JP5079254B2 - Molding device for hollow resin molding - Google Patents

Description

  The present invention relates to a molding apparatus for molding a resin hollow molded body.

  Conventionally, a sheet material made of a thermosetting resin is wound around the outer surface of an expandable core so as to form a hollow portion, and a pressure fluid is introduced into the hollow portion in a state where the sheet material is disposed in a mold, and is pressurized and expanded. Thus, a molding apparatus is known that presses the sheet material against the molding surface of a molding die to mold a resin hollow molded body.

For example, in Patent Document 1, a thermosetting resin sheet is formed by molding a thermosetting resin sheet by introducing a pressure fluid into the inside of the mold and inserting the pressure fluid in a state where the thermosetting resin sheet is wound around the outer periphery and inserted into the mold. A pressure bag for internal pressure molding is disclosed in which molding is performed by pressing and intimate contact with the inner surface of the inner pressure. In this pressure bag, the film thickness of the corresponding inflection part corresponding to the inflection point after molding and hardening of the thermosetting resin sheet wound around the outer periphery is made thinner than the surrounding film thickness.
Japanese Patent No. 3359789

  By the way, gas and liquid can be considered as the pressure fluid, but if it is gas, it is easily affected by temperature and the like, and is easily compressed. On the other hand, liquid is less affected by temperature and difficult to be compressed. .

  In the above conventional molding apparatus for hollow molded bodies, only one introduction pipe for sending pressure fluid into the pressure bag (core) is provided, and another pipe for discharging the pressure fluid in the pressure bag is provided. It is not done.

  When a liquid is used as a pressure fluid in a conventional molding apparatus for a hollow molded body, when the liquid is fed from the introduction pipe into the pressure back for molding, there is only one introduction pipe. It cannot be discharged. For this reason, the pressure bag cannot be filled with liquid, air is mixed in the pressure bag, the internal pressure in the pressure bag is insufficient, and the desired hollow molded body can be molded by the resin sheet. There was a problem of disappearing.

  In addition, when the liquid in the pressure bag is discharged after molding, there is only one introduction pipe, so that the liquid cannot be sufficiently discharged, and a negative pressure is applied to the introduction pipe to discharge the pressure fluid. In this case, the hollow molded body is also undesirably deformed due to dents or the like.

  This invention is made | formed in view of this point, The place made into the objective is to enable it to perform supply and discharge | emission and discharge | emission of the air and the liquid in the hollow part of a core efficiently.

To achieve the above object, according to the present invention, the opening of the core, air pipe and the liquid air flows were to tip a liquid pipe flowing inserts respectively to extraordinary useless hollow portion.

Specifically, in the first invention, a pressure fluid is placed inside the core in a state in which a resin sheet is wound around the outer surface of the core that can be expanded so as to form a hollow portion and disposed in the mold. Intended for a molding apparatus for molding a resin hollow molding by pressing the sheet material against the molding surface of the molding die by introducing
The core has one opening communicating with the hollow portion, extraordinary to the opening portion, a distal end and a liquid pipe the hollow portion of the liquid flows as the air pipe and the pressure fluid air flows Are set so that the air pipe tip is positioned above the liquid pipe tip ,
During the pressure molding of the sheet material, the pressurized liquid is fed into the hollow part from the liquid pipe to increase the pressure in the hollow part, and the air in the hollow part is discharged from the air pipe. When the mold is removed, a control device is provided that feeds the air from the air pipe into the hollow portion and discharges the liquid in the hollow portion from the liquid pipe.

In the second invention, the extension length of the air pipe from the opening into the hollow portion is set longer than the extension length of the liquid pipe .

According to the above Symbol first invention, when press molding of the sheet material, than the air pipe tip of the hollow portion when discharging air in the hollow portion from the air pipe pressurized liquid is fed into the hollow portion from the liquid pipe Liquid is filled from the tip of the liquid pipe disposed on the lower side, and air can be efficiently discharged from the tip of the air pipe disposed on the upper side. Accordingly, the sheet material can be pressed against the molding surface of the molding die at a high pressure with a liquid in which air is not mixed via the core, and the intended resin hollow molded body can be molded with high accuracy. Conversely, when removing the hollow molded body, air is fed into the hollow portion from the air pipe tip on the upper side of the hollow portion, and the liquid accumulated on the lower side is efficiently discharged from the liquid pipe tip on the lower side of the air pipe tip. can do. As a result, the hollow molded body with a smaller amount of liquid remaining in the core can be removed , and the time required to discharge the residual liquid from the molded body after demolding can be further reduced. Therefore, the supply and discharge of air and liquid in the hollow portion can be performed more efficiently, and the intended resin hollow molded body can be molded more efficiently.

According to the second aspect of the present invention, when the sheet material is pressed by the operation of the control device, the pressurized liquid is fed into the entire hollow portion from the tip of the liquid pipe shorter than the air pipe, and the pressure in the hollow portion is adjusted. While increasing, the air in a hollow part can be discharged | emitted from the air pipe front-end | tip away from the liquid pipe front-end | tip. Thereby, a sheet | seat material can fully be pressed to the molding surface of a shaping | molding die via a core, and the resin hollow molded object of the target shape can be shape | molded. When removing the hollow molded body, the air in the hollow part can be discharged from the tip of the liquid pipe close to the opening by sending air from the tip of the air pipe into the hollow part from the back side of the hollow part. As a result, the resin hollow molded body with little residual liquid in the core can be removed, and the time required to discharge the residual liquid from the molded body after demolding can be reduced. Therefore, the supply and discharge of air and liquid in the hollow portion can be performed efficiently, whereby the intended resin molded body can be efficiently molded.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows an enlarged part of a molding die 1 in a molding apparatus 10 for a resin hollow molded body according to an embodiment of the present invention. FIG. 2 is a plan view of the introduction nozzle 11. FIG. 3 shows a molding apparatus 10 for a resin hollow molded body.

  As shown in FIG. 1, the mold 1 includes an upper mold 3 and a lower mold 5, and a container-shaped resin hollow molded body 7 is molded between the upper mold 3 and the lower mold 5. The cavity 9 is formed. As shown in FIG. 5, the hollow molded body 7 is made of a thermosetting resin such as a phenol resin (PF), an epoxy resin (EP), or a melamine resin (MF). In this embodiment, a rectangular bottom portion 7a, The rectangular cylindrical side portion 7b, a tapered portion 7c that narrows toward the tip, and a bottomed rectangular cylindrical shape provided with a molded body opening 7d in the tapered portion 7c.

  The upper mold 3 is formed with a first molding surface 3a for forming one outer surface when the hollow molded body 7 is cut by a plane extending in the longitudinal direction through the center line. Is formed with a second molding surface 5 a for forming the other outer surface of the hollow molded body 7. The cavity 9 formed by the first and second molding surfaces 3a and 5a communicates with the outside of the molding die 1, and the introduction nozzle 11 is inserted into a portion communicating with the outside.

  As shown in FIG. 2, the introduction nozzle 11 includes a columnar nozzle body 13, a nozzle side flange 15 formed in a convex shape on the longitudinal outer peripheral portion of the nozzle body 13, and the length of the nozzle body 13. An air pipe insertion hole 17 and a liquid pipe insertion hole 19 through which the air pipe 21 penetrating in the direction and the air pipe 21 through which the air flows and the liquid pipe 23 through which the liquid as the pressure fluid flows are respectively formed are formed.

  The liquid pipe 23 protrudes horizontally from the nozzle body 13 and is shorter than the air pipe 21. The air pipe 21 projects horizontally from the nozzle body 13 to a position corresponding to the tip 23a of the liquid pipe 23, and is bent so as to gradually approach the first molding surface 3a of the upper mold 3 from the liquid pipe tip 23a upward. The tip 21a is positioned above the liquid pipe tip 23a. As shown in FIGS. 1 and 2, the extension length L1 of the air pipe 21 from the opening 27c into the hollow portion 25 is set to be longer than the extension length L2 of the liquid pipe 23 (L1> L2). . That is, the extension length L1 of the air pipe 21 into the hollow portion 25 protrudes longer than the extension length L2 of the liquid pipe 23.

  An inflatable core 27 made of, for example, polyethylene terephthalate (PET) resin having a hollow portion 25 is attached to the tip side (hollow portion 25 side) of the nozzle body 13 from the nozzle side flange 15. The core 27 includes a large-diameter portion 27a having a hollow portion 25, a small-diameter portion 27b having one opening portion 27c communicating with the hollow portion 25, and a tapered portion between the large-diameter portion 27a and the small-diameter portion 27b. 27e is integrally formed, and the large-diameter portion 27a and the bottom wall portion 27d are integrally formed with the large-diameter portion square shape and the small-diameter portion circular shape. The hollow body 25 side of the nozzle body 13 is pushed into the small diameter part 27b. A convex core side flange 27f is formed in the vicinity of the opening 27c, and an inner O-ring 31 is fitted into the small diameter portion 27b so as to contact the core side flange 27f. On the proximal end side of the nozzle side flange 15 of the nozzle body 13, an outer O-ring 33 is fitted so as to contact the nozzle side flange 15. The inner O-ring 31 and the outer O-ring 33 are pressed by the first small-diameter inner surface 3b of the upper mold 3 and the second small-diameter inner surface 5b of the lower mold 5 when the mold 1 is closed. The liquid and air in the inside 27 (in the hollow portion 25) are prevented from leaking out of the core 27. That is, the inner O-ring 31 prevents liquid or air from leaking between the large-diameter portion 27a of the core 27 and the first molding surface 3a and the second molding surface 5a. Further, air and air are prevented from leaking out of the mold from the base end side (left side in FIG. 1) of the nozzle body 13.

  A sheet material 35 made of a thermosetting resin, which is a material of the hollow molded body 7, is wound around the outer surface of the core 27. The sheet material 35 includes, for example, a bottom portion 35a corresponding to the bottom wall portion 27d of the core 27, a side portion 35b corresponding to the large diameter portion 27a of the core 27, and the core 27 as shown in a development view shown in FIG. The shape of the distal end portion 35c corresponding to the tapered portion 27e is configured by a rectangle or a trapezoid so as to be easily cut and wound. The sheet material 35 may be a sheet in which a reinforcing fiber such as carbon fiber or glass fiber is mixed with a thermosetting resin, or a sheet formed by laminating a reinforcing fiber sheet on a sheet of a thermosetting resin alone.

  The resin hollow molded body molding apparatus 10 includes a control device 43. In a state where the sheet material 35 is wound around the outer surface of the core 27 and disposed in the mold 1, mechanical oil as a liquid (pressure fluid) is introduced into the core 27 and pressurized under the control of the control device 43. By expanding, the sheet material 35 is pressed against the first and second molding surfaces 3a and 5a of the mold 1 to mold the resin hollow molded body 7. The small diameter portion 27b of the core 27 is cut after demolding.

-Operation-
Next, the operation of the hydraulic circuit of the molding apparatus 10 for the hollow molded body 7 according to the present embodiment will be described in detail with reference to FIG.

(1) Preparation of Core 27 and Sheet Material 35 First, the inner O-ring 31 was fitted into the small diameter portion 27b of the core 27 so as to contact the core side flange portion 27f, and the air pipe 21 and the liquid pipe 23 were attached. The nozzle body 13 is inserted into the small diameter portion 27 b while inserting the pipes 21 and 23 into the hollow portion 25 from the opening portion 27 c of the core 27. This insertion amount is inserted until the tip of the small diameter portion 27b comes into contact with the nozzle side flange portion 15. Thereafter, the outer O-ring 33 is fitted into the nozzle body 13 so as to contact the nozzle side flange 15. The outer O-ring 33 may be inserted into the nozzle body 13 in advance before the nozzle body 13 is inserted into the small diameter portion 27b of the core.

  Next, the sheet material 35 is wound around the outer periphery of the core 27.

  The air pipe 21 of the introduction nozzle 11 is connected to the circuit K1, and the liquid pipe 23 is connected to the circuit K2.

  Next, the core 27 around which the sheet material 35 is wound is disposed on the lower mold 5 of the mold 1 so as to be substantially horizontal, and the upper mold 3 and the lower mold 5 are closed.

(2) Pressurization operation in the hollow portion 25 of the core 27 The oil tank 41 stores machine oil, and the oil tank 4 includes an air opening (not shown). When a signal is sent from the control device 43 to the electric motor 45 and the electric motor 45 is driven, the hydraulic oil is pressurized by the hydraulic pump 47.

  The pressurized machine oil passes through the check valve 49 and flows to the four-port three-position switching valve 51.

  A relief valve 53 is provided in front of the four-port three-position switching valve 51 and is relieved to the oil tank 41 at a predetermined pressure or higher.

  A signal is sent from the control device 43 to the solenoid b of the four-port three-position switching valve 51, the spool moves to the left, and the pressurized machine oil reaches the throttle valve 55 with a check valve through the B port.

  Subsequently, the flow rate is adjusted by the throttle valve 55 with a check valve. The machine oil whose flow rate has been adjusted reaches the first solenoid valve 57.

  In the first solenoid valve 57, machine oil flows from the circuit K2 into the mold 1 through the A port.

  In the mold 1, machine oil is introduced from the liquid pipe 23 into the hollow portion 25 of the core 27. At this time, the pressurized machine oil is fed from the liquid pipe tip 23a shorter than the air pipe 21 into the entire hollow portion 25, the pressure in the hollow portion 25 is increased, the core 27 is pressurized and expanded, and the sheet The material 35 is pressed against the first and second molding surfaces 3a and 5a. At this time, the air in the hollow portion 25 passes through the air pipe 21, the circuit K 1 and the A port of the second solenoid valve 59 and the A port of the third solenoid valve 61 through the air pipe 21 and the circuit K 1. It flows out to the tank 41. At this time, since the liquid is filled from the liquid pipe tip 23a disposed below the air pipe tip 21a in the hollow portion 25 and the air is discharged from the air pipe tip 21a disposed above, the air is efficiently discharged. The

  Next, the air remaining in the hollow portion 25 is discharged together with the machine oil to the oil tank 41 through the same path as the air discharge path.

  When the air in the hollow portion 25 is sufficiently discharged, that is, when a set time elapses after a signal is sent to the solenoid b of the four-port three-position switching valve 51, a signal is sent from the control device 43 to the second solenoid valve 59. , The spool moves to the left, the circuit K1 is shut off, the discharge of the machine oil from the mold 1 stops, and the inside of the hollow portion 25 is kept at a constant pressure. The machine oil from the hydraulic pump 47 is relieved from the relief valve 53. By maintaining the hollow portion 25 at a constant pressure, the sheet material 35 is pressed for a predetermined time while being pressed against the first and second molding surfaces 3a and 5a at a predetermined temperature, and the hollow molded body 7 is molded. . Since no air remains in the hollow portion 25, the sheet material 35 can be pressed at a high pressure with a liquid in which air does not enter the first and second molding surfaces 3a, 5a of the mold 1 via the core 27, The resin hollow molded body 7 having a desired shape can be molded. For example, the mold 1 is heated to about 110 to 150 ° C., and the machine oil is heated to about 100 to 110 ° C.

(3) Depressurization operation in the hollow portion 25 of the core 27 Next, a demolding operation after molding will be described.

  As described above, when a hollow molded body is formed from the sheet material 35, that is, when a set time elapses after the cutoff signal of the circuit K1 is sent to the second solenoid valve 59, a signal is sent from the control device 43 to the electric motor 45. Is stopped, and the drive of the electric motor 45 is stopped.

  Next, a signal is sent from the control device 43 to the first solenoid valve 57, the spool moves to the left, and the circuit K2 communicates with the B port and communicates with the oil tank 41. In synchronization with this, a signal is sent to the second solenoid valve 59, the spool moves to the right, the circuit K1 communicates with the A port, a signal is sent to the third solenoid valve 61, and the spool moves to the left. The circuit K1 communicates with the B port via the second solenoid valve 59.

  Next, air is supplied from the air supply port 63, and the air is sent into the hollow portion 25 from the air pipe 21 through the B port of the third solenoid valve 61, the A port of the second solenoid valve 59 and the circuit K 1. That is, air is fed into the hollow portion 25 from the air pipe tip 21a located above the hollow portion 25, whereby the machine oil in the hollow portion 25 is discharged from the liquid pipe tip 23a. At this time, most of the machine oil collected below the liquid pipe tip 23a is discharged from the liquid pipe 23 by high-pressure air. The machine oil that has flowed out of the mold 1 from the liquid pipe 23 passes through the circuit K 2 and the B port of the first solenoid valve 57 and is discharged to the oil tank 41.

  When the machine oil in the hollow portion 25 is sufficiently discharged, a signal is sent from the control device 43 to the third solenoid valve 61, the spool moves to the right, and the A port communicates. Thereby, supply of air stops, air flows into the oil tank 41 side, and the pressure in the hollow part 25 falls. As described above, since the liquid is not discharged by applying a negative pressure to the core 27, the hollow molded body 7 is not adversely affected by being dented and deformed.

  Next, the mold 1 is opened, the hollow molded body 7 integrated with the core 27 is taken out, and the small-diameter portion 27b of the core 27 is cut, whereby the container-shaped hollow molded body 7 is completed.

  Therefore, according to the molding apparatus 10 of the hollow molded body 7 according to the present embodiment, a hollow molded body in which most of the machine oil in the core 27 is discharged and the amount of machine oil remaining in the core 27 is further reduced. 7 can be removed. For this reason, the time required for discharging the residual liquid from the hollow molded body 7 after demolding can be further reduced. In this manner, air and machine oil can be efficiently supplied and discharged in the hollow portion 25 of the core 27, and the intended resin hollow molded body 7 can be efficiently molded.

(Other embodiments)
The present invention may be configured as follows with respect to the above embodiment.

  That is, in the above embodiment, a sheet material 35 made of a thermosetting resin is used as a material for forming the hollow molded body 7, but the sheet material 35 is a sheet made of a thermoplastic resin such as a polyamide resin or a polypropylene resin. It may be a material. In this case, the mold is heated to 220-300 ° C and machine oil 100-110 ° C.

  Moreover, in the said embodiment, although the sheet | seat material 35 was coat | covered also on the bottom wall part 27d of the core 27, you may make it not coat | cover on this bottom wall part 27d.

  Moreover, in the said embodiment, although machine oil is used as a liquid, water and other liquids may be sufficient. In this case, the liquid needs to be heated to the same temperature as in the above embodiment. Moreover, although air is used as air, nitrogen gas etc. may be sufficient.

  Furthermore, in the said embodiment, although the bottomed square cylindrical container which has the taper part 7c is shown as a hollow molded object, the shape which does not have the taper part 7c, shapes, such as a cylinder, may be sufficient, and it is limited to the shape. Alternatively, it may have a complicated sectional structure with a bottom such as an instrument panel reinforcement or a side door reinforcement.

  In addition, the above embodiment is an essentially preferable illustration, Comprising: It does not intend restrict | limiting the range of this invention, its application thing, or a use.

It is sectional drawing which expands and shows a part of shaping | molding die in the shaping | molding apparatus of the resin hollow molded object of embodiment of this invention. It is a top view of an introduction nozzle. It is a hydraulic circuit diagram which shows the shaping | molding apparatus of a hollow molded object. It is a development top view of a sheet material. It is a perspective view of a hollow molded object.

DESCRIPTION OF SYMBOLS 1 Mold 3a 1st shaping | molding surface 5a 2nd shaping | molding surface 7 Hollow molded object 21 Air pipe 21a Air pipe front-end | tip 23 Liquid pipe 23a Liquid pipe front-end | tip 25 Hollow part 27 Core 27c Opening part 35 Sheet | seat material 43 Control apparatus

Claims (2)

By wrapping a resin sheet material around the outer surface of the expandable core so as to form a hollow portion and placing it in the mold, the pressure fluid is introduced into the core to be pressurized and expanded, A molding device that molds a resin hollow molded body by pressing the sheet material against a molding surface of a mold,
The core has one opening communicating with the hollow portion, extraordinary to the opening portion, a distal end and a liquid pipe the hollow portion of the liquid flows as the air pipe and the pressure fluid air flows Are set so that the air pipe tip is positioned above the liquid pipe tip ,
During the pressure molding of the sheet material, the pressurized liquid is fed into the hollow part from the liquid pipe to increase the pressure in the hollow part, and the air in the hollow part is discharged from the air pipe. A device for molding a hollow resin molded product, comprising: a control device that sends the air from the air pipe into the hollow portion and discharges the liquid in the hollow portion from the liquid pipe. In the shaping | molding apparatus of the resin hollow molded object of Claim 1,
An apparatus for molding a hollow resin molded product, wherein an extension length of the air pipe from the opening into the hollow portion is set longer than an extension length of the liquid pipe .

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