JPH04122294A - Washing machine - Google Patents

Abstract

PURPOSE:To sufficiently suppress the breakage of a washed article and increase the rising speed of water temperature by installing a control means for intensifying the intensity of a weak water stream according to the rise of the detection result of the water temperature in a water tank until the detection result reaches a prescribed temperature. CONSTITUTION:A water temperature detector 28 which detects the temperature of water in an outer tank 2 by detecting the temperature of a heater installation metal fitting 270 for boiling water is installed. In this case, the control for increasing the intensity of the water stream according to the rise of the detection result until the detection result reaches a prescribed temperature is carried out. Accordingly, though a weak water stream is generated until the detected water temperature in the water tank reaches a prescribed temperature, the water stream in this case is the weak water stream which is intensified according to the rise of the water temperature. Accordingly, when the water temperature is low, the water stream is exceedingly weak, and the water stream is intensified according to the rise of the water temperature, without generating the unnecessary breakage on a washed article, and the rising speed of the water temperature can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a washing machine that performs washing by heating water in a water tank.

[Prior art]

Conventional washing machines are equipped with a water heater that heats the water supplied into a water tank that stores washing water.When washing, the water heater is turned on and the water in the water tank is heated to a preset temperature. Some methods increase the water temperature and utilize the characteristics of detergents to improve the washing effect.

In a washing machine equipped with a boiling heater, the water temperature is raised to a preset temperature during the washing process, but if the water is washed with a constant stream of strong water while the water temperature is rising, the laundry will become more damaged. There is also the problem that if a water flow is not generated while the water temperature is rising, a temperature difference will occur between the upper and lower sides of the washing water in the tank, and the rate of rise in water temperature will be slow.

One way to solve this problem is to create a washing machine that generates a constant weak water flow to agitate the washing water when the water temperature is rising, and then switches the water flow to a constant strong water flow when the water temperature reaches a predetermined temperature. A machine is disclosed in Japanese Patent Publication No. 51-23825.

[Problem to be solved by the invention]

However, in the conventional washing machine disclosed in Japanese Patent Publication No. 51-23825 as mentioned above, the weak water flow generated when the water temperature rises is a water flow of constant strength, and a water flow of the same strength is generated regardless of the water temperature. Therefore, it is necessary to sufficiently suppress damage to the laundry (If the weak water flow is set to a weak strength, the rate of increase in water temperature will be slow; If the strength of the weak water flow is set to be close to the strong water flow, it is difficult to suppress damage to the laundry.For this reason, in order to suppress damage to the laundry and improve the rate of increase in water temperature, it is necessary to set the weak water flow to a strength close to that of the strong water flow. The water flow strength must be set to a value between the strength that sufficiently suppresses damage to the laundry and the strength that increases the rate of increase in water temperature sufficiently.If the weak water flow is set to such a strength, the laundry There was a problem in that both the suppression of damage to water and the improvement in the rate of increase in water temperature were insufficient.

The present invention has been made in view of the above circumstances, and by changing the intensity of the weak water flow according to the water temperature while the water temperature is rising, damage to laundry can be sufficiently suppressed and the rate of increase in water temperature can be reduced. The purpose of the present invention is to provide a washing machine that realizes further improvements in the following.

[Means to solve the problem]

The washing machine according to the present invention generates a weak water flow in the water tank while heating the water in the water tank, and when the water temperature reaches a predetermined temperature, switches the water flow in the water tank to a strong water flow. In the washing machine, there is provided a means for detecting the water temperature in the water tank, a means for comparing the detection result of the means with the predetermined temperature, and a means for comparing the detection result of the water tank with the predetermined temperature, and a means for comparing the detection result of the water tank with the predetermined temperature until the detection result reaches the predetermined temperature. and control means for increasing the strength of the weak water flow.

[Effect]

A weak water flow is generated in the aquarium until the detected water temperature in the aquarium reaches a predetermined temperature, but in this case, the water flow is
The weak water flow is strengthened as the water temperature increases, so when the water temperature is low, the water flow is extremely weak and does not cause unnecessary damage to the laundry, and the water temperature increases. The water flow is strengthened accordingly, and the stirring power of the water in the tank increases, so that the difference in water temperature at each location in the tank is reduced until the predetermined temperature is reached.

〔Example〕

The present invention will be specifically described below based on drawings showing embodiments thereof.

FIG. 1 is a schematic perspective view of a washing machine according to the present invention. In the figure, numeral 1 is a frame made of sheet metal in the shape of a prism with a bottom. The front edge of the upper surface of the frame 1 is an upper panel made of synthetic resin that accommodates equipment such as electronic components, and is equipped with a keyboard 11 on the upper surface of which is provided with various operation keys to be described later. At the rear edge of the upper surface of the frame 1, there is a housing section 9 that is a synthetic resin top plate that houses equipment such as a water supply device.
b are respectively expanded. Further, a rectangular upper clothing input port 10a is provided between the operating portion 9a and the storage portion 9b on the upper surface of the frame 1, and the upper clothing input port 10a is arranged in the direction indicated by the white arrow in the figure. A synthetic resin top lid I4 that opens and closes is provided. Inside the frame 1, an outer tank 2, which is a synthetic resin water tank formed in the shape of a horizontal drum, is disposed. 3 is disposed coaxially and rotatably with the outer tank 2.

FIG. 2 is a vertical sectional view of the outside of the outer tub 2 of the washing machine according to the present invention, viewed from the front. The outer tank 2 has a flat bottom 2C, an outwardly curved side 2b, and a horizontal drum shape with an upper part 2a projecting upward into a rectangular tube shape.
An intermediate clothing input port 10b is provided in the upper portion 2a. The upper clothing input port 1. Oa and the intermediate clothing input port 10b are watertightly connected by a rubber gasket I2. Further, a horizontal support portion 20.20 whose lower surface is flat is formed protrudingly from the lower part of the side portions 2b, 2b of the outer tank 2, and an iron mounting plate is attached to the bottom surface of the horizontal support portion 20.20. A plate 2929 is fixed. In the frame 1, the upper parts of the side parts 2b, 2b of the outer tank 2 are elastically suspended and supported from the four upper corners of the frame 1 by upper supports 5, 5, . . . made of elastic members. On the other hand, the lower part of the outer tank 2 is attached to lower supports 6, 6 made of elastic members disposed between the plates 29 and 29 and the bottom of the frame 1.
It is supported by...

At the center of the front wall of the outer tank 2, a heater casing 40 having a generally teardrop shape when viewed from the front is disposed. The heater casing 40 has 3 parts inside the heater casing 40 from the outside.
The drying heater 4, which has a heating element formed in a horseshoe shape along the side wall of the heater casing 40, is fitted with two mounting brackets 41, 41.41.
．． It is fixed within the heater casing 40 at 41.

A circulation duct 21 is integrally formed on the left side of the heater casing 40 when viewed from the front, and communicates with the inside of the outer tank 2 through a circulation port (not shown) opened in the front wall of the outer tank 2 and extends upward. . At the top of this circulation duct 21 is a blower fan 22.
A connecting pipe 42 is provided between the upper part of the circulation duct 21 and the heater casing 40, and the inside of the circulation duct 21 and the inside of the heater casing 40 communicate with each other via the connecting pipe 42. has been done.

Further, on the right side of the heater casing 40 when viewed from the front, there is an overflow port (not shown) opened at a height position 172 on the front wall.
An overflow chamber 23 is provided for discharging overflow water from the overflow chamber 23, and an overflow hose 230 for draining overflow water in the overflow chamber 23 is connected to the bottom of the overflow chamber 23. An air trap 24 for detecting the water level in the outer tank 2 is integrally formed at the outer lower part of the front wall of the outer tank 2. This air trap 24 is connected to a water level detector 2 disposed near the operating section 9a.
5 via a pressure hose 26. The water level detector 25 detects a change in the water level in the outer tank 2 as a pressure change inside the near trap 24, moves a magnetic body within the coil in accordance with this pressure change, and as a result changes the water level by changing the inductance of the coil. It is detected as a change.

A drain port 71 having a drain port (not shown) for draining water in the outer tank 2 is provided at the bottom of the outer tank 2. A drainage hose 72 is connected to lead the water out of the machine. The overflow chamber 23 is connected to the drain hose 72 via an overflow hose 230, and overflow water flowing into the overflow chamber 23 is led out of the machine through the drain hose 72. A drain electric valve 73 for opening and closing the drain port of the drain port portion 71 is provided between the drain port portion 71 and the drain hose 72, and as is well known, this is disposed below the outer tank 2. The valve is opened by winding the wire using the rotational force of the drainage motor 79, and on the other hand, by cutting off the rotational force, the valve returns to the closed state by the biasing force of a spring (not shown).

Furthermore, a dual water supply solenoid valve 8 is disposed within the housing portion 9b. The water supply solenoid valve 8 includes a first water supply hose 26 whose one end is connected to the side wall of the upper part 2a of the outer tank 2, and a second water supply hose (not shown) whose one end is connected to the front wall of the upper part 2a of the outer tank 2. ) is connected. Water discharged from the water supply electromagnetic valve 8 is supplied into the outer tank 2 via the first water supply hose 26 and the second water supply hose, and reaches the drain port 71 along the inner wall of the outer tank 2.

FIG. 3 is a vertical cross-sectional view of the inside of the drum 3 of the washing machine according to the present invention, viewed from the front, and FIG. 4 is a vertical cross-sectional view of the inside of the drum 3, viewed from the side.

The drum 3 includes a cylindrical body 31 with a horizontal axis and a bottom, and a fluid fluid balancer 32 mounted on the open side of the body 31.
It is comprised of a front plate 33 fixed to the outside of the fluid balancer 32, and is arranged in the outer tub 2 with the front plate 33 facing the front of the washing machine. At the center of the front plate 33, a suction port 34 is formed to protrude and form an axial fan that also serves as a filter for sucking in dry air.

One end of a support shaft 35, which serves as a rotation axis on the front side of the drum 3, is fixed to the center of the suction port 34, while the end of the body 31 on the opposite side to which the front plate 33 is fixed is fixed. One end portion of a support shaft 36, which is provided on the same axis as the support shaft 35 and serves as the other rotating shaft of the drum 3, is fixed to the center portion. The other end of the support shaft 35 is supported by a front bearing 350 disposed at the center of the heater casing 40, and the other end of the support shaft 36 is supported at the center of the rear wall of the outer tank 2. The drum 3 is supported by a rear bearing 360 disposed in the rear bearing 360, and the drum 3 is rotatable and rotatable around the support shafts 35 and 36.

A baffle 31 a having a triangular cross section is formed on the inner circumferential surface of the body 31 of the drum 3 and bulges toward the axis of the body 31 .
+ 31 b + 31 c are arranged at three equal intervals, and these bathofuls 31a, 31b, and 31c are adapted to scoop up laundry such as clothes in the tram 3 when the drum 3 rotates. In addition, horizontal ribs 3 extending in the axial direction of the drum 3 are provided on the inner circumferential surface and outer circumferential surface of the body portion 31 of the drum 3.
01,301. ... are formed in large numbers protrudingly. A large number of through holes 302, 302, . Water is supplied and discharged to and from the drum 3 through...

Further, on the outer periphery of the body portion 31, a central angle 12 in the body portion 31 is provided.
Recess 3 formed by reducing the diameter of the 0 degree arc part
In front of the recess 31d, a lower clothing input port 10c having a planar shape that occupies approximately 1/2 of the bottom area of the recess 31d is provided in the garden area of the recess 31d. Slide grooves 390, 390 extending in the circumferential direction are provided on the edges and the rear edge to slidably attach a synthetic resin lid 38 for opening and closing the lower clothes input port 10c. The slide grooves 390, 390 are provided with a band-shaped slide cover 3 on each of the protrusions 39L391 provided in the circumferential direction of the body 31.
92,392 is attached. The lid body 38 is
Supported within the slide groove 390.390, the slide groove 3
90. By sliding inside the 390, the lower clothing input port 1
It is designed to open and close 0c. The lid 38 is located between one side edge of the lid 38 and the mouth edge of the lower clothing input port 10c.
A locking/disengaging mechanism 37 is provided for locking and releasing the lid body 38 when the lower clothing input port 10c is closed. Further, a storage section 380 for storing laundry treatment agents such as detergent, bleach, and fabric softener is pre-concavely provided in the center of the upper surface of the lid 38 .

As mentioned above, the drum 3 is supported by the front bearing 350 and the rear bearing 360 with the support shaft 35 and the support shaft 36, but the shaft end of the rear bearing 360 protrudes outward from the rear wall of the outer tank 2. A drive boob 1774 is attached to the end of this shaft. Furthermore, a Sanwa-type motor 75 that is a power source for the drum 3 is disposed outside the bottom surface of the outer tank 2, and the drive shaft of this motor 75 and the drive pulley 74 are connected via a belt 76. connected. The drive pulley 7
A magnet 77 is attached to the outer tank 2 side of 4.
A reed switch 78 is disposed on the outer surface of the rear wall at a position facing the magnet 77. As the drive pulley 74 rotates, this reed switch 78 closes when the magnet 77 approaches and separates. It is designed to be opened when it is opened. That is, if the reed switch 78 opens and closes once,
This means that drum 3 has rotated once.

Further, a drum temperature detector 43 made of a thermistor is attached to one of the mounting fittings 4L4L41 to detect the temperature of the drum 3 by detecting the temperature of the mounting fitting 41. Further, a water boiling heater 27 with a heating element attached parallel to the bottom surface of the outer tank 2 is fixed in the outer tank 2 by a water boiling heater mounting bracket 27C, and the water boiling heater 27 can be used to heat water. It is used when washing clothes, and the water in the outer tub 2 is heated. A water temperature detector 28 is attached to the water boiling heater mounting bracket 270 to detect the water temperature in the outer tank 2 by detecting the temperature of the water boiling heater mounting bracket 270.

FIG. 5 is a plan view of the keyboard of the operating section 9a.

In the figure, reference numeral 117 indicates a reservation key group consisting of a plurality of keys that are operated to make a reservation for starting the operation at a predetermined time. A display screen 118 is provided that displays errors in input information and malfunctions in control during operation as error messages.

Further, on the right side of the reservation key group 117, there is a water temperature setting key 111a for setting the water temperature in the outer tank 2 (water temperature value, 35°C, 945°C), and a washing process time (5 minutes, 10 minutes, 15 minutes).
Washing time setting key 111b to set the number of rinses (2
Rinse number setting key 111 for setting (times, 3 times, 5 times)
c. Dehydration power setting key 1 to set the dehydration power (strong, medium 5 weak)
11d, and the output of the drying heater 4 (strong.

A row of heater output setting keys 111e are provided to set the level (lower than 2nd grade). A washing course setting key 113a for setting a washing course (standard, wool, etc.) according to the type of laundry, etc. and a drying finish state are located at a position a suitable distance away from the heater output setting key 111e to the right. Drying course setting keys 113b for setting the drying course are arranged in a row.

In addition, the water temperature setting key 111a and the washing time setting key 1
Information selected by these keys is lit behind each of the following keys: llb, rinse count setting key 111c, dehydration power setting key 1lld, heater output setting key 111e, washing course setting key 113a, and drying course setting key 113b. A water temperature setting display LED group 112a and a washing time setting display LED group 112 consisting of a plurality of LEDs to display.
b Rinse number setting display LED group 112c, dehydration power setting display LED group 112d, heater output setting display LED group 112e, washing course setting display LED group 114a, and drying course setting display LED group 114b are provided, respectively.

The water temperature setting key 111a, the washing time setting key 11
1b, rinse number setting key 111c, dehydration power setting key 1
11d, the settings of each of the heater output setting key 111e, washing course setting key 113a, and drying course setting key 113b can be changed each time they are operated, and the settings of each LED group can be changed accordingly. The lighting display is changed. In particular, when the water temperature setting key 111a, washing time setting key 111b, rinsing frequency setting key 111c, dehydration power setting key 111d, and heater output setting key 111e are operated a predetermined number of times, execution of each process can be omitted.

Further, on the right side of the drying course setting display group LED 114b is a favorite course start key 115a which is a key for starting a washing course according to the user's preference.

A standard course start key 115b, which is a key to start a predetermined standard washing course, a stop key 115c, which stops the operation of the washing machine, and a lid open key 115d, which opens the top lid 14, are arranged in a row.

In front of each of these keys is a favorite course start key acceptance display LED 116a that lights up to indicate that operation of these keys can be accepted.

Standard course start key acceptance indication LED 116b
.

A stop key acceptance indication LED 116c and a lid open key acceptance indication LED 116d are provided, respectively.

These favorite course start key 115a, standard course start key 115b, stop key 115c, and lid open key 115d each have a corresponding acceptance display L.
Key operations are enabled only when the ED is lit.

By operating these keys, the user can drive the vehicle according to his/her preference. For example, when performing a predetermined standard operation, operate the standard course start key 115b to start the operation,
When performing other operations, set the desired washing course by operating the various keys as described above, and start the operation by operating the desired course start key 115a.

Next, the configuration of the control system of the washing machine according to the present invention will be explained. FIG. 6 is a schematic block diagram showing the configuration of the control system of the washing machine.

In the figure, 100 is a first microcomputer that mainly controls the washing machine, and 200 is a second microcomputer that mainly controls the motor 75. These first microcomputer 100 and second microcomputer 200 are connected by a communication line, and can communicate information between them via this communication line.

The first microcomputer 100 includes an input key circuit 1o1, the water level detector 25. The drum temperature detector 43. Said water temperature detector 28. Signals are input from an abnormal vibration detection switch 102 that detects abnormal vibrations exceeding a predetermined value and a top cover switch 103 that opens and closes in conjunction with the opening and closing of the top 114.

The first microcomputer 100 is connected to a first drive circuit 105 and a second drive circuit 107, each of which is a circuit that drives a plurality of devices. A control signal for driving the equipment is provided. Further, the first microcomputer 100 is connected to an LED display circuit 104 made up of each LED as described above, and the first microcomputer 100 sends setting information of the washing course and the operating status of the washing machine to the LED display circuit 104. Information, etc., for LED display is given. The first drive circuit 105 includes a power-off AC solenoid 106. A drainage motor 79 and a blower fan 22 are connected, and respective drive signals are given to these from the first drive circuit 105. Said second
The drive circuit 107 includes a water supply solenoid valve 8 and an auxiliary agent injection valve 108 for introducing an auxiliary agent such as a softener into the outer tank 2. Top lid lock release solenoid 109 for unlocking the top lid 14. A water boiling heater 27 and a drying heater 4 are connected,
Respective drive signals are applied to these from the second drive circuit 107.

An inverter drive circuit 110 that drives the motor 75 using an inverter and a reed switch 78 are connected to the second microcomputer 200 . A signal regarding the rotation of the drum 3 is given to the second microcomputer 200 from the beam 78. A control signal for controlling the rotation of the motor 75 is given from the second microcomputer 200 to the inverter drive circuit 110. Further, the inverter drive circuit 110 is provided with a drive signal for forward/reverse rotation control and rotation speed control to the motor 75 connected thereto based on the control signal given from the second microcomputer 200.

The first microcomputer 100 has a first power supply circuit 11.
1 is supplied with power for its operation, and in addition to the power supply line, there is a connection between the first power supply circuit 111 and the first microcomputer 100 that is connected to the first microcomputer 100 when the power is turned on. The reset circuit 113 that performs initialization and the frequency of the power supplied from the first power supply circuit 111 are determined to be 501 (Z, 60Hz),
A frequency synchronization circuit 11 for causing the first microcomputer 100 to perform an operation synchronized with the frequency determined as a result of the determination.
5 are connected in parallel.

Further, the second microcomputer 200 is supplied with power for its operation from the second power supply circuit 112.
In addition, a second power supply circuit 112 is provided separately from the power supply line.
A reset circuit 114 that initializes the second microcomputer 200 when the power is turned on is connected between the second microcomputer 200 and the second microcomputer 200 .

The first drive circuit 105 and the device driven thereby, the second drive circuit 107 and the device driven thereby, the inverter drive circuit 110 and the motor 75 driven thereby. First power supply circuit 111 Second power supply circuit 1
12 is supplied with power from an AC power source 300. A power supply switch 1 is included in the power supply path from this AC power supply 300.
16 is provided, and when this power switch 116 is turned on, power is supplied to the control system as described above,
The washing machine is now ready for operation.

In a washing machine configured as described above, a washing course consisting of a washing process, a rinsing process, a spin-drying process, and a drying process is normally executed sequentially under the control of the first microcomputer 100 and the second microcomputer 200. On the other hand, it is also possible to perform each step selectively.
The structure is as follows: first rinsing operation, second intermediate dehydration operation, second rinsing operation, etc., and the rinsing operation and the intermediate dehydration operation performed before the rinsing operation are repeated multiple times.

Such a washing machine is operated by performing operations as described below.

After turning on the power, when the standard course start key 115b is operated (pressed) on the keyboard 111, each L
Information about the standard washing course (standard setting information such as setting time and number of operations for each step) is displayed on the ED, and operation of the standard washing course is started. In addition, when performing an operation other than the standard washing cycle, first press the water temperature setting key 11.
1a, select the process to be executed by operating the washing time setting key 111b, the number of rinse setting key 111c, the dehydration power setting key 111d, the heater output setting key 111e, the washing course setting key 113a, and the drying course setting key 113b, and select it. Set the set time and number of operations for the process. And your favorite course start key 115a
If you press , only the selected steps will be executed sequentially.

When the operation is started, in the washing process, first, water is supplied into the outer tank 2 up to the set water level, and at the same time, power is supplied to the water heater 27, and the washing water is heated up to the set water temperature set by operating the water temperature setting key 111a. heat up. During this heating operation, the operating cycle of the motor 75 is changed according to the water temperature in the outer tank 2, and the motor 7
5 is rotated back and forth to control the strength of the water flow. As a result, the drum 3 rotates back and forth to generate a weak water flow inside the outer tank 2,
To efficiently raise water temperature by stirring washing water. In addition,
The intensity of the water flow as described above can be controlled based on the relationship between the operating time of the reciprocating rotation of the drum 3 and its rest time. For example, as the ratio of the operating time to the rest time increases, the water flow intensity increases.

Next, the motor 75 is repeatedly rotated back and forth within a set time with an operation cycle of, for example, 9 seconds on and 3 seconds off. As a result, the drum 3 rotates back and forth, and inside the drum 3, the laundry is transferred to the baffle 3.
So-called slapping washing is performed in which the washing is swept up by 1a, 31b, and 31c and then falls down. Further, at the same time as the motor 75 is turned off as described above, DC braking is applied to the motor 75 for, for example, 2 seconds. As a result, the drum 3 suddenly stops, and the laundry is washed against the inner wall of the drum 3 by the reaction.

Further, in the rinsing operation during the rinsing process, the motor 75 is controlled in the same way as in the washing process, and rinsing is performed.

In the intermediate dehydration operation and dehydration step during the rinsing step,
A drum 3 for dehydration whose water level in the outer tank 2 is set in advance
When the reset water level reaches a low set water level that allows rotation of the motor 75, the motor 75 is rotated in one direction at high speed. As a result, the laundry in the drum 3 is dehydrated by centrifugal force.

In the drying process, the motor 75 is rotated in one direction, the drying heater 4 is energized, and hot air is sent into the drum 3 by the blower fan 22 and the axial fan, and the laundry in the tram 3 is or dried.

Next, a method of controlling water flow during a water boiling operation in a washing process in a washing machine configured as described above will be described. FIG. 7 is a flowchart showing the procedure for water flow control during water boiling operation.

First, the first microcomputer 100 determines whether or not the water boiling operation is in progress by checking the power supply state to the water boiling heater 27 (step 1).

If it is determined in step 1 that water heating is in progress, the water temperature set value is read from the input key circuit 101, and the water temperature detection take is read from the water temperature detector 28 (step 2), and the water temperature is detected from the water temperature set value. Calculate the water temperature deviation ΔT by subtracting the data (Step 3)
.

Next, it is determined whether the calculated water temperature deviation ΔT is 0°C or not (step 4), and if it is determined that the water temperature deviation ΔT is 0°C, the electricity to the water heater 27 is cut off, The water boiling operation is ended (step 12).

On the other hand, if it is determined in step 4 that the water temperature deviation ΔT is not 0° C., it is determined whether the water temperature deviation ΔT is 15° C. or more (step 5).

If it is determined in step 5 that the water temperature deviation ΔT is 15° C. or more, the drum 3 is reciprocated with an operation cycle of 1 second on and 10 seconds off (step 8), and the process returns to step 1.

On the other hand, if it is determined in step 4 that the water temperature deviation ΔT is not 15° C. or higher, it is determined whether the water temperature deviation ΔT is 10° C. or higher (step 6).

If it is determined that the water temperature deviation ΔT is 10° C. or higher in the ST and PRO, the drum 3 is reciprocated with an operation cycle of 2 seconds on and 6 seconds off (step 9), and the process returns to step 1.

On the other hand, if it is determined in step 6 that the water temperature deviation ΔT is not 10° C. or more, it is determined whether the water temperature deviation ΔT is 5° C. or more (step 7).

If it is determined in step 7 that the water temperature deviation ΔT is 5° C. or higher, the drum 3 is reciprocated with an operation cycle of 3 seconds on and 5 seconds off (step 10), and the process returns to step 1.

On the other hand, if it is determined in step 7 that the water temperature deviation ΔT is not 5° C. or higher, the drum 3 is reciprocated with an operation cycle of 3 seconds on and 3 seconds off (step 11), and the process returns to step 1.

Such control of the operation cycle of the drum 3 is repeated until the water temperature deviation ΔT reaches 0°C. Then, when the water temperature deviation ΔT reaches 0° C., the water flow is switched to a strong water flow, and the washing operation is performed using this strong water flow.

In the above control, the strength of the weak water flow generated during a rise in water temperature is increased in accordance with the rise in water temperature in the outer tank 2. Therefore, when the water temperature deviation ΔT is large, that is, the water temperature is If it is low, the water flow will slowly stir the water in the outer tank 2.

In addition, as the water temperature deviation ΔT decreases, that is, as the outside temperature approaches the water temperature set value, the strength of the water flow increases, so the water in the outer tank 2 is sufficiently agitated, and the outside temperature can be detected with high accuracy. The rate of increase is also fast.

Effect C] As detailed above, in the washing machine according to the present invention, a weak water flow is generated until the water temperature in the outer tub reaches a predetermined temperature. It is weak and does not cause unnecessary damage to the laundry, making it possible to sufficiently suppress damage to the laundry.Furthermore, as the water temperature rises, the water flow is strengthened, increasing the stirring power of the water in the tank. As the temperature increases, the difference in water temperature at each location in the water tank until the predetermined temperature is reached becomes smaller, making it possible to increase the rate of increase in water temperature. The present invention has excellent effects such as further improvement in the rate of increase in water temperature.

[Brief explanation of the drawing]

FIG. 1 is a loading perspective view of a washing machine according to the present invention, FIG. 2 is a vertical cross-sectional view of the outside of the outer tub viewed from the front, FIG. 3 is a vertical cross-sectional view of the inside of the drum viewed from the front, and FIG. Figure 4 is a longitudinal sectional view of the inside of the drum viewed from the side, Figure 5 is a plan view of the keypad of the operation section, Figure 6 is a schematic diagram showing the configuration of the control system of the washing machine, and Figure 7 1 is a flowchart showing a procedure for water flow control during a water boiling operation. 2...Outer tank 28...Water temperature detector 100...
・First microcomputer 200...Second microcomputer

Claims (1)

[Claims] 1. A weak water flow is generated in the water tank while heating the water in the water tank, and when the water temperature reaches a predetermined temperature, the water flow in the water tank is switched to a strong water flow. a washing machine comprising: a means for detecting the water temperature in the water tank; a means for comparing the detection result of the means with the predetermined temperature; and means for controlling the strength of the weak water flow.