US3574979A

US3574979A - Inflatable cover

Info

Publication number: US3574979A
Application number: US830974A
Authority: US
Inventors: John Y S Chan
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-06-06
Filing date: 1969-06-06
Publication date: 1971-04-13
Anticipated expiration: 1988-04-13

Abstract

A cover is formed of a sheet of substantially liquid impervious flexible material. The sheet of material is wound upon a support means, and one end of the sheet of material is secured to a movable carriage. Drive means is connected with the carriage for selectively moving it toward and away from the support means. Inflatable means in the form of tubular members are secured to the underside of the sheet of material, and means is provided for selectively inflating and deflating the inflatable means.

Description

United States Patent John Y. S. Chan 10065 Elm Ave., Loma Linda, Calif. 92354 [21 Appl. No. 830,974

[22] Filed June 6, 1969 [45] Patented Apr. 13, 1971 [72] Inventor [54] INFLATABLE COVER 14 Claims, 7 Drawing Figs.

52 U.S. Cl 52/2, 4/ 172.12 51 Int. Cl E04g 11/04 [50] Field of Search 52/2; 4/l72.l1,172.12,172.13, 172.14

[56] References Cited UNITED STATES PATENTS RE25,078 l 1/1961 McGuire 4/172.14 2,754,836 7/1956 Darby 52/2 2,958,083 11/1960 Shook et al.... 4/l72.l4 3,019,450 2/1962 Karasiewicz 4/ 172.14

3,050,743 8/1962 Lamb 4/172.14 3,074,079 l/1963 lsaacson 4/172. 1 4 3,076,975 2/1963 Lamb 4/l72.l4 3,300,910 1/1967 lsaac 52/2 3,366,977 2/1968 Koehler... 4/172. 1 2 3,433,470 3/1969 Erke 52/2X 3,501,783 3/1970 Broadman 4/172.14

Primary Examiner-Frank L. Abbott Assistant Examiner-Sam D. Burke, 111 Attorney-Shoemaker and Mattare ABSTRACT: A cover is formed of a sheet of substantially liquid impervious flexible material. The sheet of material is wound upon a support means, and one end of the sheet of material is secured to a movable carriage. Drive means is connected with the carriage for selectively moving it toward and away from the support means. Inflatable means in the form of tubular members are secured to the underside of the sheet of material, and means is provided for selectively inflating and deflating the inflatable means.

Patented. April 13, 1971 2 Sheets-Sheet 1 INVENTOR JOHN Y. S. CHAN wwwww M /ZMJWMI W ATTORNEYS Patented April 13, 1971 3,574,979

2 Sheets-Sheet 2 ATTORNEYS INFLATABLE coves BACKGROUND OF THE INVENTION The present invention is directed to a cover which is adapted to cover relatively large areas. While the structure may be employed for covering either liquids or solids, it is particularly suited for use in covering large bodies of liquid.

The invention is especially directed toward applications such as covers for pools or liquid utilized for producing salt or other substances by solar evaporation. In such applications, the area to be covered is often of very large dimensions, and it is generally impractical to attempt to cover such large areas. As a result, when it rains the pool of liquid is undesirably diluted.

It is accordingly desirable to provide a means for covering very large areas. In order to be practical, such covers must be of relatively inexpensive construction, and yet at the same time must enable effective coverage of large areas in a small amount of time, and further enable the cover to be retracted quickly when no longer in use.

SUMMARY OF THE INVENTION The present invention provides a cover in the form of a sheet of substantially liquid impervious flexible material which can be manufactured very economically of plastic or similar substance.

This sheet of material is nonnally stored on a supply roll of a support means when in retracted position. One end of the sheet of material is secured to a movable carriage which is operatively connected with a drive means which enables the carriage to be moved away from the fixed support meansf Accordingly, when it is desired to cover a large area, the drive means is energized to move the carriage away from the support means thereby drawing the cover over the area to be covered.

Inflatable means is secured to the underside of the cover. This inflatable means may serve a number of separate functions. Firstly, it serves to rigidify the sheet of material and to support intermediate portions thereof. Secondly, the inflatable means serves to provide a normal extended configuration to the sheet of material such that it slopes downwardly toward the opposite edges thereof whereby rain readily drains off of the cover.

Thirdly, the inflatable means is adapted to float on a body of motor 20 which is adapted to drive the roll in one direction as hereinafter described. A manually operable control 22 is provided for energizing drive motor 20.

The cover itself comprises a sheet of substantially liquid impervious flexible material. This sheet may be formed of any suitable inexpensive relatively strong substance such as a polyethylene film, which may have a thickness on the order of 4 mils.

As seen in FIG. 2, the sheet 30 is adapted to be wound on storage reel or supply roll 18 when the cover is'in the retracted position. A roll 34 is normally biased toward roll 18 byv tension spring means 36, the purpose of roll 34 being hereinafter fully described.

One end of the cover is secured to roll 18, and the opposite end of the cover is secured at 40 to a transversely extending carriage 42. Carriage 42 includes depending portions 44 at opposite ends thereof and supports the opposite end of the cover in elevated position. Antifriction means 46 in the form of wheels are supported at the lower ends of portions 44 whereby the carriage is freely movable toward and away from support means 14.

Wheels 46 are movable within troughs 50 disposed at opposite sides of the pool and extending longitudinally thereof, these troughs forming portions of a drainage system for receiving rain water forming portions of a drainage system for receiving rain water which drains off of the cover when it is disposed in overlying relationship to the body of liquid 12.

As seen most clearly in FIG. 4, inflatable means is secured to the underside of the sheet 30, this inflatable means including a first elongated tubular member 60 which is closed and sealed at the end 62 thereof, the opposite end 64 thereof opening to an inflation means 66 in the form of an air pump or liquid thereby supporting the cover means on the surface of the underlying liquid body.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a top perspective view partly broken away;

FIG. 2 is a sectional view taken substantially along line 2-2 of FIG. I looking in the direction of arrows;

FIG. 3 is a view similar to FIG. 2 illustrating the components thereof in a different operative position;

FIG. 4 is a top view of the structure shown in FIG. 3;

FIG. 5 is a sectional view taken substantially along line 5-5 of FIG. 3 looking in the direction of the arrows;

FIG. 6 is a top perspective view of a modified form of the invention; and

FIG. 7 is a sectional view on an enlarged scale taken substantially along line 7-7 of FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings wherein like reference characters designate corresponding parts throughout the the like.

The inflatable means includes a second elongated tubular member 68 which is closed and sealed at the end 70 thereof, the opposite end thereof opening into air pump 66. Each of tubular members 62 and 68 may be formed of a suitable material such as polyethylene tubing of a thin wall construction.

Tubular member 60 extends longitudinally along the medial portion of the sheet of material while tubular portion 68 includes portions extending at an oblique angle to tubular member 60 whereby tubular member 68 extends in a zigzag arrangement along the length of the cover. The tubular members may be secured in any suitable manner to the undersurface of the sheet of material as by welding or the like in a well-known manner.

It should also be noted as seen in FIGS. 4 and 5 that tubular member 60 is of substantially great r cross-sectional dimension or diameter than tubular member 68. As a result, when the cover is in its extended protective position, the cover will be supported so that the upper surface thereof slopes from the medial portion thereof downwardly toward the opposite edges whereby rain water or the like will drain outwardly and off of the cover.

Reinforcing means is provided at the opposite edges of the cover and includes a pair of

high tensile tapes

74 and 76 secured to the upper surface of the cover at the opposite edges thereof, these high tensile tapes being suitably secured to the sheet of material as by welding or the like.

A harness 80 in the form of cable or the like is secured to carriage 42, this harness in turn being connected to a cable 82 which is wound about a winding drum 84. This winding drum comprises a drive means for moving the carriage away from support means 14. Drum 84 is rotatably supported by spaced support portions 86, and an electric motor is provided for selectively driving the winding drum. A manual control 92 is provided for driving the winding drum as desired.

A first microswitch is supported by support means 14 and is operatively connected with motor 20 for deenergizing the motor when the microswitch is closed. A second microswitch 102 is supported by one of the support members 86 and is operatively connected with electric motor 90 for deenergizing'motor 90 when microswitch 102 is closed.

Carriage 42 carries a first contact portion 104 adapted to close microswitch 100. A second contact 106 is also carried by carriage 42 and is adapted to close microswitch 102.

In operation of the construction shown in FIGS. 1-5, the cover is nonnally stored in the position shown in FIG. 2 wherein it is wound about supply roll 18, and carriage 42 is at the limit of its movement to the left as seen in this FIG. It is apparent that the size of the stored roll depends on the size of the area to be covered. In a typical example, the roll may be 14 feet wide and 1,000 feet long.

When it is desired to extend the cover into its protective position, drive motor 90 is energized by control means 92 whereupon drum 84 will wind up cable 82 thereon. This draws the carriage away from the support means and unwinds the cover from the supply roll. The reinforcement means extending along opposite edges of the sheet of material enables the sheet of material to be easily unwound. Supply roll 18 is free to rotate in a counterclockwise direction as seen in FIG. 2 and is driven in a clockwise direction. On the other hand, drum 84 is free to rotate in a clockwise direction and is driven in a counterclockwise direction.

As the cover is unwound from the supply roll, air pump 66 is operated to inflate both of the tubular means associated therewith. These tubular means will thereby float on top of the body of liquid therebelow.

Carriage 42 will continue to move to the right as seen in FIG. 2 until it reaches the position shown in FIG. 3 whereupon microswitch 102 is closed and drive motor 90 is deenergized.

In the extended position, the cover will be disposed in overlying relationship to the pool and the opposite side edges thereof as seen in FIG. 5 are disposed adjacent to troughs 50 whereby any rain water draining off of the cover will be carried away by the drainage system.

When it is desired to retract the cover, the air pump is turned off and motor is energized to draw the sheet of the material back into supply roll 18. This causes the carriage 42 to move toward the support means. As the sheet of material is drawn into supply roll 18, roll 34 engages the tubular means secured to the undersurface of the sheet of material so as to force the air out of such tubular means whereby the tubular means is automatically deflated.

Carriage means 42 continues to move to the left until microswitch 100 is closed whereup drive motor 20 is deenergized. The cover is then again in its fully retracted position exposing the body of liquid to the sun.

Referring now to FIGS. 6 and 7, a modified form of the invention is illustrated. Portions of this construction are identical with that previously described, and similar parts have been given the same reference numerals primed.

In this form of the invention, the inflatable means secured to the undersurface of the sheet of material is modified. Sheet corresponds to sheet 30 previously described, and a first tubular member 100 extends longitudinally of the sheet of material along the medial portion thereof. Additionally, a pair of further

tubular members

112 and 114 are secured to the undersurface of the sheet of material and extend in spaced parallel relationship to tubular member 110.

Each of these tubular members may be of construction similar to those previously described, one end thereof being closed and sealed and the opposite ends thereof being open for connection to suitable inflating means.

It will be noted as seen in FIG. 7 that tubular member 110 is of substantially greater cross-sectional dimension or diameter than

tubular members

112 and 114 so as to provide the desired configuration to the extended cover so that rain water or the like will drain downwardly from the central portion thereof towards the opposite edges.

As seen in FIG. 6, an air pump 120 is supported adjacent winding drum 84' rather than being supported on the carriage means as in the previously described embodiment. This air pump is adapted to be connected to the open ends of tubular members 110, I12 and 114 when the cover has been moved into its fully extended position. The tubular inflatable members are inflated in this forrn of the invention only after the cover has been moved into its fully extended operative position.

As this invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, the present embodiment is therefore illustrative and not restrictive, since the scope of the invention is defined by the appended claims rather than by the description preceding them, and all changes that fall within the 'metes and bounds of the claims or that form their functional as well as conjointly cooperative equivalents, are therefore intended to be embraced by those claims.

Iclaim:

1. An inflatable cover comprising a thin flexible sheet of substantially liquid impervious material, support means for supporting said sheet of material, said support means including a storage reel to which one end of said sheet is attached and upon which said sheet is adapted to be wound and stored, the other end of said sheet of material operatively connected to carriage means, means connected to said carriage means for drawing said sheet of material from said storage reel, said carriage means supporting said other end of said sheet in elevated position, inflatable means secured to said sheet of material, means for inflating said inflatable means, and roller means adjacent to and cooperating with said reel means for deflating said inflatable means as it is wound upon said storage reel.

2. A cover as defined in claim 1 wherein said inflatable means includes a tubular member secured to the underside of said sheet of material.

3. A cover as defined in claim 2 wherein said tubular member extends longitudinally of said sheet of material, and including a second tubular member secured to the underside of said sheet of material, said second tubular member being of smaller cross-sectional dimension than said first-mentioned tubular member.

4. A cover as defined in claim 3 wherein said second tubular member includes portions extending at an oblique angle to said first tubular member to define a substantially zigzag arrangement.

5. A cover as defined in claim 3 wherein said tubular member of smaller cross-sectional dimension is disposed in spaced parallel relationship to said first-mentioned tubular member.

6. A cover as defined in claim 1 including reinforcing means disposed at the opposite side edges of said sheet of material and extending longitudinally thereof.

7. A cover as defined in claim 1 including drive means operatively connected with said support means for moving said support means.

8. A cover as defined in claim 1 including resilient biasing means for normally biasing said roller means toward the adjacent portion of said inflatable means.

9. A cover as defined in claim 1 wherein said carriage means includes antifriction means supporting said carriage means for movement relative to said support means.

10. A cover as defined in claim 1 wherein said means for inflating the inflatable means is carried by said carriage means.

11. A cover as defined in claim 1 including drive means for selectively moving said carriage means.

12. A cover as defined in claim 11 including limit switch means for deenergizing said drive means upon predetermined movement of said carriage means.

13. A cover as defined in claim 11 wherein said means for inflating the inflatable means is supported adjacent said drive means.

14. A cover as defined in claim 1 wherein said inflatable means supports the sheet of material so that it slopes downwardly toward the opposite side edges thereof, and drainage means for receiving material draining off of said sheet of material, said drainage means extending adjacent opposite side edges of said sheet of material.