JPS5943654B2 - Brake device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a brake device, and particularly to a brake device suitable as a safety brake for hoists and the like.

This type of brake device detects the falling speed of the load as centrifugal force, rotates the brake shoe using a centrifugal unit, and moves the brake shoe in the axial direction, moving the brake wheel attached to the shaft to be braked between the brake shoe and the brake disc. Recently, a brake device has been proposed that brakes the rotation of a braked shaft by clamping the shaft between the shafts.

FIG. 1 is a longitudinal sectional side view of a hoist to which this brake device is applied.

In this figure, 1 is a main body frame, and a driving electric motor 2 is attached to one end surface of the main body frame.

A main brake 3 is attached to the outer end surface of the drive motor 2.
The motor shaft 2A extended toward the end face is braked to a stop by the main brake 3 when the motor 2 is deenergized.

On the other hand, the motor shaft 2A passes through the center of the main body frame 1 and extends outside the other end surface of the main body frame 1.

A gear case 4 is attached to the other end surface of the main body frame 1, and a reduction gear 5 housed in the gear case 4 is connected to the motor shaft 2.
The final stage gear 5A rotates the hanging load rope drum 6 within the main body frame 1 by decelerating and increasing the rotation of A.

The motor shaft 2A is extended to the outer end of the gear case 4 (
The outer end of the gear case 4 is braked by the safety brake 7 according to the above proposal.

Fig. 2 is an enlarged detailed sectional view of the safety brake 7, Fig. 3 is a sectional view taken along line A-A in Fig. 2, Figs. 4 and 5 are front views of the centrifugal unit, and Fig. 4 is a non-operating one. The state and FIG. 5 respectively show the operating state.

A straight tooth spline 2B is formed on the extension of the motor shaft 2A, and a brake wheel 8 is attached thereto so as to be non-rotatable and movable in the axial direction relative to the shaft Q.

A centrifugal piece support 9 is fixed to the end of the extension of the motor shaft 2A, and a notch 9A is formed on the outer periphery of the centrifugal piece support 9.
8B and 9C are formed at equal intervals, and here (this centrifugal piece 10
A, 10B, and IOC are arranged.

Each centrifugal piece 10A to 10C is a support pin 11A. 11B, 1
1C, and is pressed against the bottoms of the notches 9A to 9C by extending the ring springs 12A and 12B to the outside of the support pins 11A to 11C on both sides Q of the centrifugal piece support 9.

Reference numeral 13 denotes a brake cover, which is secured to the end surface of the gear case 14 by a case retainer 16 with screws 15, so that the gear case 1
41, and is mounted so that its rotational position can be adjusted.

Reference numeral 17 denotes an annular brake disc, which is supported non-rotatably and movably in the axial direction relative to the gear case 14, and is elastically retractable by a disc spring 18.

19 is a cylindrical brake shoe with a bottom, and the cylindrical portion 19
The outer peripheral surface of A is fitted with the brake cover 13 through the threaded portion 19B, so that it is supported concentrically with the motor shaft 2A.

The open end flange 19C of the brake shoe 19 extends radially outward, and the brake wheel 8 is interposed between the flange 19C and the brake disc 17.

Further, a protrusion 19D that protrudes outward is formed on the outer periphery of the opening end flange 19C of the brake shoe 19, and -
Corresponding to this protrusion 19D, a protrusion 14A that protrudes inward is formed on the inner periphery of the key case 14, and when the brake shoe 19 rotates, these protrusions 19D and 14
A collide with each other to prevent the brake shoe 19 from rotating any further.

The inner peripheral surface of the cylindrical portion 19A of the brake shoe 19 is the centrifugal piece 1.
The centrifugal pieces 10A to 10C face the outer circumferential surfaces of the centrifugal pieces 10A to 10C, and when the centrifugal pieces 10A to 10C fly out due to overrotation of the motor shaft 2A in the hoist's load-unloading direction, they come into frictional contact with each other and press the brake shoe 19. They are designed to rotate in the same direction.

The characteristics of the threaded portion 19C are set so that the brake shoe 19 advances toward the brake wheel 8 due to this rotation.

Reference numeral 20 denotes an annular rubber seal having an angular cross-section, and is attached by fitting an inward protrusion 20A at one end of its outer periphery into an annular groove 13A at the end of the brake cover 13. It contacts the outer circumferential surface of the portion 19A and seals the gap between the threaded portion of the brake cover 1.3 and the brake disc 19.

The inner diameter of this rubber seal 20 is the same as that of the brake shoe 19.
The inner periphery of the rubber seal 20 is expanded when it is installed, and the elastic force caused by this deformation is much smaller than the rotational force of the brake shoe 19 when the load accelerates and falls. Although it is small, it is adjusted so that it is larger than the rotational force of the brake shoe 19 due to vibration during normal operation.

In the above configuration, the hoist normally rotates the drum 6 using the drive motor 2 and the main brake 3 to hoist, lower, and stop the suspended load.

If the main brake 3 fails and loses braking force during such cargo handling work, especially 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 way, the motor shaft 2A
When the rotation speed increases and reaches the planned critical rotation speed,
As shown in FIG.
2A and 12B, and comes into contact with the inner circumferential surface of the cylindrical portion 19A of the brake shoe 19.

As a result, the brake shoe 19 is attached to the centrifugal pieces 10A to 10.
C, it rotates, and moves in the axial direction, that is, in the direction of the brake wheel 8, by the action of the threaded portion 19B.

When the brake shoe 19 moves and clamps the brake wheel 8 with the brake disc 17, a frictional force is generated on the clamping surface and the motor shaft 2A is braked.

At the same time, the brake shoe 19 is dragged and rotated by the frictional force between the flange 19C and the brake wheel 8, so the rotation of the brake shoe 19 rapidly accelerates and presses the brake wheel 8, causing the brake The disc spring 18 is bent in accordance with the amount of axial movement of the shoe 19,
The reaction force of this deflection becomes a force that presses the brake wheel 8'', and the two shafts to be braked are strongly braked.

Here, if the brake wheel 8 is pressed too much, the braking force becomes larger than necessary, and a large torsional force is generated on the braked shaft 2A, which may result in damage to the braked shaft 2A.

In order to prevent this, a protrusion 19D is formed on the outer circumference of the flange 19C of the brake shoe 19, and a protrusion 19D is formed to protrude outward from the inner circumference of the gear case 14 in correspondence with the protrusion 19D. A protrusion 14A is formed.

Therefore, when the brake shoe 19 rotates a predetermined amount, the protruding ridges 19D and 14A collide with each other, and the brake shoe 19 does not rotate any further.

That is, since the brake shoe 19 does not move further in the axial direction and the brake wheel 8 is not pressed, it is possible to prevent excessive braking force from being applied to the braked shaft 2kl.

However, just like this, the same protruding mountain portion 19D.

14A and collide them to form brake shoe 1.
If you just stop the rotation of 9, the stopping position is fixed, so you can only obtain a constant braking force determined by this stopping position.If the required braking force is different for each capacity like a hoist, the required braking force will be different for each capacity. However, there is an inconvenience in that a brake device must be designed accordingly.

Therefore, the brake cover 13 supporting the brake shoe 19 as described above is attached to the gear case 14 in which the stopper protrusion 14A is formed so that its rotational position can be adjusted.

With this configuration, the brake cover 13 is positioned in the direction of rotation of the brake shoe 19. ■Based on the stop position mentioned above,
Since its rotational position can be freely adjusted and assembled, the axial movement reference position of the brake shoe 19 relative to the brake wheel 8 can be adjusted to adjust the axial stopping position of the brake shoe 19. becomes.

In other words, since the amount of deflection of the disc spring 18 can be set freely, the necessary braking force corresponding to each capacity of the hoist can be obtained with the same brake device.

As described above, the brake device according to the above proposal can prevent excessive braking force from being applied to the braked shaft, prevent the risk of damage to the shaft, and improve safety. With the same brake device, each braking force can be set according to each model, each capacity, etc.

However, in order to convert the rotation of the brake shoe 19 into the amount of axial movement, a screw is provided on the outer circumferential surface of the cylindrical portion 19A of the brake shoe 19 and the inner circumferential surface of the brake cover 13 so that they are screwed together. Not only is it not possible to adopt a stacking system with a good stacking system, but also the center of the brake shoe 19 fluctuates, making it impossible to maintain a constant distance between the inner circumferential surface of the brake shoe 19 and each of the distance pieces 10A to 10C.

In addition, since it is difficult to accurately machine the starting position of the thread, it is necessary to adjust the mounting position of the brake cover 13 in order to set the amount of axial movement of the brake shoe 19. There is a processing limit to changing the thread pitch, and it is impossible to optimize the amount of axial movement of the brake shoe 19 relative to the rotation angle of the brake shoe 19.

The present invention has been made in view of this point, and its purpose is to
It has excellent assembly workability and is ideal for use with brake shoes, etc.
The object of the present invention is to provide a brake device in which the center of a braking member can be easily set and the braking force can be easily set to an optimum value.

In order to achieve this object, the present invention provides a first braking member such as a brake shoe, a cylindrical part integrally formed by pressing a steel plate, and a flange part having an inclined surface extending in the circumferential direction. A supporting member such as a brake cover is similarly constructed from a cylindrical part integrally formed by pressing a steel plate and a flange having an inclined surface extending in the circumferential direction, The cylindrical portion of the first braking member is fitted inside the cylindrical portion of the supporting member, and the inclined surfaces of the first braking member and the supporting member are brought into contact with each other.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. FIG. 6 is a longitudinal sectional side view of a safety brake according to an embodiment of the present invention, and FIG. 7 is a perspective view of the brake shoe. The same reference numerals as in FIGS. 1 to 5 indicate the same or equivalent parts.

This embodiment differs from the brake device according to the above proposal mainly in the configurations of the brake cover 13 and brake shoes 19.

That is, the brake shoe 19 has a bottomed cylindrical shape consisting of a cylindrical portion 19A integrally formed by pressing a steel plate and an open end flange 19C, as shown in FIG. One outer circumferential surface of the shaped portion 19A is not provided with a screw, and instead, an inclined surface 19E is provided on the inner circumferential side of the flange portion 19C to protrude toward the brake cover 13 side and extend at an inclination in the circumferential direction. are integrally press-molded.

Similarly, the brake cover 13 has a cylindrical portion 13A and a flange portion 13B integrally formed by pressing a steel plate.
The inner circumferential surface of the knotted portion 13A is not provided with a screw, and instead, the inner circumferential portion l of the collar portion 13B is
An inclined surface 13C extending obliquely in the circumferential direction, similar to the inclined surface 19E of the brake shoe 19, is integrally press-molded to protrude toward the flange 19C side of the brake shoe 19.

The brake shoe 19 formed in this manner is supported by fitting the smooth outer cylindrical surface of the cylindrical portion 19A to the smooth inner cylindrical surface of the cylindrical portion 13A of the brake cover 13, and Surface 19E is brake cover 13
Therefore, the rotational speed of the motor shaft 2A reaches a critical speed, and the centrifugal pieces 10A to 10C fly outward, causing the cylindrical portion 19A of the brake shoe 19 to When it comes into contact with the inner peripheral surface of the brake shoe 19, the brake shoe 19 is dragged by the centrifugal pieces 10A to 10C and rotates, and due to the action of the inclined surface 13C of the brake cover 13 and the inclined surface 19E of the brake shoe 19, it is rotated in the axial direction, that is, in the direction of the brake wheel 8. , and perform the same braking action as described above.

In this embodiment, since the cylindrical portion 19A of the brake shoe 19 and the cylindrical portion 13A of the brake cover 13 are only fitted with each other with smooth cylindrical surfaces, it is possible to assemble them in a stacked manner. In addition to improving workability, the center of the brake shoe 19 can be easily pulled out compared to the case where the brake shoe 19 is screwed together, and the inner peripheral surface of the brake shoe 19 and the centrifugal piece 10 can be easily removed.
The gap between A to 10C can always be kept constant.

In addition, since the inclined surfaces 19E and 13C of the brake shoes 19 and the brake cover 13 are formed by press working, the inclined surfaces can be accurately positioned relative to the gear case 14, and the braking force during safe braking can be easily adjusted to the optimum value. 1 can be set.

Furthermore, since each of the inclined surfaces 19E and 13C is processed by press processing, the workability is good, and the angle of inclination, the area of the inclined surface, the number of inclined surfaces, etc. can be freely selected, and the brake suitable for the safety brake can be used. characteristics can be easily obtained.

As described above, according to the present invention, it is possible to improve the assembly workability, and also to maintain the center of the first braking member such as the brake shoe always accurately, thereby obtaining stable braking force.

In addition, since each inclined surface of the first braking member and the support member is formed by press working, the positioning of the inclined surface is accurate, and the braking force can be easily set to the optimum value. The properties are also improved.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view of a hoist to which a previously proposed brake device is applied, Fig. 2 is a longitudinal cross-sectional view of a safety brake according to an existing proposal, and Fig. 3 is a cross-sectional view taken along line AA in Fig. 2. Figure 4 is the second
FIG. 5 is a front view showing the non-operating state of the centrifugal unit in the safety brake shown in the figure, FIG. 5 is a front view showing the operating state of the centrifugal unit, and FIG. 6 is an embodiment of the safety brake according to the present invention. FIG. 7 is a perspective view of the brake shoe. 2A...Electric motor shaft, 8...Brake wheel, 10A-10C...Centrifugal piece, 13...
... Brake cover, 13A ... Cylindrical part,
13B...Brim part, 13C...Slanted surface,
19... Brake shoe, 19A...
Cylindrical part, 19C... Flange part, 19E...
Slope.

Claims (1)

[Claims] 1. A braked shaft, a movable member that rotates together with the braked shaft and when the rotational speed reaches a predetermined number of rotations or more, the movable member jumps out in the outer circumferential direction due to the force. (When it pops out, it engages with this movable member and rotates. (A first braking member that moves in the axial direction and a support member that supports this first braking member so that it can freely rotate and move in the axial direction.) , a second braking member attached to the braked shaft so as to rotate together with the braked shaft, and pressing the first braking member against the second braking member by moving the first braking member in the axial direction. In the brake device configured to brake the rotation of the braked shaft, the first braking member is integrally formed by pressing a steel plate into a cylindrical portion and a flange portion having an inclined surface extending in a circumferential direction. The supporting member is also composed of a cylindrical part integrally formed by pressing a steel plate and a flange having an inclined surface extending in the circumferential direction, and the cylindrical part of the supporting member A braking device characterized in that a cylindrical portion of the first braking member is fitted inside the cylindrical portion of the braking device, and the inclined surfaces of the first braking member and the supporting member are brought into contact and engaged with each other.