JPS5815899A - Apparatus for detecting drying degree in garment 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 The present invention mainly relates to a rotary drum type clothes dryer, and more particularly to a device for detecting the degree of dryness based on the temperature difference between intake air temperature and exhaust air temperature.

First, the structure of a rotary drum type clothes dryer will be explained with reference to the principle diagram shown in FIG. Reference numeral 1 denotes clothing, which is the item to be dried; 2, a rotating drum that stores the clothing 1; 3, a fan for blowing air into the rotating drum 2; and 4, a fan 4 rotates the fan 3 and at the same time controls the rotating drum 2 via a deceleration means. 5 is a heater that heats the suction air and turns it into hot air; 6 is an arrow indicating the flow of suction air (which has the same temperature as the ambient temperature outside the machine); 7 is a Arrow 8 indicates the flow of hot air, 8 indicates the flow of hot air that has contributed to drying, that is, exhaust air. 9 indicates an intake-side temperature-sensitive resistance element whose resistance value changes in accordance with the temperature of intake air (intake air temperature). , 10 is an exhaust-side temperature-sensitive resistance element whose resistance value changes in accordance with the temperature of the exhaust air (exhaust temperature). In such a rotary drum type clothes dryer, the clothes 1 are dried by loosening the clothes 1 by rotating the rotating drum 2 and bringing the clothes 1 into contact with hot air.

FIG. 2 is a diagram showing the relationship between the elapsed time of the drying operation, the temperature difference between the intake air temperature and the exhaust air temperature, and the dryness of the clothes. The solid line a shows the change in the dryness of the clothes, and the dryness is It is obtained by the following formula.

Weight of clothes before washing Dryness (%) = X100 M lid during drying of clothes On the other hand, the solid line indicates the change in the temperature difference between intake air and exhaust air. As can be seen from Figure 2, this temperature difference usually widens to about 10 degrees at the beginning of the drying operation, and then remains constant until 1, when the moisture contained in the clothes decreases to a certain extent. When the moisture content decreases, it becomes larger due to the sudden rise in exhaust temperature.
When the temperature reaches about 27.5deg, the dryness of the clothes is 1.
00%.

Therefore, when the difference in degrees between the intake air temperature sensed by the intake side temperature sensing resistance element 9 and the exhaust temperature sensed by the exhaust side temperature sensing resistance element 10 reaches about 27.5 degrees, the notification means is activated or the drying temperature is If the operation is terminated, the clothes can be dried to 100% dryness, but in reality, there are various problems.

Generally, during the drying operation, the rotation of the rotating drum 2 causes the clothes 1 to dry.
There is no problem if the mixture is well stirred, but if the
If it adheres to the inner surface of the rotating drum 2 or if the clothes 1 become entangled and bunched up in one place, the contact between the hot air and the clothes 1 will be poor, and the exhaust temperature will temporarily rise dramatically, causing the intake air temperature to drop. The temperature difference with the exhaust gas temperature temporarily widens as shown by the broken line in FIG.

In such a case, if the notification means is activated or the drying operation is terminated when the temperature difference between the intake air temperature and the exhaust air temperature reaches 27.5 degrees, for example, at point G in Fig. 2, If the temperature difference temporarily reaches 27.5 degrees and detects this, the notification means will notify that the dryness is 100% or end the drying operation, etc. even though the dryness of the clothing 1 is 90%. This has the disadvantage of causing malfunction.

The present invention has been made in view of this point, and is designed to operate the notification means or the drying operation stop means when the temperature difference between the intake air temperature and the exhaust air temperature exceeds a predetermined temperature difference and this state continues for a certain period of time. This is designed to prevent malfunctions caused by temporary temperature differences.

The embodiment of the present invention shown in FIGS. 3 to 5 will be described in detail below.

First, in the electric circuit shown in FIG. 3, the electric circuit includes an intake side temperature sensitive resistance element 9, an exhaust side temperature sensitive resistance element 10, a power supply circuit section 11, a dryness 100% determination circuit section 12, and a dryness 90%.
It is composed of a determination circuit section 13, a dryness 100% notification circuit section 14, a dryness 90% notification circuit section 15, a buzzer notification circuit section 16, and the like.

The power supply circuit section 11 includes a diode 18, a resistor 19.20, and a constant voltage diode 2 between both terminals of a commercial AC power supply 17.
1 is connected in series, and a capacitor 22 is connected in parallel to the series circuit of a resistor 20 and a constant voltage diode 21. The constant voltage diode 21 includes a series circuit of temperature sensitive resistance elements 9 and 10, and resistors 23 and 24.
．． Twenty-five series circuits are each connected in parallel relationship. Note that the temperature-sensitive resistance elements 9 and 10 have negative characteristics.

The dryness 100% determination circuit section 12 determines that the dryness is 100% when the temperature difference between the intake air temperature and the exhaust air temperature is 27.5 degrees or more and this state continues for a certain period of time. In the dryness 100% determination circuit section 12,
26 connects the + side input terminal to the connection point C between resistors 23 and 24,
- comparators whose input terminals are respectively connected to the connection point A between the temperature-sensitive resistance elements 9 and 10;
6, a resistor connected between the output terminal of the constant voltage diode 21 and the cathode of -21, 28 a resistor connected between the cathode and anode of the constant voltage diode 21 via a resistor 26, and 30
The positive input terminal is connected between the resistors 28 and 29, and the negative input terminal is connected to the output terminal of the regulator 26 through the diode 31. This is a capacitor connected between input terminals.

Incidentally, the output of the comparators 26 and 30 becomes H level when the potential of the + side input terminal becomes higher than the potential of the one side input terminal.

The dryness 90% determination circuit section 13 determines that the dryness is 90% when the temperature difference between the intake air temperature and the exhaust temperature is 20 degrees or more and this state continues for a certain period of time. In 13, 34 is a comparator whose + side input terminal is connected to the connection point B between the resistors 24 and 25, and the - input terminal is connected to point A, respectively, and 35 is a shimparator.
A resistor 36 is connected between the output terminal of 34 and the cathode of the constant voltage diode 21, the + side input terminal of 36 is connected between the resistors 28 and 29, and the - input terminal is connected to the output terminal of the comparator 34 via the diode 37. Comparator to connect, 3
8 forms a parallel circuit with the resistor 39 and connects the constant voltage diode 2
This is a capacitor connected between the anode of No. 1 and one input terminal of the comparator 36. In addition, comparator 34.
36 outputs an H level when the potential of the + side input terminal becomes higher than the potential of the one side input terminal.

In the dryness 100% notification circuit section 14, 4° is a resistor connected between the cathode of the constant voltage diode 21 and the output terminal of the comparator 30, and 41 is connected in series with the resistor 42 and connected between the anode of the constant voltage diode 21 and the comparator. rater 3
The resistor 43 is connected between the output terminals of 0 and 43, the collector is the resistor 44, the light emitting diode 45 is interposed in series to the cathode of the voltage regulator diode 21, the pace is between the resistors 41 and 42, and the emitter is the voltage regulator diode 21. The transistors are connected to the anodes of the respective transistors.

In the dryness 90% notification circuit section 15, 46 is a resistor connected between the cathode of the constant voltage diode 21 and the output terminal of the regulator 36, and 47 is connected in series with the resistor 48 to serve as the anode of the constant voltage diode 21. Comparator 3
A resistor 49 is connected between the output terminals of the resistor 6 and the collector is the resistor 50, the light emitting diode 51 is interposed in series to the cathode of the voltage regulator diode 21, the pace is connected between the resistors 47 and 48, and the emitter is the voltage regulator diode 21. The transistors are connected to the anodes of the respective transistors.

In the buzzer notification circuit section 16, 52 is the comparator 3
Contact S1 comparator 36 connected to the output terminal of 0"
53 is a Nant gate circuit 54 formed by a CMO8 IC, and a manual selection switch for selectively connecting a switching piece to these contacts; Inverter 5 formed by
5, 56, resistors 57 to 59, a capacitor 60, and diodes 61 and 62. The multivibrator 53 has one input terminal of the Nant gate circuit 54 connected to the switching piece of the selection switch 52. 5(a) at the point when the input becomes H level.
Generates a voltage waveform as shown in .

63 is a Nant gate circuit 64 formed by CMO8 IC, an inverter formed by CMO8 IC: -6
5, 66, resistor 67, 68, and capacitor 69 - 170 is an inverter formed by a CMO8 IC whose input terminal is connected to the output terminal of inverter 66, and 71 is the output terminal of inverter 70 and a constant voltage diode. This is a piezoelectric buzzer connected between the anodes of 21 and 21. Therefore, the unstable multivibrator
Reference numeral 63 performs an oscillatory operation when the voltage at point D is at H level to generate a voltage waveform as shown in FIG. 5(b) at point E, causing the piezoelectric buzzer 71 to sound.

Next, its effect will be explained. Now, when the motor 4 and the heater 5 are energized with the clothes 1 stored in the rotating drum 2, the clothes 1 are agitated by the low speed rotation of the rotating drum 2, while the hot air generated by the fan 3 and the heater 5 is rotated. After entering the drum 2 and contributing to the drying of the clothes 1, it is discharged outside the machine, and the drying operation is performed as described above.

Immediately after the start of the drying operation, the temperature difference between the intake air temperature and the exhaust air temperature quickly rises to about 10 deg as shown in Figure 2. Because a large amount of heat is taken away by the evaporation of
Once the exhaust gas temperature rises to a certain degree, it does not rise any further, and therefore the temperature difference between the intake air temperature and the exhaust gas temperature does not increase beyond about 10 degrees, and as shown in FIG. 2, the temperature difference remains constant for a while. Of course, the degree of dryness of the clothing 1 gradually increases as shown by the solid line a in FIG.

On the other hand, the potential at the connection point between temperature-sensitive resistance elements 9 and 10, that is, point A, changes as shown by the solid line in FIG. At the beginning of the drying operation, the potential is lower than that at point B and point C. However, comparator 26.34
Since the potential of the + side input terminal is higher than the potential of the one side input terminal, the output is at H level, and the capacitor 32.38
At the same time, the potential of one side input terminal of the comparator 30, 36 is made higher than the potential of the + side input terminal, and its output is kept at L level.

As time passes from the start of the drying operation and the degree of dryness of the clothing 1 reaches approximately 80%, the amount of moisture contained in the clothing 1 decreases and the amount of heat taken away by the evaporation of moisture decreases. The temperature rises rapidly, widening the temperature difference with the intake air temperature, and the potential at point A also rises as the resistance value of the temperature-sensitive resistance element 10 changes in accordance with the change in the exhaust temperature. When the degree of dryness of the clothing 1 reaches 90%, the temperature difference between the intake air temperature and the exhaust air temperature becomes 20 degrees, and the potential at point A increases to the potential at point B. Then, the output of the comparator 34 becomes the ULV level, the charge in the capacitor 38 is discharged through the resistor 39, and the potential of the one side input terminal of the comparator 36 gradually decreases, and the L level state of the comparator 34 remains for a certain period of time. (For example, 2
minute), the potential of the one side input terminal becomes lower than the potential of the + side input terminal, and the output becomes H.
level, turning on the transistor 49 and lighting the light emitting diode 51.

In other words, the dryness 90% determination circuit section 13 does not operate until the temperature difference between the intake air temperature and the exhaust air temperature becomes 20 degrees or more (the potential at point A is greater than or equal to the potential at point B) and this state continues for 2 minutes.
It is determined that the degree of dryness of the clothing 1 has reached 90%, and the light emitting diode 51 is turned on to notify the user that the degree of dryness has reached 90%. In addition, dryness level 9
0% is a wet state suitable for ironing.

Now, if the dryness level reaches 90%, the clothes 1
If the contact between the clothing 1 and the hot air deteriorates due to unevenness of As shown by the broken line in FIG. 4, the voltage also temporarily rises above the potential at point B, and accordingly, the output of the comparator 34 becomes L level and the discharge of the donor v-y capacitor 3B is started. However, the sudden rise in exhaust temperature is temporary, and within a relatively short period of time (within 2 minutes) the temperature difference will drop to 20deg or less, and the potential at point A will again become lower than the potential at point B. The output of the comparator 34 becomes H level again, and charging of the capacitor 38 is resumed. Sokuchi, comparator 3
41'! When the output eL level is temporarily toggled, the output is inverted again to H level before the output of the comparator 36 is inverted to H level, so there is no possibility of making an erroneous determination that the degree of dryness is 90%, and therefore the light emitting diode 51 will not turn on when the temperature difference between the intake air temperature and the exhaust temperature temporarily exceeds 20 degt.

When drying progresses under normal conditions and the degree of dryness reaches 100%, the temperature difference between the intake air temperature and the exhaust air temperature is 27.5, and the potential at point A rises to the potential at point 0. Then, the output of the comparator 26 becomes L level, and the electric charge of the capacitor 32 is discharged through the resistor 33, and the output of the comparator 32 is discharged through the resistor 33.
When the potential of the one side input terminal of 0 is gradually lowered and the negative level state of the comparator 26 continues for a certain period of time (for example, 2 minutes), the potential of the one side input terminal of the comparator 30 becomes the + side input. The potential becomes lower than the terminal potential and the output becomes H level, turning on the transistor 43t and lighting the light emitting diode 45.

In other words, the dryness 100% determination circuit section 12 detects the clothes when the temperature difference between the intake air temperature and the exhaust air temperature becomes 27.5 deg or more (the potential at point A is more than the potential at point 0) and this state continues for 2 minutes. It is determined that the dryness level of No. 1 has reached 100%, and the light emitting diode 45 is turned on to notify the user that the dryness level has reached 100%.

Now, if before the degree of dryness reaches 100%, the temperature difference between the intake air temperature and the exhaust air temperature temporarily becomes 27.5 degrees or more due to unevenness of clothing 1, etc., the potential at point A will also change as shown in Figure 4. As shown by the broken line, the potential temporarily rises above the zero point, and as a result, the potential of the comparator 26. The output of , is L
Level Kl) Discharging of the capacitor 32 is started. However, since the sudden rise in exhaust temperature is temporary, like the 90% dryness determination circuit section 13 described above, the comparator 26 is activated before the output of the comparator 30 inverts to the H level (2 Within minutes), the output is reversed to H level again and charging of the capacitor 32 is restarted, thereby preventing an erroneous determination that the degree of dryness is 100%. Of course, the light emitting diode 45
does not light up.

Next, the buzzer notification circuit section 16 is selected and used by the user. For example, if the selection switch 52 is connected to contact t (switching), when the output of the comparator 36 becomes H level, the unstable multivibrator is activated. -53 operates to generate a voltage waveform as shown in Figure 5(a) at point D, which causes the unstable multivibrator -63 to operate and generate a voltage at point E as shown in Figure 5(b). By generating the waveform, the piezoelectric buzzer 71 sounds "beep, beep, beep...".

That is, the fact that the degree of dryness has reached 90% is notified by lighting the light emitting diode 51 and sounding the piezoelectric buzzer 71.

Also, change the selection switch 52 to the contact S and make a clutter.
When the output of the comparator 30 becomes H level and the device dies, the piezoelectric buzzer 71 sounds as described above, and the light emitting diode 45
0 to notify that the degree of dryness has reached 100% by lighting the 0. In the above-described embodiment, notification by the light emitting diode 45, 51 and notification by the piezoelectric buzzer 71 are used together, but one of them may be omitted. It's okay. Furthermore, when the degree of dryness reaches 90% or 100%, it is possible to operate a relay or the like to cut off power to the heater and motor and automatically terminate the drying operation. In addition, the present invention is not limited to the configuration of the above-described embodiment, and any other configuration may be used as long as it does not depart from the gist of the present invention.

As described above, according to the present invention, the dryness determination means operates the notification means or the drying operation stop means when the temperature difference between the intake air temperature and the exhaust air temperature exceeds a predetermined temperature difference and this state continues for a certain period of time. By being equipped with this function, the degree of dryness can be accurately detected without causing malfunctions when the temperature difference between the intake air temperature and the exhaust air temperature temporarily exceeds a predetermined temperature difference due to things such as clothing being unevenly placed. It is extremely excellent in practical use.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the principle of the clothes dryer, Figure 2 is a diagram showing the elapsed time of the drying operation, the temperature difference between the intake air temperature and the exhaust air temperature, and the relationship between drying r of clothes, and Figure 3 is the apparatus of the present invention. FIG. 4 is a diagram showing voltage changes in the main parts of the circuit, and FIG. 5 is a voltage waveform diagram of the main parts of the circuit. 2: Rotating drum, 3: Fan, 4: Motor, 5: Heater, 9: Intake side temperature sensitive resistance element, 10: Exhaust side temperature sensitive resistance element, 12: Dryness 100% determination circuit, 13: Dryness 9
0% judgment circuit section, 14: Dryness 100% notification circuit section, 1
5: 90% dryness notification circuit section, 16: Buzzer notification circuit section. Agent Patent Attorney Aihiko Fukushi

Claims (1)

[Claims] 1. Sensed by the intake side @resistance element whose resistance value changes according to the intake air temperature, the exhaust side temperature-sensitive resistance element whose resistance value changes according to the exhaust temperature, and both of the above-mentioned temperature-sensitive resistance elements. Dryness determination means for a clothes dryer, characterized in that it is equipped with a dryness determination means that activates a notification means or a drying operation stop means when the temperature difference exceeds a predetermined temperature difference and this state continues for a certain period of time. Detection device.