Floor condition sensor

Information

  • Patent Grant
  • 6208262
  • Patent Number
    6,208,262
  • Date Filed
    Tuesday, June 1, 1999
    25 years ago
  • Date Issued
    Tuesday, March 27, 2001
    23 years ago
Abstract
A floor sensor assembly includes a receptacle having at least one first electrical contact and a first substantially flat surface partially defining a floor surface. A sensor device is detachably secured to the receptacle and includes at least one second electrical contact electrically connected to the at least one first electrical contact of the receptacle. At least one of a temperature sensor and a moisture sensor is electrically connected to the at least one second electrical contact. The sensor device also includes a second substantially flat surface partially defining the floor surface. At least one electrical conductor is electrically connected to the at least one first electrical contact of the receptacle.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to sensor devices and, more particularly, to sensor devices for detecting moisture and/or temperature.




2. Description of the Related Art




Sensor devices are used to sense temperature and the presence of moisture in an ambient environment. Such sensors can be elevated above ground level in order to detect temperature and precipitation, in liquid or frozen form, in an outside ambient environment. However, it would be difficult to use such sensors to detect temperature and the presence of moisture on a floor surface, which would require the sensors to be embedded directly in the floor surface. The sensors could easily become damaged and malfunction when subjected to the forces that are typically exerted on a floor surface. Should such damage or malfunction occur in an embedded sensor, the entire sensor assembly would need to be extracted from the floor, since each sensor assembly is formed as single, self-contained unit. The reinstallation of a new sensor assembly would require that the surrounding floor surface be repaired, which may include grouting or concrete work. Further, the wiring leading to the sensor assembly, which would also need to be embedded under the floor surface, may also need to be removed and replaced, thereby requiring more work on the surrounding flooring.




Another problem is that a sensor assembly may not have a flat surface which may be mounted at the same level as an existing floor. The sensor assembly also may not have a thickness which allows the sensor assembly to be mounted at the same level as the existing floor. In either case, the sensor assembly would present a depression or projection when mounted in the floor, thereby creating a tripping hazard for nearby pedestrians.




Yet another problem is that known sensor assemblies do not have a size and shape which fits in well between the surrounding tiles of a floor. Thus, gaps in the flooring would be created between the sensor assembly and the surrounding tiles, and such gaps would be problematic to fill in.




SUMMARY OF THE INVENTION




The present invention provides a tile-shaped floor sensor assembly including a receptacle which is permanently installed in a tile floor. The receptacle has a central cavity for receiving a sensor device which can be easily removed and replaced if it becomes damaged or defective.




The invention comprises, in one form thereof, a floor sensor assembly including a receptacle having at least one first electrical contact and a first substantially flat surface partially defining a floor surface. A sensor device is detachably secured to the receptacle and includes at least one second electrical contact electrically connected to the at least one first electrical contact of the receptacle. At least one of a temperature sensor and a moisture sensor is electrically connected to the at least one second electrical contact. The sensor device also includes a second substantially flat surface partially defining the floor surface. At least one electrical conductor is electrically connected to the at least one first electrical contact of the receptacle.




An advantage of the present invention is that the floor sensor assembly can be mounted in a floor, and, if the sensor device should become damaged or defective, it can be easily removed and replaced without disturbing the existing flooring.




Another advantage is that the floor sensor assembly has the size and shape of a tile and can therefore be easily incorporated into a tile floor without creating a safety hazard.











BRIEF DESCRIPTION OF THE DRAWINGS




The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, wherein:





FIG. 1

is a top, perspective, partially exploded view of one embodiment of a floor sensor assembly of the present invention;





FIG. 2

is a bottom, perspective, partially exploded view of the floor sensor assembly of

FIG. 1

;





FIG. 3

is a side, sectional view of the floor sensor assembly of

FIG. 1

;





FIG. 4

is a partial, side, sectional, exploded view of the floor sensor assembly of

FIG. 1

; and





FIG. 5

is a schematic diagram of the floor sensor assembly of FIG.


1


.











Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrates one preferred embodiment of the invention, in one form, and such exemplification is not to be construed as limiting the scope of the invention in any manner.




DETAILED DESCRIPTION OF THE INVENTION




Referring now to the drawings, and particularly to

FIG. 1

, there is shown a floor sensor assembly


10


including a receptacle


12


, a sensor device


14


and an electrical cable


16


.




Receptacle


12


is substantially square-shaped, with each side


18


having a length


20


of approximately between four and eight inches, and preferably approximately six inches. Receptacle


12


has a thickness


22


of approximately between 0.25 inch and 0.5 inch, and preferably approximately 0.375 inch. Thus, receptacle


12


has approximately the same size and shape as a conventional floor tile. A substantially flat top surface


24


of receptacle


12


is substantially flush or coplanar with a surface


26


of a surrounding floor


28


, as best seen in

FIGS. 3 and 4

. Top surface


24


includes a cavity


30


for receiving sensor device


14


. Cavity


30


includes four screw holes


32


which allow sensor device


14


to be detachably secured or removably attached to receptacle


12


with four respective screws


34


. Cavity


30


also includes three exposed electrical contacts


36


,


38


and


40


which are electrically connected to cable


16


through an opening


42


in a bottom surface or underside


44


(

FIG. 2

) of receptacle


12


. Contacts


36


,


38


and


40


are disposed on a printed wiring board


45


embedded in receptacle


12


. Opening


42


can be filled with epoxy (not shown) in order to secure cable


16


in place within opening


42


.




Mortar/concrete tension grooves


46


enable receptacle


12


to better adhere to the grout, mortar or concrete in the floor


28


in which receptacle


12


is mounted. A channel


48


receives cable


16


, thereby protecting cable


16


from damage that might otherwise result from bearing the weight of receptacle


12


and from partially absorbing any forces that may be exerted on top surface


24


of receptacle


12


. A widened portion


50


of channel


48


includes two threaded screw holes


52


which each receive a threaded shaft


54


of a respective screw


56


. Respective nylon heads


58


of screws


56


can be rotated until heads


58


clamp cable


16


against channel


48


. Heads


58


can be provided with widths such that heads


58


almost touch each other, which would spread the clamping force exerted by heads


58


over a maximum surface area of cable


16


. In this way, screws


56


provide strain relief, which prevents cable


16


from being pulled out of receptacle


12


by a force in the direction of arrow


60


.




Cable


16


includes four electrical conductors


62


,


64


,


66


and


68


, with conductors


64


and


66


being grounded. A jacket


70


, formed of polyvinyl chloride or another type of plastic, surrounds and protects conductors


62


,


64


,


66


and


68


. At a distal end of cable


16


, conductors


62


,


64


,


66


and


68


are connected to a modular jack


72


in the form of an RJ-45 connector. Through connector


72


, an electrical controller (not shown) measures the electrical characteristics of sensor device


14


and, based upon these electrical characteristics, controls a resistive heater (not shown) embedded in floor


28


.




Sensor device


14


includes a moisture sensor


74


in the form of an inner brass ring


76


and an outer brass ring


78


separated by a layer of epoxy


80


. As best seen in

FIG. 3

, outer brass ring


78


forms a housing for sensor device


14


. Along with a central epoxy core


82


, rings


76


,


78


and layer


80


provide sensor device


14


with a substantially flat top surface


84


. Top surface


84


is substantially flush or coplanar with top surface


24


of receptacle


12


and with the remainder of surface


26


of floor


28


when sensor device


14


is attached to receptacle


12


. Thus, each of top surfaces


24


and


84


partially defines surface


26


of floor


28


. The electrical resistance of epoxy layer


80


varies with the level of moisture present on top surface


84


. More particularly, the resistance of epoxy layer


80


decreases with an increasing level of moisture on top surface


84


.




A temperature sensor


86


(

FIG. 5

) is in the form of a temperature-sensing resistor which is disposed on a printed wiring board


88


. The electrical resistance of resistor


86


increases with temperature. Wiring board


88


also includes a ground wire


90


and a resistor


92


which electrically connect sensor housing


78


with ground. Resistor


92


prevents potentially destructive currents from flowing in ground wire


90


. Potential sources for the destructive ground current include the magnetic field of other nearby current-carrying conductors and operating electric motors.




A bottom surface


94


of wiring board


88


includes three exposed electrical contacts


96


,


98


and


100


, with contact


98


being connected to ground through grounded contact


38


on receptacle


12


. One of contacts


96


and


100


is connected to temperature-sensing resistor


86


, while the other one of contacts


96


and


100


is connected to inner ring


76


of moisture sensor


74


. Three conical springs


102


provide a self-aligning electrical interconnection between respective contacts


96


,


98


and


100


on sensor device


14


and contacts


36


,


38


and


40


on receptacle


12


. Springs


102


are shown as being attached to contact pads


96


,


98


and


100


. However, it is also possible for springs


102


to be attached to contacts


36


,


38


and


40


, or to not be attached to any of contacts


36


,


38


,


40


,


96


,


98


and


100


.




Sensor device


14


includes four through holes


104


through which sensor device


14


can be removably attached to receptacle


12


with screws


34


. Screw holes


32


of receptacle


12


and through holes


104


are nonsymmetrically positioned or unevenly spaced to thereby provide a keying arrangement which allows sensor device


14


to be secured to receptacle


12


in only one desired rotational orientation. That is, all four through holes


104


simultaneously align with respective screw holes


32


in only one rotational position along the 360° arc of possible rotational positions.




During use, sensor device


14


is subject to being damaged from the forceful impacts to which floor surfaces are typically occasionally exposed. If sensor device


14


should become damaged or defective, due to impacts or another reason, the present invention allows sensor device


14


to be removed and replaced quite easily. More particularly, after screws


34


are removed, springs


102


push sensor device


14


upward so that it can be easily lifted out of cavity


30


. A replacement sensor device


14


is then inserted into cavity


30


and screws


34


are screwed into screw holes


32


through through holes


104


. In replacing sensor device


14


, there is no need to remove receptacle


12


from floor


28


. Thus, the flooring surrounding receptacle


12


is not disturbed and there is no need to repair the flooring with grout, mortar or concrete work.




While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.



Claims
  • 1. A floor sensor assembly comprising:at least one electrical conductor; and a receptacle including: at least one first electrical contact electrically connected to said at least one electrical conductor; and a first substantially flat surface configured for partially defining a floor surface; a sensor device detachably secured to said receptacle said sensor device including: at least one second electrical contact electrically connected to said at least one first electrical contact of said receptacle; at least one of a temperature sensor and a moisture sensor electrically connected to said at least one second electrical contact; a second substantially flat surface configured for partially defining the floor surface; and an underside having a channel configured for receiving said at least one electrical conductor; said channel including at least one threaded screw hole and at least one screw having a shaft and a head, said shaft of each said screw being received in a respective said screw hole, said head of said at least one screw clamping said at least one electrical conductor against said channel.
  • 2. The floor sensor assembly of claim 1, wherein said underside of said receptacle has a plurality of tension grooves.
  • 3. The floor sensor assembly of claim 1, wherein said at least one electrical conductor includes a first end and a second end, said first end being electrically connected to said at least one first electrical contact of said receptacle, said second end being electrically connected to a modular jack.
  • 4. The floor sensor assembly of claim 1, further comprising at least one spring electrically interconnecting said at least one first electrical contact of said receptacle and said at least one second electrical contact of said sensor device.
  • 5. The floor sensor assembly of claim 4, wherein each said spring is attached to one of a first electrical contact and a second electrical contact.
  • 6. The floor sensor assembly of claim 1, wherein said receptacle includes a cavity, said sensor device being received in said cavity.
  • 7. The floor sensor assembly of claim 1, wherein said at least one electrical conductor includes a grounded conductor, said sensor device including a housing and a resistor electrically interconnecting said housing and said grounded conductor.
  • 8. A floor sensor assembly, comprising:a receptacle including: at least one first electrical contact; and a first substantially flat surface configured for partially defining a floor surface; a sensor device detachably and removably secured to said receptacle, said sensor device including: at least one second electrical contact electrically connected to said at least one first electrical contact of said receptacle; a second substantially flat surface configured for partially defining the floor surface; and at least one of a temperature sensor and a moisture sensor electrically connected to said at least one second electrical contact, said at least one of a temperature sensor and a moisture sensor including a moisture sensor having a layer of epoxy disposed between two electrically conductive elements, said layer of epoxy at least partially defining said second substantially flat surface of said sensor device; and at least one electrical conductor electrically connected to said at least one first electrical contact of said receptacle.
  • 9. The floor sensor assembly of claim 8, wherein said receptacle includes an underside having a channel configured for receiving said at least one electrical conductor.
  • 10. The floor sensor assembly of claim 8, wherein said receptacle includes at least one screw hole and said sensor device includes at least one through hole, each said through hole of said sensor device being aligned with a respective said screw hole of said receptacle.
  • 11. The floor sensor assembly of claim 10, wherein said at least one screw hole includes a plurality of screws holes, said screw holes being nonsymmetrically disposed such that said sensor device can be screwed to said receptacle in only one orientation.
  • 12. The floor sensor assembly of claim 8, wherein said floor sensor assembly has a thickness of approximately between 0.25 inch and 0.5 inch.
  • 13. The floor sensor assembly of claim 8, wherein said layer of epoxy has an electrical resistance which varies with a level of moisture on said second substantially flat surface of said sensor device.
  • 14. The floor sensor assembly of claim 8, wherein said two electrically conductive elements comprise two concentric rings at least partially defining said second substantially flat surface of said sensor device.
  • 15. A method of sensing at least one of temperature of a floor and moisture on the floor, said method comprising the steps of:providing a receptacle having a first substantially flat surface with a cavity, at least one first electrical contact being exposed in said cavity; electrically connecting at least one electrical conductor to said at least one first electrical contact; mounting said receptacle and said at least one electrical conductor in the floor such that said first substantially flat surface is substantially coplanar with a surface of the floor; placing a sensor device in said cavity of said receptacle such that at least one second electrical contact of said sensor device is electrically connected to said at least one electrical contact of said receptacle, a second substantially flat surface of said sensor device being substantially coplanar with said first substantially flat surface of said receptacle; detachably securing said sensor device to said receptacle; removing said sensor device from said receptacle after said sensor device becomes at least one of damaged and defective; and installing a replacement sensor device in said cavity of said receptacle; wherein said receptacle remains mounted in the floor throughout said removing and installing steps.
  • 16. A floor sensor assembly comprising:at least one electrical conductor; a receptacle including: at least one first electrical contact electrically connected to said at least one electrical conductor; an underside having a channel and a clamping device, said channel being configured for receiving said at least one electrical conductor, said clamping device being configured for clamping said at least one electrical conductor against said channel; and a first substantially flat surface configured for partially defining a floor surface; and a sensor device detachably and removably secured to said receptacle, said sensor device including: at least one second electrical contact electrically connected to said at least one first electrical contact of said receptacle; at least one of a temperature sensor and a moisture sensor electrically connected to said at least one second electrical contact; and a second substantially flat surface configured for partially defining the floor surface.
  • 17. A floor sensor assembly, comprising:a receptacle including: at least one first electrical contact; and a first substantially flat surface configured for partially defining a floor surface; a sensor device detachably and removably secured to said receptacle, said sensor device including: at least one second electrical contact electrically connected to said at least one first electrical contact of said receptacle; a second substantially flat surface configured for partially defining the floor surface; and at least one of a temperature sensor and a moisture sensor electrically connected to said at least one second electrical contact, said at least one of a temperature sensor and a moisture sensor including a layer of epoxy at least partially defining said second substantially flat surface; and at least one electrical conductor electrically connected to said at least one first electrical contact of said receptacle.
  • 18. A method of sensing at least one of temperature of a floor and moisture on the floor, said method comprising the steps of:providing a receptacle having a first substantially flat surface with a cavity, at least one first electrical contact being exposed in said cavity; electrically connecting at least one electrical conductor to said at least one first electrical contact; mounting said receptacle and said at least one electrical conductor in the floor such that said first substantially flat surface is substantially coplanar with a surface of the floor; placing a sensor device in said cavity of said receptacle such that at least one second electrical contact of said sensor device is electrically connected to said at least one electrical contact of said receptacle, a second substantially flat surface of said sensor device being substantially coplanar with said first substantially flat surface of said receptacle; detachably and removably securing said sensor device to said receptacle; and removing said sensor device from said receptacle after said sensor device becomes at least one of damaged and defective, wherein said receptacle remains mounted in the floor throughout said removing step.
  • 19. The method of claim 18, comprising the further step of installing a replacement sensor device in said cavity of said receptacle.
US Referenced Citations (11)
Number Name Date Kind
3986110 Overall et al. Oct 1976
4135151 Rogers et al. Jan 1979
4679160 Whitener Jul 1987
4765187 Weinstein Aug 1988
4766369 Weinstein Aug 1988
4805070 Koontz et al. Feb 1989
4897597 Whitener Jan 1990
4935725 Turnau Jun 1990
5006969 Lai Apr 1991
5886256 DeAnna Mar 1999
5995003 Rogers Nov 1999