JP3410363B2 - Blow mold for biaxially stretched bottle with handle - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biaxially stretched preform formed by biaxially stretching a preform and having a handle on the side of a thin-walled bottle body. It relates to a blow mold for a bottle. [0002] A biaxially stretched bottle known as a PET bottle is formed by inflating an injection-molded preform by air blow while extending it in an axial direction to form a thin wall. Unlike direct blow-molded bottles that use only air blow, it is difficult to mold a part of the bottle body into a handle.Currently, a separate handle is attached by insert molding or a handle is attached after the bottle body is molded. Is either. As a biaxially stretched bottle to which a handle is attached after the bottle is formed, as shown in FIG. 5, after the bottle body 1 is formed, a separate handle 2 is formed on the upper surface at the same time as the bottle body 1 is formed. The upper and lower arms 5 and the legs 6 inside the grip 4 are inserted into the recess 3, and the locking projections 5 a, 6 a projecting from the upper and lower surfaces thereof are formed on the upper and lower wall surfaces 7, 8 of the recess 3. There is known a structure in which the handle 2 is locked by fitting the fixing plate 9 after fitting into the recesses 7a, 8a. The present invention ensures the formation of the recesses 7a and 8a in a biaxially stretched bottle in which the handle 2 is later attached to the bottle body 1 as in the above structure, and separates the bottle body 1 from the mold. The recess 7a, so as not to interfere with the mold,
It is intended to provide a blow mold having a projection for molding 8a. [0005] A blow mold in which a block-shaped concave forming die for attaching a handle is protruded in a cavity for forming a bottle body and projections for forming a concave are provided on upper and lower surfaces thereof so as to be able to protrude and retract is disclosed in US Pat. No. 6,637,167, it is of such a degree that a molding protrusion is made to protrude and retract from the upper and lower surfaces by an air cylinder, and lacks a specific configuration. The molding of the recesses 7a and 8a must be performed before the resin for molding the upper and lower wall surfaces 7 and 8 of the recess 3 is completely solidified. It is necessary to maintain the protruding state until no deformation occurs even after removing. Further, as a blow mold, a structure in which the projecting / retracting means of the molding protrusion is easily incorporated into the concave molding die, and a structure in which the molding projection can be reliably moved in and out with a small operation stroke is being considered. The present invention was conceived in view of the above circumstances, and the problem of this type of blow mold for a biaxially stretched bottle with a handle must be solved by employing an L-shaped forming lever and a pressing member. Is what you do. SUMMARY OF THE INVENTION The present invention according to the present invention has the above object, and comprises an openable mold for forming a cavity of a bottle body by a pair of split dies, and a portion for forming an upper side surface of the bottle body in the cavity. And a block-shaped concave forming die for attaching a handle, which is fitted and protruded from the side surface of the die,
It has a concave-shaped protrusion at the tip in the shape, and the rear end is rotatably mounted on the shaft so that the formed protrusion projects on the upper and lower surfaces of the concave-shaped mold. A pair of upper and lower forming levers provided, a pressing member movably provided on the back surface of the forming lever, and connected to both forming levers by a link plate, and an operating member on a side surface of the mold laterally provided on the pressing member. It consists of DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference numeral 11 denotes a blow mold, which forms a cavity 12 of a bottle body 1 shown in FIG. The holding mold 10 of the reform 10a has a structure in which the mold is closed at the upper part. Reference numeral 13 denotes a recess forming die for forming the recess 3 on the upper side surface of the bottle body 1, which is provided on one side of the cavity 12 at a portion forming the upper side surface of the bottle body 1. The concave mold 3 is a hollow one formed by joining a pair of halves in a block shape, and is fitted into a window hole provided in one of the divided dies 11a to protrude into the cavity 12. . The upper and lower surfaces and the vertical wall surface facing the cavity 12 by the projection are located on the upper side surface of the cavity 12 as convex surfaces for forming the upper and lower wall surfaces 7 and 8 and the vertical wall surface of the concave portion 3. Openings 15, 15 of an internal space 14 are formed in the upper and lower surfaces of the concave mold 3, respectively, and the concave portions 7a, 8a are formed in the internal space 14 at L-shaped ends. Pair of upper and lower forming levers 1 having projections 16
The rear ends of the first and second shafts 17 and 17 are pivotally attached to each other so that the protrusions 16 and 16 project in and out of the cavity 12 through the openings 15 and 15 and the rear ends of the first and second shafts 17 and 17 are rotatably mounted. is there. A pressing member 18 is housed in the internal space 14 on the rear surface of the forming levers 17, 17 by connecting to both forming levers 17, 17 by link plates 19, 19.
The inner surface of the pressing member 18 is formed into a tapered surface so as to be in contact with the rear surfaces of the forming levers 17 and 17 so as to maintain a protruding state, and the link plates 19 and 19 are attached to the central portion and the bent portions of both forming levers. It is. A split mold 11 is provided on the back of the pressing member 18.
An operation member 20 of a long plate body provided with a movable space between a and the template 21 is provided by bolts. Both ends of the operation member 20 are connected to pistons 23 of the air cylinders 22 mounted on the template 21, and the pressing members 18 are pressed by the air cylinder.
Are reciprocated together with the operation member 20. In the drawing, reference numeral 24 denotes an extension rod, and reference numeral 25 denotes a mold clamping piston. In the blow mold having the above-mentioned structure, as shown in FIG.
The mold is closed in a state in which the molds 6 and 16 are housed in the concave mold 3, and after the mold is closed, blow molding of the preform 10a located at the center of the cavity 12 is performed. This shaping is performed both by the axial stretching to the bottom of the mold by the stretching rod 24 and by air blowing performed almost simultaneously. As shown in FIG. 3, the preform 10a expands to the full cavity by the axial stretching and the air blow to be molded into the thin bottle body 1, and at the same time, one side of the upper side surface of the bottle body 1. Is recessed into the bottle body 1 by the convex surface of the concave mold 3 and is formed into the concave portion 3 (see FIG. 5) for attaching a handle, which is composed of upper and lower wall surfaces 7, 8 and a vertical wall surface. Following the molding of the bottle body 1, before the resin on the upper wall surface 7 and the lower wall surface 8 is completely solidified, the molding protrusions 16, 16 are opened and closed as shown in FIG. , 15 project from the molding projections 16, 16
Partially displaces the upper wall surface 7 and the lower wall surface 8, respectively, to form recesses 7a, 8a. The protrusions of the molding projections 16 are as follows.
This can be easily achieved by pushing the pressing member 18 inward via the operating member 20 by the forward movement of the operating member 20 by the air cylinders 22, 22. The pressing member 18 is pushed inward by the forward movement of the operating member 20,
The link plates 19 press the bent portions of the pair of forming levers 17. The forming levers 17, 17 are pivoted up and down about the shaft attachment portion at the rear end, and are formed at the leading ends of the forming projections 16, 1, 1.
6 protrudes from the openings 15, 15 to form recesses 7 a, 8 a in the upper wall surface 7 and the lower wall surface 8. The pressing member 18 is pushed until the inner tapered surface comes into contact with the rear surface of the molding levers 17, 17, and pushes the molding levers 17, 17 until the resin on the upper wall surface 7 and the lower wall surface 8 is completely solidified. Press and maintain. Due to the solidification of the resin, the recesses 7a, 8a thus formed maintain their shape even after the molding projections 16, 16 are removed. After the blow molding is completed, the air cylinder 2
When the operation member 20 is moved backward by the operations of the steps 2 and 22,
The pressing member 18 is returned to the original position. As a result, the pressing force on the forming levers 17, 17 is removed, and the bent portions are pulled by the link plates 19, 19, and the forming levers 17, 17 are pulled back to their original positions with the rear end portions as fulcrums, and the forming protrusions are formed. 16, 16 are concave molds 13
Immerse yourself in the interior. Due to this immersion, the molding projections 16, 16
The handle mounting recess formed in the bottle body 1 does not become an obstacle when the mold is released from the recess forming die 13, and therefore,
The mold opening of the mold 11 can be performed at the parting of the pair of split molds 11a and 11b to release the bottle body 1. Although this embodiment shows a blow mold in the case of injection stretch blow molding, in the case of stretch blow molding which is generally called a cold parison method, the blow mold is different from that of the embodiment. Is facing downward,
The holding mold 10 of the preform 10a has a structure in which the mold is closed at the lower part. Further, a plurality of cavities 12 may be provided. As described above, the protrusion 1 for forming the recess is provided at the tip.
A pair of L-shaped forming levers 17, 17 having 6, 6
The rear end is pivotally mounted on the upper and lower surfaces of the concave forming die 13 so as to protrude and retract from the upper and lower surfaces of the concave forming die 13, and is provided vertically in the concave forming die 13. , 1
Pressing member 18 and link plate 1 movably provided on rear surface 7
In the blow mold 11 of the present invention for forming the recesses 7 a, 8 a on the upper and lower wall surfaces 7, 8 of the recess formed by the recess forming die 13, the pressing member 18 is slightly connected.
With the advance / retreat stroke, the molding protrusions 16 can be easily moved in and out. The forming levers 17, 17 are rotated to project the forming projections 16, 16, and the pressing members 18 are pressed against the forming levers 17, 17 to press the forming levers 17, 17 so that the recesses 7 are formed.
a and 8a can be formed, so that even when the resin forming the upper and lower wall surfaces is solidified to some extent, the recesses 7a and 8a can be reliably formed, and the reaction force during the molding is reduced by the pressing member 1.
8, the recesses 7a, 8a are not easily deformed due to the return of the forming levers 17, 17, and a pair of upper and lower forming levers 1 are formed inside the recess forming die 13 as a recess forming device.
Since it is only necessary to connect the pressing members 18 with the pressing members 18 by the link plates 19 and 19 and to pivotally mount the forming levers 17 and 17, it is easy to assemble, and the connection with a driving source such as an air cylinder is also operated. Since it can be easily performed through the members, it can be used not only as an injection stretch blow molding but also as a blow mold of a cold parison method.
As a blow mold for a biaxially stretched bottle with a handle, the manufacturing cost can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view of a main part of a blow-molded biaxially stretched bottle according to the present invention in a closed state of a blow mold. FIG. 2 is a sectional view taken along line AA of FIG. FIG. 3 is a longitudinal sectional view of a main part when the bottle body is formed. FIG. 4 is a longitudinal sectional view of an essential part when a locking recess is formed. FIG. 5 is a longitudinal sectional side view of a known biaxially stretched bottle with a handle. DESCRIPTION OF SYMBOLS 1 Bottle main body 2 Handle 3 Recess 5 for attaching handle 5 Upper wall 6 of recess 5 Lower wall 5a, 6a of locking recess 11 Blow mold 12 Cavity 13 Recess forming mold 15 Opening 16 Forming protrusion 17 forming lever 18 pressing member 19 link plate 20 operating member 22 air cylinder

Claims (1)

(57) [Claim 1] An openable mold for forming a cavity of a bottle body by a pair of split molds, and a metal mold on one side of a portion of the cavity forming an upper side surface of the bottle body. A block-shaped concave forming mold for attaching a handle, which is fitted and protruded from the mold side surface, and an L-shaped projection having a concave forming protrusion at the tip, and the forming protrusions are formed on the upper and lower surfaces of the concave forming mold. So that it appears
A pair of upper and lower forming levers provided in a concave forming mold with a rear end pivotally mounted on a shaft, and a pressing lever movably provided on the back of the forming lever and connected to both forming levers by a link plate. A blow mold for a biaxially-stretched bottle with a handle, comprising: a member; and an operating member on a side surface of a mold provided laterally on the pressing member.