JPH0126778B2 - - Google Patents

Description

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

Conventional technology With the diversification of containers, metal lids such as aluminum are wrapped around can bodies made of flexible materials such as plastic materials such as polyethylene terephthalate, laminates of metal foil and plastic sheets, and thin aluminum materials. It is suggested that the can be Can bodies made of such flexible materials have low axial load strength, so the lifter pressure during seaming is much lower than that for metal cans (the lifter pressure is 60 to 180 kg for metal cans). (for flexible materials, the limit is 20 kg), but the body of the can tends to buckle and it is difficult to perform proper seaming with conventional wrapping equipment. Ta. In particular, even a slight misalignment of the center ring on the lifter plate, which is not a problem when seaming metal cans, can cause the axial strength of the above-mentioned can bodies to drop significantly and cause buckling. is occurring.

Conventional lifter plate 20 in a seaming device for two-piece cans or three-piece cans filled with contents
has a smooth upper surface as shown in FIG. Conventionally, such a lifter plate 2
The can body is placed on the feed table at the center of the feed table so that it is rolled up in the turret recess. 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. In the case of conventional metal cans, even if the center was slightly off-center, the shaft strength was strong, so seaming could be done without any problem. However, in the case of a can body made of a flexible material with low axial strength as described above, if the can is held at a predetermined lifter pressure with the placement position on the lifter plate tilted away from the center, an uneven load will occur. The shaft strength is drastically reduced and the can body buckles. 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 and becomes tilted by 4 to 5 degrees. Sometimes it could withstand only 5-6 kg of lifter pressure.

Problems to be Solved by the Invention As mentioned above, conventional lifter plates are smooth, so if a can is placed incorrectly in the center of the lifter plate, the lifter will rise and a chuck will form on the can lid. When a can is clamped between the chuck and lifter plate after fitting, the can is clamped in an inclined state, resulting in an uneven load, which causes the can body made of a flexible material to buckle, making it difficult to roll the can properly. It was not possible to carry out the closing.

The present invention has been devised in view of the above-mentioned circumstances, and even if the can is not correctly positioned at the center of the lifter plate, the lifter plate moves upwards to clamp the can between the chucks. It is an object of the present invention to provide a lifter that can correct the misalignment between the center ring and tighten the seam with the center ring completed.

Means for Solving the Problems Means for solving the above problems will be explained based on FIGS. 1 and 2, which correspond to embodiments.

The present invention includes an outer circumferential plate 4 fixed on a substrate 2 and having a hole 5 of approximately the same diameter as the can body to be seamed in the center thereof, and a lower portion with an upper portion fitted into the hole 5 of the outer circumferential plate 4. The center plate 3 is supported on the base plate 2 so as to be movable up and down by a spring 7 with a weak pressing force. This problem has been solved by providing the lifter with a plate structure 1 designed to guide the can into the center.

Function A can with a can lid placed on top is plate structure 1.
The lifter rises while placed on the center plate 3 of the chuck B, and as the can lid is fitted onto the chuck B and pressure is applied to the can, the can is supported by a spring pressure that is weaker than the axial strength of the can body. The center plate is sinking. Thereby, the can c on the center plate
is guided by the inner circumferential wall of the hole 5 and sinks together with the center plate, so even if the mounting position is slightly deviated, it can be corrected and seaming can be performed with the center ring completed.

Embodiment Hereinafter, an embodiment of the apparatus of the present invention will be described with reference to FIGS. 1 and 2.

In the figure, reference numeral 1 denotes a lifter plate structure, and the lifter plate structure is constructed by providing a center plate 3 and an outer peripheral plate 4 on a substrate 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 base plate 2 by a spring 7 whose spring force is weaker than the axial strength of the can c, and its upper surface 6 is usually flush with the upper surface 8 of the outer peripheral plate 4 or It is located at a slightly lower position.

The lifter plate structure 1 constructed as described above is fixed by appropriate means on a plate support 10 in a conventional lifter as shown.

The plate support base 10 is supported on a rotating body 14 by a lifter spring 13 via a lifter spring adjustment screw 11 and a spring receiver 12. The rotating body 14 is rotatably supported by the lifter body 15, moves up and down integrally with the lifter body 15, and rotates on its own axis as the lifter revolves. Reference numeral 16 denotes a cam that moves the lifter body up and down.

The lifter configured as described above operates as follows.

The can c is fed from the feed table 17 to the center of the lifter A, that is, onto the center plate 3 by a turret. Thereafter, the lifter body 15 rises to clamp the can C between the chuck B and the lifter plate structure 1. At that time, even if the can c is slightly misaligned with the center plate, the spring pressure of the spring 7 supporting the center plate is weaker than the axial strength of the can c, so as the can c is pressed, the center plate is sinks downward from can c
The bottom of the hole 5 engages with the hole 5 of the outer peripheral plate 4.
The can is clamped while being guided by the inner circumferential wall of the can.

Therefore, the can is accurately positioned in the center of the lifter, and the can is not tilted and subjected to an uneven load as in the conventional case, and a predetermined shaft strength can be maintained.

Effects In the present invention, since the lifter plate structure is configured as described above, a can can be clamped between the lifter and the chuck while the can is accurately positioned at the center of the lifter. Therefore, the can does not tilt and receive unbalanced loads as in the past.
A predetermined shaft strength can be maintained, and the can can be prevented from buckling due to lifter pressure.

Further, the plate structure of the present invention can be easily installed by simply replacing the plate of a conventional lifter.

INDUSTRIAL APPLICABILITY As described above, the present invention is particularly effective when applied to a lifter of a winding device for a can body having a weak shaft strength.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a lifter according to an embodiment of the present invention, Fig. 2 is a sectional view of the main part of the lifter in a state where a can is clamped between the lifter and the chuck, and Fig. 3 is a sectional view of the main part of a conventional lifter. FIG. 1: Lifter plate structure, 2: Substrate, 3:
Center plate, 4: Outer plate, 5: Hole,
7: Spring.

Claims (1)

[Claims] 1. An outer circumferential plate fixed on a substrate and having a hole approximately the same diameter as the can body to be seamed in the center, an upper part fitted into the hole of the outer circumferential plate and a lower part pressed onto the substrate. A lifter for a can seaming device characterized by having a plate structure consisting of a center plate supported vertically by a weak spring.