AU666697B2

AU666697B2 - Improvements relating to retractable covers for open top containers

Info

Publication number: AU666697B2
Application number: AU32181/93A
Authority: AU
Inventors: Bernd Ostermeyer
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-01-31
Filing date: 1993-02-02
Publication date: 1996-02-22
Anticipated expiration: 2013-02-02
Also published as: AU3218193A

Description

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AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT if t S St tt S. St S S

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Application Number: Lodged: Invention Title: IMPROVEMENTS RELATING TO RETRACTABLE COVERS FOR OPEN TOP CONTAINERS St S-S S S t S t if (if if S~tt 55 5 S Sc St 55

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Stt$ The following statement is a fuildescription of this inventionincluding the best method of performing it known to ME

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1 IMPROVEMENTS RELATING TO RETRACTABLE COVERS FOR OPEN TOP CONTAINERS This invention relates to a cover for an open top container which maybe moved selectively between respective positions covering and exposing the open top. The invention is particularly applicable to a cover for open top mobile containers such as incorporated in road and rail vehicles and frequently used for transporting particular materials.

In the transport of materials in open top containers, it is frequently necessary to cover the open top to prevent loss of material in transit, which has adverse economic and environmental results and/or to protect the materials from damage by exposure to atmospheric conditions, such as rain or sunlight.

Currently, conventional tarpaulins are used for this purpose which are manually installed and removed as required. This involves substantial physical exertion 6. by the operator and is also a time consuming operation, which is particularly .i15 relevant in relatively short haul operations where turn-around times must be kept to a minimum.

It is therefore the object of the present invention to provide a retractable cover for open top containers that is effective in operation, can be effectively and rapidly transposed between the operational and inoperative positions and does not interfere with the loading and unloading of the container.

With this object in view, there is provided according to the present invention a retractable cover for an open top container comprising a sheet of flexible substantially non-stretchable material, said sheet being attached along Cot one marginal edge portion thereof to a roller mounted for rotation about an axis parallel to two opposite side edges of the container, whereby the sheet is wrapped about and issued from the roller in response to rotation of the roller in respective opposite directions to cover and uncover the open top, motor means selectively operable to rotate said roller in either direction, and means to maintain said sheet in a tensioned state as it is wrapped about and issued from said roller.

Preferably, one marginal edge portion of the sheet is anchored along one side of the contain-r and the opposite marginal edge portion of the sheet is 2 moved across the open top of the container to or from the opposite side of the container in response to the rotation of the roller in the respective directions.

Conveniently the roller is mounted to move in response to the wrapping or issuing of the sheet by the roller, and the tension means is operable to effect the movement of the roller as the sheet issues therefrom.

More specifically, there is provided a retractable cover for an open top container comprising a sheet of flexible substantially non-stretchable material, said sheet being attached along one marginal edge portion thereof to said container along one side thereof, a roller mounted for rotation about an axis parallel to said attached one marginal edge portion of the sheet, the opposite marginal edge portion of the sheet being attached to said roller so that the sheet is wrapped about and issued from said roller by rotation thereof in respective f opposite directions, motor means selectively operable to rotate said roller in either direction, and means to displace the roller from said one side of the container to the opposite side as the sheet is issued to thereby cover the open top of the container and vice-versa.

Conveniently the roller is mounted at each end on a respective arm, each arm being mounted for pivotal movement about a common axis relative to the container. Each arm is resiliently urged in a direction relative to the container to maintain the sheet in a taut state at all positions of the roller within the extent of movement of the arms relative to the container.

The invention will be further understood from the following description of one practical arrangement of the retractable cover as depicted in the accompanying drawings.

In the drawings, Figure 1 is a perspective view of one end of a truck mounted container incorporating a retractable cover.

The general construction of the container body and the mounting thereof on the vehicle chassis for tilting movement in a sideways direction is basically the same as that described in International Patent Application No.

WO91/00195 and the disclosure therein is hereby incorporated in this specification by reference.

The container body 1 is supported on the vehicle chassis 2 hy rigid 3 arm 4 and hydraulic cylinder 5, each of which are pivotally connected at the lower ends to the vehicle frame 2 with the arm rigidly connected to the upper boundary frame 3 of the container body 1 and cylinder 5 pivotally connected to the upper boundary frame It is to be understood the same configuration of arm 4 and hydraulic cylinder 5 is located at the opposite end of the container 1 and connected to vehicle frame 2 and the perimeter frame 3 of the container in the same manner. The container may be tilted to the left as seen in Figure 1 to discharge the contents thereof by the extension of the cylinders 5. Further, information in regard to the construction of the container and the tilting mechanism is to be found in the above referred to International Patent Application.

The following description, is in respect of the mechanism at the end of the container shown in Figure 1, however, it is to be understood that an identical construction is located at the opposite end of the container.

The control arm 10 is pivotally mounted at the lower end thereof to the S* perimeter frame 3 substantially centrally of the width of the container as indicated generally at 11. Rotatably supported at the upper end of the arm 10 is the roller 12 which extends the full length of the container and is similarly supported at the opposite end thereof. The roller 12 is drive coupled tc an hydraulic motor 13 mounted on the arm 10 and if desired, a further motor of similar type may be mounted at the opposite end of the roller 12. The lower end 14 of the arm 10 extends below the pivot 11 and is connected to one end of the of the bell crank 15 is connected to the rod of the hydraulic cylinder 18 mounted on the bracket 17 secured to the perimeter frame 3.

The cover sheet 20, which is conveniently made of conventional material as used in tarpaulins, is of a flexible but substantially non-stretchable material and is anchored by an appropriate cover strip and fastenings to the wall of the container along the side 21 of the container which is raised during the dumping of the contents of the container and as indicated generally at 22. The other end of the sheet is attached to the roller 12 so that, as the roller is rotated by the hydraulic motor 13, the sheet 20 will be wrapped about the roller 12 when I i~ 4 rotated in one direction and will be issued off the roller when rotated in the opposite direction. As seen in accompanying drawing, the sheet 20 is in a mid position between covering the open top of the container 1 and being retracted to fully expose the open top.

As the roller 12 is rotated in a clockwise direction as seen in the drawing, the sheet 20 will be wrapped about the roller, thus causing the arms to angularly move about the pivot 11 in a clockwise direction to further expose the open top of the container. At the same time, the resilient member 16 will be stretched and hence further tensioned by the clockwise movement of the arm In the fully retracted position, the arm 10 will be substantially in a horizontal or below horizontal position, projecting towards the right as seen in the drawing, so that the roller and the cover sheets 20 are below the level of the top of the boundary frame 3 of the container.

When in this position, the cover sheet is completely clear of the open *-15 top and thus the contents of the container can be discharged by the side tipping Sof the container as the result of operation of the hydraulic cylinder 5 in the known manner.

After the contents of container has been discharged, and the container returned to its normal transport position as shown in the Figure 1, the hydraulic motor 13 is activated to rotate the roller 12 in the anticlockwise direction whereby the cover sheet is payed out or issued from the roller 12, thus allowing the arms 10 to pivot in an anticlockwise direction under the influence of the tension in the resilient member 16, theretv maintaining the cover sheet taut as it is layed out over of the top of the open container. As the roller 12 passes about S 25 the left hand edge of the container and continues to pay out the sheet 20, the tension member will continue to move the arm 10, anticlockwise and downward so the sheet 20, is held firmly against the edge of the container.

Preferably, the length of the cover sheet 20 is sufficient to permit the arms 10 to be moved into a downwardly inclined position with respect to their pivot 14 so that the roller 12 and the cover material thereon will be located inwardly with respect to the boundary frame 3 of the container. This constructional feature has the advantage of maintaining the cover sheet in a taut condition by partially wrapping it about the boundary frame on the left hand side of the container and also brings the roller to a position inwardly of the edge of the boundary frame so that it is within the legal width limit of the vehicle as layed down by the various road authorities. Also, a brake can be provided on the roller so that when actuated, it will lock the roller to hold the sheet in position.

Upon the release of the brake and reversal of the motor 13, the procedure is reversed and the top of the container exposed.

It is to be understood that air or electrically operated components may be substituted for any or all of the hydraulic operated components referred to herein.

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Claims

1. A retractable cover for an open top container comprising a sheet of flexible substantially non-stretchable material, said sheet being attached along one marginal edge portion thereof to a roller mounted for rotation about an axis parallel to two opposite side edges of the container, whereby the sheet is wrapped about and issued from the roller in response to rotation of the roller in respective opposite directions to cover and uncover the open top, motor means selectively operable to rotate said roller in either direction, and tension means to maintain said sheet in a tensioned state as it is wrapped about and issued from said roller in response to operation of the motor means.

2. A retractable cover as claimed in claim 1 wherein one marginal edge portion of the sheet is anchored along one side of the container and the opposite marginal edge portion of the sheet is moved across the open top of the S container to or from the opposite side of the container in response to the rotation by the motor means of the roller in the respective directions. C-Crr C S'CC

3. A retractable cover as claimed in claim 1 or 2 wherein said roller is mounted to move relative to the container in response to the wrapping or issuing of the sheet by the rotation of the roller, and the tension means is operable to i effect the movement of the roller to tension the sheet as it issues from the roller. S

4. A retractable cover as claimed in any one of claims 1 to 3 wherein the CCc motor means is mounted to move with the roller relative to the container as the sheet issues from or is wrapped on the roller.

C C A retractable cover as claimed in any one of the preceding claims wherein the roller is mounted at each end on a respective arm, each arm being mounted for pivotal movement about a common axis relative to the container, each arm being,,f@i rgd in a direction relative to the container to Smaintain the sheet in a taut state at all positions of the roller within the extent of 7 movement of the arms relative to the container.

6. A retractable cover as claimed in claim 5 wherein the length of said sheet is sufficient to permit said respective arm to be moved into a downwardly Cen-orvm6 aCtS inclined position with respect to said,-i4twhen the sheet is in the retracted position and/or extended position.

7. A retractable cover as claimed in claim 5 or 6, wherein said resilient means is arranged so the tension thereof is increased as the sheet is moved toward the retracted position.

8. A retractable cover for an open top container comprising a sheet of flexible substantially non-stretchable material, said sheet being attached along one marginal edge portion thereof to said container along one side thereof, a roller mounted for rotation about an axis parallel to said attached one marginal C edge portion of the sheet, the opposite marginal edge portion of the sheet being r attached to said roller so that the sheet is wrapped about and issued from said roller by rotation thereof in respective opposite directions, motor means selectively operable to rotate said roller in either direction, means to displace the roller from said one side of the container to the opposite side as the sheet is issued to thereby cover the open top of the container and vice-versa, tension means arranged to urge the sheet to move in one direction and to increase in tension as the sheet moves in the other direction. !DATED this 10th day of November, 1995. BERND OSTERMEYER WATERMARK PATENT TRADEMARK ATTORNEYS 4TH FLOOR, "DURACK CENTRE" 263 ADELAIDE TERRACE PERTH W.A. 6000 AUSTRALIA ABSTRACT A retractable cover for an open top container comprising a sheet of flexible substantially non-stretchable material, said sheet being attached along one marginal edge portion thereof to a roller mounted for rotation about an axis parallel to two opposite side edges of the container, whereby the sheet is wrapped about and issued from the roller in response to rotation of the roller in respective opposite directions to cover and uncover the open top, motor means selectively operable to rotate said roller in either direction, and tension means to maintain said sheet in a tensioned state as it is wrapped about and issued from said roller. I 4 .I (rf Ce Ce St t 'I~