JP2001341111A - Apparatus and method for molding fiberboard - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve quality of a fiberboard by quickly discharging a solvent volatilized from a binder solution outside a system in a method wherein a fiber mat in a state of being impregnated with the binder solution is pinched between both molds 11 and 12 and formed into the fiberboard by hot pressing. SOLUTION: At a point of time when the fiber mat 20 is hot pressed for a specific time, many venting space parts 12g open onto the fiber mat 20 are formed to a top force 12 side, and volatilized gaseous solvent is allowed to stay in the space parts 12g. Besides, it is discharged from the space parts 12g outside a system, the gaseous solvent is prevented from staying in the fiber mat 20, and a forming defect is prevented from being generated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an apparatus and a method for forming a fiberboard.

[0002]

2. Description of the Related Art As one method for forming a fiber mat into a fiber board, there is a method in which a fiber mat impregnated with a binder solution is sandwiched between upper and lower molds, hot-pressed, and formed into a fiber board. is there. The molding method of this method is a method adopted when the fibers constituting the fiber mat do not have self-fusing properties. Examples of fibers having such properties include, for example, natural cellulose fibers such as cotton, hemp, and kenaf fibers, and cellulose such as viscose rayon, cupra, and acetate fibers formed by chemically treating woody cellulose. Chemical fibers of the system can be cited.

[0003] However, when the molding method of this method is adopted, a binder solution of a volatile solvent is usually employed as the binder solution, and when molding the fiber mat, the fiber mat impregnated with the binder solution is used. The material is sandwiched between the upper and lower molds and hot-pressed at a temperature at which the solvent evaporates.During this period, the fibers constituting the fiber mat are adhered to each other with a binder which is a solute remaining by evaporating the solvent and having a predetermined shape. It is molded into a board.

[0004]

By the way, in the molding method of this type, a mold having a large number of gas vent holes is adopted as one of the upper and lower molds, and a solvent volatilized when molding the fiber mat is used. Means for discharging to the outside are taken, but during the molding of the fiber mat, the binder solution enters the gas vent hole of the mold, closes the gas vent hole with the binder, and prevents the outflow of the volatile solvent out of the system. In addition, a phenomenon in which the gaseous solvent remains in the fiber mat in the course of molding occurs, and molding failure occurs in the fiber mat.

In order to cope with such a problem, a fiber mat is formed in an open state without clamping both molds, or
Immediately after clamping both molds, release the mold clamping state,
Means are employed in which the molding of the fiber mat is continued in the open state, and the volatile gaseous solvent flows out of the system smoothly. However, when such a forming means is employed, hot pressing on the fiber mat is not performed quickly and sufficiently, and it takes a long time to form a fiber board.

Accordingly, an object of the present invention is to solve these problems in the molding method of the type.

[0007]

The present invention relates to a fiberboard molding apparatus and a fiberboard molding method, and in particular, a fiber mat impregnated with a binder solution is sandwiched between both molds. An object of the present invention is a fiberboard forming apparatus and a fiberboard forming method for hot pressing to form a fiberboard.

Thus, a fiber board forming apparatus according to the present invention comprises a lower mold having a mold surface on an upper surface side and an upper mold having a mold surface on a lower surface side and relatively moving with respect to the lower mold. The solvent volatilized at the front end of the through-hole stays at a retreat position where it is removably attached to a plurality of through-holes provided through the mold surface of the same-type die and retracts from the mold surface side of the same-type die. A punching means for forming a gas release space, a spring means for urging the pressing means toward the mold surface of the upper die to be located at a forward position, and a lower die facing the punching means. There is provided a pushing means provided for receiving the pushing / pulling means and moving the pushing / pulling means back and forth during operation.

The molding apparatus according to the present invention is provided with a suction means for sucking and discharging the solvent which evaporates and stays in the gas vent space formed in each through hole of the upper die. In addition, a punch that advances and retreats through each through hole of the upper die can be used as the punching means, and a hydraulic cylinder such as a hydraulic cylinder or an air cylinder can be used as the pressing means.

A fiberboard molding method according to the present invention is a molding method for molding a fiber mat into a fiberboard using the fiberboard molding apparatus according to the present invention, and includes the following steps. It is characterized by the following.

That is, in the method of forming a fiber board according to the present invention, the upper die is advanced relatively to the lower die, and the pushing means is received by the pushing means, and a binder is provided between the two dies. A first step of positioning a fiber mat in a state of being impregnated with a solution, and further moving the upper mold relative to the lower mold to operate the pushing means to move the upper mold to a lower dead center. A second step of hot pressing the fiber mat for a predetermined time in a state where the upper die is moved to a bottom dead center; and a pressing step of hot pressing the fiber mat for a predetermined time. A fourth step of operating the moving means to retract the pushing means and forming a gas vent space on the mold surface side of each through hole of the upper mold is provided.

In the method for forming a fiber board according to the present invention, the fibers constituting the fiber mat include cotton,
Cellulose-based natural fibers such as hemp and kenaf fibers, and viscose rayon, which is obtained by chemically treating woody cellulose, cupra, and cellulose-based chemical fibers such as acetate fibers can be employed, and the fiber mat is impregnated. As the binder solution, a binder solution of a volatile solvent can be adopted, as such a binder solution,
It is preferable to employ a solution obtained by dissolving acetate in acetone. In addition, synthetic fibers other than natural fibers and chemical fibers can be used as the fibers constituting the fiber mat.

[0013]

In the method of forming a fiber mat into a fiber board using the forming apparatus according to the present invention, a pushing means such as a hydraulic cylinder or an air cylinder is operated during the formation of the fiber mat. By retracting the pushing means from the forward position, a gas vent space in which the volatile solvent stays can be formed on the mold surface side of each through hole of the upper mold. For this reason, the gaseous solvent volatilized during the molding of the fiber mat flows into the degassing space and stays in a gaseous state, and part of the gaseous solvent passes through the gaps between the through-holes of the upper die and the system. Spills out.

As described above, according to the molding method employing the fiberboard molding apparatus according to the present invention, the gaseous solvent volatilized during the molding of the fiber mat stays in the degassing space and stays there. Since the gaseous solvent is discharged out of the system, the invasion of the gaseous solvent into the fiber mat during molding is prevented or largely suppressed, and the fiber mat does not cause molding failure, A good quality fiber board can be provided. Further, at the time of molding the fiber mat, since the molding can be completed in a state where both the upper and lower molds are sufficiently clamped, the time required for molding the fiber mat can be greatly reduced.

As the fiber board molding apparatus according to the present invention, a molding apparatus having suction means for sucking and discharging gaseous solvent staying in the gas vent space formed in each through hole of the upper die is adopted. For example, by operating the suction means, the gaseous solvent volatilized during the molding of the fiber mat can be sucked and forcibly discharged out of the system,
It is possible to efficiently recover the volatile solvent.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. 1 to 4 show operating states of the forming apparatus 10 in different steps in a forming method employing the fiber board forming apparatus 10 according to an example of the present invention. FIG.
2 shows a state in which the fiber mat 20 is set between the lower mold 11 and the upper mold 12 constituting the molding apparatus 10 (first step). FIG. FIG. 3 shows a state where the upper mold 12 is located in the middle of the dead center (second step).
FIG. 4 shows a state in which the upper die 12 is located at the bottom dead center, and the punch 13 forming the molding apparatus 10 is moved up by a predetermined amount while the upper die 12 is located at the bottom dead center. Is shown (fourth step).

Each of these steps shows the order of steps used in the method of forming a fiber board according to the present invention.
2 corresponds to the first step defined in the present invention, the third step shown in FIG. 3 corresponds to the second step and the third step defined in the present invention, and the second step shown in FIG. Four steps correspond to the fourth step defined in the present invention.

The molding apparatus 10 includes a lower mold 11 and an upper mold 1.
2. It comprises a punch 13 as a punching means, a plurality of compression springs 14 as a spring means, and a plurality of hydraulic cylinders 15 as a pushing means. In the lower mold 11, a concave mold surface 11b is formed on the upper surface of the mold body 11a, and each hydraulic cylinder 15 is formed on the outer edge of the mold surface 11b.
Are arranged upright.

The upper mold 12 comprises a mold body 12a and a molding pad 1.
2b, and the mold body 12a has a recess 1 opening downward.
2c, and a molding pad 12b is integrally attached to the lower surface of the mold body 12a. Thus, a space is formed between the mold body 12a and the molding pad 12b. A lower mold 1 is provided on the lower surface of the molding pad 12b.
A convex mold surface 12d corresponding to one mold surface 11b is formed, and a large number of through-holes 12e are formed in the formation portion of the mold surface 12d. A plurality of insertion holes 12f into which the respective hydraulic cylinders 15 arranged in the lower die 11 are inserted are formed in the outer edge of the die surface 12d in a penetrating state.

The punch 13 has a flat holder 13a.
Are provided with a large number of rod portions 13b on the lower surface side. The punch 13 is assembled to the molding pad 12b of the upper mold 12 before the molding pad 12b is assembled to the mold main body 12a, and each rod portion 13b is attached to each through hole 12e of the molding pad 12b by an upper surface. It is inserted and assembled so that it can advance and retreat from the side. Therefore, the punch 13 is assembled to the mold body 12a integrally with the molding pad 12b. At the time of assembling, a plurality of compression springs 14 are interposed in the recesses 12c of the mold body 12a. 12b is integrally attached to the mold body 12a. In the punch 13 in the assembled state, each compression spring 14 is in contact with the upper surface of the holder 13a to urge the punch 13 downward, and each rod 13b is located at the forward position, and their tips are It faces the mold surface 12d on the lower surface side of the molding pad 12b.

The pushing means comprises a plurality of hydraulic cylinders 15,
The hydraulic cylinder 15 comprises a control unit 16 for controlling the operation of the hydraulic cylinder 15. The hydraulic cylinder 15 is slidably fitted into the cylinder 15 a and
and a piston rod 15b protruding from the upper end of the piston rod 15a. The control unit 16 includes the hydraulic cylinder 15
The piston rod 15b moves forward and backward with respect to the cylinder portion 15a by controlling the supply and discharge of hydraulic oil to and from the oil chamber in the cylinder portion 15a. The piston rod 15b projects from the cylinder portion 15a when moving forward, and the cylinder moves when retracting. Buried in the part 15a.

In order to form a fiber mat into a fiber board using the molding apparatus 10, a fiber mat impregnated with a binder solution is used as the fiber mat.
FIG. 1 shows an example of a fiber mat. The fiber mat 20 is obtained by applying a binder solution 23 between the layers of the kenaf fiber webs 21 and 22. As the binder solution 23, for example, a solution of a volatile solvent obtained by dissolving acetate in acetone is adopted. .

In the method of forming the fiber mat 20 into a fiber board using the forming apparatus 10, the fiber board is formed by sequentially applying the fiber mat 20 to the steps shown in FIGS. .

In order to mold the fiber mat 20, first, as shown in the first step of FIG. 1, the fiber mat 20 is set between the two dies 11 and 12 of the molding apparatus 10 which are separated from each other. After the preparation is completed, the punch 13 is received by the piston rod 15b of each hydraulic cylinder 15 with respect to the lower mold 11 by lowering the upper mold 12 by a predetermined amount as shown in the second step of FIG. Move forward. In this state, the mold surface 12d of the molding pad 12b of the upper mold 12 is
The molding is started by contacting the upper surface of the “0”.

In this state, the upper die 12 is further lowered while the hydraulic cylinder 15 is operated and the piston rod 15b is buried in the cylinder part 15a, so that the lower dead center is reached as shown in the third step of FIG. Position. Thereby, both types 1
The molds 1 and 12 are completely clamped, and the fiber mat 20 is sandwiched between the molds 11 and 12 and subjected to a hot press for a predetermined time.
The hot pressing of the fiber mat 20 in this state is, for example, 10
It is performed for 10 seconds at 0 ° C., and in a state where the hot press is continued, each hydraulic cylinder 15 is operated to operate the piston rod 15.
b is projected from the cylinder portion 15a.

As a result, as shown in the fourth step of FIG. 4, the punch 13 is pushed upward against each compression spring 14 by the action of each hydraulic cylinder 15, and the upper die 1 is pressed.
The fiber mat 2 in the middle of molding is formed on the tip side of each through hole 12e.
A large number of degassing spaces 12g are formed on the upper surface side of 0, and this state is maintained, and the hot press is continued for a predetermined time, for example, about 2 minutes. During this time, the gaseous solvent volatilized from the fiber mat 20 flows into each degassing space 12g and stays in a gaseous state, and a part of the gaseous solvent is separated from the rod portion 13b of each through hole 12e of the upper die 12. Through the system.

By the completion of the fourth step, the fiber mat 2
0 is molded into a fiber board having a shape corresponding to the mold surfaces of both molds 11 and 12. When the fourth step is completed, the upper mold 12
To the top dead center. As a result, the upper mold 12 retreats from the lower mold 11 to separate the punch 13 from the piston rod 15b of each hydraulic cylinder 15, and the punch 13 causes the holder 13a to contact the upper surface of the forming pad 12b by the action of each compression spring 14. Then, the molding apparatus 10 returns to the state shown in the first step of FIG.

As described above, according to the molding method employing the fiber board molding apparatus 10 according to the present invention, the fiber mat 2
Since the gaseous solvent volatilized in the course of molding is retained in the degassing space 12g, and the retained gaseous solvent is discharged out of the system, the fiber mat during the molding of the gaseous solvent is removed. It is possible to provide a fiber board of good quality without preventing or largely suppressing the intrusion of the fiber board 20 into the interior of the fiber board 20 and without causing molding defects. Further, at the time of molding the fiber mat 20, since the molding can be completed in a state where both the dies 11, 12 are sufficiently clamped, the time required for molding the fiber mat 20 can be greatly reduced.

FIG. 5 shows another example of an apparatus for forming a fiber board according to the present invention. The molding device 10a includes:
The above-described molding apparatus 10 is provided with suction means,
As the suction means, a suction pump 17 is employed. The suction pump 17 is connected to the recess 12 c of the mold body 12 a of the upper mold 12. By driving the suction pump 17, the gas that volatilizes during the formation of the fiber mat 20 and stays in the degassing space 12 g. Solvent in the upper mold 12
It can be sucked through the recess 12c of 2a and forcedly discharged out of the system. In this state, the gaseous solvent can be efficiently recovered.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an operation state in a first step of a molding apparatus according to an example of the present invention.

FIG. 2 is a longitudinal sectional view showing an operation state in a second step of the molding apparatus.

FIG. 3 is a longitudinal sectional view showing an operation state in a third step of the molding apparatus.

FIG. 4 is a longitudinal sectional view showing an operation state in a fourth step of the molding apparatus.

FIG. 5 is a longitudinal sectional view showing an operation state in a fourth step of a molding apparatus according to another example of the present invention.

[Explanation of symbols]

10, 10a molding apparatus, 11 lower mold, 11a mold body, 11b mold surface, 12 upper mold, 12a mold body, 12
b: molding pad, 12c: recess, 12d: mold surface, 12e
... through-hole, 12f ... insertion hole, 12g ... degassing space,
13 ... punch, 13a ... holder part, 13b ... rod part, 14 ... compression spring, 15 ... hydraulic cylinder, 15
a: cylinder part, 15b: piston rod, 16: control unit, 17: suction pump, 20: fiber mat, 2
1, 22 ... fiber web, 23 ... binder solution.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Michi Kobe, Inventor F-term (reference) 2B260 AA12 BA07 BA15 BA19 CA02 CC01 DA09 DC05 EA03 EA11 EB02 EB07 EB15 EB19 EC08 4L047 AA08 AA12 AA28 AB02 BA15 CB09 EA01

Claims (8)

[Claims] 1. A fiberboard forming apparatus for forming a fiberboard in which a fiber mat impregnated with a binder solution is sandwiched between two molds and hot-pressed to form a fiberboard. A lower mold having a mold surface, an upper mold having a mold surface on the lower surface side and moving relatively to the lower mold, and a plurality of through holes provided through the mold surface of the same mold. A punching means for forming a degassing space in which the solvent volatilized at the front end of the through-hole is retained at a retracted position which is retreated from the mold surface side of the same mold as the above-mentioned mold; Spring means for urging the mold surface side to be located at the forward position, and being provided on the lower mold so as to face the pushing means, receiving the pushing means and moving the pushing means back and forth during operation. An apparatus for forming a fiberboard, comprising a pushing means. 2. The molding apparatus according to claim 1, wherein the molding apparatus sucks and discharges a solvent that volatilizes and stays in a degassing space formed in each through hole of the upper die. An apparatus for forming a fiber board, comprising: 3. A fiber as set forth in claim 1, wherein said punching means is a punch which advances and retreats through each through hole of said upper die, and said pushing means is a fluid pressure cylinder. Board molding equipment. 4. A molding method for molding a fiber mat into a fiber board using the molding device according to claim 1 or 2, wherein the upper mold is advanced relatively to the lower mold to form the press. A first step in which the pressing means is received by the pushing means to position the fiber mat in a state in which the binder solution is impregnated between the two dies, and the upper die is further relatively moved with respect to the lower die. A second step of moving the upper die to the bottom dead center by operating the pushing means by moving forward, and a second step of hot-pressing the fiber mat for a predetermined time while the upper die is shifted to the bottom dead center. Step 3, and at the time when the fiber mat is hot-pressed for a predetermined time, the pushing means is operated to retract the pushing means to form a gas vent space on the mold surface side of each through hole of the upper mold. A method of forming a fiber board, comprising a fourth step. . 5. The molding method according to claim 4, wherein the fibers constituting the fiber mat are cellulosic natural fibers. 6. A molding method according to claim 4, wherein the fibers constituting said fiber mat are cellulose-based chemical fibers. 7. The fiberboard molding method according to claim 4, wherein the binder solution impregnated in the fiber mat is a volatile solvent solution. 8. The molding method according to claim 7, wherein the binder solution is a solution of a volatile solvent obtained by dissolving acetate in acetone.