JP2004155434A - Container gripper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a container gripper which can stably hold a neck ring of a container having the neck ring even with strong force against swinging due to centrifugal force or the like and during high speed operation, and can stably carry the container without causing a crack or an impression on the container. <P>SOLUTION: The gripper consists of a pair of forks having a holding part for holding the neck ring 31 of the container. The holding part 3 is constituted of a neck ring lower surface supporting flange 5 formed to be an arcuate recess having a flat upper face 4 for supporting the lower surface of the neck ring 31 of the container and a neck ring radially holding part 7 having a rising face 6 rising from the outer periphery of the flat upper face to hold the outer periphery of the neck ring. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a container gripper device, and particularly to a container gripper device suitable for gripping and transporting a plastic bottle having a neck ring filled with a content liquid.
[0002]
[Prior art]
Conventionally, when a plastic bottle having a neck ring filled with a content liquid, such as a PET bottle, is neck-conveyed, a pair of forks 21a and 21b of a gripper device 20 as shown in FIG. The neck 34 is conveyed while being held in the radial direction. However, it is extremely difficult to accurately regulate the shape of the lower neck portion 34 below the neck ring of the bottle into a cylinder in the bottle forming process, and as shown in FIG. There are variously deformed shapes, such as those having a middle-diameter shape and a narrow central portion as shown in FIG. 7B. For this reason, it is difficult to maintain stable gripping by the gripper device, and the gripping position is shifted during transport, resulting in a competition for bottles, resulting in a step difference with grippers and guides in a later process, which may hinder transfer. In addition, when gripping the lower or upper neck of the neck ring, the span s gripped by the grip of the fork is relatively short as shown in FIG. Have.
[0003]
In particular, the weight of the container after filling with the content liquid increases, and the influence of the centrifugal force cannot be ignored in the neck transfer system that transfers the container along an arc trajectory. Therefore, when gripping the lower or upper neck portion of the neck ring, the gripping force is unstable, so that the container may be swung outward by centrifugal force, and as shown in FIG. At this time, the lower part 22 of the fork tip hits the lower part 34 of the container neck, which causes indentations and flaws there.
[0004]
In addition, in order to stably perform container processing such as capping, a concave portion in which an outer peripheral portion of the neck ring is fitted is provided at a contact portion of the gripper with the neck ring, and an inner surface of the concave portion is formed in a tapered shape. There has been proposed a configuration in which a container is sandwiched by pressing a tapered surface against an outer peripheral portion of a neck ring to thereby prevent rotation of the container (see Patent Documents 1 and 2). However, in these cases, the concave portion of the gripper has a groove shape having a tapered surface, and the gripper is gripped by line contact or very small surface contact with the upper and lower surfaces of the neck ring, so the heights of the left and right grippers are slightly different. However, the bottle tends to tilt during transport, but it is difficult to finely adjust the height of the left and right grippers. In addition, because of the groove shape, high accuracy is required for the bottle conveyance height when the bottle is transferred to the gripper.
[0005]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2000-79988 [Patent Document 2]
JP 2001-287790 A
[Problems to be solved by the invention]
Therefore, the present invention is intended to solve the above-mentioned problems of the conventional container gripper device, and does not directly grip the neck of the container having the neck ring, and is capable of withstanding a shake against centrifugal force or the like of the container. It is an object of the present invention to provide a container gripper device capable of holding a container stably even at high speed operation and stably transporting the container without giving a flaw or an impression.
[0007]
[Means for Solving the Problems]
The container gripper device of the present invention for solving the above-mentioned problems is a gripper device comprising a pair of forks having a grip portion for gripping a neck ring of a container, wherein the grip portion has an arc-shaped concave portion or a concave portion formed by a combination of an arc and a straight line. A neck ring lower surface supporting jaw having a flat upper surface for supporting the lower surface of the container neck ring, and a rising surface rising from the outer peripheral edge of the flat upper surface to grip the outer peripheral edge of the container neck ring. And a neck ring radial holding portion having the following.
[0008]
The rising surface of the neck ring radial gripping portion is desirably formed so as to be inclined and risen toward the container to be gripped, but may also be formed to rise vertically from the upper surface of the neck ring lower surface supporting jaw. It is possible. The neck ring lower surface supporting jaw is formed so that the inner peripheral edge and the lower surface thereof are not in contact with the bottle to be gripped, so that even if shaking occurs, the tip of the fork hits the container neck and holds the container. No flaws or dents are left. In addition, the lower surface of the neck ring of the bottle is in close contact with the neck ring lower surface supporting jaw due to the weight of the bottle, so that the bottle can be transported in a stable posture. The container gripper device of the present invention is particularly effective in transporting and handling a container filled with contents and a sealed container equipped with a cap, but is not limited to these containers filled with contents. Needless to say, the present invention is also effective for conveying and handling an empty container having a neck ring and a preform before molding the container.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the embodiment shown in FIG.
The gripper device 1 of the present embodiment is a container gripper device for transporting and handling a synthetic resin bottle with a neck ring such as a PET bottle in, for example, a filling and sealing line, and has the highest strength at the site of the synthetic resin container and has a stable shape. By gripping the neck ring, the contents are filled so that even heavy containers can be stably gripped and transported reliably. A pair of bottles for gripping the neck ring 31 of the bottle 30 is provided. It has forks 2a and 2b. Each of the forks 2a and 2b has, at its tip, a gripping portion 3 formed of a semicircular concave portion that engages with the lower surface 32 and the outer peripheral edge 33 of the neck ring 31 of the bottle 30. The grip portion 3 forms a neck ring lower surface supporting jaw 5 having a flat upper surface 4 for supporting a lower surface 32 of the neck ring 31 and an arc surface having substantially the same curvature as the outer peripheral edge of the neck ring of the container from the flat upper surface 4. And a neck ring radial gripping portion 7 having a rising surface 6 that rises vertically or inclining toward the container side. The inclination angle of the rising surface 6 is, as shown in FIG. 1 and FIG. 2, when the container in which the cap is not yet mounted is used, the inclination angle α is in the range of 0 to 45 ° with respect to the vertical surface, and desirably. When handling a container with a cap having a good inclination of 5 to 30 °, if the inclination angle α is large, there is a risk of interfering with the cap. A tilt of 5 to 15 ° is good. The inner peripheral edge 8 and the lower surface 9 of the neck ring lower surface supporting jaw 5 are formed in such a dimensional relationship that they do not come into contact with the bottle while holding the bottle. That is, the radial width of the flat upper surface 4 is formed to be smaller than the width of the neck ring 31 of the container to be conveyed, and a gap is formed between the inner peripheral edge and the outer peripheral surface of the bottle neck portion in a gripped state. It is.
[0010]
The container gripper device of the present embodiment is configured as described above, and includes a plurality of forks having different curvature radii of the corresponding neck ring support jaws and rising surfaces formed according to the neck ring diameter of the container to be transported. By changing only the fork when changing the mold, it can be easily applied to the conveyance of containers of various sizes. That is, in the container gripper device of the present embodiment, the state in which the neck ring 31 of the bottle is gripped by the pair of forks 2a and 2b is, as clearly shown in FIG. 4 supports the lower surface of the neck ring 31, and the rising surface 6 of the neck ring radial grip 7 radially sandwiches the outer peripheral surface of the neck ring of the container. Since the neck ring is formed at the time of preform molding, its shape is stable and its lower surface maintains a flat surface, and its outer peripheral edge maintains a circular shape, so that the flat upper surface 4 and the rising surface 6 of the forks 2a and 2b are formed. It has a large effect of closely contacting and resisting shaking due to centrifugal force and can be stably gripped. In addition, since the rising surface 6 is inclined, a pressing force acts on the flange 4 from the rising surface 6, so that the lower surface of the neck ring increases the adhesion to the flat upper surface of the jaw, thereby stabilizing the posture of the container. As a result, the effect of suppressing vibration can be further improved.
[0011]
Therefore, according to the gripper device of the present embodiment, there is no phenomenon that the bottle gripping position is shifted due to shape instability as in the case of gripping the conventional neck portion and the bottles compete, and stable delivery and transport of the bottle can be performed. it can. Furthermore, since the outer peripheral edge of the bottle neck ring is gripped, the gripping span is wider than in the case of directly gripping the bottle neck portion in the related art, so that the force against the swing caused by the centrifugal force is large and the posture is stable. Effects. Moreover, since the grip is not in contact with the neck of the container, there is no flaw or indentation on the neck.
[0012]
Although the preferred embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various design changes are possible. For example, in the above-described embodiment, the rising surface is inclined toward the container. However, it is also possible to form the rising surface 16 so as to rise vertically, for example, as in the container gripper device 15 of the embodiment shown in FIG. In this case, no downward force acts on the neck ring, but since the lower surface of the neck ring 31 of the container is a flat surface, the neck ring is still supported by the flat upper surface 18 of the neck ring lower surface support jaw 17. In this state, the container is gripped in the radial direction on the rising surface, so that the container can be gripped in a stable posture.
[0013]
FIG. 3 is a plan view according to still another embodiment of the present invention. In the bottle gripper device 12 of the present embodiment, the gripping portion is formed by a combination of an arc and a straight line, and a triangular concave portion is formed as a whole. It is configured to be supported at the points and to grip the outer peripheral edge of the neck ring at four points, so that it can be stably gripped. In the present embodiment, the same components as those in the above embodiment are denoted by the same reference numerals, and the detailed description is omitted. The rising surface 6 in the present embodiment is formed to be inclined toward the container, but may be formed to rise vertically.
[0014]
【Example】
Example 1
A bottle shown in FIGS. 4 and 5 is a gripper device for discharging a capped PET bottle from a capper to a discharge conveyor in which the content is filled into a 500-ml PET bottle having a diameter of 28 mm and an outer diameter of a neck ring of 33 mm. The gripper device 10 was manufactured and applied to a PET bottle transfer test device. The basic configuration of the bottle gripper device of the present embodiment is the same as that of the embodiment shown in FIG. 1 and is shown using the same reference numerals, and detailed description of the configuration is omitted. The bottle gripper device 10 of this embodiment was manufactured so that the inclination angle of the rising surface 6 was 10 °, the arc radius of the base was 16 mm, and the width of the flat upper surface 4 of the neck ring radial gripping portion was 3 mm in the radial direction.
[0015]
The gripper device of the above embodiment was applied to the transport test device for 600 PET bottles / minute for transporting 200 PET bottles. However, transport failure due to shaking during transport by the gripper device, and No accidents such as poor delivery to the discharge conveyor were observed, and the product was successfully transported. Further, the state of the flaws and indentations on the neck of the transported PET bottle was examined, but almost no flaws and indentations were observed, and no defective products were found.
[0016]
【The invention's effect】
As described above, according to the container gripper device of the present invention, since the neck ring having a stable shape is gripped, it is possible to prevent the containers from advancing and to stably transport the containers. In addition, since the grip span is wider than that of the conventional device that grips the neck, the force against the swing caused by the centrifugal force is large, and the posture is stabilized. In addition, by inclining the rising surface, a downward force acts on the container, the lower surface of the neck ring is in close contact with the flat upper surface of the neck ring support jaw, and the posture of the container is more stable, and the effect of resisting shaking is more effective. growing. Since the gripper device is not in contact with the neck of the container, it is possible to prevent the container from being scratched or indented. And since the effect against the shaking is greater, shaking due to centrifugal force can be prevented, and the lower surface of the gripper tip does not hit the lower part of the neck of the container due to the shaking. .
[Brief description of the drawings]
FIG. 1A is a schematic plan view of a container gripper device according to an embodiment of the present invention in a state where a container is gripped, and FIG. 1B is a cross-sectional view taken along line AA.
FIG. 2 is a sectional view of a main part of a container gripper device according to another embodiment of the present invention.
FIG. 3 is a schematic plan view of a container gripper device according to another embodiment of the present invention in a state where a container is gripped.
FIG. 4 is a perspective view of the container gripper device according to the embodiment of the present invention in a state where the container is gripped.
FIG. 5 is a cross-sectional view showing a cross section of a gripping portion of a fork on one side in a state where the container is gripped.
FIG. 6A is a schematic plan view of a conventional container gripper device in a state where a container is gripped, and FIG. 6B is a cross-sectional view taken along line BB.
FIGS. 7 (a) and 7 (b) are enlarged views of a main part showing a deformed state of a neck portion of a synthetic resin container with a neck ring, and FIG. 7 (c) shows such a container gripped by a conventional gripper device. It is a front view showing the state where the container was shaken.
[Explanation of symbols]
1, 10, 12, 15, 20 Container gripper device 2a, 2b, 21a, 22b Fork 3 Gripping portion 4, 18 Flat upper surface 5, 17 Neck ring lower surface supporting jaw 6 Rising surface 7 Neck ring radial gripping portion 8 Inner peripheral edge 31 neck ring

Claims (4)

In a gripper device comprising a pair of forks having a grip portion for gripping a neck ring of a container, the grip portion is formed in an arc-shaped concave portion or a concave portion formed by a combination of an arc and a straight line, and supports a lower surface of the container neck ring. A neck ring lower surface support jaw having an upper surface, and a neck ring radial grip portion having a rising surface rising from the outer peripheral edge of the flat upper surface so as to grip the outer peripheral edge of the neck ring of the container. A container gripper device. The container gripper device according to claim 1, wherein a rising surface of the neck ring radial grip portion rises inclining toward a container to be gripped. The container gripper device according to claim 1, wherein a rising surface of the neck ring radial gripping portion rises vertically from an upper surface of the jaw. 3. The container gripper device according to claim 1, wherein the neck ring lower surface supporting jaw is formed so as not to be in contact with a bottle gripped by an inner peripheral edge and a lower surface thereof. 4.

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