JP2912575B2 - Balancer with anti-bounce function - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a weightless balancer having a jump-preventing function. More specifically, in a factory or a warehouse, a person is relatively heavy with a small force. A gravity-free balancer that can safely, reliably, and smoothly carry out lifting work and transfer work such as moving to a predetermined position while maintaining the load. The present invention relates to a balancer having a jump-prevention function for buffering a sudden impact applied to the balancer when a load is not applied.

[0002]

2. Description of the Related Art As a balancer having a jump preventing function, a balancer as disclosed in Japanese Utility Model Publication No. 61-6074 is already known. The balancer disclosed in the above publication has a pair of upper and lower horizontal arms that are pivotally supported at the pivoting support portion and a vertical arm that is pivotally supported at the distal end, and detects the weight of a heavy object supported by the vertical arm. A weightless cargo handling device provided with a parallelogram equilibrium device capable of moving the heavy object to a predetermined position, wherein a cylinder is attached to the turning support portion, and a pipe rod is connected to a piston of the cylinder. A rod having a base end fixed to the lower part of the cylinder is inserted therein, a bubble plate having a small hole provided at the rod end with a flow control device provided at the distal end of the rod, and opening and closing the small hole of the pubable plate, A spring is urged in a direction to open the small hole, and a sliding range is regulated, and the valve flange is fitted to the rod. A chamber for a fluid product contained which is preventing device jumping weightless type handling machine, characterized in that it has in the pipe rod,
With this jump prevention device, it is possible to prevent the vertical arm from jumping when a heavy object falls during the work.

[0003]

However, in the above-described apparatus for preventing jumping, the piston of the cylinder is provided with a pipe rod, and the movement of the fluid in the pipe rod is restricted to prevent the sudden movement of the piston. The structure of the jump prevention device itself becomes complicated, a dedicated pipe rod is required, and a seal is required to use a liquid such as oil. However, there is a problem that it becomes expensive.

Accordingly, the present invention provides a switch having a sensor function for detecting that a load has dropped from a support member on a support member for supporting a load, and automatically operates a pressure circuit in a control device by the function of the switch. It is an object of the present invention to provide a balancer capable of preventing jumping by setting a no-load balance state, and to solve the above-mentioned problems.

[0005]

The technical solution adopted by the present invention to achieve the above object is a balancer which can move a load in a zero gravity state while balancing the load with a cylinder provided in the balancer. A control device for supplying pressure to the cylinder includes an OR element capable of operating the pressure from the pressure source via a no-load regulator or a load regulator, and the same pressure selected by the OR element from the pressure source into the cylinder. A pilot valve capable of supplying the load regulator, and
A switching valve is provided in a circuit that connects the element and a switch that has a sensor function and a load operation switch that opens a flow path when a load is lifted are provided in a circuit that connects the switching valve and a pressure source. Is applied to the OR element via the load regulator and further to the pilot valve so that the same pressure as the pressure adjusted by the load regulator can be supplied from the pressure source to the cylinder via the pilot valve, The switching valve is a balancer having a jump prevention function, wherein the switching valve is switched only when both the load operation switch and a switch having a sensor function are switched to a state in which a flow path is opened.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of a balancer having a jump prevention function according to the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram of a balancer according to the present embodiment, and FIG. Sectional view of a support member for supporting
3 is a side sectional view of the hoist, FIG. 4 is a sectional view in FIG. 3, and FIG. 5 is a circuit diagram as a control device for realizing a jump prevention function.

In FIG. 1, reference numeral 1 denotes a column, and the column 1 is erected and fixed on a pedestal 2, and an arm 3 is pivotally mounted on the column 1. A rail 3a is formed on the arm 2 along the arm axis direction.
On this rail 3a, trolley wheels 4 of front and rear trolleys 4
a is mounted so as to run freely. In addition, the said arm can also be made a telescopic structure as needed. A first pulley 5 and a second pulley 6 are provided on the front and rear trolleys 4, and a belt or a wire (hereinafter referred to as a rope) 7 having one end fixed to a tip of an arm is firstly moved downward through the second pulley 6. After being drooped into a U-shape,
It is configured to be wound around a hoist drum 17 to be described later via a pulley 5. A moving pulley 8 is supported on the U-shaped portion of the cable, and a load (load) W
Is provided.

The supporting member 9 supports the load,
It has a sensor function (details will be described later) that can detect the state of not being supported, and has a ring 24 that can be detachably attached to the moving pulley 8 as shown in FIG. . A box 25 is fixed to the ring 24, and a guide portion 26 of a shaft, which communicates with the box and extends downward, is provided on the lower surface of the box 25. A load operation switch (hereinafter, toggle switch) 38 and a grip 2
7 are fixed. A shaft 28 is slidably provided on the guide portion 26. A hook 28a is provided at a lower end of the shaft 28, and an operating piece 28b for operating a switch having a sensor function described later is provided at an upper end. I have. A spring 2 that constantly urges the shaft 28 upward in the figure between the operating piece 28b and the bottom surface of the box.
A switch having a sensor function is provided on the bottom surface of the inside of the housing along with a stopper 25a along the outer periphery of the spring 28c, and further, the shaft 28 moves downward to contact the operating piece 28b. (Hereinafter, a limit switch) 29 is provided. The limit switch 29 can detect the suspended state of the load by contacting the operating piece 28b.

Therefore, when the load is not supported by the support member 9, the shaft 28
When the load is hung on the shaft 28, the shaft 28 moves downward against the stopper 25a against the urging force of the spring 28c. At this time, the operating piece 28b that has moved downward is attached to a limit switch 29 provided on the bottom surface of the box.
Are in contact with each other, so that the state of supporting the load can be detected. Further, when the load is the hook 28a
When the load falls, the shaft 28 moves upward by the urging force of the spring 28c, the operating piece 28b separates from the limit switch 29, and it is detected that the load has dropped.
The jump between the moving pulley 8 and the support member 9 is prevented.

A hoist 10 is fixed to the upper portion of the column 1 by appropriate means. The hoist 10 will be described with reference to FIGS. 3 and 4.
A chain pin 12 is fixed to the inner side surface of the first unit 1,
An arc-shaped guide 13 is fixed to the inner upper surface. Further, a bearing 14 is mounted on the side surface of the box, and a shaft 15 is passed through the bearing 14. A sprocket 16 is fixed to the inner end of the shaft 15, and a drum 17 is fixed to the outer side. One end of a rope 7 made of a belt, a wire, or the like is fixed to the drum 17, and the other end of the rope is fixed to the tip of an arm via the above-described front and rear trolley 4.

A cylinder 18 and a chain storage container 19 are attached to the bottom of the box 11, and a balance piston 20 is slidably disposed in the cylinder 18. A sprocket 22 is rotatably mounted on a balance piston 20 in the cylinder 18 via a bracket 21. A chain 23 having one end fixed to the chain pin 12 is wound around the sprocket 22, and the chain 23 is further sprocketed. 22, the sprocket 16 and the other end of the chain
Inside.

The box 11, the cylinder 18, and the chain storage container 19 communicate with each other via the box 11, but the connection portion and the like have a hermetic structure and are airtight chambers. An air supply port (not shown) is provided above the cylinder 18, and a control device for supplying compressed air into the hermetic chamber when lifting a load is mounted on a side of the cylinder 18.

The control device has the circuit configuration shown in FIG.
In the figure, 31 is a pressure source, 32 is a check valve, 33 is a pilot valve, 34 is an OR element, 35 is a switching valve, 3
6 is a no-load regulator, 37 is a load regulator, 3
8 is a toggle switch, 29 is a limit switch having a sensor function, and 39 is a pressure gauge.

The pilot valve 33 has a function of supplying the same pressure from the pressure source 32 to the cylinder 18 when a predetermined pressure is applied from the OR element 34.
The no-load regulator 36 is for manually adjusting the pressure of the compressed air so as to balance to a no-load state, and the load regulator is for manually adjusting the pressure of the compressed air corresponding to the load. is there. The check valve 32, pilot valve 33, OR element 34, switching valve 35, no-load regulator 36, and load regulator 37 constitute a circuit in a circuit box.

The toggle switch 38 and the limit switch 29 are configured as a two-position switching valve. When the toggle switch 38 is turned on, the flow path is opened, and when the load is suspended from the support member 9 described above. The limit switch 29 comes into contact with the operating piece, and is thereby turned on to open the flow path. The toggle switch 38 and the limit switch 29 constitute a circuit in the attachment. In addition, 10a in the figure
Is a muffler attached to the cylinder 18, and the piston 2
The air can be moved in and out of the lower side of the piston by the vertical movement of zero.

Next, the operation of the balancer having the above configuration will be described. First, the no-load regulator 36 is operated to obtain a no-load balance state.
7 is set in advance to a pressure suitable for the load balance state. When the load (luggage) is lifted and moved after such a state, the arm 3 is turned and the trolley 4 is moved right above the load, and the toggle switch 38 is moved.
To open the flow path, and pull the hook 28a downward with the grip 27 of the support member 9 as it is. Then, the cable 7 is pulled and the drum 17 rotates clockwise. As a result, the sprocket 16 rotates clockwise, and the chain 23 is raised. Therefore, the sprocket 22 attached to the balance piston 20 rises while rotating. At this time, since the pressure adjusted by the no-load regulator acts on the cylinder to maintain a balanced state, a simple operation can be performed.

When the support member 9 is pulled down to the lifting position, the hook 28a is hooked on the load, and then the support member 9 is slightly lifted with the grip 27 so that the operation piece 28b abuts and the limit switch 29 is opened. Then, the pressure from the pressure source acts on the switching valve 35 via the toggle switch 38 → the limit switch 29, and when the switching valve 35 is opened, the pressure from the pressure source is changed to the load regulator 37 for which the pressure is set → opened. Switching valve 35 → O
Acts on pilot valve 33 via R element 34.
As a result, in the pilot valve 33, the same pressure as the pressure set by the load regulator 37 is supplied from the pressure source to the hoist. In the hoist 10, the pressure in the chamber above the balance piston 20 rises, and the balance piston 20 in the cylinder 18 is pushed down,
Sprocket 22 rotates clockwise to pull down the chain.
Therefore, the chain 23 moves by rotating the sprocket 16 counterclockwise, and the end of the chain 23 rises in the storage container 19. As the sprocket 16 rotates counterclockwise, the drum 1
7 also rotates counterclockwise, the rope 7 is wound on the drum 17, the hook 28a is raised, and the load is lifted.

In such a state, the air pressure set by the load regulator and the load are balanced, so that the load can be easily moved up and down only by applying a small force to the load. When it has been raised to a desired position, the arm is turned, and / or the front and rear trolleys 4 are moved along the rails 3a. Then, when the grip 27 is moved slightly downward against the lifting force (or lifting force) of the crimper at that time while the load is in contact with the ground, the operation piece 28b and the limit switch 29 are separated from each other to close the flow path, and no load is applied. The balance is set, and the load can be removed from the hook 9.

At this time, if the load is light, the grip 27 can be moved downward by a relatively light force, whereby the limit switch 29 can be easily turned off. However, when the load is heavy, In such a case, it is difficult to move the grip 27 downward with a light force, and in such a case, it is necessary to operate the toggle switch 38 to bring the loadless balance state. As described above, in this example, when the load is light, it is possible to automatically set the no-load balance state by the limit switch 29 having the sensor function only by operating the support member 9, so that the toggle switch is conventionally used. It is possible to reduce the trouble of operating the switch to bring the no-load balance state. On the other hand, in the case of a heavy load, the toggle switch is turned off with the load grounded to bring the load into a no-load balance state, and the load is removed from the support member 9. If the load accidentally falls off the hook during the above operation, the shaft 2
8 rises due to the urging force of the spring 28c, and the limit switch 29 separates from the operating piece, thereby closing the flow path.
As a result, since the switching valve 35 is closed, the pilot valve is in a no-load balance state, so that the support member 9 can be prevented from jumping.

Instead of the balancer using the front and rear trolleys and the hoist, it is also possible to use a balancer having another configuration capable of performing the same function. The rope is not limited to a belt or a wire, and a rope or the like can be used. Wheels such as casters with brakes can be mounted on the pedestal as needed.
It is also possible to adopt a configuration in which the column can be moved up and down as needed. A power type can also be adopted for turning the arm. Furthermore, the present invention may be embodied in various other forms without departing from its spirit or essential characteristics. In addition, the above-described embodiment is merely an example in all aspects, and should not be construed as limiting.

[0021]

As described in detail above, according to the present invention,
Even when a heavy object is accidentally dropped from the support member while the heavy object is being lifted while maintaining a balance by the balancer, the circuit in the control device is operated by the limit switch having the sensor function in the support member. Can be automatically switched to the no-load balance state, so that jumping of the support member can be prevented, and an excellent effect of providing a highly safe balancer can be achieved.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an air balancer as an embodiment.

FIG. 2 is a sectional view of a support member.

FIG. 3 is a side sectional view of a hoist.

FIG. 4 is a sectional view of FIG. 3;

FIG. 5 is a circuit diagram of a control device.

[Explanation of symbols]

Reference Signs List 1 support 2 pedestal 3 arm 4 front and rear trolley 5 first pulley 6 second pulley 7 cable 8 moving pulley 9 support member 10 hoist 17 drum 25 box 26 cylinder 27 grip 28b operating piece 29 limit switch having sensor function (limit switch) ) 31 Pressure source 33 Pilot valve 34 OR element 36 No-load regulator 37 Load regulator 38 Toggle switch

Claims (3)

(57) [Claims] 1. A balancer capable of moving a load in a zero-gravity state while balancing the load with a cylinder provided in the balancer, wherein a control device for supplying pressure to the cylinder includes a non-load regulator for controlling a pressure from a pressure source. Or, an OR element that can operate via a load regulator, and a pilot valve that can supply the same pressure as the pressure selected by the OR element from the pressure source into the cylinder, and connect the load regulator and the OR element. A switching valve is provided in the circuit, and a switch having a sensor function and a load operation switch that opens a flow path when the load is lifted are provided in a circuit connecting the switching valve and the pressure source,
OR the pressure from the pressure source via a load regulator
Acting on the element and further acting on the pilot valve so that the same pressure as the pressure regulated by the load regulator can be supplied from the pressure source to the cylinder via the pilot valve, and the switching valve is provided with the load operation switch and A balancer having a jump prevention function, wherein the switch valve is switched only when both switches having a sensor function are switched to open the flow path. 2. The balancer having a jump prevention function according to claim 1, wherein both the load operation switch and the switch having a sensor function are provided on a support member that supports the load. 3. The support member includes a housing, a shaft slidably provided on the housing, a spring for urging the shaft, and a shaft for moving the shaft against the urging force of the spring. 3. The balancer having a jump-prevention function according to claim 2, wherein the flow path is opened by the switch having the sensor function.