JP4264184B2 - Fiber board molding apparatus and molding method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fiber board molding apparatus and molding method.
[0002]
[Prior art]
As a method for forming the fiber mat into the fiber board, there is a method in which the fiber mat impregnated with the binder solution is sandwiched between the upper and lower molds and hot pressed to form the fiber board. The molding method of this method is a method adopted when the fibers themselves constituting the fiber mat do not have self-bonding properties. Examples of fibers having such properties include cellulose-based natural fibers such as cotton, hemp, and kenaf fibers, and celluloses such as viscose rayon, cupra, and acetate fibers formed by chemically treating wood-based cellulose. Mention may be made of the chemical fibers of the system.
[0003]
Thus, when adopting the molding method of this method, a binder solution of a volatile solvent is usually adopted as the binder solution, and when molding the fiber mat, the fiber mat impregnated with the binder solution is divided into upper and lower molds. It is hot-pressed at a temperature at which the solvent is volatilized by being sandwiched between them, and while the fibers constituting the fiber mat are bonded to each other with a binder that is a solute remaining by volatilizing the solvent, It is to be molded.
[0004]
[Problems to be solved by the invention]
By the way, in the molding method of this system, a means having a large number of vent holes is adopted as one of the upper and lower molds, and means for discharging the solvent that volatilizes when molding the fiber mat out of the system is adopted. In the middle of molding of the fiber mat, the binder solution enters the vent hole of the mold and closes the vent hole by the binder, thereby preventing the volatilized solvent from flowing out of the system. A phenomenon of remaining in the fiber mat occurs, and molding failure occurs in the fiber mat.
[0005]
In order to cope with such problems, the fiber mat is molded in an open state without clamping both molds, or the mold clamped state is released immediately after both molds are clamped once, and the fiber mat is molded in an open state. In order to smoothly flow out the vaporized gaseous solvent out of the system. However, when such a forming means is adopted, the hot pressing on the fiber mat is not performed quickly and sufficiently, and it takes a long time to form the fiber board.
[0006]
Therefore, an object of the present invention is to solve these problems in the molding method of the method.
[0007]
[Means for Solving the Problems]
The present invention relates to a fiber board molding apparatus and a fiber board molding method, and in particular, a fiber mat impregnated with a binder solution is sandwiched between both molds and hot pressed to form the fiber board. Therefore, the fiber board forming apparatus and the fiber board forming method are intended for application.
[0008]
Thus, the fiber board molding apparatus according to the present invention includes a lower mold having a mold surface on the upper surface side, an upper mold having a mold surface on the lower surface side and advanced and retracted relative to the lower mold. A degassing space in which a solvent volatilized at the front end of the through hole stays at a retracted position that is assembled in a plurality of through holes provided through the mold surface of the mold so as to be able to advance and retract. A punching means for forming a portion, a spring means for urging the punching means toward the mold surface of the upper mold, and a forward position, and a lower mold provided to face the punching means. The punching means is provided for receiving the punching means and moving the punching means back and forth during operation.
[0009]
The molding apparatus according to the present invention may have a configuration including suction means for sucking and discharging the solvent that volatilizes and stays in the gas vent space formed in each through hole of the upper mold. Moreover, a punch that advances and retreats each through hole of the upper mold can be adopted as the punching means, and a hydraulic cylinder such as a hydraulic cylinder and an air cylinder can be adopted as the pushing means.
[0010]
The fiber board molding method according to the present invention is a molding method for molding a fiber mat into a fiber board using the fiber board molding apparatus according to the present invention, and includes the following steps. It is what.
[0011]
That is, in the fiberboard molding method according to the present invention, the upper die is moved forward relative to the lower die, the punching means is received by the pushing means, and the binder solution is impregnated between the two molds. A first step of positioning the fiber mat in a state of being moved, and the upper die is further advanced relative to the lower die to operate the pushing means to move the upper die to the bottom dead center. A second step, a third step in which the fiber mat is hot-pressed for a predetermined time in a state in which the upper mold is moved to the bottom dead center, and the pushing means at the time when the fiber mat is hot-pressed for a predetermined time. It is characterized by comprising a fourth step of operating and retreating the punching means to form a gas vent space on the mold surface side of each through hole of the upper mold.
[0012]
In the fiber board molding method according to the present invention, the fibers constituting the fiber mat include viscose rayon and cupra obtained by chemically treating cellulose-based natural fibers such as cotton, hemp and kenaf fibers, and wood-based cellulose. Cellulosic chemical fibers such as acetate fibers can be employed, and the binder solution impregnated into the fiber mat can be a volatile solvent binder solution. As the binder solution, acetate can be used. It is preferable to employ a solution formed by dissolving in acetone. In addition, as a fiber which comprises the said fiber mat, a synthetic fiber can also be employ | adopted besides a natural fiber or a chemical fiber.
[0013]
[Operation and effect of the invention]
In the method of forming a fiber mat into a fiber board by employing the forming apparatus according to the present invention, the pushing means such as a hydraulic cylinder and an air cylinder is operated during the forming of the fiber mat to move the punching means from the forward position. By retreating, a degassing space in which a 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 that volatilizes during the formation of the fiber mat flows into the gas vent space and stays in the gas state, and a part of the solvent passes through the gap between the upper die through-hole punching means. It flows out.
[0014]
Thus, according to the molding method employing the fiber board molding apparatus according to the present invention, the gaseous solvent that volatilizes during the molding of the fiber mat stays in the degassing space, and the retained gaseous state Since the solvent is discharged out of the system, intrusion into the fiber mat during the molding of the gaseous solvent is prevented or greatly suppressed, and there is no molding defect in the fiber mat, and good quality Fiberboard can be provided. Further, when the fiber mat is molded, the molding can be completed in a state where the upper and lower molds are sufficiently clamped, so that the time required for molding the fiber mat can be greatly shortened.
[0015]
If the molding apparatus having the suction means for sucking and discharging the gaseous solvent staying in the gas vent space formed in each through hole of the upper mold is adopted as the fiber board molding apparatus according to the present invention, By operating the means, it is possible to suck the gaseous solvent that volatilizes during the molding of the fiber mat and forcibly discharge it out of the system, and to efficiently recover the volatilizing solvent.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described with reference to the drawings. 1 to 4 show operating states in different steps of the forming apparatus 10 in a forming method employing the fiber board forming apparatus 10 according to an example of the present invention. FIG. 1 shows a state (first step) in which a fiber mat 20 is set between a lower mold 11 and an upper mold 12 constituting the molding apparatus 10, and FIG. 2 advances the upper mold 12 relative to the lower mold 11. FIG. 3 shows a state where the upper die 12 is located at the bottom dead center (third step), and FIG. 4 shows a state where the upper die 12 is at the bottom dead center. The state (4th process) in which the punch 13 which comprises the shaping | molding apparatus 10 was moved up predetermined amount and was located in the retreat position in the state located in FIG.
[0017]
Each of these steps shows the order of steps taken in the fiber board molding method according to the present invention, and the second step shown in FIG. 2 corresponds to the first step defined by the present invention, and FIG. The third step shown corresponds to the second step and the third step defined in the present invention, and the fourth step shown in FIG. 4 corresponds to the fourth step defined in the present invention.
[0018]
The molding apparatus 10 includes a lower mold 11, an upper mold 12, punches 13 that are punching means, a plurality of compression springs 14 that are spring means, and a plurality of hydraulic cylinders 15 that are pushing means. The lower mold 11 has a concave mold surface 11b formed on the upper surface of the mold main body 11a, and each hydraulic cylinder 15 is arranged upright on the outer edge of the mold surface 11b.
[0019]
The upper mold 12 includes a mold body 12a and a molding pad 12b. The mold body 12a includes a recess 12c that opens downward, and the molding pad 12b is integrally assembled on the lower surface side of the mold body 12a. It is configured. Thereby, a space is formed between the mold body 12a and the molding pad 12b. A convex mold surface 12d corresponding to the mold surface 11b of the lower mold 11 is formed on the lower surface of the molding pad 12b, and a large number of through holes 12e are formed at the formation site of the mold surface 12d. A plurality of insertion holes 12f into which the hydraulic cylinders 15 disposed in the lower mold 11 are inserted are formed in the outer edge portion of the mold surface 12d in a penetrating state.
[0020]
The punch 13 includes a large number of rod parts 13b on the lower surface side of the flat holder part 13a. 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 body 12a, and each rod portion 13b is attached to each through hole 12e of the molding pad 12b on the upper surface. It is inserted and assembled from the side so that it can move forward and backward. Therefore, the punch 13 is assembled to the mold main body 12a integrally with the molding pad 12b. However, when assembling, the plurality of compression springs 14 are interposed in the recesses 12c of the mold main body 12a. 12b is integrally assembled to the mold body 12a. In the assembled punch 13, the compression springs 14 are in contact with the upper surface of the holder portion 13 a to urge the punch 13 downward, the rod portions 13 b are positioned at the forward movement positions, and the tips thereof are It faces the mold surface 12d on the lower surface side of the molding pad 12b.
[0021]
The pushing means includes a plurality of hydraulic cylinders 15 and a control unit 16 that controls the operation of the hydraulic cylinders 15. The hydraulic cylinders 15 are slidably fitted into the cylinder portions 15a and 15a. The piston rod 15b protrudes from the upper end of 15a. The control unit 16 controls the supply and discharge of hydraulic oil to and from the oil chamber in the cylinder portion 15a of the hydraulic cylinder 15, and moves the piston rod 15b forward and backward with respect to the cylinder portion 15a. It protrudes from the portion 15a and is buried in the cylinder portion 15a when retreating.
[0022]
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 employed 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 layers of the kenaf fiber webs 21 and 22. As the binder solution 23, for example, a volatile solvent solution obtained by dissolving acetate in acetone is employed. .
[0023]
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 attaching the fiber mat 20 to the steps shown in FIGS.
[0024]
In order to form the fiber mat 20, first, as shown in the first step of FIG. 1, the fiber mat 20 is set between the two molds 11 and 12 in the state of being separated from each other, and the preparation for molding is completed. Then, as shown in the second step of FIG. 2, the upper die 12 is lowered by a predetermined amount and advanced with respect to the lower die 11 until the punch 13 is received by the piston rod 15 b of each hydraulic cylinder 15. . In this state, the mold surface 12d of the molding pad 12b of the upper mold 12 comes into contact with the upper surface of the fiber mat 20, and molding is started.
[0025]
In this state, the upper die 12 is further lowered in a state where the hydraulic cylinder 15 is operated and the piston rod 15b is buried in the cylinder portion 15a, and is positioned at the bottom dead center as shown in the third step of FIG. As a result, the molds 11 and 12 are completely clamped, and the fiber mat 20 is sandwiched between the molds 11 and 12 and subjected to hot pressing for a predetermined time. The hot pressing of the fiber mat 20 in this state is performed, for example, at 100 ° C. for 10 seconds, and with the hot pressing being continued, each hydraulic cylinder 15 is operated to cause the piston rod 15b to protrude from the cylinder portion 15a.
[0026]
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 tip of each through hole 12 e of the upper mold 12. A large number of degassing spaces 12g opened on the upper surface side of the fiber mat 20 being formed are formed on the side, and this state is maintained and the hot pressing 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 gas vent space 12g and stays in a gas state, and a part thereof is a gap between each through hole 12e of the upper mold 12 and the rod portion 13b. It flows out of the system through.
[0027]
By completing the fourth step, the fiber mat 20 is formed into a fiber board having a shape corresponding to the mold surfaces of both the molds 11 and 12. When the fourth step is finished, the upper mold 12 is raised to the top dead center. As a result, the upper die 12 is retracted from the lower die 11, and the punch 13 is separated from the piston rod 15b of each hydraulic cylinder 15. The punch 13 is moved by the action of each compression spring 14 so that the holder portion 13a contacts the upper surface of the molding pad 12b. Returning to the contact state, the molding apparatus 10 returns to the state shown in the first step of FIG.
[0028]
Thus, according to the molding method employing the fiber board molding apparatus 10 according to the present invention, the gaseous solvent that volatilizes during the molding of the fiber mat 20 stays in the gas vent space 12g and stays there. Since the gaseous solvent is discharged out of the system, the penetration of the gaseous solvent into the interior of the fiber mat 20 during the molding is prevented or greatly suppressed, so that molding defects do not occur and good quality is achieved. Fiberboard can be provided. Further, when the fiber mat 20 is molded, the molding can be completed in a state where both the molds 11 and 12 are sufficiently clamped, so that the time required for molding the fiber mat 20 can be greatly shortened.
[0029]
FIG. 5 shows another example of the fiberboard molding apparatus according to the present invention. The molding apparatus 10a is provided with suction means in the molding apparatus 10 described above, and a suction pump 17 is employed as the suction means. The suction pump 17 is connected to the recess 12c of the mold main body 12a of the upper mold 12, and by driving the suction pump 17, gas that volatilizes during the molding of the fiber mat 20 and stays in the gas vent space 12g. The solvent can be sucked through the recess 12c of the mold body 12a of the upper mold 12 and forcibly discharged out of the system. In this state, the gaseous solvent can be recovered efficiently.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an operating 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 operating state in a fourth step of a molding apparatus according to another example of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10,10a ... Molding apparatus, 11 ... Lower mold, 11a ... Mold body, 11b ... Mold surface, 12 ... Upper mold, 12a ... Mold body, 12b ... Mold pad, 12c ... Recess, 12d ... Mold surface, 12e ... Through Hole, 12f ... Insertion hole, 12g ... Gas vent space, 13 ... Punch, 13a ... Holder part, 13b ... Rod part, 14 ... Compression spring, 15 ... Hydraulic cylinder, 15a ... Cylinder part, 15b ... Piston rod, 16 ... Control unit, 17 ... suction pump, 20 ... fiber mat, 21, 22 ... fiber web, 23 ... binder solution.

Claims (8)

A fiber board molding apparatus for sandwiching a fiber mat impregnated with a binder solution between both molds and hot pressing to form a fiber board, the molding apparatus having a mold surface on the upper surface side. A mold, an upper mold having a mold surface on the lower surface side, and advancing and retracting relative to the lower mold, and a plurality of through holes provided through the mold surface of the upper mold so as to be movable back and forth. A punching means for forming a degassing space portion in which the volatilized solvent stays at the front end portion of the through hole at a retracted position retracted from the mold surface side of the mold, and the punching means to the mold surface side of the upper mold Spring means for energizing and moving to the forward position and pressing means provided on the lower mold so as to oppose the punching means to receive the punching means and advance and retract the punching means during operation. An apparatus for forming a fiber board, characterized by comprising: The molding apparatus according to claim 1, wherein the molding apparatus includes suction means for sucking and discharging a solvent that volatilizes and stays in a gas vent space formed in each through hole of the upper mold. An apparatus for forming a fiber board, characterized by comprising: 2. The forming apparatus according to claim 1, wherein the punching means is a punch that advances and retracts each through hole of the upper die, and the pressing means is a fluid pressure cylinder. A molding method for molding a fiber mat into a fiber board using the molding apparatus according to claim 1, wherein the upper die is advanced relative to the lower die, and the punching means is moved to the pusher. A first step of positioning the fiber mat in a state where it is received by the moving means and impregnated with the binder solution between the two molds, and the upper mold is further advanced relative to the lower mold to push the pusher. A second step of moving the upper die to the bottom dead center by operating a moving means; and a third step of hot pressing the fiber mat for a predetermined time in a state where the upper die is moved to the bottom dead center; When the fiber mat is hot-pressed for a predetermined time, the pushing means is operated to retract the punching means to form a gas vent space on the mold surface side of each through hole of the upper mold. A method for forming a fiber board, comprising: 5. The molding method according to claim 4, wherein the fibers constituting the fiber mat are cellulosic natural fibers. 5. The molding method according to claim 4, wherein the fibers constituting the fiber mat are cellulosic chemical fibers. 5. The molding method according to claim 4, wherein the binder solution impregnated in the fiber mat is a volatile solvent solution. The molding method according to claim 7, wherein the binder solution is a volatile solvent solution obtained by dissolving acetate in acetone.

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