Drum washing machine

Abstract

To acquire a press-washing effect in which detergent water is impregnated into a mattress or the mattress is wrung.SOLUTION: A drum type washing machine can execute a washing step and a rinsing step. The drum type washing machine includes: an outer tub arranged in a housing; a drum arranged in the outer tub, and rotatable around a horizontal shaft; a drive motor for rotating the drum in a predetermined direction; and control means for controlling the drive motor. The control means controls, in the washing step and the rinsing step, the drive motor in such a manner that high-speed rotation in which the drum rotates at a larger rotational frequency than a predetermined rotational frequency and low-speed rotation in which the drum rotates at the rotational frequency equal to or less than the predetermined rotational frequency are performed.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a drum type washing machine. [Background technology]

[0002] When washing laundry in a drum-type washing machine, after the laundry is placed in the drum, the machine generally operates in the following order: washing, rinsing, and spin-drying. In the washing and rinsing processes, the water supply operation for supplying water into the drum, the washing operation for rotating the drum, and the drainage operation for draining water from the drum are carried out in that order, followed by the spin-drying operation.

[0003] During the washing operation, a horizontal-axis drum is rotated inside an outer tub with water stored at the bottom, and laundry is lifted and dropped by a baffle installed inside the drum, washing the laundry by slamming it against the inner surface of the drum (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2018-33512 Summary of the Invention [Problem to be solved by the invention]

[0005] Conventionally, in a drum-type washing machine, in addition to laundry such as clothes, a mattress may be washed. In this case, like laundry such as clothes, the mattress is put into the drum, and then the washing process, the rinsing process, and the spin-drying process are performed in that order.

[0006] However, when washing a futon mattress in a drum-type washing machine, if it is simply placed in the machine and a normal beating wash is performed, the futon mattress will be biased to one side of the drum, which may result in the mattress not being able to be dehydrated or the mattress mattress itself losing its shape due to the beating wash. Therefore, when washing a futon mattress in a normal washing cycle, a possible washing method is to wrap the futon mattress with string or the like to make it difficult for it to move, and then place the futon mattress in the washing machine. However, with this method, since the futon mattress is rolled up, water is less likely to penetrate to the inside of the futon mattress than the outside, making it difficult to achieve a sufficient cleaning effect.

[0007] In addition, in washing machines with a dedicated futon course, a possible washing method is to place the futon without wrapping it with string so that it sticks evenly along the inner wall of the drum, and to keep the drum constantly rotating in a certain direction at a certain number of revolutions from the start to the end of the operation, so that the futon can be kept stuck to the inner wall of the drum. However, in order to keep the futon stuck to the inner wall of the drum, the drum needs to rotate at a higher speed than in a normal beating wash, and the centrifugal force pushes the water inside the drum out, making it difficult to achieve a sufficient washing effect.

[0008] SUMMARY OF THE PRESENT EMBODIMENTS Accordingly, an object of the present invention is to provide a drum-type washing machine capable of thoroughly washing, for example, a futon mattress without unevenness. [Means for solving the problem]

[0009] The drum-type washing machine of the present invention is a drum-type washing machine capable of performing a washing step and a rinsing step, and includes an outer tub disposed in a housing, a drum disposed in the outer tub and rotatable about a horizontal axis or an inclined axis inclined relative to the horizontal direction, a drive motor for rotating the drum in a predetermined direction, and a control means for controlling the drive motor, and the control means controls the drive motor during the washing step. At 70 rpm or more and 200 rpm or less a high speed rotation of the drum at a rotation speed; 50rpm or more and 70rpm or less and a low speed rotation in which the drum rotates at a rotation speed of Alternately To be carried out At the same time, in the rinsing step, the high speed rotation and the low speed rotation are alternately performed. The drive motor is controlled so as to The cycle for switching the rotation speed in the washing step is different from the cycle for switching the rotation speed in the rinsing step. It is characterized by:

[0012] In the drum type washing machine of the present invention, it is preferable that a cycle for switching the rotation speed in the rinsing stroke is shorter than a cycle for switching the rotation speed in the washing stroke.

[0013] In the drum type washing machine of the present invention, it is preferable that the control means controls the drive motor so that the low speed rotation is performed for a longer period of time than the high speed rotation in the washing step. Effect of the Invention

[0014] In the drum-type washing machine of the present invention, the drum is switched between two or more different rotation speeds during at least one of the washing and rinsing steps. Therefore, when rotating at high speed, the detergent water in the drum is pushed out by the centrifugal force generated when the drum rotates, and the mattress is lightly dehydrated, and when rotating at low speed, the centrifugal force generated when the drum rotates is small, and the detergent water accumulates in the drum, so that the mattress is soaked in the detergent water. Therefore, a pressing effect is obtained in which the detergent water is soaked into the mattress and the mattress is squeezed, improving the cleaning power and suppressing uneven washing.

[0015] In the drum-type washing machine of the present invention, high-speed rotation and low-speed rotation are alternately switched in at least one of the washing step and the rinsing step, so that the pressing-washing effect of soaking the mattress with detergent water and squeezing the mattress can be more effectively obtained.

[0016] In the drum-type washing machine of the present invention, the rotation speeds for high and low speed rotation can be set separately for the washing and rinsing steps, so that the strength of the pushing wash can be changed for the washing and rinsing steps. For example, the washing step can be performed with gentle pushing to allow the detergent water to soak in, and the rinsing step can be performed with strong pushing to squeeze out the detergent water from the mattress.

[0017] In the drum-type washing machine of the present invention, the cycle of switching between high and low speeds in the rinsing process can be made shorter than the cycle of switching between high and low speeds in the washing process, thereby increasing the number of times the rinsing water passes over the mattress, thereby improving the rinsing effect.

[0018] In the drum-type washing machine of the present invention, the time for the low-speed rotation in the washing process can be set longer than the time for the high-speed rotation, so that the time for soaking in detergent water can be increased. This allows the detergent water to pass through the mattress, allowing the detergent water to penetrate sufficiently into the mattress, improving the cleaning effect. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 is a perspective view of a drum type washing machine 1 according to an embodiment of the present invention. [Diagram 2] 2 is a side cross-sectional view showing the configuration of the drum-type washing machine 1 of FIG. [Diagram 3] FIG. 1 is a control block diagram of a drum-type washing machine 1. [Figure 4] 13 is a flowchart showing the operation of the washing process of the mattress cleaning course. [Diagram 5] FIG. 5(a) is a diagram showing changes in the rotation speed of drum 4 during the washing process, and FIG. 5(b) is a diagram showing changes in the rotation speed of drum 4 during the rinsing process. [Figure 6] FIG. 6(a) is a diagram showing the state of the mattress inside the drum 4 when it is rotating at a low speed, and FIG. 6(b) is a diagram showing the state of the mattress inside the drum 4 when it is rotating at a high speed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, a drum type washing machine 1 according to an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a perspective view of the drum type washing machine 1 according to the embodiment of the present invention. Fig. 2 is a side cross-sectional view showing the configuration of the drum type washing machine 1 of Fig. 1.

[0021] 1 and 2, the drum type washing machine 1 of this embodiment has a box-shaped housing 2, an outer tub 3 having a substantially cylindrical inner circumferential surface is disposed inside the housing 2, and a drum 4 having a substantially cylindrical inner circumferential surface for accommodating laundry is supported inside the outer tub 3 by a main shaft 5 extending in the front-rear direction. The drum 4 is rotatable about a horizontal axis.

[0022] The front surface of the housing 2 is formed with an operating section 2a for a user to operate, and a clothes insertion opening 6 that faces an opening 4a formed at the front end of the drum 4. The housing 2 is provided with a door 8 for opening and closing the clothes insertion opening 6, which is opened and closed by the door 8, and laundry can be put in and taken out of the drum 4 when the door 8 is open.

[0023] A plurality of baffles 4b are provided on the inner peripheral surface of drum 4 so as to protrude into drum 4. Baffles 4b are protrusions for lifting up laundry contained in drum 4. For example, during the washing process, when drum 4 is rotated by the driving force of drive motor 11 (described later), the laundry containing water inside drum 4 is lifted by baffles 4b and falls naturally, which is called beating washing.

[0024] A large number of water passage holes 4c are drilled into the inner surface of the drum 4. Water supplied to the outer tub 3 during washing and rinsing flows into the drum 4 through the water passage holes 4c, and water expelled from the laundry inside the drum 4 during centrifugal dehydration is splashed toward the outer tub 3 through these water passage holes 4c.

[0025] The main shaft 5 is rotatably supported by a bearing 5a attached to the rear wall of the outer tub 3, and a main pulley 10 is attached to the tip of the main shaft 5 that protrudes further rearward. A drive motor 11 is installed at the bottom of the housing 2, and a motor pulley 12 is attached to the rotating shaft of the drive motor 11. The torque of the motor pulley 12 is transmitted to the main pulley 10 via a timing belt 16. As a result, when the drive motor 11 is driven, the drum 4 rotates around the main shaft 5.

[0026] A water supply pipe 30 with a water supply valve 30a installed midway is connected to the upper part of the rear wall of the outer tub 3, and when the water supply valve 30a is opened, water supplied from the outside is supplied to the outer tub 3 via the water supply pipe 30. A drain pipe 31 with a drain valve 31a installed midway is connected to a drain outlet installed at the bottom of the outer tub 3, and when the drain valve 31a is opened, the water in the outer tub 3 is discharged outside the machine through the drain pipe 31.

[0027] Fig. 3 is a control block diagram of the drum type washing machine 1. As shown in Fig. 3, the control unit 50 of the drum type washing machine 1 is composed of, for example, a microcomputer, and includes a CPU, a ROM in which a program for controlling the operation of the drum type washing machine 1 is stored, and a RAM in which data used when executing the program is temporarily stored. The operation of the drum type washing machine 1 is controlled by the control unit 50. The control unit 50 is connected to an operation unit 2a, a water supply valve 30a, a drain valve 31a, and a drive motor 11.

[0028] In the drum type washing machine 1, the user can select between a standard washing course and a futon washing course by operating the operation unit 2a of the housing 2. In the drum type washing machine 1, various operation courses can be selected by operating the operation unit 2a of the housing 2, but in the following explanation, only the futon washing course will be explained.

[0029] The mattress cleaning course is a course used when washing a mattress, and the washing process, the rinsing process, and the spin-drying process are carried out in that order.

[0030] The washing step of the mattress cleaning course will be described with reference to Fig. 4. Fig. 4 is a flow chart showing the operation of the washing step of the mattress cleaning course.

[0031] <Step S1> In step S1, the control unit 50 rotates the drum 4 at a low speed. In this embodiment, the control unit 50 controls the drive motor 11 so that the drum 4 rotates at a low speed of rotation speed N1 (for example, 60 rpm). Then, the process proceeds to step S2.

[0032] <Step S2> In step S2, the control unit 50 opens the water supply valve 30a to supply water to the outer tub 3. At this time, the control unit 50 closes the drain valve 31a, and the supplied water is stored in the outer tub 3 and also stored in the drum 4 through the water passage hole 4c.

[0033] <Step S3> In step S3, the control unit 50 repeatedly determines whether the water level in the outer tub 3 has reached the set water level for the washing process. When the control unit 50 determines that the water level in the outer tub 3 has reached the set water level, the control unit 50 closes the water supply valve 30a and proceeds to step S4.

[0034] <Step S4> In step S4, the control unit 50 determines whether the drum 4 is rotating at a low speed. If the control unit 50 determines that the drum 4 is rotating at a low speed, the process proceeds to step S5. If the control unit 50 determines that the drum 4 is not rotating at a low speed, the process proceeds to step S7.

[0035] <Step S5> In step S5, the control unit 50 determines whether or not a predetermined time T1 has elapsed since the low-speed rotation of the drum 4 was started. In this embodiment, the predetermined time T1 is, for example, 60 seconds. If the control unit 50 determines that the predetermined time T1 has elapsed since the low-speed rotation of the drum 4 was started, the process proceeds to step S6. If the control unit 50 determines that the predetermined time T1 has not elapsed since the low-speed rotation of the drum 4 was started, the process proceeds to step S9.

[0036] <Step S6> In step S6, since the low-speed rotation of the drum 4 has continued for a predetermined time T1, the control unit 50 starts high-speed rotation of the drum 4. In this embodiment, the control unit 50 controls the drive motor 11 so that the drum 4 rotates at a high speed of rotation speed N2 (e.g., 80 rpm). Then, the process proceeds to step S9.

[0037] <Step S7> In step S7, the control unit 50 determines whether or not a predetermined time T2 has elapsed since the high-speed rotation of the drum 4 was started. In this embodiment, the predetermined time T2 is, for example, 30 seconds. If the control unit 50 determines that the predetermined time T2 has elapsed since the high-speed rotation of the drum 4 was started, the process proceeds to step S8. If the control unit 50 determines that the predetermined time T2 has not elapsed since the high-speed rotation of the drum 4 was started, the process proceeds to step S9.

[0038] <Step S8> In step S8, since the high-speed rotation of the drum 4 has continued for the predetermined time T2, the control unit 50 starts the low-speed rotation of the drum 4. Then, the process proceeds to step S9.

[0039] <Step S9> In step S9, the control unit 50 determines whether the washing step has ended. In this embodiment, the time required for the washing step is set in advance, and the washing step ends when the required time has elapsed after the low-speed rotation of the drum 4 is started in step S1. If the control unit 50 determines that the washing step has ended, the process proceeds to step S10. If the control unit 50 determines that the washing step has not ended, the process proceeds to step S4.

[0040] <Step S10> In step S10, since the washing cycle has ended, the control unit 50 opens the drain valve 31a to drain the wash water in the outer tub 3 to the outside of the machine via the drain pipe 31, thereby ending the process.

[0041] FIG. 5(a) shows the change in the rotation speed of the drum 4 during the washing step described above. When the washing step is started, the drum 4 starts to rotate at a low speed. That is, in this embodiment, the low speed rotation of the drum 4 at a rotation speed N1 (e.g., 60 rpm) continues for a predetermined time T1 (e.g., 60 sec). When the low speed rotation of the drum 4 continues for the predetermined time T1, the drum 4 is switched to a high speed rotation. That is, in this embodiment, the high speed rotation of the drum 4 at a rotation speed N2 (e.g., 80 rpm) continues for a predetermined time T2 (e.g., 30 sec). After the high speed rotation of the drum 4 continues for the predetermined time T2, the low speed rotation and the high speed rotation are alternately repeated in the same manner as described above until the required time for the washing step has elapsed.

[0042] In the rinsing step of the mattress cleaning course, the drum 4 is rotated alternately between low speed and high speed, similarly to the washing step described above.

[0043] The difference between the washing step and the rinsing step is the drum rotation speed during low-speed and high-speed rotation of the drum 4 and the predetermined time for which that rotation speed is continued. That is, in the washing step, low-speed rotation at drum rotation speed N1 for a predetermined time T1 and high-speed rotation at drum rotation speed N2 for a predetermined time T2 are alternately repeated, whereas in the rinsing step, low-speed rotation at drum rotation speed N3 for a predetermined time T3 and high-speed rotation at drum rotation speed N4 for a predetermined time T4 are alternately repeated.

[0044] 4, if the predetermined time T3 has elapsed instead of the predetermined time T1 in step S5, and the predetermined time T4 has elapsed instead of the predetermined time T2 in step S7, the flow chart will become one showing the operation of the rinsing step. Note that when determining whether the rinsing step has ended in step S9, a preset required time for the rinsing step is used.

[0045] FIG. 5(b) shows the change in the rotation speed of the drum 4 during the rinsing step. When the rinsing step is started, the drum 4 starts to rotate at a low speed. That is, in this embodiment, the drum 4 continues to rotate at a low speed N3 (e.g., 60 rpm) for a predetermined time T3 (e.g., 60 sec). When the low speed rotation of the drum 4 continues for the predetermined time T3, the drum 4 is switched to a high speed rotation. That is, in this embodiment, the drum 4 continues to rotate at a high speed N4 (e.g., 100 rpm) for a predetermined time T4 (e.g., 30 sec). After the high speed rotation of the drum 4 continues for the predetermined time T4, the low speed rotation and the high speed rotation are alternately repeated in the same manner as described above until the required time for the rinsing step has elapsed.

[0046] In the drum type washing machine 1 of this embodiment, the rotation speed during low speed rotation is set to a rotation speed (e.g., 50 to 70 rpm) at which the centrifugal force during drum rotation is small, detergent water accumulates in the drum 4, and the mattress is soaked in the detergent water, as shown in Fig. 6(a). This allows the detergent water to soak into the mattress.

[0047] The rotation speed during high-speed rotation is set to a rotation speed (e.g., 70 to 100 rpm) at which the detergent water in the drum 4 is pushed out by the centrifugal force generated when the drum rotates and the mattress is lightly dehydrated, as shown in Fig. 6(b). This allows the detergent water to be squeezed out from the mattress.

[0048] In this way, in the drum type washing machine 1 of this embodiment, low and high speed rotation can be switched at regular intervals, so that the mattress is repeatedly soaked in detergent water and wrung out, thereby achieving a press-wash effect.

[0049] In addition, in the washing process, in order to prolong the time that the mattress is soaked in detergent water, the predetermined time T1 during low-speed rotation is set longer than the predetermined time T2 during high-speed rotation. This allows the detergent water to pass through the mattress and penetrate sufficiently into the mattress, improving the cleaning effect.

[0050] In contrast, in the rinsing process, the predetermined time T3 during low-speed rotation and the predetermined time T4 during high-speed rotation are set to be the same in order to push out the detergent components that have soaked into the mattress. This increases the number of times the rinsing water passes through the mattress, thereby improving the rinsing effect.

[0051] The drum type washing machine 1 of this embodiment is a drum type washing machine capable of performing a washing process and a rinsing process, and comprises an outer tub 3 arranged in a housing 2, a drum 4 arranged in the outer tub 3 and rotatable around a horizontal axis, a drive motor 11 for rotating the drum 4 in a predetermined direction, and a control unit 50 which is a control means for controlling the drive motor 11. The control unit 50 controls the drive motor 11 so that, during the washing process and the rinsing process, high-speed rotation is performed in which the drum 4 rotates at a rotation speed higher than a predetermined rotation speed, and low-speed rotation is performed in which the drum 4 rotates at a rotation speed equal to or lower than the predetermined rotation speed.

[0052] As a result, in the drum type washing machine 1 of this embodiment, the drum 4 is switched between two or more different rotation speeds in at least one of the washing and rinsing strokes. Therefore, during high-speed rotation, the detergent water in the drum 4 is pushed out by the centrifugal force generated when the drum rotates, and the mattress is lightly dehydrated, and during low-speed rotation, the centrifugal force generated when the drum rotates is small, and the detergent water accumulates in the drum 4, so that the mattress is soaked in water. This provides a pressing effect that soaks the mattress with detergent water and squeezes the mattress, improving the cleaning power and suppressing uneven washing.

[0053] In the drum type washing machine 1 of this embodiment, the control unit 50, which is a control means, controls the drive motor 11 so as to alternate between high speed rotation and low speed rotation in the washing process and the rinsing process.

[0054] As a result, in the drum type washing machine 1 of this embodiment, the rotation speeds for high speed rotation and low speed rotation can be set individually in the washing process and the rinsing process. Therefore, the strength of the pressing wash in the washing process and the rinsing process can be changed. For example, in the washing process, the pressing wash can be performed softly to allow the detergent water to soak in, and in the rinsing process, the pressing wash can be performed strongly to squeeze out the detergent water from the mattress.

[0055] In the drum type washing machine 1 of this embodiment, the control unit 50, which is a control means, controls the drive motor 11 to alternate between high and low rotation speeds in the washing process and to alternate between high and low rotation speeds in the rinsing process, and the period Ta for switching the rotation speed in the washing process (the sum of the specified time T1 for high rotation speed and the specified time T2 for low rotation speed) is different from the period Tb for switching the rotation speed in the rinsing process (the sum of the specified time T3 for high rotation speed and the specified time T4 for low rotation speed).

[0056] As a result, in the drum type washing machine 1 of this embodiment, the rotation speeds for high speed rotation and low speed rotation can be set individually in the washing process and the rinsing process. Therefore, the strength of the pressing wash in the washing process and the rinsing process can be changed. For example, in the washing process, the pressing wash can be performed softly to allow the detergent water to soak in, and in the rinsing process, the pressing wash can be performed strongly to squeeze out the detergent water from the mattress.

[0057] In the drum type washing machine 1 of the present embodiment, the period Tb for switching the rotation speed in the rinsing stroke is shorter than the period Ta for switching the rotation speed in the washing stroke.

[0058] As a result, in the drum-type washing machine 1 of this embodiment, the cycle Tb for switching the rotation speed in the rinsing process can be made shorter than the cycle Ta for switching the rotation speed in the washing process, thereby increasing the number of times the press-wash is performed. Therefore, by increasing the number of times the rinsing water passes through the mattress, the rinsing effect can be improved.

[0059] In the drum type washing machine 1 of this embodiment, the control unit 50, which is a control means, controls the drive motor 11 so that the low-speed rotation is performed for a longer period of time than the high-speed rotation in the washing process.

[0060] As a result, in the drum type washing machine 1 of this embodiment, the time for low-speed rotation in the washing process can be set longer than the time for high-speed rotation, and the time for soaking in detergent water can be increased. This allows the detergent water to pass through the mattress, allowing the detergent water to fully penetrate into the mattress, improving the cleaning effect.

[0061] Although the embodiment of the present invention has been described above, the specific configuration of each part is not limited to the above-described embodiment.

[0062] For example, in the above embodiment, the drum rotation speed setting in the washing step and the rinsing step can be switched between two levels, but is not limited thereto. For example, the drum rotation speed setting in the washing step and the rinsing step may be switched between three or more levels.

[0063] In the above embodiment, a case has been described in which the drum 4 rotates at low and high speeds during both the washing and rinsing steps, but the drum 4 may rotate at low and high speeds only during some of the washing and rinsing steps.

[0064] In the above embodiment, the drum rotation speeds N1 and N2 are shown in the washing step of the mattress cleaning course, and the drum rotation speeds N3 and N4 are shown in the rinsing step, but they can be set arbitrarily. For example, the drum rotation speeds N1 and N3 during low-speed rotation may be, for example, 50 to 70 rpm, and the drum rotation speeds N3 and N4 during high-speed rotation may be, for example, 70 to 200 rpm, and preferably 70 to 100 rpm.

[0065] In the above embodiment, the low-speed drum rotation speed N1 and the high-speed drum rotation speed N2 are always constant in the washing step, but at least one of the low-speed drum rotation speed N1 and the high-speed drum rotation speed N2 may be changed for each cycle Ta. For example, by changing the high-speed drum rotation speed N2 in the washing step, the washing can be made stronger or weaker. The same applies to the rinsing step in that at least one of the low-speed drum rotation speed N3 and the high-speed drum rotation speed N4 may be changed for each cycle Tb.

[0066] In the above embodiment, specific examples of the predetermined time T1 for low-speed rotation and the predetermined time T2 for high-speed rotation for the washing process of the mattress cleaning course are shown, and specific examples of the predetermined time T3 for low-speed rotation and the predetermined time T4 for high-speed rotation for the rinsing process are shown, but they can be set arbitrarily.

[0067] In the above embodiment, the predetermined time T1 for low speed rotation and the predetermined time T2 for high speed rotation in the washing step are always constant, but at least one of the predetermined time T1 for low speed rotation and the predetermined time T2 for high speed rotation may be changed for each cycle Ta. For example, by changing the predetermined time T2 for high speed rotation in the washing step, the washing can be made stronger or weaker. The same applies to the rinsing step in that at least one of the predetermined time T1 for low speed rotation and the predetermined time T2 for high speed rotation may be changed for each cycle Tb.

[0068] In the above embodiment, the cycle Tb for switching the rotation speed in the rinsing step is shorter than the cycle Ta for switching the rotation speed in the washing step, but this is not limited to this. In the above embodiment, the low-speed rotation is performed longer than the high-speed rotation in the washing step, but this is not limited to this. In the above embodiment, the high-speed rotation time T3 and the low-speed rotation time T4 are set to be the same in the rinsing step, but this is not limited to this.

[0069] In the above embodiment, the case of washing a futon mattress has been described, but the present invention can also be applied to cases where a futon other than a futon mattress is washed. In the above embodiment, the drum type washing machine 1 capable of performing the washing process, the rinsing process, and the spin-drying process has been described, but the present invention can also be applied to a washing and drying machine capable of performing the washing process, the rinsing process, the spin-drying process, and the drying process. [Explanation of symbols]

[0070] 1. Drum type washing machine 2. Chassis 3 Outer tank 4 Drums 11 Drive motor 50 Control section (control means)

Claims

1. A drum-type washing machine capable of performing a washing step and a rinsing step, An outer tank disposed within the housing; A drum is disposed in the outer tub and is rotatable about a horizontal axis or an inclined axis inclined relative to the horizontal direction; A drive motor for rotating the drum in a predetermined direction; A control means for controlling the drive motor, The control means In the washing step, a high-speed rotation in which the drum rotates at a rotation speed of more than 70 rpm and not more than 200 rpm and a low-speed rotation in which the drum rotates at a rotation speed of 50 rpm or more and not more than 70 rpm are alternately performed, controlling the drive motor so that the high speed rotation and the low speed rotation are alternately performed during the rinsing stroke; The drum type washing machine is characterized in that a cycle for switching the rotation speed in the washing step is different from a cycle for switching the rotation speed in the rinsing step.

2. 2. The drum type washing machine according to claim 1, wherein a cycle for switching the rotation speed in the rinsing step is shorter than a cycle for switching the rotation speed in the washing step.

3. 3. The drum type washing machine according to claim 1, wherein the control means controls the drive motor so that the low speed rotation is performed for a longer period of time than the high speed rotation in the washing step.

Images