MXPA06005868A - Occupancy sensor assembly - Google Patents

Abstract

An occupancy sensor is provided with a housing having an interior cavity. A switch is mounted in the interior cavity of the housing and configured for placement in the open and closed positions. A fascia cover plate may be positioned on the housing to enclose the interior cavity. The fascia cover plate has a fascia rib on an interior surface thereof. The fascia rib is arranged to interfere with the switch in the disabled state to prevent positioning of the fascia cover plate on the housing.

Description

OCCUPATIONAL SENSOR UNIT Reference with Related Requests A related topic is described in the co-pending US patent application of Williams et al., Filed on the same date as the present one, under the heading "Occupancy sensor, double-circuit wall circuit breaker and method for its operation" - (Attorney's file 48513); and in the co-pending US patent application of R. Kart Bender et al., filed on the same date as the present one, under the title "Fascia plate of the occupancy sensor" (Attorney's file 48519); The entire content of both applications is expressly incorporated herein by reference.

FIELD OF THE INVENTION The present invention relates to an occupancy sensor unit. More particularly, the present invention describes an improved occupancy sensor unit that facilitates the maintenance of the sensor unit, enhances the efficiency of the ultrasonic sensors, and minimizes damage to the unit in heavy duty applications.

BACKGROUND An occupancy sensor is designed to detect the presence of one or more persons in a room, usually to determine whether or not to switch on several functions that use electricity in that room (for example lights, ventilation, and the like). This is particularly advantageous for institutions that have occupants who are not directly responsible for paying for the electricity they consume, since many times these people do not take care of turning off functions that use electricity, such as lights, ventilation and the like when they leave the room. room. Therefore, occupancy sensors can save a lot of energy. This has led several companies to buy them voluntarily; It has also resulted in the creation of laws in some states mandating the use of occupancy sensors in large areas as a measure of environmental conservation.

The two types of occupancy sensors that are most commonly used with circuit breakers or automatic wall switches, individually or in combination with one another, are passive infrared devices and ultrasonic devices.

In general, a passive infrared sensor ("PIR") will turn on the function when it detects a movement or a source of apparent heat. The technology of passive infrared occupancy detection allows the continuous detection of moving objects that emit infrared energy. This method of occupancy detection is also very sensitive even when it is based on the passive detection of sources of infrared energy movement.

An active ultrasonic sensor emits vibrations at frequencies of 25kHz or more and listens to the return echoes; if it detects an important Doppler shift that indicates the presence of a moving body, then turn on the function. The detector may turn off the function after a certain period without feeling movement, usually 3 to sixty minutes, as determined by the user. The sensitivity to movement of the device can usually be established by the user.

More specifically, the technology for occupancy detection with active ultrasonic Doppler acoustics allows the continuous detection of objects in motion that reflect ultrasonic acoustic energy. For example, currently available light switches or the like that are used in offices, emit an ultrasonic wave inside a room and detect the movement of people feeling a Doppler shift in the reflected ultrasonic wave. The Doppler shift in the reflected wave is caused by people moving within the room. This method of occupancy detection is very sensitive because it is based on an active source of ultrasonic acoustic energy. An apparatus and method of this type are described in U.S. Patent No. 5,640,143 to Myron et al (assigned to the same beneficiary of the present invention), the disclosure of which is hereby incorporated by reference in its entirety.

Each of these types of sensors has its disadvantages. For example, the PIR sensor requires a lens. The lens has an exposed front wall that allows the transmission of infrared energy to detect occupancy. The front wall is usually arranged very close to the manual control transfer switches. Consequently, in heavy duty applications such as in schools and offices, the lens is continually depressed in attempts to activate the manual command transfer switch. For example, often the lens is damaged due to acts of vandalism. Thus, the structural integrity of the lens is compromised very often and requires replacement.

Ultrasonic sensors use transducers to emit and receive sonic energy. Normally, to minimize the size of the device, the transducers are mounted directly on the circuit board. The transducers are arranged perpendicular to the circuit board and define an axis. The transducers send and receive a sensitivity pattern. The sensitivity pattern is strongest in the axis of the transducers. The sensitivity pattern is weaker as it moves away from the transducer axis. Therefore, the resulting composite sensitivity pattern of the transducers that send and those that receive is considerably higher along the transducer axis, but considerably smaller at the ends. This is undesirable, since the sensor pattern must have uniform sensitivity to the sides of the transducer shaft to effectively cover the entire controlled space.

To protect the ultrasonic transducers, a grid is usually placed in front of the transducers. The grid is commonly designated with openings to allow adequate passage of acoustic energy through the grid. When the connected lighting function is in service, the power must be disconnected from the function. The preferred way to disconnect power is to interrupt the circuit at the breaker; however, electricians often use a manual wall switch to disconnect power from the circuit. Subsequently, a wall switch of the occupancy sensor, automatic, can re-energize or activate the function, thus presenting a problem. Consequently, regulating bodies often require a switch in the occupancy sensor to prevent the sensor from activating the function. This is usually referred to as an "air space" switch that indicates that it is composed of metallic contacts separated by air.

The air gap switch in an occupancy sensor is normally hidden and for its access it is required that the switch closure plate be removed. After full service in the lighting function, an electrician must close the air gap switch, but this step is often forgotten. Therefore, reassemble the switch closing plate with the air gap switch in the open position. This requires a return on the switch and then the disassembly and assembly of the closing plate to close the switch. In this way valuable time is lost. Accordingly, in order to address these disadvantages, there have been several additional attempts to provide improved occupancy sensors. Examples of such occupancy sensors are described in U.S. Patent Nos. 6,798,341, to Eckel et al .; 6,587,049 for Thacker; 6,480,103 for McCarthy et al .; 6,222,191 for Myron et al .; 6,150,943 for Lehman et al .; 6,082,984 for Batko et al .; 6,049,281 for Oster eil; 5,973,594 for Bald in; 5,861,806 to Vories et al .; 5,703,368 to Tomooka et al .; 5,394,035 for Elwell; 5,392,631 for Elwell; 5,363,688 for Elwell; 5,319,283 for Elwell; 5,293,097 for Elwell; 5,281,961 for Ell; 5,142,199 for Elwell; 4,841,285 for Laut; 4,751,399 for Koehribg et al .; 4,703,171 for Kahl; 4,678,985 for Moski; 4,418,337 for Bader; 4,057,794 for Grossfield; and 2,096,839 for Barlow. Although, some of the characteristics of those occupancy sensor units lessen the disadvantages described above, so there is a continuous need for an improved occupancy sensor unit that facilitates the maintenance of the sensor unit, enhances the efficiency of an ultrasonic sensor, and Minimize damage to the unit in heavy duty applications.

SUMMARY OF THE INVENTION An object of the present invention is to solve at least the aforementioned problems and / or disadvantages, and to provide at least the advantages described below.

Accordingly, an object of the present invention is to provide a fascia closure plate that enhances ultrasonic transmissions and reduces damage due to tampering such as acts of vandalism.

Another object of the present invention is to provide a lens with improved durability without compromising its operation.

A further object of the present invention is to avoid leaving a switch of the unit in an undesired state after performing service or maintenance operations.

The aforementioned objects are achieved by providing an occupancy sensor with a housing having an interior cavity; a switch configured for positioning in the open and closed positions, and the switch installed in the interior cavity of the housing; and a fascia closure plate configured to be placed in the housing to close the interior cavity, the fascia has a fascia flange on the interior surface, the fascia flange arranged to interfere with the switch in the open condition to prevent the placement of the closure plate of the fascia on the housing when the switch is in the disabled state.

The above objectives are also achieved by providing an occupancy sensor to detect the occupation of a controlled space, containing at least one ultrasonic transducer, and a fascia closure plate to cover the transducer, the closure plate of the fascia has a grid arranged to allow the transmission of ultrasonic energy between the ultrasonic transducer and the controlled space, wherein at least one ultrasonic transducer is positioned near the grid to enhance the efficiency of a wave pattern of the ultrasonic energy. In addition, preferably the grid is formed to direct energy laterally from the axis of the transducer.

The above-mentioned objects are also achieved by providing an occupancy sensor comprising a passive infrared sensor, which has a mounting plate with a window to allow infrared energy to pass through the infrared sensor, the mounting plate has a raised guide , and a lens with a front wall and four side walls configured to be placed on the elevated guide.

Other objects, advantages and features of the invention will be apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the accompanying drawings, describes the preferred embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the invention and the advantages of some embodiments thereof, reference is now made to the following description taken together with the accompanying drawings, which form part of this application and in where: Figure 1 is a front perspective view, on the right side of the occupancy sensor unit according to an embodiment of the present invention; Figure 2 is an exploded perspective view of the occupation sensor unit shown in Figure 1; Figure 3 is an elevation view of the lower part in partial cross section of the occupancy sensor which is shown in Figures 1-2, showing the air gap switch in the closed position; Figure 4 is an elevation view of the lower part in partial cross section of the occupancy sensor shown in Figures 1-3, showing the air gap switch in the open position; Figure 5 is a side elevation view in partial cross section of a conventional occupancy sensor showing the ultrasonic transducers positioned away from the grid of a fascia closure plate; Figure 6 is a front elevation view of the occupancy sensor that is shown in Figures 1-4; Figure 7 is an elevation view of the upper part taken in partial cross section along line AA of the occupancy sensor which is shown in Figure 6 showing a pair of ultrasonic transducers positioned very close to the fascia grid; Y Figure 8 is a side elevational view in partial cross section along line B-B of the occupancy sensor which is shown in Figures 6-7 and showing an ultrasonic transducer very close to the fascia grid.

In all the drawings, the same reference numerals of the drawings will be used to refer to the same elements, characteristics and structures.

Detailed description of the exemplary modalities Aspects defined in the description, such as a detailed construction and elements, are provided to help understand the embodiments of the invention. Accordingly, those with ordinary skill in the art will recognize that various changes and modifications may be made to the described modes, without departing from the scope and spirit of the invention. Also well-known descriptions of functions and constructions are omitted to give clarity and brevity.

Figures 1-2 illustrate an occupancy sensor unit 10 according to the embodiment of the present invention. The occupancy sensing unit 10 includes a housing 12, a sensor module 18, a mounting plate 30, a lens 44, and a closure plate of the fascia 56.

The housing 12 comprises an interior cavity 14 defined by an upper wall, a lower wall, a rear wall and two side walls. Within the inner cavity 14 several support structures are located as mounting flanges to support the components of the unit. In the exemplary embodiments, two tabs 16a and 16b extend from the upper and lower wall along a parallel plane towards the rear wall. In other words, each flange extends laterally from the side walls. Each flange 16a and 16b has an opening therein for receiving a conventional fastener such as a screw for mounting the housing 12 on a bearing surface. Preferably, the housing 12 is mounted on a support surface such as the wall of a building. Preferably, the housing 12 is rectangular, however, any suitable polygonal shape can be used.

As can best be seen in Figure 2, the mounting of the occupancy sensor 10 has a sensor module 18 comprising an energy board 20 and a sensor board 22. The energy board 20 implements the power supply, and the circuit breakers of the ignition function. The sensor board 22 and the energy board 20 are connected through a transverse channel (not shown). The sensor board 22 communicates relay control and an oscillator signal from the power supply to the power board 20. The energy board 20 communicates DC power and a zero-pass AC voltage signal to the sensor board 22.

Among several other components of the circuits, the occupancy sensors are mounted on a top surface of the sensor board 22, as is commonly known in the art. The occupancy sensors can be any sensor parameter known in the art, such as a passive infrared (PIR) sensor, an ultrasonic sensor, a temperature sensor, light sensor, relative humidity sensor, sensor for the detection of carbon dioxide or other gases, an audio sensor, or any other passive or active sensor that can be used to detect movement or change in the nominal environment.

In the exemplary embodiment, a double occupation sensor is used incorporating a PIR sensor 24 and two ultrasonic sensors 26 and 28; however, it must be understood that other suitable arrangements and constructions can be used. The PIR sensor 24 is located in the center. Each of the ultrasonic sensors 26 and 28 is located on the PIR sensor 24 near the upper end of the sensor board 22. As shown in Figures 6-8, the two ultrasonic sensors 26 and 28 are arranged adjacent to one another. A dividing flange 29 (Figure 7) is located between the two sensors 26 and 28. Examples of conventional dual technology sensors are described in HUBBELL H-MOSS Occupancy Sensor Assemblies, catalog numbers ATD12771 and ATD1277W.Returning to Figure 2, the sensor board 22 also has a switch 31 placed on a top surface. Switch 31 is used to prevent the relay contacts in the unit from closing. Thus, when the switch 31 is disabled or in the open position, the occupancy sensor unit 10 is in the disabled state. So when an adjustment or maintenance in a controlled function is required, the closure plate of the fascia 56 is removed. Then, the switch 31 is moved to the disabled position and the push button switches are pressed to disable the electrical energy of the function. Consequently, the technician is protected against injuries, such as having an electric shock when servicing the controlled function.

Preferably, the energy board 20 and the sensor board 22 are rectangular, however any suitable form may be used.

Figure 2 also illustrates a mounting plate 30. The mounting plate 30 has upper and lower surfaces. Two openings 32 and 34 extend through the upper and lower surfaces of the mounting plate 30. A wall 36 and 38 extends continuously and outward from each opening. Each wall 36 and 38 extends perpendicularly away from the upper surface of the mounting plate 30. Each wall 36 and 38 preferably has an annular shape and has a predetermined depth.

Depending on the depth of the walls 36 and 38, the ultrasonic sensors 26 and 28 are placed through the openings 32 and 34 and a predetermined distance from the closing plate of the fascia 56. Varying the location and depth of the sensors ultrasonic sensors 26 and 28, the ability of ultrasonic sensors 26 and 28 to transmit sonic energy can be affected in a positive manner.

An elevated guide 40 is placed centrally on the mounting plate 30. The raised guide 40 has four walls with internal and external surfaces. The inner surfaces taper inward and define an infrared energy window 42. The window 42 receives energy by means of which, the PIR sensor 24 can see the environment through the lens 44. Accordingly, the raised guide 40 places advantageously the lens 44 in relation to the PIR sensor 24 so that the focal point of the lenses 44 is optimized for the PIR sensor 24 at the desired wavelength. The outer surfaces are vertical walls configured to slidably engage the structural walls 46 of the lens. The raised guide 40 has an advantageous shape for supporting the lens 44 and preventing the lens 44 from deforming under the pressure exerted by external forces such as that of a finger.

The projections 48 extend from an upper surface of the mounting plate 30 for insertion into an aperture in a projection 50 of the lens 44. These projections 48 also support placing the lens 44 relative to the PIR sensor 24.

The lower end of the mounting plate 30 includes a slot 52. Preferably, the slot 52 is substantially rectangular. The slot 52 extends through the upper and lower surfaces of the mounting plate 30 to receive the switch 31. The mounting plate 30 is preferably substantially rectangular, however, any suitable shape can be used. Except for the configuration described above, the mounting plate 30 and its connection to the sensor module 18 is generally known in the art.

The lens 44 is positioned in front of and in the field of view of the PIR sensor 24. The lens 44 focuses on the infrared radiation. When the PIR sensor 24 is used, preferably the lens 44 is a Fresnel lens; however, the lens 44 may vary with the different types of sensors.

The lens 44 is molded into a five-walled box structure. The front wall 54 contains the optics. The front wall 54 is substantially curved to increase the mechanical stiffness of the lens 44. The curvature also increases the lens area for optical gain. Four of the sides are structural walls. The structural walls are practically vertical and extend to the lower surface of the front wall 54 almost curved. The five-walled box structure acts to slidably engage the outer surfaces of the vertical walls of the raised guide., and form a cover over the window 42 of infrared energy. As indicated above, the raised guide 40 has an advantageous shape for supporting the lens 44 and for preventing the lens 44 from deforming under the pressure exerted by external forces.

The projection 50 having an opening extends perpendicularly from at least one of the structural walls. The projections 48 of the mounting plate 30 are inserted into the opening. Thus, the lens 44 is held in place by the projections 48 relative to the mounting plate 30 and the PIR sensor 24.

A closure plate of fascia 56 is shown in Figure 2. The closure plate of fascia 56 is removable and provides an interface between ultrasonic transducers 26 and 28 and ambient air in a controlled space. The openings in an upper part of the closure plate of the fascia form a carrier structure of the grid 58. The supported grid 58 has predetermined size, depth and shape. The energy flows through the individual ports to and from the ultrasonic transducers 26 and 28. The example shape of the supported grid 58 distributes the transducer energy more toward the ends than the energy pattern of a transducer per se and of a grid of the closure plate of the conventional fascia. This creates a desirable amplitude of the ultrasonic detection interval pattern.

For example, in Figure 5 a conventional occupancy sensing unit 60 is illustrated. First, the ultrasonic transducers 62 and 64 are mounted perpendicular to the sensor board 22, in a conventional occupancy sensor unit 60. The annular rings 72 and 74 extend beyond a front surface of the ultrasonic transducers 62 and 64. Thereafter, the supported grating depth 76 is relatively low, thus leaving a relatively large gap 78 between the ultrasonic transducers 62 and 64 of the front surface and the grid 76. These arrangements allow the ultrasonic energy to continue in the direction in which it is emitted from the ultrasonic transducers 62 and 64, that is, practically forward and not laterally.

As can best be seen in Figures 6-8, the ultrasonic transducers 26 and 28 are positioned on the lens 44 and are substantially parallel to one another. The supported grid 58 is relatively deep and the rear end of the individual louvers does not extend beyond a front portion of the ultrasonic transducers 26 and 28. Instead, a divider flange 29 (Figure 7) extends between the transducers ultrasonic transducers 26 and 28. In addition, the ultrasonic transducers 26 and 28 are located very close to the supported grid 58. Placing the ultrasonic transducers 26 and 28 parallel to each other very close to the supported grid 58 increases the efficiency of the wave pattern ultrasonic spreading the waves further to the sides of the occupancy sensor unit 10.

The closure plate of the fascia 56 also includes an aperture of the lens 78 for receiving the PIR lens 24 and transmitting infrared energy therethrough. The opening of the lens 78 is preferably located in the center and its shape is practically rectangular. Preferably, the lens 44 fits snugly when placed within the aperture of the lens 78; however, any suitable arrangement or construction can be used.

The lower part of the closure plate of the fascia 56 preferably includes two manually operated transfer switches 80 and 82 for transferring the automatically selected state control of the controlled output circuits.

All manual control of the circuits returns to the initial position after the occupation ends. The reason why there are two hand-operated transfer switches 80 and 82 is that some state and local energy construction / conservation laws require the installation of two light switches in the construction or reconstruction of offices, each for control a different part of the ceiling lighting. The rationale behind that requirement is that, in the interest of conserving energy, employees and cleaners have the opportunity to use half the light they would normally use in their daily activities. Depending on the amount of daylight available, employees working in a room may select the use of only half the group of available lights.

As best seen in Figures 3-4, the closure plate of the fascia 56 has an interior surface. A flange of the fascia 84 extends outward from one side of the inner surface to prevent a technician from leaving the switch 32 in the open position. As mentioned before, switch 32 is used to prevent the relay from closing the contacts. Thus, when the switch 32 is moved to the disabled position, the occupancy sensor unit 10 will be in the disabled state (Figure 4). Then, when an adjustment or maintenance of the function is required, the closure plate of the fascia 56 is removed. Then, the switch 32 is moved to the disabled position so as not to allow the electric power to pass to the function and protect the technician. against damage, like an electric shock.

When the technician terminates service or maintenance, he must allow the switch 32 to close to reconnect the power (Figure 4). However, very often the technician will forget to do it. As a result, the occupancy sensor unit 10 is reassembled without reconnecting the power. To prevent this from happening, the flange of the fascia 84 interferes with the switch 32 when it is in the disabled position. Therefore, the technician can not reassemble the occupancy sensor unit 10 while the switch 32 is in the disabled position.

Preferably, the closure plate of fascia 56 is substantially rectangular, however, any suitable shape can be used. Additionally, it is preferable that the closure plate of the fascia 56 be clutched with snap fit with the housing 12.

While the invention has been shown and described with respect to certain embodiments thereof, those skilled in the art should understand that various changes can be made in form and detail without departing from the spirit and scope of the invention as defined. in the following claims.

Claims (19)

1. An occupancy sensor comprising: a housing with an interior cavity, a switch configured to be placed in the open and closed positions, the switch practically mounted in the interior cavity of the housing; and a fascia closure plate configured to be placed in the housing for closing the interior cavity, the fascia has a fascia flange on the interior surface, the fascia flange is arranged to interfere with the switch in the open condition of the fascia. This avoids placing the fascia closure plate in the housing.

2. The occupancy sensor according to claim 1 further comprising a sensor module mounted within the interior cavity to support the switch.

3. The occupancy sensor according to claim 2 wherein the sensor module includes an energy board and a sensor board.

4. The occupancy sensor according to claim 1 further including at least one ultrasonic transducer mounted on a sensor board.

5. The occupancy sensor according to claim 1 further comprising an infrared sensor mounted on the sensor board.

6. An occupancy sensor to detect occupancy in a controlled space, including: at least one ultrasonic transducer; and a fascia closure plate for covering the transducer, the closure plate of the fascia has a grid to allow the transmission of ultrasonic energy between at least one ultrasonic transducer and the controlled space; wherein at least one ultrasonic transducer is positioned very close to the grid to enhance the wave pattern efficiency of the ultrasonic energy.

7. The occupancy sensor according to claim 6 wherein the grid has a depth.

8. The occupancy sensor according to claim 6, wherein the closure plate of the fascia has a flange of the fascia placed on an interior surface thereof.

9. The occupancy sensor according to claim 6 wherein at least one transducer extends through an aperture arranged on a mounting plate.

10. The occupancy sensor according to claim 6 wherein are two ultrasonic transducers, and the two ultrasonic transducers are placed adjacent to each other.

11. The occupancy sensor according to claim 6 wherein the closure plate of the fascia further includes a divider between the transducers.

12. The occupancy sensor according to claim 6 wherein a rear end of the grid does not extend beyond a front end of the at least one ultrasonic transducer.

13. An occupancy sensor that includes: an infrared sensor; a mounting plate with a window that allows energy to pass through the infrared sensor, the mounting plate has a raised guide; and a lens with a front wall and four side walls configured to be placed on the raised guide.

14. The occupancy sensor according to claim 13, wherein the front wall of the lens is substantially curved.

15. The occupation sensor according to claim 13 wherein the guide has four practically vertical walls.

16. The occupation sensor according to claim 13 wherein the vertical walls extend to the lower surface of the practically curved wall.

17. The occupancy sensor according to claim 13 wherein the mounting plate has a slot.

18. The occupancy sensor according to claim 13 wherein the mounting plate has at least one opening.

19. The occupancy sensor according to claim 13 wherein further includes an ultrasonic transducer, and the ultrasonic transducer extends through the mounting plate.