JP2587401B2 - Local diameter reduction method for glass containers - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a local diameter reduction direction of a glass container, for example, to improve the heat retention of a glass container constituting a main body of a water bottle of a magic bottle. Therefore, it is used as a local squeezing means for forming a small squeezed portion at the neck of the glass container having a relatively large body diameter.

[Conventional technology]

For example, as a method of forming a glass container or the like constituting a hot water storage device main body of a magic bottle, a blow-and-blow type rotating blow molding method is known. Hereinafter, an outline of the molding operation will be described with reference to FIG. FIG. 3A is a front view illustrating the entire structure of the rotary blow molding machine. In the figure, (1) is a feeder of molten glass (2) continuing from a glass melting furnace, which includes a plunger device composed of a rotating cylinder (4) and a plunger (3), and an orifice (5) opened below the plunger device. The orifice (5) has a shear blade (6) below the orifice (5).
Is arranged. (8) Shear blade (6)
This is a chute which feeds the gob (7) sheared by the above to the blow molding machine. Rotary blow molding machine, chute (8)
A disk gob (7a) comprising a press head (9) and a suction head (10) arranged on the discharge side of a gob (7), and a revolving orbit about a machine center (15) as a rotation center. Moving turntable (13),
A blowing section (14) consisting of a working table (11) with a blow head (16) and an orifice plate (12) arranged vertically at the tip of the turntable (13); A two-part molding metal fitting (17a) (17b) that is supported below the table (11) so as to be openable and closable with the center of the orifice plate (12) aligned with the axis (see FIG. 3G).
It is composed of

Hereinafter, the method of forming the glass container (7d) will be described with reference to FIGS. 3A to 3J.

FIG. 3A A glass (2) melted in a method furnace (not shown) is guided by a feeder (1) and moves up and down in a plunger (3).
By the orifice (5). The glass (2) is sheared by the shear blade (6) to form a high-volume glass gob (7) having a predetermined volume. The gob (7) slides on the chute (8) and is set on the press head (9).

FIG. 3B When the gob (7) is set, the press head (9)
Rises, and the gob (7) is pressed between the suction head (10) and the press head (9) to become a disk gob (7a).

FIG. 3C The disk gob (7a) is sucked and held by the suction head (10), and is transferred onto the working table (11) by the horizontal rotation of the suction arm (10a) about the axis (10b). Is done.

Fig. 3 Suction head (10) is disk gob (7a)
When the transfer operation on the working table (11) is completed, the negative pressure suction is stopped.

As a result, the disk gob (7a) is set at a predetermined position on the working table (11).

FIG. 3E The disk gob (7a) in the semi-molten state hangs down by the vehicle from the hole of the orifice plate (12) provided in the working table (11), and at the same time the blow head (16) Coming down.

FIG. 3F The working table (11) starts rotating and blow head (16) in the deformed disk gob (7a)
, The blowing air for the primary molding is blown, and the molding of the parison (7b) starts.

FIG. 3G When the molding of the parison (7b) is completed, the molding dies (17a) (17b) that have been opened to the left and right begin to close.

FIG. 3H When the molding dies (17a) and (17b) are completely closed,
Blowing air for secondary molding is blown into the parison (7b), and the valve (7c) is molded while the working table (11) rotates.

Fig. 3 When the molding of the valve (7c) is completed, the molding die (17
a) (17b) opens left and right, and the blow head (16) rises.

Fig. 3 J The molded valve (7d) is a disk cutter (18)
Is separated from the moil (7e) at the upper surface of the orifice plate (12), and is sent out as a glass container (7d) to the lehr by a conveyor (not shown). Moils (7e) separated from the valve (7d) are collected as cullet and reused.

[Problems to be solved by the invention]

By the way, when the glass container (7d) is, for example, a water bottle main body of a magic bottle, in order to improve heat insulation, a small-diameter neck is attached to the glass container (7d) having a relatively large body diameter. It is necessary to form a narrowed portion. Therefore, when the neck diameter of the molding dies (17a) and (17b) is narrowed down, the difference between the diameter of the body of the glass container (7d) and the neck diameter is large, so that the glass container (7d) can pass through the small diameter neck. You must use a small parison (7b)
Not only is the increase in capacity of the glass container (7d) restricted, but also the thickness of the body becomes extremely thinner than the thickness of the neck. More specifically, when a molding die having such a local narrowing portion is used, when the molding dies (17a) and (17b) are closed, the squeezing protrusion of the molding die is used. The parison (7b) is caught and the smooth inflow of air for secondary blowing into the main part of the glass container (7d) located below the neck is hindered, and as a result, the thickness of the neck is increased, An extremely non-uniform thickness distribution glass container having a thin body portion is formed, and such a glass container naturally has low strength, and its commercial value is impaired.

In order to solve the above-mentioned problems, for example,
In the publication, as shown in FIGS. 4 and 5, there is provided a rail-shaped narrowing member (19) whose distance from the center of the parison (7c) gradually decreases along the path of the parison (7c). It has been advocated. However, in this method, before hanging the parison (7c) into the molding dies (17a) (17b), the narrowing member (19) is attached to the neck of the parison (7c) from one side under the working table (11). ), The parison (7c) may be subject to torsional deformation due to one-way pressing under the suspended support.

Japanese Patent Publication No. 49-14122 discloses a squeezing member for narrowing a parison neck from both sides simultaneously with closing of the mold in conjunction with the closing operation of the molding die. However, in this method, it is necessary to keep the forming mold in a half-open state while the parison rotates at least one time, which makes it difficult to adjust the drawing time and also increases the forming metal. The structure of the mold is also complicated.

A first main object of the present invention is to propose a means for blow molding a glass container having a uniform thickness distribution and a reduced diameter portion. A second object of the present invention is to cause the parison to hang down under its own weight in the molding die, and then locally press the parison from the outside by a narrowing-down pressing member inserted from the outside of the molding die. It is to propose a blow molding means for forming a reduced diameter portion having an aperture.

[Means for solving the problem]

As a means for solving the above-mentioned problems, the present invention is a method of manufacturing a glass container by a blow-and-blow method, which is rotated in a closed molding die after the blowing of primary blowing air is completed. While the secondary blow air is being blown into the parison, a narrowing pressing member is fitted through a slit opened at the narrowing position of the glass container, and the narrowing pressing member is fitted to the outside of the parison facing the portion. The present invention provides a method for locally reducing the diameter of a glass container in which a tip portion of a glass container is press-fitted to form a narrowed portion having a diameter smaller than the inner diameter of a molding die at the narrowed position.

[Action]

After the blowing of the primary blowing air is completed, the tip of the pressing member for narrowing is pressed against the outside of the rotating parison which is suspended in the molding die under the blowing of the secondary blowing air. A small diameter reduced diameter portion is formed at the narrowing position.

〔Example〕

FIG. 1 is a schematic front view of a rotary blow molding machine that can be used in the present invention, and FIG. 2 is an explanatory view of the operation timing of a pressing member in the method of the present invention. In the following description, the same components as those in FIGS. 3A to 3J are denoted by the same reference numerals, and the description of the same items will not be repeated.

As shown in FIG. 1, a slit (20) is formed in the upper part of one molding die (17b) in accordance with the position of the neck (26) of the parison (7c).
A narrowing pressing member that moves substantially horizontally back and forth, for example, a distal end portion of a pressing roller (21) is fitted therein. Before blowing the secondary blowing air, the tip of the pressing member (21) for narrowing closes the slit (20) of the molding die (17b) and holds it at a position where it does not protrude inside.
The pushing roller (21) is made of a metal material such as stainless steel or brass, or a heat-resistant material such as ceramic or fluororesin, and is pushed into contact with the outer peripheral surface of the parison (7c) where the small-diameter neck (26) is formed. The outer peripheral surface of the roller (21) is mirror-finished. The pushing roller (21) used in this embodiment is a flat rotating disk made of brass. The pushing roller (21) is a prismatic lever (22) supported by a bearing (23) so as to be able to move back and forth. ) At the tip of the neck (26) by attaching via pin (27)
Forward and backward according to the narrowing method of the parison (7
The pressing member for narrowing down freely rotates horizontally by contacting the outer peripheral surface of c). Incidentally, (24) is a rotatable cam follower attached to the rear end of the lever (22) via a pin (28), and (25) is a vertical direction in which the cam follower (24) fits. Inclined cam groove (25a)
It is an end face cam provided with. This end cam (25) is
When the lever (22) is linearly moved vertically in the direction indicated by the arrow, a horizontal reciprocating motion indicated by an arrow Ho occurs in the lever (22). Therefore, when the lever (22) is moved in the forward direction through the elevation of the end cam (25), the pushing roller (21) mounted on the front end of the lever (22) advances in the slit (20) and moves to the molding die ( 17a) Abuts the upper outer peripheral surface of the parison (7c) which hangs in its own weight in (17b), and presses the neck (26) of the parison (7c) while rotating. On the contrary, when the lever (22) is moved in the retreating direction through the lowering of the end cam (25), the pushing roller (21) retreats in the slit (20). As a result, the pushing roller (21) separates from the outer peripheral surface of the parison (7c), and the drawing operation ends.

Hereinafter, a specific example of the present invention will be described based on a blow example of a hot water storage device main body of a magic bottle.

As shown in FIG. 2, after the blowing of the primary blowing air is completed, the molding dies (17a) and (17b) which have been opened to the left and right are closed, and the molding dies (17a) and (17b) are closed. Air for secondary blowing is blown from a blow head (16) into a parison (7c) that is suspended and rotated by its own weight in a molding die (17a) (17b). While the secondary blowing air is being blown into the parison (7c), the pushing roller (21) is moved toward the neck (26) of the parison (7c). When the outer periphery of the pushing roller (21) comes into contact with the outer peripheral surface of the parison (7c), the pushing roller (21) is rotated by friction, and the pressing force under this rotation causes the neck (26) of the parison (7c) to rotate. The molding die (17
A narrowed portion having a smaller diameter than the inner diameter of b) is formed. When the formation of the narrowed portion and the formation of the hot water storage unit are completed, the blowing of the secondary blowing air is stopped, and the pushing roller (2
With the 1) retracted, open the molding dies (17a) and (17b) to the left and right, and raise the blow head (16). Thereafter, the moil (7d) is removed from the state of the formed hot water storage unit (7d).
e) is separated and one cycle of blow molding is completed.

As described above, the present invention has been described based on the specific example of forming the small-diameter neck portion on the upper part of the water bottle body of the magic bottle, but the scope of the present invention is to be interpreted in a limited manner based on the above description. Instead, it is possible to form a small diameter narrowing portion at a desired position of the parison by selectively adjusting the operating position of the pressing member. A pressing member other than the above-mentioned pressing roller, which does not cause abrasion due to the narrowing portion when abutting on the outer peripheral surface of the parison, can be used in the same manner.

〔The invention's effect〕

According to the method of the present invention, a reduced diameter portion can be formed at a desired portion of a parison without extremely uneven thickness distribution of a product. Therefore, a decrease in strength and a decrease in productivity due to a lack of wall thickness, which has been a problem in the formation of a diameter-reduced blow head by the conventional blow-and-blow method, can be reliably avoided. We can make a product with weight.

[Brief description of the drawings]

FIG. 1 is a schematic front view of a rotary blow molding machine that can be used in the present invention, and FIG. 2 is an explanatory view of the operation timing of a pressing member in the method of the present invention. FIG. 3 is an explanatory view of the general structure and operation of a conventional blow molding machine, FIG. 4 is a schematic plan view of a conventional drawing device, and FIG. 5 is a front view thereof. (7c): Parison, (17a) (17b): Mold for molding, (16): Blow head, (20): Slit, (21): Pressing member (pressing roller) for drawing (Pressing roller) ( 26) ... neck.

Claims (1)

(57) [Claims] In the manufacture of a glass container by blow-and-blow type blow-molding, after the blowing of primary blow air is completed, a secondary parison is rotated in a closed molding die. While the blowing air is being blown in, the pressing member for narrowing is fitted through a slit opened at the narrowing position of the glass container, and the leading end of the pressing member for narrowing is pressed into the outside of the parison facing the portion. A method of locally reducing the diameter of a glass container, wherein a narrowed portion having a diameter smaller than the inner diameter of the molding die at the narrowed position is formed.