JPH10338499A - Device and method for raising and lowering heavy article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate work for positioning a heavy article in the specified height position by vertically moving the heavy article by using a cross link mechanism. SOLUTION: When an operator A operates an operation lever 11 so as to raise and lower a heavy article 1 on a table 3, a force sensor 13 detects operating force and the operating direction, and the detected signal is input into a computing circuit 49 through an A/D and D/A converting unit 15. The computing circuit 49 outputs a control signal so that air from an air source 41, having the amount corresponding to operating force may be supplied to one pressure chamber 39 of an air cylinder 31 through a first proportional valve 43 when the operating direction is a direction for raising the heavy articile 1, while, it outputs a control signal so that air from the air source 41, having the amount corresponding to operating force may be supplied to the other pressure chamber 45 of the air cylinder 31 through a second proportional valve 47 when the direction is a direction for lowering the heavy article 1. Therefore, the air cylinder 31 is operated, a cross link mechanism 19 is extended and contracted, and the heavy article 1 is raised and lowered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for lifting and lowering a heavy object using a cross-link mechanism, and a method of lifting the same.

[0002]

SUMMARY OF THE INVENTION An object of the present invention is to facilitate the operation of moving a heavy object up and down by using a cross link mechanism to position the object at a predetermined height.

[0003]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention firstly provides a cross link mechanism for supporting a table on which a heavy object is placed at an upper end, and an expansion and contraction operation of the cross link mechanism. An operating unit provided on the table and operated by the operator to move the heavy object up and down, and an operation for detecting the operating force and the operating direction of the operator on the operating unit It is configured to include a detection unit and a control unit that causes the drive mechanism to perform an operation corresponding to the operation force and operation direction detected by the operation detection unit.

According to the heavy lifting apparatus having such a configuration, when the operator operates the operation unit, the operation detection unit detects the operation force and operation direction, and the control unit is driven based on the detection information. The mechanism is operated to cause the cross link mechanism to expand and contract, whereby the heavy object moves in the direction corresponding to the operation direction according to the operator's operation force.

Secondly, the driving mechanism is constituted by a cylinder mechanism, and a first control which can be switched between a position for supplying the working fluid and a position for discharging the working fluid to one of the pressure chambers in the cylinder mechanism and which can adjust the flow rate. A valve and a second control valve switchable between a position for supplying the working fluid and a position for discharging the working fluid and capable of adjusting the flow rate with respect to the other pressure chamber,
The control unit controls the operations of the first and second control valves in accordance with the operation force and the operation direction detected by the operation detection unit.

According to the above configuration, when the operator performs an upward operation on the operation unit to raise a heavy object, for example, the first control valve causes one of the working fluids in an amount corresponding to the operation force to be supplied to one of the operation units. The second control valve is operative to supply working fluid to the pressure chamber and discharge the working fluid from the other pressure chamber. Conversely, when the operator performs an downward operation on the operation unit to lower the heavy object, the second control valve is operated to supply an amount of working fluid corresponding to the operation force to one of the pressure chambers. At the same time, the first control valve operates to discharge the working fluid from the other pressure chamber.

Third, each of the first and second control valves is constituted by a proportional valve, and a vertical position detecting unit for detecting a vertical position of a heavy object is provided. The control unit controls the proportional valve with respect to the proportional valve. The coefficient is changed according to the vertical position of the heavy object detected by the vertical position detection unit.

According to the above construction, when the heavy object is at the low position, a large thrust is obtained for the cross link mechanism, and when the heavy object is at the high position,
To reduce the thrust on the crosslink mechanism,
By changing the control proportional coefficient for the proportional valve of the control unit, the lifting operation of the heavy object can be stably performed.

Fourthly, when an operator operates an operation section to perform a lifting operation on a heavy object that moves up and down by the cross link mechanism, the cross link mechanism is operated in accordance with the operation force and operation direction. The drive mechanism is operated to perform the expansion and contraction operation.

[0010] According to the above-described lifting method, a heavy object can be stably moved up and down because the drive mechanism operates in accordance with the operation force and operation direction of the operator, and the cross link mechanism expands and contracts.

[0011]

According to the first aspect of the present invention, the control unit operates the drive mechanism in accordance with the operation force and the operation direction of the operator on the operation unit to cause the cross link mechanism to expand and contract, thereby making the heavy object heavy. Is lifted and lowered, so that the lifting and lowering operation of the heavy object can be performed stably, and the positioning at the predetermined position can be easily performed.

According to the second invention, the working fluid is supplied to or discharged from the cylinder mechanism by the operation of the first and second control valves according to the operating force and the operating direction of the operator on the operating section. Since the cross link mechanism expands and contracts, the lifting and lowering operation of the heavy object can be stably performed, and the positioning at the predetermined position can be easily performed.

According to the third aspect of the present invention, when the heavy object is at the low position, a large thrust is obtained for the cross link mechanism, and when the heavy object is at the high position, the thrust for the cross link mechanism is obtained. Since the control proportional coefficient of the control unit with respect to the proportional valve is changed so as to reduce the weight, the operation of lifting the heavy object can be stably performed, and the positioning at the predetermined position can be easily performed.

According to the fourth aspect, the driving mechanism operates in accordance with the operation force and the operation direction of the operator, the cross link mechanism expands and contracts, and the heavy object can perform a stable lifting operation. Positioning at a predetermined position can be easily performed.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an overall structural view of an apparatus for lifting a heavy object according to an embodiment of the present invention. A heavy object 1 is placed on a table 3. The table 3 includes an upper plate 5, a lower plate 7, and a connecting block 9 for connecting these two plates 5, 7 to each other.
It is composed of An operation bar 11 as an operation unit is disposed between the upper plate 5 and the lower plate 7.
Is connected to the lower plate 7 via a force sensor 13 including, for example, a load cell and a strain gauge as an operation detection unit, and is operated by the worker A. The operation bar 11
Is installed in a free state with respect to the connection block 9.

The force sensor 13 detects the heavy object 1 by the worker A.
This detection signal detects an A / D conversion function of converting an analog signal into a digital signal and a D / A conversion function of converting a digital signal into an analog signal. A /
The data is input to the D / D / A conversion unit 15.

The table 3 is moved up and down by a cross link mechanism 19 installed on a base 17. In the cross link mechanism 19, a first link member 21 and a second link member 23, each of which is disposed in a pair in a direction orthogonal to the plane of the drawing in the figure, are connected by a connecting portion 25 so as to intersect. The first link member 21 has an upper end located on the right side in the figure rotatably connected to and fixed to the lower plate 7, and a lower end located on the left side is left and right in the figure with respect to the base 17 via the roller 27. It can move in any direction. On the other hand, the second link member 23
The lower end located on the right side in the figure is rotatably connected and fixed to the base 17, and the upper end located on the left side is movable in the left-right direction with respect to the lower plate 7 via the roller 29. .

A cylinder mechanism serving as a drive mechanism for causing the cross link mechanism 19 to expand and contract in the vertical direction is constituted by an air cylinder 31, which has a cylinder body 33 fixed to the base 17 and a first cylinder. The tip of a cylinder rod 35 is rotatably connected to the link member 21. A rotary type displacement sensor 37 is provided on the first link member 21 at a portion to which the tip of the cylinder rod 35 is connected, as a vertical position detecting unit.

The rotary type displacement sensor 37 moves the cylinder rod 35 forward and backward, in other words, the cross link mechanism 1.
The vertical movement of the cylinder 9 changes the angle of the cylinder rod 35 with respect to the first link member 21, and detects the change in the angle as the vertical position of the heavy object 1. The detection signal of the rotary displacement sensor 37 is A / D, D /
It is input to the A conversion unit 15.

One pressure chamber 39 of the air cylinder 31;
Between the air source 41 as a pressure source, a first proportional valve 43 as a first control valve is provided. The first control valve 43 is capable of switching between a position for supplying air, which is a working fluid from the air source 41, to the one pressure chamber 39 and a position for discharging air, and is also capable of adjusting a flow rate. The other pressure chamber 45 of the air cylinder 31 and the air source 4
1, a second proportional valve 47 as a second control valve is provided. The second control valve 47 can switch between a position for supplying air from the air source 41 to the other pressure chamber 45 and a position for discharging the air from the other pressure chamber 45, and can also adjust the flow rate.

Each of the first and second proportional valves 43 and 47 has an A /
It is activated by an output signal from the D / D / A conversion unit 15. The A / D and D / A conversion unit 15 is connected to an arithmetic circuit 49 as a control unit.
Receives the input of the digital signal of the force sensor detection value converted by the A / D and D / A conversion unit 15, and determines the operation force and the operation direction. The arithmetic circuit 49 operates in the heavy object 1 direction.
If it is determined that the direction is to move the pressure upward, the first proportional valve 43 is operated to supply the air from the air source 41 to one pressure chamber 39 of the air cylinder 31 according to the operation force. Output a signal. On the other hand, if it is determined that the direction is for moving the heavy object 1 downward, the second proportional valve 47 is operated to supply air from the air source 41 to the other pressure chamber 45 of the air cylinder 31 in accordance with the operating force. And outputs a signal for operating the same.

The arithmetic circuit 49 receives the digital signal of the detected value of the rotary displacement sensor converted by the A / D / D / A conversion unit 15, that is, the first position data of the heavy object 1, and receives the first data. The control proportional coefficient for the proportional valve 43 is changed. Specifically, for example, when lifting the heavy object 1, when the heavy object 1 is at a low position, a large thrust is obtained for the cross link mechanism 19, and the heavy object 1 is at a high position. At times, the control proportional coefficient is changed according to the vertical position so that the thrust on the cross link mechanism 19 can be small.

FIG. 2 shows the upward component force f of the cylinder output F when the inclination angle of the air cylinder 31 with respect to the base 17 is θ and the cylinder output of the air cylinder 31 is F. According to f / F = sinθ, F = (1 / sinθ) · f.

Here, it is assumed that the operating force of the worker A is fs, the gain representing the operational feeling is K (corresponding to a proportional coefficient based on the position information detected by the rotary displacement sensor 37), and f = K · fs. , Cylinder output F is as follows: F = (K / sin θ) · fs

FIG. 3 is a control block diagram for operating the air cylinder 31. When the weight 1 is in the equilibrium state, the reference pressure is applied to the two pressure chambers 39 and 45 of the air cylinder 31, and the weight 1 is in a balanced state. From this state, when the heavy object 1 is raised rightward in the drawing, that is, in FIG. 1, the output value from the force sensor 13,
That is, the first proportional valve 43 operates so that the air supplied to the one pressure chamber 39 of the air cylinder 31 becomes “the reference pressure + the pressure proportional to the operating force” based on the operating force and the operating direction information. Conversely, when lowering the heavy object 1 to the left in the figure, that is, in FIG. 1, the second proportional valve 47 is activated by the operating force and the operating direction information, which are output values from the force sensor 13. It operates so that the air supplied to the other pressure chamber 45 of “31” becomes “reference pressure + pressure proportional to the operating force”.
Further, the control proportional coefficient for the first and second proportional valves 43 and 47, that is, the gain K is determined by the rotary displacement sensor 3
7, that is, variable according to the vertical position information of the heavy object 1.

Next, the operation of the above-described heavy lifting apparatus will be described. When the operator A operates the operation bar 11 upward or downward in order to raise and lower the heavy object 1, the force sensor 13 detects the operation force and operation direction at that time, and the rotary displacement sensor 37 detects the weight. Thing 1
The vertical position of is detected. Each analog signal detected by the force sensor 13 and the rotary displacement sensor 37 is A /
The signals are received by the D / D / A conversion unit 15, converted into digital signals, and taken into the arithmetic circuit 49.

The arithmetic circuit 49 is provided with the force sensor 13
The operation force and the operation direction are discriminated from the detected value of the first proportional valve 43. If the operation direction is, for example, the direction of moving the heavy object 1 upward, the first proportional valve 43 is set to the air from the air source 41 as the operation force. The air cylinder 31 is operated via the A / D and D / A conversion unit 15 to supply the pressure to the one pressure chamber 39 of the air cylinder 31 accordingly. At this time, the second proportional valve 47 is switched so that air is discharged from the other pressure chamber 45. Thus, the air cylinder 31 extends the cylinder rod 35 and the cross link mechanism 19, and the heavy object 1 rises to a height corresponding to the operating force, in other words, the height intended by the worker A, Positioning at a predetermined position is easily performed.

At this time, the arithmetic circuit 49 changes the proportional coefficient for the first proportional valve 43 in accordance with the detected value of the rotary displacement sensor 37, that is, the vertical position of the heavy object 1. Specifically, when the heavy object 1 is at a low position, a large thrust is obtained for the cross link mechanism 19, and when the heavy object 1 is at a high position, a small thrust is applied to the cross link mechanism 19. The proportional coefficient is changed so that thrust is sufficient. Thereby, the lifting operation of the heavy object 1 becomes stable at any position from the low position to the high position.

When the operation direction of the operation bar 11 by the worker A is the direction of moving the heavy object 1 downward,
The arithmetic circuit 49 supplies the second proportional valve 47 to the A / D and D / A conversion unit 1 so as to supply the air from the air source 41 to the other pressure chamber 45 of the air cylinder 31 according to the operation force.
Operate via 5. At this time, the first proportional valve 43
Switching is performed so that air is discharged from one pressure chamber 39. However, when the heavy object 1 is moved downward, the own weight of the heavy object 1 acts on the air cylinder 31, so that the control is performed in consideration of the own weight.

As described above, when the worker A raises and lowers the heavy object 1, by operating the operation bar 11, the air cylinder is operated in accordance with the operating force and operation direction at that time and the vertical position of the heavy object 1. 31 operates and the cross-link mechanism 19 expands and contracts, so that the worker A can handle the heavy object 1 as a lightweight object, can perform the lifting / lowering operation stably, and easily perform positioning to a predetermined position. Becomes possible.

FIG. 4 shows another embodiment of the present invention. This embodiment is different from the rotary type displacement sensor 37 shown in FIG.
7, a position detector 51 is provided. When the position detector 51 detects the position of the roller 27 in the left-right direction in the drawing in accordance with the expansion / contraction operation of the cross link mechanism 19, the vertical position of the heavy object 1 is detected.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a heavy object lifting / lowering device showing an embodiment of the present invention.

FIG. 2 is a model diagram showing an upward component force f of the cylinder output F when the inclination angle of the air cylinder is F and the cylinder output is F in the heavy lifting device of FIG.

3 is a control block diagram for operating an air cylinder in the heavy lifting device of FIG. 1;

FIG. 4 is a front view of a cross link mechanism according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heavy object 3 Table 11 Operation bar (operation part) 13 Force sensor (operation detection part) 19 Cross link mechanism 31 Air cylinder (cylinder mechanism, drive mechanism) 37 Rotary displacement sensor (vertical position detection part) 39 One pressure chamber 43 first proportional valve (first control valve) 45 other pressure chamber 47 second proportional valve (second control valve) 49 arithmetic circuit (control unit)

Claims (4)

[Claims] 1. A cross-link mechanism for supporting a table on which a heavy object is placed at an upper end, a drive mechanism for performing an expansion / contraction operation of the cross-link mechanism, and an operator provided on the table so that an operator can handle the heavy object. An operation unit operated to move up and down in the vertical direction, an operation detection unit that detects an operation force of the operator on the operation unit and the operation direction, and an operation corresponding to the operation force and the operation direction detected by the operation detection unit And a control unit for causing the drive mechanism to perform the following. 2. A drive mechanism comprising a cylinder mechanism, a first control valve switchable between a position for supplying a working fluid and a position for discharging a working fluid to one of the pressure chambers in the cylinder mechanism and capable of adjusting a flow rate; A second control valve switchable between a position for supplying the working fluid and a position for discharging the working fluid and capable of adjusting the flow rate with respect to the other pressure chamber, wherein the control unit detects the operating force detected by the operation detection unit. 2. The apparatus according to claim 1, wherein the operation of each of the first and second control valves is controlled in accordance with an operation direction. 3. The control valve according to claim 1, wherein each of the first and second control valves comprises a proportional valve, and a vertical position detecting unit for detecting a vertical position of the heavy object is provided. 3. The apparatus according to claim 2, wherein the height of the heavy object is changed according to the vertical position of the heavy object detected by the vertical position detecting unit. 4. An expansion / contraction operation of the cross link mechanism in accordance with an operation force and an operation direction when an operator operates an operation unit to perform a lifting operation on a heavy object that moves up and down by the cross link mechanism. A lifting / lowering method of a heavy object, wherein a driving mechanism is operated to perform the operation.