JPH02295597A - Drying machine - Google Patents

Abstract

PURPOSE:To reduce noise to be generated during drying operation by detecting dryness of air with much humidity to be exhausted from a drying chamber when an object to be dried is dried and variably controlling the rotation of the drying chamber. CONSTITUTION:A drying machine B is equipped with a motor 3', which rotates and drives a double-wing fan 14 separately from a drum 1, and a detecting means 19 is provided to detect the dryness of the air with the much humidity to be exhausted from an air flow-out port 7 of the drum 1 when an object 9 to be dried is dried. Then, a control means 20 is provided to control the rotating speed of the drum 1 in correspondence to the drying degree of the air with the much humidity. The detecting means 19 is connected to a control circuit 18 and in the control means 20, an inverter circuit 16 is provided to change the rotating speed of a motor 3, which rotates and drives the drum 1, and connected to the control circuit 18. In correspondence to the humidity of the air with the much humidity from the air flow-out port 7 to be detected by the detecting means 19, the control circuit 18 controls a frequency to be generated by the inverter circuit 16.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to, for example, a drum-type dryer for drying objects to be dried such as clothes, and is particularly useful for reducing noise during drying operation. .

[Prior art]

Figure 4 shows an example of the structure of a conventional dryer of this type. In the conventional dryer A described above, as shown in the figure, a drum 1 (drying chamber) containing articles 9 to be dried such as clothes is supported rotatably around a horizontal axis by a bearing 2.2. The drum 1
is connected to a pulley 4 which is rotationally driven by a motor 3 via a belt 5. An air inlet 6 and an air outlet 7 are provided on both sides of the drum 1, and the air inlet 6 and the air outlet 7 are connected by a circulation duct 1O equipped with a drain hole 15. There is. A heater 8 is provided near the air inlet 6, and a humidity sensor 17 is provided near the air outlet 7. A double-winged fan l4 for heat exchange and air circulation is provided at a position facing the air outlet 7.
is rotatably arranged coaxially with the drum 1.
A pulley 12 is attached to the double-blade fan 14, and the pulley 12 is connected via a belt 13 to a pulley 11 which is rotationally driven by the motor 3. In the conventional dryer A having the above configuration, the material to be dried 9
When the drum l containing the drum l and the double-blade fan 14 are rotationally driven by the motor 3, and the heater 8 is heated, heated air flows into the drum 1 through the air inlet 6. Then, the heated air evaporates moisture from the material to be dried 9 to become humid air, and then flows out of the drum 1 through the air outlet 7. The humid air flowing out from the air outlet 7 is transferred to the double-winged fan l.
Heat is exchanged with the outside air on the surface of 4, and moisture is condensed. The moisture is discharged to the outside of the machine through the drain hole 15, and the air from which moisture has been removed is conveyed to the vicinity of the heater 8 through the TL ring duct 10. Then, the air is heated by the heater 8 and flows into the drum l again. In parallel with the above-described air circulation operation, the material to be dried 9 is lifted upward along the side wall inside the drum 1 as the drum 1 rotates, and falls due to its own weight. The action of changing the position of the dried material 9 by moving the dried material 9 up and down within the drum 1 as the drum 1 rotates as described above is called tumbling. Then, by the tumbling, moisture is evaporated from the object 9 to be dried while it is in contact with the heated air, and the entire object 9 to be dried is evenly dried.

The drum 1 is continuously driven to rotate at a rotational speed F until the material 9 to be dried is dried. The determination as to whether the object 9 to be dried has been dried is made based on the value of the air humidity H0 near the air outlet 7 detected by the humidity sensor 17. The air humidity H0 changes over time as shown in FIG. 5, and decreases as the drying process approaches completion.
Therefore, when the air humidity H0 reaches a predetermined value, it is assumed that drying has ended, and the operation of the dryer A is stopped. [Problems to be Solved by the Invention] By the way, in the conventional dryer A, as described above, the drum 1 is continuously driven to rotate at a constant rotation speed F from the start of the drying operation to the end of the operation. Therefore, the sliding noise caused by the rotation of the drum 1 and the tumbling noise of the dried material 9 are constantly generated. This is a major cause of noise generated from the equipment during drying operation. SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a dry bomber having a function of controlling the rotation speed of a drying chamber according to the degree of drying of the material to be dried and reducing noise generated during drying operation. That's true. [Means for Solving the Problems] In order to achieve the above object, the main means employed by the present invention is to circulate heated air through a drying chamber containing the material to be dried, and to In a dryer that rotates a chamber to dry the object to be dried, a detection means detects a degree of dryness of humid air discharged from the drying chamber as the object to be dried is dried; and control means for variably controlling the rotation speed of the drying chamber according to the degree of dryness of the humid air. In the dryer having the above configuration, the detection means for detecting the degree of dry explosion of the humid air discharged from the drying chamber may include, for example, a humidity sensor that directly detects the humidity of the humid air;
A temperature sensor or the like can be used to indirectly detect the humidity of the humid air from the temperature difference between the drying chamber outlet and the upstream side of the heater that heats the air in the air transport direction. [Function] While the humidity of the humid air discharged from the drying chamber is high, the moisture contained in the material to be dried is being evaporated sequentially by the heated air, so the drying chamber is deliberately rotated continuously. There is no need to tumble the material to be dried. Therefore, either rotate the drying chamber at low speed or stop it. As the part of the material to be dried that is directly exposed to the heated air is dried in the drying chamber, when the humidity of the humid air discharged from the drying chamber becomes low, the drying chamber is rotated. , tumble the above-mentioned material to be dried. As a result, the heated air comes into direct contact with the moist portion of the object to be dried, and the evaporation of moisture is activated. By repeating such control operations, the drying chamber can be stopped or rotated at low speed, and the drying chamber can be made quieter during drying operation. [Examples] Examples embodying the present invention will be described below with reference to the accompanying drawings to provide an understanding of the present invention. The following example is an example embodying the present invention, and is not intended to limit the technical scope of the present invention. Here, FIG. 1 is a schematic block diagram of a dryer according to an embodiment of the present invention, FIG. 2 is a time chart of control elements of the dryer, and FIG. 4 is a time chart of control elements of a dryer according to an embodiment of the present invention. Also, elements common to those of the conventional dryer 8 shown in FIG. 4 will be described using the same reference numerals.This embodiment As shown in FIG. 1, dryer B according to A detection means 19 includes a motor 3' for rotational driving and detects the degree of dryness of humid air discharged from the air outlet 7 of the drum 1 as the object to be dried 9 is dried; and the detection means l9.
and a control means 20 for variably controlling the rotational speed of the drum 1 according to the degree of dryness of the humid air detected by. The detection means 19 is arranged near the air outlet 7, similar to the humidity sensor 17 (FIG. 4) of the conventional dryer A, and directly detects the humidity of the humid air discharged from the air outlet 7. A humidity sensor that can detect humidity in real time is used. The detection hand vlt19 is connected to a control circuit 18, which will be described later. The control means 20 has an inverter circuit 16 that changes the rotational speed of the motor 3 that rotationally drives the drum 1, and the inverter circuit 16 is connected to a control circuit 18. The control circuit 18 controls the frequency generated by the inverter circuit 16 in accordance with the humidity of the humid air from the air outlet 7 detected by the detection means 19. Memory (not shown) constituting the control circuit 18
A series of operation programs are stored in advance in the drive unit 100, which allows the inverter circuit 16 to output a predetermined frequency to the motor 3 in accordance with the value of the humidity H0 of the humid air detected by the detection means 19. ing. Next, based on FIGS. 1 and 2, an example of the operation procedure when drying the object 9 to be dried using the dryer B having the above configuration will be described. First, the heater 8 is turned on, and the drum l containing the material to be dried 9 and the double-winged fan l4 are rotated by the motors 3 and 3', respectively. In this case, the double-blade fan 14 is continuously operated at a predetermined rotation speed from the start of drying to the end of drying. Further, the rotational speed F of the drum 1 is set at a predetermined value set in advance in the operation program in accordance with the weight of the material to be dried 9 measured by a weight sensor (not shown) provided on the drum 1. The optimal rotation speed value is selected. In this case, the reason why the drum 1 is first rotated as described above is to tumble the material to be dried 9 housed in the drum 1, so that the water contained in the material to be dried 9 can be reliably evaporated. This is for the purpose of Therefore, by adopting a structure in which the heated air from the air inlet 6 directly hits the material to be dried 9 in the drum 1 and reliably evaporates the moisture contained in the material to be dried 9, It is not necessarily necessary to rotate the drum 1 first. When the moisture contained in the material to be dried 9 begins to evaporate as described above, the value of the humidity H0 of the humid air detected by the detection means 19 gradually increases. And the above humidity H
When the value of 0 becomes equal to the value of H, which is set in advance by the control circuit l8, after the elapse of time T0, the control circuit 1
8 outputs a stop command signal to the drum 1 to the inverter circuit 16, and the rotation of the drum 1 is stopped. Thereafter, the value of the humidity H0 increases slightly, and then remains at a substantially constant value for a while. Then, after time T, elapses,
The value of the humidity H0 begins to decrease, and after the elapse of time T2, the value of the humidity H0 becomes H2, which has been set in advance by the control circuit 18.
is equal to the value of . At this time, a rotation command signal for the drum 1 is outputted from the control circuit 18 to the inverter circuit 16, and the drum 1 starts rotating again. This is because while the humidity H0 of the humid air discharged from the drum 1 is high, the moisture contained in the material to be dried 9 is being evaporated by the heated air. There is no need to tumble the material 9 to be dried by continuous rotation. Therefore, the drum 1 is stopped. When the humidity H0 of the humid air discharged from the drum 1 becomes low as the portion of the object 9 to be dried that is directly exposed to the heated air in the drum 1 is dried, the above-mentioned The drum 1 is rotated again, and the above-mentioned material to be dried 9 is
Perform tumbling. As a result, the heated air comes into direct contact with the moist portion of the object 9 to be dried, and moisture generation is activated.

As described above, as the drum 1 rotates, the humidity H0
The value begins to rise again and becomes equal to the value of Hl again after time T3 has elapsed. Then, the control circuit 18 outputs a stop command signal for the drum 1 to the inverter circuit 16, and the rotation of the drum 1 is stopped. As described above, the ON/OFF control of the drum 1 is repeated an appropriate number of times depending on the weight and type of the material 9 to be dried. Then, after time T4 has elapsed, the value of humidity H0 becomes H2.
Even if the drum 1 is driven to rotate again at the rotational speed F, the humidity H0 does not increase but continues to decrease because the object 9 to be dried is evenly dried. becomes. And time T! After I has passed, when the value of humidity H0 reaches the value of H3 preset by the control circuit 18, it is determined that the object 9 to be dried has been completely dried, and the operation of the dryer B is stopped. ．． In this case, the above set value H I + H2 . H3 is H,>H2>}{
There are three relationships. Further, in the above embodiment, the drum 1 may be controlled to rotate at a low speed without stopping. Therefore, in the dryer B according to this embodiment, the rotation speed of the drum 1 is variably controlled depending on the degree of dryness of the material to be dried 9, so that the drum 1 can be continuously rotated at a relatively high rotation speed. No.
As a result, the sliding noise and tumbling noise of the drum 1 generated during drying operation can be reduced. Further, in the dryer according to the present invention, the humidity of the humid air is indirectly detected from the temperature difference between the outlet of the drum 1 and the upstream side of the heater 8 in the air conveyance direction, and the rotation speed of the drum 1 is controlled. It is also possible to configure In this case, as shown in FIG.
Instead of the detecting means 19), a detecting hand &19' is installed on the upstream side of the air transport direction of the heater 8. Temperature sensors 2 1- and 2 lb are installed near the air outlet 7, respectively. Then, in No. 31jlJ+al, an example of a control procedure when drying the object 9 to be dried using the dryer according to the above configuration is shown. In this case, the temperature of the air before being heated by the heater 8 is determined by the temperature sensor 21. The temperature of the humid air discharged from the air outlet 7 is detected by the temperature sensor 21. The difference in temperature detected by the temperature sensors 211 and 21 is ΔT (T2, I, -'
r2, , ). First, the heater 8 is turned on, and the double-blade fan 14 is continuously controlled to rotate at a predetermined rotation speed set in advance by the motor 3'. Then, the air flowing into the drum l from the air inlet 6 begins to be heated by the heater 8, and the value of the temperature difference ΔT gradually increases. Then, the heated air flowing in from the air inlet 6 starts to evaporate the moisture contained in the object to be dried 9, and when the moisture is evaporated almost uniformly from the surface of the object to be dried 9, The value of the above temperature difference ΔT remains at a substantially constant value for a while. Then, after the time T0 has elapsed, the temperature difference 8T starts to rise again, and after the elapse of the time T1, the temperature difference ΔT becomes equal to the value ΔT set in advance by the control circuit 18. As mentioned above, the value of the temperature difference ΔT is the time T. The reason why the temperature starts to rise again after the elapse of time is because the temperature of the air detected by the temperature sensor 21 rises as the drying effect on the parts directly in contact with the heated air progresses. Then, when the value of the temperature difference ΔT becomes equal to the value of ΔTt predetermined in one day by the control circuit after the time TI has elapsed, the control circuit 1B commands the inverter circuit 16 to rotate the drum 1. A signal is output. Then, the drum 1 begins to be rotated by the motor 3 at a rotational speed F, and the material to be dried 9 is tumbled within the drum 1. When the drum 1 is driven to rotate as described above, the temperature difference ΔT begins to decrease as the drum 1 rotates. This is because when the object to be dried 9 is tumbled, the heated air can come into direct contact with the moist portion of the object to be dried 9, and the evaporation of moisture is activated, which is detected by the temperature sensor 21. This is because the temperature of the humid air begins to drop.

As described above, as the drum 1 rotates, the temperature difference ΔT
begins to decrease, and after the elapse of time T2, when the value of ΔT becomes equal to the preset value of ΔT2, the control circuit 18 again sends the drum 1 signal to the inverter circuit l6.
A stop command signal is output. Then, the rotation of the drum 1 is stopped, and in this state, the drying effect on the portion of the object 9 to be dried that is directly hit by the heated air proceeds.

The ON/OFF control of the drum 1 as described above is applied to the drying material 9.
The process is repeated an appropriate number of times depending on the weight and type of material. and,
As the drum 1 rotates, the temperature difference ΔT continues to increase without decreasing, and after time T1 has elapsed, the temperature difference ΔT reaches the preset value.
When the value of T becomes equal to the value of T, the operation of the dryer is stopped. Even if the drum] is rotated as shown above, the temperature difference ΔT
The reason why the temperature continues to rise without decreasing is because the material to be dried 9 is dried evenly and the temperature of the air detected by the temperature sensor 2lb increases. In this case, the above set value ΔT,
．． ΔT2+ ΔT has the relationship Δ71>Δ7,>ΔT2. Furthermore, based on the following conditions, the drum 1 may be controlled to turn on and off according to the procedure shown in Figure 3. That is, the difference between the temperatures T21a and T2+b detected by the temperature sensors 211 and 2lb at time t is expressed as ΔT(t
), then ΔT(t)<ΔTk. The rotation of the drum 1 is stopped under the following conditions: ΔT2≦ΔT(L)≦ΔT, ΔT(t) <ΔT(t−ΔL) (the value of ΔT tends to decrease), and ΔT(t)≧ΔT]. Local area, ΔT2≦ΔT(t)≦ΔT+ and ΔT(t)≧Δ
T(t-Δ1) (8T value tends to increase), ΔT<ΔT
(t) Under each condition <ΔT3, drum 1 is rotated. Therefore, in the dryer described above, as in the case of the dryer B, the rotational speed of the drum l is variably controlled depending on the degree of drying of the material to be dried 9, so that the drum l is rotated at a relatively high rotational speed. It is not rotated continuously. As a result, the noise generated during drying operation is reduced. In each of the above embodiments, a so-called dehumidifying type dryer that dehumidifies and circulates humid air with respect to the drum 1 was explained as an example. It can also be used in so-called exhaust type dryers that exhaust air outside the machine without circulating it. [Effects of the Invention] As described above, the present invention provides a dryer that dries the object to be dried by circulating heated air through the drying chamber containing the object to be dried and rotating the drying chamber. a detection means for detecting the degree of dryness of the humid air discharged from the drying chamber as the object is dried; and variably controlling the rotation speed of the drying chamber according to the degree of dryness of the humid air detected by the detection means. Since the dryer is characterized in that it is equipped with a control means, it is possible to variably control the rotation speed of the drying chamber depending on the degree of dryness of the material to be dried, thereby reducing the noise generated during drying operation. can.

[Brief explanation of the drawing]

FIG. 1 is a schematic block diagram of a dryer according to an embodiment of the present invention, FIG. 2 is a time chart of control elements of the dryer, and FIG. FIG. 4 is a schematic block diagram of a conventional dryer, and FIG. 5 is a time chart showing the relationship between humidity and drum rotation speed of the conventional dryer. [Explanation of symbols] 1...Drum (drying room) 3...Motor 6...
- Air inlet 7... Air outlet 8... Heater 9... Material to be dried 16... Inverter circuit 18... Control circuit 19.19'... Detection means 20... Control means 21m. 2lb...Temperature sensor B...Dryer.

Claims (1)

[Claims] 1. In a dryer that circulates heated air through a drying chamber containing an object to be dried and rotates the drying chamber to dry the object to be dried, air is discharged from the drying chamber as the object to be dried is dried. and a control means for variably controlling the rotation speed of the drying chamber in accordance with the degree of dryness of the humid air detected by the detection means. dryer.