JP2001294431A - Parison molding method and parison molding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the adhesion of foreign matter, etc., to the inside surface of a parison without degrading productivity. SOLUTION: This device has a parison molding mechanism 4 which molds the parison 3 by advancing a plunger 9 into a melding die 5 fed with a gob 2 and a cooling device 30 for cooling the plunger 9 by introducing air into the parison 3. The inside of the plunger 9 is communicated with an air introducing path P for introducing the air for cooling and an air leading-out path Q for leading out the air after the cooling to the outside. The air leading-out path Q is communicated with an exhaust device 50 which exhausts the air after the cooling by acting suction force on the air leading-out path Q.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a parison molding method for molding a parison by injecting a plunger into a molding die into which a gob has been put, and a parison molding apparatus used for carrying out the method.

[0002]

2. Description of the Related Art A glass bottle manufacturing process includes a parison forming process for forming an intermediate molded product called "parison". In this parison forming step, a molten glass called “gob” is guided into a forming die, and a plunger is inserted into the forming die from a tip portion to press the gob to form the parison.

FIG. 5 shows the configuration of a parison forming mechanism 4 used in the parison forming step. The parison forming mechanism 4 includes a forming die 5, a plunger 9, a plunger driving device 10 for reciprocating the plunger 9, and the like. The mold 5 includes a mouth 7 for molding the mouth of the parison 3, a rough mold 6 for molding the body of the parison 3, and a baffle 8 for molding the bottom of the parison 3. The plunger 9 is a hollow body that is thinner toward the front, and the base end is formed in a cylindrical shape.

The plunger drive 10 includes a cylinder 11
And a hollow piston rod 12 is protruded from the piston 15. The proximal end of the plunger 9 is connected to the distal end of the piston rod 12 by a plunger holding mechanism 20. The plunger holding mechanism 20 includes a cylindrical adapter 21 and a connecting ring 23, and between the adapter 21 and the connecting ring 23, cooling air after cooling the plunger 9 is exhausted from the hollow portion 9 </ b> A of the plunger 9. For this purpose, the exhaust passage 22 is provided at an equiangular position in the circumferential direction.

In the illustrated example, an air cylinder is used as the cylinder 11, but a hydraulic cylinder can also be used.
Further, a servomotor can be used instead of the cylinder. By supplying compressed air to the first chamber 13 inside the cylinder 11, the piston rod 12 moves up together with the piston 15. When the plunger 9 reaches the upper limit position, the plunger 9 goes deeply into the mold 5. Further, by supplying compressed air to the second chamber 14 of the cylinder 11 and evacuating the first chamber 13, the piston rod 12 descends, and the plunger 9 withdraws from the molding die 5.

[0006] At the tip of the piston rod 12, a pipe 16 for introducing cooling air is connected. This introduction pipe 16
Has a nozzle 16a for guiding the cooling air to near the tip of the plunger 9. An air supply pipe 35 vertically passes through the inside of the cylinder 11, and the upper end of the air supply pipe 35 communicates with the hollow portion 12 </ b> A of the piston rod 12. The inner hole of the air supply pipe 35 and the hollow portion 12A of the piston rod 12 form an air introduction path P for guiding cooling air into the plunger 9.

A plunger positioner 18 is located above the cylinder 11. Inside the plunger positioner 18, a cylindrical plunger guide 19 for supporting the plunger 9 so as to be able to reciprocate, and a spring 25 for supporting the plunger guide 19 in a state of being biased in the direction of the molding die 5 are provided. When the plunger 9 is pulled out of the parison 3 after the parison 3 is formed, the plunger guide 19
5 is pushed down against the spring force of 5.

The inside of the plunger guide 19 communicates with the inside of the plunger 9 through the exhaust passage 22. An opening 19 a is formed at the lower end of the plunger guide 19, and an air passage 36 is formed inside the cylinder wall 11 a of the cylinder 11.
Are formed respectively. The air passage 36 communicates with the inside of the plunger guide 19 through the opening 19a. The air passage 36 and each part communicating with the air passage 36 constitute an air outlet passage Q for exhausting cooling air (hereinafter, referred to as “exhaust air”) after cooling the plunger 9.

FIGS. 6 (1) to 6 (3) show an outline of a molding process of the parison 3. FIG. Mold 5 in position to receive gob 2
Is set, the rough die 6 is set on the die 7, and the tip of the plunger 9 is positioned near the die 7. Next, after the gob 2 is introduced from the upper end opening of the rough mold 6, the baffle 8 is set so as to close the upper opening of the rough mold 6 (FIG. 6 (1)).

After setting the baffle 8, the plunger 9
Is raised, the gob 2 is guided to the gap between the outer peripheral surface of the plunger 9 and the inner surface 5A of the mold. When the tip of the plunger 9 has risen to the upper limit position, the parison 3 is pressurized by the plunger 9 (FIG. 6 (2)). Then, when the gob 2 is guided into the mouth mold 7, the parison 3 as a molded product is formed. After this pressurized state is continued for a certain time,
The molding of the parison 3 ends.

The period during which the tip of the plunger 9 presses the parison 3, that is, FIG.
In the state shown in (2), the cooling air is fed into the hollow portion 9A of the plunger 9 via the air introduction path P to cool the plunger 9. After the exhaust air is exhausted from the exhaust passage 22, the exhaust air is led out of the parison forming mechanism 4 through the above-described air outlet path Q.

When the molding of the parison 3 is completed, FIG.
As shown in (3), the plunger 9 is lowered to the lower limit position, and after the baffle 8 and the rough mold 6 are opened, the parison 3 as a molded product is sent to a finishing process for molding into a final product. .

[0013]

In the parison forming mechanism 4 having the above-described structure, all of the exhaust air must be exhausted to the outside through the air outlet path Q. However, the space between the plunger positioner 18 and the plunger guide 19 is large. In addition, since there is a gap between the plunger guide 19 and the base end of the plunger 9, there is a possibility that the gas leaks to the periphery of the outer periphery of the plunger 9, as shown by a two-dot chain line in FIG. As a result,
Foreign matter D such as metal powder or fine lubricating oil generated by rubbing of the metal member due to sliding of the plunger 9 and the plunger guide 19 is generated around the outer peripheral portion of the plunger 9. When the plunger 9 is pulled out from the inner surface 5A of the mold, a negative pressure is generated in the hollow interior of the parison, and the foreign matter D is drawn into the hollow interior of the parison and adheres to the inner surface of the parison.

The mold inner surface 5A is coated with a release agent such as carbon, and this mold release agent may peel off from the mold inner surface 5A in the process of releasing the parison from the mold inner surface 5A. . The peeled release agent D 'floats around the outer peripheral portion of the plunger 9 and adheres to the outer peripheral surface of the plunger 9, and is pressed against the hollow inner surface of the parison when forming the next parison.

In recent years, there has been a demand for lighter bottles, and bottle manufacturers are producing many thinner bottles. However, the strength of bottles with foreign substances and mold release agents attached to the inner surface decreases, There is a risk of rupture due to contact between bottles, an increase in internal pressure in the bottle, thermal shock, and the like. Therefore, a method has been implemented in which the pressure of the cooling air for cooling the plunger is set to a low pressure so that foreign substances and the like are not drawn into the hollow interior of the parison.

However, the above-described method cannot completely prevent foreign substances from being drawn into the hollow interior of the parison, and also causes a decrease in production capacity. Therefore, this method is applied to mass production of bottles. It is difficult.

The present invention has been made in view of the above problems, and provides a parison molding method and a parison molding apparatus which prevent foreign substances from adhering to the inner surface of a parison without reducing productivity. With the goal.

[0018]

According to the present invention, air is introduced into the plunger to cool the plunger when the parison is formed by injecting the plunger into the molding die into which the gob is inserted. In the parison molding method, the air after cooling is exhausted by applying a suction force to an air outlet path from the plunger.

A parison forming apparatus according to a second aspect of the present invention is a parison forming mechanism for forming a parison by injecting a plunger into a forming die into which a gob is inserted, and introducing a plunger by introducing air into the plunger. A cooling device for cooling. The inside of the plunger is communicated with an air introduction passage for introducing air for cooling and an air outlet passage for introducing the cooled air to the outside. The air outlet passage communicates with an exhaust device that exhausts the cooled air by applying a suction force to the air outlet passage.

[0020]

[Function] The air after cooling the plunger is exhausted through the air outlet path. However, since the suction force is applied to the air outlet path, foreign matters and the like generated in the parison forming mechanism are removed together with the cooled air. It is led to the air outlet.

[0021]

FIG. 1 shows the configuration of a parison molding apparatus according to one embodiment of the present invention. The parison molding device in the illustrated example is:
A parison forming mechanism 4 for forming the parison 3 by injecting the plunger 9 into the forming die 5 into which the gob 2 is inserted, and a cooling device 30 for introducing cooling air into the plunger 9 to cool the plunger 9 are provided. .

The parison forming mechanism 4 has the same structure as that of the conventional example shown in FIG. 5, and has an air introduction passage P for introducing cooling air and an air outlet passage Q for introducing exhaust air to the outside. And The inside of the plunger 9 communicates with the air introduction passage P and the air outlet passage Q. In the air outlet path Q,
An exhaust device 50 that exhausts exhaust air by applying a suction force to the air outlet path Q is communicated. Since the parison forming mechanism 4 has the same configuration as that of the conventional example in FIG. 5, the detailed description is omitted by attaching the same reference numerals to the corresponding components.

The air introduction passage P has a manifold 33
The cooling air is supplied through the air supply pipe 38. An operating valve 32 is interposed in the middle of the air supply pipe 38. The operating valve 32 is opened and closed by an operating valve drive mechanism 31. When the operating valve 32 is opened, cooling air is introduced from the manifold 33 into the air introduction passage P through the air supply pipe 38.

The cooling air is sent to the introduction pipe 16 through the air introduction path P, and is guided to near the tip of the plunger 9 by the nozzle 16a of the cooling air introduction pipe 16 as shown in FIG. A plurality of ventilation holes 16c are opened at the tip of the nozzle portion 16a, and cooling air is supplied to each of the ventilation holes 1c.
It is fed into the hollow part 9A of the plunger 9 from 6c. The cooling air after cooling the plunger 9 becomes exhaust air and is discharged from the exhaust passage 22. The exhaust passage 22 communicates with the exhaust port 37 via the air outlet path Q.

FIG. 3 shows an example of the configuration of the exhaust device 50 connected to each exhaust port 37 of the plurality of parison forming mechanisms 4. The exhaust device 50 of this embodiment includes a blower 51, an exhaust pipe 57A having bifurcated branch pipes 57B and 57C, and a plurality of communication pipes 57D communicating with one of the branch pipes 57B and 57C.
It is composed of When the blower 51 is driven, the exhaust pipe 57
A, suction force acts on the air outlet paths Q of the plurality of parison forming mechanisms 4 via A, the branch pipes 57B and 57C, and the communication pipes 57D, and the exhaust air is guided from each parison forming mechanism 4 to the exhaust device 50.

In the blower 51, the number of revolutions of the motor is controlled by an inverter 52. The exhaust pipe 57A is provided with an on-off valve 53 that is manually opened and closed. The suction force applied to the air outlet path Q of each parison forming mechanism 4 can be adjusted by controlling the drive of the blower 51 by the inverter 52 and controlling the opening of the on-off valve 53.
The magnitude of the suction force is set to an optimal value corresponding to the pressure of the exhaust air exhausted from the parison forming mechanism 4. If this suction force is set to be lower than the pressure of the exhaust air, it is impossible to exhaust foreign substances and the like near the outer peripheral portion of the plunger 9 together with the exhaust air. On the other hand, if the pressure is set higher than the pressure of the exhaust air, foreign matter floating outside the parison forming mechanism 4 will be drawn.

Each communication pipe 57D is provided with a butterfly valve 61 which is opened and closed by a valve drive mechanism 60. Each valve drive mechanism 60 opens the butterfly valve 61 in accordance with the timing of introducing air into the plunger 9 of each parison forming mechanism 4, whereby the communication pipe 57 </ b> D is opened and the suction force of the blower 51 is opened. Acts on the parison forming mechanism 4.

Each communication pipe 57D is provided with a pressure gauge 54 for measuring a suction force, an adjustment valve 55 for adjusting the suction force, and a natural exhaust port 56B and a filter 59. The suction force of the blower 51 is
Since there is a difference depending on the distance of each communication pipe 57D with respect to 1, the adjustment valve 55 is adjusted while checking the pressure gauge 54 to make the suction force acting on each communication pipe 57D constant.

Each natural exhaust port 56B is provided with a regulating valve 55.
Is closed to check the pressure of the exhaust air naturally exhausted from the parison forming mechanism 4 and to open the exhaust air naturally exhausted from the parison forming mechanism 4 through the communication pipe 57D. The filter 59 is provided to remove foreign matter discharged from the parison forming mechanism 4 together with the exhaust air.

The branch pipes 57B and 57C are also provided with a natural exhaust port 56A. These natural exhaust ports 56A
When the parison is formed by stopping the blower 51,
It is opened when the exhaust air naturally exhausted from each parison forming mechanism 4 is exhausted from the branch pipes 57B and 57C.

FIG. 4 is a view showing a position where the plunger 9 moves up and down,
The relationship between the timing of supplying and stopping the cooling air and the timing of applying a suction force to the parison forming mechanism 4 is shown. The position of the plunger 9 is determined by the reciprocating operation of the cylinder 11. The timing of supplying and stopping the cooling air is determined by the operation valve 32 of the cooling device 30.
The timing at which a suction force is applied to the parison forming mechanism 4 by the opening / closing operation is determined by the opening / closing operation of the butterfly valve 61 of the exhaust device 50. In this embodiment, the blower 51 of the exhaust device 50 is operated continuously.

Now, before the gob injection, the plunger 9
Rises from the lower limit position to the gob throwing position, the butterfly valve 61 opens at time T1, and the suction force by the exhaust device 50 acts on the parison forming mechanism 4. Butterfly valve 61
The cooling device 30 starts supplying the cooling air with a delay of the predetermined time α1 from the opening operation of the cooling device 30. On the other hand, plunger 9
Starts rising after the gob is supplied and before the cooling air is supplied. Here, the reason why the suction force is applied prior to the supply of the cooling air and the rising operation of the plunger 9 is to remove foreign matters and the like remaining in the parison forming mechanism 4 to the air outlet path Q.

The supply of the cooling air is continued for a time period TA immediately before the plunger 9 reaches the upper limit position and immediately after the lowering start, and the suction force is continuously applied to the parison forming mechanism 4. The supply of the cooling air is stopped immediately after the plunger 9 starts lowering, and when the plunger 9 is lowered to the lower limit position at a time T2 delayed by a predetermined time α2, the butterfly valve 61 closes and the parison forming mechanism 4 Stop the action of the suction force. Here, the reason why the suction force is applied even when the supply of the cooling air and the lowering of the plunger 9 are finished is that foreign matters and the like remaining in the parison forming mechanism 4 are removed by the negative pressure generated by the lowering of the plunger 9. This is to keep them out of the parison.

When the plunger 9 is lowered to the lower limit position, the rough mold 6 is opened, and the parison 3 held by the mouth mold 7 is transferred to the finishing mold together with the mouth mold 7. After the parison 3 is delivered to the finishing mold, when the mouth mold 7 is returned to the rough mold 6, the plunger 9 is raised to the gob charging position, the gob is charged, and the parison molding is restarted.

If the temperature of the plunger 9 rises excessively, or if the temperature of the plunger 9 does not drop easily, the plunger 9 is again at the lower limit position before rising to the gob feeding position. Cooling air for a predetermined time T
Supply only B. In this case as well, at a time T3 preceding the supply of the cooling air by a predetermined time α3, the butterfly valve 61 is opened, a suction force is applied to the parison forming mechanism 4, and a time delayed by a predetermined time α4 from the stop of the supply of the cooling air. T4
To close the butterfly valve 61 to stop the action of the suction force on the parison forming mechanism 4.

In the above embodiment, the suction force to the parison forming mechanism 4 is turned on and off by opening and closing the butterfly valve 61. However, the present invention is not limited to this, and the inverter 52 controls the blower 51 to be turned on and off. May go.

[0037]

According to the present invention, when air is introduced into the plunger to cool the plunger, the air after cooling is discharged by applying a suction force to the air outlet from the plunger. Therefore, the cooled air is reliably guided to the air outlet path and does not stagnate in the parison forming mechanism, and foreign matter and the like can be taken in and removed from the air to be exhausted. As a result, it is possible to prevent foreign substances and the like from being drawn into the hollow interior of the parison, and to solve the problem that foreign substances and the like adhere to the inner surface of the parison and reduce the strength of the bottle.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of a parison molding apparatus according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing a molding die and a plunger during parison molding.

FIG. 3 is a front view showing the entire configuration of the exhaust device.

FIG. 4 is a time chart showing the operation of the parison molding apparatus.

FIG. 5 is a cross-sectional view showing an entire configuration of a conventional parison forming mechanism.

FIG. 6 is a sectional view of the parison forming mechanism showing a parison forming step.

FIG. 7 is an enlarged sectional view of a parison forming mechanism for explaining a conventional problem.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Forming apparatus 2 Gob 3 Parison 4 Parison forming mechanism 5 Mold 9 Plunger 30 Cooling device P Air introduction path Q Air outlet path 50 Exhaust device

Claims (2)

[Claims] 1. A parison molding method in which air is introduced into the plunger to cool the plunger when the plunger enters a molding die into which a gob has been inserted to form a parison. Wherein the air after cooling is exhausted by applying a suction force to the air outlet path of the parison. 2. A parison forming mechanism for forming a parison by injecting a plunger into a forming die into which a gob is inserted;
A cooling device that introduces air into the plunger and cools the plunger, and the inside of the plunger is for introducing air for cooling and introducing air after cooling to the outside. A parison molding apparatus, wherein the air outlet path communicates with an exhaust device that exhausts cooled air by applying a suction force to the air outlet path.