JPS58146398A - Drier - 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 invention relates to a dryer that is economical and can contribute to energy savings.

More specifically, the invention comprises a heat source section using gas, oil, or electricity, a drying section for drying objects to be dried, and a ventilation section for exhausting dry exhaust gas containing water vapor. This system automatically controls the operating status of the dryer based on the detection signal from the moisture element.It not only contributes to energy saving when operating the dryer, but also helps with ironing immediately after drying and creating a suitable texture when drying clothes. The purpose of the present invention is to provide a dryer with new functions such as a drying tube that enables high value-added drying.

Generally speaking, in order to dry things quickly, the higher the temperature, the lower the ambient humidity, and the higher the wind speed, the better.These three conditions are used as drying conditions. However, in general, when designing a dryer, due to the lack of a suitable humidity detection element, consideration must be given to the drying temperature difference and wind speed, and a dryer that uses humidity control has not yet been released.

Next, using a household washing machine and an electric rotary clothes dryer, a conventional example and an uninvented example will be compared and explained.

Generally, clothes that have been washed and dehydrated in a washing machine etc. are
When drying by blowing hot air, the temperature of the so-called exhaust gas that passes through the material to be dried becomes as shown in FIG. That is, the temperature rises corresponding to the start-up period of the heater that is the heat source, the area B where the heat exchange between the moisture in the clothes and the hot air is maintained at equilibrium, and the so-called constant rate drying occurs. After passing through region B, the clothes are divided into three regions: region B, where lapse rate drying occurs, and region C, where the temperature of the clothing gradually increases. For example, considering the relationship between the degree of dryness of clothing and the temperature range 2, it is a necessary condition that the exhaust gas temperature falls within range C. However, any position in area C is not sufficient, and due to the relationship with the amount of clothing that is loaded at once,
Even in area C, there was some moisture remaining in the seamed parts and thick parts, and on the contrary, although it was dry, it was in a state where it was dried too quickly.

Considering this, when drying clothes, it is extremely difficult to automatically operate the dryer by detecting only temperature and achieve a degree of dryness with appropriate airflow.

Conventional clothes dryers rarely operate automatically using humidity sensors due to the reasons mentioned above and the fact that suitable moisture-sensitive sensing elements have not yet been developed. Hourly operation with manual timer settings is the mainstream. However, this method causes some disadvantages as follows.

0) Depending on the type of clothing that will be loaded, 1. The operating time must be set based on the user's experience and intuition. In this case, over-drying or under-drying as described above is likely to occur.

■ From the point of view of energy saving, it is undesirable to continue operating even though drying has already been completed. In addition, excessive drying can cause the clothes to deteriorate and the texture of the clothes to be lost.

■ It is said that the best dry finish is one that can be ironed immediately after drying is finished, but it is difficult to achieve this condition.
:, It is almost impossible to do this only by setting the timer.

■ The seams and thick clothing end up drying even though they are not yet dry.

In order to solve these problems, a type of dryer that detects the wetness of the material to be dried and automatically turns the dryer to its side has been proposed and is now commercially available. FIG. 2 shows its basic configuration.

Figure 2 shows the cross-sectional structure of a clothes dryer using a nichrome wire heater or a semiconductor heater with positive resistance-temperature characteristics as a heat source (hereinafter simply referred to as a heater), where 1 is an incorporeal outer frame, 2 is a main body front plate, and 3 is a clothes dryer. numeral 4 is a rotating drum for storing the material to be dried; numeral 4 is a heater mounting plate; a heater 6 is provided between the main body front plate 2 and a heater mount 5; Reference numeral 7 denotes a door that can be opened and closed at the opening I'' part of the main body front plate 2 into which clothes are put, and has an intake port 2L on a part of its outer periphery for inhaling outside air. 8 is a fan for blowing air, and the power of the motor 9 is supplied to the belt 1.
Rotation is transmitted by o. Similarly, the rotating drum 3 is
The power of the motor 9 is transmitted through the belt 11, thereby driving the motor. 12 is a filter for collecting cotton waste.

Reference numeral 13 indicates an intake port provided on the front wall of the rotating drum 3 so as to communicate with the heater 6, and 14 indicates a clothing input port provided in the rotating drum 3.

Reference numeral 16 denotes an exhaust port, which is provided in the exhaust section 16 connected to the drying section made up of the rotating drum 3. 17.18 is rotating drum 3
A pair of conductive electrodes provided on the inner wall of the

Furthermore, in order to compare the effects of the invention, a humidity sensor 19 is placed on the inner surface of the door 7 to detect the humidity inside the rotating drum 3, which is a drying section. A thermocouple hygrometer is also installed. In addition, a humidity sensor 20 for detecting the humidity of the exhaust section 16 is disposed near the exhaust gas [116] of the exhaust section 16, and a thermocouple hygrometer is also installed in the vicinity of the exhaust section 116.

To explain the operation of the clothes dryer having the above configuration, the air heated by the heater 6 is guided into the rotating drum 3 by the air intake [113] provided on the heater mounting plate 4 by the blower fan 8, and is then guided into the rotating drum 3 by the air intake [113] to be dried. The material to be dried is completely dried by contacting with the material and exchanging heat, and then introduced into the exhaust section 16 through the filter 1271. During this time, the moisture contained in the material to be dried is contained in the exhaust gas as water vapor, passes around the humidity sensor 19 installed inside the exhaust port 15, and exits the exhaust gas from the exhaust port 15. Exhaust the air outside.

A method for detecting the end of drying in a conventional rotary drum type dryer will be described. When the rotary drum 3 rotates, the object to be dried comes into contact with the conductive electrodes 17 and 18. When the moisture content of the dried material is large, a short circuit occurs between the conductive electrodes 17 and 18 due to the conductivity of the moisture, but as the dried material is dried, the apparent conductivity of the dried material decreases. decreases, and the resistance between them when they contact the conductive electrodes 17, 18 gradually increases. This resistance value is fixed in advance, and the magnitude relative to this fixed resistance value is automatically detected to automatically operate the dryer. This type of dryer has superior characteristics compared to the timer-set type dryer, and solves the problems ① and ② mentioned in AiT. Achieving dry texture and dry texture are not always solved.

When drying clothes, we pay attention to the amount of moisture contained in the clothes as one of the indicators of how wet they are.

Weight of clothes before washing W1, weight of clothes after washing and dehydration W2
, the weight of the clothes after drying @W6 is the ideal finished state, but in reality, the folded parts of sleeves and collars are -
Since the drying speed is slower than that of the batter, a change in water weight is required. In the above-mentioned wetness detection type automatic dryer, the fixed resistance value to be set is determined using this value as a guide.

When the drying method shown in formula (2) is carried out, the part of the clothing becomes too dry and becomes dry. It is difficult to obtain an appropriate degree of dryness only by detecting the degree of wetness.

In view of the above-mentioned circumstances, the present invention has been devised to detect the relative humidity, absolute moisture content, temperature, etc. of drying exhaust air and automatically control it from the two viewpoints of achieving optimal drying and texture, and saving energy. The dryer to be operated is one with 1>% concentration, and the non-invention will be specifically explained below based on Examples.

0 Figure 3 shows the exhaust temperature a of the dryer 71) and the exhaust temperature l of the same exhaust.
↑ Moisture scale and relative humidity C are shown against the start force and time. As shown in Figure 1, the exhaust gas temperature 2L is divided into three regions (A, B, and C).The absolute moisture meter gradually increases in the temperature rising region and remains constant in the constant rate drying region. 9. The lapse rate gradually decreases in the dry region.As a result of the ratio of the rate of increase in temperature to the rate of increase in absolute moisture content, the relative humidity Indicates the descent following the raid.

In the constant rate drying region, the relative humidity C becomes a little low, and after this period, the relative humidity C gradually decreases.

FIG. 4 shows the cross-sectional structure of the humidity sensors 19 and 20 in FIG. 2. This element (dl tantalum.

A valve metal base 21 such as titanium or aluminum, a dielectric anodic oxide film 22 on this valve metal base 21, and a semi-containing material such as manganese dioxide present in contact with a part of the soil of this dielectric anodic oxide film 22. Basically, it consists of a conductive metal oxide layer 23 and a water vapor permeable conductive electrode 24 on the semiconductive 1'Ag metal oxide layer 23.
It is fixed to a metal case 27 having a diameter of 6.

28 is a glass hermetic seal, and the anode lead 2
9. Electrostatic capacitance is output from the cathode lead 30.

Figure 6 shows the relative humidity-capacitance characteristics of the above element.
It also has some temperature dependence as shown by the broken line in the figure.

That is, characteristic a is for the case where the temperature is 25°C, characteristic A is for the case where the temperature is 10°C, and characteristic C is for the case where the temperature is 40°C.

FIG. 6 shows another embodiment of the humidity sensor 19, 20, which is also equipped with a thermistor element for temperature measurement. That is, it basically consists of an element 31 shown in FIG. By using an element with this structure, it becomes possible to perform temperature compensation on the output of the humidity sensing element, for example, and more efficient automatic operation becomes possible.

Next, we will discuss specific effects. As the humidity sensors 19 and 20 of the dryer shown in FIG. 2, a tantalum humidity sensing element and a thermocouple thermometer shown in FIG. 4 were used.

The rotary drum type clothes dryer has a built-in semiconductor heater with an output of 1.25 kW and positive resistance temperature characteristics as a heat source, and can dry 11 pieces of drying material, approximately 2.2 kg.
Use tj that has been made to contain sufficient water and then dehydrated. The experimental results are described below.

Figure 7 shows the drying time, the humidity sensor 20, which is an exhaust humidity sensing element installed inside the exhaust port, and the rotating drum, which is the drying section, under the conditions of room temperature 22 degrees Celsius, water temperature 8 degrees Celsius, and indoor relative humidity 38 degrees. 3 shows the change over time of the relative humidity during drying obtained with the humidity sensor 19 which is a humidity detection element for the drying section provided on the inner surface of the door facing inward, and characteristic a is the humidity sensor 19. In the case of 2o, the characteristic is that of the humidity sensor 19.

As is clear from Fig. 7 (71), the relative humidity rises rapidly in both the drying section and the exhaust section as soon as drying starts. 1
From 0 minutes to 26 minutes, both the drying section and the exhaust section show a constant value of 3, meaning constant rate drying, but after 25 minutes, the relative humidity in the drying section begins to drop slowly.

However, the relative humidity at the exhaust port remained constant for 55 minutes,
After 60 minutes, the relative humidity at the exhaust port suddenly drops to 70 minutes.
After a few minutes, the relative humidity in the drying section and the exhaust section will be close to each other or at the same value. Although not shown in Figure 7,
When the relative humidity at the exhaust port suddenly drops, the temperature of the exhaust gas will rise rapidly in inverse proportion to the relative humidity.

If ironing is required immediately after drying, it is preferable to finish at a relative humidity of about 70 to 75%. If you want to perform complete drying, either give a signal to turn off the power when the relative humidity is below 60 coefficients, or compare the relative humidity between the drying section and the exhaust section with a comparator and use the same value or a value similar to this value. It is also possible to set it to synchronize with the power off signal when the power is turned off.

Next, under the same conditions as when obtaining the characteristics shown in Fig. 7, 11 pieces of paper were dehydrated using a centrifugal dehydrator of approximately 2.2 kqf, then placed in a dryer, and the relative humidity of the exhaust port was set to 40 to 95 degrees. FIG. 8 shows a case in which the aperture area of the exhaust port was adjusted as much as possible, and the relationship between the relative humidity of the exhaust port, the time required for drying, and the power consumption required for drying was determined. In the figure, characteristic a is related to drying time, and the characteristic is power consumption (KWH)/dry material 2.2 (k
/).

As is clear from Figure 8, 71=, even at a relative humidity of 95%, it is possible to dry with a truly dry texture, and the surprising fact is that the power consumption required for drying is the most economical. found. However, if the relative humidity is high humidity exhaust drying such as 96%, the drying time will be approximately twice as long.

On the other hand, as can be seen from Figure 8, if the relative humidity at the exhaust port is 65% or less, the drying time will be short, less than 60 minutes, but the electricity required for drying will be abnormally high. Not only is this not a good shelter from an energy-saving perspective, but the power capacity of the heater in the heat source section must be set to 1.25 KW or more in a dry area where the relative humidity at the exhaust port is less than 55% to achieve the purpose. become unable.

15 Therefore, the relative humidity of the exhaust port will cause the dryer to be turned on the automatic side.
To do so, take into consideration the drying time, drying heat source capacity, energy efficiency during drying, etc., and set the relative humidity of the exhaust gas at the exhaust port as the optimal drying condition, excluding special items such as paper, clay, cake, etc. The operating status is 55-95% on the automatic side (goods)
It's good to do that.

Next, using the same drying conditions used to obtain the characteristics shown in Figures 7 and 8, the maximum flow rate from the heat source for drying until the air is introduced into the drying area is vs, and when the air exits the drying area, If the maximum flow velocity at iA8 of the exhaust section leading to the exhaust port is vE, vs is the flow velocity at the intake air [113] to the drying section, which is usually a rotating drum, and VE is the flow velocity at the exhaust port. FIG. 9 shows the correlation between the ratio of maximum flow velocity (E) in the exhaust section/maximum flow velocity (vs) in the heat source section and the power consumption required to dry the material to be dried.

In Fig. 9, setting the ratio of vE/vs to 100% follows a tendency to make the wind pressure in the drying part 100%, and therefore, when vs is constant, the VE at the exhaust port of the exhaust section
When the temperature is set to K, the drying temperature in the drying section becomes high, the relative humidity at the exhaust port also becomes high, and the power consumption required for drying tends to become small.

According to FIG. 9, when the ratio of Vx/Vs is 161 or less (C), the power consumption becomes low, and when the ratio of vZ/vs is 1.1 or more, the power consumption during drying decreases. In other words, it is easy to understand that energy saving is possible.

In addition, in the non-example, 9 explanations were made using the case where the invention was applied to a clothes dryer, but the invention could also be applied to other dryers, such as a dish dryer or a commercial dryer. Needless to say, it is possible to expand.

As described above, according to the invention, the humidity sensor is used to detect the relative humidity of the exhaust part, and the automatic operation is performed based on the relative humidity signal. In particular,
In addition, it is possible to provide a dryer that has a new function that is not available in conventional VCs, allowing efficient drying and arbitrarily adjusting the drying air flow.

[Brief explanation of the drawing]

7 Figure 1 is a diagram showing the relationship between drying time and exhaust temperature of a general dryer, Figure 2 is a longitudinal cross-sectional view of the dryer, and Figure 3 is a diagram showing the temperature and absolute moisture content of the exhaust air from the dryer. Fig. 4 is a cross-sectional view showing a humidity sensor for a dryer in an embodiment of the invention, and Fig. 5 South is a diagram showing the relationship between relative humidity and capacitance of the same humidity sensor. , FIG. 6 is a sectional view showing all other embodiments of the same temperature sensor, FIG. 7 is a diagram showing the relationship between drying time and relative humidity in the drying section and exhaust section in the case of the non-invention, and FIG. A diagram showing the relationship between relative humidity, drying time, and power consumption in the exhaust air [1] of the exhaust section, Fig. 9 shows the maximum flow velocity vE at the exhaust section and the maximum flow velocity v at the heat source section.
FIG. 3 is a diagram showing the relationship between the ratio of s and power consumption. 3... Rotating drum (drying section), 6... Heater (heat source section), 16... Exhaust port, 16...
...Exhaust section, 19.20...Humidity sensor. Name of agent Patent attorney Toshio Nakao 1 person (Fig. 2) Kazumo Ku (Fig. 4) 5J0 20 /
θd No. 61 8th phase, Ritsu “I” (≧ 5- Fig. 9

Claims (6)

[Claims] (1) A heat source section that uses gas, oil, or electricity as a heat source and supplies heated air, a drying section that stores the material to be dried and dries the rack, and exhaust gas containing water vapor from this drying section to the exhaust port. What is claimed is: 1. A dryer comprising: an exhaust section that guides humidity; the dryer is configured to detect relative humidity with a humidity sensor provided in the exhaust section and control the operation of the dryer. (2) The dryer according to claim 1, which is configured to perform drying operation at a relative humidity of 55% to 96% and to stop drying operation at a relative humidity of 50% or less. (3) Let the maximum flow velocity of hot air in the heat source section be vs, and the maximum flow velocity in the exhaust section be vE, then set the maximum flow velocity in the exhaust section so that the vX//vsO ratio is 1.1 or more. Claim 1 or 2 for dry driving as a dog
Dryer as described in section. (4) Let TD be the average temperature of the drying section during the constant rate drying period,
In any of claims 1 to 3, the exhaust temperature during the constant rate drying period at the detection part provided in the exhaust part is T, and the TD-TE21 is set to 5°C. Dryer listed. (5) Claims 1 to 4 configured to control the output of the heat source section based on the relative humidity detected in the exhaust section.
The dryer described in any of the paragraphs. (6) The humidity sensor includes a dielectric anodic oxide film, a semiconductive metal oxide layer existing in contact with a portion of the dielectric anodic oxide film, and a second semiconductive metal oxide layer. A dryer according to any one of claims 1 to 5, comprising a water vapor permeable conductive electrode.