JP5957698B2 - Drum washing machine - Google Patents

Description

  The present invention relates to a drum type washing machine for washing clothes and the like.

  The conventional drum type washing machine uses less water than the vertical washing machine, and not all the laundry in the aquarium is immersed in the washing water, so the washing water in the aquarium is circulated into the rotating tub by a pump. It is ejected onto the laundry (see, for example, Patent Document 1).

  Moreover, the drum type washing machine of patent document 1 is made to wash efficiently by controlling the water level and pump in a rotation tank so that the air pump of a circulation pump may not be raise | generated.

JP 2010-253099 A

  However, in the above-described conventional configuration, only the water level in the rotating tub is detected in order to prevent the air of the circulation pump from being caught. However, in actuality, it is also affected by the water flow generated by the rotation of the rotating tub during washing. Since the flow of water varies depending on the rotation direction of the rotating tank, there is a problem that it is difficult to completely suppress the occurrence of air biting in the pump only by controlling the pump uniformly regardless of the rotating direction of the rotating tank. Was.

  The present invention solves the above-described conventional problems, and is a drum type washing machine having excellent washing efficiency by suppressing the occurrence of air biting of the circulation pump regardless of factors such as the rotation direction of the rotating tub in the washing process. The purpose is to provide.

In order to solve the above-described conventional problems, the drum type washing machine of the present invention includes a water tank for storing washing water, a rotary tank rotatably disposed in the water tank and provided with an opening on the front side, and the rotation A motor for driving the tank, a concave drainage groove formed in a lower portion of the water tank, a drainage port provided at a bottom of the drainage groove and located laterally from a center line of the drainage groove, and the drainage port A circulating water path that circulates the washing water in the water tank to the rotating tank, and a pump that supplies the washing water in the water tank to the circulating water path,
The pump is configured such that when the rotary tub rotates in the direction from the drain outlet side toward the center of the drain groove at the lower part, the total driving time is shorter than that in the reverse rotation.

  With such a configuration, the occurrence of air biting of the circulation pump can be suppressed regardless of factors such as the rotation direction of the rotating tub in the washing process.

  The drum type washing machine of the present invention can improve washing efficiency by suppressing the occurrence of air biting of the circulation pump.

Sectional drawing which shows schematic structure of the washing machine in Embodiment 1 of this invention. Cross-sectional view of the main part seen from the front of the drum type washing machine and a schematic diagram showing the flow of washing water The time chart which shows the operation | movement at the time of washing of the washing machine in Embodiment 1 of this invention Time chart showing the operation of a conventional washing machine during washing Time chart showing operation during washing of washing machine in embodiment 2 of the present invention Sectional drawing of the principal part seen from the front of the washing machine in Embodiment 3 of this invention Sectional drawing of the principal part seen from the upper surface of the washing machine in Embodiment 3 of this invention Time chart showing operation during washing of washing machine in embodiment 4 of the present invention Time chart showing operation at the time of washing of washing machine in embodiment 5 of the present invention Time chart showing the operation of the washing machine in washing according to the sixth embodiment of the present invention Time chart showing operation during washing of washing machine in embodiment 7 of the present invention

  The washing machine of the present invention includes a water tank for storing washing water, a rotary tank rotatably disposed in the water tank and provided with an opening on the front side, a motor for driving the rotary tank, and a lower part of the water tank. A concave drainage groove formed, a drainage port provided at the bottom of the drainage groove and located laterally from the centerline of the drainage groove, communicated with the drainage port, and washing water in the water tank is A circulating water channel that circulates to the rotating tub, and a pump that supplies the washing water in the water tub to the circulating water channel, and the pump is disposed at a lower portion from the drain port side to the center of the drain groove. When rotating in the direction of heading, the total driving time is shorter than in reverse rotation.

  With such a configuration, it is possible to suppress the air biting of the circulation pump that occurs due to the influence of the water flow that occurs when the rotating tub rotates in the direction from the drain outlet side toward the center of the drain groove at the lower part.

  The said structure WHEREIN: The said pump may be made to perform control according to the rotation direction of the said rotation tank in the washing process.

  With such a configuration, the air biting can be suppressed even under conditions where the air biting of the pump is promoted by foaming caused by the detergent components contained in the washing liquid during the washing process.

  In the above configuration, the pump has a motor with a variable rotation speed, and when the motor is equal to or higher than a predetermined rotation speed, the pump has the rotary tank at a lower portion from the drain port side toward the center of the drain groove. When rotating in the direction, the total driving time may be shorter than in reverse rotation.

  With such a configuration, it is possible to reliably suppress the air biting when the operation is performed under the condition where the air bite is more likely to occur.

  The said structure WHEREIN: You may make it form the upper extension rib which covers a drain outlet in the side wall at the side of the drain outlet of a drainage groove.

  With such a configuration, when the rotation direction of the rotary tank in the vicinity of the drainage groove is directed from the centerline side of the drainage groove to the drainage port side, the generation of air biting is more reliably suppressed by the water flow generated by the rotation of the rotary tank. can do.

  The said structure WHEREIN: When the said rotation tank rotates in the direction which goes to the center of the said drain groove from the said drain outlet side in the lower part, you may make rotation speed low compared with the time of reverse rotation.

  With such a configuration, the water flow generated by the rotation of the rotating tank is reduced, and the occurrence of air biting can be more reliably suppressed.

  The said structure WHEREIN: When the said rotation tank rotates in the direction which goes to the center of the said drain groove from the said drain outlet side in the lower part, you may make it shorten rotation time compared with the time of reverse rotation.

  With such a configuration, the time during which the water flow generated by the rotation of the rotating tub is affected is shortened, and the occurrence of air biting can be more reliably suppressed.

The washing machine of the present invention includes a water tank for storing washing water, a rotary tank rotatably disposed in the water tank and provided with an opening on the front side, a motor for driving the rotary tank, and a lower part of the water tank. A concave drainage groove formed, a drainage port provided at the bottom of the drainage groove and located laterally from the centerline of the drainage groove, communicated with the drainage port, and washing water in the water tank is A circulation channel for circulation to the rotating tank;
A pump for feeding the washing water in the water tank to the circulation water channel, the pump having a motor with a variable rotation speed, and the pump is configured so that the rotary tank is formed in the lower part from the drain outlet side to the drain groove. When rotating in the direction toward the center of the motor, the number of rotations to drive is lower than in the case of reverse rotation.

  With such a configuration, it is possible to suppress the air biting of the circulation pump that occurs due to the influence of the water flow that occurs when the rotating tub rotates in the direction from the drain outlet side toward the center of the drain groove at the lower part.

  Hereinafter, a washing machine according to an embodiment of the present invention will be described with reference to the drawings. The following embodiments are examples embodying the present invention, and do not limit the technical scope of the present invention.

(Embodiment 1)
Embodiment 1 of the present invention will be described below with reference to the drawings. 1 is a cross-sectional view showing a schematic structure of a washing machine according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view of a main part of the drum type washing machine in the first embodiment of the present invention. FIG. 3 is a time chart showing an operation during washing of the drum type washing machine in the first embodiment of the present invention.

  1 to 3, a water tank 2 formed in a bottomed cylindrical shape is elastically supported in a housing 1. A rotating tank 4 formed in a bottomed cylindrical shape is disposed in the water tank 2 so as to be rotatable. The rotation axis 10 of the rotating tub 4 substantially coincides with the cylindrical center line of the rotating tub 4, and this substantially coincides with the cylindrical center line of the water tub 2. The water tank 2 and the rotating tank 4 are each provided with openings 5 and 6 on the front side. With the opening 5 side of the water tank 2 being the front side of the housing 1, the rotation axis 10 of the rotating tank 4 is supported by being inclined upward (for example, 10 to 20 degrees) from the horizontal direction. When the rotation axis 10 is inclined upward, a deep water storage state can be obtained with a small amount of water, and water saving can be improved. However, the rotation axis 10 may be horizontal if water saving is not taken into consideration.

  Opposite to the opening 5 of the water tank 2 and the opening 6 of the rotating tank 4, a door body 7 that can be opened and closed is provided on the front surface of the housing 1. The user can put the laundry in and out of the rotating tub 4 by opening the door body 7. A flexible bellows 8 formed of an elastic body such as rubber is disposed around the opening 5 of the water tank 2. When the door body 7 is closed, one end of the bellows 8 is in pressure contact with the inner surface thereof, and the opening 5 and the door body 7 are sealed.

  A motor 9 that rotationally drives the rotating tub 4 is attached to the end surface of the water tub 2 opposite to the opening 5. The rotor of the motor 9 is connected to the rotating tub 4 by the rotating shaft center 10 of the rotating tub 4, and the rotation of the motor 9 is transmitted to the rotating tub 4 by the rotating shaft 10. A plurality of protrusions 12 are provided on the peripheral wall of the rotating tub 4 so as to protrude toward the rotation axis 10. As the rotating tub 4 rotates, the laundry is hooked by the protrusion 12 and lifted upward, and a stirring operation is performed in which the laundry is dropped from a certain height.

  A plurality of small holes 13 are provided in the peripheral wall of the rotating tub 4 over the entire circumference. When the washing water in the water tub 2 accumulates at a predetermined water level, the washing water enters the rotating tub 4 from the small holes 13. It is configured as follows.

  Above the water tank 2, a detergent container 14 for storing detergent is provided. The detergent container 14 is connected to a water supply valve 15 connected to a water tap, and the supply and stop of tap water to the detergent container 14 is performed by opening and closing the water supply valve 15.

  A concave drainage groove 3 is provided at the bottom of the inner bottom of the water tank 2. In the vicinity of the bottom of the drainage groove 3 and the lowest point of the water tank 2, a drain port 17 for discharging the washing water in the water tank 2 is provided. The drain port 17 is formed so as to be located closer to the side than the center line 3a of the drain groove 3. A drainage path 18 that guides the washing water discharged from the drainage port 17 to the outside of the housing 1 is provided downstream of the drainage port 17. A drain valve 19 that opens and closes the drain path 18 is provided in the middle of the drain path 18.

  A circulation channel 20 through which the washing water discharged from the water tank 2 is led into the water tank 2 through the rotating tank 4 is connected to the drain port 17. The circulation water channel 20 is branched from the drainage channel 18 on the way. A pump 21 is provided in the middle of the circulation water channel 20. When the pump 21 is driven, the washing water in the water tank 2 is drawn into the circulation water channel 20 from the drain port 17. The washing water flowing into the circulation channel 20 is pressurized by the pump 21 and is sent to the rotating tub 4. In this way, the washing water is discharged again to the water tank 2 through the circulation water channel 20.

  Inside the front part of the water tank 2, a nozzle water channel 22 is provided on the outer peripheral side of the circular opening part 5 provided in the water tank 2 when viewed from the opening part 6 side of the rotating tank 4.

  The washing water in the water tank 2 fed by the pump 21 is ejected from the nozzle water path 22 toward the bottom of the rotating tank 4 through the circulation water path 20 as indicated by an arrow a.

  As shown in FIGS. 2A and 2B, the drainage port 17 is provided in the vicinity of one side wall 3 b of the concave drainage groove 3. Therefore, washing water and foam are easily discharged during drainage and dehydration. That is, when the rotating tub 4 rotates in the direction of arrow A in FIG. 2A, the flow of washing water and foam around the rotating tub 4 opposes the side wall 3b as represented by the broken line arrow A ′. A turbulent flow is caused around the side wall 3c on the side, and the discharge to the drain port 17 is not performed well. On the other hand, when the rotating tub 4 rotates in the direction of arrow B in FIG. 2B, the flow of washing water and foam around the rotating tub 4 passes through the side wall 3b from the drainage groove 3 as indicated by the broken line arrow B ′. The water is immediately discharged to the drain port 17. Here, the rotation direction A is defined as a direction in which the rotary tank 4 is directed from the drain port 17 side toward the center 3 a of the drain groove 3 in the lower part of the rotary tank 4. The rotation direction B is the reverse rotation direction of the rotation direction A, and the rotation tank 4 is defined as a direction from the center 3 a of the drainage groove 3 toward the drainage port 17 in the lower part of the rotation tank 4.

  Control means for controlling the motor 9, the water supply valve 15, the drain valve 19, the pump 21, and the like in the lower rear part in the housing 1 and controlling the operations of washing, rinsing and dehydration processes based on a set program. 32 is provided.

  Hereinafter, the operation and action of the drum type washing machine configured as described above will be described. FIG. 3 is a time chart showing the operation of the washing process of the drum type washing machine in the first embodiment of the present invention.

  When the user opens the door body 7 and puts the laundry into the rotating tub 4 and starts operation, the control means 32 detects the amount of the loaded laundry. Thereafter, the water supply valve 15 is opened, the washing water dissolves the laundry detergent stored in the detergent container 14, and the washing water is supplied into the water tank 2.

  Washing water stored in the water tank 2 is detected by a water level detection means 16 communicating with the lower part of the water tank 2. When the amount of water set according to the amount of laundry is stored, the control means 32 stops water supply and starts washing. The rotating tub 4 is driven to rotate in the forward and reverse directions by the motor 9, and the laundry accommodated in the rotating tub 4 is lifted in the rotating direction by the protrusion 12 and then dropped, and the laundry is washed by the action of tapping. The

  The water level of the washing water is set such that the laundry falls to the washing water so that the effect of tapping washing can be obtained, and the washing water is stored in the lower part of the rotating tub 4. However, in a state where the water level in the water tank 2 is low, the washing water is difficult to reach the entire laundry. For this reason, when the pump 21 is operated so as to drop the washing water on the laundry in the rotating tub 4, the washing water in the water tub 2 is drawn into the circulation channel 20 from the drain port 17 provided at the bottom of the water tub 2. Then, it is ejected toward the bottom of the rotary tank 4 through the nozzle water channel 22.

  In the washing and rinsing process of the drum type washing machine, the pump 21 is driven intermittently. As a result, the washing water is uniformly supplied to the entire laundry in the rotating tub 4. When the pump 21 is driven, the washing water is sufficiently supplied to the laundry in the vicinity of the opening 6 of the rotating tub 4 so that the laundry contains water. On the other hand, the water level in the rotating tub 4 is lowered, and the laundry near the bottom 11 of the rotating tub 4 becomes difficult to get wet. On the contrary, when the pump 21 is stopped, the laundry near the opening 6 of the rotating tub 4 is difficult to get wet, and the moisture content decreases. On the other hand, since the water level in the rotating tub 4 is higher than when the pump 21 is driven, the laundry near the bottom 11 of the rotating tub 4 is sufficiently wetted. With these actions, the water content and dewatering are alternated by driving the pump 21 intermittently. That is, by intermittently driving the pump 21, even if the laundry is filled and put into the rotating tub 4, the laundry located in any of the opening 6 and the bottom 11 of the rotating tub 4 is also sufficiently wetted alternately. be able to.

  Here, when the rotation direction of the rotating tub 4 is A, the total Σt1 of the time t1 when the pump 21 is driven is defined as T1. The total Σt2 of the time t2 when the pump 21 is driven when the rotation direction of the rotating tub 4 is B is defined as T2. In the present embodiment, the pump 21 is controlled so that T2 is shorter than T1 (T1> T2). Thereby, regardless of the flow of the washing water in the vicinity of the drainage groove 3, that is, regardless of the rotation direction of the rotating tub 4, the occurrence of air biting is suppressed.

  This will be described in detail. FIG. 4 is a time chart showing the operation of the washing process of the conventional drum type washing machine. As shown in FIG. 4, the drive time of the pump 21 is usually linked with the rotational drive of the rotary tank 4. For example, the driving of the rotary tank 4 is repeated with “12 seconds in the rotation direction A, 2 seconds as the stationary time, 12 seconds in the rotational direction B, 2 seconds as the stationary time” as one unit. Repeatedly “7 seconds drive, 7 seconds rest” in conjunction. That is, the total time during which the pump 21 is driven is equal between the rotation direction A and the rotation direction B.

  Here, generally, whether or not the pump 21 engages with air depends on the water level in the rotating tub 4. When the pump 21 is driven, as described above, the washing water is supplied to the laundry in the rotating tub 4 and the water is contained therein, thereby lowering the water level in the rotating tub 4. Therefore, the water level is different at the start of driving of the pump 21 and at the end of driving (a state in which the laundry contains water), and the water level at the end of driving is important for setting the water level so as not to chew the air.

  However, even if the water level in the rotating tub 4 is the same, the frequency of occurrence of the air biting of the pump 21 and the degree of air biting generated may vary greatly depending on the rotation direction of the rotating tub 4. Details will be described with reference to FIGS.

  As shown in FIG. 2A, when the rotation direction of the rotating tub 4 is A, the washing water flow A ′ becomes turbulent in the drainage groove 3 part. The discharge of the wash water from the drain port 17, that is, the suction of the wash water viewed from the pump 21, is hindered because it is in the opposite direction to the flow. As a result, air biting is likely to occur. On the other hand, as shown in FIG. 2B, when the rotation direction of the rotating tub 4 is B, the washing water flow B ′ discharges the washing water from the drain port 17, that is, sucks the washing water as seen from the pump 21. Facilitate. For this reason, the probability of occurrence of air biting becomes very low. That is, the water level A at which the pump 21 begins to bite when the rotation direction of the rotary tank 4 is B is lower than the water level A at which the pump 21 begins to bite when the rotation direction of the rotary tank 4 is A (water level). A> water level b).

  Therefore, even if the amount of water in the rotating tub 4 is the same, the frequency of occurrence of the air biting of the pump 21 and the degree of air biting generated vary greatly depending on the rotation direction of the rotating tub 4. When the total time during which the pump 21 is driven is equal in the rotation direction A and in the rotation direction B, it is necessary to set the water level sufficiently high so that the air does not engage even in the rotation direction A. However, in this case, there is a problem that an unnecessarily large amount of water is required only for preventing air biting.

  Therefore, as shown in FIG. 3, the present invention provides a total time for driving the pump 21 when the rotation direction of the rotary tank 4 is A, rather than the total time T1 for driving the pump 21 when the rotation direction of the rotary tank 4 is B. The pump 21 is controlled so that the time T2 is shortened (T1> T2). Thereby, regardless of the flow of the washing water in the vicinity of the drainage groove 3, that is, regardless of the rotation direction of the rotating tub 4, the occurrence of air biting is suppressed. That is, in the rotation direction A, the pump drive is stopped at a short time t2 (for example, about 4 seconds) that does not reach the air biting start water level A, and in the rotation direction B, the time that the pump drive does not reach the air biting start water level A Stop at t2 (for example, about 10 seconds). This prevents air biting without unnecessarily high water level setting. Further, in order to further prevent the air from being caught, the pump 21 may not be driven in the rotation direction A.

  When a predetermined washing time has elapsed, the drain valve 19 is opened, and the washing water in the water tank 2 is drained through the drain path 18. After the drainage is completed, the washing water for rinsing is newly supplied, and the rinsing process is executed. The operation of the rotating tub 4 in the rinsing process is the same as in the washing process. In the rinsing process, the pump 21 is driven and the washing water for rinsing is discharged. Rinsing is effectively performed by supplying the washing water for rinsing to the entire laundry in the rotating tub 4 evenly.

  When the predetermined number of rinsing steps are completed, the drain valve 19 is opened and the rinsing water in the water tank 2 is drained. The rotating tub 4 rotates at a high speed, and the washing water for rinsing contained in the laundry is dehydrated. When the dehydration step is executed for a predetermined time, the operation is finished. In addition, a drying apparatus may be provided and a drying process may be performed following a dehydration process.

  As described above, the drum type washing machine of the present invention can improve the washing efficiency by suppressing the occurrence of air biting of the pump 21 regardless of factors such as the rotation direction of the rotating tub 4 in the washing process. .

Moreover, in the said structure, since a washing | cleaning process contains a detergent component especially in a washing process, it tends to produce foaming rather than a rinse process. Also, the foaming of the washing liquid promotes the occurrence of air biting. That is, the washing process that is more easily foamed makes it easier for the pump 21 to engage with air than the rinsing process. For this reason, in the washing process rather than the rinsing process, as described above, when the rotation direction of the rotating tub 4 is A, the pump 21 when the rotation direction of the rotating tub 4 is A than the total time T1 when the pump 21 is driven when the rotation direction is B. It is more effective to suppress the air-engagement when the total time T2 for driving is shortened (T1> T2).

(Embodiment 2)
FIG. 5 is a time chart showing the operation during washing of the drum type washing machine in the second embodiment of the present invention. The present embodiment is different from the first embodiment in that the pump 21 has a variable speed motor. The other configurations and operations use the first embodiment. Only the differences will be described below.

  The pump 21 includes, for example, a DC brushless motor capable of controlling the rotation speed. When a DC brushless motor is used, the flow rate and flow rate of the circulating water discharged are adjusted. The pump 21 can change the angle of the discharged circulating water in the vertical direction and the degree of spread in the horizontal direction. As a result, the pump 21 can supply the circulating water evenly and optimally to the laundry in the rotary tub 4, and the washing performance and the rinsing performance can be enhanced. Further, the current of the pump motor 109 is input to the control means 32 by the current detection means, and it is detected whether or not an appropriate current is consumed.

  In the present embodiment, the rotational speed of the pump 21 is variably controlled along with the rotation of the rotating tub 4. In the first step of the washing and rinsing step of the drum type washing machine, the rotational speed of the pump 21 is set high (for example, 4000 rpm) so as to circulate more washing water. In the second step, the rotational speed of the pump 21 is set lower (for example, 2500 rpm) than in the first step in order to suppress abnormal foaming caused by the detergent. The first step and the second step are repeated as appropriate.

  Here, as shown in FIG. 5 (a), in the second step, since the amount of washing water circulated by the pump 21 is small, air biting hardly occurs regardless of the rotation direction of the rotating tub 4. On the other hand, in the first step, since the amount of washing water circulated is large, air biting is likely to occur depending on the rotation direction of the rotating tub 4. Therefore, as in the first embodiment, when the rotation direction of the rotating tub 4 is A, the pump 21 is longer than the total time T1 (H) for driving the pump 21 when the rotating direction of the rotating tub 4 is B. Is controlled so that the total time T2 (H) for driving is shortened (T1 (H)> T2 (H)). In this way, air biting can be suppressed.

  However, in the second step where the circulation amount of the washing water is small, if the control is performed so that (T1 (L)> T2 (L)) as in the first step, the laundry in the rotary tub 4 is discharged. There is an adverse effect that the supply of washing water, that is, the washing efficiency becomes uneven. The driving time of the pump 21 here is, for example, 10 seconds for t1 (H) and t1 (L), and 4 seconds for t2 (H) and t2 (L).

  Therefore, as shown in FIG. 5B, by setting (T1 (H)> T2 (H)) in the first step and (T1 (L) <T2 (L)) in the second step, The above adverse effects can be avoided. That is, for example, when the supply amount of washing water in the first step is approximately twice the supply amount of washing water in the second step, t1 (H) is 5 seconds, t2 (H) is 2 seconds, and t1 (L ) For 4 seconds and t2 (L) for 10 seconds, the amount of washing water supplied to the laundry in the rotating tub 4 becomes constant regardless of the rotational direction of the rotating tub 4, and the washing efficiency is uneven. It is effective in avoiding.

  Note that each embodiment of the present invention can also be implemented in combination with other embodiments. Therefore, the combination of another embodiment or a part of another embodiment is also disclosed.

(Embodiment 3)
FIG. 6 is a cross-sectional view of the main part viewed from the front of the drum type washing machine in the third embodiment of the present invention, and FIG. 7 is a cross-sectional view of the main part viewed from the top of the washing machine in the fourth embodiment of the present invention. is there. In the present embodiment, the extending rib 3 d located at the upper part covering the drainage port 17 is provided on the side wall 3 b on the drainage port 17 side of the drainage groove 3. Other configurations and operations are the same as those in the first and second embodiments. Only the differences will be described below.

  As shown in FIGS. 6A and 6B, the extending rib 3d that covers the drainage port 17 is formed on the side wall 3b of the drainage groove 3, so that the rotation direction of the rotating tub 4 is either A or B. However, since the flow A ′ and B ′ of the wash water has the effect of promoting the discharge of the wash water from the drain port 17, that is, the suction of the wash water as seen from the pump 21, it is more effective in suppressing the occurrence of air biting. is there.

  Note that each embodiment of the present invention can also be implemented in combination with other embodiments. Therefore, the combination of another embodiment or a part of another embodiment is also disclosed.

(Embodiment 4)
FIG. 8 is a time chart showing an operation during washing of the drum type washing machine in the fourth embodiment of the present invention. In this Embodiment, the rotation speed of the rotation tank 4 changes with rotation directions. Other configurations and operations are the same as those in the first and second embodiments. Only the differences will be described below.

  As shown in FIG. 2A, when the rotation direction of the rotating tub 4 is A, the washing water flow A ′ becomes a turbulent flow in the drainage groove 3. At this time, since the discharge of the washing water from the drain port 17, that is, the suction of the washing water viewed from the pump 21, is inhibited, the control is performed so that the generation of turbulent flow due to the rotation of the rotating tub 4 is suppressed. That is, the rotating tub 4 rotates at a lower rotational speed when the rotational direction is A than when the rotational direction is B. For example, the rotation speed of the rotating tank 4 is normally set to about 35 rpm at 45 rpm. Thereby, the flow A ′ of the washing water is weakened, and as a result, the occurrence of air biting is suppressed.

  Note that each embodiment of the present invention can also be implemented in combination with other embodiments. Therefore, the combination of another embodiment or a part of another embodiment is also disclosed.

(Embodiment 5)
FIG. 9 is a time chart showing an operation during washing of the drum type washing machine in the fifth embodiment of the present invention. In the present embodiment, the rotation time of the rotating tank 4 varies depending on the rotation direction of the rotating tank 4. Other configurations use Embodiments 1 to 4. Only different configurations and operations will be described below.

  As shown in FIG. 9, when the rotation direction of the rotating tub 4 is A, the washing water flow A ′ becomes a turbulent flow in the drainage groove 3 part. At this time, since the discharge of the washing water from the drain port 17, that is, the suction of the washing water viewed from the pump 21, is inhibited, the control is performed so that the generation of turbulent flow due to the rotation of the rotating tub 4 is suppressed. That is, the rotation time of the rotating tank 4 is shorter than when the rotation direction is B. For example, by controlling the place of 12 seconds normally to about 3 seconds, the period during which the washing water flow A ′ inhibits the suction of the washing water is shortened, and as a result, the occurrence of air biting is suppressed.

  Note that each embodiment of the present invention can also be implemented in combination with other embodiments. Therefore, the combination of another embodiment or a part of another embodiment is also disclosed.

(Embodiment 6)
FIG. 10 is a time chart showing the operation during washing of the drum type washing machine in the sixth embodiment of the present invention. In the present embodiment, the rotation speed of the pump 21 varies depending on the rotation direction of the rotating tub 4. The other configurations and operations use Embodiments 1 to 5. Only the differences will be described below.

  As shown in FIG. 10, when the rotation direction of the rotating tub 4 is A, the washing water flow A ′ becomes a turbulent flow in the drainage groove 3 part. At this time, since the discharge of the washing water from the drain port 17, that is, the suction of the washing water viewed from the pump 21, is inhibited, the rotation speed of the pump 21 is controlled to be lower than that in the case where the rotation direction is B. For example, the pump 21 normally rotates at a rotational speed of about 2500 rpm at a place of 3500 rpm. Thereby, even if the flow A ′ of the washing water hinders the suction of the washing water, the occurrence of air biting is suppressed. Furthermore, since the drive control of the pump 21 repeats constant intermittent drive, it becomes simpler.

  Note that each embodiment of the present invention can also be implemented in combination with other embodiments. Therefore, the combination of another embodiment or a part of another embodiment is also disclosed.

(Embodiment 7)
FIG. 11 is a time chart showing an operation during washing of the drum type washing machine in the seventh embodiment of the present invention. In the present embodiment, the pump 21 is driven differently depending on the rotation direction of the rotating tub 4. The other configurations use Embodiments 1 to 6. Only the differences will be described below.

  As shown in FIG. 11, when the rotation direction of the rotating tub 4 is A, the washing water flow A ′ becomes a turbulent flow in the drainage groove 3 part. For this reason, when the discharge of the washing water from the drain port 17, that is, the suction of the washing water viewed from the pump 21, is inhibited, the pump 21 is driven more times per unit time than when the rotation direction is B. Controlled to increase. At this time, the number of times of driving of the pump 21 is doubled in the rotational direction A compared to the rotational direction B, for example. When the pump 21 is driven many times per unit time, the number of stops per unit time is also increased. Therefore, while the pump 21 is stopped, the washing water containing water in the laundry is discharged from the laundry, so that the water level in the aquarium 2 becomes high. For this reason, if the pump 21 is driven many times, the water level is easily maintained, so that the water level does not decrease to the air biting water level of the pump 21 and air biting is suppressed.

  From the above, the total time (T2) that the pump 21 is driven when the rotation direction is A and the total time (T1) that the pump 21 is driven when the rotation direction is B are equal (T1 = T2). Also in this case, air biting is suppressed. Thereby, the supply amount of the washing water to the laundry in the rotating tub 4 becomes constant regardless of the rotation direction of the rotating tub 4, and it is effective in avoiding unevenness in washing efficiency.

  It should be noted that the total time for which the pump 21 is driven does not necessarily coincide with the rotation directions A and B.

  Note that each embodiment of the present invention can also be implemented in combination with other embodiments. Therefore, the combination of another embodiment or a part of another embodiment is also disclosed.

As described above, the drum type washing machine according to the present invention can suppress the occurrence of air biting of the circulation pump regardless of factors such as the rotation direction of the rotating tub, and is a drum type washing machine with excellent washing efficiency. Useful.

DESCRIPTION OF SYMBOLS 1 Case 2 Water tank 3 Drainage groove 3b, 3c Side wall 3d Extension rib 4 Rotating tank 5, 6 Opening part 7 Door body 8 Bellows 9 Motor 10 Rotating shaft center 11 Bottom part 12 Projection body 13 Small hole 14 Detergent container 15 Water supply valve 16 Water level detection means 17 Drain port 18 Drain path 19 Drain valve 20 Circulating water path 21 Pump 22 Nozzle water path 25 Inlet 32 Control means

Claims (7)

A water tank for storing washing water;
A rotating tank that is rotatably arranged in the water tank and has an opening on the front side;
A motor for driving the rotating tank;
A concave drainage groove formed in the lower part of the water tank;
A drain outlet provided at the bottom of the drainage groove and positioned laterally from the centerline of the drainage groove;
A circulation channel that communicates with the drain and circulates wash water in the water tank to the rotating tank;
A pump for feeding the wash water in the water tank to the circulation channel,
The drum-type laundry, wherein the pump has a shorter total driving time when the rotating tub rotates in the direction from the drain outlet side toward the center of the drain groove at the lower portion than when rotating reversely. Machine. The drum type washing machine according to claim 1, wherein the pump is controlled in accordance with a rotation direction of the rotary tub in a washing step. The pump has a motor with variable rotation speed,
The drum type washing machine according to claim 1 or 2, wherein the pump is controlled in accordance with a rotation direction of the rotating tub when the motor has a predetermined rotation speed or more. The drum-type washing machine according to claim 1, wherein an upper extending rib that covers the drain outlet is formed on a side wall of the drain groove on the drain outlet side. 5. The rotating tank according to claim 1, wherein the rotating tank rotates at a lower rotational speed when rotating in a direction from the drain outlet side toward the center of the drainage groove at a lower portion than when rotating reversely. The drum type washing machine according to claim 1. The rotation time of the rotating tub is shorter when rotating in the direction from the drain outlet side toward the center of the drainage groove at the lower part than when rotating reversely. A drum-type washing machine according to item 1. A water tank for storing washing water;
A rotating tank that is rotatably arranged in the water tank and has an opening on the front side;
A motor for driving the rotating tank;
A concave drainage groove formed in the lower part of the water tank;
A drain outlet provided at the bottom of the drainage groove and positioned laterally from the centerline of the drainage groove;
A circulation channel that communicates with the drain and circulates wash water in the water tank to the rotating tank;
A pump for feeding the wash water in the water tank to the circulation channel,
The pump has a motor with variable rotation speed,
The drum is characterized in that when the rotating tub rotates in the direction from the drain outlet side toward the center of the drainage groove at the lower part, the number of revolutions to be driven is lower than in the case of reverse rotation. Washing machine.