This application claims priority from U.S. Provisional Patent Application Ser. No. 60/937,599 filed Jun. 27, 2007, and incorporated herein in its entirety by reference.
FIELD OF THE INVENTIONThe disclosed device relates to fluid activated switches for electrical devices. More particularly, the disclosed device relates to a switch for a sump pump having a hose mount that imparts a ground reference to the water or fluid while concurrently insuring the user self-installs the device at a proper level in the water to ensure proper operation.
BACKGROUND OF THE INVENTIONSump pumps are commonly employed on boats and ships to ensure that the bilge tanks do not overflow and are promptly and automatically emptied when needed. Another common function of a sump pump is to protect a basement from flooding.
In such installations, the pump is conventionally activated when water or other fluid reaches a certain level in the sump tank or bilge. Once activated by a switch the pump pumps out the excess water or fluid in the tank.
Many switches have been employed over the many years of sump pumps. One type of switch is a float switch is the part of the sump pump that activates the pump when water reaches a certain threshold. Essentially, a float on the end of a control rod rises and falls with water levels. At some lever in the rise, the switch activates the pump to remove fluid. Once the float switch settles to a new level as water is evacuated, it will turn off the pump. Due to harsh operating conditions, especially in a marine environment, a float switch is usually the first part of a sump pump to break, so it is recommended to choose a sump pump whose float switch is easily replaceable.
Another type of pump switch is the diaphragm switch which is engaged to the body of the pump which is immersed under water. A membrane in the diaphragm switch is sensitive to water pressure. As the water level rises, the water pressure increases and the diaphragm becomes concave, thereby activating the switch to turn on the sump pump. When the water level drops, the switch turns off. Such switches in a marine environment with oil and debris in the water are subject to problems and mechanical failure. Further the rocking of a boat can cause the water in the tank to push on the diaphragm and activate the pump in a condition that is too low for the pump to operate.
In the highly dynamic application such as the bilge of a small boat, as the boat bounces from wave to wave, a pivoting float will cause the switch to close many times per minute even without water in the bilge. This needlessly consumes the switch contact so that the system has a relatively short life. Further, a diaphragm switch can suffer the same fate due to moving fluid in the bilge from the moving and rocking boat.
A more modern switch employs electronic switching using sensors to ascertain the presence of water or fluid sufficient to require pump activation. Generally, such electronic devices employ a plurality of electrical contacts with the fluid with one to impart an electrical signal or other aspect to the fluid which is picked up by the other sensor. Or, the second sensor may negate the signal imparted if fluid is present and fail to do so when it is not. Many such devices use some type of electronic sensing that employs a reference to battery ground to the signal received to ascertain the presence of water and turn on the pump. The sensor continually sensing the fluid for an electronic property such as voltage, current, inductance impedance, resistance, or one or a combination of such electronic properties, will generally be under the fluid when activating the pump, and will turn the pump off if not under the fluid. The monitoring sensor is seeking the electronic property imparted to the fluid by a second component which must always be below fluid level for the device to work. It is extremely important that the plurality of electronic contacts for such devices to be properly immersed in the fluid to be pumped. If one of the electronic contacts is mounted too high and out of the fluid, the electronic switch cannot function to turn on the pump since no signal is transmitted or received to cause it.
However, since most such pump switches are user-installed, and because users fail to read directions, or view the electronic contacts and assume the wrong mounting scheme, many electronic switches for sump pumps fail or perform poorly.
As such, there exists an unmet need for a sump pump switch which will endure the harsh marine environment and moving fluid in a bilge or other tank, to properly activate a sump pump. Such a device should employ electronic communicating contacts with the fluid which provide and receive a signal through the fluid which ascertains the presence or absence of the fluid. Such a device should impart a ground reference to the fluid such that it can be accurately measured should the bilge be poorly grounded. Finally, and of major importance, such a device, being generally user-replaced, should provide a mounting configuration which ensures that the sensor is properly submersed in the fluid it monitors and thereby avoids confusion or assumption by the user as to proper mounting.
SUMMARY OF THE INVENTIONThe disclosed device is a float switch replacement for a marine bilge sump pump or other sump pump which is immersed in a fluid such as water in a storage tank such as a bilge or sump tank.
The device employs an electronic circuit to constantly sample the fluid for an electronic property using a first sensor that communicates through the casing with the fluid. A second contact is employed to affect the electronic property by proving a ground to the fluid such that the electronic property can ascertain the presence of fluid and turn on the pump.
In the current device, the electric property is a capacitance load of the bilge water that is monitored. An analog inverter CMOS chip oscillates at approximately 10,000 hertz. A frequency is generated into the fluid which is referenced at the water sensor. Through the sensor, a logic circuit looks for a change in frequency to activate the pump. Water covering a metallic component will change the frequency sufficiently to flip the logic circuit to turn on power to the pump, however ungrounded tanks such as fiberglass tanks or those on fiberglass boats, and improperly mounted sensor components communicating with the fluid, will cause the switch to malfunction. A ground communicating with the battery providing power to the logic circuit, submersed in the fluid, enhances the performance of the logic circuit by providing a better reference to ground through the fluid.
This problem with improperly mounted sensors and poor ground reference has been exacerbated in prior manufactured devices which have employed a casing wherein the two or more metal electronic monitor components communicating through the casing, have to be properly oriented in the fluid. Users installing such devices frequently do not read the directions and install them incorrectly. Most such devices employ screw apertures to mount the device in the tank and invite improper installation by installers who assume one or both metal components must be below water level.
Most sump pumps employ a fluid intake under a bottom or very low side surface for intake of fluid. A pump inside the pump casing exhausts fluid through an exhaust hose which is routed to drain the bilge or tank. The hose is conventionally engaged to a hose bib on the pump with a hose clamp. This hose clamp and bib are conventionally located just above the intake by design since the intake is conventionally located as low as possible in the tank in which the pump is placed.
The novel casing provided with the device employs two components which enhance performance of the internal electronic switch. First, since the hose bib on sump pumps is conventionally located above the lower water intake which is the lowest point the water will reach, providing a mounting member that extends from the casing to mount the device to the hose bib, inherently mounts the casing, and sensing and monitoring component, just above the lowest point the water can reach. This is exactly the correct placement for the sensor and by providing a mounting member with a curved lower surface, adapted to engage under the hose clamp, the user inherently will mount the casing correctly even if they fail to read the installation directions which is a frequent occurrence.
Additionally, the mounting member is connected to the battery ground. By mounting it to the mounting member which will encounter the fluid, a very good ground reference is imparted to the fluid before or at the same time the fluid reaches the sensing component looking for an electronic property in the fluid to ascertain fluid levels at or above the sensing component to activate the switch to turn on the pump. On fiberglass boats and tanks, this properly located reference to ground greatly enhances switch performance. On older boats corroded tanks, an equal gain in performance is provided by this novel inherently properly positioned grounding component.
It is thus an object of this invention to provide a switch for a sump pump which has a member extending from the casing which provides a curved surface to engage under a hose clamp conventionally employed on hoses engaged to a submerged sump pump.
It is a further object of this invention to provide such a sump pump switch with the hose clamp mount adapted member which will inherently cause users to properly situate the device in the fluid to properly sense fluid level.
It is yet another object of this invention to provide a casing to house electronic sensing components which will properly situate broadcasting and receiving electronic elements in the fluid by simply engaging the casing to a hose bib under a hose claim on the pump being switched.
With respect to the above description and background, before explaining at least one preferred embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangement of the components and/or steps set forth in the following description or illustrated in the drawings. The various apparatus and methods of the invention herein described and disclosed are capable of other embodiments and of being practiced and carried out in various ways which will be obvious to those skilled in the art once they review this disclosure. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for designing of other devices, methods and systems for carrying out the several purposes of the present disclosed device a sump pump switch and casing therefor which is adapted with mounting members which inherently place the device properly in the fluid for its sensors to operate. It is important, therefore, that the objects and claims be regarded as including such equivalent construction and methodology, insofar as they do not depart from the spirit and scope of the present invention.
BRIEF DESCRIPTION OF DRAWINGSFIG. 1 depicts front perspective cut view of the disclosed sump pump switch and the switch housing having an extending grounded mounting member which is curved and adapted for engagement under a hose clamp on the hose bib of a sump pump.
FIG. 1ashows the device ofFIG. 1 engaged to the house and hose bib and the fluid level engaging the sensor.
FIG. 2 shows a conventional sump pump and the hose bib upon which the mounting member is engaged under a hose clamp holding a fluid exhaust hose to the pump.
FIG. 3 depicts typical prior art wherein two sensors or electronic contacts are provided and must be carefully mounted to assure proper positioning in the fluid.
FIG. 4 shows a block diagram of the electronic components electronically engaged to energize or de-energize the pump.
FIG. 5 depicts a block diagram of an enhanced version of the device showing a plurality of sensors for ascertaining fluid level and energizing the pump.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTSReferring now to the drawings inFIGS. 1-5,FIG. 1 shows a perspective view of the disclosed sumppump switch device10 having ahousing12 having and extending groundedmetal mounting member14 which has a curve about its center axis orcurved edge16 portion. The electronic components for the impedance sensing device are engaged inside thehousing12 in a fashion that seals them from fluid in the tank. Wires (not shown) communicate to the circuit inside thehousing12 to provide electric energy to the circuit.
The mountingmember14 is connected inside thehousing12 to the ground wire or circuit providing electric power to thedevice10 thereby providing the mounting member14 a direct electrical link to the ground of the electrical system or battery. The curved shape of the mountingmember14 provides it with a means for cooperative surface engagement with the curved surface of a sumppump exhaust hose17 which is engaged over ahose bib18 and secured with a hose clamp on thehose bib18 of asump pump20. However, those skilled in the art will realize that other shapes may provide such an engagement for instance having a planar shape to the mountingmember14 and having a width narrower than the diameter of thehose17.
Conventionally, as depicted inFIG. 2, most such sump pumps20 employ afluid intake22 under a bottom or very low side surface of thepump20 for intake of the water or fluid from a tank or other water collection container in which they are mounted. An electric pump inside thepump casing23 exhausts fluid through an exhaust hose17 (FIG. 1) from thehose bib18 just above thefluid intake22. It is important to keep thepump20 primed with fluid for proper operation and protection of the blades or rotors or other pump components. Consequently, leaving sufficient water or fluid in the bottom of the tank to maintain thepump20 primed, at awater level15 at least above theintake22 and preferably somewhere between thehose bib18 and thesurface bottom21 of the tank in which thepump20 sits, is important to its operation and longevity.
Thedevice10 features anovel casing12 and mountingmember14 which serves to automatically position thedevice10 to achieve apreferred fluid level15 above the bottom21 of the tank to ensure protection of thepump20 from running dry and proper operation. Thedevice10 in this mounted position shown inFIG. 1a, is engaged electronically with the electrical power providing energy to operate thepump20 and to turn thepump20 on and off when electronic properties in the fluid are sensed by asensor13. Once the level of fluid goes below the top edge of thesensor13 when thedevice10 engaged in the mounted position to thehose bib18, the power is interrupted by thedevice10 to thepump20 thereby turning off thepump20.
The mountingmember14 which extends from thecasing12 to engage under thehose clamp19 on thehose bib18, allows users to simply mount thedevice10 on thebib18 andhose17 and know it is correctly placed. Further, because of the potential that the tank in which the device is mounted will be ungrounded or have a poor ground, in a particularly preferred mode of thedevice10, themember14 is engaged to battery ground to give a better ground reference to the circuit monitoring the fluid impedance. Themember14 when in contact with the fluid in the tank, thus communicates a ground reference to the fluid. This communication of the ground reference is enhanced by the engagement of themetal hose clamp19 to themember14 by increasing contact area with the fluid.
FIG. 2 shows aconventional sump pump20 and thehose bib18 under which the mounting member is engaged under ahose clamp19 as inFIG. 1. As can be seen, most such pumps position thehose bib18 for the hose carrying fluid from the tank, above theintake22.
Shown inFIG. 3 is thetypical sump pump20switch23 employed in many fluid collection tanks. This type of switch employs twosensors24 which both must be positioned within the fluid and therefor must be carefully mounted to assure proper positioning in the fluid. Such conventional sensors are generally engaged to the tank surface or simply placed inside the tank itself. Frequently, users make the mistake of leaving one of thesensors24 out of the fluid on the mistaken assumption that fluid contacting bothsensors24 activates the pump.
FIG. 4 shows a preferred mode of a switching orlogic circuit30 employed herein and engaged inside thehousing12. Thecircuit30 receives power from the battery or other power system of the boat or other location where thedevice10 is employed. Themember14 is engaged to the ground from the power supply and as noted communicates a ground reference to the fluid in the tank. Thesensor13 communicating with the fluid in the tank continuously provides thelogic circuit30 with an impedance reading for the fluid or water which has the ground reference being communicated from themetallic member14. When thelogic circuit30 discerns from thesensor13, that impedance has changed from a preset point, because thefluid level15 covers all, or more, or less, surface area of thesensor13, it will cause a switching of electrical energy from the power supply to energize theload32 which in this case is thepump20 to be initiated.
However, because boats frequently encounter swells and other motions which causefluid level15 to change drastically as it sloshes in the tank, thereby altering the fluid impedance reading, a delay on35 will initially prevent switching on of thepump20 for a time duration. The same problem of sloshing fluid can also causefluid levels15 in the tank to temporarily fall to a point where thesensor13 detects the fluid impedance to have fallen outside the range to switch on thepump20. In this instance, in the preferred mode of thedevice10, a delay off37 is initiated to maintain thepump20 energized for a time delay wherein thedevice10 takes additional readings of fluid impedance from thesensor13 before switching of the power to thepump20.
As can be discerned, by providing a ground communication to themetallic member14, and providing a shape to themember14 adapting it to engage on the hose and hose bib of the output hose, thesensor13 of thedevice10 is always properly positioned to measure if thefluid level15 covers the sensor entirely, partially, or not at all, which will vary the fluid impedance levels communicated to thecircuit30 allowing onboard software to discern whether energizing or de-energizing thepump20 is in order. The time delays for either option, while not required for thedevice10 to operate substantially better than conventional switches, are preferred to allow for the uncertainty ofwater level15 movement due to tank movement caused by the boat traveling, turning, or encountering rough water.
Further, while fluid impedance is the current preferred electrical property measured by thecircuit30 through communication with thesensor13, and the enhancement of such measurement is provided by the communication of a ground reference to the fluid, those skilled in the art will no doubt realize, upon reading this disclosure, that other electrical properties might be communicated to the fluid by themember14 and then measured by thecircuit30 in contact with thesensor13 to ascertain thefluid level15 in the tank. As such, any electrical property that might be communicated to the fluid level through themember14 and measured by thelogic circuit30 to energize and de-energize thepump20 based onfluid levels15 discerned as would occur to those skilled in the art is anticipated to be within the scope of this disclosure.
Employing thelogic circuit30 and the enhanced ground reference to the fluid, thedevice10 may also be combined with other sensors offluid level15 or system operation as another means to operate thepump20 only as required byfluid levels15. In this mode of thedevice10 thelogic circuit30 having onboard software adapted to the task, would continuously monitor a plurality of sensors of system performance andfluid level15.
Thewater sensor13 would continue to provide fluid impedance levels. Additionally monitored can be afloat switch36 which would operate to close upon thefluid level15 reaching a defined level. Amotor load sensor38 which would monitor the amount of power being drawn by thepump20 since less power is drawn when no fluid is being drawn through thepump20. An air pressure monitor39 would monitor the air pressure inside the tank holding thepump20 anddevice10 as such pressure can vary depending on thefluid level15 in the tank.
The logic circuit in this mode of thedevice10 would require one or a plurality of inputs to signal that thefluid level15 was sufficient to energize thepump20 or insufficient and de-energize thepump20. The delay off37 and delay on35 would operate probably with a shorter time duration since a plurality of sensors offluid level15 would be communicating to thelogic circuit30 thefluid level15. This mode of thedevice10 provides a great enhancement tosump pump20 monitoring and protection by continuously monitoring a plurality of indicators offluid level15 which serves to avoid errors by thelogic circuit30 in accidental activation or deactivation of thepump20.
Finally, it is to be understood that elements of different construction and configuration and different steps and process procedures and other arrangements thereof, other than those illustrated and described, may be employed for a sump pump switch with hose mounting member within the spirit of this invention.
As such, while the present invention has been described herein with reference to particular embodiments thereof, a latitude of modifications, various changes and substitutions are intended in the foregoing disclosure, and it will be appreciated that in some instance some features of the invention could be employed without a corresponding use of other features without departing from the scope of the invention as set forth in the following claims. All such changes, alternations and modifications as would occur to those skilled in the art are considered to be within the scope of this invention as broadly defined in the appended claims.