JPS6130427Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of an electric motor with a brake device, in which a friction plate is moved in the axial direction of the rotor by magnetic attraction force during operation of the electric motor to release the braking action.

The first electric motor with a brake device as described above
What is shown in the figure is provided.

That is, the rotor 1 and the pull rotor 3 are integrated and fixed to the rotor shaft 4, and the pull rotor 3 is located at the front of the stator 2 (on the left in the figure), and the pull rotor 3 is located at the rear of the stator 2 (on the right in the figure). The rotor 1 is positioned, and the attracted object 9 made of a magnetic material provided as a boss part of the brake disc 5 is spline-fitted 7 to the rotor shaft 4 facing the front surface of the pull rotor 3, and the attracted object 9 and the rotor 1 are connected to each other by spline fitting 7. Coil spring 8 compressed between
The friction plate 10 provided on the front peripheral surface of the brake disc 5 is pressed against the fixed surface 6 by the elastic force of the brake disc 5 to perform a braking action. A retaining nut b is screwed onto a male threaded portion a of an outer end 4' which is pivotally supported by a bearing 13 and protrudes outward (to the left in the figure) of the ball bearing 13. By the way, in this type of electric motor with a brake device, when the electric motor is operated, the attracted object 9 is pulled inward (to the right in the figure) by the magnetic attraction force of the pull rotor 3 against the elastic force of the coil spring 8. As a result, the gap s between the pull rotor 3 and the attracted object 9 (usually about 0.5 mm is optimal) becomes 0, and the braking action of the brake disc 5 is released. Since the rotor 1 is unevenly distributed toward the rear, the stator 2 exerts an outward thrust A on the rotor 1.
is activated, and the friction plate 10 occasionally moves very slightly outward together with the brake disc 5, and the friction plate 10 comes into contact with the fixed surface 6 with light pressure. In this case, the friction plate 10 wears out unnecessarily and earlier than the predetermined service life, and therefore the maintenance and inspection period for maintaining the distance between the gaps s is shortened. It is an object of the present invention to provide an electric motor with a brake device that does not have such drawbacks and allows the adjustment of the gap s to be extremely easy.

An embodiment of the present invention will be described in detail below with reference to FIG. Hereinafter, the same numbers as in FIG. 1 indicate similar members. In this embodiment, reference numeral 14 is a cylindrical body with a flange, which has a flange C at the inner end and has a female threaded part d and a male threaded part e carved on the inner and outer cylindrical surfaces of the outer end. The outer end 4' of the ball bearing 13 is inserted and the male threaded part f of the outer end is screwed into the female threaded part d, and the inner end surface of the inner ring g of the ball bearing 13 is brought into contact with the collar c on the outside of the cylinder 14. Let me ball bearing 13
is fitted, and the lock washer 15 is first fitted to the externally protruding male threaded part e of the ball bearing 13 in such a manner that it is locked in the vertical groove i, and the lock nut 16 is screwed and tightened. , and the outer circumferential protrusion of the washer 15 is bent into the outer circumferential recess of the nut 16, and the flanged cylinder 14 and the ball bearing 1 are bent.
3 is fixed. The outer ring h of the bearing 13 is fixed to the inward cylindrical body 12' of the cover 12 screwed into the open part of the housing 11. Reference numeral 17 denotes a detent that is fitted onto the outer end of the externally threaded portion f of the rotor shaft 4 protruding outward from the flanged cylinder 14 in a locked state in the vertical groove i, so that the outer peripheral projecting piece is bent into the vertical groove i. Fit the two disc springs 18 on the outside with washers, then screw and tighten the lock nut 20 via the non-rotation washer 19, and tighten the outer circumferential protrusion of the washer 19 to the nut 20.
Bend it to the outer circumferential recess. When fixing the rotor shaft 4 and the flanged cylinder 14, first, finely adjust the threading depth of the male threaded part f of the rotor shaft 4 into the female threaded part d of the cylinder 14, and then tighten the pull rotor 3 on the rotor shaft 4. Move it so that the gap s with the object to be attracted 9 is about 0.5 mm.

In this way, when the electric motor is energized, the object 9 to be attracted is pulled toward the pull rotor 3 against the elasticity of the spring 8, and the distance of the gap s becomes 0, and the friction plate 10
is separated from the fixed surface 6, the braking action of the brake device is released, and the rotor shaft 1 rotates. When the electricity is turned off, the attracted body 9 returns to its original position by the elasticity of the spring 8, and the friction plate 10 of the brake device comes into contact with the fixed surface 6 again, receiving a braking action and causing the rotor shaft 4 to stop suddenly.

The present invention is as described above, and the rotor shaft 4,
The flanged cylinder 14, the bearing 13, and the cover 12 are fixed to each other in sequence, and the rotor shaft 4 cannot be completely moved in the axial direction. The rotor 1 moves in response to the thrust A, and a chain block connected to the rotor shaft 4 mechanically exerts a large thrust A to move the rotor 1, which also pushes the brake disc 5 and causes friction. This prevents the plate 10 from unnecessarily contacting the fixing surface 6 and causing premature wear. Conventionally, as a means to prevent this drawback, floating springs have been used to push the friction plates inward to counteract the movement caused by thrust A, but since the springs are used, the pressing force decreases due to material fatigue, and the elastic modulus of the springs decreases. It has poor performance due to variations in the pressure force, etc., and the elasticity of the floating spring must be used against the pressure force of the friction plate, which may interfere with the original braking action. However, the present invention does not have the above drawbacks because the lateral movement of the rotor shaft is fixed as described above. Of course, in order to fix the rotor shaft to the bearing, it is also possible to provide a male thread on the rotor shaft 4 inside the bearing 13 in FIG. 1 and screw a lock nut into this, but in this case, In order to obtain an appropriate gap S, it is difficult to tighten the nut between the brake disc and the bearing, which is difficult to do.However, with the present invention, this does not occur, and when the lock nut 20 is heated, , bearing 1
This is extremely convenient because the gap s can be adjusted by easily rotating the threaded cylindrical body 14 within the rotor shaft 3 with respect to the male threaded portion f at the outer end of the rotor shaft. Moreover, when the cylindrical body 14 moves forward and backward by screw rotation, the cylindrical body 14 rotates with respect to the rotor shaft 4 via the female threaded portion d, and the same cylindrical body 14 is rotatable with respect to the bearing 13. The inner ring g allows suitable rotation and facilitates adjustment work. In this way, the friction plates of the present invention do not wear out unnecessarily during operation, so there is less need to replace the friction plates, and the number of inspections for adjusting the gap is reduced, and the gap can be adjusted easily. It has the following characteristics.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of a conventional example, and FIG. 2 is a side sectional view of an embodiment of the present invention. In the figure, 1... rotor, 2... stator, 3...
Pull rotor, 4... Rotor shaft, 5... Brake disc, 6... Fixed surface, 7... Spline fitting, 8...
... Coil spring, 9 ... Attracted object, 10 ... Friction plate, 11 ... Housing, 12 ... Cover, 13
...Ball bearing, 14...Cylinder with flange, 1
6... Locknut, 20... Locknut.

Claims (1)

[Claims for Utility Model Registration] A cover 12 is attached to one open end of a housing 11, and a rotor shaft 4 is mounted inside the housing 11.
, a pull rotor 3 fixed to the rotor shaft 4, and an object 9 to be attracted which is spline-fitted to the rotor shaft 4 and can be freely attracted to the pull rotor 3 against the elasticity of the spring 8.
and a brake disc 5 fixed to the attracted object 9, and a bearing 13 is interposed between the cover 12 and the rotor shaft 4, the electric motor has a flange C at the inner end. A cylindrical body 1 with a flange, in which a female threaded part d and a male threaded part e are respectively carved on the inner and outer cylindrical surfaces of the outer end.
At the same time, a lock nut 16 is screwed into the male thread part e of the flanged cylinder 14, and the inner ring g of the bearing 13 is held between the collar C and the lock nut 16. On the other hand, the outer ring h of the bearing 13 is covered with a cover 1.
2, and a lock nut 20 is screwed onto a male threaded portion f of the outer end of the rotor shaft protruding from the outer end of the flanged cylinder 14.