Removable swimming pool cover

A removable swimming pool cover characterized by a plastic sheet or thermal blanket which floats on the surface of the water and is retained in position by a number of telescoping, spring loaded rods which are positioned between opposing sides of the pool is provided. The telescoping rods may also be provided with a locking handle which, when in the locked position, expands the rods lengthwise thus forcing the ends of the rods against the opposing sides of the pool to prevent removal.

BACKGROUND OF THE INVENTION 
The present invention relates generally to swimming pool covers and, more 
particularly, to a floating blanket or cover for a swimming pool that is 
retained in position with telescoping poles. 
A great many types and designs of covers for outdoor swimming pools have 
become commercially available. Early covers were provided to prevent trash 
and debris from entering the pools and to provide protection from 
accidental immersion for children and pets when the pools were left 
unattended. More recently, covers designed to lay or float on the surface 
of the water have become popular. Floating covers in the form of thermal 
blankets or pneumatic mattresses insulate a pool from loss of heat, from 
loss of volatile chemicals such as chlorine, and minimize evaporation of 
water. Many pool covers are constructed of materials which also provide 
for pool heating a resulting from solar heating. 
Most covers are simple sheets of plastic or other pliant material suspended 
over or floating on the surface of the water. Variations include 
mechanical operated covers of numerous kinds using rollers, tracks, 
hydraulic lifts, etc. to place rigid or flexible membranes above the 
surface of the water. An example is the pool cover disclosed by U.S. Pat. 
No. 2,958,872 issued to Fred J. Meyer, Jr., on Nov. 8, 1960. Meyer 
discloses a swimming pool cover characterized by stringers spaced apart in 
a desired arrangement and a screen material attached to span the areas 
between the stringers. The cover is held in place over the pool by 
spring-loaded hooks which are hooked in eyes anchored in concrete at 
intervals around the periphery of the pool. U.S. Pat. No. 3,683,428 issued 
to Lester Morris on Aug. 15, 1972, and U.S. Pat. No. 3,072,920 issued to 
John I. Yeilott on Jan. 15, 1963 provide examples of pool covers which are 
designed to float on the surface of the water. 
Use of the swimming pool covers described above, while providing adequate 
protection to the pool, also provide many difficulties. Mechanical 
operated devices save time, but they are expensive, are quite clumsy and 
often cannot be installed unless planned for during the original 
construction. The air-suspended cover disclosed by Meyer gives relatively 
poor insulation against heat losses, both because a plastic or canvas 
sheet is not a good insulator and a chimney effect occurs which sweeps 
moist warm air upward and out of the pool around the edges; radiation 
losses are also high. The time and energy required to cover and uncover 
the pool is often excessive. Plastic sheets and solar blankets which float 
on the surface of the pool are very susceptible to the wind, either being 
blown in a pile at one edge of the pool or blown completely out of the 
pool and into the yard. Further, most of the floating covers are not rigid 
enough to keep heavy or bulky items out of the pools nor do the pool 
covers described in the prior art off any protection from unauthorized use 
of the pool. 
SUMMARY OF THE INVENTION 
It is the principal object of the present invention to provide a swimming 
pool cover which floats on the surface of the water which cannot be blown 
about the pool or out of the pool by the wind. 
It is another object of the present invention to provide a swimming pool 
cover which is lightweight and easily installed and removed. 
It is yet another object of the present invention to provide a swimming 
pool cover which will provide for collection of solar heat and retention 
of heat to maintain the temperature of the water. 
It is a further object of the present invention to provide a swimming pool 
cover which can be locked in place to prevent unauthorized use of the 
swimming pool. 
A swimming pool cover according to the principles of the present invention 
is characterized by a pliant sheet or blanket of suitable material which 
floats on the surface of the pool and is retained in position by several 
spring loaded telescoping poles which extend from side to side of the 
pool. The poles which hold the blanket in place may also be provided with 
a locking handle which, when in the locked position, expands the poles 
lengthwise thus forcing the ends of the poles against the sides of the 
pool to prevent removal.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to an illustrative-embodiment of the present invention shown 
in FIG. 1, a plurality of hollow rigid rods 7a, 7b and 7c are arranged 
parallel to each other to span the pool 10 from side to side. The surface 
of the water 3 is covered by a suitable material 5 which is floated in 
position. The cover material 5 is attached to each of the rods 7 by a 
plurality of loops or slits 15 and 17 provided in the cover material 5. 
The rods 7 are retained in position between opposing walls 11 by the 
action of spring 15 (as shown in FIG. 2). 
The cover material 5 may be of any commercially available material which 
will float on the surface 3 of the water. Preferrably, the cover 5 will 
comprise a sheet of plastic material, particularly adapted to resist 
deterioration due to weather, and an over-layer of thin transparent 
plastic attached to one face of the sheet, the over-layer being folded at 
spaced intervals intermediate of its peripheral edge to form a quilted 
thermal blanket having a plurality of air-filled pockets. A type of 
material known as "bubble wrap" may be used as the cover material. The 
exposed surface of the plastic sheet may be covered by a reflective 
surface, and the opposite face of the sheet may be covered by a dark 
covered material to enhance heat retention and solar heating properties of 
the cover material 5. 
Referring now also to FIG. 2, the rods 7 are comprised of tubular sections 
constructed of a lightweight metal such as aluminum. The rod 7 can be 
telescoping in a manner similar to that of an automobile radio antenna, or 
may be made up of short sections which fit together to form a rod of the 
desired length. Each end of the rods 7 is covered with a protective boot 9 
made of hard rubber or other suitable material. The protective boot 9 will 
protect the pool walls 11 from any damage which may result from the rods 7 
contacting the pool wall 11. The end 13 of the boot 9 is coated with a 
soft, resilient material having a high coefficient of friction to allow 
the boot end 13 to grip the wall 11 of the pool without slippage when the 
boot end 13 is urged against the wall 11. A spring 15 is mounted within 
the center section of rod 7 in such a manner as to allow the rod 7 to be 
compressed in length to facilitate inserting the rod 7 between the walls 
11 of the pool 10, the restoring force of the spring 15 when compressed 
urges the rod ends 13 against the wall 11 with sufficient force to retain 
the rods 7, and hence the blanket 5, in place. With the cover 5 and the 
rods 7 in position in the pool 10, loops 17 are placed over hooks 19a and 
19b provided on each rod 7 to ensure that the blanket 5 is retained in 
position covering the entire surface 3 of the pool. 
Referring now to FIGS. 3a and 3b, rod section 7a is slidably inserted into 
rod secions 7b with lip 32 of rod section 7b abutting shoulder 30 of rod 
section 7a. One end of locking handle 31 is rotatable attached to bracket 
35 which is fixedly attached to rod section 7a adjacent shoulder 30. 
Locking handle 31 has two brackets 34 and 41 fixedly attached to it, 
bracket 34 approximately one-third of the length of locking handle 31 from 
the attached end and bracket 41 near the free end of the handle 31. 
Bracket 37 is fixedly attached to rod section 7b adjacent lip 32 and 
opposite bracket 34. Connecting linkage 33 is rotatably attached at 
opposite ends to brackets 34 and 37. Bracket 39 is fixedly attached to rod 
section 7b in such a position as to be opposite bracket 41 when locking 
handle 31 is rotated in the direction of arrow 45. 
When the pool cover has been installed in the pool, it may be locked into 
position by rotating locking handle 31 in the direction of arrow 41 
thereby forcing rod sections 7a and 7b apart a short distance 38 and 
against the walls 11 of the pool (as shown in FIG. 1) with great pressure. 
When the locking handle 31 is in the locked position (as shown in FIG. 3b) 
holes in brackets 39 and 41 will line up allowing a padlock 43 or other 
locking device to be inserted thus preventing any movement of the locking 
handle 31 and removal of the cover from the pool. 
While I have shown and described the preferred embodiment of my invention, 
I wish it to be understood that I do not confine myself to the precise 
details of construction herein set forth by way of illustration, as it is 
apparent that many changes and variations may be made therein, by those 
skilled in the art, without departing from the spirit of the invention or 
exceeding the scope of the appended claims.