JPS6129605Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a stretch-blown polyethylene terephthalate container, and more particularly to a stretch-blown polyethylene terephthalate container having a convex portion on the bottom for engaging a positioning claw. .

(Prior Art) Stretch-blown polyethylene terephthalate containers (hereinafter simply referred to as containers) are characterized by their transparency, strength,
It has attracted attention for its excellent properties such as impact resistance and gas barrier properties, and has recently been commercialized.

When this container is used as a product, it is often printed or labeled on the outside of the body. By the way, the body has two so-called parting lines (see 1 in Figure 1) formed by gaps between split molds during container manufacturing, so these parting lines are used during printing. It is desirable to avoid.
In addition, labels are often pasted on a predetermined flat surface of the body (see 2 in FIG. 1).

Therefore, before printing or pasting the label, the method described in Japanese Utility Model Publication No. 37-19200,
Alternatively, positioning is performed by a method as shown in FIG. In the case of FIG. 2, the bottom 4 of the container 3
An engaging portion 7 that engages with a pawl 6 provided at the tip of a rotating member 5 that can rotate concentrically with the container 3 is provided at a predetermined angular position in the circumferential direction with respect to the parting line.

The rotating member 5 is driven by a positioning motor such as a stepping motor 8, and the stepping motor 8 is controlled so that the claw 6 stops at a predetermined position. Therefore, the engaging part 7 of the container is connected to the claw 6 of the rotating member.
and press the mouth part with a rotatable holding member 9 via a spring (not shown),
When the stepping motor 8 is stopped, the parting line 1 of the container 3 is stopped at a predetermined angular position in the circumferential direction, and positioning is performed.

Conventionally, as an engaging part of the container, a concave part as shown in FIG. 1 of Japanese Utility Model Publication No. 37-19200, or a concave part 1 as shown in FIGS.
0 is used.

As shown in FIG. 3, the recess 10 consists of a pair of fan-shaped recesses extending in the circumferential direction and provided in centrally symmetrical positions. The bottom of the fan shape gradually becomes deeper from one end 10a to the other end 10b in the circumferential direction. Therefore, the pawl 6 enters from the end 10a, turns in the direction of the arrow, and engages with the end 10b, as shown in FIG. Such a recess 10
is formed simultaneously with the formation of the container by stretch-blow molding a bottomed parison using a mold having a bottom mold having a convex portion having a shape corresponding to the recessed portion 10.

However, the conventional engaging portions as described above have the following problems. In other words, the container can only be rotated in one direction, the direction of the arrow in FIG.
There are two types of printing presses: clockwise and counterclockwise.
Therefore, it cannot be applied to either one of the printing machines. In order to be able to be applied to any printing machine, different types of recesses (10a section is shallow, 10b is deep, and 10a section is 10 deep) are required.
It is necessary to make two types of containers (those with shallow part b), which poses the problem of being labor-intensive and uneconomical.

In addition, the part of the parison corresponding to the concave part 10 contacts the bottom mold (corresponding convex part of the bottom mold) and cools down before other parts, so it becomes difficult to elongate and causes uneven thickness (see FIG. 5). Furthermore, forming convex portions on the bottom mold requires more effort and costs than forming concave portions.

(Problems to be Solved by the Invention) The main purpose of the present invention is to provide a stretch-blown polyethylene terephthalate container that can be reliably placed on a positioning device in either clockwise or counterclockwise rotation. .

Another object of the invention is to provide a stretch-blown polyethylene terephthalate container of the above type with upright stability, which can be manufactured at relatively low cost.

(Means for Solving the Problems) The stretch-blown polyethylene terephthalate container of the present invention has a bottom portion provided with an annular protrusion forming a ground plane on the periphery. A pair of convex portions having linearly extending side portions for engaging the positioning claws on the inner side of the portion are provided at center-symmetrical positions, and the wall thickness of the convex portions is equal to the thickness of the convex portions. It is characterized in that the thickness of the convex portion is approximately equal to the thickness of the other portion of the bottom portion in the circumferential direction, and the bottom surface of the convex portion is located on or inside the ground plane.

(Function) The stretch-blown polyethylene terephthalate container of the present invention is provided with a pair of convex portions at centrally symmetrical positions on the bottom for engagement with positioning claws. Therefore, as shown in FIG.
e' can be engaged with any of the side parts 13e
When engaged, the container rotates clockwise and side 1
When engaged with 3e', the container rotates counterclockwise. Therefore, the container of the present invention can be applied to a positioning device in either a clockwise or counterclockwise direction of rotation.

Furthermore, since the side portions of the convex portions 13 extend linearly, the positioning claws can be reliably engaged with the side portions.

To form a convex part on a bottom mold, it is sufficient to simply engrave a concave part corresponding to the convex part, so the manufacturing cost of the bottom mold is lower than that of a bottom mold for forming a concave part. Since the thickness of the convex portion is approximately equal to the thickness of the other portion of the circumferential bottom of the convex portion, the material cost is also relatively low compared to a case where the convex portion is solid. Therefore, the container of the present invention can be manufactured at relatively low cost.

The bottom of the container of the present invention is provided with an annular protrusion that forms a ground plane on the periphery, and the bottom surface of the convex portion is located on or inside the ground plane, so the container of the present invention can be properly adjusted by itself. It has vertical stability.

(Example) The present invention will be described below with reference to drawings showing examples.

1 and 7 show the container of the present invention, in which an annular protrusion 11 is provided on the periphery of the bottom 4 to ensure upright stability, and its apex line 11a is A ground plane 12 (a virtual plane passing through the circumference formed by the apex line 11a) is formed. A pair of opposing protrusions 13 extending in the radial direction are formed on the inner side 4a of the annular protrusion 11 at symmetrical positions with respect to the center of the bottom. Bottom annular protrusion 1
As shown in FIG. 1, the inner side portion 4a of 1 is a substantially spherical recess. Therefore, the convex portion 13
As shown in FIG. 8, the depth gradually increases from the peripheral side 13b toward the center side 13a. The bottom surface 13c is almost flat,
A small protrusion 13d, which is a trace of an air vent hole, is attached to a portion near the center side portion 13a. The convex portions 13 are formed by stretch-blow molding a bottomed parison in a mold (not shown) having a bottom mold in which a concave portion having a shape corresponding to the convex portions 13 is formed. At this time, the bottom of the parison comes into contact with parts of the bottom mold other than the recesses first, so unless the air remaining in the recesses is discharged, the remaining air will prevent the formation of the desired shape of the projections 13. For this reason, a small hole for air release is provided at the bottom of the recess. Note that the bottom surface 13c (including the small protrusion 13d) does not protrude outside the ground plane 12.
Necessary for upright stability. The side portion 13e of the convex portion 13 is a plane that extends linearly and is substantially parallel to a plane passing through the axis of the container 3 in order to ensure engagement with the positioning pawl 6. As mentioned above, the convex part 13 is formed by press-fitting the bottom of the parison into the corresponding concave part of the bottom mold during stretch blow molding, and at this time, the part of the parison corresponding to the convex part 13 is more also laterally contacts the bottom mold surface (i.e. the corresponding recess). Therefore, the convex portion 13
Since it is not cooled by the bottom mold surface during the forming process, it extends sufficiently, and therefore the thickness of the convex part 13 is
As shown in FIG. 9, the thickness of the convex portion 13 in the circumferential direction is approximately equal to the thickness of the other portion of the container bottom 4.

Positioning for printing and labeling is the 10th step.
As shown in the figure, this is accomplished by engaging the positioning pawl 6 with the center-symmetrically located side portions 13e of each of the opposing convex portions 13 and rotating in the direction of the arrow shown by the solid line. If it is necessary to perform positioning by rotating in the direction of the arrow shown by the dotted line due to the structure of the printing press, etc., the positioning claw can be engaged with the opposite side 13e' and rotated. good.

Note that the annular protrusion 11 does not necessarily have to be an annular protrusion, but may be a rectangular or elliptical annular protrusion, that is, a loop-shaped protrusion, depending on the shape of the container.

(Effects of the invention) The stretch-blown polyethylene terephthalate container of the invention has a pair of convex portions located at center-symmetrical positions on the bottom thereof, so that it can be rotated by a positioning device (or It has the advantage that it can also be applied to printers (printing machines, etc.).

In addition, since the convex part is formed at the same time as stretch blow molding using a mold with a bottom mold having a correspondingly shaped concave part (with an air vent), there is no uneven thickness, and the circumferential direction of the convex part is Since the wall thickness is approximately the same as that of the other parts of the bottom part, it has the advantage of saving material costs. Furthermore, it has the advantage that engraving of the bottom mold is easy and the manufacturing cost of the bottom mold is low.

Further, since the convex portion is located within the ground plane of the annular protrusion, the container itself has the advantage of having stability in upright position.

Furthermore, since the sides of the convex part extend in a straight line,
This has the advantage that engagement with the positioning pawl is ensured.

[Brief explanation of the drawing]

Fig. 1 is a front view of a container which is an embodiment of the present invention, Fig. 2 is an explanatory diagram of the method of positioning the container, and Fig. 3 is a front view of a container which is an embodiment of the present invention.
The figure is a bottom view of a conventional container, and Figure 4 is the same as Figure 3.
FIG. 5 is a longitudinal sectional view taken along the line - in FIG.
Figure 8 is a bottom view of a container that is an embodiment of the present invention.
The figure is a longitudinal sectional view taken along the - line in Fig. 7, Fig. 9 is a longitudinal sectional view taken along the - line in Fig. 7, and Fig. 10 shows a state in which the positioning claw is engaged with the container of the present invention. It is a bottom view for explanation. 3...Stretch-blown polyethylene terephthalate container, 4...Bottom, 4a...Inner side of bottom annular protrusion, 6...Positioning claw, 11...Annular protrusion,
12... ground plane, 13... convex part, 13c... bottom surface of convex part.

Claims (1)

[Scope of utility model registration request] In a stretch-blown polyethylene terephthalate container having a bottom portion provided with an annular protrusion forming a ground surface on the periphery, a linearly extending side for engaging a positioning claw with an inner side of the annular protrusion of the bottom portion. A pair of convex portions having a portion are provided in center-symmetrical positions, and the wall thickness of the convex portion is approximately equal to the wall thickness of the other portion of the bottom portion in the circumferential direction of the convex portion;
A stretch-blown polyethylene terephthalate container characterized in that the bottom surface of the convex portion is located on or inside the ground plane.