JPS6151174B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a brake device, and particularly to a brake device suitable as a safety brake for a hoist or the like.

[Conventional technology]

This type of braking device senses the falling speed of the load as centrifugal force, rotates the brake shoe using a centrifugal unit, and moves a certain amount in the axial direction, causing the brake wheel attached to the shaft to be braked to act as the brake shoe. Recently, a brake device has been proposed that brakes the rotation of a braked shaft by being clamped between the brake disk and the brake disk.

[Problem that the invention seeks to solve]

However, in such a brake device, since the amount of movement of the brake shoe is constant, the braking force of the brake is also constant, and there is a problem that the braking force is too strong or too weak compared to the required braking force. Ta.

For this reason, it has been considered to adjust the mounting position of the brake case, as in the brake device of JP-A No. 54-123663, but the adjustment device loosens during driving and the brake no longer exerts any braking force. No consideration was given to the situation.

[Means for solving problems]

The present invention has been made to solve this problem, and the present invention is directed to the braked shaft 8; Centrifugal piece 1 that pops out toward the outer circumference
5, a brake shoe 17 that engages with and rotates the centrifugal piece 15 when the centrifugal piece 15 protrudes in the outer circumferential direction, and a brake shoe 17 that moves in the axial direction when the centrifugal piece 15 rotates. It includes a supporting brake cover 18, and a brake wheel 12 attached to the braked shaft 8 so as to rotate therewith and to be movable in the axial direction,
By pressing the brake shoe 17 against the brake wheel 12 by moving the brake shoe 17 in its axial direction and clamping the brake wheel 12 between the brake shoe 17 and the brake disc 11, the rotation of the braked shaft 8 is controlled. In the brake device configured to brake the brake cover 18, a plurality of long holes 21 extending in the circumferential direction are provided in the outer peripheral part of the brake cover 18,
The brake device is characterized in that the brake cover 18 is attached to the brake case 13 by passing attachment bolts 20 through the elongated holes 21, respectively.

[Effect]

According to this brake device, after assembling the brake device, the braking force of the brake is measured, and if the braking force is too strong or too weak, the mounting bolts 20 are loosened and the brake cover 18 is rotated in a predetermined direction. After the movement, a predetermined braking force can be obtained by tightening the mounting bolt 20.

Furthermore, if the mounting bolts 20 loosen during operation of such a brake device, the brake cover 18 will rotate, but the mounting bolts 20 will come into contact with the end face of the elongated hole 21, preventing further rotation of the brake cover 18. Since the braking force is prevented, the braking force of the brake does not become completely ineffective, and the braking force can always be maintained.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on FIGS. 1 to 6.

FIG. 1 shows a longitudinal sectional side view of a hoist to which a brake device according to the present invention is applied. In the drawing, reference numeral 5 denotes a main body frame, and a drive motor 2 is attached to one end of the main body frame. A main brake device 1 is attached to the outer end surface of the drive motor 2, and the main brake device 1 brakes the motor 2 to a stop when the motor 2 is deenergized. On the other hand, the shaft of the electric motor 2 is transmitted through the center of the main body frame 5 by the connecting shaft 4 to the reduction gear device 6 attached to the other end of the main body frame 5, and is decelerated and boosted by the reduction gear, and then transferred to the final stage gear. rotates the hanging rope drum 3 within the main body frame 5. The shaft of the electric motor 2 is extended to the outer end of the reduction gear 6 by a coupling shaft 4 and a braked shaft 8 in the reduction gear 6, and is braked by a safety brake device 7 according to the invention.

FIG. 2 shows a longitudinal sectional side view of the safety brake device 7, and FIG. 3 shows the operation of FIG. 2. Further, FIGS. 4 and 5 show a cross-sectional view taken from FIG. 2, and FIG. 6 shows a partial cross-sectional view taken from FIG. 2.

The braked shaft 8 is passed through the brake case 13,
A straight tooth spline is formed in the extension, on which the brake wheel 12 is mounted so as to be non-rotatable but movable in the axial direction with respect to the shaft. Furthermore, a centrifugal piece support 14 is fixed to the end of the braked shaft 8. Notches are formed at equal intervals on the outer periphery of the centrifugal piece support 14, and the centrifugal pieces 15 are arranged in these notches. Each centrifugal piece 15 has a support pin, and a ring spring 16 is passed over the support pin on both sides of the centrifugal piece support 14 so as to press each centrifugal piece 15 against the bottom of the section. A brake disk 11 is engaged with a convex portion of the brake case 13 so as to be movable in the axial direction. A spring seat is formed in a brake case 13 corresponding to the brake disc 11 concentrically with the shaft, and a disc spring 10 is attached to the spring seat to enable the brake disc 11 to be elastically retracted. Reference numeral 17 denotes a brake shoe in the shape of an inner cylinder with a bottom, and the outer peripheral surface of the cylindrical part is rotatable on the inner peripheral surface of the cylindrical part of the brake cover 18 attached to the brake case 13, and is concentric with the shaft to be braked 8. Supported. The opening end flange of the brake shoe 17 extends outward, and the brake wheel 12 is interposed between this flange and the brake disk 11. The inner circumferential surface of the cylindrical part of the brake shoe 17 faces the outer circumferential surface of the centrifugal piece 15, and when the centrifugal piece 15 jumps out due to over-rotation of the braked shaft 8 in the hoist's load-unloading direction, the two will be in friction. They make contact and rotate the brake shoes 17 in the same direction. The flange of the brake shoe 17,
The surface of the brake cover 18 relative to this flange has circumferentially inclined surfaces 17' and 1 that contact each other.
8' and the rotation of the brake shoe 18 causes the brake shoe 18 to move forward toward the brake wheel 12.

In the above configuration, the hoist normally rotates the drum 3 using the drive motor 2 and the main brake 1 to hoist, lower, and stop the suspended load.

If the main brake 1 fails and loses braking force during such cargo handling work (particularly during a braking stop), the suspended load will reversely drive the hoist due to its own weight and fall. When the suspended load begins to fall in this manner, the rotational speed of the shaft of the electric motor 2 increases, and when it reaches a predetermined critical rotational speed, the centrifugal piece 15 resists the ring spring 16 and jumps outward, causing the brake shoe 17 to It comes into contact with the inner peripheral surface of the cylindrical part. As a result, the centrifugal piece 15 of the brake shoe 17
It rotates as it is dragged by the slanted surfaces 17' and 18' and moves in the axial direction (toward the brake wheel mouth). The brake shoe 17 moves to clamp the brake wheel 12 between it and the brake disc 11. In addition, the brake shoe 17 is dragged and rotated by the frictional force between the flange and the brake wheel 12.
is further pressed between the brake disc 11 and the brake shaft 8 is braked by the frictional force of the clamping surface. As shown in FIG. 6, the rotation of the brake shoe 17 is stopped when the protrusion at the tip of the flange of the brake shoe 17 comes into contact with the protrusion on the inner peripheral surface of the brake case 13. At this time, the contact position between the inclined surface 17' of the brake shoe 17 and the inclined surface 18' of the brake cover 18 determines the amount of movement of the brake shoe 17 in the direction of the brake disk 11, which becomes the amount of deflection of the disc spring 10. The reaction force of the lever becomes the braking force of the braked shaft 8.

When the inclined surface 18' of the brake cover 18 is moved clockwise and fixed, the brake cover 18 is moved against the inclined surface 17' of the brake shoe 17.
The inclined surface 18' of will bite more,
The amount of movement of the brake shoe 17 with respect to the brake disk 11 increases, the amount of deflection of the disc spring 10 increases, and the braking force of the brake shaft 8 increases.

Furthermore, when the inclined surface 18' of the brake cover 18 is moved counterclockwise and fixed, the amount of movement of the brake shoe 17 relative to the brake disk 11 is reduced, and the braking force of the brake shaft 8 is reduced. In order to make the fixing position of the inclined surface 18' of the brake cover 18 adjustable, holes for the mounting bolts 20 are provided in the elongated holes 21 (sixth Figure).
A plurality of the elongated holes 21 are provided on the outer periphery of the brake cover 18 so as to extend in the circumferential direction.

Therefore, when assembling or adjusting, by loosening the screws 20 and changing the mounting position of the brake cover 18 with respect to the brake case 13, the inclined surfaces 17', 1 at the maximum rotation angle of the brake shoe 17 can be adjusted.
The height of the engagement surface 8' (the amount of axial movement of the brake shoe 17) can be set arbitrarily. In this case, since the adjustment range is limited to the range of the elongated hole 21, the brake function will not be impaired due to erroneous adjustment to a more than necessary range.

〔Effect of the invention〕

According to the brake device of the present invention, the mounting bolt 2
A predetermined braking force can be obtained by simply tightening the mounting bolt 20 after loosening the bolt 0 and rotating the brake cover 18 in a predetermined direction, and even if the mounting bolt 20 is loosened, a certain amount of braking force can be obtained. , it can have good performance and high reliability.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal side view of a hoist to which a brake device according to the present invention is applied, FIG. 2 is a longitudinal side view of a brake device according to the present invention, FIG. Figure, 5th
The figures are each a cross-sectional view of FIG. 2, and FIG. 6 is a partial cross-sectional view of FIG. 2. 1... Main brake device, 2... Electric motor, 3...
Drum, 4...Connection shaft, 5...Frame,
6...Deceleration device, 7...Safe brake device, 8...
...braked shaft, 9...bearing, 10...disc spring, 11
... Brake disk, 12 ... Brake wheel, 13 ... Brake case, 14 ... Centrifugal piece support, 15 ... Centrifugal piece, 16 ... Ring spring, 17 ...
... Brake shoe, 17'... Brake shoe slope, 18... Brake cover, 18'... Brake cover slope, 19... Return spring, 20
……bolt.

Claims (1)

[Claims] 1 A braked shaft 8, a centrifugal piece 15 that flies out toward the outer periphery due to the centrifugal force when the rotational speed reaches a predetermined number of rotations or more when rotating together with the braked shaft 8, and this centrifugal piece 15 moves toward the outer periphery. The brake shoe 1 engages with this centrifugal piece 15 and rotates when the brake shoe 1 jumps out in the direction
7, a brake cover 18 that supports the brake shoe 17 so as to move in the axial direction when the brake shoe 17 rotates, and a brake cover 18 that is attached to the braked shaft 8 so that it can rotate together with the brake shoe 17 and move in the axial direction. and a brake wheel 12, the brake shoe 17 is pressed against the brake wheel 12 by movement in the axial direction, and the brake wheel 12 is clamped between the brake shoe 17 and the brake disk 11. In this brake device, a plurality of elongated holes 21 extending in the circumferential direction are provided in the outer peripheral part of the brake cover 18, and the mounting bolts 20 are passed through the elongated holes 21, respectively. A brake device characterized in that a brake cover 18 is attached to a brake case 13.