JPH0663292A - Drum type washing machine - Google Patents

Abstract

PURPOSE:To provide a drum type washing machine capable of making the vibration transmitted to the floor minimum by setting the necessary minimum buffer capability of the buffer body at the time of the vibration of a water tank, particularly the resonance rotation by spin-drying. CONSTITUTION:A drum washing machine comprises a drum 15 provided with holes for drainage on the external periphery that rotates on the horizontal axis, a water tank 14 incorporating a drum and containing washing water, a spring body 20 for hanging a water tank from the body. There are provided plural buffer bodies 21 that inhibit the vibration of the water tank and that can adjust the buffer capabilities, a vibration detection means 25 for detecting the width of vibration and a control means 24 for controlling the buffer capability of the buffer body by setting the output of the vibration detection means to an input.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drum type washing machine for washing and centrifugally dehydrating laundry with a drum which is rotationally driven about a horizontal axis, and particularly to reduce vibration during dehydration. .

[0002]

2. Description of the Related Art A conventional drum type washing machine has a structure as shown in FIG. In the figure, reference numeral 1 is a drum that rotates around a horizontal axis, and a large number of water passage holes 2 are provided in the outer peripheral portion.
3 is a water tank which contains the drum 1 and stores the washing water. 4 is a motor for driving the drum 1, 5 is a horizontal shaft having one end fixed to the center of rotation of the drum 1, 6 is a drum pulley provided at the other end of the horizontal shaft 5, and 7 is a belt connecting the motor 4 and the drum pulley 6. is there. Reference numeral 8 is a spring body for suspending the water tank 3 from the main body 9, 10 is a buffer body for damping the vibration of the water tank 3, and 11 is a weight provided in the water tank 3 for reducing the vibration at the time of dehydration.

In the above structure, during the washing process, the drum 1 is driven to rotate at a low speed by the motor 4, and the laundry in the drum 1 is lifted and dropped onto the water surface for washing. The same process as the washing process is performed during the rinsing process. During the dehydration process, the clothes are dehydrated by rotating the drum 1 at a high speed.
At this time, when the clothes in the drum 1 are offset, that is, unbalanced, the drum 1 and the water tank 3 vibrate. Particularly, the large vibration caused by the resonance at the time of starting the dehydration is reduced by using the buffer body 10 having an extremely large buffering force.

[0004]

The conventional drum type washing machine described above has the following problems. That is, it is a problem of vibration of the water tank 3 caused by uneven distribution of the clothes in the drum 1 during dehydration. In particular, due to resonance at the time of dehydration startup,
The water tank 3 vibrates very greatly. The conventional buffer 10 is
Aquarium 3 against the maximum possible imbalance in clothing
In order to prevent a large vibration of the above and suppress it to a predetermined vibration amount or less, a very large buffering force is provided. Therefore, the vibration of the water tub 3 is very easily transmitted to the main body 9 via the buffer 10, and further, the large vibration is transmitted to the floor surface where the washing machine is installed. As a result, the floor surface vibrates significantly, and in a wooden house, the entire house may vibrate, which gives the user an unpleasant feeling. In addition, there is a big problem in terms of noise.

Therefore, the present invention provides a drum type washing machine in which the vibration of the water tank during dehydration, particularly the minimum necessary cushioning capacity of the buffer during resonance rotation, is set to minimize the vibration transmitted to the floor surface. Is the primary purpose.

Further, there is provided a drum type washing machine in which the vibration of the water tank during dehydration, particularly the minimum necessary cushioning capacity of the buffer during resonance rotation from the start of dehydration, is set to minimize the vibration transmitted to the floor surface. The second purpose is to do.

Further, when adjusting the buffer capacity of the buffer body to reduce the vibration of the water tank at the time of dehydration, the rapid vibration of the water tank caused by the change of the buffer capacity is minimized and transmitted to the floor surface at the time of adjustment. A third object is to provide a drum type washing machine that can minimize vibration.

[0008]

[Means for Solving the Problems] A first means of the present invention for achieving the first object is to provide a drum having a water passage hole on its outer periphery and rotating around a horizontal axis, and a washing water containing the drum. A water tank for accumulating, a spring body for suspending the water tank from the main body, a plurality of buffer bodies for suppressing vibration of the water tank and adjusting a cushioning capacity, a vibration detecting means for detecting an amplitude of vibration of the water tank, and the vibration detecting The output of the vibration detecting means is used as an input, the buffering capacity of all of the plurality of buffers is increased at the start of dehydration, and the output of the vibration detecting means is reached when the drum reaches a first predetermined rotational speed equal to or lower than the resonance rotational speed. Is smaller than a predetermined value, the buffering capacity of the part of the buffer bodies is reduced, and when the output is larger than a predetermined value, the buffering capacity of all the buffer bodies is maintained high, and the drum resonates. When the second predetermined number of revolutions above the number of revolutions is reached, all of the above It is an a control means for controlling reducing the buffering capacity of the buffer drum type washing machine.

The second means of the present invention for achieving the second object is to provide a drum having a water passage hole on its outer periphery and rotating about a horizontal axis, a water tank containing the drum and storing washing water, A spring body that suspends the water tank from the main body, a plurality of buffer bodies that can suppress the vibration of the water tank and adjust the buffering capacity, a vibration detection unit that detects the amplitude of the vibration of the water tank, and the output of the vibration detection unit is input. At the start of dehydration, the buffer capacity of some of the plurality of buffers is increased, and when the drum reaches the first predetermined rotation speed below the resonance rotation speed, the output of the vibration detection means has a predetermined value. When it is larger, the buffering capacity of all the buffers is increased, and when the output is smaller than a predetermined value, the buffering capacity of some of the plurality of buffers is maintained high, and the drum is maintained. When the second predetermined number of revolutions above the resonance number of revolutions is reached, It is to the drum type washing machine and a control means for controlling reducing the buffering capacity of the buffer of all.

The third means of the present invention for achieving the third object is to provide a drum having a water passage hole on its outer periphery and rotating about a horizontal axis, a water tank containing the drum and storing washing water, A spring body that suspends the water tank from the main body, a plurality of buffer bodies that suppress the vibration of the water tank and the buffer capacity can be adjusted, and at the start of dehydration, the buffer capacity of all of the plurality of buffer bodies is increased, and the drum The drum type washing machine is provided with a control means for controlling the buffering capacity of the plurality of buffers to be successively decreased at a predetermined time interval when a predetermined number of revolutions higher than the resonance number of revolutions is reached. .

[0011]

The first means of the present invention is to adjust the cushioning capacity of the cushioning body according to the number of rotations of the drum and the amount of vibration of the water tank so as to minimize the vibration transmitted to the floor surface. That is, assuming that the amount of imbalance that can occur at the start of dehydration is the maximum, the buffering capacity of all the plurality of buffers is set to be large. After that, when the drum reaches the first predetermined number of rotations, if the vibration amount of the water tank is smaller than the predetermined value, it is determined that the unbalance amount is small, and the buffering capacity of some of the buffer bodies is reduced. Further, when the amount of vibration of the water tank is larger than a predetermined value, the buffering capacity of all the buffer bodies is maintained large.
This makes it possible to minimize the vibration transmitted to the floor surface via the buffer when passing through the resonance rotation. Further, when the second predetermined number of revolutions higher than the resonance number of revolutions is reached, by reducing the buffering capacity of all the cushioning bodies, it is possible to significantly reduce the vibration transmitted to the floor surface above the resonance number of revolutions.

Further, the second means of the present invention acts as the second means for minimizing the vibration transmitted to the floor surface. That is, at the start of dehydration, the buffering capacity of some of the buffer bodies is increased and the minimum necessary buffering capacity is set, assuming the most likely imbalance amount. After that, when the drum reaches the first predetermined number of rotations and the vibration of the water tank is larger than a predetermined value, it is determined that the unbalance amount is large, and the cushioning capacity of all the cushioning bodies is made large. Further, when the vibration of the water tank is smaller than a predetermined value, the buffering capacity of some of the plurality of buffer bodies is kept high. by this,
Only when the amount of unbalance is very large, the cushioning capacity of the cushioning body can be varied to minimize the vibration transmitted to the floor surface through the cushioning body when passing through the resonance rotation. Further, when the second predetermined number of rotations is reached, by reducing the buffering capacity of all the buffers, it is possible to significantly reduce the vibration transmitted to the floor surface above the resonance rotation.

Furthermore, the third means of the present invention acts as a third means for minimizing the vibration transmitted to the floor surface. That is, assuming that the amount of imbalance that can occur at the start of dehydration is the maximum, the buffering capacity of all of the plurality of buffers is increased. After that, when the drum reaches the first predetermined number of revolutions, the cushioning capacity of the plurality of cushioning bodies is gradually reduced at predetermined time intervals, and the cushioning ability is gradually adjusted to be small. With this, it is possible to minimize the abrupt vibration of the water tank caused by the adjustment of the buffer capacity, and to minimize the vibration transmitted to the floor surface when the buffer capacity is changed. Further, when the second predetermined number of revolutions higher than the resonance number of revolutions is reached, by reducing the buffering capacity of all the cushioning bodies, it is possible to significantly reduce the vibration transmitted to the floor surface above the resonance number of revolutions.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the first means of the present invention will be described below with reference to FIGS.
It will be described with reference to FIG. Reference numeral 12 is a main body of the drum type washing machine (hereinafter, simply referred to as main body), 13 is a clothes insertion lid provided on the front surface of the main body 12 so as to be openable and closable, and 14 is a water tank containing a drum 15 rotating around a horizontal axis for storing washing water. , 15a is a water passage hole provided on the outer periphery of the drum 15, 16 is a horizontal shaft which penetrates the water tank 14 and has one end fixed to the center of rotation of the drum 15,
7 is a drum pulley provided on the other end of the horizontal shaft 16, 18 is a motor for driving the drum pulley 17, 19 is a belt connecting the motor 18 and the drum pulley 17, and 20 is a water tank 14.
Is a spring body that suspends the. Also 21a and 2
Reference numeral 1b denotes a shock absorber provided in such a manner that the water tank 14 and the main body 12 are connected to each other in order to damp the vibration, and in this embodiment, the shock absorbing ability is set to a large state or a small state. 22 is a weight for suppressing the vibration of the water tank 14, 23 is a heater for heating the washing water, and 24 is a control means for controlling the motor 18, the buffers 21a, 21b, the heater 23 and other controls. There is. Reference numeral 25 is a vibration detecting means for detecting the vibration of the water tank 14. In this embodiment, an acceleration sensor is used, and its output is inputted to the control means 24.

The detailed structure of the buffer 21 is shown in FIG. Reference numeral 26 is a cylinder having a circular cross section, 27 is a piston, and the cylinder 26 is provided on the outer peripheral portion of the piston 27.
There is provided a sliding member 28 that slides on the inner surface of the member and generates a buffering force by frictional force. Reference numeral 29 is a rod fixed to the piston 27, and a notch 30 is provided. Reference numeral 31 is a main body mounting portion, and the main body mounting portion 31 includes a metal 32 and the rod 2
9 is slidable, and solenoids 33a ・ 33
The pin 34 can be inserted into the notch 30 of the rod 29 by b. Reference numeral 35 is a bias spring, which presses the pin 34 so as to be inserted into the notch 30. Three
Reference numeral 6 is a water tank attachment portion for attaching the buffer 21 to the water tank 14.

When the shock absorber 21 is in the state shown in FIG. 4A, that is, when the solenoid 33 is not energized, the pin 3
4 is a notch 3 of the rod 29 by the bias spring 35.
It is inserted at 0. In this state, the piston 27 slides on the cylinder 26, and the buffer 21 operates as a friction damper accompanied by a frictional force generated between the cylinder 26 and the sliding member 28 of the piston 27. In addition, the buffer 21 is shown in FIG.
In the state shown in (b), that is, when the solenoid 33 is energized, the pin 34 is moved by the solenoid 33 to the rod 29.
It deviates from the notch 30 of. In this state, the piston 27 does not move, the rod 29 slides on the metal 32 of the main body mounting portion 31, and the shock absorber 21 slides with an extremely weak force.

Next, the operation of this embodiment will be described with reference to the flow chart shown in FIG. When you start washing, the aquarium 1
Water is supplied to heater 4 and heater 2
3 is energized. At this time, the drum 15 is rotationally driven at a low speed by the motor 18, and the clothes in the drum 15 are lifted and dropped onto the water surface for washing. When this washing process is completed, the washing water is drained and a rinsing process for rinsing a predetermined number of times is started. When the rinsing step is completed and the dehydration step is entered, the control means 24 acts as follows to perform vibration isolation.

In the dehydration process, the drum 15 is rotationally driven at a high speed by the motor 18, and the clothes are centrifugally dehydrated. At the start of this dehydration, assuming that the amount of imbalance that can occur is the maximum, the control means 24 sets the buffering capacity of all of the buffers 21a, 21b to a large value. That is, in this embodiment, as shown in FIG. 4A, the solenoids 33a and 33b forming the shock absorbers 21a and 21b are not energized, that is, the pin 34 is cut by the bias spring 35 to cut the rod 29. It is in a state of being inserted into the notch 30. In this way, the buffers 21a and 21b are operated as a friction damper with a large frictional force. After that, when the drum 15 reaches a first predetermined rotation speed equal to or lower than the resonance rotation speed, which is about 200 r / m in this embodiment, the output of the vibration detection means 25, that is, the vibration of the water tank 14 is detected. At this time, when the vibration of the water tank 14 is smaller than a predetermined value, it is determined that the amount of unbalance is small, and the buffering capacity of some of the buffers is reduced. That is, in this embodiment, the buffer 21a is operated as a damper having a very small buffering capacity. That is, as shown in FIG. 4B, by energizing the solenoid 33a,
The pin 34 is removed from the notch 30 of the rod 29. This makes it possible to minimize the vibration transmitted to the floor surface via the buffer 21a when passing through the resonance rotation. After that, when the drum 15 reaches a second predetermined rotational speed of about 400 r / m which is higher than the resonance rotational speed, the buffering capacity of all the buffers 21a and 21b is set to be small. In this way, it is possible to significantly reduce the vibration transmitted to the floor surface above the resonance rotation.

Further, the vibration detecting means 2 when the drum 15 reaches a first predetermined rotational speed of about 200 r / m which is lower than the resonance rotational speed.
When the detected value of 5 is larger than the predetermined value, it is determined that the amount of unbalance is large, and the buffering capacity of all the buffers is kept large. That is, in this embodiment, the buffer 21
4a is operated as a friction damper with a large frictional force. Thereby, even when the amount of unbalance is large, the vibration of the water tank 14 when passing through the resonance rotation can be minimized. After that, the drum reaches a second predetermined rotational speed 400 above the resonance rotational speed.
When it reaches r / m, the buffering capacity of all the buffer bodies 21a and 21b is set to be small. In this way, it is possible to significantly reduce the vibration transmitted to the floor surface above the resonance rotation.

In this embodiment, the first predetermined rotation speed is set to 2
Although the second predetermined rotation speed is set to 00r / m and 400r / m, there is no reason to particularly set these rotation speeds.

Next, an embodiment of the second means of the present invention will be described. The configuration of this embodiment is the same as that of the above embodiment,
The only difference is the control procedure of the control means 24. Figure 7 below
The operation of this embodiment will be described based on FIG. At the start of dehydration, the unbalance amount that is most likely to occur is assumed, and the control means 24 sets only a part of the plurality of buffer bodies to have a large buffer capacity. That is, in this embodiment, as shown in FIG.
3a is energized to reduce the buffer capacity, and the buffer body 21b operates as a friction damper with a large frictional force.

After that, when the drum 15 reaches the first predetermined rotation speed of about 200 r / m, which is lower than the resonance rotation speed, the vibration detecting means 25 detects the vibration of the water tank 14. At this time, when the vibration of the water tank 14 is larger than a predetermined value, it is determined that the amount of unbalance is large, and all the buffers 21a.
Increase the buffering capacity of 1b. Then, when the second predetermined rotation speed of about 400 r / m which is equal to or higher than the resonance rotation speed is reached, the setting is changed so as to reduce the buffering capacity of all the buffer bodies 21a and 21b. In this way, it is possible to significantly reduce the vibration transmitted to the floor surface above the resonance rotation.

Further, when the output of the vibration detecting means 25 when the drum reaches the first predetermined number of revolutions lower than the resonance number of revolutions is smaller than the predetermined value, it is judged that the unbalance amount is small, and a plurality of unbalanced amounts are obtained. The buffer capacity of some of the buffer bodies is kept high. After that, when the drum reaches the second predetermined number of revolutions higher than the resonance number of revolutions, the cushioning capacity of all the cushioning bodies is reduced.

According to this embodiment, the buffer capacity of the buffer body is adjusted only when the unbalance amount is very large.
It is possible to minimize the vibration that is transmitted to the floor surface via the buffer when passing through the resonance rotation.

Next, an embodiment of the third means of the present invention will be described. The configuration of this embodiment is the same as that of the above embodiment,
The only difference is the control procedure of the control means 24. Figure 8 below
The operation of this embodiment will be described based on FIG. At the start of dehydration, the control means 24 sets the buffering capacity of all of the plurality of buffers to be large, assuming that the amount of imbalance that can occur is maximized. That is, the buffer 21
As shown in FIG. 4 (a), the pins a, 21b are in a state in which the solenoids 33a, 33b are not energized.
Is inserted in the notch 30 of the rod 29.

After that, when the drum 15 reaches the first predetermined rotational speed of about 400 r / m which is equal to or higher than the resonance rotational speed, the buffering capacity of the plurality of buffer bodies 21a and 21b is gradually reduced at predetermined time intervals. It goes. In this way, the buffer capacity can be adjusted to be gradually smaller.

This makes it possible to minimize the abrupt vibration of the water tank 14 caused by the change in the buffer capacity, and also minimize the vibration transmitted to the floor surface when adjusting the buffer capacity. Further, when the second predetermined number of revolutions equal to or higher than the resonance number of revolutions is reached, the cushioning capacity of all the cushioning bodies can be reduced, and the vibration transmitted to the floor can be extremely reduced.

[0028]

As described above, according to the first means of the present invention, the drum having the water passage hole on the outer periphery and rotating about the horizontal axis, the water tank for accommodating the washing water and containing the drum, and the water tank from the main body are provided. A suspension spring body, a plurality of buffer bodies that can suppress the vibration of the water tank and adjust the buffer capacity, a vibration detection unit that detects the amplitude of the vibration of the water tank, and the output of the vibration detection unit as an input,
At the start of dehydration, the buffering capacity of all of the plurality of buffers is increased, and when the drum reaches a first predetermined rotational speed equal to or lower than the resonance rotational speed, the output of the vibration detecting means is smaller than a predetermined value. In some cases, the buffer capacity of some of the buffer bodies is reduced,
When the output is higher than a predetermined value, the buffering capacity of all the buffer bodies is maintained high, and when the drum reaches a second predetermined rotational speed equal to or higher than the resonance speed, the buffering capacity of all the buffer bodies is increased. As a drum type washing machine equipped with a control means for controlling the vibration to a small level, the vibration transmitted to the floor surface when passing through the resonance rotation can be minimized, and the vibration transmitted to the floor surface is significantly reduced above the resonance rotation. It is possible.

Further, the second means of the present invention is to provide a drum having a water passage hole on the outer periphery and rotating about a horizontal axis, a water tank containing the drum for storing washing water, and a spring body for suspending the water tank from the main body. A plurality of shock absorbers capable of suppressing the vibration of the water tank and adjusting the buffering capacity, a vibration detecting means for detecting the amplitude of the vibration of the water tank, and the output of the vibration detecting means as an input, and when the dehydration starts, the plurality of If the buffering capacity of some of the buffers is large and the output of the vibration detecting means exceeds a predetermined value when the drum reaches a first predetermined rotational speed below the resonance rotational speed, all the above-mentioned buffering is performed. When the buffer capacity of the body is increased and the output is smaller than a predetermined value, the buffer capacity of some of the plurality of buffer bodies is maintained to be high, and the second drum whose resonance speed is equal to or higher than the resonance rotation speed is maintained. Buffer capacity of all the above-mentioned buffers when the specified number of rotations is reached As a drum type washing machine equipped with a control means for controlling small, only by adjusting the cushioning capacity of the cushioning body only when the amount of unbalance is very large, the floor surface is passed through the cushioning body when passing through the resonance rotation. The vibration transmitted can be minimized, and the vibration transmitted to the floor surface can be significantly reduced when the resonance rotation or more is performed.

Further, a third means of the present invention is to provide a drum having water passage holes on its outer periphery to rotate about a horizontal axis, a water tank containing the drum for storing washing water, and a spring body for suspending the water tank from the main body. A plurality of buffer bodies that suppress the vibration of the water tank and the buffer capacity can be adjusted, and when the dehydration is started, the buffer capacity of all of the plurality of buffer bodies is increased, and the drum is rotated at a predetermined rotation speed equal to or higher than the resonance rotation speed. As a drum type washing machine equipped with a control means for controlling the buffering capacity of the plurality of buffering bodies to be successively decreased at a predetermined time interval when reaching the buffering capacity, the buffering capacity can be adjusted to be gradually smaller, and Vibrations can be minimized, vibrations transmitted to the floor surface when the cushioning capacity changes can be minimized, and vibrations transmitted to the floor surface can be significantly reduced at the resonance speed or higher. It is a thing.

[Brief description of drawings]

FIG. 1 is a side sectional view of a drum type washing machine according to an embodiment of the present invention.

FIG. 2 is a front sectional view of the drum type washing machine.

FIG. 3 is a detailed cross-sectional view of a main part of a buffer body of the drum type washing machine.

FIG. 4A is a sectional view of a main part of the drum type washing machine when the solenoid of the cushioning body is not operating. FIG. 4B is a sectional view of a main part of the drum type washing machine when the solenoid of the cushioning body is operating.

FIG. 5 is a block diagram showing a related configuration of control means of the drum type washing machine.

FIG. 6 is a flowchart from the start to the end of washing in the embodiment of the first means of the present invention.

FIG. 7 is a flowchart from the start to the end of washing in the embodiment of the second means of the present invention.

FIG. 8 is a flowchart from the start to the end of washing in the embodiment of the third means of the present invention.

FIG. 9 is a side sectional view showing a conventional drum type washing machine.

[Explanation of symbols]

 8 spring body 12 main body 14 water tank 15 drum 16 horizontal shafts 21a and 21b buffer body 24 control means 25 vibration detection means

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shunichi Iwakiri 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (3)

[Claims] 1. A drum having a water passage hole on its outer periphery and rotating about a horizontal axis, a water tank containing the drum for storing washing water, a spring body for suspending the water tank from the main body, and a vibration damping capacity of the water tank. A plurality of buffers that can be adjusted, a vibration detection unit that detects the amplitude of the vibration of the water tank, and the output of the vibration detection unit as an input, and at the start of dehydration, the buffering capacity of all the plurality of buffers. Is set to a large value, and when the output of the vibration detecting means is smaller than a predetermined value when the drum reaches a first predetermined rotation speed which is equal to or lower than the resonance rotation speed, the buffering capacity of the part of the buffer is reduced. , When the output is greater than a predetermined value, the buffer capacity of all the buffer bodies is maintained at a high level, and when the drum reaches a second predetermined rotational speed that is equal to or higher than the resonance rotational speed, the buffer capacity of all the buffer bodies. Drum type washing machine with control means for controlling Machine. 2. A drum which has a water passage hole on its outer periphery and rotates around a horizontal axis, a water tank for accommodating washing water containing the drum, a spring body for suspending the water tank from the main body, and a vibration damping capacity of the water tank. A plurality of buffers that can be adjusted, a vibration detection unit that detects the amplitude of vibration of the water tank, and an output of the vibration detection unit as an input, and a buffer of some of the plurality of buffers when starting dehydration. When the output of the vibration detecting means is greater than a predetermined value when the drum has reached a first predetermined rotational speed equal to or lower than the resonance rotational speed, the buffering capacity of all the buffer bodies is increased, When the output is smaller than a predetermined value, the buffering capacity of some of the plurality of buffer bodies is maintained to be high, and when the drum reaches a second predetermined rotational speed equal to or higher than the resonance rotational speed, With a control means that controls the buffer capacity of all buffers to a small value Drum type washing machine equipped. 3. A drum having a water passage hole on its outer periphery and rotating about a horizontal axis, a water tank for accommodating the washing water and accommodating the washing water, a spring body for suspending the water tank from the main body, and a vibration damping capacity of the water tank. A plurality of buffers that are adjustable, and the buffering capacity of all of the plurality of buffers is increased at the start of dehydration, and when the drum reaches a predetermined number of revolutions above the resonance number of revolutions, A drum-type washing machine comprising: a control unit that controls the cushioning capacity of the cushioning body to be gradually reduced at predetermined time intervals.