JPH0338195B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a lifting device capable of lifting personnel and materials to a high place by moving a flat lifting platform up and down from a vehicle body. The present invention relates to an engagement mechanism for an elevating device that can eliminate the difference in level that occurs when a body expands and contracts by moving a spacer, and that can reliably support the load of an elevating platform.

[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 and lifted to a high place or lowered to perform work.

In this conventional lifting device, a pair of arms are pivoted in an X-shape at the center to form one set, and a pandagraph-like extension and contraction mechanism (so-called scissor type) is used in which multiple sets of arms are connected in the vertical direction. was. 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 connected arms. For this reason, when designing a lifting device that can increase the lifting height, it is necessary to use multiple sets of Pandagraphs, which increases the height of the lifting device when the telescoping mechanism is folded, making it difficult for workers to lift and lower the device. The work of getting on and off the platform and loading and unloading materials was cumbersome.

For this reason, an elevating mechanism has been proposed in which multiple booms are telescopically inserted into each other so that one boom can extend in its length direction (for example, Japanese Patent Laid-Open No. 36900/1983, 1978
95100, etc.). In this newly proposed lifting mechanism, two sets of booms are combined in an X-shape so that they can rotate freely at their centers to form a telescoping boom body, and two sets of telescoping boom bodies are arranged in parallel to form four upper and lower booms. The vehicle body and lifting platform were connected by a boom and a lower boom.
Therefore, a large number of telescopic boom bodies must be used, and the number of constituent members becomes extremely large, making manufacturing and assembly complicated and increasing the price.

In addition, the number of sliding parts between each boom is extremely large, and polyamide-based sliding parts are usually attached to these sliding points to smooth the sliding parts. These sliding parts must be replaced and inspected periodically, and when the number of such sliding parts increases, inspection and maintenance become costly and cumbersome.

For this reason, it has been desired to develop a lifting device that reduces the number of telescopic boom bodies used. However, if a lifting device is configured using only one telescopic boom body, each boom of the telescopic boom body combined with a telescopic boom will expand and contract, and it will be difficult to hold one end of the hydraulic cylinder that horizontally supports the lifting platform. I end up not being able to do it anymore. Therefore, the load can be maintained by fixing the upper and outer booms downward from the tip of the upper boom and by interposing a hydraulic cylinder between the upper and outer booms and the lifting platform. However, when the telescopic boom body is extended, a step is created between each boom,
It becomes impossible to support the load from the upper and outer booms. For this reason, there has been a desire for a configuration that can fill the gap between the upper and outer booms and the front boom and support the load even when the telescoping boom body is extended.

[Problem that the invention seeks to solve]

For this reason, an elevating device using a single telescopic boom body has been proposed in which a movable spacer is interposed between the upper and outer booms and the front boom to eliminate the level difference in the telescopic boom body. However, with this configuration, if the spacer interposed between the upper and outer booms and the front boom is not adjusted to an appropriate position, the upper and outer booms will be deformed by the load from the lifting platform. Ta.

The present invention provides an elevating device that provides an engaging means near the upper end of the middle boom, allows the spacer to move together with the middle boom, and releases the coupling near the lower end of the upper and outer booms, thereby supporting the stress applied to the upper and outer booms. This provides an engagement mechanism.

[Means for solving problems]

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, this telescopic boom body includes a lower outer boom having a large outer diameter, a middle boom slidably inserted into the lower outer boom, A front boom that is slidably inserted into the middle boom, and an upper and outer boom that has an inner diameter larger than the outer diameter of the middle boom that moves so as to cover the middle boom and the front boom with its tip fixed to the tip of the front boom. A frame-shaped spacer that can move freely relative to the front boom is inserted into the front boom, and a spacer that slides in contact with the inner circumference of the upper and outer booms is inserted into the upper end of the middle boom. the slider is fixed, the slider is provided with a connecting means that can selectively engage the spacer, and the lower end of the upper and outer boom is provided with an engagement release means that can release the engagement between the slider and the spacer by the connecting means,
This telescopic boom body is provided with a telescoping means that extends and retracts the middle boom and the front boom from the lower outer boom, and a hydraulic cylinder that lowers the telescopic boom body is interposed between the lower outer boom and the vehicle body, and the upper and outer booms and A hydraulic cylinder is interposed between the platforms to hold the platform horizontally, and when the tip of the middle boom is located inside the upper and outer booms, the stress from the platform is supported by the slider. To provide an elevating device characterized in that the stress from the elevating platform is supported by a spacer when the elevating device moves downward from the lower end of the elevating device.

[Effect]

In the present invention, when the telescopic boom body expands and contracts, the slider and spacer are moved in conjunction with each other by the connecting means relative to the front boom, and the spacer can be moved downward. Immediately before the slider leaves the lower end of the upper and outer booms, the engagement between the slider and the spacer is released by the engagement release means, and the spacer remains in that position together with the upper and outer booms. The load from is transmitted to the front boom. Therefore, the upper and outer booms are not deformed by the load, and it is possible to eliminate the difference in level in the telescopic movement of the telescopic boom body.

〔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 part of the upper surface of the vehicle body 1 (on the rear wheel 3 side) at intervals, and between the shaft support pieces 5 is a lower outer boom 6 which is hollow inside and has a rectangular cross section. is inserted, and the shaft support piece 5 and lower outer boom 6
and are rotatably connected by a pin 7. A pair of pins 8 are fixed to the left and right sides of the front part of the vehicle body 1 (front wheel 2 side), which is the upper surface of the vehicle body 1 at a position opposite to the shaft support piece 5. A hydraulic cylinder 9 for suppressing depression is interposed between the outer and lower outer booms 6 and the outer side thereof.

The tip of the lower outer boom 6 has a square opening, and an internal hollow boom 10 having a square cross section is slidably inserted into this opening. A rectangular hollow end boom 11 is slidably inserted therethrough. The tip of the front boom 11 is inserted into a hollow upper and outer boom 12 having a rectangular cross section.
1 and the upper end of the upper and outer boom 12 are connected and fixed. From now on, the outer circumference of boom 11 and upper and outer boom 1
A space with a square cross section is formed between the inner peripheries of the two. The upper boom 12 and lower outer boom 6 are each set to approximately half the length of the vehicle body 1, and the middle boom 10 and front boom 11 are each set to approximately the same length as the vehicle body 1. A telescopic boom body 13 is formed by a lower outer boom 6, a middle boom 10, a front boom 11, and an upper outer boom 12.

Reference numeral 16 denotes a flat lifting platform having almost the same floor area as the vehicle body 1. On the lower surface of this lifting platform 16, a pair of shaft support pieces 14 are provided at a spaced interval on the front part (front wheel 2 side). is fixed. An upper and outer boom 12 is inserted between both shaft support pieces 14, and the shaft support piece 14 and upper and outer boom 12 are rotatably connected by a pin 15. Further, a pair of pins 17 are fixed to each side of the lower surface of the lifting table 16 at a position opposite to the shaft support piece 14.
Hydraulic cylinders 18 for angle correction are interposed between the upper and outer booms 12 and both sides of the upper and outer booms 12, respectively. Furthermore, a handrail 19 is installed around the upper surface of the elevator platform 16.

Next, FIG. 5 is a sectional view showing the inside of the telescopic boom body 13.

Both the lower outer boom 6 and the upper outer boom 12 have a rectangular cross section and a pipe shape, and one end thereof is closed. Inside the lower outer boom 6 and upper outer boom 12, a pipe-shaped middle boom 10 with a rectangular cross section and a slightly smaller outer diameter than the inner diameter of each lower outer boom 6 and upper outer boom 12 can freely slide. It is inserted into. A pipe-shaped tip boom 11 having a rectangular cross section and having an outer diameter slightly smaller than the inner diameter of the middle boom 10 is slidably inserted into the middle boom 10. The front boom 11 and the upper and outer booms 12 are connected and fixed at their upper ends with screws 20.

The interior of the tip boom 11 is hollow over its entire length, and a hydraulic cylinder 21 is housed inside the tip boom 11 so as to be parallel to the length thereof. The base of the hydraulic cylinder 21 is fixed to the lower end of the lower outer boom 6. An adapter 23 is fixed to the cylinder rod 22 of this hydraulic cylinder 21 in a perpendicular direction, and a rod 24 is fixed to the adapter 23 so as to be parallel to the hydraulic cylinder 21. A block 25 is attached to the tip of the rod 24. The lower ends of the middle booms 10 are connected via. Further, a hydraulic cylinder 26 is similarly housed inside the front boom 11, and this hydraulic cylinder 26
The base of the boom 10 is fixed to a block 27 fixed to the lower end of the middle boom 10. A pulley 29 is pivotally supported on the cylinder rod 28 of the hydraulic cylinder 26, and a wire 30 is wound around the pulley 29, with one end connected to the hydraulic cylinder 26 and the other end connected to the lower end of the tip boom 11. There is.

Next, the outer periphery of the front boom 11 and the upper and outer boom 1
A square frame-shaped spacer 31 is inserted into the frame-shaped space formed by 2. The spacer 31 has an inner diameter slightly larger than the outer diameter of the front boom 11 and a slightly smaller outer diameter than the inner diameter of the upper outer boom 12. Therefore, the spacer 31 can freely slide with respect to the front boom 11.

Next, FIGS. 6 and 7 show the interrelationship between the middle boom 10, the tips of the upper and outer booms 12, and the spacer 31.

A slider 32 whose outer circumferential shape is approximately the same as the inner circumferential shape of the upper outer boom 12 is fixed to the outer circumference of the end of the middle boom 10.
The periphery of the upper and outer booms 2 can slide while contacting the inner periphery of the upper and outer booms 12. A concave notch 33 is machined in each of the four centers of the outer periphery of the slider 32, and a claw hole 35 is formed at a position corresponding to the notch 33 on the tip surface of the middle boom 10. There is. An L-shaped engaging claw 36 is inserted into the claw hole 35, and the base of the engaging claw 36 is pivotally supported by a pin 37 so as to be swingable. This pin 3
7 is wound with a spring 38, and the engaging pawl 36 is always biased counterclockwise in FIG. 7 by this spring 38.

This engaging pawl 36 is provided with an actuating part 39 that protrudes upward. It is located protruding from the Further, the distal end of the engaging claw 36 extends linearly toward the distal end of the middle boom 10, and an L-shaped fishing portion 41 is formed at the distal end.

Further, an engagement hole 42 is opened in the side surface (left side in FIG. 7) of the spacer 31, and an engagement pin 43 is fixed in the engagement hole 42. The tip of the hook portion 41 can enter and retract inside the engagement hole 42, and the hook portion 41 is connected to the engagement pin 4.
3 and can be locked.

Further, at the lower end of the upper and outer booms 12 and at the center of each side of the inner periphery, control pins 34 are respectively projected at a height that does not contact the middle boom 10. These notches 33 and the control pins 34 are aligned in opposing positions, so that even if the upper and outer booms 12 move relative to the middle boom 10, the control pins 34 pass through the notches 33 and are not connected to the slider 32. The positions are set so that they will not collide.

Next, the operation of this embodiment will be explained.

Figures 2 and 3 show the state in which the lifting boom body 13 is reduced and the lifting platform 16 is lowered to the lifting position. In this state, a worker is on the lifting platform 16 and materials are placed on it. Then, the lifting platform 16 is raised.

First, the lifting platform 16 is raised by operating the engine in the power box 4 to generate oil pressure and supplying oil pressure to each of the hydraulic cylinders 9, 18, 21, and 26, respectively.

When hydraulic pressure is supplied to the hydraulic cylinders 21 and 26, the cylinder rods 22 and 28 extend respectively to slide and pull out the middle boom 10 from the lower outer boom 6, and also to pull the front boom 11 out from the middle boom 10. Slide and pull out pins 7 and 15.
It acts to widen the space between. Further, when the hydraulic cylinder 9 is extended, the lower outer boom 6 is rotated about the pin 7, and the telescopic boom body 13 is tilted and lifted with respect to the vehicle body 1. At this time, when the extension speed of the telescopic boom body 13 by the hydraulic cylinders 21 and 26 and the tilting speed of the telescopic boom body 13 by the hydraulic cylinder 9 are synchronized, the pin 15 of the upper and outer boom 12 rises perpendicularly to the vehicle body 1. do. Furthermore, the elevating table 16 rotates around the pin 15 due to the extension force of the hydraulic cylinder 18, and acts to enlarge the angle between the upper and outer booms 12 and the elevating table 16. At this time, by synchronizing the extension amounts of the hydraulic cylinders 9 and 18, the lifting platform 16 can be maintained horizontally parallel to the front of the vehicle 1. is formed in a Z shape when viewed from the side.

Once the lifting platform 16 has risen to a predetermined height position, the worker can move the hydraulic cylinders 9, 18, 21, 2
When the operation of the lifting platform 6 is stopped, the lifting platform 16 is held at that height position, and work such as assembly, repair, painting, etc. can be performed at a high place.

When the telescopic boom body 13 is extended by the aforementioned hydraulic cylinders 21 and 26, the hydraulic cylinder 2
6, the middle boom 10 is pulled out from the front boom 11 and the upper and outer booms 12, and the tip of the middle boom 10 moves downward away from the tip of the upper and outer booms 12. At this time, the hook portion 41 of the engagement claw 36 is biased by the spring 38, and since the hook portion 41 is engaged with the engagement pin 43, the spacer 31 follows the movement of the middle boom 10. become. This spacer 31 has an outer diameter and an inner diameter that are slightly smaller than the frame-shaped space formed by the outer circumference of the front boom 11 and the inner circumference of the upper and outer boom 12.
The outer periphery of the front boom 11 can be freely slid. In this movement of expansion and contraction, the hydraulic cylinder 1
The load transmitted from the lifting platform 16 to the upper and outer boom 12 via the slider 32 is supported by the slider 32.
This prevents the upper and outer booms 12 from deforming due to loads.

Further, when the front boom 11 is pulled out from the middle boom 10 and the telescopic boom body 13 is extended, the tip of the middle boom 10 finally reaches near the lower end of the upper and outer booms 12. Then slider 3
The space of the notch 33 formed in the control pin 34
passes, and this control pin 34 comes into contact with the actuating portion 39, causing the engaging pawl 36 to rotate clockwise in FIG. 7 about the pin 37. This engaging claw 3
6, the engagement between the hook portion 41 and the engagement pin 43 is released, and the interlocking movement between the spacer 31 and the slider 32 is released.

If the middle boom 10 still slides, the control pin 3
4 passes the position of the slider 32, and the middle boom 1
0 still moves downward from the lower end of the upper and outer booms 12. At this time, spacer 31 has already been
The lower surface of the control pin 12 is in contact with the lower surface of the control pin 12, and the spacer 31 is held at the lower part of the upper and outer booms 12. Therefore, the spacer 31 is located apart from the slider 32 and between the upper and outer booms 12 and the front boom 11, thereby enriching the space after the middle boom 10 is pulled out. Then, hydraulic cylinder 1
The spacer 31 receives the load of the lifting platform 16 transmitted through the spacer 8, and prevents the space between the upper and outer booms 12 and the front boom 11 from being crushed by the load.

Further, in order to lower the elevating platform 16, the operation is performed in the reverse order to that described above. That is, by reducing each hydraulic cylinder 9, 18, 21, 26, the angle between the vehicle body 1 and the telescopic boom body 13 and the angle between the lifting platform 16 and the telescopic boom body 13 are narrowed, and the middle boom 10 and the front boom are narrowed. 11 to reduce the length of the telescopic boom 13.

As the front boom 11 slides and moves with respect to the middle boom 10, the slider 32 finally reaches the lower end of the upper and outer booms 12, the control pin 34 passes through the notch 33, and the slider 32 moves to the spacer 3.
You will come into contact with 1. At this time, the engaging claw 3
The hook portion 41 of No. 6 enters into the engagement hole 42, and the engagement claw 36 engages the pin 37 against the elastic force of the spring 38.
The hook portion 41 engages with the engagement pin 43. Therefore, the spacer 31 is
2, the spacer 31 slides on the outer periphery of the front boom 11 as the middle boom 10 moves, and the spacer 31 is inserted toward the back of the upper and outer booms 12.

In this way, the lifting platform 16 maintains parallel to the vehicle body 1 and gradually descends, and finally, as shown in FIG. 2, the vehicle body 1, the telescopic boom body 13,
The lifting platform 16 is parallel to the lowermost position.

〔Effect of the invention〕

Since the present invention is configured as described above, it is possible to move up and down a wide area of the lifting platform using only one telescopic boom body for lifting and lowering. Between the upper and outer booms that support the load of the lifting platform and other booms,
Although a step is created when the telescopic boom body is extended and retracted, the step space can be eliminated by the spacer. In addition, it is possible to support a heavy load without the upper and outer booms being deformed by the load.

[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. FIG. 6 is a partial perspective view showing the vicinity of the lower end of the upper and outer booms, and FIG. 7 is a partially enlarged view of the same. 1... Vehicle body, 6... Lower outer boom, 10... Middle boom, 11... Front boom, 12... Upper outer boom,
16... Lifting platform, 31... Spacer, 36...
Engagement claw, 41... hook portion, 43... engagement pin.

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 this lifting device, the telescopic boom body has a lower outer boom with a large outer diameter, and a middle part that is slidably inserted into the lower outer boom. A boom, a front boom that is slidably inserted into the middle boom, and a boom whose inner diameter is larger than the outer diameter of the middle boom whose tip is fixed to the tip of the front boom and moves to cover the middle boom and the front boom. It consists of a large upper and outer boom, and a frame-shaped spacer that can move freely relative to the front boom is inserted into the front boom, and a spacer that is in contact with the inner circumference of the upper and outer boom is inserted into the upper end of the middle boom. The sliding slider is fixed, and the slider is provided with a connecting means that can selectively engage the spacer, and the lower end of the upper and outer boom is provided with an engagement release means that can release the engagement between the slider and the spacer by the connecting means. A telescoping means is provided inside the telescoping boom body to extend and retract the middle boom and the front boom from the lower and outer booms, and a hydraulic cylinder that lowers the telescoping boom body is interposed between the lower and outer booms and the vehicle body. A hydraulic cylinder is interposed between the lifting platforms to hold the lifting platform horizontally, and when the tip of the middle boom is located inside the upper and outer booms, the stress from the lifting platform is supported by the slider. An elevating device characterized by supporting the stress from the elevating platform with a spacer when moving downward from the lower end of the boom.