JPS5847517B2 - Wood chip classification equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a classification device for removing foreign substances such as metal pieces and stone pieces from wood chips mixed with foreign substances.

For wood chips, we use the ends of logs, offcuts, plywood ears, stripped cores, etc., so we use S-shape rings driven to prevent the ends of logs from cracking, nails for assembling rafts, metal pieces such as wire pieces, etc. They are often contaminated with foreign objects such as shell grains such as barnacles that adhered to wood chips and logs when they were stored at sea level, and pebbles and sand that dug into the skin of the logs when they were stacked at the dump.

When wood chips contaminated with such foreign substances are passed through a defibrator to form wood fibers, and the fibers are heat-press plated using an adhesive to produce fiberboard, the blades of the defibrator may be damaged. It has many drawbacks, such as sparks that can ignite the fibers, causing explosions and fires, and even damaging the saw blade when processing fiberboard.

There are two methods of manufacturing fiberboard: wet and dry, and the former involves transporting wood chips in water.
Foreign matter with a large specific gravity is removed by sedimentation, but in the dry method, the wood chips are blown with air current, so in order to remove foreign matter, a metal detector is installed during transportation, and chips containing metal are discarded. Attempts have been made to attract iron pieces using magnets or magnets placed appropriately in the conveyance path, but the former method has a poor chip yield, and the latter method cannot separate non-ferrous metals.

Furthermore, in both cases, it is impossible to separate nonmetals. SUMMARY OF THE INVENTION In order to solve the problems of the prior art as described above, it is an object of the present invention to provide an apparatus for efficiently classifying foreign substances from wood chips.

The embodiments of the present invention illustrated in the drawings will be described.

(1) In Fig. 1, wood chips are carried out in appropriate amounts from a wood chip silo by a screw conveyor and a belt conveyor nato, and are supplied onto a vibrating conveyor 2 which has a gentler angle than the chip drop port 1 located at the top of the classification device of the present invention. During the vibration process, foreign matter with a high specific gravity gradually settles to the bottom layer of the chips and falls by gravity into the deep and wide classification chamber space from the vertical falling edge of the pipe.

Most of the iron pieces are absorbed and removed by the magnet 3 installed just below the vertical falling edge, but the wood chips containing the remaining foreign objects are absorbed by the friction force and impact caused by the intertwining of the wood chips and foreign objects as they come into contact with the wall surface. The object is caused to fall onto the inclined surface 4 in the falling path 20, which has an angle set to allow sufficient separation due to the force.

It is desirable that the angle of the slope 40 is such that the wood chips do not peel off from the wall or get stuck on the slope, and this will vary depending on the species, moisture content, and shape of the wood chips used, but from experience, 60°±50 is preferred.

A nozzle 5 having a damper 6 is provided at the lower end of this inclined surface 4.

The chips falling from the inclined surface 4, foreign matter and wood chips, fall inside the classification chamber 14, drawing parallax lines a and b depending on the ratio of air resistance and mass of each chip.

At this time, air is force-fed by a blower 15 from the nozzle 5, and air whose speed and volume are adjusted by a damper 6 is blown out in a horizontal direction.

Due to the air flow from this nozzle, foreign objects such as metals and stones with low air resistance/mass fall toward you, drawing a parallax line b, but wood chips with large air resistance/mass draw a parallax line a toward the distance. and fall.

At the falling position of these foreign objects and the falling position of wood chips, there is a foreign object storage chamber 7 having a conveyance device 10, 11 such as a belt conveyor or screw conveyor at the bottom for conveying foreign objects and wood chips to the outside of the classification chamber. and a wood chip storage chamber 8, and an adjuster plate 9 is provided on the boundary line of the compartments, and the apex of the boundary line is extendable and retractable toward the foreign matter chamber side and the wood chip chamber side.

This adjuster plate 9 may be a mechanism that slides along the inner wall surface of one of the storage chambers, or it may be of a damper type that can freely rotate to both sides using the boundary line point as a fulcrum as in the case of Fig. 2. good.

This adjuster plate 9 allows fine adjustment of the separation of foreign matter and wood chips.

On the opposite side of the horizontal nozzle 5 of the classification chamber, wood chips having a particle size that can be used as wood chips are placed in a flapper 1.
The wood flour chamber 12 is separated by a flapper wall or screen so that the wood powder falls into the chip chamber side along the slope of No. 3, but the wood powder, which is in the form of a fine powder and is not suitable for fiberization, passes along with the airflow. This wood powder chamber is connected to a dust collector 16 such as a back filter or cyclone.

Air for powder suction flows through the conduit connecting the powder chamber 12 and the dust collector, but in order to more efficiently perform powder suction and separation, the foreign matter storage chamber 7 and the chip storage chamber 8 are
A duct outlet 17 is installed on the inner wall of the duct and has a built-in damper 19 that adjusts the wind force so as to blow the fine wood powder floating in the classification chamber 14 toward the powder chamber without adversely affecting the falling path of foreign objects and wood chips. It is good to have a

(2) Next, an embodiment of the apparatus of the present invention shown in FIG. 2 will be described.

In the embodiment shown in Fig. 2, the slope 4 in the embodiment shown in Fig. 1 is arranged in two stages to remove foreign matter, low specific gravity wood chips made of low specific gravity tree species or dry wood, and wood that cannot be completely separated from the foreign matter. A first inclined surface 4' for separating the mixed chips from each other by contact friction, etc.; and a second inclined surface 4' for further separating the bond.

In Figure 2, 1/, 2/, 3/, γJ 8'
j 1 0'311', 12', 13', 14', 16
', 20' are the same as in Fig. 1: chip drop port, chip supply section, magnet, foreign matter storage chamber, chip storage chamber, wood chip unloading device, wood powder storage chamber, multi-stage flapper classification chamber, dust collector, drop path. The function is the same as in FIG.

Directly below the first slope 4', a horizontal nozzle 5' is provided for spraying only low-density wood chips far away.

Also, there is a horizontal nozzle 5' directly below the second slope 5'.
will be established.

The horizontal nozzle 5' uses a damper 6 to control the volume and speed of the air blown out from the horizontal nozzle 5' so that the foreign matter is separated into a falling curve b' for wood chips that is not completely separated from the foreign matter and a falling curve a' for the wood chips. ’ to adjust.

15' is the blower. The second horizontal nozzle 5'' is used to sort the foreign matter and wood chips separated by the second ramp 4', which fall down in a falling curve b', into wood chips and foreign matter. It is.

The volume and speed of air blown out from the horizontal nozzle 5'' are adjusted by damper σ'.

15' is the blower. As shown in the figure, the wood chips and foreign objects fall into the foreign object storage chamber 7' and the chip storage chamber 8', respectively, following falling trajectory curves // and b'.

As in the case of FIG. 1, an adjuster plate 9' that swings around the apex of the boundary is provided at the boundary between the foreign matter storage chamber 7' and the chip storage chamber 8'.

Further, by providing an oblique nozzle 17' in the foreign matter storage chamber 7' as in the case of FIG. 1, wood chips attached to foreign matter are separated.

Furthermore, if an adjuster plate 18 is formed in the intermediate layer between the falling curve a' of low specific gravity wood chips on the side of the second slope 4' and the falling curve b' of foreign objects, the separation efficiency can be improved. I can do it.

The upper end of the adjuster plate 18 has a falling curve a'
, b' are extendable and retractable in the direction of the separation point, and the lower end has a direction that guides the falling of chips into the wood chip storage chamber 8'.

Since the present invention has the above-described configuration, its effects can be summarized as follows.

■ Unlike the conventional method of removing foreign matter using metal detectors or magnets, we have adopted classification by air selection, which makes it possible to remove all kinds of foreign matter without reducing chip yield.

It is particularly suitable for dry fiberboard manufacturing.

■ Foreign matter with a high specific gravity is precipitated to the lower layer of chips by the vibrating conveyor 2, iron pieces are removed by the magnet 3, and then classified by air selection, so that foreign matter and wood chips can be efficiently classified.

(2) By forming the inclined surfaces 4', 4' in two stages, the classification efficiency can be further improved.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of a first embodiment of the apparatus of the present invention, and FIG. 2 is a side sectional view of the second embodiment. 1, 1'...Chip drop port, 2, 2'...
... Vibration conveyor, 3, 3'... Magnet, 4, 4', 4'... Inclined surface, 5.
5', ! 5"...Horizontal nozzle, 6, 6'
...Damper, 7, 1'... Foreign matter storage chamber, 8, 8'... Chip storage chamber, 9, 9'...
...Adjuster plate, 10, 10'・
...Foreign object removal device, 1 1, 1 1'...
...Wood chip unloading device, 1 2 , 1 2'・-
...Wood powder storage chamber, 1 3, 1 3'・
...Multi-stage flapper 14,14'...
・Classification room, 15, 15”...Blower, 1
6, 16'... Dust collector, 1 7, 1 7
'...Diagonal nozzle, 18...Adjuster play}, 19,19'...゛...' Damper
20.20'... Falling path.

Claims (1)

[Scope of Claims] 1. The slope of the elongated falling path 20 has a slope 4 having an angle such that the wood chips containing foreign matter fall from the end of the upper chip supply section without being separated or stagnant. A classification chamber 14 has a horizontal nozzle 5 at its lower end that blows out air in a horizontal direction, and rapidly expands diagonally downward in the air blowing direction from vertically below the nozzle, and a nozzle 11 that extends diagonally upward at the bottom of the classification chamber 14. It has a foreign matter storage chamber 7, a wood chip storage chamber 8, and a wood powder storage chamber 12, and on the boundary line between the wood chip storage chamber 8 and the foreign matter storage chamber 7, there are falling curves a and b of wood chips and foreign matter. It has an adjuster plate 9 that can be expanded, contracted and oscillated along the same direction, and on the boundary line between the wood chip storage chamber 8 and the wood powder storage chamber 12, there is a multi-stage flapper 13 for separating the wood chips and powder, or a screen or the like. An apparatus for classifying wood chips contaminated with foreign matter, comprising: an apparatus for classifying wood chips contaminated with foreign substances. 2 The slope is the first slope 4 of the inner wall of the fall path at the top of the classifier
', and a second inclined surface 4' formed on the upper part of the wall of the classification chamber almost vertically below the first inclined surface, and the lower end of the first and second inclined surfaces. A first horizontal nozzle 5' and a second horizontal nozzle 5' are respectively provided in the classification chamber, and the wood screened by the first horizontal nozzle is placed on the side of the second slope in the center of the classification chamber. The apparatus for classifying wood chips mixed with foreign matter as claimed in claim 1, further comprising an adjuster plate 18 whose upper part is extendable and retractable along the lower surface of the falling curve a' of the chips.