JPH1151561A - Compression dehydrator for wood - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform dehydration quickly and to discharge the oozed out water content quickly by mounting a rectangular timber on a basic material plate provided with a water content discharging groove, compressing the rectangular timber from the upper and side faces thereof and discharging the oozed out water content. SOLUTION: A member to be dried, i.e., a rectangular timber 1, is supplied by a supply conveyor 2 into a compression dehydrator for wood and mounted on a basic material plate 3. The rectangular timber 1 is carried into the compression dehydrator and subjected to lateral positional adjustment by means of a horizontal movement air cylinder 4. Subsequently, a longitudinal compression hydraulic air cylinder 6 is operated to abut a longitudinal compression plate 7 against the upper surface of the rectangular timber 1 and a lateral compression hydraulic air cylinder is operated to abut a lateral compression plate against the side surface of the rectangular timber 1 thus applying a compressive force to the upper and side surfaces. The basic material plate 3 comprises a large number of metal plates having grooves in the surface and the metal plates are arranged vertically to form grooves for discharging the oozed out water content.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to preliminary dehydration for drying wood, and relates to the elasticity, viscosity, and the like inherently possessed by wooden timber and building structural materials, so-called pillars, foundations, tension, and digits. The present invention relates to a compression dewatering apparatus for wood using elasticity and kinetic elasticity.

[0002]

2. Description of the Related Art Conventionally, wood used as a structural material for a building is used after it has been cut down and is sufficiently dried, but is usually forcibly dried using a dryer. As the drying progresses, the surface layer of the wood is dried quickly, and the water content of the surface layer decreases. When the moisture content of the surface layer decreases, the thermal conductivity of the surface layer decreases, the heat conduction to the interior of the wood becomes poor, and it takes time to dry the interior. As a result, there is a large difference in shrinkage between the surface layer portion and the inside of the wood, and a crack A is generated (see FIG. 5). In particular, in the case of domestically produced squared timber, the white ring-shaped portion B prevents drying of the core. As a countermeasure, cut C
And a method for facilitating drying is adopted in some areas (see FIG. 6). This method has not been widely used at present because the place where it is used as a building structural material is limited.

[0003] In order to dry without such cuts and without causing cracks, a core material (105 x 105 x 3600 mm) made of domestically produced cedar thinning core and having an average water content of 100% is used as the core. About 600-700 to dry to about 18%
Takes time (25-30 days). Such a drying method requires an enormous amount of expenses including the amortization cost of equipment such as a drying facility and other drying costs. For example, Nissan 50 m ³ approximately mid-sized timber plants, in order to dry the water content of about 18% to correctly core, not must comprise more than 10 to 20 groups of the dryer, the cost impossible is there.

[0004] Therefore, in order to counter cheap imported foreign materials,
Keep the drying time at about 240-250 hours (almost 10 days)
The reality is that the surface layer at a depth of about 10 to 15 mm from the surface is dried to about 20%, and the core is dried to about 30 to 50%, and then shipped to the market as artificially dried materials. In addition, since wood turns black when sufficiently dried, many are shipped in an insufficiently dried state where only the surface is dried with an emphasis on appearance. Such inadequate drying can cause kinks and cracks and lead to complaints, so some major home builders either use steel frames, or even at higher prices, glulam (laminate). The use of wood is increasing, and the use of domestic timber is becoming more and more difficult.

[0005] On the other hand, in Japan, conifers have been planted as fast-growing tree species after the war, and fir trees, pine trees and pine trees have been planted in Hokkaido, and cedar and hinoki have been mainly planted in Honshu. Therefore, in the future,
An enormous amount of production mainly from these timber is inevitable.
However, as for softwoods, rice pine and spruce are imported from the United States,
In addition, imported from South America, New Zealand, Sweden, Russia, etc., these foreign materials account for 75% of domestic consumption. Therefore, in order to use domestic softwoods, which are expected to produce a huge amount in the future, as building materials, there is a strong demand for easy and inexpensive drying of wood.

[0006]

SUMMARY OF THE INVENTION The inventor of the present invention has focused on the fact that in order to efficiently dry a square bar in a short number of days and to sufficiently dry the core, it is sufficient to dehydrate the square bar prior to heating and drying. An object of the present invention is to provide a compression dewatering apparatus for wood which can be well dewatered and does not cause twisting or cracking during heating and drying.

[0007]

According to the present invention, there is provided an apparatus for compressing and dewatering wood, comprising: a base plate on which the timber is placed; a top compression means for compressing the timber from above; and a side compression means for compressing the side surfaces of the timber. Wherein the base plate has a drainage groove for discharging water oozing out by compression.

[0008] The base plate is formed by vertically arranging a plurality of metal plates having concave grooves serving as drainage grooves for water oozing out by compression. Further, below the base plate, lifting means for lifting the wood is provided,
When lifting or placing the wood, the tip of the lifting means passes through a plurality of through holes provided in the base plate,
It is provided to enter and exit.

Using a compression dehydrating apparatus for wood having the above-described structure, a bar having a reduced water content is heated in a drying oven at a maximum temperature of 120 ° C. for 40 to 60 hours including a temperature rise and a cooling time. By doing so, it is dried sufficiently in an extremely short time to an average water content of 20% or less.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION A compression dewatering apparatus for wood according to the present invention will be described in detail below. FIG. 1 is a front view showing a compression dewatering apparatus for wood of the present invention, FIG. 2 is a side view of FIG.
FIG. 3 is a plan view. FIG. 4 is a sectional view showing a base plate used in the compression dewatering apparatus of the present invention. In addition, the compression dewatering apparatus for wood of the present invention is not limited to the embodiments shown in FIGS. 1 to 4, and various embodiments are possible. After dehydration using the compression dehydration apparatus of the present invention, drying by heating is preferable because drying in a short number of days is possible, but natural drying may also be used.

First, a timber 1 to be dried is supplied by a supply conveyor 2 into a compression and dewatering device for wood, and is placed on a base plate 3. The position of the timber 1 is detected by an optical sensor (not shown), and is carried to a predetermined position. The timber 1 carried into the compression / dehydration apparatus is moved by a horizontally moving air cylinder 4 to a horizontal fixing plate 5.
Is moved in the lateral direction through the, and the position is adjusted.
When the position adjustment is completed, the horizontally moving air cylinder 4 retreats to the original position. Next, the vertical compression hydraulic cylinder 6
After the vertical compression plate 7 is brought into contact with the upper surface of the square bar 1, the horizontal compression hydraulic cylinder 8 is activated,
The lateral compression plate 9 is brought into contact with the side surface of the square bar 1. In this way, the compressive force is applied to the upper surface and the side surface of the rectangular bar 1 by the vertical compression plate 7 and the horizontal compression plate 9.

The square bar 1 exudes moisture contained by compression. When the compressive force is released, the exuded moisture
And the square timber 1 is restored to its original state. In order to prevent this, the base plate 3 is formed by densely and vertically arranging a large number of metal plates having grooves formed on the surface, and the grooves on the surface of the metal plate are drainage grooves for water oozing out by compression. Is formed. Although various forms are possible for the formation of the concave groove on the surface of the metal plate, an example of the base plate 3 is shown in FIG. 4 in a partially enlarged longitudinal sectional view. Reference numeral 10 denotes a grooved metal plate, and reference numeral 11 denotes a metal plate as a core material. The groove of the grooved metal plate 10 can be easily formed by press working, and the metal plate to be used is preferably a stainless material having a thickness of 1.0 to 1.5 mm, for example, SUS304. The water oozed out by the compression flows down through the concave groove of the grooved metal plate 10 and the gap between the grooved metal plate 10 and the metal plate 11, and is drained.

When the dehydration is completed, the vertical compression hydraulic cylinder 6 and the horizontal compression hydraulic cylinder 8 retreat to their original positions, respectively, and the compression force is released. Dehydrated square timber 1
Is shifted upward by the lifting air cylinder 13 and pushed out onto the transport conveyor 12 by the next square material supplied by the supply conveyor 2. The lifting air cylinder 13 has a tip portion which enters and exits through a plurality of through holes provided in the base plate when lifting or placing the wood. Reference numeral 14 in the drawing is a slide guide for preventing lateral blur.

The compressed and dewatered square bar 1 is transported to the conveyor 12.
It is transported above, and the maximum temperature is 120 ℃ in the next drying oven.
By heat-treating for 40 to 60 hours including the time of temperature rise and cooling, it is dried to an average water content of 20% or less.

The compression hydraulic cylinders 6 and 8 may be of a pneumatic type, but are preferably of a hydraulic type capable of easily obtaining a larger force. , Gauge pressure 110 to 180 kg / c
m ² is preferable. Within this range, fine cracks can be generated inside the square bar without greatly exceeding the elastic limit of the square bar 1, and drying can be promoted. When compressed and dehydrated under such conditions, even a square timber 1 having an average moisture content of 120%
It is reduced to about 80 to 110%.

The compressive load applied to the bar is not allowed to greatly exceed the elastic limit of the bar, and is set within a range that substantially restores the original size when the load is removed. At this time, it is preferable to employ a compressive load close to the elastic limit or a compressive load slightly exceeding the elastic limit. When a compressive load is applied, the square bar gradually deforms after instantaneous deformation and causes creep, but creep recovers when the compressive load is removed. On the other hand, when the compressive load exceeds the creep limit, creep rupture occurs. For this reason, when a compressive load is applied to near the creep limit, a number of fine cracks begin to form in the internal structure of the bar. The size of the cracks generated at this time is controlled by controlling the compression load, and the wood is inherently included in its tissue structure
0.5 to 0.8mm. Adjusting the crack size to this extent has no effect on the strength of the wood. This crack facilitates the movement of water from the inner layer to the surface during heating and drying, and accelerates drying, enabling drying on short days. Further, the present invention will be specifically described based on examples.

[0017]

[Example] Size is 110 × 110 × 3600mm, average moisture content
130% of the cedar thinning cored squared timber 1 was fed from the supply conveyor 2 into the compression and dewatering device for wood, and was placed on the base plate 3. Air cylinder 4 (gauge pressure)
At 70 kg / cm ² ), it was moved in the horizontal direction via the horizontal fixing plate 5 to adjust the position of the bar 1. Next, the vertical compression hydraulic cylinder 6 (gauge pressure 150 kg / cm ² ) is actuated to bring the vertical compression plate 7 into contact with the upper surface of the square bar 1, and then the horizontal compression hydraulic cylinder 8 (gauge pressure 130 k
g / cm ² ), the lateral compression plate 9 was brought into contact with the side surface of the bar 1, and a compressive force was applied to the top and side surfaces of the bar 1. At this time, the bar 1 was compressed to about 90 × 90 mm in cross section, but was restored to the original size by releasing the compressive force. After compression dewatering for about 1 minute, the average moisture content of the square bar 1 is 100%
Had become.

The dehydrated square bar 1 was transferred to a drying oven, gradually heated, kept at 120 ° C. for 24 hours, and allowed to cool naturally and taken out. The time required for drying is approximately 50 hours for two days. The treated timber 1 had an average moisture content of 18%, no cracks or distortions, and had a strength equivalent to that of the material naturally dried by a conventional method.

[0019]

As described above, by applying a compressive load to the top and side surfaces of the square bar, it is possible to efficiently compress and dehydrate, and the exuded water flows down through the concave grooves and gaps of the base plate. , Drained quickly. By heating and drying using the compressed and dewatered square wood, the square wood is made of, for example, a 100% moisture-containing softwood cored square wood.
Conventionally 600-700 hours (25-30
Days), it took only 50-70 hours (2-3 days), and in a very short period of time, it was sufficiently dried without twisting.

[Brief description of the drawings]

FIG. 1 is a front view showing a compression dewatering apparatus for wood of the present invention.

FIG. 2 is a side view of the compression dewatering apparatus for wood shown in FIG.

FIG. 3 is a plan view of the compression dewatering apparatus for wood shown in FIG. 1;

FIG. 4 is a partially enlarged longitudinal sectional view showing a base plate used in the present invention.

FIG. 5 is a cross-sectional view showing cracks generated when the cored squared material is dried.

FIG. 6 is a cross-sectional view showing a cored squared material that has been cut in advance to facilitate drying.

[Explanation of symbols]

 1 ········································································· ············································ Horizontal Orientation fixed plate, 6 ······························· Vertical compression plate, 8 ················································································· ... Grooved metal plate, 11 ... Metal plate, 12 ... ... Transport conveyor, 13 ... Over cylinder, 14 · · · · · · slide guide.

Claims (3)

[Claims] 1. A base plate on which a square bar is placed, an upper surface compressing means for compressing the square bar from above, and a side compressing means for compressing a side surface of the square bar, wherein the base plate removes moisture oozing out by compression. A compression dewatering device for wood, comprising a drain for discharging. 2. The apparatus for compressing and dewatering wood according to claim 1, wherein said base plate is formed by vertically arranging a plurality of metal plates having concave grooves serving as drainage grooves for water oozing out by compression. 3. A lifting means for lifting wood is provided below the base plate. When lifting or placing the wood, a tip of the lifting means is provided on a plurality of base plates provided on the base plate. The compression dewatering device for wood according to claim 1, wherein the device enters and exits through the through hole.