JPH0125303B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an electric chain block, an electric traveling device, or other mechanical equipment equipped with an attraction release type brake device configured to be automatically released by magnetic attraction force when an electric motor is operated. The invention relates to electric motors.

In such electric motors, each time the motor is started, the brake disc is suddenly attracted and collides with the suction body, resulting in a large impact force acting on the suction body, which can damage the components of the motor over long periods of use. Otherwise, the mounting parts of each part may become loose. In order to alleviate the impact force generated by such suction of the brake disc, various efforts have been made in the past.

An example of a conventional electric motor of this type is shown in FIG. 1
2 is an attracting body, in which a large number of rods 3 made of a magnetic material are embedded radially in the axial direction of the outer circumference of a disc 2 made of a non-magnetic material, and the rods 3 are fitted onto the rotor shaft 6. It is arranged in a space formed by the inner surface of the stator 4 and the rear surface of the rotor 5 (on the right side of the figure). 7 is a flange provided on the rotor shaft 6, and 9 is an elastic member, such as a disc spring, interposed between the suction body 1 and the flange 7. Reference numeral 10 denotes a locking member for the suction body 1 mounted in the annular groove 8 of the rotor shaft 6, which is composed of, for example, a two-part ring as shown in FIG.
A retainer ring 11 is fitted around the outer periphery to hold the suction body 1 in a predetermined position.

Reference numeral 12 denotes a cone-shaped brake disc, which includes an attracted object 1 having a magnetic material on at least the surface facing the attracting object 1.
3, a truncated conical disk 14 fixed thereto, and a friction plate 15 made of a material with a large friction coefficient attached to the outer circumferential surface of the disk 14, with splines, keys, key grooves, etc. It is attached to the rotor shaft 6 so that it does not rotate but is slidable in the axial direction.

A rear frame 16 supports the rear end of the rotor shaft 6 by a bearing 17 provided at its center, and a brake receiver 18 is provided on the inner surface of the conical portion. Reference numeral 19 denotes a locking member of the bearing 17 that is screwed onto the rear end of the rotor shaft 6, and a protruding piece 22 of the detent fitting 21 is bent and engaged with a groove 20 provided on the outer periphery of the locking member 19. There is.

23 is the suction body 1 and the sucked body 1 of the brake disc 12
A brake spring disposed in the annular space 24 formed by The gap between the body 1 and the sucked body 13 is maintained at a predetermined dimension.

The front end of the rotor shaft 6 (left side in the figure) is connected to an input shaft 2 of a reduction mechanism of an electric chain block, an electric traveling device, or other mechanical equipment via a connecting member 25.
6 and supported by the front frame 27 via bearings.

In the electric motor configured as described above, when the electric motor is energized, the rod 3 made of a magnetic material provided on the attracting body 1 is magnetized, and the attracted body 1 of the brake disc 12 is magnetized.
Aspirate 3. As a result, the attracted object 13 slides in the axial direction (to the left in the figure) against the spring 23, and the frictional engagement between the friction plate 15 and the brake receiver 18 is released, allowing the rotor shaft 6 to rotate. do.

At this time, even if the object 13 to be attracted is suddenly attracted and collides with the attraction object 1, and a large impact force is applied to the attraction object 1, this impact force is absorbed and alleviated by the elastic member 9, so the attraction There is no risk that the rod 3 of the body 1 will shift outward and come into contact with the stator 4, or that the attachment portions of the various parts will loosen.

Incidentally, recently, electric motors in which the rotor and the suction body are integrally combined have been proposed, but in such electric motors, as in the conventional electric motor shown in FIG. Since it is not possible to absorb and alleviate the large impact force generated by the suction of the brake disc by interposing an elastic member in the brake disc, the above-mentioned problem occurs again, and an early solution is desired.

The present invention provides the following advantages: By interposing an elastic member at the end of the rotor shaft between the bearing and the rotor shaft to reduce the impact that occurs when the brake disc is attracted,
The purpose is to solve the problems mentioned above. The present invention will be explained below using the drawings.

FIG. 4 is a longitudinal sectional view of an embodiment of the present invention. Note that parts with the same or similar functions as those in FIGS. 1 to 3 are given the same reference numerals, and explanations thereof will be omitted. 1a is a suction body, and 5a is a rotor, both of which are attached to a rotor shaft 6 and integrally connected. Reference numeral 12a denotes a brake disc, which is provided with a magnetic material at least on the surface facing the attraction body 1, and a brake receiver 18a is formed on the rear surface (on the right side in the figure). Reference numeral 16a designates a rear frame, and a friction plate 15a is attached to the opposite surface of the brake receiver 18a. The present invention provides rear bearing 1
A spring 2, such as a disc spring, is installed between the locking ring 17a of No. 7 and the washer 19a of the locking member 19 of the bearing.
This is characterized in that an elastic member 28 with a spring pressure weaker than the spring pressure of No. 3 is interposed.

Since the present invention is configured as described above, the large impact force generated when the brake disc 12a is attracted is transmitted to the rotor shaft 6 through the suction body 1a and the rotor 5a.
is transmitted to move the rotor shaft 6 forward (to the left in the figure). This impact force is applied to the elastic member 28 via the locking member 19 of the bearing 17, and is absorbed by the elastic member 28 by contracting, so that the impact force propagating to each component is significantly attenuated. Therefore, there is no risk that the rod 3 of the suction body 1 will shift outward and come into contact with the stator 4, or that the attachment parts of each component will loosen.

In the above embodiment, a case is shown in which the rotor and the suction body are integrally connected to an electric motor, but the present invention can also be implemented in a motor in which the rotor and the suction body are separated. That is, as shown in another embodiment of FIG. 5, the rotor 5 and the suction body 1 are separated as in the conventional example of FIG. 7 and is attached to the rotor shaft 6, and an elastic member 28 is interposed between the bearing 17 and the locking member 19 as in the embodiment shown in FIG. With this configuration, the impact force generated when the brake disc 12a is attracted can be absorbed and alleviated.

In the above embodiment, a flat plate-shaped friction brake is used, but a cone-shaped friction brake or a laminated plate-shaped friction brake as shown in Fig. 1 may also be used. may be attached to either the brake disc side or the frame side. Further, although a disc spring is used as the elastic member 28 according to the present invention, a coil spring or other elastic member may also be used, and the configuration and mechanism of each other component are not limited to those in this embodiment. Needless to say, the present invention is not limited to this and may be modified as appropriate without departing from the gist of the present invention.

As is clear from the above description, the present invention interposes an elastic member between the rotor shaft and the rear bearing to reduce the impact force generated when the brake disc is attracted.
Because it absorbs and alleviates the large impact force that occurs when the brake disc is suctioned, there is no risk of the rod of the suction body shifting outward or loosening of the attachment parts of each part, greatly extending the life of the motor. The effects of implementation are significant.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of an example of an electric motor equipped with a conventional suction release type brake device, Fig. 2 is a plan view of the suction body, Fig. 3 is a plan view of the locking member of the suction body, and Fig. 4
5 and 5 are longitudinal sectional views of an embodiment of the present invention, respectively. 1, 1a: suction body, 3: rod, 4: stator,
5, 5a: Rotor, 6: Rotor shaft, 7: Flange, 12, 12a: Brake plate, 15, 15a:
Friction plate, 16, 16a: frame, 17: bearing,
18, 18a: Brake receiver, 19: Locking member, 2
3: Spring, 28: Elastic member.

Claims (1)

[Scope of Claims] 1. A suction body attached to a rotor shaft, a brake disc slidably attached to the rotor shaft, and a frame having a bearing in the center that supports an end of the rotor shaft; A brake device is provided between the suction body and the brake disc and includes a spring or the like that presses a brake holder or a friction plate provided on the brake disc to a friction plate or brake holder provided on the frame, and is energized. In the electric motor configured to release the brake by attracting the brake disc with the suction body, the rotor shaft is allowed to move forward due to the impact generated when the brake disc is attracted between the bearing and the rotor shaft. An electric motor equipped with a suction release type brake device, characterized in that an elastic member is interposed to cushion the impact.