Skimmer protector with integral blow tube

Abstract

A skimmer protector with integral blow tube is a hollow, substantially closed, blow-molded body of resilient resin material having a cylindrical projection on one end with external screw threads for threading into the intake pipe of a swimming pool skimmer with an open integral tube running from and through said screw threaded portion to an opening elsewhere on its blow-molded body. The cylindrical projection on the body of the device is intended and designed to be threaded into the intake pipe or other part of a pool skimmer. When connected thereto, the skimmer protector is positioned to absorb/buffer the forces exerted by the expansion of ice as it freezes within the walled regions of the skimmer. The aforesaid integral tube serves to create a sealed air space between the tube and the outer walls. This sealed air space helps to resiliently stiffen the body of the skimmer protector, allowing it to better perform its function in absorbing ice expansion pressure. In addition, this sealed integral tube can be used as a blow-out tube to assist in the removal of water from the piping connected to the skimmer.

Description

[0001] This application claims the benefit of U.S. Provisional Application No. 60/259,652, filed on Jan. 4, 2001, which provisional application is incorporated by reference herein.

TECHNICAL FIELD

[0002] Our invention pertains to the general field of devices intended for the protection of swimming pools from freeze damage. More particularly, it deals with a skimmer protector for placement in the skimmer of a swimming pool.

BACKGROUND

[0003] Winter freeze-up of swimming pools causes considerable damage from ice expansion, particularly in the region of the skimmer for the pool. A prior invention of a skimmer protector (U.S. Pat. No. 3,552,267) of one of the co-inventors of this application recognized the special need for protection within the skimmer area and provided a simple, effective, and economical means for absorbing the expansion of ice in the skimmer to prevent damage to the skimmer. In the past, the protection provided by this invention has been supplemented by the use of blow-out tubes to force compressed air through skimmer piping in order to remove all water that might freeze in the winter and crack the piping. However, there has heretofore been no device that provided both features.

SUMMARY OF THE INVENTION

[0004] Our invention is a hollow, substantially closed, blow-molded body of resilient resin material having a cylindrical projection on one end with external screw threads for threading into the intake pipe of a swimming pool skimmer with an open integral tube running from and through said screw threaded portion to an opening elsewhere on its blow-molded body. The cylindrical projection on the body of the device is intended and designed to be threaded into the intake pipe or other part of a pool skimmer. When connected thereto, our invention is positioned to act as a skimmer protector and absorb/buffer the forces exerted by the expansion of ice as it freezes within the walled regions of the skimmer. Its function in this role is improved by the inclusion of the aforesaid integral tube, which serves to create a sealed air space between the tube and the outer walls of our invention. This sealed air space helps to resiliently stiffen the body of our invention, allowing it to better perform its function in absorbing ice expansion pressure. In addition, this sealed integral tube can be used as a blow-out tube to assist in the removal of water from the piping connected to the skimmer.

DRAWINGS

[0005] FIG. 1 shows an elevational cross-sectional view of a swimming pool skimmer with our invention installed in place.

[0006] FIG. 2 shows a cross-sectional view of a portion of the top of our invention with a plug positioned for insertion therein.

DETAILED DESCRIPTION

[0007] A skimmer (denoted generally by arrow 10) includes an inlet passageway 11 having a weir 12 leading to a walled chamber 14 having a cover 13 and an intake pipe 15 for drawing water from the pool to the pump and filter (not shown). Skimmer 10 can have many different shapes and sizes and can open in various ways to a pool. Also, various pipes can lead from intake pipe 15 to the pool filtration equipment. Most of the multitude of such skimmer arrangements can be protected by our invention.

[0008] Our invention has a blow-molded body 16 that is hollow, substantially closed, and formed of resilient resin material. Body 16 is generally cylindrical or formed into cylindrical sections as illustrated and has a diameter larger than intake pipe 15 where it is adjacent to intake pipe 15. The generally cylindrical shape of body 16 is preferred for ease of blow molding, but body 16 can have other shapes if desired.

[0009] In the preferred embodiment illustrated, a narrowed portion 16A of body 16 is also provided so as to allow the invention to be fitted into intake pipe 15 close to the side of walled chamber 14 without interference from a skimmer basket support rim 14A. In addition, gripping means in the form of raised semi-cylindrical projections or lugs 16B are provided around the top of body 16 to afford a better finger grip for screwing body 16 into intake pipe 15.

[0010] A cylindrical projection with external threads depends from body 16 for threading into the internal threads of intake pipe 15. Most swimming pool skimmers have a 1.5 inch tapered pipe thread in intake pipe 15. Others have a 2 inch tapered pipe thread in intake pipe 15. Thus, both a larger set of upper threads 17 (with a 2 inch diameter) and a smaller set of lower threads 18 (with a 1.5 inch diameter) are provided. However, different sized thread combinations can be provided as needed with the lower set of threads always, of course, being smaller than the upper set of threads. O-rings can be used with each set of threads 17, 18 to assure a complete seal when seated in intake pipe 15.

[0011] An integral tube 19 runs through the center of body 16. Integral tube 19 and body 16 are coaxial with integral tube 19 forming a hollow cylindrical channel in body 16 running between a lower opening at the base of lower threads 18 and an upper opening at the top of body 16. Integral tube 19 is adapted for use as a blow tube in clearing -pipe 15. Tube 19 can extend beyond body 16 and can also be provided with exterior caps and/or insertion plugs (such as plug 20) if desired to prevent water from entering pipe 15 via tube 19 when pipe 15 is not in use. Such plugs or caps can be held in place frictionally by the use of screw threading, by snap rings, or by other means and can be provided for either or both ends of tube 19.

[0012] When body 16 and tube 19 are joined, our invention has a sealed air space (denoted generally by arrow 21) between the outer surface of its body 16 and integral tube 19. This sealed air space 21 helps to resiliently stiffen the body of our invention, allowing it to better perform its function in absorbing ice expansion pressure. Many materials are suitable for forming body 16 and integral tube 19. However, our preferred materials are synthetic, thermal plastic resins, such as polyethylene. From a manufacturing standpoint, body 16 can be advantageously formed by blow molding and integral tube 19 via extrusion. These two parts can then be joined/welded at their lower edges and at their upper edges to form our invention.

[0013] During the molding process, an additional cylindrical protrusion or standoff is preferably formed on the flat surfaces present at the top and bottom of body 16. The top surface of each protrusion is reamed out, leaving only the walls of the protrusion. A tube of greater length than body 16 is then slipped through the openings that remain from the reamed out protrusions. Each end of the tube is then swaged, joined, or welded to the wall of the protrusion with heat and pressure so as to form integral tube 19. This results in a slightly raised ring or ridge 22 of plastic on the top and bottom surfaces of body 16. The raised ridge 22 of the top surface will accommodate a stopper such as plug 20 to prevent water from entering through the top of integral tube 19 after installation.

[0014] A second means of forming the top and bottom protrusions/stand-offs could be employed using a large size blow-pin during the molding process. This would create the raised walls on the top surface of body 16 for welding with integral tube 19 without going through the secondary process of reaming the protrusion. Additionally, the stand-off on the bottom surface of body 16 could be formed during the molding process by inserting a “dummy pin” into the mold cavity just prior to the injection of air used to give the part its shape.

[0015] The welding, joining, or swaging of body 16 with integral tube 19 is done using a heated ring. This heated ring captures both the wall of the protrusion and the wall of the integral tube 19. The two walls of plastic are joined by simultaneously melding and compressing them to form sealed raised, circular ridge 22 on the flat surface at both the top and bottom of the part. The heated “welding” ring is used in conjunction with a slightly tapered lead-in. This lead-in centers the heating ring and prevents integral tube 19 from collapsing or distorting during the “welding/joining”. The tapered lead-in is made of a non-conductive, non-stick material that allows it to be used as a centering device and partially as a swage block allowing the heating/welding process to occur primarily on the exterior of the part.

[0016] To install our invention, it is merely necessary to remove cover 13 and screw body 16 into pipe 15 via the appropriately sized screw threads provided. With body 16 threaded in place, intake pipe 15 is protected from ice and debris and body 16 extends above intake pipe 15 into the walled regions of skimmer 10 where it can be compressed by expanding ice to protect walls 14 from ice pressure. (The resilient materials forming body 16 and integral tube 19, as well as the air contained in air space 21, are readily compressed by expanding ice.) In addition, integral tube 19 is installed and ready to be used in clearing pipe 15 of any water that might freeze and cause damage. The flat upper surface of body 16 can accommodate air pressure devices or blower hoses of many different sizes. These are pressed against the top surface of body 16 in order to blow air through integral tube 19. Following this procedure, a plug 20 can be inserted to cap off the top of integral tube 19. After the ice season, body 16 is unscrewed and removed to ready the pool for use.

[0017] Persons wishing to practice the invention should remember that other embodiments and variations could be adapted to particular circumstances. Even though one point of view is necessarily chosen in describing and defining the invention, this should not inhibit broader or related embodiments going beyond the semantic orientation of this application but falling within the spirit of the invention. For example, many sizes and configurations of our invention can be used within the spirit of the invention. Moreover, our invention can also be produced using other techniques well known in the art such as heat sealing, spin welding, or ultrasonic welding.

Claims

1. A skimmer protector for use in a swimming pool having a skimmer including a walled region and an intake pipe, comprising:

a. a hollow, substantially closed body of resilient material;

b. one end of said body having a screw threaded cylindrical projection that can be threaded into said intake pipe;

c. a hollow blow-out tube in communication with said intake pipe extending from said intake pipe through said cylindrical projection to an outer opening located on said body; and

d. said body extending from said intake pipe to be compressibly disposed within said walled region.

2. The device of claim 1 wherein the outer opening is located at an end of the body opposite the cylindrical projection.

3. The device of claim 1 wherein a substantially sealed air space exists between the blow-out tube and said body.

4. The device of claim 1 wherein said body is generally cylindrical in shape.

5. The device of claim 4 wherein said body has a larger diameter than said intake pipe.

6. The device of claim 5 wherein a portion of said body arranged to confront a skimmer basket support rim is narrower in diametrical relationship to said cylindrical projection than a portion of said body adjacent to said cylindrical projection.

7. The device of claim 1 wherein the end of said body opposite the cylindrical projection has gripping means to afford a finger grip for screwing said body into said intake pipe.

8. The device of claim 1 further comprising a removable cap for sealing an end of said hollow blow-out tube.

9. The device of claim 1 wherein said screw threaded cylindrical projection has portions with different diameters, thereby enabling the device to be screwed into intake pipes having such different diameters.

10. The device of claim 1 wherein a raised rim surrounds the outer opening.

11. A skimmer protector with integral blow tube for use in a swimming pool having a skimmer including a walled region and an intake pipe, comprising a hollow body of resilient material having a cylindrical projection on one end with external screw threads for threading into the intake pipe of a swimming pool skimmer with an open integral blowout tube running from and through said screw threaded portion to an opening located at an end of the body opposite the cylindrical projection so as to form a substantially sealed air space between said blow-out tube and said body.

12. The device of claim 11 wherein said body is generally cylindrical in shape and has a larger diameter than said intake pipe.

13. The device of claim 12 wherein a portion of said body arranged to confront a skimmer basket support rim is narrower in diametrical relationship to said cylindrical projection than a portion of said body adjacent to said cylindrical projection.

14. The device of claim 13 wherein an end of the body opposite the cylindrical projection has gripping means to afford a finger grip for screwing said body into said intake pipe.

15. The device of claim 14 further comprising a removable cap for sealing an end of said hollow blow-out tube.

16. The device of claim 15 wherein said screw threaded cylindrical projection has portions with different diameters, thereby enabling the device to be screwed into intake pipes having such different diameters.

17. The device of claim 16 wherein a raised rim surrounds the opening.