JP2001088204A - Method and apparatus for positioning preform in blow molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To arbitrarily mold a hollow molded article having directionality with intension in blow molding due to a cold parison method and to expand the adaptation range of the pattern/label applied to the molded article and a type of a plug element to enhance commodity value. SOLUTION: In the blow molding of a hollow molded article, a bottomed preform having an engaging part is rotated on its own axis at least at the position immediately before a mold, and a contact member is brought into contact with the engaging part of the preform to stop the rotation of the preform in such a state that the engaging part is turned toward a predetermined direction to position the preform. A preform positioning apparatus has a preform rotating device provided at a front position where the preform is introduced into the mold, and a stop device having the contact member capable of coming into contact with and separating from the engaging part of the preform and stopping the rotation of the preform in such a state that the engaging part of the preform is turned toward the predetermined direction. Since the rotation of the preform can be stopped in a state imparting directionality to the preform, the hollow molded article having directionality can be arbitrarily molded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for positioning a preform in blow molding of a hollow molded product, and more particularly, to introducing a preform into a molding die for blow molding a hollow molded product. A method and an apparatus for positioning a reform in a state where the reform is oriented in a predetermined direction.

[0002]

2. Description of the Related Art Hollow molded articles such as plastic containers and miscellaneous goods stationery are molded by blow molding and widely used. In particular, bottles serving as containers are used for beverages, seasonings, oils, alcohols, cosmetics, detergents, chemicals, and the like.

[0003] In accordance with these uses, various shapes and sizes of bottles, large, medium and small, have been developed and used. As for the shape of the bottle, the cross section of the body is generally round, square, or elliptical, and there are seen those in which various patterns are applied to the surface of the bottle and those in which various labels are attached. Depending on the contents and application, the bottle cap should have a screw cap, a stopper cap, an outer plug (single) type, an inner plug (double) type, a detachable type, a hinge type, and a bottle shoulder. Various plugs such as special types that cover the shape are attached.

[0004] The blow molding method for bottles is roughly classified into a so-called cold parison method and a hot parison method, and the preform (or parison) to be used is also preformed into a bottomed shape by injection molding and extruded. It can be divided into those molded into a cylindrical shape.

[0005] Usually, the shape and capacity of a bottle are selected according to the application, and the pattern, the presence or absence of a label, and the type of plug are determined.
The blow molding method is chosen.

In this case, by optimizing the combination of the shape of the bottle, the pattern / label and the type of the plug, the commercial value is increased and the user is appealed. Therefore, between two or three types of bottle shape, pattern / label, plug type, give directionality so that there is a mutual relationship,
The product value may be increased.

As for the directionality, in relation to the shape of the bottle or the pattern / label and the type of the plug, for example, a hinge type plug is attached to an elliptical bottle, and the finger cover of the hinged cover of the plug is attached to the bottle. A cover that can be opened and closed without changing the bottle by mounting it on the wide side, and a special type that has a horizontal content discharge port on a circular bottle with a pattern on one side. Is mounted such that the contents discharge port is always on the pattern surface side, so that the application surface such as a pattern can be seen when taking out the contents. These bottles
The bottle is formed with directionality so that there is a mutual relationship between the shape of the bottle and the fitting screw of the bottle cap or the plug.

[0008] In such a directional bottle, in the blow molding method by the hot parison method, the injection-molded preform is transferred to the molding die while being sandwiched by the injection molding die, and air is injected into the preform. The molding can be performed by supplying air through a blowing nozzle to blow-mold a hollow molded product in a molding die.

In the blow molding method based on the cold parison method, usually, a preform having a bottom formed by injection molding is cooled to room temperature, heated and softened in the next step, and then the preform is placed in a molding die. Then, air is supplied into the preform, and the hollow molded article is blow-molded in a molding die to be molded. However, when a preform is introduced into a molding die at random, reproducibility of directionality is extremely low if the preform is introduced into the molding die at random. Therefore, a method of supplying and supporting the preform on the preform support by rotating so that the mark attached to the preform is directed to a predetermined direction, and supplying the preform to the preform support at random, and then applying the preform to the preform, A method of rotating the preform support so that the marked mark points in a predetermined direction, and supplying and supporting the preform support to the preform support while rotating both the preform and the preform support in opposite directions, in a predetermined direction. We are trying to mold a directional bottle, for example, by turning it to the right direction.

[0010]

For various purposes, a bottle is formed by giving a bottle a certain function, in other words, giving a direction so as to realize the purpose, by a blow molding by a hot parison method. In the method, the injection-molded preform is transferred to the molding die while being sandwiched by the injection molding die,
The hollow molded article is formed by supplying air into the preform, so that it is possible to form the article relatively arbitrarily.

However, in the blow molding method based on the cold parison method, usually, a preform having a bottom formed by injection molding is cooled to room temperature, and then softened by heating in the next step, and then the preform is placed in a molding die. To form a hollow molded product by supplying air into the preform, it is extremely difficult to form a directional bottle as it is, and the preform is introduced into the molding die. In doing so, it is necessary to introduce the preform with a certain direction. Therefore, some methods have been tried, but they are relatively arbitrarily difficult and difficult.

On the other hand, the cold parison method is different from the hot parison method in that the preform is intensively produced, and the preform is delivered to a place where the contents are filled or a nearby place, and formed into a bottle there. Suitable for mass production. Therefore, there has been a demand that a directional bottle can be formed relatively arbitrarily by the cold parison method.

The present invention can be applied to blow molding of hollow molded products such as beverage bottles, industrial containers, and large and small miscellaneous goods using bottomed preforms. By rotating the preform support on which the reform is supported, and stopping the rotation of the preform in a state in which the preform has directionality, a directional hollow molded article can be molded arbitrarily. It was made.

[0014]

According to the present invention, there is provided a method for positioning a preform in blow molding, which comprises moving a bottomed preform having a locking portion formed in the vicinity of a plug portion along a track. Heating, afterwards, a preform positioning method in a blow molding method of positioning a preform in a predetermined direction and introducing it into a molding die, supplying air into the preform to form a hollow molded product, This is a method in which the preform is rotated at least at a position immediately before the molding die, and a contact member capable of moving forward and backward is brought into contact with the locking portion to stop the rotation while the locking portion is directed in a predetermined direction.

A preform positioning apparatus for blow molding according to the present invention comprises a preform heating heater and a preform holding device for holding a bottomed preform having a locking portion formed near a plug portion. It consists of a track with a body, an air blowing nozzle for supplying air into the preform, a molding die for introducing the preform into a molding die with the preform positioned in a predetermined direction, and molding it into a hollow molded product. A preform positioning device in a blow molding device, which is capable of abutting / separating from a preform rotation device along a track and at a front position to be introduced into a molding die, and a locking portion of the preform, and And a contact body for stopping rotation while the locking portion is oriented in a predetermined direction.

More specifically, a preform holding body provided with a mandrel on the upper side along which the preform is fitted and held and a rotating portion with which the rotating body slides downward along the track, and a lower portion on the rotating portion. A rotation device consisting of a rotating body that rotates the preform holder by sliding by moving the air cylinder forward and backward is arranged.On the other hand, a preform is formed by moving the upper air cylinder forward and backward by being positioned above the rotating body. A stop device is composed of a contact body that comes into contact with and separates from the locking portion. The stop device moves forward and backward to the preform holder side in conjunction with or without interlocking with the advance / retreat of the rotating body.
This is a configuration provided in a state of retreating.

[0017]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a preform positioning method and apparatus for blow molding according to the present invention.

In addition, other than bottles, industrial containers, food containers, and large-sized blow-molded products using bottomed preforms.
The present invention can also be applied to blow molding of hollow molded articles such as small miscellaneous goods.

The blow molding apparatus used for molding a bottle according to the present invention includes a heater 102 for heating a preform P and a preform holder 26 for holding the preform P, as shown in FIGS. In addition to the trajectory, the air blowing nozzle 50 for supplying air into the preform P, the molding die 3 for molding a hollow molded product, the rotation device 27 of the preform P and the locking portion p3 of the preform P And a stopping device 40 having a contact body 42 in contact with the preform P.
Are located.

As shown in FIG. 1, the preform P used in the present invention has a bottomed shape, and is provided with a screw thread p1 and a neck ring p2 on which the plug is fitted on the outer surface of the plug. . On the surface of the preform P, a locking portion p3 such as a small protrusion is protruded.

The locking portion may be a screw thread itself other than the small projections shown in the figure.
It may be a depression provided in a screw thread or the like. The size of the locking portion depends on the size of the contact body that comes in contact with or separates from the preform or the locking portion, but is about 0.5 to 8 mm. The point is that the rotation of the rotated preform is stopped in a state where the preform has directionality, and it does not have to affect the stopper.

The preform may have no neck ring or a small neck ring.

The preform is made by melting a plastic such as polyethylene, polypropylene, vinyl chloride, polyethylene terephthalate, or polyacrylonitrile in a cylinder of an injection molding machine (not shown), and setting the melt in an injection mold having a cavity having a predetermined shape. Inject and molded.

The blow molding apparatus used in the present invention is shown in FIG.
As shown in FIG. 4, a heater 1 for heating a preform P
A heating line 1 having a mold 02 and a stretching blow line 2 having a molding die 3 and the like are separately disposed, and a positioning device 4 is disposed at least immediately before the molding die 3.

It is to be noted that a molding step in which a heating step and a biaxial stretching blowing step (or blowing step) are arranged on the same track without dividing into a heating line and a stretching blowing line may be used.

The positioning device 4 of the present invention includes a preform holder 26 to which the preform P is fitted and held, a rotation device 27 for rotating the preform holder 26 and the preform P, The stop device 40 includes a contact member 42 that comes into contact with the stop portion p3 to stop the rotation of the preform P and the preform holder 26.

The preform holding member 26 is provided with a mandrel 261 on which the preform P is fitted and held, and a rotating member 41 such as a rotating belt described below slides on the preform holding member 26 to slide the preform holding member 26 downward. A rotating unit 262 such as a pulley that rotates is provided. , Preform holder 2
6 is a hole 2 formed in a base 28 wider than the gap 25.
A state 82 is fitted so as to be able to rotate via bearings.

A plurality of rollers 29 sandwiching a metal guide 23 are provided on the back surface of the base 28, and guide pins 221 projecting from the belt conveyor 22 are fitted to the end surface on the side of the belt conveyor 22. A hole 281 is formed.

The base 28 on which the preform holder 26 is fitted is along the track constituting the stretch blowing line 2, and more specifically, the belt conveyor 22 which is wound around the sprocket 21 on the base 20. And a metal guide 23 provided therearound. That is, a belt conveyor 22 is wound around a sprocket 21 rotatably provided on a base 20, a metal guide 23 is arranged around the belt conveyor 22, a gap 25 is formed, and a track of the extension blow line 2 is formed. And this gap 2
5, the belt conveyor 22 (or the metal guide 2)
It is rotatably mounted along 3).

Since the preform holder 26 is arranged along the track passing almost at the center of the molding die 3,
By controlling a driving source 24 such as a servomotor connected to the sprocket 21 of the belt conveyor 22, the front position introduced into the molding die 3 can be moved intermittently or continuously.

The preform holder 26 has an endless chain conveyor wrapped around a sprocket on a base, and is fitted into a hole formed in a connection shaft of the conveyor with a bearing interposed therebetween. Alternatively, a hole may be formed in the edge of the rotating disk while the bearing is interposed in the hole.

The rotating part of the preform holder may be formed by forming a knurl or a shallow groove around the preform holder other than the pulley.

What is essential is that the preform holder be rotated in cooperation with the rotation device to assist the preform holder in rotating.

The rotation device 27 includes a preform holder 26.
A lower air cylinder 44 is placed on a base 43, a first mount 45 is provided on a shaft 441 of the air cylinder 44, and four sprockets 46 are arranged on the mount 45. In addition, a rotating body 41 such as a rotating belt is rotatably wrapped around the sprocket 46, and a driving source (not shown) such as a motor is connected to the sprocket 46.

The rotating body of the rotating device may be a rotating body other than a rotating belt, such as a roller or flywheel, which is rotated by a direct or indirect force of a driving source such as a motor. Further, other than indirectly rotating the preform holder using a rotating body such as a rotating belt, a power source is connected to the preform holder directly or through a belt or a chain roller, and this is connected to a predetermined power source. It may use a torque limiter or a clutch that cuts off the edge with the power source after being rotated at a position and then becomes free.

In the case of the forming step in which the heating step and the blowing step are on the same track, the rotation from the time of heating may be continued.

The stopping device 40 is for stopping at least the preform P in a predetermined direction.
As shown in FIGS. 5 and 8, the preform P includes a contact body 42 which can be brought into contact with / separated from the locking portion p3 of the preform P, and which stops its rotation while the locking portion p3 is oriented in a predetermined direction. is there.

The contact member 42 of the stopping device 40 is capable of coming into contact with and separating from the locking portion p3 of the preform P, and
Is stopped in a state in which the preform P is oriented in a predetermined direction, and the second mounts 47, 471, and 47 are located at positions above the first mount 45 to which the spinning device 27 is attached.
472 is provided, and the upper air cylinder 48 is mounted on the second frame.
81 is mounted via a support 49.

The contact body 42 is usually a rod as a whole, and its tip has a shape such as a cone, a circle, or a flat shape so that the locking portion p3 can be easily locked. The length is about 0.8 to 10 mm, which is slightly larger than the locking portion p3. The point is that the preform that has been rotated can be stopped in a state where the preform has directionality.

Further, it is preferable that a soft small spring is incorporated in the rod so that the distal end portion comes into contact with the locking portion without difficulty.

The operation of the stopping device 40, in other words, the operation of the rotating body 41 such as the rotating belt of the rotating device 27 and the operation of the rod-shaped contact member 42 of the stopping device 40 are performed by integrating the rotating device 27 and the stopping device 40 shown in FIG. It will be described with In FIG. 4, the mandrel 2 of the preform holder 26 is
Reference numeral 61 denotes a diameter at which the fitted and held preform P does not enter a loosely fitted state, and the outer diameter of the mandrel 261 and the inner diameter of the preform P are substantially zero clearance.

At the beginning of the operation, the lower air cylinder 4
4 and the shaft 441 of the upper air cylinder 48,
Reference numeral 481 denotes a retracted (lowered) state, and the rotating body 41 such as a rotating belt is rotated by a driving source (not shown).

From this state, the lower air cylinder 44
By rotating the preform holding body 26 by rotating the preform holding body 26 by rotating the rotating body 41 such as a rotating belt attached to the shaft 441, the sliding body 262 is brought into sliding contact with the rotating portion 262 of the preform holding body 26. Preform P
To rotate. (In FIG. 4, the rotating body 41 is in contact with the rotating portion 262.) After rotating the preform P, the rotating body 41 such as a rotating belt is moved backward by operating the lower air cylinder 44.

Simultaneously or afterwards, the upper air cylinder 4
By the operation of 8, the rod-shaped contact body 42 attached to the shaft 481 is advanced, and the tip of the contact body 42 comes into contact with the locking body p3 formed on the rotating preform P, The rotation of the preform P and the preform holder 26 is stopped with the locking body p3 oriented in a predetermined direction. (In FIG. 4, the contact body 42 is in contact with the parison P.) After the preform P is stopped, the rod-shaped contact body 42 is operated by operating the upper air cylinder 48.
Retreat. (Return to the initial state.) Retreat is performed by a preset timer.

The forward / backward operation of the contact body of the stop device is
As explained with the rotating body of the rotation device and the contact body of the stop device,
This operation is, for example, a method using a timer for operating a contact body of a stopping device, a method using synchronization with a conveyor equipped with a rotation device, a method for optically detecting a preform on a preform holding member, and the like. May be performed.

The stopping direction of the locking member of the preform is intentionally determined based on the bottle shape, pattern / label, and plug type, for example, from an optimal combination of the bottle shape (or pattern / label) and the plug type. Usually, the stop position of the locking member is determined by, for example, separating the stop position of the locking body by a predetermined angle (or on the line) with the parting line of the mold as a reference line.

Although the stopping device has been described as a pair with the rotation device, the present invention is not limited to this. For example, a control mechanism set in advance can be used without using a rotation device separate from the preform holder. The rotation of the preform holder may be stopped by a contact device which moves forward and backward by the operation of a spring or an air cylinder.

Also, without integrating the rotation device and the stopping device, the rotation device and the stopping device are independently provided on the base as shown in FIG. 8, and these are operated by the control mechanism in a predetermined operation. You may do so. In FIG. 8, the mandrel 261 of the preform holder 26 has a diameter in which the preform P to be fitted and held is slightly loosely fitted, and the outer diameter of the mandrel 261 is: The preform P is extremely slightly smaller than the inner diameter of the preform P, and the preform P spins on the mandrel 261.

FIG. 8 shows the rotation device 27 and the stopping device 40 of the positioning device 4 separated from each other. From this state, the shaft 44 is operated by operating the lower air cylinder 44.
The rotating body 41 such as a rotating belt attached to 1 is moved forward to make sliding contact with the rotating portion 262 of the preform holding body 26, thereby rotating the preform holding body 26, and removing the preform P held thereon. Rotate. (In FIG. 8,
The rotator 41 is in contact with the rotator 262).
After rotating the preform P, at the same time or afterward, the operation of the upper air cylinder 48 causes the shaft 48 to rotate.
1. The rod-shaped contact member 42 attached to 1 is advanced, and the tip of the contact member 42 abuts on the locking member p3 formed on the rotating preform P, and the locking member p3 is moved in a predetermined direction. P and preform holder 2 in a state facing
The rotation of 6 is stopped. (In FIG. 8, the contact body 42 is in contact with the parison P). At this time, since the preform P is slightly loosely fitted to the preform holder 26, the preform P is stopped but the preform holder 26 is rotating.

After the preform P is stopped, the rotating member 41 such as a rotating belt is retracted by operating the lower air cylinder 44, and the rotating state of the preform holding member 26 is stopped.

Thereafter, the rod-shaped contact body 42 is moved backward by operating the upper air cylinder 48. (Return to the initial state.) Retreat is performed by a preset timer.

Based on FIGS. 2, 3, 6 and 7,
The heating line 1 and the stretch blow line 2 constituting the blow molding apparatus will be described.

The heating line 1 has a sprocket 11 rotatably provided on a base 10, and a chain conveyor 12 is hung on the sprocket 11 to form a track of the heating line 1.

A drive source 13 such as a servomotor is connected to one of the sprockets 11, and the preform P is moved by rotating the chain conveyor 12 on the base 10.

The chain conveyor 12 intermittently or continuously moves under the control of the drive source 13 to move the preform P on the chain conveyor 12 intermittently or continuously.

As shown in FIG. 3, a preform support 14 for supporting the preform P is attached to the chain conveyor 12.
Is attached so that it can rotate. In the preform support 14, the mandrel 15 into which the preform P is fitted and supported is engaged with a connecting member (not shown) such as a belt or a chain below to rotate the preform support 14. There is provided a sprocket 16 for causing this to occur.

A heater 102 is provided along the chain conveyor 12.

The heater is composed of a heating mold for heating by adjusting the temperature of the mold according to the strength of the alternating magnetic flux given to the mold for holding the preform and a heater group vertically provided facing the chain conveyor. Such as a heater. In FIG. 2, the preform P is conveyed while rotating on the preform support 14 of the chain conveyor 12, and is heated by the heater.

In the heating line 1, a preform supply line 101 for supplying a preform P injection-molded by an injection molding machine (not shown) outside the line 1 to the heating line 1.
Is connected.

In addition to the positioning device 4, a molding die 3 for molding the preform P into a hollow molded product and a product take-out device 8 for taking the hollow molded product out of the line are provided in the stretching blow line 2.
Is arranged.

The molding die 3 is for introducing a preform P heated and softened by the heater 102 and molding it into a hollow molded product. Usually, two molding dies 31 and 32 having cavities on the inner surface are used. , Face to face as a set. And
The mating surface between the molds 31 and 32 (parting line)
Can be used as a reference line for determining the direction of the preform P.

The molding die 3 is provided with a stretching device 5 having an air blowing nozzle 50 and a mold clamping device 6 for clamping and opening the molding die 3.

A stretching device 5 having an air blowing nozzle 50
As shown in FIG. 6, a pair of an upper plate 53 having a predetermined length to which a cylinder block 52 having a pair of head portions 51 and 51 is fixed, and an intermediate plate 54 and a lower plate 55 parallel thereto. The stretch rod 56, the ball screw 57 and the guide rod 59 are arranged at predetermined intervals.

The stretch rod 56 has an upper end portion penetrating the head portion 51 and the other end portion connected and fixed to the intermediate plate 54. The stretch rod 56 is provided with an air blowing nozzle 50, A gap for blowing air into the preform P is formed between the stretch rod 51 and the preform P.

The stretch rod 56 is operated by jointly and rotationally driving a rotary drive source 58 such as a servomotor or the like, a pulley, an endless belt or the like, and the ball screw 57 is rotated. The intermediate plate 54 is moved up (or down).

Although the air blow nozzle 50 having a stretching function by the stretch rod 56 has been described, blow molding by an air blow nozzle having no stretching function may be used.

As shown in FIG. 7, the mold clamping device 6 includes two links 61 and 62 with respect to a rotating disk 60 supported by the shaft.
Are rotatably mounted opposite to each other at 180 degrees, and one end of one link 61 is rotatably mounted on the back surface of one platen 63 located at the center, and the other link 62 is rotatably mounted. Platen support plate 6 whose other end is located on the right side
4 is rotatably mounted on the rear surface.

Two molds 3 each having a cavity on the inner surface
1 and 32 face each other as one set,
Is mounted on one platen 63 located at the center, and the other mold 32 is mounted on the other platen 65 located on the left side.

Reference numeral 601 shown in FIG. 7 is a bottom-type lifting device for forming the bottom of the bottle.

The preform transfer device 7 shown in FIG. 2 is a device for transferring the preform P heated by the heating line 1 to the stretching blow line 2.

The preform transfer device 7 includes the heating line 1
And the upper part of the stretching blow line 2 is cross-linked and arranged, and the plug part side of the preform P on the heating line 1 is gripped and raised vertically, and then moved horizontally in that state, It is lowered directly below and transported onto the stretch blowing line 2.

The take-out device 8 shown in FIG. 2 is a device for taking out a hollow molded product such as a bottle blow-molded by the molding die 3 in the stretch blow-in line 2 out of the line. After grasping the plug portion of a hollow molded product such as a bottle being formed with a gripping body, the gripping body is rotated by 180 degrees to transfer the hollow molded product such as a bottle to a conveyor at a predetermined position.

With the positioning device 4 of the present invention, the preform P is rotated by the rotation device 27 and
The operation of stopping the rotation in a state in which the locking portion p3 is directed in a predetermined direction is as follows.

The stopping operation of the preform P is performed by
Stop device 4 comprising a rotation device 27 comprising a contact body 42
2 and FIG. 4 and FIG.

First, the bottomed preform P having the locking portion p3 formed near the plug portion is heated by the heater 102 of the heating line 1.

Then, the heated preform P is inserted into the preform holder 26 of the stretch blowing line 2 by the preform transfer device 7. Later, preform holder 2
In a state where the preform 6 and the preform P can rotate, the preform P is moved along the track toward the inside of the molding die 3 for performing the hollow molding. Note that the fitting into the preform holder 26 is performed by inserting the mandrel 261 of the holder into the preform holder 26.
The plug section of the preform P is placed in an inverted state.

When the preform P is introduced into the molding die 3, the preform P is rotated at a front position where the preform P is introduced into the molding die 3. The rotation of the preform P is performed by rotating the preform P on the rotating portion 262 of the preform holder 26 into which the preform P is fitted.
The preform holder 26 is rotated by sliding the rotating body 41 of the rotating device 27 in a rotating state.

Then, immediately after the preform P is rotated, or a short while later, the contact body 42 of the stopping device 40 is advanced, and the contact body 42 is brought into contact with the locking portion p3 of the preform P in the rotated state. Then, the rotation of the preform P and the preform holder 26 is stopped in a state where the locking portion p3 is oriented in the predetermined direction.

In this state, usually, the locking portion p is determined with reference to the patent line formed by the dies 31 and 32.
3 is introduced into the molding die 3 while being aligned with the patenting line or separated by a predetermined angle.

Subsequently, air is supplied and blown into the preform P which is positioned in a predetermined direction and is introduced into the molding die 3 through an air blowing nozzle to form the preform P into a predetermined shape. Into a hollow molded article.

This hollow molded article is formed into a hollow molded article having an intended direction.

[0082]

As described above, the present invention can be positioned with the preform oriented in a predetermined direction when the preform is introduced into a molding die for blow molding a hollow molded product. Therefore, a hollow molded article such as a directional bottle can be arbitrarily molded.

In particular, in the blow molding method by the cold parison method, a bottomed preform is heated while being moved along a track, and is then introduced into a molding die with the preform positioned in a predetermined direction. Then, by supplying air into the preform through an air blowing nozzle, a directional hollow molded product can be arbitrarily molded, and a hollow having various shapes such as an oval, a rectangle, a square and a circle can be formed. In a molded article, the range of applications of the pattern / label and the type of plug attached thereto is widened, which helps to increase the commercial value.

[Brief description of the drawings]

FIG. 1 is a partially cutaway side view showing a typical example of a bottomed preform.

FIG. 2 is a plan view of the blow molding apparatus.

FIG. 3 is a cross-sectional side view of a main part showing conveyance of a preform heating line.

FIG. 4 is a front view showing a positioning device.

FIG. 5 is a plan view showing a main part of the positioning device.

FIG. 6 is a front view showing a stretching device.

FIG. 7 is a side view showing a mold clamping device with a stretching device and a bottom mold elevating device.

FIG. 8 is a front view showing another example of the positioning device.

[Explanation of symbols]

 P Preform p1 Screw thread p2 Neck ring p3 Locking part 1 Heating line 101 Preform supply line 102 Heater 10 Base 11 Sprocket 12 Chain conveyor 13 Drive source 14 Preform support 15 Mandrel 16 Sprocket 2 Stretching blow line 20 Table 21 Sprocket 22 Belt Conveyor 221 Guide Pin 23 Guide 24 Drive Source 25 Gap 26 Preform Holder 261 Mandrel 262 Rotating Part 27 Rotating Device 28 Base 281 Hole Part 282 Hole Part 29 Roller 3 Molding Dies 31, 32 Mold 4 Positioning Device 40 Stopping device 41 Rotating body 42 Contact body 43 Base plate 44 Lower air cylinder 441 Shaft 45 First mount 46 Sprocket 47 Second mount 471, 472 Second mount 48 481 Shaft 49 Support 5 Stretching device 50 Air blowing nozzle 51 Head 52 Cylinder block 53 Upper plate 54 Intermediate plate 55 Lower plate 56 Stretch rod 57 Ball screw 58 Drive source 59 Guide rod 6 Mold clamping device 601 Bottom type lifting device 60 Rotating disk 61, 62 Link 63 One platen 64 Platen support plate 65 The other platen 7 Preform transfer device 8 Product take-out device

Claims (3)

[Claims] 1. A mold having a bottomed preform having a locking portion formed in the vicinity of a plug portion is heated while moving along a track, and then the preform is positioned in a predetermined direction to form a molding die. Is a method of positioning a preform in a blow molding method in which air is supplied into the preform to form a hollow molded product, and the preform is rotated at least immediately before a molding die and locked. A method for positioning a preform in blow molding, wherein the rotation of the preform is stopped in a state where a contact member capable of moving forward and backward is brought into contact with the part and the locking part is oriented in a predetermined direction. 2. A track having a heater for heating a preform, a track provided with a preform holder for holding a bottomed preform having a locking portion formed in the vicinity of a plug portion, and a track inside the preform. A preform positioning device in a blow molding device comprising an air blowing nozzle for supplying air and a molding die for introducing the preform into a molding die in a state where the preform is positioned in a predetermined direction to form a hollow molded product. hand,
A preform rotation device that is located along the track and at the front position to be introduced into the molding die, and is capable of coming into contact with and separating from the locking portion of the preform, and rotating with the locking portion oriented in a predetermined direction. And a stopping device having a contact body to be stopped. 3. A preform holder having a mandrel on the upper side along which the preform is fitted and held, and a lower portion provided with a rotating portion on which a rotating body slides, and a lower air cylinder mounted on the rotating portion. A rotation device consisting of a rotating body that slides by moving forward and backward to rotate the preform holding body is arranged. On the other hand, a preform engaging portion is located above the rotating body and is moved forward and backward by an upper air cylinder. A stop device is constituted by a contact body that comes in contact with or separates from the preform holder, and the stop device is provided in a state of moving forward / backward to the preform holding member side in conjunction with or without interlocking with the advance / retreat of the rotating body. 3. The apparatus for positioning a preform in blow molding according to claim 2, wherein: