JPS582197A - Initial push-up mechanism for lifting gear - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lifting device used for lifting workers or materials and lowering unnecessary parts for work at high places, and in particular, the invention relates to a lifting device used for lifting workers or materials and lowering unnecessary parts for work at high places. The present invention relates to an initial push-up mechanism for a lifting device that allows the initial push-up to be performed when slightly lifting the platform and allows the initial operation to be performed smoothly.

For assembly, painting, and repair in high places such as highway corridors and building construction, a lifting device is used to raise and lower a lifting platform, and workers and materials are placed on the lifting platform and lifted or lowered. In this conventional lifting device, a pair of arms are pivoted at the center to make one set, and a pantograph-like extension mechanism is used in which multiple sets of arms are connected in the upper main direction. In order to increase the height, it was necessary to increase the length of each arm or increase the number of connected arms. For this reason, if the height of the lift is increased, the height of the lifting device will be higher when the telescoping mechanism is folded, making it difficult for workers to get on and off the platform.
The work of loading and unloading materials was cumbersome. For this reason, a UNI structure has been devised in which a plurality of booms are telescopically inserted into the inside of the arm so that one arm can extend in its length direction. However, with this configuration, the lifting mechanism cannot be folded! However, when the lifting platform was at the lowest radius position, the center of rotation of the boom and the center of the rotating shafts at both ends of the boom were aligned in a straight line, and the boom could not be extended from that state.

In view of the above-mentioned drawbacks, the present invention provides an initial push-up mechanism for a lifting device that can lift the center of the middle boom at the beginning of the operation of lifting the lifting platform, thereby facilitating the extension of the boom. .

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

Reference numeral 1 in the figure is a truck body.A front wheel 2 and a rear wheel 3 are pivotally supported on the front, rear, left and right sides of the vehicle body 1, respectively.A driver's cab 4 is provided above the front wheel 2.Furthermore, the vehicle body 1 Outriggers 5 are fixed to the left and right sides of the center and rear end, respectively. A kick mechanism 9 is fixed to the upper surface of the vehicle body 1 and to the center of the vehicle body 1. The lifting mechanism 6 consists of four-phase telescopic booms, and each set of telescopic booms is connected to a middle boom 1.
0゜Lower da boom 11. It consists of an upper pool 12.

The center of each middle boom 10 is connected by a connecting shaft 13 so as to be rotatable in an X-shape, and connecting pieces 14 and 15 are fixed to the ends of the lower boom '11 and the upper boom 12, respectively. , the connecting piece 14 is rotatably connected to a defining piece 16 fixed on the vehicle body 1 by a pin, and the connecting piece 1
5 is rotatably connected to a fixed piece 17 fixed to the lower surface of the lifting table 7 by a pin. The intervals between the fixed pieces 16- and the fixed pieces 11 are the same, and the vehicle body 1 and the elevator platform 7 become parallel to each other as the telescopic boom extends in an X-shape. Further, the kick mechanism 9 is located between the two rotating pieces 16 on the vehicle body 1, and this kick mechanism 9 is composed of a hydraulic cylinder 18 that expands and contracts in the vertical direction. A push-up body 19 is fixedly attached to the upper end of the boom 10, which abuts on the lower center surface of the middle boom 10.

Next, FIGS. 4 and 5 show the internal structure of the above-mentioned telescopic boom, that is, the middle boom 10.
It has a structure in which a thin-walled steel plate is bent and the cross section is hollow in the length direction, and a partition plate 20 is fixed to the center in the length direction to divide the interior into two parts. be.

A lower boom 11 and an upper boom 12 are inserted into each chamber divided by a partition plate 20 in the middle boom 10 in an alternating manner of tf'', and the lower boom 11 and the upper boom 12 are attached to the outer periphery of each end. is holder 21.2
The holders 21.22 each hold guide bodies 23.24 that contact the inner wall of the middle boom 10, and the lower and upper booms 11.12 are attached to the guide bodies 23.24. ' 24 to slide inside the middle boom 10.

A hydraulic cylinder redder 25 is housed inside the lower boom 11 along its length, and the base of the hydraulic cylinder 25 is connected to the lower boom 11 by a pin 626. A sprocket wheel 29 is rotatably supported inside the sprocket wheel 29 by a support shaft 30, and both ends of a chain 31 wound around the sprocket wheel 29 are connected to the ends of the lower boom 11 and the upper boom 12, respectively. and sit down.

Next, the operation of this embodiment will be explained.

First, operate the engine (not shown) attached to the vehicle body 1,
This engine drives a hydraulic mechanism to generate oil pressure. This oil pressure is applied to the hydraulic cylinder 18 and each middle boom 10.
It is supplied to the hydraulic cylinder 25 housed in the. For this reason,
The hydraulic cylinder 25 attempts to extend in its length direction and acts to pull out the lower boom 11 from the middle boom 10, but when the telescopic booms are at rest as shown in FIG. 1, each telescopic boom is positioned in a straight line. , no component force is generated in the direction of rotation in an X-shape around the connecting shaft 13, and the lifting platform 7 does not rise. However, since hydraulic pressure is also supplied to the hydraulic cylinder 18, the hydraulic cylinder 18 expands, and the push-up rest 19 contacts the center of the middle boom 10, causing the middle boom 10 to
It acts to push up llf! As shown in Figure 6, lift each middle boom 10 so that it forms a slight X-shape around the connecting shaft 13. When the kick mechanism 9 changes the telescopic boom from its straight state to a slightly crossed state,
In the extension of the hydraulic cylinder 1B and each hydraulic fern 25,
The cylinder rond 27 protrudes from the hydraulic cylinder 25 and widens the distance between the pins 26 and 28, thereby moving the lower boom 11 into the middle boom,
- perform the operation of pulling out from inside the system 10; As the lower boom 11 slides within the middle boom 10, the chain 31 is pulled, and the chain 31 pulls the upper boom 12 while rotating the sprocket 29, and the upper boom 12 is also slid within the middle boom 10. It will be projected from the middle boom 10. From this, lower boom 11.
The upper booms 12 each slide in the opposite direction from the middle boom 10, and the amount of movement is the same, so that they extend by the same amount of protrusion from both ends of the middle boom 10. From this, the interval between each piece 14.15 is expanded by the action of the hydraulic cylinder 25, and the middle boom 10 is connected to the connecting shaft 13.
It rotates in an X-shape around , and lifts the lifting platform 7 higher.

The state shown in FIG. 2 is the state in which the elevating mechanism 6 is fully extended, and the lower boom 11. Since the upper booms 12 each extend to their respective length limits, the total length of the middle, lower, and upper booms 10, 11, and 12 when fully extended is about three times the length of the middle boom 10 alone. Therefore, the lifting platform 7 is lifted up and down by a set of lifting booms arranged in an X-shape in the vertical direction.

Conversely, each hydraulic cylinder 2 is used to lower the elevator platform 7.
By reducing the hydraulic pressure in 5, the lower boom 11 and the upper boom 12 are gradually pushed into the middle boom 10, contrary to the above, the interval between the stg pieces 14 and 15 is narrowed, and the middle boom 10 is connected. The lifting platform 7 is lowered by rotating around the shaft 13. During the descent of the lifting platform 7, as shown in FIG. 6, the push-up rest 19 of the kick mechanism 9 comes into contact with the center of the middle boom 10, and then the hydraulic cylinder 18 is contracted and further raised and lowered. Platform 7 descends. Then, when the lifting platform 7 descends to the lowest position, each telescopic boom is in a straight line, and the lifting platform 7 is at the lowest height position as shown in FIG.

Since the present invention is configured as described above, in a lifting device in which the boom itself extends and contracts to move the lifting platform up and down, it is possible to lift the middle boom at the beginning of the operation and smooth the operation of the expanding and contracting boom.

[Brief explanation of the drawing]

Fig. 1 is a side view of the lifting platform shown in an embodiment of the present invention when it is lowered; Fig. 2 is a side view of the lifting platform shown above when it is at its maximum elevation; Fig. 3 is a rear view of the same; FIG. 4 is a side sectional view of the telescopic boom of the elevating mechanism, FIG. 5 is a sectional view of the same, and FIG. 6 is a side view showing the middle of the operation. 1... Vehicle body, 1... Lifting platform, 9... Kick mechanism,
10... Middle boom, 11... Lower boom, -12
...Upper boom. Patent applicant Mitsuhiro Kishi Patent attorney Nobuo Kobashi Patent attorney Susumu Murai

Claims (1)

[Claims] A pair of internal hollow middle booms are placed slightly in the center of each
The upper and lower booms, which extend and retract at their respective ends, are slidably connected within each middle boom, and each end of the lower boom is attached to a shaft at a distance from the base. In a lifting device that moves the platform up and down by extending and contracting the upper and lower booms from the middle boom, each end of the upper boom is pivoted at intervals on the platform, and the middle boom is attached to the top of the base. A lifting device characterized in that a kicking mechanism is provided so as to be located slightly in the center of the lifting device, the direction of expansion and contraction of the kicking mechanism is aligned with the vertical direction, and the kicking mechanism lifts a slightly center portion of the suspended boom at the beginning of the first stage of the lifting device. initial push-up mechanism.