JPH0638869Y2 - Telescopic container spreader - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a telescopic container spreader that is mounted on a forklift and is mainly used for loading and unloading marine containers.

(Prior Art) Generally, a telescopic container spreader has a twist lock 31 for suspending a container at its tip as shown in the schematic view of FIG.
It has a structure in which a pair of left and right telescopic rails 32 equipped with is attached to a corresponding cylindrical rail holder 33 so as to be movable laterally.The rail holder 33 is mounted on a forklift lift via a spreader frame (not shown). It is usually mounted on a bracket. Further, in order to facilitate the expansion and contraction movement of the telescopic rail 32 with respect to the rail holder 33,
As shown in FIG. 8, the rail holder 33 is provided with two guide rollers 34 which rollably contact the upper and lower surfaces of the telescopic rail 32. The guide rollers 34 guide the movement of the telescopic rail 32. However, when the container is suspended, a large load acts on the guide roller 34, which may damage the guide roller 34.

Therefore, as a solution to such a problem, as shown in FIG. 9, the guide rail 34 is provided when the telescopic rail 32 is displaced to the container hanging position on the rail holder 33 (generally at the maximum extension and the minimum contraction). It has been proposed that the guide roller 34 be protected by forming an opening 35 into which the guide rail 34 can enter and directly engaging the telescopic rail 32 and the rail holder 33. An example of the container spreader having such a structure is Japanese Utility Model Publication No. 61-26318.

(Problems to be Solved by the Invention) However, the guide roller escape method using the opening 35 described above has a problem in that the strength of the rail holder 33 is significantly impaired due to the hole penetrating the rail holder 33. Also,
Since the rail holder 33 and the telescopic rail 32 are both formed by bending a steel plate into a tubular shape, it is actually difficult to form the rail holder 33 and the telescopic rail 32 with high flatness. Requires a considerable gap h in consideration of manufacturing error. However, if the gap h between the telescopic rail 32 and the rail holder 33 is large, as shown in FIG.
In particular, when the spreader is lowered onto the top of the container in order to suspend the container C in the most extended state, the spreader's own weight (rail holder, spreader frame, telescopic cylinder, lift bracket, etc. is lifted by a lift chain in a forklift). (Total weight of existing parts)
Thereby, the telescopic rail 32 is inclined. When the inclination is large, the distance H between the lower surface of the rail holder and the upper surface of the container may be narrowed, and the guide roller 34 may come into contact with the upper surface of the container. As a result, the spreader descending operation is performed roughly. At times, there is a problem that the weight of the spreader acts strongly on the container C via the guide roller 34 and the container C is damaged.

Such a container damage problem can be solved by, for example, increasing the height of the rail holder 33, that is, increasing the height H1 of the twist lock holder 36, however, such a solution increases the total height of the forklift. Will cause another problem.

In view of the above problems, an object of the present invention is to provide a telescopic container spreader that is effective in protecting the guide roller and the container.

(Means for Solving the Problems) The present invention is configured as follows to solve the above problems.

In a container spreader in which a pair of left and right telescopic rails equipped with a twist lock for suspending a container at the tip end are attached to a tubular rail holder so as to be movable laterally, A guide roller is attached to the upper surface and the lower surface of the telescopic rail so as to rollably contact and guide the movement of the telescopic rail. Among these guide rollers, at least two guide rollers that receive a load in the suspending direction have an elastic support structure via a spring material.

Further, on the upper surface and the lower surface of the telescopic rail, a groove with which the guide roller of the elastic support structure engages when the telescopic rail is displaced to the hanging position is formed, and the depth of the groove is the telescopic rail and the rail holder. Is formed to be shallower than the gap set on the upper and lower surfaces of and.

(Operation) In the present invention configured as described above, the rail movement at the time of expansion and contraction is guided by the four guide rollers on the left, right, top, and bottom. The variation is absorbed by the vertical movement of the elastically supported guide roller. Also, when suspending the container, the guide roller suppresses the tilt of the telescopic rail when the spreader is lowered onto the top of the container, especially in the extended state, and the distance between the rail holder and the container is kept constant. The interference of the guide roller with the container due to the inclination is eliminated. Moreover, when the container is suspended, the guide roller engages with the groove and then retracts due to the elastic deformation of the spring material, and the suspension load is received by the direct contact between the telescopic rail and the rail holder.

(Embodiment) An embodiment of the present invention will be specifically described below with reference to FIGS. 1 to 7. Lift bracket 2 of forklift 1
On the upper portion of the spreader frame 3 attached to the, two rail holders 4 formed in a rectangular tubular shape are juxtaposed in the front-rear direction. Left and right telescopic rails 5 for each rail holder 4
Are fitted so as to be able to move laterally, and a twist lock 6 for suspending the container is provided at the ends of the telescopic rails 5. The twist lock holder 7 is attached so as to protrude downward from the lower surface of the rail by a predetermined amount.
Then, the left and right telescopic rails 5 are moved by the telescopic cylinders 8, but in general sea containers are classified into 40 feet and 20 feet according to the standard, so the twist lock 6 becomes 40 feet when the telescopic rails 5 are fully extended. Correspondingly, it corresponds to 20 feet at the minimum reduction. Further, the telescopic rail 5 is formed in a rectangular tubular shape similarly to the rail holder 4, and regarding the fitting between the rail holder 4 and the telescopic rail 5, there is a gap h between the facing surfaces in the vertical direction of both. It is formed to allow for manufacturing errors.

Each of the rail holders 4 is provided with a total of four guide rollers 9 in the vertical and horizontal directions for guiding the movement of the telescopic rails 5, and the guide rollers 9 receive a vertical load. Of the four guide rollers 9, the load in the container hanging direction, that is, the telescopic rail 5
The two guide rollers 9 that support the downward load that acts on the two have a resilient support structure by a disc spring, and the other two guide rollers 9 have a fixed structure.

The mounting structure of the guide roller 9 will be described below.
A rectangular ring-shaped mounting body 10 is externally fitted to each of the roller mounting portions of the rail holder 4 (two positions on the left and right sides) and is fixed by welding. Two front and rear roller brackets 11 are mounted on the upper and lower parts of the mounting body 10 with mounting bolts 12, and a guide roller 9 is rotatably mounted between the roller brackets 11 via a roller shaft 13. . A part of the outer circumference of the guide roller 9 enters into the holder through a through hole formed in the mounting body 10 and the rail holder 4 and abuts on the outer surface of the upper or lower part of the telescopic rail 5 in a rollable manner. The degree of contact of the guide roller 9 with the telescopic rail 5 is adjusted by interposing a shim 14 between the mounting body 10 and the roller bracket 11. The roller shaft 13 is prevented from rotating and coming off by the flat surfaces formed on both ends thereof coming into surface contact with the mounting body 10 or the shim 14.

Of the guide rollers 9, the upper and lower two guide rollers 9 on the side receiving the hanging load acting on the telescopic rail 5 are mounted with the heads of the mounting bolts 12 when the roller bracket 11 is assembled to the mounting body 10. Spring support 15
A disc spring 16 is interposed between the roller bracket 11 and the roller bracket 11 to elastically support them. That is, the upper and lower two guide rollers 9 on the side receiving the hanging load have an elastic support structure, and the other two guide rollers 9 have a fixed support structure.

On the other hand, as shown in FIG. 2, the telescopic rail 5 has a portion corresponding to the guide roller 9 of the elastic support structure when the telescopic rail 5 is at the maximum extension and the minimum contraction (in the figure, only two portions for the maximum extension are provided). A relief groove 17 which can be engaged with the guide roller 9 is formed in (shown), and the relief groove 17 has an inclined surface on the rolling side so that the guide roller 9 can be easily moved in and out.
Further, fixed seats 18 are fixed to the upper and lower portions of the inner surface of the rail holder 4 near the guide roller 9 having an elastic support structure. The clearance s between the fixed seat 18 and the outer surface of the telescopic rail 5 is within a range wider than the depth of the escape groove 17, and when the guide roller 9 is engaged with the escape groove 17, It is set as small as possible within a range that is within the allowable elastic displacement.

The present embodiment is configured as described above, and therefore the telescopic rail 5 is used to adjust the distance between the left and right twist locks 6 so as to correspond to the container C to be loaded.
At the time of extension / contraction movement, the extension / contraction rail 5 is guided by the four guide rollers 9 on the left, right, up and down as shown in FIG. In this case, even if the flatness of the rail outer surface, which is the roller rolling surface, is varied (uneven or wavy) due to manufacturing error or the like, this is due to the elastic displacement of the upper and lower two guide rollers 9 elastically supported by the disc spring 16. Since it is absorbed by the telescopic rail 5, the telescopic rail 5 can be smoothly moved.

Then, at the suspending position where the telescopic rail 5 is extended or contracted most, the guide roller 9 having the elastic support structure moves the telescopic rail 5
If the center of gravity of the telescopic rail 5 is located inside the left and right fixed guide rollers 9 at this time, the telescopic rail 5 is held in the same posture as when it is moved, or when it is fully extended. When the center of gravity is between the left and right fixed guide rollers 9 as shown in FIG.
Telescopic rail 5 twist lock 6
Is slightly inclined toward the lower side.

In such a state, the spreader is lowered onto the upper surface of the container C, the twist lock 6 is inserted into the engagement hole of the container, and the twist lock holder 7 is placed on the seat of the engagement hole. At this time, as shown in FIG. 5, the weight of the spreader (the total weight of the members that are hung by the lift chain in the forklift such as the spreader frame 3, the rail holder 4, the telescopic cylinder 8 and the lift bracket) is fixed. Since it is received by the left and right guide rollers 9, the telescopic rail 5 and the rail guide 4 are held in the same posture as when they are moved without tilting. That is, the distance between the rail guide 4 and the upper surface of the container is maintained as set, so that the guide roller 9 or its mounting bolt 12 does not come into contact with and damage the upper surface of the container.

On the other hand, when the twist lock 6 inserted into the engagement hole of the container C is rotated by 90 degrees and locked, and then the container C is lifted by raising the spreader, the telescopic rail 5
Since a large downward load is applied to the guide roller 9, the guide roller 9 is elastically displaced in a state where the guide roller 9 falls into the escape groove 7 of the telescopic rail 5.
That is, the elastic deformation of the disc spring 16 causes the guide roller 9 to retract and the telescopic rail 5 to come into contact with the fixed seat 18 of the rail holder 4. Therefore, a large load acting on the telescopic rail 5 when the container is suspended is directly supported by the rail holder 4 and the load burden on the guide roller 9 having an elastic support structure is reduced, so that the guide roller 9 is prevented from being damaged. .

The guide roller 9 of the fixed support structure described in this embodiment can be changed to an elastic support structure if necessary, and in that case, the spreader is roughly lowered onto the container and the spreader's own weight is applied. This is effective in protecting the roller in the case where the shock acts. Further, in the present embodiment, the case of suspending with two twist locks 6 on the left and right has been described, but it is also possible to apply to a suspending system with four twist locks 6.

(Effect of the Invention) As described in detail above, the present invention is configured to guide the telescopic rail by the four guide rollers of the upper, lower, left and right, and at least the two guide rollers on the side receiving the hanging load. The elastic support structure absorbs variations in the gap between the rail holder and the telescopic rail, allowing the telescopic rail to move smoothly and smoothly, while suppressing the inclination of the telescopic rail when the spreader is lowered onto the container. The problem of container damage due to the guide roller or its mounting bolt can be solved.

Further, in the present invention, since the guide roller having the elastic support structure is dropped into the relief groove formed in the telescopic rail at the suspending position, the load when the container is suspended is directly received by the rail holder. Since the protection groove is provided and the relief groove is used, it is effective in increasing the strength of the telescopic rail as compared with the conventional case of penetrating the opening.

[Brief description of drawings]

1 to 7 show an embodiment of the present invention, FIG. 1 is a cross-sectional view showing the telescopic rail in the middle of movement, FIG. 2 is a cross-sectional view showing the suspended position of the telescopic rail, and FIG. Fig. 2 is a sectional view taken along the line III-III, Fig. 4 is an enlarged view showing the elastic support structure of the guide roller, Fig. 5 is an explanatory view of a state in which the spreader is lowered onto the container, and Fig. 6 is mounting the spreader on a forklift. FIG. 7 is a schematic side view of the same state, and FIG. 7 is a front view of the same. Further, FIGS. 8 to 10 show a conventional example, FIG. 7 is a sectional view showing a moving telescopic rail in the middle, FIG. 8 is a sectional view showing a suspended position of the telescopic rail, and FIG. 10 is a spreader as a container. It is explanatory drawing of the state dropped down. 4 ... Rail holder, 5 ... Telescopic rail, 6 ... Twist lock, 9 ... Guide roller, 11 ... Roller bracket, 16 ... Disc spring, 17 ... Relief groove, 18 ... Fixed seat

Claims (1)

[Scope of utility model registration request] 1. A container spreader in which a pair of left and right telescopic rails having a twist lock for suspending a container at a tip end thereof are attached to a tubular rail holder so as to be movable laterally, and the telescopic rail is provided. At the top, bottom, left and right of the guide rails are attached guide rollers that rollably contact the top and bottom of the telescopic rail and guide the movement of the telescopic rail. Of these guide rollers, at least two guides that receive a load in the hanging direction While forming the roller as an elastic support structure via a spring material, the upper and lower surfaces of the telescopic rail are formed with grooves to be engaged by the guide rollers of the elastic support structure when the telescopic rail is displaced to the suspended position. An extendable container spreader with the groove depth shallower than the clearance set between the top and bottom of the extendable rail and rail holder.