JPH10313548A - Method for regulating axial gap of rotary shaft of rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily regulate an axial gap from outside a rotary electric machine with a low cost, by clamping a plurality of adjusting screws and a lock nut or thread-lock concentrically with a central axis of a rotary electric machine, and clamping bearings in an axial direction. SOLUTION: A plurality of (four) adjusting screws 20 are engaged with a cover 3 at a position on a circumference concentric with a central axis X-X of the rotary electric machine, ends are brought into contact with an outer face a of a rolling bearing 7, and fixed by a lock nut 21. Here, it may be fixed by a thread-lock such as adhesive instead of the nut 21. Thus, a rotary shaft 6 of the rotary electric machine is urged to one direction of an axial direction via an outer race 7a of the bearing 7 so that an axial gap 8 becomes invariable. Accordingly, number of components is little. The gap can be regulated with the components of low cost, and the gap can be regulated from an exterior after assembling.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to a rotating electric machine, and more particularly to a method for adjusting an axial gap generated in a rotating shaft of a rotating electric machine by accumulating manufacturing tolerances of related members in an assembled state.

[0002]

2. Description of the Related Art As shown in FIG. 3, a rotary electric machine generally comprises a frame 1, covers 2 and 3, a rotor 4, a stator 5, a rotary shaft 6, a rolling bearing 7, and the like. In the state where these related members are assembled, the tolerances permitted for the respective related members are often accumulated as a whole, so that an axial gap in the thrust direction is generated on the rotating shaft 6 of the rotating electrical machine. Inevitable. When a blade or the like for cutting a work material such as a brake or metal is attached to the rotating electric machine where the axial gap is generated in this way, the brake cap changes for the brake and the blade for the blade It is desirable to adjust the axial gap generated in this way to a minimum, since such movement causes adverse effects such as deformation of the cut. For this reason, various measures have conventionally been taken.

[0003]

Problems to be Solved by the Invention (1) As a first countermeasure of the related art, as shown in FIG. 4 (A) which is an enlarged detailed view of a portion C in FIG. 3, the rolling bearing is provided radially outward. A cover 11 for fixing in the axial direction is attached to the cover 3 provided, and a bearing nut 12 is attached to the rotating shaft 6. However, this method has the following disadvantages. 1) High cost. 2) Not suitable for small diameter shafts. 3) Backlash as an axial clearance of the bearing alone cannot be prevented. (2) The second conventional measure is as shown in FIG.
This is a method using 13 retaining rings for holes and 14 retaining rings for shafts. 1) Axial gaps such as the intersection of the positions and widths of the retaining ring grooves 15 and 16 and the intersection of backlash and width of the rolling bearing 7. And 2) the strength of the rotating shaft 6 is reduced due to the groove 16. (3) As a third measure of the related art, as shown in FIG. 4C, a wave ring, a disc spring, or a shim liner 1 is inserted into the axial gap 17.
8) 1) In the case of a wavy ring or disc spring, if an axial load exceeding a certain load is applied, the shaft will bend and the rotating shaft 6 will move. 2) Adjustment by the shim liner takes time and effort. There are drawbacks such as the inability to adjust the axial gap less than the shim thickness, and improvements have been demanded. Therefore, it is an object of the present invention to solve the above-mentioned drawbacks and to provide a low-cost method for easily adjusting the axial gap from outside the rotating electric machine.

[0004]

According to the present invention, (1) a plurality of adjusting screws and a lock nut (or a screw lock) are mounted on the cover of the rotating electric machine concentrically with the center axis of the rotating electric machine, and the bearing is mounted. (2) One adjusting screw and a lock nut (or a screw lock) are mounted on the central axis of the rotating electric machine, and the bearing is fixed via a countersunk plate. The above-described means (1) or (2) solves the problem by making it possible to adjust the axial clearance of the rotating shaft of the rotating electric machine.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a first embodiment of a method for adjusting an axial clearance of a rotating shaft of a rotating electric machine according to the present invention. FIG. 1A is an enlarged detailed view of a portion corresponding to a portion C in FIG. 3, and FIG. 1B is a view taken in the direction of arrow C in FIG. 1A. At a position on the circumference concentric with the central axis XX of the rotating electric machine, a plurality of, in this embodiment, four
, And each end is brought into contact with the outer ring 7 a of the rolling bearing 7 and fixed with the lock nut 21. Instead of the lock nut, it may be fixed with a screw lock such as an adhesive.

FIG. 2 shows a second embodiment of the present invention. FIG. 2 (A) is an enlarged detailed view of a portion corresponding to a portion D in FIG. 3, and FIG. It is an arrow view of the D section of (A). 2A, the adjusting screw 22 is screwed into the cover 2 on the central axis XX of the rotating electric machine, and the flange 24a of the dish-shaped abutment plate 24 having the flange 24a on the outer periphery is brought into contact with the outer ring 7a of the rolling bearing 7. The center is pressed with the adjusting screw 22 and fixed with the lock nut 23. The use of a screw lock instead of the lock nut is the same as in the first embodiment. In both the first and second embodiments, the axial gap 8 can be kept unchanged by pushing the rotating shaft 6 of the rotating electrical machine in the axial direction via the outer ring 7a of the rolling bearing.

[0007]

According to the present invention, the following effects can be obtained. (1) The gap can be adjusted with a small number of parts and inexpensive parts. (2) The gap can be adjusted from the outside after assembly. (3) Even if the gap becomes large due to driving, it can be easily adjusted on site. (4) Fine adjustment can be easily performed. (5) The dimensional accuracy in the axial direction of each component of the rotating electric machine need not be high. (6) By inserting an elastic body between the adjusting screw and the bearing, a structure that absorbs expansion due to heat generation can be easily manufactured. (7) It is also possible to adjust the gap of the steel plate type rotary electric machine that fixes the frame and the cover by non-decomposable caulking.

[Brief description of the drawings]

FIG. 1A shows a first embodiment of a method for adjusting an axial clearance of a rotating shaft of a rotating electric machine according to the present invention;
FIG. 1B is an enlarged detailed view of a portion corresponding to a portion C in FIG.
FIG. 2 is a view as seen from the arrow C in FIG.

FIG. 2A is an enlarged detailed view of a portion corresponding to a portion D in FIG. 3 showing the second embodiment, and FIG. 2B is a view taken in the direction of arrow D in FIG. It is.

FIG. 3 is a longitudinal sectional view showing a structure of a general rotating electric machine.

4 (A), 4 (B) and 4 (C) each show a method of adjusting an axial clearance of a rotating shaft of a conventional rotary electric machine, and a portion corresponding to a portion C in FIG. 3; FIGS. 4A and 4B are first, second, and third examples of the enlarged detailed view of FIG.

[Explanation of symbols]

 1: Frame 2: 3: Cover 4: Rotor 5: Stator 6: Rotating shaft 7: Rolling bearing 7a: Outer ring 8: Axial clearance 20, 22: Adjusting screw 21, 23: Lock nut 24: Countersunk plate 24a: Flange

Claims (2)

[Claims] 1. A rotating shaft (6), a rotor (4) mounted on an outer periphery of the rotating shaft (6), and the rotating shaft (6).
Rolling bearings (7) provided on the outer periphery on both the left and right sides in the axial direction of the vehicle, a cover (3) fitted to the outer ring (7a) of these rolling bearings (7), and a radius of the cover (3) And a frame (1) on the inner periphery of which a rotor (4) and a stator (5) opposed to the rotor (4) are arranged, and assembling related members of the rotating electric machine. In this case, as a method of adjusting the axial clearance of the rotating shaft by accumulating the manufacturing tolerances of these members, a plurality of adjusting screws (20) are screwed from one outside of the cover (3) to the threaded portions at the respective ends. Are screwed into contact with the side surface of the outer ring (7a) of the rolling bearing (7), and each of these adjusting screws (20) is adjusted so as to be in close contact with the side surface of the outer ring (7a) of the rolling bearing (7). And lock nuts Method of adjusting the axial clearance of the rotary shaft of the rotary electric machine, characterized in that to secure the adjusted position by fixing method Flip. 2. A plate-shaped abutment plate (24) having an annular flange (24a) on its outer periphery is brought into contact with the flange (24a) surface against the outer surface of an outer ring (7a) of the rolling bearing (7). The plate-shaped abutment plate (24) is pressed from the outside of the one cover (2) on the axis of the rotating electric machine by an adjustment screw (22), and the adjustment position is fixed by a screw fixing method such as a lock nut (23). 2. The method for adjusting an axial gap of a rotating shaft of a rotating electric machine according to claim 1, wherein: