JPH037866B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention rotates by holding the left and right butt end faces of a log, which is a raw material, with a veneer lace, while rotating a long cutter that spans the entire length of the log. This relates to a drying device for drying plate-like materials containing a large amount of moisture, such as wide veneers obtained by cutting a predetermined amount into the outer peripheral surface of logs and turning them.

(Prior art) As a means for drying plate-like objects such as veneers, there is a conveyance method in which the parts other than the inlet and outlet are shielded in the form of a closed container with a heat-retaining plate made of heat insulating material, and the object to be dried is transferred at an appropriate speed within the device. A mechanism is often used to pass and circulate hot air over the entire width of the object to be dried in the transport direction or perpendicularly to the same direction.

For example, Japanese Patent Application No. 54-62384 (Japanese Patent Application No. 56-973)
A vertical flat plate dryer has been proposed. This invention sequentially and continuously dries flat plates of a predetermined size. A fork chain conveyor, in which a large number of rod-shaped forks are arranged in a comb shape, is driven to circulate in two endless vertical lines, and the flat plates are horizontally dried on the forks. This is a dryer in which hot air is continuously blown across the entire width of the flat plate from the tip of the fork, and a duct for blowing hot air is provided at the base end of the fork.

(Problems to be Solved by the Invention) When drying a plate-shaped object to be dried by simply continuously rubbing hot air along the plate surface orthogonal to the thickness direction as in the above-mentioned conventional method, the plate This results in uneven drying over the entire area of the object.

For example, when drying a plate-shaped object 31 by continuously blowing a group of hot air indicated by the arrow L from the right to the left in the figure as shown in FIG. 4, the plate-shaped object 31 is divided into three parts each vertically and horizontally. When examining the degree of dryness for each of the nine sections, the top order is T, Z, W, S, X, Y, R,
The order is V, U, and then from the upper layer (R, S, T) to the lower layer (X, Y,
It can be seen that the middle layers (U, V, W) are dried in this order. In addition, the upper tiers (R, S, T) are easier to dry than the lower tiers (X, Y, Z), and furthermore, with respect to the plate-shaped object 31, the hot air inlet side (T) is more dry than the hot air exit side (R, U, X). , W, Z) show a tendency to dry much more easily.

From the above phenomena, for example, if the middle layer is dried to a predetermined finished moisture content, the upper and lower layers will be overdried, resulting in waste, and if the upper and lower layers are finished to the appropriate moisture content, the middle layer will be Problems arose, such as insufficient drying and the need to re-dry the entire plate.

(Means for Solving the Problems) The drying device for plate-like objects of the present invention includes a main body of the drying device including an inlet and an outlet for the plate-like objects, and a drying device for drying the plate-like objects to be dried at right angles to the traveling direction. an endless conveyance belt in which a large number of rod-shaped forks, which are held in an upright position, are erected on a conveyance surface and driven in circulation between an inlet and an outlet of the drying device main body; A hot air blowing duct and a hot air exhaust duct each having a plurality of air blowing ports or exhaust ports arranged close to each other on both sides and partitioned in a height direction with respect to the conveying surface of the endless conveying belt, and the hot air blowing duct and the hot air exhaust duct. The damper is installed at each air outlet and each exhaust outlet of the exhaust duct and whose opening degree can be adjusted independently.

(Function) To explain the case where the configuration of the present invention is applied to the plate-like object shown in FIG. Air is blown from the air outlet divided into the middle and lower layers, and hot air passes through T, S, and R in sequence from the top, hot air blows through W, V, and U, and hot air passes through Z, Y, and X in sequence from the top. It is diverted to hot air. An air volume adjustment mechanism is installed to control the amount of hot air in each layer, and the amount of hot air is adjusted accordingly.For example, in response to the unbalanced drying of each layer as described above, the amount of air in the upper and lower layers, which are easier to dry, is reduced. By increasing the air volume in the middle layer, it is possible to equalize the dryness of the entire plate-like object.

In addition, by arranging the ventilation duct and the exhaust duct on both sides of the plate-like object in close proximity to the plate-like object, the hot air can pass between the plate-like objects without resistance, and can be applied to the entire surface of the plate-like object. Hot air of the same temperature can be brought into contact throughout the area.

Therefore, the uniformity of the dried state of the plate-like material is extremely high.

(Embodiment) FIGS. 1 to 3 schematically represent an embodiment of the present invention, and FIG. 3 is an overall side view.

In these figures, a drying device 1 is constructed by a first zone 2, a second zone 3, a cooling device 4, and conveyors etc. that connect the above-mentioned devices, arranged linearly on the floor (non-linear arrangements are also possible). It is configured. In both the first and second zones, an endless conveyance belt 12 such as a link chain equipped with a large number of rod-like forks 13 that hold the plate-like object in a vertical state perpendicular to the conveyance direction is driven and circulated over the entire length of each zone. , a fan that circulates hot air perpendicular to the thickness direction of the plate-shaped object (orthogonal to the direction of conveyance of the plate-shaped object);
Air ducts, etc. are installed.

FIG. 1 is a cross-sectional view of the drying device, and FIG. 2 is a plan view with the upper heat insulating plate etc. removed. A unit drying device 10 is shown between A and A' in FIG. The first zone, the second zone, etc. shown in FIG. 3 are formed by being connected to the zone.

As shown in FIGS. 1 and 2, the drying device is constructed with a machine frame 11, and in the center of the width of the machine, two endless conveyor belts 12, such as link chains, each having a large number of rod-shaped forks 13 are stretched. and is driven in the direction of arrow C by an electric motor at an appropriate speed. In addition, as shown in Figures 1 to 3, the center space in the upper half of the dryer is used for the forwarding process for transferring plate-shaped materials, and the center space in the lower half suspends rod-shaped forks vertically and returns empty. Furthermore, a hot air heating device 15, a ventilation fan 16, a ventilation passage 20, an air volume adjustment mechanism 23, a ventilation duct 24, etc. are arranged on one side of the left and right space of the upper half, and the other parts of the upper half An exhaust duct 25, an air volume adjustment mechanism 27, an exhaust fan 18, a ventilation passage 20', and the like are appropriately arranged on one side of the exhaust duct 25.

In FIG. 2, reference numeral 15 denotes a hot air heating device, which in this embodiment uses a burner for burning wood flour, gas, kerosene, etc., and is fixedly installed near the right end of the drying device. Reference numeral 16 in the figure is a blower fan that sucks hot air heated by the heating device 15 in the air passage 20 in the direction of arrow K, and directs it toward the right side of the plate-shaped object 31 being transferred by the endless conveyor belt. Air is efficiently blown in the direction of arrow L from the air duct 24 via the air volume adjustment mechanism 23.

In this embodiment, as shown in FIG.
The endless conveyor belt is partitioned into stages, and as shown in FIG. It has a shape that widens towards the end. An air volume adjustment mechanism 23 using a damper or the like is provided at each stage close to the blower fan 16, so that the air volume can be arbitrarily controlled at each stage in the board width direction.

Therefore, the high-temperature hot air passes through the surface of the plate-like object from the right end to the left end in the direction of arrow L' at the optimum air volume for each stage, dries the plate-like object, and becomes low-temperature hot air as shown by arrow M.
It advances from the direction to the N direction and reaches the ventilation passage 20'.

After reaching the ventilation path 20', the hot air heating device 15' fixedly installed near the left end of the drying device turns the air into high-temperature hot air again and is sucked into the blower fan 16'.
The air volume is controlled separately for each upper and lower stage through the air volume adjustment mechanism 23', and the air flows from the air duct 24' in the direction of arrow O, and then from the left end side of the plate-shaped object 31 to the right end side, from arrow O' to P direction. The air blows through, dries the plate-like object, lowers the temperature, and reaches the ventilation passage 20.

The following arrows indicate K-L-L'-M-N-O-O'-P-K
The endless transport belt 12 sequentially dries the plate-shaped materials that repeatedly pass through the circulation path and are transported one after another by the endless transport belt 12. Note that the hot air heating device 15' is placed on the left side with the front and back phase of the drying device being slightly shifted from the heating device 15 placed on the right side. Since there are local differences in the degree of drying of plate-shaped objects, the hot-air heating device The ventilation fan 16' other than 15', the ventilation path 20', the air volume adjustment mechanism 23', the ventilation duct 24', etc. are all symmetrical and are arranged slightly offset in the front-back direction.

If we touch on the drying progress of plate-shaped objects, for example, when drying a veneer, even if the drying conditions are the same throughout the drying process, the drying does not necessarily occur in proportion to the passage of time, and from constant rate drying in the early stage of drying to decreasing rate drying eventually. The reality is that the hot air is dried while shifting, and for this reason, it is ideal to change the direction of the hot air blowing to the plate-shaped object frequently and with a fine texture.

Reference numeral 18 in FIGS. 1 and 2 is an exhaust fan;
25 is an exhaust duct, and 27 is an air volume adjustment mechanism. These are arranged facing each other on the opposite side of the air duct 24, and divide the width direction of the plate-shaped object (height direction from the conveyance surface of the endless conveyance belt) into multiple stages, and divide the hot air sent into multiple stages and rectify it. The air duct 24 is generally divided into multiple stages in the width direction of a plate-shaped object (in the embodiment shown in Fig. 1, there are four stages on the ventilation side and three stages on the exhaust side). composition).

The starting end of the exhaust duct 25 is symmetrical to the blower duct 24, and is wide open in the longitudinal direction of the endless conveyor belt 12 close to the left edge of the plate-like object on the side where the hot air blows through in plan view. is gradually narrowed down in a funnel shape from this starting end to reach the air volume adjustment mechanism 27 in front of the exhaust fan 18. In addition, in the width direction of the plate-shaped object, an air volume adjustment mechanism 27 such as a damper for controlling the air volume of each layer is separately installed in the exhaust duct, and an exhaust fan 18 is installed near the exhaust duct to reduce the temperature. This device sucks hot air in the direction of arrow M.

As mentioned above, by appropriately controlling the air volume for each layer on the exhaust side and suctioning, the first
As shown in the figure, for example, the hot air on the upper stage enters the plate-shaped object 31 from the arrow L1 and passes through L1' to M1, and the middle hot air flows from L2 to M2 through L2'.
In addition, the hot air in the lower layer passes through each layer separately, forming hot air that blows from L3 to M3 via L3' and hot air that blows from L4 to L3' and merges into M3. Turbulent flow of hot air occurs near the boundaries of each layer in the vertical direction. etc., and can be even more effective.

In addition, from the bottom of the ventilation duct 24, arrows L4 and L
4' direction, the hot air blowing up to the lower end near the center of the plate, when drying with hot air while conveying the plate in an upright position perpendicular to the conveyance direction, as explained at the beginning, the lower end of the center of the plate This hot air route was installed in response to the fact that the area showed a tendency to be difficult to dry. Further, on the right end side of the plate-shaped object 31, devices equivalent to the exhaust control devices arranged on the left end side described above are installed symmetrically and slightly shifted in the front and rear direction, including an exhaust fan 18' and an exhaust duct 25. ', an air volume adjustment mechanism 27', and the like are respectively arranged.

The transfer of the material to be dried will be explained using FIG. First, the plate-like material is sent to the entrance of the first zone 2 of the drying device in the direction of arrow A by the carry-in conveyor 6,
Fork 13 rotating in the direction of arrow B from below
It is sandwiched in between and held vertically perpendicular to the transport direction, and while being transported in the direction of arrow C, it is exposed to hot air alternately from the left and right sides perpendicular to the transport direction.
Then, as the fork rotates, it moves in the direction of arrow D at the end of the first zone and is placed on the conveyor of the reversing mechanism 7 waiting there.

A second zone 3 is provided at the end of the conveyor of the reversing mechanism 7.
The starting end of the zone is arranged in a complicated manner, and after the plate-shaped object is scooped up by the fork 13 rotating from below in the direction of arrow E at the starting end in the same manner as the starting end of the first zone, It is held in this position and is transported in the direction of arrow F while receiving hot air alternately from the left and right sides. The difference from the first zone is that the transfer continues in an upright state in which the top and bottom of the plate-like objects are reversed due to the action of the reversing mechanism 7 that bridges the two zones arranged in front and back. As mentioned above, this has the effect of preventing differences in the degree of dryness from appearing in the vertical and horizontal directions when exposed to hot air in an upright position. Note that 5 is an exhaust pipe for appropriately discharging the humid air inside the drying device to the outside of the drying device.

Subsequently, at the end of the second zone, the plate-like material is transferred to the discharge conveyor 8 by fork rotation in the direction of arrow G, and the drying process is completed. Further, the plate-shaped object that has proceeded in the direction of arrow H by the carry-out conveyor 8 is scooped up from its end by the fork of the cooling device 4, placed on the fork in a horizontal state, and then ascended in the direction of arrow I, and then placed in a vertical state. The cooling device moves forward, becomes horizontal again, descends, and is transported out of the cooling device by a delivery conveyor 9 that is connected to the vicinity of the end of the cooling device.

Although not shown, the cooling device 4 has a structure in which a fan or the like sucks in cold air from outside and blows it from the side onto the plate-shaped object, and continuously blows hot air for drying in the first and second zones. This is used to cool plate-like objects that have become hot due to exposure to water to a point where they can be handled by hand.

As described in detail above, the present invention provides hot air blowing passages or hot air exhaust passages after rubbing the surface of a plate-shaped article to a plate-shaped article when hot air is blown perpendicularly to the thickness direction of the plate-shaped article. Since the object is partitioned into multiple stages in the width direction of the board and the air volume can be controlled for each stage, the air volume can be controlled by taking into account in advance the degree of dryness that occurs locally on the board. We were able to eliminate uneven drying. In addition, due to alternating directions of the hot air on the plate-like object, switching the top and bottom of the plate-like object, and creating a laminar flow of hot air by combining the ventilation duct and exhaust duct, the degree of dryness of the plate-like object may be uneven in some areas. This makes it possible to average out the losses caused by re-drying and over-drying that frequently occur in the past when drying plate-like objects.

Although this embodiment mainly describes a means for drying a plate-like object with hot air while conveying it vertically, the present invention can also be fully utilized in a means for holding a plate-like object horizontally. is possible.

Further, although the hot air heating device employs a burner that burns combustible materials, it may be replaced with a heat exchanger using other heat media such as steam or other heat medium.

Furthermore, the reversing mechanism 7 in this embodiment uses a simple conveyor that turns the plate-like object upside down, but this is useful when the plate-like object is being transported vertically and dried by blowing hot air perpendicular to the conveying direction. Therefore, the reversing mechanism may be changed as appropriate to change the front and back or left and right sides of the plate-like object to be dried at any intermediate point in the drying process depending on the conveying state of the plate-like object and the hot air blowing direction.

[Brief explanation of the drawing]

Figures 1 to 3 are diagrams schematically showing one embodiment of the present invention, with Figure 1 being a front view, Figure 2 being a plan view, Figure 3 being an overall side view, and Figure 4 being a board. FIG. DESCRIPTION OF SYMBOLS 1... Drying device, 2... First zone, 3... Second zone, 4... Cooling device, 7... Reversing mechanism, 10... Unit drying device, 12... Endless conveyance belt, 13... Fork , 15,15'...Hot air heating device, 16,16'...Blower fan, 18,1
8'...Exhaust fan, 23, 23', 27, 27'
...Air volume adjustment mechanism, 24, 24'...Blower duct,
25, 25'... Exhaust duct, 31... Plate-shaped object (material to be dried).

Claims (1)

[Claims] 1. The drying device includes a main body of the drying device including an inlet and an outlet for plate-like objects, and a large number of rod-like forks that hold the plate-like objects to be dried in an upright state orthogonal to the direction of travel, erected on the conveying surface. An endless conveyor belt that is driven in circulation between the loading inlet and the unloading outlet of the main body, and an endless conveying belt that is disposed close to each other and facing each other on both sides of an extension of the conveying surface with the endless conveying belt in between, and each of which is high relative to the conveying surface of the endless conveying belt. A hot air blower duct and a hot air exhaust duct having a plurality of air outlets or exhaust ports partitioned in the horizontal direction, and installed at each air outlet and each exhaust port of the hot air blower duct and hot air exhaust duct and whose opening degree is adjusted independently. 1. A drying device for plate-like materials, characterized in that it is equipped with a damper.