Axial anti-walk structure of an alternating current motor

Abstract

The utility model discloses an axial anti -runout structure of alternating -current motor, including stator subassembly, rotor subassembly, casing, front end cover, rear end cover and motor shaft, the rear end cover top is equipped with the window of the cable line and is worn into, and the rear end cover middle part is equipped with a boss, and the boss middle part is equipped with a blind hole for installing the bearing, and the rear axle end of motor shaft is worn into the bearing inner ring, and the rear axle end of motor shaft and bearing inner ring interference fit, and bearing outer ring and blind hole clearance fit, still include screw and the elastic sheet of cross section is U shape by the elastic material, and the boss is equipped with the screw hole of parallel arrangement with motor shaft, and the screw rod of screw passes through elastic sheet and is screwed into screw hole, and the distance between the nail head bottom surface of screw and boss top surface and elastic sheet thickness are adapted, and elastic sheet inserts and installs between the nail head bottom surface of screw and boss top surface, and elastic sheet lower extreme and bearing outer ring are in contact. The utility model effectively prevented motor shaft axial runout, and elastic sheet installation and replacement are convenient, quick.

Description

Technical Field

[0001] This utility model relates to an AC motor, and more particularly to an axial anti-movement structure for the motor shaft of an AC motor, belonging to the field of motor technology. Background Technology

[0002] The existing axial anti-running structure for AC motors includes a stator assembly, a rotor assembly, a housing, a front cover, a rear cover, and a motor shaft. The stator assembly is mounted on the housing, the rotor assembly is mounted on the motor shaft, the front cover is mounted on the front face of the housing, and the rear cover is mounted on the rear face of the housing. The rear cover has a boss in the center, with a blind hole for mounting a bearing in the center of the boss. The rear end of the motor shaft passes through the inner ring of the bearing, with an interference fit between the rear end of the motor shaft and the inner ring. The outer ring of the bearing has a clearance fit with the blind hole. A corrugated shim is placed at the bottom of the blind hole, and the bearing abuts against the corrugated shim. The alternating arrangement of the crests and troughs of the corrugated shim generates a uniform elastic force under pressure. The axial preload provided by this elastic force prevents axial runout of the motor shaft.

[0003] However, this AC motor axial anti-running structure has the following four defects during use: (1) The axial preload provided by the elastic force generated by the wave gasket when it is compressed is used to prevent the motor shaft from running axially. However, after the wave gasket has been subjected to alternating load for a long time, it is easy to undergo plastic deformation. After plastic deformation, the elasticity of the wave gasket decreases, stress relaxation occurs, the preload is gradually lost, or even completely lost, and finally it cannot prevent the axial running of the motor shaft; (2) Under high frequency vibration environment, the wave gasket is prone to fatigue cracks or even breakage, which affects the reliability of the motor; (3) When the wave gasket is damaged and needs to be replaced, the motor needs to be disassembled before it can be replaced, which is very inconvenient; (4) During installation, grease needs to be used to stick the wave gasket to the bottom of the blind hole, which is inconvenient. Summary of the Invention

[0004] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide an AC motor axial anti-movement structure that can effectively prevent axial movement of the motor shaft, enable quick installation and replacement, ensure smooth and reliable motor operation, and has a simple structure.

[0005] To solve the above-mentioned technical problems, this utility model adopts an axial anti-running structure for an AC motor, including a stator assembly, a rotor assembly, a housing, a front end cover, a rear end cover, and a motor shaft. The stator assembly is mounted on the housing, the rotor assembly is mounted on the motor shaft, the front end cover is mounted on the front end face of the housing, and the rear end cover is mounted on the rear end face of the housing. The top of the rear end cover has a window for cable insertion, and the center of the rear end cover has a boss with a blind hole for mounting a bearing. The motor shaft... The rear end of the motor shaft passes through the inner ring of the bearing, and the rear end of the motor shaft is interference-fitted with the inner ring of the bearing. The outer ring of the bearing is clearance-fitted with the blind hole. The motor shaft also includes a screw and an elastic plate with a U-shaped cross-section made of elastic material. The boss has a screw hole arranged parallel to the motor shaft. The screw shank passes through the elastic plate and is screwed into the screw hole. The distance between the bottom surface of the screw head and the top surface of the boss is adapted to the thickness of the elastic plate. The elastic plate is inserted between the bottom surface of the screw head and the top surface of the boss, and the lower end of the elastic plate abuts against the outer ring of the bearing.

[0006] In a preferred embodiment of this utility model, the distance between the bottom surface of the screw head and the top surface of the boss is 0 to 0.05 mm greater than the thickness of the elastic sheet.

[0007] In a preferred embodiment of this utility model, the elastic sheet is made of stainless steel or spring steel and has a thickness of 1.5 to 3 mm.

[0008] By adopting the above structure, this utility model has the following beneficial effects:

[0009] This utility model includes a screw and an elastic sheet with a U-shaped cross-section made of elastic material. The boss has a screw hole, and the screw shank passes through the elastic sheet and is screwed into the screw hole. The distance between the bottom surface of the screw head and the top surface of the boss is adapted to the thickness of the elastic sheet. The elastic sheet is inserted between the bottom surface of the screw head and the top surface of the boss, and the lower end of the elastic sheet abuts against the outer ring of the bearing. This structure has several advantages. First, the lower end of the elastic plate abuts against the outer ring of the bearing, pressing and fixing the outer ring within the blind hole of the rear end cover. Because the outer ring is confined within the blind hole and cannot move axially, and because the rear end of the motor shaft is interference-fitted with the inner ring of the bearing, the motor shaft cannot move axially, effectively preventing axial movement. Second, installing the elastic plate does not require disassembling the motor; simply insert the elastic plate into the gap between the bottom surface of the nail head and the top surface of the boss through the window at the top of the rear end cover. When the elastic plate is damaged and needs replacement, it can be easily removed through the window at the top of the rear end cover, making installation and replacement convenient and quick. Third, the elastic plate is less prone to fatigue cracks or breakage under high-frequency vibration, better ensuring smooth and reliable motor operation.

[0010] This utility model has a simple structure, is easy to implement, and is convenient to promote and apply. Attached Figure Description

[0011] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings.

[0012] Figure 1 This is a schematic diagram of an AC motor axial anti-movement structure according to the present invention.

[0013] Figure 2 for Figure 1 A side view diagram.

[0014] Figure 3 for Figure 2 A cross-sectional view along line A-A.

[0015] Figure 4 for Figure 3 A magnified view of a portion of point B in the middle.

[0016] Figure 5 This is a schematic diagram of one structure of the elastic sheet in this utility model. Detailed Implementation

[0017] See Figures 1 to 5 The diagram illustrates an axial anti-slip structure for an AC motor, comprising a stator assembly 1, a rotor assembly 2, a housing 3, a front end cover 4, a rear end cover 5, and a motor shaft 6. The stator assembly 1 is fixedly mounted on the housing 3 via a mounting plate. The rotor assembly 2 is mounted on the motor shaft 6 via a key block. The front end cover 4 is bolted to the front face of the housing 3, and the rear end cover 5 is bolted to the rear face of the housing 3. The rear end cover 5 has a window 5-1 at its top for cable insertion. A boss 5-2, preferably a truncated cone, is located in the middle of the rear end cover 5. A blind hole 5a for mounting a bearing 7 is located in the middle of the boss 5-2. The rear end of the motor shaft 6 passes through the inner ring of the bearing 7, and the motor shaft... The rear end of the motor shaft 6 is interference-fitted with the inner ring of the bearing 7, and the outer ring of the bearing 7 is clearance-fitted with the blind hole 5a. The assembly also includes a screw 8 and a U-shaped elastic sheet 9 made of elastic material, preferably a metal elastic sheet. The boss 5-2 has a screw hole 5b arranged parallel to the motor shaft 6, preferably located on the upper part of the boss 5-2. The screw 8 passes through the opening of the elastic sheet 9 and is screwed into, preferably tightened, the screw hole 5b. The distance L between the bottom surface of the screw head and the top surface 5c of the boss 5-2 is adapted to the thickness of the elastic sheet 9. The elastic sheet 9 is inserted between the bottom surface of the screw head and the top surface 5c of the boss 5-2, and the lower end 9-1 of the elastic sheet 9 abuts against the outer ring of the bearing 7.

[0018] In a preferred embodiment of this utility model, the distance L between the bottom surface of the screw head of the screw 8 and the top surface 5c of the boss 5-2 is 0 to 0.05 mm greater than the thickness of the elastic sheet 9.

[0019] In a preferred embodiment of this utility model, the elastic sheet 9 is made of materials such as stainless steel or spring steel, and has a thickness of 1.5 to 3 mm.

[0020] When installing the elastic sheet 9, this utility model only requires inserting the elastic sheet 9 into the gap between the bottom surface of the nail head and the top surface of the boss 5c from the window 5-1 at the top of the rear end cover 5; when the elastic sheet 9 is damaged and needs to be replaced, it can also be removed from the window 5-1 at the top of the rear end cover 5. The installation and replacement of the elastic sheet 9 are convenient and quick.

[0021] After trial use, this utility model has a simple structure, effectively prevents axial movement of the motor shaft, and the elastic sheet is easy and quick to install and replace, achieving good practical results.

Claims

1. An axial anti-running structure for an AC motor, comprising a stator assembly (1), a rotor assembly (2), a housing (3), a front end cover (4), a rear end cover (5), and a motor shaft (6), wherein the stator assembly (1) is mounted on the housing (3), the rotor assembly (2) is mounted on the motor shaft (6), the front end cover (4) is mounted on the front end face of the housing (3), and the rear end cover (5) is mounted on the rear end face of the housing (3). The top of the rear end cover (5) is provided with a window (5-1) for a cable to pass through, and a boss (5-2) is provided in the middle of the rear end cover (5). The boss (5-2) is provided with a blind hole (5a) for mounting a bearing (7) in the middle. The rear end of the motor shaft (6) passes through the inner ring of the bearing (7), and the rear end of the motor shaft (6) is interference-fitted with the inner ring of the bearing (7). The outer ring of the bearing (7) is clearance-fitted with the blind hole (5a). It also includes a screw (8) and an elastic plate (9) with a U-shaped cross section made of elastic material. The boss (5-2) is provided with a screw hole (5b) arranged parallel to the motor shaft (6). The screw (8) passes through the elastic plate (9) and is screwed into the screw hole (5b). The distance (L) between the bottom surface of the screw head and the top surface (5c) of the boss (5-2) is adapted to the thickness of the elastic plate (9). The elastic plate (9) is inserted between the bottom surface of the screw head and the top surface (5c) of the boss (5-2). The lower end (9-1) of the elastic plate (9) abuts against the outer ring of the bearing (7).

2. The axial anti-walk structure for an alternating current motor as set forth in claim 1, characterized in that: The distance (L) between the bottom surface of the screw head and the top surface (5c) of the boss (5-2) is 0 to 0.05 mm greater than the thickness of the elastic sheet (9).

3. An axial anti-rotation structure for an alternating current motor as set forth in either of claims 1 or 2, characterized by: The elastic sheet (9) is made of stainless steel or spring steel and has a thickness of 1.5 to 3 mm.

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