JPH0754240Y2 - Aerial work vehicle - Google Patents

Description

[Detailed Description of the Invention] (b) Industrial field of application The present invention has a scissor link mechanism interposed between a workbench and a traveling platform, and the scissor link mechanism is expanded and contracted by a lifting hydraulic cylinder to perform work. It relates to an aerial work vehicle that raises and lowers a platform.

(B) Conventional Technology Conventionally, a technology related to an aerial work vehicle having a scissor link mechanism is known.

The technique is described in JP-A-63-277189.

However, the biggest cause of the backlash of the scissor link mechanism is that the inner scissor link is interposed between the outer scissor links, and the pivot shaft is centered between the inner scissor link and the outer scissor link. Since rotation is performed, there are few things that pass between the inner scissor links, so it can be connected by a connecting reinforcing material, but since the inner scissor links are arranged between the outer scissor links,
It is not possible to firmly connect the outer scissor links, and there is rattling between the inner scissor links and the outer scissor links, and this rattling appears as runout when the workbench is raised. It was.

According to the present invention, the inner scissor link is arranged, only the part to be rotated has a hole opened, and the connecting plate that reinforces only the part that does not interfere with the rotation of the inner scissor link in the other parts is provided with a connecting plate. By connecting them, the outer scissor links are strengthened, and the backlash is reduced even when the scissor link mechanism is extended.

In order to prevent the backlash of the scissor link mechanism from occurring, a technique in which a bar spring is interposed between the outer scissor links is known. For example, it is as in the technique described in JP-A-48-47101.

(C) Problems to be solved by the invention However, in the above-mentioned conventional technique, the outer scissor links are connected and reinforced by a plurality of bar springs arranged in parallel with the pivot shaft. A parallel link state composed of a bar spring and a pivot is completed, and the parallel link may be twisted or bent in the direction of a parallelogram.

In order to eliminate such a problem, the present invention replaces the conventional bar spring and replaces the plate-like connecting plate 3 between the outer scissor links 2 and 5.
Is fixed with bolts.

(D) Means for Solving the Problems The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described.

In the scissor link mechanism that is configured by combining the inner scissor links 1 and 4 and the outer scissor links 2 and 5, a part that avoids the intermediate pivot shaft that pivotally supports the intermediate part of the scissor links between the outer scissor links 2 and 5. On the connecting bracket
A plate-like connecting plate 3 which projects 6,6,6,6 and reinforces the left and right outer scissor links 2,5 between the connecting brackets 6,6,6,6
Is fixed by a bolt, and in the space between the plate-like connecting plate 3, the connecting brackets 6,6,6,6 and the outer scissor links 2,5,
The inner scissors links 1 and 4 pivotally supported to be rotated up and down by an intermediate pivot shaft are passed through.

(E) Embodiment The problems and means for solving the present invention are as described above. Next, the structure of the embodiment shown in the accompanying drawings will be described.

Fig. 1 is a side view of an aerial work vehicle, and Fig. 2 is an inner scissor link 1,4 and an outer scissor link 2,5 of the scissor link mechanism.
Shows a part of the inner scissors links 1 and 4 intersecting with the connecting portion of the intermediate pivot shafts 8 and 8, and the scissors link mechanism is in a front view in a stretched state. FIG. 4 is a side cross-sectional view in a closed state, and FIG. 4 is a front sectional view in a folded state.

In FIG. 1, a scissor link mechanism is interposed between the workbench 11 and the traveling base 12. A caster wheel 31 and a drive steering wheel 32 are provided below the traveling platform 12.

The scissor link mechanism is expanded and contracted by the operation of the lifting cylinder S shown in FIG. 1, and the slide rail 13 on which the supporting roller at the tip of the outer scissor link at the upper end slides is attached to the work table 11.
It is attached to the lower surface of.

Further, a slide rail 14 on which the supporting roller of the scissor link inside the lower end slides is formed on the upper surface of the traveling platform 12.
The sliding rails 13 and 14 enable folding of the scissor link mechanism.

As shown in FIG. 2, since there is no interference between the inner scissor links 1 and 4, it is possible to provide a reinforcing member for connecting the inner scissor links 1 and 4 to each other.
The left and right can be integrated to form a strong structure so that no shake occurs.

However, since the inner scissor links 1 and 4 rotate between the outer scissor links 2 and 5, it is impossible to dispose a reinforcing material such as a large diameter pipe.

In particular, since the inner scissor links 1 and 4 cross at the intermediate portions of the outer scissor links 2 and 5, it is necessary to provide a rotation passage portion for the inner scissor links 1 and 4 in the vicinity thereof.

In the present invention, connecting brackets 6,6,6,6 are provided on the upper and lower parts between the outer scissor links 2,5 so that the middle inner scissor links 1,4 pass through and the upper and lower ends are Leave it as a space.

Then, the plate-like connecting plate 3 for reinforcing in a plow shape is fixed by bolts between the connecting brackets 6, 6, 6, 6. When the connecting brackets 6, 6, 6, 6 and the plate-like connecting plate 3 that reinforces in a plow shape are integrated from the beginning, the inner scissor links 1, 4 are fitted inside and the intermediate pivot shafts 8, 8 are used. It cannot be fixed.

In the embodiment of FIG. 2, the intermediate pivot shafts 8 and 8 are not connected to each other on the left and right, but are divided into two left and right shafts at the center to form two intermediate pivot shafts 8 and 8. Therefore, the plate-like connecting plate 3 connected to the four connecting brackets 6, 6, 6, 6 can be arranged between the intermediate pivot shafts 8, 8.

In FIGS. 3 and 4, the connecting plate brackets 6, 6, 6,
A state in which elastic plates 7, 7 are attached to the upper and lower surfaces of 6 is disclosed.

As shown in Fig. 3 and Fig. 4, when the scissor link mechanism is folded, if it is stored for a long time in that state, rust will occur, and in the folded state, each inner scissor link 1, 4 Since the contact state between the outer scissors link 2 and 5 and the gap generation state do not match, it is not possible to expect a state where all of them evenly contacted, only one point somewhere contacted, all other links in this part In some cases, the single point support portion may be damaged, so the elastic plates 7 and 7 are interposed so that all links can be contact-supported as much as possible.

Figure 5 shows the inner scissor rink 4 and the outer scissor rink 5.
6 is a front cross-sectional view of the pivotal support portion of FIG. 6, and FIG. 6 is an inner scissor link that intersects at the end of the inner scissor links 1 and 4 and the outer scissor links 2 and 5 of the scissor link mechanism and the intermediate pivot shaft 10 portion. FIG. 7 is a front view showing a part of parts 1 and 4 with the scissor link mechanism extended, and FIG. 7 is a view showing another embodiment of the intermediate pivot shaft 10 part.

A reinforcing member is erected between the inner scissor links 1 and 4 to form an integral part, and the inner scissor links 1 and 4 include one intermediate pivot shaft 10 and two end pivots. It is necessary to insert the shafts 15 and 16, and the intermediate pivot shaft 10 and the end pivot shafts 15,1
The position of 6 is the position of the pivot hole of the outer scissor links 2 and 5,
Must match exactly.

In this case, the inner scissors links 1 and 4 become large parts with the reinforcing material attached, and in this large part, the positions of the intermediate pivot shaft 10 and the end pivot shafts 15 and 16 are machined to the core. If it is taken out, a dedicated machine or a large processing jig is required.

Also, after accurately positioning the positions of the intermediate pivot shaft 10 and the end pivot shafts 15 and 16 with the jig, the inner scissor links 1 and 4
There is also a method in which the cores are welded together to obtain an accurate center-to-center distance, but this also causes distortion during welding, and it is difficult to maintain accuracy due to variations.

In this configuration, in order to solve this problem, the fifth
In Figures and 6, the boss 1 is attached to the inner scissor links 1 and 4.
Weld fixed 7,17 to inner scissor links 1 and 4, boss 1
With 7, 7 attached, machine processing is performed by itself to perform centering, and the intermediate pivot shaft 10 and the end pivot shafts 15, 16 are press-fitted to the inner scissor links 1, 4 in order. is there.

Although the connecting plate 9 is not yet fixed at this point, the center pivot shaft 10 and the end pivot shafts 15 and 16 are press-fitted into the inner scissor links 1 and 4 to improve the centering accuracy. After that, the connecting plate 9 is fixed by welding.

After the inner scissor links 1,4 are fitted between the left and right outer scissor links 2,5, a plate-like connecting plate 3 for reinforcing in a plow shape is fixed to the connecting brackets 6,6,6,6. The outer scissor links 2 and 5 are also steady.

In the embodiment of FIG. 7, the intermediate pivot shaft 10 and the end pivot shafts 15 and 16 are connected to the bosses 17 and 17 with the bearing metal interposed therebetween instead of press-fitting the bosses 17 and 17. Inserted in 17, and similarly to the outer scissor links 2, 5 shown in FIG. 2 to FIG. 4, the connecting brackets 6, 6, 6, 6 are also provided between the inner scissor links 1, 4, By fixing the plate-like connecting plate 3 that reinforces in a plow shape, the inner scissor links 1 and 4 are centered and the steadying strength is improved.

In the embodiment shown in FIG. 5, FIG. 6 and FIG. 7, since the intermediate pivot shaft 10 is configured as a long shaft penetrating left and right, the plate-like connecting plate 3 and the intermediate pivot shaft 10 are inside. Scissor link
Since the plates 1 and 4 interfere with each other inside, four plate-like connecting plates 3 are provided between the outer scissor links 2 and 5, and the left and right ends are connected to the connecting brackets 6 and 6 by bolts. .

8 is a sectional view of the lifting cylinder S shown in FIG. 1, FIG. 9 is a sectional view of the orifice seal 25 of the lifting cylinder S, and FIG.
The figure is a sectional view of a conventional lifting cylinder S.

The elevating cylinder S is provided with a cushion mechanism so as to descend at a slow speed immediately before the end of the descent of the scissor link mechanism and absorb the impact at the descending end.

As shown in the prior art of FIG. 10, the cushion sleeve 22 is conventionally provided with a throttle hole 22a,
Since the passage of the pressure oil is throttled to the throttle hole 22a from the time when it is inserted into the bottom hole 33, the discharge amount of the pressure oil from the oil passage 30 is limited to form a cushion mechanism. 20
Is piston rod, 21 is piston, 19 is cylinder, 23,3
0 is a pressure oil passage.

However, in the prior art, the cushion sleeve
Therefore, the accuracy of 22 points, the accuracy of the bottom hole 33, and the accuracy of the position of the piston rod 20 are required at three points.

The present invention is provided with an orifice seal 25 as shown in FIG. 9 so as not to require such accuracy. The orifice seal 25 is provided with a throttle hole 25a,
Only the pressure oil throttled from the throttle hole 25a can be discharged from the oil passage 30.

The orifice seal 25 is fitted in the bottom hole 33, and the direction of the orifice seal 25 is such that the lip faces the direction in which the piston rod 20 is fitted.

(F) Effect of the Invention Since the present invention is configured as described above, it has the following effects.

First, since the outer scissor links 2 and 5 are connected to each other via the plate-shaped connecting plate 3, as in the case where the scissor links are connected to each other by the bar spring in the conventional technique, The parallel link composed of the scissors link, the bar spring, and the pivot is no longer twisted or bent in the parallelogram direction in the parallel link state.

Secondly, the plate-like connecting plate 3 is provided between the scissor links 2 and 5 on the outside.
Since the workbench 11 is maximally raised by the fixed connection with the wobble, it is less likely that the outer scissor links 2 and 5 will be shaken and that the runout will occur.

Third, the outer scissor links 2,5 to the connecting bracket 6,
Since the plates 6, 6 and 6 are projected and the plate-like connecting plate 3 is fixed to the connecting brackets 6, 6, 6 and 6 by bolts, the inner scissor links 1 and 4 and the outer scissor links 2 and 5 are connected. At the time of assembling, since the plate-shaped connecting plate 3 is assembled with the connecting brackets 6, 6, 6, 6 removed, the plate-shaped connecting plate 3 does not interfere with the assembly.

[Brief description of drawings]

Fig. 1 is a side view of an aerial work vehicle, and Fig. 2 is an inner scissor link 1,4 and an outer scissor link 2,5 of the scissor link mechanism.
Shows a part of the inner scissors links 1 and 4 intersecting with the connecting portion of the intermediate pivot shafts 8 and 8, and the scissors link mechanism is in a front view in a stretched state. FIG. 4 is a front sectional view of a folded state, FIG. 4 is a front sectional view of a folded state, FIG. 5 is a front sectional view of a pivotal support portion of the inner scissor link 4 and the outer scissor link 5, and FIG. 6 is an inner scissor link of the scissor link mechanism. Front view of the state in which the scissor link mechanism is extended, showing the connection between the end portions of 1,4 and the outer scissor links 2,5 and a part of the inner scissor links 1,4 that intersect at the intermediate pivot shaft 10 part. FIG. 7 is a drawing showing another embodiment of the intermediate pivot shaft 10 portion, FIG. 8 is a sectional view of the lifting cylinder S shown in FIG. 1, and FIG. 9 is an orifice seal.
FIG. 25 is a sectional view of FIG. 25, and FIG. 10 is a sectional view of a conventional lifting cylinder S. 1,4 …… Inside scissors link 3 …… Coupling plate for reinforcing in a plow shape 2,5 …… Outside scissors link 6 …… Coupling bracket 7 …… Elastic plate 8 …… Intermediate pivot shaft 9 …… Plate-shaped coupling plate 10 …… Intermediate pivot shaft 15,16 …… End pivot shaft

Claims (1)

[Scope of utility model registration request] 1. A scissors link mechanism configured by combining inner scissors links 1,4 and outer scissors links 2,5, wherein an intermediate pivot for pivotally supporting an intermediate portion of the scissors links between the outer scissors links 2,5. In the part where the axis is avoided,
The connecting brackets 6, 6, 6, 6 are projected, and the connecting brackets 6,
A plate-like connecting plate 3 that reinforces the left and right outer scissor links 2,5 is fixed between the 6,6,6 with bolts, and the plate-like connecting plate 3
And that the inner scissors links 1 and 4 pivotally supported to rotate up and down by the intermediate pivot shaft pass through the space between the connecting brackets 6, 6, 6 and 6 and the outer scissors links 2 and 5. A featured aerial work vehicle.