Sensor for washroom device with a non-circular sensing zone

A washroom device sensor uses at least one infrared beam that forms a longitudinal, rather than spot-shaped, sensing zone for detecting the presence of a user. The increased detection area of the longitudinal sensing zone ensures that at least a portion of the beam will contact a user using the washroom device. The beam may be adjustable in two or more directions to generate two or more sensing zones in different positions, allowing optimization of the sensing zone location with respect to a particular washroom device and the anticipated position of the device user.

TECHNICAL FIELD

The present invention relates to sensors for electronic control of washroom devices, and more particularly to a sensor that detects the presence of a user of a washroom device.

BACKGROUND OF THE INVENTION

Many public washrooms have incorporated sensors that automatically operate various washroom devices, such as urinals, water closets, hand dryers, faucets, and soap dispensers. Sensors are particularly useful when coupled to a flush valve, allowing urinals and water closets to be flushed without manual operation by the user. Generally, sensors transmit an infrared beam in a desired direction; if the beam is reflected from a user of the device back toward a receiver in the sensor, power is applied to operate the washroom device (e.g. actuating a flush valve for a toilet, opening a faucet valve, etc.).

Currently used sensors transmit a beam having a spot-shaped sensing zone, which covers a small sensing area and/or has a low, diffused power density. The beam itself is pointed forward, creating a sensing zone that is directly in front of the flush valve on which the sensor is mounted. If the sensor is mounted on a water closet with a toilet, the height of the beam may cause the beam to miss a user if, for example, the user is seated rather than standing in the water closet and cause the sensor to fail to activate the flush valve. This may lead the user to believe that the sensor and flush valve are not working even when they are functioning normally.

Attempts to remedy this problem may entail adding a refractive layer that changes the infrared beam's direction. Although this change allows the beam to detect a user in a different position, there is still the possibility that the beam will miss the user (e.g., the beam may travel between a user's legs if the water closet is being used as a urinal). The refracted beam also does not allow the beam direction to be adjusted based on the type of washroom device on which the sensor would be mounted. Because different washroom devices have different predicted user positions, a sensor having a beam optimized in one direction for a given washroom device may not be optimized for another washroom device.

There is a desire for a sensor that can detect a washroom device user more accurately.

There is also a desire for a washroom device sensor that allows adjustment of a beam direction.

SUMMARY OF THE INVENTION

The present invention is directed to a washroom device sensor that uses at least one infrared beam to detect the presence of a user. The beam is spread to form a sensing zone having a longitudinal sensing zone, such as a linear, elliptical, or rectangular zone. The increased detection area of the longitudinal sensing zone ensures that at least a portion of the beam will contact a user using the washroom device.

In one embodiment, the sensor allows the beam direction to be adjusted between two or more positions to generate at least two sensing zones, such as a first sensing zone and a second sensing zone spaced vertically apart from the first sensing zone. A particular zone can be selected by either adjusting a position of a beam emitter itself, by changing a beam direction, or switching between two or more emitters that emit beams in different directions. By providing a beam adjustment mechanism, the inventive sensor can be adapted easily for different washroom devices requiring different user positions.

DETAILED DESCRIPTION OF THE EMBODIMENTS

FIGS. 1 and 2illustrate a sensor100and its operating environment according to one embodiment of the invention.FIG. 1illustrates the sensor100mounted onto a urinal102, but the sensor100can also be mounted in a water closet that can be used as both a urinal and a toilet, a sink faucet, hand dryer, soap dispenser, bathing apparatus (e.g., shower, tub) or any other washroom device. For simplicity, the term “washroom device102” will cover all possible devices that can be used in conjunction with the sensor100and is not limited to the urinal shown in FIG.1.

As shown inFIGS. 1 and 3, the sensor100is able to transmit a beam104that can be directed to cover at least two sensing zones106. In one embodiment, the beam104is an infrared beam that forms a longitudinal sensing zone106. Possible sensing zone shapes include a line, ellipse, rectangle, or any other shape having a width longer than its height.

By using a longitudinal sensing zone106rather than a spot-shaped zone, the inventive sensor100detects the presence of a user more accurately because the beam provides a larger detection range with a higher power density and makes it more likely for at least a portion of the beam's path to contact a user of the washroom device. The longitudinal sensing zone106allows detection of users even with variations in the user's height, proportions, and orientation relative to the washroom device102because the zone's shape ensures that at least a portion of the beam104will be reflected from a user using the device102back into the sensor100. As is clear from the figures. The longitudinal sensing zone having a cross-sectional shape that is non-circular with an elongated dimension in one direction, and a smaller dimension in another direction. By describing the sensing zone as “longitudinal.” applicant means that the sensing zone could be otherwise described as being non-circular with a cross-sectional shape having a first larger dimension in one direction and a shorter dimension in another direction.

The beam direction can be adjusted so that sensing zone106position is optimized for a given washroom device.FIGS. 1 through 4illustrate one embodiment where the beam104direction can be switched to create either a high sensing zone106aor a low sensing zone106b. As shown inFIG. 3, the high and low zones106a,106brespectively lie above and below a center point108of an optical range110rather than directly at the center point110. In one embodiment, the sensing zones106are about 6 inches long when viewed approximately 42 inches away from the sensor100.

FIG. 2is a cutaway view of a flush valve200incorporating the sensor100according to one embodiment of the invention. As is known in the art, flush valves are often used in conjunction with toilets and urinals. The sensor100is implemented via a circuit board202, at least one emitter204that emits the beam104, at least one receiver206that detects a beam reflected from an object (e.g., a user using the washroom device), and an optic structure208that correspond with the emitter204and the receiver206. The embodiment shown inFIGS. 2 and 4illustrate a sensor100that has two emitters204, one that emits a beam associated with the high sensing zone106a and one that emits a beam associated with the low sensing zone106b. Alternatively, the sensor100may incorporate a single emitter204whose beam direction can be adjusted (e.g., through an adjustable mounting structure) to form the high and low zones106a,106b. Providing vertical adjustability of the beam direction further improves the detection capabilities of the beam and allows the sensor to be adapted to different types of washroom devices that may have different optimal sensing zones, depending on the anticipated position of the device user (e.g., standing or sitting).

During installation of the sensor100to the washroom device102, the installer can select the beam orientation (e.g., high or low) that will provide a desired sensing zone location. The actual beam selection can be conducted via a switch, such as a DIP switch250(see FIG.4), or other beam adjustment means. Possible alternative beam adjusters may include other types of switches, electrical controllers, software, actuators, or any other mechanism that can change the beam direction from the emitter by controlling the emitter204itself and/or by controlling the optic device(s) (lens)210associated with the emitter204.

The optic structure208may include an optic device210associated with each emitter204. For example, if there are two emitters204, the sensor100may include two optic devices210, one associated with each emitter204. In one embodiment, each optic device210is a known collimating optic set having an optics lens that forms the emitter output into a fine, round beam, and a cylindrical lens that spreads the round beam horizontally to form a beam having a longitudinal sensing zone. Other optic devices210known in the art may be used to shape the emitter204output to form the desired sensing zone shape. Alternative embodiments may include multiple optic devices210associated with each emitter204or different ratios between the optic devices210and the emitters204.

In one embodiment, the emitters204and receivers206are grouped into emitter/receiver pairs212a. In the embodiment shown inFIGS. 2 and 4, the top emitter204and receiver206are arranged so that the receiver206lies above the emitter204, while the bottom emitter/receiver pair are arranged in a mirror image with respect to the top pair (i.e., where the receiver206lies below the emitter204). To prevent false triggering, the emitter/receiver pairs212a,212bare arranged inside a tunnel214having a compartment215for each pair212a,212b. The tunnel214ensures that the receivers206beams only from the front of the sensor100.

During installation of the/sensor100to the washroom device102, the installer can select the beam orientation (e.g., high or low) that will provide a desired sensing zone location. The actual beam selection can be conducted via a switch, such as a DIP switch, or other beam adjustment means. Possible alternative beam adjusters may include other types of switches, electrical controllers, software, actuators, or any other mechanism that can change the beam direction from the emitter by controlling the emitter204itself and/or by controlling the optic device(s)210associated with the emitter204.

In one embodiment, if the installer selects a low sensing zone106bas the desired zone, the emitter204in the pair212awill transmit the infrared beam through the top optic device. If a user is within the detection range of the beam, the beam will bounce off the washroom device user, travel through the bottom optic device and be detected by the receiver206in the bottom pair212b. Conversely, if the installer selects a high sensing zone106a, the beam will bounce off the user, travel through the top optic device and be detected by the receiver206in the top pair212a. If the sensor100incorporates a different number of emitter and receivers and/or if the emitters and receivers are arranged in a configuration different than that shown in the Figures, then the beam emission and detection patterns may be modified as well according to principles within those of ordinary skill in the art.

In addition to the sensor100circuitry itself, the flush valve200shown inFIG. 3includes a solenoid valve216coupled to the sensor100, a manual washroom device actuator215, and a housing230. The solenoid valve216can be actuated by the sensor100via any known manner. If the sensor100will be used with a washroom device other than a toilet, urinal, etc., then the sensor100would be coupled with other components specific to that washroom device.

To provide visual feedback to the user, the sensor100may also include a visible light source232, such as an LED. In one embodiment, the visible light source232is mounted above the optic structure208rather than within the tunnel214. The beam emitted by the visible light source232can simply be output through the housing230, without being transmitted through any optics. The visible light source232allows the user to determine whether he or she is correctly aligned with the sensor100by checking whether the light beam is visible on his or her body.

FIG. 4is a representative diagram of one circuit board202that can be used in the inventive sensor100. As explained above, the emitters204and receivers206can be arranged in pairs212a,212b, with each pair212a,212bplaced inside a compartment215of the tunnel214. In the embodiment shown inFIG. 4, the installer can select the beam direction, and therefore the sensing zone height, via a function selection switch250, such as a DIP switch, which connects the emitter/receiver pair212a,212bcorresponding to a selected sensing zone height with a power supply. The function selection switch250therefore allows selection of the beam direction without having to modify any optics within the sensor100. Any other control device may also be used to select an emitter/detector pair. If a single emitter204is used, to adjust the beam direction of the emitter204by, for example, changing the position of the emitter204itself or placing a refractive lens in front of the emitter204. A range adjuster302may also be incorporated to adjust the sensitivity of the sensor100by setting a threshold level at which the receiver206would recognize the presence of the reflected beam.

Although the above description focuses on incorporating the inventive sensor in a flush valve for a urinal or water closet, the sensor can be incorporated in any washroom device where automatic operation is desired (e.g., sink faucet, soap dispenser, shower, hand dryer, etc.) without departing from the scope of the invention.

It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the invention and that the method and apparatus within the scope of these claims and their equivalents be covered thereby.