JPH05317588A - Clothes dryer - Google Patents

Abstract

PURPOSE:To perform drying appropriately by controlling the rotating speed of a drum and a fan without exchanging components corresponding to an AC power source frequency in a clothes dryer for household clothes. CONSTITUTION:A heat exchange fan which circulates warm air to the drum for drying clothes is provided, and a PTC heater 3 is provided at a blow route to the drum, and the drum and the heat exchange fan are driven rotatably by a motor 4. A rotation control means 5 which controls the rotating speed of the motor 4 controls the motor 4 so as to set the rotating speed at the preset rotating speed without depending on the AC power source frequency, thereby, stable rotating speed can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clothes dryer for drying clothes by circulating warm air in a drum for drying clothes.

[0002]

2. Description of the Related Art Conventionally, in this type of clothes dryer, the number of revolutions of a motor for driving a drum and a fan which is a blowing means depends on an AC power supply frequency. Therefore, the reduction ratio of the motor is 50 Hz or 60 Hz. By changing the number of rotations of the drum and the fan to the same, the influence of the frequency on the drying performance was eliminated.

[0003]

In such a conventional clothes dryer, it is necessary to replace the parts according to the frequency of the AC power source, and the products for 50 Hz and 60 Hz must be managed and sold separately. did not become. In addition, when the AC power supply frequency is used by mistake, there is a problem that the operation noise becomes loud, the operation is not finished yet, and the drying time becomes long.

The present invention solves the above-mentioned problems. It is not necessary to replace parts even if the AC power supply frequency is different, and the rotation speed of the drum and the fan is set to the set rotation speed regardless of the AC power supply frequency of 50 Hz and 60 Hz. The purpose is to control it so that it can be dried optimally even if the power supply frequency changes.

[0005]

In order to achieve the above object, the present invention has a drum for drying clothes, an air blowing means for circulating warm air into the drum, and a heating provided in an air blowing path to the drum. Means, a motor for rotationally driving the blower means or the drum, and a rotation control means for controlling a rotation speed of the motor, wherein the rotation control means sets the motor to a set rotation speed regardless of an AC power supply frequency. Controlling is the means for solving the problem.

[0006]

According to the present invention, the number of revolutions can be controlled to the set number of revolutions regardless of the AC power source frequency of 50 Hz or 60 Hz by the above-mentioned means for solving the problem, so that it is not necessary to replace the parts due to the difference of the AC power source frequency, and which frequency is used. It can be used even in the area of, and a stable rotation speed can be obtained because it is controlled to the set rotation speed every time the rotation speed is determined.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

As shown in the figure, the drum 1 accommodates a material to be dried, and a heat exchange fan (blower) 2 circulates warm air in the drum 1. The heat exchange fan 2 circulates warm air in the drum 1 and at the same time takes in air from the outside to cool the fan and dehumidify the circulating air in the drum 1. PTC
The heater (heating means) 3 is arranged in the air blowing path to the drum 1, that is, in the circulating air intake, and heats the circulating air. The motor 4 rotationally drives the drum 1 and the heat exchange fan 2 and controls the number of rotations of the motor 4 to control the number of rotations of the drum 1 and the heat exchange fan 2. The rotation sensor 50 for controlling rotation may be attached to the motor 4, but in the present embodiment, the rotation number of the drum 1 is detected, and the magnetic sensor 50a is fixed to the main body and the magnet 50b is attached to the drum. I am installing. 3 to 50 magnets 50b on the drum 1
The number of rotations can be detected and the set value can be controlled by attaching 6 pieces. By doing so, not only the stable rotation control of the motor 4 and the drum 1 can be performed, but also the failure of the belt, which is the rotation transmission means between the drum 1 and the motor 4, can be detected. When the drum 1 and the heat exchange fan 2 are driven by different motors, respectively, the drum 1 or the heat exchange fan 2
The rotation sensor 50 is attached to the drive motor.

The rotation control means 5 controls the rotation speed of the drum 1 to the set rotation speed of the rotation speed setting means 6, and the drum 1 detected by the rotation sensor 50 and the rotation speed detecting means 51.
The rotation speed of the motor 4 is controlled by comparing the difference in rotation speed between the rotation speed and the rotation speed of the rotation speed setting means 6 with the rotation speed comparing means 52 and controlling the power switching means 54 such as a bidirectional thyristor with the conduction time control means 53. Change the number. Phase control can be considered as the simplest conduction time control method. In the case of an inverter, not only the conduction time but also the frequency is controlled. The AC power supply 7 connects the PTC heaters 3a and 3b and the contacts 8a and 8b of the relay in series, respectively.

An outline of the operation of the above structure will be described with reference to FIGS. 3 and 4. FIG.
Is a current waveform at the time of full-wave energization, the rotation speed of the drum 1 is maximum at this time. In FIG. 3 (b), since the energization is performed only during the conduction time T, the rotation speed of the drum 1 can be changed according to the conduction time T. Magnetic sensor 50a of rotation sensor 50 and magnet 5
As shown in FIG. 4, when the four magnets 50b are attached to the drum 1, the on / off signal from 0b is 1 when the drum 1 is 0.
The magnetic sensor 50a is turned on four times while rotating. The rotation speed detecting means 51 uses the cycle Tx for each ON / OFF cycle (1/4 rotation of the drum) of the magnetic sensor 50a.
The number of rotations of is detected and judged. The rotation speed comparison means 52 compares the difference between the rotation speed of the drum 1 detected and determined by the rotation speed detection means 51 and the rotation speed of the rotation speed setting means 6, and the conduction time control means 53 controls the power switching means 54. , The drum 1 is controlled to the set rotation number every time the rotation number is determined. Therefore, the time required to reach the set rotation speed is short and a stable rotation speed can be obtained.

Next, the operation will be described in detail with reference to FIG. 5. First, at step 11, the rotation speed of the drum 1 is set. In step 12, the ON signal of the magnetic sensor 50a is detected, and every time the ON signal is detected, the rotation control subroutine of step 13 sets the set rotation speed Ns set by the rotation speed setting means 6 and the rotation speed detected by the rotation speed detection means 51. In comparison, the operation amount of the rotation speed control, that is, the conduction angle is controlled according to the error from the setting, and the rotation speed control is performed. When the drying is detected in step 15, the end of the drying operation is determined.

In this embodiment, the rotation sensor 50 is
Although it is attached to the drum 1, the same effect can be obtained by providing the heat exchange fan 2 or the motor 4. Further, the case where the number of rotations of the drum 1 and the heat exchange fan 2 is driven by one motor 4 is shown, but the effect is the same even when two motors are provided with respective motors. Further, although the magnetic sensor 50a and the magnet 50b are used as the rotation sensor 50, a reflection type or transmission type optical sensor may be used. In addition, the magnetic sensor 50a
Although the rotation speed is controlled for each ON signal of, the rotation speed may be controlled for every fixed time.

[0013]

As is apparent from the above embodiments, according to the present invention, a drum for drying clothes, a blowing means for circulating warm air in the drum, and a heating provided in a blowing path to the drum. Means, a motor for rotationally driving the blower means or the drum, and a rotation control means for controlling a rotation speed of the motor, wherein the rotation control means sets the motor to a set rotation speed regardless of an AC power supply frequency. Since it is controlled, a stable rotation speed of the drum or the blower can be obtained regardless of the AC power supply frequency.

Further, since the rotation control means detects the rotation speed of either the motor, the blowing means or the drum and controls the rotation speed to the set rotation speed every time the rotation speed is judged, the time to reach the set rotation speed is reached. A short and stable rotation speed can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram of a clothes dryer according to an embodiment of the present invention.

FIG. 2 is a sectional view of the clothes dryer.

[Fig. 3] (a), (b) Current waveform diagram of the motor of the clothes dryer

FIG. 4 is an ON / OFF signal waveform diagram of a rotation sensor of the clothes dryer.

FIG. 5 is an operation flowchart of main parts of the clothes dryer.

[Explanation of symbols]

 1 Drum 2 Heat Exchange Fan (Blower Means) 3 PTC Heater (Heating Means) 4 Motor 5 Rotation Control Means

Claims (2)

[Claims] 1. A drum for drying clothes, an air blowing unit for circulating warm air into the drum, a heating unit provided in an air blowing path to the drum, and a motor for rotationally driving the air blowing unit or the drum. And a rotation control means for controlling the rotation speed of the motor, wherein the rotation control means controls the motor to a set rotation speed regardless of an AC power supply frequency. 2. The clothes dryer according to claim 1, wherein the rotation control means detects the rotation speed of any one of the motor, the blowing means and the drum, and controls the rotation speed to a set rotation speed each time the rotation speed is determined. ..