Washing and drying machine

Abstract

To provide a washing and drying machine capable of detecting and notifying to a user that a dry filter is left unmounted on a circulation passage, while suppressing increase in cost.SOLUTION: A washing and drying machine 1 includes: a second dry filter 170 arranged in a circulation passage 110 connected to an outer tub 20, and attachable / detachable with respect to the circulation passage 110; an air trap connected to a bottom part of the outer tub 20; a water level sensor for detecting an air pressure in the air trap which changes according to the water level in the outer tub 20, and for outputting a detection signal of the value according to the air pressure; a control part; and a display part. The control part determines whether or not the second dry filter 170 is mounted on the circulation passage 110 based on a detection signal outputted from the water level sensor in a state where the air is circulating between the outer tub 20 and the circulation passage 110 by the operation of a blower fan 120, and in the case where it is determined that the second dry filter 170 is not mounted on the circulation passage 110, it allows the display part to perform notification showing that the second dry filter 170 is unmounted.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a washing and drying machine. [Background technology]

[0002] Patent document 1 describes a drum-type washer-dryer having an air blowing means, a dehumidifying means, and a heating means, and a circulating air passage (circulation path) through which hot air circulates between the water tub (outer tub), and a filter device consisting of a detachable main filter and a backup filter arranged in a filter chamber that forms part of the circulating air passage, and which is equipped with a filter detection device that detects the attachment and detachment of the main filter and the backup filter to the filter chamber.

[0003] In the washer-dryer of Patent Document 1, the filter detection device has a pair of built-in magnetic response switches, and the main filter and backup filter have built-in magnets. When the main filter and backup filter are installed in the correct position, the magnets of each filter face the pair of magnetic response switches, causing the filter detection device to respond and output an electrical signal to the outside. If the two filters are not installed in the correct position, the filter detection device does not respond and does not output an electrical signal.

[0004] Therefore, in this washer-dryer, if the filter detection device detects that the filter device is not properly installed, the filter detection device can notify the user of the abnormality and encourage the user to install the filter in the correct position. Also, in this washer-dryer, if the user forgets to install the filter device in the filter chamber, i.e., in the circulation air path, the filter detection device can detect this. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-99980 Summary of the Invention [Problem to be solved by the invention]

[0006] However, since the above-described washing / drying machine is configured to include a filter detection device for detecting whether the filter device is attached to or detached from the circulation air passage, an increase in product cost due to the filter detection device is unavoidable.

[0007] The present invention has been made in consideration of such problems, and aims to provide a washer-dryer that can detect when a drying filter has been left attached to the circulation path and notify the user, while suppressing increases in costs. [Means for solving the problem]

[0008] A washer-dryer according to a main aspect of the present invention includes an outer tub disposed within a housing, an inner tub rotatably disposed within the outer tub and configured to accommodate laundry, a circulation path connected to the outer tub, a blower fan configured to circulate air between the outer tub and the circulation path, a heater configured to heat the air, a dry filter configured within the circulation path and removable from the circulation path for capturing foreign matter contained in the air, an air trap connected to a bottom of the outer tub, a water level sensor configured to detect air pressure within the air trap that varies in response to a water level within the outer tub and output a detection signal corresponding to the air pressure, a control unit, and an alarm unit. The control unit determines whether the dry filter is attached to the circulation path based on the detection signal output from the water level sensor when air is circulating between the outer tub and the circulation path due to operation of the blower fan, and, if it is determined that the dry filter is not attached to the circulation path, causes the alarm unit to issue an alarm indicating that the dry filter is not attached.

[0009] According to the washer-dryer of this aspect, if the user forgets to attach the drying filter to the circulation path, the user can be made aware of this by the notification unit. Moreover, since the washer-dryer is configured to determine whether the drying filter is attached to the circulation path using a water level sensor that detects the water level in the outer tub, costs can be reduced, unlike configurations that require a dedicated detector to detect the attachment or detachment of the drying filter.

[0010] In the washer-dryer of this aspect, the control unit may be configured to acquire the detection signal from the water level sensor when the inner tub is stopped, and determine whether or not the drying filter is attached to the circulation path based on the detection signal.

[0011] The above configuration prevents the air pressure in the air trap from becoming unstable due to the influence of wind pressure generated by the rotation of the inner tub, which in turn prevents the detection signal from becoming unstable, thereby enabling accurate determination of whether or not the drying filter is attached to the circulation path.

[0012] In the washer-dryer according to this aspect, when the control unit determines that the drying filter is not attached to the circulation path, the control unit may be configured to execute the drying process, in which laundry is dried using air heated by the heater and introduced into the inner tub, under operating conditions different from those when the drying filter is attached to the circulation path.

[0013] For example, if the control unit determines the drying rate of the laundry based on the temperature and humidity in the inner tub and ends the drying process when a predetermined drying rate is reached, the value to be compared with the temperature, etc. as the drying rate determination threshold can be changed. Also, for example, if the control unit ends the drying process when a predetermined drying time has elapsed, the drying time can be changed.

[0014] According to the above configuration, even if the volume of air circulating between the outer tub and the circulation path changes from the state when the drying filter is attached to the circulation path, it is possible to dry the laundry in the inner tub well.

[0015] When the above configuration is adopted, the control unit can further be configured to determine whether or not the drying filter is attached to the circulation path based on the detection signal when the operating conditions are changed and the drying process is being performed, and to change the operating conditions again if it determines that the drying filter is attached to the circulation path.

[0016] With this configuration, even if the volume of air circulating between the outer tub and the circulation path changes from the state when the drying filter is not attached to the circulation path, it is possible to dry the laundry in the inner tub well.

[0017] In the washer-dryer according to this aspect, the control unit may be configured to determine whether or not the drying filter is attached to the circulation path based on the detection signal when the operation of the blower fan is started during the drying process.

[0018] According to the above configuration, if the drying filter is left unattached, the user can be notified of the fact at an early stage when the drying process is started.

[0019] In the above configuration, the control unit may be further configured such that, if it determines that the drying filter is attached to the circulation path when the blower fan starts operating during the drying process, it determines whether or not the drying filter is attached to the circulation path based on the detection signal during the subsequent drying process.

[0020] With this configuration, even if the drying filter is removed from the circulation path during the drying process and then forgotten to be attached, the user can be notified of the fact that it has been left attached. [Effects of the Invention]

[0021] According to the present invention, it is possible to provide a washing / drying machine that can detect when a drying filter has been left in the circulation path and notify the user of this, while suppressing an increase in costs.

[0022] The effects and significance of the present invention will become more apparent from the following description of the embodiments, however, the following embodiment is merely an example of how the present invention can be put into practice, and the present invention is not limited to the following embodiment. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 is a side cross-sectional view showing the configuration of a washer / dryer according to an embodiment. [Figure 2] FIG. 2 is a front cross-sectional view showing an outer tub to which a water level detector is attached according to the embodiment. [Figure 3] FIG. 3 is a block diagram showing the configuration of a washer / dryer according to an embodiment. [Figure 4] FIG. 4 is a flowchart showing a control process executed by the control unit in the drying step according to the embodiment. [Figure 5] FIG. 5 is a flowchart showing a control process executed by the control unit in the subsequent drying step when it is determined that the second drying filter is not attached to the circulation path, according to the embodiment. [Figure 6] FIG. 6 is a flowchart showing a control process executed by the control unit in the subsequent drying step when it is determined that the second drying filter is attached to the circulation path, according to the embodiment. [Figure 7] FIG. 7 is a flowchart showing a control process executed by the control unit in the drying step according to the first modification. DETAILED DESCRIPTION OF THE INVENTION

[0024] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a washing / drying machine according to the present invention will be described below with reference to the drawings.

[0025] Fig. 1 is a side cross-sectional view showing the configuration of a washer / dryer 1. Fig. 2 is a front cross-sectional view showing outer tub 20 to which water level detection unit 60 is attached.

[0026] The washer-dryer 1 of this embodiment is a so-called drum-type washer-dryer. The washer-dryer 1 includes a rectangular housing 10. A circular loading opening 11 through which laundry is loaded is formed on the front of the housing 10. The loading opening 11 is covered by a door 12 that can be opened and closed.

[0027] An outer tub 20 having a substantially cylindrical shape is disposed within the housing 10. The outer tub 20 is elastically supported by a plurality of dampers 21 and springs 22. A horizontal-axis drum 23 is rotatably disposed within the outer tub 20. The drum 23 rotates around a horizontal axis. The drum 23 has a circular opening 23a on its front surface. The drum 23 may also rotate around an axis inclined relative to the horizontal direction. The drum 23 corresponds to the inner tub of the present invention.

[0028] The outer tub 20 has a circular opening 20a in front of the opening 23a of the drum 23. The outer tub 20 includes an annular packing 24 made of an elastic material provided on the periphery of the opening 20a. The packing 24 is connected to the periphery of the input port 11. The periphery of the closed door 12 comes into contact with the packing 24, and the space between the input port 11 and the door 12 is watertight.

[0029] A large number of dewatering holes 23b are formed on the inner peripheral surface of the drum 23. In addition, three baffles 25, each having a substantially triangular prism shape, are provided on the inner peripheral surface of the drum 23 at equal intervals in the circumferential direction.

[0030] A drive motor 30 is disposed behind the outer tub 20 to generate torque for rotating the drum 23. The drive motor 30 is, for example, an outer rotor DC brushless motor. During the washing, rinsing, and drying processes, the drive motor 30 rotates the drum 23 at a rotation speed at which the centrifugal force acting on the laundry inside the drum 23 is smaller than the gravity, causing the laundry to tumble. On the other hand, during the spin-drying process, the drive motor 30 rotates the drum 23 at a rotation speed at which the centrifugal force acting on the laundry inside the drum 23 is much larger than the gravity, causing the laundry to stick to the inner circumferential surface of the drum 23.

[0031] A tubular drain outlet 20b is formed at the bottom of the outer tub 20. A drain unit 40, which drains water from the outer tub 20, is connected to the drain outlet 20b. The drain unit 40 is composed of a drain valve 41, a drain hose 42, and a drain filter 43. The drain filter 43 is connected to the lower end of the drain outlet 20b. The drain valve 41 is provided downstream of the drain filter 43 and includes, for example, a valve and a torque motor for opening and closing the valve. The drain hose 42 is connected to the drain valve 41. When the drain valve 41 is opened, water stored in the outer tub 20 is discharged outside the machine through the drain outlet 20b, the drain filter 43, and the drain hose 42. Foreign matter such as lint is captured by the drain filter 43.

[0032] A water supply device 50 is disposed at the top of the housing 10. The water supply device 50 includes a first water supply valve 51, a second water supply valve 52, a first water supply hose 53, and a second water supply hose 54. The first water supply valve 51 and the second water supply valve 52 are configured as dual electromagnetic valves. One end of the first water supply hose 53 is connected to the first water supply valve 51, and the other end is connected to a water inlet 20c provided on the rear surface of the outer tub 20. The second water supply hose 54 has one end connected to the second water supply valve 52, and the other end connected to the water supply member 150.

[0033] When the first water supply valve 51 is opened, tap water from the water faucet flows through the first water supply hose 53 and is supplied from the water inlet 20c into the outer tub 20. When the second water supply valve 52 is opened, tap water flows through the second water supply hose 54 and is supplied to the water supply member 150.

[0034] The first water supply hose 53 may be connected to a detergent box that houses a detergent container. In this case, a water injection pipe that is connected to the detergent box and through which water flows via the detergent container may be connected to the upper front part of the outer tub 20. Alternatively, instead of the detergent box, an automatic dispenser that automatically dispenses liquid detergent or liquid fabric softener into the outer tub 20 may be provided. The automatic dispenser includes, for example, a water supply channel, a liquid agent tank that stores the liquid detergent or liquid fabric softener, and a pump that sends the liquid detergent or liquid fabric softener from the liquid agent tank into the water supply channel. In this case, as water from the first water supply hose 53 flows through the water supply channel, the liquid detergent or liquid fabric softener that has been discharged into the water supply channel is washed away by the water and supplied into the outer tub 20 via the water injection pipe.

[0035] The outer tub 20 is provided with a water level detection unit 60 for detecting the water level within the outer tub 20. The water level detection unit 60 includes an air trap 61 connected to a drain outlet 20b at the bottom of the outer tub 20, a water level sensor 62 located at the top of the outer tub 20, and a hose 63 connecting the air trap 61 and the water level sensor 62. The hose 63 is made of resin, and its lower end is connected to a connection port 61a at the top of the air trap 61, extends upward from the air trap 61, and its upper end is connected to an inlet 62a of the water level sensor 62. The water level sensor 62 is a pressure-type water level sensor that detects the air pressure within the air trap 61 to detect the water level within the outer tub 20, and outputs a frequency signal to the control unit 201 as a detection signal corresponding to the detected air pressure, i.e., the water level. In this embodiment, as the water level in the outer tub 20 increases and the air pressure in the air trap 61 increases, the value of the frequency signal output from the water level sensor 62, that is, the frequency value, decreases.

[0036] A drying device 100 is disposed in an upper portion of the housing 10 for drying the laundry in the drum 23. The drying device 100 includes a circulation path 110, a blower fan 120, a cooler 131, a heater 132, a first drying filter 140, a water supply member 150, a wiper mechanism 160, and a second drying filter 170.

[0037] The circulation path 110 is an air path through which air flows and is connected to the outer tub 20. The circulation path 110 includes a first duct 111, a fan casing 112, a second duct 113, a first connection hose 114, and a second connection hose 115. One end of the first duct 111 is connected to an exhaust port 20d provided on the back surface of the outer tub 20, and the other end is connected to an intake port of the fan casing 112 via the first connection hose 114. One end of the second duct 113 is connected to an exhaust port of the fan casing 112 via the second connection hose 115, and the other end is connected to an intake port 20e provided at the front end of the outer tub 20.

[0038] The blower fan 120 is, for example, a centrifugal fan, and includes a fan 121 arranged in the fan casing 112 and a fan motor 122 for driving the fan 121 to rotate. The blower fan 120 circulates air between the outer tub 20 and the circulation path 110. Air discharged from the outer tub 20 through the exhaust port 20d flows through the circulation path 110 via the first duct 111, the fan casing 112, and the second duct 113 in this order, and returns to the outer tub 20 through the intake port 20e.

[0039] The cooler 131 and the heater 132 are respectively disposed on the upstream and downstream sides of the second duct 113. The cooler 131 and the heater 132 are respectively configured by an evaporator and a condenser included in a heat pump device. The heat pump device includes a compressor 133 (see FIG. 3) and an expansion valve that configure a refrigeration circuit together with the evaporator and the condenser.

[0040] A low-temperature refrigerant flows inside the cooler 131. The cooler 131 cools the air flowing in the circulation path 110 by heat exchange with the low-temperature refrigerant, thereby dehumidifying the air.

[0041] A high-temperature refrigerant flows inside the heater 132. The heater 132 heats the dehumidified air flowing through the circulation path 110 by heat exchange with the high-temperature refrigerant.

[0042] The cooler 131 may be a water-cooled heat exchanger or the like, and the heater 132 may be a semiconductor heater or the like.

[0043] The first drying filter 140, the water supply member 150, and the wiper mechanism 160 are disposed in the circulation path 110 upstream of the blower fan 120 in the air flow.

[0044] The first drying filter 140 is disposed in the circulation path 110 so as to block the air flow path. A mesh is formed on the surface of the first drying filter 140, which is the capturing surface. The first drying filter 140 captures foreign matter such as lint and dust contained in the air discharged from the outer tub 20 using the capturing surface. The first drying filter 140 is fixed inside the circulation path 110 and cannot be removed from the circulation path 110. Therefore, the user cannot access the first drying filter 140 from the outside to perform cleaning or the like.

[0045] The water supply member 150 and the wiper mechanism 160 are intended to automatically clean the first drying filter 140 and remove trapped foreign matter. The water supply member 150 is disposed above the first drying filter 140 and causes water supplied from the second water supply valve 52 to flow over the surface of the first drying filter 140, washing away foreign matter adhering to the first drying filter 140. The wiper mechanism 160 includes a wiper 161 and an actuator 162. The wiper 161 is driven by the actuator 162 and moves back and forth over the surface of the first drying filter 140, thereby wiping off foreign matter adhering to the first drying filter 140.

[0046] The second drying filter 170 is disposed in the circulation path 110 between the blower fan 120 and the heater 132 and cooler 131 so as to block the air flow path. A mesh is formed on the surface of the second drying filter 170, which is the capture surface. The second drying filter 170 has finer mesh than the first drying filter 140. An opening 116, which serves as an insertion port for the second drying filter 170, is formed in the upper surface of the circulation path 110. The second drying filter 170 is inserted into the circulation path 110 through the opening 116 and can be removed upward from the circulation path 110. In other words, the second drying filter 170 is detachable from the circulation path 110. A handle 171 is attached to the upper end of the second drying filter 170 to be gripped when attaching or detaching the second drying filter 170 to or from the circulation path 110. The second drying filter 170 corresponds to the drying filter of the present invention.

[0047] An entrance 13 is formed in the top surface of the housing 10 at a position that overlaps in the vertical direction with the arrangement position of the second drying filter 170 in the circulation path 110. The entrance 13 is closed by an openable and closable lid 14. When cleaning the second drying filter 170, the user can open the lid 14 and take the second drying filter 170, which has been removed from the circulation path 110, out of the housing 10 through the entrance 13. Furthermore, the user can open the lid 14, put the cleaned second drying filter 170 into the housing 10 through the entrance 13, and attach it to the circulation path 110.

[0048] The lid portion 14 is not integrated with the second drying filter 170, and therefore the entrance / exit 13 can be closed regardless of whether the second drying filter 170 is attached to the circulation path 110. Therefore, although the lid portion 14 may be closed without the second drying filter 170 being attached, the user cannot check from the outside whether the second drying filter 170 is attached.

[0049] The drying device 100 includes a first temperature sensor 181 and a second temperature sensor 182. The first temperature sensor 181 is disposed upstream of the blower fan 120 in the circulation path 110 and detects the temperature of the air (wind) discharged from the outer tub 20 as the outlet temperature. The second temperature sensor 182 is disposed downstream of the heater 132 in the circulation path 110 and detects the temperature of the air (wind) introduced into the outer tub 20 after passing through the heater 132 as the inlet temperature. The outlet temperature is approximate to the temperature of the air in the outer tub 20, i.e., the drum 23, and can therefore be considered to be the temperature of the air in the drum 23.

[0050] FIG. 3 is a block diagram showing the configuration of the washer / dryer 1.

[0051] In addition to the above-described configuration, the washer-dryer 1 includes a control unit 201, a memory unit 202, an operation unit 203, a display unit 204, a sound output unit 205, a motor drive unit 206, a water supply drive unit 207, a drain drive unit 208, a fan drive unit 209, a compressor drive unit 210, and an actuator drive unit 211.

[0052] The operation unit 203 includes a power button for turning the power on and off, a course selection button for selecting an arbitrary course from a plurality of courses relating to operation such as washing operation, washing and drying operation, drying operation, etc., and a start button for starting and pausing operation. The operation unit 203 outputs an input signal to the control unit 201 according to the button operated by the user.

[0053] The display unit 204 includes a display such as a light-emitting element such as an LED or a liquid crystal panel, and displays the selected course, the progress of the operation, notifies of abnormalities, etc. in accordance with a control signal from the control unit 201. The abnormality notification includes a notification that the second drying filter 170 is not attached to the circulation path 110. The display unit 204 corresponds to the notification unit of the present invention.

[0054] The operation unit 203 and the display unit 204 may be configured as an operation display unit such as a touch panel.

[0055] The sound output unit 205 includes a speaker, and outputs sounds such as voice and alarm sounds from the speaker.

[0056] The water level sensor 62 detects the water level in the outer tub 20 and outputs a frequency signal corresponding to the detected water level as a detection signal to the control unit 201. The first temperature sensor 181 and the second temperature sensor 182 output temperature signals corresponding to the detected outlet temperature and inlet temperature, respectively, to the control unit 201.

[0057] The motor driving unit 206 drives the drive motor 30 in accordance with a control signal from the control unit 201. The motor driving unit 206 includes a rotation sensor that detects the rotation speed of the drive motor 30, an inverter circuit, etc., and adjusts the drive power so that the drive motor 30 rotates at the rotation speed set by the control unit 201.

[0058] The water supply driving unit 207 drives the first water supply valve 51 and the second water supply valve 52 in accordance with a control signal from the control unit 201. The drain driving unit 208 drives the drain valve 41 in accordance with a control signal from the control unit 201.

[0059] The fan driving unit 209 drives the fan motor 122 of the blower fan 120 in accordance with a control signal from the control unit 201. The compressor driving unit 210 drives the compressor 133 in accordance with a control signal from the control unit 201, and operates the cooler 131 and the heater 132. The actuator driving unit 211 drives the actuator 162 of the wiper mechanism 160 in accordance with a control signal from the control unit 201.

[0060] The storage unit 202 includes an EEPROM, a RAM, etc. Programs for executing various courses of operation are stored in the storage unit 202. The storage unit 202 also stores various parameters and various control flags used in executing these programs.

[0061] The control unit 201 includes a CPU, etc., and controls the display unit 204, sound output unit 205, motor drive unit 206, water supply drive unit 207, drain drive unit 208, fan drive unit 209, compressor drive unit 210, actuator drive unit 211, etc., based on signals from the operation unit 203, water level sensor 62, first temperature sensor 181, second temperature sensor 182, etc., in accordance with a program stored in the memory unit 202.

[0062] In the washer / dryer 1, various courses of washing / drying operation, washing operation, and drying operation are performed under the control of the control unit 201 based on the user's operation of the operation unit 203. In the washing / drying operation, the washing process, intermediate spin-drying process, rinsing process, final spin-drying process, and drying process are performed in order. In the washing operation, the washing process through the final spin-drying process are performed, but the drying process is not performed. In the drying operation, only the drying process is performed. In the washing / drying operation and washing operation, the rinsing process and intermediate spin-drying process may be performed two or more times depending on the course.

[0063] In the washing process, water containing detergent is filled in the outer tub 20 up to a predetermined washing water level, and laundry immersed in the water is tumbling inside the drum 23 as the drum 23 rotates forward and backward repeatedly. The detergent-containing water penetrates deep into the laundry, and the power of the detergent and the mechanical force of the tumbling remove dirt from the laundry.

[0064] In the rinsing process, with water stored in the outer tub 20 up to a predetermined rinsing water level, the drum 23 rotates forward and backward, tumbling the laundry inside the drum 23. This causes the detergent contained in the laundry to be expelled together with the water, rinsing the laundry.

[0065] In the intermediate and final spin-drying steps, the drive motor 30 rotates in one direction at high speed, causing the drum 23 to rotate in one direction at a speed at which the centrifugal force acting on the laundry inside the drum 23 is much greater than the force of gravity. The centrifugal force presses the laundry against the circumferential wall of the drum 23, causing it to be dewatered.

[0066] In the drying process, the operation of the blower fan 120 causes air, i.e., wind, to circulate between the outer tub 20 and the circulation path 110, and the operation of the heater 132 heats the wind introduced into the outer tub 20 to become warm air. Furthermore, the drum 23 rotates forward and backward, causing the laundry to tumble within the drum 23.

[0067] The warm air discharged from intake port 20e into drum 23 hits the tumbling laundry, drying the laundry. After removing moisture from the laundry, the warm air returns to circulation path 110 from exhaust port 20d. In circulation path 110, the warm air passes through cooler 131 before being heated by heater 132, and is dehumidified by cooler 131.

[0068] Foreign matter such as lint and dust from the laundry is taken into the circulation path 110 together with the warm air. The foreign matter is captured by the first drying filter 140 when the warm air passes through the first drying filter 140. Furthermore, small foreign matter that could not be captured by the first drying filter 140 is captured by the second drying filter 170 when the warm air passes through the second drying filter 170. This makes it difficult for foreign matter to adhere to the blower fan 120 located downstream of the first drying filter 140 or the cooler 131 and heater 132 located downstream of the second drying filter 170.

[0069] During drying, control unit 201 determines whether the laundry in drum 23 is dry or not. For example, the drying rate of the laundry in drum 23 is determined based on the outlet temperature detected by first temperature sensor 181 and the inlet temperature detected by second temperature sensor 182, and it is determined that the laundry is dry when a predetermined drying rate (for example, 100%) is reached.

[0070] The outlet temperature detected by the first temperature sensor 181, i.e., the temperature of the warm air discharged from the outer tub 20, remains substantially constant as long as the laundry in the drum 23 contains sufficient moisture and sufficient heat exchange occurs between the moisture and the warm air. Thereafter, the outlet temperature begins to rise as the laundry continues to dry and the moisture content decreases, making it difficult to exchange heat between the moisture and the warm air. Meanwhile, the inlet temperature detected by the second temperature sensor 182, i.e., the temperature of the warm air introduced into the outer tub 20, remains higher than the outlet temperature and remains substantially constant. Therefore, after the laundry has dried to a certain extent, the difference between the inlet and outlet temperatures decreases as the laundry drying rate increases.

[0071] The temperature difference between the inlet temperature and the outlet temperature when a predetermined drying rate is reached is determined in advance by conducting experiments or the like, and is set as a first specified value for determining the end of drying. Also, the outlet temperature when the predetermined drying rate is reached is determined in advance by conducting experiments or the like, and is set as a second specified value for determining the end of drying. It is determined that the predetermined drying rate has been reached when the temperature difference between the inlet temperature and the outlet temperature is equal to or less than the first specified value, or when the outlet temperature is equal to or greater than the second specified value. The first specified value and the second specified value are determination thresholds for determining whether the predetermined drying rate has been reached.

[0072] At the end of the drying process, the first drying filter 140 is automatically cleaned by the water supply member 150 and the wiper mechanism 160.

[0073] The detachable second drying filter 170 is periodically removed from the circulation path 110 and cleaned by the user. At this time, it is conceivable that the user will forget to attach the cleaned second drying filter 170 to the circulation path 110. If the washing / drying operation or the drying operation is performed without the second drying filter 170 attached, fine foreign matter that could not be captured by the first drying filter 140 during the drying process is likely to adhere to the cooler 131 and the heater 132 because it is not captured by the second drying filter 170. In addition, part of the air flowing from the blower fan 120 toward the cooler 131 and the heater 132 leaks out of the circulation path 110 through opening 116 where the second drying filter 170 is not inserted, reducing the amount of heated air introduced into drum 23, making it difficult for the laundry to dry.

[0074] Therefore, in the present embodiment, in the drying process, the control unit 201 determines whether or not the second drying filter 170 is attached to the circulation path 110 based on the detection signal output from the water level sensor 62 while air is circulating between the outer tub 20 and the circulation path 110 due to the operation of the blower fan 120. When the control unit 201 determines that the second drying filter 170 is not attached to the circulation path 110, it causes the display unit 204 to issue a notification indicating that the second drying filter 170 is not attached.

[0075] FIG. 4 is a flowchart showing the control process executed by the control unit 201 in the drying step.

[0076] Referring to FIG. 4, the control unit 201 starts the operation of the blower fan 120 and the heater 132 (S101). The blower fan 120 rotates at a preset rotation speed. Air circulates between the outer tub 20 and the circulation path 110. Furthermore, the temperature of the circulating air gradually increases. At the start of the drying process, the drain valve 41 is closed. This prevents the circulating air from leaking from inside the outer tub 20 downstream of the drain valve 41, i.e., outside the machine. When the heater 132 operates, the cooler 131 also operates.

[0077] Next, the control unit 201 acquires the frequency signal output from the water level sensor 62 (S102). Then, the control unit 201 determines whether the value of the frequency signal, i.e., the frequency value, is lower than a predetermined threshold value (S103).

[0078] When air is introduced from the circulation path 110 into the drum 23, i.e., the outer tub 20, the air pressure inside the outer tub 20 increases, and therefore the air pressure inside the air trap 61. The greater the volume of air introduced, the higher the air pressure inside the outer tub 20. When the second drying filter 170 is not attached to the circulation path 110, air leaks out from the opening 116, and therefore the volume of air introduced into the outer tub 20 is less than when the second drying filter 170 is attached to the circulation path 110. This reduces the air pressure inside the outer tub 20 and the air pressure inside the air trap 61, resulting in a higher frequency value of the frequency signal from the water level sensor 62.

[0079] The frequency value of the frequency signal output from the water level sensor 62 when the blower fan 120 rotates at a specified rotation speed without the second drying filter 170 attached to the circulation path 110 is obtained in advance through experiments or the like, and the threshold value is determined based on the frequency value. Therefore, if the second drying filter 170 is not attached to the circulation path 110, the frequency value of the frequency signal obtained from the water level sensor 62 in S102 will be higher than the threshold value.

[0080] It should be noted that the drum 23 is in a stopped state when the frequency signal is acquired from the water level sensor 62 in S102. This prevents the air pressure in the air trap 61 from becoming unstable due to the influence of wind pressure generated by the rotation of the drum 23, which in turn prevents the frequency signal from becoming unstable.

[0081] If the frequency value is not higher than the threshold value (S103: NO), the control unit 201 determines that the second drying filter 170 is attached to the circulation path 110, and starts the operation of the drum 23 by operating the drive motor 30 (S104). The drum 23 repeatedly rotates forward and backward at a rotation speed that tumbles the laundry. When the rotation direction is switched, the drum 23 pauses for a predetermined time.

[0082] On the other hand, if the frequency value is higher than the threshold value (S103: YES), the control unit 201 determines that the second drying filter 170 is not attached to the circulation path 110, and causes the display unit 204 to issue a notification indicating that the second drying filter 170 is not attached (S105). For example, the display unit 204 displays an error code corresponding to the fact that the second drying filter 170 is not attached. Furthermore, in response to a decrease in the amount of air introduced into the drum 23, the control unit 201 changes the determination threshold values ​​used to determine the drying efficiency, which is one of the operating conditions in the drying process, i.e., the first specified value and the second specified value, from the values ​​when the second drying filter 170 is attached to the circulation path 110 (S106).

[0083] In this embodiment, when the airflow rate of the circulating air decreases, the temperature of the heater 132 tends to increase due to the characteristics of the heat pump device, and the inlet and outlet temperatures of the air tend to increase. The inlet temperature also tends to be higher than the outlet temperature. Therefore, when a predetermined drying rate is reached, the temperature difference between the inlet and outlet temperatures increases, and the outlet temperature becomes higher, compared to when the airflow rate does not decrease. Therefore, when the second drying filter 170 is not attached to the circulation path 110, the control unit 201 sets the first specified value and the second specified value to be larger than the values ​​when the second drying filter 170 is attached to the circulation path 110.

[0084] After performing the processes of S105 and S106, the control unit 201 starts the operation of the drum 23 (S104).

[0085] The laundry tumbling in the drum 23 is exposed to the warm air introduced from the circulation path 110, so that the laundry gradually dries.

[0086] When the difference between the inlet temperature and the outlet temperature becomes equal to or less than the first specified value, or the outlet temperature becomes equal to or greater than the second specified value, and thus the drying rate of the laundry in drum 23 reaches a predetermined value (S107: YES), control unit 201 stops drum 23, heater 132, and blower fan 120 (S108). Thus, the drying process ends.

[0087] Incidentally, if the user notices a warning from the display unit 204 while the drying process is being carried out by changing the judgment threshold, which is an operating condition, based on the fact that the second drying filter 170 is not attached to the circulation path 110, the second drying filter 170 will be attached to the circulation path 110.

[0088] Therefore, when the control unit 201 changes the operating conditions and performs the drying process, it determines whether the second drying filter 170 is attached to the circulation path 110 based on the frequency signal from the water level sensor 62, and if it determines that the second drying filter 170 is attached to the circulation path 110, it changes the operating conditions again.

[0089] FIG. 5 is a flowchart showing the control process executed by the control unit 201 in the subsequent drying step when it is determined that the second drying filter 170 is not attached to the circulation path 110.

[0090] 5 is started when the operation of the drum 23 is started in S104 after the determination threshold value is changed in S106 of Fig. 4. The control process of Fig. 5 is executed in parallel with the control process of Fig. 4.

[0091] 5, the control unit 201 monitors whether the drum 23 has been temporarily stopped to switch between forward and reverse rotation (S201). When the drum 23 is temporarily stopped (S201: YES), the control unit 201 acquires the frequency signal output from the water level sensor 62 (S202). At this time, the drum 23 is stopped, so it is not affected by wind pressure generated by the rotation of the drum 23, and the frequency signal is less likely to become unstable.

[0092] The control unit 201 determines whether the frequency value of the frequency signal is higher than a predetermined threshold value (S203). If the frequency value is higher than the threshold value (S203: YES), the control unit 201 determines that the second drying filter 170 remains unattached to the circulation path 110, and waits for the drum 23 to resume rotation and then be temporarily stopped again (S204: YES → S201).

[0093] On the other hand, if the frequency value is not higher than the threshold value (S203: NO), the control unit 201 determines that the second drying filter 170 is attached to the circulation path 110, and causes the display unit 204 to stop displaying the notification indicating that the second drying filter 170 is not attached (S205). Furthermore, in response to an increase in the amount of air introduced into the drum 23, i.e., a return to a normal state, the control unit 201 again changes the determination threshold values ​​used to determine the drying efficiency, i.e., the first specified value and the second specified value, from the values ​​when the second drying filter 170 was not attached to the circulation path 110 (S206). That is, the control unit 201 returns the first specified value and the second specified value to the values ​​when the second drying filter 170 was attached to the circulation path 110.

[0094] When the process of S206 is performed, the control process of Fig. 5 ends. Also, when the drying step ends without proceeding to the processes of S205 and S206, the control process of Fig. 5 ends.

[0095] If the second drying filter 170 is attached to the circulation path 110 at the start of the drying process, it is conceivable that the user will interrupt operation during the drying process to clean the second drying filter 170. In such a case, the user may forget to return the second drying filter 170 to the circulation path 110 and resume operation.

[0096] Therefore, if the control unit 201 determines that the second drying filter 170 is attached to the circulation path 110 when the blower fan 120 starts operating during the drying process, it determines whether or not the second drying filter 170 is attached to the circulation path 110 during the subsequent drying process based on the water level signal from the water level sensor 62.

[0097] FIG. 6 is a flowchart showing the control process executed by the control unit 201 in the subsequent drying step when it is determined that the second drying filter 170 is attached to the circulation path 110.

[0098] When the operation of the drum 23 is started in S104 after it is determined in S103 of Fig. 4 that the frequency value is not higher than the threshold value, the control process of Fig. 6 is started. The control process of Fig. 6 is executed in parallel with the control process of Fig. 4.

[0099] 6, the control unit 201 monitors whether the drum 23 has been temporarily stopped to switch between forward and reverse rotation (S301). When the drum 23 has been temporarily stopped (S301: YES), the control unit 201 acquires a frequency signal output from the water level sensor 62 (S302). Then, the control unit 201 determines whether the frequency value of the frequency signal is higher than a predetermined threshold (S303).

[0100] If the frequency value is not higher than the threshold value (S303: NO), the control unit 201 determines that the second drying filter 170 remains attached to the circulation path 110, and waits for the drum 23 to resume rotation and then be temporarily stopped again (S304: YES → S301).

[0101] On the other hand, if the frequency value is higher than the threshold value (S303: YES), the control unit 201 determines that the second drying filter 170 is not attached to the circulation path 110, and causes the display unit 204 to issue a notification indicating that the second drying filter 170 is not attached (S305). Furthermore, the control unit 201 changes the first specified value and the second specified value, which are the determination threshold values, from the values ​​when the second drying filter 170 is not attached to the circulation path 110 (S306).

[0102] When the process of S306 is performed, the control process of Fig. 6 ends. Also, when the drying step ends without proceeding to the processes of S305 and S306, the control process of Fig. 6 ends.

[0103] Note that even after the second drying filter 170 becomes attached during the drying process and the determination threshold is changed again in S206 of the control process in Fig. 5, the control unit 201 executes the control process in Fig. 6. Furthermore, even after the second drying filter 170 becomes detached during the drying process and the determination threshold is changed in S306 of Fig. 6, the control unit 201 executes the control process in Fig. 5.

[0104] <Effects of the embodiment> According to this embodiment, the control unit 201 determines whether the second drying filter 170 is attached to the circulation path 110 based on a frequency signal, which is a detection signal output from the water level sensor 62, when air is circulating between the outer tank 20 and the circulation path 110 due to the operation of the blower fan 120, and if it determines that the second drying filter 170 is not attached to the circulation path 110, it causes the display unit 204 to issue a notification indicating that the second drying filter 170 is not attached.

[0105] According to this configuration, if the user forgets to attach the second drying filter 170 to the circulation path 110, the user can be made aware of this by a notification on the display unit 204. Moreover, since the water level sensor 62 for detecting the water level in the outer tub 20 is used to determine whether the second drying filter 170 is attached to the circulation path 110, costs can be kept low, unlike configurations in which a dedicated detector is provided for detecting the attachment or detachment of the second drying filter 170.

[0106] Furthermore, according to this embodiment, the control unit 201 acquires a frequency signal from the water level sensor 62 when the drum 23 is stopped, and determines whether or not the second drying filter 170 is attached to the circulation path 110 based on the frequency signal.

[0107] This configuration prevents the air pressure in the air trap 61 from becoming unstable due to the influence of wind pressure generated by the rotation of the drum 23, which in turn prevents the frequency signal from becoming unstable. Therefore, it becomes possible to accurately determine whether the second drying filter 170 is attached to the circulation path 110.

[0108] Furthermore, according to this embodiment, when the control unit 201 determines that the second drying filter 170 is not attached to the circulation path 110, the control unit 201 executes the drying process by changing the determination threshold value of the drying rate, which is an operating condition, from when the second drying filter 170 is attached to the circulation path 110.

[0109] With this configuration, even if the volume of air circulating between the outer tub 20 and the circulation path 110 changes from the state when the second drying filter 170 is attached to the circulation path 110, it is possible to dry the laundry in the drum 23 well.

[0110] Furthermore, according to this embodiment, when the control unit 201 is performing the drying process by changing the judgment threshold, which is an operating condition, it determines whether the second drying filter 170 is attached to the circulation path 110 based on the frequency signal from the water level sensor 62, and if it determines that the second drying filter 170 is attached to the circulation path 110, it changes the judgment threshold again.

[0111] With this configuration, even if the volume of air circulating between the outer tub 20 and the circulation path 110 changes from the state when the second drying filter 170 is not attached to the circulation path 110, the laundry in the drum 23 can be dried well.

[0112] Furthermore, according to this embodiment, when the blower fan 120 starts operating during the drying process, the control unit 201 determines whether the second drying filter 170 is attached to the circulation path 110 based on the frequency signal from the water level sensor 62.

[0113] According to this configuration, if the second drying filter 170 is left unattached, the user can be notified of this at an early stage at the start of the drying process.

[0114] Furthermore, according to this embodiment, if the control unit 201 determines that the second drying filter 170 is attached to the circulation path 110 when the blower fan 120 starts operating during the drying process, it determines whether the second drying filter 170 is attached to the circulation path 110 based on the frequency signal from the water level sensor 62 during the subsequent drying process.

[0115] According to this configuration, even if the second drying filter 170 is removed from the circulation path 110 during the drying process and then forgotten to be attached, the user can be notified of the fact that it has been left attached.

[0116] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications to the embodiments of the present invention are possible.

[0117] <Change example 1> In the above embodiment, in the drying process, after the operation of the blower fan 120, the heater 132 and the drum 23 is started, when the drying rate of the laundry in the drum 23 reaches a predetermined drying rate, the blower fan 120, the heater 132 and the drum 23 are stopped.

[0118] In contrast to this, in the first modification, when a predetermined drying time has elapsed in the drying step, the blower fan 120, the heater 132, and the drum 23 are stopped.

[0119] FIG. 7 is a flowchart showing the control process executed by the control unit 201 in the drying step according to the first modification.

[0120] In this modified example, when the frequency value is higher than the threshold value (S103: YES), the control unit 201 causes the display unit 204 to issue a notification indicating that the second drying filter 170 is not attached (S105), and then changes the drying time, which is one of the operating conditions in the drying step, from the time when the second drying filter 170 is attached to the circulation path 110 (S121). That is, the control unit 201 lengthens the drying time to accommodate the decrease in the amount of air introduced into the drum 23.

[0121] Thereafter, the control unit 201 starts the operation of the drum 23 (S104) and monitors whether the drying time has elapsed (S122). If the drying time has elapsed (S122: YES), the control unit 201 stops the drum 23, the heater 132, and the blower fan 120 (S108).

[0122] Furthermore, in this modified example, the control unit 201 also executes the control processes of FIGS. 5 and 6. However, in S206 in the control process of FIG. 5, the control unit 201 changes the drying time again. At this time, the drying time is not returned to the original time (the time when the second drying filter 170 was attached), but is made longer than the original time. The time added to the original time by this second change should be longer the longer the time the second drying filter 170 was not attached. Furthermore, in S306 in the control process of FIG. 6, the control unit 201 changes the drying time in the same manner as in S121 in FIG. 7.

[0123] The configuration of this modified example can also achieve the same effects as the above embodiment.

[0124] <Other change examples> In the drying process, when the drying rate of the laundry in drum 23 reaches a predetermined drying rate or when a predetermined drying time has elapsed, control unit 201 may stop blower fan 120, heater 132, and drum 23. In this case, based on the determination that second drying filter 170 is not attached to circulation path 110, both the determination threshold value for the drying rate and the drying time are changed.

[0125] Furthermore, in the drying step, the control unit 201 may change the rotation speed of the blower fan 120, which is one of the operating conditions, when it determines that the second drying filter 170 is not attached to the circulation path 110. That is, when the second drying filter 170 is not attached, the volume of air introduced into the drum 23 decreases, so the rotation speed of the blower fan 120 is increased to increase the volume of air.

[0126] Furthermore, a configuration may be adopted in which a removable second drying filter 170 is disposed upstream of the blower fan 120 in the circulation path 110, and the first drying filter 140, water supply member 150, and wiper mechanism 160 are disposed between the blower fan 120 and the heater 132 and cooler 131. In this configuration, if the second drying filter 170 is not attached to the circulation path 110, air outside the circulation path 110 is sucked in through the opening 116 as the blower fan 120 rotates, increasing the air volume. This increases the air pressure in the outer tub 20, and therefore the air pressure in the air trap 61. Therefore, in S103 of the control processing in FIG. 5, the control unit 201 determines whether the frequency value of the frequency signal acquired from the water level sensor 62 is lower than a threshold determined by experiment or the like. Then, when the frequency value is lower than the threshold value, the control unit 201 determines that the second drying filter 170 is not attached to the circulation path 110, and causes the display unit 204 to issue a notification indicating that the second drying filter 170 is not attached. Furthermore, when the temperature of the circulating air becomes difficult to increase due to the inclusion of outside air, the control unit 201 can change the determination threshold value for the dryness rate or change the drying time accordingly.

[0127] Furthermore, the washer / dryer 1 may be configured such that only a removable drying filter is disposed upstream of the blower fan 120 in the circulation path 110.

[0128] Furthermore, in the above embodiment, the notification that the second drying filter 170 is not attached may be made by an alarm sound or voice from the sound output unit 205 in addition to or instead of the display unit 204. In this case, the sound output unit 205 corresponds to the notification unit of the present invention.

[0129] Furthermore, in the drying process, the operation of the heater 132 may be started together with the operation of the drum 23, rather than together with the operation of the blower fan 120. That is, the operation of the heater 132 may be started after determining whether or not the second drying filter 170 is attached.

[0130] Furthermore, in the above embodiment, in the drying process, the drying rate of the laundry in the drum 23 is determined based on the temperature of the air in the outer tub 20. However, the drying rate of the laundry may be determined based on the humidity of the air in the outer tub 20. In this configuration, when the humidity in the outer tub 20 detected by the humidity sensor becomes lower than a threshold value, it can be determined that the predetermined drying rate has been reached.

[0131] Furthermore, in the above embodiment, the washer / dryer 1 is a drum-type washer / dryer having a horizontal-axis drum 23 inside the outer tub 20. However, the present invention can also be applied to a so-called vertical-type washer / dryer having a vertical-axis washing / spinning tub with a pulsator inside as an inner tub inside the outer tub.

[0132] In addition, the embodiments of the present invention can be modified in various ways as appropriate within the scope of the technical ideas set forth in the claims. [Explanation of symbols]

[0133] 10. Cabinet 20 Outer tank 23 Drum (inner tank) 61 Air Trap 62 Water level sensor 110 Circulation route 120 Blower fan 132 Heater 170 Second drying filter (drying filter) 201 Control Unit 204 Display unit (notification unit)

Claims

1. an outer tank disposed within the housing; an inner tub rotatably disposed within the outer tub and configured to accommodate laundry; a circulation path connected to the outer tank; a blower fan that circulates air between the outer tank and the circulation path; a heater disposed in the circulation path and configured to heat the air; a dry filter that is detachable from the circulation path and that is disposed in the circulation path and captures foreign matter contained in the air; an air trap connected to the bottom of the outer tank; a water level sensor that detects the air pressure in the air trap, which changes depending on the water level in the outer tub, and outputs a detection signal of a value corresponding to the air pressure; A control unit; a notification unit, The control unit determining whether the drying filter is attached to the circulation path based on the detection signal output from the water level sensor while air is circulating between the outer tub and the circulation path due to the operation of the blower fan; When it is determined that the dry filter is not attached to the circulation path, the notification unit is caused to issue a notification indicating that the dry filter is not attached. A washer-dryer characterized by the above.

2. The washing and drying machine according to claim 1, The control unit acquires the detection signal from the water level sensor when the inner tub is stopped, and determines whether the drying filter is attached to the circulation path based on the detection signal. This is a washing machine / dryer that is characterized by the above.

3. The washing and drying machine according to claim 1 or 2, When the control unit determines that the drying filter is not attached to the circulation path, the control unit executes a drying process of drying the laundry by using air heated by the heater and introduced into the inner tub under operating conditions different from those when the drying filter is attached to the circulation path. A washer-dryer characterized by the above.

4. The washing and drying machine according to claim 3, The control unit When the drying step is being performed under the changed operating conditions, a determination is made as to whether the drying filter is attached to the circulation path based on the detection signal. When it is determined that the drying filter is attached to the circulation path, the operating conditions are changed again. A washer-dryer characterized by the above.

5. The washing and drying machine according to claim 1 or 2, the control unit determines whether the drying filter is attached to the circulation path based on the detection signal when the operation of the blower fan is started in the drying step. A washer-dryer characterized by the above.

6. The washing and drying machine according to claim 5, When the control unit determines that the drying filter is attached to the circulation path at the start of operation of the blower fan in the drying process, the control unit determines whether the drying filter is attached to the circulation path based on the detection signal during the subsequent drying process. A washer-dryer characterized by the above.

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