JP2014188835A - Foamed resin material filling machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the designability of a molded product at a position facing a foamed resin material filling machine and in the vicinity of the position, in the foamed resin material filling machine.SOLUTION: A foamed resin material filling machine includes a cylindrical pipe 52 which is formed with a passage 53 for supplying a foamed resin material, and a plunger 70 which is slidably disposed in the passage 53 and controls the supply of the foamed resin material by closing a tip of the passage 53. The pipe 52 is mounted so that the tip of the passage 53 faces outside toward a cavity 22 of a foamed resin molding die. The outer periphery of the pipe 52 is formed with one or a plurality of slits 58, communicating the cavity 22 of the foamed resin molding die with an outer space, along the direction of the passage 53. The one or the plurality of slits 58 do not reach the passage 53 of the pipe 52.

Description

  The present invention relates to a foamed resin raw material filling machine for filling pre-expanded particles in a cavity of a foamed resin molding die.

  A foamed resin raw material filling machine (hereinafter simply referred to as “filling machine” as necessary) is used for filling the pre-foamed particles into the mold cavity used for foamed resin molding. This type of filling machine includes a cylindrical pipe having a flow path for supplying pre-expanded particles and a plunger that is slidably disposed in the pipe so that the tip of the pipe projects into the cavity. Used by attaching to a mold.

  The filling machine opens the flow path by retracting the plunger, fills the pre-expanded particles into the cavity from the flow path with compressed air, and advances the plunger to the tip of the pipe to close the flow path. Then, the supply of the pre-expanded particles is stopped.

  The mold has a steam chamber that supplies steam or cold air (sometimes hot water or cold water) to the cavity around the mold, and steam enters the cavity through the steam holes formed in the mold. By continuously supplying cold air, the pre-expanded particles are expanded (re-expanded) and fused together to form a foamed resin molded product.

  On the other hand, steam or cold does not circulate well at the position facing the filling machine, and there is a risk of causing poor fusion at the contact mark that has been in contact with the filling machine in the molded product. Therefore, in Patent Document 1, a plurality of radial slits are formed in the radial direction so as to straddle the flow path at the tip of the pipe, and steam or the like is introduced from the slit by communicating the cavity and the steam chamber with the slit. In addition, it is intended to prevent poor fusion of the foamed resin molded product at the position opposite to the filling machine and in the vicinity thereof.

JP 2011-104784 A

  However, part of the pre-foamed particles or foamed foamed resin may be caught in the slit while molding is repeated. In particular, the foamed material bitten between the plunger and the slit will cause the foamed material bitten at the time of mold release to scrape off or peel off the surface of the molded product, so that the design of the molded product will deteriorate. Further, in the subsequent molding process, molding is performed with the remaining foam material adhering to the plunger surface, so that unintended irregularities are formed on the molded product, or the remaining foam material is between the flow path. The plunger may become clogged, resulting in insufficient advancement of the plunger.

  Furthermore, since the slit is opened through the pipe in the radial direction, when pre-expanded particles are filled into the cavity, compressed air leaks from the middle of the flow path into the cavity and vapor chamber, stabilizing the pre-expanded particles. Supplyability may be reduced or filling may be poor.

  The objective of this invention is providing the foaming resin raw material filling machine which can improve the designability of a molded article.

In order to solve the above problems, the foamed resin material filling machine of the present invention is
A cylindrical pipe in which a flow path for supplying a foamed resin raw material is formed;
A plunger that is slidably disposed in the flow path, and that controls the supply of the foamed resin raw material by closing the tip of the flow path;
With
The pipe is a foamed resin raw material filling machine attached so that the end of the flow path protrudes toward the cavity of the foamed resin mold,
On the outer periphery of the pipe, one or a plurality of slits communicating the cavity of the foamed resin molding die and the external space are recessed along the flow path direction,
The one or more slits do not reach the flow path of the pipe.

  According to the foamed resin raw material filling machine of the present invention, the pipe is formed with one or more slits at the end on the mold side, and the mold cavity communicates with an external space such as a steam chamber. Therefore, the filling machine is heated or cooled by steam or cold air from the external space, and the foamed resin at the opposite position of the filling machine and in the vicinity thereof is also heated or cooled in the same manner as other parts. Therefore, in the molded product, the fusion property at the contact mark with the filling machine can be improved.

  Further, since the slit does not reach the flow path of the pipe, it is possible to prevent the foamed resin from being caught between the slit and the flow path. As a result, it is possible to prevent the surface of the molded product from being damaged or peeled off at the time of mold release.

  Therefore, it is possible to improve the design of the surface of the molded product at the opposite position (contact trace) of the filling machine and in the vicinity thereof, and to suppress insufficient strength.

  In addition, since the biting of the foamed resin is suppressed, maintenance work such as cleaning around the plunger can be reduced.

  Furthermore, since the compressed air at the time of filling the foamed resin raw material does not leak from the flow path to the slit, the foamed resin raw material can be stably supplied, and poor filling of the cavity can be avoided.

FIG. 1 is a cross-sectional view of a molding apparatus including a foamed resin material filling machine according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the filling machine. 3A is an enlarged view of the pipe tip, and FIG. 3B is a cross-sectional view taken along the flow path of the pipe tip. FIG. 4 is an enlarged view of the contact mark with the filling machine and the vicinity thereof in a molded product molded by the foamed resin material filling machine of the present invention. FIG. 5 is an enlarged view of the front end of the filling machine showing a different embodiment of the foamed resin material filling machine of the present invention, in which a groove is formed in the plunger. FIG. 6 is an enlarged view of the front end of the filling machine showing still another embodiment of the foamed resin material filling machine of the present invention, and is a view in which a groove different from FIG. 5 is formed in the plunger.

  The present invention relates to a foamed resin raw material filling machine (50) that is attached to a foamed resin molding die (20) used for molding of a foamed resin molded product and fills pre-expanded particles, and more specifically. As shown in FIGS. 2 and 3, which will be described later, one or more slits (58) that do not reach the flow path (53) are formed at the outer peripheral tip of the pipe (52) that becomes the flow path (53) of the pre-foamed particles. ) In the longitudinal direction, the foamed resin material filling machine (50).

  Hereinafter, the overall configuration of the molding apparatus (10) will be described first, and then the filling machine (50) will be described.

  FIG. 1 is a longitudinal sectional view of a molding apparatus (10) including a foamed resin material filling machine (50) according to an embodiment of the present invention. The molding apparatus (10) fills the pre-expanded particles (foamed resin raw material) from the filling machine (50) into the cavity (22) formed between the fixed mold (30) and the movable mold (40), By heating the inside of the cavity (22), the pre-expanded particles are expanded (re-expanded) and further fused to each other to form a molded product.

  The fixed mold (30) and the movable mold (40) each have an external space formed by the back plates (32) and (42) on the back side, and this external space is vaporized via a pipe line (not shown). The steam chambers (34) and (44) are supplied with cold air. The stationary mold (30) and the movable mold (40) are formed with a plurality of vapor holes (not shown) through which vapor or cold air is passed from the vapor chambers (34) (44) through the cavity (22 ).

  One or more ejection pins (12) for release are attached to the fixed mold (30). The eject pin (12) faces the cavity (22), enters the cavity (22) and pushes out the molded product, and a rod with a head part (13) provided at the tip With part (14). The rod part (14) is connected to an actuator (not shown), and by moving the rod part (14) forward, the head part (13) enters the cavity (22) and the molded product after molding is released. Then, by retracting the rod part (14), the head part (13) is pulled back to the fixed mold (30) side.

  The movable mold (40) is configured to be able to approach and separate from the fixed mold (30) by the cylinder (46). The movable mold (40) moves closer to the fixed mold (30) when the mold is clamped, and moves away from the mold when dividing the mold.

  The supply of the pre-expanded particles to the cavity (22) formed by the fixed mold (30) and the movable mold (40) is performed by a filling machine (50) attached to the fixed mold (30). As shown in FIG. 1, the filling machine (50) is arranged such that the pipe (52) through which the pre-expanded particles flow is exposed from the stationary mold (30) to the cavity (22).

  FIG. 2 is a sectional view of the filling machine (50). As shown in the figure, the filling machine (50) includes a cylindrical pipe (52) in which a flow path (53) in which pre-expanded particles flow is formed in the cavity (22), and a flow path (53). A plunger (70) that is slidably disposed and controls the supply of the pre-expanded particles by closing the tip of the channel (53).

  More specifically, the pipe (52) is provided at the end of the straight pipe portion (54) and the straight pipe portion (54) arranged so as to protrude from the back plate (32) to the fixed mold (30). A branch pipe (56) that is bent and extends from the branch section (55) and is connected to a supply source of pre-expanded particles (not shown).

  The straight pipe portion (54) can have a double cylinder structure of an inner cylinder (60) and an outer cylinder (62). The inner cylinder (60) serves as a flow path (53) for pre-expanded particles, and the inner cylinder The space formed between the (60) and the outer cylinder (62) is connected to a pump (not shown) for supplying compressed air via the air port (63), and the compressed air is connected to the tip of the pipe (52). It is a passage that discharges towards

  As shown in FIG. 3, the inner cylinder (60) has a shorter tip than the outer cylinder (62). On the other hand, the outer cylinder (62) has the outer diameter as it is, and the nozzle (64) tapering until it becomes the same as the inner diameter of the inner cylinder (60) on the front side of the tip of the inner cylinder (60), And a thick part (65) at the tip. With this structure, it is possible to prevent overfilling of the supplied pre-expanded particles.

  3 (a) is a view of the filling machine (50) as viewed from the front end side of the pipe (52), and FIG. 3 (b) is a sectional view of the flow path (53) at the front end of the pipe (52). . As shown in FIGS. 3 (a) and 3 (b), the thick part (65) of the pipe (52) is provided with one or more slits (58) along the longitudinal direction. The slit (58) is formed so as to communicate the cavity (22) and the vapor chamber (34) through the fixed mold (30) but does not reach the flow path (53). The illustrated slit (58) has a shape that becomes shallower from the cavity (22) side toward the steam chamber (34) while leaving an inner wall (59) that does not reach the flow path (53).

  In FIG. 3, eight slits (58) are formed at equal intervals in the circumferential direction, that is, every 45 degrees. The number of slits (58) is not limited to this.

  The width of the slit (58) is formed smaller than the diameter of the pre-expanded particles. Thereby, the outflow of the pre-expanded particles from the slit (58) to the vapor chamber (34) can be prevented. The width of the slit (58) is preferably 0.8 times or less of the diameter of the pre-expanded particles, and more preferably 0.6 times or less of the diameter of the pre-expanded particles.

  The plunger (70) is slidably disposed on the straight pipe portion (54). The plunger (70) is connected to the actuator (72), and the rod part (73) of the actuator (72) is projected and retracted from the cylinder (74), so that the straight pipe part (54) It moves while being in sliding contact with the inner cylinder (60) in the vicinity of the tip of the pipe, and is in sliding contact with the inner surface of the thick part (65) of the reduced diameter outer cylinder (62) at the tip of the straight pipe part (54). . An O-ring (71) for sealing is fitted on the peripheral surface of the plunger (70).

  However, in the foamed resin molding apparatus (10) including the filling machine (50) having the above-described configuration, the cylinder (46) is extended to move the movable mold (40) closer to the fixed mold (30), and the fixed mold A cavity (22) is formed between (30) and the movable mold (40).

  In this state, the actuator (72) is operated to retract the plunger (70) to the branching portion (55) to supply the pre-foamed particles inside the inner cylinder (60), and from the air port (63). Compressed air is supplied between the cylinder (60) and the outer cylinder (62).

  Thereby, filling of the pre-expanded particles into the cavity (22) is started.

  At this time, since the slit (58) is not in communication with the flow path (53), it is possible to prevent the compressed air from leaking from the slit (58) to the cavity (22) or the steam chamber (34). For this reason, stable supply of pre-expanded particles and insufficient filling can be prevented, and nests (pores) can be prevented from occurring in the molded product.

  When the filling of the pre-expanded particles is completed, the actuator (72) is operated to move the plunger (70) to the tip of the pipe (52). Thereby, the flow path (53) is closed and the supply of the pre-expanded particles is stopped. Further, the O-ring (71) of the plunger (70) contacts the tip of the outer cylinder (62), so that the flow path (53) is hermetically blocked from the cavity (22).

  In this state, steam is supplied to the steam chambers (34) and (44), which are external spaces, and the inside of the cavity (22) is heated. At this time, since the slit (58) communicates the steam chamber (34) and the cavity (22), the steam in the direction of arrow F in FIG. The pipe (52) and the tip of the plunger (70) are heated, and the opposite positions and the vicinity thereof are heated in the same manner as the other parts, and the desired foaming (re-expansion) of the pre-foamed particles is performed. Expansion) and can be fused to each other.

  Subsequently, cool air is supplied to the steam chambers (34) and (44) to cool the inside of the cavity (22). At this time, since the slit (58) communicates the steam chamber (34) and the cavity (22), cold air is supplied in the direction of arrow F in FIG. 3 (b), and the pipe (52) and the plunger ( While the tip of 70) is cooled, these opposed positions and the vicinity thereof can be cooled in the same manner as other portions, and a molded product is formed.

  When the molding of the molded product is completed, the cylinder (46) is contracted to move the movable mold (40) away from the fixed mold (30). Further, the actuator may be operated to cause the eject pin (12) to protrude toward the cavity (22), thereby releasing the molded product from the fixed mold (30).

  According to the present invention, the tip of the filling machine (50) can be heated or cooled in the same manner as the stationary mold (30). Thereby, in the molded product, it is possible to improve the fusion property at the contact mark where the filling machine (50), specifically, the opposed position of the pipe (52) and the plunger (70) and the vicinity thereof are in contact. .

  As a result, it is possible to improve the design of the surface of the molded product at the contact mark of the filling machine (50), and it is possible to suppress insufficient strength of the molded product.

  Furthermore, the slit (58) is formed to a depth that does not reach the flow path (53) of the pipe (52). Therefore, with the plunger (70) moving forward and blocking the flow path (53), the peripheral surface of the plunger (70) is not in direct contact with the slit (58), and the plunger (70) and slit Since the inner wall (59) is interposed between the (58) and the pre-foamed particles and foamed foam resin between the plunger (70) and the slit (58), they are prevented from biting and adhering. it can.

  As a result, it is possible to prevent the surface of the molded product from being scratched or peeled off during mold release. Further, since it is possible to prevent the pre-expanded particles and the like from being caught between the plunger (70) and the pipe (52), the sliding of the plunger (70) by these biting is not hindered. 70) can prevent advancement of the pre-foamed particles or the like into the flow path (53) at the time of insufficient advancement or backward movement, and can reduce the maintenance work of the filling machine (50).

  FIG. 4 is an enlarged view of the contact mark of the molded product (90) produced as described above by the filling machine (50) and the vicinity thereof. As shown in the figure, the molded product (90) molded using the filling machine (50) of the present invention has a molding mark (58) formed by a slit (58) that does not reach the inner periphery in the region facing the pipe (52). 92) is formed in a convex shape, and the gap between the pipe (52) and the plunger (70) is formed in a convex shape as an annular molding mark (94). It can be seen that the molding mark (92) due to the slit (58) does not reach the position facing the plunger (70) and does not intersect the annular molding mark (94).

  In addition, the produced molded product (90) is not damaged or peeled off due to biting of pre-expanded particles or foamed resin at or near the contact mark by the filling machine (50), and the design property is improved. You can see that

  Note that one or more grooves (76) can be formed at the tip of the plunger (70) as shown in FIGS. In the example of FIG. 5, eight grooves (76) are formed radially from the center of the plunger (70) at equal intervals in the circumferential direction, and the slits (58) and at least the ends of the grooves (76) are formed. Are formed so as to face each other across the inner peripheral surface of the tip of the pipe (52). In the example of FIG. 6, a plurality of parallel grooves (76) are formed.

  By forming such a groove (76), it is possible to easily spread steam and cold air from the peripheral portion of the plunger (70) to the inner side, and in the contact mark on the filling machine (50) and in the vicinity thereof. It is possible to further suppress poor fusion of the surface of the molded product, and to suppress overexpansion of the molded product due to heat storage of the plunger (70).

  The above description of the embodiments is for explaining the present invention, and should not be construed as limiting the invention described in the claims or reducing the scope thereof. In addition, the configuration of each part of the present invention is not limited to the above embodiment, and various modifications can be made within the technical scope described in the claims.

  For example, the slit (58) communicates with the cavity (22) and the steam chamber (34) serving as the outer peripheral space thereof, but has a concave groove shape as described above as long as it does not communicate with the flow path (53). It is not limited to a thing, It can also be set as a through-hole.

  Of course, the configuration and shape of the filling machine (50) and the configuration and shape of the mold (20) are not limited to the above embodiment.

(10) Molding equipment
(20) Foamed resin mold
(22) Cavity
(30) Fixed type
(34) Steam room (external space)
(50) Foaming resin material filling machine
(52) Pipe
(58) Slit
(70) Plunger

Claims (5)

A cylindrical pipe in which a flow path for supplying a foamed resin raw material is formed;
A plunger that is slidably disposed in the flow path, and that controls the supply of the foamed resin raw material by closing the tip of the flow path;
With
The pipe is a foamed resin raw material filling machine attached so that the end of the flow path protrudes toward the cavity of the foamed resin mold,
On the outer periphery of the pipe, one or a plurality of slits communicating the cavity of the foamed resin molding die and the external space are recessed along the flow path direction,
The foamed resin material filling machine, wherein the one or more slits do not reach the flow path of the pipe.   The foaming resin raw material filling machine according to claim 1, wherein a groove extending from an outer peripheral edge portion toward a center portion side is formed on a front end surface of the plunger.   The foaming resin raw material filling machine according to claim 2, wherein at least a part of the groove is opposed to the slit across the inner peripheral surface of the tip of the pipe.   A foamed resin molding die, wherein the foamed resin raw material filling machine according to any one of claims 1 to 3 is disposed so that a tip of the pipe projects into a cavity of the die.   5. A molded product molded by the foamed resin molding die according to claim 4, wherein one or a plurality of molding marks are projected at a position facing the slit at a facing position of the foamed resin raw material filling machine. The molded mark does not reach the position facing the plunger.

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