JP5705077B2 - Blow molding apparatus and blow molding method - Google Patents

Description

  The present invention relates to a blow molding apparatus and a blow molding method for molding a blow molded product having a built-in component made of a thermoplastic synthetic resin.

  Conventionally, as a structure of a hollow blow-molded product, for example, a fuel tank for an automobile or the like, a metal one has been used. However, in recent years, the weight of a vehicle is reduced, rust is not generated, and a desired shape is used. For example, a hollow thermoplastic synthetic resin has come to be used because of its easy molding.

  In the production of a hollow product made of a thermoplastic synthetic resin, a blow molding method has been often used because of the ease of molding a hollow body. In the blow molding method, a parison of a molten thermoplastic synthetic resin member is formed into a cylindrical shape and extruded from above, and the parison is sandwiched between molds and air is blown into the parison to produce a hollow body.

On the other hand, in the blow molding method, it is sometimes required to provide a blow molded product, for example, a built-in component such as a valve or a baffle plate for suppressing fuel flow noise inside the fuel tank.
Therefore, when providing a built-in component inside the blow molded product, a manufacturing apparatus as shown in FIG. 13 is used (for example, refer to Patent Documents 1 and 2). The built-in component 110 is held in the cavity of the blow molding die 120 by the built-in component holding rod 141, the parison 8 is lowered, and then the blow molding die 120 is closed and the parison 8 is held by the pinch plate 135. Thus, a blow molded product is formed.

  However, in this case, when the built-in component 110 becomes large, as shown in FIG. 14, when the built-in component 210 held by the holding rod 241 is molded by the blow molding die 220, the slide core 226 is inserted into the parison 8. Although the built-in component 210 holding the built-in component 210 is inserted, it is necessary to prevent the built-in component 210 from contacting the inner wall of the parison 8 when the built-in component 210 is inserted.

  Therefore, it is necessary to increase the diameter of the parison 8, but in that case, the portion other than that constituting the blow molded product in the parison 8, that is, the protruding portion generated outside the blow molded product at the time of blow molding increases. Was wasted. Moreover, the die core which extrudes the parison 8 becomes large and many are required.

Japanese Patent Laid-Open No. 9-174670 JP-A-8-72129

  Therefore, an object of the present invention is to provide a blow molding apparatus and method capable of performing blow molding with a high yield in the manufacture of blow molded products having built-in components.

The present invention of claim 1 for solving the above-mentioned problem is a blow molding apparatus for molding a blow molded product in which a built-in component is attached.
The blow molding device has a blow molding die for molding the outer wall of the blow molded product, a parison clamping device for clamping the lower end of the parison, and a built-in component holding device for holding the built-in components before blow molding,
The blow mold has a mold that is divided into two parts at the parting line. A cavity that forms a blow-molded product is formed on the open / close surface, and a slide core is formed on the inner surface of the cavity so that the slide core can be moved forward and backward. Provided, the internal part and the parison are sandwiched by the slide core, and the outer wall of the blow molded product is molded by the cavity.
A parison clamping device that clamps the lower end of the parison is provided below the blow mold, and the parison clamping device clamps a plurality of parison expanders inserted inside the lower end of the parison and an outer surface of the lower end of the parison. A parison outer clamping plate, the parison expander is slidably attached to the parison from the center outward;
The built-in component holding device includes a cylindrical built-in component hermetic guide tube that can hold the built-in component inside, a built-in component holding rod that can be slid vertically by holding the built-in component inside the built-in component hermetic guide tube, The component holding rod has a slidable hole and has a built-in component lower guide plate that closes the lower part of the built-in component hermetic guide tube,
When the blow mold is opened, the lower end of the parison located between the open cavities of the blow mold is expanded with multiple parison expanders, and the internal component airtight guide tube is inserted into the lower end of the parison. The built-in component airtight guide cylinder and the parison outer holding plate hold the lower end of the parison, and the parison is inflated and blow-molded. When the blow mold is closed, the internal part is located inside the parison, and the parison and the internal part are sandwiched by the slide core The blow molding device is configured to be movable forward and backward so that the built-in component holding rod comes out of the blow molding die.

  In the first aspect of the present invention, the blow molding device includes a blow molding die for molding the outer wall of the blow molded product, a parison clamping device for clamping the lower end of the parison, and a built-in component holding for holding the built-in component before blow molding. I have a device. For this reason, the blow molding which has a built-in component inside can be obtained by holding the lower end of a parison before blow molding, expanding the lower end of a parison, and inserting a built-in component in a parison.

  The blow mold has a mold that is divided into two parts at the parting line. A cavity that forms a blow-molded product is formed on the open / close surface, and a slide core is formed on the inner surface of the cavity so that the slide core can be moved forward and backward. The internal part and the parison are sandwiched by the slide core, and the outer wall of the blow molded product is formed by the cavity. For this reason, a blow molded product having the built-in component in a predetermined position in the cavity can be formed by holding the built-in component in the parison with the slide core.

  A parison clamping device that clamps the lower end of the parison is provided below the blow mold, and the parison clamping device includes a plurality of parison expanders inserted inside the lower end of the parison and a parison that clamps the outer surface of the lower end of the parison. An outer sandwiching plate is provided, and the parison expander is slidably attached to the parison outward from the center. For this reason, the lower end of the parison can be opened with a parison expander, the built-in component airtight guide tube can be inserted into the lower end of the parison, and when the pre-blow is performed to inflate the parison and insert the built-in component into the parison The built-in parts can be prevented from contacting the inner wall of the parison.

The built-in component holding device includes a cylindrical built-in component hermetic guide tube that can hold the built-in component inside, a built-in component holding rod that can be slid vertically by holding the built-in component inside the built-in component hermetic guide tube, The component holding bar has a slidable hole and a built-in component lower guide plate that closes the lower part of the built-in component hermetic guide tube. For this reason, the built-in component hermetic guide tube can hold the built-in component so as to be movable up and down, and the built-in component hermetic guide tube can be hermetically sealed.
Further, the built-in component only needs to be held inside the built-in component hermetic guide tube, and a wide range of built-in components can be used. Furthermore, it is easy to change the specifications of the built-in component by using the built-in component hermetic guide cylinder as the standby position before insertion of the built-in component.

  When the blow mold is opened, the lower end of the parison located between the open cavities of the blow mold is expanded with a plurality of parison expanders. For this reason, since the lower end of a parison can be expanded, it is not necessary to increase the outer diameter of the parison in order to insert a built-in component, and the parison material can be saved.

  After the built-in component airtight guide tube is inserted into the lower end of the parison, the lower end of the parison is sandwiched between the built-in component airtight guide tube and the outer holding plate of the parison, and the parison is inflated and pre-blowed. The built-in component is positioned in the parison by the built-in component holding rod from the inside, and the built-in component is held at a position facing the cavity. Since the outer diameter of the parison swells, when the built-in component is inserted, the built-in component can be positioned at a predetermined position of the cavity by the built-in component holding rod without the built-in component contacting the inner wall of the parison.

  Built-in components are located inside the parison when the blow mold is closed, and the built-in component holding rod is configured to be able to move forward and backward so that the built-in component holding rod comes out of the blow mold after the parison and the built-in components are sandwiched by the slide core. It was done. For this reason, blow molding can be performed while the built-in component is held at a predetermined position in the cavity, and a blow molded product in which the built-in component is arranged at the predetermined position can be obtained.

  The present invention of claim 2 is a blow molding apparatus in which an upper end of a built-in component hermetic guide tube and a pre-blow outlet that blows out gas when the lower end of the parison is sandwiched between the outer parison plates of the parison are formed at the upper end of the parison expander. is there.

  In the second aspect of the present invention, when the upper end of the built-in component hermetic guide tube and the lower end of the parison are clamped by the outer pin of the parison, a pre-blow outlet that blows out gas is formed at the upper end of the parison expander. For this reason, gas can be blown out from the pre-blow outlet formed at the tip of the parison expander while holding the upper end of the built-in component hermetic guide cylinder and the lower end of the parison between the parison outer clamping plates, and the parison can be inflated with pre-blow It is easy to insert the built-in parts into the parison.

  According to a third aspect of the present invention, the parison expander is formed so that the upper end of the built-in component hermetic guide cylinder can be brought into contact with the slide mechanism, and the upper part of the built-in component hermetic guide cylinder is formed with a storage recess for the parison expander. It is a molding device.

  According to the third aspect of the present invention, the parison expander is formed so as to be able to come into contact with the upper end of the built-in component hermetic guide tube by a slide mechanism, and the storage recess for the parison expander is formed at the upper end of the built-in component hermetic guide tube. For this reason, when the parison outer clamping plate clamps the outside of the lower end of the parison, the built-in component airtight guide tube and its outer surface are integrated, and the parison expander can hold and hold the inner side of the parison airtight. .

  The fourth aspect of the present invention is a blow molding apparatus having an upper pinch plate that clamps the upper end of the parison at a position away from the upper blow molding die of the blow molding die.

  In this invention of Claim 4, it has an upper pinch board which clamps the upper end of a parison in the position away from the upper blow molding die of a blow molding die. Therefore, the upper end of the parison can be kept airtight when pre-blowing, and the parison can be kept inflated when the built-in component is inserted.

  According to a fifth aspect of the present invention, the parison outer clamping plate is divided into two parts, and the blow molding device is formed so as to move in a direction in which it abuts against the end face of the built-in component hermetic guide cylinder. It is.

  According to the present invention of claim 5, the parison outer clamping plates are each formed by being divided into two parts, and each is formed so as to move in a direction in which the cylinder abuts against the end face of the built-in component hermetic guide cylinder. For this reason, the lower end of a parison can be reliably airtightly clamped by a parison outer side clamping plate and a built-in component airtight guide cylinder.

The present invention of claim 6 is a blow molding method for molding a blow molded product in which a built-in component is attached.
The blow molding method uses a blow molding die for molding the outer wall of the blow molded product, a parison clamping device for clamping the lower end of the parison, and a built-in component holding device for holding the built-in component before blow molding,
The blow mold has a mold that is divided into two parts at the parting line. A cavity that forms a blow-molded product is formed on the open / close surface, and a slide core is formed on the inner surface of the cavity so that the slide core can be moved forward and backward. Provided,
The parison clamping device has a plurality of parison expanders inserted inside the lower end of the parison and a parison outer clamping plate that clamps the outer surface of the lower end of the parison. The parison expander is outward from the center with respect to the parison. Is slidably mounted on
The built-in component holding device has a cylindrical built-in component hermetic guide tube that can hold the built-in component inside, a built-in component holding rod that can be slid vertically by holding the built-in component inside the built-in component hermetic guide tube, and built-in The component holding rod has a slidable hole and has a built-in component lower guide plate that closes the lower part of the built-in component hermetic guide tube,
Open the blow mold at the parting line, hang the parison in the part where the cavity is opened, expand the lower end of the parison with multiple parison expanders, and then install the built-in component airtight guide tube at the lower end of the parison. Insert and hold the internal part airtight guide cylinder and the parison outer clamping plate at the lower end of the parison, insert the gas into the parison, inflate the parison and perform pre-blow, then hold the internal part from the internal part airtight guide cylinder Hold the built-in part with a rod, place the built-in part in the parison, hold the built-in part in a position facing the cavity, close the blow mold, and hold the parison and the built-in part with the slide core After that, the built-in component holding rod comes out of the blow mold, and after the blow mold is completely closed, gas is blown into the parison. A blow molding method for molding a blow-molded article.

  In the present invention of claim 6, the blow molding method comprises: a blow molding die for molding the outer wall of the blow molded product, a parison clamping device for clamping the lower end of the parison, and a built-in component holding for holding the built-in component before blow molding. Use equipment. For this reason, the blow molding which has a built-in component inside can be obtained by hold | maintaining the lower end of a parison before blow molding, inserting a built-in component in a parison, and extending the lower end of a parison.

  The blow mold has a mold that is divided into two parts at the parting line. A cavity that forms a blow-molded product is formed on the open / close surface, and a slide core is formed on the inner surface of the cavity so that the slide core can be moved forward and backward. Provided. For this reason, a blow molded product having the built-in component in a predetermined position in the cavity can be formed by holding the built-in component in the parison with the slide core.

  The parison clamping device has a plurality of parison expanders inserted inside the lower end of the parison and a parison outer clamping plate that clamps the outer surface of the lower end of the parison. The parison expander slides laterally with respect to the parison. Installed as possible. For this reason, the lower end of the parison can be opened with a parison expander, the built-in component airtight guide tube can be securely inserted into the lower end of the parison, the preblow is performed, the parison is inflated, and the built-in component is inserted into the parison When this is done, the built-in parts can be prevented from coming into contact with the inner wall of the parison.

The built-in component holding device has a cylindrical built-in component hermetic guide tube that can hold the built-in component inside, a built-in component holding rod that can be slid vertically by holding the built-in component inside the built-in component hermetic guide tube, and built-in The component holding bar has a slidable hole and a built-in component lower guide plate that closes the lower part of the built-in component hermetic guide tube. For this reason. The built-in component hermetic guide tube can hold the built-in component so that it can be moved up and down, and the built-in component hermetic guide tube can be hermetically sealed.
Further, the built-in component only needs to be held inside the built-in component hermetic guide tube, and a wide range of built-in components can be used. Furthermore, it is easy to change the specifications of the built-in component by using the built-in component hermetic guide cylinder as the standby position before insertion of the built-in component.

  Open the blow molding die at the parting line, hang down the parison in the part where the cavity is opened, expand the lower end of the parison with multiple parison expanders, then insert the built-in component hermetic guide tube at the lower end of the parison . For this reason, the lower end of the parison can be expanded, and it is not necessary to increase the outer diameter of the parison in order to insert a built-in component, and the parison material can be saved.

  Hold the lower end of the parison with the built-in component airtight guide cylinder and the outer pin of the parison, insert the gas into the parison, inflate the parison, perform pre-blow, and then incorporate it from the built-in component airtight guide cylinder with the built-in component holding rod Hold the part and place the built-in part in the parison. As a result, the outer diameter of the parison expands, so that when the built-in component is inserted, the built-in component can be positioned at a predetermined position of the cavity by the built-in component holding rod without contacting the inner wall of the parison. it can.

  When the internal parts are held in a position facing the cavity and the blow mold is closed, the internal parts are located inside the parison, and the internal parts are held after the parison and the internal parts are clamped by the slide core. After the rod comes out of the blow molding die and the blow molding die is completely closed, gas is blown into the parison to form a blow molded product. Therefore, it is possible to obtain a blow molded product in which the built-in component is arranged at a predetermined position without shifting the built-in component in the parison. Thereafter, the blow molded product can be taken out of the cavity by opening the blow mold.

  According to the seventh aspect of the present invention, after the upper end of the built-in component hermetic guide cylinder and the lower end of the parison are sandwiched between the outer parison plates of the parison, the pre-blowing is performed by blowing gas from the pre-blow outlet formed at the upper end of the parison expander. This is a blow molding method.

  In this invention of Claim 7, after pinching the upper end of a built-in component airtight guide cylinder and the lower end of a parison with a parison outer clamping plate, gas is blown out from a preblow outlet formed at the upper end of a parison expander, went. For this reason, it is possible to inflate the parison with the pre-blow while holding the upper end of the built-in component hermetic guide cylinder and the lower end of the parison between the parison outer clamping plates, and it is easy to insert the built-in component into the parison.

  According to the eighth aspect of the present invention, the storage recess of the parison expander is formed at the upper end of the built-in component hermetic guide cylinder, and the parison expander is stored in the storage recess of the parison expander by the slide mechanism, and then the built-in component hermetic guide. This is a blow molding method in which the upper end of the cylinder and the parison expander are in contact with the inner surface of the parison, and the outer pin of the parison is in contact with the outer surface of the parison to sandwich the lower end of the parison.

  According to the present invention of claim 8, the storage recess of the parison expander is formed at the upper end of the built-in component hermetic guide cylinder, and the parison expander is housed in the storage recess of the parison expander by the slide mechanism, and then the built-in component hermetic guide. The upper end of the tube and the parison expander are in contact with the inner surface of the parison, and the outer pinion pin of the parison is in contact with the outer surface of the parison to sandwich the lower end of the parison. For this reason, the parison expander is integrated with the built-in component hermetic guide cylinder and abuts against the inside of the parison to keep the parison airtight, and the parison outer holding plate abuts against the outer surface of the parison. The lower end of can be clamped.

  The present invention of claim 9 is a blow molding method in which the upper end of the parison is clamped by an upper pinch plate provided at a position distant from the upper blow molding die of the blow molding die before pre-blowing.

  In the present invention of claim 9, before the pre-blow, the upper end of the parison is clamped by an upper pinch plate provided at a position separated from the upper blow molding die of the blow molding die. Therefore, the upper end of the parison can be kept airtight when pre-blowing, and the parison can be kept inflated when the built-in component is inserted.

  The present invention of claim 10 is a blow molding method in which each of the parison outer clamping plates is formed by being divided into two parts, and each of the parison outer clamping plates is moved in a direction in contact with the end face of the built-in component hermetic guide cylinder.

  According to the present invention of claim 10, the parison outer clamping plates are each formed by being divided into two parts, and each is moved in a direction in which it abuts against the end face of the built-in component hermetic guide cylinder by the cylinder. For this reason, the lower end of a parison can be reliably airtightly clamped by a parison outer side clamping plate and a built-in component airtight guide cylinder.

In the present invention, the built-in component holding device has a built-in component hermetic guide tube, a built-in component holding rod, and a built-in component lower guide plate, so that the built-in component hermetic guide tube holds the built-in component in a freely movable manner, Pre-blowing can be performed with the built-in component airtight guide tube being airtight.
Hold the lower end of the parison with the upper end of the built-in component airtight guide tube and the lower end of the parison with the outer pin of the parison, inflate the parison, and when inserting the built-in component, the built-in component does not contact the inner wall of the parison, With the built-in component holding rod, the built-in component can be positioned at a predetermined position of the cavity. When extruding the parison, it is not necessary to increase the outer diameter of the parison, and the parison material can be saved.

It is a fuel tank perspective view which is an embodiment of the invention. It is a top view of a parison clamping device and a built-in component holding device of an embodiment of the invention. It is sectional drawing of the process in which the blow molding apparatus of embodiment of this invention manufactures a blow molded product, and is a sectional view which shows the state which the parison entered in the blow molding die. It is sectional drawing of the process in which the blow molding apparatus of embodiment of this invention manufactures a blow molded product, and is sectional drawing which shows the state which opened the lower end of the parison with the parison expander. It is sectional drawing of the process in which the blow molding apparatus of embodiment of this invention manufactures a blow molded product, and is sectional drawing which shows the state which clamped the lower end of a parison with the upper end of a parison outer clamping board and a built-in component airtight guide cylinder. . It is sectional drawing of the process in which the blow molding apparatus of embodiment of this invention manufactures a blow molded product, The state which performed the pre-blow by pinching the lower end of a parison with the upper end of a parison outer clamping plate and a built-in component airtight guide cylinder. It is sectional drawing shown. It is a model perspective view which shows the state which clamps a parison in the upper part of the parison clamping apparatus and built-in component holding | maintenance apparatus of embodiment of this invention. It is the model perspective view which expanded the upper end part of the parison expander in the state which clamps a parison in the upper part of the parison clamping apparatus and built-in component holding | maintenance apparatus of embodiment of this invention. It is sectional drawing of the process in which the blow molding apparatus of embodiment of this invention manufactures a blow molded product, and is sectional drawing which shows the state which inserted the internal component in the parison from the lower end of a parison. It is sectional drawing of the process in which the blow molding apparatus of embodiment of this invention manufactures a blow molded product, and is sectional drawing which shows the state which clamped the internal component in a parison with the slide core. FIG. 5 is a cross-sectional view of a process for producing a blow molded product by the blow molding apparatus according to the embodiment of the present invention, in which a built-in component in a parison is sandwiched between slide cores and a built-in component holding rod is pulled out from a blow molding die FIG. It is sectional drawing of the process in which the blow molding apparatus of embodiment of this invention manufactures a blow molded product, shows the state which clamped the internal component in a parison with a slide core, closed the blow molding die, and was blow molded. It is sectional drawing. It is a perspective view of the apparatus with which the slide core and drive control pin of the conventional blow molding apparatus manufacture a blow molded product. It is sectional drawing of the process of manufacturing the blow molded product of the other conventional blow molding apparatus, and is sectional drawing which shows the state which the parison entered in the blow molding die.

  A blow molding apparatus according to an embodiment of the present invention will be described with reference to FIGS. 1 to 12, taking as an example a blow molding apparatus for manufacturing a fuel tank 1 for automobiles which is a blow molded product. The present invention will be described by taking the fuel tank 1 having the built-in component 10 as an example, but other blow molded products having the built-in component 10 can also be used.

FIG. 1 is a perspective view of a fuel tank 1 manufactured by a blow molding apparatus according to an embodiment of the present invention.
In the embodiment of the present invention, a fuel tank 1 manufactured by a blow molding apparatus has a pump unit mounting hole 4 for taking a fuel pump (not shown) and the like into and out of the fuel tank 1 as shown in FIG. Is formed on the upper surface. A fuel injection hole 5 for injecting fuel from an inlet pipe (not shown) is formed on the side surface or the upper surface of the fuel tank 1.

An outer peripheral rib 2 is formed around the entire circumference of the fuel tank 1, and mounting holes 3 are formed at predetermined locations such as corner portions of the outer peripheral rib 2. The fuel tank 1 is attached to the vehicle body by bolting 3 and the vehicle body.
Furthermore, on the upper surface of the fuel tank 1, there are formed attachment holes 6 at various places for connecting a hose or the like for collecting the internal fuel vapor.

  The fuel tank 1 manufactured in the present embodiment is manufactured by a blow molding manufacturing apparatus to be described later. The outer wall of the fuel tank 1 is formed by blow molding, and the outer wall is formed by one layer or multiple layers. In the case of multiple layers, for example, a skin layer, an external body layer, an external adhesive layer, a barrier layer, an internal adhesive layer, and an internal body layer are formed in order from the outside.

Inside the fuel tank 1, for example, a pillar for reinforcing the fuel tank 1, a partition plate for preventing the generation of undulation noise, a fuel pump, A box or the like for mounting a canister or the like is attached as the built-in component 10.
The built-in component 10 can be formed of a fuel-resistant thermoplastic synthetic resin such as polyacetal or high-density polyethylene (HDPE). As a result, the strength of the fuel tank 1 can be improved, and even if the fuel tank 1 is attached to the inside of the fuel tank 1, the rigidity does not decrease due to swelling by the fuel oil or the like.

  A blow molding apparatus according to an embodiment of the present invention and a method of manufacturing the fuel tank 1 by blow molding using the apparatus will be described with reference to FIGS. The blow molding device holds a blow molding die 20 for molding a blow molded product, a parison clamping device 30 for clamping the lower end of the parison 8, a built-in component 10 in the built-in component airtight guide tube 42, and a blow mold. The built-in component holding device 40 is inserted into the parison 8 in the mold 20.

First, the parison clamping device 30 will be described with reference to FIGS.
A parison clamping device 30 that clamps the lower end of the parison 8 is provided below the blow molding die 20, and the parison clamping device 30 is inserted into the lower end of the parison 8 that comes out from the lower portion of the blow molding die 20. An expander 31 and a parison outer clamping plate 32 that clamps the outer surface of the lower end of the parison are provided.

  A plurality of parison expanders 31 are attached so that the lower end of the parison 8 can be expanded. In the present embodiment, four pieces are attached so as to correspond to four corners of a built-in component hermetic guide cylinder 42 described later. When the parison expander 31 comes into contact with the built-in component airtight guide tube 42, the parison expander 31 is accommodated in the built-in component airtight guide tube recess 45 formed in the built-in component airtight guide tube 42, and is integrated with the built-in component airtight guide tube 42. Thus, the outer surface of the built-in component airtight guide cylinder 42 and the outer surface uniform can be formed, and the inner surface of the parison 8 can be airtightly sandwiched.

  The parison expander 31 is attached by a parison cylinder 33 so as to be movable outward from the center (perpendicular to the parison). The parison expander 31 can abut the inner surface of the lower end of the parison 8 and increase the inner diameter of the parison 8 by retreating the parison cylinder 33.

The parison expander 31 can be left inflated so that the lower end of the parison 8 is not crushed. When the upper end of the built-in component airtight guide cylinder 42 is inserted into the parison 8, the inner surface of the parison 8 is expanded. The inner surface of the lower end of the parison 8 can be brought into contact with the outer surface of the upper end of the built-in component airtight guide cylinder 42.
As shown in FIG. 8, a pre-blow outlet 34 is formed at the tip of the parison expander 31 so that a gas such as air can be ejected into the parison 8.

  The parison outer clamping plate 32 is formed with a recessed portion 32 b corresponding to the outer peripheral shape of the built-in component airtight guide cylinder 42 and the parison expander 31. Thereby, the lower end of the parison 8 can be clamped by the parison expander 31 and a built-in component airtight guide cylinder 42 to be described later and the parison outer clamping plate 32. Moreover, the parison outer side clamping board 32 is divided | segmented into multiple pieces, and is formed so that a slide is possible so that the lower end of the parison 8 may be clamped, respectively. In this embodiment, it is divided into two parts, but may be divided into three or more parts.

  When the parison outer clamping plate 32 slides in the direction of the built-in component airtight guide tube 42 (the center direction of the parison 8), the outer periphery of the lower end of the parison 8 is pressed, and the upper end of the built-in component airtight guide tube 42 and the parison expander 31 The parison 8 can be securely clamped with the parison outer clamping plate 32 to prevent gas leakage and prevent the lower end of the parison 8 from being crushed. Moreover, since the volume in the parison 8 can be maintained large and a sufficient gas can be sealed in the parison 8, the parison 8 is slightly inflated before blowing to bring the parison 8 into close contact with the mold. Pre-blow can be performed.

  Next, the built-in component holding device 40 will be described with reference to FIGS. The built-in component holding device 40 has a cylindrical built-in component hermetic guide tube 42, and holds the built-in component 10 inside the built-in component hermetic guide tube 42 and moves vertically so that the built-in component 10 can be inserted into the parison 8. The built-in component holding rod 41 and the built-in component lower guide plate 43 capable of closing the lower part of the built-in component airtight guide cylinder 42 are configured.

  The built-in component airtight guide tube 42 is formed in a hollow tube shape, and the built-in component 10 is housed in the hollow and is held so as to be movable in the vertical direction. The cross-sectional shape of the built-in component airtight guide cylinder 42 can be any of a circular shape, an elliptical shape, and a polygonal shape so that the built-in component 10 can be accommodated. The hollow cylindrical wall of the built-in component airtight guide cylinder 42 can be formed in a bellows shape.

For this reason, the built-in component holding rod 41 holds the built-in component 10 in an up-and-down manner so that the built-in component hermetic guide tube 42 is hermetically sealed when the lower end of the parison 8 is sandwiched between the upper ends of the built-in component hermetic guide tube 42. Can be.
The built-in component 10 only needs to be held inside the built-in component hermetic guide cylinder 42, and a wide range of built-in components 10 can be used. Furthermore, by changing the standby position before insertion of the built-in component 10 to the built-in component airtight guide tube 42, it is easy to change the specifications of the built-in component 10.

The built-in component lower guide plate 43 is formed with a built-in component lower guide hole 44 so that the built-in component holding rod 41 can slide. The built-in component lower guide plate 43 can keep the inside of the built-in component airtight guide tube 42 airtight while sliding in the built-in component airtight guide tube 42 according to the sliding of the built-in component holding bar 41 in the vertical direction. . A plurality of built-in component holding bars 41 can be provided according to the size of the built-in component 10. The built-in component lower guide plate 43 can also be attached to the built-in component holding bar 41 so as to move up and down in the built-in component airtight guide cylinder 42 as the built-in component holding bar 41 moves up and down.
A built-in component hermetic guide cylinder recess 45 capable of accommodating the parison expander 31 is formed at the upper end of the built-in component hermetic guide cylinder 42 as described above.

Next, the blow mold 20 will be described with reference to FIG.
The blow molding die 20 is divided into two parts by a parting line, and is slid so that it can be opened to the left and right by a blow molding die moving device (not shown). The blow molding die 20 has a cavity 22 that forms the fuel tank 1 therein. Further, slide cores 26 are provided at portions corresponding to the cavities 22 of the left and right blow molds 20.

The slide core 26 forms part of the inner surface of the cavity 22 when the blow molding die 20 is closed and the slide core 26 is retracted, and the blow molding die 20 is opened and advanced into the cavity 22. In some cases, a later-described built-in component 10 and a parison 8 are held. The parison 8 is pushed downward from a nozzle (not shown) provided in the upper part of the blow molding die 20.
The blow molding dies 20 formed by being divided into two at the parting line abut each other around the cavity 22 at the time of clamping. In FIG. 12, the upper contact surface 23 a of the mold upper portion 23 of the blow molding mold 20 is in contact with the lower contact surface 24 a of the lower mold portion 24.

Next, the manufacturing method of the fuel tank 1 for motor vehicles which is a blow molded product using the blow molding apparatus of embodiment of this invention is demonstrated based on FIGS.
An upper pinch plate 60 is provided on the upper part of the blow molding die 20. A parison clamping device 30 is attached to the lower part of the blow molding die 20 as shown in FIGS.
As shown in FIG. 3, in blow molding, first, the blow molding die 20 is opened, and a space constituting the cavity 22 is opened, in which the parison 8 is inserted from an upper nozzle (not shown). Extruded. Then, the lower end of the parison 8 reaches below the mold lower part 24 of the blow molding mold 20.

Next, as shown in FIG. 4, a plurality of parison expanders 31 enter and come into contact with the inner surface of the lower end of the parison 8. And the parison expander 31 opens in the direction away from the center of the parison 8 as shown by the arrow in FIG.
At that time, the built-in component holding device 40 holding the built-in component 10 is positioned below the lower end of the parison 8.

Next, as shown in FIG. 5, the upper pinch plate 60 is closed and the upper portion of the parison 8 is closed.
The built-in component hermetic guide cylinder 42 is inserted into the lower end of the parison 8. The parison expander 31 comes into contact with the upper end of the built-in component airtight guide tube 42 and is housed in the built-in component airtight guide tube recess 45. The outer surface of the lower end of the parison 8 is pressed by the parison outer clamping plate 32 and moves toward the built-in component airtight guide cylinder 42. The lower end of the parison 8 is clamped by the parison outer clamping plate 32 and the built-in component airtight guide cylinder 42. At this time, the parison expander 31 is integrated with the built-in component airtight guide cylinder 42 and sandwiches the inner surface of the lower end of the parison 8. The lower end of the built-in component airtight guide cylinder 42 is closed by the built-in component lower guide plate 43, and the lower end of the parison 8 becomes airtight.

  Next, as shown in FIGS. 6 to 8, pre-blow is performed. Pre-blowing can be performed by inflating the parison 8 by blowing gas into the parison 8 from the tip of the parison expander 31. As shown in FIG. 8, a pre-blow outlet 34 is formed at the tip of the parison expander 31. Gas can be blown into the parison 8 from the pre-blow outlet 34. In the present embodiment, air is used as the gas blown into the parison 8.

At this time, in the upper part of the parison 8, the parison 8 is blocked by the upper pinch plate 60 as described above. In the lower part of the parison 8, the parison 8 is closed by the built-in component airtight guide cylinder 42, the parison expander 31, and the built-in component airtight guide cylinder 42 as described above to prevent air escape. In addition, at the lower part of the built-in component airtight guide cylinder 42, the built-in component lower guide plate 43 is blocked to prevent escape of air.
As shown in FIG. 7, the parison expander 31 is slid by a parison cylinder 33.

  Next, as shown in FIG. 9, the built-in component holding rod 41 holding the built-in component 10 from the built-in component airtight guide cylinder 42 is slid upward in the parison 8 inflated by pre-blow, so that the blow mold 20 The built-in component 10 is positioned at the position of the cavity 22. At this time, since the parison 8 is swollen by pre-blow, the built-in component 10 does not come into contact with the inner wall of the parison 8.

Then, as shown in FIG. 10, the blow molding die 20 is slightly closed and a plurality of slide cores 26 provided on the blow molding die 20 are slid. At this time, since the plurality of slide cores 26 are provided at positions corresponding to the built-in component 10, the parison 8 can be pressed so as to be sandwiched between the built-in component 10 and the slide core 26.
At this time, the built-in component lower guide plate 43 is positioned at the upper end of the built-in component airtight guide tube 42 so that the air in the parison 8 cannot escape.

  Then, since the inner surface of the parison 8 is still in a molten state, the tip of the built-in component 10 and the parison 8 can be fused. At this time, since the built-in component 10 is held by the built-in component holding rod 41 and the slide core 26, the built-in component 10 can be reliably attached to a predetermined position on the inner surface of the outer wall of the fuel tank 1.

  After that, as shown in FIG. 11, the built-in component holding bar 41 is lowered while the built-in component 10 is held by the slide core 26, and is removed from the blow molding die 20. Since the built-in component 10 is held by the slide core 26, the built-in component 10 can be maintained at a predetermined position. At this time, since the lower end of the parison 8 is held and sealed by the parison outer holding plate 32 of the parison holding device 30 and the built-in component lower guide plate 43 is positioned and sealed at the lower end of the built-in component airtight guide tube 42, Air does not leak from inside the parison 8.

Furthermore, as shown in FIG. 12, the blow molding die 20 is further closed, and the blow molding die 20 is completely closed. Thereby, the front end and the rear end of the parison 8 can be completely closed by the blow molding die 20.
In the parison 8, the upper contact surface 23a of the upper mold portion 23 and the lower contact surface 24a of the lower mold portion 24 of each of the blow molds 20 formed by dividing the parison 8 into two are in contact with each other. The upper and lower parts of the parison 8 can be closed. Alternatively, a pinch plate as shown in the prior art may be provided between the blow molding die 20 and the parison clamping device 30 to close the upper or lower portion of the parison 8.

  Then, the top and bottom of the parison 8 are cut by slide cutters (not shown) provided on the top and bottom of the blow molding die 20. Then, air is blown into the inside of the parison 8 from the air nozzle 27, and the outer surface of the parison 8 is pressed against the inner surface of the cavity 22 of the blow molding die 20 to form the shape of the fuel tank 1.

  At this time, the front end surface of the slide core 26 and the inner surface of the cavity 22 of the blow molding die 20 can be flush with each other. Further, air is blown into the inside of the parison 8 from the air nozzle 27, and the outer surface of the parison 8 is completely pressed against the blow molding die 20, so that the shape of the fuel tank 1 is completely formed. Then, air is circulated inside the parison 8 to complete blow molding. Thereafter, the blow mold 20 is opened and the fuel tank 1 is taken out.

DESCRIPTION OF SYMBOLS 1 Fuel tank 8 Parison 10 Built-in component 20 Blow molding die 22 Cavity 26 Slide core 30 Parison clamping device 31 Parison expander 32 Parison outer clamping plate 40 Built-in component holding device 41 Built-in component holding rod 42 Built-in component airtight guide cylinder 43 Built-in Parts lower guide plate

Claims (10)

In blow molding equipment that molds blow molded products with built-in parts attached inside,
The blow molding device has a blow molding die for molding the outer wall of a blow molded product, a parison clamping device for clamping the lower end of the parison, and a built-in component holding device for holding the built-in component before blow molding,
The blow molding die has a mold formed by dividing it into two parts by a parting line, and a cavity for forming the blow molded product is formed on the opening / closing surface so that the cavity can be moved forward and backward on the inner surface of the cavity. A slide core is provided, the internal part and the parison are sandwiched by the slide core, and the outer wall of the blow molded product is molded by the cavity.
A parison clamping device that clamps the lower end of the parison is provided below the blow mold, and the parison clamping device includes a plurality of parison expanders that are inserted into the lower end of the parison, and a lower end of the parison. A parison outer sandwiching plate sandwiching the outer surface of the parison, and the parison expander is slidably attached to the parison from the center to the outer direction,
The built-in component holding device includes a cylindrical built-in component hermetic guide tube that can hold the built-in component inside, and a built-in component holding device that can hold the built-in component inside the built-in component hermetic guide tube and slide up and down. A built-in component lower guide plate that has a rod and a hole in which the built-in component holding rod can slide, and closes the built-in component hermetic guide tube;
When the blow mold is opened, the lower end of the parison located between the cavities opened by the blow mold is expanded by a plurality of the parison expanders, and the built-in component airtight at the lower end of the parison After the guide cylinder is inserted, the lower end of the parison is sandwiched between the built-in component hermetic guide cylinder and the outer parison plate, and the parison is inflated and pre-blowed. The built-in component is positioned in the parison by the built-in component holding rod, the built-in component is held at a position facing the cavity, and the built-in component is placed inside the parison when the blow mold is closed. After the part is positioned and the parison and the built-in part are sandwiched by the slide core, the built-in part holding rod is the blow mold. Retractably constructed blow molding apparatus so as to exhaust.   2. The blow molding according to claim 1, wherein when the upper end of the built-in component airtight guide cylinder and the lower end of the parison are clamped by the outer parison plate of the parison, a pre-blow outlet is formed at the upper end of the parison expander. apparatus.   The said parison expander is formed so that it can contact | abut by the slide mechanism at the upper end of the said internal component airtight guide cylinder, The storage recessed part of the said parison expander was formed in the upper end of the said internal component airtight guide cylinder. Item 3. The blow molding apparatus according to Item 2.   The blow molding apparatus according to any one of claims 1 to 3, further comprising an upper pinch plate that sandwiches an upper end of the parison at a position away from an upper blow molding die of the blow molding die.   The parison outer clamping plate is formed in two parts, and each cylinder is formed so as to move in a direction in contact with the end face of the built-in component airtight guide cylinder. The blow molding apparatus of Claim 1. In a blow molding method for molding a blow molded product in which a built-in component is attached,
The blow molding method uses a blow molding die for molding the outer wall of a blow molded product, a parison clamping device for clamping the lower end of the parison, and a built-in component holding device for holding the built-in component before blow molding,
The blow molding mold has a mold formed by dividing it into two parts by a parting line, and a cavity for forming the blow molded product is formed on the opening / closing surface, and the cavity can be moved forward and backward on the inner surface of the cavity. Provide a slide core,
The parison clamping device has a plurality of parison expanders inserted into the lower end of the parison and a parison outer clamping plate that clamps the outer surface of the lower end of the parison, and the parison expander is attached to the parison. Slidably mounted from the center to the outside,
The built-in component holding device includes a cylindrical built-in component hermetic guide cylinder capable of holding the built-in component therein, and a built-in component holding rod that can be slid vertically by holding the built-in component inside the built-in component hermetic guide tube. And a built-in component lower guide plate that has a hole in which the built-in component holding rod can slide and closes the built-in component airtight guide tube,
Open the blow mold at the parting line, hang the parison in the part where the cavity is opened, expand the lower end of the parison with a plurality of the parison expanders, and then lower the lower end of the parison. After inserting the built-in component hermetic guide cylinder, holding the built-in part hermetic guide cylinder and the lower end of the parison with the outer pinion plate of the parison, inserting gas into the parison and inflating the parison to perform pre-blow After holding the built-in component from the inside of the built-in component airtight guide cylinder by the built-in component holding rod, positioning the built-in component in the parison, and holding the built-in component in a position facing the cavity After the blow mold is closed and the parison and the built-in component are clamped by the slide core, the built-in component holding There exits from the blow molding mold, the blow mold after the completely closed, blow molding method for molding a blow-molded article blowing gas into the parison.   7. The method according to claim 6, wherein after the upper end of the built-in component airtight guide tube and the lower end of the parison are sandwiched by the outer parison plate of the parison, the gas is blown out from a preblow blowout port formed at the upper end of the parison expander. The blow molding method described.   A storage recess of the parison expander is formed at an upper end of the built-in component hermetic guide cylinder, and the parison expander is stored in the storage recess of the parison expander by a slide mechanism, and then the upper end of the built-in component hermetic guide cylinder. The blower according to claim 6 or 7, wherein the parison expander abuts against the inner surface of the parison, and the outer pinion plate of the parison abuts against the outer surface of the parison to sandwich the outer side of the lower end of the parison. Molding method.   The upper end of the parison is clamped by an upper pinch plate provided at a position away from the upper blow molding die of the blow molding die before the pre-blow. The blow molding method described.   The said parison outer side clamping board is divided | segmented into 2 parts, respectively, and moves to the direction contact | abutted with respect to the end surface of the said built-in components airtight guide cylinder with a cylinder, respectively. The blow molding method described.

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