JP2011027234A - Oil adhesion prevention structure for electromagnetic brake - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent degradation of braking force of an electromagnetic brake due to oil adhesion in case of outflow of oil from a lubricant-sealed bearing. <P>SOLUTION: In the oil adhesion prevention structure for the electromagnetic brake configured to rotatably support a motor shaft 2 of an electric motor 1 through a lubricant-sealed bearing 11, and attach a brake mounting plate 18 of the electromagnetic brake 4 to the electric motor 1, an oil block section 13 is provided on an outer circumferential portion of the motor shaft 2 between the bearing 11 and the brake mounting plate 18 to block the oil which flows out of the bearing 11 and adheres to the motor shaft 2 before the brake mounting plate 18, and an oil release passage 15 is provided on the brake mounting plate 18 side to release the oil blocked by the oil block section 13 out of the electromagnetic brake 4. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a technique for preventing oil adhesion of an electromagnetic brake used in an electric motor.

2. Description of the Related Art Conventionally, in an electric motor with an electric brake used in a vehicle or the like, it is generally known to use a grease sealed type bearing that does not require refueling as a bearing that rotatably supports a motor shaft ( For example, see Patent Document 1),
However, in the unlikely event that grease leaks due to the life or damage of the bearing seal, the amount of oil transmitted through the motor shaft is very small, but it enters the electromagnetic brake and adheres to the brake braking surface. In such a case, it is expected that the braking force is reduced.

  In particular, for an electric motor with an electromagnetic brake, such as a vehicle or an elevator, where safety is a concern, there is a concern about a reduction in braking force due to oil adhesion to the electromagnetic brake.

JP 2006-71018 A

  The present invention has been invented in view of the above-described conventional problems, and even if the lubricating oil should flow out of the lubricating oil-sealed bearing, the oil can be transmitted through the motor shaft with a simple configuration to brake the electromagnetic brake. It is an object of the present invention to provide an oil adhesion prevention structure for an electromagnetic brake that can prevent intrusion into a braking surface and does not cause a reduction in braking force due to oil adhesion.

  In order to solve the above-mentioned problem, the present invention is such that the motor shaft 2 of the electric motor 1 is rotatably supported via a lubricating oil-sealed bearing 11, and is attached to the outside of the electric motor 1 on the electric motor 1 side. A brake mounting plate 18 and a brake disc 5 fixed to the end of the motor shaft 2 protruding from the electric motor 1 to the inside of the brake mounting plate 18 are provided, and the brake disc 5 is restrained and braked in a non-excited state. At the same time, the electromagnetic brake 4 is disposed to release the brake in the excited state, and flows out of the bearing 11 to the outer peripheral portion of the motor shaft 2 between the lubricant-sealed bearing 11 and the brake mounting plate 18. In addition, an oil damming portion 13 for damming the oil adhering to the motor shaft 2 before the brake mounting plate 18 is provided, and the oil damming portion 13 is provided on the brake mounting plate 18 side. Is characterized by comprising an oil release passage 15 for releasing can stop oil was outside the electromagnetic brake 4 provided.

  With such a configuration, even if oil leaks from the bearing 11 of the motor shaft 2 of the electric motor 1 and flows to the electromagnetic brake 4 side through the motor shaft 2, the oil is outside the outer periphery of the motor shaft 2. Since the oil is dammed by the oil damming portion 13 and is further released to the outside of the electromagnetic brake 4 along the oil escaping passage 15 provided on the brake mounting plate 18 side, it is ensured that the oil enters the electromagnetic brake 4. Can be prevented. In addition, the oil relief passage 15 can be easily formed by using the existing motor shaft 2 and the brake mounting plate 18 without separately using dedicated components for oil relief.

  The oil relief passage 15 is formed in a portion of the brake mounting plate 18 that faces the lower side of the oil damming portion 13, and has an inclined surface 16 that is inclined so as to gradually become lower as the distance from the oil damming portion 13 increases. In this case, the oil dripping from the oil damming portion 13 can smoothly escape to the outside of the brake mounting plate 18 along the inclined surface 16.

  Further, it is preferable that an outer surface 18a of the brake mounting plate 18 is formed with an oil outflow groove 17 having one end communicating with the lower end of the inclined surface 16 and the other end reaching the lower end of the brake mounting plate 18. In this case, the oil leakage can be easily inspected simply by palpating the lower end of the oil spill groove 17 by hand.

  In the present invention, even if the lubricating oil leaks from the lubricating oil-sealed bearing and adheres to the motor shaft, it leaks using the oil damming portion provided on the motor shaft and the oil escape passage of the brake mounting plate. Oil does not enter the electromagnetic brake and adhere to the brake braking surface, and as a result, a reduction in the braking force of the electromagnetic brake can be prevented with a simple configuration.

It is sectional drawing explaining the oil adhesion prevention structure of the electromagnetic brake of one Embodiment of this invention. It is an example of the electromagnetic brake device provided with two electromagnetic brakes same as the above, (a) is explanatory drawing of a brake operation state, (b) is explanatory drawing of a brake release state. It is a partially broken side view of an electric motor provided with the electromagnetic brake device same as the above. It is a perspective view of an electromagnetic brake device same as the above. It is a perspective view of the whole elevator system in the case of using the electric motor provided with the electromagnetic brake device same as the above in an elevator hoisting machine. It is the perspective view which looked at the lower part vicinity of the elevator system same as the above from back. It is a perspective view of the winding machine provided in the lower part of an elevator system same as the above.

  Hereinafter, the present invention will be described based on embodiments shown in the accompanying drawings.

  2A and 2B show an example of the brake operation state and the brake release state of the two electromagnetic brakes 4 and 4 built in the electromagnetic brake device 3 of the present embodiment, and FIG. 3 shows the electromagnetic brake. An example of the electric motor 1 including the device 3 is shown, and FIG. 4 shows an external perspective view of the electromagnetic brake device 3.

  The electromagnetic brake device 3 is used as, for example, a double system brake for an elevator hoisting machine 23, and two electromagnetic brakes 4 arranged in parallel along the axial direction C of the motor shaft 2 of the electric motor 1. , 4 are built in. These electromagnetic brakes 4 and 4 are mechanically independent and have functions of brake operation and brake release individually.

  Explaining one electromagnetic brake 4 (left side of FIG. 2A) close to the electric motor 1, a brake disk 5 is fixed to a motor shaft 2 that protrudes from the motor housing 24 of the electric motor 1. On one side of the brake disc 5, a fixed braking plate 6 that also serves as a brake mounting plate 18 to be described later attached to the outer wall surface of the motor housing 24 is disposed. The brake braking surface 6 a of the fixed braking plate 6 is connected to the brake disc 5. It is opposed to the brake braking surface 5a on one side.

  On the other surface side of the brake disk 5, a movable brake plate 7 is disposed oppositely. The brake braking surface 7 a of the movable braking plate 7 is opposed to the brake braking surface 5 b of the brake disc 5. The movable brake plate 7 is supported on the casing 25 side of the electromagnetic brake 4 via the guide member 26. The guide member 26 includes a guide shaft 26a attached to the casing 25 and a guide plate 26b movable along the guide shaft 26a. By attaching the movable brake plate 7 to the guide plate 26b, the movable brake plate 7 can be used as a motor shaft. 2 is supported in a movable manner in the axial direction C.

  A cylindrical yoke 10 is disposed at a position around the motor shaft 2 on the surface of the movable brake plate 7 opposite to the brake disc 5 side. The yoke 10 is fixed to the casing 25 of the electromagnetic brake 4, and a brake operation spring 8 mounted on the shaft 50 (FIG. 3) is interposed between the yoke 10 and the movable brake plate 7. The movable brake plate 7 is constantly urged toward the brake disk 5 by the spring 8. For example, six springs 8 are provided at intervals in the circumferential direction of the cylindrical yoke 10, and in the brake operation state in which each spring 8 operates (FIG. 2A), between the movable brake plate 7 and the yoke 10. The gap G is, for example, about 0.2 to 0.35 mm.

  An electromagnetic coil 9 is wound inside the cylindrical yoke 10 to form an electromagnet. When the electromagnetic coil 9 is energized, the movable brake plate 7 is electromagnetically attracted against the urging force of the spring 8. The brake is released.

  The other electromagnetic brake 4 (on the right side of FIG. 2A) far from the electric motor 1 has the same structure as that of the one electromagnetic brake 4, and corresponding parts are denoted by the same reference numerals. In this example, a brake braking surface 6 a that can contact the brake disc 5 of the other electromagnetic brake 4 is attached to the outer surface of the yoke 10 of one electromagnetic brake 4. The yoke 10 also serves as the fixed braking plate 6 of the other electromagnetic brake 4.

  Further, an encoder 27 for magnetically detecting the rotation angle of the motor shaft 2 is attached to the outer surface of the casing 25 of the electromagnetic brake 4 as shown in FIG. The encoder 27 is supported on the motor shaft 2 via a bearing 11 '.

In addition to the bearing 11 ′ of the encoder 27, the motor shaft 2 is provided with a bearing 11 that is rotatably supported by the motor housing 24 of the electromagnetic brake device 3 as shown in FIG. For these bearings 11 (same for 11 '), for example, a contact seal type grease-sealed bearing in which about 4.86 cm ³ of grease is sealed is used. In FIG. 2, 11 is an outer ring, 11b is an inner ring, and 11c is a roller.

  When the two independent electromagnetic brakes 4, 4 having the above-described configuration are not energized, the movable brake plate 7 is urged by the spring 8 in the direction of arrow e in FIG. When the electromagnetic brakes 4 and 4 are energized simultaneously, the movable brake plate 7 is electromagnetically attracted in the direction indicated by the arrow d in FIG. 2B, and the brake is released.

  Here, in this invention, the electromagnetic brake device 3 arrange | positioned adjacent to the exterior of the electric motor 1 is provided with the brake attachment board 18 attached to the electric motor 1 side. In this example, the inner surface of the brake mounting plate 18 serves as the fixed braking plate 6.

  Further, as shown in FIG. 1, a step for attaching the hub 14 is provided on the outer peripheral portion of the motor shaft 2 between the lubricant-sealed bearing 11 and the brake mounting plate 18. In addition to the function of fixing the brake disc 5, the hub 14 also has a function as an oil damming portion 13 for damming the oil that flows out of the bearing 11 and adheres to the motor shaft 2 before the brake mounting plate 18. is doing.

  The brake mounting plate 18 is provided with an oil release passage 15 for releasing the oil blocked by the oil blocking portion 13 to the outside of the electromagnetic brake 4.

  The oil relief passage 15 of this example is composed of an inclined surface 16 provided on the brake mounting plate 18 and an oil outflow groove 17 provided on the outer side surface 18 a of the brake mounting plate 18. The inner peripheral surface 18b on the center side of the brake mounting plate 18 is the other end side in the axial direction (outer side surface 18a of the brake mounting plate 18) than the opening dimension on one end side in the axial direction C (inner side surface of the brake mounting plate 18). The side of the inner peripheral surface 18b located below the oil damming portion 13 is separated from the oil damming portion 13 (brake mounting plate). The inclined surface 16 is inclined so as to become gradually lower toward the outer surface 18a side). Further, an oil outflow groove 17 is formed on the outer surface 18a of the brake mounting plate 18 so as to linearly extend in the vertical direction from the center portion toward the lower end portion, and one end of the oil outflow groove 17 is the inclined surface 16. The other end reaches the lowest end of the brake mounting plate 18. As a result, oil relief paths G1 to G4 are formed which are connected to the bearing 11 → the motor shaft 2 → the oil damming portion 13 → the inclined surface 16 → the oil outflow groove 17.

  If the oil leaks from the inside of the lubricating oil-sealed bearing 11, it tries to enter the electromagnetic brake 4 side through the motor shaft 2, but it is provided on the outer periphery of the motor shaft 2. The oil damming portion 13 does not enter the electromagnetic brake 4 any more. Further, the oil dammed up by the oil damming portion 13 drips onto the inclined surface 16 of the brake mounting plate 18 positioned below the oil damming portion 13 and travels along the inclined surface 16 to the outside of the brake mounting plate 18. And is guided to the outside of the electromagnetic brake 4 through an oil outlet groove 17 formed in the vertical direction on the outer surface 18a of the brake mounting plate 18. Therefore, no oil adheres to the brake braking surfaces 5a, 5b, 6a, and 7a in the electromagnetic brake 4, and a reduction in braking force of the electromagnetic brake 4 can be prevented. In addition, since the two electromagnetic brakes 4 of this example are provided with four brake braking surfaces 5a, 5b, 6a, and 7a, the possibility that the four surfaces are contaminated with oil is extremely low. Even if the brake braking surfaces 5a and 6a located in the vicinity of the electric motor 1 are soiled, the braking force and the restraining force of the motor shaft 2 can be sufficiently maintained by the other three surfaces.

  In addition, the oil leakage can be easily inspected by simply palpating the lower end portion of the oil outflow groove 17 of the brake mounting plate 18. Therefore, it is not necessary to disassemble the electric motor 1 at the palpation stage, and maintenance can be easily performed.

  FIGS. 5-7 has shown an example at the time of using the electromagnetic brake apparatus 3 provided with the oil adhesion prevention function of this invention for the electric motor 1 of the hoisting machine 23 of an elevator. In this elevator, a main rope 21 is connected to an elevator car 20, the main rope 21 is moved up and down by a hoisting machine 23, and the elevator car 20 is moved up and down along a hoistway 22 in a vertical direction. The hoisting machine 23 of the present example is disposed at the lower end of the hoistway 22, and as shown in FIG. 7, an electric motor 1 including an electromagnetic brake device 3 incorporating two electromagnetic brakes 4 and 4, A reduction gear 30 that obtains a target torque by lowering the motor rotation speed of the electric motor 1 with a worm gear, and a drive drum 31 connected to the electric motor 1 via the reduction gear 30 are provided. 5, 32 is a landing door opening / closing device, 33 is a car door opening / closing device, 34 is a power control panel for normal travel control, and 35 is an electromagnetic contactor for turning on and off the electric motor 1 of the hoisting machine 23.

  Thus, as in the above embodiment, even if the lubricating oil leaks from the bearing 11 of the lubricating oil sealing type, it does not adhere to the brake braking surface, and it is possible to prevent the braking force of the electromagnetic brake 4 from being lowered. In addition, by using the electromagnetic brake device 3 including the two electromagnetic brakes 4 and 4 for the electric motor 1 of the elevator hoisting machine 23, a highly safe dual system brake is provided. There is an effect that the elevator hoisting machine 23 can be realized.

  The oil brake prevention structure of the electromagnetic brake according to the present invention is widely applied to the electromagnetic brake 4 used in the vehicle and various electric motors 1 in addition to the electromagnetic brake 4 of the elevator hoisting machine.

  Further, the number of electromagnetic brakes 4 is not limited to two, and may be one or three or more.

DESCRIPTION OF SYMBOLS 1 Electric motor 2 Motor shaft 3 Electromagnetic brake device 4 Electromagnetic brake 5 Brake disc 11 Bearing 13 Oil dam stop 15 Oil relief passage 16 Inclined surface 17 Oil outflow groove 18 Brake mounting plate

Claims (3)

  A motor shaft of the electric motor is rotatably supported via a lubricating oil-sealed bearing, a brake mounting plate attached to the motor side outside the motor, and a motor shaft protruding from the motor to the inside of the brake mounting plate And a brake disc that is fixed to the end of the motor, and is provided with an electromagnetic brake that restrains the brake disc in a non-excited state to apply the brake and releases the brake in the excited state. An oil damming section is provided on the outer periphery of the motor shaft between the bearing and the brake mounting plate to block the oil that flows out of the bearing and adheres to the motor shaft before the brake mounting plate. An electromagnetic brake characterized in that an oil release passage is provided on the plate side for releasing the oil blocked by the oil blocking portion to the outside of the electromagnetic brake. Oil adhesion prevention structure.   The oil relief passage is formed in a portion of the brake mounting plate that faces the lower side of the oil damming portion and has an inclined surface that is inclined so as to gradually become lower as the distance from the oil damming portion increases. Item 10. The structure for preventing oil adhesion of an electromagnetic brake according to Item 1. 3. The electromagnetic brake according to claim 2, wherein an oil outflow groove is formed on the outer surface of the brake mounting plate so that one end communicates with the lower end of the inclined surface and the other end reaches the lower end of the brake mounting plate. Oil adhesion prevention structure.

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