JPH03202097A - Dry control method for drum type wash drier - Google Patents

Abstract

PURPOSE:To efficiently perform drying by repeating a fast operation to increase the rotating speed of a drum to the one where the weight of washing and a centrifugal force keep balance in the neighborhood of the inner peripheral plane of the drum and a slow operation to perform the tumbling rotation of the drum alternately. CONSTITUTION:When the rotating speed of the drum 23 is increased to marginal speed N where the centrifugal force applied to the washing and the weight keep balance, the washing is distributed uniformly in the inner plane of the drum 23, and ventilation resistance can be uniformalized, therefore, all the washing can be heated and dried uniformly. At such a case, since the washing almost ceases when the drum is operated at the marginal speed and no alternation occurs, a uniform and efficient operation can be performed by rotating the drum at the marginal speed and the slow tumbling speed alternately. Thereby, it is possible to efficiently perform the drying in spite of the volume of the washing and the deviation of the washing in the inside of the drum. Also, since the relative motion of the washing for the drum is scarcely performed with the operation at the marginal rotating speed, the damage on cloth of the washing can be reduced.

Description

Detailed Description of the Invention (a) Industrial Application Field The present invention relates to a drum-type washer/dryer that performs everything from washing to drying in one drum, and more specifically, to improve its drying efficiency and prevent uneven drying. This invention relates to improvements in control methods for

(b) Conventional technology In general, drum-type washer/dryers have a structure in which the drum rotates around a horizontal axis, and since washing and drying can be done in the same drum, the washing function, dewatering function, and drying function This is a typical washer/dryer with multiple functions.

Also, after loading the laundry (clothes to be washed and dried),
It has the possibility of fully automatic laundry that does not involve any acquisition until the drying is completed.

Hereinafter, the structure and operation of the conventional drum-type washer/dryer will be explained according to the schematic diagram of the conventional drum-type washer/dryer shown in FIG.

The drum-type washer/dryer has a water tank 2 suspended from an outer box I by a spring 4, a drum 3 arranged to rotate around a horizontal axis inside this water tank 2, and a double drum 3 and a double +R drum. It's crawling. Water F! 2 is suspended by a spring 4 to absorb vibrations during operation, and this has the function of storing and discharging the washing layer and dehydrating material. The drum 3 has a large number of small holes 5 on its entire peripheral wall through which water is supplied during washing, drainage during dehydration, and hot drying air is passed during drying. In addition, on the inner surface of the peripheral wall of the drum 3, there is a baffle (
A plurality of protrusions) 6 are provided.

The most important step is to put the laundry into the drum 3 through the opening 8,
This is carried out by dripping washing water in which the preparation has been dissolved from above to soak it in the laundry, and rotating the drum 3 at a low speed. The laundry in the drum 3 is lifted near the top of the drum 3 by the centrifugal force caused by the rotation of the drum 3 and the baffle 6, and then falls due to its own weight (referred to as "tumbling").

This tumbling is repeated, and the laundry is washed by the impact force when it falls. Rinsing is done in the same way.

The dehydration work is done by rotating the drum 3 at high speed and using its centrifugal force. This is done by pressing the Ic laundry against the inner surface of the peripheral wall of the drum 3. Water is blown out from the small hole 5 of the drum 3,
The switching valve 7 is guided along the inner surface of the water tank 2 to its lower part
It is then ejected from the aircraft.

The drying work is performed by rotating the drum 3 at a low speed while blowing drying hot air through the opening 8 R of the drum 3. In addition,
Since laundry increases in bulk as it dries, the maximum amount that can be dried at one time is about half of the amount washed. This is because, in order to eliminate uneven drying, it is necessary to rotate the drum 3 at a low speed and change the position of the laundry by tumbling.

In FIG. 4, 13 is a drive motor that rotates the drum 3, and 15 is a circulation pump that circulates washing water.

(c) Problems to be solved by the invention When drying with such a conventional drum-type washer/dryer,
The hot air for drying enters from the drum 3 (111 side) and is discharged from the small hole 5 on the circumference.At this time, the hot air resistance changes depending on the area where there is laundry and the area where there is no laundry, so the hot air flows in the direction where there is no cloth. It becomes easy to flow, comes into contact with laundry, and is likely to be discharged, reducing drying efficiency.

This tendency is noticeable when the amount of laundry is small or when the fabric is bulky just after it has been dehydrated. Moreover, when the amount of laundry is large, uneven drying is likely to occur.

On the other hand, if the drum 3 is rotated at high speed during dewatering, the centrifugal force will force the laundry 9c against the inner surface of the peripheral wall of the drum 3.
Ru. The pressed laundry gets stuck in the many small holes 5. This biting and sticking of the laundry does not allow it to fall naturally to the drum 3. Therefore, there was a problem in that the operation had to be stopped once after the spin-drying was completed, and the laundry had to be shaken by hand before starting the drying operation.

This invention was made in consideration of these circumstances,
The present invention provides a drying control method that allows efficient drying by appropriately changing the drum rotation speed.

(d) Means for Solving the Problems This invention comprises a water tank fixed in a main body case, a drum rotatably supported in the tank and having a large number of water passage/ventilation holes on the peripheral wall, and a water tank fixed in a main body case. A two-chamber air circulation path is installed, a heat exchanger installed in the circulation path to dehumidify the exhaust air from the drum, and a heating blower installed in the circulation path to heat the dehumidified air and supply it to the drum. Equipped with f codrum type G,
A drying control method for a washer/dryer includes a high-speed operation in which the drum is rotated at a speed at which the gravitational force and centrifugal force acting on the laundry are balanced with each other, and a low-speed operation in which the drum is rotated at a speed at which the laundry tumbles within the drum. This is a drying control method for a drum-type washing/drying bin, which is characterized in that drying is performed alternately. In addition, the present invention compares the air temperature immediately before being dehumidified by the heat exchanger and the air temperature immediately after dehumidifying, and when the difference between them becomes a predetermined value or more during low-speed operation, high-speed operation is performed. This is a drying control method for a dryer.

(e) Effect When drying is performed with tumbling rotation (low speed operation), the laundry is lifted to near the top of the drum and then falls under its own weight. At this time, if the amount of laundry is small, the hot air tends to flow through the small holes in the parts not covered by the laundry, reducing efficiency. Also, if the amount is too large, it will be difficult to wash the laundry and cause uneven drying.

Therefore, if the rotational speed of the drum is increased to a rotational speed at which the weight of the laundry and the centrifugal force are balanced near the inner surface of the drum (high-speed operation), the laundry will be distributed almost uniformly on the inner surface of the drum and will come into contact with the drum lightly. Because they rotate in synchronization, the north flow of warm air is dispersed, allowing for efficient drying. In addition, since the centrifugal force of the cloth is small, it moves slowly and as a result, the laundry is evenly distributed on the inner surface of the drum. By repeating high-speed and low-speed operation alternately in this way, the laundry can be changed frequently and drying can be done evenly and efficiently.

However, if the cloth partially clumps during drying by tumbling rotation, the temperature difference between the entrance and exit of the heat exchanger in the hot air circulation path will increase. Therefore, by detecting this temperature difference and switching from low-speed operation to high-speed operation when the temperature reaches a certain level, the ratio of the period of low-speed operation to the period of high-speed operation can be appropriately determined.

(f) Examples Hereinafter, the present invention will be described in detail based on examples shown in the drawings. This invention is not limited thereby.

FIG. 1 is an explanatory diagram of the configuration of a drum-type washer/dryer showing an embodiment of the present invention. It has 22.

This water tli 122 is suspended from the case 21 by a spring 24, so that vibrations generated during washing and dehydration are absorbed. The drum 23 has small holes 23a around its entire circumference for drainage and dry air circulation, and the water tank 22
Rotatably provided inside.

Also, near the side wall inside the drum 23, a washing protrusion 27 is provided.
A stirring plate 27 having a plurality of 2Ls is installed coaxially with the drum 23 and rotatable independently. Aquarium 2
A switching valve 25 for discharging washing liquid after washing, a circulation pump 26 for circulating washing water, and motors 28 and 29 for driving the drum 23 and stirring plate 27 are attached to the bottom of the washing machine 2. There is. In order to make the rotational direction (reverse rotation, synchronization) and rotational speed of the drum 23 and stirring plate 27 variable independently of each other, the motors 28 and 29 may each be a DC motor, but a DC brushless motor may be used. A combination of may also be used.

On the other hand 1. In order to circulate hot air when drying the laundry, a hot air outlet 30 is provided on the side wall of the drum, and a hot air outlet 31 is provided on the side wall of the water tank 22. As shown in FIG. 3, the hot air circulation system connects a hot air outlet 30 and a hot air outlet 31 with a duct 32, and the duct 32 includes a blower fan 33, a dehumidifying heat exchanger 34, and an air boosting heater 35.
is installed.

Next, an outline of the operating operations from washing to drying will be explained.

Washing is carried out by putting the washing liquid in the water tank 22 and the laundry in the drum 23, and then rotating the drum 23 and stirring plate 27 periodically or in reverse rotation. For rinsing, change the washing water in the same way. Dehydration: After rinsing is completed, the rinsing water is discharged by opening the switching valve 25, and then the drum 23 and stirring plate 27 are synchronously rotated at high speed (500 to 1000 rpm) using centrifugal force.

Drying is carried out by circulating warm air inside the drum 23 with a blower fan 33 while rotating the drum 23 and the rX stirring plate 27 synchronously at low speed. That is, from the hot air outlet 30 to the drum 23
The air introduced into the laundry heats the laundry, evaporates moisture, and is discharged from the hot air outlet 31 in a highly humid state. Thereafter, it is cooled and dehumidified by a dehumidifying heat exchanger 34, heated again by a heater 35, and guided into the drum 23 in a high temperature and low humidity state. Repeat this process to dry. In this drying process,
Dry air enters from a warm air outlet 30 near the center of the side wall of the drum 23, is discharged out of the drum 23 in fractions through small holes 3a on the circumference, and is collectively discharged from an outlet 31 on the side of the water FW 22. At this time, when the amount of laundry is small, as shown in FIG. 2(b), when the laundry rotates at a tumbling rotation speed (low speed), it is partially biased in the drum 23, causing air to flow. The drying efficiency tends to be concentrated in the easier small holes 3a (that is, those that are not blocked by laundry), resulting in a decrease in drying efficiency.

Therefore, if we set the rotational speed of the drum 23 to the critical speed at which centrifugal force and gravity acting on the laundry are balanced, then the laundry: The airflow resistance is evenly distributed, and all the laundry is evenly heated and dried.

Note that this critical speed N (rpm) is calculated by the following formula.

N=30. ;2g/π2d However, g: gravitational acceleration (cm/5ec2), d Ni drum inner diameter (cm) Therefore, for example, when d=60cm, N=54゜6
rpm. In this case, if the laundry is operated only at the critical speed, the laundry will be almost stationary and will not be replaced, so by alternating with the operation at the tumbling speed, uniform and efficient operation can be achieved. This alternating operation may be switched at intervals of a certain period of time, but if the temperature of the dehumidifying heat exchanger 34 and the outlet temperature are detected and the temperature difference is above a predetermined value, that is, the laundry in the drum 23 is If the drying becomes uneven and sufficient dehumidification is not performed, the rotation speed can be controlled to be increased. In addition, if operation is performed at critical speed after a certain period of time has elapsed after starting dewatering operation, water tli22
, the time required to raise the temperature of the drum 23 and the pre-washed laundry to the drying temperature can be shortened. (Well, since the laundry is stuck to the entire inner peripheral surface of the drum 23,
This is because the hot drying air is wasted and used to heat the laundry.

(G) Effects of the Invention According to the present invention, uniform and efficient drying can be performed regardless of the amount of laundry or the unevenness of the laundry inside the drum during operation. In addition, in the operation at the critical rotation speed, the laundry hardly moves relative to the drum, so the damage to the laundry is reduced.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the configuration of a drum type washer/dryer showing an embodiment of the present invention, FIGS. 2(a) and 2(b) are explanatory diagrams showing the state of laundry in the drum, FIG. 3 is a block diagram showing the circulation path of drying air in the embodiment shown in FIG. 1, and FIG. 4 is an explanatory diagram of the configuration of a conventional drum two-tiger dryer. 21...Outer box, 22...Mizuhiro, 23...Drum, 23a...Small hole, 25...Switching valve, 27...-Stirring board, 2829...For driving Motor, 31...Hot air outlet, 30...Hot air inlet, 35, Heater, 34...Dehumidifying heat exchanger. W! 11WI Figure 2 (a) (b) Rumen 5 3

Claims (1)

[Claims] 1. A water tank fixed within the main body case, a drum rotatably supported within the tank and having a large number of water passage/ventilation holes on the peripheral wall, and an air circulation path installed through the drum. and a heat exchanger installed in the circulation path to dehumidify the air discharged from the drum.
In a drying control method for a drum type washer/dryer equipped with a heating blower installed in a circulation path to heat dehumidified air and supply it to the drum, the drying method is performed at a speed at which gravity and centrifugal force acting on the laundry balance each other. A drying control method for a drum-type washer/dryer characterized by alternately performing high-speed operation in which the drum is rotated and low-speed operation in which the drum is rotated at a speed at which laundry tumbles within the drum. 2. The drum-type washer/dryer according to claim 1, wherein the air temperature immediately before being dehumidified by the heat exchanger and the air temperature immediately after dehumidification are compared, and when the difference between them becomes a predetermined value or more during low-speed operation, high-speed operation is performed. Drying control method.