TW202003957A - washing machine - Google Patents

Abstract

A washing machine according to the present invention is provided with: a washing tub that is rotatably provided in a water tank; a water supply unit that supplies water into the water tank; a heating unit that heats the water stored in the water tank; a water level detection unit that detects the level of the water stored in the water tank; and a control unit that carries out a washing operation and a tank washing operation including a tank sterilization step in which the water stored in the water tank is heated by the heating unit, and the inside of the water tank is sterilized by means of steam generated through the heating. The control unit performs control, in the tank sterilization step, so as to set the first water level of the water stored in the water tank to be lower than the lowest water level set for the washing operation, and to be higher than a water level at which the lower end of the washing tub is in contact with the water surface.

Description

washing machine

Field of invention The present invention relates to a washing machine for washing clothes and the like.

Background of the invention Generally speaking, in a washing machine, detergent residue or dirt may accumulate on the inner surface of the water tank or the outer surface of the washing tank during long-term use. Bacteria or mold will use lotion residues or dirt as a nutrient source or habitat to reproduce. Thereby, after washing, an unpleasant odor may be generated from the washing machine or the clothes, or a part of the above-mentioned dirt may be attached to the washed clothes.

In addition, in order to improve the washing performance, there is a washing machine having a water spray function that spits out washing water to the laundry in the washing tub. In such a washing machine, there is a washing machine provided with a circulation water channel for circulating washing water in the water tank and discharging it into the washing tank. However, due to the difficulty in cleaning the circulating waterway, dirt and dirt will accumulate in the circulating waterway, and bacteria or molds will easily multiply their accumulations as habitats. Therefore, there may be cases where an unpleasant odor is generated in the circulating water channel, bacteria or mold adheres to the laundry, such metabolite or biofilm adhesion occurs, and the laundry is still dirty even though it has been washed.

In order to solve the above-mentioned dirt, Japanese Patent Laid-Open No. 2005-253584 proposes a washing machine that performs sterilization in a washing tank by the following procedure. That is, after the tank washing step is performed using a special detergent for washing the tank of the washing tank, etc., the air heated by the heating mechanism is sent into the washing tank by the air blowing mechanism To make the inside of the sink high temperature. In addition, a small amount of water is supplied to the heating mechanism or the washing tank to make the inside of the washing tank a high-temperature and humid environment, so as to sterilize the washing tank.

Summary of the invention However, in the above-described conventional configuration, members such as a water tank and a washing tank inside the washing machine, and water accumulated in the water tank are heated by passing through the heated air. In addition, when a small amount of water supplied to the heating mechanism or the tank is heated, the internal components of the washing machine are heated by permeating the air. In these heatings, since the thermal conductivity of air is lower than that of water or other substances, there is a problem that it takes time to increase the temperature of the entire water tank.

That is, when the water tank and the washing tank are heated by air, the water tank and the washing tank have a problem that the temperature rise is not easy due to the large heat capacity. In particular, the heat capacity of the washing tank provided in the water tank is large. Therefore, most of the heat generated by the heating mechanism will be used to increase the temperature of the water, and the temperature of the water will rise more rapidly than the temperature of the water tank and the washing tank. However, various sealing members and the like provided in the water tank or the washing tank have an upper limit on the usable temperature under the condition of heat resistance, so it is necessary to prevent an excessive rise in water temperature. In addition, as the water temperature of the water accumulated in the water tank becomes higher, the heat possessed by the water increases toward the outside of the washing machine through piping or the like connected to the drainage path or circulation path below the water tank.

The present invention is to solve the above-mentioned conventional problems, and its object is to provide a washing machine that can quickly raise the temperature in the water tank and efficiently sterilize the water tank.

In order to solve the aforementioned conventional problems, the washing machine of the present invention includes: a washing tank rotatably installed in the water tank; a water supply unit that supplies water to the water tank; a heating unit that heats the water stored in the water tank; a water level detection unit , To detect the water level of the water stored in the water tank; and the control unit to perform the washing operation and the tank cleaning operation including the tank sterilization step, the tank sterilization step is to make the heating unit heat the water accumulated in the water tank, and to Sterilize the water tank by heating the steam. In the tank sterilization step, the aforementioned control unit controls the first water level of the water accumulated in the water tank to be lower than the minimum water level set in the washing operation and more than the water level at which the lower end of the washing tank contacts the water surface high.

As a result, heat can be directly transferred from the heated water to the washing tank, and the washing tank can be efficiently heated. In particular, since the washing tub is the component with the largest mass and heat capacity among the components in the washing tub of the washing machine, by efficiently heating the washing tub, the temperature in the washing tub can be quickly increased. Therefore, it is possible to efficiently sterilize the water tank. In addition, in the tank sterilization step, by setting the first water level of the water accumulated in the water tank to be lower than the lowest water level set in the normal washing operation and contacting the water surface than the lower end of the washing tank Higher water levels can reduce the time and energy required for water heating.

The washing machine of the present invention can efficiently sterilize the water tank.

Forms for carrying out the invention The washing machine of the first invention includes: a washing tank rotatably installed in the water tank; a water supply unit that supplies water to the water tank; a heating unit that heats water stored in the water tank; a water level detection unit that detects accumulation in the water tank The water level of the water; and the control part, which performs the washing operation and the tank cleaning operation including the tank sterilization step, the tank sterilization step is to cause the heating part to heat the water accumulated in the water tank, and to generate Steam to sterilize the sink. In the tank sterilization step, the control unit controls the first water level of the water stored in the water tank to be lower than the minimum water level set in the washing operation and higher than the water level at which the lower end of the washing tank contacts the water surface .

With this, by setting the first water level of the water accumulated in the water tank to be higher than the water level at which the lower end of the washing tank contacts the water surface, it is possible to bring the water heated by the heating portion into contact with the washing tank. Therefore, it is possible to efficiently transmit the heat of the heating section to the washing tub through the heated water, and quickly raise the temperature in the water tub. In particular, since the mass and heat capacity of the washing tank disposed in the water tank are large, by efficiently heating the washing tank, the temperature in the water tank can be rapidly increased. As a result, the inside of the water tank can be sterilized efficiently. In addition, by setting the first water level of the water accumulated in the water tank to be lower than the lowest water level set in the normal washing operation and higher than the water level where the lower end of the washing tank is in contact with the water surface, it can be reduced The time and energy required for heating water.

In the second invention, especially in the first invention, the washing tank is driven to rotate about the horizontal axis, and the control unit controls the rotation of the water in the water tank by the heating unit during the tank sterilization step. Drive the sink.

As a result, the peripheral side of the washing tub can be gradually immersed in water, and the washing tub can be efficiently heated. Moreover, by the rotation of the washing tank, the warm water accumulated in the water tank is stirred, so the evaporation of the warm water or the heat exchange between the warm water and the air is promoted. As a result, the temperature and humidity in the water tank can be efficiently increased, and the water tank can be effectively sterilized.

According to a third invention, especially in the second invention, the washing tank is arranged obliquely, the control unit also performs a washing step of washing the water tank during the tank washing operation, and the control unit stores the water in the water tank during the washing step The second water level of the water is controlled so that the lower end of the high side of the washing tank will be immersed in water, and the washing tank will be controlled to rotate and drive at a higher speed than during the tank sterilization step.

In this way, in addition to the efficient sterilization of the water tank in the tank sterilization step, and in the rinsing step, by rotating the washing tank at a high speed with the second water level, it becomes possible to Wash extensively. Especially when the washing tank is inclined, for example, when it is inclined so that the front side becomes higher, by rotating the washing tank while the lower end of the front high side of the washing tank is immersed in water, the washing can be performed The entire circumferential side of the groove is in contact with water. As a result, the washing effect in the water tank can be improved.

The fourth invention is especially the invention according to any one of the first to third inventions. In the tank washing operation, the water tank and the washing tank are washed, and the control unit performs the tank sterilization step during the tank washing operation. Then perform the rinsing step of washing the sink.

By this, the temperature and humidity in the water tank can be increased by the steam generated in the water tank, and the bacteria or mold inhabiting the surface of the water tank and the washing tank can be killed by the damp heat above a certain temperature. In addition, the bacteria, molds, biofilms, etc. that have been killed in the tank sterilization step can be washed out and discharged to the outside of the machine after the tank sterilization step. As a result, during the next washing operation, it is possible to suppress the peeling of bacteria, mold, biofilm, etc. from the water tank or the washing tank and suppress their adhesion to the object to be washed, and wash the washing.

According to a fifth invention, particularly in the fourth invention, the washing machine includes: a circulating water channel provided to guide the water in the water tank from the bottom of the water tank toward the washing tank; and a pump to circulate the water in the water tank through the circulating water channel. During the tank washing operation, it will be controlled to drive the pump to circulate the water in the tank through the circulation water channel.

In this way, the heated water will flow through the circulating water channel, and the bacteria or mold inhabiting the circulating water channel can be killed. In addition, it is possible to peel off contaminated bacteria, molds, biofilms, etc. from the circulating water channel, and discharge it out of the machine. Therefore, it is possible to wash the piping surface of the wading environment that has high humidity and has become a habitat of bacteria or mold, and to suppress the adhesion of dirt to the object to be washed during the washing operation.

Sixth invention In particular, in the third invention, the water level of the second water level is higher than the first water level.

Thereby, the washing range in the rinsing step can be expanded to be wider than that in the tank sterilization step. As a result, the washing effect in the water tank can be improved. (Embodiment 1)

Fig. 1 is a schematic configuration diagram of a washing machine in a first embodiment of the present invention. FIG. 2 is a block diagram of the washing machine in this embodiment. Fig. 3 is a timing chart showing the operation of the washing machine during the tank washing operation in the embodiment. FIG. 4 is a graph showing the relationship between the water temperature and the sterilization effect in this embodiment. 5 is a schematic configuration diagram showing the main parts of the water level during the tank washing operation of the washing machine in this embodiment. 6 is a schematic diagram showing the water level and the water flow during the washing step of the washing machine in this embodiment.

In FIGS. 1 to 6, the washing machine of the present embodiment is a so-called drum-type washing machine in which the rotating shaft 3a of the drum 3, which is a washing tub, is set in the horizontal direction (including inclination). A water tank 2 that is elastically supported is provided in the housing 1. In the water tank 2, a drum 3 having a bottomed cylindrical shape, which is a washing tank, is provided so as to be rotatable about the rotation axis 3a of the horizontal axis. In the present embodiment, the rotation axis 3a of the drum 3 is at an angle θ (for example, 10 degrees), and the drum 3 is arranged to be inclined forward toward the front high side.

A plurality of baffles 4 and a plurality of small holes 5 are provided on the inner peripheral side of the drum 3, the plurality of baffles 4 protrude inward toward the center of rotation of the drum 3, and the plurality of small holes 5 are The water tank 2 communicates. An opening 6 is provided on the front side of the drum 3. The user puts in and takes out laundry such as laundry (hereinafter referred to as a laundry) through the opening 6 into the drum 3. Behind the water tank 2, a motor 7 that rotationally drives the drum 3 is arranged. The motor 7 is constituted by a brushless DC motor, and the rotation speed can be freely changed by inverter control.

The water supply pipe 8 for supplying water in the water tank 2 is connected to a faucet (not shown) of a water pipe, and a water supply valve 9 which is a water supply part is provided. The lotion box 10 into which the lotion is put is in communication with the water supply pipe 8. The lotion box 10 is in communication with the water tank 2 through the water supply path 11. As a result, the water flowing from the water supply pipe 8 through the detergent box 10 and the water supply path 11 flows into the water tank 2.

The washing water in the water tank 2 will be discharged to the outside of the machine through the drainage path 12. The drain path 12 has a drain valve 13 as a drain portion and a drain filter 14. The washing water is discharged from the drain port 15 provided at the bottom of the water tank 2 through the drain filter 14 through the opened drain valve 13 to the outside of the machine. The drain filter 14 is provided at a position where washing water circulates during the washing operation, and collects buttons and the like that fall off from the object to be washed. This drain filter 14 is configured to be detachable from the front side of the housing 1.

The circulating water channel 16 is provided to guide the washing water in the water tank 2 from the drain 15 toward the opening 6 side located in the front part of the water tank 2. The circulating water passage 16 is provided with a pump 17 that circulates washing water, and a discharge port 18. The pump 17 is provided on the bottom inside the casing 1 and is arranged on the downstream side of the drain filter 14. The discharge port 18 discharges the washing water into the drum 3 by driving the pump 17.

The heater 19 is a heating unit that heats the water stored in the water tank 2. The heater 19 is disposed at the bottom of the water tank 2, and when a predetermined amount of water is accumulated in the water tank 2, it will be submerged by the water. The water level detection unit 20 detects the water level of the washing water supplied into the water tank 2. The temperature detection unit 21 detects the temperature of the water in the water tank 2. In addition, the temperature detection unit 21 is formed of a thermistor or the like, and is disposed in the water immersion unit at the lower part of the water tank 2.

The control unit 22 is provided in the casing 1 and controls various components according to the input information to perform a washing operation, a tank washing operation, and the like. Specifically, as shown in the block diagram of FIG. 2, in the control unit 22, the following is input as information: the amount of the laundry detected by the cloth amount detection unit 23, and the water level detection unit 20 The detected water level of the washing water, the temperature of the water detected by the temperature detection unit 21, the driving amount (for example, the number of rotations) of the drum 3 detected by the rotation detection unit 24, and the like. The control unit 22 controls the motor 7, the water supply valve 9, the drain valve 13, the pump 17, the heater 19, etc. according to these inputs, and sequentially controls the washing step, rinsing step, dehydration step, etc. to perform the washing operation.

In addition, as will be described later, the control unit 22 performs a tank washing operation for washing the water tank 2 and the drum 3. The tank cleaning operation includes at least a tank sterilization step and a rinse step. The tank sterilization step is to heat the water stored in the water tank 2 by the heater 19, and sterilize the water tank 2 with the generated steam. The rinsing step is performed after the tank sterilization step, and the water tank 2, the drum 3, the circulating water channel 16, and the like are washed.

In addition, the user can take out the laundry from the opening 6 provided on the front side of the drum 3 by opening the freely openable door 25 provided on the front side of the housing 1. In addition, an operation display unit 26 is provided on the upper portion of the front side of the housing 1. The user can perform settings for operating the washing machine by operating the display unit 26. In addition, the operation display unit 26 displays the setting contents, the operation status, and the like.

The operation and effect of the washing machine configured as above will be described below.

First, the washing operation for washing laundry will be described. The washing operation includes at least a washing step, a washing step, and a dehydration step.

The user opens the door 25 and throws the object to be washed from the opening 6 into the drum 3. Next, the user turns on the power switch (not shown) of the operation display unit 26 and operates the start switch (not shown) to start the operation.

First, the cleaning step is performed. After the operation is started, the control unit 22 detects the amount of laundry to be put into the drum 3 by the cloth amount detection unit 23. The amount of the laundry can be detected from the amount of torque applied to the motor 7 or the current value of the motor 7 when the drum 3 rotates. The control unit 22 sets the amount of water supplied to the water tank 2 according to the detected amount of laundry. In addition, the control unit 22 sets the time to execute each step of the washing operation. In addition, the control unit 22 determines the washing amount to be the reference amount from the washing amount previously set according to the amount of the object to be washed, and displays it on the operation display unit 26. The user puts the lotion into the lotion box 10 according to the displayed lotion amount.

Next, the control unit 22 opens the water supply valve 9. As a result, water from the tap water pipe is supplied into the water tank 2 through the detergent box 10. The water that enters the detergent box 10 through the water supply pipe 8 dissolves the detergent that has been put into the detergent box 10 and is supplied into the water tank 2 as washing water. At this time, since the drain valve 13 has been closed, the wash water will accumulate in the bottom of the water tank 2. The washing water accumulated in the bottom of the water tank 2 flows into the drum 3 through the small hole 5.

Next, the control unit 22 detects the amount of water supplied into the water tank 2 by the water level detection unit 20. The control unit 22 closes the water supply valve 9 after judging that the amount of water that has been supplied has reached the predetermined amount of water set according to the amount of the object to be washed. In addition, during water supply, the control unit 22 rotates and drives the drum 3 in one direction at the number of rotations (for example, 20 rpm) at which the object to be washed rotates in the drum 3. In this way, the penetration of the washing water into the object to be washed can be accelerated. In addition, the water level of the washing water in the water tank 2 is lowered from the set water level due to the absorption of the washing water to the object to be washed. Therefore, the control part 22 will open the water supply valve 9 again, and replenish the inside of the washing tank 2 to return the water level of the washing water to the set water level.

Next, the control unit 22 drives the pump 17 after the water supply is completed. As a result, the water accumulated in the bottom of the water tank 2 is guided from the drain 15 to the circulating water channel 16. The water flowing into the circulating water channel 16 flows through the circulating water channel 16 and is discharged into the drum 3 from the discharge port 18. As a result, the washing water that has penetrated into the object to be washed flows out from the small hole 5 into the water tank 2 and circulates in the path from the drain 15 through the circulation water path 16.

Next, the control unit 22 drives the drum 3 to alternately rotate forward and reverse at a predetermined number of rotations (for example, 42 rpm) every predetermined time by the motor 7 to perform the cleaning of the object to be washed. In the flap cleaning, the object to be washed is lifted toward the rotation direction of the drum 3 by the baffle 4 and then washed from the upper part of the drum 3 to wash. The control unit 22 executes the cleaning step described above for a predetermined time (for example, 10 minutes). After that, the control unit 22 opens the drain valve 13 to discharge the washing water to the outside of the machine, and ends the washing step. After the washing step, the control unit 22 sequentially executes the washing step and the dehydrating step, and ends the washing operation. The detailed description of the rinse step and the dehydration step is omitted.

In addition, the aforementioned washing water is a general term for water used in a washing machine. That is, the washing water includes: water that does not contain detergent supplied to the washing machine, washing water that contains detergent that has been put in, washing water that rinses off detergent components, dirt, and the like in the washing step.

Next, the tank washing operation will be described. The tank washing operation is performed separately from the washing operation, and the water tank 2, the drum 3, the circulating water passage 16, and the like are washed. The tank cleaning operation has at least a tank sterilization step, a drainage step, a rinsing step, and a drainage step, and these steps will be executed in sequence.

The user turns on the power switch (not shown) of the operation display unit 26, and after the set tank washing operation, operates the start switch (not shown) to start the operation. First, the tank sterilization step is performed.

After starting the tank sterilization step, the control unit 22 opens the water supply valve 9 as shown in the timing chart of FIG. 3. As a result, the water from the tap water pipe is supplied into the water tank 2 through the water supply pipe 8 through the detergent box 10. At this time, since no detergent is put into the detergent box 10, water not containing detergent is supplied into the water tank 2. The water accumulated in the bottom of the water tank 2 flows into the drum 3 from the small hole 5.

Next, the control unit 22 uses the water level detection unit 20 to detect the amount of water supplied into the water tank 2. The control unit 22 supplies water to the predetermined water level L1 according to the output of the water level detection unit 20 and closes the water supply valve 9. The water level L1 is set to be higher than the water level at which the lower end 3b of the rear side of the drum 3 is in contact with the water surface (see FIG. 5) and lower than the lowest water level to be supplied in the normal washing operation. In addition, the water level L1 is a water level at which the heater 19 will be immersed in water.

Next, after supplying water, the control unit 22 controls the energization of the heater 19 according to the output of the temperature detection unit 21 to heat the water accumulated in the bottom of the water tank 2. As a result, steam is generated in the water tank 2. At this time, since the heated water is in contact with the lower portion of the drum 3, the drum 3 is directly heated by warm water. Therefore, the drum 3 having a large mass and heat capacity can be efficiently heated, and the temperature in the water tank 2 can be quickly increased.

Next, the control unit 22 rotates the drum 3 at a low speed (for example, 20 rpm) at almost the same time or from the front and back of the heater 19. With this, the peripheral side surface of the drum 3 can be heated as a whole with warm water. In addition, the heated water is stirred to promote steam generation. That is, in the temperature increase caused by the heating of the water in the water tank 2, the drum 3 is driven to rotate, and the water tank 2 can be quickly heated from a low temperature stage.

In this way, by heating the inside of the water tank 2, the inside of the water tank 2 can be sterilized. It is preferable that the temperature in the water tank 2 for sterilization is increased to 50 degrees or more and 90 degrees or less. In general, the higher the temperature, the more beneficial the sterilization of mold or bacteria. However, when the temperature is set to a predetermined temperature or higher, it is necessary to consider the heat resistance temperature of the resin material, which is the structure of the washing machine. In addition, it takes time to heat the supplied water to a high temperature. Therefore, in order to achieve the same sterilization effect as at high temperature even in a shorter time and at a low temperature, as described above, it is desirable to raise the temperature in the water tank 2 to 50 degrees or more and 90 degrees or less.

Fig. 4 shows the relationship between the heating temperature and holding time (horizontal axis) and the sterilization effect (vertical axis) for mold. The relationship of the heating temperature in FIG. 4 is temperature a<temperature b<temperature c. For example, temperature a=45 degrees, temperature b=48 degrees, and temperature c=50 degrees.

The lower the heating temperature becomes, the longer it takes for the mold or bacteria to die. It can be confirmed that in order to reduce the number of inhabiting molds or bacteria in a shorter time, the higher the heating temperature, the more advantageous.

For example, compare the time required to reduce the number of bacteria from 1.0E+07 to 1.0E+05. Relative to more than 10 minutes at temperature a, it is shortened to less than 5 minutes at temperature c. In addition, the number of bacteria reduced at the same holding time was compared. During the holding time of 0 minutes to 5 minutes, the bacterial count decreased from 1.0E+07 to 1.0E+06 at temperature a, and the bacterial count decreased from 1.0E+07 to less than 1.0E+02 at temperature c. Therefore, in this embodiment, the heating temperature for mold is set to 50 degrees.

The control unit 22 detects the temperature of the washing water in the water tank 2 by the temperature detection unit 21. After detecting that the water temperature has reached the set temperature T1, the control unit 22 controls the heater 19 to maintain the temperature near the set temperature T1 for a predetermined time. For example, when the set temperature T1 is 55 degrees, the control unit 22 turns off the heater 19 after the water temperature reaches 55 degrees. In addition, after the water temperature drops to 53 degrees, the control unit 22 turns on the heater 19. As described above, by turning ON or OFF the heater 19, the temperature in the water tank 2 can be maintained at 50 degrees or more. In addition, after the water temperature reaches the set temperature T1, the control unit 22 continues to rotate the drum 3 until the tank sterilization step is completed.

In addition, when the water temperature reaches the set temperature T1, the control unit 22 drives the pump 17. As a result, as described below, the heated water in the water tank 2 flows to the circulating water channel 16 to circulate. The heated water in the water tank 2 is attracted from the drain 15 provided at the bottom of the water tank 2, and is guided to the circulating water channel 16 through the drain filter 14. The water flowing into the circulation water channel 16 is discharged from the discharge port 18 into the drum 3. Then, the water discharged into the drum 3 flows out from the small hole 5 into the water tank 2 and circulates in the path from the drain 15 through the circulation water channel 16.

As described above, by heating water flowing through the path through the circulation water channel 16 to circulate, the bacteria or mold inhabiting the path through the circulation water channel 16 can be killed and sterilized. At this time, it is preferable that the control unit 22 drives the pump 17 at a low speed to allow bacteria or mold to contact the heated water for a long time. Specifically, as long as the heated water does not stay in the path passing through the circulating water channel 16, the heated water may be circulated at a speed sufficient to flow. The driving of the pump 17 may be continuous or intermittent.

The control unit 22 executes the above-mentioned tank sterilization step for a predetermined time set in advance (for example, 10 minutes after the water temperature reaches the set temperature T1), and then stops the energization of the heater 19.

Then, after the tank sterilization step, the control unit 22 executes the drainage step. In the drainage step, the heated water used in the tank sterilization step will be drained. For this, the control unit 22 opens the drain valve 13. As a result, the heated water will drain from the drain 15 through the drain path 12 to the outside of the machine.

Then, after the tank sterilization step and the drainage step, the control unit 22 executes the rinsing step. In the rinsing step, contaminants such as bacteria, molds, biofilms, etc. that have been killed in the tank sterilization step are stripped from the wall surface of the water tank 2 or the drum 3 and washed away. The details of the rinsing procedure will be described below.

First, the control unit 22 opens the water supply valve 9 and supplies water to the water tank 2 to a predetermined water level L2 according to the output of the water level detection unit 20. This is shown in the schematic configuration diagram of FIG. 5. The predetermined water level L2 is higher than the predetermined water level L1 during the tank sterilization step. For example, in the drum 3 inclined so that the front side (left side in FIG. 5) becomes higher, the water level L2 is a water level set so that the lower end 3c on the high side will be immersed in water.

The control unit 22 detects the amount of water supplied into the water tank 2 by the water level detection unit 20. The control unit 22 will supply water to the predetermined water level L2 according to the output of the water level detection unit 20 and close the water supply valve 9. When the water is accumulated in the water tank 2 to the predetermined water level L2, the lower part of the drum 3 will be fully immersed in water. In addition, the water level detection unit 20 may detect the water levels L1 and L2 by detecting the amount of water supplied into the water tank 2.

After the water has accumulated to the predetermined water level L2, the control unit 22 will rotationally drive the drum 3 at a higher speed (for example, 100 rpm) than during the tank sterilization step. As a result, the water in the water tank 2 is rolled upward by the high-speed rotation of the drum 3 and reaches the top of the water tank 2. As shown in FIG. 6, in the drum 3 inclined upward on the front side (left side in FIG. 6 ), since the lower end 3 c on the higher side is immersed in water, the entire drum 3 can be washed.

As described above, after the tank sterilization step, the control unit 22 executes the rinsing step. This makes it possible to remove dirt, such as bacteria, molds, and biofilms that have been killed in the tank sterilization step, from the wall surface of the water tank 2 or the drum 3, and to wash them away.

At this time, when the water level detection unit 20 detects the predetermined water level L2, the control unit 22 closes the water supply valve 9 and drives the pump 17. As a result, the water in the water tank 2 flows through the circulation water channel 16 and circulates, and dirt such as bacteria, mold, and biofilm that have been killed in the sterilization step can be peeled from the wall surface in the circulation water channel 16. The control unit 22 executes the above-mentioned rinsing step for a predetermined time (for example, 30 minutes) set in advance, and then stops the rotation drive of the drum 3.

Finally, after the rinsing step, the control section 22 will perform the drainage step. In the drainage step, the water in the water tank 2 and the circulating water channel 16 will be drained out of the machine. The water in the water tank 2 and the circulating water channel 16 contains dirt, such as bacteria, mold, and biofilm, which have been killed in the tank sterilization step.

The control unit 22 opens the drain valve 13 to drain the water in the water tank 2 and the circulating water channel 16. After that, the drum 3 is rotated at a high speed (for example, 300 rpm) for a short time. As a result, water droplets and the like attached to the drum 3 are discharged to the outside of the machine, and the control unit 22 ends the draining step and completes the tank washing operation.

As described above, the washing machine of this embodiment includes: the drum 3, which is rotatably installed in the water tank 2; the water supply valve 9, which supplies water to the water tank 2; and the heater 19, which heats the water stored in the water tank 2 ; The water level detection unit 20 detects the water level of the water accumulated in the water tank 2; and the control unit 22 performs the washing operation and the tank cleaning operation including the tank sterilization step, the tank sterilization step is to cause the heating unit to accumulate in the water tank The water inside is heated, and the steam generated by heating is used to sterilize the water tank. In the tank sterilization step, the control unit 22 controls the first water level L1 of the water accumulated in the water tank 2 to be lower than the lowest water level set in the washing operation and to be in contact with the water surface than the lower end 3b of the drum 3 The water level is higher. When the drum 3 is inclined, the first water level L1 is higher than the water level at which the lower end of the drum 3 is in contact with the water surface.

Thereby, by the water heated by the heater 19 coming into contact with the drum 3, the heat of the heater 19 can be efficiently transmitted to the drum 3. Then, the temperature in the water tank 2 can be quickly increased by the heat release of the drum 3. As a result, the inside of the water tank 2 can be sterilized efficiently. In particular, since the mass and heat capacity of the drum 3 disposed in the water tank 2 are large, the temperature in the water tank 2 can be rapidly increased by efficiently heating the drum 3. In addition, in the tank sterilization step, by setting the water level of the water accumulated in the water tank 2 to be lower than the lowest water level set in the normal washing operation and contacting the water surface than the lower end 3b of the drum 3 Higher water levels can reduce the time and energy required for water heating.

In addition, the drum 3 is driven to rotate about the horizontal axis, and in the tank sterilization step, the control unit 22 controls the drum 3 to be driven to rotate while the temperature of the water in the water tank 2 rises.

With this, the peripheral side surface of the drum 3 can be gradually immersed in water, and the drum 3 can be efficiently heated. In addition, since the warm water can be stirred by the rotation of the drum 3, the evaporation of the warm water or the heat exchange between the warm water and the air is promoted. As a result, the temperature and humidity in the water tank 2 can be efficiently increased, and the water tank 2 can be effectively sterilized.

In addition, the drum 3 is disposed obliquely, and the controller 22 also performs a washing step of washing the water tank 2 during the tank washing operation. In the rinsing step, water is supplied to the second water level L2 where the lower end 3c of the high side of the drum 3 is immersed in water, and the drum 3 is rotationally driven at a higher speed than in the tank sterilization step.

Thereby, in the tank sterilization step, the water tank 2 can be sterilized efficiently. In addition, in the rinsing step, by setting to rotate at a high water level at high speed, it becomes possible to wash a wide range in the water tank 2. As a result, the washing effect in the water tank 2 can be improved. In particular, when the drum 3 is inclined, for example, when it is inclined so that the front side becomes higher, the drum 3 can be rotated by rotating the drum 3 with the lower end 3c of the front high side of the drum 3 submerged in water. The entire peripheral surface of the drum 3 is in contact with water.

In the tank washing operation, the water tank 2 and the drum 3 are washed. In the tank washing operation, the control unit 22 executes the rinsing step after the tank sterilization step.

In this way, the bacteria, mold, biofilm, etc. that have been killed in the tank sterilization step can be washed away in the washing step and discharged out of the machine. As a result, in the next washing operation, it is possible to suppress the peeling of bacteria, mold, biofilm, etc. from the water tank 2 or the drum 3 and suppress their adhesion to the object to be washed, and wash the laundry.

In addition, the washing machine includes: a circulation water channel 16 provided to guide the water in the water tank 2 from the bottom of the water tank 2 into the drum 3; and a pump 17 to circulate the water in the water tank 2 through the circulation water channel 16, and the control unit 22 During the tank washing operation, the pump 17 is driven to circulate the water in the water tank 2 through the circulation water channel 16.

In this way, by flowing the heated water to the circulating water channel 16, the bacteria or mold inhabiting the circulating water channel 16 can be killed, and the dead bacteria, mold, biofilm, etc. can be removed from the circulating water channel 16 Peel off and expel it out of the machine. Therefore, it is possible to wash the piping surface of the wading environment that has high humidity and has become a habitat of bacteria or mold, and to suppress the adhesion of dirt to the object to be washed during the washing operation.

In addition, the water level of the second water level L2 in the rinsing step is higher than the first water level L1 in the tank sterilization step.

Thereby, the washing range in the rinsing step can be expanded to be wider than that in the tank sterilization step. As a result, the washing effect in the water tank 2 can be improved. (Embodiment 2)

7 is a schematic configuration diagram of a washing machine in a second embodiment of the present invention. The feature of this embodiment is that a part of the washing machine of the first embodiment is applied to a so-called upright washing machine in which the rotation axis of the washing tub 3 is set in the vertical direction (vertical direction in FIG. 7). In the configuration of the present embodiment, the same configuration as that of the first embodiment is given the same symbol, and the detailed description will refer to the first embodiment.

In FIG. 7, the washing tank 3 is rotatably provided in the water tank 2. The stirring blade 27 is rotatably provided in the bottom of the washing tank 3. The stirring blade 27 is rotationally driven by the motor 7 and stirs the washing water accumulated in the water tank 2.

In the upright washing machine of this embodiment, as in the first embodiment, the control unit 22 controls the tank washing operation for washing the water tank 2, the washing tank 3, and the like. The tank cleaning operation is performed separately from the washing operation, and has at least a tank sterilization step, a drainage step, a rinsing step, and a drainage step, and these steps are executed in sequence.

In the tank sterilization step, the control unit 22 uses the water level detection unit 20 to detect the amount of water supplied into the water tank 2. The control unit 22 will supply water to the water tank 2 until the predetermined water level L1 according to the output of the water level detection unit 20 and close the water supply valve 9. The predetermined water level L1 is set to be higher than the water level at which the lower end of the washing tank 3 is in contact with the water surface, and lower than the lowest water level to be supplied in the normal washing operation.

After supplying water, the control unit 22 controls the energization of the heater 19 according to the output of the temperature detection unit 21 to heat the water stored in the bottom of the water tank 2. As a result, steam is generated in the water tank 2. At this time, since the heated water is in contact with the lower part of the washing tub 3, the washing tub 3 is directly heated by warm water. Therefore, the washing tub 3 having a large mass and a large heat capacity can be efficiently heated, and the temperature in the water tub 2 can be quickly increased.

Next, the control unit 22 rotates and drives the stirring blade 27 almost simultaneously or from front to back of the heater 19. By this rotational drive, the washing water accumulated in the water tank 2 is stirred. With this, the peripheral side surface of the washing tub 3 can be heated as a whole with warm water. In addition, the heated water is stirred to promote steam generation. That is, in the temperature increase caused by the heating of the water in the water tank 2, the inside of the water tank 2 can be quickly heated from a low temperature stage. In this way, by heating the inside of the water tank 2, the inside of the water tank 2 can be sterilized.

Next, the control unit 22 detects the temperature of the washing water in the water tank 2 by the temperature detection unit 21. After detecting that the water temperature has reached the set temperature T1, the control unit 22 controls the heater 19 to be turned ON or OFF to maintain the temperature near the set temperature T1 for a predetermined time. In this way, by heating the inside of the water tank 2, the bacteria or mold inhabiting the wall surfaces of the water tank 2 and the washing tank 3 are killed.

The control unit 22 executes the above-mentioned tank sterilization step for a predetermined time set in advance (for example, 10 minutes after reaching the set temperature T1), and then stops the energization of the heater 19.

Then, after the tank sterilization step, the control unit 22 executes the drainage step. In the drainage step, the heated water used in the tank sterilization step will be drained. For this, the control unit 22 opens the drain valve 13. As a result, the heated water is drained out of the machine through the drain path 12 from the drain port (not shown).

Then, after the tank sterilization step and the drainage step, the control unit 22 executes the rinsing step. In the rinsing step, the dirt, bacteria, mold, biofilm, etc. that have been killed in the tank sterilization step will be stripped off and washed away from the wall surface of the water tank 2 or the washing tank 3.

First, the control unit 22 opens the water supply valve 9 and supplies water to the water tank 2 up to a predetermined water level L2 according to the output of the water level detection unit 20, and then closes the water supply valve 9. Next, the control unit 22 rotates the stirring blade 27 at high speed. By this rotational drive, water flow will be generated in the water tank 2. Then, the surrounding of the water surface rises into a V shape, and the dirt such as bacteria, molds, and biofilms that have been killed in the tank sterilization step is washed away. At this time, the water level L2 of the water accumulated in the water tank 2 is preferably higher than the water level L1 of the water accumulated in the water tank 2 in the tank sterilization step.

Finally, after the rinsing step, the control unit 22 executes the drainage step, and ends the tank washing operation. In the drainage step, the water in the water tank 2 is drained out of the machine. The water in the water tank 2 contains contaminants such as bacteria, molds, and biofilms that have been killed in the tank sterilization step. The control unit 22 opens the drain valve 13 to drain the water in the water tank 2. In addition, the stirring blade 27 may be driven to rotate integrally with the washing tub 3.

As described above, the washing machine of this embodiment includes: the washing tank 3, which is rotatably installed in the water tank 2; the water supply valve 9, which supplies water to the water tank 2; and the heater 19, which stores the water stored in the water tank 2 Heating; the water level detection unit 20 detects the water level of the water accumulated in the water tank 2; and the control unit 22 executes a washing operation and a tank cleaning operation including a tank sterilization step. The water in the water tank is heated, and the steam generated by heating is used to sterilize the water tank. In the tank sterilization step, the control unit 22 controls the first water level L1 of the water accumulated in the water tank 2 to be lower than the lowest water level set in the washing operation and to contact the water surface than the lower end of the washing tank 3 The water level is higher.

By this, by contacting the water heated by the heater 19 with the washing tub 3, the heat of the heater 19 can be efficiently transmitted to the washing tub 3. Then, the temperature in the water tank 2 can be quickly increased by the heat release from the washing tank 3. As a result, the inside of the water tank 2 can be sterilized efficiently. In particular, since the mass and heat capacity of the washing tank 3 disposed in the water tank 2 are large, by efficiently heating the washing tank 3, the temperature in the water tank 2 can be rapidly increased. In addition, in the tank sterilization step, by setting the water level of the water accumulated in the water tank 2 to be lower than the lowest water level set in the normal washing operation and contacting the water surface than the lower end of the washing tank 3 Higher water levels can reduce the time and energy required for water heating.

As described above, since the washing machine of the present invention can efficiently sterilize the water tank, it is useful as a washing machine.

1‧‧‧Housing 2‧‧‧Sink 3‧‧‧Drum (washing tank) 3a‧‧‧rotation axis 3b, 3c‧‧‧lower 4‧‧‧Baffle 5‧‧‧Eye 6‧‧‧Opening 7‧‧‧Motor 8‧‧‧Water supply piping 9‧‧‧Water supply valve 10‧‧‧Lotion box 11‧‧‧ Water supply road 12‧‧‧Drainage path 13‧‧‧Drain valve 14‧‧‧Drain filter 15‧‧‧Drain 16‧‧‧Circulation waterway 17‧‧‧Pump 18‧‧‧spit out 19‧‧‧ Heater 20‧‧‧Water level detection department 21‧‧‧Temperature Detection Department 22‧‧‧Control Department 23‧‧‧cloth quantity detection department 24‧‧‧rotation detection department 25‧‧‧ door 26‧‧‧Operation display section 27‧‧‧Wing a, b, c ‧‧‧ temperature L1‧‧‧First water level L2‧‧‧2nd water level T1‧‧‧Set temperature θ‧‧‧angle

FIG. 1 is a schematic configuration diagram of a washing machine in Embodiment 1 of the present invention. 2 is a block diagram of a washing machine in Embodiment 1 of the present invention. 3 is a time chart showing the operation of the washing machine in Embodiment 1 of the present invention. 4 is a graph showing the relationship between the water temperature and the sterilization effect in Embodiment 1 of the present invention. 5 is a schematic configuration diagram showing the main parts of the water level during the tank washing operation of the washing machine in Embodiment 1 of the present invention. 6 is a schematic diagram showing the water level and the water flow during the washing step of the washing machine in Embodiment 1 of the present invention. 7 is a schematic configuration diagram of a washing machine in Embodiment 2 of the present invention.

1‧‧‧Housing

2‧‧‧Sink

3‧‧‧Drum (washing tank)

3a‧‧‧rotation axis

4‧‧‧Baffle

5‧‧‧Eye

6‧‧‧Opening

7‧‧‧Motor

8‧‧‧Water supply piping

9‧‧‧Water supply valve

10‧‧‧Lotion box

11‧‧‧ Water supply road

12‧‧‧Drainage path

13‧‧‧Drain valve

14‧‧‧Drain filter

15‧‧‧Drain

16‧‧‧Circulation waterway

17‧‧‧Pump

18‧‧‧spit out

19‧‧‧ Heater

20‧‧‧Water level detection department

21‧‧‧Temperature Detection Department

22‧‧‧Control Department

23‧‧‧cloth quantity detection department

24‧‧‧rotation detection department

25‧‧‧ door

26‧‧‧Operation display section

Claims (6)

A washing machine with: The washing tank can be rotatably set in the water tank; The water supply department supplies water to the aforementioned water tank; A heating unit that heats the water stored in the water tank; The water level detection unit detects the water level of the water stored in the water tank; and The control unit performs a washing operation and a tank cleaning operation including a tank sterilization step, wherein the tank sterilization step causes the heating unit to heat the water accumulated in the water tank and use steam generated by the heating to Sterilize the aforementioned water tank, In the tank sterilization step, the control unit controls the first water level of the water stored in the water tank to be lower than the lowest water level set in the washing operation and contacting the lower end of the washing tank The water level above the water surface is higher. The washing machine according to claim 1, wherein the washing tank is driven to rotate about the horizontal axis, and the control unit controls the water in the water tank by the heating unit in the tank sterilization step During the temperature increase, the washing tank is driven to rotate. According to the washing machine of claim 2, wherein the washing tank is arranged obliquely, the control unit may also perform a washing step of washing the water tank during the washing operation of the tank. During the washing step, the control unit may The second water level of the water accumulated in the water tank is controlled so that the lower end of the high side of the washing tank is immersed in water, and the washing tank is controlled to rotate and drive at a higher speed than in the tank sterilization step. The washing machine according to any one of claims 1 to 3, which performs the washing of the water tank and the washing tank during the washing operation of the tank, and the control unit removes the washing tank during the washing operation of the tank After the bacteria step, a rinsing step for washing the aforementioned water tank is performed. The washing machine of claim 4, wherein the aforementioned washing machine has: A circulating water path provided to guide the water in the water tank from the bottom of the water tank toward the washing tank; and A pump to circulate the water in the water tank through the circulation water channel, During the tank cleaning operation, the control unit controls the pump to circulate the water in the water tank through the circulation water channel. The washing machine of claim 3, wherein the water level of the second water level is higher than the first water level.

Images