Patent Application
20110047814
The present disclosure relates to a dryer (or drying) drawer. More particularly, the present disclosure relates to drying drawers employing circulating drying air through the drawer.
Traditionally, dryers use very high wattage heaters and open ducts to allow the free flow of air to remove water from clothing articles. Clothing is tumbled during this process which can cause garment wear. Also, the traditional drying process is not conducive for shoes and other bulky items. The problem solved is to drastically reduce the time required to dry articles of clothing et al., while minimizing the energy required to complete the drying cycle.
The use of drawer type dryers or compartment dryers can be particularly effective for woolens and delicate items (i.e. sweaters) which are not well suited for drying by conventional tumble dryers. In addition, other clothing items not well suited for tumbling, i.e. shoes, gloves, etc., can also effectively be dried with a drying drawer. Also, in locations where energy is at a premium, drying drawers can be more energy efficient than conventional dryers. In drying drawers, the clothes can be placed or positioned on a support rack. The drying drawers can simply circulate outside air through the cabinet in cases where the outside air is relatively dry. Heaters may also be used to heat the air supplied to the drying drawer. In still other embodiments, air is at least partially recirculated through the drawer while moisture is removed from the recirculating air so as to maintain a supply of drying air and to reduce the remaining moisture content (RMC) of the articles therein.
In one aspect of the present disclosure, a dryer drawer system is provided comprising a generally multisided drying chamber having opposed side walls, a rear wall, and at least one access door, wherein the door is sealable to the chamber. The system further provides a heater for increasing the temperature of the air in the chamber to evaporate moisture from the articles in the chamber; a sensor for sensing the temperature of the air in the chamber, at least one fan for circulating air in or through the chamber; a damper controlled air inlet connected with the multisided drying chamber; and, a damper controlled air outlet connected with the multisided drying chamber. Air flow through the chamber is provided in a first operational mode when the inlet and outlet are opened and a recirculating air flow is provided within the chamber in a second operational mode when the inlet and outlet are closed. The controller selectively switches between the first and second operational modes as a function of the sensed temperature in the chamber.
In another aspect of the present disclosure, a dryer drawer is provided comprising a generally multisided drying chamber having opposed side walls, a rear wall, and at least one access door. The drying chamber further includes an air inlet and an air outlet. A sensor is provided for measuring temperature in the chamber. The multisided drying chamber includes an air flow through the chamber in a first operational mode when the chamber is at a first temperature. The multisided drying chamber includes a recirculating air flow within the chamber in a second operational mode when the chamber is at a second temperature. A heater is provided for heating the air circulating in the chamber to evaporate moisture from articles in the chamber, wherein the heater alternates between on for the first operational mode and off for the second operational mode.
In still a further aspect of the present disclosure, a method of drying articles is provided comprising heating a drying chamber with a heater, wherein the chamber includes a generally multisided drying drawer having opposed side walls, a rear wall, and at least one access door. The method further comprises exhausting air from the drawer through an air outlet including a first damper for selectively opening and closing the air outlet, and drawing air into the drawer through an air inlet including a second damper for selectively opening and closing the air inlet. The method further comprises measuring a temperature in the drawer, streaming air through the drawer in a first operational mode when the first damper and the second damper are opened, recirculating air within the drawer in a second operational mode when the first damper and the second damper are closed, and switching in a series of cycle durations from the first operational mode to the second operational mode when a first predetermined criteria is reached and from the second operational mode to the first operational mode when a second predetermined criteria is reached.
In accordance with the disclosure, and as is best seen in
To be described in more detail hereinafter, the drawer 30 can include an automatic end of cycle detector based upon a predetermined criteria, for example, remaining moisture content (RMC) of clothing C or other articles therein which can be related to the decreasing time between temperature peaks. A ramp up damper cycling algorithm can be used to release moist air early during ramp up of a heat cycle in order to reduce time to reach a maximum temperature set point for drying. In addition, a current sensing circuit can be used to disable a heater 80 when additional loads are plugged in the unit to prevent tripping a circuit breaker. In conjunction with the damper cycling algorithm, a dual acting damper cycling process can simultaneously power at least two dampers 70, 72 to release moist air 73 while bringing in fresh non-moist air 71 into the system. Closing of a recirculation air path when drawing fresh outside air through the use of the dual acting damper facilitates the damper cycling and drying efficiency.
The drying compartment 10 further provides for a controlled air return path for preventing of short circuiting/bypassing of the system air flow through the use of baffling 60, 61 in order to force return air to flow to the front of, and around, an interior basket 90 (to be described hereinafter). A generally planar partition 100 can extend beneath basket 90 from front wall 34 to the fan supporting partition 35. Partition 100 can be spaced from bottom wall 14, to provide a return air flow path for air to return to the fan inlet area 46 when operating in the recirculating mode, and to serve as a drip shield. An opening 101 which may be an elongated gap or a plurality of slots or holes in partition 100, is provided proximate where the partition 100 meets front wall 34, to enable recirculating air to enter the space beneath the partition and return to fan inlet area 46. Partition 100 can be made of a material to lower the thermal mass of the system, wherein a lower overall thermal mass within the system aids in faster ramp up time to reach a predetermined temperature. The recirculating air path back to the fan inlet area is completed through opening 45 formed in the horizontally extending portion of the fan supporting partition 35.
As hereinbefore described, the partition or drip shield 100 separates areas within the drying chamber between a low pressure side and a high pressure side with respect to the fan 48. The material for the drip shield 100 can be selected from the group consisting of plastic, glass, and metal and can also comprise a heat source (not illustrated) for generating local heat, i.e. conductively, radiatively, convectively, etc., to the clothing articles C proximal to the shield. The drip shield 100 can also include perforations (not shown) for enhancing the circulation of air through and around the chamber. A mounting mechanism can be used to prevent unit tip over through the use of, for example, wall mounting brackets 110 and/or unit to unit mounting brackets 112. The above described elements reduce drying time, lower energy consumption, increase consumer convenience, and enable drying of articles not particularly suited for tumble drying (i.e., shoes, sweaters, etc.).
A method for drying, in conjunction with the drying drawer 30, can shorten the drying cycle to minimize the time required to remove water from an article of clothing, shoes, etc. The method, to be described hereinafter, significantly reduces drying time and energy consumption using only temperature sensors, dampers 70, 72, and the small or low wattage heater 80.
As described above, a method for drying objects can include exhausting air 73 from the drawer through an exhaust duct 40 including dual acting damper 72 having an inlet connected with the drying chamber. Air can be drawn, i.e. ingested, into the drawer through intake duct 44 including dual acting damper 70 having an outlet connected with the chamber. A temperature sensor can be used for measuring the temperature in the drying chamber. Air can be streamed through the drying chamber in the first operational mode when the intake duct damper 70 and the exhaust duct damper 72 are opened (as seen in
The drying chamber can include the multiple baffles 60, 61 disposed on walls inside the chamber for directing air within and around the articles in the chamber. In addition, the drying rack 90 can include a frame 92 that is foldable and/or removable from the chamber. The drying rack can include an accessory shelf 95 and an air diffuser 96. The drying rack 90 can include a pair of foldable shelves 93, 94 that can be used for supporting part of an article, i.e. sleeves S, in an elevated fashion separated from a remaining portion of the article (as seen in
The rack 90 can be configured to enable placement of garments and garment sleeves to enhance drying time. The sleeve rack 90 enhances air flow to all areas of the sleeve and garment torso area. The integral racks 93, 94 on opposing sides of the wire baskets 92 provide for placement of garment sleeves whereby air flows to all surface areas of the garment enabling complete and efficient drying. Each sleeve of a garment can be placed on a sleeve rack such that the torso area of the garment lies separate from the sleeves of the wire basket 92 thereby allowing space and air flow between the sleeves and torso area of the garment.
As described, the dryer drawer system 10 includes a fan 48 for circulating air in the chamber. Air inlet 44 admits air into the multi-sided drying chamber via fan aperture 37. The air exhaust duct 40 guides exhausting air from outlet opening 43 to the exterior of the dryer drawer. In a first operational mode, controller 130 opens dampers 70 and 72 to provide air flow 62 through the chamber. In this mode fan 48 draws exterior air into the drying chamber through inlet 44 and moves it toward the front of the drying chamber where it returns to the exterior through outlet opening 43 and exhaust duct 40. In a second operational mode, controller 130 closes dampers 70 and 72 to provide a recirculating air flow 63 within the chamber. The airflow pattern in this mode is generally from the fan inlet area 46, proximate the rear of the chamber through the area of the chamber above partition 100 to the front wall 34 of the chamber returning to the fan inlet area 46 through the area beneath partition 100 via opening 101 in partition 100 and opening 45 in partition 35. The drying system operates in the first operational mode until the temperature in the chamber rises to a first predetermined temperature, for example _“XX”_degrees F. On reaching this temperature, the controller switches to the second operating mode and operates in this mode until the temperature in the chamber drops to a second predetermined temperature lower than the first predetermined temperature, for example “YY’_degrees F. Upon declining to this temperature, the controller switches back to the first operational mode and repeats the cycle. The system continues to cycle between the first operational mode and the second operational mode as a function of the sensed temperature in the chamber until the desired degree of dryness (i.e. RMC) is detected or a user selected cycle time has expired.
The drying chamber can include airflow 62 through the chamber in the first operational mode when the chamber is at a first temperature. And then the multi-sided drying chamber can include a recirculating airflow 63 within the chamber in the second operational mode when the chamber is at a second temperature. The heater 80 can raise the temperature of the articles within the chamber in order to evaporate moisture from the articles. The heater 80 can alternate between an “on” position for the first operational mode and an “off” position for the second operational mode. Particular arrangements and examples of the aforementioned system are shown in
As shown in
Quantified results have shown that a pair of tennis shoes using the aforementioned drying drawer can reach 6% RMC ten times faster than shoes in a rack dry which are found in current household dryers. This improved shortened drying cycle can also be accomplished using the dryer drawer heater 80 which can be approximately 10%, or less, of the wattage used in today's current household drum dryers.
Phase II is started when Phase I ramps up to a “T1 High” (i.e. 132 degrees F.). Phase II, also called the evaporative phase, works by controlling the temperature modulating dampers 70, 72 while the low wattage heater 80 is on. The dampers 70, 72 are opened when the internal compartment temperature reaches a “T2 High” (i.e. 132 degrees) and then the dampers are closed when the internal temperature reaches a “T2 Low” (i.e. 128 degrees). Fan 48 re-circulates air when dampers 70, 72 are closed, or exchanges outside air when the dampers 70, 72 are open.
Phase III starts when dampers 70, 72 are opened during Phase II and the internal compartment temperature still rises even though the dampers 70, 72 remain open. Phase III, also called the final phase, comprises leaving the dampers 70, 72 open with the fan 48 on. The low wattage heater 80 can be turned off when the internal compartment temperature reaches a “T3 High” (i.e. 136 degrees) and turned back on when the internal compartment temperature falls to a “T3 Low” (i.e. 130 degrees). The cycle control can continue until a predetermined RMC is achieved for the contents inside the drying chamber.
Referring now to
Phase II is started when Phase I ramps up to a “T1 High” (i.e. 136 degrees). Phase II works by controlling the temperature modulating dampers 70, 72 while the low wattage heater 80 remains on. The dampers 70, 72 are opened when the internal compartment temperature reaches a “T2 High” (i.e. 136 degrees) and then the dampers are closed when the internal temperature reaches a “T2 Low” (i.e. 132 degrees).
Phase III starts when dampers 70, 72 are opened during Phase II and the internal compartment temperature still rises (i.e. greater than 136 degrees) even though the dampers 70, 72 remain open. Phase III, also called the final phase, comprises leaving the dampers 70, 72 open with the fan 48 on. The low wattage heater 80 can be turned off when the internal compartment temperature reaches a “T3 High” (i.e. 136.5 degrees) and turned back on when the internal compartment temperature falls to a “T3 Low” (i.e. 132.5 degrees). The cycle control can continue until a predetermined RMC is achieved.
Referring now to
Phase II is started when Phase I ramps up to a “T1 High” (i.e. 136 degrees). Phase II works by controlling the heater and cycling the heater from on to “off” while the dampers remain in the open position. Phase II, for this control cycle, comprises leaving the dampers 70, 72 open and cycling the heater from “off” to “on” as the internal compartment temperature moves from, for example, 136 degrees to 132 degrees, respectively. The cycle control can continue until a predetermined RMC, or predetermined percentage of an RMC, is achieved.
It is to be understood that the present disclosure is not limited to the embodiments and particular temperature thresholds described above, but encompasses any and all embodiments within the scope of the following claims.
