Laundry dryer

Abstract

A laundry dryer is provided. A control device of the laundry dryer is capable of performing a drying operation in which a blowing device is driven to supply the circulating air heated by a heating device into a drying chamber, and a motor is driven to rotate a rotating tub. The drying operation includes a first period in which the control device controls the rotating tub to rotate at a first rotational speed and a second rotational speed, and a second period in which the control device controls the rotating tub to rotate at the first rotational speed and a third rotational speed, the second period being a period after the first period, wherein the first rotational speed is a rotational speed at which laundry in the rotating tub does not lean due to centrifugal force, the second rotational speed is higher than the first rotational speed, and is a rotational speed at which the laundry that has leaned due to the centrifugal force falls in the rotating tub due to gravity, and the third rotational speed is higher than the second rotational speed, and is a rotational speed at which the laundry that has leaned due to the centrifugal force does not fall in the rotating tub due to the gravity.

Description

Technical Field

[0001] This invention relates to a clothes dryer. Background Technology

[0002] As a type of clothes dryer, a washer-dryer is well known to have functions such as washing and drying clothes. In this washer-dryer, a circulating air duct is provided outside the water tank, which serves as the drying chamber. Within this circulating air duct are a heating device, a dehumidifying device, and a blower. During drying operation, the blower circulates the air within the drying chamber through the circulating air duct. At this time, air heated by the heating device is delivered into the drying chamber to heat the clothes inside, and the humid air is repeatedly dehumidified by the dehumidifying device, thereby drying the clothes.

[0003] As is well known, during drying operation, the rotation of the rotating trough within the water tank promotes the exchange of relative positions of the clothes, allowing dry air to contact the entire garment and thus improving drying efficiency. However, with the increasing capacity of clothes dryers and the need to dry large quantities of clothes, the traditional rotation control method cannot adequately promote the exchange of clothes, making it difficult for some parts of the garment to dry completely, which may result in longer drying times.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2017-079927 Summary of the Invention

[0007] A clothes dryer is provided that reduces drying operation time by efficiently bringing dry air into contact with the clothes in the drying chamber.

[0008] The clothes dryer includes: an outer casing; a water tank disposed within the outer casing; a rotating trough disposed within the water tank, forming a drying chamber together with the water tank, which is a bottomed cylindrical shape with an open front and capable of holding clothes; a motor that drives the rotating trough to rotate; a circulating air duct disposed within the outer casing, connected to the drying chamber, and allowing circulating air to pass through it; an air supply device disposed in the circulating air duct, supplying air to the drying chamber; a heating device disposed in the circulating air duct, heating the circulating air; an air inlet disposed at the front or rear of the drying chamber, connecting the circulating air duct to the drying chamber; and a control device that controls the motor, the air supply device, and the heating device. The control device is capable of executing drying operation, in which the air supply device drives the circulating air heated by the heating device to supply the drying chamber, while the motor drives the rotating trough to rotate. The drying operation includes: a first period in which the control device controls the rotation of the rotating trough at a first speed and a second speed, and a second period in which the control device controls the rotation of the rotating trough at the first speed and a third speed, the second period being a period following the first period, wherein the first speed is a speed at which the clothes in the rotating trough will not be biased due to centrifugal force, the second speed is higher than the first speed, and is a speed at which the clothes that have been biased due to centrifugal force fall down in the rotating trough due to gravity, and the third speed is higher than the second speed, and is a speed at which the clothes that have been biased due to centrifugal force will not fall down in the rotating trough due to gravity.

[0009] Based on the above configuration, not only can the dry air come into contact with the clothes at the back of the drying chamber, but it can also efficiently come into contact with the clothes at the front of the drying chamber, thereby reducing the drying operation time. Attached Figure Description

[0010] Figure 1 This is a longitudinal sectional side view showing the schematic configuration of a washer-dryer according to one embodiment.

[0011] Figure 2 This is a longitudinal sectional rear view showing the schematic configuration of a washer-dryer according to one embodiment.

[0012] Figure 3 This is a schematic diagram illustrating the general configuration of the heat pump unit of a washer-dryer according to one embodiment.

[0013] Figure 4 This is a block diagram illustrating the configuration of a control system for a washer-dryer according to one embodiment.

[0014] Figure 5 This is a timing diagram showing the control content of the drying operation performed by the control device of a washer-dryer according to one embodiment.

[0015] Figure 6 It is a graph showing the control of the rotation speed of the rotating tank during the first period of a washer-dryer according to one embodiment.

[0016] Figure 7 This is a conceptual diagram showing the state of the water tank and the interior of the rotating tank when the rotating tank is rotated at a first rotational speed according to one embodiment of a washer-dryer.

[0017] Figure 8 This is a conceptual diagram showing the state of the water tank and the interior of the rotating tank when the rotating tank is rotated at a second rotation speed according to one embodiment of a washer-dryer.

[0018] Figure 9 It is a graph showing the control of the rotation speed of the rotating tank during the second period of a washer-dryer according to one embodiment.

[0019] Figure 10 This is a conceptual diagram showing the state inside the rotating tank of a washer-dryer according to one embodiment, when the rotating tank is rotated at a third rotational speed.

[0020] Figure 11 This is a flowchart illustrating the control contents of a control device during the drying operation of a washer-dryer according to one embodiment.

[0021] Explanation of reference numerals in the attached figures

[0022] 10…Washer and dryer (clothes dryer), 11…Outer casing, 12…Water tank, 13…Rotating trough, 14…Rotating trough motor (motor), 16…Air outlet, 17…Air inlet, 23…Control device, 30…Circulating air path, 36…Exhaust port, 37…Opening and closing device, 39…Air supply device, 40…Heat pump unit (heating device), 51…Gas supply temperature monitoring unit (monitoring unit). Detailed Implementation

[0023] The following description, with reference to the accompanying drawings, describes a washer-dryer according to one embodiment. Figure 1 As shown, the washer-dryer 10, which also functions as a clothes dryer, includes: an outer casing 11, a water tank 12, a rotating trough 13, a rotating trough motor 14, and a door 15. The washer-dryer 10 has a heat pump drying function, for example, a so-called drum washer-dryer in which the rotating shaft of the rotating trough 13 is horizontal or inclined relative to the ground.

[0024] The outer casing 11 is formed into a generally rectangular box shape using steel plates or the like. A water tank 12 is housed inside the outer casing 11. A rotating trough 13 is housed inside the water tank 12. Both the water tank 12 and the rotating trough 13 are formed into a cylindrical shape. The water tank 12 has an opening 121 at one end of its cylindrical shape, and a water tank end plate 122 at the other end. The opening 121 is located above the water tank end plate 122 within the inclined water tank 12.

[0025] Similarly, the rotating trough 13 has an opening 131 at one end of its cylindrical shape, and a rotating trough end plate 132 at the other end. The opening 131 is located above the rotating trough end plate 132 in the inclined rotating trough 13. The opening 131 of the rotating trough 13 is surrounded by the opening 121 of the water tank 12. The water tank 12 and the rotating trough 13 function as a washing chamber and a drying chamber for receiving laundry.

[0026] The water tank 12 has an air outlet 16 and an air inlet 17. The air outlet 16 is, for example, located on the upper front portion of the peripheral wall of the cylindrical portion constituting the water tank 12. The air inlet 17 is located on the end plate 122 of the water tank, slightly above the center of the end plate 122. The air outlet 16 and the air inlet 17 communicate between the interior and exterior of the water tank 12.

[0027] The water tank 12 has a drain section 18 at its rear end, located at the bottom in the direction of gravity. The drain section 18 is located below the air outlet 16 and the air inlet 17. The drain section 18 is configured to have a drain port 123, a drain valve 19, and a drain hose 20. The drain port 123 is located at the bottom of the water tank 12, connecting the interior of the water tank 12 to the outside. The drain valve 19 is configured as, for example, an electromagnetic liquid on / off valve, and is located between the drain port 123 and the drain hose 20. The drain hose 20 connects the drain port 123 to the outside of the machine, serving as a drainage path for draining water from the water tank 12 to the outside. In this case, the drain valve 19 is used to open and close the drainage path between the drain port 123 and the drain hose 20. That is, by opening the drain valve 19, water in the water tank 12 is discharged from the drain port 123 through the drain valve 19 and the drain hose 20 to the outside of the washer-dryer 10.

[0028] The rotating tank 13 has multiple holes 21 and multiple connecting openings 22. The holes 21 and connecting openings 22 connect the interior of the rotating tank 13 to the exterior. Holes 21 are formed throughout the entire area of ​​the peripheral wall of the cylindrical portion constituting the rotating tank 13. Connecting openings 22 are formed throughout the entire area of ​​the end plate 132 of the rotating tank. During washing operations, including washing, draining, rinsing, and dehydrating cycles, the holes 21 and connecting openings 22 primarily function as water inlets and outlets, while during drying operations, they primarily function as ventilation holes for air inlets and outlets. Additionally, Figure 1 For simplicity, only a portion of the multiple holes 21 and the connecting openings 22 are shown. Additionally, although not shown in detail, multiple baffles are provided inside the cylindrical portion of the rotating tank 13. These baffles agitate the laundry items, such as clothes, contained within the rotating tank 13.

[0029] A rotary tank motor 14 is mounted on the outer side of the tank end plate 122 of the tank 12. The rotary tank motor 14 is, for example, an external rotor type DC brushless motor. The shaft 141 of the rotary tank motor 14 passes through the tank end plate 122 and protrudes into the inner side of the tank 12, and is fixed to the center of the rotary tank end plate 132. Accordingly, the rotary tank motor 14 causes the rotary tank 13 to rotate relative to the tank 12. In this case, the shaft 141, the rotation axis of the rotary tank 13, and the central axis of the tank 12 are all aligned.

[0030] Door 15 is mounted on the outer surface of outer casing 11 via a hinge (not shown). Door 15 rotates around the hinge to open and close an opening (not shown) formed on the front surface of outer casing 11. The opening in outer casing 11 is connected to opening 121 of sink 12 via bellows 111. Laundry items such as clothes can be loaded and unloaded relative to the rotating groove 13 through openings 121 and 131 while door 15 is open.

[0031] The washer and dryer has the following features: Figure 4 The control device 23 or operation panel 24 shown, and Figure 2 The water supply device 25 is shown. The control device 23 is configured with a microcomputer as the main body to control all the operations of the washer-dryer 10. The microcomputer has, for example, a CPU 231 or a storage area 232 such as ROM, RAM and rewritable flash memory.

[0032] like Figure 1 As shown, the operation panel 24 is located on, for example, the front surface of the outer casing 11 and above the door 15. Figure 4 As shown, the operation panel 24 is connected to the control device 23. Users can select various settings such as washing operation and drying operation by operating the operation panel 24.

[0033] like Figure 2 As shown, the water supply device 25 includes a water supply box 26, a water supply valve 27, and a water supply hose 28. The water supply valve 27 is connected to a control device 23 and is opened and closed under the control of the control device 23. One end of the water supply hose 28 is connected to the water supply valve 27, and the other end is connected to an external water source such as a water pipe. The control device 23 supplies water from the water source to the water tank 12 through the water supply hose 28, the water supply valve 27, and the water supply box 26 by opening and closing the water supply valve 27.

[0034] For example Figure 3 As shown, the washer-dryer 10 includes a circulating air duct 30 and a heat pump unit 40. The circulating air duct 30 is located outside the water tank 12 and connects the air outlet 16 to the air inlet 17. Specifically, the circulating air duct 30 is configured to include an exhaust pipe 31, a filter device 32, a connecting pipe 33, a heat exchange unit 34, and an air supply pipe 35. Details will be described later. Air flows along the air duct 30... Figures 1-3 The loop continues in the direction of the middle arrow A.

[0035] For example Figure 1 As shown, the exhaust pipe 31 connects the air outlet 16 of the water tank 12 to the filter device 32. The exhaust pipe 31 is, for example, made of a corrugated flexible hose. The filter device 32 is located on the upper inner side of the outer casing 11 and is positioned above the water tank 12 and the rotating tank 13. A filter 321 is provided inside the filter device 32. The filter device 32 removes foreign matter such as lint from the air outlet 16 by passing the air discharged from the air outlet 16 through the filter 321. The filter device 32 is connected to the upstream side of the heat exchange section 34 via a connecting pipe 33. The connecting pipe 33 has a first portion 331 extending generally horizontally behind the filter device 32, and a second portion 332 extending downward and connected to the heat exchange section 34. The heat exchange section 34 is located on the lower inner side of the outer casing 11 and is positioned below the water tank 12 and the rotating tank 13.

[0036] like Figure 1 As shown, the circulating air passage 30 includes an exhaust port 36, an opening / closing device 37, and an intake port 38. The exhaust port 36 is located at the first portion 331 of the connecting pipe 33. The exhaust port 36 is configured such that the upper opening of the connecting pipe 33 is formed into, for example, multiple narrow slits, connecting the interior and exterior of the circulating air passage 30. The opening / closing device 37 is located on the exterior side of the exhaust port 36. The opening / closing device 37 can be rotated using a motor (not shown) with one end as a fulcrum to open and close the exhaust port 36. The opening / closing device 37 is connected to a control device 23 and is driven to open and close under the control of the control device 23.

[0037] An air intake 38 is located at the upper part of the heat exchange section 34. The air intake 38 is formed by opening a portion of the heat exchange section 34, thereby connecting the interior of the heat exchange section 34 and, consequently, the interior of the circulating air path 30, to the outside. When the opening / closing device 37 is opened and placed in the open state, as... Figure 1 As indicated by the middle arrow A1, a portion of the air within the circulating air passage 30 is discharged outside the circulating air passage 30 through the exhaust port 36. Therefore, since the circulating air passage 30 is under reduced pressure, air from outside the circulating air passage 30 is drawn into the circulating air passage 30 through the intake port 38. In this situation, due to the negative pressure generated within the circulating air passage 30, the airflow within the circulating air passage 30 increases due to Bernoulli's principle. That is, the airflow of dry air supplied to the water tank 12 and the rotating tank 13 increases. On the other hand, the discharge of a portion of warm air from the exhaust port 36 and the intake of air from outside the circulating air passage 30 through the intake port 38 are the main reasons for lowering the temperature of the air within the circulating air passage 30.

[0038] The heat pump unit 40 has the function of generating dry warm air by dehumidifying and heating the air passing through the heat exchange section 34 in the circulating air path 30. That is, the heat pump unit 40 functions as a heating device that dehumidifies and heats the air flowing into the circulating air path 30 from the water tank 12, turning it into warm air, and then supplies it back into the water tank 12 and the rotating tank 13. The heat exchange section 34 is equipped with an evaporator 41 and a condenser 42, which form part of the heat pump unit 40. The evaporator 41 is positioned upstream of the condenser 42 relative to the air flow within the heat exchange section 34 during drying operation. The air passing through the heat exchange section 34 is cooled by the evaporator 41, thereby dehumidifying it. The air dehumidified by the evaporator 41 is then heated by the condenser 42 to become warm air.

[0039] like Figure 3 As shown, the heat pump unit 40 includes a compressor 43 and a pressure reducing device 44 in addition to the evaporator 41 and condenser 42. The compressor 43 and pressure reducing device 44 are located outside the heat exchange section 34. The heat pump unit 40 is configured such that the condenser 42, pressure reducing device 44, and evaporator 41 are sequentially connected in a ring shape relative to the direction of refrigerant flow based on the compressor 43. That is, the refrigerant flows along... Figure 3 The refrigerant flows in the direction of arrow B. The evaporator 41 and condenser 42 are constructed, for example, by means of a tube having multiple fins arranged at minute intervals, through which refrigerant passes, thereby facilitating heat exchange between the air passing between the fins and the refrigerant. The evaporator 41 and condenser 42 function as heat exchangers.

[0040] The compressor 43 supplies refrigerant to the condenser 42 via compression. The compressor 43 is connected to the control device 23 and is driven and stopped under the control of the control device 23. Furthermore, a receiver 45 is provided on the suction side 431 of the compressor 43. The receiver 45 suppresses pressure fluctuations in the refrigerant flowing into the compressor 43. A pressure reducing device 44 reduces the pressure of the refrigerant discharged from the condenser 42, which has been pressurized into a liquid state, making it a low-pressure gas-liquid mixture. In this case, the pressure reducing device 44 may be constructed of, for example, a capillary tube, but it could also be an electromagnetically operated expansion valve that can be opened and closed under the control of the control device 23.

[0041] The downstream side of the heat exchange section 34 is connected to the air inlet 17 of the water tank 12 via an air supply pipe 35. An air supply device 39 is provided at the connection between the heat exchange section 34 and the air supply pipe 35. Figure 2 As shown, the air supply device 39 is configured to include a fan motor 391 and a fan 392. The air supply device 39 is configured such that the rotational speed of the fan motor 391, i.e., the rotational speed of the fan 392, can be changed by the control device 23. Furthermore, in the following description, the rotational speeds of the fan motor 391 and the fan 392 will be referred to as the rotational speed of the air supply device 39.

[0042] The air supply device 39 draws in air from the heat exchange section 34 and discharges it towards the air supply duct 35. Accordingly, as Figure 1 , Figure 2 ,as well as Figure 3 As indicated by the middle arrow A, this results in the flow of air circulating in the water tank 12 and the circulating air passage 30. In this case, from the perspective of the air flow within the circulating air passage 30, the air outlet 16 is the upstream side and the air inlet 17 is the downstream side.

[0043] In this configuration, when the compressor 43 and the air supply device 39 are driven, warm air, dehumidified and heated in the heat exchange section 34, is supplied to the water tank 12 from the air inlet 17 via the air supply pipe 35 through the air supply device 39. Thereafter, the warm air mainly enters the rotating tank 13 through the connecting port 22, raising the temperature of the laundry in the rotating tank 13 and removing moisture from the laundry before mainly flowing out of the hole 21 to the outside of the rotating tank 13. Furthermore, air containing moisture is drawn into the circulating air path 30 from the air outlet 16. The air drawn into the circulating air path 30 first passes through the exhaust pipe 31 and the filter device 32. Then, it flows to the heat exchange section 34 via the connecting pipe 33. Thus, the air entering the circulating air path 30 from the water tank 12 is dehumidified and heated within the circulating air path 30 before being supplied back to the water tank 12.

[0044] like Figures 1 to 4As shown, the washer-dryer 10 includes a gas supply temperature monitoring unit 51, which serves as a monitoring unit. The gas supply temperature monitoring unit 51 is connected to the control device 23. Figure 3 As shown, the air supply temperature monitoring unit 51 is installed within the circulating air path 30 to detect the temperature of the air within the circulating air path 30. Specifically, the air supply temperature monitoring unit 51 is located between the condenser 42 and the air inlet 17, and is positioned near the air inlet 17. The air supply temperature monitoring unit 51 detects the temperature of the air supplied to the water tank 12 and the rotating tank 13, which serve as the drying chamber, after passing through the air supply pipe 35, i.e., the air supplied to the drying chamber after being heated by the heat exchange unit 34, i.e., the air supply temperature x.

[0045] like Figure 4 As shown, the washer-dryer 10 includes a motor speed monitoring unit 52 and a fan speed monitoring unit 53. The motor speed monitoring unit 52 monitors the rotational speed of the rotary drum motor 14. The motor speed monitoring unit 52 can monitor the rotational speed of the rotary drum motor 14 by measuring the q-axis current in the vector control of the rotary drum motor 14, or it can install a rotation sensor on the rotary drum motor 14 and use the rotation sensor to monitor the rotational speed of the rotary drum motor 14.

[0046] The fan speed monitoring unit 53 monitors the rotational state of the air supply device 39. For example, the fan speed monitoring unit 53 detects the induced voltage of the fan motor 391 of the air supply device 39, thereby enabling the monitoring of the rotational speed nx of the air supply device 39. Alternatively, an encoder or other rotation detector can be installed on the fan motor 391 of the air supply device 39, allowing hardware-based detection of the rotational state of the air supply device 39.

[0047] The control device 23 can selectively perform washing operation, drying operation, and washing-drying operation. Washing-drying operation is a mode of drying operation that follows washing operation.

[0048] In the above configuration, when the clothes are contained in the rotating trough 13, and the user sets a drying operation including washing and drying operations on the control panel 24, the control device 23 executes the drying operation alone, or executes the drying operation after the washing operation. During the drying operation, the rotating trough 13 is rotated appropriately by the rotating trough motor 14, and the compressor 43 of the heat pump unit 40 is driven, as well as the air supply device 39.

[0049] During the drying operation, the control device 23 controls the rotary drum 13 to periodically rotate clockwise and counterclockwise by driving the rotary drum motor 14. This improves the drying efficiency by promoting agitation of the clothes compared to, for example, only clockwise rotation. In this embodiment, the length of one cycle during clockwise rotation is set to be the same as the length of one cycle during counterclockwise rotation. That is, when the length of one cycle including either clockwise or counterclockwise rotation is set to u0, the length of the period for one cycle of clockwise rotation and one cycle of counterclockwise rotation is u0 × 2. Furthermore, in this case, the length u0 of one cycle including either clockwise or counterclockwise rotation can be set to, for example, 60 seconds to 120 seconds. In this embodiment, the length u0 of one cycle is set to 90 seconds.

[0050] like Figure 5 As shown, the drying operation is configured to include a first period T1 and a second period T2. The first period T1 corresponds to the first half of the entire drying operation. The second period T2 is the period that follows the first period T1 and corresponds to the second half of the entire drying operation period T. In this case, the control device 23 sets the entire drying operation period T based on, for example, the operating mode set by the user, the weight of the clothes, the outside temperature, etc., according to a predetermined drying operation time data table. In this case, the control device 23 stores the drying operation time data table in the storage area 232.

[0051] During the first period T1, the washer-dryer 10 primarily dries clothes located near the air inlet 17, that is, clothes located on the side of the rotating trough end plate 132 of the rotating trough 13. During the second period T2, the washer-dryer 10 primarily dries clothes located away from the air inlet 17, that is, clothes located on the side of the opening 131 of the rotating trough 13.

[0052] First, during the first period T1, the control device 23 controls the rotation of the rotating groove 13 at at least two rotational speeds n. The first period T1 is the period during which the control device 23 controls the rotating groove 13 to rotate periodically at a first rotational speed n1 and a second rotational speed n2. In this case, the rotational speed n includes both forward and reverse rotational speeds. That is, unless otherwise specified, the rotational speed n represents the absolute value of the rotational speed of the rotating groove 13. In this embodiment, as... Figure 6 As shown, the control device 23 controls the rotation of the rotating groove 13 at a first rotational speed n1 and a second rotational speed n2. The second rotational speed n2 is set to be greater than the first rotational speed n1.

[0053] Specifically, the first rotational speed n1 is a speed such that the garments contained in the rotating tank 13 do not lean too far against the wall of the rotating tank 13 due to centrifugal force. The first rotational speed n1 can be set, for example, in the range of 40 rpm to 60 rpm. In this embodiment, the first rotational speed n1 is set to 50 rpm, for example.

[0054] The second rotational speed n2 is the rotational speed at which the clothes contained in the rotating tank 13 are biased against the wall of the rotating tank 13 due to centrifugal force, but fall down due to gravity. The second rotational speed n2 can be set, for example, in the range of 65 rpm to 85 rpm. In this embodiment, the second rotational speed n2 is set to 75 rpm for example.

[0055] During the period when the rotating groove 13 rotates at the first rotational speed n1, such as Figure 7 As shown, the rotating groove 13 is filled with clothing, making relative movement between the clothing contained within it difficult. Therefore, as... Figure 7 Dry air supplied from air inlet 17, as indicated by the middle arrow A2, is continuously blown onto the similar clothing. During the rotation of the rotating tank 13 at a second rotational speed n2, a portion of the clothing, such as... Figure 8 As indicated by the middle arrow C1, the clothes fall due to gravity. This facilitates the replacement of clothes, allowing dry air to reach the new clothes. By periodically repeating the rotation at the first speed n1 and the second speed n2, clothes, especially those near the air inlet 17, are generally able to be dried.

[0056] During the first period T1, the period u1 during which the control device 23 rotates the rotating trough 13 at the second rotational speed n2 is set to be at least 1 / 5 of the length u0 of the first period. In other words, during the entire first period T1, the period during which the rotational speed n of the rotating trough 13 is at the second rotational speed n2 is set to be at least 1 / 5 of the length of T1. Accordingly, the period during which a portion of the clothing pushed against the wall of the rotating trough 13 falls down due to gravity, i.e., the period during which clothing replacement is facilitated, is sufficiently ensured.

[0057] Furthermore, the control device 23 controls the opening and closing of the opening and closing device 37 during the drying operation. Specifically, during the first period T1, the control device 23 controls the opening and closing of the opening and closing device 37 based on the supply air temperature x. At the start of the drying operation, the control device 23 performs a process that puts the opening and closing device 37 in the open state. Accordingly, the air volume in the circulating air path 30 increases, and the air volume of dry air supplied to the drying chamber increases. Therefore, the control device 23 can promote the drying of clothes by increasing the air volume. When circulating air is discharged from the exhaust port 36 and air is drawn in from the intake port 38, since part of the air heated by the heat pump unit 40 is discharged and unheated external air is drawn in, the temperature of the circulating air in the circulating air path 30 tends to decrease. However, in the initial stage of the drying operation, since the clothes contain a lot of moisture, the drying of the clothes can be promoted even if the dry air is relatively low due to the function of the heat pump. In addition, in this case, putting the opening / closing device 37 into the open state includes: opening the opening / closing device 37 which was originally in the closed state, and maintaining the opening / closing device 37 which was originally in the open state in the open state.

[0058] As the drying process progresses, such as Figure 5 As shown, the gas supply temperature x monitored by the gas supply temperature monitoring unit 51 shows an increase. When the gas supply temperature x monitored by the gas supply temperature monitoring unit 51 is above a predetermined temperature x0, the control device 23 performs the process of shutting down the on / off device 37. In this case, the predetermined temperature x0 can be set, for example, to 55°C to 70°C. In this embodiment, the predetermined temperature x0 is set to 60°C. Accordingly, although the air volume in the circulating air path 30 decreases, since no heat is lost due to exhaust, the temperature of the circulating air is easily maintained at a high temperature.

[0059] Next, during the second period T2, the control device 23 controls the rotation of the rotating groove 13 at at least two rotational speeds. The second period T2 follows the first period T1 and is the period during which the control device 23 controls the rotation of the rotating groove 13 to rotate periodically at a first rotational speed n1 and a third rotational speed n3. In this case, as... Figure 9 As shown, the control device 23 controls the rotation of the rotating groove 13 to a first rotational speed n1 and a third rotational speed n3. The third rotational speed n3 is set to be greater than both the first rotational speed n1 and the second rotational speed n2.

[0060] The third rotational speed n3 is the rotational speed at which the clothes contained in the rotating tank 13 are biased against the wall of the rotating tank 13 due to centrifugal force and will not fall due to gravity. The third rotational speed n3 can be set to, for example, 90 rpm to 110 rpm. The third rotational speed n3 can be set to, for example, 100 rpm.

[0061] During the period when the rotating groove 13 rotates at the third rotational speed n3, such as Figure 10 As indicated by arrow C2, the clothing is thrown against the wall of the rotating tank 13 due to centrifugal force. In this case, since the clothing does not fall due to gravity, a space without clothing appears in the center of the rotating tank 13, i.e., the axis of rotation and its surroundings. That is, a space is created where dry air can enter the tunnel between the clothing. Therefore, a portion of the dry air supplied from the air inlet 17... Figure 10 As indicated by arrow A3, the air can enter towards the opposite side of the air inlet 17, i.e., the opening 131, without being obstructed by clothing near the air inlet 17. Therefore, drying air can be blown onto the clothing located on the side of the opening 131. By periodically repeating rotation at the first speed n1 and the third speed n3, clothing located on the side of the opening 131 can be dried, especially.

[0062] During the second period T2, the period u2 during which the control device 23 rotates the rotating groove 13 at a third rotational speed n3 within one cycle is set within the range of 1 / 3 to 1 / 2 of the length u0 of one cycle. In other words, the period during which the rotational speed n of the rotating groove 13 is the third rotational speed n3 within the entire second period T2 is set within the range of 1 / 3 to 1 / 2 of the length of T1. Accordingly, it can be sufficiently ensured that during the period when there are gaps between the garments through which dry air can pass, that is, during the period when dry air can be blown onto the garments located away from the air inlet 17.

[0063] like Figure 5 As shown, during the second period T2, the control device 23 keeps the opening / closing device 37 in the closed state. Therefore, during the latter half of the drying process, when the moisture content of the clothes decreases and the heat pump's function becomes less effective, the temperature of the drying air can be maintained at a high temperature, which facilitates drying. Alternatively, in other embodiments, the opening / closing device 37 can be opened during the second period T2 if the supply air temperature x monitored by the supply air temperature monitoring unit 51 is above a predetermined temperature x1. In this case, the predetermined temperature x1 can be set, for example, to 70°C to 80°C. This prevents the circulating air temperature in the circulating air path 30 from becoming too high, which could lead to excessive load on the compressor 43.

[0064] The following also refers to Figure 11 This indicates that the drying process is in operation. Control device 23 activates at the start of the drying process ( Figure 11In step S11, based on the data table stored in storage area 232, the duration T of the entire drying operation is set. Accordingly, a first duration T1 and a second duration T2 are set respectively. In addition, in step S12, control device 23 drives air supply device 39 and compressor 43. In this case, driving air supply device 39 or compressor 43 includes: starting to drive the undriven air supply device 39 or compressor 43, and maintaining the drive of the driven air supply device 39 or compressor 43. For example, if a preheating and dehydration operation is performed before the drying operation, where warm air is supplied to the rotary trough 13 while dehydration is carried out, at least one of the air supply device 39 and compressor 43 may be driven at the start of the drying operation.

[0065] Next, in step S13, the control device 23 performs an opening process to put the opening and closing device 37 in the open state. Accordingly, a portion of the air in the circulating air passage 30 is discharged from the exhaust port 36, and air from outside the circulating air passage 30 is supplied from the intake port 38, thereby increasing the air volume in the circulating air passage 30.

[0066] Next, in step S14, the control device 23 begins the first stroke. The first stroke is a process in which the control device 23 periodically reverses the rotational speed n of the rotating groove 13 at a first rotational speed n1 and a second rotational speed n2. During the first stroke, drying of clothes located near the air inlet 17 is promoted mainly in the drying chamber.

[0067] Furthermore, in step S15, the control device 23 determines whether the supply temperature x monitored by the supply temperature monitoring unit 51 is above the specified temperature x0. If the supply temperature x monitored by the supply temperature monitoring unit 51 is below the specified temperature x0, the control device 23 repeats step S15. If the supply temperature x monitored by the supply temperature monitoring unit 51 is above the specified temperature x0, the control device 23 proceeds to step S16. In step S16, the control device 23 performs a shut-off process that closes the opening and closing device 37. Accordingly, the air in the circulating air path 30 is not discharged to the outside from the exhaust port 36, thereby easily maintaining the temperature of the air in the circulating air path 30 at a high temperature.

[0068] Next, in step S17, the control device 23 determines whether the first period T1 has elapsed since the start of the first stroke. If the first period T1 has not elapsed since the start of the first stroke, the control device 23 repeats step S17. If the first period T1 has elapsed since the start of the first stroke, the control device 23 proceeds to step S18.

[0069] In step S18, control device 23 begins the second stroke. The second stroke is a process in which control device 23 periodically reverses the rotational speed n of the rotating groove 13 at a first rotational speed n1 and a third rotational speed n3. During the second stroke, drying of clothing located away from the air inlet 17 is promoted, primarily within the drying chamber.

[0070] Next, in step S19, the control device 23 determines whether the second period T2 has elapsed since the start of the second stroke. If the second period T2 has not elapsed, the control device 23 repeats step S19. If the second period T2 has elapsed, the control device 23 causes the process to proceed to step S20.

[0071] In step S20, control device 23 stops the drive of air supply device 39 and compressor 43. Next, in step S21, control device 23 stops the drive of rotary drum motor 14, thereby stopping the rotation of rotary drum 13. Then, the drying operation ends (end).

[0072] Furthermore, following the drying operation, the control device 23 may also perform, for example, operations to prevent clothes from tangling or operations to cool the drying chamber. When performing the operation to prevent clothes from tangling, the control device 23 may, in step S21, continue to rotate the rotating trough 13 by, for example, reducing its speed, without stopping the drive of the rotating trough motor 14; or in step S21, continue to deliver air to the drying chamber without stopping the drive of the air supply device 39. Similarly, when performing the operation to cool the drying chamber, the control device 23 may, in step S21, continue to deliver air to the drying chamber without stopping the drive of the air supply device 39.

[0073] Here, especially when the rated capacity of clothes is fully loaded, the volume increases during drying operation, particularly in the latter half of the drying process, and the rotating trough 13 becomes filled with clothes, making it easy to clog the air passages. Furthermore, since there is limited space for the clothes to rotate freely within the rotating trough 13, relative movement between clothes is difficult. Consequently, in conventional clothes dryers, only clothes near the air inlet 17 are dried first, while clothes further away from the air inlet 17 are not dried easily. This results in the following problems: the time required to dry all clothes tends to increase, and it becomes a major cause of uneven drying.

[0074] According to the embodiments described above, the washer-dryer 10, as a clothes dryer, includes: an outer casing 11, a water tank 12, a rotating trough 13, a rotating trough motor 14, a circulating air duct 30, an air supply device 39, a heat pump unit 40 as a heating device, an air inlet 17, and a control device 23. The water tank 12 is disposed inside the outer casing 11. The rotating trough 13 is disposed inside the water tank 12 and together with the water tank 12 forms a drying chamber, and is a bottomed cylindrical shape with an open front, capable of holding clothes inside. The rotating trough motor 14 drives the rotating trough 13 to rotate. The circulating air duct 30 is connected to the drying chamber, allowing circulating air to pass through it. The air supply device 39 is disposed in the circulating air duct 30 and delivers air to the drying chamber. The heat pump unit 40 is disposed in the circulating air duct 30 and heats the circulating air. The air inlet 17 is disposed at the front or rear of the drying chamber, connecting the circulating air duct 30 to the drying chamber. The control device 23 controls the rotary slot motor 14, the air supply device 39, and the heat pump unit 40.

[0075] The control device 23 is capable of performing a drying operation in which the rotating drum 13 is rotated by driving the rotating drum motor 14 while simultaneously supplying circulating air heated by the heat pump unit 40 to the drying chamber via the air supply device 39. The drying operation is configured to include a first period T1 and a second period T2. The first period T1 is the period during which the control device 23 controls the rotation of the rotating drum 13 at a first speed n1 and a second speed n2, where the first speed n1 is a speed at which the clothes will not shift due to centrifugal force within the rotating drum 13, and the second speed n2 is higher than the first speed n1 and is a speed at which the clothes that shift due to centrifugal force will fall due to gravity within the rotating drum 13. The second period T2 is the period following the first period T1, and is the period during which the control device 23 controls the rotation of the rotating tank 13 at a first speed n1 and a third speed n3, wherein the third speed n3 is higher than the second speed n2, and is the speed at which the clothes that are biased by centrifugal force will not fall down in the rotating tank 13 due to gravity.

[0076] Accordingly, in this embodiment, during the first period T1, clothes that are easily blown by the air from the air supply device 39, i.e., near the air inlet 17, are primarily dried. Furthermore, during the second period T2, when rotating at a third rotation speed n3, the clothes are pushed against the rotating trough 13 due to centrifugal force, thus creating channels for dry air between the clothes. Therefore, dry air can also easily reach the clothes that are away from the air inlet 17, i.e., those located on the side of the opening 131. Therefore, the overall drying efficiency of the clothes is improved, drying time is shortened, and uneven drying is suppressed. This effect is particularly significant when there is a large amount of clothing contained in the rotating trough 13, i.e., clothing contained in the drying chamber, such as 80% or more of the rated capacity of the washer-dryer 10.

[0077] Here, during the second period T2, if the period u2 during which the rotational speed n of the rotating groove 13 is maintained at the third rotational speed n3 is too short, the time that the clothes are pushed against the wall of the rotating groove 13 will be shorter, and correspondingly, no hole will be formed for dry air to pass through, or even if it is formed, it will disappear immediately. In this case, it is difficult for dry air to be blown to a position away from the air inlet 17.

[0078] In this embodiment, during the second period T2, the rotational speed n of the rotating groove 13 is maintained at the third rotational speed n3 for a period u2 of 1 cycle u0, which is set to 1 / 3 to 1 / 2 of the second cycle u0.

[0079] Therefore, by ensuring the period during which the cavity through which dry air passes, it is possible to ensure that the dry air reaches the clothes located away from the air inlet 17. As a result, clothes located away from the air inlet 17 are also easier to dry, the overall drying efficiency of the clothes is improved, and the drying time can be shortened.

[0080] Here, during the first period T1, if the period u1 during which the second rotational speed n2 is maintained is too short, the time that the clothes are pushed against the wall of the rotating groove 13 will be shorter, and correspondingly, it will be difficult for the relative movement of the clothes, i.e., the replacement of the clothes, to occur. In this case, since the dry air is likely to blow only onto the same clothes, it is possible that some clothes will be over-dried and some clothes will not be dried.

[0081] In this embodiment, during the first period T1, the rotational speed n of the rotating groove 13 is maintained at a period u2 of the second rotational speed n2 for a period of 1 / 5 or more of one cycle u0.

[0082] Therefore, during a certain period, because the clothes are repeatedly pushed against the wall of the rotating trough 13 and then fall due to gravity, relative movement, or replacement, of the clothes easily occurs. Thus, during the first period T1, the amount of clothes that come into contact with dry air and are dried can be increased. Therefore, the overall drying efficiency of the clothes is improved, thereby shortening the drying time.

[0083] Furthermore, according to this embodiment, the washer-dryer 10, which is a clothes dryer, includes: an exhaust port 36, an opening and closing device 37, and an air supply temperature monitoring unit 51 as a monitoring unit. The exhaust port 36 is provided in the circulating air passage 30 and has the function of discharging circulating air to the outside of the circulating air passage 30. The opening and closing device 37 opens and closes the exhaust port 36. The air supply temperature monitoring unit 51 has the function of monitoring the temperature of the circulating air supplied from the air inlet 17 to the rotating tank 13. During the first period T1, the control device 23 performs an opening process to open the opening and closing device 37 when the air supply temperature x of the circulating air monitored by the air supply temperature monitoring unit 51 reaches or exceeds a predetermined temperature x0.

[0084] Accordingly, when the opening / closing device 37 is opened, a portion of the air in the circulating air path 30 is discharged, thereby reducing the pressure inside the circulating air path 30 and making it easier to draw air from outside the circulating air path 30. As a result, the air volume in the circulating air path 30 increases. In the first half of the drying operation, that is, the initial stage of the first period T1, the clothes contain more moisture. Therefore, even if the temperature of the circulating air is low, the drying of the clothes can be promoted by the function of the heat pump. That is, in the initial stage of the first period T1, the control device 23 focuses more on increasing the air volume than on raising the temperature of the circulating air, thereby promoting the drying of the clothes.

[0085] Here, when the opening / closing device 37 is in the open state to discharge warm circulating air to the outside, the internal heat within the circulating air passage 30 is correspondingly released. After the drying operation has progressed to a certain extent, since the moisture content of the clothes is less than at the initial stage of the first period T1, the temperature of the circulating air becomes low, making it difficult to dry the clothes using the heat pump function. Therefore, if the supply air temperature x monitored by the supply air temperature monitoring unit 51 reaches x0 or higher, the control device 23 will close the opening / closing device 37 to suppress the exhaust volume, thereby easily increasing the temperature of the circulating air. Although the airflow of the circulating air decreases, in the second period T2, the rotational speed n of the rotating groove 13 is increased to form an air passage, thus improving the drying efficiency in the latter half of the drying cycle. Therefore, throughout the entire drying operation, the overall drying efficiency of the clothes is improved, thereby shortening the drying time.

[0086] While one embodiment of the present invention has been described above, this embodiment is merely an example and is not intended to limit the scope of the invention. This new embodiment can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are all included within the scope and spirit of the invention, and are included within the scope of the invention as described in the claims and its equivalents.

Claims

1. A clothes dryer comprising: an outer casing; a water tank disposed inside the outer casing; and a rotating trough disposed inside the water tank, forming a drying chamber together with the water tank, which is a bottomed cylindrical shape with an open front and capable of holding clothes inside. A motor drives the rotating trough to rotate; a circulating air duct is located inside the outer casing, connected to the drying chamber, and allows circulating air to pass through it; an air supply device is located in the circulating air duct and delivers air to the drying chamber. A heating device, disposed in the circulating air duct, heats the circulating air; an air inlet, disposed at the front or rear of the drying chamber, connects the circulating air duct to the drying chamber; and a control device, which controls the motor, the air supply device, and the heating device, characterized in that… The control device is capable of performing drying operations, during which the air supply device is driven to supply the circulating air heated by the heating device into the drying chamber, and the motor is driven to rotate the rotating trough. The drying operation includes: a first period in which the control device controls the rotation of the rotating trough at a first speed and a second speed, and a second period in which the control device controls the rotation of the rotating trough at the first speed and a third speed, the second period being a period following the first period, wherein the first speed is a speed at which the clothes in the rotating trough will not be biased due to centrifugal force, the second speed is higher than the first speed, and is a speed at which the clothes that have been biased due to centrifugal force fall down in the rotating trough due to gravity, and the third speed is higher than the second speed, and is a speed at which the clothes that have been biased due to centrifugal force will not fall down in the rotating trough due to gravity.

2. The clothes dryer according to claim 1, characterized in that, During the second period, the rotational speed of the rotating groove is maintained for 1 / 3 to 1 / 2 of a cycle during the third rotational speed period.

3. The clothes dryer according to claim 1 or 2, characterized in that, During the first period, the rotational speed of the rotating groove is maintained at more than 1 / 5 of a cycle during the second rotational speed period.

4. The clothes dryer according to claim 1 or 2, characterized in that, It comprises: an exhaust port disposed in the circulating air path to discharge the circulating air to the outside of the circulating air path; an opening and closing device for opening and closing the exhaust port; and a monitoring unit for monitoring the temperature of the circulating air supplied from the air inlet to the rotating tank. The control device performs the following during the first period: when the temperature of the circulating air monitored by the monitoring unit reaches or exceeds a predetermined temperature, the opening process of the opening and closing device is initiated.

5. The clothes dryer according to claim 3, characterized in that, It comprises: an exhaust port disposed in the circulating air path to discharge the circulating air to the outside of the circulating air path; an opening and closing device for opening and closing the exhaust port; and a monitoring unit for monitoring the temperature of the circulating air supplied from the air inlet to the rotating tank. The control device performs the following during the first period: when the temperature of the circulating air monitored by the monitoring unit reaches or exceeds a predetermined temperature, the opening process of the opening and closing device is initiated.

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