JP2706806B2 - Operation control method of textile drying equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an operation control method of a drying apparatus for drying various textile products such as clothes, and for example, a rotating drum type (tumbler type) clothes drying apparatus. The present invention relates to an operation control method employed in the above-described method.

<< Prior Art >> A rotating drum type clothes drying apparatus widely used in cleaning work has a structure as shown in FIG. In the figure, 1 is a rotating drum, 2 and 3 are supporting rollers for supporting the rotating drum 1, 4 is an electric motor for driving the rotating drum 1 via the supporting roller 2, 5 is an outer body of the apparatus, and 6 is an intake duct. , 7 are an exhaust duct, 8 is a heat exchanger installed at the inlet of the intake duct 6, 9 is a steam pipe to the heat exchanger 8, and 10 is a flow control valve of the steam pipe 9 (hereinafter referred to as "steam valve"). ,
Reference numeral 11 denotes a blower installed in the exhaust duct, and reference numeral 12 denotes a drive motor of the blower 11.

The outer drum 5 is provided with an opening for putting clothes 13 into the rotating drum 1. The rotating drum 1 is rotated with the opening closed, and dry air is blown into the rotating drum 1 by the blower 11. The clothes 13 are passed through and dried. A large number of through holes are formed in the peripheral wall of the rotating drum 1, and the intake air heated by the heat exchanger 8 passes through the rotating drum 1 through the through holes, is humidified, and is discharged from the exhaust duct 7. Is done.

Conventional operation control of such a drying apparatus is usually performed by a timer, and an operator sets an operation time based on experience in consideration of the amount of the clothes 13 put in, the moisture content, and the like, and the steam valve 10 In general, the operation is performed by adjusting the amount of heat given to the intake air by the method described above. As an attempt to improve such an all-experience-based method, a control method in which a humidity sensor is provided in the exhaust duct and the operation of the device is stopped when the humidity of the exhaust air falls below a predetermined value has been partially adopted. ing.

As another conventional means, the absolute humidity of the air sucked into the dryer body and the absolute humidity of the air blown out from the dryer body are measured, and when the difference between the two becomes less than a set value, the operation of the apparatus is started. A control method of stopping the operation has been proposed.

<< Problems to be Solved by the Invention >> The amount of moisture contained in the textile product 13 and the ease of drying differ depending on the type of fiber such as natural fiber, synthetic fiber, blended fiber, etc. It also depends on physical conditions such as. In the method of setting the operation time of the drying apparatus based on the conventional experience, it is necessary to set the time of the timer in consideration of such detailed conditions, and therefore, the apparatus cannot be operated without considerable experience. There are drawbacks. In addition, in such a method, the operation time is set to be longer, but if this is done, the textiles 13 are rubbed in the rotating drum 1 in an overdry state, and the fabric is damaged, and the work time is reduced. And the loss of heat energy is also large. Furthermore, there is a danger of fire or the like due to the generation of static electricity due to the rubbing in an overdry state.

If the control method of detecting the humidity of the exhaust air and stopping the operation of the device is adopted, the above problem may be solved. However, in practice, the drying condition is not always satisfactory in relation to the humidity of the outside air. And there is a risk that the humidity of the exhaust gas may be set lower than the humidity of the outside air to give a stop command when the humidity of the outside air is very high. There is.

The above drawbacks can be solved by a control method for detecting the difference between the absolute humidity of the outlet and the absolute humidity of the suction of the dryer body and stopping the operation of the apparatus. It is necessary to provide a humidity sensor for each of the discharge side, which increases the cost of the apparatus.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and stops a device by detecting a drying state of a textile product in the device more accurately with only a humidity sensor provided on an exhaust side. It is another object of the present invention to obtain a control method capable of controlling the operating conditions over time in accordance with the quantity and quality of the textile product to be dried, and to reduce the time required for consuming clothes and the like without wasting energy. It is an object of the present invention to obtain an operation control method capable of drying the oil.

<< Means for Solving the Problems >> According to the present invention, a method in which the measured values of the humidity sensors 26 and 29 attached to the exhaust duct 7 of the drying device before the start of the drying step are used as the measured values of the outside air humidity, and the humidity sensor The above problem has been solved by adopting a method of updating the minimum value during the operation cycles 26 and 29 as the measured value of the outside air humidity.

And the absolute humidity M of the discharged air during the operation of the drying apparatus.
Is detected over time, and a control method of stopping the drying device when the deviation between the detected value and the absolute humidity Mo of the outside air measured by the above-described method reaches a set value is adopted,
Further, a control method of detecting the absolute humidity M of the discharged air with time and controlling the amount of heat of the heating device 8 and the amount of air of the blower 11 by a differential signal or a difference signal M-Ma in relation to the signal at the time of the previous measurement. Is adopted.

<< Operation >> FIG. 5 is a graph schematically showing the relationship between the elapsed time P from the start of drying and the absolute humidity M in the discharged air, and FIG. 3 is a graph schematically showing the relationship. Mo is the absolute humidity of the outside air, the curve shown by the imaginary line is when the absolute humidity of the outside air Moh is high, and the drying time is longer than when the humidity is low.

In the rising period A immediately after the start of the drying, the heat of the intake air is consumed for increasing the temperature of the moisture impregnated in the clothes 13 and the like, and the humidity T of the exhaust air increases with this temperature increase. In the steady period B, the exhaust temperature T and the absolute humidity M of the exhaust air become substantially constant, and the drying proceeds with the supply heat amount and the evaporation amount being balanced. When the moisture contained in the clothes and the like decreases, the heat utilization efficiency starts to decrease, the exhaust temperature T increases, and the absolute humidity M of the exhaust decreases (decay period C). The absolute humidity M of the exhaust is the absolute humidity of the outside air
Never lower than Mo.

In the method of the present invention, the outside air humidity is measured or updated by the humidity sensors 26 and 29 provided in the exhaust duct 7 of the drying device, and the absolute humidity M of the exhaust gas detected with time during the drying process is measured or updated. The ratio of the difference ΔM between the absolute humidity Mo of the outside air and the absolute humidity M of the exhaust to the absolute humidity Mo of the outside air (Mmax−M)
The operation of the drying device is stopped when / (Mmax-Mo) reaches a set value. Thus, by providing the humidity sensor only in the exhaust duct, a desired dry state can be obtained without being affected by the level of the outside air humidity.

Further, the absolute humidity M of the exhaust gas is detected over time, and a differential or difference signal thereof is detected from the rising period A to the stationary period B,
Further, since the shift to the decay period C can be detected,
For example, in the rising period A, the amount of heat applied to the intake air and the amount of air from the blower are maximized, in the steady period B, the amount of heat is reduced, and during the decay period C, the amount of heat and the amount of air are sequentially reduced according to the decrease in humidity. By doing so, clothes and the like can be dried in a short time without wasting energy.

<< Embodiment >> FIG. 1 is a flowchart of a first embodiment of the method of the present invention, and FIG. 2 is a hardware configuration diagram in that case. In FIG.
20 is a control device, 21 is a CPU, 22 is an input interface, 2
3 is an output interface, 24 is a memory, and 25 is a setting device. 26 is a humidity sensor, 27 is a temperature sensor, and these are installed in the exhaust duct 7 of the drying device. 28 is a blower 11
Is an inverter for controlling the rotation of the motor. The humidity sensor 26 is a sensor for detecting relative humidity. A humid air chart is registered in the memory 24, and the value of the humidity difference ΔM (see FIG. 5) when the apparatus is stopped is stored in the setter 25. Is set.

Referring to FIG. 1, before starting the drying process, a blower 11
And the outside air is led to the exhaust duct 7, and the measured values of the humidity sensor 26 and the temperature sensor 27 at this time are read as the outside air humidity mo and the outside air temperature To, and the absolute humidity Mo of the outside air is obtained using the psychrometric chart of the memory. Ask. Next, the blower 11 is rotated forward to enter a drying step. Atmospheric step 31 defines a time interval ΔP (see FIG. 5) for detecting the exhaust state. At each time interval ΔP, the exhaust humidity m detected by the humidity sensor 26 in the input step 32 and the exhaust humidity m detected by the temperature sensor 27 The exhaust gas temperature T is read. The absolute humidity M of the exhaust gas is calculated in the conversion step 33 by referring to the psychrometric chart using these data.

Ma in the state determination step 34 is the absolute humidity of the exhaust gas at the time of the previous measurement, and the initial value is 0. Since M-Ma> 0 in the above-described rising period A, the value of Ma is updated in the updating step 35, and the process returns to before the waiting step 31. In the stationary time B and the decay period C, M−Ma ≦ 0, so the state determination step 34
Then, the process proceeds to the stop determination step 36, where M-Mo is compared with the set value ΔM. When the difference between the exhaust humidity M and the outside air humidity Mo is larger than the set value ΔM, the value of Ma is updated in the update step 37 and the process returns to the state before the standby step 31. When the difference between the exhaust humidity M and the outside humidity Mo becomes equal to or less than the set value ΔM, that is, Ps in FIG.
Alternatively, when the time point of Psh has elapsed, the process proceeds to control step 38, and the apparatus stops.

FIG. 3 is a flowchart of the second embodiment, and FIG. 4 is a hardware configuration diagram thereof. In the second embodiment, a humidity sensor
An absolute humidity sensor is used as 29, and the opening degree of the steam valve 10 is controlled in consideration of the exhaust gas temperature T as drying proceeds.

Referring to FIG. 3, in preparation steps 41 to 43, the blower 11 is reversed to guide the outside air to the exhaust duct 7, the detected humidity (absolute humidity) of the humidity sensor 29 at that time is set to the outside air humidity Mo, and the previous measurement value Ma is used. After that, in the startup step 44, the steam valve 10
Is fully opened to start the device. Then, similarly to the first embodiment, the absolute humidity M and the temperature T of the exhaust gas are read at each time interval ΔP defined in the standby step 31, and the process proceeds to the state determination step. In the rising period, the process returns from the state determination step 34 to the standby step 31 via the update step 35 as in the first embodiment. In the stationary period, M-Ma ≒ 0
From the update step 37 to the steam valve opening degree determination step 45
Proceed to. At the beginning of the transition from the rising period A to the steady period B, the process proceeds to the steam valve control step 46, in which the steam valve 10 is reduced to the steady opening degree. From the next time, the detected temperature T is stored as the steady temperature Tm in the temperature setting step 47. Then, the process returns to the waiting step 31. The stored steady-state temperature Tm is used in step 49 for determining whether or not the steam valve 10 is gradually reduced in the control during the decay period C.

In the decay period C, M-Ma <0, and the update step
The process proceeds to the stop determination step 36 via 48. In this step M
If −Mo ≦ ΔM, control step 38 is performed as in the first embodiment.
Stop the device with. In the case of M-Mo> ΔM, when the exhaust temperature T is higher than the steady temperature Tm in the temperature rise determination step 49, the steam valve 10 is throttled so that the exhaust gas temperature does not rise excessively (FIG. 6). (Refer to the imaginary line.)

In the second embodiment, the opening of the steam valve is controlled by detecting the exhaust gas temperature. However, the control may be performed based on the absolute humidity of the exhaust gas. For example, in the rising period A in FIG. 5, since the absolute humidity read at each time interval ΔP increases gradually, when the increment exceeds a certain set value, the steam valve 10 is kept fully open and the increment is maintained. At a time point a when the value becomes lower than the set value, it is determined that the state has shifted to the steady state B, and the steam valve 10 is reduced to the steady opening degree. Then, the peak value Mmax of the detected absolute humidity is stored, and the detected absolute humidity is set from this peak value, and when the detected absolute humidity decreases by a percentage, b, c,
It is possible to control the steam valve 10 to be successively throttled by d.

By controlling the opening of the steam valve as described above, it is possible to shorten the rising period as much as possible to shorten the drying time, and to prevent an excessive amount of heat from being supplied during the steady period and the falling period, thereby causing energy loss. Can be prevented. In the second embodiment, only the steam valve 10 is controlled. However, in practice, it is preferable to control the speed of the blower 11 simultaneously with the opening of the steam valve 10, and the steam valve is opened. At times, control is performed so that the rotation of the blower is made faster, and when the steam valve is throttled, the rotation of the blower is also made slower.

In the first and second embodiments, the blower 11 is reversed to allow the outside air to pass through the exhaust duct 7 before starting the operation of the drying device. Before the operation, the blower 11 may be turned forward to allow the outside air to pass through the exhaust duct 7 and the absolute humidity sensor 29 may be used to measure the humidity of the outside air.

Such a method has an effect that the object to be dried can be dried stably and with high quality only by the humidity sensor installed in the exhaust duct without installing a humidity sensor on the intake side of the drying device.

On the other hand, a drying device that automates the process of loading and unloading the material to be dried into the device requires a long operating cycle consisting of a process of charging the material to be dried, a drying process, a cooling process, a process of discharging the material to be dried, and a standby process. It repeats automatically over time, but during this repetition it can happen that the ambient environmental conditions, especially the ambient humidity, fluctuate. In such a case, it is necessary to update the stored value of the outside air humidity with time.However, if this update is performed by the humidity sensors 26 and 29 provided in the exhaust duct, the humidity sensor must be updated every operation cycle. It is effective to detect the minimum humidity indicated by 26 and 29 and use this as the updated value of the outside air humidity.

FIG. 8 is a flowchart showing an example of control including an updating procedure according to the above method, and FIG. 7 is an absolute humidity sensor installed in an exhaust duct when the drying apparatus is continuously operated.
29 (see FIG. 4) is a typical time characteristic curve shown.
Here, M is a measurement value of the absolute humidity sensor 29, Mo is a stored value regarded as outside air humidity, and ΔM is a set value indicating a drying end level. Δo is a fixed level value for determining the start of measurement,
When the absolute humidity M measured by the sensor becomes larger than Mo + ΔM + Δo (step 56 in FIG. 8), the measurement of the drying condition is started, and one measurement cycle is set up to a similar time point in the next operation cycle (No. 7). The subscript n in FIG. 7 indicates the operation cycle number.
_(n-1) is the outside air humidity value updated in the previous operation cycle, M
o _(n) indicates the outside air humidity value detected in the current operation cycle. Further, the broken line in FIG. 7 indicates the fluctuation of the ambient humidity.

The characteristic curve for each operation cycle is the same as that shown in FIG. 5. In the initial stage of the drying process, the amount of evaporation increases as the material to be dried is heated and the temperature increases, so that the characteristic curve draws a rising curve. . During the steady drying period, the curve becomes a flat chevron curve, and when the drying proceeds and the amount of evaporation decreases, the characteristic curve becomes a downward curve. Then, there is a time point when the sampling value M of the absolute humidity becomes minimum between the next operation cycle.

In FIG. 8 showing the procedure for updating the stored value Mo regarded as the outside air humidity, when an operation start command is given to the drying device, first, the measurement of the humidity sensor 29 is performed in a state where the blower 11 is operated prior to the start of the automatic operation. The value M is read and set as the initial value of the outside air humidity (steps 51 to 53). Then, after detecting the rising of the operation cycle, the measured value M of the humidity sensor becomes Mo +
When ΔM + Δo is exceeded, the measured value M is stored in the memory as a comparison value Ma (steps 54 to 57), and control according to the method of the present invention is started. Each time the absolute humidity M measured by the humidity sensor 29 becomes smaller than the comparison value Ma, the measurement value M is set as an updated value of the comparison value Ma (steps 58, 59, and 63). The procedure of Steps 60 to 62 is a procedure for terminating the drying process when the measured value M first becomes smaller than the reference value Mo + ΔM indicating the end of drying.
Has been inserted during the update procedure. The end of the drying step is, specifically, the closing of the steam valve 10 and the stop of the rotation of the drum. The above update procedure of Ma is continued even after the drying step is completed, and when the start signal of the next operation cycle is input, the stored value Mo of the outside air humidity is updated with the stored comparison value Ma and the next update is performed. Enter the driving cycle. The comparison value Ma is updated because the minimum value of the absolute humidity in one operation cycle is stored as a result of the operations in steps 59 and 63.
The Mo value is the value of the valley portion of the characteristic curve in FIG. 7, and indicates that the control is performed by regarding the minimum value of the detected humidity in one operation cycle as the outside air humidity in the next operation cycle. Means.

According to the experiment, the characteristic curve of the absolute humidity measured by the humidity sensors 26 and 29 in the exhaust duct is detected at the valley portion when the drying process has been completed and the dried product has been lowered during the loading and unloading process. The set minimum humidity reflects the outside air humidity at that time, and does not become lower than or equal to the absolute humidity of the outside air. Therefore, the absolute humidity sensor installed in the exhaust duct updates the stored value of the outdoor air humidity with the minimum humidity indicated for each operation cycle, so that the external air humidity gradually changes over time as shown by the broken line in FIG. In such a case, the value Mo of the outside air humidity serving as a criterion for judging the end of drying can be updated in response to the change, and a long-time automatic operation can be performed without any trouble.

In the method shown in FIG. 8, the stored value is updated with the minimum humidity value in one operation cycle as the outside air humidity. However, as another method, the humidity sensor 26 when the object to be dried is loaded into or out of the rotating drum 1 or It is also possible to update the 29 detected values as outside air humidity. In the actual operation of the drying device, the blower 11 is turned to suck the outside air when the material to be dried is loaded from the carry-in conveyor with the loading door opened so that the material to be dried is smoothly loaded. However, the humidity sensors 26 and 29 of the exhaust duct
It is sufficiently possible to measure the humidity at this time, and it is practically sufficient to use the measured value at this time as the outside air humidity. As still another method, there is a step of cooling the heated object to be dried by passing outside air through the rotating drum 1 after the drying step is completed. At this time, the object to be dried in the rotating drum 1 is sufficiently dried. It has been confirmed by experiments that there is no practical problem even if the humidity detected by the sensors 26 and 29 in the exhaust duct at this time is the outside air humidity because there is no evaporation of water.

The method of setting the minimum humidity for each operation cycle as the update value of the outside air humidity described above is particularly effective in the case of continuous automatic operation.However, in a device in which the operator instructs the start of the drying process for each operation cycle, for example, In addition to the method shown in FIG. 3 for measuring the outside air humidity before starting the drying step, it is possible to update the outside air humidity value by performing the operation of taking in the measured value at other appropriate timing. .

<< Effect of the Invention >> According to the control method of the present invention described above, it is possible to dry a textile product to an appropriate drying state as set without overdrying the fiber product. Since the operation stop command is given, the drying state does not change due to the outside air condition, and the drying operation can be performed in the shortest time without wasting energy.

In addition, it is possible to measure both the outside air humidity, which is a reference for determination of the dry state, and the exhaust humidity that changes every moment with one humidity sensor, and even when the outside air humidity changes over time,
There is an effect that stable and accurate determination of the dry state can be performed with one humidity sensor.

[Brief description of the drawings]

FIG. 1 is a flowchart of a first embodiment of the method of the present invention,
FIG. 2 is a hardware configuration diagram, FIG. 3 is a flowchart of the second embodiment, FIG. 4 is a hardware configuration diagram, FIG. 5 is a graph showing the relationship between elapsed time and the absolute humidity of exhaust, FIG. FIG. 7 is a graph showing the relationship between elapsed time and exhaust temperature, FIG. 7 is a diagram showing the measured values of the humidity sensor of FIG. 4 over time in a drying apparatus that automatically repeats an operation cycle, and FIG. 9 is a flowchart illustrating an example of control including a procedure for updating a stored value of the control. In the figure, 1: rotating drum, 6: intake duct 7: exhaust duct, 8: heat exchanger 10: steam valve, 11: blower 13: clothing, 20: control device 26, 26o: relative humidity sensor, 27, 27o: Temperature sensor 29: Absolute humidity sensor, M: Absolute humidity of exhaust air Mo: Absolute humidity of outside air, Ma: Previous measured value

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinji Wakaeya 1-1, Tanabe Shrine, Kawasaki-ku, Kawasaki City, Kanagawa Prefecture Inside Fuji Electric Co., Ltd. (56) References JP-A-61-119299 (JP, A) 61-58696 (JP, A)

Claims (4)

(57) [Claims] 1. A container (1) for containing a textile (13),
An intake duct (6) and an exhaust duct (7) connected to the container, humidity sensors (26, 29) attached to the exhaust duct (7), and a blower (11) for passing outside air through the container (1). A method for controlling the operation of a textile product drying apparatus provided with an intake air heating device (8), wherein outside air is passed through an exhaust duct (7) before the drying step of the drying device, and the sensor (26, 29) Absolute humidity detected (M
o), and the deviation between the absolute humidity (M) of the exhaust air detected by the sensors (26, 29) and the stored absolute humidity (Mo) during the operation of the drying device is equal to or less than a preset value. An operation control method for a textile product drying apparatus, wherein the drying apparatus is stopped when the operation is completed. 2. A container (1) containing a textile product (13);
An intake duct (6) and an exhaust duct (7) connected to the container, humidity sensors (26, 29) attached to the exhaust duct (7), and a blower (11) for passing outside air through the container (1). And a heating device for intake air (8), wherein the operation of loading and unloading the device to be dried and the process of drying the product are repeated, and the operation is controlled by the sensor (26, 29). The absolute value of the absolute humidity during one operation cycle is stored as the absolute humidity of the outside air (Mo), and this stored value is updated as needed, and the absolute humidity of the exhaust air detected by the sensors (26, 29) during the drying process. An operation control method for a textile product drying apparatus, wherein the drying apparatus is stopped when a deviation between (M) and the stored absolute humidity (Mo) becomes equal to or less than a preset value. 3. An apparatus according to claim 1, wherein the absolute humidity (M) of the discharged air during operation of the apparatus is detected over time, and the amount of heat of the heating device (8) is controlled by a differential signal or difference signal. Or the operation control method of the textile product drying apparatus according to 2. 4. An apparatus for detecting the absolute humidity (M) of discharged air over time during operation of the apparatus, and controlling the amount of heat of the heating device (8) and the amount of air blown by the blower (11) based on a differential signal or a difference signal thereof. The operation control method for a textile product drying apparatus according to claim 1 or 2, wherein: