pre-tightening range, but also can reduce the pre-tightening cost.

Description

Bearing preloading device

Technical Field

The invention relates to the technical field of bearing pre-tightening, in particular to a bearing pre-tightening device.

Background

The pre-tightening of the rolling bearing is to adopt a proper method to generate certain pre-deformation between the rolling body and the inner and outer rings of the bearing so as to keep the inner and outer rings of the bearing in a compact state and enable the bearing to operate with negative clearance or zero clearance. The bearing has the best play of zero or negative play in a normal working state, can ensure the rotation precision of the shaft to the maximum extent, reduces the vibration and noise of the shaft and prolongs the service life of the bearing. In the prior art, pre-tightening of a bearing before working is mostly realized by applying a certain load to the bearing by using opposite acting force on a sleeve through the interaction relation of forces by adopting a purely mechanical method; the bearing pre-tightening amount is controlled by utilizing the property of the heated material, the pre-tightening effect of the prior art can be well reflected, but the artificial error is large, the efficiency is low, the pre-tightening of the bearing needs to well meet the requirement of the rotation precision during normal work, so the control of the pre-tightening precision is also important, most of the prior bearings are installed on the shaft for pre-tightening, and the automatic pre-tightening device is a little large and high in cost for the current normal shaft, the process during operation is not well controlled, and the overlarge hysteresis error is easily caused.

Disclosure of Invention

The invention provides a bearing pre-tightening device for solving the problems that the prior bearing pre-tightening is high in cost and difficult to control and is easy to cause overlarge hysteresis error, which comprises a bearing, a bearing seat, an inclined sleeve, a sleeve ring, a step shaft and a cover plate, wherein an inner ring of the bearing is matched and installed with the step shaft, an outer ring of the bearing is in interference fit with the inner ring of the inclined sleeve, the outer side of the inclined sleeve is matched and installed with the inner ring of the sleeve ring, the outer surface of the inclined sleeve is conical, the shape of the inner ring of the sleeve ring is corresponding to that of the outer surface of the inclined sleeve, the outer ring of the sleeve ring is arranged in the bearing seat in a sliding manner, the cover plate is fixedly arranged on each of two sides of the bearing seat, the cover plate is matched with the step shaft and is used for axially fixing the inner ring of the bearing, the cover plate is also used for abutting against the outer ring at, the pre-tightening mechanism is arranged on the cover plate close to one end, with the larger size, of the outer side of the inclined sleeve.

Preferably, the cover plate is divided into a front cover plate and a rear cover plate, the front cover plate is located at one end, with the larger size, of the outer side of the inclined sleeve, the pre-tightening mechanism is arranged on the front cover plate, a first protrusion and a second protrusion are arranged on the rear cover plate, the first protrusion is used for abutting against the bearing inner ring, and the second protrusion is used for abutting against the bearing outer ring. A first bulge and a second bulge are arranged on one rear cover plate, the front cover plate is used for placing a pre-tightening mechanism, and the first bulge is matched with the step of the step shaft to abut against the inner ring of the bearing. The back shroud sets up the less one end of the cover outside size to one side, the cover passes through the conical surface cooperation motion with the lantern ring to one side, and the back shroud has supported the outer lane of bearing one side, pretension mechanism promotes the outer lane of bearing opposite side, when exerting force to the back shroud direction, the cover takes the bearing to the less direction removal of cover size to one side, because the lantern ring sets up in the bearing frame, the bearing frame has restricted the lantern ring to the direction motion of keeping away from the bearing, make the lantern ring exert force for the cover to one side, radial force is exerted for the bearing to the cover to one side, for the bearing, bearing radial direction receives the extrusion force, axial direction receives bearing thrust, thereby adjust the radial force and the axial.

Furthermore, the cover plate is divided into a front cover plate and a rear cover plate, the front cover plate is located at one end, with the larger size, of the outer side of the inclined sleeve, the pre-tightening mechanism is arranged on the front cover plate, a first bulge used for abutting against the bearing inner ring is further arranged on the front cover plate, and a second bulge used for abutting against the bearing outer ring is arranged on the rear cover plate. The front cover plate is used for placing the pre-tightening mechanism and the first bulge which is propped against the bearing inner ring, and the rear cover plate is provided with the second bulge. The bearing inner ring is fixed by the cooperation of the first bulge and the step shaft, the bearing is in interference fit with the inclined sleeve, the conical inclined sleeve moves in cooperation with the sleeve ring, the second bulge is arranged on the rear cover plate and props against the outer ring on one side of the bearing, the rear cover plate is located at one end with a smaller size of the inclined sleeve, the pre-tightening mechanism pushes the bearing outer ring, the bearing is in interference fit with the inclined sleeve, the bearing drives the inclined sleeve to move towards the direction of the rear cover plate, the sleeve ring is arranged in the bearing seat, the sleeve ring is limited by the bearing seat due to the fact that the sleeve ring and the inclined sleeve move in a matching mode through the conical surface, the sleeve ring cannot move towards the direction far away from the bearing, and therefore the radial force is exerted on the inclined sleeve by the sleeve ring, the radial force is exerted on the bearing by the second bulge of the rear cover plate and props against the outer.

Preferably, a first gasket is arranged between the front cover plate and the inclined sleeve, and a second gasket is arranged between the rear cover plate and the bearing seat. The first gasket and the second gasket can buffer the screwing pressure of the screw on the bearing seat on one hand, and can compensate the heated elongation of the step shaft during high-speed rotation on the other hand.

Further, the pre-tightening mechanism comprises a motor, a driving gear, two driven gears and two screws, the motor is installed on the front cover plate, the driving gear is fixed on a motor shaft of the motor, two sides of the driving gear are meshed with the two driven gears, the two driven gears are fixedly connected with the two screws respectively, the two screws are rotatably arranged on the front cover plate and are connected with nuts, the two nuts are fixedly connected with a connecting rod, springs are sleeved on the screws, the length of each screw is smaller than that of the spring in a natural state, one end of each spring abuts against the corresponding nut, the other end of each spring abuts against the outer ring of the bearing, and a sensor for detecting the spring expansion amount is further arranged on each nut. The connecting rod limits the nut to rotate on the screw rod, so that the nut can only move in a straight line. The spring is sleeved on the screw rod, so that the movement of the spring is limited, and the spring can only move linearly along the length direction of the screw rod. The length of the screw rod is smaller than that of the spring in a natural state, so that the spring can push the outer ring of the bearing, the screw rod is not contacted with the outer ring of the bearing all the time, the stretching amount of the spring is detected through the sensor, the original length and stiffness coefficient of the spring are known, and the pre-tightening force applied to the axial direction of the bearing can be calculated according to the stretching amount.

Preferably, in order to make the axial forces received by the bearing outer ring in the circumferential direction uniform, the number of the pre-tightening mechanisms is two, and the two pre-tightening mechanisms are symmetrically arranged around the bearing seat axis.

Furthermore, the motor is arranged on one surface, far away from the bearing, of the front cover plate, and a motor shaft of the motor penetrates through the cover plate and is fixedly connected with the driving gear.

Preferably, the cover plate is fixed to the bearing housing by screws.

Has the advantages that: 1. compared with most of pre-tightening modes, the mode can simultaneously complete the pre-tightening of the bearings in the radial direction and the axial direction, so that the pre-tightening range is expanded, and the pre-tightening cost can be reduced.

2. The pre-tightening mode of the invention can be separated from manual pre-tightening by motor control, realizes automatic pre-tightening, not only improves pre-tightening efficiency, but also can be controlled at any time in the pre-tightening process, and can deal with emergency situations during pre-tightening.

3. Some pre-tightening components can realize pre-tightening by using chemical and physical properties such as material property, centrifugal force and the like, but the pre-tightening precision is insufficient due to insufficient working condition, so that the pre-tightened bearing cannot meet the actual requirement.

Drawings

FIG. 1 is a cross-sectional view of a first embodiment of the overall structure of the present invention;

FIG. 2 is a cross-sectional view of a second embodiment of the overall structure of the present invention;

FIG. 3 is a schematic view of a pretensioning mechanism according to the present invention;

FIG. 4 is an enlarged view taken at A in FIG. 3;

FIG. 5 is an exploded view of the present invention;

1. a bearing; 2. a bearing seat; 3. a step shaft; 4. a rear cover plate; 5. a front cover plate; 6. a collar; 7. a first protrusion; 8. a second protrusion; 9. a first gasket; 10. a second gasket; 11. a motor; 12. a driving gear; 13. a nut; 14. a spring; 15. a connecting rod; 16. a screw; 17. a screw; 18. a step; 19. an inclined sleeve; 20. a driven gear.

Detailed Description

Example one

As shown in the figure, the bearing pre-tightening device comprises a bearing 1, a bearing seat 2, an inclined sleeve 19, a sleeve ring 6, a step shaft 3 and a cover plate, wherein an inner ring of the bearing 1 is installed in a matched manner with the step shaft 3, an outer ring of the bearing 1 is installed in an interference fit manner with an inner ring of the inclined sleeve 19, the outer side of the inclined sleeve 19 is installed in a matched manner with the inner ring of the sleeve ring 6, the outer surface of the inclined sleeve 19 is conical, the shape of the inner ring of the sleeve ring 6 corresponds to the shape of the outer surface of the inclined sleeve 19, the outer ring of the sleeve ring 6 is arranged in the bearing seat 2 in a sliding manner, the cover plate is fixedly arranged on two sides of the bearing seat 2, the cover plate is matched with the step shaft 3 and used for axially fixing the inner ring of the bearing 1, the cover plate is also used for abutting against the outer ring, the pre-tightening mechanism is arranged on the cover plate close to one end, with the larger size, of the outer side of the inclined sleeve 19. The cover plate is fixed to the bearing block 2 by screws 17. The cover plate is divided into a front cover plate 5 and a rear cover plate 4, the front cover plate 5 is located at one end, with the larger size, of the outer side of the inclined sleeve 19, the pre-tightening mechanism is arranged on the front cover plate 5, a first bulge 7 and a second bulge 8 are arranged on the rear cover plate 4, the first bulge 7 is used for abutting against the inner ring of the bearing 1, and the second bulge 8 is used for abutting against the outer ring of the bearing 1.

A first gasket 9 is arranged between the front cover plate 5 and the inclined sleeve 19, and a second gasket 10 is arranged between the rear cover plate 4 and the bearing seat 2.

The pre-tightening mechanism comprises a motor 11, a driving gear 12, driven gears 20 and screws 16, the motor 11 is installed on the front cover plate 5, the driving gear 12 is fixed on a motor shaft of the motor 11, two sides of the driving gear 12 are meshed with the driven gears 20, the driven gears 20 are respectively fixedly connected with the two screws 16, the two screws 16 are rotatably arranged on the front cover plate 5, nuts 13 are connected to the two screws 16, the two nuts 13 are fixedly connected with the screw 16 through connecting rods 15, springs 14 are sleeved on the screws 16, the lengths of the screws 16 are smaller than the lengths of the springs 14 in a natural state, one ends of the springs 14 abut against the nuts 13, the other ends of the springs abut against the outer ring of the bearing 1, and sensors for detecting the stretching amount of the springs 14 are further arranged on the nuts 13. The number of the pre-tightening mechanisms is two, and the two pre-tightening mechanisms are symmetrically arranged around the axis of the bearing seat 2. The motor 11 is arranged on one surface, far away from the bearing 1, of the front cover plate 5, and a motor shaft of the motor 11 penetrates through the cover plate to be fixedly connected with the driving gear 12.

The working principle is as follows: an inner ring of a bearing 1 is installed with a step shaft 3, an inner ring at one side of the bearing 1 props against a step 18 of the step shaft 3, then an outer ring of the bearing 1 is installed with an inner ring of an inclined sleeve 19 in a matching way, the bearing 1 and the inclined sleeve 19 are installed in an interference way, when a pre-tightening mechanism pushes the outer ring of the bearing 1, the bearing 1 can drive the inclined sleeve 19 to move together, the outer surface of the inclined sleeve 19 is conical, one end of the inclined sleeve 19 with larger outer surface size is arranged close to the step 18 of the step shaft 3, the outer surface of the inclined sleeve 19 is installed with a lantern ring 6 in a matching way, the shape of the inner ring of the lantern ring 6 is consistent with that of the inclined sleeve 19, the lantern ring 6 is arranged in a sliding way in a bearing seat 2, cover plates are arranged at two sides of the bearing seat 2, a first bulge 7 of a rear cover plate 4 is matched with the step 18 of the step shaft 3 to prop against the inner ring, the front cover plate 5 is provided with a pre-tightening mechanism, one end of a spring 14 on a screw 16 of the pre-tightening mechanism is propped against the nut 13, the other end is propped against the outer ring of the bearing 1, and the front cover plate 5 is fixed on the bearing seat 2 through a screw 17. Starting a motor 11, wherein the motor 11 drives a driving gear 12 to rotate, the driving gear 12 drives a driven gear 20 which is rotatably arranged on a front cover plate 5 to rotate, nuts 13 on the driven gears 20 on two sides of the driving gear 12 are mutually limited, so that the nuts 13 can only do linear motion, the nuts 13 extrude a spring 14, the spring 14 pushes an outer ring of a bearing 1 to move towards a rear cover plate 4, the bearing 1 is in interference fit with an inclined sleeve 19, the inclined sleeve 19 is driven by the bearing 1 to move towards the rear cover plate 4, the inclined sleeve 19 and an inner ring of a lantern ring 6 are installed in a matched manner through an inclined surface, the lantern ring 6 is arranged in a bearing seat 2, the bearing seat 2 limits the lantern ring 6 to move towards a direction away from the bearing 1, so that the lantern ring 6 can only apply a radial force to the inclined sleeve 19, and the inclined sleeve 19 applies; meanwhile, the spring 14 of the pre-tightening mechanism pushes the outer ring of the bearing 1 to move towards the direction of the rear cover plate 4, the bearing 1 is axially adjusted, the stretching amount of the spring 14 is displayed on the sensor, and the pre-tightening force axially applied to the bearing 1 can be calculated through Hooke's law.

Example two

The only difference from the above embodiment is that: the cover plate is divided into a front cover plate 5 and a rear cover plate 4, the front cover plate 5 is located at one end, with the larger size, of the outer side of the inclined sleeve 19, the pre-tightening mechanism is arranged on the front cover plate 5, a first bulge 7 used for abutting against an inner ring of the bearing 1 is further arranged on the front cover plate 5, and a second bulge 8 used for abutting against an outer ring of the bearing 1 is arranged on the rear cover plate 4. The rear cover plate 4 is close to one end, with a smaller outer surface size, of the inclined sleeve 19, the second protrusion 8 is arranged on the rear cover plate 4 and used for abutting against an outer ring of the bearing 1, the first protrusion 7 is arranged on the front cover plate 5 and used for abutting against an inner ring of the bearing 1, the step 18 of the step shaft 3 is arranged close to the rear cover plate 4, and the step 18 of the step shaft 3 is matched with the first protrusion 7 to fix the inner ring of the bearing 1.

Claims

1. A bearing preloading device is characterized in that: the bearing comprises a bearing (1), a bearing seat (2), an inclined sleeve (19), a sleeve ring (6), a step shaft (3) and a cover plate, wherein the inner ring of the bearing (1) is installed in a matched mode with the step shaft (3), the outer ring of the bearing (1) is installed in an interference fit mode with the inner ring of the inclined sleeve (19), the outer side of the inclined sleeve (19) is installed in a matched mode with the inner ring of the sleeve ring (6), the outer surface of the inclined sleeve (19) is conical, the shape of the inner ring of the sleeve ring (6) is corresponding to the shape of the outer surface of the inclined sleeve (19), the outer ring of the sleeve ring (6) is arranged in the bearing seat (2) in a sliding mode, the cover plate is fixedly arranged on two sides of the bearing seat (2), the cover plate is matched with the step shaft (3) and used for axially fixing the inner ring of the bearing (1), and the cover plate is also used for abutting against, the bearing device is characterized by further comprising a pre-tightening mechanism for pushing the outer ring of the bearing (1) to move axially, wherein the pre-tightening mechanism is arranged on the cover plate close to one end, with the larger size, of the outer side of the inclined sleeve (19).

2. A bearing pretensioning device according to claim 1, characterized in that: the cover plate is divided into a front cover plate (5) and a rear cover plate (4), the front cover plate (5) is located at one end, with the outer side of the inclined sleeve (19), of the large size, the pre-tightening mechanism is arranged on the front cover plate (5), a first bulge (7) and a second bulge (8) are arranged on the rear cover plate (4), the first bulge (7) is used for abutting against the inner ring of the bearing (1), and the second bulge (8) is used for abutting against the outer ring of the bearing (1).

3. A bearing pretensioning device according to claim 1, characterized in that: the cover plate is divided into a front cover plate (5) and a rear cover plate (4), the front cover plate (5) is located at one end, with the size being larger, of the outer side of the inclined sleeve (19), the pre-tightening mechanism is arranged on the front cover plate (5), a first protrusion (7) used for abutting against an inner ring of the bearing (1) is further arranged on the front cover plate (5), and a second protrusion (8) used for abutting against an outer ring of the bearing (1) is arranged on the rear cover plate (4).

4. A bearing pretensioning device according to claim 2 or 3, characterized in that: a first gasket (9) is arranged between the front cover plate (5) and the inclined sleeve (19), and a second gasket (10) is arranged between the rear cover plate (4) and the bearing seat (2).

5. A bearing pretensioning device according to claim 1, characterized in that: the pre-tightening mechanism comprises a motor (11), a driving gear (12), driven gears (20) and screw rods (16), the motor (11) is installed on the front cover plate (5), the driving gear (12) is fixed on a motor shaft of the motor (11), two sides of the driving gear (12) are meshed with the driven gears (20), the two driven gears (20) are fixedly connected with the two screw rods (16) respectively, the two screw rods (16) are rotatably arranged on the front cover plate (5), the two screw rods (16) are connected with nuts (13), the two nuts (13) are fixedly connected through connecting rods (15), the screw rods (16) are sleeved with springs (14), the length of the screw rods (16) is smaller than that of the springs (14) in a natural state, one ends of the springs (14) abut against the nuts (13), the other end of the nut is propped against the outer ring of the bearing (1), and a sensor for detecting the expansion amount of the spring (14) is further arranged on the nut (13).

6. A bearing pretensioning device according to claim 5, characterized in that: the number of the pre-tightening mechanisms is two, and the two pre-tightening mechanisms are symmetrically arranged around the axis of the bearing seat (2).

7. A bearing pretensioning device according to claim 5, characterized in that: the motor (11) is arranged on one surface, far away from the bearing (1), of the front cover plate (5), and a motor shaft of the motor (11) penetrates through the cover plate and is fixedly connected with the driving gear (12).

8. A bearing pretensioning device according to claim 1, characterized in that: the cover plate is fixed on the bearing seat (2) through a screw (17).