JPH0796993B2 - Wood drying equipment - Google Patents

Description

TECHNICAL FIELD The present invention relates to a wood drying apparatus, and more particularly to a wood drying apparatus including a dehumidifier having a refrigeration cycle.

[Conventional technology]

Conventionally, this type of device is constructed as shown in FIG. In the figure, (1) is a drying cabinet, (2) is an internal compressor (2a), blower (2b), cooler (2c), reheater (2
d) Dehumidifier that constitutes a normal refrigeration cycle by
(3) is the air inlet (2g) of the dehumidifier (2) and the drying chamber (1)
(4) is a ventilation duct that communicates the air outlet (2h) of the dehumidifier (2) with the drying cabinet (1), (5) is a stirring fan for air inside the drying cabinet (1), and (6) ) Is a heating and humidifying device, for example, a steam spraying device, which has a solenoid valve (6a) in the steam supply pipe. (7) is the wood piled up in the dry store (1). (2e) and (2f) are a dehumidifier (2), a drain pan and a drain port for receiving condensed water, and (2i)
Is a control box containing a control device for controlling the operation of the dehumidifier (2).

Next, the operation will be described. The dehumidifier (2) has a built-in blower (2b) for sucking the air in the drying chamber (1) through the suction duct (3) and the air suction port (2g), and then the cooler (2c) and the reheater. It is returned to the drying chamber (1) through the blower duct (4) from the blower port (2h) via (2d). When this circulating air passes through the cooler (2c), dew condensation occurs because the surface temperature of the cooler (2c) is lower than the dew point temperature of the circulating air, and the condensed water is collected by the drain pan (2e) and the drain port (2f ) It is designed to drain more. Circulating air is cooled by the cooler (2
c) After the absolute humidity and temperature have decreased due to passage, the temperature is raised by heating with a reheater. The reheat amount is generally larger than the cooling amount by the amount equivalent to the power heat amount of the compressor (2a), and since there is no latent heat change, the circulating air temperature after passing through the reheater (2d) is The temperature is higher than the internal air temperature, so that the relative temperature decreases in combination with the absolute temperature decrease. Thus, the air having a low relative temperature returns to the drying chamber (1) through the blower duct (4). The air in the drying chamber (1) is stirred by a stirring fan (5) to make the temperature and humidity uniform. In this way, by operating the dehumidifier (2), the relative humidity in the drying chamber (1) gradually decreases, and moisture evaporation of wood is promoted to dry it. The water vaporized from the wood is condensed in the cooler (2c) of the dehumidifier (2) and is discharged from the drain port (2f).

On the other hand, in the drying of wood, first, moisture evaporates from the surface and a difference in water content between the surface portion and the inside occurs, so that the internal moisture gradually moves to the surface portion and the drying progresses. In this process, internal stress is generated due to shrinkage of the tissue in the drying process. For example, when the dehumidification speed of the air in the drying chamber (1) is fast, or when the initial moisture content of the target wood is not uniform inside the wood. Cracks may form on the surface and inside the wood during the drying process. In order to prevent such cracks, if the humidity inside the drying chamber (1) drops rapidly during the pre-drying process and during drying, open the solenoid valve (6a) and spray steam to heat and humidify the device. (6) is operated to humidify the air in the drying chamber (1) so that the surface of the wood and the inside of the wood that are drying quickly absorb water, thereby achieving a uniform drying speed of the wood structure.

In addition, depending on the type of wood, in order to kill harmful insects in the wood, the heating and humidifying device (6) is operated (high temperature steam spray),
The wood may be heated to a high temperature through the air in the drying cabinet (1).

[Problems to be Solved by the Invention]

Since the conventional wood drying device is configured as described above, the operation of the heating or humidifying device exposes the dehumidifier to a high-temperature or high-humidity atmosphere, which deteriorates the insulation of electrical components inside the dehumidifier and metal parts. However, there is a problem that the life of the dehumidifier becomes short due to corrosion of the dehumidifier.

The present invention has been made to solve the above problems, and an object of the present invention is to obtain a wood drying apparatus which is less likely to cause component failures and which can be economically operated.

[Means for Solving the Problems]

The wood drying apparatus according to the present invention is a ventilation fan for ventilating the inside of a drying cabinet with the outside air, a shutter for opening and closing an inside air circulation path,
A detector that detects when the temperature or humidity inside the drying chamber has exceeded a prescribed value, and in response to the detection of a temperature or humidity that is greater than or equal to the prescribed value by this detector, the operation of the dehumidifier is stopped and the shutter is closed. A controller for operating the ventilation fan is provided in response to detection of temperature or humidity higher than a predetermined value by the detector and stop of the heating / humidifying device.

[Action]

In the wood drying device according to the present invention, when the temperature or humidity inside the drying chamber exceeds a predetermined value due to the operation of the heating / humidifying device, the operation of the dehumidifier is stopped and the air circulation path from the dehumidifier to the inside of the drying chamber is closed. After the operation of the heating / humidifying device is finished, the ventilation fan operates to introduce outside air and the temperature or humidity inside the drying chamber decreases to a predetermined value that does not affect the life of the dehumidifier, and then the air circulation path is opened to The operation is restarted.

〔Example〕

FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, (1) to (7) are the same as the conventional example shown in FIG. (3a) is an air passage shutter provided in the suction duct (3), (3b) is an air passage shutter (3a)
Drive motor, (4a) is a power type air duct shutter provided in the air duct (4), (8) and (9) are both outside air inlets and exhaust ports provided in the drying chamber (1), and (8a ) Is a ventilation fan for introducing outside air provided in the outside air inlet (8), (8b)
Is an outside air shutter opened by the wind pressure of the outside air ventilation fan (8a), (9a) is an exhaust ventilation fan provided at the exhaust port (9), and (9b) is an exhaust shutter opened by the wind pressure of the exhaust ventilation fan (9a). , (10) and (11) are temperature detectors and humidity detectors respectively provided in the drying chamber (1), and (12) is a controller.

The electric circuit of the controller (12) is shown in FIG. (16) is the operation switch of the heating / humidifying device (6a), and (13) is the switch (1
A first electromagnetic contactor connected to the power supply via (6), (10
(a) is a temperature contact point (11a) that receives a signal from the temperature detector (10) and closes terminals (110a) and (210a) below a predetermined temperature, and closes terminals (110a) and (310a) above a predetermined temperature. ) Receives the signal from the humidity detector (11) and the terminal (11
1a) and terminal (211a) are closed, and terminal (11a)
1a) and (311a) are closed humidity contacts, (14) is the temperature contact (10a) terminal (110a)-(210a), humidity contact (11a) terminals (111a)-(211a) through the power supply in order The second electromagnetic contactor connected to the (15) is the terminal (1) of the temperature contact (10a).
10a)-(310a) and humidity contact (11a) terminal (111a)-
(311a) and normally closed contact (13a) of the first electromagnetic contactor (13)
A third electromagnetic contactor connected to the power supply through
(2), (3b), (5), (8a), (6a) and (9a) are the same as in FIG. The outside air introduction ventilation fan (8a) and the exhaust ventilation fan (9a) are connected to the power source through the normally open contact (15a) of the third electromagnetic contactor (15), and the dehumidifier (2) is connected to the second The electromagnetic contactor (14) is connected to a power source through a normally open contact (14a). The drive motor (3b) of the air duct shutter (3a) is connected to the power supply, and the drive input terminal thereof is connected to the normally open contact (14b) of the second electromagnetic contactor (14). The electromagnetic valve (6a) of the heating / humidifying device (6) is connected to the power source through the normally open contact (13b) of the first electromagnetic contactor (13). The stirring fan (5) is directly connected to the power supply.

Next, the operation will be described. The stirring fan (5) is constantly operated to stir the air in the drying chamber (1) to make the temperature and humidity of each part uniform.

First, when proceeding with the drying of wood, switch (1
When 6) is cut off, the first electromagnetic contactor (13) is de-energized, the normally open contact (13b) is opened, and the heating and humidifying device (6) is opened.
The solenoid valve (6a) is closed, and no steam is sprayed into the drying chamber (1). Therefore, the temperature and humidity inside the drying chamber () are not high, and the temperature contact (10a) and the humidity contact (11a) are
The terminals (110a)-(210a) and (111a)-(211a) are closed, the second electromagnetic contactor (14) is energized, and the third electromagnetic contactor (15) is deenergized. As a result, the normally open contacts (14a), (14b) of the second electromagnetic contactor (14) are closed, and the third electromagnetic contactor (15a) is open. Second electromagnetic contactor (1
By closing the normally open contact (14b) in 4), the suction duct (3)
The drive motor (3b) of the air duct shutter (3a) provided in the above stops at the rotational position where the air duct shutter (3a) is opened. At the same time, the dehumidifier (2) is energized and operates by closing the normally open contact (14a). The dehumidifier (2) has a blower (2
By operating b) and the compressor (2a), the air in the drying cabinet (1) is sucked through the suction duct (3) from the air suction port, dehumidified and dried, and then the air duct (2h) is blown by the air duct (4). Blow to. The gravity type air duct shutter (4a) provided in the air duct (4) is opened by wind pressure and the dry air returns to the drying chamber (1). Ventilation fan (8a) for introducing outside air installed in the drying cabinet (1)
And the exhaust ventilation fan (9a) are connected to the third electromagnetic contactor (1
The operation is stopped by opening the normally open contact (15a) in 5), and the outside air shutter (8b) and the exhaust shutter (9b) are closed. Thus, as in the conventional case, the air in the drying cabinet (1) circulates in the dehumidifier (2) and the air in the drying cabinet (1) dries,
Drying proceeds due to water evaporation of wood.

Next, in order to make the drying speed of the inside of the wood uniform and prevent cracking of the wood, a drying room (1) is used to humidify the air inside the wood so that the wood absorbs moisture, and in order to kill pests inside the wood, the drying room (1 ) When heating the internal air to heat the wood, the switch (16) is thrown in and the first electromagnetic contactor (13) is energized. As a result, the normally closed contact (13a) is opened, the third electromagnetic contactor (15) is deenergized, and the normally open contact (15a) is opened, so that the outside air provided in the drying chamber (1) is introduced. The ventilation fan (8a) and the exhaust ventilation fan (9a) are stopped in operation, and the outside air shutter (8b) and the exhaust shutter (9b) are closed. Further, the normally open contact (13b) is closed and the electromagnetic valve (6a) of the heating / humidifying device (6) is energized to open the valve and spray steam into the drying chamber (1). In the drying chamber (1), the stirring fan (5) stirs the air to make the wood moisture absorption and heating uniform. In this way, the drying speed inside the wood can be made uniform and the pests can be exterminated. When steam spraying is started and the temperature and humidity inside the drying cabinet (1) rises, and the temperature detector (10) or humidity detector (11) detects a temperature or humidity above a predetermined value,
The temperature contact (10a) or humidity contact (11a) is connected to each terminal (21
0a) or the terminal (211a), and the second electromagnetic contactor (14) is deenergized. This allows its normally open contact (14a)
Is opened, the dehumidifier (2) stops operating, and the gravity type air duct shutter (4a) provided in the air duct (4) is closed by the gravity because it does not receive wind pressure. Also,
By opening the normally open contact (14b), the drive motor (3b) of the air duct shutter (3a) provided in the suction duct (3) stops at the rotational position where the air duct shutter (3a) is closed, and the suction side air duct is closed. Cut off. In this way, the inside air circulation path formed between the inside of the dehumidifier (2) and the drying store (1) is shut off.

Next, immediately after opening the switch (16) again to deactivate the first electromagnetic contactor (13) and closing the electromagnetic valve (6a) of the heating / humidifying device (6), the temperature inside the drying chamber (1) The humidity is high, and the temperature contact (10a) or humidity contact (11a) is closed and connected to the terminal (310a) or the terminal (311a), respectively. At this time, since the normally closed contact (13a) of the first electromagnetic contactor (13) is also closed,
The ventilation fan (8a) for introducing the outside air and the ventilation fan (9a) for the exhaust air, which are provided in the drying chamber (1), are operated, and the outside air shutter (8b)
And the exhaust shutter (9b) is opened by the wind pressure, the outside air is introduced into the drying chamber (1) through the outside air inlet (8), and the high temperature and high humidity air in the drying chamber (1) is discharged through the exhaust port (9). To be done. The outside air introduction ventilation fan (8a) and the exhaust ventilation fan (9a) both have temperature and humidity in the drying chamber (1) that drop below a predetermined value that does not affect the life of the dehumidifier (2), (10a) and humidity contact (11a) are both terminals (210
a), operate until the terminal (211a) is closed. Also, the temperature and humidity inside the drying cabinet (1) both drop below a specified value, and the temperature contact (10a) and humidity contact (11a) are both operated until they are closed and connected to the terminals (210a) and (211a), respectively. To do. Further, when the temperature and humidity inside the drying cabinet (1) both drop below a predetermined value, and both the temperature contact (10a) and the humidity contact (11a) are closed and connected to the terminal (210a) and the terminal (211a), respectively. The second electromagnetic contactor (14) is energized, its normally-open contact (14a) is closed, the dehumidifier (2) starts operating, and the blower side air passage shutter (4a) opens due to wind pressure, Normally open contact (14b)
Closed and the air duct shutter (3) installed in the suction duct (3)
The drive motor (3b) in a) rotates to open the suction side air passage. In this way, the process returns to the wood drying process.

In the above embodiment, the air duct shutter (4a) of the blower duct (4) is of the gravity type, but another method, for example, using a drive motor, is used simultaneously with the air duct shutter (3a) of the suction duct (3). It may be operated directly by the controller (2). Also,
The heating / humidifying device may be of other type than the steam spraying type, and when it has only one function of heating or humidifying, the humidity detector (11) and its humidity contact (11
a) Alternatively, only one of the temperature detector (10) and its temperature contact (10a) may be provided.

〔The invention's effect〕

As described above, according to the present invention, a drying cabinet for storing wood,
A heating / humidifying device that heats or humidifies the inside of the drying cabinet by operating an operation switch, a dehumidifier having a refrigeration cycle, and air blowing and suction that connects the dehumidifier to the drying cabinet to form an internal air circulation path. In a wood drying device equipped with a duct, a ventilation fan for ventilating the inside of the drying chamber with the outside air, a shutter for opening and closing the inside air circulation path, and detecting that the temperature or humidity inside the drying chamber exceeds a predetermined value According to the detection of the detector, and the temperature or humidity of a predetermined value or more by this detector, while stopping the operation of the dehumidifier and closing the shutter, the detection of the temperature or humidity of a predetermined value or more by the detector and It is characterized in that a controller for operating the ventilation fan according to the stop of the heating / humidifying device is provided.

Therefore, when the temperature or humidity inside the drying chamber exceeds a predetermined value due to the operation of the heating / humidifying device, the operation of the dehumidifier is stopped,
Since the air circulation path from the dehumidifier to the inside of the dryer is closed, the dehumidifier is not exposed to high temperature or high humidity atmosphere, and there is no insulation deterioration of the electrical parts inside the dehumidifier, corrosion of metal parts, etc. The life of the dehumidifier is extended. In addition, after the operation of the heating and humidifying device, the ventilation fan introduces outside air into the drying chamber until the temperature and humidity of the air inside the drying chamber drop below a predetermined value that does not affect the life of the dehumidifier. Since the high-humidity air is discharged to the outside of the drying chamber, the dehumidifying operation can be restarted promptly, and the wood drying efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a wood drying apparatus according to an embodiment of the present invention, FIG. 2 is an electric circuit diagram of the embodiment shown in FIG. 1, and FIG. 3 is a configuration diagram showing a conventional wood drying apparatus. . (1) is a drying chamber, (2) is a dehumidifier, (3) is a suction duct, (4) is a ventilation duct, (6) is a heating or humidifying device, (8) is a ventilation fan, (3a), ( 4a) is an air duct shutter, (10) is a temperature detector, (11) is a humidity detector, and (12).
Is a controller. In the drawings, the same reference numerals indicate the same or corresponding parts.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Denji Tanaka 2-5 Marunouchi, Takamatsu City, Kagawa Prefecture Shikoku Electric Power Co., Inc. Company Wakayama Works (72) Inventor Toshiro Abe 6-5-6 Tehira, Wakayama, Wakayama Sanryo Electric Co., Ltd. Wakayama Works (72) Inventor Seiichiro Ikehara 2-3-3 Marunouchi, Chiyoda-ku, Tokyo Inside Ryo Electric Co., Ltd.

Claims (1)

[Claims] 1. A drying cabinet for storing wood, a heating / humidifying device for heating or humidifying the inside of the drying cabinet by operating an operation switch, a dehumidifier having a refrigeration cycle, and the dehumidifier connected to the drying cabinet. In a wood drying device equipped with a ventilation and suction duct that forms an internal air circulation path, a ventilation fan that ventilates the inside of the drying room with outside air, a shutter that opens and closes the internal air circulation path, and a temperature inside the drying room. Alternatively, a detector for detecting that the humidity has reached a predetermined value or higher, and in response to the detection of a temperature or humidity of a predetermined value or higher by this detector, the operation of the dehumidifier is stopped, the shutter is closed, and the detector is A wood drying apparatus, characterized in that a controller for operating the ventilation fan is provided in response to detection of a temperature or humidity higher than a predetermined value by the above and stop of the heating and humidifying apparatus.