Expandable Cover System

Abstract

This disclosure describes an expandable cover system which includes a work base and a plurality of inverted U-shaped frames which are supported on the base. Each of the frames have adequate sheet means to cover the frames in a waterproof manner. The frames are of different sizes so that they can nest, one inside of the other. The largest frame is fixed to the base at one end thereof, and the others are supported on two lines of rollers which are positioned under the legs of each of the frames so that they can be moved in a line perpendicular to the plane of each of the frames. There are projections on the inside and outside of each of the frames so that they can interact with corresponding projections on the adjacent frames so that when the inner frame is pulled longitudinally it will successively pull with it, the adjacent frame, then the next adjacent frame and so on. Conversely, when the smaller frame is pushed toward the stationary one the intermediate frames will successively be carried by the smallest one, riding on the rollers, until they are all nested inside of the stationary frame. A traversing means, such as a pair of longitudinal screws with nut means attached to the legs of the smallest frame are provided. These are arranged adjacent and parallel to the lines of rollers, so that the inner frame can be moved from the nest position to an extended position, carrying with it each of the intermediate frames until the group is fully extended. There are guide slots on the base so that the frames are guided laterally as they move longitudinally.

Description

BACKGROUND OF THE INVENTION

This invention is in the field of expandable cover means, or expandable canopy means. More particularly, it comprises a mechanical drive system for moving the group of separate frames or canopies from a nested position where the base is substantially completely exposed to the atmosphere, to a position in which each of the canopies are extended to form a complete waterproof cover over the base, or space.

In the prior art there are a number of illustrations of systems whereby rotating segments of a segmental canopy can be moved into a position to completely cover and shield a work area. Some of these operate by rotation of elements, others by translation, somewhat similar to the present invention. However, the present invention has a number of improvements which will be described.

SUMMARY OF THE INVENTION

It is a primary object of this invention to provide a movable frame or canopy system which can be installed on a work platform so that by operation of a single drive means the separate canopies can be extended in abutting relationship to provide a complete waterproof cover over the work area. Conversely, they can be moved into position so they completely nest within one another.

This and other objects are realized and the limitations of the prior art are overcome in this invention by providing the separate canopies in the form of inverted U-shaped frames which stand upon the two legs of the U. There is a longitudinal base under each of the legs which carry two lines of rollers transverse to the plane of the frames, one line of rollers under each leg. The rollers are long enough so that a plurality of frames each successively larger than its neighbor can be supported on the rollers. Each of the rollers can be single, solid, long rollers or a plurality of individual short rollers rotating on a fixed shaft, each short roller supporting one leg of one frame.

One of the frames is the largest and is fixed to the base and the lines of rollers extend along the work floor from the base of the largest frame.

Parallel to the lines of rollers there are two operating means. There may be lead screws or chains, such that through means such as a nut attached to the screw the smallest of the frames can be moved longitudinally along the line of rollers.

Each of the frames has projections on its inside and outside walls which interact with corresponding projections on the inside and outside walls of the adjacent frames so that by driving the smallest frame, it engages the next larger frame to pull it along, which next larger frame engages the successively larger frame to pull it along, and so on. The drive means need only connect with the smallest frame.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects of this invention and a better understanding of the principles and details of the invention will be evident from the following description taken in conjunction with the appended drawings, in which:

FIG. 1 represents an end view of the nested plurality of frames or canopies.

FIG. 2 illustrates a side view of the group of frames in their extended position.

FIG. 3 illustrates a detail of the drive means and the rollers.

FIG. 4 illustrates a detail of the construction of the frames.

FIGS. 5 and 6 illustrate details of the sealing means to prevent rain from entering the space below the canopies when they are fully extended.

FIG. 7 illustrates further detail of the drive means.

FIG. 8 illustrates the detail of the support rollers supporting each of the legs of the plurality of frames.

FIG. 9 illustrates a view of the expanded cover including an overhead support rail for a crane or other means for lifting work when the cover is retracted.

FIG. 10 illustrates a detail of the drive means using a chain in place of the screw.

FIG. 11 is a structural detail of the support frame for the lifting means.

FIG. 12 illustrates schematically the chain system of driving the canopies.

FIG. 13 illustrates a detail of the projections or stops attached to each of the frames.

DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 illustrates a view of the plurality of canopies or frames in their nested position. They comprise a group of inverted U-shaped frames, each of which comprise a substantially horizontal roof portion 12A, 12B, 12C...12N for each of the frames, with correspondingly substantially vertical leg portions 14A, 14B...14N and 16A, 16B...16N. The outer largest frame 12A is supported on and fixed to longitudinal support means, or base, 18A and 18B. Within the support means 18, as will be described in connection with FIG. 8, are a plurality of rollers which support the legs of each of the plurality of frames.

Referring now to FIG. 8, the base 18A is seen to support an axle 36 on which a group of rollers 34B, 34C...34N are freely rotatable. The outer frame 14A is supported directly on the base 18A. The frame 14B has a base portion 30B which is supported on one, 34B of the plurality of rollers, each of which rotates on the shaft 36. Similarly, frame 14C is supported on a base 30C which is supported on roller 34C which rotates freely on the shaft 36, and so on. The base 18A carries a plurality of slots 32B, 32C...32N by means of which the corresponding legs 14B, 14C...14N are guided laterally along the line of rollers. Thus, each of the frames or canopies is free to move perpendicular to its plane, along the lines of rollers, parallel to the motion of each of the others so that they move from a nested position to an extended position simply by moving outwardly along the line of rollers.

Referring to FIG. 13 there is shown in cross section one leg of each of frames 14B and 14C which are parallel to each other and of the same length. Each has a group of projections 40B, 42B, 44B and correspondingly for the leg 14C. While there is clearance for each of the legs to move past the other the projection 40C, for example, interacts with projection 42B so that when leg 14C moves in the direction of the arrow 43 and projection 40C strikes the projection 42B then leg 14B will move with it. Conversely, when leg 14C moves in the other direction it will move freely until the projection 44C strikes the projection 42B and causes the leg 14B to move with the leg 14C. Since each of the canopies or frames are interacted this way by means of the projections, or stops, all that is required is to move the inside frame 14N, and it will, in turn, move each of the others as required to put them in a nested position, or to extend them in overall covered position.

The drive means is illustrated in FIGS. 3, 7 and 8. In one embodiment a longitudinal lead screw 47, with threads 46, is mounted in a horizontal plane parallel to the line of rollers and adjacent the legs 14N, 16N of the inner canopy 12N. A nut 48 is fastened around the lead screw 47 and is attached by means 50 to the bottom inside wall of the leg 14N of the inner frame. Thus by turning the shaft 47 the screw will turn, the nut 48 will move along the screw and carry with it the inner frame 12N. As this continues to move it slides along the line of rollers 34N. It carries with it the adjacent frames by means of the projections 40, 42, 44, and so on, until all of them are moved to one extreme or the other of their positions.

In FIG. 3 is shown schematically a side view of which the relative position of the rollers 34 and the lead screw 46 are shown. The screws 38 are for fastening the support means 18A and 18B to the base platform in a rigid longitudinal parallel relationship.

It is important that the two lead screws, one driving each leg of the inner frame be rotated in synchronism. As shown in FIG. 7 this is accomplished in either of two ways. A pair of bevel gears 52 and 54 are provided to rotate a transverse shaft 56, which has, at its other end, adjacent the second lead screw, a corresponding pair of bevel gears so that by rotating one shaft 47 the second screw shaft will rotate in synchronism and therefore the two legs of the frame 12N will move together. Conversely, it is possible to use a sprocket on the end of the shaft 47 and a chain 60 to tie the two lead screws in synchronism.

In FIG. 12 is shown schematically an alternative method of driving the legs 14N and 16N of the frame 12N. A complete, closed loop of chain is wrapped around sprockets 82 and 85 (which are mounted on separate horizontal shafts similar to 47) with a drive means 86 attached to one of them. There are two pairs of sprockets 83 and 84 (with vertical shafts) so that the longitudinal line of chain 88 which is attached to leg 14N by means 87A will pass around the sprockets 83 and 84 and then will traverse a parallel path 89 back to the sprocket 85. The direction of looping of the chain around the drive sprocket 82 and 85 is such that the two legs 14N, 16N move in the same direction as the crank 86 is turned.

FIG. 10 illustrates a detail similar to a portion of FIG. 8 wherein the chain 70 is looped around the sprocket on shaft 72 and passes through a chain fixture 48' in which the chain is locked. This fixture is supported by arm 50' from the leg 14N so that as the chain moves longitudinally, being locked in the fixture 48' it will move with it the leg 14N, etc.

Referring now to FIG. 5 there is shown the frame 62B in extended relation with respect to 62A. The frame or canopy has two yokes or inverted U frames, one at each end 62B and 66B, for example, with a web or skin 68B which provides a waterproof cover. In addition, there may be crossbracing and intermediate yokes, etc. which are not shown. In the extended position the yoke 66A from the first frame seals the gap between 68A and 68B. This involves a fixture 64B and a corresponding overlapping pair of surfaces 67A and 69B.

FIG. 6 shows the view of the canopies in a nested position. In this position of course there is not a complete sealing of the skin and this would not necessarily be required since the work space, the base, is not covered.

In FIGS. 9 and 11 are shown some details of an overhead rail 74 supported on yokes 76, 78, etc. The yokes 78 slide in bases 18A and 18B. They support cross rails 80 to which the overhead rail 74 which can be used to support a crane or other lifting means. The forward yoke 76 can be attached, for example, to the fixed canopy 12A.

The overhead rail and yoke arrangement is particularly important in that it permits the expandable covers to be stacked one on top of the other when not in use.

The front end of the canopy, or cargo cover, is shown as being open. However, it will be clear that it will be possible to provide a waterproof skin means to be placed across this opening and/or to have a roll type sheet means which can be lowered to cover the opening of the end of the small canopy.

While the use of rollers 34B, 34C..34N are desirable it can be seen that in its simplest embodiment the use of rollers is not required and that the lower ends of the canopies may slide on bases 18A and 18B. When the rollers are not used a material having a low coefficient of friction may be emoloyed between the canopies and bases 18A and 18B, such as a layer of Teflon.

It can be seen that the canopy sections are configured so that there are no planar surfaces, that is, the top and sides of each section are curved. This design greatly increases the inherent strength of each canopy section and substantially increases the resistance of the sections to bending or distortion.

While the invention has been described with a certain degree of particularity it is manifest that many changes may be made in the details of construction and the arrangement of components. It is understood that the invention is not to be limited to the specific embodiment set forth herein by way of exemplifying the invention, but the invention is to be limited only by the scope of the attached claim or claims, including the full range of equivalency to which each element or step thereof is entitled.

Claims

What is claimed:

1. An expandable cargo cover comprising:

a. a base;

b. a plurality of inverted U-shaped frames mounted on said base, and skin means to cover said frames;

c. a first of said frames fixed to said base;

d. the remainder of said frames of successively smaller size so that they nest one within the other;

e. a plurality of horizontal rollers mounted on said base in two parallel lines extending in the same direction from the two legs of said first frame, the remainder of said frames having their legs resting on said rollers, thus permitting said frames to be traversed along the lines of rollers;

f. a plurality of parallel guide means, to laterally guide the legs of said frames as they are traversed along said lines of rollers;

g. at least two traversing means parallel to each of said lines of rollers to traverse the smallest frame along said lines of rollers, one said means connected to each leg of said smallest frame; and

h. stop means attached to each of said frames to limit the motion of the adjacent frames to move from a first position where they are substantially superimposed to a second position where they are end-to-end.

2. The cargo cover as in claim 1 in which said traversing means comprising at least two parallel linear screw means supported by said base and nut means attached to each leg of said smallest frame.

3. The cargo cover as in claim 2 including means to synchronize the rotation of said at least two screw means.

4. The cargo cover as in claim 1 in which said traversing means comprises at least two linear chain elements respectively positioned along each line of rollers, and means to synchronize said chain elements.

5. The cargo as in claim 4 in which said two chain elements are part of a single chain loop having three portions, one along each line of rollers, and the third across the space between said lines of rollers.

6. The cargo cover as in claim 1 including means to seal the spaces between adjacent frames.

7. The cargo cover as in claim 1 including overhead carrier means supported on said base.