JPH0150496B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a can centering device for a can seaming device, and particularly to a can centering device for a seaming device suitable for seaming cans with weak shaft strength.

Conventional technology With the diversification of containers, cans made of plastic materials, laminated materials, DI cans, etc. are provided by seaming metal lids onto can bodies with weak shaft strength. The speed is increasing. Therefore, even a slight deviation of the center ring on the lifter plate, which did not have much effect on the seaming of conventional metal cans, can drastically reduce the axial strength of the can body and cause buckling. There is a problem that occurs.

A conventional lifter plate in a tightening device for a two-piece can or a three-piece can filled with contents has a smooth upper surface. Conventionally, cans are centered on the lifter plate by being rolled up in recesses in a can guide turret and a seaming turret. However, since the diameter of the turret recess is larger than the diameter of the can body and there is some play between the turret recess and the can body, the can may not be correctly positioned at the center of the lifter plate. Furthermore, even if the lifter was properly centered, centrifugal force was applied due to the high speed rotation of the lifter as it rose, causing the centering of the chuck to shift.
In the case of conventional metal cans, even in such cases, if there was a slight deviation, the centering could be corrected by the lifter pressure, and the cans could be chucked correctly and seaming could be carried out without any problems. However, in the case of a can body made of a flexible material with low axial strength as described above, if the can is clamped with a predetermined lifter pressure in a state where the center is off, an uneven load will occur, the axial strength will be drastically reduced, and the can body will be seated. It causes bending. According to the results of experiments conducted by the present inventor, the axial strength of the can decreases by 2 to 3 kg every time the can is tilted by 1 degree under a lifter pressure of 18 to 20 kg, and at a certain point it suddenly decreases to a point where it tilts by 4 to 5 degrees. Sometimes they could withstand only 5-6 kg of lifter pressure.

Problems to be Solved by the Invention As mentioned above, since the conventional lifter plate is smooth, it is difficult to correctly position the can in the center of the lifter plate, and the center position may shift. Furthermore, even if the centering was performed correctly, the high-speed rotation of the lifter during the lifter's upward movement caused the can to swing and become eccentric, causing the centering of the chuck to shift. As a result, a load acts on the can,
Can bodies made of flexible materials buckle and cannot be properly seamed.

The present invention was devised in view of the above-mentioned circumstances, and it is possible to easily and reliably center the ring on the lifter plate, and to prevent the center ring from becoming eccentric due to rotation even while the lifter is rising. It is an object of the present invention to provide a can centering device in a can seaming device that can be chucked in a perfect state.

Means for Solving the Problems Hereinafter, the configuration of the present invention will be explained based on drawings corresponding to embodiments.

The can centering device of the can seaming device of the present invention includes an outer peripheral plate 4 in which a hole 5 having approximately the same diameter as the can body c to be seamed is bored in the center, and a hole 5 that fits into the hole 5 of the outer peripheral plate 4. The center plate 3 is supported by a holding spring 7 on a plate support base 2 so as to be movable up and down. , a rod 22 that passes through the chuck 21 and moves up and down;
The holding spring 7 is characterized in that its spring force is set to be weak by the knockout spring 27. That is.

Operation When the can c with the can lid e placed on the top is placed on the center plate 3 of the plate structure 1, the knockout pad 23 is lowered and the lifter is also raised, and the knockout pad 23 is lowered. 23 presses the lid e. At this time, the spring force of the knockout spring 27 is greater than the spring force of the holding spring 7, so the center plate gradually sinks.
The bottom of the can c fits into the hole 5 of the outer peripheral plate 4, and the inner peripheral wall of the hole 5 guides and presses the can. Thereafter, the can is guided to the chuck 21 while the can C and the lid E are cushioned and clamped by the center plate 3 and the knockout pad. Therefore, the can c can be reliably centered on the lifter plate, and the can c can be reliably chucked without being shifted due to the centrifugal force caused by the rotation even during lifting.

Embodiments Hereinafter, embodiments of the apparatus of the present invention will be described in detail with reference to FIGS. 1 to 4.

The present invention is comprised of a lifter plate structure 1 and a knockout pad device 20.

The lifter plate structure 1 is constructed by providing a center plate 3 and an outer peripheral plate 4 on a plate support 2. A hole 5 having approximately the same diameter as the can c to be seamed is bored in the center of the outer peripheral plate 4, and the center plate 3 is fitted into the hole 5 so as to be able to move up and down. The center plate 3 has its lower surface supported on the support base 2 by a holding spring 7 whose spring force is weaker than the axial strength of the can c, and normally its upper surface 6 is the upper surface 8 of the outer peripheral plate 4. It is located on the same level as or slightly lowered.

The plate support base 2 is supported by a rotating body 12 via a lifter spring 11 as in the conventional device, and moves up and down integrally with the lifter body 13.
It also rotates as the lifter revolves. In addition, 1
4 is a lifter cam, and 15 is a drive gear.

On the other hand, the knockout pad device 20 has a knockout pad 23 fixed to the lower end of a rod 22 that passes through the chuck 21 and moves up and down. The upper part of the rod 22 is the knob outcome cam 2.
The cam follower 25 moves up and down following the cam 4, and is supported via a bearing 26. A knockout spring 27 is provided between the upper end of the rod 22 and the cam follower 25, as shown, so as to constantly press the rod 22 downward.

The spring force of each spring used in the above device is set so that the following relationship holds: lifter spring 11>>knockout spring 27>holding spring 7.

In addition, in the figure, 28 and 29 are can guides, and 30
is a feed finger, 31 is a can guide turret, 32 is a seaming turret, 33 and 34 are cover guides, 35 is a first seaming roll, and 36 is a second seaming roll, which are the same as the conventional one. .

The centering device configured as described above operates as follows.

The can c is pushed by the feed finger 30 and conveyed along the can guides 28 and 29, and is supplied onto the lifter plate structure 1 (the state shown in FIG. 1).
In this state, the upper surface 6 of the center plate 3 and the upper surface 8 of the outer peripheral plate 4 are substantially on the same plane. Next, the can guide turret 31 and the seaming turret 3
2, position the can c on the center of the center plate by rolling it up. At the same time, the can lid e is supplied onto the can c along the lid guides 33 and 34, and as the knockout pad 23 descends,
The lifter also rises, and the knockout pad 23 presses the lid e. At this time, since the spring force of the knockout spring 27 is greater than the spring force of the holding spring 7, the center plate gradually sinks, and the bottom of the can c engages with the hole 5 of the outer peripheral plate 4, causing the inner peripheral wall of the hole 5 to engage. Press the can while guiding it (as shown in Figure 2).

Furthermore, as the turret rotates, the knockout pad 23 is lowered by the knockout cam 24 and presses the lid e, but at the point when it reaches the center line between the can guide turret 31 and the seaming turret 32 (the In the state shown in Fig. 3), the center plate 3 has already sunk to the lowest position (L ₁ ), so the pressing force of the knockout pad presses the knockout spring 27 and compresses the spring 27 by L ₂ . . Therefore, the can c and the lid e are strongly pressed by both springs 7 and 27, and are properly centered, and the can is prevented from swinging due to centrifugal force due to rotation and revolution. .

Thereafter, as the lifter rises, the knockout pad 23 simultaneously rises while contacting and engaging with the can lid, guides the can to the chuck 21, and chucks the can lid e (Fig. 4). condition).
During this time, the lifter plate structure 1 and the knockout pad 23 are constantly rotating, but the bottom of the can c is fitted into the hole 5 of the outer peripheral plate 4, and the knockout pad 23 is not attached to the can lid e. contact and engage and guide the can to the chuck 21 with the can being clamped and pressed by the knockout pad 23 and the center plate 6 via the knockout spring 27 and the holding spring 7, so that it does not shake during rotation. Centering on the chuck 21 can be performed correctly without any problems.

When the can lid 1 comes into contact with the chuck 21, the can c and the lid e are clamped between the chuck 21 and the center plate 3 with a predetermined lifter pressure, and the first seaming roll 35
Sealing is performed by the second seaming roll 36.

Effects As described above, according to the present invention, by the joint action of the lifter plate structure and the knockout pad device, the can can be accurately positioned at the center of the lifter, and the knockout pad and the center Since the can is guided to the chuck while being held under pressure by the plates, centering is performed accurately. Therefore, since the can is not tilted and subjected to an uneven load as in the conventional case, a predetermined axial strength can be maintained and the can can be prevented from buckling due to lifter pressure.

[Brief explanation of drawings]

The drawings show an embodiment of the can centering device of the can tightening device according to the present invention in the order of steps. The process in which the outpad descends and pushes the lid and can downward, and the center plate descends. Figure 3 shows the process in which the knock out pad strongly pushes the can downward to prevent it from moving due to centrifugal force. Figure 4 shows the knock out process. FIG. 6 is a sectional view of each side in the process of fitting the lid to the seaming chuck using the pad and lifter. 1: Plate structure, 2: Plate support,
3: Center plate, 4: Outer plate, 5:
Hole, 7: Holding spring, 11: Lifter spring, 12: Rotating body, 13: Lifter body, 14: Lifter cam, 20: Knockout pad device, 21: Seaming chuck, 22:
Rod, 23: Knock out pad, 24: Knock out cam, 25: Cam follower, 26: Bearing,
27: Knockout spring, 31: Can guide turret, 32: Sealing turret, 33,3
4: Cover guide, 35: First seaming roll, 3
6: Second tightening roll.

Claims (1)

[Claims] 1. An outer circumferential plate having a hole approximately the same diameter as the can body to be seamed in the center thereof, which is fitted into the hole of the outer circumferential plate and supported on a plate support base so as to be movable up and down by a holding spring. A plate structure consisting of a center plate, a rod that is provided to the cam follower of the knockout cam via a knockout spring and moves up and down through the chuck, and a knockout pad fixed to the lower end of the rod. 1. A can centering device for a can seaming device, characterized in that the holding spring is set to have a weaker spring force than the knockout spring.