Dryer

Abstract

The objective is to provide a drying machine that dries objects using an adsorbent that has the characteristic of releasing moisture at low temperatures. [Solution] The dryer 100 of this disclosure includes a heating unit 153 for heating air, a processing chamber 112 for drying an object to be dried, a circulating air passage 131 connected to the processing chamber so that air flowing out of the processing chamber 112 returns to the processing chamber 112, and an adsorbent material 139 disposed within the circulating air passage. The circulating air passage 131 is configured to define a first path through which air passes over the adsorbent material 139 and a second path through which air does not pass over the adsorbent material. The dryer 100 further includes a switching device 134 for switching the air circulation path.

Description

Technical Field

[0001] The present disclosure relates to a dryer for drying an object to be dried.

Background Art

[0002] Patent Document 1 discloses a dryer 900 shown in FIG. 12. The dryer 900 is configured to dry clothes as an object to be dried, and includes a processing chamber 910 for accommodating the clothes and a circulation air passage portion 920 through which air circulates. In the middle of the circulation air passage portion 92, a dehumidifying device 930 incorporating an adsorbent for adsorbing moisture contained in the air and a heater for heating the air is disposed. After the air is dehumidified and heated in the dehumidifying device 930, it flows into the processing chamber 910 through the circulation air passage portion 920. This air takes moisture from the clothes in the processing chamber 910 and then flows into the dehumidifying device 930 through the circulation air passage portion 920.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In Patent Document 1, silica gel or zeolite is used as the adsorbent. Silica gel and zeolite have a release characteristic of releasing moisture, but the temperature at which this release characteristic is exhibited is higher than the temperature of the air required to dry the clothes. Therefore, in the dryer 900 of Patent Document 1, the clothes can be dried at a temperature at which moisture is not released from the adsorbent. For this reason, the moisture released from the adsorbent does not flow into the processing chamber 910, and the clothes can be dried in the processing chamber 910.

[0005] However, it is sometimes preferable to use an adsorbent that has a release property that releases moisture at a temperature below the temperature required to dry the clothes. For example, in the case of an adsorbent whose adsorption capacity for moisture is restored by releasing moisture, the lower the amount of heat required to restore the adsorption capacity, the more it can contribute to saving energy in the dryer. However, if the adsorbent releases moisture at a temperature lower than the temperature required to dry the clothes, this moisture may return to the processing chamber 910 containing the items to be dried, and may hinder the drying of the items.

[0006] The present disclosure aims to provide a dryer that dries objects using an adsorbent that has the characteristic of releasing moisture at low temperatures. [Means for solving the problem]

[0007] The dryer in this disclosure is configured to dry an object to be dried. The dryer comprises a processing chamber for drying the object to be dried, a circulating air passage connected to the processing chamber so that air flowing out of the processing chamber returns to the processing chamber, an airflow generation unit that generates a circulating flow of air circulating in the processing chamber and the circulating air passage, a heating unit that heats the air circulating in the processing chamber and the circulating air passage toward a predetermined target temperature for drying the object to be dried, and an adsorbent disposed in the circulating air passage, which has the characteristic of adsorbing moisture in an adsorption temperature range lower than the target temperature and releasing moisture in a release temperature range including the target temperature. The circulating air passage is configured to define a first path through which air passes over the adsorbent and a second path through which air does not pass over the adsorbent. The dryer further comprises a switching device that switches the air circulation path so that air flows through the first path when the air is at a temperature within the adsorption temperature range, and air flows through the second path when the air is at a temperature within the release temperature range. [Effects of the Invention]

[0008] The aforementioned dryer can dry objects by utilizing an adsorbent that has the characteristic of releasing moisture at low temperatures. [Brief explanation of the drawing]

[0009] [Figure 1] Cross-sectional view of the dryer (first embodiment) [Figure 2] Schematic diagram of a dryer [Figure 3] Schematic diagram of a storage case containing the adsorbent material for a dryer. [Figure 4] Dryer control configuration diagram [Figure 5] Dryer control flowchart [Figure 6] Schematic diagram of other dryers [Figure 7] Schematic diagram of other dryers [Figure 8] Schematic diagram of other dryers [Figure 9] Flowchart for controlling the dryer (Second Embodiment) [Figure 10] Schematic diagram of other storage cases [Figure 11] Schematic diagram of other storage cases [Figure 12] Schematic diagram of a conventional dryer [Modes for carrying out the invention]

[0010] The first and second embodiments of the dryer will be described in detail below with reference to the drawings. However, unnecessary details may be omitted. For example, detailed explanations of already well-known matters or redundant explanations of substantially identical configurations may be omitted. This is to avoid the following explanation becoming unnecessarily verbose and to facilitate understanding for those skilled in the art. The accompanying drawings and the following explanation are provided to enable those skilled in the art to fully understand this disclosure and are not intended to limit the subject matter described in the claims.

[0011] (First Embodiment) Figure 1 is a schematic cross-sectional view of the dryer 100. This dryer 100 is configured not only to dry clothing or fabric products (for example, handkerchiefs, towels, curtains, and sheets) but also to wash them.

[0012] (Overall Structure of the Dryer) The dryer 100 includes a housing 110 formed with an inlet for loading the object to be dried, and a door portion 111 for opening and closing the inlet of the housing 110. Specifically, the inlet is formed in the front wall of the housing 110, and the door portion 111 is rotatably attached to the front wall of the housing 110. Various internal devices for performing a washing process, a rinsing process, a dehydration process, and a drying process are accommodated in the housing 110.

[0013] In the housing 110, a water tank 114 and a rotary drum 115 are arranged which form a processing chamber 112 for accommodating the object to be dried introduced through the inlet and drying the object to be dried. The water tank 114 has an opening 113 that opens toward the closed door portion 111, and the rotary drum 115 is held rotatably within the water tank 114. An opening 116 that opens in the same direction as the opening 113 of the water tank 114 is formed in the front end wall of the rotary drum 115. Further, a large number of small holes 117 are formed in the peripheral wall of the rotary drum 115. The object to be dried introduced through the inlet is accommodated within the rotary drum 115 through the openings 113 and 116 of the water tank 114 and the rotary drum 115.

[0014] The water tank 114 is provided for storing water in the washing process and the rinsing process. The water tank 114 is elastically supported by a suspension mechanism 118 fixed to the bottom wall of the housing 110.

[0015] In order to suppress leakage of water from the opening 113 of the water tank 114, a seal member 119 is provided at the opening 113 of the water tank 114. The seal member 119 is compressed by the door portion 111 when the door portion 111 closes the inlet.

[0016] At the upper part of the peripheral wall of the water tank 114, a water supply port 120 through which water flows in during the washing process and the rinsing process is provided. Further, a drain port 121 for draining the water used for washing and rinsing the drying object is provided at the lower part of the peripheral wall of the water tank 114. Since a large number of small holes 117 are formed in the rotary drum 115 in the water tank 114, the water supplied through the water supply port 120 can soak into the drying object in the rotary drum 115 through these small holes 117.

[0017] Also, in the drying process, in order to allow the inflow and outflow of the air for drying the drying object, an exhaust port 122 is formed at the upper part of the peripheral wall of the water tank 114, and an air supply port 123 is formed at the rear end wall of the water tank 114. In the drying process, the air flows into the processing chamber 112 from the air supply port 123 and is exhausted from the processing chamber 112 through the exhaust port 122. In the processing chamber 112, since a large number of small holes 117 are formed in the rotary drum 115, the air can flow into the rotary drum 115 through these small holes 117 and contact the clothes in the rotary drum 115.

[0018] A drive motor 124 for rotationally driving the rotary drum 115 is attached to the outer surface of the rear end wall of the water tank 114. The motor shaft of the drive motor 124 penetrates the rear end wall of the water tank 114 and is connected to the rotary drum 115. When the rotary drum 115 is rotationally driven by the drive motor 124, the drying object can be agitated in the rotary drum 115. The drive motor 124 is configured to be able to change the rotational speed of the rotary drum 115 under inverter control.

[0019] Above the water tank 114, a water supply unit 125 for supplying water to the drying object in the processing chamber 112 is provided. The water supply unit 125 includes a water supply path 126 piped above the water tank 114, a water supply valve 127 and a detergent box 128 provided in the water supply path 126.

[0020] The upstream end of the water supply path 126 is exposed on the outer surface of the housing 110 and is configured to be connectable to a hose (not shown) extending from a water tap. The downstream end of the water supply path 126 is connected to the water inlet 120 of the water tank 114.

[0021] The water supply valve 127 is configured to open and close the water supply path 126 and is positioned upstream of the detergent box 128 in the direction of water flow within the water supply path 126. The detergent box 128 is configured to contain detergent. The detergent box 128 is also configured to allow water to pass through it when the water supply valve 127 is opened.

[0022] A drainage path 129 is provided on the underside of the water tank 114 for draining water from the water tank 114. The drainage path 129 extends from the drain port 121 of the water tank 114 to the outside of the housing 110. The drainage path 129 is equipped with a drain valve 130 that opens and closes the drainage path 129. When the drain valve 130 opens the drainage path 129 while water has accumulated in the processing chamber 112, the water in the processing chamber 112 is drained through the drainage path 129.

[0023] Outside the water tank 114, a circulating air passage 131 is provided, connected to the air intake 123 and exhaust 122 of the water tank 114, to allow air flowing out of the treatment chamber 112 to return to the treatment chamber 112. Adsorbent material 139 is arranged inside the circulating air passage 131, as shown in Figure 2. The circulating air passage 131 is formed to define a first path through which air flowing out of the treatment chamber 112 returns to the treatment chamber 112 after passing through the adsorbent material 139, and a second path through which air flowing out of the treatment chamber 112 returns to the treatment chamber 112 without passing through the adsorbent material 139. The first path is shown by a dotted line in Figure 2. The second path is shown by a dashed line in Figure 2.

[0024] In detail, as shown in Figure 2, the circulating air passage section 131 has a main air passage section 133 that is connected to the exhaust port 122 and the intake port 123 to form an air circulation path, and an adsorbent material 139 is placed inside the main air passage section 133. The first path is formed by the main air passage section 133.

[0025] To form a second path through which air does not pass over the adsorbent 139, the circulating air passage section 131 further includes a secondary air passage section 132. The secondary air passage section 132 branches off from the main air passage section 133 upstream of the adsorbent 139 in the direction of airflow through the main air passage section 133, and is connected to the main air passage section 133 downstream of the adsorbent 139. The secondary air passage section 132 is piped in parallel with the portion of the main air passage section 133 where the adsorbent 139 is located. In this embodiment, in the portion where the main air passage section 133 and the secondary air passage section 132 are piped in parallel, the main air passage section 133 and the secondary air passage section 132 are located close to each other to the extent that heat transfer from the air flowing through the secondary air passage section 132 to the adsorbent 139 in the main air passage section 133 is permissible.

[0026] A switching device 134 is provided in the circulating air passage section 131 to switch the air circulation path between a first path and a second path. The switching device 134 has an opening / closing section 150 composed of three opening / closing valves 135 to 137 provided in the circulating air passage section 131, and a circulation control unit 151 that controls these opening / closing valves 135 to 137. The circulation control unit 151 is configured within a control circuit unit 138 provided on the upper part of the housing 110 shown in Figure 1, and controls the opening / closing section 150 to open one of the circulation paths of the first and second paths while closing the other circulation path. The control circuit unit 138 is electrically connected to an operation panel 157 provided on the upper part of the front wall of the housing 110 and operated by the user, and is configured to operate the dryer 100 in response to operations on the operation panel 157. For example, the operating mode of the dryer 100 can be specified by operating the operation panel 157.

[0027] As shown in Figure 2, the on-off valve 135 is positioned in the secondary air passage 132 to open and close the secondary air passage 132. On the other hand, the remaining on-off valves 136 and 137 are positioned downstream of the branching portion of the secondary air passage 132 from the main air passage 133, and upstream of the connection portion between the main air passage 133 and the secondary air passage 132, in the direction of airflow through the main air passage 133. Specifically, the on-off valve 136 is provided upstream of the adsorbent material 139 in the direction of airflow through the main air passage 133, and the on-off valve 137 is provided downstream of the adsorbent material 139. When the on-off valve 135 is opened while the on-off valves 136 and 137 are closed, the air flows through the second path. Conversely, when the on-off valve 135 is closed and the on-off valves 136 and 137 are opened, the air flows through the first path and passes through the adsorbent material 139.

[0028] The adsorbent 139 has adsorption properties that adsorb moisture contained in the air within a predetermined adsorption temperature range, and release properties that release moisture within a predetermined release temperature range higher than this adsorption temperature range. The adsorbent 139 can recover its adsorption capacity by releasing moisture.

[0029] The adsorbent 139 is configured to swell by adsorbing moisture from the air in the adsorption temperature range, and then, when it reaches the release temperature range, to contract and release liquid water (hereinafter referred to as "liquid water") into the liquid phase. Examples of such adsorbents include N-substituted acrylamide polymers (for example, N-isopropylacrylamide, poly(N-ethylacrylamide), poly(Nn-propylacrylamide), poly(N-cyclopropylacrylamide), poly(N,N-dimethylacrylamide), poly(N-ethyl-N-methylacrylamide), poly(N-methyl-Nn-propylacrylamide), poly(N-impropyl-N-methylacrylamide), poly(N,N-diethylacrylamide), poly(N-acryloylpyrrolidine), poly(N-acryloylpiperidine), poly(N-ethoxyethylacrylamide), poly(N-ethyl-N-methoxyethylacrylamide), and poly(N-methoxyethylacrylamide). Poly(N-ethoxypropylacrylamide), poly(N-impropoxypropylacrylamide), poly(N-methoxyethoxypropylacrylamide), poly(N-tetrahydrofurfurylacrylamide), poly(N-1-methyl-2-methoxyethylacrylamide), poly(N-1-methoxymethylpropylacrylamide), poly(CN-(2·2-dimethoxyethyl)-N-methylacrylamide), poly(N-(1,3-dioxolan-2-yl)-N-methylacrylamide), poly(N-8-acryloyl-1,4-dioxa-8-aza-spiro(4,5)decane), poly(N,N-dimethoxyethylacrylamide), poly(N-acryloylmorpholin), etc. can be used.

[0030] The release temperature range of the adsorbent 139 made of this material is lower than that of silica gel and zeolite. The predetermined target temperature (e.g., 60°C) set relative to the air temperature for drying the clothing to be dried falls within the release temperature range of the adsorbent 139. On the other hand, the adsorption temperature range of the adsorbent 139 is lower than this target temperature. The adsorbent 139 described above can exhibit adsorption capacity within the range of normal temperature (5°C to 35°C).

[0031] To prevent the adsorbent material 139 from being carried away by the airflow in the main air passage 133, the adsorbent material 139 is housed in a containment case 140 fixed to the main air passage 133. As shown in Figure 3, this containment case 140 has a roughly cylindrical case body 141. An inlet port 142, an outlet port 143, and a drainage port 144 protrude from the case body 141.

[0032] The inlet port 142 is connected to the portion of the main air passage 133 that is upstream of the housing case 140 in the direction of airflow through the main air passage 133. The inlet port 142 forms an inlet 145 that extends substantially horizontally from one end face of the case body 141, and air can flow into the case body 141 through the inlet 145.

[0033] The outflow port 143 and drainage port 144 protrude from the peripheral wall of the case body 141 near the other end face of the case body 141. The outflow port 143 extends upward from the case body 141 and forms an upward-opening outlet 146. The portion of the main air duct 133 that is downstream of the housing case 140 in the direction of airflow through the main air duct 133 is connected to the outflow port 143. Air that flows into the case body 141 through the inlet 145 of the inflow port 142 flows out through the outlet 146 of the outflow port 143.

[0034] The drain port 144 extends downward from the case body 141 and forms a downward-opening drain outlet 147. The drain port 144 is provided to allow the liquid seeping from the adsorbent 139 to drain from the case body 141, and a drain tube (not shown) can be attached to the drain port 144 to guide this liquid outside the dryer 100.

[0035] As shown in Figure 2, the circulating air passage section 131 is equipped with a warming section 148 for warming the air inside the processing chamber 112. This warming section 148 includes an airflow generation section 152 that generates a circulating airflow through the circulating air passage section 131, a heating section 153 that heats the air, and a warming control section 154 that controls the airflow generation section 152 and the heating section 153. The warming control section 154 is configured within the control circuit section 138 shown in Figure 1 and operates and stops the airflow generation section 152 and the heating section 153. Furthermore, as shown in Figure 2, the processing chamber 112 is equipped with a temperature detection section 155 that detects the temperature of the air inside the processing chamber 112, and the warming control section 154 controls the heating section 153 so that the air temperature approaches the target temperature based on the temperature detected by the temperature detection section 155.

[0036] The airflow generator 152 is located near the exhaust port 122 of the processing chamber 112 and draws air out of the processing chamber 112 through the exhaust port 122. For example, a sirocco fan may be used as the airflow generator 152. The airflow generated by the airflow generator 152 is sent to the processing chamber 112 by the airflow generator 152 so that it flows through a first or second path and returns to the processing chamber 112 through the air intake port 123. A heating unit 153 is located near the air intake port 123, and the air flowing through the first or second path is heated by the heating unit 153 just before it flows into the processing chamber 112.

[0037] As shown in Figure 2, the circulating air passage 131 is further provided with a dehumidifying section 156 that cools the air and causes condensation. The dehumidifying section 156 is located downstream of the connection between the main air passage 133 and the sub-air passage 132, and upstream of the heating section 153, in the direction of airflow through the main air passage 133. When the first path is open, air that has passed through the adsorbent 139 in the main air passage 133 flows into the dehumidifying section 156. When the second path is open, air that has passed through the sub-air passage 132 flows into the dehumidifying section 156. The dehumidifying section 156 and the heating section 153 may constitute a heat pump device that exchanges heat with each other. In this case, higher energy efficiency can be obtained compared to when a heater is used as the heating section 153. That is, power saving of the dryer 100 can be achieved. Note that if there is no problem with energy efficiency, a heater may be used as the heating section 153.

[0038] (Control structure of a dryer) The control circuit unit 138 shown in Figure 1 is configured to control the operation of the dryer 100. As shown in Figure 4, the control circuit unit 138 has a main control unit 158 ​​in addition to the circulation control unit 151 and warm air control unit 154 described above.

[0039] The main control unit 158 ​​is configured to control the drive motor 124, water supply valve 127, and drain valve 130 according to a program corresponding to the operating mode specified by operation on the control panel 157, in order to sequentially execute the washing, rinsing, and dewatering processes. After the dewatering process, the main control unit 158 ​​is configured to control the dehumidification unit 156 and the drive motor 124 to execute the drying process. At the start of the drying process, the main control unit 158 ​​notifies the circulation control unit 151 and the warm air control unit 154 of the start of the drying process.

[0040] (Operation of the main control unit from the washing process to the dewatering process) During the washing process, the main control unit 158 ​​closes the drain valve 130 and opens the water supply valve 127 so that an amount of water corresponding to the amount of material to be dried is stored in the processing chamber 112. Then, with water stored in the processing chamber 112, the main control unit 158 ​​operates the drive motor 124 to agitate the material to be dried in the processing chamber 112.

[0041] During the rinsing process, the main control unit 158 ​​operates the drive motor 124 while controlling the water supply valve 127 and the drain valve 130 to agitate the items to be dried in the processing chamber 112, so that water is repeatedly stored in the processing chamber 112 and drained from the processing chamber 112. During the dewatering process, the main control unit 158 ​​closes the water supply valve 127 and opens the drain valve 130 to discharge water from the processing chamber 112. The main control unit 158 ​​then operates the drive motor 124 to rotate the rotating drum 115 at high speed. The centrifugal force generated by the rotation of the rotating drum 115 causes water to be separated from the clothes by centrifugal force.

[0042] When the dewatering process is complete, the main control unit 158 ​​starts the dehumidifying unit 156 while controlling the drive motor 124 so that the rotation speed of the rotating drum 115 decreases from the rotation speed of the rotating drum 115 during the dewatering process. The main control unit 158 ​​then notifies the circulation control unit 151 and the warm air control unit 154 that the drying process has begun. Upon receiving this notification, the warm air control unit 154 starts controlling the airflow generation unit 152 and the heating unit 153, and the circulation control unit 151 starts controlling the opening / closing unit 150.

[0043] (Operation of the dryer during the drying process) The dryer 100 operates in the drying process as shown in Figure 5. Specifically, when the warm air control unit 154 receives notification from the main control unit 158 ​​that the drying process has started, it activates the airflow generation unit 152 and the heating unit 153 (step S110). At this time, the temperature detected by the temperature detection unit 155 is lower than a predetermined switching temperature. This switching temperature is set to a value higher than the adsorption temperature range of the adsorbent material 139 and lower than the release temperature range. When the temperature detected by the temperature detection unit 155 is lower than this switching temperature, the circulation control unit 151 opens the on-off valves 136 and 137 provided in the main air passage 133 so that air flows through the first path. At this time, the on-off valve 135 provided in the secondary air passage 132 is closed (step S120). In this case, the air passes through the adsorbent material 139, and the moisture in the air is adsorbed by the adsorbent material 139.

[0044] As the air flows through the first path, it passes through the heating unit 153, so the temperature of the air detected by the temperature detection unit 155 gradually rises. If the air reaches the release temperature range while flowing through the first path, the adsorbent 139 may also reach the release temperature range. Under these temperature conditions, water will seep out from the adsorbent 139. This water may evaporate into the air flowing through the first path and flow into the processing chamber 112. In this case, the water evaporated into the air may adhere to the object to be dried in the processing chamber 112, potentially reducing the drying efficiency of the object.

[0045] To prevent such a decrease in drying efficiency, the circulation control unit 151 controls the opening / closing unit 150 so that the air circulation path switches from the first path to the second path before the air temperature reaches the release temperature range. Specifically, when the temperature detection unit 155 detects a temperature above the aforementioned switching temperature (step S130: Yes), the circulation control unit 151 performs control to switch the air circulation path (step S140). That is, the circulation control unit 151 closes the opening / closing valves 136 and 137 provided in the main air passage 133, while opening the opening / closing valve 135 provided in the secondary air passage 132.

[0046] Furthermore, the switching temperature used to determine the switching of the air circulation path is set to a value higher than the adsorption temperature range of the adsorbent 139. Therefore, before the temperature detection unit 155 detects that the air temperature is higher than this switching temperature (step S130: No), the air temperature, and consequently the temperature of the adsorbent 139, is at the temperature within the adsorption temperature range.

[0047] When the temperature of the adsorbent 139 is within the adsorption temperature range, the adsorbent 139 adsorbs moisture contained in the air flowing through the first path and swells within the containment case 140. As a result, the humidity of the air decreases as the air passes through the adsorbent 139.

[0048] As this air passes through the dehumidification unit 156, the moisture contained in the air condenses in the dehumidification unit 156, further reducing the humidity of the air. This air is then heated by the heating unit 153 and flows into the processing chamber 112. As a result, the objects to be dried in the processing chamber 112 are exposed to air that has been heated to a certain extent and whose humidity has been reduced. Consequently, the moisture contained in the objects to be dried evaporates into the air. The air that has removed moisture from the objects to be dried is then drawn out by the airflow generation unit 152 into the circulating air passage unit 131 and flows again through the first path.

[0049] When the air circulation path is switched from the first path to the second path, the air no longer passes through the adsorbent 139. However, since the air passes through the dehumidifier 156, the humidity of the air may decrease due to condensation in the dehumidifier 156. This air is then heated in the heating unit 153 and flows into the processing chamber 112, so the object to be dried is exposed to high-temperature, low-humidity air. As a result, the moisture contained in the object to be dried evaporates into the air, accelerating the drying of the object. Due to the increase in saturated water vapor content caused by heating in the heating unit 153 and the reduction in humidity due to condensation in the dehumidifier 156, the object to be dried can be dried in a short time.

[0050] Even after the air circulation path is switched to the second path, the heating unit 153 continues to heat the air, so the air temperature gradually rises from the switching temperature towards the target temperature (Step S150: No). Then, when the air temperature detected by the temperature detection unit 155 exceeds the target temperature (Step S150: Yes), the warm air control unit 154 controls the heating unit 153 so that the air temperature remains near the target temperature (Step S160).

[0051] While air flows through the second path, the adsorbent 139 can reach the release temperature range due to heat transfer from the air. That is, since the portion of the main air passage 133 where the adsorbent 139 is located is near the secondary air passage 132 which forms the second path, the adsorbent 139 can receive heat from the air flowing through the second path. When the adsorbent 139 reaches the release temperature range, water seeps out of the adsorbent 139, and the adsorbent 139 contracts. At this time, since the on-off valves 136 and 137 on the upstream and downstream sides of the adsorbent 139 are closed, the water seeped out of the adsorbent 139 is not exposed to the air circulating in the circulating air passage 131 and the treatment chamber 112, but is drained through the outlet 147 of the containment case 140. As a result of the release of water from the adsorbent 139, the adsorption capacity of the adsorbent 139 is restored.

[0052] The drying process ends when predetermined termination conditions are met (step S170). For example, the drying process may end when a predetermined length of time has elapsed since the temperature of the air detected by the temperature detection unit 155 exceeded the target temperature. In response to the end of the drying process, the main control unit 158 ​​stops the drive motor 124 and the dehumidification unit 156, and the warm air control unit 154 stops the heating unit 153 and the airflow generation unit 152. At this time, the circulation control unit 151 may keep the on-off valves 136 and 137 provided in the main air passage 133 closed. In this case, even if condensation occurs in the circulation air passage 131 when the dryer 100 is not in use, the on-off valves 136 and 137 can prevent the water generated in the circulation air passage 131 from coming into contact with the adsorbent 139. Therefore, the adsorbent 139 can remain almost water-free until the drying process is performed again, and can exert its adsorption capacity in the next drying process.

[0053] In the dryer 100 shown in Figures 1 to 5, the adsorption capacity of the adsorbent 139 can be restored by applying a lower amount of heat to the adsorbent 139 compared to cases where silica gel or zeolite is used to adsorb moisture contained in the air. That is, the adsorbent 139 used in the dryer 100 of this embodiment contracts when it reaches the release temperature range, and releases the adsorbed moisture by seeping out liquid water, so the amount of heat required for release is only the sensible heat. On the other hand, silica gel and zeolite release the adsorbed moisture by evaporation, so in addition to the sensible heat for temperature rise, latent heat of vaporization is also required, and a large amount of heat is needed to release the adsorbed moisture. Therefore, the adsorbent 139 of this embodiment does not evaporate the adsorbed moisture and can restore its adsorption capacity with a small amount of heat, thus contributing to power saving of the dryer 100.

[0054] In the dryer 100 shown in Figures 1 to 5, in order to prevent the water released from the adsorbent 139 from flowing into the processing chamber 112, the dryer 100 is configured to switch the air circulation path from the first path to the second path before the adsorbent 139 reaches the temperature of the release temperature range. When air is flowing through the second path, the adsorbent 139 is not exposed to this air, so the water seeping out from the adsorbent 139 does not evaporate into this air. As a result, the drying process of the object to be dried in the processing chamber 112 can be prevented from being hindered by the water seeping out from the adsorbent 139.

[0055] The dryer 100 shown in Figure 2 has two on-off valves 136 and 137 in the main air passage 133. However, if condensation does not occur in the circulating air passage 131 when the dryer 100 is not in use, one of these on-off valves 136 and 137 may be omitted.

[0056] The dehumidifying section 156 of the dryer 100 shown in Figure 2 is a single section, and is provided so that both the air flowing through the first path and the air flowing through the second path can pass through it. Alternatively, as shown in Figure 6, two dehumidifying sections 156 may be provided in the circulating air passage section 131. For example, if these dehumidifying sections 156 are arranged as shown in Figure 6, the air flowing through the first path and the air flowing through the second path can pass through separate dehumidifying sections 156. In this case, the dehumidifying section 156 that dehumidifies the air flowing through the first path may be at a higher temperature than the dehumidifying section 156 that dehumidifies the air flowing through the second path. In this case, since the cooling of the air in the dehumidifying section 156 that dehumidifies the air flowing through the first path is suppressed, the time it takes for the air temperature to reach the target temperature can be shortened. Note that if the air can be sufficiently dehumidified by the adsorbent 139, the dehumidifying section 156 that dehumidifies the air flowing through the first path may be omitted.

[0057] As shown in Figure 7, the dehumidifying unit 156 may be provided upstream of the branching point of the secondary air passage from the main air passage 133 in the direction of airflow through the main air passage 133. In this case, when the air circulation path is set to the first path, some of the moisture contained in the air is removed by the dehumidifying unit 156 before the air passes through the adsorbent material 139. As a result, the amount of moisture adsorbed by the adsorbent material 139 is less likely to reach the maximum amount of moisture that the adsorbent material 139 can adsorb.

[0058] Furthermore, if the dehumidifier 156 is provided upstream of the branching point of the secondary air passage from the main air passage 133 in the direction of airflow through the main air passage 133, an additional temperature detection unit 149 may be placed between the dehumidifier 156 and the on-off valve 136, as shown in Figure 8. In this case, the determination process for switching the opening and closing of the first and second paths (step S130 in Figure 5) can be performed based on the temperature detected by the additional temperature detection unit 149. Then, the control after the first path is closed and the second path is opened (from step S150 onward) can be performed based on the temperature detected by the temperature detection unit 155 provided in the processing chamber 112. In this case, since the determination process for switching the opening and closing of the first and second paths is performed based on the temperature of the air after passing through the dehumidifier 156, the switching of the opening and closing of the first and second paths can be performed with higher accuracy.

[0059] The temperature detection unit 155 of the dryer 100 shown in Figure 2 detects the temperature of the air inside the processing chamber 112. Alternatively, the temperature detection unit 155 may be located in the circulating air passage 131 to detect the temperature of the air flowing from the heating unit 153 toward the air intake 123. Or, the temperature detection unit 155 may be located in the circulating air passage 131 near the exhaust port 122 to detect the temperature of the air drawn out by the airflow generation unit 152 from the exhaust port 122.

[0060] As described above, the dryer 100 according to one aspect of the above embodiment is configured to dry an object to be dried. The dryer 100 is configured to dry an object to be dried. The dryer 100 comprises a processing chamber 112 for drying an object to be dried, a circulating air passage 131 connected to the processing chamber 112 so that air flowing out of the processing chamber 112 returns to the processing chamber 112, an airflow generating unit 152 that generates a circulating flow of air circulating in the processing chamber 112 and the circulating air passage 131, a heating unit 153 that heats the air circulating in the processing chamber 112 and the circulating air passage 131 toward a predetermined target temperature for drying the object to be dried, and an adsorbent 139 disposed in the circulating air passage 131 which has the characteristic of adsorbing moisture in an adsorption temperature range lower than the target temperature and releasing moisture in a release temperature range including the target temperature. The circulating air passage section 131 is configured to define a first path through which air passes over the adsorbent material 139 and a second path through which air does not pass over the adsorbent material 139. The dryer 100 further includes a switching device 134 that switches the air circulation path so that air flows through the first path when the air is at a temperature within the adsorption temperature range, and air flows through the second path when the air is at a temperature within the release temperature range.

[0061] In the above configuration, when the air is heated by the heating unit 153 to a high temperature at or close to the target temperature, this air is introduced into the processing chamber 112, and the moisture from the material to be dried is absorbed by the air. As a result, the drying of the material to be dried is promoted. Even before such a high temperature state is reached, the adsorbent 139 is used to promote the drying of the material to be dried.

[0062] In other words, for a while after heating of the air begins, the temperature of the air may be within the adsorption temperature range, which is lower than the target temperature. When the air, which is at a temperature within the adsorption temperature range, passes through the adsorbent 139, the adsorbent 139 also reaches a temperature within the adsorption temperature range, and the adsorbent 139 can adsorb the moisture contained in this air. In other words, the air is dehumidified by the adsorbent 139. When this dehumidified air is introduced into the processing chamber 112, drying of the object to be dried is promoted. That is, when air at a temperature within the adsorption temperature range is introduced into the processing chamber 112 through the first path where the adsorbent 139 is provided, drying of the object to be dried is promoted.

[0063] When the air is further heated by the heating unit 153, the temperature of the air may reach a temperature within the release temperature range. If such air continues to flow through the first path, the temperature of the adsorbent 139 will also reach a temperature within the release temperature range, and moisture may be released from the adsorbent 139 into the air. When this air flows into the processing chamber 112, the drying of the object to be dried may be hindered by the moisture released from the adsorbent 139.

[0064] To avoid such a situation, the switching device 134 switches the air circulation path so that air flows through the second path when the air is at the temperature within the release temperature range. In this state, the air circulates without passing through the adsorbent 139, so that moisture released from the adsorbent 139 does not hinder the drying of the object to be dried.

[0065] In the above configuration, the switching device 134 may be configured to switch the circulation path from the first path to the second path on the condition that the air has been heated to a predetermined switching temperature set to a value lower than the discharge temperature range.

[0066] In the configuration described above, when the air is heated to the switching temperature, the air circulation path is switched from the first path to the second path. Since this switching temperature is set to a value lower than the release temperature range, air that is at a temperature within the release temperature range is prevented from passing through the adsorbent 139.

[0067] In the above configuration, the dryer 100 may further include a temperature detection unit 155 for detecting the temperature of the air in the processing chamber 112 or the circulating air passage 131. The switching device 134 may include an opening / closing unit 150 that opens one of the first and second paths while closing the other path, and a circulation control unit 151 that controls the opening / closing unit 150 so that the first path is opened and the second path is closed when the temperature detected by the temperature detection unit 155 is lower than the switching temperature. The circulation control unit 151 may also control the opening / closing unit 150 so that the first path is closed and the second path is opened when the temperature detected by the temperature detection unit 155 is higher than the switching temperature.

[0068] In the above configuration, when the temperature detected by the temperature detection unit 155 rises above the switching temperature, the opening / closing unit 150 changes from a state where the first path is open and the second path is closed to a state where the second path is open and the first path is closed. As a result, the air returns to the processing chamber 112 without passing through the adsorbent 139, thus preventing the drying of the object to be dried in the processing chamber 112 from being hindered by moisture released from the adsorbent 139.

[0069] In the above configuration, the dryer 100 may further include a dehumidifying unit 156 that dehumidifies the air so as to cool the air flowing through the second path and cause condensation. The heating unit 153 may be arranged in the circulating air passage 131 to heat the air that has been dehumidified by the dehumidifying unit 156.

[0070] In the configuration described above, air in the processing chamber 112 removes moisture from the object to be dried, thereby drying the object. While this air flows through the second path, the moisture contained in this air condenses in the dehumidification unit 156. At this time, the air is cooled by the dehumidification unit 156, but this air is then heated by the heating unit 153, so the saturated water vapor content of this air increases. As air with a high saturated water vapor content and low humidity flows into the processing chamber 112, the drying of the object to be dried in the processing chamber 112 is accelerated. Since the humidity of the air is reduced not only by the adsorbent 139 but also by the dehumidification unit 156, the object to be dried can be dried in a short time.

[0071] In the above configuration, the dryer 100 may further include a dehumidifying unit 156 that dehumidifies the air so as to cool the air flowing through the first path and cause condensation. The heating unit 153 may be arranged in the circulating air passage 131 to heat the air that has been dehumidified by the dehumidifying unit 156.

[0072] In the above configuration, air in the processing chamber 112 removes moisture from the object to be dried, thereby drying the object. While this air flows through the first path, the moisture contained in this air is adsorbed by the adsorbent 139, but some moisture may not be adsorbed by the adsorbent 139. To reduce such moisture, a dehumidifier 156 is provided in the above configuration. If the dehumidifier 156 is located upstream of the adsorbent 139 in the direction of airflow, moisture in the air condenses in the dehumidifier 156 before the air flows to the adsorbent 139. In this case, the amount of moisture in the air passing through the adsorbent 139 is reduced, thus reducing the amount of moisture that cannot be adsorbed by the adsorbent 139. Conversely, if the dehumidifier 156 is located downstream of the adsorbent 139 in the direction of airflow, moisture that was not adsorbed by the adsorbent 139 may condense in the dehumidifier 156. In this way, since the air from which moisture has been removed by the adsorbent 139 and the dehumidifier 156 is heated by the heating unit 153, high-temperature and low-humidity air can flow into the processing chamber 112. Since the humidity of the air is reduced not only by the adsorbent 139 but also by the dehumidifier 156, the object to be dried can be dried in a short time.

[0073] In the above configuration, the adsorbent 139 may be configured to recover its adsorption capacity for adsorbing moisture by releasing moisture when it reaches the temperature in the release temperature range. The circulating air passage 131 may be configured to allow the adsorbent 139 to reach the temperature in the release temperature range due to heat transfer from the air flowing in the second path to the adsorbent 139 in the first path.

[0074] In the above configuration, the heating unit 153 heats the air toward the target temperature. When the air reaches the target temperature or a temperature close to it, the saturated water vapor content of the air increases, promoting the drying of the material to be dried in the processing chamber 112. At this time, the air flows through the second path, and the heat from this air is transferred to the adsorbent 139 in the first path. As a result of this heat transfer, the adsorbent 139 can reach a temperature within the release temperature range. Under these temperature conditions, moisture is released from the adsorbent 139, and the adsorption capacity of the adsorbent 139 is restored. Therefore, while the material to be dried is being dried with air at or close to the target temperature, moisture can be released from the adsorbent 139, restoring its adsorption capacity. Since the adsorption capacity of the adsorbent 139 is restored using the amount of heat required to dry the material, it is not necessary to add additional heat to restore the adsorption capacity of the adsorbent 139. Therefore, power saving of the dryer 100 can be achieved.

[0075] (Second Embodiment) In the first embodiment of the dryer 100, the adsorbent 139 reaches the release temperature range due to heat transfer from the air flowing through the second path. However, it is assumed that the temperature of the adsorbent 139 does not reach the release temperature range due to heat transfer from the air flowing through the second path. In this case, the dryer 100 may operate as shown in Figure 9 after the completion of the drying process.

[0076] In the first embodiment, the warm air control unit 154 of the dryer 100 stops both the heating unit 153 and the airflow generation unit 152 when the drying process is completed. However, in the second embodiment, the warm air control unit 154 of the dryer 100 stops only the heating unit 153 (step S210). That is, in the dryer 100 of the second embodiment, the airflow generation unit 152 continues to operate even after the drying process is completed. At this time, the temperature of the air has risen to a certain extent due to the heating by the heating unit 153 before the end of the drying process. In other words, the air is at a temperature close to the target temperature.

[0077] Approximately simultaneously with the warm air control unit 154 stopping the heating unit 153, the circulation control unit 151 switches the air circulation path from the second path to the first path (step S220). That is, the circulation control unit 151 closes the on-off valve 135 provided in the sub-air passage 132 and opens the on-off valves 136 and 137 provided in the main air passage 133. As a result, air at a temperature close to the target temperature passes through the adsorbent 139. Therefore, the adsorbent 139 is exposed to air at a temperature close to the target temperature, and the heat from this air raises the temperature of the adsorbent 139. As a result, the adsorbent 139 can reach a temperature within the release temperature range.

[0078] When the adsorbent 139 reaches the release temperature range, the moisture adsorbed by the adsorbent 139 before the end of the drying process seeps out of the adsorbent 139. The liquid seeping out of the adsorbent 139 flows down from the containment case 140 through the downward-facing outlet 147 shown in Figure 3 due to gravity. On the other hand, since the air temperature is relatively high, it flows out of the containment case 140 through the upward-facing outlet 146. In other words, the difference in the opening directions of the outlet 147 and the outlet 146 enables gas-liquid separation within the containment case 140. As a result, the outflow of liquid to the downstream side of the containment case 140 is suppressed in the direction of airflow within the circulating air passage 131. Therefore, it is possible to prevent the object to be dried in the processing chamber 112 from becoming wet again due to the liquid seeping out of the adsorbent 139.

[0079] While the airflow generation unit 152 is circulating the air, the heating unit 153 is stopped, so the air temperature gradually decreases. However, as long as the air temperature remains within the release temperature range of the adsorbent 139, the release of water from the adsorbent 139 can continue. For this reason, the circulation control unit 151 continues to operate the airflow generation unit 152 until the temperature detected by the temperature detection unit 155 falls below a predetermined threshold temperature set to be above the lower limit of the release temperature range of the adsorbent 139 (Step S230: No). Note that the closer the threshold temperature is to the lower limit of the release temperature range, the more water will be released from the adsorbent 139, but the more power the airflow generation unit 152 will consume. For this reason, the threshold temperature can be set considering the amount of water released from the adsorbent 139 and the power consumption of the airflow generation unit 152.

[0080] When the temperature detected by the temperature detection unit 155 falls below the threshold temperature (step S230: Yes), the warm air control unit 154 stops the airflow generation unit 152 (step S240). Approximately synchronized with the stopping of the airflow generation unit 152, the circulation control unit 151 opens the on-off valve 135 provided in the secondary air passage 132 and closes the on-off valves 136 and 137 provided in the main air passage 133 (step S250). This prevents water liquid generated by condensation in the circulation air passage 131 when the dryer 100 is not in use from coming into contact with the adsorbent 139.

[0081] In the control shown in Figure 9, the adsorption capacity of the adsorbent 139 is restored by utilizing the residual heat of the air after the drying process is completed. Therefore, the dryer 100 can restore the adsorption capacity of the adsorbent 139 without consuming an excessively large amount of electricity.

[0082] The control shown in Figure 9 is applicable to any of the dryers 100 shown in Figures 2, 6 through 8.

[0083] In the control shown in Figure 9, air flows through the containment case 140 until the temperature detected by the temperature detection unit 155 falls below the threshold temperature (step S230: No), and gas-liquid separation occurs within the containment case 140. To enhance this gas-liquid separation effect, the case body 141 may be tilted as shown in Figure 10, such that the connection part with the drain port 144 is the lowest point on the case body 141. In this case, the liquid seeping from the adsorbent 139 flows through the case body 141 towards the drain port 147. As a result, the discharge of liquid from the containment case 140 is promoted.

[0084] To suppress the outflow of moisture through the outlet 146, a gas-liquid separator 159 may be provided inside the outlet port 143 of the containment case 140, as shown in Figure 11, provided that it does not create excessive resistance to the air passing through the outlet 146. This gas-liquid separator 159 may be composed of a fiber bundle or membrane that allows air to pass through while adsorbing moisture contained in the air. In this case, even if the liquid seeping from the adsorbent 139 evaporates due to the heat of the air, the outflow of this evaporated moisture from the containment case 140 through the outlet 146 is suppressed.

[0085] The dryer 100 in the first and second embodiments has a dehumidifying unit 156. However, if the object to be dried can be dried without the dehumidifying unit 156, the dryer 100 does not need to have the dehumidifying unit 156.

[0086] The dryer 100 in the first and second embodiments is configured as a drum-type washing machine. Alternatively, the dryer 100 may be configured as a top-loading washing machine.

[0087] The dryer 100 in the first and second embodiments has not only a function to dry clothes but also a function to wash clothes. Alternatively, the dryer 100 may have only a function to dry clothes and not a function to wash clothes. In this case, the dryer 100 does not need to have a water supply unit 125.

[0088] The dryer 100 in the first and second embodiments dries clothes as the object to be dried. Alternatively, the dryer 100 may be configured to dry dishes. That is, the air circulation paths shown in Figures 2, 6 to 8 and the control shown in Figures 5 and 9 are also applicable to dishwashers that have a drying function. Since dishes are not as susceptible to deterioration from the heat of the air as clothes, when the technology of this disclosure is applied to a dishwasher, the target temperature may be higher than the target temperature set for drying clothes.

[0089] As described above, the dryer 100 according to one aspect of the second embodiment is configured to dry an object to be dried. The dryer 100 is configured to dry an object to be dried. The dryer 100 comprises a processing chamber 112 for drying an object to be dried, a circulating air passage 131 connected to the processing chamber 112 so that air flowing out of the processing chamber 112 returns to the processing chamber 112, an airflow generating unit 152 that generates a circulating flow of air circulating in the processing chamber 112 and the circulating air passage 131, a heating unit 153 that heats the air circulating in the processing chamber 112 and the circulating air passage 131 toward a predetermined target temperature for drying an object to be dried, and an adsorbent 139 disposed in the circulating air passage 131 which has the characteristic of adsorbing moisture in an adsorption temperature range lower than the target temperature and releasing moisture in a release temperature range including the target temperature. The circulating air passage section 131 is configured to define a first path through which air passes over the adsorbent material 139 and a second path through which air does not pass over the adsorbent material 139. The dryer 100 further includes a switching device 134 that switches the air circulation path so that air flows through the first path when the air is at a temperature within the adsorption temperature range, and air flows through the second path when the air is at a temperature within the release temperature range.

[0090] In the above configuration, when the air is heated by the heating unit 153 to a high temperature at or close to the target temperature, this air is introduced into the processing chamber 112, and the moisture from the material to be dried is absorbed by the air. As a result, the drying of the material to be dried is promoted. Even before such a high temperature state is reached, the adsorbent 139 is used to promote the drying of the material to be dried.

[0091] In other words, for a while after heating of the air begins, the temperature of the air may be within the adsorption temperature range, which is lower than the target temperature. When the air, which is at a temperature within the adsorption temperature range, passes through the adsorbent 139, the adsorbent 139 also reaches a temperature within the adsorption temperature range, and the adsorbent 139 can adsorb the moisture contained in this air. In other words, the air is dehumidified by the adsorbent 139. When this dehumidified air is introduced into the processing chamber 112, drying of the object to be dried is promoted. That is, when air at a temperature within the adsorption temperature range is introduced into the processing chamber 112 through the first path where the adsorbent 139 is provided, drying of the object to be dried is promoted.

[0092] When the air is further heated by the heating unit 153, the temperature of the air may reach a temperature within the release temperature range. If such air continues to flow through the first path, the temperature of the adsorbent 139 will also reach a temperature within the release temperature range, and moisture may be released from the adsorbent 139 into the air. When this air flows into the processing chamber 112, the drying of the object to be dried may be hindered by the moisture released from the adsorbent 139.

[0093] To avoid such a situation, the switching device 134 switches the air circulation path so that air flows through the second path when the air is at the temperature within the release temperature range. In this state, the air circulates without passing through the adsorbent 139, so that moisture released from the adsorbent 139 does not hinder the drying of the object to be dried.

[0094] In the above configuration, the switching device 134 may be configured to switch the circulation path from the first path to the second path on the condition that the air has been heated to a predetermined switching temperature set to a value lower than the discharge temperature range.

[0095] In the configuration described above, when the air is heated to the switching temperature, the air circulation path is switched from the first path to the second path. Since this switching temperature is set to a value lower than the release temperature range, air that is within the release temperature range is prevented from passing through the adsorbent 139.

[0096] In the above configuration, the dryer 100 may further include a temperature detection unit 155 for detecting the temperature of the air in the processing chamber 112 or the circulating air passage 131. The switching device 134 may include an opening / closing unit 150 that opens one of the first and second paths while closing the other path, and a circulation control unit 151 that controls the opening / closing unit 150 so that the first path is opened and the second path is closed when the temperature detected by the temperature detection unit 155 is lower than the switching temperature. The circulation control unit 151 may also control the opening / closing unit 150 so that the first path is closed and the second path is opened when the temperature detected by the temperature detection unit 155 is higher than the switching temperature.

[0097] In the above configuration, when the temperature detected by the temperature detection unit 155 rises above the switching temperature, the opening / closing unit 150 changes from a state where the first path is open and the second path is closed to a state where the second path is open and the first path is closed. As a result, the air returns to the processing chamber 112 without passing through the adsorbent 139, thus preventing the drying of the object to be dried in the processing chamber 112 from being hindered by moisture released from the adsorbent 139.

[0098] In the above configuration, the adsorbent 139 may be configured to recover its adsorption capacity for adsorbing moisture by releasing moisture when it reaches a temperature within the release temperature range. The dryer 100 may have a warm air control unit 154 that controls the airflow generation unit 152 and the heating unit 153 so as to stop heating by the heating unit 153 while maintaining the generation of a circulating flow by the airflow generation unit 152 when predetermined termination conditions for ending the drying process for drying the object to be dried are met. The circulation control unit 151 may control the opening / closing unit 150 to open the first path, provided that the termination conditions are met.

[0099] In the above configuration, when predetermined termination conditions for ending the drying process for drying the object to be dried are met, the warm air control unit 154 stops the heating unit 153, while the airflow generation unit 152 maintains the generation of a circulating flow. At this time, since the first path is open, air flows through the first path. This air is at or near the target temperature due to heating by the heating unit 153 before the termination conditions are met. As this air flows through the first path, the adsorbent 139 is heated by the air and can reach a temperature within the release temperature range. At this temperature, the adsorbent 139 releases moisture, and its adsorption capacity is restored. In other words, the adsorption capacity of the adsorbent 139 can be restored by utilizing the residual heat of the air after the termination conditions have been met. Therefore, the dryer 100 does not need to generate additional heat to restore the adsorption capacity of the adsorbent 139 in addition to the heat required to dry the object to be dried, and power saving of the dryer 100 can be achieved.

[0100] In the above configuration, the dryer 100 may further include a dehumidifying unit 156 that dehumidifies the air so as to cool the air flowing through the second path and cause condensation. The heating unit 153 may be arranged in the circulating air passage 131 to heat the air that has been dehumidified by the dehumidifying unit 156.

[0101] In the configuration described above, air in the processing chamber 112 removes moisture from the object to be dried, thereby drying the object. While this air flows through the second path, the moisture contained in this air condenses in the dehumidification unit 156. At this time, the air is cooled by the dehumidification unit 156, but this air is then heated by the heating unit 153, so the saturated water vapor content of this air increases. As air with a high saturated water vapor content flows into the processing chamber 112, the drying of the object to be dried in the processing chamber 112 is accelerated. Since the humidity of the air is reduced by the dehumidification unit 156, the object to be dried can be dried in a short time.

[0102] In the above configuration, the dryer 100 may further include a dehumidifying unit 156 that dehumidifies the air so as to cool the air flowing through the first path and cause condensation. The heating unit 153 may be arranged in the circulating air passage 131 to heat the air that has been dehumidified by the dehumidifying unit 156.

[0103] In the above configuration, air in the processing chamber 112 removes moisture from the object to be dried, thereby drying the object. While this air flows through the first path, the moisture contained in this air is adsorbed by the adsorbent 139, but some moisture may not be adsorbed by the adsorbent 139. To reduce such moisture, a dehumidifier 156 is provided in the above configuration. If the dehumidifier 156 is located upstream of the adsorbent 139 in the direction of airflow, moisture in the air condenses in the dehumidifier 156 before the air flows to the adsorbent 139. In this case, the amount of moisture in the air passing through the adsorbent 139 is reduced, thus reducing the amount of moisture that cannot be adsorbed by the adsorbent 139. Conversely, if the dehumidifier 156 is located downstream of the adsorbent 139 in the direction of airflow, moisture that was not adsorbed by the adsorbent 139 may condense in the dehumidifier 156. In this way, since the air from which moisture has been removed by the adsorbent 139 and the dehumidifier 156 is heated by the heating unit 153, high-temperature and low-humidity air can flow into the processing chamber 112. Since the humidity of the air is reduced not only by the adsorbent 139 but also by the dehumidifier 156, the object to be dried can be dried in a short time.

[0104] In the above configuration, the adsorbent 139 may be configured such that, at temperatures within the release temperature range, water, which is moisture in a liquid phase, seeps out from the adsorbent 139.

[0105] If moisture is released from the adsorbent 139 in a gaseous state, after the termination condition is met, the moisture may return to the treatment chamber 112 on the air circulating through the circulating air passage 131 and the treatment chamber 112. To suppress such moisture, in the above configuration, the adsorbent 139 is configured so that, at temperatures within the release temperature range, water, which is moisture in a liquid state, seeps out from the adsorbent 139.

[0106] In the above configuration, the dryer 100 may further include a storage case 140 configured to house the adsorbent 139. The storage case 140 may have an inlet 145 through which air flows in, an outlet 146 through which the air that has passed through the adsorbent 139 flows out, and a downward-facing outlet 147 that allows the liquid seeping out from the adsorbent 139 to flow down.

[0107] In the configuration described above, air enters the containment case 140 through the inlet 145 and exits the containment case 140 through the outlet 146. During this time, when the adsorbent 139 reaches the release temperature range due to the heat of the air, water seeps out of the adsorbent 139, but this water flows down through the outlet 147. As a result, the return of water to the treatment chamber 112 along with the air exiting from the outlet 146 of the containment case 140 is suppressed.

[0108] In the above configuration, the outlet 146 may be open upward.

[0109] In the above configuration, since the outlet 146 opens upward, heated air is easily discharged from the containment case 140 through the outlet 146. On the other hand, since liquid water tends to flow downward due to gravity, separation of liquid water and air in the containment case 140 is promoted.

[0110] In the above configuration, the dryer 100 may further include a gas-liquid separation unit 159 that allows the passage of air flowing out from the outlet 146, while restricting the passage of moisture contained in this air.

[0111] In the configuration described above, the flow of moisture contained in the air discharged from the outlet 146 into the processing chamber 112 is restricted by the gas-liquid separation unit 159.

[0112] In the above configuration, the warm air control unit 154 may be configured to stop the airflow generation unit 152 on the condition that the temperature detection unit 155 detects that the air temperature has fallen below a predetermined threshold temperature equal to or greater than the lower limit of the discharge temperature range after the termination condition has been met.

[0113] In the above configuration, when the heating unit 153 is stopped, the air temperature gradually decreases. When the air temperature falls below the lower limit of the release temperature range, the temperature of the adsorbent 139 also falls below the lower limit of the release temperature range, and moisture release from the adsorbent 139 ceases. In this state, the generation of circulating flow by the airflow generation unit 152 does not contribute to the recovery of the adsorption capacity of the adsorbent 139. For this reason, the warm air control unit 154 stops the airflow generation unit 152 when the air temperature falls below a threshold temperature set to be above the lower limit of the release temperature range. If the threshold temperature is set to a value greater than the lower limit of the release temperature range, the airflow generation unit 152 will stop earlier, and power consumption in the airflow generation unit 152 will be suppressed.

[0114] In the above configuration, the warm air control unit 154 may be configured to stop the airflow generation unit 152 on the condition that the temperature detection unit 155 detects that the air temperature has fallen below a predetermined threshold temperature equal to or greater than the lower limit of the discharge temperature range after the termination condition has been met. The opening / closing unit 150 may be configured to open and close the first path on the upstream and downstream sides of the adsorbent 139 in the direction of airflow. The circulation control unit 151 may control the opening / closing unit 150 so that the opening / closing unit 150 closes the first path on the upstream and downstream sides of the adsorbent 139 in the direction of airflow after the termination condition has been met and the temperature detection unit 155 detects that the air temperature has fallen below a threshold temperature.

[0115] It is assumed that condensation will occur in the circulating air passage section 131 when the dryer 100 is not in use. When the water produced by this condensation comes into contact with the adsorbent material 139, the adsorbent material 139 will adsorb this water, which may reduce the adsorption capacity of the adsorbent material 139. To suppress such a reduction in adsorption capacity, in the above configuration, after the airflow generation section 152 stops, the opening / closing section 150 closes the first path on both the upstream and downstream sides of the adsorbent material 139 in the direction of airflow. This prevents water produced by condensation when the dryer 100 is not in use from flowing towards the adsorbent material 139 from both the upstream and downstream sides. As a result, it is possible to prevent the adsorbent material 139 from adsorbing moisture when the dryer 100 is not in use.

[0116] As described above, the first and second embodiments have been presented as examples of the technology disclosed in this application. However, the technology in this disclosure is not limited to these embodiments and can be applied to embodiments that have been modified, replaced, added, or omitted. Furthermore, it is possible to create new embodiments by combining the components described in the first and second embodiments above.

[0117] (Effects, etc.) The dryer 100 according to the above embodiment has the following features and provides the following effects.

[0118] (Technology 1) A dryer according to one aspect of the above-described embodiment is configured to dry an object to be dried. The dryer is configured to dry an object to be dried. The dryer comprises a processing chamber for drying the object to be dried, a circulating air passage connected to the processing chamber so that air flowing out of the processing chamber returns to the processing chamber, an airflow generation unit that generates a circulating flow of air circulating in the processing chamber and the circulating air passage, a heating unit that heats the air circulating in the processing chamber and the circulating air passage toward a predetermined target temperature for drying the object to be dried, and an adsorbent disposed in the circulating air passage, which has the characteristic of adsorbing moisture in an adsorption temperature range lower than the target temperature, while releasing moisture in a release temperature range including the target temperature. The circulating air passage is configured to define a first path through which air passes over the adsorbent and a second path through which air does not pass over the adsorbent. The dryer further comprises a switching device that switches the air circulation path so that air flows through the first path when the air is at a temperature within the adsorption temperature range, and air flows through the second path when the air is at a temperature within the release temperature range.

[0119] In the above configuration, when the air is heated by the heating unit to a high temperature, or close to the target temperature, this air is introduced into the processing chamber, and the moisture in the material to be dried is absorbed by the air. As a result, the drying of the material is promoted. Even before such a high temperature state is reached, an adsorbent is used to promote the drying of the material.

[0120] In other words, for a while after heating of the air begins, the temperature of the air may be within the adsorption temperature range, which is lower than the target temperature. When air that is at the adsorption temperature range passes through the adsorbent, the adsorbent also reaches the adsorption temperature range, and the adsorbent can adsorb the moisture contained in this air. That is, the air is dehumidified by the adsorbent. When this dehumidified air is introduced into the processing chamber, drying of the object to be dried is promoted. In other words, when air that is at the adsorption temperature range is introduced into the processing chamber through the first path where the adsorbent is installed, drying of the object to be dried is promoted.

[0121] If the air is further heated by the heating element, its temperature can reach a temperature within the release temperature range. If such air continues to flow through the first path, the temperature of the adsorbent will also reach a temperature within the release temperature range, and moisture may be released from the adsorbent into the air. When this air flows into the processing chamber, the drying of the object to be dried may be hindered by the moisture released from the adsorbent.

[0122] To avoid such a situation, the switching device switches the air circulation path so that air flows through the second path when the air is at the release temperature range. In this state, the air circulates without passing through the adsorbent, so moisture released from the adsorbent does not hinder the drying of the object being dried.

[0123] (Technology 2) In the configuration described in Technical 1, the switching device may be configured to switch the circulation path from the first path to the second path on the condition that the air has been heated to a predetermined switching temperature set to a value lower than the discharge temperature range.

[0124] In the configuration described above, when the air is heated to the switching temperature, the air circulation path is switched from the first path to the second path. This switching temperature is set to a value lower than the release temperature range, so that air that is within the release temperature range does not pass through the adsorbent.

[0125] (Technology 3) In the configuration described in Technical 2, the dryer may further include a temperature detection unit for detecting the temperature of the air in the processing chamber or the circulating air passage. The switching device may include an opening / closing unit for opening one of the first and second paths while closing the other path, and a circulation control unit that controls the opening / closing unit so that the first path is opened and the second path is closed when the temperature detected by the temperature detection unit is lower than the switching temperature. The circulation control unit may control the opening / closing unit so that the first path is closed and the second path is opened when the temperature detected by the temperature detection unit is higher than the switching temperature.

[0126] In the configuration described above, when the temperature detected by the temperature detection unit rises above the switching temperature, the opening / closing unit changes from a state where the first path is open and the second path is closed to a state where the second path is open and the first path is closed. As a result, the air returns to the processing chamber without passing through the adsorbent, thus preventing moisture released from the adsorbent from hindering the drying of the object to be dried in the processing chamber.

[0127] (Technology 4) In the configuration described in Technical 3, the adsorbent may be configured to recover its adsorption capacity for adsorbing moisture by releasing moisture when it reaches a temperature within the release temperature range. The dryer may have a warm air control unit that controls the airflow generation unit and the heating unit so as to stop heating by the heating unit while maintaining the generation of a circulating flow by the airflow generation unit when predetermined termination conditions for ending the drying process for drying the object to be dried are met. The circulation control unit may control the opening and closing unit to open the first path, provided that the termination conditions are met.

[0128] In the above configuration, when predetermined termination conditions for ending the drying process for drying the object to be dried are met, the warm air control unit stops the heating unit, while the airflow generation unit maintains the generation of a circulating flow. At this time, since the first path is open, air flows through the first path. This air is at or near the target temperature due to heating by the heating unit before the termination conditions are met. As this air flows through the first path, the adsorbent is heated by the air and can reach a temperature within the release temperature range. At this temperature, the adsorbent releases moisture, and its adsorption capacity is restored. In other words, the adsorption capacity of the adsorbent can be restored by utilizing the residual heat of the air after the termination conditions have been met. Therefore, the dryer does not need to generate additional heat to restore the adsorption capacity of the adsorbent in addition to the heat required to dry the object to be dried, and power saving of the dryer can be achieved.

[0129] (Technology 5) In the configuration described in any of Technical 1 to 4, the dryer may further include a dehumidifying unit that dehumidifies the air so as to cool the air flowing through the second path and cause condensation. The heating unit may be arranged in the circulating air passage to heat the air dehumidified by the dehumidifying unit.

[0130] In the configuration described above, air dries the object to be dried in the processing chamber by removing moisture from it. While this air flows through the second path, the moisture contained in this air condenses in the dehumidification section. At this time, the air is cooled by the dehumidification section, but this air is then heated by the heating section, increasing the amount of saturated water vapor in this air. As air with a high saturated water vapor content flows into the processing chamber, the drying of the object to be dried inside the processing chamber is accelerated. Because the humidity of the air is reduced by the dehumidification section, the object to be dried can be dried in a short time.

[0131] (Technology 6) In the configuration described in any of Technical 1 to 4, the dryer may further include a dehumidifying unit that dehumidifies the air so as to cool the air flowing through the first path and cause condensation. The heating unit may be arranged in the circulating air passage to heat the air dehumidified by the dehumidifying unit.

[0132] In the configuration described above, air in the processing chamber removes moisture from the object to be dried, thereby drying the object. While this air flows through the first path, the moisture contained in this air is adsorbed by the adsorbent, but some moisture may not be adsorbed by the adsorbent. To reduce such moisture, a dehumidifier is provided in the configuration described above. If the dehumidifier is located upstream of the adsorbent in the direction of airflow, moisture in the air condenses in the dehumidifier before the air flows to the adsorbent. In this case, the amount of moisture in the air passing through the adsorbent is reduced, thus reducing the amount of moisture that cannot be adsorbed by the adsorbent. Conversely, if the dehumidifier is located downstream of the adsorbent in the direction of airflow, moisture that was not adsorbed by the adsorbent may condense in the dehumidifier. In this way, the air from which moisture has been removed by the adsorbent and the dehumidifier is heated by the heating unit, so high-temperature and low-humidity air can flow into the processing chamber. Since the humidity of the air is reduced not only by the adsorbent but also by the dehumidifier, the object to be dried can be dried in a short time.

[0133] (Technology 7) In the configuration described in Technical 4, the adsorbent may be configured such that, at temperatures within the release temperature range, water, which is in a liquid phase, seeps out from the adsorbent.

[0134] If moisture is released from the adsorbent in a gaseous state, it may return to the treatment chamber on the air circulating through the circulating air passage and treatment chamber after the termination conditions are met. To suppress such moisture, in the above configuration, the adsorbent is configured so that at temperatures within the release temperature range, liquid water seeps out of the adsorbent.

[0135] (Technology 8) In the configuration described in Technical 7, the dryer may further include a containment case configured to house an adsorbent. The containment case may have an inlet for air to flow in, an outlet for air that has passed through the adsorbent to flow out, and a downward-opening outlet to allow liquid seeping from the adsorbent to flow down.

[0136] In the configuration described above, air enters the containment case through the inlet and exits the containment case through the outlet. During this time, when the adsorbent reaches the release temperature range due to the heat of the air, water seeps out of the adsorbent, but this water flows down through the outlet. Therefore, the return of the water to the processing chamber along with the air exiting from the outlet of the containment case is suppressed.

[0137] (Technology 9) In the configuration described in Technical 8, the outlet may be open upwards.

[0138] In the configuration described above, since the outlet opens upward, heated air is easily discharged from the containment case through the outlet. On the other hand, liquid tends to flow downward due to gravity, thus promoting the separation of liquid and air within the containment case.

[0139] (Technology 10) In the configuration described in Technical 8 or 9, the dryer may further include a gas-liquid separation unit that allows the passage of air flowing out from the outlet while restricting the passage of moisture contained in this air.

[0140] In the configuration described above, the flow of moisture contained in the air discharged from the outlet into the processing chamber is restricted by the gas-liquid separation unit.

[0141] (Technology 11) In the configuration described in Technical 4, the warm air control unit may be configured to stop the airflow generation unit on the condition that the temperature detection unit detects that the air temperature has fallen below a predetermined threshold temperature equal to or greater than the lower limit of the discharge temperature range after the termination conditions have been met.

[0142] In the configuration described above, when the heating unit is stopped, the air temperature gradually decreases. When the air temperature falls below the lower limit of the release temperature range, the temperature of the adsorbent also falls below the lower limit of the release temperature range, and moisture release from the adsorbent ceases. In this state, the generation of circulating flow by the airflow generation unit does not contribute to the recovery of the adsorption capacity of the adsorbent. Therefore, the warm air control unit stops the airflow generation unit when the air temperature falls below a threshold temperature set to be above the lower limit of the release temperature range. If the threshold temperature is set to a value greater than the lower limit of the release temperature range, the airflow generation unit will stop earlier, and power consumption in the airflow generation unit will be suppressed.

[0143] (Technology 12) In the configuration described in Technical 4, the warm air control unit may be configured to stop the airflow generation unit on the condition that the temperature detection unit detects that the air temperature has fallen below a predetermined threshold temperature equal to or greater than the lower limit of the discharge temperature range after the termination conditions have been met. The opening / closing unit may be configured to open and close the first path on the upstream and downstream sides of the adsorbent in the direction of airflow. The circulation control unit may control the opening / closing unit so that it closes the first path on the upstream and downstream sides of the adsorbent in the direction of airflow after the termination conditions have been met and the temperature detection unit detects that the air temperature has fallen below a threshold temperature.

[0144] It is anticipated that condensation may occur in the circulating air passage when the dryer is not in use. If the water produced by this condensation comes into contact with the adsorbent, the adsorbent will adsorb this water, which may reduce the adsorption capacity of the adsorbent. To suppress this reduction in adsorption capacity, in the above configuration, after the airflow generation unit stops, the opening and closing unit closes the first path on both the upstream and downstream sides of the adsorbent in the direction of airflow. This prevents water produced by condensation when the dryer is not in use from flowing towards the adsorbent from both the upstream and downstream sides. As a result, it is possible to prevent the adsorbent from adsorbing moisture when the dryer is not in use.

[0145] (Technology 13) In the configuration described in Technical 1, the adsorbent may be configured to recover its adsorption capacity for adsorbing moisture by releasing moisture when it reaches the temperature in the release temperature range. The circulating air passage may be configured to allow the adsorbent to reach the temperature in the release temperature range due to heat transfer from the air flowing through the second path to the adsorbent in the first path.

[0146] In the configuration described above, the heating unit heats the air toward the target temperature. When the air reaches the target temperature or a temperature close to it, the saturated water vapor content of the air increases, promoting the drying of the material to be dried in the processing chamber. At this time, the air flows through the second path, and the heat from this air is transferred to the adsorbent in the first path. As a result of this heat transfer, the adsorbent can reach a temperature within the release temperature range. Under these temperature conditions, moisture is released from the adsorbent, and the adsorption capacity of the adsorbent is restored. Therefore, while the material to be dried is being dried with air at or close to the target temperature, moisture can be released from the adsorbent, restoring its adsorption capacity. For this reason, the dryer does not need to generate additional heat to restore the adsorption capacity of the adsorbent in addition to the heat required to dry the material, thus enabling energy savings for the dryer.

[0147] Since the embodiments described above are for illustrative purposes only, various modifications, substitutions, additions, omissions, etc., can be made within the claims or their equivalents. [Industrial applicability]

[0148] The dryer of the above-described embodiment is suitable for drying items such as clothing, bedding, and tableware after washing. [Explanation of Symbols]

[0149] 100... Dryer 112··········Processing Room 131...Circulating air duct 134···········Switching device 139···········Adsorbent 140··········Storage case 145····························Inlet 146... Outlet 147... 148···········Warm air section 149···········Temperature detection unit 150···········Opening / Closing Section 151···········Circulation Control 152···········Airflow generation section 153... Heating section 154···········Warm-up control unit 155···········Temperature detection unit 156...Dehumidification section 159···········Gas-liquid separation section

Claims

1. A dryer for drying objects, A heating unit that heats the air to a predetermined target temperature for drying the object to be dried, A processing room for drying the material to be dried, A circulating air passage connected to the processing chamber is provided so that the air that flows out of the processing chamber returns to the processing chamber. An airflow generation unit that generates a circulating flow of air that circulates through the processing chamber and the circulating air passage, The adsorbent has the characteristic of adsorbing moisture in an adsorption temperature range lower than the target temperature, while releasing moisture in a release temperature range that includes the target temperature, and is disposed within the circulating air passage. The aforementioned circulating air passage is configured to define a first path through which air passes over the adsorbent and a second path through which air does not pass over the adsorbent. The dryer further includes a switching device for switching the air circulation path such that air flows through the first path when the air is at a temperature within the adsorption temperature range, and air flows through the second path when the air is at a temperature within the release temperature range.

2. The dryer according to claim 1, wherein the switching device is configured to switch the circulation path from the first path to the second path on the condition that the air has been heated to a predetermined switching temperature set to a value lower than the discharge temperature range.

3. The system further includes a temperature detection unit for detecting the temperature of the air in the processing chamber or the circulating air passage, The aforementioned switching device is An opening / closing unit that opens one of the first and second paths while closing the other path, The system includes a circulation control unit that controls the opening / closing unit so that the first path is opened and the second path is closed when the temperature detected by the temperature detection unit is lower than the switching temperature. The dryer according to claim 2, wherein the circulation control unit controls the opening / closing unit so that the first path is closed and the second path is opened when the temperature detected by the temperature detection unit is higher than the switching temperature.

4. The adsorbent is configured to recover its adsorption capacity for adsorbing moisture by releasing moisture. The dryer has a warm air control unit that controls the airflow generation unit and the heating unit so as to stop heating by the heating unit while maintaining the generation of a circulating flow by the airflow generation unit when predetermined termination conditions for ending the drying process for drying the object to be dried are met. The dryer according to claim 3, wherein the circulation control unit controls the opening / closing unit to open the first path on the condition that the termination condition is met.

5. The system further includes a dehumidifying unit that dehumidifies the air so as to cool the air flowing through the second path and cause condensation, The dryer according to claim 1, wherein the heating unit is arranged in the circulating air passage to heat the air dehumidified by the dehumidifying unit.

6. The system further includes a dehumidifying unit that dehumidifies the air so as to cool the air flowing through the first path and cause condensation, The dryer according to claim 1, wherein the heating unit is arranged in the circulating air passage to heat the air dehumidified by the dehumidifying unit.

7. The dryer according to claim 4, wherein the adsorbent is configured such that, at the temperature in the release temperature range, water, which is moisture in a liquid phase, seeps out from the adsorbent.

8. The collection case further comprises a housing case configured to accommodate the aforementioned adsorbent material, The dryer according to claim 7, wherein the containment case is formed with an inlet for air to flow in, an outlet for air that has passed through the adsorbent to flow out, and a downward-opening outlet to allow water seeping from the adsorbent to flow down.

9. The dryer according to claim 8, wherein the outlet is open upward.

10. The dryer according to claim 8, further comprising a gas-liquid separation unit that allows the passage of air flowing out from the outlet while restricting the passage of moisture contained in this air.

11. The dryer according to claim 4, wherein the warm air control unit is configured to stop the airflow generation unit on the condition that the temperature detection unit detects that the air temperature has fallen below a predetermined threshold temperature equal to or greater than the lower limit of the discharge temperature range after the termination condition has been met.

12. The warm air control unit is configured to stop the airflow generation unit after the termination condition has been met and the temperature detection unit has detected that the air temperature has fallen below a predetermined threshold temperature equal to or greater than the lower limit of the discharge temperature range. The opening and closing section is configured to open and close the first path on the upstream and downstream sides of the adsorbent in the direction of airflow. The dryer according to claim 4, wherein the circulation control unit controls the opening and closing unit so that the opening and closing unit closes the first path on the upstream and downstream sides of the adsorbent in the direction of airflow, provided that the temperature detection unit detects that the air temperature has fallen below the threshold temperature after the termination condition has been met.

13. The adsorbent is configured to recover its adsorption capacity for adsorbing moisture by releasing moisture. The dryer according to claim 1, wherein the circulating air passage is configured to allow the adsorbent to reach the temperature of the discharge temperature range due to heat transfer from the air flowing through the second path to the adsorbent in the first path.

Images