JPH0338199B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a lifting device used for lifting workers or materials and lowering unnecessary parts for work at heights, and particularly relates to The middle boom is pivoted in an X-shape, and an upper boom and a lower boom that extend and retract in the axial direction are inserted into each middle boom, and the supply of hydraulic oil to a pair of telescoping mechanisms that lift the middle boom is adjusted to raise and lower it. After moving the table vertically and horizontally and memorizing the height and horizontal distance, the amount of movement is calculated based on the memorized distance information, and from this and the expansion and contraction data from the length measurement sensor, the expansion and contraction mechanism The present invention relates to an elevating device that automatically adjusts the supply of hydraulic oil to the elevating platform and allows the elevating platform to be raised and lowered diagonally.

[Conventional technology]

Assembly at high places such as highways and building construction,
For painting and repairs, a lifting device was used to raise and lower a lifting platform, and workers and materials were placed on this lifting platform to be lifted and lowered.

The outline of this conventional lifting device is explained with reference to Fig. 1. The middle booms A and B, which are hollow inside, are rotatably connected in an X-shape at the center by a shaft C. Upper booms D and E and lower booms F and G are inserted into the end faces so that they can appear and retract freely, and a lifting platform I is connected to the upper booms D and E, and a base is connected to the lower booms F and G. H
are connected. Between this base H and axis C, there is a pair of hydraulic cylinders J and K arranged in an isosceles triangle.
is interposed.

In this configuration, to raise the platform I, first raise the shaft C using hydraulic cylinders J and K, and then the upper booms D and E and the lower booms F and G are pulled out from the open ends of the middle booms A and B. , the lifting platform I moves upward away from the base H and rises. Here, in order for the lifting platform I to rise vertically with respect to the base H, upper booms D and E, lower booms F and G are required.
The amount of movement l drawn out from the open ends of the middle booms A and B must always be the same, and therefore a synchronization mechanism that regulates the amount of movement of each of the upper booms D and E and the lower booms F and G is required. It is provided.

[Problem that the invention seeks to solve]

By the way, the total length of the middle boom B, the upper boom E, and the lower boom G is a, the total length of the middle boom A, the upper boom D, and the lower boom F is b, and the base H Letting h be the height from to the lifting platform I, the relationship shown in FIG. 2 holds true. Lifting platform I raised to a height h in this way
As an elevating device for laterally moving a predetermined length L, the one described in Japanese Patent Application No. 124974/1983 has generally been proposed. According to such a lifting device, the length of one boom is constant (in this conventional example,
By shortening the length a) of the other boom (in this prior art example, from length b to length b ₁ ), the platform I can be moved by a distance L. However, such an elevating device has the disadvantage that when the elevating platform I is moved horizontally by a distance L, the height of the elevating platform I becomes _h1 . It was not possible to raise and lower it diagonally up to the horizontal distance L.

The present invention has been made in view of the above-mentioned problems, and after moving the lifting platform to a desired height and desired horizontal distance and storing the height and horizontal distance, the lifting platform is moved based on the stored distance information. An object of the present invention is to provide an elevating device that enables diagonal elevating between a base and a desired height and desired horizontal distance.

[Means to solve the problem]

The lifting device of the present invention that solves the above problems is based on the following principle. Now, the principle of the lifting device of the present invention will be explained using FIG. 3. In this figure as well, the same items as in FIG. 2 will be described with the same reference numerals. Here, M is the length of the lifting platform I, and is also the distance between the pivot points of the lower booms G and F.

First, when the elevator platform I is vertically raised by h and then stopped, the following equation holds true. That is, ^a2 = ^h2 + ^M2 , ^b2 = ^h2 + ^{M2∴h2 = a2} - ^M2 = ^b2 - ^M2 , where a=b...(1).

Next, when the elevator platform I is moved laterally by L, the following equation holds true.

That is, a _x ² = h ² + (M+L) ² b _x ² = h ² + (M-L) ² ...(2). Substituting equation (1) into equation (2), a _x ² = a ² −M ² +M ² +2ML+L ² = a ² +2ML+ ^{L 2} b _x ² = a ² −M ² +M 2 −2ML+L ² = a ² − 2ML＋L ²
...(3) becomes.

Therefore, based on the above equation (3), a _x and b _x are determined using the distance L as a variable, and horizontal movement is thereby performed. That is, take a predetermined height ΔL of L,
Substituting this into equation (3), △a _x = a ² +2M△L+△
L ² , △b _x = a ² −2M△L+△L ² and the obtained △
Using a _x and △b _x as a reference, compare this with the actual extension of the boom, and when this becomes zero, calculate △a _x and △b _x again using the above formula and compare this with the actual extension. Compare the elongation amounts, set the comparison result to zero, and repeat this one after another, Σ△L=L, Σ△a _x =a _x ,
By stopping when Σ△b _x = b _x ,
It is possible to horizontally move an arbitrary distance L while maintaining the height h. Here, the height h and the horizontal distance L will be memorized and used for the calculation of the next diagonal movement. Furthermore, using equation (2) above, as shown in FIG. 4, with h and L as variables, a _x , b _x
If the length of the boom is controlled by calculating the actual length of the boom every moment and comparing it with the actual length of the boom, it becomes possible to raise and lower the boom diagonally. In other words, by substituting a certain height of the height h as △h and a certain distance of the horizontal distance L as △L into equation (2), △a _x1 ² = △h ² + (M+△ L) ² △b _x1 ² = △h ² + (M-△L) ² ...(4) is obtained. Then, compare the actual boom lengths using these as standards, and when the comparison result is zero, substitute 2△h and 2△L into equation (2), and get △a _x2 ² = (2△h) ² + (M+2△L) ² △b _x2 ² = (2△h) ² + (M-2△L) ² ......(5) is calculated, and the actual boom length is calculated based on this. When the comparison result becomes zero, 3△
By substituting h and 3ΔL into equation (2) and comparing the actual boom lengths, it is possible to ascend diagonally. In other words, △a _x ² = (Σ△h) ² + (M+Σ△L) ² △b _x ² = (Σ△h) ² + (M−Σ△L) ² ...(6) Compare the actual boom extension with
If the extension of the boom is controlled to match Δa _x and Δb _x and stopped when ΣΔh=h and ΣΔL=L, diagonal ascent becomes possible. In addition, when lowering, it is sufficient to stop when h-ΣΔh=0 and L-ΣΔL=0.

Based on such knowledge, the lifting device of the present invention has the following features:
A movable vehicle body, a lifting platform located above the vehicle body that can be raised and lowered up and down, and a pair of middle booms that are rotatably supported in the center and combined in an X shape;
A lower boom that moves along the length of each middle boom and whose lower ends are connected to the vehicle body, and an upper boom that moves along the length of each middle boom and whose upper ends are connected to a lifting platform. A lifting device having a boom, a pair of telescoping mechanisms arranged in a V-shape between two spaced positions on the vehicle body and the middle boom to move the lifting platform vertically and horizontally; , a length measurement sensor attached to both of the X-shaped telescopic booms consisting of the upper, middle, and lower booms to measure the telescopic length of each telescopic boom and obtain a telescopic signal, and an operation input from the operation panel; The expansion/contraction data from the length measurement sensor is taken in and supplied to the above pair of expansion/contraction mechanisms in order to move the lifting platform vertically, horizontally, or diagonally up and down while keeping the lifting platform horizontal when the lifting platform is moved up and down by operation input. A control device that controls hydraulic fluid based on the above operation input and the above data is provided, and the control device is provided with a storage device that can store the height from the vehicle body and the horizontal movement distance from the reference position. Or, when selecting diagonal lifting operation, store the height or the height and horizontal movement distance in the storage device, and calculate data for horizontally moving the lifting platform while maintaining the memorized height when moving horizontally. Then, from this and the expansion/contraction data, calculate data for horizontally moving the platform, or moving it up and down diagonally between the target position and the reference position consisting of the stored height and horizontal movement distance, and from this and the above expansion/contraction data. The structure is such that the supply of hydraulic oil to the pair of telescopic mechanisms is controlled so as to move the elevator platform diagonally.

[Effect]

When the control device outputs a lift command, the hydraulic circuit operates and pressure hydraulic oil is supplied to both telescopic mechanisms. At this time, the control device compares the detection signals from the length measurement sensors, and the control device controls the hydraulic fluid supplied to the telescopic mechanism so that the control result becomes zero. As a result, the amounts of expansion and contraction of both expansion and contraction mechanisms are synchronized.

When the platform reaches the desired height, the control device stops the hydraulic oil supplied to the telescoping mechanisms, so the pressure hydraulic fluid is trapped in the circuit and both telescoping mechanisms remain extended. becomes. The height of the lifting platform at this time is stored in the storage device of the control device, and based on this height, the length of the boom corresponding to the horizontal movement distance is determined. The supply of hydraulic oil to the telescoping mechanism is controlled by the control device so that the detection signal from the length measurement sensor matches this determined value. As a result, the elevator platform moves horizontally by a desired horizontal distance while maintaining its height. In this way, the height and horizontal movement distance are given to the storage device, so based on these, the reference length of the boom is determined one after another using Equation (6), etc., and the actual boom length is determined from this. If controlled so that they match, it will be possible to ascend and descend in the diagonal direction. At this time, the lifting platform always
maintained horizontally.

〔Example〕

Hereinafter, the present invention will be explained based on illustrated embodiments.

FIG. 5 is a side view of an embodiment of the elevating device according to the present invention, showing the elevating mechanism in the lowest position.

FIG. 6 is a side view showing the elevating mechanism in a fully extended state. FIG. 7 is a rear view showing the state in FIG. 6.

The reference numeral 1 in the figure is a truck body.A front wheel 2 and a rear wheel 3 are pivotally supported on the front, rear, left, and right sides of the vehicle body 1, respectively.A driver's cab 4 is provided above the front wheels 2. Outriggers 5 are fixed to the center and left and right sides of the rear end, respectively. An elevating mechanism 6 is placed on the upper surface of the vehicle body 1. A elevating table 7 is fixed to the upper part of the elevating mechanism 6, and a handrail 8 is provided around the elevating table 7. The lifting mechanism 6
consists of four telescoping booms, each with 10 middle booms and 1 lower boom.
1. It is composed of an upper boom 12. The center of each of the two middle booms 10 is connected by a connecting shaft 13 so as to be rotatable in an X-shape, and the lower boom 11 and the upper boom 12 each have a connecting piece at their tip. 14 and 15 are fixed to each other, and the connecting piece 14 is connected to the fixed piece 16 fixed on the vehicle body 1.
and are rotatably connected by a pin, and the connecting piece 1
5 is rotatably connected to a fixed piece 17 fixed to the lower surface of the lifting table 7 by a pin.

The intervals between the fixed pieces 16 and the fixed pieces 17 are the same, and the vehicle body 1 and the lifting platform 7 are configured to be parallel even if the telescopic boom is extended in an X-shape. The two sets of the middle booms 10 are arranged parallel to each other with an interval between them, and the middle booms 10 inside each set are connected at the center by an operating shaft 18. The axes of the actuating shaft 18 and the connecting shaft 13 are arranged in a straight line. Both positions close to the fixed piece 16 of the vehicle body 1 and the operating axis 1
Hydraulic cylinders 19 and 20, which are telescopic mechanisms, are arranged between the two hydraulic cylinders 1 and 8, respectively.
9 and 20 are arranged to form an isosceles triangle with the operating axis 18 as the apex. In addition, middle boom 1
0 and 10 are provided with length measurement sensors 21 and 22 that measure the length of the boom. The length measurement sensors 21 and 22 have a built-in digital tachometer, and a belt-shaped body 23 is wound around the rotation shaft of the length-measuring sensors 21 and 22.
3 is provided, and one end of the band-like body 23 is engaged with the connecting piece 14 of the lower boom 11, so that the band-like body 23 moves forward and backward like a tape measure.

Next, FIGS. 8 and 9 show the internal structure of the above-mentioned telescopic boom, that is, the middle boom 10.
The middle stage boom 10 has a structure in which a thin steel plate is bent to have a hollow square cross section in the length direction, and a lower stage boom 11 is slidably inserted through one end of the middle stage boom 10. The lower boom 11 has a hollow rectangular cross section made by bending a thin steel plate, and the upper boom 12 inserted from the other open end of the middle boom 10 is slidably inserted into the lower boom 11. There is.

Fan-shaped shaft support pieces 24 and 25 are fixed to both ends of the middle boom 10, respectively, and a pair of guide rollers 26 and 27 are rotatably supported on the shaft support pieces 24 and 25, respectively. The guide rollers 26 are in contact with both side surfaces of the lower boom 11, and the guide rollers 27 are in contact with both side surfaces of the upper boom 12. A gearbox 28 is fixed to the end of the middle boom 10 close to the shaft support piece 25, and two sprocket wheels 29 and 30 are pivotally supported within the gearbox 28. The tip of the lower boom 11 (middle boom 10
The innermost position) and the tip of the upper boom 12 are connected by a chain 31, which is wound around the outer periphery of the sprocket wheels 29, 30 in an S-shape. This chain 31 connects the lower boom 11 and the upper boom 1.
2 are coordinated in their expansion and contraction amounts, and the middle boom 10, the lower boom 11, and the upper boom 12 move in and out by the same amount of expansion and contraction. The length measurement sensor 21 or 22 has a spiral spring 34 for winding the band 23 around the rotation shaft 33 of the digital tachometer 32 and for winding the band 23 around the rotation shaft 33.
It is set up and configured.

Further, FIG. 9 shows a cross section of the center of the middle boom 10, and a band-shaped holder 35 is wrapped around and fixed to the outer periphery of the center of the middle boom 10. A cylindrical connecting shaft 13 is fixed thereto, and an engaging piece 37 fixed with a screw 36 is fixed to the other holder 35.
By fitting the engaging piece 37 into an engaging groove 38 formed on the outer periphery of the connecting shaft 13, the two middle booms 10 are connected in an X-shape and their rotation is maintained freely. And one middle boom 1
On the side opposite to the connecting shaft 13 of the holding body 35 of 0, there is a support shaft 3.
9 is projected, and the operating shaft 18 is connected to this support shaft 39.

FIG. 10 is a system diagram showing a schematic configuration of a hydraulic control system according to an embodiment of the present invention. In this figure, parts unrelated to the control system, such as the driver's cab 4, are omitted.

In the figure, it is attached to the middle boom 10,
A length measurement sensor 21 that can measure the amount of boom extension;
The detection signal from 22 is taken into the control device 50. The control device 50 includes a processing unit 51 that takes in various information, performs arithmetic processing on the information, and outputs a control signal, and a storage unit 52 that stores predetermined data and the like.
and an external operation panel 53. A control signal from the control device 50 is given to a first hydraulic control section 55 and a second hydraulic control section 56 of the hydraulic circuit 54, respectively. First hydraulic control section 55 and second hydraulic control section 5
The pressure oil controlled by 6 is supplied to hydraulic cylinders 19 and 2.
It is designed to flow in and out between 0 and 0.

FIG. 11 is a system diagram showing the detailed configuration of the hydraulic control system. The output of the engine 57 is transmitted to a pump 58, the suction side of the pump 58 is connected to a tank 59 filled with pressure oil, and the discharge side of the pump 58 is connected to switching valves 60, 61. The switching valves 60 and 61 are electromagnetic valves that can switch between three positions at high speed, and are connected to two oil passages 62, 63, 64, and 65, respectively. 19 and 20 are connected to each other, and a check valve 6 is connected to the oil passages 63 and 65.
The operating sides of the cylinders 19 and 20 are connected through a parallel circuit of the control valves 6 and 68 and the control valves 67 and 69.

The processing section 51 of the control device 50 includes a microprocessor unit (MPU) 70 that performs various calculations,
A read-only memory (ROM) 71 that stores predetermined programs, etc., and a random access memory (RAM) 72 that stores processing programs, etc.
A digital input section (DI) 73 that takes in detection signals from the length measurement sensors 21 and 22; a digital input section (DIO) 74 that takes in signals from the operation panel 53 and lights up the display section of the operation panel 53;
A digital output unit (DO) 75 that outputs control signals for switching the switching valves 60 and 61, and a backup RAM that stores various data that must not be erased.
(Bu-RAM) 52, MPU70, ROM71,
RAM72, DI73, Bu-RAM52, DIO74
and a bus line 76 connecting the DO 75. Furthermore, the storage section 52 also serves as a backup RAM for the processing section 51.

The operation panel 53 includes a rising switch 80, a descending switch 81, a horizontal movement switch 82 for inputting forward and backward commands, and a height memory switch 8.
3. A switch 84 for selecting manual operation or automatic operation is provided, and these are operated by the processing unit 51.
It is connected to DIO74.

Next, the operation of this embodiment will be explained.

First, the engine 57 attached to the vehicle body 1 is operated, and the engine 57 drives the pump 57 to generate oil pressure. This oil pressure is the switching valve 60,6
However, when the switching valves 60 and 61 are in a stationary state, the hydraulic pressure is recovered to the oil tank 59 by a circuit (not shown).

Next, the operation of storing the height and horizontal movement distance will be explained using the flowchart of FIG.

FIG. 12 shows the result of manual operation.

The program is started at step 100. At step 101, when the lift switch 80 of the operation panel 53 is turned on, the process moves to step 102. Step 102
Then, when the DIO 74 takes in this and gives it to the MPU 70, the MPU 70 outputs an upward control signal to the switching valves 60 and 61 via the DO 75. As a result, hydraulic pressure is applied to the hydraulic cylinders 19 and 20 via the oil passages 62 and 64, and both hydraulic cylinders 1
9, 20 are supplied with pressure oil. In step 103, the signals from the length measurement sensors 21 and 22 are sent to the DI 73.
The data is taken into the Bu-RAM 52 via.

In step 104, the signals from the length measurement sensors 21 and 22 taken in are compared, and if there is a deviation in the comparison results, a control signal corresponding to the deviation is output to one of the switching valves 60 or 61. In step 105, the switching valves 60 and 61 are switched and controlled.
A predetermined amount of oil is supplied to the hydraulic cylinder 19 or 20 so that the deviation is eliminated. As a result, pressure oil is supplied to both hydraulic cylinders 19 and 20, and the hydraulic cylinder 19 is extended, and at the same time, the hydraulic cylinder 20 is extended in synchronization with the hydraulic cylinder 19. The pressure oil discharged by the hydraulic cylinders 19 and 20 passes through the control valves 67 and 69 to the oil tank 59.
will be collected. When the hydraulic cylinders 19 and 20 are operated and their cylinder rods are projected, the middle boom 10 is lifted upward, and the lower boom 11 and the upper boom 12 are accordingly pulled out by the middle boom 10. , the lower boom 11 and the upper boom 12 are connected by a chain 31, so the lower boom 11 is connected to the middle boom 1.
0, the chain 31 fixed to the tip of the lower boom 11 connects to the sprocket wheels 29, 3.
The lower end of the upper boom 12 is pulled by the movement of the chain 31, and the upper boom 12 is pulled out from the upper end opening of the middle boom 10. Furthermore, since the chain 31 does not extend, the amount of extension of the lower boom 11 and the upper boom 12 is the same, and the amount of extension of each lower boom 11 and upper boom 12 in a pair is the same, and the middle boom 10 is The lifting platform 7 is lifted by rotating around the connecting shaft 13 in an X-shape.
Middle boom 1 by these hydraulic cylinders 19 and 20
0, the hydraulic cylinders 19 and 20 are both arranged to form an isosceles triangle with the connecting shaft 13 as the center, so if the amount of extension of each cylinder rod is the same, the connecting shaft 13 will always be aligned with the vehicle body 1. It will rise in the vertical direction. Both hydraulic cylinders 19 and 20 are synchronized so that the amount of extension thereof is the same, and the extension of the cylinder rod is the same amount at any time. To explain the relationship between this movement amount using FIG. 13, both hydraulic cylinders 19,
The extension amount W of each boom 20 is the same, and the connecting shaft 13 is raised in a straight line, and the extrusion amount Z of the lower boom 11 and upper boom 12 is the same, and all the booms 11 and 12 are moved by the same amount. will be synchronized.

In step 106, both hydraulic cylinders 1
9 and 20, it is determined whether or not the lifting platform 7 has reached a predetermined height h. If it has not reached the predetermined height h, the process returns to step 101, and if it has reached the height, the lift switch 80 is stopped (step 107). As a result, the switching valves 60, 61 return to their neutral positions, and the hydraulic circuits of the respective hydraulic cylinders 19, 20 are closed while they are in the extended state, and the lifting platform 7 is not lowered because it is held in that position (step 108). After stopping at a predetermined height, in step 109, the length measurement sensor 21,
The height h can be calculated using the 22 detection signals and the above equation (1).
The MPU 70 calculates this and stores it in the Bu-RAM 52. At this time, if you wish to perform automatic operation next time, you can ensure the reliability of the operation by pressing the memory switch 83.

In step 110, next, press "forward movement" of the horizontal movement switch 82, and the process moves to step 111.
Based on equation (3), a _x and b _x are calculated every moment by the MPU 70, and the values are stored in the Bu-RAM 52.

In step 112, a control signal is given to the switching valves 60, 61 via the DO 75 so that the detection signals from the length measurement sensors 21, 22 match the above-determined _ax , _bx , and here, ax, _{bx are} determined. A comparison is made between b _x and the detection signal, and if they do not match, step 112 is repeated until they match. In step 113, it is determined whether the platform 7 has moved to a predetermined horizontal distance L. If it has not moved, the process returns to step 110, and if it has moved, the process proceeds to step 114. At step 114, the switch 82 is stopped, and at step 115
Then, the horizontal movement of the lifting platform 7 is stopped, and this distance L is stored in the Bu-RAM 52 by pressing the storage switch 83 or without operating it.

In step 116, when the "backward movement" of the horizontal movement switch 82 is pressed, the value stored in the Bu-RAM 52 is read out in reverse, and the detection signals from the length measurement sensors 21 and 22 are made to match based on that value. The switching valves 60 and 61 are controlled accordingly. Step 117
Then, it is determined whether the lifting platform 7 has moved by the distance L, that is, to the original position, and if it has moved, the process proceeds to step 118.
and stop, and when not moving, step
Move to 116. Next, when the lowering switch 81 is pressed in step 118, a control signal is outputted from the DO 75 to the switching valves 60 and 61 in step 119. As a result, the switching valves 60 and 61 are switched in the opposite direction,
Pressure oil from the pump 58 is injected into the hydraulic cylinders 19, 20 through oil passages 63, 65 and check valves 66, 68, and the hydraulic cylinders 19, 20 are contracted. The hydraulic oil discharged by the hydraulic cylinders 19 and 20 returns to the oil tank 59 through oil passages 62 and 64. Even when the two hydraulic cylinders 19 and 20 are contracted, the MPU 70 synchronizes them, so the contraction amounts of the two hydraulic cylinders 19 and 20 are synchronous, and the connecting shaft 13 of the middle boom 10 is perpendicular to the vehicle body 3. descend to If the bottom has not been reached at step 120, the process returns to step 118; if the bottom has been reached, the process continues.
Move to 121. In step 121, everything is brought to a halt state, and this routine ends.

Next, the diagonal vertical movement will be explained using the flowchart shown in FIG.

FIG. 14 shows automatic operation, and the same figure shows oblique upward movement and the same figure shows oblique downward movement.

In the figure, at step 200, a program is started. When the switch 84 is pressed to set it to automatic, and the switch 80 is pressed, automatic tilting is performed (step 201). In step 202, ΔH and ΔL are determined from H and L. In step 203, △a _x and △b _x are determined from equation (6). In the next step 204, detection signals from the length measurement sensors 21 and 22 are taken in. In step 205, the Δa _x and Δb _x obtained above are compared with the detection symbol, and a control signal corresponding to the deviation is output to the hydraulic circuit 54. In step 206, the switching valves 60 and 61 of the hydraulic circuit 54 are switched in accordance with the control signal to determine whether the deviation has become zero. If the deviation is not zero, the process moves to step 204, and the processes from step 204 onwards are performed again. Ru. When it becomes zero, it is determined whether Σ△h=h and Σ△L=L, and the process moves to step 203 until Σ△h=h and Σ△L=L, and Σ△h=h , Σ△L=
When the voltage reaches L, the hydraulic circuit 54 is stopped (step 208). Then, this routine ends (step 209).

In the figure, the program is activated at step 300. When the switches 84 and 81 are pressed, automatic diagonal lowering occurs (step 301). step 302
Then △a _x ² = (h-Σ△h) ² + (M+L-Σ△L) ² △b _x ² = (h-Σ△h) ² + {M-(L-Σ△L)} ²
… Find (7). In step 303, the length measurement sensor 21,
The detected symbols from 22 are taken in. In step 304, the detection symbols are compared using Δa _x and Δb _x as references, and a control signal corresponding to the deviation is output to the hydraulic circuit 54. In step 305, the switching valves 60 and 61 of the hydraulic circuit 54 are controlled in accordance with the deviation signal, and it is determined whether the deviation has become zero. If the deviation is not zero, the process returns to step 303, but if the deviation is zero, the process returns to step 303. Move to 306. In step 306, h−Σ△h
= 0, determine whether L-Σ△L = 0,
If it is not zero, return to step 302 and perform the steps from step 302 onwards, but if it is zero, lift platform 7
has reached the lowest position, so stop the control (step
307, 308).

In this way, according to this embodiment, when the automatic operation switch 84 is operated, if the height h and the horizontal distance L are set, △
a _x and △ _b will go up and down diagonally.

In the above embodiment, since the switching valves 60 and 61 are capable of opening and closing in a pulsed manner, it is easy to finely adjust the amount of movement. In addition, length measurement sensors 21, 2
2 may be of an analog type, in which case the detection signal may be inputted via an analog-to-digital converter instead of the DI 73.

〔Effect of the invention〕

Since the present invention is configured as described above, once the lifting platform has been moved to a desired height and a desired horizontal distance, and the height and horizontal distance have been memorized, the elevating platform can be moved in the diagonal movement direction based on this stored information. Desirable movement data for the telescoping mechanism is calculated, and by comparing this data with actual telescoping data, the supply of hydraulic oil to the telescoping mechanism is controlled so that the lifting platform can be raised and lowered in an oblique direction.

In addition, the present invention allows diagonal elevation, so
This will shorten the time it takes to load and unload luggage.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an outline of a conventional lifting device;
Fig. 2 is a schematic diagram shown to explain the operation of a conventional lifting device, Figs. 3 and 4 are schematic diagrams shown to explain the principle of the present invention, and Fig. 5 is a schematic diagram shown to explain the principle of the present invention. FIG. 6 is a side view showing an example of the elevating mechanism in the state shown in FIG. Fig. 8 is a side sectional view showing the inside of the middle boom, Fig. 9 is a longitudinal sectional view of the middle boom near the operating axis, and Fig. 10 is a system diagram showing the control system of an embodiment of the lifting device of the present invention. , 11th
The figures are a system diagram showing Fig. 10 in detail, Fig. 12 is a flowchart shown to explain the operation of the control system, Fig. 13 is a schematic diagram showing the relationship between the lifting mechanism and the hydraulic expansion and contraction mechanism, and Fig. 14. and are flowcharts shown to explain the vertical lifting operation. 1... Vehicle body, 6... Lifting device, 7... Lifting platform,
10...middle boom, 11...lower boom, 12
...Upper boom, 19,20...Hydraulic cylinder,
21, 22...Length measurement sensor, 50...Control device, 54...Hydraulic circuit.

Claims (1)

[Scope of Claims] 1. A movable vehicle body, a lifting platform located above the vehicle body that can be raised and lowered up and down, a pair of middle stage booms rotatably supported at the center and combined in an X shape, and each middle stage. A lower boom that moves along the length of the boom and whose lower end is connected to the vehicle body, and an upper boom that moves along the length of each middle boom and whose upper end is connected to the lifting platform. a pair of telescoping mechanisms disposed in a V-shape between two spaced apart positions on the vehicle body and the middle boom and capable of moving the platform in the vertical and horizontal directions; A length measurement sensor is attached to both sides of the X-shape of the telescopic boom consisting of the upper, middle, and lower booms, and measures the telescopic length of each telescopic boom and obtains a telescopic signal, as well as operation input from the operation panel and length measurement. Hydraulic oil is supplied to the above-mentioned pair of telescopic mechanisms in order to capture the telescopic data from the sensor and move the vertical, horizontal, or diagonal vertical, horizontal, or diagonal movement of the elevating platform while keeping the elevating platform horizontal when the elevating platform is moved up and down by operation input. and a control device that controls the vehicle based on the above-mentioned operation input and the above-mentioned data, and the control device is provided with a storage device that can store the height from the vehicle body and the horizontal movement distance from the reference position, and When selecting the lifting/lowering operation, the height or the height and the horizontal movement distance are stored in the storage device, and data for horizontally moving the lifting platform while maintaining the memorized height during horizontal movement is calculated thereafter. Calculate the data for moving the platform horizontally from the above data and the expansion/contraction data, or move the platform diagonally up and down between the target position and the reference position based on the stored height and horizontal movement distance. An elevating device characterized in that it is configured to control the supply of hydraulic oil to the pair of telescoping mechanisms so as to move the elongated mechanism diagonally.