JPH0362638B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides an operating device for an electric chain block that allows a worker to hoist or lower a heavy object as if he were lifting it or lowering it himself by moving a movable grip up and down. It is related to.

[Prior art]

In an electric chain block for hoisting and lowering heavy objects, in order to facilitate operation, the operator moves the movable grip up and down, allowing the operator to hoist and lower the heavy object as if he were lifting it himself. An electric chain block operating device has been developed that allows the operation of electric chain blocks.

Figure 6 is a diagram developed by the present applicant and applied for a patent (Patent Application
62-225948) is a sectional view showing a main part of an operating device for an electric chain block. In the figure, 61 is a cylindrical body that is engaged between the tip of a hoisting and lifting chain (not shown) and a load hanging hook (not shown), and the outer periphery of the cylindrical body 61 is is provided with a cylindrical movable grip 62 that moves up and down a predetermined amount, and furthermore, limit switches 63 and 64 are provided inside the cylindrical body 61, and the limit switches 63 and 64 are switches that move in conjunction with the movable grip 62. It is designed to be operated by a contact member 65. That is, by moving the movable grip 62 upward, the limit switch 63 is turned on, and by moving it downward, the limit switch 63 is turned on.
4 is now turned on. Note that 66 is a torsion spring that urges the movable grip 62 to the neutral position.

In the operating device having the above configuration, the movable grip 6
When the movable grip 62 is moved upward, the limit switch 63 is actuated, and a control circuit (not shown) is actuated to rotate the drive motor in the forward direction to wind up the chain for winding up and down.When the movable grip 62 is moved downward, the limit switch 64 is actuated and the drive motor is reversed. Rotate to lower the hoisting chain.

[Problem that the invention seeks to solve]

Although the operating device with the above configuration has the excellent advantage that the operator can operate it as if he or she were lifting or lowering a heavy object, the movable grip 62 can be moved upward or downward. When hoisting and lowering is performed by operating downward, if the vertical movement speed of the hoisting and lowering chain is faster than the operating speed of the movable grip 62, the drive motor will repeatedly start and stop, causing the hoisting and lowering chain to wind. There was a drawback that lifting and lowering could not be carried out smoothly. For example, when the operator moves the movable grip 62 upward to perform a hoisting operation, the drive motor immediately rotates in the forward direction, and the chain for hoisting and lowering rapidly winds up, causing the movable grip 62 to move relatively downward. As a result, the limit switch 63 is turned OFF and the drive motor is stopped. When the drive motor stops and the hoisting chain for lifting and lowering stops, the movable grip 62
moves up and limit switch 63 turns on again.
The drive motor immediately rotates in the forward direction. This causes the drive motor to start and stop repeatedly. This may also occur when the movable grip 62 is lowered to perform a lowering operation. That is, when the grip 12 is operated upward or downward, there is a problem in that chattering occurs when the winding/up/down chain ascends or descends.

The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide an operating device for an electric chain block which eliminates the above-mentioned problems and allows smooth hoisting and lowering by vertically moving a movable grip.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides a cylindrical body engaged between the tip of a hoisting and lifting chain and a load suspension hook, and an outer periphery of the cylindrical body. a cylindrical movable grip that fits into the grip and slides up and down a predetermined amount; and first and second upward movement detectors that are comprised of a limit switch and the like that operate according to the amount of upward movement of the movable grip;
The grip is equipped with first and second downward motion detectors which are also configured with a limit switch, etc., which operate according to the amount of downward movement of the movable grip, and when the movable grip moves upward, the first and second upward motion detectors When activated, the drive motor is rotated in the forward direction to wind up the hoisting/lowering chain, and the hoisting is continued even if the second up-motion detector becomes inactive, and both the first and second up-motion detectors are activated. When it becomes inactive, the drive motor is stopped to stop hoisting, and when the movable grip moves downward, when the first and second downward movement detectors are activated, the drive motor is reversely rotated to lower the hoisting and up-down chain. At the same time, even if the second lowering motion detector becomes inoperative, the lowering continues, and when both the first and second lowering motion detectors become inoperative, the drive motor is stopped and the lowering is stopped. The present invention is characterized in that it is provided with a control circuit that causes the

[Effect]

By configuring the operating device of the electric chain block as described above, so-called two-stage detection is achieved in which upward movement detection and downward movement detection are comprised of first and second detectors that operate in accordance with the amount of movement of the movable grip, respectively. The structure is such that the initial operation of hoisting and lowering does not operate unless the first and second detectors are activated, and after moving to the hoisting or lowering operation,
Even if the second up-motion detector or down-motion detector becomes inoperable, the hoisting or lowering operation will not be stopped unless the first up-motion detector or down-motion detector becomes inoperable. Therefore, when the winding chain is raised or lowered by the vertical movement of the movable grip, so-called chattering does not occur.
Winding up and down becomes smooth.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a diagram showing the main parts of an operating device for an electric chain block according to the present invention, and FIG. 1a is a front view;
FIG. 1b is a sectional view taken along the line A--A in FIG. 1a. 2 is a cross-sectional view taken along the line B--B in FIG. 1b, and FIG. 3 is a cross-sectional view taken along the line C--C in FIG. 1a. In the figure, 11 is a cylindrical body, a hanging hook is attached to the cylindrical body 11 and the lower end as will be described later, and a protrusion at the upper end engages with the tips of a pair of winding and lifting chains. A flange 14 on which a flange 14a stands is attached. A fixed grip 13 is fixed to the lower part of the cylindrical body 11 with screws 13a. A movable grip 12 that slides up and down on the outer periphery of the cylindrical body 11 is provided above the fixed grip 13.

A limit switch mounting base 31 is provided inside the range in which the cylinder body 11 and the substantially movable grip 12 move up and down, and the limit switch mounting base 31 has four limit switches 17, 18, 19, 20.
is attached. In addition, the limit switch mounting base 31 has two elongated holes 31 vertically located above and below.
a, 31b are formed, and these elongated holes 31a, 31b
Two vertical elongated holes 26, 26, 27, and 27 are also formed in the cylindrical body 11 at positions corresponding to the cylindrical body 11 so as to face each other.

The limit switch 17 and the limit switch 18 are arranged opposite to each other across the elongated hole 31a in the upper part of the limit switch mounting base 31.
Further, the limit switch 19 and the limit switch 20 are arranged opposite to each other across the elongated hole 31b at the bottom of the limit switch mounting base 31. Also, limit switch 18 is limit switch 1
The limit switch 20 is mounted a predetermined dimension above the limit switch 19, and the limit switch 20 is mounted a predetermined dimension below the limit switch 19. That is, as will be described later, the limit switch 17 constitutes a first upward motion detector that is activated when the movable grip 12 moves above a predetermined amount, and the limit switch 18 constitutes a second upward motion detector that is activated when the movable grip 12 moves above a predetermined amount. Configure a vertical motion detector. Also, limit switch 19
constitutes a first downward motion detector which is activated when the movable grip 12 moves downwards by a predetermined amount, and limit switch 18 constitutes a second downward motion detector which is activated when the movable grip 12 moves downwardly by a predetermined amount. do.

A rod member 21 is disposed passing through the long holes 26, 26 of the cylinder body 11 and the long hole 31a of the limit switch mounting base 31, and the rod member 21 is arranged to pass through the long holes 26, 26 of the cylinder body 11 and the long hole 31a of the limit switch mounting base 31. The rod member 22 is arranged to pass through the hole 31b. Further, a spring hook member 23 and a spring hook member 2 are provided at respective predetermined positions of the bar member 21 and the bar member 22.
4 is fixed, and both ends of a spring 25 are engaged with the spring hanging members 23 and 24, thereby urging the rod members 21 and 22 in a direction toward each other. . Inside the movable grip 12 are longitudinal long grooves 12a, 12b, 12 into which the head portions at both ends of the rod member 22 of the rod member 21 are inserted.
c, 12d are provided.

When the movable grip 12 is moved upward, the head portions at both ends of the bar member 21 come into contact with the lower portions of the long grooves 12a and 12b and move upward against the elasticity of the spring 25. At this time, the long grooves 12c and 12d move upward along the head portions at both ends of the rod member 22, which does not move. By this upward movement of the rod member 21, the operating levers of the limit switch 17 and the limit switch 18, which are arranged opposite to each other, are moved to the operating lever 1.
7a, the operating lever 18a are pressed in this order, and the limit switch 17 and limit switch 18 are turned on in that order.
becomes. When the movable grip 12 is released, the rod member 21 and the movable grip 12 are returned to the neutral position by the spring 25. Furthermore, when the movable grip 12 is moved downward, both ends of the rod member 22 are moved into the long grooves 2.
1c, 12d and moves downward against the elasticity of the spring 25. By this downward movement of the rod member 22, the operating levers of the limit switch 19 and the limit switch 20, which are arranged opposite to each other, are changed to the operating lever 19a and the operating lever 20.
A is pressed in that order, and limit switch 19 and limit switch 20 are turned on in that order. By releasing the movable grip 12, the movable grip 12 and the rod member 22 return to their neutral positions.

FIG. 4 is a circuit diagram showing the configuration of the control circuit of the electric chain block operating device according to the present invention.
In the figure, RST is a three-phase AC power supply, 17b is a normally open contact of the limit switch 17, 18b is a normally open contact with the limit switch 18, 19b is a normally open contact of the limit switch 19, 20b is a normally open contact of the limit switch 20, 28 , 29 are electromagnetic switches, 28a and 28b are normally open contacts of the electromagnetic switch 28, and 29a and 29b are normally open contacts of the electromagnetic switch 29, respectively.

In the electric chain block operating device that includes the main parts of the operating device and the control circuit, when the movable grip 12 is grasped by hand and moved upward, the rod member 2
1 rises against the elasticity of the spring 25, the limit switch 17 and the limit switch 18 operate in sequence to turn on their normally open contacts 17b and 18b, and the electromagnetic switch 28 operates to close their normally open contacts 28a and 28b. close. As a result, the drive motor 30 rotates in the forward direction, and the hoisting/up-winding chain is immediately hoisted. As a result of this winding up, the cylinder 11 immediately rises and the movable grip 12 descends relatively, turning the limit switch 18 OFF and its normally open contact 18b turned OFF, but the normally open contact of the electromagnetic switch 28 Since 28a is ON, electromagnetic switch 2
8 continues to operate, the drive motor 30 continues to rotate in the forward direction, and the hoisting chain continues to be hoisted. That is, even if the second limit switch 18 disposed at the top is turned OFF due to the relative descent of the movable grip 12 due to the winding up and down chain,
The drive motor 30 does not stop until the first limit switch 17 located at the bottom thereof is turned off. Furthermore, when the movable grip 12 is moved downward, the bar member 22 descends against the elasticity of the spring 25, and the limit switch 19 and the limit switch 20 are operated in sequence, and their normally open contacts 19b and 20 are operated in sequence.
b is turned on, the electromagnetic switch 29 operates, and its normally open contacts 29a and 29b are closed. As a result, the drive motor 30 rotates in the reverse direction, and the hoisting and lowering chains are immediately hoisted down. As a result of this lowering, the cylinder 11 immediately descends and the movable grip 12 rises relatively, turning the limit switch 20 OFF and its normally open contact 20b turned OFF, but the electromagnetic switch 29 Since the contact 29a is ON, the electromagnetic switch 29 continues to operate, the drive motor 30 continues to rotate in reverse, and the hoisting chain continues to be hoisted. That is, due to the relative lowering of the movable grip 12 due to lowering of the winding/up/down chain, the second limit switch 20 disposed at the bottom is moved.
Even when the drive motor 30 is turned off, the drive motor 30 does not stop until the first limit switch 19 disposed above it is turned off.

As mentioned above, the drive motor 30 does not stop immediately due to the vertical movement of the movable grip 12 when the hoisting/lowering chain is raised or lowered. The so-called chattering phenomenon does not occur, and smooth operation of hoisting and lowering is possible.

FIG. 5 is a diagram showing the overall structure of an electric chain block equipped with an operating device having the above-mentioned structure, in which FIG. 5A is a front view and FIG. 5B is a side view. A load hanging hook 32 is attached to the lower end of the cylindrical body 11, and the lower end of the hoisting and lifting chain 36 is fixed to the projections 14a, 14a of the flange 14 as described above. Note that 33 is a drive unit including the drive motor 30 and the like, and 34 is a block hanging hook for suspending the electric chain block.

In the above embodiment, the first and second grips are operated in accordance with the amount of upward or downward movement of the movable grip 12.
limit switch 17,
19 and limit switches 18 and 20, but the detector is not limited to the limit switch. For example, it may include a light emitting source and a light receiver, and when the movable grip 12 moves a predetermined amount, the light emitted from the light emitting source is detected. The detector may be configured to receive the light with a light receiver; in short, any detector may be used as long as it is configured to detect the amount of vertical movement of the movable grip 12 in two stages. Of course.

〔Effect of the invention〕

As explained above, according to the present invention, the upward movement detector and the downward movement detection have a so-called two-stage detection configuration consisting of the first and second detectors, each of which operates according to the amount of movement of the movable grip. Therefore, the initial operation of hoisting and lowering will not operate unless the first and second detectors are activated, and after moving to the hoisting or lowering operation, even if the second up-motion detector or Even if the lower movement detector becomes inoperative, the hoisting or lowering operation is controlled so as not to stop unless the first upward movement detector or lower movement detector becomes inoperable. An excellent effect can be obtained in that smooth hoisting and lowering operations are possible through dynamic operation.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the main parts of an operating device for an electric chain block according to the present invention, and FIG. 1a is a front view;
Figure 1b is a cross-sectional view taken along the line A-A in Figure 1a;
The figure is a cross-sectional view taken along the line B-B in FIG. 1b, FIG. 3 is a cross-sectional view taken along the line C-C in FIG. 1a, and FIG. FIG. 5 is a circuit diagram showing the configuration of the circuit. FIG. 5 is a diagram showing the overall configuration of an electric chain block equipped with the operating device configured as described above. FIG. 5A is a front view, FIG. 6B is a side view, and FIG. FIG. 2 is a cross-sectional view showing the main parts of the operating device for the electric chain block of FIG. In the figure, 11...cylindrical body, 12...movable grip,
13... fixed grip, 14... flange, 1
7, 18, 19, 20...Limit switch, 2
1, 22... Bar member, 23, 24... Spring hanging member, 25... Spring, 26, 27... Long hole, 28,
29... Electromagnetic switch, 30... Drive motor, 31
...Limit switch mounting base.

Claims (1)

[Scope of Claims] 1. A cylindrical body engaged between the tip of the winding/up/down chain and the load hanging hook, and a cylindrical body that fits on the outer periphery of the cylindrical body and slides up and down a predetermined amount. movable grip,
A first actuator that operates according to the amount of upward movement of the movable grip.
and a second upward movement detector, and first and second downward movement detectors that operate according to the amount of downward movement of the movable grip, and when the movable grip moves upward, the When the upper movement detector is activated, the drive motor is rotated in the forward direction to hoist the hoisting and lowering chain, and the hoisting is continued even if the second upper movement detector is inoperative, and the first and second upper When none of the motion detectors becomes inoperative, the drive motor is stopped to stop hoisting, and when the movable grip is moved downward, when the first and second downward motion detectors are activated, the drive motor is reversed. The hoisting chain is rotated to lower the hoisting chain, and even if the second lowering detector becomes inactive, the lowering is continued, and when both the first and second lowering detectors become inactive, the hoisting is started. An operating device for an electric chain block, characterized in that it is provided with a control circuit that stops hoisting by stopping a motor. 2 the first and second upward motion detectors and the first
and a second downward movement detector is disposed inside the cylindrical body and is composed of four limit switches that are turned on and off by the vertical movement of the movable grip. Electric chain block operating device.