JPH0435150Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial field of application> This invention is a blow-molded synthetic resin hollow molded product, especially a parison used for two-dimensional or three-dimensional synthetic resin pipes, ducts, etc. This invention relates to a parison feeding device for feeding into a mold cavity.

<Prior art and its problems> This type of parison feeding device
A parison of a predetermined length extrusion-molded according to Publication No. 41522 is transferred onto the cavity of the lower mold by a conveyor, and after the tip thereof faces one end of this cavity, the conveyor is driven and simultaneously the parison is moved in two or more dimensions. A device was described in which the parison is fed and stored by moving the parison into the cavity, but it requires a conveyor and a drive device to move the conveyor in two or more directions, and the entire feeding machine is It has the disadvantage of being large and complex.

There is Japanese Patent Publication No. 61-32128, which improves the structure of the mold without using such a conveyor. , are formed into convex bent cavities, and an appropriate number of small holes are provided in the cavity of the female mold for sucking parison air, while an appropriate number of small holes for blowing out heated air are provided in the cavity of the male mold. First, the parison is sucked toward the female mold through a small hole for air suction, and
A device that blows out heated air from the small holes for blowing heated air while moving the male mold forward toward the parison, and adsorbs the parison to the female mold as if pressing the parison into the cavity of the female mold, and supplies and stores the parison. In such a supply device, it is necessary to drill the small hole groups in the male and female molds, which complicates the structure of these molds and also requires additional equipment for sucking air into the molds and blowing out heated air. Ancillary equipment is required, and the shape of the curved pipe that can be formed is limited to almost a dogleg shape, so the versatility of this feeding device is lacking.

In JP-A-61-179718, which is a prior art divided from the above-mentioned JP-B-61-32128, a parison is fed hanging from a die of an extruder between a set of molding molds, and A guide tool having a convex curved surface portion at the tip that matches the shape of the curved pipe to be formed is advanced from the horizontal direction toward the parison, and the parison is moved along the groove formed in the convex curved surface portion of this guide tool. After approaching the half-split curved tube-shaped portions of the cavities of these split molds while deforming them with pressure, the guide tool is retreated, and during this time, the parison, which has been transformed into a bent pipe, is installed in the cavity of one of the split molds. A device is described in which air is sucked into a cavity through an appropriate number of small air suction holes, and the device is supplied and stored.As with the parent application, the structure of the mold is complex, and the guide tool has a convex curved surface. Therefore, it has a drawback that it is not possible to accurately blow mold parisons other than the shape of a dogleg curved pipe that is convex in the forward direction.

Said Japanese Patent Publication No. 61-32128 and Japanese Patent Application Laid-Open No. 61-1989
In place of the air suction hole in the mold in JP-A No. 179718, in the device of JP-A-60-18328,
A pin for regulating the position of the parison is provided in the cavity of the lower mold, in which the wall thickness of the hollow molded product having a curved part is to be made uniform, so that it can be retracted from the cavity according to the mold alignment operation of the upper and lower molds. Interlocking means for retracting this pin from the cavity of the lower mold during blow molding each time the molds are matched is built into the lower mold, which complicates the structure of the lower mold and leaves room for improvement. ing.

<Means for solving the problem> This invention solves the above problem by a simple means. In the parison supply device that supplies the parison into the cavity, a plurality of fixing pins are implanted on the mating surface of the lower mold along the outer periphery outside one edge of the cavity provided in the lower mold. A hole is drilled in the mold matching surface to receive the fixing pin, and the parison supply mechanism is attached to the machine frame so that it can move forward and retreat toward these fixing pins from the side mold on the side where the fixing pin is not installed. This parison supply mechanism has a
The parison supply device is characterized in that a pressing member is detachably provided, the front surface facing the fixing pin and having a pressing surface formed to match the shape of the outer edge of the cavity of the lower mold.

<Function> The function of the present parison supply device configured as described above will be described below.

With the upper and lower matching molds open, the parison that has been manually or mechanically fed to the front of the pressing member of the parison supply mechanism is transferred toward the cavity of the lower mold by the forward movement of this pressing member, and finally The parison is pressed against the fixing pin, and its pressing surface deforms the parison following the planar shape of the cavity, and the parison thus deformed following the molding is supplied and stored into the cavity. Next, after retracting the pressing member, the upper mold is aligned with the lower mold, and with this fixing pin inserted into the above-mentioned escape hole of the upper mold, blow molding is performed as usual, and the parison is straightened into a predetermined shape. Manufactured into pipes and bent pipes.

When manufacturing a tube of a different shape, the pressing member is removed from the parison supply mechanism, and the pressing member is then provided with a pressing surface that matches the shape of the tube to be manufactured, that is, the shape of the outer edge of the cavity of the lower mold for forming the tube. The pressing member is replaced with another pressing member, and the parison is supplied and stored into the cavity of the lower mold in the same manner as described above.

<Effects> The present parison supply device configured and operated as described above has the following effects.

A plurality of fixing pins are implanted on the mating surface of the lower mold along the outer peripheral edge outside one edge of the cavity of the lower mold, and the pressing member that transfers the parison toward the fixing pins is supplied to the parison. Attached to the mechanism,
The front surface of this pressing member is formed into a pressing surface that matches the outer edge shape of the cavity of the lower mold, so the parison is pressed against the fixing pin by the forward force of the pressing member, and the cavity of the lower mold is mechanically pressed. The parison can be deformed to follow the shape, and by inserting the fixing pin into the hole in the upper mold without retracting it when the upper mold and lower mold are combined, this parison can be continuously blow molded, and the lower mold can be deformed. The parison can be fed into the cavity of the lower mold without complicating the structure, and
The parison can be shaped into various cavity shapes such as a letter or a W-shape.

<Example> A typical example of the feeding device of the present invention will be described based on the drawings together with the preceding conveyance device.

In FIGS. 1 and 2, A is an extruder,
Below the downward fixed die 10 of this extruder A,
A conveying table 20 with a built-in heater is a type of parison conveying device that receives and horizontally supports the parison P extruded downward from the die head 10.
is installed in the machine frame 11 so that it can be horizontally reciprocated between the bottom of the die head 10 and the lower mold 30.

Reference numeral B designates the present parison supplying device, and a pressing member 40 detachably attached to this supplying mechanism is driven by a fluid pressure cylinder device C, which is a driving device, in a direction perpendicular to the moving direction of the conveyance table 20. The transport table 2 is movable horizontally along the upper surfaces of the transport table 20 and the lower mold 30 from the horizontal upper surface of the transport table 20 to the position of the cavity 31 of the lower mold 30 adjacent thereto.
It is installed in the machine frame 11 at a forward position of 0 in the forward direction.

Cavity 3 of the lower mold 30 on the side opposite to the side where this conveyance table 20 contacts the lower mold 30
A plurality of fixing pins 32 for parison bending are installed vertically along the outer peripheral edge of the mold 1 and on the upper surface of the lower mold 30 on the outside of the cavity 31. The fixing pin 32 is disposed only on the outer peripheral edge of the cavity 31 which is two-dimensionally bent within a horizontal plane convex toward the front surface of the cavity 40.

Escape holes 33 for these fixing pins 32 are bored in the mating surfaces of the lower mold 30 and the paired upper mold 34.

The front surface of the pressing member 40 is a pressing surface 41 that faces the fixing pin 32 and is formed to match the shape of the outer peripheral edge of the cavity 31 of the lower mold 30.

A cutter 50 is provided near the die head 10, which is placed on the conveying table 20 and seals and cuts the end of the parison P that is connected to the die head 10.

At the position where the upper and lower molds 30 and 34 are aligned, a pressurized air injection needle 60 that pierces the air-filled parison P _p in the cavity 30 from one end thereof is attached to the machine frame 11 so that it can move forward and backward with respect to the upper and lower molds 30 and 34. It is provided in

In order to manufacture a bent tube that is two-dimensionally bent in a horizontal plane using the parison conveying table 20 and the present supply device B, first, the tip of the parison P that is extruded downward from the die head 10 is moved to the conveying table. 20, and the parison P is horizontally conveyed in the direction of the pressing member 40 by the forward movement of the conveyance table 20. Immediately after the start of this conveyance, the tip of this parison P is cut by the cutter 50.
Seal with. Thereafter, while the conveyance table 20 is moving forward, pressurized air is continued to be fed into the parison P from the die head 10, and the parison P pushed out and placed on the conveyance table 20 is heated by the heater embedded in the conveyance table 20. The lower surface is heated, the lower surface is prevented from cooling earlier than the upper surface, and the entire shape of the parison P is maintained in a cylindrical shape.
The conveyance table 20 is pushed out from the die head 10.
When the length of the parison P placed above reaches a predetermined length, the parison P is hermetically cut near the die head 10 by the cutter 50 to form an air-filled parison P _p with both ends closed.

This parison P _p is further fed forward by the conveying table 20, and with the parison P p being fed into the front surface of the pressing member 40, the conveying table 20 is stopped at this position. Next, the pressing member 40 is moved to this conveyance table 2.
0 along the upper surface toward the lower mold 30, and simultaneously supplies the air-filled parison P _p onto the cavity 31 of the lower mold 30 with the upper mold 34 raised and separated, and at the same time presses the air by the pressing surface 41. Press the enclosed parison P _p against the fixing pin 32 and press the lower mold 3
It is deformed following the planar contour shape of the cavity 31 of No. 0.

At this time, the pressure air filling needle 60 is inserted into the lower mold 30.
an air-filled parison located within the cavity 32 of the
Poke one end _of this air-filled parison P _p
By supplying pressurized air into the mold, a parison P _p completely filled with air is preformed so as to be in close contact with the inner surface of the cavity 31 of the lower mold 30.

Next, the pressing member 40 is retreated to the outside of the lower mold 30, and the transport table 20 is retreated to return to its original position, and the upper mold 34 is aligned with the lower mold 30, and the parison stored in the cavity 31 as usual. By blow molding P _p , a desired bent hollow tube having the cavity shape of the upper and lower molds 30, 34 is manufactured without a parison cutting process.

The bent hollow tube manufactured in this way is placed in the upper and lower molds 3.
0.34, its closed ends are cut off as necessary, and the duct is used, for example, as a duct for automobile air conditioning.

Next, when blow molding a bent pipe with a different shape, the upper and lower molds are of course replaced, and the pressing member 40 is removed from the supply mechanism and replaced with another suitable one that corresponds to the replaced mold. .

<Effects specific to the embodiment> A manufacturing apparatus in which the fixing pin 32 is implanted in the matching surface of the lower mold 30 only along the outer peripheral edge portion of the cavity 31 that is convex with respect to the pressing member 40. In this embodiment, a two-dimensional bent tube can be accurately manufactured using a small number of fixing pins 32.

In an embodiment in which a parison of a predetermined length with both ends closed in advance is supplied to the lower mold 30, the upper and lower molds 3
During blow molding within the molds 30 and 34, it is not necessary to provide the upper and lower molds 30 and 34 with a structure for cutting and sealing both ends of the parison as in the conventional example.

In the description of the above embodiment, the conveyance table 20 for receiving the parison P from the extrusion molding machine A was also used.
Even if the parison P is directly supplied from the extrusion molding machine A to the flat upper surface outside the cavity of the mold in front of the pressing member 40, the invention is the same.

Furthermore, in the case of manufacturing a three-dimensionally bent bent tube, the parison conveying table 20 may be, for example, a parison conveying table 20 whose upper surface is formed into a shape corresponding to the bent shape projected onto the vertical plane of the bent tube. The pressing surface 41 of the pressing member 40 is formed into a shape that matches the bent shape of the bent pipe projected onto the horizontal plane.

Using such a parison conveying table 20 and pressing member 40, a three-dimensionally bent bent tube can be manufactured in the same manner as described above.

When the heater is embedded in the conveyance table 20 as described above, the lower mold 30 is removed from the die head 10.
The entire parison P _p can be heated to a uniform temperature during transportation to the lower mold 30 side, with the parison P _p maintaining its _cylindrical shape without uneven thickness or wrinkles and without deformation. This cylindrical parison P _p can be inserted into the cavity 31 of the lower mold 30 all at once, and the contact cooling time between the lower mold 30 and the parison P _p can be made uniform over the entire length of the parison P _p . Mold 30
It can be used only for cooling and fixing parison _P , improving product production efficiency.

[Brief explanation of the drawing]

The figures relate to this invention; Fig. 1 is a schematic front view showing the relationship between the pressing member, the lower mold, and the conveyance table in a feeding device that is a typical embodiment of the invention, and Fig. 2 is a plan view thereof. , and FIG. 3 are schematic front views showing the relationship between the fixed die head of the extruder and the conveyance table. Explanation of main symbols in the figure, 10...Fixed die head, 20...Transport table, 30...Lower mold, 3
...fixing pin, 40...pressing member, B...supply device.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. In a parison feeding device that supplies a parison extruded from an extruder into a cavity of a lower mold of upper and lower molds, the mating surface of the lower mold has a lower mold. A plurality of fixing pins are implanted along the outer peripheral edge outside one side edge of the cavity provided in the mold, and holes are bored in the upper mold mating surface to receive the fixing pins. A parison supply mechanism is provided on the machine frame so as to be able to move forward and retreat toward the fixing pin from the side on which the fixing pin is not installed. A parison supply device characterized in that a pressing member having a pressing surface formed to match the outer edge shape of a cavity of a lower mold is detachably provided. 2. The parison feeding device according to claim 1, wherein the cavity is bent in two or three dimensions. 3. The parison feeding device according to claim 1, wherein the fixing pin is implanted in the mating surface of the lower mold only along the outer peripheral edge of the cavity that is convex with respect to the pressing member. 4. The parison feeding device according to claim 1, wherein the parison is a parison of a predetermined length with both ends closed in advance.