JPH10263272A - Washing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the generation of slip on the belt of belt transmission mechanism as much as possible. SOLUTION: When a dehydrating process is started, a controller starts a motor with torque in 100% (S1) and detects the presence/absence of slip generation on the belt of belt transmission mechanism based on the detection of rotation sensor (S2). When the slip occurs (S2;Y), electrification to the motor is stopped just for 0.5 sec (S3) and the torque is changed lower in 20%. Before the lapse of 5 sec with the current torque (S5;N), the presence/absence of slip on the belt is judged, in the case of no slip (S6;N), it is judged whether the torque is 100% or not and when it is not 100% (S7;N), processing is returned to S5. After the lapse of 5 sec with no slip in time state of the torque of motor less than 100% (S5;Y), on the other hand, the torque is changed higher in 10% (S9). When there is further slip on the belt during this operation (S6;Y), the electrification to the motor is stopped for 0.5 sec (S10) and the torque is changed lower in 10% (S11).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a washing machine for transmitting the rotational force of a motor to a dehydration tub or a pulsator via a belt transmission mechanism.

[0002]

For example, in a fully automatic washing machine, during a washing operation or a spin-drying operation, the rotational driving force of the motor is applied to a mechanism for driving the spin-drying tub and the pulsator. In general, the power is transmitted through a belt transmission mechanism. This belt transmission mechanism is configured by extending a V-belt between a motor-side pulley and a mechanism-side pulley.

However, due to the recent increase in the motor torque due to the increase in the washing capacity and the increase in the accuracy of the weight detection, the V-belt cannot be tightened and the tension is reduced. ing. For this reason, the slip of the V-belt is likely to occur particularly in the early stage of driving the motor. When such a slip of the V-belt occurs, not only does energy loss and abnormal sound occur, but also
The belt wears so much that slippage is more likely to occur.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a washing machine capable of minimizing occurrence of belt slippage of a belt transmission mechanism.

[0005]

According to a first aspect of the present invention, there is provided a washing machine for transmitting a rotational force of a motor to a dehydration tub or a pulsator via a belt transmission mechanism. Detecting means for detecting the occurrence of slip of the belt, and motor control means for temporarily reducing the torque of the motor when the slip of the belt is detected by the detecting means and thereafter returning to the original torque. Having.

According to this, if slippage occurs in the belt of the belt transmission mechanism when the motor is driven, the occurrence is detected by the detection means, and the motor is controlled by the motor control means so as to temporarily reduce the torque. . When a slip occurs, the rotation speed of the motor suddenly increases, but by reducing the motor torque, the rotation speed of the motor decreases and the frictional contact state of the belt is restored, so that the belt slip is quickly resolved. Will be done.

As a detecting means for detecting the slip of the belt, for example, if a rotation sensor originally provided for detecting the rotation speed of the motor is used, the rotation speed detected by the rotation sensor is detected. The rate of increase can be easily realized by comparing the rate of increase with a threshold value, and a simple configuration can be achieved without adding a separate sensor or the like.

In this case, at the start of driving, the number of rotations of the motor is rapidly increased from the stopped state of the belt, so that the slip of the belt is most likely to occur.
On the other hand, if the motor control means is configured to start driving the motor at a low torque and then increase the torque to a normal torque (the invention of claim 2), the motor is driven at a low torque at the start of the driving. Therefore, it is possible to effectively prevent the belt from slipping at the initial stage of driving the motor.

As described above, even when the slip of the belt occurs, even if the slip is immediately eliminated, at least the time during which the slip occurs is a loss of time. It is also important that they do not occur. However, if the washing operation is performed under the same conditions as when the belt slip occurred in the past, it is conceivable that the belt slip similarly occurs during the current operation.

In view of the above, there is provided means for predicting and storing a torque control pattern in which no slip occurs based on the relationship between the motor torque fluctuation with the passage of time in the past washing operation and occurrence of slip, and providing a motor control means. To
It can be configured to execute the torque control of the motor based on the torque control pattern (the invention of claim 3).

According to this, a torque control pattern which does not cause the belt slip is predicted based on what kind of torque fluctuation caused the belt slip in the past, and based on the torque control pattern. By controlling the motor, it is possible to execute a washing operation that minimizes belt slippage.

Further, at this time, since the humidity and temperature during the washing operation affect the ease of slipping of the belt, a torque control pattern that does not cause a slip is considered in consideration of the humidity or temperature during the washing operation. If it is configured to predict (the invention of claim 4), it is possible to more precisely predict a torque control pattern that does not cause slip of the belt.

According to a fifth aspect of the present invention, there is provided a washing machine for detecting a belt slip of the belt transmission mechanism, and energizing the motor when the belt slip is detected by the detecting means. And a motor control means for temporarily shutting off. According to this, when the slip of the belt occurs, the power supply to the motor is temporarily interrupted, so that the slip of the belt is also quickly eliminated.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments in which the present invention is applied to a fully automatic washing machine will be described below with reference to the drawings. (1) First Embodiment First, a first embodiment (corresponding to claim 1) of the present invention will be described with reference to FIGS.

FIG. 2 schematically shows the entire structure of the washing machine according to the present embodiment. Here, an outer box 1 having a rectangular box shape is shown.
Inside, an outer tub 2 is provided via an elastic suspension mechanism 3. A dehydration tub 4 also serving as a washing tub is rotatably provided in the outer tub 2.
A pulsator 5 for generating a water flow is provided. A motor 6 composed of, for example, an induction motor is provided at the outer bottom of the outer tub 2, and the rotational force of the motor 6 is transmitted via a belt transmission mechanism 7 to rotate the dewatering tub 4 and the pulsator 5. A driving mechanism 8 for driving is provided.

The belt transmission mechanism 7 has a belt (V-belt) 7c extending between a pulley 7a on the motor 6 side and a pulley 7b on the drive mechanism section 8 side. At this time, the belt 7c is stretched with a relatively low tension. Further, the drive mechanism 8 includes a clutch mechanism, a speed reduction mechanism, a brake mechanism, and the like. As a result, the rotational force of the motor 6 is transmitted to the drive mechanism 8 via the belt transmission mechanism 7, and during the washing and rinsing steps, the pulsator 5 is rotated forward and reverse. In the process of dehydration (and dehydration rinsing)
The dewatering tub 4 is rotated at a high speed in one direction together with the pulsator 5.

The rotating shaft portion of the motor 6 includes:
As shown in FIG. 3, a rotation sensor 9 is provided as rotation number detecting means for detecting the rotation number of the motor 6. Although not shown in detail, the rotation sensor 9 is configured by, for example, providing a plurality of magnetic poles around a rotation axis of the motor 6 and arranging a Hall element in the vicinity thereof, and a pulse signal (corresponding to the rotation speed of the motor 6). (For example, 8 pieces per rotation)
Is output.

A drain 10 for draining the water from the dewatering tank 4 is provided at the bottom of the outer tub 2, and a drain hose 12 is connected to the drain 10 via a drain valve 11. I have. Further, a drain 13 for draining water from the outer tub 2 is provided at the bottom of the outer tub 2.
Reference numeral 3 is connected to the drain hose 12 via a drain passage (not shown).

On the other hand, a balance ring 14 is mounted on the upper end of the dewatering tub 14, and a dewatering hole 15 for discharging water from the dewatering tub 14 through the balance ring 14 during dewatering. Is provided. A substantially ring-shaped tub cover 16 is provided at the upper end of the outer tub 2, and the tub cover 16 is provided with an inner lid 17 for opening and closing the opening. The inner lid 17 has a concave portion 18 located on the rear side and having a number of water injection holes 18a.

Further, a top cover 19 is provided at the upper end of the outer box 1. The top cover 19 has a laundry entrance (not shown) and a lid 20 for opening and closing the entrance. A water supply mechanism including a water supply valve 21 and a water injection case 22 having a detergent storage section is provided at a rear side portion of the top cover 19. With this, the water supply valve 21
Water from water supply source (tap water or bath water)
The water is supplied into the concave portion 18 of the inner lid 17 through the water injection case 22, and the water is showered from the water injection hole 18a and supplied to the dewatering tank 4.

On the front side of the top cover 19,
An operation panel (not shown) is provided on the upper surface, and a control box 23 is provided on the back surface thereof. In the control box 23, a control device 24 mainly composed of a microcomputer is provided, and a humidity sensor 25 and a temperature sensor 26 are provided.

An operation signal from the operation panel, a detection signal of the rotation sensor 9, a signal from the humidity sensor 25 and the temperature sensor 26, and a signal from a water level sensor (not shown) are input to the control device 24. It has become.
The control device 24 controls the motor 6 via a drive circuit (not shown) based on those input signals and a control program stored in advance, and displays the water supply valve 21, the drain valve 11, and the operation panel. The washing operation is executed by controlling the sections and the like. At this time,
The control device 24 can control the output torque of the motor 6 by freely changing the voltage applied to the motor 6.

The control device 24 detects the occurrence of slippage of the belt 7c of the belt transmission mechanism 7 based on the detection of the rotation sensor 9 in the dewatering process, the washing process, and the like, by the software configuration. It is supposed to. Therefore, a detecting means is constituted by the control device 24, the rotation sensor 9, and the like.

Specifically, as shown in FIG. 3, for example, in the initial state of the dehydration process, if there is no slip and the condition is normal, the rate of increase in the rotation speed of the motor 6 is about 70 rpm / sec ( The inclination shown by a in FIG. 3). On the other hand, the belt 7c
When the slip occurs, as shown by b in FIG. 3, the rotation speed of the motor 6 rises at a stretch, and the rate of increase is about 1400 rpm / sec. The control device 24 reads the rotation speed of the motor 6 detected by the rotation sensor 9 every 0.1 seconds, for example, to determine the change rate of the rotation speed, and determines the change rate as a threshold (for example, 140 rpm / second; FIG. , The slope of the belt 7c is determined to have occurred if the threshold value is exceeded.

The controller 24 controls the motor 6 to start up to a predetermined rotation speed (for example, 1400 rpm) at a torque of 100% in a dehydration process, for example. Then, as will be described in detail in the following flow chart description, this motor 6
When the slip is detected by the slip detection at the time of starting, the torque of the motor 6 is temporarily reduced, and thereafter, the original torque is returned over time. Therefore, the motor control means is constituted by the control device 24 and the like.

Next, the operation of the above configuration will be described with reference to FIGS. For example, in the dehydration process,
The control device 24 controls the motor 6 (and eventually the dewatering tub 4) to start up to a predetermined rotation speed and thereafter maintain the rotation speed. At this time, the belt 7 of the belt transmission mechanism 7
Due to the reduction in tension of c, the slip of the belt 7c tends to occur particularly in the early stage of the operation of the motor 6. Thus, in the present embodiment, when the motor 6 is started, torque control as shown in the flowchart of FIG. 1 is executed.

That is, when the dewatering process is started, the motor 6
Is started with 100% torque (step S1). First, in step S2, the belt 7c at the time of starting is
Is determined. This determination is made by comparing the rate of change (increase rate) of the number of revolutions of the motor 6 for 0.1 second from the start with the threshold value, as described above. Here, when it is determined that the slip has occurred (Yes in step S2), the power supply to the motor 6 is stopped for 0.5 seconds (step S3), and thereafter, the torque of the motor 6 is reduced by 20%. Torque (80% at first time
) (Step S4), and then returns to step S2.

If it is determined in step S2 that there is no slip (No), it is determined in step S5 whether a predetermined time, for example, 5 seconds, has elapsed with the current torque. (No), next step S
At 6, it is determined whether or not the belt 7c has slipped. If there is no slip (No), it is determined in the next step S7 whether the torque is 100%. If not (No), the process returns to step S5 and repeats the same processing. Even if it is 100% (Ye in step S7)
s) Until the rotation speed of the motor 6 reaches the predetermined rotation speed (No in step S8), the processing from step S6 is repeated.

On the other hand, the torque of the motor 6 is 100%
If a predetermined time, for example, 5 seconds has elapsed with the torque without slipping (No in step S6) in a state where the torque is lowered (Yes in step S5), the torque is changed to 10% higher in step S9, Then step S
Proceed to 6. Further, when the slip of the belt 7c further occurs during such control (step S6).
Is Yes), the energization of the motor 6 is stopped for 0.5 seconds (step S10), and then the torque of the motor 6 is reduced to 10
The torque is changed to a% lower torque (step S11), and the process returns to step S5.

By controlling the torque of the motor 6 as described above,
When a slip occurs in the belt 7c of the belt transmission mechanism 7, the power supply to the motor 6 is stopped for 0.5 seconds, and the motor 6 is controlled so that the torque is reduced in a state where the rotation speed of the motor 6 is reduced. . By stopping the motor 6 and decreasing the torque, the frictional contact state of the belt 7a is recovered, and the slip of the belt 7c is promptly eliminated.

FIG. 4 shows an example of how the number of revolutions of the motor 6 changes with time as a result of executing the above torque control. Here, the slip of the belt 7c occurs when the motor 6 is started (100% torque), and the torque is changed to 80% after stopping for 0.5 second.
The torque has been reduced to 0%. At 60% torque, no slip occurs, and after 5 seconds, the torque is increased to 70% torque, and further increased to 80% torque and then to 90% torque. The belt 7c did not slip until 80% torque, but slip occurred at 90% torque, and was reduced to 80% torque after a temporary stop, and then increased to 100% torque without slip. I have.

As described above, according to the present embodiment, the presence or absence of occurrence of slip of the belt 7c of the belt transmission mechanism 7 is detected based on the detection of the rotation sensor 9, and when the slip occurs, the torque of the motor 6 is reduced. Since such control is performed, occurrence of slip of the belt 7c can be suppressed as much as possible.

In this case, if the torque of the motor 6 is controlled sufficiently low in advance, the occurrence of a slip can be avoided, but the efficiency is inferior and the start-up time of the motor 6 becomes longer. On the other hand, in the present embodiment, the torque of the motor 6 can always be high near the limit of occurrence of slip, so that the rotation speed of the motor 6 can be increased efficiently, and the motor 6 is rotated at a predetermined rotation speed. The time required to start up to a number can be sufficiently reduced.

Further, in the present embodiment, in consideration of the situation in which the slip of the belt 7c is most likely to occur when the motor 6 is started, the amount of reduction in torque when the slip occurs immediately after the start (step S4) is determined. Since it is larger than that in the case where a slip occurs during the process (step S11), it is more effective in preventing the occurrence of a slip again, and in shortening the start-up time.

(2) Second Embodiment FIG. 5 shows a second embodiment (corresponding to claim 2) of the present invention. This embodiment differs from the first embodiment in the software configuration of the control device 24. Therefore, since the hardware configuration of the washing machine is the same as that of the first embodiment, a new illustration and detailed description are omitted, and the same reference numerals are used below.

In this embodiment, the control device 24 starts driving the motor 6 at a low torque, for example, 5% torque in this case at the start of the dewatering process, and thereafter, the slip of the belt 7c of the belt transmission mechanism 7 is generated. While monitoring the presence / absence, the torque is gradually increased to the normal torque (100% torque). The control procedure at that time is shown in the flowchart of FIG.

That is, when the dewatering process is started, the motor 6
Are started at a low torque of 5% (step S21). Then, in the next step S22, it is determined whether or not the belt 7c has slipped. If there is no slip (No), it is determined in the next step S23 whether the torque is 100%, and if it does not reach 100% (No), the torque of the motor 6 is changed to 5% higher torque. Is performed (step S24).

In this way, the torque of the motor 6 becomes 10
Although the torque is increased stepwise to 0% torque, if the belt 7c slips during that time (step S22).
, Yes), the power supply to the motor 6 is stopped for 0.5 seconds (step S25), and the torque of the motor 6 is changed to a torque lower by 5% (step S26).

Then, in the next step S27, it is determined whether or not a predetermined time, for example, 5 seconds, has elapsed with the current torque. If not (No), the next step S27 is executed.
At 28, it is determined whether the belt 7c has slipped. If there is no slip (No), it is determined in the next step S29 whether or not the torque is 100%. If not (No), the process returns to step S27 and repeats the same processing. In addition, even if it is 100% (Yes in step S29), the processing from step S28 is repeated until the rotation number of the motor 6 reaches the predetermined rotation number (No in step S30). The process also proceeds to step S30 when the torque is 100% in step S23.

On the other hand, the torque of the motor 6 is 100%
If the torque is reduced in a state of less than the predetermined value, and if a predetermined time, for example, 5 seconds has elapsed with the torque (Yes in step S27), the torque is changed to 10% higher in step S31, and then the process proceeds to step S28. . In addition, during such control, when the slip of the belt 7c further occurs (Yes in step S28), 0.5
Power supply to the motor 6 is stopped for a second (step S32),
Then, the torque of the motor 6 is changed to 10% lower torque (step S33), and the process returns to step S27.

By controlling the torque of the motor 6 as described above,
When a slip occurs in the belt 7c of the belt transmission mechanism 7, the power supply to the motor 6 is stopped for 0.5 seconds, and the motor 6 is controlled so as to reduce the torque in a state where the rotation speed of the motor 6 is reduced. . By stopping the motor 6 and decreasing the torque, the frictional contact state of the belt 7a is restored, and the slip of the belt 7c is quickly eliminated. As long as the belt 7c does not slip, the torque of the motor 6 is sequentially increased, so that the rotation speed of the motor 6 can be increased in a short time.

Therefore, also in this embodiment, the first
Similarly to the embodiment, the occurrence of slip of the belt 7c can be suppressed as much as possible, the rotation speed of the motor 6 can be increased efficiently, and the time required for the motor 6 to start up to the predetermined rotation speed can be obtained. Can be sufficiently reduced.
In addition to this, when the driving of the motor 6 is started, the slip of the belt 7c of the belt transmission mechanism 7 is most likely to occur. In the present embodiment, the driving of the motor 6 is started at a low torque (5% torque). With this configuration, it is possible to effectively prevent the belt from slipping at the initial stage of driving the motor.

(3) Third and Fourth Embodiment FIGS. 6 to 8 show a third embodiment of the present invention.
4). This embodiment is different from the first and second embodiments in that the control device 24 controls the relationship between the torque fluctuation of the motor 6 and the occurrence of slip with the lapse of time in the past washing operation (operation result). From the storage means (R
AM, rewritable ROM, etc.), and unless the slip of the belt 7c of the belt transmission mechanism 7 occurs, the torque control of the motor 6 is performed based on the torque control pattern. ing.

Further, in this embodiment, for example, five levels of humidity rank are provided, and a torque control pattern is set (predicted) for each humidity rank and stored. Therefore,
The torque of the motor 6 is controlled based on the torque control pattern of the humidity rank corresponding to the current humidity detected by the humidity sensor 25.

More specifically, it is assumed that the past operation result is as shown in FIG. 4 shown in the first embodiment. From this operation result, by removing the torque at the time when the belt 7c slips, a torque control pattern with no slip is predicted. In this torque control pattern, for example, the torque of the motor 6 in increments of 10% is
Each is set for how many seconds to continue. The torque control pattern shown in FIG. 6 is predicted from the operation results in FIG.

That is, first, if the motor 6 is started at 60% torque, it can be predicted that no slippage of the belt 7c will occur (it can be predicted that slippage will occur at 100% or 80% torque). Also. Even if the 60% torque is continuously increased to 70% for 5 seconds, it can be predicted that no slip will occur, and the slip is continued for 5 seconds to 80%.
It can be predicted that no slip will occur even if the torque is increased.

Then, instead of applying 80% torque for 5 seconds,
By increasing the torque to 90% after continuing for 10 seconds, it can be predicted that no slip will occur (the operation results in FIG. 4 indicate that there is a possibility that a slip may occur if the 80% torque is 5 seconds). ). 90% torque 5
Even if the torque is continuously increased to 100% for seconds, it can be predicted that no slip will occur, and thereafter it can be predicted that no slip will occur at 100% torque.

As shown in FIG. 7, such a torque control pattern is set for each of five levels of humidity. For example, if the operation result of FIG. 4 is obtained when the humidity is 50%, that is, at the humidity rank 3, the torque control pattern in FIG. 6 becomes the torque control pattern at the humidity rank 3, and when the operation of the washing machine is started, Humidity sensor 25
If the detected humidity falls into the humidity rank 3, the motor 6 is controlled by the torque control pattern of the humidity rank 3.

Here, when a slip occurs due to the control based on the stored torque control pattern, the same control as in the first embodiment (step S in FIG. 1) is performed.
5 to S11), and a torque control pattern with no slip is predicted again from the operation result at that time and is set (updated).

Further, in this embodiment, the setting and updating of the torque control pattern are performed for all the humidity ranks lower than the humidity rank at that time. This is due to the fact that the lower the humidity, the more likely the slip occurs. In the state where there is no operation result at the beginning of use (when shipped from the factory), all the torque control patterns are set to 100% torque. Therefore, the same control as in the first embodiment (FIG. 1) is performed. Will be done.

The above control procedure is as shown in the flowchart of FIG. That is, when the dehydration process is started, first, humidity detection is performed by the humidity sensor 25 (step S41), and a torque control pattern of a humidity rank corresponding to the humidity is read from the storage unit (step S41).
42). Then, energization control of the motor 6 is performed according to the read torque control pattern (step S4).
3). In the example shown in FIG.
The motor 6 is controlled in the following order:% torque is 5 seconds, 80% torque is 10 seconds, 90% torque is 5 seconds, and then 100% torque.

During this control, the presence or absence of slippage of the belt 7c is constantly monitored (step S44). Unless slippage occurs (No),
Until the start-up of the motor 6 is completed (step S4
6), the control according to the torque control pattern is continuously performed (step S45).

On the other hand, if the occurrence of slip is detected somewhere at the time of startup (Ye in step S44)
s) The energization of the motor 6 is stopped for 0.5 seconds (step S47), and the torque of the motor 6 is changed to 10% lower torque (step S48). Thereafter, steps S5 to S5 in the flowchart of FIG. 1 of the first embodiment are performed.
Control similar to S11 is performed (step S11).
49), and the description is omitted because it is redundant.

When such control (start-up of the motor 6) is completed, a new torque control pattern with no slip is predicted in step S50 from the operation result at that time. In this case, the torque control pattern predicted from the operation result at that time should be different from the previous torque control pattern (see FIG. 6). Then, in step S51, the newly predicted and set torque control pattern is stored (updated) in the storage means. Here, all the humidity ranks equal to or lower than the humidity rank corresponding to the humidity at the time of the operation are stored. , And a new torque control pattern.

According to such an embodiment, a torque control pattern that prevents the belt 7c from slipping is predicted based on what kind of torque fluctuation has caused the belt 7c to slip in the past. By controlling the motor 6 according to the above, it is possible to execute a washing operation in which the slip of the belt 7c is minimized. When the slip of the belt 7c occurs, it is needless to say that the slip can be quickly eliminated.

Further, in this embodiment, in consideration of the fact that the humidity during the washing operation affects the ease of slipping of the belt 7c (the lower the humidity, the easier the slipping), the torque control is performed for each humidity rank. Since the pattern is set, a torque control pattern that does not cause slippage of the belt 7c can be precisely predicted, and appropriate control according to the humidity during the washing operation can be performed. It becomes.

FIG. 9 shows a fourth embodiment of the present invention. In this embodiment, the temperature during the washing operation is also controlled by the belt 7c.
In consideration of the influence on the ease of slipping (the lower the temperature, the easier the slipping), for example, in addition to five humidity ranks, four temperature ranks are provided, and for each humidity rank and temperature rank ( The torque control pattern is set (predicted) and stored (at 20 stages in total).

In this case, in the flowchart of FIG. 8, in step S41, in addition to the humidity detection, the temperature detection by the temperature sensor 26 is also performed.
At 2, the torque control patterns corresponding to both the ranks of humidity and temperature are read. Then, in step S51, the newly predicted and set torque control pattern is stored (updated) in the storage means. Humidity and temperature corresponding to the humidity and temperature during the operation, and humidity and temperature below the temperature rank are used. All of the ranks will be rewritten with the new torque control pattern. For example, if the current rank is
When the humidity rank is 3 and the temperature rank is 3, FIG.
The torque control patterns of all ranks indicated by * are rewritten with the same new one.

According to this configuration, as in the third embodiment, in addition to obtaining the effect, it is possible to more precisely predict a torque control pattern that does not cause slippage of the belt 7c. This makes it possible to perform appropriate control according to the humidity and temperature during the washing operation.

(4) Fifth Embodiment Finally, FIG. 10 shows a fifth embodiment (corresponding to claim 5) of the present invention. In this embodiment, the presence or absence of slippage of the belt 7c of the belt transmission mechanism 7 is detected based on the detection of the rotation sensor 9, as in the first embodiment. here,
The control device 24 does not control the torque of the motor 6, and when the occurrence of slip of the belt 7c is detected,
The motor 6 is configured to be turned off only for a fixed time (for example, 0.5 seconds).

FIG. 10 shows the state at the start of the dehydration process.
It shows an example of a change in the number of revolutions of the motor 6 with the passage of time when the belt 7c slips, where b indicates no control and d indicates the control of the present embodiment. ing. In this case, when the slip of the belt 7c occurs, the power supply to the motor 6 is temporarily interrupted. Therefore, the rotation speed of the motor 6 is reduced, and the frictional contact state of the belt 7c is recovered. The slip is quickly eliminated. Further, in the present embodiment, since it is not necessary to perform the torque control, it is possible to obtain an advantage that the configuration is simplified as compared with the first embodiment.

In each of the above-described embodiments, the slip of the belt 7c is eliminated. However, the belt 7c becomes loose due to long-term use, and the motor 6 is driven with any small torque. However, it is also conceivable that the dehydration tank 4 cannot be driven to rotate. Therefore, for example, the dewatering tank 4
If the predetermined number of rotations is not reached even after a predetermined time has elapsed from the start of the stroke, it is determined that the slack of the belt 7c has exceeded an allowable range, and the belt 7c may be configured to notify that repair is required.

In the above-described embodiment, the torque is made variable by controlling the voltage of the induction motor 6. However, the torque can be made variable by controlling the frequency. Various controllable motors can be employed. In the above-described embodiment, the dehydration process has been described as an example. However, the detection of the slip of the belt 7c and the motor control can be similarly performed in the washing process and the rinsing process.

In addition, the present invention is not limited to the above-described embodiments, and can be applied to a washing machine having a plurality of motors, such as a two-tub washing machine. Only one may be stored regardless of the temperature or temperature. Further, various methods may be considered as prediction of a torque control pattern without occurrence of belt slip. It can be changed and implemented.

[0065]

As is apparent from the above description, according to the washing machine of the present invention, the rotation force of the motor is transmitted to the dewatering tub or the pulsator via the belt transmission mechanism. The belt transmission mechanism includes detection means for detecting occurrence of slip of the belt, and motor control means for temporarily reducing the motor torque and then returning to the original torque when the detection of the belt slip is detected. This has an excellent practical effect of minimizing the occurrence of belt slippage of the belt transmission mechanism.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of the present invention, and is a flowchart showing a control procedure of a motor at the start of a dehydration stroke.

FIG. 2 is a longitudinal sectional side view showing the entire configuration of the washing machine.

FIG. 3 is a diagram showing a state of a change in the number of rotations of a motor in a normal state and when a slip occurs.

FIG. 4 is a diagram showing an example of a change in the number of revolutions due to torque control of the motor.

FIG. 5 is a view corresponding to FIG. 1 showing a second embodiment of the present invention.

FIG. 6 is a view showing a third embodiment of the present invention and showing an example of a torque fluctuation pattern;

FIG. 7 is a diagram showing a relationship between humidity and humidity rank.

FIG. 8 is a diagram corresponding to FIG. 1;

FIG. 9 shows a fourth embodiment of the present invention and is a diagram showing a relationship between humidity, temperature, and rank.

FIG. 10 is a view showing a fifth embodiment of the present invention, and showing an example of a change in the number of revolutions due to power cutoff control of the motor.

[Explanation of symbols]

In the drawing, 4 is a dewatering tank, 5 is a pulsator, 6 is a motor, 7
Is a belt transmission mechanism, 7c is a belt, 8 is a drive mechanism, 9
Denotes a rotation sensor, 24 denotes a control device (detection means, motor control means), 25 denotes a humidity sensor, and 26 denotes a temperature sensor.

Claims (5)

[Claims] An apparatus for transmitting the rotational force of a motor to a dewatering tub or a pulsator via a belt transmission mechanism, wherein: a detection means for detecting occurrence of a slip of the belt of the belt transmission mechanism; A washing machine comprising: a motor control means for temporarily reducing the torque of the motor when belt slip is detected, and thereafter returning the torque to the original torque. 2. The washing machine according to claim 1, wherein the motor control means is configured to start driving the motor at a low torque and thereafter increase the torque to a normal torque. 3. A means for predicting and storing a torque control pattern with no occurrence of slip based on a relationship between a change in torque of the motor with the passage of time during a past washing operation and occurrence of slip, wherein the motor control means comprises: The washing machine according to claim 1 or 2, wherein torque control of the motor is performed based on the torque control pattern. 4. The washing machine according to claim 3, wherein the torque control pattern without slip is set for each rank of humidity or temperature during the washing operation. 5. A device for transmitting a rotational force of a motor to a dehydration tub or a pulsator via a belt transmission mechanism, wherein: a detection means for detecting occurrence of a slip of the belt of the belt transmission mechanism; A washing machine comprising: a motor control unit that temporarily shuts off the power supply to the motor when belt slippage is detected.