JP2008302635A - Injection blow molding machine and neck mold transfer device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mechanism which is almost free from mechanical distortion/deflection and vibration as causes for the manufacture of a non-conforming product, in an injection blow-molding machine capable of blow-molding in one machine. <P>SOLUTION: An injection mold closing device which requires a strong mold clamping force and a blow molding device, are arranged together with a transfer device for an injection mold and a neck mold which becomes a part of a blow mold in the way that these devices are independently discrete from each other without mutual contact. Further, in order to reduce the deflection generated by the weight of a rotating disc itself for rotatably transferring the neck mold and the inertia of the rotation, the doughnut-type rotating disc is adopted, thus making the disc lightweight. In addition, only the rotating disc and a retainer plate for retaining the former are used for the ascent/descent of the neck mold, thus making the neck mold assembly lightweight and simple-structured. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an injection blow molding machine capable of performing injection molding of a preform with a thermoplastic resin and blow molding or stretch blow molding of a thin bottle or the like in the same machine, and a neck type moving device in the machine. .

  The injection blow molding machine has processes such as preform injection molding, temperature control, blow, product removal, etc., and the equipment is installed in the same machine, and the injection molded preforms are intermittent in this order. Moved into a product.

In the injection molding process section of the injection blow molding machine, the preform mold is inserted into the in-cab on the hot runner installed on the lower base, and the neck mold installed on the rotating plate is inserted into the mold clamping plate. The attached incore is structured to be inserted into the neck shape. In order to eliminate the centering and tilting of the in-cab and in-core, the in-cab and neck type, the neck type and the in-core are fitted with a taper.

In a conventional injection blow molding machine, the fixed plate that holds the rotating plate on the upper part of the lower base is inserted into the tie bar of an injection mold closing device, and a clamping cylinder is connected to the fixed plate. Yes.

In a blow process section of a conventional injection blow molding machine, a blow device for inserting a core into a preform neck and blowing high-pressure air is installed on a fixed plate.

In the neck type moving device of the conventional injection blow molding machine, the disc-shaped rotating plate that is installed at the lower part of the fixed plate and attaches the neck type is lifted on the shaft at the center, and rotates around the shaft, The raising / lowering movement for inserting the neck mold into the injection mold involves raising / lowering together with the fixed plate and the rotating plate, dividing the rotating plate up / down independently, or raising / lowering the injection die.
No. 1-018848 Patent No. 1899249 JP 2005-7797 A

In the above prior art, the fixed plate that holds the rotating plate for moving the neck mold is inserted through the tie bar of the injection mold closing device, and the mold clamping cylinder is installed on the fixed plate. A blower for blowing high-pressure air is also installed on the fixed plate.

In such a conventional technique, the fixing plate is distorted by the clamping force, which affects the fitting between the neck mold and the in-core and the neck mold and the in-cab, and causes the in-core and the in-cab to be tilted. The force that lifts the fixed plate due to the reaction force of the pressure acts to displace the entire injection mold, causing unevenness in the preform, which is an injection molded product, and unevenness in the product, such as a bottle. It has the problem that it ends up.

  In the above prior art, in the rotational movement of the neck type, the entire rotating plate to which the neck type is attached is rotated around the center of the rotating plate. Rotation of the entire rotating plate has high inertia and high speed cannot be achieved, and since the rotating plate is suspended from the rotating shaft, the rotating plate itself becomes bent like an umbrella due to its own weight, causing unstable rotation. In this case, the bending of the preform causes the uneven thickness of the preform as described above.

In the above-described prior art, there is a problem that in the neck type raising / lowering, mass is large when the fixed plate and the rotating plate are raised / lowered together, it is difficult to increase the speed, and the single raising / lowering that divides the rotating plate makes the device complicated.

In order to solve the above-mentioned problems, the invention of claim 1 is a fixing in which an injection molding mold closing device, a blow molding blow device and a neck type moving device are installed on a lower base having a blow mold clamping cylinder installed on the upper surface. The board is installed directly and independently.

In the configuration of the present invention, the injection force and the reaction force of the blow air are directly transmitted to the tie bar at the time of injection molding and blow molding, so that the fixing plate is not distorted or warped. For this reason, there are advantages such that the stacking accuracy of the injection mold is improved, the uneven thickness is reduced, and the mold life is increased.

  In the invention of claim 2, the rotating plate installed under the fixed plate is reduced to a donut shape by keeping the width necessary for rotating the neck mold, and the weight is reduced and the load capacity attached to the holding plate is large. Only the rotating plate is rotated through a large slewing bearing.

The rotating plate in the above is supported by a large slewing bearing on the inner side of the donut shape, and since its supporting diameter is large, there is no bending due to its own weight, the injection mold is not affected by the bending, and the rotational force and inertia are reduced. Therefore, there is an advantage such as high speed and energy saving effect.

  The neck type lifting device according to the second aspect of the present invention lifts and lowers only the rotating plate and the bearing holding plate that holds the rotating plate, and has advantages such as weight reduction, energy saving effect, and simplified structure.

  The present invention has the effect of improving the quality of the product, reducing the defect rate, increasing the service life of the mechanical mold, saving energy, and simplifying the structure.

FIG. 1 is a plan view. On the lower base 1, an injection mold closing device 33, a fixing plate 2 and a blow device 34 are independently installed.

  FIG. 2 is a cross-sectional view of the mechanism. Left and right blow cylinders 22a and 22b are installed on the lower base 1, and a fixing plate 2 is connected and fixed in parallel with the lower base 1 by a plurality of support bases 3a and 4b and a shaft 5 passing through the center. .

A bearing holding plate 10 is inserted into the shaft 5 below the fixed plate 2 and is connected to the fixed plate 2 by an elevating cylinder 13 and an elevating piston 14 so as to freely move up and down. A donut-shaped rotating plate 11 is connected to the bearing holding plate 10 through a swivel bearing 12 with a gear, and the rotating plate is rotated by a drive motor 16 and a small gear 17 installed on the bearing holding plate.

FIG. 3 is a half vertical sectional view of the injection mold closing device. The mold clamping cylinder 6 is supported by a diver 9 erected from the lower base 1, and the mold clamping plate 8 is inserted into the tie bar 9 and connected to the mold clamping piston 7 so as to be movable up and down.
The injection mold closing device is directly and independently installed on the lower base.

FIG. 4 is a half sectional view of the blowing device. The blow core cylinder base 23 is supported by a blow tie bar 29 erected from the lower base 1, and the stretching cylinder base 24, the blow core mounting plate 25, and the stretching rod mounting plate 26 are installed through the blow tie bar 26. This blower is installed directly and independently on the lower base.

  The mechanical device of the present invention is an improved type of the conventional machine and can be industrially mass-produced, and thus has industrial utility value.

It is a top view concerning this invention. It is a longitudinal side view similarly. It is a half section front view of the injection mold closing device. It is a half section front view of the blow device.

Explanation of symbols

1 Lower base 2 Fixing plate 3a Support base A
4b Support base B
5 Shaft 6 Mold clamping cylinder 7 Mold clamping piston 8 Mold clamping plate 9 Tie bar 10 Bearing holding plate 11 Rotating plate 12 Swivel bearing 13 Lifting cylinder 14 Lifting piston 15 Guide rod 16 Drive motor 17 Small gear 18 Incore 19 Neck mold 20 Incavity 21 Hot Runner 22a Blow mold clamping cylinder A
22b Blow mold clamping cylinder B
23 Blow core cylinder base 24 Stretch cylinder base 25 Blow core mounting plate 26 Stretch rod mounting plate 27 Blow core 28 Stretch rod 29 Blow tie bar 30 Stopper nut 31 Blow mold 32 Heating cylinder 33 Injection mold closing device 34 Blow device

Claims (2)

In an injection blow molding machine that forms a packaging container such as a thin bottle by transferring an injection molded bottomed plastic preform into a blow mold and stretching and expanding it in the axial direction and the radial direction by a stretching rod and blow air.
Injection mold closing device, air blowing blow device and neck mold rotation, fixed plate that holds the lifting device (neck type moving device) are independently installed on the lower base, injection blow Molding machine. In the neck type moving device of the injection blow molding machine, the rotating plate to which the neck die is attached has a donut shape having a width necessary for opening and closing the neck die, and is connected to the holding plate through a turning bearing having a gear. A neck type moving device characterized in that it can be rotated by a drive motor and a gear installed on a holding plate, and the holding plate can be raised and lowered by a cylinder and a piston installed on a fixed plate.

Images