JP3118277B2 - Manufacturing equipment for thin-walled hollow containers - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a manufacturing equipment of thin hollow container having integrally a tubular portion at least one end of the thin body portion and said thin trunk portion.

[0002]

2. Description of the Related Art A container of this kind is used as a container for storing a drug solution or blood in the medical field. It is required that the solution be slowly poured out and not remain in the container. For this reason, it is required that the thickness of the body be extremely thin, and that the container itself deforms spontaneously due to the outflow of the stored drug solution and blood, and that the container be dropped naturally without supplying air into the container. Have been. Further, the inlet or outlet of this type of container is provided with a tubular portion for connecting to another container, a flexible pipe, or the like. Since this tubular part needs to be free from leakage of chemicals and blood from the connection part and invasion of various bacteria from the outside,
It is necessary to increase its rigidity. For this reason, it is desired that the thickness of the tubular portion be as large as possible.

Heretofore, as a method for producing such a thin hollow container, there is disclosed a method disclosed in Japanese Patent Application Laid-Open No. 60-23922 filed by the present applicant.
No. 2 discloses a method described below.

[0004] After disposing a heated and melted parison between the split molds, the mold is closed. First, the parison is clamped by a sliding mold protruding inward of the split mold, and an upper end tubular portion is formed. And a lower end tubular portion, and the parison is sealed. Then, a pressurized fluid is introduced into the parison to inflate the parison, the parison is made thinner, and the split mold is closed to form a body of the thin hollow container.

[0005]

In the above prior art, as described above, since the thin body is thinned only during the process of expanding the parison, the thinning is naturally limited. More specifically, as described above, when the thickness of the tubular portion is increased in order to increase the rigidity of the tubular portion, the thickness of the body portion is increased accordingly. Conversely, when the thickness of the parison is reduced in order to reduce the thickness of the body, there is a dilemma that the thickness of the tubular portion is reduced accordingly. For this reason, there is a problem that it is difficult to reduce the thickness sufficiently to meet the above-mentioned needs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art. Even if the thickness of the tubular portion is the same as that of the conventional example, the thin wall portion can be made sufficiently thin. it is an object to provide a manufacturing equipment of hollow vessel.

[0007]

Means for Solving the Problems To achieve the above object,
Therefore, the thin hollow container manufacturing apparatus of the present invention , a thin body,
An apparatus for manufacturing a thin-walled hollow container integrally having a tubular portion at at least one end of the thin-walled body, wherein a main body mold having a cavity for forming the thin-walled body and an upper portion having at least one of the cavities for forming the tubular portion are provided. A pair of split molds formed by a mold and a lower mold, wherein the upper mold and the lower mold close the mold of the main mold when closing the set of split molds. The main body mold is connected to the main body mold via a link mechanism so that the molds are closed and then moved in directions away from each other.

[0008]

The parison arranged between a pair of split molds with the mold opened is sandwiched between an upper mold and a lower mold, and the upper mold and the lower mold are moved in a direction away from each other. Stretch Parison. As a result, the thickness of the holding portion by the upper mold and the lower mold of the Parisun is held for the portion serving as a body portion of the container is stretched wall thickness is reduced. Thereafter, the main body mold is closed, and the parison is expanded by blow molding to form a thin body. As a result, the wall thickness of the body parison is further reduced, and a sufficiently thin body and a tubular part having sufficient rigidity are formed.

[0009]

An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a plastic container for chemicals (hereinafter, referred to as a "thin hollow container") 1 which is a thin hollow container manufactured by the thin hollow container manufacturing apparatus of the present invention. As shown in FIG. 1, a thin-walled hollow container 1 is provided with a flat thin-walled body portion 2 having a very thin thickness, and is connected to upper and lower portions of the thin-walled body portion 2 via shoulders 3a and 3b in the drawing. It is composed of thick tubular portions 4a and 4b. Each tubular part 4
As described above, a and 4b are required to be as rigid as possible and not to be deformed. Conversely, the thin body 2 is required to have low rigidity and be easily deformed. Again, the thickness of each of the tubular portions 4a and 4b is large, and the thickness of the thin body portion 2 needs to be as thin as possible compared to the respective tubular portions 4a and 4b.

[0011] Next, a description will be given of one embodiment of an apparatus for manufacturing a thin-walled hollow container of the present invention.

FIG. 2 is a plan view of one of the split molds as viewed from the surface on which the cavity is formed. However, a second fixing member described later is omitted.

[0013] One of the main mold. 5a, shoulder portion 3a, has a cavity 6a for molding a thin-wall barrel portion 2 including 3b, each of the illustrated upper portion and illustrated lower portion of the body mold 5a each tubular An upper mold 7a and a lower mold 8a having cavities 9a and 10a for molding the parts 4a and 4b are provided.

As shown in FIG. 3, the molten parison 23 is extruded from an extrusion head 24 of an extruder (not shown) in a state where the divided molds are opened, and the mold is closed after being arranged between the divided molds. First, the pair of upper molds 7a and 7b and the pair of lower molds 8a and 8b are closed and the paris 23 is clamped.

Next, the upper molds 7a, 7b and the lower molds 8a, 8b are moved in directions away from each other (up and down directions in the figure), and the paris 23 is stretched. As a result, the parison 23 is connected to the upper molds 7a and 7b.
And the portion between the lower molds 8a and 8b,
The portion between the upper tubular portion 4a and the lower tubular portion 4b shown in FIG. 1 is stretched to reduce its thickness.

Further, the mold closing is advanced, and the upper molds 7a, 7b and the lower molds 8a, 8b are separated from each other to a position where they do not interfere with the pair of main body molds 5a, 5b.
After closing the main body dies 5a and 5b, a pressurized fluid is introduced into the paris 23 to expand the paris 23, and the shoulder 3
The thin body 2 including the parts a and 3b is blow-molded.

At the time of the blow molding, the Paris 23
As described above, since the wall thickness is reduced by stretching in advance, the wall thickness is further reduced by this blow molding, and the thin body portion 2 having a significantly thinner thickness than the conventional example is formed. can do.

Since one set of split molds has the same configuration, the following description will focus on one split mold. FIG. 4 is a perspective view showing a portion of one main mold 5a, one upper mold 7a and one lower mold 8a of a set of split molds.

One of the main body dies 5a attached to the movable plate of the mold clamping device (not shown) has a projection 15a at the center thereof, and the shoulders 3a and 3b are provided on the front surface of the projection 15a.
Cavity 6 for molding the thin body portion 2 (see FIG. 1) including
a is formed.

Here, the upper dies 7a, 7 of the present embodiment are described.
b and the lower dies 8a and 8b are moved in a direction in which the pair of split dies are separated from each other after closing the dies prior to closing the main dies 5a and 5b when closing the pair of split dies. Will be described.

Plate-shaped first fixing members 11a are fixed to the central portions of both side surfaces of the main body mold 5a, and the first fixing members 11a are provided with shafts 16a, respectively. One end of the first arm 12a and one end of the second arm 13a are sequentially rotatably supported by the shafts 16a, respectively. The other end of each first arm 12a is pivotally connected to a shaft 18a protruding from a support plate 17a fixed to a side surface of an upper mold 7a having a cavity 9a for forming a tubular portion 4a. Supported. On the other hand, the other end of each second arm 13a is rotatably supported by a shaft 18b protruding from a support plate 17b fixed to the side surface of the lower mold 8a. The second fixing members 14a and 14b
A plate for fixing the two plate members 20a and 20b (vertically cut away from FIG. 4 so that 20b is omitted since FIG. 4 shows the second fixing members 14a and 14b) and a central portion thereof. It is formed in an H shape from the body 20c, and is fixed to the base by means (not shown) to form an immovable fixed point.
Pins 21a and 21b are protruded from upper and lower ends of the plate body 20a of the second fixing members 14a and 14b. Each of the first arm 12a and the second arm 13a is formed with a guide hole 19a, 19b extending in the longitudinal direction thereof.
A pair of pins 21a and 21b protruding from both end portions of a are slidably fitted respectively. Although not shown, the other ends of the second fixing members 14a and 14b are formed so as to be able to expand and contract when an unexpected load is applied.

Next , the operation of this embodiment will be described with reference to FIGS.
This will be described with reference to FIG. With the mold open,
The pair of left and right main body molds 5a and 5b are separated from each other by a maximum distance, and a pair of pins 2 protruding from both ends of the plate 20a.
Reference numerals 1a and 21b move relatively to the leading end portions of the guide hole 19a of the first arm 12a and the guide hole 19b of the second arm 13a, respectively. For this reason, the upper mold 7
a and the lower mold 8a are in a state where they have moved to a portion where the distance between them is the shortest, that is, the position A in FIG.

In the above-described opened state, the parison 23 is connected to the pair of upper dies 7a and 7b and the pair of lower dies 8a and 8b.
After the mold is closed, the mold closing is started, and the parison 23 is sandwiched between the pair of upper molds 7a and 7b and the pair of lower molds 8a and 8b to form the upper tubular portion 4a and the lower tubular portion 4b. I do. This allows the Paris 23
Will be sealed.

When the mold closing is further advanced, a pair of pins 21a and 21b at both ends of the plate 20a slide in the guide holes 19a of the first arm 12a and the guide holes 19b of the second arm 13a, respectively. To relatively move to the first fixing member 11a side. Therefore, both arms 12
The pair of upper dies 7a and 7b and the pair of lower dies 8a and 8b are separated from each other in the vertical direction in the drawing while holding the paris 23 therebetween. , To the position B shown in FIG.
The position B corresponds to the protrusion 15 of the pair of main body molds 5a, 5b.
a and 15b above the upper and lower surfaces in the figure, and do not interfere with the protruding portions 15a and 15b of the pair of main body molds 5a and 5b during the subsequent mold closing progress. Thereafter, by further closing the molds, the pair of upper molds 7a, 7b and the pair of lower molds 8a, 8b are connected to the respective projecting portions 15a, 15 of the pair of main body molds 5a, 5b.
The position moves to a position abutting on the upper surface and the lower surface of FIG. b, that is, a position C in FIG. 5, and complete mold closing is performed. In this completely closed state, a pressure fluid is introduced into the paris 23 by a supply means (not shown), and blow molding is performed.
The thin hollow container 1 as shown in FIG.

The smooth movement of the pair of upper dies 7a, 7b and the pair of lower dies 8a, 8b described above to the respective positions A, B, C can be achieved by appropriately setting the guide holes 19a, 19b. Needless to say, this can be achieved.

Further, the link mechanism described above is not limited to that of the above-described embodiment, but may be, for example, a known Scott Russell mechanism.

[0027]

Since the present invention is configured as described above, the following effects can be obtained.

Even if the thickness of the tubular portion is set to be as large as the rigidity as in the conventional example, a thin-walled hollow container in which the thickness of the thin-walled body portion is sufficiently smaller than that of the conventional example can be manufactured.

[Brief description of the drawings]

FIG. 1 is a perspective view of a chemical liquid plastic container manufactured by a thin hollow container manufacturing apparatus of the present invention.

FIG. 2 is a plan view of one of the divided dies of the apparatus for manufacturing a thin-walled hollow container according to the present invention , as viewed from a surface on which a cavity is formed.

FIG. 3 is a schematic side view of an apparatus for producing a thin hollow container according to the present invention .

[4] which is one perspective view of a split mold for thin-walled hollow container manufacturing apparatus of the present invention.

FIG. 5 is an explanatory view showing the positional relationship of one of the split molds of the apparatus for manufacturing a thin hollow container of the present invention when the mold is closed.

[Explanation of symbols]

Reference Signs List 1 plastic container for chemical liquid 2 thin body 4a, 4b tubular part 5a, 5b main body mold 6a, 6b, 9a, 10a cavity 11a first fixing member 12a, 12b, 13a, 13b arm 14a, 14b second fixing member 15a, 15b Projection 19a, 19b Guide Hole 20a, 20c Plate

Claims (1)

(57) [Claims] 1. A thin body and at least one of the thin body.
Apparatus for manufacturing thin-walled hollow containers with a tubular section at one end
And a body metal having a cavity for molding the thin body portion
A mold and at least one of the cavities for molding the tubular portion
Constituted by an upper mold and a lower mold having
An upper mold and a lower mold comprising a set of split molds
When closing the pair of split molds, the main body mold is closed.
Before closing the mold, move away from each other after closing the mold
Connected to the main body mold via a link mechanism so as to move.
Manufacturing apparatus for a thin-walled hollow container characterized by being connected
Place.