SPAS

DESCRIPTION

BACKGROUND OF THE INVENTION

[Para 1 ] The present invention generally relates to vacuum relief valves. More particularly, the present invention relates to an adjustable vacuum relief safety valve system for use in swimming pools, spas and the like which causes the pump to lose its prime and be shut off if a pre-determined vacuum level is reached in the pump system, such as when an object obstructs the pool's drain. [Para 2] To maximize enjoyment and maintain proper sanitary conditions, swimming pools must be constantly cleaned of debris, dirt and other contaminants. Pools of various types are known to have one or more suction inlets where pool water is sucked along the line via a pump to filtration, aeration, chemical treatment and other type of equipment prior to being returned to the pool via one or more return outlets.

[Para 3] In more recent pool designs, some of the suction inlets are positioned in the bottom or lower region of the pool. Very recently developed pool systems, known as in-floor cleaning systems, have one or more suction inlets which suck pool water therethrough and any debris of pollutants entrained therein are cleaned from the water by being pumped through a filtration and/or treatment station. As with all pools and spas, a high rate of water flow must be achieved in order to maintain an acceptable level of cleanliness. Consequently, a high capacity pump must be employed to draw the water from the pool, with a relatively larger pump generally being required as the size of the pool increases. [Para 4] Some of the water inlets of such drains have relatively small opening areas and, when large volumes of water being pumped therethrough, very high suction forces at the inlet can be induced. These forces can be so extreme that if a pool user contacts the inlet by any part of their body, they can be held thereagainst, unable to be dislodged, even by force. Such vacuum forces have become so excessive that there have been cases of disembowelment. When the suction inlet is located at or more adjacent to the bottom of a pool, the user can thus be submerged with the risk of drowning or other grievous injury. When such an incident occurs, the vacuum level in the drain line and pool's pump rises sharply.

[Para 5] Occurrences of this type of accident have caused the pool industry to look for solutions that prevent an individual, such as a child, from becoming entrapped at the drain. Some approaches have been by modifying the drain's construction. Examples of this approach include U.S. Patent No. 5,809,587 to Fleischer and U.S. Patent No. 6,295,661 to Bromley. However, these devices are fairly complex and expensive to produce. Moreover, these approaches are only acceptable for new pool construction, and are not capable of being incorporated as a retrofit into existing pools and spas.

[Para 6] Yet other approaches involve the insertion of a safety valve into a suction line of the filtration and circulation system. Examples of these include, U.S. Patent No. 5,682,624 to Ciochetti; U.S. Patent No. 6,591 ,863 to Ruschell et al.; U.S. Patent No. 6,486,052 to McKain et al.; and U.S. Patent No. 6,687,923 to Dick et al. However, this approach also presents many drawbacks. First, such piping is typically submerged below the ground and often encased in or otherwise positioned below concrete. Thus, access to the pipes is not readily obtained unless the safety valve is incorporated into the system when the swimming pool is built. Otherwise, the valves require that the pipe be cut so that the safety valve device can be inserted therein. Cutting these lines increases the opportunity for air leakage in the suction side. Moreover, such installation typically requires professionals having the appropriate tools and ability to install such safety devices. A problem with all such "in-line" systems is that they are typically not close to the pump. The closer one gets to the pump, the better the safety device responds to emergencies.

[Para 7] Yet other prior art approaches utilize electric controls to monitor and control the amount of suction within a line or within the pump. For example, U.S. Patent Nos. 6,059,536 and 6,342,841 both to Stingl disclose such systems. Other systems include U.S. Patent No. 5,947,700, U.S. Patent No. 6,1 71 ,073 and U.S. Patent No. 6,468,052 all to McKain. The systems taught in these Patents electrically sense and analyze negative pressure levels within the system and compare the sensed levels with acceptable norms programmed into the electric circuitry. If the negative pressure norms are exceeded, air is introduced into the system, the pump is deactivated, and/or alarms and the like are activated. However, these systems present several drawbacks. Typically, these systems must be adjusted in the field for the particular pump system. Moreover, these systems are relatively expensive and complex.

[Para 8] Accordingly, there is a continuing need for a pool safety valve system which overcomes the deficiencies described above. The safety valve should be capable of being attached directly to the pump. The safety valve system should also be simple enough in design so as to be manufactured inexpensively and installed by the pool owner. The safety valve system should also be capable of being used in existing pools as a retrofit and adjustable to the pump of the existing pool. The present invention fulfills these needs and provides other related advantages.

SUMMARY OF THE INVENTION

[Para 9] The present invention resides in an adjustable vacuum relief safety valve system for human-occupiable pools. As used herein, human-occupiable pool means any residential or commercial swimming pool, wading pool, hot tub, spa, Jacuzzi or the like. Such human-occupiable pools have a water circulation system including an intake line, such as from drains from the pool, and a water output line fluidly connected to a pump. As is well known, the pump serves to circulate the water, such as through a filtration system.

[Para 10] The adjustable vacuum relief safety valve system of the present invention comprises a housing comprised of a first shell portion and a second shell portion which cooperatively define an inner chamber. The first shell portion of the housing has an aperture in fluid communication with the pump and the inner chamber of the housing. An air inlet aperture is formed in the second shell of the housing and open to ambient air. Typically, the housing is directly attached to the pump. In a particularly preferred embodiment, the housing is threadedly attached to a drainage port of the pump.

[Para 1 1 ] A sealing element is disposed within the housing inner chamber.

Typically, the sealing element includes at least one leg biased against a wall of the inner chamber. A spring may be used to bias the at least one leg against the wall of the inner chamber.

[Para 1 2] A spring is disposed within the inner chamber and adapted to bias the sealing element against the air inlet aperture of the second shell so as to prevent ambient air from entering the inner chamber and into the pump during normal pressure conditions. However, the spring can be compressed to permit the sealing element to be pushed away from the air inlet aperture of the second shell and permit the flow of ambient air into the inner chamber and into the pump, such that the pump loses its prime during elevated negative pressure operating conditions, such as when a drain of the human-occupiable pool is obstructed.

[Para 1 3] The first shell and the second shell of the housing are connected so as to be adjustably moved toward and away from one another so as to alter the compression of the spring and adjust for pump characteristics. In one embodiment, the first shell and the second shell are threadedly attached to one another.

[Para 14] In a preferred embodiment, a visually readable pressure gauge is operably connected to the housing so as to read a pressure within the inner chamber. This may be done by connecting the pressure gauge to a port of the housing in fluid communication with the inner chamber of the housing. The first and second shells of the housing are adjustably connected to one another until a reading from the pressure gauge is generally constant. This indicates that the vacuum release safety valve system has been adjusted properly to that particular pump to reflect its normal operating pressure conditions. [Para 1 5] In one embodiment, the system includes an electronic circuit, including a switch actuatable by movement of the sealing element, wherein actuation of the switch activates the electronic circuit to shut off power to the pump. Typically, the switch includes a depressable member engageable with a portion or extension of the sealing element so as to actuate the switch. The electronic circuit preferably includes a timer circuit configured to temporarily shut off power to the pump, and after a predetermined period of time restore power to the pump. The electronic circuit may also include delay circuitry configured to delay shutting off power to the pump during a predetermined pump start-up period.

[Para 1 6] Other features and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[Para 1 7] FIGURE 1 is a side perspective view of an adjustable vacuum relief safety valve embodying the present invention, with first and second shells of the housing being completely closed towards one another;

[Para 1 8] FIGURE 2 is a side perspective view of the adjustable vacuum relief safety valve of FIG. 1 , illustrating the first and second shells moved away from one another, in accordance with the present invention;

[Para 1 9] FIGURE 3 is a rear and side exploded perspective view of the vacuum relief safety system of FIG. 1 , illustrating various component parts thereof;

[Para 20] FIGURE 4 is a front and side exploded perspective view of the vacuum relief safety device of FIG. 1 ;

[Para 21 ] FIGURE 5 is a front elevational view of the vacuum relief safety valve system of the present invention;

[Para 22] FIGURE 6 is a partially sectioned view of the vacuum relief safety valve system of FIG. 5;

[Para 23] FIGURE 7 is a side sectional view of the vacuum relief safety system, illustrating a sealing element thereof in a closed position;

[Para 24] FIGURE 8 is a sectioned view similar to FIG. 7, but illustrating the sealing element in an open position;

[Para 25] FIGURE 9 is a side perspective view of another embodiment of the vacuum relief safety valve of the present invention; [Para 26] FIGURE 1 0 is a side perspective view of the vacuum relief safety valve of FIG. 9, with the shells of the housing being adjusted away from one another, in accordance with the present invention;

[Para 27] FIGURE 1 1 is a rear and side exploded perspective view, illustrating various components of the vacuum relief safety valve;

[Para 28] FIGURE 1 2 is a front and side exploded perspective view of the vacuum relief safety valve;

[Para 29] FIGURE 1 3 is a partial cross-sectional view taken generally along line

1 3-1 3 of FIG. 9, illustrating the device of the present invention during normal pump operating conditions;

[Para 30] FIGURE 1 4 is a cross-sectional view taken generally along line 1 4-1 4, illustrating arrangement of inner components of the device during normal pump operating conditions;

[Para 31 ] FIGURE 1 5 is a partially cross-sectional view similar to FIG. 1 3, but with the pump operating under abnormal, and elevated negative pressure conditions;

[Para 32] FIGURE 1 6 is a cross-sectional view taken generally along line 1 6-1 6 of FIG. 1 5, illustrating the internal components in an elevated negative pressure condition, including actuation of a switch thereof;

[Para 33] FIGURE 1 7 is a partially sectioned view of a pump having a vacuum relief safety valve system embodying the present invention attached to a drainage port thereof; [Para 34] FIGURE 1 8 is a partially sectioned view of a pump having the vacuum relief safety valve system of the present invention attached directly to another portion of the pump, in accordance with the present invention;

[Para 35] FIGURE 1 9 is a diagrammatic view of a pump having the vacuum relief safety valve system of the present invention attached to a drainage port thereof, and operably connected to a control circuit, in accordance with the present invention;

[Para 36] FIGURE 20 is a diagrammatic view of an electric circuit used in accordance with the present invention; and

[Para 37] FIGURE 21 is a diagrammatic view of the steps taken in accordance with one mode of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [Para 38] As shown in the accompanying drawings for purposes of illustration, the present invention resides in an adjustable vacuum relief safety valve system, generally referred to by the reference number 1 0, for a human-occupiable pool. As used herein, "human occupiable pool" includes residential and commercial swimming pools, wading pools, spas, Jacuzzis, hot tubs and the like. Such human-occupiable pools have a water circulation system which includes a water intake line and a water output line fluidly interconnected with a pump. As will be more fully described herein, the present invention, under abnormal elevated negative pressure conditions, introduces ambient air into the pump such that the pump loses its prime. In one embodiment, the invention also at least temporarily shuts off power to the pump.

[Para 39] With reference now to FIGS. 1 -4, a vacuum relief safety valve system 10 embodying the present invention is shown. The safety valve system 10 includes a housing comprised of a first shell 1 2 and a second shell 14, which are adjustably attached to one another. The first and second shells 1 2 and 14 of the housing are configured to be connected to one another in an adjustable manner such that the axial distance therebetween can be altered in a selective manner. In a particularly preferred embodiment, the first shell includes interior threads 1 6, as illustrated in FIG. 4, and the second shell includes a portion having mating exterior threads 27, as illustrated in FIGS. 2 and 3. In a particularly preferred embodiment, the second shell includes hand grip bumps 20, or the like, to facilitate the manual screwing and unscrewing of the second shell 14 to the first shell 1 2. When the second shell 1 4 is adjusted appropriately, as will be more fully described herein, one or more bolts 1 8 are inserted through a slot or aperture 1 9 of the second shell and into a corresponding tie bolt receiving threaded aperture 33. As the location of the second shell is typically unknown, in a preferred embodiment, a series of semi-circular slots 1 9 are formed within a circumferential edge of the second shell such that the bolt 1 8 can be aligned with the receiving threaded aperture 33 of the first shell.

[Para 40] As illustrated in FIGS. 7 and 8, the first and second shells 1 2 and 1 4 cooperatively form an inner chamber 32 therebetween. The size of the inner chamber is adjusted per the adjustable connection of the first and second shells 1 2 and 14, as described above. The inner chamber 32 is in fluid communication with a pump 79 of the circulation system. Typically, the first shell 1 2 includes an exteriorly threaded shank 26 having an aperture 30 which provides fluid communication between the inner chamber 32 and the pump 79. As illustrated in FIG. 1 9, the relief valve system 1 0 of the present invention is preferably attached to a drainage plug outlet 1 68 of the pump. As illustrated in FIG. 1 7, in some cases it is desirable to have an extension conduit 1 67 interconnecting the drain plug port 1 68 and the relief safety valve system 10. With reference now to FIG. 1 8, the drain port 1 68 is shown with its plug 1 70 inserted therein, as is typically the case without the invention. In this embodiment, the vacuum relief safety valve system 10 has been directly attached to another portion of the pump 1 60. This may be by threaded interconnection with the exterior threads 28 of the first shell extension 26, or by other means, such as the use of adhesives or the like. In the invention, it is preferred that the vacuum relief safety valve system 10 be directly attached to the pump so that ambient air can be introduced into the pump as quickly as possible such that the pump loses its prime and the obstruction can be removed from the drain of the pool. Since an air-tight seal must be formed between the system 10 and the pump, an O-ring 34 or the like is typically provided between the back plate of the first shell 1 2 and surrounding the extension 26 so as to be disposed between the first shell 1 2 and the adjoining pump face. [Para 41 ] As illustrated in FIGS. 1 , 4 and 5-8, one or more apertures 22 and 23 are formed in the second shell 14 of the housing which are in fluid communication with ambient air. Absent any obstruction, ambient air is allowed to flow through the one or more holes 22 and 23 of the second shell of the housing 14, through the inner chamber 32, and through the outlet aperture 30 of the first shell 1 2 and into the pump 1 60. In a particularly preferred embodiment, a plurality of apertures 23 are formed which are relatively small in size so as to prevent insects or other debris from entering therein. It will also be understood that a mesh material or the like can be used to prevent such material from entering into the system 10. The apertures 22 and 23 are formed in the front face 24 of the second shell 1 4, as illustrated in FIG. 4.

[Para 42] With reference now to FIGS. 3-8, a sealing element 36 is disposed within the housing and biased upwardly against the upper end wall 24 of the second shell 1 4 so as to seal the air inlet aperture 22. O-ring 37 engages radially to form a seal between sealing element 36 and the inside of the housing at ledge 39 to form a piston like mechanism that creates pneumatic compensation for any existing pool set-up. Also, this dual sealing will work as a primary air and fluid tight seal. A gasket, such as the illustrated rubber O-ring 38, may be disposed between the housing and the sealing element 36 so as to create a back-up air and fluid-tight seal. In a particularly preferred embodiment, the sealing element 36 is of a disc-figuration, as illustrated in FIGS. 3 and 4, so as to include an upper plate portion 40 sized to extend into the air inlet aperture 22, and preferably having a beveled skirt which forms a conical sealing surface for better air tight sealing when it engages the O-ring 38. One or more legs 44 extend outwardly from the sealing element 36 so as to flex against an inner wall of the housing, as will be more fully described herein. [Para 43] An inner based surface of the first shell 1 2 includes a seat 46 which supports a spring 48 thereon. The spring is a compression spring so as to extend outwardly away from the base plate 1 2 and contact the sealing element 36 so as to bias it into engagement with the upper wall 24 of the second shell 14 so as to seal the air inlet aperture 22. The seat 46 preferably includes a cylindrical guide 50 which extends into the spring 48 and properly positions the spring 48. The seat 46 preferably includes one or more channels 52, as will be more fully described herein.

[Para 44] With reference now to FIGS. 4-8, it is seen how the channels 52 extend through the seat 46 and towards the aperture 30 of the first shell 1 2. This allows air to flow from the housing into the pump, even when the spring 48 is completely compressed. The inner wall of the housing typically also includes at least one depression 53, typically in the form of elongated flutes or channels, which permit air to pass through the housing around the sealing element 36 when the sealing element 36 is moved into the inner chamber, as illustrated in FIG. 8. [Para 45] With reference now to FIG. 7, the sealing element 36 is shown with at least a portion, typically the end, of the legs 44 in engagement with the surface of the inner wall 56 of the housing. The flexed legs 44 serve as a guide for the sealing element 36. Moreover, as will be more fully described herein, the legs 44 serve to delay the closure of the sealing element 36, or can be used to create a situation where a manual resetting is required.

[Para 46] With reference to FIGS. 1 -4, in a particularly preferred embodiment, a visually readable pressure gauge 1 7 is operably connected to the housing so as to read a pressure within the inner chamber 32. Typically, the pressure gauge 1 7 is connected to a port 54 which extends through the first shell and into the inner chamber. A pressure gauge 1 7 illustrating a rotatable dial is illustrated, although it will be appreciated that other pressure gauges, such as an electronic pressure gauge, could be used.

[Para 47] In accordance with the present invention, the vacuum relief safety valve system 10 of the present invention is adjustable so as to accommodate the different characteristics of pumps, such as the difference between different types of pumps, the power of the pump, etc. This is accomplished by attaching the system 10 to the pump of the pool water circulation system, and adjusting the second shell, either by rotating the second shell clockwise or counterclockwise so as to tighten or loosen the second shell to the first shell, and thus adjust the axial distance therebetween, and compress or decompress the spring and the sealing element until the system 1 0 is adjusted for the normal operating condition of the pump that it is being attached to. This can be easily visually seen with the pressure gauge. If the dial, for example, on the pressure gauge provides an erratic and changing reading, then the system 10 needs to be adjusted by rotating the second shell 1 4 until a generally constant reading is achieved. When this occurs, the installer will know that the system 10 has been properly adjusted for the characteristics, such as horsepower, of that particular pool pump. The bolts 1 8 can then be used to lock the first and second shells 1 2 and 14 in that position. This will prevent tampering or inadvertent adjustment of the system 10. Of course, such adjustability is highly desirable as the same system 10 can be used in association with a variety of different pumps.

[Para 48] With reference now to FIGS. 1 -8, the general operation of the adjustable safety valve system 1 0 will now be explained. As illustrated in FIG. 7, the at rest position of the sealing element 36 is biased outwardly such that the upper plate portion 40 engages the O-ring 38 so as to effectively seal the air inlet apertures 22 and 23. In this position, O-ring 37, resting in groove 42, engages inner wall 39 for air tight sealing. During normal pump operating conditions, this is the standard position of these elements. For example, when the safety valve 1 0 is connected to the pump 1 60, water from the pump enters aperture 30 and fills the inner chamber 32 of the housing. The sealing element 36 is biased outwardly so as to seal the inner chamber 32 of the safety valve 1 0 from ambient air while the pump is in normal operation, or is off.

[Para 49] However, with reference to FIG. 8, when a drain or inlet of the swimming pool is obstructed, such as if a child were to be held at the drain port, the vacuum or negative pressure within the pump 1 60 significantly increases, causing the sealing element 36 to be pushed by ambient atmosphere into the inner chamber 32, as illustrated. The spring 48 is compressed by such action, and air (illustrated by the directional arrows in FIG. 8) flows into the safety valve 10 through air inlet apertures 22 and 23, over sealing element 36, and through channels 53 and into the inner chamber 32, and eventually through aperture 30 and into the pump. This causes the pump to quickly lose its prime. As can be seen in FIG. 8, even when the spring 48 is completely compressed, such that the coils rest upon one another, the air is still able to pass into aperture 30 due to the channels 52 formed in the seat 46.

[Para 50] When the pump loses its prime, the child or other object is able to be removed from the drain or inlet. This causes the high vacuum condition within the pump to return to normal, and thus the spring 48 to begin to bias the sealing element 36 upwardly again.

[Para 51 ] The sealing element 36 and legs 44 can be comprised of a resilient material, such as nylon, causing the legs 44 to be biased outwardly against the housing inner wall. However, it has been found that if the valve is open and closed several times, such as a dozen times or more, the legs 44 can be worn down. Other materials, such as Teflon, enable the sealing element 36 to be opened and closed numerous times, such as one hundred times or more. However, it has been found that many of these materials, while more durable, do not have the resilient qualities of the nylon material. Accordingly, in a preferred embodiment, a spring, such as the illustrated flat spring 63, is disposed within the legs 44, causing them to be biased outwardly against the housing wall. The legs 44, as indicated above, serve not only as a guide for the sealing element 36, but also serve to slow the closing of the sealing element 36. As illustrated in FIGS. 7 and 8, the flush end of the second shell 58 can form a ledge 58 which can be engaged by an end 59 of the legs such that the legs lock the sealing element 36 in place if the sealing element 36 is pushed sufficiently far into the inner chamber of the housing. [Para 52] This is desirable in that if the child or obstruction is lifted away from the drain port of the pool, the pump may regain its prime quickly, causing the sealing element 36 to close quite rapidly. Of course, this can cause the obstruction to be sucked back onto the drain port of the pool. If the one or more legs are configured so as to enter into a locking position, as illustrated in FIG. 8, then there will be sufficient time to remove the obstruction, such as a child, from the drain port of the pool. This will require the manual resetting of the sealing element 36. This can be accomplished by means of a pull chain 61 connected to an extension, such as through aperture 57, of the sealing element 36. In this manner, the pool owner can easily and conveniently pull the sealing element 36 back into a closed position, such that the pump regains its prime and functions under normal conditions after the obstruction has been removed. [Para 53] With reference again to FIGS. 1 7 and 1 8, a pump 1 60 is shown with a water intake 1 64 and a water outlet 1 62. Some pumps may include what is referred to as a "pot" 1 66. As illustrated in FIGS. 1 7 and 1 8, the system 10 of the present invention is typically directly connected to the pump 1 60, such as at the pot 1 66, water inlet 1 64, or more preferably at the winterizing drain plug aperture 1 68. An advantage of the safety valve system 1 0 of the present invention being placed at the winterizing drain port 1 68 is that the safety valve 1 0 serves as a discharge or drainage port for winterizing and the like, as well as a vacuum relief safety valve. Typically, drain plug 1 70 is threadedly received within the drain port 1 68, such that when the pump is not going to be used for prolonged periods of time, such as when cold weather is imminent, the drain plug 1 70 is removed such that the water within the pump 1 60 drains therefrom. In this case, the safety valve device 1 0 could be unthreaded and removed, causing the water within the pump to flow out of the pump. Alternatively, the safety device 10 could have the sealing element 36 pushed inwardly therein until it is locked into place, allowing the water to drain therefrom. However, it will be appreciated that the safety valve system 1 0 of the present invention can be attached to the pump 1 60 by other means, such as a hole drilled into the inlet port or in the pot, which may or may not be by threaded engagement. In such a case, the drain plug 1 70 would be inserted into the drain aperture 1 68 in normal fashion.

[Para 54] With reference again to FIGS. 9-1 5, in one embodiment, the present invention incorporates an electric switch assembly 70 having a depressable member 71 such that when the depressable member 71 is depressed, the switch is activated or changed from an open to a closed state such that electricity can flow through wires 72 to an electric circuit so as to shut off power to the pump. An illustrative embodiment is shown in the attached figures, wherein the sealing element 36 includes a projection or plunger 66 having an enlarged end forming one or more ledges 69. The depressable member 71 of switch 70 is positioned such that the plunger ledge 69 and the depressable member 71 are in alignment with one another. Normally, the sealing element 36, and thus the plunger 66, is biased upwardly or outwardly such that the ledge 69 and the depressable member 71 are not in contact with one another, as illustrated in FIG. 1 4. However, as will be more fully described herein, in an excessive vacuum situation when the sealing element 36 is moved into the inner chamber 32, the plunger 66 comes into contact with the depressable switch member 71 , as illustrated in FIG. 1 6. As illustrated in FIG. 1 6, when the sealing element 36 is moved inwardly into the housing, spring 48 is compressed and the air inlets 22 and 23 open such that air can flow therethrough, around sealing element 36, into flutes or internal channels 53, and through air outlet 30 and into the pump such that the pump loses its prime, as described above. Simultaneously, the plunger 66 is moved downwardly and into contact with the depressable member 71 of switch 70. Typically, switch 70 is secured to the housing via bolts 67 or the like. As will be more fully described herein, depression of the switch mover 71 provides power to an electric circuit which shuts off power to the pump.

[Para 55] To prevent the inadvertent depression of plunger 66, as well as to protect the electronic switch from the environment, a cover cap 60 is provided. The second shell includes structure to house the switch 70 and to accommodate the attachment of the cover cap 60, such as by insertion of a pin, screw, or the like through aperture 65. Wires 72 extend from the switch 70 to the electronic circuit, as will be more fully described herein. In a particularly preferred embodiment, the plunger 66 is threadedly attached to an extension of the sealing element 36, such as by means of jam nut 73. This enables the distance between the plunger, and particularly ledge 69 and the depressable member 71 of switch 70 to be adjusted as needed. This also enables the parts to be arranged and secured to one another in an orderly fashion when constructing the system 10, as the plunger, as illustrated, is disposed outside of the ambient air inlet apertures 22 and 23. [Para 56] Although a particularly preferred embodiment has been illustrated and described having a depressable switch member 71 , it will be understood by those skilled in the art that any type of electric, photoselective, wireless switch or the like wherein the inward movement of the sealing element 36 can activate the switch and shut off power to the pump as contemplated by the present invention. The important aspect of this embodiment is that the physical movement of the sealing element 36 results in activating an electric circuit such that the electric circuit at least temporarily shuts off power to, or otherwise disables, the pump. [Para 57] With reference now to FIG. 1 9, the safety valve system 10 incorporating the electric switch is shown attached to the drainage port 1 68 of the pump 1 60. In this case, the drainage port 1 68 is formed in a pot 1 66 having a removable lid, as is the case with certain pool pumps. Electric leads 72 extend to a control box 90 having a door 92. Leads 93 may extend directly to the pump 1 60 for automatically turning the pump on or off in a permanent manner which can then later be reset. However in a particularly preferred embodiment, the electric circuit includes a time relay 74, a transformer, a timer 78 and a switch 77, which is normally closed. Lead wire 79 from the electric circuit of the box 90 can then be used to power the pump. As will be more fully described herein, the electric circuit within the box 90 or the pump motor, serves to at least temporarily shut off power to the pump 1 60 when an excessive negative pressure within the pump or water circulation system is encountered.

[Para 58] With reference now to FIG. 20, an illustrative wiring diagram consisting of two electrical circuits, namely, a high voltage alternating current circuit 68 and a low voltage direct current circuit 76. The high voltage circuit 68 includes a normally closed switch 77, a time delay relay 78 and the pump 79. The low voltage circuit 76 includes a time delay relay 74, a low voltage direct current output transformer/power supply 75, switch 70 and relay 73. When switch assembly 70 is actuated from its biased open circuit position to a closed circuit position, or is otherwise actuated, relay 73 is energized, causing normally closed switch 77 to open and turn the pump off. In a particularly preferred embodiment, another time delay relay 78 is used to postpone the pump restart, such as a five minute delay, after an entrapment to allow for enough time to free the impediment while also automatically supplying power to the pump again so as to avoid the need to manually reset the system.

[Para 59] With reference now to FIG. 21 , the sequence of events is such that the pump is initially powered on 1 1 0. Time delay relay 78 is energized 1 26 causing the start up of pump 79 to be delayed for a predetermined time, typically five minutes. After the five minute delay 1 28, the pump will start on 1 30, and run on the normal filtration cycle using typical power supply such as 1 1 0 or 220 alternating current voltage or 3-phase power supply. After this delay, relay 74 is energized 1 1 2. This relay serves to delay the powering of transformer 75 for a predetermined time, such as five seconds 1 1 4. Thus, time delay relay 74 acts as a surge-ignoring device when the pump is initially powered on. It is not uncommon when pumps are powered on initially that a high vacuum level occurs. To prevent the electric circuit 76 from immediately shutting off the pump, relay 74 is energized and delays the providing of power to the rest of the circuit for at least several seconds. The pump starts and runs on the normal filtration cycle using the typical power supply, such as a 1 10 or 220 alternating current voltage or 3 PH power supply. [Para 60] After the five second delay, the transformer 75 is energized 1 1 6 as the 1 2 volts to 28 volts of direct current is output to transformer 75. The pump remains on until there is an entrapment 1 1 8, determined when the switch 70 is closed from its normally open position 1 20.

[Para 61 ] As described above, upon entrapment or blockage, the vacuum level inside the pump 79 is elevated creating a differential pressure across sealing element 36, allowing atmospheric air to push the sealing element 36 and compress spring 48 until the sealing element 36, and any associated O-rings, passes grooves 53 in the housing, allowing atmospheric air to rapidly fill the pot 84 resulting in the pump 79 losing its prime. Simultaneously, plunger 58 moves downwardly into contact with the switch depressable member 71 to close switch 70. Closing switch 70 results in opening switch 77 which is normally closed 1 22. This immediately shuts off power to the pump 1 24. This all occurs in a fraction of a second. Switches 70 and 77 automatically and momentarily return to their normally open and normally closed positions, respectively.

[Para 62] The sealing element 36 and plunger 58 will spring back momentarily to normal operating condition once the excessive negative pressure condition is alleviated, such as by removing the entrapment or blockage from the drainage system. In a particularly preferred embodiment, a time delay relay 78 is energized 1 26 resulting in a delay of a predetermined amount of time, such as five minutes 1 28, before the power to the pump is restored and the pump is powered on 1 30 again automatically. Of course, it will be appreciated by those skilled in the art that the pump could be required to be manually reset and powered on. However, it is believed that the delay and automatic powering of the pump is preferable. The five minute delay is used to postpone the pump restart immediately after an entrapment to allow for enough time to free the impediment. [Para 63] The present invention also serves as a surge suppressor. The surge suppressor function is achieved by venting off the sudden vacuum rise while the sealing element 36 is momentarily depressed. During surges, the valve 10 protects the pump filtration equipment against shocks and vibrations during pump start-ups resulting in reduced maintenance cost, less down time and longer equipment life. The electric circuit 76 also accounts for such surges by incorporating relay 74 so as to delay the supply of electricity to the remainder of the circuit for at least a few seconds, as described above, so that the pump is not automatically shut off within the first few seconds of operation when surges typically occur. The safety valve 10 itself will not open and vent the suction line to atmosphere unless the pump vacuum level is exceeded in the course of operation, such as an initial vacuum surge or body entrapment or the like. [Para 64] Although several embodiments have been described in detail for purposes of illustration, various modifications may be made without departing from the scope and spirit of the invention. Accordingly, the invention is not to be limited, except as by the appended claims.