JPH0233638B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a lifting device that can lift personnel and materials to a high place by moving a lifting platform up and down above a vehicle body, and particularly relates to a lifting device that has a simple configuration and can lift personnel and materials to a high place. This invention relates to an elevating device that can stably hold an elevating platform that has a larger floor area than conventional ones.

[Conventional technology]

Assembly at high places such as highways and building construction,
For painting and repair work, a lifting device that raises and lowers a lifting platform is often used, and workers and materials are placed on this lifting platform to be lifted up or lowered for work.

In this conventional elevating device, a pair of arms are pivoted at the center to form one set of links, and a pantograph-like extension/retraction mechanism (so-called scissor type) in which multiple sets of links are stacked vertically and connected.
was often used. In this mechanism, in order to increase the maximum lifting height of the lifting device, it was necessary to increase the length of each arm or to increase the number of sets of links to be connected. For this reason, when designing a lifting device that can increase the height that can be lifted, it is necessary to use multiple sets of pantographs, and the height of the lifting device with the telescoping mechanism folded becomes high, making it difficult for workers to climb the platform. The work of getting on and off the vehicle and loading and unloading materials was cumbersome.

In order to overcome this drawback, a lifting device has been devised in which a plurality of booms are telescopically inserted into the inside of the arm so that one telescopic boom can extend in its length direction (for example, Patent Application No. 134487 (1982) (Japanese Patent Application No. 1982-36900), Patent Application No. 1982
No. 191065 (Unexamined Japanese Patent Publication No. 58-95100), etc.). In this newly proposed lifting mechanism, two sets of telescoping booms are combined in an X-shape so that they can rotate freely at the center, and two sets of telescoping booms are arranged in parallel to form four upper and lower arms. As a result, the vehicle body and the lifting platform were connected.

This configuration inevitably requires a large number of inserted booms, an extremely large number of component parts, complicates manufacturing and assembly, and increases the price. Additionally, there are extremely many sliding parts between the middle boom and the upper and lower booms, and polyamide-based sliding parts are usually installed at these sliding points, resulting in a large number of parts that must be replaced periodically. However, inspection and maintenance were costly and the work was troublesome.

For this reason, an elevating device has been proposed in which a single telescopic boom body is extended and retracted into a Z-shape when viewed from the side.
242199) etc.). This new lifting device using a single telescoping boom uses a telescoping boom that expands and contracts in multiple stages, so there are steps between each boom.
It is difficult to secure a pivot point for horizontally supporting the lifting platform, and it is also difficult to interpose a horizontal maintenance mechanism between the telescoping boom body and the lifting platform.

[Problem that the invention seeks to solve]

With a single telescopic boom body, each boom slides individually when lifting the platform, and the distance between the booms increases. For this reason, even if you try to interpose a horizontal maintenance mechanism that supports the platform between a boom other than the top boom and the platform, the spacing will change as the platform expands and contracts, making it impossible to keep the platform level at all times. Can not. Additionally, if you try to attach a mechanism to the topmost boom to maintain the level of the platform, the length of the topmost boom to which it can be fixed is extremely limited, and unreasonable force will be applied to the narrow section, causing deformation. Not only that, but it is almost impossible to manufacture.

[Means to solve the problem]

The present invention consists of a movable vehicle body, a flat elevator platform placed above the vehicle body that has approximately the same floor area as the vehicle body, and a plurality of booms with different outer diameters, which are assembled telescopically in the length direction. The base of the boom, which has a large outer diameter, is pivoted to the rear of the top surface of the vehicle body, and the tip of the boom, which has a small outer diameter, is pivoted to the front of the lower surface of the elevator platform. However, in a lifting device configured so that the whole is Z-shaped when viewed from the side, the upper end of a cover body is fixed to the upper end of the small diameter boom at the top stage of this telescopic boom body, and this cover body is The boom is extended downward from the upper end of the vehicle body to cover the telescopic boom body, and the lower end of the cover body is pivotally supported with a roller that rolls in contact with the upper surface of the boom other than the top boom. A hydraulic cylinder that holds down the telescopic boom body is interposed between the upper surface and the boom with a large outer diameter, and a hydraulic cylinder that holds the elevating table horizontally is interposed between the lower surface of the elevating table and the cover body. The present invention provides a lifting device characterized by the following.

[Effect]

When the telescopic boom body is extended, each of the assembled booms is pulled out, and at the same time, the telescopic boom body is depressed, so that the platform is lifted upward. A roller is pivotally supported at the lower end of the cover body constituting the telescopic boom body, and this roller is in contact with the upper surface (back surface) of the booms other than the uppermost boom. Since a hydraulic cylinder for horizontal maintenance is interposed between the cover body and the lifting platform, the stress applied to the lifting platform is applied to the cover body, and then through the rollers to the booms other than the top stage. transmitted to the top of the boom. In this way, even if a load is applied to the cover body from the lifting platform, when the telescopic boom body is extended or contracted, the load is transmitted to the telescopic boom body by the rollers of the cover body, and deformation due to stress can be prevented. .

〔Example〕

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

There are front wheels 2 and rear wheels 3 on the front, rear, left and right sides of the vehicle body 1, respectively.
is pivotally supported so that the vehicle body 1 can move freely, and a power source box 4 containing an engine, a hydraulic pump, etc. is attached to the lower part of the vehicle body 1.

A pair of shaft support pieces 5 are fixed to the rear of the upper surface of the vehicle body 1 at intervals, and a lower boom 6 having a hollow interior with a square cross section is inserted between the shaft support pieces 5. The support piece 5 and the lower boom 6 are rotatably connected by a pin 7. A pair of pins 8 are fixed at intervals on the left and right sides of the front of the vehicle body 1 on the upper surface of the vehicle body 1 at a position opposite to where the shaft support piece 5 is fixed. A hydraulic cylinder 9 is interposed between each pin 8 and the side surface of the lower boom 6 to lower the lower boom 6 vertically about the pin 7.

The lower boom 6 has a hollow shape with a rectangular cross section, and has a rectangular opening at its tip, into which an internal hollow boom 10, which also has a rectangular cross section, can slide freely in the length direction. It has been inserted. Further, the tip of the middle boom 10 has a rectangular opening, and a tip boom 11 having a square cross section and a hollow interior is inserted through this opening so as to be slidable in the length direction thereof.

A cover body 12 having a U-shaped cross section and opening downward is fixed to the top of the tip of the boom 11, and the upper inner surface of the cover body 12 is parallel to the upper surface (back surface) of the lower boom 6. They are spaced apart. Therefore, a gap is formed between the upper surface of the front boom 11 and the inner lower surface of the cover body 12 such that the lower boom 6 and the middle boom 10 can move freely. The entire length of the lower boom 6 is set to be approximately the length of the vehicle body 1, and the middle boom 10 and the front boom 11 are each set to approximately the same length as the vehicle body 1. 6. Telescopic boom body 1 with middle boom 10 and front boom 11
3 is formed.

Here, the reference numeral 16 in the figure is a flat lifting platform having approximately the same floor area as the vehicle body 1, and a pair of shaft support pieces 14 are fixed to the front lower surface of the lifting platform 16 at intervals. A cover body 1 is provided between the two shaft support pieces 14.
The upper end of 2 is inserted, and the shaft support piece 14 and the cover body 12 are rotatably connected by a pin 15. Also, on the lower surface of the lifting platform 16, the shaft support piece 14
A pair of pins 17 are fixed to the rear of the lower surface of the lifting platform 16 at positions opposite to those to which the cover body 12 is fixed. A cylinder 18 is interposed. Furthermore, a handrail 19 is installed around the upper surface of the lifting platform 16 to prevent falling.

5, 6, and 7 show in detail the internal configurations of the telescopic boom body 13 and the cover body 12 described above.

The lower boom 6, the middle boom 10, and the front boom 11
are inserted in the shape of a telespike so that they can freely expand and contract in the length direction. Ahead boom 11
The cover body 12 fixed to the tip (right side in FIG. 5) has an upper side that is approximately 2/3 of the total length of the lower boom 6, and a lower side that is approximately 2/3 of the total length of the lower boom 6. It is set to about 1/3, and the lower surface on the left side of the figure is formed obliquely. A pin hole 21 is provided at the upper part of the lower boom 6 at a position about 1/3 from its left end to connect the hydraulic cylinder 9 for depression suppression. A pin hole 22 for connecting a hydraulic cylinder 18 for angle correction is provided at a position of about 1/2 of the total length.

Further, a shaft support 23 is fixed to the upper surface of the cover body 12 at the left end in the figure (lower position in FIG. 1), and the upper surface of the lower boom 6 ( A roller 24 that rolls in contact with the inner surface of the cover body 12 is pivotally supported on the upper surface of the right end (the upper position in FIG. 1) of the middle boom 10. It is pivoted.

FIG. 6 shows a cross section taken along the line A--A in FIG.

Auxiliary plates 26 are fixed to both sides of the tip of the middle boom 10 (right end in FIG. 5), and pins 2 are attached to the opposing inner sides of the upper part of the auxiliary plates 26.
7 is installed, and the roller 25 is pivotally supported on this pin 27. Further, a support shaft 28 is fixed to the lower part of the auxiliary plate 26, and rollers 29 that come into contact with the outer lower surface of the front boom 11 are rotatably supported on the left and right sides between the auxiliary plate 26, respectively. At the center of the support shaft 28 are a lower boom 6 and a front boom 1.
A pulley 30 is pivotally supported for shifting a chain (not shown) that connects the drive unit 1 with the drive unit 1. Also,
A slider 31 that contacts the outside of the front boom 11 and a slider 32 that contacts the inside of the cover body 12 are fixed to the auxiliary plate 26.

Next, FIG. 7 shows a cross section taken along line B-B in FIG.
A branch piece 33 is fixed to the inside of the shaft support 23 so as to be parallel to the side surface of the shaft support 23, and a pin 34 is installed between the inside of the shaft support 23 and this support piece 33. The roller 24 is pivotally supported.
A slider 35 that contacts the outside of the lower boom 6 is fixed to the side surface of the cover body 12, and a slider 36 that contacts the outer periphery of the middle boom 10 is fixed to the side surface of the lower boom 6.

Next, the operation of this embodiment will be explained.

FIGS. 2 and 3 show the state in which the lifting boom body 13 is reduced and laid down slightly horizontally, and the lifting platform 16 is lowered to the lowest position. In this state, a worker gets on the lifting platform 16 and , materials can be placed on the lifting platform 16. In order to raise the lifting platform 16, the engine in the power source box 4 is operated to generate hydraulic pressure, and each hydraulic cylinder 9, 18
This is performed by supplying hydraulic pressure to a telescopic hydraulic cylinder (not shown) housed in the front boom 11.

When hydraulic pressure is supplied to a hydraulic cylinder (not shown) for expansion and contraction, the middle boom 10 is slid and pulled out from the lower boom 6, and the front boom 11 is slid and pulled out from the middle boom 10, and the pins 7, 1
Increase the distance between 5. Further, by extending the hydraulic cylinder 9, the lower boom 6 is rotated upward about the pin 7, and the telescopic boom body 13 is raised so as to be inclined with respect to the vehicle body 1. When the supply amount of pressure oil is controlled so that the extension speed of the telescopic boom body 13 by the telescopic hydraulic cylinder housed in the front boom 11 and the raising speed of the telescopic boom body 13 by the hydraulic cylinder 9 are synchronized, the cover body Twelve pins 15 rise perpendicularly to the vehicle body 1.

Further, as the hydraulic cylinder 18 expands, the lifting platform 16 is rotated about the pin 15, which acts to enlarge the opening angle between the cover body 12 and the lifting platform 16. Therefore, by synchronizing the extension amounts of the hydraulic cylinders 9 and 18, the platform 16 is always maintained parallel to the vehicle body 1, and the vehicle body 1, telescopic boom 13, and platform 16 are visible from the side. It is formed in a Z-shape. Once the lifting platform 16 has risen to a predetermined height position,
When the worker stops the operation of each hydraulic cylinder 9, 18 and the hydraulic cylinder for extension and retraction in the front boom 11, the lifting platform 16 is held at that height, and work such as assembly, repair, painting, etc. at high places is not possible. It can be performed.

During the telescoping operation of the telescoping boom body 13,
The roller 24 comes into contact with the upper surface of the lower boom 6 and moves while rolling. Also, middle boom 1
The roller 25, which is pivotally supported at 0, comes into contact with the inner peripheral wall of the cover body 12 and moves while rolling during expansion and contraction. Since there is a gap between the cover body 12 and the lower boom 6, middle boom 10, and front boom 11, looseness will occur, and there is a risk of deformation due to the load transmitted from the lifting platform 16. That is, the load of the lifting platform 16 is transmitted to the pin hole 22 via the hydraulic cylinder 18, and the stress applied to the pin hole 22 causes the cover body 12 to be bent downward. but,
As mentioned above, since the roller 24 is rolling in contact with the upper surface of the lower boom 6, the load from the lifting platform 16 is supported by the roller 24 and transmitted to the lower boom 6, so that the cover body 12 is deformed. The lifting platform 16 is held at that height and extended upward together with the front boom 11.

FIG. 8A shows the initial state of expansion, in which the load applied to the pin hole 22 is supported by the roller 24.

As the telescopic boom 13 further extends, the entire length of the lower boom 6 is pulled out from the cover body 12, and the rollers 24 are finally separated from the upper end of the lower boom 6 (see FIG. 8B). At this time, the front boom 11 has been pulled out from the middle boom 10, and the tip of the middle boom 10 is relatively apart from the tip of the front boom 11, and has moved to a position closer to the roller 24 than the pin hole 22. For this reason, the lifting platform 1 added to the pin hole 22
The load from 6 is transferred to the roller 2 through the cover body 12.
5, and the load is supported by the middle boom 10 via the rollers 25. In this way, even if the roller 24 is separated from the lower boom 6, the distance between the inner wall of the cover body 12 and the outer side of the front boom 11 is maintained parallel. When the middle boom 10 further extends and the distance between it and the tip of the front boom 11 widens, the roller 25 approaches the roller 24 even more, and the load on the lifting platform 16 is in the same state as that supported by the roller 24 as described above. Therefore, the stress on the cover body 12 is absorbed, deformation of the cover body 12 is prevented, and parallelism is completely maintained.

FIG. 8C shows a state in which the telescopic boom body 13 is fully extended.

Moreover, when trying to shorten the length of the telescopic boom body 13, the telescopic boom 13 is contracted in the order shown in FIG. This is done by letting In this case, contrary to the above, the rolling of the rollers 25 that support the load of the lifting platform 16 is switched to the rolling of the rollers 24, and the length of the telescopic boom body 13 can be smoothly reduced.

〔Effect of the invention〕

Since the present invention is constructed as described above, the load of the wide platform that is approximately the same size as the vehicle body can be supported by the cover body, and the load applied to the cover body can be transmitted one after another to the telescopic boom body by the rollers. can.

Therefore, even if the angle correction mechanism moves over the step formed by the multiple booms of the telescopic boom body,
The rollers roll to eliminate the difference in level, and deformation due to the load can be prevented even when the lifting platform is raised.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing one embodiment of the present invention;
The figure is a side view showing the lifting platform lowered to the lowest position, Figure 3 is a front view of the same as above, Figure 4 is a side view showing the lifting platform extended to the highest position, and Figure 5 is the telescopic boom. Figure 6 is a cross-sectional view taken along line A-A in Figure 5, Figure 7 is a cross-sectional view taken along line B-B in Figure 5, and Figure 8 shows the operation of the telescopic boom body. FIG. 1... Vehicle body, 6... Lower boom, 10... Middle boom, 11... Front boom, 12... Cover body, 16
... Lifting platform, 24, 25... Roller.

Claims (1)

[Scope of Claims] 1. A movable vehicle body, a flat elevator platform placed above the vehicle body and having approximately the same floor area as the vehicle body, and a plurality of booms with different outer diameters are assembled telescopically in the longitudinal direction. The base of the telescopic boom body, which has a large outer diameter, is pivoted to the rear of the top surface of the vehicle body, and the tip of the boom, which has a small outer diameter, is attached to the front of the lower surface of the lifting platform. In an elevating device that is pivotably supported on the body and configured to have a Z-shape as a whole when viewed from the side, the upper end of a cover body is fixed to the upper end of the small-diameter boom at the top of the telescopic boom body. extends downward from the top end of the top boom to cover the telescopic boom body, and a roller that rolls in contact with the top surface of the boom other than the top boom is pivotally supported at the bottom end of the cover body. A hydraulic cylinder is interposed between the top surface of the vehicle body and the boom with a large outer diameter to hold down the telescopic boom body, and a hydraulic cylinder to hold the platform horizontally is provided between the bottom surface of the platform and the cover body. A lifting device characterized by interposed.