JP4708926B2 - Hollow molding equipment - Google Patents

Description

  The present invention relates to a hollow molding apparatus that can reliably recover an upper flash that is a resin surplus portion of a mouth portion that is generated when a hollow molded product made of a synthetic resin is blow molded.

  The hollow molding device is an extruder that heats and melts a thermoplastic resin and continuously extrudes it from a die using a screw. A compressed air is blown through a blowing nozzle into an extruded parison and expanded in a closed molding die. It has a blower and a transport mechanism for blown hollow molded products.

  The occurrence of top flash in hollow molding is because the upper part of the parison introduced into the molding die is protruded slightly upward from the pair of split molds forming the molding die and is cut by a cutter. This is because when the blow nozzle is lowered and driven into the parison in the molding die, it remains as a top beam. When the blow nozzle is driven into the parison, the upper beam has an upward tapered inner peripheral edge in the base provided at the pair of improved edges of the pair of split molds, and an outer peripheral edge of the cutting sleeve positioned above the injection nozzle. And is sheared and cut.

  Conventionally, the recovered top beam is collected in a state where the hollow beam attached to the blowing nozzle together with the top beam is gripped by a gripping machine, and the top beam is attached to the blowing nozzle according to the upward movement of the blowing nozzle. Remove from the hollow molded product. The released upper beam is brought into contact with a drop plate located above the nozzle by further upward movement of the blowing nozzle, removed from the blowing nozzle, dropped into the space, and blown out from the nozzle in the vicinity of the dropping position simultaneously with the dropping. The air is collected by being blown into a shooter opened in a wide mouth shape by air.

  Such a method of collecting the top beam is an effective method in a narrow work area, but usually there is an open space portion whose height to the drop plate is 4 cm to 8 cm. In some cases, it is not blown away well from the part into the shooter, or it is scattered around the hollow molding apparatus, and the top flash cannot be reliably recovered.

  Therefore, for example, as in the technique described in Patent Document 1, a method has been developed for recovering a dropped top beam with an air duct. Hereinafter, the top flash recovery method will be described with reference to FIGS. 10 to 12, 101 is a molding die, 102 is a blow nozzle, 103 is a base, 104 is a cutting sleeve provided on the top of the blow nozzle 102, and 105 is a nozzle body integrally formed with the blow nozzle. . In FIGS. 10 and 12, reference numeral 106 denotes a housing, 107 denotes a bottom hole for inserting a nozzle, 108 denotes a duct formed integrally with the housing 106, and 109 denotes a shaft that suspends the housing 106. These shafts 109 are fixed to a blower main body (not shown). Reference numeral 110 denotes a shutter that opens and closes the bottom hole 107.

  In such a hollow molding apparatus, as shown in FIG. 10, a pair of molding dies in a state in which a thermoplastic resin is heated and melted and continuously extruded from a die using a screw, and a parison P indicated by a one-dot chain line in the figure is opened. 101. Next, the molding die 101 is closed to hold the parison P, and the upper portion of the parison P is cut by a cutter (not shown) and is contained in the molding die. Thereafter, the blowing nozzle 102 is lowered, the upper beam is sandwiched between the tapered inner peripheral edge of the base 103 and the outer peripheral edge of the cutting sleeve 104 and sheared and cut, and compressed air is blown into the parison P through the blowing nozzle 102. Then, it is expanded in the molding die 101 and blow-molded into the hollow molded product 111.

Next, as shown in FIG. 11, the blow nozzle 102 with the cut top beam 112 is raised and passed through the bottom hole 107 of the housing 106, and the nozzle is inserted through the top beam 112 provided on the ceiling of the housing 106. The upper beam 112 is removed from the blowing nozzle 102 and the bottom hole 107 is dropped into the closed housing 106 by the shutter 110. As shown in FIG. 12, the fallen top beam 112 is transferred from the duct 108 to the housing 106 by air blown from an air outlet (not shown) provided in the housing 106 or a suction mechanism (not shown) connected to the duct 108. Drain out and collect.
JP 2003-53827 A

  However, the above-described top beam recovery method has a problem that a predetermined occupation space such as the housing 106 and the duct 108 is required in the molding apparatus itself in the mold clamping / blowing process. In addition, large parts for collecting the top beam are required, which increases the cost and complicates the control of these parts. Further, there is a fear that the shutter 110 may sandwich the flash.

  The present invention is intended to solve the problems of such a conventional hollow molding apparatus, and can be applied to a hollow molding apparatus having a narrow work area in a mold clamping / blowing process, and has a simple configuration. The purpose is to reliably collect the top beam by the top beam recovery mechanism.

In order to achieve the above-mentioned object, the present invention provides a gripping body provided with a receiving part for gripping a hollow molded product and receiving a top beam of the hollow molded product, and being close to the gripping body above the gripping body. Provided with a stopper body that abuts the upper flash attached to the blow nozzle when the blow nozzle rises after blow molding and drops it to the receiving portion, and the receiving portion of the gripping body expands upward. This is a hollow molding device having a different shape . The distance between the gripping body and the stopper body is preferably 5 mm to 20 mm in order to prevent scattering of the dropped top beam and to facilitate the reception of the dropped top beam at the receiving portion. The receiving portion has a size sufficient to receive and accommodate the upper beam.

  Further, the second problem solving means has a configuration in which the stopper body is provided with a throttle portion that causes the upper beam to come into contact with the stopper body while dropping through the blowing nozzle. The restricting portion has a function of causing the upper beam to contact and drop while passing through the blowing nozzle. For example, the restricting portion may be a notch portion, a hole portion, or a camera whose diameter can be changed, such as a camera shutter.

  The third problem solving means has a configuration in which the grip body and the stopper body are provided integrally.

According to a fourth problem solving means, the gripping body comprises a pair of split gripping bodies, and semi-annular notches for receiving and gripping the mouth of the hollow molded product on mutually facing surfaces of the pair of split gripping bodies. It is set as the structure which provided the part.

The fifth problem-solving means has a configuration in which a flange projecting toward the center of the notch is provided at the top and bottom of each of the pair of semi-annular notches.

The operation of the first problem solving means is as follows. That is, after blow molding, the upper flash attached to the blow nozzle is brought into contact with the stopper body and dropped as the blow nozzle rises, and is received and received by the receiving portion of the gripping body. At this time, the dropped upper beam is reliably captured by the receiving portion having a shape expanding upward. Next, the accommodated upper beam is carried by the gripping body and processed by, for example, mechanically forcibly collecting it in the next product take-out process. Therefore, this means can be applied even to a hollow molding apparatus having a narrow work area in the mold clamping / blowing process, and has an effect of ensuring the collection of the top beam by the mechanism for collecting the top beam having a simple configuration. .

  The operation of the second problem solving means has an effect that the upper beam is quickly and reliably separated from the blowing nozzle and dropped by the throttle portion of the stopper body.

  The operation of the third problem solving means eliminates the work area in which a separate stopper body is provided in a hollow molding apparatus having a narrow work area in the mold clamping / blowing process by integrating the grip body and the stopper body. As a result, the hollow molding apparatus having a narrower working area in the mold clamping / blowing process can be applied.

The effect | action by a 4th problem-solving means has an effect that the opening | mouth part of a hollow molded product is accommodated in a pair of semi-annular notch part, and it can hold | grip reliably.

The action of the fifth problem solving means is that the mouth of the hollow molded product is sandwiched between the top and bottom flanges of each of the pair of semi-annular notches, so that the mouth of the hollow molded product is There is an effect that it can be pinched and securely gripped.

  As described above, the hollow molding apparatus of the present invention has a narrow work area in the mold clamping / blowing process because the top beam of the hollow molded product can be dropped by the stopper body and received by the receiving part of the gripping body. It can also be applied to a hollow molding apparatus, and the recovery of the top cover can be reliably performed by the mechanism for recovering the top cover having a simple configuration.

  As shown in FIGS. 1 to 3, a hollow molding apparatus according to an embodiment of the present invention includes an extruder (not shown) that melts and extrudes a resin composition as an operation unit for molding, and a crosshead 1. , A parison cutting device (not shown), a molding die 2, a blowing device 3, a clamping device 4, a molding die moving device 5, and a molded product taking-out device including a flash cutting mechanism.

  The extruder (not shown) includes a hopper 7 for charging a resin composition and a screw (not shown) for transferring, kneading, melting, and discharging the resin composition inside the extruder.

  As shown in FIG. 1, the crosshead 1 is for multiple heads and is connected to the tip of an extruder. The resin composition melted in the extruder is supplied from the extruder to the crosshead 1 so that a cylindrical parison P indicated by a two-dot chain line in FIG. 2 is formed.

  The parison cutting device (not shown) cuts the upper part of the cylindrical parison P hanging from the crosshead 1 and includes a cutter holder having an electric heating cutter.

  As shown in FIGS. 2 and 3, the molding die 2 includes a pair of split molds 2 a and 2 b, and a cylindrical parison P is inserted into these split molds to form a hollow molded product B. The left and right cavities 2c and 2d are formed. The bases 2e and 2f for biting the top burr of the parison P are provided on the pair of improved edges of the cavities 2c and 2d of the split molds 2a and 2b. The inner peripheral edges of these caps 2e and 2f are formed with an upward taper to bite the upper beam.

  The molding die 2 is moved between a position immediately below the multi-head crossheads 1 and 1 and a position directly below the left and right blowing nozzles 8 and 8 by a molding die moving device 5 having an accompanying die moving motor. It can move back and forth alternately in the horizontal direction.

  As shown in FIGS. 1 and 2, the blowing device 3 includes a pair of blowing nozzles that are inserted into the cylindrical parison P and blown in compressed air above the left and right cavities 2 c and 2 d of the molding die 2. 8, 8 and a blowing nozzle drive device 9 for raising and lowering these blowing nozzles are provided. The blowing nozzle driving device 9 includes a variable speed type blowing device driving motor connected to a control unit (not shown).

  Compressed air is supplied to the blowing nozzle 8 so that air is blown into the parison P supplied into the left and right cavities of the molding die 2. As shown in FIG. 7, the upper part of the blow nozzle 8 is used for cutting shearing with the upper beam of the parison P in cooperation with the tapered inner peripheral edges of the caps 2e and 2f of the split molds 2a and 2b. A cutting sleeve 8a is formed. In FIG. 2, 8b shows a nozzle body.

  As shown in FIGS. 1 and 2, the mold clamping device 4 clamps the split molds 2 a and 2 b of the molding die 2, and a pair of horizontal molds arranged at a predetermined interval in a direction parallel to the paper surface. Rails 12 extending in the direction, a front platen 10 and a rear platen 11 provided on the rails 12 so as to be movable at predetermined intervals, and inserted through the platens 10, 11, and these platens are inserted into the parting line of the molding die 2. The left and right reverse lead ball screws 13 are moved in synchronism with the approaching / separating direction, the convex engagement portions 14 provided on the left and right sides of the platens 10 and 11, and the concave engagement portions for grasping the corresponding convex engagement portions. Located on the back side of the rear platen 11, the stop portion 15, the ball screw 16 coupled to the concave locking portion 15 so that the concave locking portion 15 can be pulled when the convex locking portion 14 is gripped. Left and right reverse leads A platen moving motor 17 connected to Lumpur screw 13, and a motor (not shown) is a servo motor for driving the ball screw 16 located on the rear side of the rear platen 11. The front platen 10 is detachably attached with the split mold 2a, and the rear platen 11 is detachably attached with the split mold 2b.

  Each of the left and right ball screws 16 is provided with pulleys 18 and 18 via a thrust bearing (not shown), and these pulleys 18 and 18 are connected to an electric motor (not shown) via an endless belt 19 and a speed reducer 6. ing. Note that FIG. 3 does not show the left and right reverse lead ball screws 13 and the rear side mechanisms of the rear platen 11 for the sake of explanation.

  The mechanism from the mold clamping device 4 to the flash cutting mechanism will be described. As shown in FIG. 3, the product holder 20 extends from the side surface of the platens 10 and 11, and after the blow molding is finished, the split molds 2a and 2b separated from each other. The hollow molded product B that has been released from the mold and suspended by the blowing nozzles 8 and 8 is sandwiched. After the mold 2 has moved directly below the blowing nozzle 8, the product restraining pin 40 is inserted into the hollow molded product B sandwiched between the product holders 20, and the tip of the pin is inflated with air to form a hollow molded product. B is held together with the top beam Bb shown in FIG. The take-out slide unit (not shown) is used in the next process while holding the hollow molded product B and the top beam Bb with the product restraining pins 40 after the split gripping bodies 21 and 22 of the product holder 20 are separated together with the mold opening. It moves to the lower beam cutting process.

  The lower beam cutting jig 42 in the lower beam cutting step is configured to cut the lower beam Bc shown in FIG. 7 in a state where the hollow molded product B is sandwiched between the second product holders 41. When the hollow molded product B is clamped by the second product holder 41, the product restraining pin 40 is lifted by releasing the holding of the hollow molded product B. When the product restraining pin 40 is raised, the upper flash Bb placed on the mouth portion Ba of the hollow molded product B is held by inflating the tip of the product restraining pin 40 with air, and the upper flash hold is released at the flash discharge portion. Thus, it is separated from the hollow molded product B and is forcibly excluded. However, it may be removed from the upper part of the product by air or the like on the spot.

  As shown in FIGS. 4 and 5, the product holder 20 includes a pair of left and right split grip bodies 21, 22 that sandwich and hold two hollow molded products B, and the split grip bodies 21, 22. It is comprised from the support bodies 23 and 24 which hold | maintain. The support members 23 and 24 are flat steel plates 23a and 24a, each of which has flat steel plates 23a and 24a and L-shaped steels 23b and 24b screwed together, and the split gripping bodies 21 and 22 fixed with screws. It is fixed with screws.

  As shown in FIG. 6, the split gripping bodies 21 and 22 are provided with semi-annular notches 21a and 22a for receiving and sandwiching the mouth of the hollow molded product B so that the mouth of the hollow molded product B can be gripped. At the top and bottom of these notches, annular upper collar portions 21b and 22b and annular lower collar portions 21c and 22c projecting toward the center of the notch are formed. Further, tapered portions 21d and 22d whose diameter is increased upward are formed on the upper flange portions 21b and 22b so that the cut upper beams can be placed thereon.

  The pair of stopper bodies 25 and 26 for abutment and dropping of the upper beam extend over the tapered portions 21d and 22d of the split gripping bodies 21 and 22 and are bolted to an upright plate 27 provided on the steel plate 23a. It is fixed by. The tip portions of the plate-like stopper bodies 25 and 26 form semi-circular cutout portions 25a and 26a. As shown in FIG. 9, the blower is blown into the stopper bodies themselves around the throttle portions 25a and 26a. The upper beam Bb that has moved up with the nozzle 8 is brought into contact with the nozzle 8 and the upper beam is dropped onto the receiving portions 21d and 22d of the split gripping bodies 21 and 22. The distance from the upper surface of the split gripping bodies 21 and 22 to the lower surface of the stopper bodies 25 and 26 is preferably 5 mm to 20 mm.

  Next, operation | movement of this hollow molding apparatus is demonstrated. As shown in FIG. 1 and FIG. 2, the blow molding by such a hollow molding apparatus first forms a left and right parison P in the horizontal direction in FIG. Are inserted into the left and right cavities 2c and 2d of the molding die 2, and then the blowing nozzles 8 and 8 corresponding to these parisons P are driven, and compressed air is blown into the parisons P to mold these parisons P. This is performed by expanding the mold 2 until it coincides with the cavities 2c and 2d.

  By this blow molding, a bottle which is a hollow molded product B is molded as shown in FIG. The upper part of the parison P is cut by a parison cutting device (not shown) when the molding die 2 is closed, and then the molding die 2 moves to the blowing device 3 side and the blowing nozzles 8 and 8 are lowered. Then, as shown in FIG. 7, shearing is performed by the die 2e, 2f of the molding die and the cutting sleeve 8a of the blowing nozzle introduced into the parison B. In FIG. 7, Bb indicates a trumpet-shaped upper beam whose diameter is increased upward, and Bc indicates a thin plate-shaped lower beam.

  When the mold 2 is opened, the hollow molded product B is suspended by the blow nozzle 8 together with the upper beam Bb attached to the tip thereof. As shown in FIG. 8, the hollow molded product B has the mouth portion Ba sandwiched between the pair of split gripping bodies 21 and 22 of the product holder 20 when the molding die 2 moves directly below the crosshead 1 and closes. Is gripped.

  After the gripping, as shown in FIG. 9, the blowing nozzle 8 is lifted, and the raised beam Bb that is lifted together is brought into contact with the stopper bodies 25 and 26 and dropped, and the receiving portions 21 d of the pair of split gripping bodies 21, 22 are 22d.

  Further, after the mold 2 is moved directly below the blowing nozzles 8 and 8, the product restraining pin 40 inserts the tip of the pin into the hollow molded product B and inflates the tip of the pin with air to lift the hollow molded product B up Bb Hold with.

  Thereafter, the split gripping bodies 21 and 22 of the product holder 20 are separated from each other with the mold opening, and the hollow molding product B and the top beam Bb are supported by the product restraining pins 40 by the take-out slide unit (not shown), Move to lower beam cutting process. In the lower beam cutting step, the lower beam Bc is cut by the lower beam cutting jig 42 in a state where the hollow molded product B is sandwiched by the second product holder 41.

  When the hollow molded product B is clamped by the second product holder 41, the product restraining pin 40 is lifted by releasing the holding of the hollow molded product B. When the product restraining pin 40 is raised, the upper flash Bb placed on the mouth portion Ba of the hollow molded product B is held by inflating the tip of the product restraining pin 40 with air, and the flash discharge portion holds the upper flash. After being released, it is separated from the hollow molded product B and forcibly removed.

  The hollow molded product B from which the upper beam Ba and the lower beam Bc have been removed is conveyed to the molding apparatus outlet by a belt conveyor (not shown).

  As described above, according to the present embodiment, the effect of surely removing the top beam can be obtained.

It is a front view of the hollow molding apparatus which shows embodiment of this invention. It is the side view to which the hollow molding apparatus shown in FIG. 1 was expanded. It is a perspective view which shows from the blowing apparatus shown in FIG. 2 to a flash cutting mechanism. It is a perspective view which shows a product holder. It is the perspective view which looked at the product holder shown in FIG. 4 from another direction. It is sectional drawing which shows the holding body of the product holder shown in FIG. It is sectional drawing which shows the split mold after shape | molding with the hollow shaping | molding apparatus shown in FIG. It is sectional drawing which shows the state which hold | gripped the hollow molded product with the holding body of the product holder. It is sectional drawing which shows the state which makes the top beam of a hollow molded product contact | abut to a stopper body, and is dropped. It is sectional drawing which shows the process which introduce | transduces a parison in a shaping die with the conventional hollow molding apparatus, and makes it a hollow molded product. It is sectional drawing which shows the state which suspended the hollow molded article shown in FIG. 10 at the blowing nozzle. It is sectional drawing which shows the state which introduce | transduces and falls the top beam of the hollow molded product shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Cross head 2 ... Molding die 3 ... Blowing device 4 ... Clamping device 8 ... Blowing nozzle 20 ... Product holder 21,22 ... Split gripper body 21b, 22b ... Upper collar part 21c, 22c ... Lower collar part 21d, 22d ... Receiving part 25, 26 ... Stopper body 25a, 26a ... Drawing part 40 ... Product constraining pin B ... Hollow molded product Ba ... Hollow molded part Bb ... Upper beam Bc ... Lower beam

Claims (5)

A gripping body provided with a receiving portion for gripping the hollow molded product and receiving the top beam of the hollow molded product;
A stopper body provided close to the grip body above the grip body, and when the blow nozzle rises after blow molding, a stopper body that abuts the upper flash attached to the blow nozzle and drops it to the receiving portion;
Equipped with,
The hollow molding apparatus characterized in that the receiving portion of the gripping body has a shape that expands upward .   2. The hollow molding apparatus according to claim 1, wherein the stopper body is provided with a throttle portion that causes the upper beam to come into contact with the stopper nozzle and to drop the stopper body into the receiving portion.   The hollow molding apparatus according to claim 1 or 2, wherein the grip body and the stopper body are integrally provided. The gripping body comprises a pair of split gripping bodies, and a semi-annular notch for receiving and gripping the mouth of the hollow molded article is provided on the mutually facing surfaces of the pair of split gripping bodies. The hollow molding apparatus according to any one of claims 1 to 3. The hollow molding apparatus according to claim 4, wherein a flange portion projecting toward the center of the notch portion is provided at a top portion and a bottom portion of each of the pair of semi-annular notch portions .

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