JPH0788291A - Clothes drying machine - Google Patents

Abstract

PURPOSE:To make smooth drum rotation by sensing that a drum has stopped upon a certain inertial rotation and has made a swing-back motion during the power-off period for a motor, when the drum is to be switched from the regular to reverse rotating or vice versa, and then changing over the rotation of the motor. CONSTITUTION:A drum is rotated in the regular and reverse directions to dry clothes with stirring, wherein the power to a motor 14 is shut off after regular direction drive for approx. 15sec, when pulse signals will decrease along with the power shutoff to the motor 14 gradually in compliance with the inertial rotation of the drum to nullify at last. A microcomputer 32 judges whether pulse signals from a revolving speed sensing means 39 nullify or not after the power to the motor 14 is shut off, and when the complete stop of the drum is judged, the motor 14 is rotated in reverse direction. In case pulse signals do not nullify after the power to the motor is shut off, the motor 14 is rotated reversely during the inertial run of the drum with sensed pulses increasing.

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 while agitating them by driving a drum to rotate normally and reversely.

[0002]

2. Description of the Related Art In a conventional clothes dryer, the contact area between the clothes and the dry air is repeated by introducing the dry air into the drum containing the wet clothes and repeating the forward rotation and the reverse rotation with respect to the drum at predetermined intervals. There is a structure in which the size is increased and clothes are quickly dried. Here, the clothes dryer having such a structure is, like the one disclosed in Japanese Patent Laid-Open No. 4-319394, when the start key is pressed after the power is turned on, the drying is started at the same time as the driving motor. Electricity is applied to rotate the drum forward, and 15 seconds after starting the normal rotation of the drum, the drive motor is stopped from being energized for 1 second. After the stop for 1 second, the drive motor is reversely rotated for 15 seconds. After that, the drum rotates forward in the same cycle,
It is configured to repeatedly perform reverse rotation.

[0003]

Generally, in such a conventional clothes dryer, when the drum is switched from forward rotation to reverse rotation and vice versa, even if the drive motor is de-energized. At the same time, the drum does not stop completely, but the inertia rotation causes the drum to continue the rotational movement due to inertia. The time of this inertia rotation changes depending on the weight of the clothes stored in the drum. For example, if the weight of clothes stored in the drum is relatively heavy, such as when the amount of clothes is large, or when the clothes have not dried yet immediately after the start of drying, The inertial rotation time is shortened because the stored clothes act as an eccentric load to stop the rotation of the drum. On the contrary, when the amount of clothes is small, or when the clothes in the drum are relatively light, such as when the clothes are almost dry, the effect of keeping the drum stationary becomes small and the inertia rotation time becomes long. As described above, the inertial rotation time of the drum greatly varies depending on the amount of clothes and the degree of drying.

However, if the stopping time of the motor for driving the drum is set to a constant value as in the conventional clothes dryer, it is very difficult to cope with the change in the inertial rotation time due to the amount of clothes and the dryness. Becomes If the inertial rotation time of the drum is longer than the set stop time, the motor will rotate in reverse before the drum stops completely,
Since the reverse rotation impact load is applied to the drive unit of the drum, not only the reverse rotation operation of the drum becomes rough, but also the drive unit may be unnecessarily burdened.

Further, when the inertial rotation time of the drum is shorter than the set motor stop time, the drum completely stops unnecessarily, and the balun of the clothes is broken, resulting in a long drying time. It had the drawback that

The present invention has been made to solve such a problem, and its purpose is to prevent the inertial rotation of the drum when switching from the normal rotation to the reverse rotation and from the reverse rotation to the normal rotation. By changing the timing of switching the motor from normal rotation to reverse rotation or from reverse rotation to normal rotation, the drum rotation can be performed smoothly and the drying time can be shortened. It is to provide a clothes dryer.

[0007]

[Means for Solving the Problems] A clothes dryer main body, a drum horizontally supported in the main body to stir clothes by forward and reverse rotations, a heating device, and a drying air heated by the heating device. An air blower introduced into the drum, a motor for rotationally driving the drum, the motor, the heating device,
The load driving means for controlling the load of the blower means, the rotation speed detecting means for detecting the rotation speed of the motor, and the rotation speed detecting means for the drum after the forward rotation (reverse rotation) of the motor is stopped. Control to detect the presence or absence of rotation due to swing-back after inertial rotation and instruct the load drive circuit to drive the motor from forward rotation (reverse rotation) to reverse rotation (forward rotation) by the detection signal that detects swing-back rotation Equipped with means.

[0008]

According to the present invention, the drum is inertially rotated and stopped during the energization OFF period of the motor when the drum is switched from the normal rotation to the reverse rotation or from the reverse rotation to the normal rotation, and further, the swing-back operation is performed in the opposite direction. The control means detects that the motor rotation speed is detected by a signal from the motor rotation speed detection means, and instructs the load drive circuit to switch the motor to reverse rotation or forward rotation, thereby smooth drum rotation. It becomes possible to obtain.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A coin type clothes dryer as an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of the clothes dryer of the present invention, and FIG. 2 is a rear view of the same. Figure 1
1, 1 is a clothes dryer main body divided into upper and lower stages, 2 and 3 are respectively provided in upper and lower stages, and a drying chamber including a horizontal shaft type drum for storing clothes and an outer tank 4, 5 are filters for catching lint such as lint generated in the drying chambers 2, 3. 6 is the drying chamber 2,
3 is a control unit which is disposed between 3 and is also used for the drying chambers 2 and 3, and has a display unit 7, a start switch 8 and a coin slot for displaying the remaining time and the coin insertion amount on the front surface. 9 are arranged. Clothing inlets to the drums are formed on the front surfaces of the drying chambers 2 and 3, respectively, and are opened and closed by doors 10 and 11.

Next, in FIG. 2, 12 and 13 are large pulleys mounted on the rear shaft of the drum, 14 and 15 are drive motors, and 16 and 17 are mounted on the drive motors 14 and 15 and are attached to the drum. A small pulley that is connected to the large pulleys 12 and 13 provided through belts 18 and 19, and the drum drives the driving force of drive motors 14 and 15 from the small pulleys 16 and 17 by the belts 18 and 19. It is rotationally driven by transmitting to the large pulleys 12 and 13,
The drum is configured to rotate normally and reversely when the drive motors 14 and 15 rotate normally and reversely. Two
Reference numerals 0 and 21 are gas burners which are heating devices, 22 and 23 are fan devices (not shown) and fan motors 24 and 25, and 26 and 27 are exhaust ports. The air heated by the gas burners 20 and 21 is supplied to the fan motor 2
The clothes are introduced into the drum by the fans driven by the fans 4, 25, and the clothes contained in the drum are dried, and at the same time, the steam generated from the clothes is discharged backward from the exhaust ports 26, 27. ing.

FIG. 3 is a front view of the drive motor 14. The drive motor 15 has the same configuration, and the description thereof is omitted here. In the figure, 28 is a disc fixed to an output shaft 29 of the drive motor 14, a disc provided on the opposite side of the small pulley 16, and 30 are magnets arranged on the disc 28 with the output shaft 29 as a center. , 31 are Hall elements provided to face the magnet 30 and provided on a fixed plate 32 fixed to the drive motor 14, and the magnet 30 and the Hall element 31 constitute a rotation speed detecting means 39. However, the rotation speed is detected by the pulse input when the magnet 30 crosses the Hall element 31.

FIG. 4 is a control block diagram of the clothes dryer according to the present invention. In FIG. 4, reference numeral 32 denotes a microcomputer which is the control means of the present invention. The microcomputer 32 receives the coin insertion information from the coin switch circuit 33, the door opening / closing information from the door switch 34 provided on the doors 10 and 11, the reset switch 35 from the dip switch 36, and the reset switch 35. Indicates the dip information, the temperature information from the thermistor 37 provided at the air inlet to the drum, and the temperature information from the thermistor 38 provided at the air outlet from the drum in accordance with the number of revolutions from the hall element 31 which is the revolution number detecting means 39. Each captures pulse information. Further, each information is taken in from the backup detection circuit 40, the power failure detection circuit 41, and the power supply circuit 43 connected to the commercial power supply 42, and the clock is taken in from the clock oscillation circuit 44.

Based on the information thus fetched, the microcomputer 32 issues a forward rotation and reverse rotation commands to the load drive circuit 45, and respective drive and stop commands to the fan motors 24 and 25, and the igniter 46. A command to the gas valve 47 and the safety valve 48 is output, and an amount display and a remaining time display are displayed on the display unit 7.

Next, the rotating operation of the drum of the clothes dryer of the present invention will be described with reference to the flowchart of FIG. Based on the signal from the clock oscillator circuit 44, the microcomputer 32 instructs the load drive circuit 45 to drive the motor 14 in the normal rotation for 15 seconds. The load drive circuit 45 rotates the drum in the forward direction (step 1), and after the motor 14 is driven in the forward direction for 15 seconds, stops energizing the motor 14 (step 2). Further, the microcomputer 32 detects the rotation speed of the motor based on the pulse input from the rotation speed detection means 39. The rotation speed detection means 39 detects the rotation of the magnet 30 provided in the motor 14 as the number of pulses output by the hall element 31, and the microcomputer 32 counts the pulse signal (detection signal) to determine the rotation speed of the motor. To do. The pulse signal of the rotation speed detection means 39 has a correlation with the rotation speed of the drum, and after the power supply to the motor 14 is stopped, the pulse signal similarly decreases as the rotation speed of the drum decreases.

Here, in step 2, the motor 14
The drum does not completely stop even when the power supply to is stopped, and inertial rotation is performed. The time and operation of this inertial rotation change depending on the weight of the clothes stored in the drum as described above, and when the amount of clothes is large or the dryness of the clothes is low, the drum energizes the motor 14. It stops almost immediately after stopping, and then swings back in the opposite direction.
At this time, the pulse signal from the rotation speed detection means associated with the rotation of the drum is as shown in FIG. 6a.

In FIGS. 6A and 6B, in a, the vertical axis represents the number of pulse signals, the horizontal axis represents time, in b, the vertical axis represents whether or not the motor is energized, and the horizontal axis represents time. In FIGS. 6a and 6b, when the motor is energized, the number of pulse signals increases as the rotation of the drum increases, and then the rotation of the drum becomes constant and the pulse signal also stabilizes at a constant value. The pulse signal sharply decreases in response to the inertial rotation of the drum when the motor is de-energized, and increases when the drum performs the swing-back operation in the opposite direction.

On the other hand, when the amount of clothes stored in the drum is small and the load is close to no load, the drum is completely stopped after inertial rotation for about 1 to 5 seconds after stopping the power supply to the motor. The pulse signal at this time is as shown in FIG. Figure 7a,
At point b, the pulse signal is gradually reduced at the same time when the power supply to the motor is stopped, and then the pulse signal becomes zero. The microcomputer 32 stops the energization of the motor in step 2, and then the rotation speed detecting means 39.
It is determined whether or not the pulse signal from is 0 (step 3). Here, when it is detected that the pulse signal has become 0, the microcomputer 32 determines that the drum is completely stopped, and the load driving means 15
The instruction for reverse rotation for 2 seconds is given, and the load driving means is the motor 14
Is reverse-driven for 15 seconds (steps 5 and 6).

On the other hand, when the pulse signal from the rotation speed detecting means 39 does not become 0 after the motor energization is stopped,
The microcomputer 32 determines whether or not the pulse signal increases (step 4), and when it is determined that the detection pulse increases, the drum performs the swing-back operation in the opposite direction after inertial rotation. It is determined that the motor 14 is reversely rotated for 15 seconds to the load driving means, and the motor 14 is reversely driven for 15 seconds (steps 4, 5,
6).

On the other hand, when the microcomputer 32 determines in step 4 that the pulse signal has not increased, it is determined that the drum is inertially rotating, and step 3
Return to. After performing reverse rotation of the drum for 15 seconds in steps 5, 6, and 7, the pulse signal from the rotation speed detecting means 39 is 0 by the microcomputer 32 as in steps 3 and 4, or increases if not 0. If it is determined whether or not to perform (steps 7, 8, and 9), and if it is determined that the drum is stopped or shaken back, the load drive means is instructed to drive the motor 14 in the normal rotation for 15 seconds (step 10). ). Then, it is judged whether or not the operation is completed (step 11), and if the operation is completed, the operation is completed (step 1).
2) If the operation is not completed, the process returns to step 1, and thereafter, the motor 14
The forward rotation and the reverse rotation of are repeatedly performed.

With the above configuration, the rotational speed detecting means detects the inertial rotation of the drive motor accompanying the inertial rotation of the drum during the motor energization stop period when the drum is switched from the normal rotation to the reverse rotation and from the reverse rotation to the normal rotation. Is detected as a pulse signal, and when the pulse signal is 0 or increased, the motor is rotated in the reverse direction (forward rotation), so that the optimum drum reverse rotation (forward rotation) timing according to the weight of the load in the drum is set. Will be able to.

[0021]

According to the present invention, it is possible to detect the presence or absence of rotation due to swinging back after inertial rotation of the drum when power supply to the motor is stopped when switching from normal rotation to reverse rotation of the drum and switching from reverse rotation to normal rotation. However, by configuring the motor to rotate in the reverse direction (forward rotation) when the swing-back is detected,
It is possible to prevent the drum from rotating in the opposite direction during inertial rotation, so that the load on the drum drive section is not burdened, and smooth drum rotation control is always possible according to fluctuations in the weight of the load inside the drum. Become. Further, by eliminating unnecessary motor stop time when switching the rotation of the drum, the overall drying efficiency can be improved and the drying time can be shortened.

[Brief description of drawings]

FIG. 1 is a front view of a clothes dryer according to an embodiment of the present invention.

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

FIG. 3 is an enlarged view of a main part showing a rotation speed detector.

FIG. 4 is a block diagram showing a control system of the clothes dryer of the present invention.

FIG. 5 is a flowchart showing drum reversal control in the clothes dryer of the present invention.

FIG. 6 is a diagram showing a change in inertial rotation when the load in the drum is heavy.

FIG. 7 is a diagram showing a change in inertial rotation when the load in the drum is light.

[Explanation of symbols]

 20, 21 Heating device 22, 23 Blower means 14, 15 Motor 39 Rotation speed detection means 32 Control means

Claims (1)

[Claims] 1. A clothes dryer main body, a drum horizontally supported in the main body to stir clothes by forward and reverse rotations, a heating device, and a drying air heated by the heating device introduced into the drum. A blower device, a motor for rotationally driving the drum, a load drive means for controlling loads of the motor, the heating device, the blower means, etc., and a rotation speed detection means for detecting a rotation speed of the motor, The rotation speed detection means detects the presence or absence of rotation due to swing back after inertial rotation of the drum after stopping the forward rotation (reverse rotation) of the motor, and rotates the motor forward (reverse rotation) by a detection signal that detects the swing back rotation. rotation)
The clothes dryer is provided with control means for instructing the load drive circuit to drive the load drive circuit in reverse rotation (forward rotation).