JP2007205390A - Motor brake - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor brake suitable for a motor driven winch. <P>SOLUTION: The motor brake 9 comprises a brake disc 12 to be rotated together with a motor shaft 2, a friction plate 13 to be put in slide contact with the brake disc 12 for braking the rotation of the motor shaft 2, a brake spring 11 for pushing the friction plate 13 against the brake disc 12, an electromagnetic coil 15 for separating the friction plate 13 from the brake disc 12 against the brake spring 11, a manual brake releasing mechanism 20 for separating the friction plate 13 from the brake disc 12 against the brake spring 11, and a centrifugal force brake mechanism 50 for braking the rotation of the motor shaft 2 with the centrifugal force of a governor weight 54 to be turned together with the motor shaft 2. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an improvement in a motor brake that is provided in, for example, an electric motor and brakes the rotation of a motor shaft.

  For example, in the case of an electric winch that moves up and down a lifeboat provided in a mother ship, it is necessary to provide a motor brake that brakes the rotation of a motor shaft in the electric motor.

Conventionally, as this type of motor brake, there has been one that brakes rotation of a motor shaft by an urging force of a brake spring and releases braking by energizing an electromagnetic coil (see Patent Document 1).
JP 2005-308109 A

  However, in such a conventional motor brake, for example, when the power supply fails, the electromagnetic coil cannot be energized, so that the braking of the motor shaft cannot be released.

  For this reason, for example, when the lifeboat is raised and lowered by the electric winch, there is a problem that the lifeboat cannot be thrown in when the power supply fails.

  In addition, there has been a demand to limit the speed of a lifeboat that falls by its own weight when the braking mechanism of the motor brake is malfunctioning.

  The present invention has been made in view of the above problems, and an object thereof is to provide a motor brake suitable for an electric winch or the like.

  The present invention relates to a motor brake that brakes rotation of a motor shaft, a brake disc that rotates together with the motor shaft, a friction plate that slides on the brake disc and brakes rotation of the motor shaft, and presses the friction plate against the brake disc A brake spring, an electromagnetic coil that separates the friction plate from the brake disc against the brake spring, a manual brake release mechanism that separates the friction plate from the brake disc against the brake spring, and a governor weight that rotates with the motor shaft. And a centrifugal brake mechanism that brakes the rotation of the motor shaft by centrifugal force.

  According to the present invention, the rotation of the motor shaft is braked by the urging force of the brake spring when the electromagnetic coil is not energized. Even when the electromagnetic coil is not energized, the manual brake release mechanism is operated to release the braking of the motor shaft. In addition, it is possible to brake the rotation of the motor shaft by operating the centrifugal brake mechanism during high-speed rotation of the motor shaft.

  Thus, for example, when a lifeboat provided in a mother ship is raised and lowered by an electric winch, braking of the electric winch can be manually released even when the power supply fails, and the lifeboat can be thrown in by lowering its own weight.

  In addition, when the manual brake release mechanism or the like malfunctions, the speed of the lifeboat that descends its own weight can be limited by the operation of the centrifugal brake mechanism.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  An electric motor 1 shown in FIG. 1 is provided in an electric winch. The electric winch is used for raising and lowering a lifeboat provided in a mother ship, for example.

  In the electric motor 1, a motor shaft 2 is rotatably supported by a casing 3 via a bearing 4. The motor shaft 2 is rotationally driven by electromagnetic force acting on a rotor (not shown).

  The electric motor 1 includes an electromagnetic brake 10 that brakes the rotation of the motor shaft 2 and a centrifugal force brake mechanism 50, and the braking force of the motor shaft 2 is adjusted by the electromagnetic brake 10, and the motor shaft 2 has a rotational speed that is a predetermined value or more. When reaching, the centrifugal brake mechanism 50 brakes the rotation of the motor shaft 2.

  The electromagnetic brake 10 presses the brake disk 12 against the friction plate 13 and the friction plate 14 by the urging force of the brake spring 11 to brake the motor shaft 2, and the friction force is applied to the brake plate 11 against the brake spring 11 by the electromagnetic force of the electromagnetic coil 15. Release the brake disc 12 to release the braking.

  A guide sleeve 17 is fitted to the motor shaft 2, and the brake disc 12 is coupled to the motor shaft 2 so as to be slidable in the axial direction. The guide sleeve 17 is prevented from rotating with respect to the motor shaft 2 via a key 16. The brake disk 12 is prevented from rotating with respect to the guide sleeve 17 via the spline 18.

  The friction plate 14 is fixed to the casing 3 via a fastening member (not shown). The brake disk 12 is interposed between the friction plate 14 and the friction plate 13. The friction plate 13 is interposed between the brake disk 12 and the casing 3.

  An electromagnetic coil 15 is embedded in the casing 3, and a plurality of brake springs 11 are interposed around the electromagnetic coil 15. Each brake spring 11 has a coil shape and is interposed between the casing 3 and the friction plate 13 in a compressed state.

  When the electromagnetic coil 15 is not energized, the brake disk 12 is pressed against the friction plate 14 via the friction plate 13 by the urging force of each brake spring 11 to brake the motor shaft 2. When the electromagnetic coil 15 is energized, the friction force is released from the brake disk 12 against the brake springs 11 by the electromagnetic force to release the braking. The braking force can be arbitrarily adjusted by controlling the electric power for exciting the electromagnetic coil 15.

  The electric motor 1 includes a manual brake release mechanism 20 that manually releases the electromagnetic brake 10. The manual brake release mechanism 20 includes a governor outer ring 51 that manually moves in the axial direction of the motor shaft 2, and the cylindrical governor outer ring 51 is slidably interposed in the casing 5. When the tip 51a of the governor outer ring 51 is pressed against the friction plate 13, the friction plate 13 is separated from the brake disk 12 against the brake springs 11 to release the braking.

  The manual brake release mechanism 20 functions as a mechanism for driving the governor outer ring 51, a handle 21 that is manually rotated, an operation shaft 22 that moves in the axial direction of the motor shaft 2 as the handle 21 rotates, and this operation. And a deflection disk 23 for transmitting the displacement of the shaft 22 to the governor outer ring 51.

  The outer peripheral portion 23 c of the flexible disk 23 is fastened to the proximal end portion 51 b of the governor outer ring 51. The operation shaft 22 is connected to the central portion 23 a of the bending disk 23 via a retaining ring 27, and the operation shaft 22 pushes the central portion 23 a of the bending disk 23 to drive the governor outer ring 51.

  The flexible disk 23 has a thin disc-shaped spring plate portion 23b, and the spring plate portion 23b is elastically deformed to transmit the displacement of the operation shaft 22 to the governor outer ring 51.

  The operation shaft 22 has a screw portion 22 a, and this screw portion 22 a is provided by being screwed into the screw hole 6 a of the casing 6.

  The operation shaft 22 has a journal portion 22 b, and the journal portion 22 b is slidably supported by the bearing portion 6 b of the casing 6. An O-ring 24 is interposed between the journal portion 22b and the bearing portion 6b to seal the both. A handle 25 is fastened to the operation shaft 22.

  When the operator rotates the handle 25 in one direction, the operation shaft 22 moves forward with respect to the casing 6, and the governor outer ring 51 moves rightward in FIG. It moves against the spring 11 and releases the brake by separating the friction plate 13 from the brake disk 12.

  When the operator rotates the handle 25 in the other direction, the operation shaft 22 moves backward with respect to the casing 6, and the governor outer ring 51 moves to the left in FIG. It is moved by the urging force of the spring 11, and the friction plate 13 is pressed against the brake disc 12 for braking.

  As shown in FIG. 2, the centrifugal brake mechanism 50 is provided inside the governor outer ring 51. The centrifugal brake mechanism 50 has a flange 53 coupled to the motor shaft 2, a pair of governor weights 54 rotatably connected to the flange 53 via pins 55, and the governor weights 54 attached in the closing direction. A governor return spring 56 is provided.

  The disc-shaped flange 53 is fitted to the motor shaft 2 along with the sleeve 17, is prevented from coming off via a retaining ring 57, and is prevented from rotating relative to the motor shaft 2 via a key 16.

  The pair of governor weights 54 are arranged symmetrically with respect to the rotation center axis of the motor shaft 2. The governor weight 54 has an outer peripheral surface 54a that is in sliding contact with the governor outer ring 51. When the governor weight 54 expands against the governor weight 54 due to the centrifugal force acting as the motor shaft 2 rotates, the outer peripheral surface 54a is pressed against the governor outer ring 51. The rotation of the motor shaft 2 is braked.

  The electric motor 1 is configured as described above, and the braking force applied to the motor shaft 2 is adjusted by the electromagnetic brake 10, the manual brake release mechanism 20, and the centrifugal brake mechanism 50.

  As described above, the motor brake 9 brakes the rotation of the motor shaft 2 by slidingly contacting the both sides of the motor disc 2 that rotates with the motor shaft 2, the brake disc 12 that rotates together with the motor shaft 2, and the brake shaft 12. The friction plate 13 and the friction plate 14, the brake spring 11 that presses the friction plate 13 against the brake disc 12, the electromagnetic coil 15 that separates the friction plate 13 from the brake disc 12 against the brake spring 11, and the brake spring 11 And a manual brake release mechanism 20 that separates the friction plate 13 from the brake disk 12 and a centrifugal force brake mechanism 50 that brakes the rotation of the motor shaft 2 by the centrifugal force of the governor weight 54 that rotates together with the motor shaft 2. For example, the manual brake release mechanism 20 is By releasing the braking of the motor shaft 2, the electric motor 1 can be automatically rotated by gravity applied to the load, and the centrifugal brake mechanism 50 is operated when the motor shaft 2 rotates at a high speed. 2 can be limited.

  Thus, for example, when a lifeboat provided in a mother ship is raised and lowered by an electric winch, braking of the electric winch can be manually released even when the power supply fails, and the lifeboat can be thrown in by lowering its own weight.

  If the manual brake release mechanism 20 or the like malfunctions when the lifeboat is lowered by its own weight, the speed of the lifeboat can be limited by operating the centrifugal brake mechanism 50.

  The centrifugal force brake mechanism 50 includes a governor outer ring 51 for slidingly contacting a governor weight 54. The motor outer ring 51 is provided so as to be movable in the axial direction of the motor shaft 2, and the manual brake release mechanism 20 is provided with the governor outer ring 51 attached to the motor shaft 2. Since the friction plate 13 is separated from the brake disk 12 against the brake spring 11 by moving in the axial direction, the number of parts constituting the manual brake release mechanism 20 is reduced, and the motor brake 9 can be downsized.

  Since the manual brake release mechanism 20 includes the operation shaft 22 that is manually moved in the axial direction of the motor shaft 2 and the bending disk 23 that transmits the displacement of the operation shaft 22 to the governor outer ring 51, the elastic restoring force of the bending disk 23 is provided. Thus, the friction plate 13 can be driven so that the elastic restoring force of the brake spring 11 is balanced, and the braking force of the motor shaft 2 can be finely adjusted.

  The bending disk 23 includes an outer peripheral end portion 23c coupled to the governor outer ring 51, a central portion 23a coupled to the operation shaft 22, and a disc-shaped spring plate portion 23b connecting the outer peripheral end portion 23c and the central portion 23a. Therefore, the governor weight 54 is disposed on the inner side of the governor outer ring 51 and the flexible disk 23, and the motor brake 9 can be downsized.

  The present invention is not limited to the above-described embodiment, and it is obvious that various modifications can be made within the scope of the technical idea.

  The motor brake of the present invention can be used for an electric winch or other devices.

Sectional drawing of the motor brake which shows embodiment of this invention. Sectional drawing which follows the AA line of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric motor 2 Motor shaft 9 Motor brake 11 Brake spring 12 Brake disk 13, 14 Friction plate 15 Electromagnetic coil 20 Manual brake release mechanism 22 Operation shaft 23 Bending disk 23a Bending disk center part 23b Bending disk spring board part 23c Bending disk outer peripheral edge part 50 Centrifugal brake mechanism 51 Governor outer ring 54 Governor weight

Claims (4)

In the motor brake that brakes the rotation of the motor shaft,
A brake disc that rotates with the motor shaft;
A friction plate sliding on the brake disc to brake the rotation of the motor shaft;
A brake spring that presses the friction plate against the brake disc;
An electromagnetic coil that separates the friction plate from the brake disc against the brake spring;
A manual brake release mechanism for separating the friction plate from the brake disc against the brake spring;
A motor brake, comprising: a centrifugal force brake mechanism that brakes rotation of the motor shaft by a centrifugal force of a governor weight that rotates together with the motor shaft.   Provided with a governor outer ring that slidably contacts the governor weight that expands by centrifugal force, the motor outer ring is provided so as to be movable in the axial direction of the motor shaft, and the manual brake release mechanism moves the governor outer ring in the axial direction of the motor shaft. The motor brake according to claim 1, wherein the friction plate is separated from the brake disk against the brake spring.   The said manual brake cancellation | release mechanism is provided with the operation shaft which moves to the axial direction of the said motor shaft by a manual operation, and the bending disk which transmits the displacement of this operation shaft to the said governor outer ring | wheel. Motor brake.   The flexible disk includes an outer peripheral end portion coupled to the governor outer ring, a central portion coupled to the operation shaft, and a spring plate portion connecting the outer peripheral end portion and the central portion. Item 4. The motor brake according to item 3.

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