JP2001062189A - Washing machine, and washing machine vibration detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of an abnormal vibration when eccentric load is increased by drying irregularity as drying advances while the balance is being adjusted in a drum before starting drying. SOLUTION: In this washing machine, a vibration detecting switch comprising a casing having an inclined surface in a rolling direction of an outer tub, a steel ball to roll on the inclined surface, and a switch to be close when the steel ball rises to a specified position is installed at an upper part of the outer tub. Eccentricity quantity is detected at rotation speed of 130 rpm (S2), and when the eccentricity quantity is less than a tolerable value, the speed is increased up to 500 rpm (S3, S5). After slightly conducting drying at this rotation speed, it is determined if the vibration detect switch is put on or not (S6, S7), and in the case of on, the highest drying rotation speed is set at 500 rpm (S8). Otherwise, the speed is increased up to 700 rpm, and when the vibration detecting switch is put on in this process, the highest drying rotation speed is set at 700 rpm (S11), and when it is not turned on, it is set at 1,000 rpm (S13).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a washing machine and a vibration detecting device for detecting a vibration of a washing and dewatering tub in the washing machine.

[0002]

2. Description of the Related Art In a drum type washing machine provided with a drum which rotates about a horizontally extending rotating shaft, if the laundry is unbalancedly distributed around the rotating shaft during the spin-drying operation, the drum or the outer tub may be disturbed. Vibrates greatly and abnormal noise is generated. Therefore,
In a general drum-type washing machine, a weight is attached around an outer tub in which a drum is installed in order to suppress abnormal vibration.
For this reason, the conventional drum type washing machine is very heavy, the installation place is limited, and movement and transportation are difficult.

[0003] In order to solve such a problem, conventionally, before dewatering is started (that is, before the rotation speed of the drum is increased to a rotation speed at which dehydration is substantially performed), the inner peripheral wall of the drum is depressed. An operation control has been proposed in which laundry is appropriately distributed and the balance is adjusted so as to reduce the eccentric load, and after the appropriate balance is adjusted, the rotation speed is increased to a high spin-dry speed. . For example, the present applicant has proposed various methods for performing an appropriate balance adjustment before starting dehydration in an apparatus described in Japanese Patent Application Laid-Open No. H11-76686.

[0004]

Considering the method of washing in ordinary households, washing is often carried out in a state in which clothing made of synthetic fibers such as polyester and clothing made of cotton are mixed. Water escapes relatively quickly with synthetic fibers, whereas water does not easily escape with cotton. For this reason, in a state where clothes having greatly different easiness of dehydration are mixed as described above, even if the balance adjustment is appropriately performed immediately before the start of dehydration, some parts of the garment are dehydrated as dehydration proceeds. The eccentric load increases during the dehydration due to the drainage of water only from the laundry first, which may cause large vibration and noise.

[0005] The present invention has been made in view of such a point, and an object thereof is to reliably prevent abnormal vibration and noise from being generated even when an eccentric load increases during dehydration. An object of the present invention is to provide a washing machine capable of performing dehydration by using a washing machine. It is another object of the present invention to provide a vibration detection device capable of quickly and reliably detecting vibration during centrifugal dehydration in a washing machine.

[0006]

Means for Solving the Problems and Embodiments of the Invention A washing machine according to the present invention, which has been made to solve the above-mentioned problems, has a washing machine inside an outer tub swingably disposed inside a machine frame. A dewatering tub is rotatably provided, and the washing and dewatering tub is rotated at a high speed to perform centrifugal dehydration of the laundry housed in the dewatering tub. B) speed detecting means for detecting the rotation speed of the washing and dewatering tub, c) rotating speed of the washing and dewatering tub such that the laundry can be dehydrated. Operation control means for determining the maximum spinning rotation speed according to the rotation speed at the time when a vibration equal to or greater than a predetermined value is detected, using the vibration detection means and the speed detection means. I have.

That is, in the process of increasing the rotation speed of the washing and dewatering tub, generally, the higher the rotation speed, the faster the speed of dehydration. When the eccentric load increases due to factors such as non-uniformity of dehydration as the dehydration progresses, the vibration of the outer tub increases. Therefore, the operation control means determines that the increase in the eccentric load increases as the rotation speed decreases at the time when the vibration equal to or more than the predetermined value is detected by the vibration detection means, and suppresses the maximum dewatering rotation speed. Thereby, even if dehydration progresses and the eccentric load further increases, the occurrence of abnormal vibration can be avoided because the rotation speed is relatively low. On the other hand, when the eccentric load does not increase during the dehydration operation or when the increase is small, the maximum dehydration rotation speed is set to be high, so that dehydration is performed with higher dehydration efficiency.

Further, in the washing machine of the present invention, the operation control means c) includes: c1) whether or not a vibration equal to or greater than a predetermined value is detected by the vibration detecting means when the washing / dewatering tub is rotating at a predetermined rotation speed. First determining means for determining whether or not; c2) when the first determining means determines that vibrations equal to or greater than a predetermined value have not been detected, gradually increasing the rotation speed from the predetermined rotation speed; In the process, a second determining means for examining a rotation speed at a time when a vibration equal to or more than a predetermined value is detected by the vibration detecting means; c3) a result of the determination by the first determining means and obtained by the second determining means. Speed determining means for determining the maximum spinning speed according to the rotation speed.

That is, first, the rotation speed of the washing and dewatering tub is increased to a predetermined rotation speed, and at that time, the first determination means performs vibration detection by the vibration detection means. Up to immediately before the detection of the vibration, the laundry contained in the washing and dewatering tub is in a lightly dehydrated state. The speed determining means determines that, when vibrations equal to or more than a predetermined value are detected at this time, the rotation speed is further increased and full-scale dehydration is likely to cause abnormal vibration. The maximum rotation speed is set to the predetermined rotation speed to perform dehydration. On the other hand, if no vibration equal to or more than a predetermined value is detected at the predetermined rotation speed, the rotation speed is further gradually increased. When the eccentric load increases due to the progress of dehydration in the process of increasing the rotation speed, the vibration amplitude of the outer tub increases. Therefore, the second determination means obtains the rotation speed at the time when the vibration equal to or more than a predetermined value is detected by the vibration detection means. The speed determining means determines that the lower the rotation speed is, the higher the risk of abnormal vibration is, and sets a lower maximum dehydration rotation speed.

[0010] In the washing machine according to the present invention, the vibration detecting means may include a surface which is vertically inclined in a direction in which the outer tub rolls, and a spherical body which is arranged to roll on the inclined surface. When,
Position detecting means for detecting that the spherical body has reached the predetermined position by ascending on the inclined surface.

When the outer tank rolls and vibrates, a force acts on the spherical body in a horizontal direction, and the spherical body rolls on the inclined surface according to the force. As the acceleration of vibration increases, the spherical body rises to a higher position. Therefore, when the vibration reaches a certain acceleration, the spherical body reaches a predetermined position, which is detected by the position detecting means. Here, as an example, the position detecting means may be a mechanical switch that is pressed or closed by the spherical body when the spherical body reaches a predetermined position. As another example, a method of optically or magnetically detecting that the spherical body has reached a predetermined position in a non-contact manner can be used.

According to such a vibration detecting means, the vibration of the outer tub can be detected reliably and quickly.
In the washing machine provided with the vibration detecting means, the occurrence of abnormal vibration during dehydration can be reliably avoided.

Further, the washing machine according to the present invention may be a drum type washing machine having a drum in which the washing and dewatering tub is rotated around a substantially horizontal axis. It is preferable to be installed above the outer tank in which the drum is installed.

Further, the vibration detecting device for a washing machine according to the present invention has the same structure as the above-mentioned vibration detecting means, and comprises: a) a surface which is vertically inclined in the lateral direction of the outer tub, and b) the inclined surface. A spherical body arranged to roll on the top, and c) position detecting means for detecting that the spherical body has climbed an inclined surface and reached a predetermined position.

[0015]

According to the washing machine of the present invention, the vibration of the outer tub caused by the progress of dehydration is grasped, and if the possibility of occurrence of abnormal vibration is high, the dehydration is performed at a relatively low rotation speed. Is completed. Therefore, for example, even if the dehydration is performed in a state in which laundry having a large difference in ease of dehydration is mixed, and the eccentric load increases with the progress of dehydration,
It is possible to reliably avoid occurrence of abnormal vibration and abnormal noise, and it is possible to proceed with dehydration without delay.
On the other hand, when there is no fear of abnormal vibration as the dehydration progresses, dehydration can be completed at a higher rotation speed, so that a high dehydration effect can be obtained.

Further, according to the vibration detecting device for a washing machine according to the present invention, the lateral vibration of the outer tub can be detected reliably and without time delay, so that the above-mentioned abnormal vibration can be avoided. Can be achieved.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A drum type washing machine according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side sectional view of the drum type washing machine, and FIG. 2 is a sectional view taken along the line aa 'in FIG. First, the configuration of the drum type washing machine of the present embodiment will be described with reference to FIGS.

An outer tub 2 is suspended by a spring 3 and a damper 4 inside the machine casing 1, and a drum 5 for containing laundry is supported by a main shaft 8 inside the outer tub 2. A door 7 for opening and closing the front opening of the outer tub 2 is provided on the front of the machine casing 1, and the laundry is stored inside the drum 5 by opening the door 7. A large number of water holes 6 are provided in the peripheral wall of the drum 5, and water supplied to the outer tub 2 flows into the drum 5 through the water holes 6, and conversely, from the laundry in the drum 5. The dehydrated water is scattered to the outer tub 2 through the water holes 6. On the inner circumference of the drum 5, a baffle 9 for scraping up the laundry with the rotation is provided at a predetermined rotation angle. The main shaft 8 is held by a bearing 10 mounted on the outer tub 2, and a main pulley 11 is attached to a tip of the main shaft 8. A motor 12 is arranged on the lower surface of the outer tub 2, and the rotational driving force of the motor 12 is transmitted to the main pulley 11 via a motor pulley 13 and a V-belt 14. In this embodiment, a DC brushless motor is used as the motor 12.

The ring body of the main pulley 11 is provided with one opening on the circumference, and a rotation sensor 19 composed of a light emitting unit and a light receiving unit is arranged on both sides of the ring body. The rotation sensor 19 detects that the light emitted from the light emitting unit
During one rotation period, the light passes through the opening only once and reaches the light receiving section, and outputs a detection signal (rotation marker) synchronized with the rotation of the drum 5 based on the light receiving signal. Instead of using the optical rotation sensor 19, a magnet is mounted on the drum 5 side, and a reed switch that opens and closes by magnetic force is provided on the machine frame 1 or the outer tub 2 side, and conducts only once during one drum rotation period. The detection signal may be output by a reed switch.

The water supply pipe 15 connected to the external tap is
It is connected to the outer tank 2 via a water supply valve 16. When the water supply valve 16 is opened, water is supplied to the outer tub 2 through the water supply pipe 15. On the other hand, a drainage pump 18 is provided in a drainage pipe 17 connected to the bottom of the outer tub 2, and water accumulated in the outer tub 2 is discharged to the outside by driving the drainage pump 18.

A vibration detection switch 20 for detecting vibration of the outer tub 2 is mounted on the upper portion of the outer tub 2.
FIG. 9 is a longitudinal sectional view showing the structure of the vibration detection switch 20. The vibration detection switch 20 is provided with a casing 21 which is attached to be inclined at a predetermined inclination angle α in the circumferential direction of the peripheral surface of the outer tub 2, and a lid fixed by screws 23 so as to close the upper surface of the casing 21. 22 and a steel ball 24 rotatably housed on an inclined surface 21 a on the bottom surface of the casing 21.
And a switch 25 provided on the upper side in the casing 21 and having two substantially parallel leaf spring-shaped contact pieces.

FIG. 10 is a top view of the vibration detection switch 20 with the lid 22 removed. When the outer tub 2 is stationary, as shown in FIG. 10A, the steel ball 24 is at the lowest position in the casing 21 by gravity, and the switch 25 is open. When vibration is generated mainly in the horizontal direction in the outer tub 2 as described later, a force due to acceleration also acts on the steel ball 24 in the horizontal direction.
4 rises on the inclined surface 21a. When the acceleration is large, FIG.
As shown in (b), the steel ball 24 rising on the inclined surface 21a pushes one contact piece of the switch 25, and both contact pieces come into contact. As a result, the switch 25 is closed, and it is detected that the acceleration due to the vibration is equal to or higher than a certain fixed value.

In order to detect that the steel ball 24 has risen on the inclined surface 21a, various methods can be adopted other than utilizing the mechanical contact of the leaf spring-like contact piece. For example,
An optical sensor or the like may be used to detect that the steel ball 24 has risen to a predetermined position.

Next, the electrical configuration of the main part of the drum type washing machine will be described with reference to FIG. The control unit 30 is a CPU,
It is mainly configured by a microcomputer including a ROM, a RAM, and the like, and functionally includes a central control unit 31, a PWM control unit 32, an eccentric load detection unit 33, and the like. The central control unit 31 includes a ROM in which an operation program for advancing the dehydration process is stored in advance, and in the course of executing the operation program, a target rotation speed of the motor 12 corresponding to a desired drum rotation speed is determined by the PWM control unit 32. To instruct.

The motor drive unit 40 includes a DC voltage supply unit 41,
It is configured to include an inverter control circuit 42 and functions as a drive control unit of the motor 12 together with the PWM control unit 32. The motor 12 is provided with a rotation speed detector 43, and a detection signal corresponding to the actual rotation speed of the motor 12 is output from the control unit 3.
It is fed back to 0. Specifically, the rotation number detector 43 is a pulse encoder, and is configured to generate one pulse signal every time the motor 12 rotates by a predetermined angle. A pulse signal (this pulse signal is hereinafter referred to as a “rotational speed pulse signal”) is output. FIG. 4 is a waveform diagram showing an example of the rotation speed pulse signal. When the rotation speed of the motor 12, that is, the drum 5, is high, the rising interval P of the rotation number pulse signal is narrow, and conversely, when the rotation speed of the drum 5 is low, the interval P is wide. As described above, the interval (hereinafter, referred to as “rotation speed pulse width”) P corresponds to the rotation speed of the motor 12 and the drum 5.

The PWM control unit 32 outputs a PWM control signal, which is a pulse signal having a predetermined cycle, to the inverter control circuit 4.
2 to perform PWM control by changing the "H" level time within one cycle period according to the difference between the target rotation speed and the actual rotation speed. That is, when the actual rotation speed is lower than the target rotation speed and the rotation speed needs to be increased, the "H" level time is extended, and conversely, the actual rotation speed is higher than the target rotation speed and the rotation speed is decreased. If it is necessary to shorten the time, the "H" level time is shortened. PWM
The control unit 32 calculates the actual rotation speed every time a rotation speed pulse signal is obtained from the rotation speed detector 43, and calculates P
Correct the "H" level time width of the WM control signal. By such control, a square wave voltage is applied to each winding of the motor 12.

The eccentric load detector 33 detects an eccentric load as follows. If the drum 5 is rotated at a rotation speed higher than the rotation speed at which the centrifugal force and the gravity acting on the laundry stored in the drum 5 are balanced (hereinafter referred to as “balanced rotation speed”), The object is pressed against the inner peripheral wall of the drum 5 and rotates as the drum 5 rotates. Now, in the case where the laundry is unevenly distributed and an eccentric load is generated, when the eccentric load is going to be lifted upward through the drum 5 minimum position as shown in a position A in FIG.
Gravity acting on the eccentric load is opposite to the direction of rotation. Therefore, the gravity acts to decelerate the drum 5. On the other hand, when the eccentric load is conveyed downward after passing through the highest position of the drum 5 as shown in a position B in FIG. 5, the gravity acting on the eccentric load becomes the same direction as the rotation direction. Thus, the gravity acts to accelerate the drum 5.

When a constant target rotation speed is instructed so that the rotation speed of the drum 5 is kept constant, the PWM control unit 32 outputs the "H" level time width of the PWM control signal (that is, P
(WM duty ratio) is changed so that the rotation speed of the motor 12 is maintained constant. On the other hand, when the PWM control unit 32 maintains the PWM duty ratio constant without performing the PWM control, the voltage applied to the motor 12 also becomes constant, and the rotational speed of the drum 5 fluctuates under the influence of the eccentric load as described above. . Actually, there is also the influence of the frictional force between the main shaft 8 and the bearing 10. When the eccentric load reaches a position near the highest position of the drum 5, the rotation speed becomes the lowest, and the eccentric load decreases at the lowest position of the drum 5. It becomes the highest when it reaches near. When the rotation speed pulse width P is plotted with time on the vertical axis, the relationship shown in FIG. 6 is shown. FIG.
Here, the plotted points of the black circles are data of the rotation speed pulse width P actually obtained, and M is a rotation marker obtained by the rotation sensor 19 and corresponding to a specific position on the inner circumference of the drum 5. .

As shown in FIG. 6, the rotation speed pulse width P fluctuates in synchronization with the rotation of the drum 5. Here, the difference α between the maximum rotation number pulse width Pmax and the minimum rotation number pulse width Pmin within one rotation period of the drum 5 reflects the amount of eccentricity.
Alternatively, the same applies to the ratio between Pmax and Pmin instead of taking the difference. Therefore, a number of experiments are performed in advance to determine the eccentricity and the difference α.
The correspondence between the eccentric load detection unit 33 and the table is created and stored in the ROM in the eccentric load detection unit 33. Eccentric load detection unit 33 during eccentric load detection processing
Is the rotation speed pulse width P given by the rotation speed detector 43.
Are sequentially stored in the RAM, and the maximum rotation speed pulse width Pmax and the minimum rotation speed pulse width Pmin are found at least when the data during the period during which the drum 5 makes one rotation is collected. Then, the difference α is calculated, and the eccentric amount is acquired with reference to the table.

Next, the characteristic control operation of the drum-type washing machine of the present embodiment during the spin-drying process will be described with reference to FIGS. FIG. 7 is a flowchart showing this control operation, and FIG. 8 is a graph showing an example of a change in the rotation speed of the drum 5 during the spin-drying process. In the following description, numerical values when the diameter of the drum 5 is 460 mm are taken as an example. However, when the drum diameter is different, it is possible to cope by appropriately changing the numerical values such as the rotation speeds. That is clear.

Immediately before the start of the spin-drying operation, all the laundry is in a state of sufficiently containing water, and is entangled with the bottom of the drum 5 and stacked. First, the PWM control unit 32 controls the PWM duty ratio by setting the target rotation speed of the drum 5 to 130 rpm (step S1). When the rotation speed of the drum 5 reaches around 130 rpm, the PWM duty ratio is fixed so that the rotation speed is maintained at about 130 rpm, and the eccentricity is determined by the rotation speed pulse signal obtained from the rotation speed detector 43 at that time. The load detector 33 detects the amount of eccentricity as described above (Step S2). And
The central control unit 31 determines whether the amount of eccentricity is equal to or less than a predetermined allowable value (Step S3).

If the amount of eccentricity exceeds the allowable value,
If the rotation speed of the drum 5 is increased as it is, there is a high possibility that abnormal vibration will occur. Therefore, the rotation of the drum 5 is temporarily stopped, a loosening operation is performed (step S4), and then the process returns to step S1 to rotate the drum 5 Increase speed again. In the loosening operation, for example, the drum 5 is rotated at a rotation speed (for example, 45 to 55 rpm) at which washing and rinsing are performed, and the laundry is agitated so that each laundry is easily peeled off.

If it is determined in step S3 that the amount of eccentricity is equal to or less than the allowable value, the PWM control unit 32 sets the target rotation speed to 500 rpm and rapidly increases the rotation speed of the drum 5 (step S5). . The resonance frequency at which the vibration of the drum 5 becomes extremely large depends on the weight of the drum 5 and the like, but is usually around 200 rpm. Therefore, as shown in FIG. 8, the eccentric amount quickly passes the rotational speed near the resonance point with a small amount of eccentricity, so that large vibration does not occur.

The central control unit 31 determines that the rotation speed is 500 rpm
m, the timer starts counting, and after waiting for one minute to elapse (“Y” in step S6),
It is determined whether or not the vibration detection switch 20 has been turned on (step S7). When the drum 5 is rotated at 500 rpm, dehydration from the laundry proceeds gradually. Therefore, 50
When the drum 5 is rotated at 0 rpm for one minute, a part of the water contained in the laundry is drained. At this time, dehydration proceeds in clothing made of fibers that are relatively easy to drain, such as chemical fibers, and the rate of weight loss is large, whereas dehydration is performed mostly in clothing made of fibers that are relatively hard to drain, such as cotton. The rate of weight loss is small. Therefore, even if the amount of eccentricity is small earlier in the determination in step S3, the amount of eccentricity increases due to the progress of dehydration, and the eccentricity causes the drum 5 to oscillate and the outer tub 2 to shake greatly. Sometimes. When the acceleration of the swing increases by a certain degree or more, the vibration detection switch 20 is turned on as described above.
I do. Therefore, in the above step S7, the vibration detection switch 2
When 0 is ON, it is determined that the eccentric load has increased in the process of steps S5 and S6, and that there is a high possibility that abnormal vibration will occur if the rotation speed is further increased.
Therefore, in this case, the maximum spinning speed is set to 500 rpm.
m (step S8).

In step S7, the vibration detection switch 20
Is not ON, it can be determined that there is no increase in the eccentric load at least at that time, or that it is not so large, if any. Thus, the PWM control unit 32 performs control to gradually increase the rotation speed from 500 rpm (Step S9). Then, each time the rotation speed slightly increases, it is determined whether or not the vibration detection switch 20 has been turned on (step S10).

If the vibration detection switch 20 is not ON, it is determined whether or not the rotation speed at that time has reached 700 rpm (step S12).
If it is less than 0 rpm, the process returns to step S9. Therefore,
If the vibration detection switch 20 is not turned on until the rotation speed reaches 700 rpm, steps S9 → S10 → S1
After repeating 2 → S9 →..., The process proceeds to step S13, and the maximum spin-drying rotation speed is set to 1000 rpm.

If the vibration detection switch 20 is turned on before the rotation speed reaches 700 rpm, the process proceeds from step S10 to S11, and the maximum dehydration rotation speed is set to 70.
Set to 0 rpm. Steps S8, S11, S1
When the maximum spinning speed is set in any one of Steps 3, the spinning is performed for a predetermined time at the spinning speed (Step S1).
4). This predetermined time can be changed according to the maximum spinning speed for dehydration or according to another parameter such as a load.

L1, L2, and L3 shown in FIG. 8 are lines indicating the rotation speed during the dehydration operation when the maximum dehydration rotation speed is set in steps S8, S11, and S13, respectively.
The higher the rotation speed, the higher the dewatering efficiency. Therefore, when the maximum dewatering rotation speed is suppressed to 500 rpm or 700 rpm, the dewatering efficiency is inferior to the case where the rotation speed is increased to 1000 rpm. However, even at such a rotational speed, sufficient dehydration is possible by continuing the dehydration operation for an appropriate time.

As described above, in the drum type washing machine of the present embodiment, whether the vibration detection switch 20 is turned on while the drum 5 is rotating at a rotation speed at which dehydration can be actually performed is determined by whether or not the outer tub 2 is turned on. When the vibration state is grasped and abnormal vibration is highly likely to occur, excessive vibration can be avoided beforehand by completing the dehydration at a relatively low rotation speed.

The above embodiment is merely an example, and it is apparent that changes and modifications can be made within the spirit of the present invention. For example, the above embodiment is an example in which the present invention is applied to a drum type washing machine, but it is obvious that the same technique can be applied to a spiral type washing machine. In the case of a spiral washing machine, the outer tub having a bottomed cylindrical shape is arranged with the opening end face upward, so that the vibration detection switch may be installed on the bottom wall or the side wall of the outer tub.

[Brief description of the drawings]

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

FIG. 2 is a sectional view taken along the line a-a 'in FIG.

FIG. 3 is an electric configuration diagram of a main part of the drum type washing machine of the present embodiment.

FIG. 4 is a waveform chart showing an example of a rotation speed pulse signal obtained from a rotation speed detector.

FIG. 5 is a schematic diagram showing a relationship between forces acting on an eccentric load in the drum.

FIG. 6 is a graph showing a change in a rotation speed pulse width when an eccentric load exists.

FIG. 7 is a flowchart at the time of a dehydration process in the drum type washing machine of the present embodiment.

FIG. 8 is a graph showing an example of a change in the rotation speed of the drum during the spin-drying process in the drum type washing machine of the embodiment.

FIG. 9 is a longitudinal sectional view showing the structure of a vibration detection switch.

FIG. 10 is a top view of the vibration detection switch with a lid removed.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Machine frame 2 ... Outer tank 3 ... Spring 4 ... Damper 5 ... Drum 12 ... Motor 19 ... Rotation sensor 20 ... Vibration detection switch 21 ... Casing 21a ... Inclined surface 22 ... Lid 23 ... Screw 24 ... Steel ball 25 ... Switch 30 ... Control unit 31 ... Central control unit 32 ... PWM control unit 33 ... Eccentric load detection unit 40 ... Motor drive unit 41 ... DC voltage supply unit 42 ... Inverter control circuit 43 ... Rotation speed detector

Claims (5)

[Claims] 1. A washing and dewatering tub is rotatably provided inside an outer tub that is swingably disposed inside a machine frame, and is accommodated in the washing and dewatering tub by rotating the washing and dehydrating tub at high speed. A) a washing machine that performs centrifugal dehydration of the laundry, a) vibration detection means for detecting that the vibration of the outer tub is equal to or more than a predetermined value, and b) speed detection means for detecting a rotation speed of the laundry dehydration tub. C) increasing the rotation speed of the washing and dewatering tub to a rotation speed at which laundry can be dehydrated, and using the vibration detection means and the speed detection means, at a point in time when vibration equal to or greater than a predetermined value is detected. An operation control means for determining a maximum spinning rotation speed according to the rotation speed. 2. The washing machine according to claim 1, wherein the operation control means includes: c1) when the washing dewatering tub is rotating at a predetermined rotational speed, vibrations equal to or greater than a predetermined value are detected by the vibration detecting means. C2) when the first determining means determines that a vibration equal to or more than a predetermined value is not detected, the rotation speed is gradually increased from the predetermined rotation speed. In the process, a second determining means for examining the rotation speed at the time when the vibration detecting means detects a vibration equal to or more than a predetermined value, and c3) a result obtained by the first determining means and a result obtained by the second determining means. A speed determining means for determining a maximum spin-drying rotation speed according to the set rotation speed. 3. The washing machine according to claim 1, wherein the vibration detecting means is disposed so as to roll up and down on a surface inclined up and down in the direction of rolling of the outer tub. A washing machine, comprising: a spherical body formed as described above; and position detecting means for detecting that the spherical body has reached a predetermined position by rising on an inclined surface. 4. The washing machine according to claim 1, wherein the washing and dewatering tub is a drum that is rotated about a substantially horizontal axis, and the vibration detecting unit includes the drum. A washing machine, which is installed on an upper part of an outer tub. 5. A washing and dewatering tub is rotatably provided inside an outer tub which is swingably disposed inside the machine frame, and is accommodated in the washing and dewatering tub by rotating the washing and dehydrating tub at a high speed. In a washing machine for performing centrifugal dehydration of laundry, a vibration detecting device installed in the outer tub to detect vibration of the outer tub, wherein: A) a spherical body arranged to roll on the inclined surface; and c) position detecting means for detecting that the spherical body has reached a predetermined position by ascending the inclined surface. A vibration detecting device for a washing machine, comprising: