JPH09267466A - Can printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of defective printing by transmitting securely the rotation of a bracket cylinder to mandrels and rotating the mandrels in a good manner. SOLUTION: This printer is provided with a rotatable bracket cylinder 2 with a bracket 11 to which ink is transferred from a plate provided on the outer periphery and a mandrel turret disposed in a manner of being brought into contact with the outer periphery of the bracket cylinder 2 and provided with a number of rototatable mandrels 4 in its circumferential direciton, and printing is carried out on the outer periphery of can bodies 10 by bringing the can bodies 10 fitted on the mandrels 4 into contact with the bracket 11. A belt 15 transmitting the rotation of the bracket cylinder 2 to the mandrels 4 by being brought into contact with the outer periphery of the mandrels 4 is wound on the outer periphery of the bracket cylinder 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a can printing apparatus for printing on the outer peripheral surface of a can body such as an aluminum can or a steel can.

[0002]

As is well known, so-called two-piece cans are
It is composed of a can lid and a can body. The can body is subjected to DI (deep drawing, ironing) processing and washing, and then the outer peripheral surface thereof is printed. For this printing, a device as shown in FIG. 7 has been conventionally used.

The printing apparatus shown in this figure is a multicolor printing apparatus for a can and comprises an ink adhering mechanism A and a can moving mechanism B. The ink adhering mechanism A includes a plurality of inker units 1 that supply ink, and a blanket cylinder 2 that contacts the inker units 1 to copy the ink and then contacts the can body 10 to print the ink on the can body 10. It consists of and. The blanket cylinder 2 has a blanket (not shown) on the outer periphery to which ink is transferred from the plate of the plate cylinder 3.

On the other hand, the can moving mechanism B includes the blanket cylinder 2
The mandrel turret 5 is arranged so as to contact the outer circumference of the mandrel and has a large number of mandrels 4 capable of rotating at intervals in the circumferential direction of the mandrel. The mandrel turret 5 is rotated (revolved) as shown by an arrow A in the figure to sequentially send the loaded can bodies 10 to a position in contact with the blanket cylinder 2 and discharge the printed can bodies 10. .

In this printing apparatus, each inker unit 1
An image composed of multicolored ink is formed on the plate of the plate cylinder by the above, and the image is transferred onto a blanket on the outer periphery of the blanket cylinder 2. Then, this image is printed on the can body by rotating contact between the blanket and the can body 10 fitted onto the mandrel 4.

[0006]

In a conventional printing apparatus,
The mandrel was rotated by the contact between the pre-spin portion on the blanket (the portion on the front side in the rotation direction of the portion on which the image is placed) and the can barrel, and the image of the blanket was transferred to the can barrel.

However, as the can diameter increases, the proportion of the image portion on the blanket increases, so
Since the length of the spin portion was shortened, the rotation of the blanket side could not be sufficiently transmitted to the side of the can body, and the rotation failure of the mandrel sometimes occurred. In addition, when the can diameter becomes large, the inertia of the mandrel and the can body becomes large, so that slippage occurs between the can body and the blanket, which may cause poor rotation of the mandrel. for that reason,
When the can diameter becomes large, there is a problem that printing defects are likely to occur.

In consideration of the above circumstances, the present invention can reliably transmit the rotation of the blanket cylinder to the mandrel,
An object of the present invention is to provide a can printing apparatus in which a mandrel is rotated well even when the can diameter is large to prevent printing defects.

[0009]

According to the invention of claim 1, a rotatable blanket cylinder having a blanket on the outer periphery to which ink is transferred from a plate, and a blanket cylinder arranged so as to contact the outer periphery of the blanket cylinder and own With a mandrel turret having a large number of mandrels capable of rotating in the circumferential direction,
In a can printing apparatus that prints on the outer circumference of a can by contacting a can fitted onto a mandrel with the blanket and rotating the can, a blanket cylinder is attached to the mandrel by contacting the outer circumference of the blanket cylinder with the outer circumference of the mandrel. It is characterized by winding a belt that conveys the rotation of.

According to a second aspect of the present invention, a belt winding groove is provided in the blanket cylinder, a belt having a round cross section is provided on an inner peripheral side of the belt winding groove, and a belt having a square cross section which is in contact with a mandrel is provided on an outer peripheral side thereof. Is housed in two layers and the belt having a rectangular cross section is elastically supported by the belt having a round cross section.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a main part of a can printing apparatus according to an embodiment. In FIG. 1, reference numeral 2 denotes a blanket cylinder that rotates in the direction of arrow B, and a plurality of blankets 11 are attached to the outer periphery of the blanket cylinder 2 at intervals. Each blanket 11
Is attached to the blanket cylinder 2 by being sandwiched between the fixed plate 12 and the pressing plate 13. The outer surface of the blanket 11 has a portion 11A on which an image is placed.
And a pre-spin portion 11B on the front side in the rotation direction thereof, and the pre-spin portion 11B is brought into contact with the outer periphery of the can body 10 fitted onto the mandrel 4, whereby the mandrel 4
In addition, the rotation of the blanket 11 is transmitted. The mandrel 4 is supported by the mandrel turret 5, as shown in FIG.

Also, the pre-spin portion 11B and the can body 10
Since there is a possibility that the rotation is not sufficiently transmitted due to the contact, the rubber belt 15 having a high friction coefficient is wound around the entire circumference of the holding plate 13 mounted on the blanket cylinder 2. . As shown in FIGS. 2 and 3, the belt 15 is accommodated in a belt winding groove 14 formed on the outer periphery of the pressing plate 13, and the outer peripheral portion of the belt 15 exposed from the belt winding groove 14 is a mandrel. It is designed to come into contact with the outer circumference of No. 4. Incidentally, the belt 1 of this embodiment
5 is a belt having a round cross section.

In the can printing apparatus of this embodiment, since the belt 15 contacting the outer circumference of the mandrel 4 is wound around the outer circumference of the blanket cylinder 2, the rotation of the blanket cylinder 2 is sufficiently applied to the mandrel 4 by the belt 15. It is transmitted and the mandrel 4 rotates stably. Especially the pre-spin part 1
Also in the area H between the blankets 11 on the front side of 1B, the belt 15 and the mandrel 4 may come into contact with each other, and the mandrel 10 can be surely passed even while the can body 10 passes through the portion 11A on which an image is placed. 4 and belt 1
Since 5 is in contact, the mandrel 4 rotates stably. Therefore, the can body 10 can be rotated well regardless of the can diameter, and printing defects can be prevented.

4 to 6 show the essential parts of another embodiment of the present invention. This embodiment is an example effective when the length of the blanket 11 (the length in the circumferential direction of the blanket cylinder 2) is long and it is more difficult to apply pre-spin to the mandrel 4 at the pre-spin portion 11B.

In the apparatus of this embodiment, the blanket cylinder 2
A belt winding groove 24, which is deeper than that in the above-described embodiment, is formed on the outer periphery of the pressing plate 23 that holds the blanket 11 on the outer periphery of the belt. Then, the belt 2 on the outer peripheral side having a square cross section is superposed on the belt winding groove 24 in two stages.
5 and an inner peripheral belt 26 having a round cross section are accommodated, and these belts 25, 26 surround the outer periphery of the blanket cylinder 2. The rectangular belt 25 on the outer peripheral side is made of a hard material such as urethane and has a trapezoidal cross section, the flat surface of the outer periphery thereof contacts the mandrel 4, and the inclined surface of the side portion is the tapered surface of the belt winding groove 24. It comes to abut. Also,
The round belt 26 is formed of a material such as NBR having high elasticity, and is formed in the inner portion of the belt winding groove 24 at the inner side of the square belt 2.
5 is elastically supported.

Thus, the lack of elasticity of the rectangular belt 25 is compensated for, and the contact surface of the mandrel 4 is enlarged to increase the frictional force and reduce the wear. Therefore, the rotation failure of the mandrel 4 can be prevented while ensuring the durability.

In both of the embodiments, the belt winding grooves 14 and 2 are
Since the pressing plate 4 is formed on the pressing plates 13 and 23, there is also an effect that it is possible to easily cope with the exchange of the belt.

[0018]

As described above, according to the invention of claim 1, the belt is wound around the outer circumference of the blanket cylinder, and the rotation of the blanket cylinder is transmitted to the mandrel by contacting the belt with the outer circumference of the mandrel. I did so,
The mandrel can be stably rotated regardless of the can diameter or the length of the pre-spin portion on the blanket. Therefore, the rotation of the can body is made favorable, and the occurrence of printing defects can be prevented. Claim 2
As in the invention of claim 2, the belt is a square belt or a round belt.
When stacking the layers, while ensuring the durability of the belt,
The stability of mandrel rotation can be increased.

[Brief description of drawings]

FIG. 1 is a perspective view showing a main part of an embodiment of the present invention.

FIG. 2 is a perspective view of a holding plate used in the embodiment.

FIG. 3 is a cross-sectional view of a belt winding portion in the embodiment.

FIG. 4 is a perspective view showing a main part of another embodiment of the present invention.

FIG. 5 is a perspective view of a holding plate used in the embodiment.

FIG. 6 is a sectional view of a belt winding portion in the embodiment.

FIG. 7 is a schematic side view showing the overall configuration of a conventional can printing device.

[Explanation of symbols]

 2 Blanket body 4 Mandrel 5 Mandrel turret 10 Can body 11 Blanket 14, 24 Belt winding groove 15 Belt 25 Belt with square cross section 26 Belt with round cross section

Claims (2)

[Claims] 1. A rotatable blanket cylinder having an outer periphery of a blanket to which ink is transferred from a plate, and a plurality of mandrels which are arranged so as to be in contact with the outer periphery of the blanket cylinder and can rotate in the circumferential direction of the blanket cylinder. With a mandrel turret that has, in the blanket, in a can printing device that performs printing on the outer circumference of the can by contacting the can fitted on the mandrel to rotate, on the outer circumference of the blanket cylinder, on the outer circumference of the mandrel. A can printing device characterized in that a belt for transmitting the rotation of the blanket cylinder is wound around the mandrel when brought into contact with the mandrel. 2. A belt winding groove is provided on the blanket cylinder, a belt having a round cross section is provided on an inner peripheral side of the belt winding groove, and a belt having a square cross section contacting a mandrel is provided on an outer peripheral side thereof in two stages. 2. The can printing apparatus according to claim 1, wherein the can printing apparatus is housed and the belt having a rectangular cross section is elastically supported by the belt having a round cross section.