Patent Application
20120167292
1. Technical Field
The present disclosure relates to a hands free system for lifting and lowering a toilet seat.
2. Discussion of Related Art
Public restrooms may be used by thousands of people daily and bacteria flourishes easily in these damp, moist environments. Restrooms are prime sources of contamination simply because of their function. Because bodily fluids can transmit disease, toilets are obvious contamination points.
For example, a user typically needs to make contact with the flushing handle of the toilet. Toilets presently exist that automatically flush themselves once a user is finished, enabling the user to avoid contact with the handle.
However, individuals may also be exposed to contaminants when they lift or lower the seat of the toilet. Thus, there is a need for a hands free system that can lift and lower a toilet seat, without the need for the user to make physical contact with the toilet.
According to an exemplary embodiment of the invention, an apparatus to lift and lower a seat assembly of a toilet includes a motion sensor that outputs a detection signal in response to observed motion, a motor assembly having a motor driving unit and a motor, where the motor driving unit is configured to drive a shaft of the motor in a clockwise or a counterclockwise direction using a direction signal based on the detection signal, a first gear located on the shaft such that a rotation of the shaft, rotates the first gear, a second gear located on an axle within the case and interfaced with the first gear such that a rotation of the first gear rotates the second gear, a drive shaft interfaced with the second gear and coupled to a lever such that a rotation of the second gear rotates the drive shaft, and the rotation of the drive shaft lifts or lowers the lever, and a bearing housing comprising a movable lead screw with a detent. Within the bearing housing, a first end of a first spiral spring is connected to a slot of the drive shaft, the first spiral spring is wrapped around the drive shaft, and a second end of the first spiral spring is located in a path of the detent.
According to an exemplary embodiment of the invention, an apparatus to lift and lower a seat assembly of a toilet includes a motion sensor that outputs a detection signal in response to observed motion, a motor assembly having a motor driving unit and a motor, where the motor driving unit is configured to drive a shaft of the motor in a clockwise or a counterclockwise direction using a direction signal based on the detection signal, a first gear located on the shaft such that a rotation of the shaft, rotates the first gear, a second gear located on an axle within the case and interfaced with the first gear such that a rotation of the first gear rotates the second gear, a drive shaft interfaced with the second gear and coupled to a lever such that a rotation of the second gear rotates the drive shaft, and the rotation of the drive shaft lifts or lowers the lever, and a rigid crank shaft mounted from a hub of the second gear to a hub of the drive shaft.
According to an exemplary embodiment of the invention, an apparatus to lift and lower a seat assembly of a toilet includes a motion sensor that outputs a detection signal in response to observed motion, a motor assembly having a motor driving unit and a motor, where the motor driving unit is configured to drive a shaft of the motor in a clockwise or a counterclockwise direction based on a direction signal, a first gear located on the shaft such that a rotation of the shaft, rotates the first gear, a second gear located on an axle within the case and interfaced with the first gear such that a rotation of the first gear rotates the second gear, a drive shaft interfaced with the second gear and coupled to a lever such that a rotation of the second gear rotates the drive shaft, and the rotation of the drive shaft lifts or lowers the lever, and a microcontroller that is configured to determine whether the detection signal represents a lifting command or a programming command. The microcontroller generates the direction signal when the detection signal represents a lifting command and performs an internal calibration when the detection signal represents the programming command.
Exemplary embodiments of the invention can be understood in more detail from the following descriptions taken in conjunction with the accompanying drawings in which:
b illustrates a part of the drive mechanism that uses a spiral spring according to an exemplary embodiment of the invention;
Exemplary embodiments of the present invention will be described below in more detail with reference to the accompanying drawings. This invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
The Detection Controller Unit 110 may include a PIR Detection Logic Module 102 and Re-Triggerable Time Delay Module 104. The Direction Controller Unit 140 may include a Direction Control Module 142, a Direction Memory Module 144, a Stall Sensor Module 146, and a Shutdown Control Module 148.
The apparatus is housed within a case. The case may be configured to fit between the bolts, the seat, and water tank of the toilet. In an embodiment of the present invention, the shaft of the Motor 150 exits the case and a lever of the lifting mechanism 160 is attached to the shaft via a coupler. The coupler may include a spring clutch. This embodiment will be discussed later in more detail with respect to
The case may be secured to a toilet such that a portion of the lever is positioned below a portion of the toilet seat assembly, at or near the axis of rotation of the assembly. Alternately, the case may be secured such that the lever is positioned under the toilet seat assembly to provide a new axis of rotation. The lever lifts or lowers the toilet seat and/or lid when the apparatus is activated by motion of a user (e.g., by motion of a hand near the PIR 100 of the apparatus).
The PIR 100 may be a pyro-electric device (e.g., sensor) that detects the motion by measuring changes in the infrared levels emitted by surrounding objects. The PIR 100 may have a predefined or configurable motion detection distance range (e.g., 0.5 meters) and detection angle (e.g., about 10 degrees to about 60 degrees). In an exemplary embodiment of the present invention, the detection distance is set to a defined area around the toilet. Alternately, ultrasonic or radio frequency means of detection may be used instead of infrared.
The PIR 100 may be disposed under an infrared filter window in a top cover of the case. The PIR 100 causes a change in its output voltage (e.g., a PIR signal) when it detects the arrival of infrared light, as when a hand is placed above the window. This output voltage may be sent to the PIR Detection Logic Unit 102, which analyzes the PIR signal to determine whether it meets certain criteria. For example, the criteria may specify a magnitude and length of a duration that would be associated with the presence and movement of a hand in the detection region above the window.
In the event that the PIR signal meets the criteria, the Re-Triggerable Time Delay Unit 104 (e.g., a re-triggerable OneShot) may be triggered to an ‘on’ state, and emit a control signal (e.g., a pulse with a positive leading edge) to turn on the Motor Power Supply Unit 130. The control signal may be set such that its minimum length assures that no other power-on command is issued during the ‘on’ time duration of the OneShot. However, if another acceptable PIR signal is detected during the normal ‘on’ time period of the OneShot, the time may be extended by a predetermined nominal ‘on’ time period of the OneShot. At the end of the period of time after the last trigger or re-trigger of the OneShot, the OneShot reverts to an ‘off’ state.
On receipt of the control signal (e.g., on receipt of the leading edge of the ‘on’ period of the OneShot), the Motor Power Supply Unit 130 is turned on. The Motor Power Supply Unit 130 supplies a voltage Vm to the Motor 150 via the Direction Control Module 142, which applies the voltage Vm to the motor coil of the Motor 150 to spin the shaft of the motor 150 in the clockwise rotation direction, or by reversing the side of the coil receiving voltage Vm, to spin the shaft in the counter-clockwise direction. The direction of rotation may be controlled by a Direction Memory Module 144 of the Direction Controller Unit 140, which commands either clockwise or counterclockwise rotation, which is reversed after completion of the last complete cycle of seat movement.
Since the lever is attached directly or indirectly to the shaft, and the lever is positioned under the seat assembly (e.g., the toilet seat), when the Motor Power Supply Unit 130 is turned on, rotation of the Motor 150 cause the seat to either lift or lower based on the direction that the shaft is rotated. The Direction Memory Module 144 stores the direction that the shaft is to be rotated to reverse the prior action and may store a default rotation direction initially. The Direction Control Module 142 uses this stored value to determine the direction that the shaft is to be rotated. Each subsequent triggering of the apparatus lifts or lowers the toilet seat in the opposite direction as it last traveled.
The lever is not permanently attached to the bottom of the toilet seat. As the lever lifts the seat, if the axes of rotation of the seat and lever are not properly aligned, the lever may slide along the bottom surface of the seat. A material that has a low coefficient of friction (e.g., Teflon) may be attached to the top surface of the lever to facilitate this sliding. When the lever is angled just short of a vertical position, due to gravity, the lever should remain in contact with the seat.
However, if the lever extends beyond the vertical position, the seat may fall away from contact with the lever (e.g., the seat may fall away to contact the toilet tank). This can be prevented by creating a point of resistance for the lever. For example, a fixed or adjustable interference can be attached to the case in the path of the lever to obstruct the path of the lever before it reaches a vertical position.
Based on the design of the toilet, when lifting the seat, the seat could contact the toilet tank before moving beyond a vertical position, and thus the added interference may not be necessary. When the toilet seat is lowered, the seat or lever will eventually make contact with the toilet bowl. Further, the lever may experience a contact when a user uses his hands or foot to stop the seat while it is being lifted or lowered or pushes the seat in a direction opposite to which it is being currently moved by the Motor 150.
However, after one of the above described contacts has been made, the Motor 150 may attempt to continue spinning its shaft, which may strip the gears of the Motor 150. Thus, the Motor 150 may be turned off when or soon after these points of resistance are reached. Once the seat has reached either the ‘up’ or ‘down’ position, or encounters an artificial point of resistance, the physical interference with continued rotation will cause the current of the Motor 150 to increase towards its highest level, which may be referred to as Stall current.
The Stall Sensor Module 146 can continuously monitor the current of the Motor 150. When the level of the current exceeds a predefined normal operating current level (NOCL) or the NOCL plus a predefined current offset CO, the Stall Sensor Module 146 may output a stall signal SS to trigger the Shutdown Control Module 148 to send a shutdown SD signal to power down the Motor 150. In one embodiment, the NOCL plus the CO is set below the level of the Stall current.
The Shutdown Control Module 148 may send the shutdown signal SD immediately to the Direction Control Module 142 and the Motor Power Supply Unit 130 in response to the stall signal SS. The Direction Control Module 142 toggles the up/down state of the stored rotation direction in response to the shutdown signal SD. The Motor Power Supply 130 is powered down in response to the shutdown signal. For example, assume that the seat moving down and encountering the natural resistance of the toilet bowl triggered the shutdown. The Direction Memory Module 144 would then have stored a rotation direction of ‘up’ in response to the shutdown signal (e.g., The Direction Control Module 142 toggles ‘down’ to ‘up’). When the PIR 100 is re-triggered due to motion, a new control signal would be generated by the Detection Controller Unit 110 to turn on the Motor Power Supply Unit 130, enabling the Motor Power Supply Unit 130 to again deliver the voltage Vm to the Direction Controller Unit 140. The Direction Control Module 140 would then apply the voltage Vm to the Motor 150 to spin its shaft according to the stored rotation direction (e.g., up), thereby causing the seat to lift upwards.
Alternately, the Shutdown Control Module 148 may be configured to output different shutdown signals of different time delays to the Direction Control Module 142 and the Motor Power Supply Unit 130 (e.g., a first shutdown signal and a second shutdown signal). For example, the Stall Sensor Module 146 may trigger a shutdown control operation of the Shutdown Control Module 148 by emitting a positive edge. The leading edge of the pulse may cause the Shutdown Control Module 148 to output the first shutdown signal to the Direction Control Module 142 having a first duration. At the expiration of the first duration, the Direction Control Module 142 toggles the state of the stored rotation direction. The leading edge of the pulse may cause the Shutdown Control Module 148 to delay for a predetermined period and upon expiration of the delay, output the second shutdown signal (e.g., a negative pulse) to the Motor Power Supply Unit 130, causing it to shutdown. In this way, the Direction Control Module 142 is able to toggle the storage state of the direction of rotation before the Motor Power Supply Unit 130 is powered down. If the Motor Power Supply Unit 130 is powered down without this delay, the Direction Memory Module 144 may not have enough time to update the state of the rotation direction. The shutdown operation includes the detection of the stall and the removal of power to the Motor 150. The shutdown operation is configured such that power is removed from the Motor 150 before the continued operation of the Motor 150 has enough time to damage its gears.
Each time the seat moves either from the ‘down’ position to the ‘up’ position or the ‘up’ position to the ‘down’ position is considered one complete cycle of the apparatus. At completion of one of these cycles, the apparatus is in an initial state of waiting for a PIR signal to start the next cycle of seat movement. At this time, the voltage Vm may be removed from the Motor Power Supply Unit 130 (e.g., Vm no longer supplied to Unit 130), thereby reducing the drain on the Battery 120. However, the DC Power Supply 125 can remain active to assure continued operation of the PIR 100. Battery power may be saved further by using a sleep mode to power down the circuits that remain active. For example, the DC Power Supply 125 could be disengaged from the battery 120 using a switch during the sleep mode and then re-engaged during a waking mode. For example, a third of every 100 ms of operation could correspond to the sleep mode and the other two thirds could correspond to the wake mode. This is merely an example, as the duty cycle of the apparatus may be changed as desired.
A filter window 255 is located in a wall (e.g., the Cover 205) of the Case 200. The filter window 255 may be alternately located in one of the side walls or the front wall of the Case 200.
The Battery Condition Indicator 135 may be located in a wall (e.g., a side wall) of the Case 200. The Battery Indicator 130 may be alternately located in the front wall or omitted. The Case 200 may include a Recharge Port 240 in a side wall for recharging the Battery 120. Alternately, the Recharge Port 240 may be located in the Cover 205, the front wall, or the rear wall. The Recharge Port 240 may be omitted (e.g., when a non-rechargeable battery is used). Alternately, an internal audible buzzer may be included within the Case 200 that sounds to indicate the need to recharge or replace the Battery 120.
An adjustable interference 270 may be attached on the same side of the Case 200 as the Coupler 220. The interference 270 is positioned such that it rests in the path of the Coupler 220 or the Lever 230 to interfere with the rotation of the Coupler 220 or the Lever 230. If the interference is positioned properly, as the Coupler 220 rotates, it will eventually contact the interference 270, and the Motor 150 turns off shortly thereafter. The interference 270 may have an asymmetric shape and be rotated to adjust the upper limit for the Lever 230. Alternately, a fixed interference may be used to fix the upper limit of the Lever 230.
The Case 200 may be attached to the Base 210 in various ways, such as welding, nails, screws, glue, solder, etc. The Base 210 may be configured to lie on the plane of the toilet. A seat assembly of the toilet (e.g., the Toilet Seat 260 and a Toilet Seat Lid) is typically mounted to a toilet bowl by means of two mounting bolts. The Base 210 is configured to mount under the seat assembly mounts and lie on the surface (e.g., ceramic) of the toilet bowl. The Base 210 is held in place by the same mounting bolts that are used to connect the seat assembly to the toilet bowl. For example, the Base 210 may include a left slot 212 and a right slot 214 that are spaced to correspond to spacing of the seat mounting bolts and dimensioned to receive the bolts. The slots 212 and 214 provide for installation of the apparatus without the need to fully remove the seat and lid mounts, and also for adjusting a relative distance between the front of the Base 210 and the rear of the Toilet Seat 260. In an alternate embodiment of the present invention, the slots 212 and 214 are replaced with corresponding holes (e.g., circular, oblong, etc.) to receive the mounting bolts. The slots 212 and 214 permit the Lever 230 to be moved nearer to or further from the Seat 260, permitting the rotation axis of the Lever 230 to conform more closely to the axis of rotation of the Seat 260.
As discussed above, the Motor 150 is internal to the Case 200 and either the shaft or a portion of a gear train (e.g., a rod) exits from a side or front of the Case 200. The Coupler 220 is installed on the shaft or rod. For example, the shaft may have a flat, which is engaged within the Coupler 220 by a spring and washer, which is forced by the spring onto the flat. The force of the spring may be controlled by advancing a bolt, entering the Coupler 220 from the top, and constraining the coupler to rotate as the shaft rotates. This spring assembly forms a clutch which permits the washer to be forced off the flat, if excessive force is applied by manual lifting or lowering of the seat 260, which force is transmitted to the coupler 220 via the Lever 230. This prevents such movement of the Seat 260 from applying external force to the gears of the Motor 150, which could cause damage to those gears. Thus the shaft is decoupled from the Coupler 220, and will be re-coupled when rotation of the shaft once again brings the washer in line with the flat, which permits the spring to force the washer up against the flat once more.
If, when the motor is not running under power, and the shaft is not decoupled from the Coupler 220, application of an excessive force to the shaft could damage the Motor 150 or its gears. When the motor is not running, the Stall Sensor Module 146 cannot sense when this excessive force is occurring by detecting an impending Stall Current and triggering the powering down of the Motor 150. Accordingly, when such force occurs, the clutch protects the Motor 150 by decoupling the Lever 230 and Coupler 220 from the Motor 150 or its Gear Train.
If the Seat 260 ever becomes hung in mid position after power to the Motor 150 is turned off, upon retriggering the PIR 100, the Seat 260 will either go up or down based the current state of the saved rotation direction (e.g., which may be stored in direction memory 144).
The Coupler 220 drives the Lever 230, which is positioned so that, with the Toilet Seat 260 down, the Lever 230 contacts the bottom side of the Seat 260. Then, when the Coupler 220 rotates in, for example, the clockwise direction, the Lever 230 exerts a lifting force on the bottom of the Seat 260, causing it to lift. When the Seat 260 is up, an alternate rotation of the shaft (e.g., in a counter-clockwise direction) causes the Lever 230 to disengage from the bottom side of the Seat 260.
If the position of the Seat 260 is less than vertical, gravity causes the Seat 260 to fall against the Lever 230 and follow it down. If the Seat 260 has been lifted past vertical (e.g., assume the interference 270 is not present or is improperly positioned), in an alternate embodiment of the present invention, a second part of the Lever 230 can be attached to the Coupler 220 to contact the top surface of the Seat 260, to exert a force to lower the Seat 260 when the shaft is rotated to lower the Seat 260 (e.g., in a counter-clockwise direction). Alternately, the Lever 230 can provide a flexible lanyard (e.g., a rope), attached to the bottom of the Seat 260 by tape or some other temporary attachment mechanism. When the shaft rotates in the ‘down’ direction, the lanyard can pull the Seat 260 to just below vertical, and then the Seat 260 will continue to follow the Lever 230 downward with the force of gravity.
In an alternate embodiment of the present invention, sensors may be attached to the Case 200 to detect the position of the Coupler 220. For example, the sensors would detect whether the Coupler 220 is about exceed vertical and could trigger a mechanism to restrain the Coupler 220 from going any further. The sensing means may include light or laser sensors, magnetic sensors, electrical contact sensors, etc.
The relationship between the current the Motor 150 draws from the Motor Power Supply Unit 130 and the speed and torque of the motor may be used to determine whether there is a need to stop the motor, or change the direction of rotation. For example, if the current drawn by the Motor 150 when starting from a standing position, either ‘up’ or ‘down’, is unique in magnitude and transient time behavior (e.g., the magnitude or transient behavior during a stall condition), this behavior can be used to permit the motor to continue in its initial direction, or change direction and continue until the Seat 260 reaches its final condition, either up or down, as evidenced by the detection of the Stall condition. The startup current, if the Motor 150 is being driven in the ‘up’ direction, with the Seat 260 down, will be larger than for other conditions or initial seat positions, and thus will be distinguishable in either magnitude or transient time behavior from a true Stall condition. If the current drawn by the Motor 150, when reaching a Stall condition is unique in magnitude and transient time behavior, its analysis can be used to cause the Motor 150 to either reverse or stop. The time interval between a last PIR activation and the event itself may be used to determine whether stopping or reversing the Motor 150 is the proper course of action. Further, a time delay may be used to delay examination of the motor current to prevent the startup current from falsely triggering the Stall Condition.
Since the apparatus is typically installed within a bathroom, where the availability of water makes the presence of high voltage AC power contraindicated, the Battery 120 (e.g., a 9 v) can be recharged from a portable battery supply (e.g., 12v), which itself has been kept on recharge. Many such batteries for multiple such apparatuses can be recharged from a single portable battery supply. The Battery 120 may be charged through the Recharge Port 240. For example, the Battery Indicator 130 may blink a color (e.g., red) using a light (e.g., an LED) to indicate the need for recharge.
The leading edge of signal TON may be differentiated and used to turn on the Motor Supply Unit 130 to generate a power control signal PowerOn. The power control signal PowerOn is then used to turn on the Motor 150, which outputs a signal MotorON. The motor power may be latched to the ‘on’ state, and can then be turned off when one of a Stall event or an End event occurs first. The Stall event is the detection of the Stall condition by the Stall Sensor Module 146, which generates a stall signal StallSensor. The end event may be the negative edge of signal Ton, when signal Ton signal
transitions from a logic high to a logic low. The length of signal TON may be configured to be long enough to ensure that the first event occurs first. The stall event starts a signal TD(X Dir) and reverses the control of motor direction sometime during the length of the stall signal StallSensor. This reversal opposes the Stall Sensor condition.
The Stall Event starts a time delay signal TD(PowerOff), which is longer than signal TD(X Dir) to assure that the motor direction control (direction controller 140) has completed is change of direction. At the end of signal TD(PowerOff), a latch of the Motor Power Supply 130 is released, and the Motor 150 stops, leaving the Seat 260 in its last position. If the End Event occurs first (e.g., signal TON ends before the Stall Event occurs), the negative differentiated edge of signal TON can be used to unlatch the Motor Power Supply 130, thereby stopping the Motor 150.
In an alternate embodiment of the present invention, a second PIR is included in the apparatus. The first PIR (e.g., PIR 100) and the second PIR (not shown) are used together to determine whether a user desires for the Seat 260 to move up or down. The 2 PIRs may be positioned to determine whether a hand has made a rightward motion or a leftward motion. For example, the first PIR could be positioned to the left of the second PIR, and triggering the first PIR with motion followed by triggering the second PIR within a certain time period may trigger the apparatus to move the Seat 260 downward. For example, the Detection Controller Unit 110 may be modified to receive outputs of both PIRs and determine whether the outputs suggest that an upward or downward motion of the Seat 260 is desired. Vice versa, triggering the second PIR with motion followed by the first PIR could trigger the apparatus to move the Seat 260 upwards. The 2 PIRs may alternately be positioned above and below one another, and then detection of motion from up to down could trigger the apparatus to move the Seat 260 downwards and detection of motion from down to up could trigger the apparatus to move the Seat 260 upwards. When two PIRs are used as described, the Direction Control Module 142 and the Direction Memory Module 144 may be omitted. For example, sensing of the stall current need not be used to determine the direction that the shaft is rotated. The Detection Controller Unit 110 can then be modified to apply the voltage Vm to the Motor coil of the Motor 150 to spin the shaft of the Motor 150 in the clockwise rotation direction, or by reversing the side of the coil receiving Vm, to spin the shaft in the counter-clockwise direction based on both outputs of the 2 PIRs.
Since a device according at least one embodiment of the above described invention is mounted to the toilet using the mounting bolts of the existing seat assembly having a standard separation distance, the device is considered a universally installable device. The device can be readily installed on the large population of already installed toilets, without physical alteration of either the seat assembly or the toilet itself. The device may be offered to OEM accounts to be provided as an add-on option to their current toilet seat designs without requiring modification of their standard production.
The Stall Sensor Module 146 monitors current of the Motor 150, and when the current increases to a value deemed by past experience to represent a Stall Condition, (e.g., when the Seat 260 has encountered an obstruction caused by reaching either the top or the bottom of its travel) the Module 146 sends a signal to the Micro 200 to indicate the condition is present, so that the Micro 200 can shut down power to the Motor 150, thus ending the operation. For example, the signal may indicate the current value of the motor current. Stopping the Seat 260 in mid travel by use of a hand will also cause the Micro 200 to end motor power, thus preventing the gears of the Motor 150 from stripping.
Different from the block diagram of
In an exemplary embodiment of the present invention, the battery 120 has a 6 volt output when fully charged. Over time and use of the apparatus, the battery 120 will gradually lose its charge. For example, the charge could eventually fall to 3.2 volts. The apparatus may optionally include a Voltage Booster 250, which can maintain a constant voltage (e.g., about 12 v to about 16 volt) to the Motor 150, regardless of the voltage of the Battery 120. The output of the Voltage Booster 250 is fed to the DC supply 125 (e.g., +5 volt) supply, which is used to operate the rest of the elements of the apparatus, even when the voltage of the Battery 120 falls below a threshold level (e.g., about 3.2 volts). Since all voltages are monitored by the Micro 200, the Micro 200 is able to control the operation of the Voltage Booster 250 to maintain all needed voltages in their required range, until the Battery 120 is essentially completely drained. Before the battery 120 dies, the Micro 200 can use the Battery Condition Indicator 135 to send out a signal to alert a user to change the Battery 120. In this way, a supply voltage (e.g., about 5 volts) to the computer chips may be maintained, even if the booster voltage drops to the threshold level (e.g., about 3.2 volts).
Referring to
According to an exemplary embodiment of the present invention, the pinion gear 701 may be pulled apart (e.g., disengaged) from the second gear 702 using a spring (not shown) and pushed together (e.g., engaged) using a solenoid (not shown). Since this pushing and pulling requires an axle of the first or second gear 701 or 702 to be able to move laterally, one of the corresponding supporting rods may include a slot that allows an axle of one of the gears 701 or 702 to be moved from side to side. The width of the slot is configured to be wide enough to allow the gears 701 and 702 to be separated from one another.
The Micro Controller U2 is programmed to react to the positive gate to perform the functions described below. For example, the Micro Controller U2 recalls the memorized direction that the Motor M1 (e.g., Motor 150 of
After turning the Power Switch U3 On or Off, the Micro Controller U2, causes transistor Q3 to turn transistor Q4 On. This delivers voltage Vm to Relay RLY 1. Depending on the energized or de-energized condition of the relay coil, the positive voltage Vm, will be applied to one or the other side of the Motor M1, corresponding to the Clockwise or Counter Clockwise rotation of the corresponding shaft.
Current of the Motor M1, whether rotating in either direction, is delivered to Ground via resistor R19. The voltage across R19 is therefore directly proportional to the current of the Motor M1. This current is a function of motor speed and torque. So, when the Motor M1 is stalled due to an obstruction, the current increases to a limit which may be termed the Stall Current. The Resistor R19 is bypassed by Capacitor C13 to insure that transients will not falsely cause a voltage spike that could be interpreted as a breaching of the Stall Current.
The voltage across Resistor R19 is delivered to the Micro Controller U2, which uses its A/D conversion function to create a digital number proportional to the current of the Motor M1. The Micro Controller U2 compares this number to an internally stored digital number N1, representing an amount of Motor current above which it can be declared that the Motor M1 is about to Stall. This Stall condition should not be permitted as it might damage the gears of the Motor M1. But, in any event, the condition means that the Seat 260 has reached the end of its travel and is being restricted from further lifting or lowering by a physical obstruction. For example the obstruction could be either the Toilet itself, if going Down, or the Water Tank, or other obstruction, if going Up. So, on breaching this predetermined Stall threshold, the Micro Controller U2 shuts off transistor Q4, terminating the On state of transistor Q3 and terminating the rotation of the shaft.
In an exemplary embodiment of the present invention, the battery 120 is a 6 volt battery and supplies power to each element of the apparatus. This may avoid the need to create a separate power supply to operate the individual elements, which may operate in one embodiment between 4.5 and 5.5 volts, and up to a 7 volts maximum. Thus all elements of the apparatus can be operated directly from the Battery 120 via a Diode D5, which can be used to reduce the voltage from 6 volts to 5.4 volts. When the battery 120 is 6 volts, it may comprise four 1.5 volt cells (e.g., AA, C, etc).
In an exemplary embodiment of the present invention, the Motor M1 (or 150) is provided as a 12 volt device. In an exemplary embodiment where the Motor 150 is 12 volts and the battery is 6 volts, 12 volts is created from the 6 volts to operate the Motor 150. This may be accomplished by embodying the Voltage Booster 250 as a Voltage Doubler. Alternatively a Voltage Booster 250 can be used, which not only produces an output voltage greater than 6 volts, but maintains this high voltage essentially independent of the gradually declining battery voltage, as its capacity is used up.
The Voltage Booster 250 may be represented by element U4, whose output voltage VH can be, in one embodiment, as high as 16 volts. Use of element U4 may be used to keep the Motor power essentially constant, up to the point where the battery 120 is essentially fully drained. When the battery 120 is 6 volts and four 1.5 volt batteries are used, this point may be reached when each 1.5 volt battery cell is reduced to 0.8 volts.
However, before all the power in the battery 120 is used up, the original 6 volt total would have long since been reduced to 3.2 volts, well below the operating level of some or all of the elements of the apparatus. Accordingly, in an exemplary embodiment of the present invention, the Micro Controller U2, having access to the chip supply voltage (see V+ in
This process can repeat as often as necessary to maintain the voltage levels between an operable range (e.g., between about 4.5 volts and about 5.5 volts). This may insure continued operation of the PIR Controller 100 and the other elements, even when the voltage of the battery 120 falls to a low level (e.g., 3.2 volts).
In an exemplary embodiment of the present invention, an alarm is used to alert a user that the battery 120 needs to be replaced. The Micro Controller U2 can be configured to sense depletion of voltage of the battery 120 to some still viable level (e.g., 3.3 volts) and then enable transistor Q2 to activate a Piezoelectric Buzzer A1, whose audio can be heard outside the case of the apparatus.
The alarm can be used for other purposes, such as when the Micro Controller U2 (or 200) senses a condition that might affect performance. An example would be the development of very high friction in the lifting mechanism itself, which would cause an increase in the average Motor current required. This can be done by storing/memorizing the value of the Motor current when first installed, and comparing the most recent values after much usage has occurred.
As discussed above, the value N1 represents an amount of Motor current above which it can be inferred that the Motor M1 is about to stall. This value N1 can be derived by actual experience in each installation, in which the toilet Seat weight or friction can vary from a norm, and in which Battery depletion, if not remedied by the function described above, can be a factor in determining Stall current behavior. Accordingly, in an exemplary embodiment of the present invention, the Micro Controller U2 is configured to examine the actual measured Stall Current and derive a dynamic Stall Current Reference from the observed behavior.
Further, as discussed above, when Motor power is first turned on, the Motor M1 may require more current initially (e.g., a startup current) before reaching steady state operation. If the startup current too large, it may trigger the Stall Detection routine and stop Motor M1 rotation effectively before it even starts. Accordingly, in an exemplary embodiment of the present invention, the behavior of the Motor current is analyzed by the Micro Controller U2 to determine how long it takes for the Motor current to decline from the high Startup value to a normal Steady State value. The Micro Controller U2 then activates a Stall Sensor Time Delay, which for that amount of time after startup, may be used to prevent a false Stall Current value from prematurely shutting down operation of the Motor M1.
Referring back to
The top cover 205 of the case 200 is sealed (e.g., it may be welded). The top cover 205 may have a hole which provides an opening which is sealed by installation of a Fresnel Lens that focuses Infrared Radiation on the PIR Sensor. The Lens may be covered by a Plastic Infrared Filter Window 255, which also serves to seal the top cover 205 against the entry of water. The Motor 150 may be installed from an opening in the Base 210, which may be covered by a Plate and/or a cemented gasket. This gasket may be further held in place by the Seat Bolts, which force the entire assembly against the Toilet Bowl, again reinforcing the Seal against entry of water.
In a further embodiment, as shown in
In the embodiment shown in
However, torque needed to lift the toilet seat is not constant with its angle, but approximately co-sinusoidal, starting with a maximum force when the seat is horizontal, or down, and decreasing to Zero when the seat is vertical. For that reason, a means of providing such a transition of force is desirable. This objective can be obtained by the means described below, in conjunction with
Instead of sprockets and chains connecting the two Hubs as in
Note that the relative position of the bearings are such as that when the toilet seat 260 is down, the bearing 908 on the Spur gear Hub 903, is on the horizontal axis, while the bearing 909 on the Lever Shaft Hub 904, is on the vertical axis. Thus, when the driving Hub 903, is rotated counterclockwise by the Motor 150, the driven Hub 904, is in a position to apply maximum torque to its shaft, and the rotational speed will be low, due to the primary act of the Hub 903 is in the lifting phase, not the lowering phase. As the Motor 150 turns the Spur gear 902 counterclockwise at constant rotational velocity, and as the Seat 260 is lifted, Hub 904 transitions to positions of lower torque, consistent with the declining force need to lift the seat as it becomes more vertical, but of higher velocity. But, it eventually reaches a point where the two hubs 903 and 904 complete a 90 degree rotation, with the seat 260 now lifted to the vertical position, and where the stall sensor 146 will stop the motor 150, terminating the lifting phase. Accordingly, this configuration delivers its highest torque when it is needed to start lifting the seat from its initial horizontal position, and then increases the lifting velocity to complete the lifting cycle in a shorter time.
The PIR 1101 senses motion (e.g., from a waving hand) and outputs a signal corresponding to the sensed motion to the microcontroller 1102. The microcontroller 1102 analyzes that signal to determine whether the signal meets a starting criteria. If the starting criteria is met, the microcontroller 1102 sends an enable signal to the voltage booster 1103 to deliver a boosted voltage to the motor driving unit 1106. The microcontroller 1102 may periodically enable and disable the enable signal so that the booster 1103 delivers the voltage in an on-off duty cycle ratio such that the average voltage sets the motor speed 1105 to lift or lower the seat in a constant amount of time, independent of the weight of the seat or hinge friction (e.g., within 1 second). If conditions change, the device can be configured to adjust this average voltage to maintain constant lifting and lowering periods. When the seat has been lifted or lowered to its final destination, the current output by the motor 1105 to the microcontroller 1102 indicates a stall and the microcontroller 1102 stops enabling the voltage booster 1103 and disables the motor driving unit 1106.
The voltage booster 1103 is optional. When the voltage booster 1103 is not present, the battery 1104 provides power directly to the microcontroller 1102 and the motor driving unit 1106. Although not shown in
The microcontroller 1102 may contain a high frequency clock so that the counting of the clock pulses between any two events permits measurement of the time between events. The microcontroller 1102 starts a lift/lower cycle when it receives an acceptable signal from the PIR 1101 and stops the lift/lower cycle when it receives the stall signal. Thus, the time between the start and stop (e.g., a lifting period and/or a lowering period) can be measured precisely and stored within the microcontroller 1102 for making adjustments to the duty cycle. For example, suppose that is desired that the entire cycle (e.g., a single lifting or lowering period) should take 1 second. If the speed of the motor 1105 is controllable, it is possible to set the motor drive voltage so that its average speed during any lift or lowering cycle takes exactly the same amount of time. However, motor speed is dependent not only on the drive voltage, but also on the weight of the seat and hinge friction, which may change over time.
In an exemplary embodiment of the invention, the device has a dynamically adjusting motor drive voltage control to assure that the desired lift or lowering time is set and maintained, independent of the seat conditions. For example, the microcontroller 1102 may be configured to retain (store) a preset lifting and/or lowering period and count actual lifting and lowering periods, and on each lift or lowering cycle, the microcontroller 1102 can determine if the actual lifting or lowering period is shorter or longer than desired. If it is longer, the microcontroller 1102 can reduce the average voltage, and vice versa. As shown in
As shown in
In at least one embodiment, the On/Off duty cycle is repeated many times during the Lift/Lower Cycles, such that the ratio of On to Off meets the average voltage needed to meet the time requirement. In an alternate embodiment, the ratio of On to Off is varied so that near the end of the cycle the Off periods become more frequent than the On cycles. For example, one can increase the On to Off ratio at the beginning and middle of the cycle so as to maintain the correct average On to Off ratio. Accordingly, while the cycle time is maintained to the specified value, the lifting or lowering is slowed down near the end of the cycle, giving the seat a softer landing.
The slots 1151 and 1152 are open at one end so that the device may be slid under mounting bolts of a toilet seat assembly without removing the toilet seat from the toilet itself, which is accommodated by the thickness of the base 1150. For example, in at least one embodiment of the device, the base 1150 has a thickness of about ⅛ of an inch. In this way, merely loosening the bolts by turning the hand operated nuts permits the base 1150 to be slid under the seat assembly. Further, since the base 1150 is relatively thin, it allows the device to be installed without materially altering the angle of the toilet seat on the toilet, which helps to maintain the seat manufacturer's design intention. In at least one embodiment of the device, the base 1150 is made of stainless steel or corrosion protected carbon steel. The base 1150 may include four metal flat head screws 1153-1156 for mounting a gear case (not shown) to the base 1150. The gear case will be described in more detail below. The gear case may be mounted to the base in ways other than the screws (e.g., using less or more than the four screws or by an entirely different method).
The base 1150 may have an extension 1157. The extension 1157 may be somewhat rectangular in shape. In at least one embodiment of the invention, the outer case of the device (not shown), fits between the top edge of the base 1150 and the bottom edge of the extension 1157, and does not extend beyond the slots 1151 and 1152. The outer case will be discussed in more detail below.
The above described ferrules/clamp rings/screws may be used to tether the wire rope 1305 to deliver torque to the hub 1304 of the output shaft. The use of the wire rope 1305 may provide a step up in torque of over 3:1 and a like reduction in rotational speed.
The connection of the wire rope 1305 shown above transfers torque from the spur gear 1302 to the output shaft without the need for an extra gear. The required rotation of the pinion gear 1301 and spur gear 1302, associated with the full range of a toilet seat angle rotation, is less than around 180 degrees. Therefore a motor that has sufficient torque, and an internal gear mechanism that permits its output shaft to rotate at around 10 RPM, could couple directly to the spur gear 1302 and lift the seat 90 degrees in a few seconds, depending on the relative hub diameters.
Referring back to
As discussed above, the microcontroller 1102 analyzes signals it receives from the PIR sensor 1101 to determine whether to lift or lower the lever 1307. The PIR sensor 1101 may include one or more PIR sensors. For example, when a single PIR sensor is used, the seat may alternate between lifting and lowering each time the single sensor is triggered. Alternately, when two PIR sensors are used, the seat may be lifted when the first sensor followed by the second sensor are triggered in succession and lowered when the second sensor followed by the first sensor are triggered in succession.
In an exemplary embodiment of the invention, the microcontroller 1102 is programmed to stop lifting or lowering the seat when an obstruction is encountered, whether it be from the seat naturally reaching the end of its travel, or due to an internal or external obstruction caused by purposeful or accidental personal contact. After stopping the lifting or lowering, the microcontroller 1102 may resume lifting or lowering after a certain period of time has elapsed, or wait for another user command. In a further exemplary embodiment, the device includes an audio and/or a visual alarm and the microcontroller 1102 is programmed to sound the alarm when the microcontroller 1102 starts the seat lifting or lowering. In a further exemplary embodiment, the microcontroller 1102 is configured to use predefined preferences and automatically return the seat to a preferred position based on these preferences. For example, a user may prefer to have the seat always return to a down position when a predefined period of inactivity has elapsed after the seat has been lifted up.
In another exemplary embodiment, the microcontroller 1102 self adjusts seat drive control parameters, such as stall current level based on historical accumulation of operation, such as normal operating current, dependent on the seat's weight and operating friction. By doing this self-adjustment, it may preclude the need for setting or adjusting operating parameters by the installer, who may encounter a great variety of such parameters due to the variation in design and environments between different manufacturers and installation conditions.
In another exemplary embodiment, the microcontroller 1102 is programmed to perform automatic conditioning of a power duty cycle to all internal electronic components to assure minimum use of power, while still maintaining effective sensing of a command (e.g., initiated by hand movement) within the expected duration of such a command. For example, a 3:1 Off-On cycle for the PIR Sensor 1101 would be effective in saving power. In at least one embodiment of the invention, the ‘On’ time is set to at least 250 milliseconds, and the cycle repetition rate is set at 2 seconds or greater. The device may also be configured to include a manual control that allows a user to select among various performance options. In an exemplary embodiment, the manual control is accessible when the outer case 1250 is removed.
The device includes batteries, which provide power to the components therein (e.g., the microcontroller 1102, motor 1105, PIR sensor 1101, etc.). In an exemplary embodiment of the invention, the device includes an audio and/or visual alarm and the microcontroller 1102 is programmed to alert users that a replacement of the batteries is required or alert a user that a gross change in seat parameters has occurred (e.g., a change in rotational friction of the seat itself).
The battery case 1703 is removably connected to the gear box 1702 by lifting it off snaps 1705, which may be similar to those used on 9 volt batteries. The mates of the snaps 1705 are secured to the gear box 1702 (e.g., the drive system). This permits the batteries 1704 to be installed away from the toilet itself, or they could be provided as a pre-assembled snap in kit. In an alternative embodiment of the invention, the battery case 1703 is screwed down to the top of the gear box 1702, which is already firmly attached to the base 1150, and subsequently secured to the toilet seat itself.
Connection lines 1706 of the motor 1701, which lie below the battery case 1703, pass through the battery case 1703. The battery case 1703 provides direct pass-through connections, connecting to the motor 1701 leads via two of the snaps 1705, or by direct wiring to the pass-though wires if the battery case 1703 is screwed to the drive system. In this way, the motor wire connections are not exposed when the outer case 1250 is removed to replace the batteries 1704.
Further, the battery case 1703 plays a role in attaching the outer case 1250 to the gear box 1702. As shown in
The battery case 1703 includes a top battery case 1820 and a bottom battery case 1830. The outer case 1250 is attached to the upper battery case 1820 and the microcontroller 1102, and the lower battery case 1830 is attached to the gear case 1300 and the base 1150. Two locations on the battery cases 1820 and 1830 may include Neodymium magnets placed in opposing positions, at opposite ends of their structure. The magnets serve to apply a force directed to hold the battery cases 1820 and 1830 together; this force being transferred to the outer case 1250, also serving to force the outer case 1250 down to keep the entire assembly closed. The force of the magnets 1706 should exceed the opposing forces of the battery springs and the gasket 1200, which seals the outer case 1250 over the entire assembly. Thus, to remove the outer case 1250 to access the batteries 1706 for replacement, it is only necessary for the outer case 1250 to be gripped and pulled upwards. The battery cases 1820 and 1830 also provide contacts for the pass-through of the Motor connections, so that when the batteries 1706 are being replaced, no wires or other connections are encountered.
By adjusting a compression bolt/screw 1904 on the bottom of the clutch 1306, the normal force may be adjusted so that the clutch 1306 releases before a destructive torque is applied back to the gear assembly by inadvertent force applied to the toilet seat. The compression screw 1904 can be rotated to press firmly against the plug 1902 so as to increase its internal pressure to such a degree that normal force of the plug against the cylindrical circumference of the shaft 1903 produces a frictional torque sufficient to lift the seat, but less than is required to slip if an excessive external force is applied to the seat. This will prevent a torque higher than the motor 1701 can handle from being applied backwards, via the drive system, which might otherwise destroy the gears of the motor 1701. The plug 1902 completely surrounds the output shaft 1903, transmitting the pressure level created by the adjustment screw 1904 normally on all cylindrical surfaces of the shaft 1903 in contact with the plug 1902. This may assure stability of pressure adjustment, since there are no relief areas in which the plug 1902 could gradually expand into to change the calibration. The resultant friction force which the clutch 1306 could withstand at the point of release is the product of the friction factor of the plug 1902, multiplied by the area of contact between the plug 1902 and the output shaft 1903.
A compressive force may be applied against the plug 2101 through a set of washers 1905 (e.g., Belville, Clover Leaf, etc.) to stabilize the pressure of the plug 1902 so that it is a more controlled function of the screw rotation. The plug 1902 can be made from a combination of Polyoxymethylene plastic and other substances (e.g., polytetrafluoroethylene, which is known by the trade name of Teflon™) to adjust the friction factor. For example Delrin 150™ is a product made by the DuPont Corporation that has a coefficient of friction, against steel, of around 0.19. To develop a release torque of, say, 36 inches with a shaft diameter of 3/16″, would require a Delrin pressure of 400 psi, requiring the use of a set of 4 washers in series to create this pressure within the normal linear range of such springs less than ½ inch in diameter.
The Lever 1307 may be equipped with a tab 1907 made from polytetrafluoroethylene (e.g., Teflon). The device is installed under the existing seat assembly such that the tab 1907 rests against the bottom of the seat, allowing the relative position of the lever 1307 contact with the seat to slide, in response to any misalignment of the centers of rotation of the device and the seat itself. In at least one embodiment of the invention, the height of the device center of rotation is about 0.75 inches above the base 1100 to match the usual standard height of the seat center of rotation. In an exemplary embodiment of the invention, the lever 1307 is equipped with a magnet and a paste-on metal decal that automatically sticks to the underside of the seat. The decal assures that when the device is commanded to lower the seat, the seat will follow the lever 1307 in the downward direction, kept in contact by the attractive force of the magnet and the paste-on metal decal. The attractive force of the magnet to metal does not preclude sliding of the contact between them, since the magnetic force only has an influence on the friction of the contact, proportional to the normal force, slightly increased by the magnetic attraction.
In an alternate embodiment, contact between the seat and the lever 1307 can be maintained by an internal drive system stop, that prevents the seat from reaching a vertical angle greater than, for example, 70 to 80 degrees. This allows gravity to provide the force necessary to keep the seat and lever 1307 in contact as the lever 1307 is commanded to lower. In another alternate embodiment, a small flexible plastic lanyard is connected to the seat and the lever 1307 to assure that the seat follows the lever 1307 downward. The lanyard may be affixed to the bottom of the seat via a self contained sticky surface.
In at least one embodiment of the present invention, the case 1250 is sized to fit into a space of about 3.75 inches. The output shaft and the lever 1307 are not restricted from being in line with the seat center of rotation, which in at least one embodiment is about 0.375 inches behind the back of the seat, underneath which the lever 1307 extends. In at least one embodiment of the invention, the distance behind the seat center of rotation, that the water tank's front is located is about 2.5 inches. For example, in certain toilets, a case depth dimension larger than about 3 inches may encounter interference with the water tank, preventing its installation. In at least one embodiment of the invention, the device is within the plan view dimensions of 3.75 by 3 inches. In at least one exemplary embodiment of the invention, the height of the device is 5 inches or less.
It is desirable that the outer case 1250 of the device have no openings of any kind that would permit the entry of liquid into the interior, which could compromise the integrity of the electronic components, the batteries, the motor, and the gear mechanism. Normally, in devices which utilize PIR sensing to activate their function, a window is provided to allow entry of IR signals at very low attenuation. Such windows are normally sealed, but not completely impervious to liquids. Further, light entering the window may be attenuated. Fresnel lenses are thin enough to fit into the location between the outer case 1250 and the PIR sensor 1101. However, an independent element such as a conventional Fresnel lens, presents two additional surfaces which cause reflection of such energy, the internal surface of the case and the upper surface of the Fresnel lens. According to an exemplary embodiment of the invention, this loss of signal can be avoided by designing a Fresnel lens that is embossed onto the internal surface of the case 1250.
Since high resolution imaging is not necessary, which is normally the function of a Fresnel lens, it is only necessary to focus as much of this energy as possible on the IR sensing element. Accordingly, the lens designed to be embossed on the internal surface of the case can be of a low resolution, so long as its dispersion is of an order of magnitude of the width of the sensitive portion of the IR sensor. This reduces the number of Fresnel segments needed in the lens.
In at least one exemplary embodiment of the invention, the lens 2350 is located in the geometric center of the top wall of the outer case 1250. In at least one embodiment of the invention, the diameter of the lens 2350 is about 0.75 inches. The outer case 1250 having the top surface embossed with the lens 2350 may be made by using a mold having a corresponding surface with flat portions for regions surrounding the lens and segment portions corresponding to the segments of the lens. The focus point of the 2350 may be concentrated on the region of space directly above the device and its internal sensor, which requires the user to wave an object (e.g., their hand) above this space to activate operation. Without this focused region, any casual movement by a person near or on the toilet could accidentally activate the lifting or lowering function.
However, the lens 2350 may be embodied in various other ways, as the above Table 1 merely provides one example of how the lens could be implemented. Referring to Table 1, the radius column lists a distance from the center of the lens 2350 along line A-A′, and assuming a cut is present at the listed radius, the angle column lists the angle of the cut, dept column lists the dept of the cut, and the net depth lists the net depth of the cut.
Please note that use of a spur gear and pinion gear as described above is merely an example, and the invention is not limited to use of any particular gear type or gear type combination. For example, whenever a spur gear is used above, it could be replaced with various other types of gears (e.g., a pinion gear), and whenever a pinion gear is used above, it could be replaced with various other types of gears (e.g., a spur gear).
In at least one embodiment of the invention, the microcontroller 2702 can automatically adjust the upper and lower PIR signal detection limits of the PIR sensor 1101 to maintain the original level of each relative to the voltage of the 1104 battery as it may change due to depletion.
In at least one embodiment of the invention, an object with a pattern of holes (e.g., slits) that allow the passage of light (or infrared light) is waved in front of the PIR sensor 1101 to program the microcontroller 2702. For example, the signal generated by the PIR sensor 1101 in response to receipt of light through the different patterns can be interpreted by the microcontroller 2702 as different programming commands. In an alternate embodiment, the microcontroller 2702 includes an infrared receiver that is configured to receive these commands as infrared commands or flashes. The commands may be used to place the device into an installation mode (e.g., a run mode) or a calibration mode, and to program the device during the calibration mode.
When the microcontroller 2702 receives the signal from the amplifier 2701 that commands it to lift or lower the toilet seat assembly, the microcontroller 2702 can start a timer and sound an audible beep. The microcontroller 2702 can delay the lifting or lowering for a pre-defined start-up delay to avoid a premature stall. After this delay, the microcontroller 2702 can apply a command (e.g., a direction signal) to the motor driver 1106 to rotate the motor 1105 and turn on the voltage booster 1103. The microcontroller 2702 can start a PWM cycle routine stored within the microcontroller 2702, which applies a power control signal to the motor driver 1106 to cycle power on and off to the motor 1105 with a variable duty cycle. The above commands may include a calibration command that changes the duty cycle to a new value.
The routine can run the motor 1105 at such a speed that it completes its cycle within a pre-programmed time interval (e.g., about 1 second). The above commands may include a calibration command that changes the pre-programmed time interval to a new value.
The routine can slow the motor 1105 down before the end of the cycle to provide a ‘soft’ landing for the toilet seat. The routine can be used to maintain a constant motor speed before the soft landing period despite variations in the load torque, as measured by variations in the current of the motor 1105.
The microcontroller 2702 can examine the stall current received from the motor 105 and control the motor controller 1106 to shut off power to the motor 1105 at the End of a Cycle (EOC), according to a combination of signal level and a rate of signal level change, using a slew analysis routine. The slew analysis routine may be configured to minimize noise effects.
The microcontroller 2702 can mark the time from start to EOC, and alter the routine to either speed up the next cycle, or slow it down to maintain a preset cycle time despite changes in toilet seat hinge friction or other causes. The above commands may include a calibration command that changes the preset cycle time to a new value.
The microcontroller 2702 can mark the stop time and disable a restart of directing the seat downward for a first period time (e.g., around 90 seconds) and disable a restart of directing the seat upward for a second period of time (e.g., for around 60 seconds). The above commands may include a calibration command that changes the first and second periods to new values.
If the seat is in the up position, the microcontroller 2702 can start a timer clock so that at the end of the pre-programmed interval, the seat will automatically return to the down position. The microcontroller 2702 may sound an audible beep before automatically returning the seat.
The microcontroller 2702 may determine a premature stall current signal, when the seat is touched after it starts to lift or lower. For example, a user could have used their hand to stop the seat while it is motion. When the microcontroller 2702 determines the stall current signal, it can control the motor controller 1106 to stop the motor 1105 from lifting or lowering the seat before it can inflict injury and then return to the seat to its original position. The microcontroller 2702 may sound an audible beep before returning the seat. The microcontroller 2702 may be configured to ignore a premature lift or lower when adjusting the speed of the motor 1105.
The microcontroller 2702 can monitor the battery 1104 and the voltage booster 1103 output voltage and signal to determine if either is reduced below a pre-defined value for each. The microcontroller 2702 can sound an audible beep when either of these signals is close to approaching the pre-defined values.
The microcontroller 2702 may include memory that retains the last value of variables used for its routines/functions even when the battery 1104 has been disconnected. These values may be restored when the battery 1104 is reconnected. The device may include a visible LED that is used to identify the position of the device (e.g., in a dark bathroom). The LED may blink at a pre-defined rate.
In an exemplary embodiment of the invention, the lever 2804 is affixed to the toilet seat assembly. In this embodiment, the lever 2804 is not connected to the seat by some flexible tether or magnetic means, but is screwed directly to the underside of the new toilet seat. As such, the center of rotation of this all-in one assembly is the output shaft 2806, as there are no hinges on the toilet seat. In addition, installation of the assembly is done in exactly the same manner as installing a typically toilet seat, which is performed by aligning the mounting assembly with the holes provided in the toilet itself.
As described with respect to
When the spiral spring 1310 is located on the spur shaft 1311, the wire rope 1305 or another coupling mechanism between the spur shaft 1311 and the output shaft is used to provide the full torque necessary to lift the seat. Accordingly, the wire rope 1305 needs to be very strong and flexible. For example, Sava Industries™ provides a wire rope that can be used.
However, if the spiral spring 1310 is instead located on the driver shaft (see hub 1304), the burden on the wire rope 1305 can be reduced to only the force needed to overcome friction. In at least one embodiment of the invention, the diameter of the spiral spring is limited to about ¾ inches, when the center of rotation of the drive shaft is brought as close to full alignment with the center of rotation of the seat hinges. Thus, using a larger spiral spring at this location would prevent such a close alignment due to physical interference. Further, any mismatch between the torque provided by the drive shaft would require the motor 1105 and the wire rope 1305 to provide the difference in torque. Accordingly, it would be useful to be able to match the spring torque of the spiral spring 1310 to the seat load torque. However, as a practical matter, it is difficult to obtain the springs needed to match one of the wired varieties of loads presented by seats manufactured by different companies.
Thus, in an exemplary embodiment of the invention, a series of spiral springs are provided, where each has a binary relationship of torque, but is identical or similar in shape to enable side by side mounting. In this way, the combination of springs can be selected to match the particular load that a given application presents.
Since all of the springs 3001 may be of the same shape, it is possible to mount them such that the outer tang 3003 of all the springs 3001 simultaneously engage a movable detent 3004 disposed on a lead screw 3005. When the output shaft 2806 is rotated clockwise, the outer tang 3003 comes into contact with the detent 3004, which prevents the springs 3001 from rotating any further. Accordingly, the inner tang 3002 now tensions the springs 3001 causing a counterclockwise torque to develop that is proportional to the further rotation of the drive shaft 2806. When the lever 2804 is rotated clockwise, the seat is also lowered, increasing the force of gravity to assist the drive shaft 2806 in tensioning the springs 3001, thereby storing its potential energy to assist the drive shaft 2806 in raising the seat when that occasion arises.
The amount of reverse torque provided by the springs 3001 when the seat is fully lowered, and ready to be lifted, is proportional to the amount of rotation which the springs were subject to when the drive shaft 2806 rotated clockwise. The tensioning of the springs 3001 does not start until the outer tangs 3003 come into contact with the detent 3004.
The detent 3004 is movable forward and back by means of the lead screw 3005. By rotating the lead screw 3005, whose threads engage threads in the detent 3004, the position of the detent 3004 is adjusted forward and back, either increasing or decreasing the angle of the output shaft 2806 where the outer tangs 3003 will encounter the detent 3004. Thus, by positioning the detent 3004, it is possible to either increase or decrease the spring torque by the amount of pre-stress applied to the springs 3001.
A proper adjustment of the detent 3004 position will be that where the amount of tension results in the minimum torque that the drive shaft 2806 has to provide in lifting the seat anywhere in the 90 degree rotation required to lift the seat from its down position to its up position. In general, since the restorative force provided by the springs 3001 is essentially linear with rotation, and the downward force due to gravity acting on the seat is cosinusoidal, a maximum torque results from adjusting the detent 3004 so that there is tensioning of the springs 3001 before the drive shaft 2806 starts to rotate clockwise.
Further, by locating the springs 3001 on the drive shaft 2806, this direct connection may assure angular alignment of the spring's restorative force with the gravitationally derived torque of the seat.
As shown in
Rotation of the hub of the spur gear 3101 will transfer to the hub of the drive shaft 2806 by either pulling or pushing, dependent on the direction of rotation of the shaft of the spur gear 3101. The pinion gear 3102 is driven by the motor 1105. The spur gear 3101 may be at the maximum clockwise position, so that rotating the pinion gear 3102 counterclockwise will rotate the spur gear 3101 clockwise. This moves the crank rod 3105 to the right, rotating the drive shaft 2806 counterclockwise also. The lever 2804, which is attached to the drive shaft 2806 is then in the down position, and is rotated to the up position when the drive shaft 2806 is rotated 90 degrees counter clockwise. Accordingly, since the lever 2804 is under the seat, the seat is lifted from the down position to the up position. To lower the seat, the motor 1105 reverses, which results in an opposite operating direction of all gears, shafts, and the lever 2804.
The use of the crank axles 3104 and the crank rod 3105 permit the shafts of the pinion gear 3102 and the spur gear 3101 to be made of a strong moldable plastic such as Delrin. Further, the gears may be made by either machining from stock or by injection molding.
Although the illustrative embodiments have been described herein with reference to the accompanying drawings, it is to be understood that the present invention is not limited to those precise embodiments, and that various other changes and modifications may be affected therein by one of ordinary skill in the related art without departing from the scope or spirit of the invention. All such changes and modifications are intended to be included within the scope of the disclosure.
This application is a Continuation-in Part of U.S. application Ser. No. 12/945,224 filed on Nov. 12, 2010, which is a Continuation-in Part of U.S. application Ser. No. 12/557,071 filed on Sep. 10, 2009 and issued as U.S. Pat. No. 7,917,973; the disclosures of each are incorporated by reference in their entirety herein.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 12945224 | Nov 2010 | US |
| Child | 13397880 | US | |
| Parent | 12557071 | Sep 2009 | US |
| Child | 12945224 | US |
