JP2002068106A - Container clamping device for boxing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a container clamping device for a boxing machine capable of improving operational efficiency by expanding a positional range of a container capable of centering. SOLUTION: The device is equipped with a hanger pipe which is head- shakably suspended and of which the top part communicates to a compressed-air source, a gripper cup 40 of a downward cup shape mounted on the lower end of the hanger pipe, an airtight rubber cup 42, which is installed with a distance, inside of the gripper cup 40, and a container guide 60 which is screwed in a lower exterior part of the gripper cup 40 and formed such that a lower interior part has a form of a conical surface. In the container clamping device, a mouth part of a container 15 is clamped or separated by expanding or restoring the rubber cup 42 by supplying or discharging compressed air. The exterior of the container guide 60 is formed by a regular quadratic column surface of which the side length is smaller than a drum diameter of the container 15. A conical surface of which the bottom surface is a circle with a diameter shorter than a diagonal length of the regular quadratic column surface is formed on the same axis with that of the regular quadratic column surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container holding device for a container packing machine for packing a large number of containers filled with a liquid and sealed in a case.

[0002]

2. Description of the Related Art FIG. 8 is a plan view showing an example of a conventional container box packing machine using a robot. FIG. 9 is a side view of FIG. 8 as viewed in the direction of arrow A. In this box packing machine, six containers (bottles) filled with a beverage or the like are placed in a cardboard box (3 bottles).
(× 2 arrangement) are packed in boxes, each including a case conveyor 10 and a container conveyor 20 arranged in parallel, and an articulated robot 30 arranged on the side of the container conveyor 20.

The case conveyor 10 is provided for transporting an open case (box) 11, and the container conveyor 20 is provided for transporting a container (bin) 21. The articulated robot 30 has a robot head 31 provided at the tip of an arm, a grip head 32 suspended by the robot head 31 and capable of moving three-dimensionally without changing its posture, and attached to the grip head 32. A plurality of (three in the figure) grip units 33 and a container holding device 34 provided in each grip unit 33 for holding the mouth of one box of containers (3 × 2 rows of bottles) 21 at a time. Having.

[0004] The containers 21 are conveyed from an upstream process by a container conveyor 20, and are arranged in a plurality of rows (two rows in the figure) by a guide (not shown). When the leading container 21 is stopped at a predetermined position by a stopper (not shown),
The container 21 following the leading container 21 stops on the container conveyor 20 in a state in which the body portions of the containers 21 are in contact with each other.

Accordingly, the robot 30 moves the grip head 32 onto the group of containers 21 stopped on the container conveyor 20 to lower the same, and a plurality of container holding devices 34.
To grip the mouth of the container 21 for one box, raise the grip head 32, move the group of containers 21 held above to the case 11 on the case conveyor 10, and lower the grip head 32. , Container 21 group to case 11
Of the container 2 by the container holding device 34
The operation of lifting the grip head 32 by releasing the holding of the grip 1 and the operation of returning the grip head 32 to the standby position are sequentially executed.

FIG. 10 is a longitudinal sectional view showing the structure of the container holding device 34. 9, a stepped bracket 35 is inserted from below into a hole 33b provided in a plate 33a of the grip unit 33, and is fixed to the plate 33a by a nut 45. The bracket 35 is for attaching the hanger pipe 36, and has a tapered hole 35a and a plurality of square grooves 35b formed on the inner peripheral surface of the tapered hole 35a. As shown in FIG. 11, which shows a cross section of the bracket 35, in this example, four square grooves 35b are arranged at equal angular intervals.

The hanger pipe 36 is connected to the bracket 3
A tapered head 36a is fitted in the tapered hole 35a of the fifth bracket, and a plurality of keys 36b projecting from the peripheral surface thereof are fitted in the respective square grooves 35a of the bracket 35. Therefore, the hanger pipe 36 can move up and down but cannot rotate. The hanger pipe 36 has a vent at the center thereof, and a hose 39 for supplying compressed air is connected to the upper end of the vent.

The compression spring 46 urges the hanger pipe 36 downward. When the hanger pipe 36 is pushed up from below against the elastic force of the compression spring 46, the head 36a is lifted up to form a gap between the hanger pipe 36 and the bracket 35. ). A gripper body 38 is attached to a lower end of the hanger pipe 36 via a joint pipe 37. As shown in FIG. 12, the gripper body 38 includes:
Gripper cup 40, rubber cup 42 provided coaxially inside gripper cup 40, gripper cup 4
0 is formed of a container guide 41 and the like screwed to the outer peripheral surface of the lower edge.

The rubber cup 42 has an upper part screwed to a gripper cup 40 via a holder 43 with a screw 47, and a lower edge part formed by a packing ring 44 by the fastening force of the container guide 41.
The airtight pressure-contact is made to the lower end of the gripper cup 40 via. The container guide 41 is made of a resin having a small coefficient of friction, and its outer diameter d ₀ is set smaller than the body diameter of the container 21, and the diameter d ₁ of the lower end of its inner surface which is a conical surface is slightly smaller than the outer diameter d _0. It is set small. Accordingly, the container guide 41 has an annular bottom surface 41b based on the differential diameter d ₀ -d _1. The vertex angle α of the conical inner surface of the container guide 41 is empirically set to about 40 °.

As shown by a two-dot chain line in FIG. 12, when the cap of the container 21 is located at a position off the center of the gripper body 38 when the gripper body 38 is lowered, the conical inner surface of the container guide 41 has an arrow. The container 21 is moved toward the center of the gripper body 38 by applying a force in the direction B to the cap. Thus, the container guide 41 has a function as a centering means for aligning the axis of the container 21 with the center of the gripper body 38.

The container holding device 3 having the above-described configuration
Numerals 4 are arranged at the same interval as the trunk diameter of the container 21 in the conveying direction of the conveyor 20. Therefore, the container 21 on the container conveyor 20 is moved with the lowering of the grip head 32.
The group is inserted into the gripper body 38 of the container holding device 34 (see a two-dot chain line in FIG. 10).

At this time, compressed air is supplied from a hose 39 shown in FIG. This compressed air is hanger pipe 3
6, through the joint pipe 37 and the ventilation hole 40a of the gripper cup 40, and enter between the inner wall of the gripper cup 40 and the outer wall of the rubber cup 42;
Is bulged inward like a shape 42a indicated by a two-dot chain line to clamp the mouth portion of the container 21. When the compressed air is released, the rubber cup 42 returns to its original shape and the container 2
1 away from the mouth.

[0013]

In the above-mentioned boxing machine in which a plurality of containers 21 are handled as one group, a plurality of rows of containers 21 conveyed by the container conveyor 20 are separated by a container dividing device (not shown). Each column is divided. Then, after the containers 21 in each row are conveyed while being aligned by the partition guide, the first container 21 is forcibly stopped by the stopper member, and as a result, the subsequent containers 21
Are sequentially stopped while the body portions are in contact with each other.

[0014] Even thereafter, the container conveyor 20 continues to be driven, so that the stopped containers 21 are subjected to line pressure. If the container 21 is made of glass,
Although the container 21 is not deformed by the line pressure, when the container 21 is a PET container (particularly, a container filled with a non-gas beverage), the container 21 is deformed by the line pressure.

When the containers 21 are deformed, the distance between the containers 21 in the advancing direction is reduced, and the number of containers 21 arranged in the advancing direction (the number processed by the grip head 32 at one time) is increased. Then, with the accumulation of the deformation amounts of the individual containers 21, the position of the container 21 on the upstream side with respect to the leading container 21 is shifted by a distance L from the regular stop position as shown in FIG.
However, the position of the container 21 and the position of the corresponding container holding device 34 are shifted from the position of the container 21.

When the container holding device 34 is lowered in this state, the container 21 is not centered by the container guide 41, and the lower end surface of the container guide 41 comes into contact with the upper surface of the cap sealed by the container 21. . As a result,
The push-up safety device (not shown) operates, and the container box packing device stops. The conventional box packing device has a disadvantage that the stop operation as described above frequently occurs and the operation efficiency is reduced.

On the other hand, the conventional box packing device has the following problems. That is, when the container 21 is centered and clamped by the container clamping device 34, the conical surface of the shoulder of the container 21 may come into contact with the conical inner surface of the container guide 41. After the container 21 is clamped, the compressed air between the rubber cup 42 and the inner wall of the gripper cup 40 is released to release the clamping, but the space between the shoulder of the container 21 and the container guide 41 is closed. If the release of the air is performed in the above state, the space becomes a negative pressure when the rubber cup 42 tries to return to the original shape, so the restoration of the rubber cup 42 is delayed and the gripper cup 40 is moved to the container 21. May not be able to be separated sufficiently.

An object of the present invention is to solve the above-mentioned situation,
It is an object of the present invention to provide a container holding device for a boxing machine capable of improving the operating efficiency by enlarging a position range of a centerable container. Another object of the present invention is to provide a container holding device of a boxing machine that can smoothly remove a container.

[0019]

According to the present invention, there is provided a hanger pipe suspended in a swingable manner and having an upper end communicating with a compressed air source, and a downward cup-shaped gripper cup attached to a lower end of the hanger pipe. A rubber cup airtightly provided inside the gripper cup with a gap therebetween, and a container guide screwed below and outside the gripper cup and formed such that an inner lower portion forms a conical surface, and is compressed. In a container clamping device for expanding and restoring the rubber cup by supplying and discharging air to clamp and release a mouth of a container, a square prism having a side length outside the container guide is smaller than a body diameter of the container. A conical surface having a base circle whose diameter is smaller than the diagonal dimension of the square prism is formed coaxially with the square prism inside the container guide. In the embodiment of the present invention, the hyperbola, which is the inflection line between the square prism surface and the conical surface of the container guide, is replaced by two inverted V-shaped tangent lines that are in contact near both ends of the hyperbola. Further, in the embodiment of the present invention, a groove is formed in the inner conical surface of the container guide so as to open a space formed by the conical surface and the container in contact with the conical surface to the atmosphere. A plurality of the grooves may be provided along a generatrix of the inner conical surface.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a side view showing a box packing device provided with the container holding device of the present invention, FIG. 2 is a sectional view of a grip body of the container holding device, FIG. 3 is a bottom view of FIG.
FIG. 4 is a sectional view taken along line BB of FIG.

The container box packing apparatus 1 according to the present invention has a configuration similar to the conventional container box packing apparatus shown in FIGS. 8 and 9 except for the container holding device 4. That is, in FIG. 1, the grip head 2 is mounted on a robot head of an articulated robot (not shown). A plurality of (three in this embodiment) grip units 3 are fixed to the grip head 2, and a plurality of the container clamping devices 4 (3 × 6 in this example) are respectively mounted on the horizontal plates 16 of these grip units 3.
Pieces) are arranged. The container holding devices 4 are arranged along the transport direction of the container conveyor 18, and the arrangement interval is set to a dimension corresponding to the trunk diameter of the container 15.

The structure of the container holding device 4 is the same as the conventional container holding device 34 shown in FIG. 10 except for the container guide 60 of the gripper body 51 shown in FIG. Therefore, hereinafter, the basic shape of the container guide 60 shown in FIGS. 2 to 4 will be described. The outside of the container guide 60 (made of resin) is a cylindrical surface having an outer diameter “d2” slightly shorter than a diagonal line of a square having a dimension “L ₀ ” that is about 3 mm to 7 mm smaller than the outer diameter of the container 15. The inside has an apex angle α having a diameter “d3” slightly shorter than the outer diameter “d2” as a bottom surface (about 40 °).
Of the cylindrical surface and the conical surface 60e.
Is concentrically cut by a square quadrangular prism having a bottom surface of a square of dimension “L ₀ ” whose opposite side is about 3 mm to 7 mm smaller than the outer diameter of the container 15.

The outer lower edge of the container guide 60 thus formed is a circular arc 60a having four corners in the shape of a circular arc, and a hyperbola 60b appearing between the corners on the side surface of the square prism. In addition, the outer part of the upper part has a conical shape excluding the excess thickness. The difference between the diameters d2 and d3 is for chamfering the lower end. Of course, the container guide 60 can also be processed by processing a square bar.

The container holding device 4 is attached to the horizontal plate 16 of the grip unit 3 so that one of the square prism surfaces of the container guide 60 is parallel to the traveling direction of the container conveyor 18. The two-dot chain line 60c in FIG. 2 is obtained by replacing the hyperbola 60b appearing on the side surface of the regular square prism surface with two inverted V-shaped tangents that contact the lower side of the hyperbola. This can be formed by cutting the hyperbola 60b by two planes which intersect so that the intersection line becomes horizontal. In this case, the inflection line between the side surface of the square prism surface and the conical inner surface 60e is a space curve that is slightly bent inside the square prism surface as shown in FIG. Note that FIG.
As shown in FIG.
0 conical inner surface 60e has a narrow groove 60d along its generatrix.
Are formed. In addition, as shown in FIG. 5 which is a view taken in the direction of arrow C in FIG. 2, the narrow groove 60d is formed in a semicircular shape.

The operation of the container holding device 4 will be described below. The container (PET bottle) 15 shown in FIG. 1 is filled with a beverage in an upstream process and the cap 17 is sealed. The containers 15 are divided into a plurality of rows (three rows in this embodiment) in a process of being transported by the container conveyor 18 and then transported in a state of being aligned by a partition guide (not shown).

When the first container 15 comes into contact with the end stopper 19 and stops, the subsequent containers 15 are also moved to the container conveyor 18.
Stop sequentially up. The stopped group of containers 15 is deformed by receiving line pressure, so that the container interval dimension in the traveling direction is smaller than the arrangement interval dimension of the container holding device 4 in which the body diameter dimension of the container 15 is one pitch. Become. Note that the deformation dimension of the container 15 differs depending on the type of the container 15 and the type of the filling liquid, and the dimensions are not constant even under the same condition. Since the deformation dimension is about 3 to 7 mm for one container 15,
The cumulative deformation amount of the containers 15 in one row is about 50 mm at the maximum.

The grip head 2 is moved by a robot (not shown) onto the group of containers whose alignment has been stopped, and the center of the grip head 2 is positioned substantially at the center of the group of containers 15 (18 in this embodiment) in the processing direction. Adjust the position. As a result, the dimensional difference between the center of the container holding device 4 and the center of the container becomes “H” which is half the cumulative deformation amount, and the lowering of the grip head 2 causes the container holding device 4 to It becomes possible to pinch while centering the part.

Next, the holding operation of the container 15 on the downstream side, which has a large dimensional difference from the center of the container holding device 4, will be described with reference to FIGS.
This will be described with reference to FIG. 6 is a side sectional view showing a state where the container guide 60 is in contact with the cap 17 mounted on the container 15, and FIG. 7 is a sectional view taken along the line DD of FIG. As shown in FIGS. 6 and 7, when the container holding device 4 descends, the hyperbola 60 b on the side surface in the traveling direction of the container guide 60 contacts two points of the top surface angle 17 a of the cap 17 of the container 15 (F1 position).
I do. At this time, since the hyperbola 60b of the container guide 60 has an inclination angle with respect to the top surface angle 17a of the cap 17, it receives the pressing force due to the contact with the cap 17 due to the wedge effect, and moves to the right in the drawing. It will descend.

Therefore, the container holding device 4 has the relative position "F1", "F2",
Moves to "F3" and "F4" sequentially, and tilts (swings) at an angle to the mouth of container 15 (below cap 17).
Can be centered and pinched.

In FIG. 1, the container holding device 4 at the front and rear ends swings right and left. Therefore, if the shift in the X direction of the center of the container 15 with respect to the center of the container guide 60 in FIG.
Can be expected. That is, according to the container holding device 4 according to this embodiment, the allowable range of the deviation between the center positions of the container guide 60 and the container 15 where the centering action can be expected can be increased.

When the position of the container 15 is "S" in the Y direction from the X axis,
If the shift is "2", the allowable shift dimension "S1" is reduced, but since the actually generated shift "S2" in the Y direction is about 5 mm, the influence on the allowable shift dimension "S1" is not large. The container 1 in the hyperbola 60b
When the contact point of the cap 5 with the cap 17 rises upward, the tangent of the hyperbola 60b at the contact point approaches horizontal, so that the angle formed between the hyperbola 60b and the top surface angle of the cap becomes small, and the wedge effect is weakened. . However, in the case of the inverted V-shaped notch 60c shown by the dotted line in FIG. 2, there is an advantage that the inclination angle with the upper surface of the cap 17 does not become small even if the contact point goes up.

Next, the conical surface 60e of the container guide 60
Will be described. If the narrow groove 60d is not formed, when the shoulder portion of the container 15 contacts the conical surface 60e of the container guide 60 over the entire circumference, the conical inner surface 60e of the container 15 and the container guide 60 is formed.
The space between and becomes airtight. In this state, as described above, when the compressed air between the rubber cup 42 and the inner wall of the gripper cup 40 is released and the rubber cup 42 is caused to retreat, the space becomes negative pressure. Therefore, the gripper cup 40 cannot be sufficiently separated and removed from the container 15. However, according to the container holding device 4 of the above embodiment, the space between the container 15 and the conical inner surface 60 e of the container guide 60 is formed by the narrow groove 60.
d, the gripper cup 40
Can be easily separated from the container 15.

[0033]

According to the container holding device of the boxing machine according to the present invention, the following effects can be obtained. (1) The outside of the container guide is formed by a square prism surface having a side length whose dimension is smaller than the body diameter of the container, and a circle having a diameter shorter than the diagonal dimension of the square prism surface is formed inside the container guide. Since the conical surface serving as the bottom circle is formed coaxially with the square prism surface, the container guide does not exceed the diameter of the body of the container. Since the position range of the centerable container is expanded, resin containers such as PET containers for non-gas beverages, which are easily deformed by line pressure or the like, can be held under suitable conditions. (2) Since the space between the container and the conical inner surface of the container guide is opened to the atmosphere via the groove formed in the conical inner surface, the container guide can be easily separated from the container. (3) By the effects of (1) and (2), it is possible to reduce the time loss caused by the failure of the container holding operation in the box packing machine, and to improve the working efficiency.

[Brief description of the drawings]

FIG. 1 is a side view showing the configuration of a container box packing device to which a container holding device according to the present invention is applied.

FIG. 2 is a half sectional view of a gripper body.

FIG. 3 is a bottom view of the gripper body.

FIG. 4 is a sectional view taken along line BB of FIG. 3;

FIG. 5 is a view of a local area of the arrow C in FIG. 2;

FIG. 6 is an explanatory view showing a centering operation of the container guide.

FIG. 7 is a sectional view taken along line DD of FIG. 6;

FIG. 8 is a plan view showing an example of a conventional box packing machine.

FIG. 9 is a side view as viewed in the direction of arrow A in FIG. 8;

FIG. 10 is a sectional view showing a general structure of a container holding device.

FIG. 11 is a cross-sectional view of the bracket.

FIG. 12 is a half sectional view of a gripper body.

FIG. 13 is a side view showing a relative positional relationship between a container and a container guide.

FIG. 14 is a plan view showing a relative positional relationship between a container and a container guide.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 container box packing device 2 grip head 3 grip unit 4 container holding device 10 case conveyor 15 container (PET bin) 17 cap 18 container conveyor 36 hanger pipe 40 gripper cup 42 rubber cup 51 gripper body 60 container guide

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3E003 AA01 AB02 BB02 BB04 BC03 BD04 CA02 CA04 CB03 CB06 DA02 DA03 DA07 3F061 AA04 BA11 BE22 BE24 BF04 DB00 DB02

Claims (4)

[Claims] 1. A hanger pipe suspended at a swingable upper end and communicating with a source of compressed air, a downward cup-shaped gripper cup attached to a lower end of the hanger pipe, and a gap formed inside the gripper cup. And a container guide which is screwed to the outside and below the gripper cup and has an inner lower part formed as a conical surface, and the rubber cup is supplied and discharged by compressed air. A container holding device for holding and releasing the mouth of a container by expanding and restoring the container guide, wherein the outside of the container guide is formed by a square prism surface having a side length whose dimension is smaller than the body diameter of the container; A container holding device for a boxing machine, characterized in that a conical surface having a base circle whose diameter is shorter than the diagonal dimension of the square prism is formed coaxially with the square prism. 2. A hyperbolic line, which is an inset of a square prism surface and a conical surface of the container guide, is replaced by two inverted V-shaped tangent lines that are in contact near both ends of the hyperbola. Item 2. A container holding device for a boxing machine according to item 1. 3. The container guide according to claim 1, wherein a groove is formed in an inner conical surface of the container guide to open a space formed by the conical surface and the container in contact with the conical surface to the atmosphere. 3. The container holding device of the boxing machine according to 2. 4. The container holding device according to claim 3, wherein a plurality of the grooves are provided along a generatrix of the inner conical surface.