CN116979741A - Motor bearing inner cover and motor - Google Patents

Abstract

The invention relates to a motor bearing inner cover and a motor, wherein the bearing inner cover comprises a disk body, a through hole is formed in the middle of the disk body, a plurality of bolt holes are formed in the edge of the disk body along the circumferential direction, an annular boss is arranged on one side of the disk body along the outer circumference of the through hole, the outer surface of the boss is parallel to the outer surface of the same side of the disk body, the outer surface of the boss protrudes out of the outer surface of the same side of the disk body, one end, close to the through hole, of the boss is connected with the disk body into a whole, and one end, far away from the through hole, of the boss is suspended and an open groove is formed between the boss and the outer surface of the same side of the disk body. The bearing inner cover designed by the invention can ensure that the bearing inner cover is always in surface contact with the bearing after the bolt pretightening force is applied, so that the problem of stress concentration in the prior art is avoided, the service life of materials is effectively prolonged, and the reliability of the motor is improved.

Description

A kind of motor bearing inner cover and motor

Technical field

The invention relates to the field of motor technology, and in particular to a motor bearing inner cover and a motor.

Background technique

The bearing inner cover inside the motor is used to fix the bearing. In order to prevent the bearing from axial shaking, the bearing inner cover is usually equipped with a boss on the side facing the bearing. When installing, the outer surface of the boss must fit closely with the bearing. The edge is fixedly connected to the shell through bolts. Since the outer surface of the boss on the existing inner cover of the bearing and the fitting surface of the bearing are parallel to each other, when no pre-tightening force is applied to the bolts fixing the inner cover of the bearing, the contact surface between the outer surface of the boss on the inner cover of the bearing and the bearing is: Surface contact, after applying pre-tightening force to the bolts on the inner cover of the bearing, the outer surface of the boss of the inner cover of the bearing turns into line contact with the bearing, which will cause stress concentration in the line contact area and easily lead to the risk of material failure.

Contents of the invention

The present invention improves the existing bearing inner cover structure. Two different structural designs are given below, both of which avoid the problem of stress concentration in the contact area between the bearing inner cover and the bearing after the bolt pretightening force is applied.

In order to achieve the above objects, the technical solutions adopted by the present invention are:

An inner cover of a motor bearing includes a disk body. A through hole is provided in the middle of the disk body. A plurality of bolt holes are provided on the edge of the disk body along the circumferential direction. An annular boss is provided on one side of the disk body along the outer circumference of the through hole. The boss is The outer surface is parallel to the outer surface on the same side of the plate body, and the outer surface of the boss protrudes from the outer surface of the same side of the plate body; the end of the boss close to the through hole is integrated with the plate body, and the end of the boss away from the through hole is suspended and An open groove is formed between the outer surfaces on the same side as the plate body.

Further, the depth dimension of the open groove is set to A, the contact width dimension of the surface where the bearing fits the boss is set to D, and A is 40% to 60% of D.

Further, the A is 50% of D.

Further, the height dimension of the boss is set to C, the width dimension of the open groove is set to B, and B is 25% to 50% of C.

Further, said C≥4mm.

Further, the B is 1 mm to 5 mm.

The invention also discloses a motor, which includes a housing, a bearing and the above-mentioned bearing inner cover. The outer surface of the boss of the bearing inner cover fits the bearing, and the bearing inner cover is fixedly connected to the housing through bolts.

An inner cover of a motor bearing includes a disk body. A through hole is provided in the middle of the disk body. A plurality of bolt holes are provided on the edge of the disk body along the circumferential direction. An annular boss is provided on one side of the disk body along the outer circumference of the through hole. The boss is The outer surface protrudes from the outer surface on the same side of the plate body, and the outer surface of the boss is inclined relative to the outer surface on the same side of the plate body, with the inclination direction facing the edge of the plate body.

The invention also discloses a motor, which includes a housing, a bearing and the above-mentioned bearing inner cover with an inclined surface boss. The inclined surface of the boss of the bearing inner cover fits the bearing. The bearing inner cover is fixedly connected to the housing through bolts.

The bearing inner cover designed by the present invention can ensure that the bearing inner cover and the bearing are always in surface contact after applying bolt pre-tightening force, avoiding the problem of stress concentration in the prior art, effectively extending the service life of the material, and improving the efficiency of the motor. reliability.

Description of the drawings

Figure 1 is a schematic structural diagram of the bearing inner cover facing the outside of the motor in Embodiment 1;

Figure 2 is a schematic structural diagram of the bearing inner cover facing the inside of the motor in Embodiment 1;

Figure 3 is a longitudinal cross-sectional view of the bearing inner cover in Embodiment 1;

Figure 4 is a partial enlarged view of the cross-sectional view in Figure 3;

Figure 5 is a partial assembly diagram of the bearing inner cover on the motor in Embodiment 1;

Figure 6 is a diagram showing the design dimensions of the bearing inner cover and the bearing in the first embodiment;

Figure 7 is a longitudinal partial cross-sectional view of the bearing inner cover in the second embodiment.

Explanation of reference symbols:

1. Disk body; 2. Boss; 3. Bolt hole; 4. Open groove; 5. Bearing inner cover; 6. Bearing; 7. Shell; 8. Bolt; 9. Inclined boss.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

Referring to Figures 1, 2 and 5, the motor bearing inner cover in the prior art includes a disk body 1. A through hole is provided in the middle of the disk body 1 for the rotating shaft to pass through. The edge of the disk body 1 is arranged along the circumferential direction. A plurality of bolt holes 3 are opened, and one side of the plate body 1 is provided with an annular boss 2 protruding from the outer surface of the same side of the plate body 1. The boss 2 is arranged along the outer circumference of the through hole. The side where the boss 2 is provided is the side where the inner cover of the bearing and the bearing 6 fit together. In the prior art, the outer surface of the boss 2 is usually made to be close to the bearing. Therefore, the boss on the inner cover of the bearing in the prior art The outer surfaces and the outer surfaces on the same side of the disk body 1 are parallel to each other. Since the inner cover of the bearing needs to be fixedly connected to the housing 7 through bolts 8, once the pre-tightening force is applied to bolt 8, the boss 2 of the inner cover of the bearing squeezes the side of the bearing 6, and the boss 2 of the inner cover of the bearing presses against the reaction force. The contact surface is tilted and deformed, causing the original surface contact between the bearing inner cover and the bearing 6 to evolve from a surface contact to a line contact. The stress is concentrated in the area where the bearing inner cover boss 2 has a line contact. Long-term use is likely to cause material failure, thereby affecting the reliability of the motor. .

This embodiment improves the design of the existing bearing inner cover structure mentioned above to solve the above problems. Two structural improvement schemes are given below.

Embodiment 1: In this embodiment, an open groove 4 is provided on the boss 2 of the inner cover of the bearing. As shown in Figure 3 and Figure 3, the end of the boss 2 close to the through hole is connected to the plate body 1 as a whole, and the boss 2 is integrated with the plate body 1. One end of the platform 2 away from the through hole is suspended in the air, and there is a gap between the suspended end and the outer surface of the same side of the plate body 1, and an open groove 4 is formed in the gap. Due to the existence of the open groove 4, when the bolt pre-tightening force is applied, the suspended end of the bearing inner cover boss 2 will deform and reserve elastic potential energy. Under the action of the elastic potential energy, the boss 2 will be squeezed toward the bearing 6 side. , so that the boss 2 and the side surface of the bearing 6 always maintain surface contact, thus avoiding the occurrence of stress concentration problems. In addition, during long-term use of the motor, the bolts are prone to fatigue and creep loosening. Especially once the bolts 8 fixing the inner cover of the bearing become loose, the axial shaking of the bearing 6 will increase, which will reduce the service life of the motor. In this embodiment, since the existence of the open groove 4 will reserve elastic potential energy, even if the bolt 8 becomes slightly loose, the inner cover of the bearing will release the elastic potential energy to always keep the bearing 6 in a fixed state, thus improving the reliability of the motor. sex.

Specifically, when designing the relevant dimensions of the open groove 4, refer to the dimension marking diagram shown in Figure 6, assuming that the depth dimension of the open groove 4 is A, and assuming that the bearing 6 fits the surface of the boss 2 The contact width dimension is D, the height dimension of the boss 2 is C, and the width dimension of the open groove 4 is B. It is appropriate to design dimension A to be 40% to 60% of dimension D, preferably A to be 50% of D. If the dimension A is too deep, although it fits the mating pair better, it will cause the suspended end of the boss 2 to be stressed too much and cause permanent deformation, losing the ability to rebound; if the dimension A is too shallow, it will lose its support. The ability to deform and fit paired pairs. For the design of dimension B, considering the processing capacity, it is appropriate to set B to be 25% to 50% of C. Especially for the case where the height of boss 2 is C≥4mm, B is preferably 1mm to 5mm.

The motor is assembled using the bearing inner cover given in the first embodiment, as shown in Figure 5. Figure 5 is a simplified partial assembly diagram. The rotating shaft is omitted in the figure, and only the bearing inner cover 5, bearing 6 and the upper part of the rotating shaft are shown. The half structure of the housing 7 fits the outer surface of the boss 2 of the bearing inner cover 5 to the side of the bearing 6. The bearing inner cover 5 is fixedly connected to the housing 7 after applying pre-tightening force through bolts 8.

Embodiment 2: The bearing inner cover in this embodiment is shown in Figure 7. The bearing inner cover in this embodiment is a bevel boss 9. The outer surface of the bevel boss 9 is not parallel to the outer surface of the disk body 1 on the same side. , but has a certain inclination relative to the outer surface on the same side of the disk body 1, and the inclination direction is toward the edge of the disk body 1, that is, the end of the inclined boss 9 close to the through hole is higher than the end away from the through hole. The plane where the outer surface of the inclined boss 9 is located and the plane where the outer surface of the disc body 1 is on the same side presents an inclined angle a. This included angle a mainly considers the thickness of the disc body 1, the magnitude of the pre-tightening force exerted by the bolt 8, the specific structure of the bearing inner cover, etc. Factors can be used to calculate the deformation of the bearing inner cover when it is locked with the help of finite elements, thereby determining the inclination angle to be processed. The design of the inclined boss 9 given in this embodiment can also avoid the stress concentration after the pre-tightening force is applied to the bolt 8. When no pre-tightening force is applied, the outer surface of the inclined boss 9 is in line contact with the side surface of the bearing 6. , but once the preload force is applied, it becomes surface contact, which is exactly opposite to the situation of the bearing inner cover in the prior art.

The bearing inner cover given in the second embodiment is used to assemble the motor. The inclined surface of the inclined boss 9 of the bearing inner cover is fitted to the bearing 6 . The bearing inner cover is fixedly connected to the housing 7 through bolts 8 .

Although two bearing inner covers with different structures are given above, the solution of the second embodiment requires higher processing accuracy of the inclination angle of the bevel boss 9, and the bearing inner cover in the second embodiment does not have elastic potential energy storage capacity. , once the bolt 8 becomes loose, the bearing inner cover cannot fully fix the bearing 6. The solution given in the first embodiment can reduce the machining accuracy requirements of the contact surface of the boss 2 of the bearing inner cover, and the deformation of the suspended end of the boss 2 can be used to make up for the lack of machining accuracy, and the first embodiment can appear on the bolt 8 In the case of slight looseness, the inner cover of the bearing is pressed tightly against the bearing 6 by the release of elastic potential energy, thereby preventing the bearing 6 from axial shaking.

Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art will understand that various changes, modifications, and substitutions can be made to these embodiments without departing from the principles and spirit of the invention. and modifications, the scope of the invention is defined by the appended claims and their equivalents.

Claims (9)

1. A motor bearing inner cover, characterized in that: it includes a disk body, a through hole is provided in the middle of the disk body, a plurality of bolt holes are provided on the edge of the disk body along the circumferential direction, and an annular shape is provided on one side of the disk body along the outer circumference of the through hole. Boss, the outer surface of the boss is parallel to the outer surface of the same side of the plate body, the outer surface of the boss protrudes from the outer surface of the same side of the plate body, the end of the boss close to the through hole is connected to the plate body, and the boss is far away One end of the through hole is suspended and an open groove is formed between the outer surface on the same side of the plate body. 2. A motor bearing inner cover according to claim 1, characterized in that: the depth dimension of the open groove is set to A, and the contact width dimension of the surface where the bearing fits the boss is set to D, and A is 40% to 60% of D. 3. A motor bearing inner cover according to claim 2, characterized in that: A is 50% of D. 4. A motor bearing inner cover according to claim 1, characterized in that: the height dimension of the boss is set to C, the width dimension of the open groove is set to B, and B is 25% to 50 of C. %. 5. A motor bearing inner cover according to claim 4, characterized in that: said C≥4mm. 6. A motor bearing inner cover according to claim 4, characterized in that: the B is 1 mm to 5 mm. 7. A motor, characterized in that it includes a housing, a bearing and an inner bearing cover as claimed in any one of claims 1 to 6. The outer surface of the boss of the inner bearing cover fits the bearing, and the inner cover of the bearing is connected to the bearing through bolts. The shell is fixedly connected. 8. A motor bearing inner cover, characterized in that: it includes a disk body, a through hole is provided in the middle of the disk body, a plurality of bolt holes are provided on the edge of the disk body along the circumferential direction, and an annular shape is provided on one side of the disk body along the outer circumference of the through hole. The outer surface of the boss protrudes from the outer surface of the same side of the plate body. The outer surface of the boss is inclined relative to the outer surface of the same side of the plate body, and the inclination direction is toward the edge of the plate body. 9. A motor, characterized in that it includes a housing, a bearing and an inner bearing cover as claimed in claim 8. The inclined surface of the boss of the inner cover of the bearing fits the bearing, and the inner cover of the bearing is fixedly connected to the housing through bolts. .