JPS6088600A - Recirculation type clothing dryer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Industrial Application Field The present invention is directed to a circulating air path in which exhaust air from a drying chamber is cooled with a dehumidifier to remove water, then reheated with a heater and supplied to a drying unit. The present invention relates to a circulating clothes dryer having:

(b) Prior art In most conventional dryers, the operating time was determined by the user using a timer based on the type of clothing, moisture content, etc. There was a warning not to dry it for a long time or to dry it insufficiently.

Therefore, the exhaust temperature from the drying room or the degree of dryness is 80 [%]
Taking advantage of the fact that the temperature rises rapidly when the temperature reaches about Japanese Patent Application Laid-Open No. 19296/1983 proposes a method in which drying is terminated when the difference between the temperature and the exhaust temperature becomes larger than a predetermined constant value.

However, this device detects the outside air temperature as a temperature to compare with the exhaust temperature, and this outside air temperature becomes unstable when the dryer is used indoors (in this case, the outside air temperature becomes the indoor temperature). Also, if the air volume changes due to a clogged filter or the power supply voltage changes, the exhaust temperature changes and the outside temperature does not respond to these changes, making it difficult to control accurately at all times, resulting in dry air. There was a risk that the drying process would be completed without drying.

Furthermore, when applying icons, is it better to finish drying at a low drying rate?In this case, the drying rate will reach the same high drying rate as when not ironing, so it is impossible to immediately dry to the desired drying rate. There wasn't.

(c) Purpose of the Invention The purpose of the present invention is to provide a circulating clothes dryer that detects the degree of dryness desired by the user and finishes drying, without being influenced by external factors such as outside temperature. The goal is to get a dryer that can.

(D) Structure of the Invention The present invention provides that in a circulating clothes dryer, the temperature after passing through the dehumidifier in the circulation air path and the temperature after passing through the dehumidifier in the cooling air path show stable changes during drying. and a first heat-sensitive means for measuring the temperature of the air before passing through the dehumidifier in the circulation air path, that is, the temperature of the exhaust air from the drying room, taking into account that the temperature changes depending on the temperature of the exhaust air from the drying room. , a second heat-sensitive means for measuring the temperature of the air after passing through the dehumidifier in the circulating air path or the temperature of the air after passing through the dehumidifier in the cooling air path that cools the dehumidifier by applying outside air to the dehumidifier; storage means for storing the temperature difference as a reference value when the difference in temperature measured by both the heat-sensitive means reaches a substantially constant value after a predetermined time elapses; It has a control means for terminating the drying operation when the difference reaches a predetermined value or more or after a certain period of time has elapsed thereafter, and a changing means for changing the predetermined value to an arbitrary value. be.

(E) Embodiment An embodiment of the present invention will be explained based on the drawings. (1> is the outer box, the rear opening is closed by the back plate (2), and the front side is provided with a clothes slot (4) that is opened and closed by the door (3). The outer box (1) ) is made of synthetic resin, and a rib (90) or a protrusion is provided on the back surface for reinforcement.

(6) is a drum that serves as a drying chamber for storing clothes.A front plate (9) is fixed to the front end of the peripheral wall (7) of the drum, and the edge of this front plate (9) is fixed to the front of the outer box. drum support plate (
The outer periphery flange (12) of the lugs is fitted through a sliding member such as felt (13). A shaft (14) is protruded from the center of the rear wall (8) of the drum (6), and this shaft (14) extends from the cylinder (16) formed at the center of the support plate (15).
) through the metal (17), and the shaft (14)
A tapping screw (19) is also inserted into the tip of the shaft body (14) through a washer (18) to prevent the shaft body (14) from coming out from the tube (16). The support plate (15) is
) As shown in the figure, both ends are fixed to flanges (20) and (21) formed at the upper and lower rear ends of the outer box (1).

The rear wall (8) of the drum (6) has a plurality of air discharge holes (
22), and a rear duct (23) communicating with the inside of the drum (6) through this discharge hole (22) is fixed to the support plate (15). The discharge hole (22) has a removable filter cover (25) that covers the filter net (24).
) is covered. (26) is a sealing member that prevents air leakage between the rear tactile member (23) and the rear wall (8) of the drum (6).

The outlet (33) of the rear duct (23>) is connected to the suction duct (36) of the circulation fan casing (35) via the connecting vibe (34). 3) As shown in the figure, a circulation fan (37) consisting of a centrifugal fan is provided.
37) is a small pulley (39) fixed to its shaft (38).
) is connected to the shaft (42) of the motor (41) by the belt (40).
It is rotated by being connected to a dog pulley (43) fixed to. A small pulley (44) is also fixed to the shaft (42>) of the motor (41), and by winding a belt (45) between this small pulley (44) and the outer circumference of the drum (6), the Iζ ram (6) is also rotated at low speed. In Figure (2), (46) is an idler pulley that adjusts the tension of the heel (45).

The discharge duct (47) of the circulation fan casing (35) is communicated with one end side of a large number of pipes (49) of the dehumidifier (48). The dehumidifier (48) consists of these many pipes (49)
and a large number of cooling fins (50) perpendicular to this pipe. In Fig. (3), (51) is a cooling fan, which is installed inside a cooling fan casing (52), and a suction duct (53) of this casing (52) is connected to the outside air which opens on the top surface of the outer box (1). The cooling fan (51) is connected to the shaft (38) of the circulation fan (37), and the discharge duct (55) is connected to the upper end surface of the cooling fin (50). As the cooling fan (51) rotates, outside air is sucked through the outside air intake port (54) through the filter (61) as shown by the dotted line arrow in Figure (3), and the cooling fins (50) and send it to the pipe (
49) A cooling air path is formed by cooling the moist, warm air passing through the interior, condensing the moisture contained in it, and exiting it through the numerous exhaust holes (56) provided on the bottom of the outer box (1). do. The outer box (1) is attached to the other end of the large number of pipes (49).
One end of a front duct (57) formed in cooperation with the front side of the front duct (57) is connected to the
) is drained out of the machine from the drain hose (58) connected to the bottom surface of the drain hose (58).

The other end of the front duct (57) is connected to the drum support board (1), and the front duct (57) is connected to the drum support board (11).
7) A large number of air intake holes (5) communicating between the inside and the inside of the drum (6).
9) or is provided. A heater (60) is also installed inside the duct (57).

Then, when the heater (60) is energized and the motor (41) is rotated, the circulation fan (37), the cooling fan (51), and the drum (6) rotate.
4) Drum (6) from the intake hole (59) as shown by the solid arrow in the figure.
Air heated by a heater (60) is supplied into the drum to evaporate moisture from the clothes in the drum, and this hot and humid air flows through the filter cover (25) and the discharge hole (22) to the rear duct ( 23) and is discharged into the rear duct (2
3) through the connecting pipe (34) to a number of pipes (49) of the dehumidifier (48), where it is cooled as described above and the moisture contained therein is condensed, and then sent to the front duct (57). ) to the heater (60), where it is heated again, and then supplied to the drum (6) through the intake hole (59), repeating the cycle. Solid arrows represent circulation air paths.

In the discharge duct (47) of the circulation fan casing (35), there is a heat-sensitive element serving as a first heat-sensitive means for measuring the temperature of the air before passing through the dehumidifier in the circulation air path, that is, the drum outlet temperature. (61) is provided. Here, a thermistor is used as the thermal element (61). or,
Below the dehumidifier (48) in the cooling air path, there is a second heat-sensitive element (62) also made of a thermistor, which is a second heat-sensitive means for measuring the temperature of the air after passing through the dehumidifier, that is, the temperature at the outlet of the dehumidifier. It is provided.

Next, the control circuit will be explained based on Fig. (5). (63
) is the power on switch, (64) is the first door switch,
(41) is the motor, and (60) is the heater. (
Reference numeral 65) is a DC converting circuit, which converts the DC voltage rectified into rectangular wave pulses in a waveform shaping circuit (66), and applies the pulses to a microcomputer (67) for use in time counting. (68) A clock oscillation circuit generates pulses used to advance the program in the microcomputer (67). (69) is an initial set circuit, and when the power supply switch (63) is pressed, this initial reset circuit operates to set the program in the microcomputer (67) to its initial state. (61) is a thermistor as the first heat-sensitive element;
(62) is a thermistor as the second heat-sensitive element, each thermistor is connected in series with a resistor (70) and (71), respectively, and the respective divided voltage values are input to voltage comparators (72) and (73). . The other input terminal of each voltage comparator (72) (73) receives an output signal from a ladder circuit (74) that generates a staircase wave upon receiving the output from the microcomputer (67). This ladder circuit is connected to the output terminals (A), (B), ... (G) of the microcomputer (67), and as signals are sequentially output from each output terminal, the output voltage of the ladder circuit (74) increases. Changes in a step-like manner,
When the voltage comparators (72) and (73) become conductive and there is an input to the microcomputer (67), it means that the signal is output from any of the output terminals (A), (B), ... (G). The microcomputer itself determines whether the time is right.
The temperature at the drum outlet of the circulating air path and the dehumidifier outlet temperature of the cooling air path are known. (77) is the second door switch for determining whether or not the clothes loading door is closed; (78) is the 50/60Hz changeover switch; (75) (
91) (92) are start switches for starting the drying operation, and any switch (75) (91) (92)
) is pressed, drying operation will start according to the operation course corresponding to each switch. (79) is the first relay winding, and when any of the start switches (75), (91, and 92) is pressed, the output signal from the microcomputer (67) is used to send the first relay winding through the transistor. A current flows through the wire (79), closing the first relay contact (79') and energizing the motor (41). or(
80) is a second relay winding; (81) is a light emitting diode for drying operation display; when the drying process has progressed, the signal output from the microphone 7 computer (67) energizes the issuing diode (81) via a transistor. , lights up to indicate that the drying process is in progress, and also energizes the second relay winding (80) to close the second relay contact (80).
') is closed, and the heater (60) is energized through the first door switch (64) and the like. (84) is a light-emitting diode for a cold-air operation table for fishing during cold-air operation. (86) is a power source.

The operation of the above configuration will be explained below. When the power-on switch (63) is pressed, DC voltage is applied to the microcomputer (67) through the DC conversion circuit (65), and the initial clear circuit (69) is activated to set the program in the microcomputer to its initial state. The program is sequentially advanced by a signal from the clock oscillation circuit (68), or first the thermistor (61) as the first heat-sensitive element and the thermistor (62) as the second heat-sensitive element.
Then, the drum outlet temperature and dehumidifier outlet temperature are measured at 1 second intervals by the ladder circuit (74) voltage comparators (72) and (73), and the values are sent to the RA in the microcomputer (67).
Store in M (read memory). Press any of the start switches (75), (91), and (92), and if the clothes loading door (3) is closed, the first and second door switches (64, 77) are closed. The microcomputer (6) indicates that the second door switch (77) is closed.
7) detects and outputs an output current to the first relay winding (79), closes the first relay contact (79') and connects the motor (41).
energizes the drum (6) and both fans (37) (5).
1), an output current is also output to the second relay winding (80), the second relay contact (80') is closed, and the heater (60) is connected to start the drying operation. In addition, the macrocomputer (67) converts the power AC wave into a waveform shaping circuit (
66), the number of pulses converted into a rectangular wave is counted to count the operating time. This counting is performed by using a specific address in the RAM as a time counter, and the time counted and stored here is updated every minute.

By the way, the difference between the drum outlet temperature and the dehumidifier outlet temperature measured by the first and second heat-sensitive elements (61) and (62) changes approximately as shown in Fig. 6) during the drying operation.

That is, the difference between the two temperatures increases for a while after the start of the drying operation, but when a certain temperature difference (A) is reached, a steady state is reached and there is almost no change. After this steady state continues for a while, the difference between the two temperatures begins to increase again, but the drying rate at this time is approximately 80%. Therefore, in Figure (6), if the drying operation is stopped when the difference between the two temperatures reaches (A + B) degrees (where B is any predetermined positive number), the drying rate will be 80% or more, and the drying rate will be 80% or more. By changing the value of B, the drying rate can be adjusted between 80% and 100%.

Note that the time required for the difference between the two temperatures to become approximately constant (T
1) is determined by experimenting with various loads that may vary depending on the load amount and dehydration rate, and setting the longest time among them as the time (T1), and the difference between the two temperatures at that time as the temperature difference (A). do it. However, since the steady state is quite long, the time (T1) should be slightly shifted with some margin.

As a result of repeated various experiments, it was found that in the case of a normal load amount, a steady state is reached after 15 minutes have passed after the start of operation, so in this example, the time (T1) was set to 15 minutes. Therefore, when 15 minutes have passed after the start of operation, the drum outlet temperature and the dehumidifier outlet temperature, which had been constantly updated and stored in the RAM, are taken out and the difference between them is calculated.
The value is stored as a reference value (A) at another address in the RAM. After that, when the two measured temperatures reach (A+B) degrees, the drying operation ends and the machine shifts to cold air operation (turning off the heater (60) and blowing only air onto the clothes), but the start switch (75) is turned off. Let pressed B be 2℃,
When the start switch (91) is pressed, B is set to 5°C, and when the scoot switch (92) is pressed, B is set to 7°C. When B is 2℃, the drying operation ends at a drying rate of around 85%, when B is 5℃, the drying operation ends at a drying rate of around 95%, and when B is 7℃, the drying rate is 98%
The drying operation ends before and after. A dryness rate of around 85% means that the cloth is damp enough to iron, and a dryness rate of around 95% means that it hardly feels damp.

For this reason, when the start switch (75) is pressed, the drying operation ends in a state where ironing is possible, so it can be set to the ironing course, and when the start switch (91) is pressed, the drying operation course is set to the standard drying operation course. When the start switch (92) is pressed, a careful drying operation course can be started. Even if 150 minutes have passed since the start of operation and drying operation is still being performed, the operation will shift to cold air operation. This is for protection in case the temperature detection thermistor (61) (62) etc. breaks down.

After the drying operation is completed and the cold air operation is started, the first relay contact (79'
) and stop the motor (41) to end the cold air operation.

In the above embodiment, when the temperature difference between the drum outlet temperature and the dehumidifier outlet temperature reaches (A+B) degrees, the drying operation is stopped and the cold air operation is started.
The drying operation may be continued for a certain period of time after reaching +B).

In addition, in the above embodiment, the difference between the temperature before entering the dehumidifier in the circulating air path, that is, the temperature at the drum exit, and the temperature after passing through the dehumidifier in the cooling air path was measured. Instead of measuring the temperature after passing through the dehumidifier, a second heat sensitive element (62) may be provided at the position indicated by the dashed line in FIG. 3 (3) to measure the temperature after passing through the dehumidifier in the circulating air path.

Alternatively, the temperature difference before and after the dehumidifier in the circulating air path may be measured.

This is because the temperature difference here and the temperature difference explained earlier show similar changes. However, the temperature difference before and after the dehumidifier in the circulation air path is smaller than the temperature difference described above.

(F) Effects of the Invention According to the present invention, the temperature before passing through the dehumidifier in the circulating air path, the temperature after passing through the dehumidifier in the cooling air path, or the temperature after passing through the dehumidifier in the circulating air path. Since the drying time is controlled by measuring the difference between the two temperatures, the drying time can be controlled more accurately than measuring the difference between the temperature of the exhaust air from the drum and the outside temperature. Firstly, the outside temperature tends to become unstable when the dryer is used indoors, whereas the temperature after passing through the dehumidifier in the circulation air path or cooling air path remains constant and dry. This is because the state is almost constant and stable. Second, even if the circulating air volume fluctuates due to filter clogging or the power supply voltage fluctuates and the exhaust temperature from the drum changes, in the case of the present invention, the temperature of the exhaust gas from the drum changes. The temperature after passing through the dehumidifier in the circulation air path or cooling air path also changes, and the temperature difference is almost the same in any case.

As described above, the present invention is advantageous in that it detects a constant drying rate and terminates drying without being influenced by external factors such as outside air temperature or the amount of load. This is especially convenient when applying ironing, as it is possible to detect the drying rate desired by the user and then terminate the drying process.

[Brief explanation of drawings]

The drawings show the present invention, and Fig. 1 is a front view of the circulating clothes dryer, Fig. 2 is a rear view of the same with the back plate removed, and Figs. 3 and 4 are the parts shown in Fig. 1. 5 is a control circuit diagram, 6 is a variation curve of the temperature difference between the drum outlet temperature and the dehumidifier outlet temperature, and 7
The figure is a flowchart. (6) Drum (drying room), (48)...Dehumidifier, (60
)...Heater, (61)...First heat sensitive element (heat sensitive means), (62)...Second heat sensitive element (heat sensitive means), (72
)(73)...Voltage comparator, (74)...Ladder circuit, (67)...Microcomputer (storage means, control means), (75)(91)(92)...Start switch (change) means). Figure 1 -□ Figure 3 Figure 6 Figure 7

Claims (1)

[Claims] (1) In a circulating clothes dryer having a circulating air passage in which exhaust air from a drying room is cooled with a dehumidifier to remove moisture, reheated with a heater, and then supplied to the drying room, the a first heat-sensitive means for measuring the temperature of the air passing through the dehumidifier; and a cooling air passage for cooling the air after passing through the dehumidifier in the circulation air passage or by applying outside air to the dehumidifier. When the difference between the temperature measured by the second heat-sensitive means that measures the temperature of the air after passing through the dehumidifier and the temperature measured by both heat-sensitive means reaches a substantially constant value after a predetermined period of time has elapsed from the start of operation. A storage means for storing the temperature difference as a reference value, and a control means for terminating the drying operation when the measured temperature difference reaches a predetermined value or more than the stored reference value or after a certain period of time has elapsed thereafter. and a changing means for changing the predetermined value to an arbitrary size.