JPH0825719B2 - Aerial work vehicle - Google Patents

Description

Detailed Description of the Invention

[0001]

INDUSTRIAL APPLICABILITY The present invention is used for work in high places such as construction, assembly and painting of highways and high-rise buildings. TECHNICAL FIELD The present invention relates to an aerial work vehicle used for unloading materials from a high position, and particularly to an aerial work vehicle in which an elevating mechanism for elevating an elevating table is formed with a simple structure similar to a hydraulic cylinder.

[0002]

2. Description of the Related Art In the construction of highways, high-rise buildings, etc., aerial work vehicles have been widely used for the construction, assembling, and painting work of which an elevating platform is moved up and down. It was also widely used for repairing traffic lights and lighting at high altitudes. In this aerial work vehicle, it is possible to load a worker, materials and the like on an elevator and lift them, and to load and unload unnecessary materials from a work site at a high altitude.

In this conventional aerial work vehicle, a so-called (scissors type) expansion / contraction mechanism in the form of a pantograph, in which a pair of arms and the center thereof are pivotally attached to form one set, and a plurality of sets of arms are vertically connected, has been used. It was widely used.
In order to increase the maximum lifting capacity of the lifting platform in this mechanism, it is necessary to increase the length of the arms of each group or increase the number of arms to be connected. Therefore, in order to design an elevating mechanism capable of increasing the ascending height, it was necessary to use a large number of sets of pantographs. In such a mechanism, the height of the elevating mechanism in a folded state of the pantograph becomes high, and it becomes troublesome for a worker to get on and off the platform or to load and unload materials.

[0004] In order to eliminate these disadvantages, and various proposals have hitherto been made, for example, US patent 38206
A structure such as the one described in No. 31 is also proposed. In this proposed structure, the lower boom and the upper boom, which can move linearly with respect to the middle boom, are inserted into and removed from the middle boom, and the lower boom is pivotally supported by a pin on the vehicle body side at the lower end. The upper boom is assembled so that the upper end of the upper boom is pivotally supported on the platform with a pin to form an X shape. With this structure, the length of the boom itself becomes longer,
In the folded state, the height of the platform can be lowered and the platform can be lifted to a high position.

However, according to the present invention, since the mechanism for extending the lower boom and the upper boom from the middle boom is composed of the screw and the female screw meshing with the screw, the moving speed of the lower boom and the upper boom relative to the middle boom is slow and the moving speed is high. It was not possible to respond to the platform. Moreover, since the lower boom and the upper boom are slid by the screw provided in the center of each middle boom, the total length of the lower boom and the upper boom can only be set to about half the length of the middle boom. It is a thing. Therefore, the lengths of the lower boom and the upper boom that extend and retract from the middle boom can only be set to about half the length of the middle boom, and the platform cannot be lifted higher.

Also, by inserting another boom into the boom,
A structure has also been proposed in which the entire length of the telescopic boom itself is lengthened. For example, Japanese Patent Laid-Open Publication No. 1195, 1978
In Fig. 4 of the drawing of No. 56, a thin multi-stage boom and an upper boom are inserted into a thick middle boom, and the boom inserted inside is pulled out from the middle boom to increase the total length of the boom. Therefore, a structure for lifting the platform high has been proposed.

However, in the present invention, there is no mechanism for synchronizing the amount of expansion and contraction between the lower boom and the upper boom that are pulled out from the middle boom, and they move individually, and the movement amount depends on the link mechanism by the bar. It is a regulation. For this reason, the platform cannot be lifted in the vertical direction while being held horizontally, and cannot be lifted to the intended vertical upper position. Also, when the lower and upper booms housed in the middle boom expand and contract, their movements are regulated by the link mechanism formed by the bar, so perfect synchronization of the movements of the two is impossible. there were. For this reason, the lower boom cannot be connected to the vehicle body and the upper boom cannot be connected to the platform by a pin or the like, and an error that cannot be synchronized has to be made by the rollers in contact with the vehicle body and the platform. Due to this structure, the platform is subject to rolling by the link mechanism as it is, and has a structure that easily shakes, easily swings due to wind or the like and is extremely unstable, which gives anxiety to workers.

In FIG. 4 of the drawing, the X-shaped middle boom is rotated by an externally attached hydraulic cylinder, and the lower boom and the upper boom are pulled out by the rotation of the middle boom. The configuration is shown. The amount of pulling out of the upper boom and the lower boom is regulated by the link mechanism. For this reason, the operating force of the hydraulic cylinder acts linearly on the upper boom and the lower boom, and when the hydraulic cylinder is pulled out to the maximum, the lengths of the upper boom and the lower boom are not pulled out as much as the entire length of the middle boom. Therefore, the maximum extension length of the entire boom to be extended cannot be extremely lengthened.

Next, as a structure for extending the entire length of the folded boom in the longitudinal direction, for example, Japanese Patent Application No.
A configuration such as No. 18492 of 2 years is also proposed.

In this structure, the outrigger box is horizontally fixed to a part of the vehicle body, the inside of the outrigger box is divided by partition walls, and the outrigger beams are slidably inserted into the respective storage chambers. An operating cylinder is stored in one of the storage chambers. And both outrigger beams are connected by a rope. In this configuration, by activating the actuation cylinder, the outrigger beam can be retracted from inside the outrigger box, both outrigger beams can move in opposite directions, and each outrigger beam pulled out from inside the outrigger box is about the length of the outrigger box. It can be extended to. This configuration is effective in extending the outrigger beam from the outrigger box for a long time.

However, this structure shows a structure for an outrigger for lifting the vehicle body and fixing it to the ground. Even if it is diverted to an aerial work vehicle as it is, the lifting platform can be moved up and down. It was something that could not be done. Further, in the drawings described in this publication, both ends of both outrigger beams are not connected to any structures, and a configuration is shown in which the outrigger beams are simply expanded and contracted in the left and right horizontal directions. It's just that.

From such a point of view, a number of lifting mechanisms have been devised which are constructed such that a plurality of booms can be telescopically inserted into the inside of the arm and one arm can be extended in the length direction thereof. For example, Japanese Patent Application No. 134487/1983, Japanese Patent Application No. 1961065/1976 and the like can be mentioned.

In these newly proposed lifting mechanisms,
The three-tiered booms extend in the length direction, and X
It is configured such that the middle booms whose central portions are connected to each other by a shaft in a letter shape rotate with respect to each other so that the vehicle body and the lifting platform have an X shape when viewed from the side. In this structure, the lower boom and the upper boom extend the length of the middle boom, respectively, so that the lifting platform can be raised to a higher position. Further, since the respective tips of the lower boom and the upper boom are connected to the vehicle body or the lifting platform by pins, there is little rattling, and the boom can be firmly held against shaking.

In the elevating mechanism using the telescopic boom body which can be expanded and contracted in a plurality of stages, in order to extend and retract the lower boom and the upper boom from the middle boom, the hydraulic pressure interposed between the vehicle body and the center of the middle boom is used. A configuration was adopted in which the middle boom itself was lifted by a cylinder, or the lower boom or the upper boom was pushed out by a hydraulic cylinder inserted in the middle boom to extend the boom.

In this structure, since the hydraulic cylinder must be used to lift the middle boom and extend the lower boom and the upper boom, the extension amounts of the upper boom and the lower boom must be synchronized. is there. For this synchronization, a tuning mechanism composed of a chain, a wire, or the like must be provided, which complicates the structure, complicates the assembling, and has a drawback that the lifting mechanism itself is heavy.

Since such conventional aerial work vehicles have their respective drawbacks, the hydraulic expansion / contraction mechanism itself in the lifting mechanism has a structure similar to that of the hydraulic cylinder, and the rods are respectively retracted from both ends of the hydraulic expansion / contraction mechanism. Is also proposed. However, in the outer shell in which the hydraulic cylinders are combined vertically or horizontally, the mechanism is exposed to the outside, which not only looks bad, but also causes the connecting portion to project and catch the overhead wire or wire, which causes an accident. Moreover, since the hydraulic pipe is exposed to the outside, assembly and maintenance are troublesome.

[0017]

SUMMARY OF THE INVENTION The present invention provides an aerial work vehicle that overcomes the above-mentioned drawbacks. The entire cylinder body constituting the hydraulic expansion / contraction mechanism is formed as an outer shell of an integrated hydraulic cylinder, and the rods are respectively retracted in the opposite direction from the cylinder body. With this configuration, the appearance of the cylinder body is simple and the piping and the like are not exposed, so that assembly and maintenance are easy. Further, since the structure is not simply a combination of hydraulic cylinders, the protrusion is not exposed to the outside, and the overhead wire or the wire is not caught, so that an accident can be prevented.

[0018]

SUMMARY OF THE INVENTION The present invention is directed to a movable vehicle body, an elevating table which is located above the vehicle body and can be vertically moved up and down, and an elevating mechanism which is interposed between the vehicle body and the elevating table and can be vertically expanded and contracted. In an aerial work vehicle having a hydraulic lifting mechanism, the lifting mechanism is composed of at least a pair of hydraulic expansion and contraction mechanisms, and the hydraulic expansion and contraction mechanisms are rotatably connected to each other at their centers to be combined into an X-shaped hydraulic expansion and contraction mechanism. Each of them consists of an elongated cylinder body and a pair of rods that can project in and out from both ends of this cylinder body in parallel in opposite directions.One rod of each hydraulic expansion mechanism is connected to the vehicle body, and the other rod is raised and lowered. An aerial work vehicle characterized by being connected to a platform.

[0019]

In the present invention, the elevating mechanism is composed of a pair of hydraulic expansion / contraction mechanisms combined in an X shape, and each hydraulic expansion / contraction mechanism is composed of an integrally formed cylinder body. Since this cylinder body can be manufactured by casting, drawing or the like, it is easy to manufacture, and is easy to assemble and maintain. This cylinder body has a structure similar to multiple hydraulic cylinders, and rods are slidably inserted from both ends of this cylinder body. Therefore, when each rod extends, the lifting mechanism expands into an X shape and the lifting platform moves up and down. Can be moved to. Also, by setting the pressure cross-sectional area applied to each rod of each cylinder body to a specific relationship, the extension amount of each rod can be synchronized, and the lifting platform can be vertically maintained while always maintaining the horizontal state. Can be raised.

[0020]

An embodiment of the present invention will be described below with reference to the drawings. In this embodiment, FIG. 1 is a perspective view of the elevation platform of a work platform elevated to a maximum height position as viewed from the rear, and FIG. 2 is a perspective view of the platform platform raised to the maximum height. FIG. 3 is a side view showing a state where the lifting platform is lowered to the minimum height, and FIG. 4 is a rear view showing a state where the lifting platform is lowered to the minimum height.

First, in these figures, a front wheel 2 and a rear wheel 3 are axially supported at the front and rear of the lower portion of a vehicle body 1 having a prime mover, a hydraulic pressure generating mechanism and the like built therein. The front wheel 2 can change its direction to the left and right, and the vehicle body 1 can freely move its position by driving the rear wheel 3. An elevating mechanism 4 assembled in an X shape on the upper surface of the vehicle body 1.
Is connected to the upper end of the elevating mechanism 4, and an elevating table 5 for mounting people and materials is connected. This elevator 5
A handrail 6 made of pipe is fixed around the upper surface of the pipe so that the worker does not drop. A control box 7 is provided on the front surface of the handrail 6 for storing operation levers, switches and the like, and for operating the entire work platform for aerial work.
Is fixed. Further, two sets of kick mechanisms 8 are provided on the left and right of the center of the upper surface of the vehicle body 1 and are composed of gas springs and are always urged upward.

Next, the elevating mechanism 4 comprises two sets of hydraulic expansion / contraction mechanisms 11 and 12 arranged on the left and right of the vehicle body 1. These hydraulic expansion / contraction mechanisms 11 and 12 are combined in a pair and rotatably connected at the center thereof to form an X shape. These hydraulic expansion / contraction mechanisms 11 and 12
Has exactly the same structure, but with hydraulic expansion / contraction mechanisms 11 and 1
Both of the two are vertically inverted in the structure. That is, the hydraulic expansion / contraction mechanism 11 has a cylinder body 13 as a skeleton, and the cylinder body 13 is integrally formed of, for example, an aluminum casting or a light alloy casting. Further, the hydraulic expansion / contraction mechanism 12 has a cylinder body 14 as a skeleton, and the cylinder body 14 is integrally formed of, for example, a casting made of a light alloy such as aluminum or duralumin.

A thick rod 15 having a large outer diameter is arranged in the lower portion of the cylinder body 13, and a thin rod 16 having a small outer diameter is arranged in the upper portion thereof so as to be vertically parallel to each other. The rod 16 is inserted so as to be slidable with respect to the cylinder body 13. Also, the cylinder body 1
In Fig. 4, a thin rod 18 having a small outer diameter is combined with a lower portion thereof, and a thick rod 17 having a large outer diameter is combined with an upper portion thereof in a vertically parallel manner.
8 is inserted so as to be slidable with respect to the cylinder body 14. The thick rods 15 and the thin rods 16 are capable of expanding and contracting in opposite directions, the thick rods 17 and the thin rods 18 are capable of expanding and contracting in opposite directions, and the cylinder bodies 13 and 14 are respectively It has a structure similar to a hydraulic cylinder with two cylinders.

Further, kick pins 29 and 30 are horizontally projected and fixed to the centers of the side surfaces of the respective cylinder bodies 13 and 14, and these kick pins 29 and 30 contact the upper end of the kick mechanism 8, This assists the initial lifting of the lifting mechanism 4.

A shaft support 21 is fixed to the front of the upper surface of the vehicle body 1 (on the left side in FIGS. 1, 2, and 3), and the rear portion of the upper surface of the vehicle body 1 (in FIGS. 1, 2, and 3). The shaft support 22 is fixed to the right side). A shaft support 23 is fixed to the front of the lower surface of the lifting table 5, and a shaft support 24 is fixed to the rear of the lower surface of the lifting table 5. These shaft supports 2
Each of 1, 22, 23, and 24 is formed by bending a thin steel plate, and has a slightly trapezoidal block-shaped structure. The distance between the shaft support members 21 and 22 and the distance between the shaft support members 23 and 24 are arranged to be substantially the same. Then, the connecting ring at the tip of the thick rod 15 is inserted into the shaft support 21, and the thick rod 15 and the shaft support 21 are inserted.
Are rotatably connected by a pin 25. Also,
A connecting ring at the lower end of the thin rod 18 is inserted into the shaft support 22, and the thin rod 18 and the shaft support 22 are rotatably connected by a pin 26. Similarly, the connecting ring at the tip of the thick rod 17 is inserted into the shaft support 23,
The thick rod 17 and the shaft support 23 are rotatably connected by a pin 27. Further, the shaft support 24 has a thin rod 16
The connecting ring at the tip of is inserted, and the thin rod 16 and the shaft support 24 are rotatably connected by a pin 28. The shaft support 21 and the shaft support 22 are fixed at positions deviated to the left and right with respect to the central axis of the vehicle body 1.
Similarly, 3 and the shaft support 24 are also fixed to the lower surface of the lifting table 5 at positions laterally offset with respect to the central axis.

Next, FIG. 5 shows a structure 2 of the lifting mechanism 4.
The internal structure of one of the hydraulic expansion / contraction mechanisms 11 and 12 is shown. The cross-sectional structure of this hydraulic expansion / contraction mechanism 11 is the same as that of the hydraulic expansion / contraction mechanism 12,
The other hydraulic expansion / contraction mechanism 12 has a structure obtained by vertically inverting the structure shown in FIG. Although the description of the structure of the hydraulic expansion / contraction mechanism 12 is omitted, the structure is exactly the same as the structure of the hydraulic expansion / contraction mechanism 11 shown in FIG.

In FIG. 5, the cylinder body 13 is an elongated one piece having a slightly rectangular cross section,
A thick deep hole 37 having a large diameter is bored from one end (left side in FIG. 5) in the length direction, and a thin deep hole 37 is bored in the length direction from the other end (left side in FIG. 5). A deep hole 38 having a diameter is drilled. Each deep deep hole 37 and the narrow deep hole 38 have a structure in which the innermost part is closed, and a pipe-shaped liner 39 is attached inside the thick deep hole 37, and inside the narrow deep hole 38. A pipe-shaped liner 40 is attached. The outer diameter of the liner 39 is set to be substantially the same as the inner diameter of the thick deep hole 37, and the outer diameter of the liner 40 is set to be substantially the same as the inner diameter of the narrow deep hole 38. The liners 39 and 40 are made of wear-resistant steel pipe or the like, and are made of a material that does not wear even after long-term use. And thick hole 3
7. The deep holes 38 are arranged so that their axes are parallel to each other, which is set so that the liners 39 and 40 are parallel to each other.

In such a cylinder body 13, a sliding cap 41 having an opening at the center is fixed by a screw 43 at the opening end (right side in FIG. 5) of the thick deep hole 37, and the deep deep hole 38 is formed. A sliding cap 42 having an opening formed in the center is fixed to the opening end (left side in FIG. 5) with a screw 44. Inside the liner 39, the piston 4 having an outer diameter substantially equal to the inner diameter of the liner 39 is provided.
5 is slidably and airtightly inserted, and the piston 45 divides the inside of the liner 39 into two parts.
A thick rod 15 having a pipe shape is slidably and airtightly inserted from the opening of the sliding cap 41. A screw is formed at the end of the thick rod 15, and after inserting this screw into an opening opened in the center of the piston 45, a nut 47 is screwed into this screw so that the piston 45 comes to the end of the thick rod 15. It's stuck. In addition, thick rod 1
A connecting ring 49 for connecting a pin is fitted and fixed to the tip of the pin 5. Also, inside the liner 40,
A piston 46 having an outer diameter substantially equal to the inner diameter of the liner 40 is slidably and airtightly inserted, and the piston 46 divides the inside of the liner 40 into two parts. The pipe-shaped thin rod 16 is slidably and airtightly inserted from the opening of the sliding cap 42. A screw is formed at the end of the thin rod 16,
After inserting this screw into an opening formed in the center of the piston 46, a nut 48 is screwed into this screw, whereby the piston 46 is fixed to the end of the thin rod 16. In addition,
A coupling ring 50 for pin coupling is fitted and fixed to the tip of the thin rod 16. With such a configuration, the cylinder body 13 has a structure substantially similar to the two hydraulic cylinders.

FIG. 6 shows the relationship between the cross-sectional shape of the cylinder body 13 and the liners 39, 40 and the thick rod 15 in the hydraulic expansion / contraction mechanism 11. FIG. 6 shows a cross section taken along line XX in FIG. Oil guide holes 51 and 52 are formed on the left and right sides of the cylinder body 13, and the oil guide holes 51 and 52 are formed in the thick deep hole 37 and the thin deep hole 3 respectively.
It is installed at a certain distance from No. 8. Then, in FIG. 6, the cross-sectional area A of the space formed by the inner circumference of the liner 39 and the outer circumference of the thick rod 15 is made to coincide with the cross-sectional area B of the space formed by the inner circumference of the liner 40.

Further, FIG. 7 shows a connection state of pipes inside the cylinder body 13. The cylinder body 13 is shown by a chain line, and the oil guide holes 51, 52, 5
3, 54 are shown by solid lines. As described above, the four oil guide holes 51, 52, 53, 54 are formed in the cylinder body 13 from the center to both ends, and each of them is independent. One end of the oil guide hole 51 communicates with the discharge side inside the liner 39, and the other end communicates with a port 55 fixed to the side surface of the cylinder body 13 near the center. One end of the oil guide hole 52 communicates with the pressure side inside the liner 40, and the other end communicates with a port 56 fixed to the side surface of the cylinder body 13 near the center.
One end of the oil guide hole 53 communicates with the pressure side inside the liner 39, and the other end communicates with a port 57 fixed to the side surface of the cylinder body 13 near the center. Oil guide hole 5
One end of 4 is communicated with the discharge side inside the liner 40, and the other end is communicated with a port 58 fixed to the side surface of the cylinder body 13 near the center.

Next, FIG. 8 shows the pair of hydraulic expansion / contraction mechanisms 11, 12 in FIG. 1, that is, the cylinder bodies 13, 14.
3 shows the internal structure of a rotation mechanism 35 for connecting the two so that they can rotate and cannot be disengaged from side to side.

In this rotating mechanism 35, the cylinder body 13
An outer fixing ring 61 having a circular opening inside is fixed to the inner side surface of the cylinder, and a cylindrical inner fixing ring 62 is fixed to the inner side surface of the cylinder body 14. The outer fixing ring 61 and the inner fixing ring 62 each have a cylindrical shape, and the outer diameter of the inner fixing ring 62 is set to be slightly smaller than the inner diameter of the outer fixing ring 61. The entire inner fixing ring 62 has a cap-like shape at the tip thereof, and the outer peripheral end of the inner fixing ring 62 expands outward to form a flange-like shape.
3 is covered. A cylindrical sliding body 66 made of a slippery material such as MC nylon is inserted through the outer circumference of the inner cap 63, and the inner diameter of the sliding body 66 is substantially the same as the outer diameter of the inner cap 63. The outer diameter thereof is set to be substantially the same as the inner diameter of the outer fixing ring 61. A disc-shaped pressing plate 64 having an outer diameter slightly larger than the inner diameter of the sliding body 66 is closely attached to the side surface of the inner cap 63. The inner cap 63 and the pressing plate 64 are fastened to the inner fixing ring 62 with bolts 65. It is fixed. Further, on the side surface of the outer fixing ring 61, a cylindrical outer cap 67 whose end ends are enlarged in a flange shape inside and outside, respectively.
Are closely attached to each other, and the outer cap 67 is screwed to the outer fixing ring 61 by a bolt 62. The inner diameter of the outer cap 67 is set to be substantially the same as the outer diameter of the sliding body 66. The sliding body 66 has a flange protruding at the outer peripheral end of the inner cap 63, the side surface of the outer fixing ring 61, and the outer cap 67. It is fitted and fixed by a flange protruding from the inner peripheral edge. Due to this structure, the sliding body 66 is made of a slippery material. Therefore, when the inner fixing ring 62, the inner cap 63, and the holding plate 64 rotate simultaneously, the outer fixing ring 61 and the outer cap 67 relatively rotate. , Sliding body 6
Since 6 acts as a lubricant, the outer fixing ring 61 and the inner fixing ring 62 have no play and are held so that they can slide smoothly.

Next, FIG. 9 shows the lifting mechanism 4 in this embodiment.
3 shows the situation of the pipe connection between the hydraulic expansion / contraction mechanisms 11 and 12 when assembled.

In this case, one end of a hydraulic hose 76 is connected to the port 55 which communicates with the discharge side of the thick liner 39 formed in the cylinder body 13.
The other end of the hydraulic hose 76 is connected to the port 72 which communicates with the pressure side of the thin liner 40 formed in the above. One end of a hydraulic hose 77 is connected to the pressure side port 56 of the large diameter liner 40 formed in the cylinder body 13, and the discharge side port 71 of the thin diameter liner 39 of the cylinder body 14 is connected to the above. The other end of the hydraulic hose 77 is connected. A pipe for making the two cylinder bodies 13 and 14 intersect each other forms a synchronous circuit for vertically extending the elevating mechanism 4.

Next, FIG. 10 shows a hydraulic circuit in this embodiment.

A hydraulic pump 78 is connected to a prime mover 79 such as a motor and an engine built in the vehicle body 1, and an oil tank 80 storing pressure oil is connected to the suction side of the hydraulic pump 78. A switching valve 81 for switching circuits in three directions is connected to the discharge side of the hydraulic pump 78. The return side of the switching valve 81 is communicated with the oil tank 80. The port 57 and the port 73 are connected in parallel to one side of the switching valve 81, and the port 58 and the port 73 are connected to the other side of the switching valve 81.
And port 74 are connected in parallel. As described above, the port 55 and the port 72 are connected by the hydraulic hose 76, and the port 56 and the port 71 are connected by the hydraulic hose 77.

Next, the operation of this embodiment will be described.

First, in order to operate this aerial work vehicle, the prime mover 79 housed in the vehicle body 1 is started by a battery or gasoline, and the prime mover 79 drives the hydraulic pump 78. This hydraulic pump 78 is an oil tank 80
It can be operated by sucking more pressure oil and supplying the pressure oil to each part of the aerial work vehicle. The operation of this aerial work vehicle is performed by a worker who has boarded the elevator 5 operating a lever or the like of the control box 7.

First, to extend the elevating table 5 to the maximum height as shown in FIG. 2 from the state where the elevating table 5 is lowered to the lowest position as shown in FIG. 3, the switching valve 81 is set to "the positive side". Switch to. Then, the pressure oil supplied from the hydraulic pump 78 is simultaneously supplied to the port 57 and the port 73 via the respective oil passages. The pressure oil supplied from the port 57 through the oil guide hole 53 into the liner 39 pushes the piston 45 in FIG. 5 to the left in the drawing, causing the thick rod 15 to move from the opening of the sliding cap 41 to the cylinder body 13. Acts to push it out of the. Similarly, in the cylinder body 14, the thick rod 17 is also pushed out by the pressure oil supplied to the port 73. Therefore, the thick rod 15 and the thick rod 17 are simultaneously pushed out from the cylinder bodies 13 and 14, respectively, and the total length of the cylinder body 13 and the thick rod 15 and the total length of the cylinder body 14 and the thick rod 17 become long.

As described above, when the pressure oil is supplied to the ports 57 and 73, the piston 45 moves in the liner 39, so that it is stored in the space on the left side of the liner 39 divided by the piston 45 in FIG. The pressure oil that was used was in ports 55 and 7.
1 is discharged at the same time. The pressure oil discharged from the port 55 is transmitted to the port 72 via the hydraulic hose 76 and is supplied to the pressure side of the thin liner 40. Also,
The pressure oil discharged from the port 71 is transmitted to the port 56 via the hydraulic hose 77 and is supplied to the thin liner 40. When the pressure oil is supplied into the thin liner 40 in this way, the piston 46 in the liner 40 is moved to the right side in FIG.
It will be pushed out from the opening of the sliding cap 42 of Nos. 3 and 14. Therefore, the thin rods 16 and 18 are simultaneously pushed out from the cylinder bodies 13 and 14, respectively, and the total length of the cylinder body 13 and the thin rod 16 and the total length of the cylinder body 14 and the thin rod 18 become long.

As shown in FIG. 6, the cross-sectional area A of the discharge-side annular space in the large-diameter liner 39 is the same as the pressure-side cross-sectional area B of the thin-diameter liner 40.
Therefore, if the amount of hydraulic pressure supplied to each of the cross-sectional areas A and B is the same, the thick rod 1 pushed out from the cylinder body 13
5 and the movement amount of the thin rod 18 pushed out from the cylinder body 14 are the same. Similarly, the movement amount of the thick rod 17 pushed out from the cylinder body 14 and the movement amount of the thin rod 16 pushed out from the cylinder body 13 match. Then, the cylinder bodies 13 and 14
The movement amounts of the thick rods 15 and 17 and the thin rods 16 and 18 that are respectively pushed out are the same. By such interlocking, the hydraulic expansion / contraction mechanisms 11 and 12 are rotated by the rotation mechanism 35.
It will be extended with the same amount of extension in a radial fashion centering around each.

However, the tips of the thick rods 15 and 17 and the thin rods 16 and 18 have shaft supports 21 and 22,
23 and 24, the hydraulic expansion / contraction mechanism 11,
In the state of FIG. 3 in which 12 are arranged in parallel, the extension force does not act on the lifting platform 5. However, since the kick mechanism 8 is always biased upward and the kick pins 29 and 30 are in contact with the upper surface of the kick mechanism 8, the kick mechanism 8 biases the kick pins 29 and 30 upward. Therefore, the kick mechanism 8 causes the hydraulic expansion / contraction mechanism 1 to move.
Nos. 1 and 12 are lifted slightly upward, and are transformed into a deformed X-shape that is crushed from above and below. At this time, in the rotating mechanism 35,
Since the cylindrical slidable body 66 having lubricity at the center is sandwiched between the outer fixed ring 61 and the inner fixed ring 62, the outer fixed ring 61 and the inner fixed ring 62 smoothly rotate in the circumferential direction. To hold. Therefore, the hydraulic expansion / contraction mechanism 11 and the hydraulic expansion / contraction mechanism 12 rotate relatively in opposite directions and do not prevent the cylinder bodies 13 and 14 from becoming X-shaped.

When the hydraulic expansion / contraction mechanism 11 and the hydraulic expansion / contraction mechanism 12 are slightly changed to the X-shape in this way, the cylinder body 13,
Thick rods 15 and 17 extruded from 14 and thin rod 1
The extension force of 6 and 18 becomes a component force in the vertical direction, and acts to lift the lifting platform 5 upward. In this way, the hydraulic expansion / contraction mechanism 11 and the hydraulic expansion / contraction mechanism 1 configuring the lifting mechanism 4
2 becomes an X-shape in which the upper and lower sides are collapsed from a state of being folded in parallel, and then changes to an X-shape, and the lifting platform 5 is extended to the maximum and rises to the state shown in FIGS. 1 and 2.

The pressure oil discharged from the ports 58, 74 on the discharge side of the thin liner 40 returns to the switching valve 81 and is collected by the oil tank 80.

In this order, the cylinder body 1
In 3 and 14, the distance between the ends of the thick rod 15 and the thin rod 16 and the distance between the ends of the thick rod 17 and the thin rod 18 are
The length of the cylinder bodies 13 and 14 is extended to about three times. As a result, the lift 5 is lifted to a position higher than the vehicle body 1. If the lifting table 5 is lifted to a predetermined height and the worker holds the switching valve 81 at the "neutral" position, the pressure oil supplied to the pressure side of the liner 39 stops its flow, and the lifting table 5 is lifted. 5 will be maintained in its height position. By maintaining this state, the worker on the lift 5 can perform various works at high places.

In order to lower the lifting table 5, the switching valve 81 is switched to the "reverse" side, contrary to the above, to supply the pressure oil to the ports 58 and 74. Then, the pressure oil flows in the opposite direction to the above, flows into the thin liner 40, moves the piston 46 leftward in FIG. 5, and moves the thin rod 16 into the cylinder body 13 and the thin rod 18 into the cylinder body 13. It acts to retract into the cylinder body 14. This piston 46
Of the liner 40, the pressure oil in the space on the left side of the liner 40 in FIG. 5 is discharged from the port 56. In this way, the pressure oil discharged from the port 56 is transferred to the hydraulic hose 77 and the port 7.
1 is supplied to the discharge side space of the large diameter liner 39, and at the same time, the pressure oil discharged from the port 72 is supplied to the discharge side space of the large diameter liner 39 via the hydraulic hose 76 and the port 55. It Therefore, the thick rods 15 and 1
7. The thin rods 16 and 18 are liners 39 and 40, respectively.
Be drawn in. Therefore, the distance between the tips of the thick rod 15 and the thin rod 16, and the thick rod 17 and the thin rod 1
The distance between the tips of 8 is reduced, and the thick rod 15,
The movement amounts of 17, and the thin rods 16 and 18 are synchronized. Then, the elevating mechanism 4 reduces its height while maintaining the X-shape, and the elevating table 5 gradually descends toward the vehicle body 1. Then, finally, the kick pins 29, 30 come into contact with the upper end of the kick mechanism 8, and the elevating mechanism 4 compresses the kick mechanism 8 until the thick cylinders 13, 15 and the thin cylinders 14, 16 become parallel. Be folded. In this way, the state in which the lifting table 5 is extended as shown in FIG. 2 is changed to the state in which the lifting table 5 is placed on the upper surface of the vehicle body 1 as shown in FIG.

Next, FIG. 11 shows another embodiment of the present invention. The hydraulic expansion / contraction mechanisms 11 and 12 constituting the lifting mechanism 85 in this embodiment have exactly the same structure as the first embodiment described in FIG.

In this embodiment, the hydraulic expansion / contraction mechanisms 11 and 12 are used.
Each of the cylinder bodies 13 and 14 constituting the above is configured such that its longitudinal plane is arranged in the horizontal direction. The thick rod 15 of the cylinder body 13 and the thin rod 18 of the cylinder body 14 are arranged outside the vehicle body 1, and the thin rod 16 of the cylinder body 13 and the thick rod 17 of the cylinder body 14 are arranged.
Are located close to each other inside. Even with this configuration, the internal structure of each hydraulic expansion / contraction mechanism 11 and 12 and the hydraulic piping are the same as in the first embodiment in FIG. 1, and the thick rods 15 and 17 and the thin rods 16 and 18 are synchronized. It is possible to move the lift table 5 up and down while expanding and contracting at the same speed. In this structure, the thick rod 15 and the thin rod 18 are arranged on the outer side in a plane, so that the stability is improved. The kick mechanism 8 is omitted in FIG.

FIG. 12 shows a third embodiment of the present invention. The lifting mechanism 86 in this embodiment is composed of three sets of hydraulic expansion / contraction mechanisms 87, 88, 89.
The structures of these hydraulic expansion / contraction mechanisms 87 and 88 are the same as the hydraulic expansion / contraction mechanism 11 in FIG. 1, and the structures of the hydraulic expansion / contraction mechanism 89 are the same as the hydraulic expansion / contraction mechanism 12 in FIG.

The hydraulic expansion / contraction mechanisms 87 and 88 are respectively formed of cylinder bodies 90 and 91 integrally formed of a light alloy such as aluminum and magnesium. The cylinder bodies 90 and 91 have opposite ends. The thicker rods 93, 95 and the thinner rods 94, 95 are housed so that they can slide in parallel. These thick rods 93
The thin rod 94 and the thin rod 94 are directed in opposite directions from the cylinder body 90, and the thick rod 94 and the thin rod 95 are oriented in opposite directions from the cylinder body 91, respectively. Further, the hydraulic expansion / contraction mechanism 89 is formed of a cylinder body 82 integrally formed of a light alloy such as aluminum or magnesium, and the main body thereof is formed.
A thick rod 97 and a thin rod 98 are housed so as to be slidable in parallel and in opposite directions from both ends of 2.

In addition, on the front side of the upper surface of the vehicle body 1 (left side in FIG. 12), shaft support members 99 and 100 are fixed at intervals and at the center of the rear side (right side in FIG. 11) of the upper surface of the vehicle body 1. A shaft support 101 is fixed to the shaft. The shaft support 99 and the tip of the thick rod 93 are connected by a pin 105, the shaft support 100 and the tip of the thick rod 95 are connected by a pin 100, and the shaft support 101 and the thin rod 98 are connected. The tip is connected by a pin 107. Further, shaft supporting members 102 and 103 are fixed to the rear side of the lower surface of the lifting table 5 at intervals, and the shaft supporting member 1 is provided at the center of the front side of the lower surface of the lifting table 5.
04 is stuck. This shaft support 102 and thin rod 94
It is connected to the tip of the shaft by a pin 108, and
03 and the tip of the thin rod 96 are connected by a pin 109, and the shaft support 104 and the tip of the thick rod 97 are connected by a pin 110. In this way, the vehicle body 1, the lifting mechanism 86, and the lifting platform 5 are configured to be X-shaped when viewed from the side, and the lifting platform 5 includes three sets of hydraulic expansion and contraction mechanisms 8.
It will be strongly supported by 7, 88 and 89.

Next, FIG. 13 shows a hydraulic circuit in the embodiment of FIG. In this configuration, the cross-sectional area on the pressure side of the thin rod 98 of the hydraulic expansion / contraction mechanism 89 in the center is equal to the thick rods 93, 95 of the hydraulic expansion / contraction mechanisms 87, 88 on both sides.
It is set to be almost the same as the total cross-sectional area on the discharge side. In addition, the cross-sectional area of the hydraulic expansion / contraction mechanism 89 on the discharge side of the thick rod 97 is equal to that of the thin rods 9 of the hydraulic expansion / contraction mechanisms 87, 88 on both sides.
It is set to be almost the same as the total of the sectional areas on the pressure side of 4, 96. On the “positive” side of the switching valve 81, thick rods 93, 95,
97 is connected to the pressure side, and the "reverse" side of the switching valve 81 is connected to the discharge side of the thin rods 94, 96, 98.
The discharge side of the thick rods 93 and 95 and the pressure side of the thin rod 98 are connected by the same oil passage, and the pressure side of the thin rods 94 and 96 and the discharge side of the thick rod 97 are connected by the same oil passage. .

In the third embodiment, when the switching valve 81 is switched to the "normal" side, the pressure oil from the hydraulic pump 78 is supplied to the pressure side of the thick rods 93, 95, 97, and the thick rods 93, 95, 97 are cylinder bodies 90, 91,
Extruded from 92. At the same time, the total pressure oil pushed out from the discharge sides of the thick rods 93 and 95 is supplied to the pressure side of the thin rod 98, and acts to push the thin rod 98 out of the cylinder body 92. Further, the pressure oil pushed out from the discharge side of the thick rod 97 is distributed and supplied to the pressure side of the thin rods 94, 96, and acts to push out the thin rods 94, 96 from the cylinder bodies 90, 91. As described above, since the pressure cross-sectional areas of the thick rods 93, 95, 97 and the thin rods 94, 96, 98 are set to be synchronized with each other, the thick rods extending from the respective cylinder bodies 90, 91, 92 are extended. The extension amounts of the thin rods 93, 95, 97 and the thin rods 94, 96, 98 are the same, and the elevating mechanism 86 forms an X shape and radially expands, so that the elevating table 5 can be lifted vertically upward with respect to the vehicle body 1. it can.

Further, FIG. 14 shows a fourth embodiment of the present invention. In this embodiment, four sets of lifting mechanisms 120 are interposed between the vehicle body 1 and the lifting table 5. Car body 1
The combination of the hydraulic expansion / contraction mechanisms 121 and 122 and the combination of the hydraulic expansion / contraction mechanisms 123 and 124 are arranged in parallel on the left and right of the upper part of the.
They are arranged in pairs. These two sets of hydraulic expansion / contraction mechanism 121,
122 and the hydraulic expansion / contraction mechanisms 123 and 124 have the same configuration as the two sets of hydraulic expansion / contraction mechanisms 11 and 12 described with reference to FIG.
Although the arrangement is the same as that of 12, the hydraulic expansion / contraction mechanisms 123, 12
4 is an arrangement in which the hydraulic expansion / contraction mechanisms 11 and 12 are reversed. Therefore, the cylinder body 12 of the hydraulic expansion / contraction mechanism 121.
5 and the cylinder body 127 of the hydraulic expansion / contraction mechanism 123 are arranged so as to be parallel to the left and right outer sides.
The cylinder body 126 and the cylinder body 128 of the hydraulic expansion / contraction mechanism 124 are arranged so as to be parallel to each other in the center of the vehicle body 1.

In this structure, the lifting table 5 is supported by four sets of hydraulic expansion / contraction mechanisms 121, 122, 123, and 124, and the lifting mechanism 120 is connected to the vehicle body 1 and the lifting table 5 at four points, respectively. Extremely stable. Also,
Since the hydraulic expansion / contraction mechanisms 121, 122, 123, and 124 perform the ascending action evenly, the lifting platform 5 can be strongly lifted and the durability against a load is high.

[0056]

Since the present invention is constructed as described above, the lifting mechanism can be composed of a plurality of hydraulic expansion / contraction mechanisms similar to a hydraulic cylinder, and the structure is extremely simple. By making the pressure cross-sectional areas of these thick cylinders and thin cylinders the same, the speeds of the thick rods and thin rods that expand and contract from them can be synchronized.

Since the hydraulic expansion / contraction mechanism constituting the lifting mechanism can have the same structure as the hydraulic cylinder by the cylinder body integrated with casting or the like, the appearance is extremely simplified. For this reason, unnecessary projections are eliminated, and overhead wires and wires are not hooked. Also, since the hydraulic pipe can be formed in the cylinder body, it is not necessary to expose the pipe such as the pipe,
It is easy to assemble and inspect.

[Brief description of drawings]

FIG. 1 is a perspective view showing an entire aerial work vehicle according to an embodiment of the present invention.

FIG. 2 is a side view showing a state in which a lifting platform of an aerial work vehicle is lifted to a maximum height position.

FIG. 3 is a side view showing a state in which the lifting platform of the aerial work vehicle is lowered to the lowest height position.

FIG. 4 is a rear view showing a state in which the lifting platform of the aerial work vehicle is lowered to the lowest height position.

FIG. 5 is a cross-sectional view showing the structure of a pair of hydraulic expansion / contraction mechanisms that constitute the lifting mechanism.

6 is a cross-sectional view of the hydraulic expansion / contraction mechanism in FIG. 5 as seen in the direction of arrows XX.

FIG. 7 is an explanatory diagram showing piping in a cylinder body in the hydraulic expansion / contraction mechanism.

FIG. 8 is a vertical cross-sectional view showing a rotation mechanism that connects two sets of hydraulic expansion / contraction mechanisms.

FIG. 9 is an explanatory diagram showing a pipe connection of two hydraulic expansion / contraction mechanisms.

FIG. 10 is a hydraulic circuit diagram in the present embodiment.

FIG. 11 is a perspective view showing an entire aerial work vehicle according to a second embodiment of the present invention.

FIG. 12 is a perspective view showing an entire aerial work vehicle of a third embodiment of the present invention.

FIG. 13 is a hydraulic circuit diagram in the third embodiment.

FIG. 14 is a perspective view showing an entire aerial work vehicle according to a fourth embodiment of the present invention. DESCRIPTION OF SYMBOLS 1 Vehicle body 4 Lifting mechanism 5 Lifting platform 11 Hydraulic expansion / contraction mechanism 12 Hydraulic expansion / contraction mechanism 13 Cylinder body 14 Cylinder body 15 Thick rod 16 Thin rod 17 Thick rod 18 Thin rod 35 Rotating mechanism 85 Lifting mechanism 86 Lifting mechanism 87 Hydraulic stretching mechanism 88 Hydraulic Expansion / contraction mechanism 89 Hydraulic expansion / contraction mechanism 90 Cylinder body 91 Cylinder body 92 Cylinder body 93 Thick rod 94 Thin rod 95 Thick rod 96 Thin rod 97 Thick rod 98 Thin rod 120 Lifting mechanism 121 Hydraulic expansion / contraction mechanism 122 Hydraulic expansion / contraction mechanism 123 Hydraulic expansion / contraction mechanism 124 Hydraulic pressure Expansion and contraction mechanism 125 Cylinder body 126 Cylinder body 127 Cylinder body 128 Cylinder body

Claims (14)

[Claims] 1. An aerial work vehicle having a movable vehicle body, an elevating platform that is located above the vehicle body and can be vertically moved up and down, and an elevating mechanism that is interposed between the vehicle body and the vertically movable platform and can be vertically expanded and contracted. The lifting mechanism is composed of at least a pair of hydraulic expansion / contraction mechanisms, and the central parts of both hydraulic expansion / contraction mechanisms are rotatably connected to each other so that the lifting / lowering mechanism has an X-shape. Each hydraulic expansion / contraction mechanism has an elongated cylinder. It is composed of a body and a pair of rods that can project in and out from both ends of the cylinder body in parallel in opposite directions.One rod of each hydraulic expansion mechanism is connected to the vehicle body, and the other rod is connected to the lifting platform. And aerial work vehicles. 2. The end of one rod of one hydraulic expansion / contraction mechanism is connected to one side of the vehicle body, the end of the other rod of one hydraulic expansion / contraction mechanism is connected to the other of the lifting platform, and the other hydraulic expansion / contraction mechanism is connected to the other of the hydraulic expansion / contraction mechanisms. The tip of the rod is connected to the other side of the vehicle body, the tip of the rod of the other hydraulic expansion and contraction mechanism is connected to one of the elevators, and the connection interval between the pair of rods on the vehicle body and the connection interval between the pair of rods on the elevator table is adjusted. Claim 1 characterized in that they are substantially the same.
The aerial work vehicle described. 3. The aerial work vehicle according to claim 1, wherein rods of the hydraulic expansion / contraction mechanisms are arranged vertically. 4. The aerial work vehicle according to claim 1, wherein rods of the respective hydraulic expansion / contraction mechanisms are arranged on the left and right. 5. A pair of deep holes opened at both ends are bored in parallel in each cylinder body, and pistons that slide in an airtight manner are accommodated in each deep hole, and each rod inserted from each opening is respectively inserted. The aerial work vehicle according to claim 1 or 2, which is connected to a piston. 6. A high-place work according to claim 5, wherein a cylindrical liner is housed in each deep hole of each cylinder body, and a piston that slides airtightly in each liner is housed therein. car. 7. A deep hole of each cylinder body is formed to have a large diameter and a small diameter, and the tip of a rod inserted into the deep hole of one cylinder body is connected to one of the vehicle bodies and the other cylinder body is connected. Connect the tip of the rod inserted into the small-diameter deep hole to the other side of the vehicle body, connect the tip of the rod inserted into the small-diameter deep hole of one cylinder body to the other side of the lifting platform, and connect the thick end of the other cylinder body. 7. An aerial work vehicle according to claim 5, wherein the tip of the rod inserted into the deep hole of the diameter is connected to one of the elevating tables. 8. A cross-sectional area obtained by subtracting the cross-sectional area of the outer diameter of the rod inserted into this deep hole from the cross-sectional area of the large-diameter deep hole of each cylinder body on the pressure side of the narrow deep hole. Set the cross-sectional area to be almost the same, and connect the discharge side of the large-diameter deep hole of one cylinder body to the pressure side of the small-diameter deep hole of the other cylinder body, and connect the large-diameter deep hole of the other cylinder body. 8. The aerial work vehicle according to claim 7, wherein the discharge side of the cylinder and the pressure side of the small-diameter deep hole of the one cylinder body are communicated with each other. 9. An aerial work vehicle having a movable vehicle body, an elevating platform that is located above the vehicle body and can be vertically moved up and down, and an elevating mechanism that is interposed between the vehicle body and the vertically movable platform and can be vertically expanded and contracted. , the lifting mechanism consists of three sets of hydraulic telescopic mechanism, combining the lifting mechanism middle of the three sets of hydraulic telescopic mechanism rotatably connected to such a X-shaped, each of the pair of hydraulic telescopic mechanism An elongated cylinder body,
It consists of a pair of rods that can appear in parallel in opposite directions from both ends of each cylinder, and are located on both left and right sides.
Each <br/> one rod of each cylinder body is connected to one of the vehicle body in the two sets of hydraulic telescopic mechanism, located on the left and right sides
It of each cylinder body in the two sets of hydraulic telescopic mechanism
Re the other rod is connected to the other lifting platform, position the left and right sides
One set of hydraulic pressure located at the center of the two sets of hydraulic expansion and contraction mechanism
Two sets of hydraulic expansion / contraction mechanism located on the left and right sides by connecting one rod of the cylinder body in the expansion / contraction mechanism to the other of the vehicle body.
An aerial work vehicle characterized in that the other rod of the cylinder body in the pair of hydraulic expansion / contraction mechanisms located in the center of the vehicle is connected to one of the vehicle bodies. 10. The aerial work vehicle according to claim 9, wherein the cylinders of the respective hydraulic expansion / contraction mechanisms are arranged vertically. 11. The aerial work vehicle according to claim 9, wherein the cylinders of the respective hydraulic expansion / contraction mechanisms are arranged on the left and right sides. 12. A pair of deep holes opened at both ends are bored in parallel in each cylinder body. Each deep hole accommodates a piston that slides airtightly, and each rod inserted from each opening is respectively inserted. The aerial work vehicle according to claim 9, wherein the aerial work vehicle is connected to a piston. 13. A deep hole of each cylinder body is formed to have a large diameter and a small diameter, and the tip of a rod inserted into the deep hole of the cylinder body on both sides is connected to one side of the vehicle body. Connect the tip of the rod inserted into the small deep hole to the other side of the elevator, connect the tip of the rod inserted into the small deep hole of the central cylinder body to the other side of the car body, and The aerial work vehicle according to claim 9, 10, or 11, wherein a tip of a rod inserted into a deep hole of a diameter is connected to one of the lifts. 14. The sum of the cross-sectional areas obtained by subtracting the cross-sectional area of the outer diameter of the rod inserted into the deep hole from the cross-sectional area of the discharge side of the large-diameter deep holes of the cylinder bodies on both sides, and the thin cross-sectional area of the central cylinder body. The cross-sectional area of the pressure side of the deep hole of the diameter is almost the same, and the discharge side of the thick deep hole of the cylinder body on both sides and the pressure side of the thin deep hole of the central cylinder body are connected. The aerial work vehicle according to claim 13.