JPH07187598A - Container spreader - Google Patents

Abstract

PURPOSE:To provide a container spreader, by which the work speed can be increased and positioning can be facilitated so as to have good work efficiency as the whole, and which is small-sized and low-priced. CONSTITUTION:A container spreader comprises a spreader main body 21 mounted on a front mast in such a manner as to freely elevate, a rail holder 22 installed on the spreader main body, a pair of horizontal rails 23a, 23b which are supported on the rail holder and elongated and contracted sideways, and a pair of vertical supports 25a, 25b. An expansion cylinder 29 for driving the vertical support is interposed between one vertical support and the spreader main body, and the rail holder 22 is provided with a circuit chain 33. Push-pull rods 35a, 35b are respectively interposed between the circuit chain and the forward end of the horizontal rail.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container spreader, and more particularly to a structure of a container spreader suitable for attachment to a cargo handling vehicle such as a forklift.

[0002]

2. Description of the Related Art A container is often used for the efficiency of freight transportation. A conceptual structure of a conventional typical container spreader 1 for handling this container will be described with reference to FIG. A square tube-shaped rail holder 4 is fixed to the front surface of the spreader body 3 attached to the mast (not shown), and from the rail holder 4,
Telescopic rails 5a and 5b extend in the left-right horizontal direction.
And the pillar 2 connected to the telescopic rails 5a and 5b
A twist lock pin 7 is provided at the tip of each of a and 2b.
Is provided, which is inserted into a grip hole of a container having a standardized shape and size to grip the container. Hydraulic expansion and contraction cylinders 9a and 9b are respectively interposed between the spreader body 3 and the respective tip end parts of the expansion and contraction rails 5a and 5b, and the hydraulic expansion and contraction cylinders 9a and 9b and hydraulic pumps provided at appropriate positions on the forklift. A hydraulic pipe is provided between the hydraulic pipe 8 and the pipe 8.

When a forklift equipped with such a container spreader 1 travels under an empty load, the pair of telescopic rails 5a and 5b are drawn into the rail holder 4 on the front surface of the spreader body 3. When gripping the container, the hydraulic pump 8 is driven to discharge the high-pressure discharged oil into the hydraulic telescopic cylinder 9.
When it is fed to a and 9b in two minutes, the pair of telescopic cylinders 9
The hydraulic pump 8 is stopped when a and 9b extend outward synchronously and reach a specified position. Then, the twist lock pin 7 is inserted and locked in the container, the container is lifted, and a predetermined work is performed.

However, in the above-mentioned conventional apparatus, each pair of telescopic rails has one telescopic cylinder, that is, two telescopic cylinders.
Since the two telescopic cylinders 9a and 9b are used, the discharge flow rate from the hydraulic pump 8 is divided into two, and the telescopic rails 5a and 5b
There is a problem that the moving speed of b is slow and work efficiency is poor.

Since the use of two telescopic cylinders causes the above-mentioned problems, a container spreader of a system using a hydraulic motor and a circuit chain has been proposed instead (Japanese Utility Model Laid-Open No. 1-174397). reference). In this method, the discharge oil of the hydraulic pump is supplied to one hydraulic motor, and the sprocket of the circuit chain is rotationally driven. This rotation drive pulls the circuit chain whose end is connected to the boom for suspending the container through the telescopic rail or the telescopic frame, and moves the boom with the twist lock pin in the left-right direction.

Further, in the container spreader described in Japanese Utility Model Laid-Open No. 1-174397, expansion and contraction movement of the telescopic rail is performed by a small piece-shaped stopper provided on the rail holder side and a stopper on the telescopic rail side, respectively. Braking is performed by abutting a small piece-like stopper receiver provided at an opposite position, and as a result, movement of the telescopic rail is forcibly stopped. After that, the lever provided in the driver's seat for controlling the movement of the telescopic rail is operated to completely stop the movement of the telescopic rail. The distance between the twist lock pins at the time of maximum extension and the time of maximum contraction obtained by these stoppers is adapted to match the distance between the hanging holes of two large and small standard containers.

[0007]

As described above, in a container spreader using two telescopic cylinders, work efficiency is low, and in order to prevent this, a large hydraulic pump is required, resulting in cost increase. There was a problem. In addition, in the conventional container spreader that uses a hydraulic motor, there is a restriction that a large hydraulic motor must be installed on the rear part (forklift side) of the container spreader, which reduces the performance of the forklift in terms of weight balance. There was a problem.

Further, since the telescopic rail is telescopically moved at a very high speed in order to speed up the work of loading and unloading the container, a stopper is used for positioning when holding the container in a container spreader using a hydraulic motor. If it is used, a large impact will be caused by the collision between the stopper and its stopper receiver, causing not only wear and damage, but also the impact not only causing failure of various instrumentation parts but also deviation of the stopper setting position. However, there is a problem that the correct position of the telescopic rail cannot be secured quickly, and the position of the twist lock pin and the standard distance between the suspending holes of the container cannot be obtained, which hinders the cargo handling work of the container. there were. Therefore, an object of the present invention is to provide a small-sized and inexpensive container spreader which has a high working speed, easy positioning, good working efficiency as a whole.

[0009]

In order to achieve the above-mentioned object, according to the present invention, a spreader main body which is attached to a front mast so as to be able to move up and down, a rail holder installed on the spreader main body, and the rail. A container spreader having a pair of horizontal rails movably supported by a holder and capable of expanding and contracting laterally, and a pair of vertical columns supported by each of the horizontal rails and having a twist lock pin at a tip thereof is A push-pull rod interposed between a circuit chain arranged in the holder and a tip of the pair of horizontal rails or a lower end of the vertical column is interposed between one of the vertical columns and the rail holder. The horizontal rail is extended and retracted by expanding and contracting the expandable cylinder that is mounted and drives the same vertical column. Preferably, the telescopic cylinder that drives one of the vertical columns is configured to be installed above a rail holder that laterally extends and retracts a pair of horizontal rails.

[0010]

In the above-mentioned structure, when high-pressure oil is supplied to one telescopic cylinder, it is extended, and one vertical column and one horizontal rail connected to the telescopic cylinder are laterally extended. The extension of this one vertical strut is transmitted to the circuit chain via the push-pull rod to move the other push-pull rod and, consequently, another horizontal rail and thus the other vertical strut in a synchronous manner. Let out. If high-pressure oil is supplied from another port of the telescopic cylinder, the associated telescopic cylinder will contract, similar to the above.
Synchronize and contract another horizontal rail. In this way, the pair of horizontal rails, and thus the pair of vertical columns, extend to both sides according to the extension and contraction of one telescopic cylinder,
Degenerate from both sides.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a preferred embodiment of the present invention will be described in detail with reference to the accompanying FIGS. FIG. 1 is a side view of a forklift 10 equipped with a container spreader 20 according to the present invention, FIG. 2 is a front view thereof, and FIG. 3 is a rear view thereof, in which the same reference numerals indicate the same or corresponding parts.

1 to 3, the container spreader 20 is generally attached to an elevating member 12 composed of a lift bracket, a finger bar, etc., which can be moved up and down with respect to the front mast 11 of the forklift 10. The cargo handling work (not shown) is performed. And the container spreader 20 is, as shown in FIG.
The spreader body 21 is formed of a pillar material in a substantially rectangular frame shape so as to be fixed to the front side of the elevating member 12. In addition, the connecting structure of the lifting member 12 to the front mast 11 and the container spreader 2 to the lifting member 12
Since the connection structure of 0 itself is not the gist of the present invention, its detailed description is omitted.

A square tube-shaped rail holder 22 is fixed to the front surface of the spreader main body 21.
A pair of horizontal rails 23a and 23b are provided inside the unit 2 so as to be extendable and contractible in the horizontal direction. The lower ends of the vertical columns 25a and 25b are supported at the tips of the horizontal rails, and the well-known twist lock pins 27a and 27b are attached to the upper ends of the vertical columns. The distance between the twist lock pins 27a and 27b when the horizontal rails 23a and 23b are maximally extended and contracted is set to match the distance between the standard and large grasping holes of the container. 29 is a hydraulic telescopic cylinder arranged horizontally, one end of the piston rod 29a of which is the support 25
The end 29b of the telescopic cylinder 29 is attached to the upper side of the rail holder 22. The inlet port and the outlet port of the telescopic cylinder 29 are connected to a hydraulic pump (not shown) via pipes, hoses, etc. and control valves not shown.

Further, referring to FIG. 3, the spreader body 21
Rear surface of the horizontal rails 23a, 23b (forklift 1
The sprocket (chain wheel) 31a, 31
Two b are axially supported at intervals, and a circuit chain 33 is horizontally wound as a whole between these sprockets. Further, the circuit chain 33 and the end portions of the respective horizontal rails 23a and 23b are provided. Push-pull rods 35a and 35b are arranged between the two.

With the above construction, the forklift 10 is operated to come to a position adjacent to the container to be handled. At this time, the vertical columns 25a and 25b are fully drawn into the horizontal rails of the spreader body 21.
At this time, the distance between the twist lock pins 27a and 27b is equal to the distance between the grasping holes of the small container of the two standard containers of large and small. Then, when the forklift arrives at an appropriate position, a hydraulic pump (not shown) is turned and a control valve is operated to supply the discharged high pressure oil to the telescopic cylinder 29. Thereby, the horizontal rail 23a,
One of 23b extends, and the circuit chain 33 is pulled through one of the push-pull rods 35a and 35b attached thereto.

Therefore, in FIG. 3, the circuit chain 33 rotates counterclockwise and pushes the horizontal rail 23b through the other push-pull rod 35b. That is, as the telescopic cylinder 29 extends, the horizontal rail 2
3a and 23b extend in synchronization. When the twist lock pins 27a and 27b come to predetermined positions, the extension of the telescopic cylinder 29 is stopped, the twist lock pins 27a and 27b are inserted into a container (not shown), and the container is gripped.
Lift, move horizontally, and optionally stack on top of another container already in place. Further, the extension of the telescopic cylinder 29 causes the horizontal rails 23a and 23b to be extended.
When it extends to the full width, the distance between the twist lock pins 27a and 27b determined at that time corresponds to the distance of the gripping hole of the large container of the two standard containers of large and small.

The retractable cylinder 2 is used to retract the vertical columns 25a and 25b and the horizontal rails 23a and 23b.
It is sufficient to supply the discharge oil to another port 9 and shorten the discharge oil. The horizontal rail 23 is synchronized by the operation of the push-pull rods 35a and 35b and the circuit chain 33.
The a and 23b contract and move toward the spreader body side.

Therefore, the container spreader 2 of this embodiment
According to 0, the horizontal rail 23 by the telescopic cylinder 29
By extending and retracting a and 23b, the telescopic cylinder 2
The maximum retracted amount or the maximum extended amount of the horizontal rails 23a and 23b is automatically determined by the expansion / contraction stroke of 9. That is, when the telescopic cylinder 29 is contracted to the maximum and the horizontal rails 23a and 23b are still retracted, the small container of the two standard containers of large and small can be gripped. In addition, the telescopic cylinder 29
When the horizontal rails 23a and 23b are extended to the maximum extent, it is possible to grip a large container of two standard containers of large and small.

As a result, not only is it easy to hold two standard containers, large and small, but also a stopper member conventionally required to forcibly stop the expansion and contraction of the horizontal rails 23a and 23b. Can be omitted. Further, since the extension / contraction cylinder 29 has a limited extension / contraction stroke, it is possible to reduce the impact of the horizontal rails 23a, 23b, which has been a problem in the prior art, when the horizontal rails 23a, 23b are maximally retracted or maximally extended. It is effective in keeping the distance between 27b and the distance between two large and small standard containers or holding holes.

Further, the container spreader 2 of this embodiment
According to No. 0, since the telescopic cylinder 29 is attached to the upper side of the rail holder 22, the distance in the front-rear direction of the forklift 10 is not lost, and the cargo handling performance of the forklift 10 is not deteriorated.

Although the preferred embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and various modifications can be made. For example, in the embodiment, one end of the push-pull rod is attached to the tip of the movable portion of the horizontal rail, but it may be attached to the lower end of the vertical column.

[0022]

According to the present invention, the circuit chain,
When used in combination with a push-pull rod, a single telescopic cylinder can be used to quickly extend and retract the horizontal rail synchronously. And since the telescopic cylinder can be mounted on the top surface of the rail holder instead of on the rear side, the distance between the spreader body and the forklift body is minimized, excellent stability performance is obtained, and a low-cost and compact container spreader is provided. Can be provided.

[Brief description of drawings]

FIG. 1 is an overall side view of a forklift incorporating a container spreader according to an embodiment of the present invention.

FIG. 2 is a front view of the forklift showing the container spreader of FIG. 1 in an extended state on the left side of the figure and in a retracted state on the right side.

FIG. 3 is a rear view of the forklift showing the container spreader of FIG. 1 in the extended state on the left side and the retracted state on the right side in the same manner.

FIG. 4 is a conceptual diagram showing an overall structure of a conventional container spreader.

[Explanation of symbols]

10 ... Forklift, 11 ... Front mast, 20 ...
Container spreader, 21 ... Spreader body, 22 ... Rail holder, 23a, 23b ... Horizontal rail, 25a, 2
5b ... Vertical support, 27a, 27b ... Twist lock pin, 29 ... Telescopic cylinder, 33 ... Circuit chain,
35a, 35b ... Push-pull rods.

Claims (2)

[Claims] 1. A spreader body that is attached to a front mast so as to be able to move up and down, a rail holder that is installed on the spreader body, and a pair of horizontal rails that are movably supported by the rail holder and that can extend and retract laterally. A container spreader supported by each of the horizontal rails and having a pair of vertical stanchions provided with twist lock pins at the ends thereof, a circuit chain disposed in the rail holder, and the ends of the pair of horizontal rails. A push-pull rod interposed between the lower end of the vertical column and the telescopic cylinder that drives the same vertical column interposed between one of the vertical columns and the rail holder. A container spreader configured to extend and retract the horizontal rail. 2. The container spreader according to claim 1, wherein the telescopic cylinder that drives one of the vertical columns is installed above a rail holder that supports a pair of horizontal rails so as to extend and retract laterally.