JPS5818320B2 - hoisting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hoisting device, and more particularly to a hoisting/lowering limit mechanism for an electric chain block.

Generally, a hoisting device such as a chain block includes a frame, a sprocket that is rotatably attached to the frame and driven by a drive motor, a chain that is guided by a chain guide and engaged with the sprocket, and a chain that engages with the sprocket while being guided by a chain guide, and the sprocket. a limit lever that is rotatably provided below the chain and is rotated by the chain when the chain is wound and driven to a predetermined position; and a limit that stops the drive motor in response to the rotation of the limit lever. Equipped with a switch.

A limit switch mechanism of such a conventional hoisting device is shown in FIGS. 1 and 2.

That is, 1.2.3 is a frame, and the sprocket 4 is attached to the frames 1 and 3 by bearings 5 and 6.

The sprocket 4 is connected via a gear T to a drive motor (not shown).

8 is attached between frames 1 and 2 with a ceno guide,
Guide so that the cheno 9 engages with the sprocket 4.

Reference numeral 10 denotes a limit lever, which is located below the sprocket 4 and is provided so as to rotate integrally with the shaft 11.

The shaft 11 is rotatably supported by frames 1 and 2,
A return spring 13 is attached to the extended portion of the frame 1 to keep the limit switch 12 and the limit lever 10 horizontal.

The limit lever 10 is attached with chino guide tubes 14 and 15, and the naen 9 going in and out of the sprocket 4 passes through these guide tubes 14 and 15.

16 is a load hanging hook, and 17 is an end holder.

In such a chain block, by driving the sprocket 4, the chain 9 is hoisted up or lowered to move the load lifting hook 16 up and down.

In the normal state, the limit lever 10 is kept horizontal by the return spring 13, but when the cheno 9 is hoisted up too much, the load lifting hook 16 hits the chino guide cylinder 14 and pushes it up.

As a result, the limit lever 10 is rotated clockwise in FIG. 1 against the force of the spring 13, and the limit switch 12 is activated to stop the drive motor.

On the other hand, if the chino 9 is lowered too much, the end engager 17 hits the chino guide cylinder 15 and pushes it up.
The limit lever 10 is turned counterclockwise to activate the limit switch 12 and stop the drive motor.

Such a conventional device ζ has problems in that the return spring mechanism is complicated and the limit switch is mounted far away from the frame, making positioning difficult.

SUMMARY OF THE INVENTION An object of the present invention is to propose a hoisting device equipped with a limit switch mechanism that has a simple return spring mechanism and is easy to assemble.

In the present invention, an elastic body is provided between the limit lever and the fixed part to resist the rotation angle of the limit lever, and the actuator for operating the limit switch is attached to the frame so that it is pushed back by the rotation angle of the limit lever. It is characterized by:

The following will explain the embodiments shown in the drawings.

FIG. 3 is a partially vertical front view of the Cheno block, FIG. 4 is a cross-sectional view taken along IV-IV in FIG. 3, and FIG. 5 is a partially longitudinal rear view.

In each figure, 20.22 is a frame, and a winding member such as a sprocket 24 is rotatably attached to the frame 20.22 by a bearing 26.2B, and is connected to an output shaft 32A of a drive motor 32 via a gear mechanism 30. Ru.

The drive motor 32 has a rotor 32B, a stator 32C, and a housing 32D, and an electromagnetic release brake 34 is provided on the non-output end side of the drive motor 32.

The cable guide, for example, the Cheno guide 36, is the sprocket 24.
A cable such as a cable 38, which is attached between the frames 20 and 22 so as to cover the periphery of the frame 20 and which is guided by the guide 36 and engages the sprocket 24, hangs down through the limit lever 40.

A load hanging hook 42 is attached to one end of the chino 38, and an end engager 44 is attached to the other end.

Next, the limit switch mechanism will be explained with reference to FIGS. 6 to 8. The limit lever 40 is connected to the frame 20,
The frame 20 side edge is bent to stand up along the frame, and this bent upper edge 40A constitutes a suppressing surface.

Between the limit lenomer 40 and the lower end of the naen guide 36, there are cable guide tubes made of rubber, such as cable guide tubes 48 and 50.
is arranged to hold the limit lever 40 horizontally.

When the limit lever 40 is held horizontally, an actuator, for example, a steel ball 54° 55, supported by an actuator guide, for example, a ball guide 52, 53, protrudes slightly above both ends of the upper edge 40A of the limit lever. Pole guides 52,53 are attached to frame 20.

The inside diameter of the hole at the left end of the ball holder of the pole guide 52, 53 is made slightly smaller than the outside diameter of the ball 54, 55, so that the hole will not fall when the balls 54, 55 are pressed from the right side by the leaf spring 56. Make it.

A switch stand 58 is attached to the frame 20 and supports the leaf spring 56 and limit switches 60 and 62.

The leaf spring 56 is attached so as to press the left side of the steel balls 54, 55, and the limit switch 60.62 is attached so as to be activated when the leaf spring 56 is pushed back by the steel balls 54, 55.

64 is a gear case, 66 is a switch cover, 68 is an operation switch, and 70 is a hook for attachment.

FIG. 9 shows an electric circuit, in which the drive motor 32 is connected to power sources R, S, and T via limit switches 60, 62 and an operation switch 68, and the electromagnetic brake 34 is connected in parallel with the drive motor 32.

In the above configuration, by operating the operation switch 68, the drive motor 32 is rotated in the forward or reverse direction.
8. Wind up and lower.

In the normal state, the limit lever 40 is connected to the chino guide cylinder 48.
It is kept in a horizontal state by 50, and the null pole 5
4 and 55 are pushed by the plate spring 56 and protrude inside the frame 20, so that the limit switches 60 and 62 remain closed.

However, when the cheno 38 becomes over-hoisted and the load lifting hook 42 hits the limit lever 40, the limit lever 40 rotates clockwise while compressing the guide tube 48, and the upper edge 40A presses the steel pole 54. , this steel ball 54 is moved back against the leaf spring 56.

The retreat of the steel ball 54 opens the limit switch 60, cuts off power supply to the drive motor 32 and the electromagnetic brake 34, and stops the rotation of the sprocket 24.

After that, if you want to lower the chino 38, use the operation switch 6.
8 is set to "lower", the drive motor 32 and electromagnetic brake 34 are energized via the limit switch 62, the sprocket 24 is reversed, and the chino 38 is lowered.

When the load lifting hook 42 is separated from the limit lever 40, the limit lever 40 returns to its original horizontal state due to the restoring force of the guide cylinder 48, and the steel ball 54 is also pushed out by the return spring 56 to return to the illustrated state and prepare for the next operation.

On the other hand, if Cheno 38 becomes over-lowered, Cheno 3
The end retainer 44 at the rear end of the holder 8 abuts against the limit lever 40, and the limit lever 40 rotates counterclockwise while compressing the guide tube 50.

As a result, the upper edge 40A of the limit lever 40 presses the steel ball 55 to move it backward against the leaf spring 56, opening the limit switch 62 and stopping the drive motor 32.

Therefore, after that, only winding operation is possible.

Then, by setting it in the winding state, the limit lever 40, steel ball 55, leaf spring 56, and limit switch 62 return to their original states.

Depending on the limit switch mechanism as described above,
The structure of the limit lever 40 is simplified because the elastic guide tubes 48 and 50 provided between the limit lever 40 and the naen guide 36 to guide the chenno 38 serve as elastic bodies to keep the limit lever 40 horizontal. be done.

Additionally, since the limit switches 60, 62 are mounted near the frame 20, assembly is simpler and more compact than conventional devices.

Furthermore, since the steel balls 54, 55 (limit switches 60, 62) are provided far away from the center of rotation of the limit lever 40, there is an advantage that the operating point is stabilized.

Although the steel balls 54 and 55 can be changed to actuators other than spherical, spherical is preferable in order to avoid malfunction due to increased frictional resistance.

As described above, according to the present invention, it is possible to provide a hoisting device that has a simple structure, is easy to assemble, and is equipped with a Mitswitch mechanism.

[Brief explanation of the drawing]

1 and 2 are a partially longitudinal side view and a partially longitudinal side view of the limit switch mechanism in a conventional Cheno block, and FIG. 3 is a partially longitudinal front view of the Naen block according to the present invention. The figure is a cross-sectional view taken along ■-IV in FIG. 3, FIG. 5 is a partially longitudinal rear view, FIG. 6 is a longitudinal side view of the girder-mitswitch mechanism, and FIG. 7 is a cross-sectional view taken from FIG. 8 is a cross-sectional view taken along the line ■--■ of FIG. 6, and FIG. 9 is an electrical connection diagram. 20.22... Frame, 24... Sprocket, 30... Gear mechanism, 32...
...Drive motor, 36...Cheno guide, 38
...Cheno, 40...Limit lever,
42---Load hanging hook, 44... End engager, 4B, 50... Cheno guide tube, 52.53.
...Pole guide, 54,55...Steel ball, 60,62...Limit switch.

Claims (1)

[Claims] 1. Frames facing each other, a winding member rotatably mounted between these frames and driven by a drive motor, and the winding member guided by a cable guide also arranged between these frames. A cable is wound around a member, and the cable is located below the winding member, and an intermediate portion of the winding member is pivotally supported by the frame so as to be rotatable; a limit lever for both raising and lowering sides that is rotated by the cable when the cable is wound up; and a limit switch that stops the drive motor in response to the rotation of the limit lever. In the winding device, the limit lever is made of a steel plate having a bent portion that moves along the inner surface of at least one of the frames, and the lever is normally placed between the limit lever and the cover of the winding member. ζ
Two elastic cable guide tubes are provided to maintain the trowel horizontally, the limit switch is attached to the outer surface of the frame on the bending part side, the actuator of the limit switch is housed in this frame, and An actuator guide having an opening with a diameter slightly smaller than that of the actuator is provided, and a spring body is used to guide the actuator into the opening so that a part of the actuator of the limit switch passes through the opening and protrudes inside the frame. When the limit lever is rotated, a bent portion of the limit lever is formed on the actuator, and when the limit lever is rotated in the same direction, the actuator resists the elasticity of the spring body. A hoisting device characterized in that the limit switch is configured to be movable outwardly of the frame, and the limit switch is opened and closed by lateral movement of the actuator.