Patent Application
20110139282
Not Applicable
Not Applicable
1. Field of the Invention
The present invention relates to touchless faucets, and more particularly to such faucets that employ a light beam to sense presence of a person and activate the faucet in response to that sensing.
2. Description of the Related Art
In hospitals, public rest rooms, and other facilities, it is commonplace to provide a faucet which is turned on and off without requiring the user to touch the faucet. The prior art is replete with devices for sensing the presence of a user and, in response thereto, activating a solenoid valve assembly that controls the flow of water to a faucet. A common sensing technique, as described in U.S. Pat. No. 4,915,347, involves transmitting an infrared light beam into a flow region underneath the outlet of the faucet spout, where a user's hands or other objects are placed for washing. A hand or object so placed reflects some of the infrared light beam back toward the faucet, where that reflected light is detected by a sensor mounted either on or adjacent the faucet. Detection of reflected light at the sensor indicates the presence of a user in front of the faucet. In response to receiving the reflected light, the sensor emits an electrical signal that causes the solenoid valve to open, sending water from the faucet. When the detection of reflected light ceases, the solenoid valve is de-energized, terminating the flow of water.
A problem with such proximity activated faucets is that room elements near the faucet, such as a mirror or shiny sink surfaces, can reflect light back to the sensor, thereby falsely triggering the flow of water. Inanimate objects, such as handbags, placed on the front edge of the sink also can falsely cause faucet operation. The false activation of the faucet not only wastes water, but may result in water overflowing the sink, if an unattended object also is blocking the drain opening
Prior touchless faucets were not practical for kitchen sinks which are used for operations, such as draining water from a cooking pot or cutting vegetables, during which water from the faucet is not desired. Thus during such activities, the presence of a hand or other object beneath the faucet outlet should not activate the flow of water.
A faucet assembly includes spout having a base for mounting adjacent a basin of a sink. The basin is the recessed portion of the sink that is designed to receive and retain water. The spout projects upward and away from the base over the basin and terminates at an outlet from which a stream of water is to be produced in a flow region beneath the outlet. A light emitter and a light sensor are mounted to the spout. The light emitter projects a beam of light toward the spout base without the beam of light intersecting the flow region beneath the spout where the water sprays from the outlet. The light sensor produces a signal indicating whether the beam of light is striking the light sensor. In response to the signal, a control circuit opens a valve, thereby conveying water through the spout.
In one embodiment of this faucet assembly, the light sensor is mounted to the spout base and the light emitter is mounted proximate to the spout outlet with the light beam directed at the light sensor. Here, a person interrupts the light beam, with his or her hands for example, which interruption is indicated by the signal from the light sensor. The control circuit responds to that signal by opening a valve which supplies water to the faucet spout. The light may be in the visible spectrum to provide an indication to the person when the hands have interrupted the light beam. The water valve may remain open until either a predefined time interval elapses or the light beam is interrupted again, which ever occurs first.
In another faucet assembly embodiment, the light emitter and light sensor are proximate to each other on the spout and the light sensor responds to the reflection of the light beam by an object, such as a person's hands. In this case, the control circuit opens the valve in response to the signal indicating receipt of the light beam by the light sensor. Here too, the water valve may remain open until either a predefined time interval elapses or the light beam is interrupted again, which ever occurs first.
Because the light beam does not intersect the flow region beneath the spout where the water sprays from the outlet, a person can use the sink without triggering the flow of water. For example, the person may wash dishes in water retained in the sink or empty a pot of water without impinging the light beam and activating the faucet. Thus the faucet assembly is particularly adapted for use at sinks where activities other than washing hands occur.
With initial reference to
A light emitter 30, such as a semiconductor laser, light emitting diode (LED) or other device that emits a beam 32 of light, is mounted on the spout 14 adjacent the water outlet 22 and facing the base 18. The light emitter 30 is oriented to direct the light beam 32 in a downward angle toward the base. A light sensor 34 is located on the base 18 at a position to receive the beam 32 of light. For this embodiment, a semiconductor laser has the advantage of producing a highly collimated, narrow light beam 32 whereby most, if not all, of the light impinges the sensor 34. Nevertheless light from another type of emitter that is focused into a narrow beam also may be used. Such as narrow light beams provides a relatively small object detection zone along the path of that beam. Preferably, the light is visible to the human eye, so that when a hand of a user or other item blocks the light beam 32, a visible spot of light appears on that object to indicate that the beam has been interrupted. Nonetheless, a beam of invisible light, such as in the infrared spectrum, can be utilized. Alternatively, the locations of the light emitter 30 and the sensor 34 can be reversed, wherein the light emitter is mounted on or proximate the base 18 and the sensor is on or proximate the spout, however with this variation a spot of light on the hands may not be visible to the user. This alternative also may allow some of the emitted light to travel visibly across the room in which the sink 16 is located.
Operation of the faucet assembly 10 is controlled by an electrical circuit 40 shown in
The control circuit 46 preferably is microcomputer based and has a memory that stores a control program which governs operation of the faucet assembly 10 and stores data used by that control program. Inputs of the control circuit 46 are connected to a user input device 50 that in the illustrated embodiment is a touchpad, such as commonly found on laptop computers for the user to move a cursor on the display screen. The touch pad produces output signals indicating a two dimensional location on the surface of the touch pad that is touched by the user. The X signal for one orthogonal axis of touch pad indicates the desired temperature of the water discharged from the faucet 11, while the Y signal for the other orthogonal axis indicates a desired flow rate of that water. By touching different locations on the touchpad the user is able to change the temperature and flow rate. Alternatively conventional pushbutton switches can be employed as the user input device 50 by which the user increases and decreases the water temperature and flow rate. Pushbutton switches also may be provided for selecting preset water temperatures or flow rates that have been programmed into the control circuit 46.
When the faucet 11 is not being used, the light beam 32 travels from the emitter 30 to the light sensor 34, thereby producing an electrical signal that is applied to an input of the control circuit 46. As long as the control circuit 46 receives that electrical signal, a determination is made that a user is not present at the faucet 11 and the water is not permitted to flow to the faucet spout 14.
Referring again to
The path of the light beam 32, by avoiding the flow region and work region, allows a person to use the sink without activating the water flow. For example, a large pot of water may be emptied into the sink or dishes can be washed in water retained in the basin without that activity interrupting the light beam 132 and thereby triggering the water flow. As used herein the “flow region beneath the outlet” refers to the space under the faucet spout where an object is placed so that water from the outlet will impinge upon the object and excludes other spaces below the vertical location of the outlet where water from the outlet will not strike an object placed there. Although in first faucet assembly 10, the light sensor 34 is lower than the water outlet 22, the sensor is set back toward the rear of the sink, so that the light beam 32 that is aimed at the sensor does not intersect the flow region beneath the outlet 22 that is defined by the outlet water stream 26.
When a user approaches the sink 16 and desires to activate the faucet 11, his or her hand or another object is placed between the light emitter 30 and sensor 34, thereby interrupting the light beam 32. The path of the narrow light beam 132 defines a detection zone. As noted previously, it is preferred that the light is in the visible spectrum so as to produce a perceptible spot of light on the object to indicate to the user that the light beam is blocked. Furthermore, this spot is visible to the user because the light travels from adjacent the water outlet 22 of the faucet downward toward the back of the sink basin 24 and near the tubular base 18 of the faucet spout. This path illuminates a portion of the hand or the other object that is visible to the user.
Referring again to
The amounts to which the hot and cold solenoid valves 61 and 62 are opened are specified independently by respective first and second values stored within the memory of the control circuit 46. Those values are set by the signals from the user input device 50 and are used by the control circuit to determine the magnitude of the control signals sent to the valve drivers 56 and 58 and thus the level of electric current applied to each proportional solenoid valve 61 and 62. With reference to the orientation of the touch pad 52 in
Touching different locations along the vertical axis of the touch pad 52, oriented as in
Reference herein to directional relationships and movements, such as horizontal and vertical, up and down, or left and right, refer to a relationship and movement associated with the orientation of components as illustrated in the drawings, which may not be the orientation of those components when installed on or near a sink.
After interruption of the light beam has been indicated either by a spot of light on the user's hand or by water commencing to flow from the faucet, the hands of the user can be removed from blocking the light beam. Once activated, the faucet 11 may remain open for a fixed period of time, as determined by a software timer implemented by the microcomputer within the control circuit 46. During that time period, the control circuit continues to periodically activate the light emitter 30 and inspect the signal produced by the light sensor 34. If the user interrupts the light beam 32 again while water is flowing from the spout 14, the two solenoid valves 61 and 62 are closed immediately even though the fixed period of time has not elapsed. Alternatively, the faucet assembly 10 could be configured so that the two solenoid valves 61 and 62 remain open only while the light beam 32 continues to be interrupted.
A person may use the sink without turning on the water. The person may work underneath the spout outlet 22 and not activate the water flow because the light beam does not intersect the flow region beneath the outlet 22 or the larger work region 66. Thus the person may peel vegetables, place dishes in the sink, or empty a pan of water without water flowing from the spout. The location of the detection zone defined by the path of the light beam 32 allows such use of the sink. Anytime that water flow from the spout 14 is desired, the user simply moves a hand or other object through the detection zone defined by the light beam 32, thereby momentarily interrupting the light beam.
Referring to
A proximity detector 130 is mounted on the spout 114 near the second end 119 and faces the base 118. The proximity detector 130 incorporates a light emitter, such as a light emitting diode (LED), and a light sensor similar to components 30 and 34 in the first faucet assembly 10. The light emitter and light sensor are arranged near to each other so as to project a narrow beam 132 of visible light downward toward the spout base 118 and sense any light that is reflected back to the detector by an object 133, such as a user's hands, that may be placed in the light beam. The path of the light beam 132 forms a detection zone which does not intersect the flow region beneath the water outlet 122, through which the outlet water stream 26 flows, nor does the light beam intersect the work region of the sink.
The second faucet assembly 110 includes a manually operated mixing valve 134 that is mounted on the rim of the sink adjacent the mounting plate 112. Alternatively, the mixing valve could be incorporated into the tubular base 118 of the spout 114 as long as a separate outlet is provided for an automatic mixing valve assembly 147, as will be described. With reference to
The second outlet 146 is connected to an electrically operated valve assembly 147 having a single solenoid valve that couples the second outlet to the inlet 148 of the spout 114. Operation of the valve assembly 147 is governed by a controller 150 that includes a control circuit 152 for operating a valve driver 154 connected to the valve assembly 147. The control circuit 152 has an output connected to a light emitter 156 and an input connected to a light sensor 158, wherein the light emitter and the light detector are parts of the proximity detector 130. The controller 150 includes a power supply 159, such as a battery.
The second faucet assembly 110 can be operated automatically in a similar manner as the first faucet assembly 10 by placing a hand or other object in the light beam 132. Such action reflects light back to the sensor within the proximity detector 130. Since light from that light beams only strikes the sensor 158 when an object is present, the control circuit 152 only receives an active signal from the light sensor at that time. At such time, the control circuit responds by sending an output signal to the valve driver 154 that responds by opening the valve assembly 147 to feed the mixture of hot and cold water from the second outlet 146 of the mixing valve 134 to the inlet 148 of the spout 114. The amount that the valve assembly 147 is opened, and thus the flow rate of the water, is preset in the control circuit. Note that the water temperature is determined by the mixing stage of the manual mixing valve 134. Thereafter, the control circuit 152 closes the valve assembly 147 upon either the user again placing a hand or other object in the light beam 132 or after a predefined activation time period has elapsed, whichever occurs first.
The second faucet assembly 110 can be operated manually by the user lifting the lever 144 which opens the flow control valve stage of the mixing valve 134. The amount that the lever is raised determines the degree to which the flow control valve stage opens and thus the flow rate of the water. The flow control valve stage of the mixing valve 134 is connected in parallel with the electrically operated valve assembly 147, thus when either one is open water flows from the intermediate chamber of the mixing valve to the faucet spout 114 and water outlet 122. Regardless of which one of the manual mixing valve 134 or the electrically operated valve assembly 147 is open, rotating the lever 144 of the mixing valve 134 controls the temperature of the water fed to the water outlet 122.
The outlet 184 of the mixing valve 182 is connected to the inlet of the electrically operated valve assembly 147, thus those two valves are fluidically connected in series. To turn on the faucet, a user must raise the lever 186 to open the mixing valve 182. This action also closes the internal electric switch of the mixing valve which sends the valve signal to the control circuit 152 indicating that the mixing valve has been opened. The control circuit 152 responds to that valve signal by opening the electrically operated valve assembly 147 to the fully open state. This sends the mixture of water from the mixing valve 182 to the faucet spout 114 and through the water outlet 122. The user does not have to place a hand or other object in the path of the light beam 132 for this water flow to commence.
Now, however, if the user places a hand or other object in the path of the light beam 132, the resultant signal from the light sensor 158 causes the control circuit 152 to close the electrically operated valve assembly 147 and turn off the water flow. If the mixing valve 182 remains open, as indicated to the control circuit 152 by the valve signal on cable 188, removing the hand or other object from the light beam and then reinserting that hand or object into the light beam again causes the control circuit to open the valve assembly 147. Interrupting the light beam repeatedly, toggles the valve assembly 147 between open and closed states as long as the control circuit 152 continues to receive a valve signal indicating that the mixing valve 182 is open.
The foregoing description was primarily directed to a preferred embodiment of the invention. Although some attention was given to various alternatives within the scope of the invention, it is anticipated that one skilled in the art will likely realize additional alternatives that are now apparent from disclosure of embodiments of the invention. Accordingly, the scope of the invention should be determined from the following claims and not limited by the above disclosure.
