JPH0780676B2 - Balance hoist - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a balance hoist capable of reducing the burden on the operator and improving the work efficiency in the operation of carrying a large number of relatively heavy objects, and a device for holding the objects. .

[0002]

2. Description of the Related Art Generally, when a small object is to be conveyed, the small object is put in a case or the like to improve the workability of the case. However, this case is conveyed when a cart or cases are stacked. It is carried out by stacking it on a basket car or the like having a basket-like shape so as not to fall down and transporting it, or transferring it to a conveyor. However, loading work such as taking out from a comparatively narrow place where there are obstacles on the side such as stacked cases or basket cars and transferring it to another position is difficult even if it is not very heavy. The larger the load, the heavier the burden on the operator and the risk of an accident.

Further, in the work of carrying a relatively heavy load, there are cases where a hoist is used which can reduce the burden on the worker and improve the working efficiency.
However, in a conventional hoist, for example, a method of winding a wire by a motor, in which the load of the object to be lifted is converted into a voltage by a sensor and the signal of this voltage is used to control the drive speed of the motor that is the control drive means. ,
Since the motor will operate even if the load fluctuates slightly, the operator must perform a fine movement adjustment of the conveyed object by giving the function to lift the conveyed object mainly by the hoist. Since the motor is actuated by the force applied during the fine movement adjustment, the state in which the conveyed object vibrates vertically occurs. Therefore, in the past, in order to suppress this vibration, the sensitivity of the motor itself or the sensor was reduced.

However, as a result of adopting the above-described method of suppressing the vibration by lowering the sensitivity of the drive system in this manner, the performance of the motor is deteriorated and the moving speed due to the driving force of the motor is reduced, and The work speed had to be sacrificed, such as a decrease in the ability to follow motion commands.

[0005]

As described above, in the conventional balance hoist, if the rotation ability of the drive means is improved to improve workability, the load sensor of the drive means causes an excessive hypersensitivity reaction, which causes the operator to feel uncomfortable. Since the desired function cannot be fully exerted, it is necessary to take the extremely passive countermeasures as described above, and there is a limit in simultaneously reducing the burden on the worker and improving the work efficiency.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems, and to provide a balance hoist which does not move up and down, has good operability, and has a high working speed, and a device for gripping a conveyed object.

[0007]

One of the objects of the present invention is to provide a gripping device for catching a conveyed product at the lower end portion of a wire connected to a winding drive means, A balance hoist provided with an operating section for adjusting the drive of the drive means, wherein the winding drive means is composed of a servomotor having a negative actuation brake, and is controlled by a feedback signal of a rotation speed detection sensor,
The operation portion includes an input member elastically held so that it can be reciprocally moved within a certain range by fingers, and is loosely fitted between movement paths of action points formed so as to face the input member. When the positioned output part comes into contact with the action point part, it outputs the drive signal of the servo motor, and when the movement operation of the input part moves more than a certain amount due to the gap between the action point part and the output part. This is achieved by a balance hoist characterized in that it is configured to output the drive signal of the servo motor only.

Another object is a gripping device used for a balance hoist, in which a gripping part main body provided with an operating part is provided with a catching part in which at least two parts project downward.
Each of the capturing parts has a pivoting fulcrum near the lower end of the capturing part, and each locking part is provided so as to project inwardly of the gripping part main body around the fulcrum. At least a part of the upper edge of the capturing part is provided. The engaging portion is engaged below the flange portion with respect to a case having a flange portion configured in a flange shape.
So that the locking part is from above the flange part.
It is rotatable in the direction to enter the lower side and
This is achieved by a gripping device characterized in that it is configured to be locked in a holding position .

That is, by using the servomotor as the driving means of the hoist, the lifting holding force can be provided by the torque when the motor is stopped without using the friction brake, and the operating portion of the drive system has a structure. By using the operation system with play as described above, it is possible to avoid the operation of the drive system due to unexpected contact, impact, vibration, etc., and to use a sensor sensitive to the output section, and to provide a high-performance drive system. Since it can be used, a desired movement can be performed easily and surely, and the work efficiency can be improved and the burden on the worker can be reduced.

Further, the gripping device provided at the tip of the wire of the hoist allows small items or articles which are difficult to hold by hand to be put together and extends downward along the side of the case when holding the case. The capture unit
Since the case does not require a large horizontal space,
When taking out or storing the case from a narrow place, the burden on the operator is reduced, and the workability can be improved.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. However, the present invention is not limited to this embodiment.

The balance hoist in this embodiment is
Jib crane 1 with arm 3 protruding from prop 2
Is attached to. The hoist 4 is attached to the lower part of the arm 3, and the wire 7 is attached by a winding drum 6 connected to a servo motor 5 which is a winding driving means.
Is configured to be wound up, and the lower end portion of the wire 7 is configured to hold a case 20 which is a conveyed object by a gripping device 9
have. The gripping device 9 is provided with an operation unit 10 that outputs a signal of a drive command for the servomotor 5 to move the gripping device 9 up and down.

As shown in FIG. 2, the gripping device 9 has a main body frame 4 having a catching portion 42 whose both end portions project downward.
It is composed of 0s. The tip of a wire 7 connected to the winding drum 6 is connected to the substantially center of the upper portion of the frame 40, and the operation unit 10 for issuing a command to perform an ascending / descending operation around the connection of the wire 7 and described later. A wire driving device (not shown) that operates to release the grip of the case 20, a release switch 47 for operating the wire driving device, and the like are appropriately provided in consideration of weight balance.

The case 20 has a rectangular opening, and a flange portion 20a having a flange-like upper end edge.
The case 20 has a flange portion 20.
The engaging portion 44 of the capturing device 9, which will be described later, is engaged with the lower side of a to be lifted.

Each of the trapping portions 42 has a pivot shaft 44a near the lower end of the trap portion, and pivots with the pivot shaft 44a as a fulcrum so as to project inward of the main body of the gripping device and retract into the trap portion 42. A free locking member 44 is provided. And
As shown in the figure, the locking portion 44 can be configured, for example, such that both ends of the U-shaped frame are penetrated by the rotation support shaft 44a, and the free wire 45 connected to the wire driving device is provided at its free end. The locking portion 44 is connected, and by pulling the opening wire 45, the locking portion 44 operates so as to retract into the frame of the capturing portion 42. The locking portion 44 is biased in the projecting direction (a direction resisting the pulling direction of the opening wire) by a torsion coil spring or the like (not shown) wound around the rotation support shaft 44a. Therefore, the locking portion 4
When the pulling wire 4 is not pulled by the opening wire 45, the tip of the wire 4 projects inward from the frame of the capturing portion 42.

An operation unit 1 for controlling the drive of the servomotor 5
For 0, for example, the structure as shown in FIG. 3 can be adopted in which the operation knob portion is always returned to the center. An important configuration of the operation unit 10 is that even if the sensor provided in the operation unit 10 has extremely high sensitivity and high performance, the sensor reacts due to an unexpected impact or vibration due to this impact. It is in the place that enables accurate operation of the drive unit without.

That is, as shown in FIG. 3, the basic structure of the operating portion 10 is held by a fulcrum 33 and an elastic member 34, and can be reciprocally moved within a certain range around the fulcrum 33 (up and down). Input unit 3 attached so that it can be moved) and is always urged to return to the center.
It has 0. In addition, the power point portion 31 operated by fingers
Two action point portions 32 are formed so as to face each other on a side opposite to each other with a predetermined distance therebetween, and an output portion 35 for outputting a drive signal of the servo motor 5 is provided between the two action point portions 32. Gap 3 above and below (between travel paths)
It is located with nine. The output unit 35 is provided with a sensor such as a strain gauge 36, so that a force is applied to the output unit 35 when the action point portion 32 comes into contact, and a desired output signal can be taken out from the strain gauge 36.

Since the gap 39 between the action point portion 32 and the output portion 35 is formed in this way, even if an unexpected shock or vibration is applied to the input portion 30 and the input portion 30 is slightly moved, this movement will occur. The strain gauge 36 can output an appropriate drive signal for the servomotor 5 only when the movement operation of the input unit 30 moves beyond the gap 39 by a certain amount or more without acting on the output unit 35.

As shown in FIG. 2, for example, in the operating section 10, the force point portion 31 of the input section 30 is actually the handle section 4.
The handle portion 43 can be configured to be close to the handle 3.
You can operate up and down with your fingertips while holding it by hand.

Since the servo motor 5 can generate a constant torque even when the rotation thereof is stopped, the pulling force of the wire 7 is secured and the case 20 is suspended even if there is no holding brake for temporary stop. It is easy to create a lowering balance. In addition, the motor rotation speed can continuously obtain stable torque and rotation speed from zero to the maximum speed, and since speed feedback is applied, the rotation speed can be accurately adjusted only by the instruction voltage of the analog signal from the servo amplifier. The number can be controlled, the response operation by the movement instruction operation is quick, and the vertical movement speed is hardly influenced by the weight of the load (weight of the article in the case). It should be noted that the servo motor 5 is provided with an emergency negative operation brake (friction brake) that acts as a brake when an unexpected situation such as power failure or other abnormality such as power failure occurs, thereby ensuring the safety of transportation work. is doing.

The control unit 12 attached to the support column 2 has a general control function such as activation at the start of work, rough setting suitable for a desired work, or automatic stop in the event of an abnormality.

By using the apparatus constructed as described above, a trolley or a large number of cases 20 stacked in one place
, For example, when carrying out a transfer operation such as sequentially moving on a conveyor, first hold the handle portion 43 of the gripping device 9,
The length of the wire 7 is increased by operating the force point portion 31 of the operating portion 10 so as to push the force point portion 31 downward or upward (the gripping device 9 descends when the force point portion 31 is moved downward, and rises when the force point portion 31 is moved upward). The gripping device 9 can be moved to a desired position by adjusting the height. At this time, as shown in FIG. 4, the direction of the output unit 35 and the speed command signal are input to the servo amplifier 14, and the servo amplifier 14 applies the power supply corresponding to the speed command signal to the servo motor 5, A resolver 15 which is a rotation angle detection sensor, an encoder, or the like is attached to 5 to detect the rotation speed, and this detection signal is fed back to the servo amplifier 14, and a comparator in the servo amplifier 14 compares the detected speed signal with a speed command voltage to The power supply is controlled so as to reduce the difference.

With the operation unit 10 and the drive system configured as described above, the gripping device 9 can be moved with a delicate motion extremely close to the motion of the hand desired by the operator. And
When lifting the case 20, attach the gripping device 9 to the case 20.
After being positioned above, the positioning portions 46 provided on the left and right of the main body frame are lowered so as to abut on the upper edge of the case 20, so that the locking portion 44 rubs down the flange portion 20a of the case 20. Move to flange 2
It goes in so as to engage with the lower side of 0a (Fig. 5). After that, while appropriately operating the operation unit 10, the gripping device 9 is moved and held on the conveyor, and the release switch 47 is pressed, whereby the wire driving device operates and the opening wire 45 is moved upward. When the pull-up locking portion 44 retracts, the grip of the case 20 by the grip device 9 is released (FIG. 6).

The locking of the case 20 by the locking portion 44 is maintained by the torsion coil spring and the weight of the case itself, and is not configured to be maintained by an external electric force. The case will not be released due to an unexpected situation. Further, as described above, the negative operation brake prevents accidental rotation of the servo motor 5 (rotation that lowers the gripping device) when the servo lock is released due to a power failure or the like. There is no danger of falling. Further, by applying the negatively-operated brake at times other than emergency, it is possible to save electricity consumption and prolong the life of the motor.

Although the strain gauge 36 is used as the sensor in the output unit 35 of the operation unit 10 in the above-described embodiment, the present invention is not limited to this, and various sensors such as electromagnetic type and electrostatic capacitance type are used. be able to. A joystick having a built-in potentiometer (variable resistor) can be used as the output unit 35.

In the above-described embodiment, the positioning portion 46 of the case 20 is provided on the capturing portion 42, but it is not always necessary to provide such positioning means. For example, the capturing portion 42 may be provided on the upper surface of the case 20 at an appropriate position. It is also possible to have a bent structure so that it hits with. Further, the trapping form of the case 20 is not limited to the structure such as the engaging portion 44 provided in the trapping portion 42, and may be suction trapping using a suction plate.

Further, although the structure using the jib crane 1 is adopted in the above-mentioned embodiment, the balance hoist of the present invention is not limited to such a usage form, and the seventh embodiment is not limited thereto.
As shown in the figure, it is also applicable to an overhead crane 70 having a moving rail 72 hung on two fixed rails 71.
In this case, the operation of transporting the case 20 between the conveyor 60 and the cart 50 is illustrated.

[0028]

According to the present invention, the winding drive means is composed of a servo motor having a negative actuation brake, and the servo motor is controlled by the feedback signal of the rotation speed detection sensor to instruct the drive of the servo motor. The section is provided with an input member held so that it can be reciprocally moved within a certain range by fingers, and a servo is performed by an output section that is loosely fitted between the movement paths of two action point portions formed on the input member. It is designed to output a motor drive signal,
Due to the gap between the point of action and the output section, the drive signal of the servo motor is output only when the movement operation of the input section moves more than a certain amount. Can be held without using the drive system, and by configuring the operation system of the drive system with play as described above, the drive system operation due to unexpected contact, shock, vibration, etc. Since it is possible to use a sensor that can be avoided and is sensitive to the output section, and a high-performance drive system can be used, desired movements can be performed easily and reliably, improving work efficiency and reducing the burden on workers. It can be performed.

Further, the gripping device has a swinging fulcrum near the lower end of each catching part in the gripping part main body having a catching part provided with an operating part and at least two parts projecting downward. A case in which a locking member is provided so as to be able to project inward of the grip portion main body around the center, and at least a part of the upper edge has a flange portion formed in a flange shape,
Since the engaging portion is configured to engage and hold below the engaging portion, the gripping device provided at the wire end of the hoist can store small articles or articles that are difficult to hold by hand in a case. When holding the case, the catching part that extends downward along the side surface of the case does not require a large space in the horizontal direction of the case. The work load can be reduced and workability can be improved.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment in which a balance hoist of the present invention is attached to a jib crane.

FIG. 2 is a perspective view of a gripping device.

FIG. 3 is a schematic diagram showing a basic structure of an operation unit.

FIG. 4 is a flowchart of control of the balance hoist of the present invention.

FIG. 5 is a schematic view showing a state where the gripping device holds a case.

FIG. 6 is a schematic view showing a state in which the holding device releases the holding of the case.

FIG. 7 is a schematic view showing a state in which the balance hoist of the present invention is attached to an overhead crane.

[Explanation of symbols]

 1 Jib Crane 2 Strut 3 Arm 4 Balance Hoist 5 Servo Motor 6 Take-up Drum 7 Wire 8 Control Line 9 Gripping Device 10 Operating Unit 11 Power Control Line 12 Control Panel 14 Servo Amplifier 15 Resolver 20 Case 20a Flange Part 30 Input Member 31 Power Point Part 32 Action point part 33 Support point 34 Elastic member 35 Output part 36 Strain gauge 39 Gap 40 Body frame 42 Capture part 43 Handle part 44 Locking part 44a Rotating spindle 45 Opening wire 46 Positioning part 47 Release switch 50 Basket wheel 60 Conveyor 70 Overhead crane 71 Fixed rail 72 Movable rail

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigeharu Yokoya 2-536 Iiyamaman-cho, Funabashi City, Chiba Prefecture 2-536 1-505 (72) Inventor Hiroki Shinohara 4-18-8 Benten, Urayasu City, Chiba Prefecture (56) References Special Kai 53-124852 (JP, A) JP-A-1-133900 (JP, A)

Claims (2)

[Claims] 1. A balance hoist having a gripping device for catching an object to be conveyed at a lower end portion of a wire connected to a winding drive means, and the gripping device provided with an operation section for adjusting drive of the drive means. The winding drive means is composed of a servo motor equipped with a negative-acting brake, and is controlled by the feedback signal of the rotation speed detection sensor, and the operation part is elastic so that it can be reciprocally moved within a certain range with fingers. Equipped with an input member that is
There is play between the movement paths of the points of action formed so as to face each other.
The output part, which is located in a fitting shape, comes into contact with the action point part,
It is designed to output the drive signal of the servo motor,
The operation of moving the input part due to the gap between the point of action and the output part
A balance hoist that is configured to output a drive signal for a servo motor only when is moved by a certain amount or more . 2. The gripping device used for the balance hoist according to claim 1, wherein the gripping part main body provided with the operation part includes a catching part in which at least two parts project downward, Each of the parts is provided with a rotation fulcrum near the lower end of the catching part, and a locking part that can project freely inwardly of the gripping part main body around the fulcrum is provided, and at least a part of the upper end edge is a flange. below the flange portion with respect to the case having a flange portion configured to Jo
So that the locking portion engages with the locking portion.
It is possible to rotate from the upper side of the
A gripping device configured to be locked at a position held by the flange portion .