JPH024518B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electric chain block equipped with a mechanical brake in a gear reduction section.

[Prior art]

Conventionally, as an electric chain block equipped with a mechanical brake, as disclosed in Japanese Patent Publication No. 54-38378, a drive gear is integrally provided on a drive shaft connected to the rotating shaft of an electric motor, and a hollow A driven shaft is rotatably fitted, a load sheave is provided on the hollow driven shaft, and a torque limiter having an annular driven gear and a mechanical brake are arranged in series, and the intermediate driven shaft is arranged parallel to the drive shaft. , a structure is known in which an intermediate driven gear and an intermediate drive gear are provided that mesh with the drive gear, and the intermediate drive gear meshes with the driven gear.

However, in the case of the above-mentioned conventional electric chain block, the mechanical brake may not operate when there is no load or an extremely small load is applied, so if an electric motor without a brake device is used, Even when the electric motor is stopped under no load or light load, the rotating part of the electric chain block rotates due to inertia and stops the load hanging hook supported by the load chain at the desired level. The problem is that I can't.

Electric chain blocks that use an electric motor with a built-in brake are also known in order to prevent rotation due to inertia when the motor stops operating under no load or at extremely low loads. Since the electric chain block is large in size and expensive, there is a problem that the electric chain block becomes large and expensive.

[Purpose and structure of the invention]

The object of the present invention is to provide an electric chain block that can advantageously solve the above-mentioned problems. A driving gear 4 is provided between the driven shaft 6 that drives the load sheave 5 and the driving gear 4.
In an electric chain block in which a gear reduction device is interposed, which has a driven gear 7 that meshes with the gearbox 7 and a mechanical brake, light braking is always applied between the end of the drive shaft 3 opposite to the electric motor 1 and the gearbox 8. The electric chain block is characterized by being equipped with a brake device 9.

〔Example〕

Next, the present invention will be explained in detail using illustrated examples.

1 to 5 show an embodiment of the present invention, in which one end of a drive shaft 3 is connected to a rotating shaft 2 of an electric motor 1 via a coupling 10, and the other end of the drive shaft 3 is connected to a rotating shaft 2 of an electric motor 1. The end portion is supported by a gearbox 8 made of steel or aluminum via a bearing 11, and a small-diameter drive gear 4 is formed in the middle of the drive shaft 3. The square hole of the steel light braking brake disc 12 is fitted into the square shaft part provided in the part,
A brake disc 12 for light braking is operated by a nut 14 screwed into a threaded rod 13 connected to the end of the drive shaft 3.
is fixed to the drive shaft 3.

A friction plate 16 that contacts the brake receiver 15 on the outer surface of the gearbox 8 is fixed to the brake disc 12 with an adhesive or the like, and the friction plate 16 is attached to the brake receiver between the drive gear 4 and the bearing 11. A light braking spring 17 made of a helical spring for lightly pressing the portion 15 is interposed between the light braking brake disc 12 having the friction plate 16 and the gear box 8.
The brake receiving portion 15 and the light braking spring 17 constitute a constant light braking brake device 9.

An oil seal ring 18 is interposed between the bearing 11 and the brake disc 12 between the drive shaft 3 and the gearbox 8, and the coupling 10 is supported by the gearbox 8 via a bearing 19. and cup ring 10
An oil seal ring 20 is interposed between the drive shaft 3 and the gearbox 8.

A load sheave 5 around which a load chain 21 is wound is integrally provided at one end of a driven shaft 6 arranged parallel to the drive shaft 3, and one end and the other end of the driven shaft 6 are connected to each other by a gear box 8. 22,2
A steel bearing ring 24 which is supported through the load sheave 3 and fitted onto the driven shaft 6 is engaged with the end of the load sheave 5. A steel press ring 25 that engages with a bearing 23 is slidably fitted on the other end of the driven shaft 6, and the support ring 24 has a center hole of a support member 26 made of a spring steel disc spring. A center hole of a pressing member 27 made of a disc spring made of spring steel is fitted and locked into the pressing ring 25.

A steel cam holding part 28 is rotatably and slidably fitted in the intermediate part of the driven shaft 6 between the supporting member 26 and the pressing member 27, and a steel cam holding part 28 is fitted between the cam holding part 28 and the pressing member 27. A press plate 29 made of a steel disc disposed in
is fitted to the driven shaft 6 so as to be slidable and non-rotatable, and a brake pawl 31 is rotatably fitted to the boss of the brake receiver 30 via a cylindrical bearing 32. Brake ratchet wheel 3
The brake pawl 33 that engages with the brake pawl 31 is pivotally connected to the gear box 8, and a spring (not shown) that acts to engage the brake pawl 31 with the brake pawl 31 is engaged with the brake pawl 33. It has been stopped.

The drive gear 4 is attached to the outer periphery of the cam holding portion 28.
A driven gear 7 that meshes with the brake pawl 31 is fitted in a slidable but unrotatable manner, and friction plates 34 and 35 are fixed to both sides of the driven gear 7 by adhesive or welding. Brake receiver plate 30
The friction plate 36 disposed between the flange of A plurality of cam grooves 3 having an inclined bottom surface whose depth changes along
7 are provided at intervals in the circumferential direction of the intermediate shaft, and a brake relaxing cam member 38 made of a steel ball is fitted into the cam groove 37, and a cam holding portion 28
A plurality of recesses 3 are provided on the side of the presser plate 29.
9 are provided at intervals in the circumferential direction of the intermediate shaft, and a steel sphere 40 is fitted into the recess 39 .

One end of the steel pressing collar 41 fitted to the other end of the driven shaft 6 is engaged with the bearing 23, and an oil seal ring is provided between the collar 41 and the bearing fitting part of the gearbox 8. 42 is fitted, an O-ring 43 is fitted into an annular groove provided on the driven shaft 6 inside the collar 41, and a male threaded portion 44 provided at the other end of the driven shaft 6 extends outward from the gearbox 8. An adjustment nut 45 that is projected and screwed onto the male threaded portion 44 on the outside of the gearbox 8 is engaged with the other end of the collar 41.
The tightening force of the adjusting nut 45 causes the collar 4 to
1. The central part of the pressing member 27 is pressed through the bearing 23 and the pressing ring 25, and the flange of the holding plate 29, the driven gear 7, the brake pawl 31, and the brake receiving plate 30 is pressed by the supporting member 26 and the pressing member 27. and friction plates 34, 3 interposed between them.
5 and 36 are tightened.

The pressing member 27 and the supporting member 26 that are tightened by the adjusting nut 45, the driven gear 7 interposed between them, the holding plate 29, the brake receiving plate 30,
Brake ratchet wheel 31 and friction plates 34, 35, 3
6 constitutes a torque limiter, and is gripped by the support member 26 and the pressing member 27 via the holding plate 29, the brake receiving plate 30, the driven gear 7, and each friction plate; A mechanical brake for preventing suspended loads from falling is constituted by a brake claw piece 33 that engages with the brake claw piece 33, a cam holding portion 28 having a cam groove 37, and a brake release cam member 38 fitted into the cam groove 37. .

When adjusting the transmission torque of the torque limiter after assembling the electric chain block, simply connect the part of the constant light braking device 9 protruding outside the gearbox 8 and the transmission torque adjustment part without disassembling the gear reduction device. This can be done by removing the cover 46 covering the gearbox and rotating the adjusting nut 45 outside the gearbox.

Next, the operation of the electric chain block of the above embodiment will be explained.

When the motor 1 of the electric chain block is operated in a no-load state or a light load state, and then the motor 1 is stopped, light braking by the light braking device 9 is always applied to the drive shaft 4, so that the electric Rotation due to inertia of the rotating parts of the chain block is prevented, and therefore, the vertical movement of the load hanging hook supported by the load chain 21 is stopped at the same time as the electric motor 1 stops operating.

With the load hanging on the hook, the electric motor 1
When the drive shaft 3 is rotated in the winding direction, the drive gear 4 rotates the cam holding portion 28 via the driven gear 7.
is rotated, and the direction of rotation is indicated by arrow A in Figure 4.
Since the brake release cam member 38 is located at a deep position in the cam groove 37, the driven gear 7, the presser plate 29, and the brake pawl 31
and brake receiving plate 30 and each friction plate 34, 35,
36 is tightened with a preset tightening force, the rotation of the driven gear 7 is transmitted to the driven shaft 6 and load sheave 5 via the holding plate 29 and brake receiving plate 30, and within the torque range set by the torque limiter. Hoisting operation is carried out inside.

Next, when the drive shaft 3 is rotated in the downward direction by the electric motor 1, the cam holding part 28 is rotated in the reverse direction by the drive gear 4 via the driven gear 7, that is, the arrow B in FIG.
Since the brake release cam member 38 is rotated in the direction, the brake release cam member 38 is moved to a shallow position in the cam groove 37,
As the amount of protrusion of the brake release cam member 38 from the side surface of the cam holding part 28 increases, as shown in FIG. The mechanical brake is relaxed and
Due to the hanging load, the load sheave 5, driven shaft 6, presser plate 29, and brake receiver plate 30 are rotated faster than the rotational speed of the electric motor 1. However, the rotation tightens the mechanical brake, and by repeating this loosening and tightening, the hoisting operation is performed at a speed close to that of rotation by an electric motor.

When the electric motor 1 is stopped after hoisting or lowering the load to the desired height, the load causes the transmission mechanism to reverse, but this reversal can be achieved by tightening the mechanical brake and unifying it. Subsequent rotation is prevented by the brake pawl piece 33 and the brake pawl wheel 31.

When carrying out this invention, as shown in FIG. 6, the cam holding part 28 may be integrally provided inside the driven gear 7, and the recess 39 and steel ball 40 in the above embodiment may be omitted. Only one of the member 26 and the pressing member 27 may be constituted by a disc spring, and furthermore, a presser plate 29 is arranged between the driven gear 7 having the cam holding portion 28 inside and the supporting member 26. At the same time, a brake receiving plate 30 and a brake pawl 31 may be arranged between the driven gear 7 and the pressing member 27.

As the brake releasing cam member 38, a wedge-shaped shoe having an inclined surface that fits the inclined bottom surface of the cam groove 37 may be used instead of the steel ball. , other springs may be used in place of the disc spring.

〔Effect of the invention〕

According to this invention, the drive gear 4 is provided on the drive shaft 3 connected to the rotating shaft 2 of the electric motor 1, and the drive gear 4 is disposed between the driven shaft 6 that drives the load sheave 5 and the drive gear 4. In an electric chain block in which a gear reduction device is interposed, which has a driven gear 7 meshing with the gearbox 7 and a mechanical brake, a constant light braking brake device 9 is provided between the drive shaft 3 and the gearbox 8. ,
Even if you use an ordinary electric motor 1 that does not have a built-in brake device, the electric motor 1 will not work properly under no load or light load conditions.
When the operation of the electric chain block is stopped, the rotating parts of the electric chain block do not rotate due to inertia, and the load hanging hook supported by the load chain can be accurately stopped at the desired level. Moreover, since the ordinary electric motor 1 can be used, the electric chain block can be manufactured in a small size and at low cost.Furthermore, since the constant light braking brake device 9 is disposed on the opposite side of the electric motor 1 in the gear reduction device, , constant light braking The heat dissipation of the brake device 9 can be improved, and furthermore, since the gear reduction device is equipped with a mechanical brake, even if a load is applied when the operation of the electric motor 1 is stopped, the load will be suppressed. As a result, the rotor of the electric motor is rotated, thereby preventing the cargo from falling.

[Brief explanation of drawings]

Figures 1 to 5 show an embodiment of the present invention, in which Figure 1 is a vertical sectional side view showing a part of an electric chain block, and Figure 2 is an enlarged view of a part of Figure 1. Fig. 3 is a front view showing the sphere and cam holding part provided inside the driven gear, Fig. 4 is a sectional view taken along the line C-C in Fig. 3, and Fig. 5 shows the lowering operation. FIG. 3 is a longitudinal side view showing the state of the torque limiter at the time of the present invention. FIG. 6 is a longitudinal sectional side view showing another example of the torque limiter and mechanical brake portion. In the figure, 1 is an electric motor, 2 is a rotary shaft, 3 is a drive shaft, 4 is a drive gear, 5 is a load sheave, 6 is a driven shaft, 7 is a driven gear, 8 is a gearbox, 9 is a constant light braking device, 11 1 is a bearing, 12 is a brake disc for light braking, 13 is a screw rod, 14 is a nut, 1
5 is a brake receiver, 16 is a friction plate, 17 is a spring for light braking, 18 is an oil seal ring, 21 is a road chain, 24 is a steel support ring, 25 is a steel press ring, 26 is a support member, 27 is a pressing member,
28 is a steel cam holding part, 29 is a presser plate, 30 is a brake receiving plate, 31 is a brake ratchet wheel, 33 is a brake pawl piece, 37 is a cam groove, 38 is a brake release cam member, 41 is made of steel The pressing collar 45 is an adjusting nut.

Claims (1)

[Claims] 1 A drive gear 4 is provided on a drive shaft 3 connected to the rotating shaft 2 of the electric motor 1, and a driven gear 7 that meshes with the drive gear 4 is provided between the driven shaft 6 that drives the load sheave 5 and the drive gear 4. In an electric chain block in which a gear reduction device is interposed, which is equipped with a mechanical brake, the end of the drive shaft 3 opposite to the electric motor 1 and the gear box 8
An electric chain block characterized in that a constant light braking brake device 9 is provided between the chain block and the chain block.