JPH04361791A - Washing machine - Google Patents

Abstract

PURPOSE:To provide a washing machine with the same specification usable in areas where different power frequencies are in use. CONSTITUTION:The rotating speed of a dehydrating tub 3 is detected by a rotating speed detecting means 19a, and the detected actual rotating speed and the upper limit set rotating speed are compared by the first comparing means 21a. When the actual rotating speed exceeds the upper limit set rotating speed, the excitation to a motor 4 is stopped by a motor stopping means 21b. The actual rotating speed of the dehydrating tub 3 and the lower limit set rotating speed are compared by the second comparing means 21c after the motor 4 is stopped, when the actual rotating speed becomes lower than the lower limit rotating speed, the excitation to the motor 4 is started by a motor starting means 21d.

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 more particularly to a washing machine having a spin-drying tub rotated by a motor.

0002

[Prior Art] Generally, in a washing machine, the rotation of the motor is transmitted to the dehydration tank by a belt transmission mechanism consisting of a driving pulley connected to the motor, a driven pulley connected to the dehydration tank, and a belt. . However, since the motor rotation speed is different in areas where the power frequency is 50Hz and 60Hz, washing machines with the same belt transmission mechanism (
When using washing machines with the same specifications (hereinafter referred to as "washing machines with the same specifications"), the rotation speed of the dehydration tank also differs depending on the power frequency. If a washing machine for 60 Hz is used in an area where the power supply frequency is 50 Hz, the number of revolutions of the dehydration tank will be lower than the number of revolutions that should normally be obtained. Therefore, the dehydration rate becomes worse. Also, if you use a 50Hz washing machine in an area where the power frequency is 60Hz,
The rotational speed of the dehydration tank is usually higher than the rotational speed that should be obtained. This has caused problems such as increased vibration and noise, which in turn shortens the life of the equipment.

[0003] Conventionally, in order to obtain the rotational speed of the dehydration tank that should normally be obtained for each power supply frequency, 2.
Drive pulleys with different diameters and belts with lengths determined by the diameters of the drive pulleys were prepared, and the belts were selected and incorporated into the product.

0004

[Problems to be Solved by the Invention] Conventionally, when manufacturing products to be used in regions with different power supply frequencies, it was necessary to select the drive pulley and belt during assembly. In addition, the label on the product and the labeling on the packaging materials differ depending on the power frequency, and there is also the hassle of having to sort the products by power frequency at the stage of distribution to the region.

[0005]

[Means for Solving the Problems] A washing machine based on the present invention is equipped with rotation speed detection means for detecting the rotation speed of a dehydration tub. The actual rotation speed detected by the rotation speed detection means and a preset upper limit rotation speed are compared by the first comparison means. Then, when the first comparing means determines that the rotational speed of the dehydration tank exceeds the upper limit set rotational speed, the motor stopping means stops energizing the motor.

After the power supply to the motor is stopped, the rotation speed detected by the rotation speed detection means is compared with a preset lower limit rotation speed by the second comparing means, and the rotation speed of the dehydration tank is determined as the lower limit. When it is determined that the rotation speed has become lower than the set rotation speed, the motor starting means starts energizing the motor.

[0007]

[Operation] When the rotation speed of the dehydration tank exceeds a preset upper limit rotation speed, the power supply to the motor is stopped, and the dehydration tank then rotates by inertia. Then, when the rotational speed of the dehydration tank, which is rotating due to inertia, falls below a preset lower limit rotational speed, the motor is energized again.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A washing machine according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a sectional view of a washing machine according to an embodiment of the present invention. A washing machine according to an embodiment of the present invention includes an outer box 1, a water receiving tank 2, a dehydration tank 3, and a drive unit 3.
It consists of 1.

[0010] The outer box 1 has a water receiving tank 2, a dehydration tank 3, and a driving section 31 inside thereof. The water receiving tank 2 has a dehydration tank 3 therein, and functions as a tank support for supporting the dehydration tank 3. The dehydration tank 3 has stirring blades 5 inside it,
It is connected to the dehydration shaft 9. The drive unit 31 is provided at the outer bottom of the water receiving tank 2.

The drive section 31 will be explained with reference to FIG. The drive unit 31 includes a motor 4 and a belt transmission mechanism 14.
and a clutch mechanism section 6.

The motor 4 is attached to the outer bottom of the water receiving tank 2 and has a motor rotation shaft 12. The belt transmission mechanism 14 includes a driving pulley 13, a V-belt 16, and a driven pulley 8. The driving pulley 13 is
It is composed of a pulley piece 13a, a cooling fan 13b, and a screw 13c, and is fixed to the motor rotating shaft 12. Therefore, the drive pulley 13 rotates together with the motor rotating shaft 12. The driven pulley 8 is connected to the driving pulley 13 via a V-belt 16, and has a magnet 20 on its lower surface. Further, the driven pulley 8 is fixed to the washing shaft 7 and the dewatering shaft 9, and rotates together with them.

[0013] Also, the reed switch 19 is connected to the magnet 2.
0 at a predetermined interval. Since the magnet 20 is attached to the lower surface of the driven pulley 8, it rotates together with the driven pulley 8, but the reed switch 19 is fixed at the above position.

The clutch mechanism 6 has a washing shaft 7 and a dewatering shaft 9.
, a spring clutch 10 , a solenoid 18 , and a clutch lever 17 .

The dewatering shaft 9 is provided on the outer peripheral surface of the washing shaft 7. The spring clutch 10 is provided on the outer peripheral surface of the dewatering shaft 9 and selectively transmits the rotation of the driven pulley 8 to the washing shaft 7 and the dewatering shaft 9. The solenoid 18 is attached to the outer bottom of the water tank 2, and is connected to the clutch lever 1.
It is connected to a spring clutch 10 via 7.

Note that this washing machine has a built-in microcomputer that plays a central role in its control, but it is not shown for convenience. Further, the driving pulley 13 and the V-belt 16 are compatible with a power supply frequency of 50 Hz.

Next, the operation of the washing machine having the above structure during dewatering operation will be explained. First, the clutch lever 17 is operated by the solenoid 18, and the spring clutch 10
is switched to transmit power to the dewatering shaft 9. By energizing the motor 4 in this state, the drive pulley 13 fixed to the motor rotating shaft 12 rotates. The rotation of the driving pulley 13 is transmitted to the driven pulley 8 via the V-belt 16. When the driven pulley 8 rotates, the dewatering shaft 9, which is fixed to the driven pulley 8 and rotates together with the driven pulley 8, rotates. As a result, the dehydration tank 3 rotates.

The control principle of the dewatering operation based on the present invention will be explained below with reference to FIG. FIG. 3 is a block diagram showing the control principle of dehydration operation based on the present invention.

First, when the motor 4 is energized, the dewatering tank 3 is rotated by the mechanism described above. Then, the rotation speed of the rotating dehydration tank 3 is detected by the reed switch 19 as the rotation speed detection means 19a. After that, the first comparison means 2
The microcomputer 21 as 1a compares the actual rotation speed of the dehydration tank 3 detected by the reed switch 19 with the upper limit rotation speed preset in the operating program. When the actual rotational speed of the dehydration tank 3 exceeds the upper limit rotational speed, the control section of the microcomputer 21 serving as the motor stopping means 21b stops energizing the motor 4.

After the power supply to the motor 4 is stopped, the dehydration tank 3 rotates due to inertia, so the number of rotations thereof gradually decreases. The rotation speed of the dehydration tank 3 is also detected by a reed switch 19 serving as rotation speed detection means 19a. The detected rotational speed is then compared with a lower limit rotational speed preset in the operating program by the microcomputer 21 as the second comparison means 21c. When the detected rotational speed becomes lower than a preset lower limit rotational speed, the control section of the microcomputer 21 as the motor starting means 21d starts energizing the motor 4.

Next, the microcomputer 21 which plays a central role in the control of the present invention will be explained with reference to the drawings.

As shown in FIG. 4, the microcomputer 21 has an operation switch 22 on the operation panel, a safety switch 23 linked to the opening and closing of the top cover, a pressure switch 24 as a water level detection means, an operation program, etc. set in the initial state. Information is input from a reset circuit 25 used as a timer, a clock circuit 26 used as a timer, and a reed switch 19 for detecting the number of revolutions. Various display circuits 28 display time, process, errors, etc. based on this information.
, a motor rotation drive circuit 29 that energizes the motor 4 and a capacitor (not shown), and a solenoid drive circuit 30 that operates a clutch and a drain valve.

Next, the dewatering operation of a washing machine according to an embodiment of the present invention will be explained with reference to the flowchart shown in FIG.

After the dewatering operation is started, in S1, the solenoid drive circuit 30 is energized to operate the drain valve and the clutch solenoid 18. Thereby, the dehydration tank 3 becomes rotatable by energizing the motor 4. After that, S2
When the pressure switch 24 detects that there is no more water in the dehydration tank 3, the process moves to S3. In S3, the motor 4 and the capacitor are energized through the motor rotation drive circuit 29. As a result, the dehydration tank 3 rotates.

[0025] Then, in S4, reed switch 1
9 detects the rotation speed of the dehydration tank 3, and the rotation speed is 85.
If the microcomputer 21 determines that the rotation speed is 0 rpm or more, the process moves to S5; otherwise, the process returns to S3 and energization of the motor 4 and the capacitor is continued. and,
In S5, power supply to the motor 4 and the capacitor through the motor rotation drive circuit 29 is stopped.

[0026] As a result, the dehydration tank 3 rotates due to inertia. Then, in S6, the number of rotations of the dehydration tank 3 which rotates due to inertia is detected by the reed switch 19, and the number of rotations is 7.
If the microcomputer 21 determines that the speed is 50 rpm or less, the process moves to S7; otherwise, the process returns to S5.
The dehydration tank 3 rotates by inertia until its rotational speed decreases to 750 rpm or less.

Then, in S7, the rotation speed of the dehydration tank 3 is increased by energizing the motor 4 through the motor rotation drive circuit 29. In this case, only the motor 4 is energized because the torque sufficient to increase the rotational speed of the dehydration tank 3, which is rotating due to inertia, can be obtained only by energizing the motor 4 without energizing the capacitor. Then, in S8, the rotation speed of the dehydration tank 3 is detected by the reed switch 19, and when the microcomputer 21 determines that the rotation speed is 850 rpm or more, the process moves to S9 and the power supply to the motor 4 is stopped.

Further, in S8, if the rotation speed of the dehydration tank 3 is less than 850 rpm, the process moves to S11. Then, in S11, the rotation speed of the dehydration tank 3 is set to 700 rpm.
If it is greater than or equal to m, the process moves to S7 and only the motor 4 is energized. However, the rotation speed of dehydration tank 3 is 700 rpm.
If the value is less than the current value, the capacitor is energized again in S12. This is a measure that assumes cases where the power supply voltage drops when used with equipment that requires a large amount of current, or cases that may occur depending on the condition and amount of clothing being dehydrated.

[0029] Then, in S13, if it is determined that the rotation speed of the dehydration tank 3 is 850 rpm or more, S13
14, the power supply to the motor 4 and the capacitor is stopped. After that, the process returns to S5 and the above-described control is repeated. Then, in S10, when the microcomputer 21 determines that the dehydration process time has elapsed, the process moves to the next process.

[0030] The washing machine having the structure and function as described above can control the number of revolutions of the dehydration tank 3 within a target range during dehydration operation. Therefore, with the washing machine based on the present invention, it is possible to keep the rotational speed of the dehydration tank 3 within a target range even if equipment with the same specifications is used in regions with different power supply frequencies.

[0031]

According to the present invention, it is possible to use washing machines with the same specifications even when the power supply frequency is different. This eliminates the need to select the drive pulley and V-belt for each power frequency during assembly. In addition, the nameplates and packaging materials displayed on products can be unified, eliminating the hassle of sorting products at the distribution stage.

[Brief explanation of drawings]

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

FIG. 2 is an enlarged view of the drive section in FIG. 1;

FIG. 3 is a block diagram showing the control principle of dehydration operation based on the present invention.

FIG. 4 is a block diagram showing a control section of a microcomputer built into a washing machine according to an embodiment of the present invention.

FIG. 5 is a flowchart showing a dehydration operation program for a washing machine according to an embodiment of the present invention.

[Explanation of symbols]

3 Dehydration tank 4 Motor 19 Reed switch 19a Rotation speed detection means 21 Microcomputer 21a First comparison means 21b Motor stop means 21c Second comparison means 21d Motor starting means

Claims (1)

[Claims] 1. A washing machine having a dehydration tank rotationally driven by a motor, comprising: a rotation speed detection means for detecting the rotation speed of the dehydration tank; and an actual rotation speed detected by the rotation speed detection means. A first comparison means for comparing the number of rotations with a preset upper limit rotation speed, and the first comparison means determine that the rotation speed of the dehydration tank exceeds the upper limit rotation speed. motor stopping means for stopping energization to the motor in accordance with the current state; and after stopping energization to the motor, the actual rotation speed detected by the rotation speed detection means and a preset lower limit rotation. In response to the second comparison means for comparing the number of rotations and the second comparison means determining that the rotation speed of the dehydration tank has become lower than the lower limit set rotation speed, A washing machine comprising: motor starting means for starting energization of the motor.