JPH02249595A - Drum type washing machine - Google Patents

Abstract

PURPOSE:To accurately decide a negative load and to control a water quantity and a power amount to a proper value by a method wherein closed loop phase control is made on an induction motor to rotate a drum, a phase angle is calculated by means of an output from a rotation sensor and an output from a speed set circuit, and from a relation between 8 phase angle and a load amount, a load amount is computed. CONSTITUTION:When laundry 11 is charged in a drum 1 and a start switch is turned ON, a given amount of water lower than a rated feed water amount is fed. After completion of the feed of water, a speed setting circuit 8 sets the speed of a motor 2 to a value at which the drum 1 is rotated at the number of revolutions 1/5-1/10 the rated number of revolutions to output it to a comparing computing circuit 6. The comparing computing circuit 6 compares a speed signal 100 from a number of revolutions sensor 5 with an output from a speed setting circuit 8, and closed loop phase control is effected on the motor 2 so that a speed is adjusted to a value set by the speed setting circuit 8. In this case, the comparing computing circuit 6 reads a phase angle, provided due to a fluctuation in a load during seconds, to average the phase angles, and based on the averaged phase angle, a load amount is computed. This constitution enables to control using water quantity and a power amount to a proper value.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a drum-type washing machine that rotates a drum for storing laundry, and particularly to determining the load amount of laundry stored in the drum.

[Conventional technology]

Drum-type washing machines supply laundry and a predetermined amount of water to a freely rotatable drum, and the rotation of the drum is controlled by a motor to perform washing.In order to control the appropriate amount of water and power, the inside of the drum must be There is a need to accurately determine the amount of load.

Conventionally, a drum-type washing machine that determines the load amount of laundry stored in the drum is described in Japanese Utility Model Publication No. 61-42535. An electromechanical transducer is provided, and the electromechanical transducer detects the weight of the drum or a change thereof to determine the amount of laundry to be loaded into the drum.

[Problem to be solved by the invention] Conventional drum-type washing machines had the above-mentioned configuration, so it was necessary to install electromechanical converters in all parts of the drum that received the heavy base, which led to increased costs. There is a problem in that the device becomes more complicated as the method increases.

This invention was made to solve the above problem, and it is possible to accurately determine the load amount and appropriately control the water amount and 7U power without the need to newly install an electromechanical converter such as a strain gauge. The object of the present invention is to obtain a drum-type washing machine with high performance.

[Means for Solving the Problems] The drum-type washing machine according to the present invention has an AC power supply that supplies an AC current, and an induction drive that drives a rotatable drum that stores laundry by the AC power supplied from the AC power supply. It is equipped with an electric motor, a co-rotating sensor that detects the rotation speed of the induction motor, a speed setting circuit that sets the rotation speed of the induction motor, and a comparison calculation circuit that inputs the output of the speed setting circuit and the output of the rotation sensor. be.

[Function] Based on the above configuration, the drum into which laundry is loaded and a predetermined amount of water supplied smaller than the rated water supply amount is rotated from 115 to 1/2 of the rated rotation speed by an induction motor whose phase is controlled in a closed loop by a comparison calculation circuit. It rotates at a rotation speed of 10. Then, a comparison calculation circuit that inputs the output of the rotation sensor that detects the rotation of the induction motor and the output of the speed setting circuit calculates the phase angle, and calculates the load amount from the relationship between the phase angle and the load amount. do.

[Examples] Examples of the present invention will be described below with reference to the drawings.

As shown in Figures 1 and 2, a drum-type washing machine has an induction motor (hereinafter referred to as F1 motor) (2) for rotating a drum (1) that stores laundry (11). The motor (2) is supplied with AC power from an AC power source (3). The AC power supplied from the AC power source (3) is controlled by a triac (4).

The motor (2) also has a rotation sensor (
5) is provided, and the rotation sensor (5) is connected to a comparison calculation circuit (6).

Furthermore, the comparison calculation circuit (6) includes a zero volt sensor (7) for detecting zero volt of the AC power supply, and a zero volt sensor (7) for detecting zero volt of the AC power supply, and a
A speed setting circuit (8) for setting the rotation speed of the triac and a trigger circuit (9) for generating an ignition pulse are connected, and the trigger circuit (9) is connected to the triac (4). Note that L indicated by (10) in the figure is a phase advance capacitor.

Next, the operation of this embodiment will be explained.

When the laundry (11) is loaded into the drum (1) and a start switch (not shown) is turned on, a predetermined amount of water smaller than the rated water supply is supplied. After the water supply is completed, the speed setting circuit (8) sets the speed of the motor (2) to a speed that rotates the drum (1) at a rotation speed of 1/10 from 115 of the rated rotation speed, and the comparison calculation circuit ( 6).

Then, the comparison calculation circuit (6) compares the speed signal (100) from the rotation sensor (5) with the output of the speed setting circuit (8), and the speed becomes the speed set by the speed setting circuit (8). The motor (2) is controlled in a closed-loop phase as shown in FIG.

At this time, it has been found through experiments that the phase angle varies depending on the amount of laundry (11) loaded into the drum (1), that is, the load amount (see Figures 2 (a) to (d)). ).

Furthermore, if the load m is W and the phase angle is t, W-a-bt
It can be expressed as (see Figure 3). That is, when the load a cwt is a person, the phase angle (tl) becomes small and the load Q (W
2) is small, the phase angle (t2) becomes large (Fig. 3?
(see). Note that a and b are constants.

Then, the comparison calculation circuit (6) reads and averages the phase angles for several seconds, and calculates the load amount by substituting the averaged phase angle into the phase angle-load amount relational expression (W-a-bt). .

Then, the comparison calculation circuit (6) performs the washing operation by appropriately supplying water based on the load amount determined by the calculation, and further determining the washing time, the number of rinses, the spin-drying time, etc.

This makes it possible to optimize the amount of water and electricity used.

Further, based on the load amount, the comparison calculation circuit (6) can display the washing end time on a display section (not shown) in advance.

[Effects of the Invention] As explained above, the present invention performs closed-loop phase control on an induction motor to rotate a drum loaded with laundry, calculates a phase angle based on the output of a rotation sensor and the output of a speed setting circuit, Since the load amount is calculated from the relationship between the angle of the mouth and the load amount, the load amount can be determined without the need for a new electromechanical converter.

[Brief explanation of drawings]

Fig. 1 is a phase control circuit diagram of an induction motor according to the present invention, Fig. 2 (a), (b), (c), and (d) are diagrams showing liquefaction of the phase angle due to negative Cf■, Fig. 3 is a diagram showing the relationship between phase angle and load amount. In the figure, (1) is a drum, (2) is an induction motor, (
3) is an AC power supply, (5) is a rotation sensor, (6) is a comparison calculation circuit, and (8) is a speed setting circuit. In addition, in the figures, the same reference numerals indicate the same or equivalent parts. (b) Changes in A due to negative f1 and l2 Figure 2 Load amount A and IJ I Wholesale each mouth 1 Figure 2 47-7 3. . 5 mouths! Yunchi Nsa diagram

Claims (1)

[Claims] an AC power source that supplies an alternating current; an induction motor that uses the alternating current supplied from the AC power source to drive a rotatable drum that stores laundry; a rotation sensor that detects the number of rotations of the induction motor; It includes a speed setting circuit that sets the rotational speed of the motor, and a comparison calculation circuit that inputs the output of the speed setting circuit and the output of the rotation sensor, and the comparison calculation circuit performs closed-loop phase control of the induction motor and Calculate the phase angle from the output and the output of the speed setting circuit,
A drum-type washing machine characterized in that a load amount is calculated from the relationship between the phase angle and the load amount.