Washing machine

Abstract

In a configuration where power is supplied to the fan and the control unit that controls various devices built into the washing machine by the same switching power supply, the washing machine can continue to operate even if a short-circuit failure occurs in the fan. [Solution] The dishwasher 1 includes an operation control unit 51 that controls the operation of the washing pump 23 and the fan 65, a switching power supply 70 that stops supplying power to the operation control unit 51 and the fan 65 when an overcurrent is detected, and a storage unit 53 that stores fault information when an overcurrent is detected when the switching power supply 70 supplies power to the fan 65 during the steam recovery process. The switching power supply 70 has an automatic recovery function that restores power supply to the control unit 50 after power supply has been stopped due to overcurrent detection. If fault information is stored in the storage unit when power supply is restored, the control unit 50 controls the switching power supply 70 to prohibit power supply to the fan 65.

Description

Technical Field

[0001] The present invention relates to a cleaning machine for cleaning objects to be cleaned such as tableware.

Background Art

[0002] For example, a cleaning machine is known that includes a main body having a cleaning chamber and a heat exchange unit that condenses water vapor discharged from the cleaning chamber and discharges air with a reduced water vapor content. The heat exchange unit has a housing, a heat exchanger provided inside the housing, and a fan motor that discharges air with a reduced water vapor content by the heat exchanger to the outside of the housing. In the cleaning machine described in Patent Document 1, the feed water can be heated by the conventionally exhausted water vapor (steam), and the air with a reduced water vapor content can be discharged outside the machine.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above conventional cleaning machine, the fan motor that drives the fan is supplied with power by a switching power supply, and the control unit that controls various devices (for example, a cleaning pump, a rinsing pump, various sensors, etc.) built in the cleaning machine is supplied with power by a transformer power supply. However, when a liquid crystal display (LCD) is used as a display device or a Wi-Fi terminal or the like is mounted, it is necessary to increase the rated current for the control unit that controls these. When the rated current increases, the size of the transformer and the size of the heat sink increase, making it difficult to mount them on the housing of the cleaning machine main body.

[0005] Therefore, it is conceivable that the control unit, which controls the various devices built into the washing machine, should also be powered by the same switching power supply that controls the power supply to the fan. However, if the fan and the control unit are powered by the same switching power supply, and power is supplied to the fan that short-circuits during the steam recovery process, the output voltage of the switching power supply will drop due to overcurrent protection, and power will not be supplied to the control unit and, consequently, to the various devices. Even if power is restored to the switching power supply after the overcurrent is cleared, the overcurrent protection function will activate again when power is supplied to the fan, and power will not be supplied to the various devices. As a result, the washing machine will be unable to perform washing operations.

[0006] Therefore, the object of the present invention is to provide a washing machine that can perform washing operations even if a short-circuit failure occurs in the fan, in a configuration in which power is supplied to the control unit that controls the fan and various devices built into the washing machine by the same switching power supply. [Means for solving the problem]

[0007] (1) A washing machine according to one aspect of the present invention comprises a washing machine body for washing objects housed in a washing chamber during a washing process, and a steam recovery unit for recovering steam generated in the washing chamber by heat exchange during a steam recovery process, wherein the steam recovery unit has a fan that takes in steam from the washing chamber and discharges dry air with a reduced amount of steam content to the outside of the washing chamber, a control unit that controls the operation of at least a washing pump and a fan that supply washing water to the washing chamber among the various devices provided in the washing machine, a switching power supply that supplies power to the control unit and the fan and stops the supply of power to the control unit and the fan when an overcurrent is detected, and a storage unit that stores fault information indicating that there is a malfunction in the fan when an overcurrent is detected when supplying power to the fan during the steam recovery process, wherein the switching power supply has an automatic recovery function that restores the power supply to the control unit after the power supply has been stopped due to overcurrent detection, and the control unit controls the switching power supply to prohibit the supply of power to the fan if fault information is stored in the storage unit when the power supply is restored.

[0008] In this configuration of the washing machine, if an overcurrent occurs when power is supplied to the fan during the steam recovery process, information indicating a fan malfunction (fault information) is stored, and the power supply from the switching power supply is stopped. Then, in this configuration of the washing machine, if the aforementioned fault information is stored, when the power supply from the switching power supply is automatically restored, power supply from the switching power supply to the control unit is started only, and power supply to the fan is prohibited. As a result, even if power supply from the switching power supply is started, an overcurrent caused by the fan will not occur again, and the supply of operating power to the control unit will not be stopped again. In this configuration, where power to the fan and the control unit that controls various devices built into the washing machine is supplied by the same switching power supply, the washing machine can continue to operate even if a short-circuit failure occurs in the fan.

[0009] (2) In the washing machine described in (1) above, the steam recovery process may be restarted with the power supply to the fan disabled. With this configuration, the washing operation can be terminated while maintaining the washing operation time when there is no fan malfunction. [Effects of the Invention]

[0010] According to the present invention, in a configuration in which power is supplied to the operation control unit that controls the fan and various devices built into the washing machine by the same switching power supply, the washing machine can be operated even if a short-circuit failure occurs in the fan. [Brief explanation of the drawing]

[0011] [Figure 1] Figure 1 is a perspective view of a dishwasher according to one embodiment. [Figure 2] Figure 2 is a cross-sectional view showing a schematic configuration of a dishwasher according to one embodiment. [Figure 3] Figure 3 is a block diagram showing the functional configuration of a dishwasher. [Figure 4] Figure 4(A) is a timing chart for the steam recovery process under normal conditions. Figure 4(B) is a timing chart for the steam recovery process when an overcurrent occurs. [Figure 5] Figure 5 is a diagram showing the transition of fan states stored in the memory unit of one embodiment or modified example 1. [Modes for carrying out the invention]

[0012] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. In the description of the drawings, the same or equivalent elements are denoted by the same reference numerals, and redundant descriptions are omitted. The dimensional ratios in the drawings do not necessarily match those in the description. In the following description, for the sake of clarity, the directions (up and down direction, front and back direction, left and right direction) as defined in Figure 1 will be defined.

[0013] As shown in Figures 1 and 2, the dishwasher (washer) 1 has a washing machine body 2 covered with stainless steel panels. The washing machine body 2 is divided into an upper part 2A in which the washing chamber 3 is formed and a lower part 2B in which the machine chamber 4 is formed. At the corner on the rear side of the washing machine body 2, support columns 6 are arranged to extend vertically across the upper part 2A and the lower part 2B, and a rear panel 5 is arranged between the support columns 6, 6.

[0014] The upper part 2A of the washing machine body 2 is provided with a box-shaped door 7 for opening and closing the washing chamber 3. This door 7 is guided to move up and down by a pair of stainless steel support columns 6, 6 and is also moved up and down by a handle 8A that extends horizontally in front of it. The ends of a pair of left and right rotating arms 8B, 8B are fixed to both ends of this handle 8A, and the rotating arms 8B, 8B are positioned diagonally along the side surface 7A of the door 7. One end of a link section 8C, which is positioned along the side surface 7A of the door 7, is rotatably connected to the rotating arms 8B, 8B, and the other end of the link section 8C is connected to the door 7 via an axle pin 8D, so that the door 7 can move up and down in response to the rotational movement of the handle 8A. Legs 9 are attached to the four corners of the bottom surface of the washing machine body 2.

[0015] A rack rail 10 is detachably positioned inside the washing chamber 3, and a grid-like dish rack, on which dishes such as plates and bowls (items to be washed) are arranged after eating and drinking, is placed on this rack rail 10. An upper nozzle 11 is positioned at the top of the washing chamber 3. A lower nozzle 12 is positioned at the bottom of the washing chamber 3.

[0016] The upper nozzle 11 is rotatably provided on an upper support 13 provided above the cleaning chamber 3. The upper nozzle 11 has a main body portion 11A that extends from a base end portion, which is the center of rotation of the rotation axis of the upper nozzle 11, along the radial direction to a tip end portion. In the main body portion 11A, there are provided an upper cleaning injection hole 11B for injecting the cleaning water stored in the cleaning water tank 15, an upper cleaning flow path (not shown) that extends from the center of rotation to the cleaning injection hole (not shown) and through which the cleaning water flows, an upper rinsing injection hole 11C for injecting the rinsing water stored in the rinsing water tank 25, and an upper rinsing flow path (not shown) that extends from the center of rotation to the rinsing injection hole and through which the rinsing water flows, which are integrally formed.

[0017] The upper nozzle 11 rotates when the flow of the cleaning water generated in the cleaning flow path or the flow of the rinsing water generated in the rinsing flow path is converted into a rotational force. Connected to the upper nozzle 11 via the upper support 13 are a first cleaning water discharge pipe 21A for supplying the cleaning water to the cleaning flow path and a first rinsing water discharge pipe 31A for supplying the rinsing water to the rinsing flow path.

[0018] The lower nozzle 12 is rotatably provided on a lower support 14 provided below the cleaning chamber 3. The lower nozzle 12 has a main body portion 12A that extends from a base end portion, which is the center of rotation of the rotation axis of the lower nozzle 12, along the radial direction to a tip end portion. In the main body portion 12A, there are provided a lower cleaning injection hole 12B for injecting the cleaning water stored in the cleaning water tank 15, a lower cleaning flow path (not shown) that extends from the center of rotation to the cleaning injection hole and through which the cleaning water flows, a lower rinsing injection hole 12C for injecting the rinsing water stored in the rinsing water tank 25, and a lower rinsing flow path (not shown) that extends from the center of rotation to the rinsing injection hole and through which the rinsing water flows, which are integrally formed.

[0019] The lower nozzle 12 rotates when the flow of the cleaning water generated in the cleaning flow path or the flow of the rinsing water generated in the rinsing flow path is converted into a rotational force. Connected to the lower nozzle 12 are a second cleaning water discharge pipe 21B for supplying the cleaning water to the cleaning flow path and a second rinsing water discharge pipe 31B for supplying the rinsing water to the rinsing flow path.

[0020] At the bottom of the cleaning chamber 3, a cleaning water tank 15 is provided so as to protrude into the machine chamber 4. A filter 18 is detachably arranged between the cleaning chamber 3 and the cleaning water tank 15. A cleaning pump 23 is connected to the front surface of the cleaning water tank 15 via a cleaning water suction port. A cleaning water discharge pipe 21 is connected to the discharge port of the cleaning pump 23. The cleaning water discharge pipe 21 branches into a first cleaning water discharge pipe 21A and a second cleaning water discharge pipe 21B. The first cleaning water discharge pipe 21A is connected to the upper cleaning flow path, and the second cleaning water discharge pipe 21B is connected to the lower cleaning flow path.

[0021] The cleaning water tank 15 is provided with a cleaning water detection unit 15A, a cleaning water heater 15B, and a cleaning water temperature sensor 15C. The cleaning water detection unit 15A detects the water level of the cleaning water stored in the cleaning water tank 15. The cleaning water heater 15B heats the cleaning water stored in the cleaning water tank 15 to improve the sterilization ability and cleaning ability. The cleaning water temperature sensor 15C detects the temperature of the cleaning water stored in the cleaning water tank 15.

[0022] The cleaning water tank 15 is provided with an overflow pipe 33 which is a pipe-shaped member extending in the vertical direction and regulates the water level of the cleaning water stored in the cleaning water tank 15 by discharging the water exceeding the specified water level in the cleaning water tank 15 to the outside of the cleaning water tank 15. The overflow pipe 33 is provided in a detachable manner at a discharge hole 15d for discharging the water stored in the cleaning water tank 15. When the overflow pipe 33 is pulled out from the discharge hole 15d, the water stored in the cleaning water tank 15 is discharged through a discharge pipe 35.

[0023] Inside the machine room 4, there is a rinse water tank 25 to which rinse water is supplied from the outside via a water supply pipe (not shown). A rinse pump 27 is connected to the rinse water tank 25 via a rinse water suction pipe 29. A rinse water discharge pipe 31 is connected to the discharge port of the rinse pump 27. The rinse water discharge pipe 31 branches into a first rinse water discharge pipe 31A and a second rinse water discharge pipe 31B, with the first rinse water discharge pipe 31A connected to the upper rinse flow path and the second rinse water discharge pipe 31B connected to the lower rinse flow path. The first rinse water discharge pipe 31A is located inside the first wash water discharge pipe 21A. In other words, the first wash water discharge pipe 21A and the first rinse water discharge pipe 31A form a double-pipe structure.

[0024] The rinse water tank 25 is equipped with a rinse water detection unit 25A, a rinse water heater 25B, and a rinse water temperature sensor 25C. The rinse water detection unit 25A detects the water level of the rinse water stored in the rinse water tank 25. The rinse water heater 25B heats the rinse water stored in the rinse water tank 25 to improve its sterilization and rinsing capabilities. The rinse water temperature sensor 25C detects the temperature of the rinse water stored in the rinse water tank 25.

[0025] The washing machine body 2 forms the washing chamber 3. The dishwasher 1 is equipped with a steam recovery unit 60. The steam recovery unit 60 is a unit that takes in water vapor discharged from the washing chamber 3 of the washing machine body 2, condenses the taken-in water vapor, and discharges air with a reduced water vapor content (hereinafter also referred to as "dry air") outside the machine. Outside the machine means the space outside the washing machine body 2 that forms the washing chamber 3. The steam recovery unit 60 has an exhaust duct 61, a heat exchanger 63, and a fan 65.

[0026] The exhaust duct 61 connects the washing chamber 3 to the outside of the washing machine body 2 and has a first connecting passage 61A extending upward from an opening (not shown) formed in the washing chamber 3, and a second connecting passage 61B extending from the first connecting passage 61A to the outside of the machine in a front-to-back direction intersecting the vertical direction in which the first connecting passage 61A extends. The exhaust duct 61 is made of, for example, stainless steel.

[0027] The heat exchanger 63 is located in the first communication passage 61A. The heat exchanger 63 condenses the steam generated in the washing chamber 3 and converts it into air with a reduced amount of steam. The heat exchanger 63 has fins and flow tubes (neither of which are shown). A water supply pipe (not shown) is connected to one end of the flow tube. The water supply pipe supplies water to the flow tube. Water is supplied to the water supply pipe from a water source such as a water tap (not shown). A drain pipe (not shown) is connected to the other end of the flow tube. The drain pipe discharges the water that has passed through the flow tube. The drain pipe is connected to the rinse water tank 25. That is, the water that has flowed through the flow tube of the heat exchanger 63 is discharged into the rinse water tank 25. The heat exchanger 63 comes into contact with the steam flowing through the first communication passage 61A. The heat exchanger 63 performs heat exchange between the water flowing through the flow tube and the steam.

[0028] Fan 65 is located in the second communication passage 61B. Fan 65 is fixed to the exhaust duct 61 via a bracket (not shown). Fan 65 draws in air and sends it out of the machine. Fan 65 takes in water vapor from the washing chamber 3 into the exhaust duct 61 and discharges dry air from the exhaust duct 61 to the outside of the washing chamber 3. Fan 65 is driven by a DC motor. The fan motor that drives fan 65 is controlled by the control unit 50. Hereafter, when it is simply stated that "fan 65 is controlled", it means that "the fan motor that drives fan 65 is controlled". Fan 65 is supplied with the power necessary for its operation from a switching power supply 70, which will be described later.

[0029] The operation display unit 40 is an operation unit that receives various operations from the user. The operation display unit 40 is equipped with an operation power button 41 that receives switching instructions to switch the operation power ON or OFF, a display unit 43 that displays temperature information of the washing water and rinsing water and other information, various setting buttons 45, a pause button 47 for pausing the operation, and an indicator lamp (not shown) that informs the user of the operating status of the dishwasher 1 and whether there are any abnormalities in the initial hot water supply. The display unit 43 is composed of, for example, a liquid crystal display (LCD). The dishwasher 1 may be equipped with communication equipment such as a Wi-Fi terminal.

[0030] The machine room 4 is further equipped with a control unit 50 and a switching power supply 70. The control unit 50 controls the overall operation of the dishwasher 1. The control unit 50 is built into an electrical box (not shown). The control unit 50 is a computer system or processor implemented on an integrated circuit. The control unit 50 is composed of, for example, a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), etc. As shown in Figure 3, the control unit 50 is formed by the cooperation of hardware such as the CPU, RAM, and ROM and software such as programs to form the operation control unit 51 and the power control unit 57. In Figure 3, solid lines indicate the connection status of communication lines, and dashed lines indicate the connection status of power lines. The control unit 50 further has a storage unit 53. The control unit 50 is supplied with power according to the specifications required for operation (e.g., 12V) from the switching power supply 70, which will be described later.

[0031] The operation control unit 51 controls the operation of at least the washing pump 23 and the fan 65, which supply washing water to the dishwasher 1, among the various devices provided in the dishwasher 1. In this embodiment, the control unit 50 is mainly connected to control the operation of the washing water detection unit 15A, the washing water temperature sensor 15C, the rinse water detection unit 25A, the rinse water temperature sensor 25C, the washing pump 23, the rinse pump 27, the operation display unit 40, and the fan 65. In the following description, "controlling the operation of the fan 65" simply means controlling the fan motor that drives the fan.

[0032] The memory unit 53 stores the state of the fan 65. When an overcurrent is detected when power is supplied to the fan 65 during the steam recovery process, the memory unit 53 stores fault information indicating that the fan 65 is malfunctioning. In this embodiment, the memory unit 53 stores "1" as the state (fault information) of the fan 65 indicating that there is an abnormality (malfunction) in the fan 65, and "0" as the state of the fan 65 indicating that there is no abnormality (it is normal). The memory unit 53 is composed of RAM (Random Access Memory), SSD (Solid State Drive), etc.

[0033] The power control unit 57 controls the switching power supply 70 to provide power to each component of the dishwasher 1 according to predetermined specifications. In this embodiment, the power control unit 57 controls the switching power supply 70 to prohibit power supply to the fan 65 when fault information is stored in the storage unit 53 at the time the switching power supply 70, which will be described in detail later, automatically recovers and power supply to the control unit 30 is restored (restarted). In this embodiment, if "1" is stored in the storage unit 53 as the state of the fan 65 at the time power supply to the control unit 30 is restored, the power control unit 57 controls the switching power supply 70 to prohibit power supply to the fan 65.

[0034] An example of control that prohibits power supply from the switching power supply 70 to the fan 65 includes, for example, controlling a device that turns an electrical circuit on and off, such as a relay switch provided on the power line connecting the switching power supply 70 and the fan 65. In this case, power supply from the switching power supply 70 to the fan 65 can be prohibited by a simple circuit configuration. Alternatively, as an example of control that prohibits power supply from the switching power supply 70 to the fan 65, the power control unit 57 may directly control the switching power supply 70.

[0035] The switching power supply 70 is a power supply that converts voltage from AC (alternating current) to DC (direct current). The switching power supply 70 is a so-called AC-DC converter. More specifically, the switching power supply 70 can convert the voltage of a DC power supply and output a specific voltage. In this embodiment, the switching power supply 70 supplies power to the control unit 50 and the fan 65, and stops supplying power to the control unit 50 and the fan 65 when an overcurrent is detected. The switching power supply 70 has an automatic recovery function that automatically restores power supply to the control unit 50 after the power supply has been stopped due to overcurrent detection.

[0036] If the switching power supply 70 does not have an automatic recovery function, a receiving unit 55 may be provided, which is an interface that receives a command to start power supply to the control unit 50 and the fan 65. The receiving unit 55 is configured in the control unit 50 through the cooperation of hardware such as the CPU, RAM, and ROM, and software such as a program. In this case, the receiving unit 55 receives a command to start power supply by detecting that the user has operated the power button 41 on the operation display unit 40, and transmits the received power supply start command to the switching power supply 70. As a result, when the switching power supply 70 receives a power start command after the power supply has been stopped due to overcurrent detection, it resumes supplying power to the control unit 50.

[0037] Next, the operation of the dishwasher 1 of this embodiment will be explained, mainly with reference to Figures 4(A), 4(B), and 5. The dishwasher 1 performs a washing process, a rinsing process, and a steam recovery process as one operating cycle. As shown in Figure 5, when the user turns on the power button 41 of the operation display unit 40 (step S1), a voltage of 12V is applied to the control unit 50 from the switching power supply 70, as shown in Figure 4(A). This starts the supply of power to the control unit 50, making it possible to operate the dishwasher 1.

[0038] Next, as shown in Figure 5, the power control unit 57 reads the status of the fan 65 from the memory unit 53. The memory unit 53 stores "0" when the status of the fan 65 is normal, and "1" (fault information) when the status of the fan 65 is abnormal. When the power control unit 57 reads "1" as the status of the fan 65 from the memory unit 53, it determines that there is an abnormality in the fan 65 and thereafter prohibits the supply of power from the switching power supply 70 to the fan 65 (step S5).

[0039] When the power control unit 57 reads a value other than "1" (i.e., "0") from the memory unit 53 as the status of the fan 65, it determines that there is no abnormality in the fan 65 (it is normal) and allows power to be supplied to the fan 65 from the switching power supply 70 thereafter (step S3). Next, the operation control unit 51 performs a washing operation (washing process and rinsing process) to wash and rinse the dishes. Specifically, hot water is supplied to the washing water tank 15 by spraying hot water from the rinsing water tank 25 into the washing chamber 3 using the rinsing pump 27. The temperature of the hot water in the rinsing water tank 25 is set to, for example, around 80°C. This performs the initial hot water supply. Then, an amount of detergent corresponding to the initial hot water supply is supplied to the washing water tank 15, and the detergent concentration of the washing water in the washing water tank 15 reaches a predetermined concentration.

[0040] After the initial hot water supply, when the user racks the dishes and closes door 7, the door switch detects that the door has been closed, and an operation start signal is input to the control unit 50. When the operation start signal is input to the control unit 50, the washing of dishes (washing process) begins. The dishes are washed by spraying the washing water in the washing water tank 15 towards the dishes in the washing chamber 3. The temperature of the washing water in the washing water tank 15 is set to, for example, 60°C to 70°C.

[0041] When the washing pump 23 is started, the washing water stored in the washing water tank 15 is pressurized and sent to the upper nozzle 11 and lower nozzle 12 via the washing water discharge pipe 21, etc., and sprayed from the upper nozzle 11 and lower nozzle 12 towards the dishes in the washing chamber 3. At this time, the upper nozzle 11 and lower nozzle 12 continue to rotate due to the reaction force of the spray, so that the washing water is evenly applied to the dishes and the dirt on the dishes is efficiently washed away.

[0042] The washing water sprayed into the washing chamber 3 is collected in the washing water tank 15, with any food residue removed by the filter 18. The washing water collected in the washing water tank 15 is then circulated back into the washing chamber 3 by the washing pump 23. Once the dishes have been washed with the washing water for a predetermined time, the washing pump 23 is stopped. This temporarily halts the operation of the dishwasher 1.

[0043] Next, when the rinsing pump 27 is started, the rinsing water stored in the rinsing water tank 25 is pressurized and sent to the upper nozzle 11 and lower nozzle 12 via the rinsing water discharge pipe 31, etc., and sprayed from the upper nozzle 11 and lower nozzle 12 towards the dishes (rinsing process). The temperature of the rinsing water pressurized and sent from the rinsing water tank 25 is set to, for example, around 80°C. At this time, the upper nozzle 11 and lower nozzle 12 also continue to rotate due to the reaction force of the spray, so that the rinsing water is evenly applied to the dishes and the dishes are rinsed efficiently.

[0044] The rinse water sprayed onto the dishes is collected in the washing water tank 15 via the filter 18 and mixed with the washing water, and used as the washing water in the next washing process. When rinse water is sprayed into the washing chamber 3 and collected in the washing water tank 15, any excess washing water exceeding a certain water level is discharged to the outside via the overflow pipe 33 and the discharge pipe 35. When rinse water is sprayed onto the dishes from the upper nozzle 11 and the lower nozzle 12, steam is generated in the washing chamber 3.

[0045] Once the above-described cleaning operation is complete, the operation control unit 51 starts a steam recovery process to recover the steam generated in the cleaning chamber 3 by heat exchange. Specifically, as shown in Figure 4(A), the operation control unit 51 drives the fan 65 for a predetermined time (for example, 180 seconds) as part of the steam recovery process. At this point, the power control unit 57 changes the state of the fan 65 stored in the memory unit 53 from "0" to "1" and starts the timer, either a little before or simultaneously with the start of the steam recovery process.

[0046] The power control unit 57 monitors whether or not an overcurrent occurs when power is supplied to the fan 65 during the steam recovery process. If the operation control unit 51 does not detect the occurrence of an overcurrent and the timer count has elapsed for a predetermined time (for example, 2 seconds) starting from the start of operation of the fan 65, it changes the state of the fan 65 stored in the memory unit 53 from "1" to "0", as shown in Figure 4(A). When the power control unit 57 reads "0" as the state of the fan 65 from the memory unit 53, it determines that there is no abnormality in the fan 65 (normal) and allows power to be supplied to the fan 65 from the switching power supply 70 thereafter (step S4). The predetermined time (for example, 2 seconds) is set to a time that is appropriately adjusted to allow for distinction from momentary power outages.

[0047] On the other hand, if an overcurrent to the fan 65 is detected within a predetermined time (for example, 2 seconds) from the start of operation of the fan 65, the power supply from the switching power supply 70 to the control unit 50 is stopped, as shown in Figure 4(B). That is, the voltage supplied to the control unit 50 by the switching power supply 70 becomes 0. As a result, the operation control unit 51 is unable to control the fan 65, and the operation of the fan 65 stops. In this case, as described above, the timer count has not elapsed for the predetermined time (for example, 2 seconds) from the start of operation of the fan 65, so as shown in Figure 4(A), the state of the fan 65 stored in the memory unit 53 is not changed from "1" to "0", and as shown in Figure 4(B), the state of the fan 65 remains "1".

[0048] The switching power supply 70 automatically returns to a state where power can be supplied after power supply has been stopped following an overcurrent. When the switching power supply 70 automatically returns to a state where power can be supplied, as shown in Figure 4(B), the application of a 12V voltage to the control unit 50 is resumed. As a result, power is supplied to the control unit 50 again, and the operation of the dishwasher 1 becomes possible again.

[0049] The power control unit 57 reads the status of the fan 65 from the memory unit 53. If an overcurrent to the fan 65 is detected, the memory unit 53 will retain the status of the fan 65 as "1," as shown in Figure 4(B). As a result, when power supply is started, the power control unit 57 reads "1" from the memory unit 53 as the status of the fan 65. The power control unit 57 determines that there is an abnormality in the fan 65 and thereafter prohibits the supply of power from the switching power supply to the fan 65. This prevents another overcurrent from occurring due to the supply of power to the fan 65 (and consequently, prevents the power supply from the switching power supply 70 from stopping).

[0050] Next, the effects of the dishwasher 1 of the above embodiment will be explained. In the dishwasher 1 of the above embodiment, if an overcurrent occurs when power is supplied to the fan 65 during the steam recovery process, "1" is stored as the state of the fan 65, and the power supply from the switching power supply 70 is stopped. Furthermore, in the dishwasher 1 of the above embodiment, if "1" is stored as the state of the fan 65, even if a power supply start command is received, the power supply from the switching power supply 70 to the fan 65 is prohibited, and only the power supply to the operation control unit 51 is started. As a result, even if the power supply from the switching power supply 70 is restarted, an overcurrent caused by the fan 65 will not occur again, and the power supply to the operation control unit 51 will not be stopped. As a result, in a configuration in which power to the fan 65 and the operation control unit 51 that controls various devices built into the dishwasher 1 is supplied by the same switching power supply 70, the washing operation of the dishwasher 1 can be performed (continued) even if a short-circuit failure occurs in the fan 65.

[0051] In the above embodiment, the switching power supply 70 has an automatic recovery function that automatically restores power supply to the control unit 50 after the power supply is stopped due to overcurrent detection. As a result, power supply to the control unit 50 is automatically restored without the user having to operate the power button 41. When power supply is restored, if the memory unit 53 stores "1" (fault information) as the status of the fan 65, the control unit 50 restarts the steam recovery process with power supply from the switching power supply 70 to the fan 65 prohibited.

[0052] According to the washing machine of the above embodiment, even if the power supply is stopped due to the detection of an overcurrent, the power supply is automatically restored. Therefore, as shown in the voltage state of the switching power supply 70 in Figure 4(B), for example, when the power supply is automatically restored (dashed line), the time it takes for the power supply to the control unit 50 to be restored can be shortened compared to when the power supply is started by the user's operation (solid line). In other words, the time during which the power supply by the switching power supply 70 is stopped when an overcurrent occurs can be shortened.

[0053] Furthermore, with the washing machine of the above embodiment, the steam recovery process is not interrupted midway through the operation cycle. This prevents the user from being confused about whether the dishes have been washed or whether they need to run the machine again, which can occur if the steam recovery process is interrupted and the operation cycle stops midway.

[0054] Although one embodiment has been described above, the present invention is not limited to the above embodiment. Various modifications are possible without departing from the spirit of the invention. (Variation 1) In the above embodiment, the memory unit 53 was described as storing "0" as the state of the fan 65 indicating that there is no abnormality (it is normal) and "1" as the state of the fan 65 indicating that there is an abnormality (fault) (fault information), but it is not limited to this. For example, the memory unit 53 may store "0" when the state of the fan 65 is normal, and "1" (fault information) or "2" (fault information) when the state of the fan 65 is abnormal. The operation of the dishwasher 1 with such a configuration will be explained mainly with reference to Figure 5. The details of the washing operation in the washing process and the rinsing operation in the rinsing process are as described in the above embodiment, so here we will explain the operation of the dishwasher 1 after automatic recovery when an overcurrent occurs in the steam recovery process.

[0055] As shown in Figure 5, the switching power supply 70 automatically returns to a state where power can be supplied after the power supply has been stopped following an overcurrent. When the switching power supply 70 automatically returns to a state where power can be supplied, as shown in Figure 4(B), the application of a 12V voltage to the control unit 50 is resumed. As a result, power is supplied to the control unit 50 again, and the operation of the dishwasher 1 becomes possible once more.

[0056] Next, the power control unit 57 reads the status of the fan 65 from the memory unit 53. When the power control unit 57 reads "1" as the status of the fan 65 from the memory unit 53, it changes the status of the fan 65 stored in the memory unit 53 from "1" to "2", determines that there is an abnormality in the fan 65, and thereafter prohibits the supply of power from the switching power supply 70 to the fan 65 (step S5). Also, when the operation control unit 51 reads "1" as the status of the fan 65 from the memory unit 53, it restarts the operation of the dishwasher 1 from the steam recovery process.

[0057] Meanwhile, when the power control unit 57 reads "2" from the memory unit 53 as the status of the fan 65, it determines that there is an abnormality in the fan 65 and prohibits the supply of power from the switching power supply 70 to the fan 65 thereafter (step S5). Also, when the operation control unit 51 reads "2" from the memory unit 53 as the status of the fan 65, instead of restarting the operation of the dishwasher 1 from the steam recovery process, it puts the dishwasher 1 into standby mode, waiting for the user to operate the power button 41. Then, when the operation control unit 51 detects that the user has operated the power button 41, it restarts the operation of the dishwasher 1 from the washing process.

[0058] In the dishwasher 1 configuration according to Modification 1, the system determines whether to restart the dishwasher 1 from the steam recovery process when an overcurrent occurs, or to start the dishwasher 1 from the washing process when the power is turned on, depending on the state of the fan 65 stored in the memory unit 53 at the time of automatic recovery. For example, with this configuration, if a short circuit occurs in the fan 65 during the steam recovery process, the dishwasher 1 can be operated until one operating cycle is completed and the power is turned off.

[0059] (Other variations) In the above embodiments and modifications, an example was given in which the switching power supply 70 automatically recovers and resumes power supply in response to a power supply interruption to the control unit 50 caused by an overcurrent during power supply to the fan 65 in the steam recovery process. However, the power supply to the control unit 50 may be resumed by the user operating the power button 41.

[0060] In the above embodiments and modifications, the timing of when the fan 65 starts operating after the washing and rinsing processes are completed was described as an example. However, the timing is not limited to this, and the fan 65 may start operating from the washing process when water is sprayed from the upper nozzle 11 and the lower nozzle 12, or it may start after the washing process is completed.

[0061] In the above embodiments and modifications, control caused by a short circuit of the fan 65 occurring during course operation or the recovery process was described as an example, but it can also be applied to, for example, a maintenance mode in which the fan 65 is operating.

[0062] In the above embodiments and modifications, examples were given in which the operation control unit 51, the reception unit 55, and the power control unit 57 as functional blocks are configured by a single control unit 50. However, each functional block may be implemented using a single device that is physically or logically coupled, or it may be implemented using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wired or wireless connections). A functional block may also be implemented by combining the above single device or the above multiple devices with software.

[0063] Furthermore, the present invention may be appropriately combined with the above embodiments and modifications. [Explanation of symbols]

[0064] 1...Dishwasher (washer), 3...Washing chamber, 4...Machine room, 23...Washing pump, 27...Rinse pump, 40...Operation display unit, 41...Power button, 43...Display unit, 50...Control unit, 51...Operation control unit, 53...Storage unit, 55...Reception unit, 57...Power control unit, 60...Steam recovery unit, 65...Fan, 70...Switching power supply.

Claims

1. A washing machine comprising a washing machine body for washing objects to be washed contained in a washing chamber during the washing process, and a steam recovery unit for recovering steam generated in the washing chamber by heat exchange during the steam recovery process, The steam recovery unit has a fan that takes in the water vapor from the washing chamber and discharges dry air with a reduced water vapor content to the outside of the washing chamber, Among the various devices provided in the washing machine, at least a washing pump that supplies washing water to the washing chamber and a control unit that controls the operation of the fan, A switching power supply that supplies power to the control unit and the fan, and stops supplying power to the control unit and the fan when an overcurrent is detected, The device includes a storage unit that stores fault information indicating a malfunction in the fan when an overcurrent is detected during the steam recovery process when power is supplied to the fan. The switching power supply has an automatic recovery function that restores power supply to the control unit after the power supply is stopped due to the detection of an overcurrent. A washing machine in which the control unit controls the switching power supply to the fan to prohibit power supply if the fault information is stored in the memory unit when power supply is restored.

2. The washing machine according to claim 1, wherein the control unit, when power supply is restored and the fault information is stored in the memory unit, restarts the execution of the steam recovery process with power supply to the fan prohibited.

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