Gantry stacker with two side-by-side spreaders30 June 2010
German firm Noell Mobile Systems is the assignee for a patent where a gantry stacker for transporting and stacking freight containers consists of two chassis beams with steerable wheels, supports, a hoist, an overhead frame, a lifting beam a driver’s cab and engines.
Containers deposited directly side-by-side with no gap between may be gripped, transported and separated or that spaced-apart containers with an alley may be gripped, transported and moved toward each other so that they may be readily transported further, using multispreader systems.
Containers of different heights may be gripped and transported. The lifting height allows for straddling containers standing on the floor with attached and lifted containers.
The solution of the invention provides for a gantry stacker for transporting and stacking freight containers consisting of two chassis beams with steerable wheels, supports, a hoist, an overhead frame, driver’s cab and engines.
There are at least two spreaders that are travelable in a horizontal direction independent of each other and disposed side-by-side on the lifting beam. On this vehicle, two gantries abut on a right and on a left chassis frame, thus, allowing the containers to be transported to be straddled.
A platform mounted in the top region of the gantries offers space for the power train and the hoist. The apparatus is operated by the driver of the vehicle and is capable of grasping containers having several spreaders, preferably two, hanging thereon, and of lifting them with one common rope hoist.
The spreaders are mounted each in one common lifting beam at the front and at the back and are movable sideways independent of each other. With this construction, the two spreaders can be implemented to be flat so that the gantry stacker may be of a small height.
The sideways mobility is configured such that the containers may be moved apart before depositing them so that the alley needed for a conventional straddle carrier can be opened before depositing the containers. Accordingly, parallel standing containers spaced a greater distance apart may be lifted and moved together and be moved from a pre-stacking area to the place where the freight containers are picked up by the spreader system of the gantry crane for loading ship-to-shore cranes.
The suspension of the spreaders in the lifting beams is constructed such that containers of different heights may be lifted with the possible height difference amounting to up to 1ft.
It is advantageous to mount eight steered and individually spring-mounted wheels on the chassis frame; at least four wheels being driven and at least four wheels being braked. Another advantage is to mount one single diesel engine as an energy source. The drive system may be configured both electrically and hydraulically.
The rope hoist is suited for driving both grabbing means, which constitute spreaders. The spreaders are suspended at the front and at the back on one common lifting beam. Due to the gantry construction, two side-by-side containers or four containers of which two are respectively standing one directly behind the other, can be straddled and transported.
The container grabber means, preferably spreaders, are not only independently displaceable in the lifting beams, but are also configured to be horizontally rotatable.
It is advantageous that the suspensions of the container grabber means are configured to be so flexible that different container heights and inaccurate positions are equaled out. Such solutions are known from conventional spreaders on gantry stackers.
Figure 1 shows a gantry stacker for transporting and stacking freight containers consisting of the two chassis frames (2) on which there are disposed springs (6) and four wheels (7) on each frame.
All four wheels are steerable, with two wheels at least being driven and at least two wheels being braked on either side. Supports (8) run from the two chassis frames (2) to gantry (1) on which there are disposed driver’s cab (9) and platform (3).
On the platform, there is disposed a diesel engine or an alternative, independent energy source of the corresponding performance for delivering the electric power needed for driving the wheels.
Two spreaders (5) are disposed on lifting beams (4); said spreaders being movable in a horizontal direction, independent of each other.
The gantry stacker straddles two side-by-side containers (11) deposited by a ship-to-shore crane with tandem spreader system and grabs them with its spreaders (5), lifts them with a common rope hoist (12) and brings them to a site provided for this purpose.
Prior to putting them down, preferably during the travel, the two spreaders travel on the lifting beam so that the containers are spaced a distance apart and form an alley that may be straddled by conventional gantry stackers.
The solution proposed has the advantage that containers deposited directly side-by-side with no gap between may be gripped, transported and separated or that spaced-apart containers with an alley may be gripped, transported and moved toward each other so that they may be readily transported further, using multispreader systems.
While only a few embodiments of the present invention have been shown and described, it is obvious that many changes and modifications may be made thereunto without departing from the spirit and scope of the invention.
About the patent
US Patent number 7,731,041 was awarded to Martin Gredel and Hubert Foltys, of Germany. The assignee is Noell Mobile Systems GmbH. Application number 12/152,018 was filed on May 12, 2008.
As an edited version of the original, this article may omit legally or technically important detail.