JPH0661826B2 - Parison generator - Google Patents

Description

Description: TECHNICAL FIELD The present invention generally relates to a parison generator used in a hollow molding device or the like, and more specifically, it switches a plurality of different resins from the same head outlet. The present invention relates to a parison generator capable of generating a parison whose material is changed in the longitudinal direction by discharging the parison.

2. Description of the Related Art Conventionally, hollow molded articles are formed from the same resin material, and therefore the characteristics of the hollow molded article are uniquely determined according to the characteristics of the material, for example, hard material or soft material. It had been. Therefore, in order to make one part of the molded article have different characteristics from other parts,
It was necessary to separately mold the respective parts by different molding processes, and to bond the separate molded products together, for example, with an adhesive or the like. Such a conventional technique not only complicates the manufacturing processor, but also has a problem in strength in the final product, and an improvement has been desired.

Aim The present invention has been made in view of the above points, and solves the above-mentioned drawbacks of the prior art and forms a parison of different materials in the longitudinal direction by selectively supplying different resin materials. An object of the present invention is to provide a parison generator that can be used.

Structure According to the present invention, paths for receiving respective resins are formed in the head to which two or more different resins are supplied, and those paths are selectively communicated with the outlet of the head. Provided is a parison generating device capable of generating a parison of different kinds in the longitudinal direction by providing a selective communication means and selectively switching a plurality of resins to feed to the head outlet. In this case, in a preferred embodiment, an annular working chamber is formed in the head, and a floating ring serving as a selective communication means is movably provided in the working chamber, and the floating ring is moved depending on the position of the floating ring in the working chamber. Each of the paths is selectively communicated with the head outlet.

According to another aspect of the present invention, a plurality of paths are provided in the head so that two or more kinds of different resins can be selectively supplied to the head outlet, and the paths are connected to the respective paths. Is provided, and suction means is provided so as to be connectable to each branch path,
When the resin is switched to the head outlet by switching from one certain path to another path, the path supplying the resin until then is sucked and the resin is sucked to the branch path connected to it. It enables sharp switching of resin in the longitudinal direction of the parison.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a cross section of a plastic molded product 1 that can be manufactured by applying the device of the present invention. The plastic product 1 shown in FIG. 1 has a pair of cylindrical portions 1a, 1a, and a bellows portion 1b extending between them by connecting them. Such a plastic product 1 is used, for example, as a part of a duct of an air conditioner, and its cylindrical portion is connected to a predetermined device for flowing a refrigerant or other fluid. In this case, the bellows portion 1b is provided to bend or absorb vibrations, and therefore, it is required that its characteristics have elasticity or flexibility, while the cylindrical portion is provided with the device. Since it is connected to the duct system, it is required to be formed from a relatively hard resin material.
As described above, when a portion having different characteristics in the longitudinal axis direction of the plastic product 1 is required, it is necessary to change the material, and in that case, in the conventional technique, the bellows portion 1b and the cylindrical portion 1a are required. And were separately blow molded, that is, blow molded, and they were integrated by using an adhesive or the like.

According to the present invention, as shown in FIG. 1, it is possible to easily form hollow products having different properties in the longitudinal direction, that is, different materials made of different materials, by a single process by blow molding. That is, the parison generator of the present invention can generate a parison in which two or more kinds of resin materials are switched in the longitudinal axis direction, and such a parison is put into a desired mold and blown. Thus, it is possible to easily perform blow molding.

FIG. 2 shows a parison generator constructed according to one embodiment of the present invention and applied to a blow molding machine, which is generally a head 10 and a first resin 24.
It has a first feeder 20 for feeding to the head 10 and a second feeder 30 for feeding the second resin 34 to the head 10. The head 10 includes a substantially cylindrical inner die 11 and an inner die 11
And an external die 12 for externally inserting. A center hole 11a is provided through the inner die 11, and the upper end of the center hole 11a is connected to a pressurized air source 41.

In the head 10, it is connected to the first feeder 20 and
A first path 15 for receiving a first resin supplied from the first path 15 is formed. The first path 15 is formed in the head 10 between the inner die 11 and the outer die 12 in an annular shape to form a switching working chamber. It is connected to 14. In the case of the illustrated example, the first path is connected to the bottom of the annular working chamber 14. A branch path 15a is provided so as to communicate with the first path 15 and extends for a predetermined distance, and a valve 18 is provided at the tip of the branch path. The working chamber 14 has a predetermined axial length, and a common discharge path 17 is provided so as to be connected to an intermediate portion thereof, and the common path 17 is the head 1.
Outlet 10 for discharging the parison 44 formed at the lower end of 0
It extends to b. The second path 13 is connected to the upper end of the working chamber 14, and the second path 13 extends upward between the inner soybean 11 and the outer die 12, and in the illustrated example, the right direction. And is connected to the second feeder 30.

A floating ring 16 is disposed in the working chamber 14, and the floating ring 16 is slidably movable along the axial direction of the annular working chamber 14. When the floating ring 16 is located in the lowered position as shown in FIG. 2, the communication between the first path 15 and the working chamber 14 is blocked, and the first resin 24 is blocked by the first resin 24.
To be supplied to. On the other hand, when the floating ring 16 is located at the raised position of the working chamber 14, the second path 1
The communication between 3 and the working chamber 14 is blocked, and the first path 15 and the common path 17 are brought into the communicating state via the working chamber 14. In this way, the first path 15 and the second path 13 are selectively communicated with the common path 17 via the working chamber 14 depending on whether the floating ring 16 is in the raised position or the lowered position. As will be described later, in the present embodiment, the floating ring 16 is automatically moved to the respective raised or lowered positions by utilizing the supply pressure of the supplied resin. A second branch path 13a is provided so as to communicate with the second path 13, and a valve 19 is provided at the tip of the second branch path 13a.

The first feeder 20 and the second feeder 30 have basically the same configuration, and therefore only the configuration of the first feeder 20 will be described in detail here. It should be noted that the parts of the second feeder 30 corresponding to the first feeder 20 are replaced by 30 instead of 20's.
The reference number of the place of is attached. The first feeder 20 includes a guide 21 having a supply path 21a formed therein and a path 21a.
And a screw 22 disposed therein. The supply path 21a communicates with the first path 15 of the head 10 via a flow rate adjusting valve 23. Therefore, the first molten state
The resin 24 is supplied by the first feeder 20 into the first path 15 of the head via the valve 23. On the other hand, the melted second resin 34 is supplied to the second path 13 of the head 10 by the second feeder 30 via the flow rate adjusting valve 33. The valves 18 and 19 for depressurizing and the valves 23 and 33 for adjusting the flow rate of the resin are connected to the control device 42 and selectively operated under the control of the control device 42.

The operation of the second parison generator having the above configuration will be described. First, the second feeder 30 is held in a stopped state, the screw 22 of the first feeder 20 is driven to rotate, and the first resin 24 is passed through the valve 23 to the first resin of the head 10.
Supply to the route 15. Then, under this supply pressure, the floating ring 16 is pushed upward along the axial direction of the annular working chamber 14 and is positioned at its raised position. Therefore, when the second path 13 is closed by the floating ring 16, the first path 15 is connected to the common path 17 via the working chamber 14. Therefore, only the first resin 24 supplied from the first feeder 20 is discharged through the outlet 10b of the head to form the first resin portion 24 'of the parison 44. Then, the first feeder 20 is stopped, and the screw 32 of the second feeder 30 is driven and rotated to move the second feeder 30.
The supply of the second resin 34 from the feeder 30 to the head 10 is started. In this case, the pressure release valve 18 is opened at the same time. Therefore, since the second resin 34 is supplied from the second feeder 30 into the second path 13, due to the supply pressure,
The floating ring 16 is pressed against the lower end of the working chamber 14. In this case, since the valve 18 of the first branch path 15a is opened, the first resin 24 in the first path 15 is partially moved into the first branch path 15a, so that the floating ring 16 is largely removed. It is located at the bottom of the working chamber 16 without any resistance. This state is shown in FIG. 2, and in this state, the first path 15 is closed by the floating ring 16, and the second path 13 is connected to the common path 17 via the working chamber 14. Therefore, the second resin 34 supplied from the second supplier 30 via the valve 33 is discharged from the outlet 10 b via the second path 13, the working chamber 14, and the supply path 17, and the second resin portion 34 of the parison 44. ′ Is formed.

In this case, in the present embodiment, the floating ring 16 is automatically positioned in the upper and lower positions selectively by the supply pressures of the resins 24 and 34, respectively, and closes the path through which the resin was previously supplied. Therefore, the switching point 44 of the material of the parison
a can be relatively sharp.
Although the floating ring 16 is used in the above-described embodiment, it is also possible to use a ball, a rod, or the like to switch the path.

Next, FIG. 3 shows a case where a parison generator constructed according to another embodiment of the present invention is applied to a blow molding machine. In the present embodiment, constituent elements corresponding to those of the embodiment of FIG. 2 are designated by corresponding reference numerals. Also in the parison generator of FIG. 3, the head 10 is generally used.
The first supply device 20 and the second supply device 30 are provided. In this embodiment, the first path 15 formed in the head 10 extends from the first feeder 20 to the outlet 10b which is the ejection port of the head 10 and also from the second feeder 30. The second path 13 also extends between the inner soybean 11 and the outer soybean 12 to the outlet 10b of the head 10. Therefore, the first path 15 and the second path 13 are connected in the vicinity of the outlet 10b of the head 10.

In the embodiment of FIG. 3, a first suction device 45 is provided at the tip of the first branch path 15a branching from the first path 15 via the pressure relief valve 18. Similarly, a second suction device 46 is provided at the tip of the second branch path 13 a branching from the second path 13 via the pressure relief valve 19. These suction devices 45 and 46 are connected to a suction control device 47. As a modification, a single suction device may be provided and selectively connected to the first branch path 15a and the second branch path 13a. The other structure is substantially the same as that of the embodiment shown in FIG.

Next, the operation of the embodiment shown in FIG. 3 will be described.
First, the first feeder 20 is maintained in a stopped state, the screw 32 of the second feeder 30 is driven and rotated, and the second resin 34
Is supplied to the second path 13 via the valve 33 for adjusting the flow rate. Therefore, the second resin 34 is discharged from the outlet 10 of the head 10.
The second resin portion 34 'of the parison 44 is discharged through b.
To form. After discharging a predetermined amount of the second resin, the second feeder 30 is stopped and the screw 22 of the first feeder 20 is driven and rotated. Therefore, the first resin 24 is supplied into the first path 15 of the head 12 via the valve 23. In this case, the depressurization valve 19 is opened to the atmosphere for a certain period of time immediately before or after driving the screw 22 of the first feeder 20. As a result, the pressure in the second path 13 is reduced, so that only the first resin 24 is discharged from the outlet 10 of the head 10.
It is possible to ensure that the second resin 34 is discharged from b, and the second resin 34 is held in the second path 13. Therefore, the second resin 34 is not caught and discharged from the outlet 10b. As a modified example, it is possible to open the depressurization valve 19 and operate the second suction device 46 to forcibly suck the second resin 34 toward the second branch path 13a for a predetermined time.

As described above, also in this embodiment, the material of the parison 44 discharged from the head 10 can be switched along the longitudinal axis thereof, and the switching point 44a can be sharpened. is there.

Effects As described above in detail, according to the present invention, it is possible to generate a parison whose material is sharply switched in the longitudinal direction. According to one feature of the present invention, a switching operation chamber is formed in the head, and an operation member such as a floating ring is movably provided in the operation chamber, and a predetermined position is automatically set by the supply pressure of the resin supplied to the head. The resin switching operation is ensured by moving to. On the other hand, according to another feature of the present invention, a plurality of paths extending to a common outlet are provided in the head, and the paths are appropriately opened to the atmosphere or sucked to perform sharp resin switching. Is possible. In this case, the head itself can be downsized.

The specific embodiments of the present invention have been described above in detail, but the present invention should not be limited to these specific examples, and various modifications can be made without departing from the technical scope of the present invention. Of course, it is possible.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a plastic product suitable for manufacturing according to the present invention, and FIG. 2 is a blow molding machine to which a parison generator constructed according to one embodiment of the present invention is applied. FIG. 3 is a schematic diagram showing a case, and FIG. 3 is a schematic diagram showing a case in which a parison generator configured according to another embodiment of the present invention is applied to a blow molding machine. (Explanation of reference numerals) 10: Head 13: Second path 14: Working chamber 15: First path 16: Floating ring 17: Common path 18, 19: Pressure release valve 20: First feeder 23, 33: Flow control valve 30: Second feeder 44: Parison 45, 46: Suction device

Claims (4)

[Claims] 1. A first supply unit for supplying a first resin, a second supply unit for supplying a second resin, and the first and second units.
A head that forms a parison by discharging the first and second resins received from the supply means from the outlet, and the head is provided with the first resin received from the first supply means. A first path for supplying the second resin to the head outlet and a second path for supplying the second resin received from the second supplying means to the head outlet.
Selective communication means for selectively communicating a path to the head outlet is provided, first and second valves are provided so as to communicate with the first and second paths, respectively, and the first and second valves are provided. The parison generator, wherein the pressures in the first and second paths are released according to the switching of the resin. 2. The method according to claim 1, wherein
And the second path is connected midway and extends from the connecting part to the head outlet via a common path, a working chamber is formed in the connecting part, and the selective communication means is provided in the working chamber. The movable body is movably disposed, and when the movable body is located at the first position in the working chamber, the first path is communicated with the head outlet, while the movable body is located at the second position. The parison generating device is characterized in that the second path is communicated with the head outlet. 3. The working chamber according to claim 2, wherein the working chamber has a substantially annular shape, and the working body is a floating ring and is movably arranged in the annular working chamber. A parison generating device characterized in that the floating ring is automatically positioned at the first and second positions by the supply pressures of the first and second resins supplied from the first and second supply means, respectively. . 4. A first supply unit for supplying a first resin, a second supply unit for supplying a second resin, and the first and second units.
A head for discharging the first and second resins received from the supply means from an outlet to form a parison, and a first path for supplying the first resin received from the first supply means to the head outlet; The second received from the second supply means
Provided with a second path for supplying the resin to the head outlet, first and second branch paths provided in communication with the first and second paths, respectively, and the first and second paths. Two
A suction means capable of communicating with the branch passage,
A parison generator, wherein the corresponding suction means sucks the corresponding resin into the first or second branch when the second resin is switched.