The present invention relates to automatic dishwashing machines (dishwashers) and in particular to dishwashers providing automatic dispensing of washing aid over successive washing sessions.
Dishwashers, such as those found in many homes, provide a wash cavity holding one or more racks into which dishes, flatware, and the like may be placed for cleaning. The wash cavity may be sealed by a door opening at the front of the wash cavity to allow loading and unloading of the cavity but then closed during a washing cycle to prevent the escape of water sprayed within the volume of the wash cavity. Upon completion of the washing cycle, a drying cycle is initiated during which water is drained from the wash cavity and moist air is discharged through a vent or the like.
A washing session may include a pre-wash portion in which the dishes are rinsed with or without the application of detergent. Accordingly, most dishwashers provide for automatic detergent dispensing, for example, from an in-door dispenser, that can be automatically triggered at a later time than the wash cycle begins. A separate dispenser may provide an actuator for dispensing a rinse-aid, typically during the rinse cycle, such as assists in drying of the dishes and reduces water spotting.
An electrical solenoid may be used in the dispenser to activate mechanisms releasing detergent and rinse-aid. Typically, a single electrical solenoid operates to simultaneously dispense detergent and rinse-aid thereby reducing complexity and cost of the dispenser. At a time when detergent should be dispensed, the solenoid operates briefly to release a spring-loaded door covering a chamber holding the detergent while also dispensing a small amount of rinse-aid. This small amount of dispensed rinse-aid is an accommodation to the use of a single actuator.
At a time when rinse-aid should be dispensed, the spring-loaded door containing the detergent has already been opened and the detergent fully dispensed; accordingly the solenoid may be operated over a length of time necessary to release operative amounts of rinse-aid without concern about the detergent dispenser.
The rapid motion of an electrical solenoid can create substantial noise. In addition an electrical solenoid may consume significant electrical power when operated for an extended duration during the dispensing of rinse-aid. Slower, relatively quiet actuators such as wax motors and bimetallic elements can significantly reduce the actuation noise of the dispenser but may be insufficiently fast in response to allow a single actuator to release the detergent door while minimizing undesired dispensing of the rinse-aid. Wax motors and bimetallic elements, like solenoids, consume power while actuated.
The present invention provides an automatic washing aid dispenser employing a low-voltage DC motor to dispense both detergent and rinse-aid with reduced noise. A gear train and position sensing system allows electrical power to be used only during transition between states and not during actuation time during which the motor may be deactivated. In one embodiment, the invention allows independent dispensing of detergent and rinse-aid eliminating waste of rinse-aid as well as the noise generated during a high-speed, short duration actuation.
Specifically, the invention provides a wash-aid dispenser for dishwashers having a rinse-aid reservoir adapted to hold a liquid rinse-aid and including a valve for dispensing a rinse-aid from the reservoir into the dishwasher and having a detergent chamber adapted to hold dishwasher detergent and including a door openable to dispense the detergent from the detergent chamber. An electric actuator comprising a DC electric motor and gear reducer provides an actuation output communicating with both the valve and door to dispense rinse-aid and detergent with operation of the DC electric motor.
It is thus a feature of at least one embodiment of the invention to provide a low noise actuator that can operate both the rinse-aid dispenser and the determent dispenser with low energy consumption.
The wash-aid dispenser may further include a sensor sensing the position of the actuation output.
It is thus a feature of at least one embodiment of the invention to permit closed-loop control of the actuator output to permit multiple states of actuator output to be generated, for example, more than two states with a single polarity motor drive, and typically more than three states.
The actuation output is movable between a first position actuating only the door of the detergent chamber, a second position actuating only the valve of the rinse-aid reservoir and a third position actuating neither the door of the detergent chamber nor the valve of the rinse-aid reservoir.
It is thus a feature of at least one embodiment of the invention to permit separate activation of the detergent chamber and rinse-aid reservoir to eliminate rinse-aid waste.
The sensor may provide a sensor output distinguishing among the first, second, and third positions.
It is thus a feature of at least one embodiment of the invention to permit the control system to readily distinguish between the three activation states without precise timing.
The sensor may further provide a sensor output distinguishing a fourth position actuating neither the door of the detergent chamber nor the valve of the rinse-aid reservoir immediately after actuation of the rinse-aid reservoir and wherein the third position is an actuation of neither the door of the detergent chamber nor the valve of the rinse-aid reservoir immediately after actuation of the door of the detergent chamber.
It is thus a feature of at least one embodiment of the invention to permit the rinse-aid dispenser to stop for an arbitrary period of time in between each state of dispensing to provide truly independent dispensing.
The sensor may further provide an output distinguishing a fifth position indicating a closing of the valve of the rinse-aid reservoir and wherein the second position is an opening of the valve of the rinse-aid reservoir.
It is thus a feature of at least one embodiment of the invention to provide a positive indication of rinse aid valve closure for more reliable operation permit.
The gear reducer may include at least one gear providing a first cam surface and a follower activating an electrical contact to form the sensor. In addition or alternatively the gear may further provide a second cam surface actuating the valve of the rinse-and-reservoir. In addition or alternatively the gear may further provide a third cam surface actuating the door of the detergent chamber.
It is thus a feature of at least one embodiment of the invention to provide a simple mechanism by using a highly speed-reduced gear to provide independent high-resolution control of rinse-aid dispensing and detergent dispensing as well as signaling to the controller for control of the rinse-aid dispensing and detergent dispensing.
The gear train may include a worm gear attached to a shaft of the DC motor communicating with a set of at least two inter-engaging helical gear pairs providing a reduction of speed.
It is thus a feature of at least one embodiment of the invention to provide an extremely low profile dispenser suitable for use with typical dishwasher doors by extending the axis of the motor perpendicularly to the gear train.
The door of the detergent chamber may be spring-loaded to open upon actuation to be opened but not closed by the actuation output, and the valve of the rinse-aid chamber is both openable and closable by the actuation output.
It is thus a feature of at least one embodiment of the invention to eliminate the need for the DC motor to provide power for opening the door thus reducing the power requirement of the DC motor and eliminating mechanical binding problems if the door is blocked by cutlery or dishes or detergent encrustation.
The wash-aid dispenser may be adapted to mount to a dishwasher door hingeably movable between a horizontal and vertical position and may further include a fill-port communicating with the rinse-aid chamber for the introduction of rinse-aid into the rinse-aid chamber, and the fill-port may provide an entrance channel directed upward when a door on which the rinse wash-aid dispenser is attached is in the vertical position.
It is thus a feature of at least one embodiment of the invention to provide a fill-port that naturally resists inflow of wash water during use without the need for a cap that must be removed by the consumer and such as may be misplaced or dropped into the dishwasher.
The fill-port may be behind the door of the detergent chamber when the door of the detergent chamber is in the opened position.
It is thus a feature of at least one embodiment of the invention to limit the direction of water impinging on the fill-post during a majority of the cleaning cycle to maximize the effectiveness of the fill-port entrance channel.
The wash-aid dispenser may further include an enclosed channel extending along an upper wall of the detergent chamber to be covered by the door of the detergent chamber when the door of the detergent chambers in the closed position and to cooperate with the door of the detergent chamber when the door of the detergent chambers in the opened position to funnel water along the inner surface of the door of the detergent chamber into the enclosed channel to a rear wall of the detergent chamber to flush detergent from the detergent chamber.
It is thus a feature of at least one embodiment of the invention to positively conduct water fully to the rear of the detergent chamber to flush the detergent chamber without the risk of premature wetting of the detergent from distributed spray prior to full discharge.
The door of the detergent chamber in the opened position may provide a conduit between the door of the detergent chamber and a body portion of the wash-aid dispenser receiving water from the dishwasher during a washing cycle.
It is thus a feature of at least one embodiment of the invention to positively fennel water into the detergent chamber by using the door as a conduit.
The wash-aid dispenser maybe adapted to mount to a dishwasher door hingeably movable between a horizontal and vertical position and may farther include an optical sensor positioned to detect a height of rinse-aid in the rinse-aid chamber below an identical single predetermined volume both when the door is in the horizontal and in the vertical position.
It is thus a feature of at least one embodiment of the invention to permit accurate measurement of rinse-aid both when the consumer is filling the rinse-aid reservoir and when the door is in the upright position in preparation for or during washing.
The wash-aid dispenser may further include a first and second optical sensor position to detect a height of the rinse-aid in the rinse chamber below a single predetermined first volume and above a second predetermined volume and further including an indicator indicating to a user both conditions of the rinse-aid in the rinse chamber being below the first volume and alternatively above the second volume.
It is thus a feature of at least one embodiment of the invention to provide the user with guidance not only as to when to fill the rinse-aid chamber but to also prevent over filling of the rinse-aid chamber such as may waste rinse-aid.
These particular features and advantages may apply to only some embodiments falling within the claims and thus do not define the scope of the invention.
Referring how to
In the sealed position, the inner surface of the dishwasher door 8 is exposed to the wash cavity 12 and may support a washing aid dispenser 20 on the inner surface of the dishwasher door 18 to dispense washing aids directly into the wash cavity 12. The washing aid dispenser 20 includes both a detergent chamber 22 and a rinse-aid reservoir 24 to allow dispensing of two different wash-aids. When the dishwasher door 18 is in the open horizontal position, the washing aid dispenser 20 is accessible to the user for refilling the detergent chamber 22 and rinse-aid reservoir 24 with detergent and rinse-aid, respectively, as will be discussed.
A controller 15, for example, providing an electronic microprocessor communicating with a memory holding a stored program, may communicate with the standard electrical components of the dishwasher 10 including water pumps, heaters and valves (not shown) to control them according to stored program wash cycles selectable by the user. In conjunction with these wash cycles, the controller 15 may control the washing aid dispenser 20 for the dispersing of detergent and rinse-aid. In this regard, the controller 15 will provide electrical signals to the washing aid dispenser 20 and respond to electrical signals from the washing aid dispense 20 as will be discussed below.
Referring now to
Referring now to
The rinse-aid reservoir 24 may be filled with a liquid rinse-aid 28 which may communicate through a conduit 33 to a valve 21 dispensing the rinse-aid 28 through an outlet 26 (
Referring now to
The drive gear 40 may be driven by a speed-reducing helical gear train 43, the first gear of which is driven along its outer toothed periphery by a worm gear 44 engaging the teeth of the first gear of the speed-reducing gear train 43 and driven in turn by a low-voltage DC motor 46, for example, operating at a voltage of less than six volts and desirably less than five volts. The worn gear 44 allows the shaft and longest extent of the motor 46 to be positioned in a plane parallel to the plane of the inner surface of the dishwasher door 18 for reduced housing thickness of the washing aid dispenser 20. The present inventors have determined that a low power DC motor 46 may be used in this capacity, eliminating the need for large-gauge wiring and/or high voltages required by other actuator types as is possible through the use of the speed-reducing gear train 43 such as permits the necessary energy needed for dispensing to be obtained at lower power over a period of time rather than instantaneously as would be required for a solenoid or the like.
Referring now to
In contrast, the sensor cam 48 provides three reduced diameter sections 54a, 54b and 54c that cooperate with a cam follower arm 56 to press an electrical switch 58 three times during each revolution of the final drive gear 40 as these reduced diameter locations. These three times that, the electrical switch 58 is pressed (closed) include: during release of the dispenses door 23 and before and after dispensing of the rinse-aid.
Referring now to
At a later time, the motor 46 may again be activated by the controller 15 according to a predefined washing cycle to move the final drive gear 40 to position P3. Here the cam track 38 serves to dispense rinse-aid 28 by opening the valve 21. At this time, the sensor cam 48 closes the switch 58 again at time P4 indicating a start of the dispensing of rinse-aid 28. The controller 15 may continue operation of the DC motor 46 to ensure consistent full opening of the valve 21 until the sensor cam 48 opens a switch 58 indicating that the valve 21 is fully open. At this time, the controller 15 may stop electrical power to the DC motor 46 to conserve power and to provide an arbitrary dispensing time of rinse-aid 28.
When a predetermined amount of time has passed consistent with the dispensing of rinse-aid 28 in an operative amount, the DC motor 46 may again be activated by the controller 15 moving the final drive gear 40 to position P5 indicating closure of the valve 21 and the conclusion of the dispensing of rinse-aid 28. At position P5, and the switch 58 is closed, again to signal to the controller 15 that it may stop the motor 46 by the controller 15 for the conclusion of the wash cycle or until an additional dispensing of rinse-aid 28 may be desired. It will be appreciated that after this point, subsequent, rotations of the final drive gear 40 can be used to dispense additional rinse-aid “shots” independent of further dispensing of detergent which is substantially completely dispensed at time P4.
Referring now also to
Significantly, when the door opens, detergent 27 is released into the wash, cavity 12 and the dispenser door 23 becomes, a conduit for water 64 received on the top of the washing aid dispenser 20 and channeled downward between the inner surface of the dispenser door 23 and the outer surface of the body 29 of the washing aid dispenser 20. At the bottom of the dispenser door 23, a rearward elastomeric seal 67 on the dispenser door 23 connects to a front edge of a rearwardly extending false ceiling 66 of the detergent chamber 22 toward the back of the detergent chamber 22 where the channel opens releasing water to flush out any remaining detergent 27, an action promoted by a sharply downward sloping lower floor of the detergent chamber 22. As shown in
Referring now also to
Referring now to
Control of the indicator light assembly 75 may be provided by a control circuit 80 operating to provide electrical power to light emitting diodes 81a and 81b associated with prisms 82a and 82b passing through walls of the rinse-aid reservoir 24, the latter positioned to detect the level of rinse-aid 28. In particular, each prism 82 receives light from the respective light emitting diode 81 outside of the rinse-aid reservoir 24 directed toward a first 45-degree face of the prism 82 facing a second 45-degree face of the prism inside of the rinse-aid reservoir 24. These two opposed faces return the light along a parallel path to that emitted by light emitting diodes 81 to be received by respective light sensors 83a or 83b in the absence of rinse-aid contacting the faces of the prism 82. This is shown generally with respect to prism 82a being above a fill level 84 of rinse-aid 28 and results front the markedly different index of refraction between the material of the prism 82 and air in contact with the faces of the prism 82. In contrast, and with reference to prism 82b, the index of refraction of the material the prism 82 may be close to that of rinse-aid 28 causing light from light emitting diode 81b to be conducted into the rinse-aid 28 and relatively low amounts of light returned to the light sensor 83b. In this way, the control circuit 80 can detect the presence or absence of rinse-aid 28 covering the prisms 82 and can respond using a simple logic circuit to light lamp 77a if the signal from sensor 83a is below a predetermined threshold indicating the presence of rinse-aid 28 and to light red lamp 77b if the signal from sensor 83b is above a predetermined threshold indicating that no rinse-aid is covering prism 82b.
Generally prism 82b may be positioned to provide a signal determining whether the rinse-aid is above 25 percent of the volume of the rinse-aid reservoir 24 and prism 82a may be positioned to provide a signal, indicating whether the rinse-aid is below 75 percent of the volume of the rinse-aid reservoir 24. In this way the consumer may be encouraged not to overfill the rinse-aid reservoir 24 nor allow the rinse-aid reservoir 24 to be under filled.
Referring now to
Various features of the invention are set forth in the following claims. It should be understood that the invention is not limited in its application to the details of construction and arrangements of the components set forth herein. The invention is capable of other embodiments and of being practiced or carried out in various ways. Variations and modifications of the foregoing are within the scope of the present invention. It also being understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute various alternate aspects of the present invention. The embodiments described herein explain the best modes known for practicing the invention and will enable others skilled in the art to utilize the invention.
The present application claims the benefit of U.S. provisional application 62/343,959 filed Jun. 1, 2016 and hereby incorporated by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/US2017/030537 | 5/2/2017 | WO | 00 |
Publishing Document | Publishing Date | Country | Kind |
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WO2017/209882 | 12/7/2017 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
2832366 | Farison | Apr 1958 | A |
2973769 | Jacobs | Mar 1961 | A |
4488666 | Herbst | Dec 1984 | A |
6098646 | Hennemann | Aug 2000 | A |
20020153029 | Cerruti | Oct 2002 | A1 |
20030188768 | Cerruti | Oct 2003 | A1 |
20090145922 | Cerruti | Jun 2009 | A1 |
20090235962 | Classen | Sep 2009 | A1 |
20100161143 | Smith | Jun 2010 | A1 |
20120125366 | Beshears, Jr | May 2012 | A1 |
20160143506 | Van Tol | May 2016 | A1 |
20160220094 | Durham | Aug 2016 | A1 |
20170319044 | Szalas | Nov 2017 | A1 |
Number | Date | Country |
---|---|---|
101005788 | Jul 2007 | CN |
102892346 | Jan 2013 | CN |
105283111 | Jan 2016 | CN |
102013101157 | Aug 2014 | DE |
0457137 | Nov 1991 | EP |
0860141 | Aug 1998 | EP |
0602572 | Jul 2002 | EP |
2532667 | Mar 1984 | FR |
2014102369 | Jul 2014 | WO |
Entry |
---|
Merriam-Webster, (n.d.). Actuate. In Merriam-Webster.com dictionary. Retrieved Sep. 15, 2020, from https://www.merriam-webster.com/dictionary/actuate (Year: 2020). |
International Search Report for PCT/US2017/030537. |
Number | Date | Country | |
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20190125160 A1 | May 2019 | US |
Number | Date | Country | |
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62343959 | Jun 2016 | US |