JPS6132765Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for overprinting the outer peripheral surface of a cylindrical can body.

Overprinting is a type of multicolor printing in which an upper layer of ink partially overlaps a lower layer of ink.

Conventional overlapping printing equipment for the outer peripheral surface of the cylindrical can body is
A plurality of transfer cylinders, the number of which is equal to the number of colors, are provided, and each of the transfer cylinders is sequentially arranged along the conveyance path of the can to be printed, which is fitted onto a mandrel disposed on a vertically rotating disk and conveyed. A predetermined amount of ink is applied to a predetermined portion of the outer peripheral surface of each transfer cylinder in a section equal to the outer circumferential length of the body of the can to be printed in the circumferential direction of the outer peripheral surface. The ink-applied portion of the outer circumferential surface of the first transfer cylinder is brought into rolling contact with the outer circumferential surface of the body of the can being conveyed,
One rotation of the can body transfers the first layer of ink, which is the lowest layer, onto the outer peripheral surface of the can body body, and then, after drying the transferred ink, the second layer is transferred by another transfer cylinder. This is a method in which the ink of each layer is transferred in the same manner as described above, dried, and then repeated in the same manner to perform overlapping printing.

Therefore, in the overprinting device of the above type, it is essential to have a plurality of transfer cylinders, so the can body receives an impact each time it starts contact with each transfer cylinder, and each time the can body receives a shock from the outer circumferential surface of the can body body. Slippage occurs between the transfer cylinder and the transfer cylinder. This is because the mandrel in the conventional device only has the function of latching the can body, so when the contact starts, the rotating transfer cylinder and the non-rotating can This is due to contact with the body and an impact caused by the speed difference between the two. For this reason,
There is a problem in that the position of the transfer start end of each transfer cylinder to the can body is not constant, resulting in deviations in the relative positions of each color, resulting in a decrease in print quality.

Recently, there is a printing method proposed in JP-A-56-72958, and when performing overprinting using this method, if there is only one transfer cylinder in contact with the can body, overprinting will occur. Since all of the ink of each layer is applied to the outer peripheral surface of one transfer cylinder sequentially and serially in the circumferential direction of the outer peripheral surface, the can body that starts contact with the transfer cylinder is coated with the ink of the uppermost layer. Since the can body rolls and rotates continuously until it is transferred, the can body only receives one impact when it starts contacting the transfer cylinder, and the transfer start position of each layer of ink to the can body is also constant. However, according to this method, the viscosity of the ink to be supplied is adjusted to be lower than that of the ink in the lowest layer, thereby eliminating the need for a drying step.

However, even in the above-mentioned Japanese Patent Application Laid-open No. 56-72958, the impact received at the start of contact is not desirable, and in order to perform highly accurate overprinting, it is necessary to convert the rolling contact between the can body and the transfer cylinder into frictional force. However, if two or more transfer cylinders are provided, the problem arises that the position of the transfer start end is not constant, similar to the conventional apparatus described above.

The present invention solves the problem of printing accuracy in the above-mentioned conventional devices and Japanese Patent Application Laid-open No. 56-72958, etc. by actively rotating the can body that rolls into contact with the transfer cylinder at a circumferential speed that is synchronized with the circumferential speed of the transfer cylinder. The present invention provides an overprinting device that eliminates the problem of overprinting, and for this purpose, a can body holding mechanism that presses and holds the can body from the inner surface of the mandrel, and the mandrel that moves on a vertically rotating disk via a support base. This device is equipped with a synchronized drive rotation mechanism that can drive and rotate the can at a constant speed at any position on the rotating disk. It also becomes possible to perform halftone dot printing, which creates a pattern using a collection of minute amounts of ink, which had not been done before.

That is, in the present invention, near the periphery of the vertically rotating disk,
A large number of mandrels are horizontally arranged at equal intervals through support stands that are movable in the diameter direction of the vertically rotating disk, and a cylindrical can body is fitted onto the mandrels. The can body is conveyed along a predetermined path by rotation of the vertically rotating disk and movement of the support base, and the outer circumferential surface of the body of the can body being conveyed rolls into contact with a transfer cylinder whose outer circumferential surface is coated with ink. Accordingly, in the apparatus for performing overprinting on the outer circumferential surface of a cylindrical can body, each of the mandrels has a mandrel shaft rotatably supported by each of the supports, and
A tapered portion formed on the outer peripheral surface of the mandrel shaft and a reverse taper that matches the tapered portion are formed on the inner peripheral surface, and the mandrel shaft is bound into an integral cylindrical body by a spring member so as to be able to expand and contract in diameter. A can body holding mechanism is provided with a plurality of holding members that are slidably fitted only in the axial direction of the mandrel shaft via guide members, respectively, to the tapered portion of the mandrel, and further, one end side is fixed to the mandrel shaft of each of the mandrels. The other end of the offset joint is fixed to the drive shaft of the vertical rotating disk that rotatably supports a shaft having a pinion fixed to the other end. a two-stage ring gear that is loosely supported on the drive shaft of the vertical rotating disc, one gear meshing with each of the pinions, and the other gear meshing with the drive-side pinion; This is an overlapping printing device for the outer circumferential surface of a cylindrical can body body, characterized in that it is equipped with a mandrel synchronized drive rotation mechanism.

Hereinafter, it will be explained in more detail with reference to Examples.

FIG. 1 is a schematic configuration diagram showing an embodiment of the overlapping printing device to which the present invention is applied, and FIG. 2 is an A-A diagram of FIG. 1.
A detailed cross-sectional view showing a specific example of a mandrel synchronized drive rotation mechanism corresponding to the arrow view, FIG. 3 is a partial detailed cross-sectional view of FIG. 2 showing a specific example of a misaligned joint, and FIG. FIG. 3 is a partially enlarged detailed sectional view of FIG. 2 showing a specific example;

In FIG. 1, reference numerals 1 and 1' are transfer cylinders, and two blankets 2 are disposed on the outer circumferential surface of each transfer cylinder, and each blanket has a length in the circumferential direction of the outer circumferential surface of the transfer cylinder. Can body to be printed 8
It has a length twice as long as the outer circumference of the body.

3a, 3b, 3c, 3d are transfer cylinders,
On the outer peripheral surface of each transfer cylinder, printing plates 4a, 4b, 4 having a printing surface whose length in the circumferential direction of the cylinder outer peripheral surface is equal to the outer peripheral length of the body of the can body 8 to be printed are provided.
c, 4d are arranged.

5a, 5b, 5c, and 5d are ink stations, which respectively correspond to the transfer cylinders 3a, 3b, 3c, and
3d, and the ink stored at the end of the ink station is supplied to the plate surface of each transfer cylinder via a large number of rolls. The ink stored in the ink station has the highest viscosity for the first layer of ink that is transferred to the can body first, and the viscosity is adjusted to lower in the order in which the ink is transferred.

Reference numeral 6 denotes a mandrel, which is placed near the periphery of a vertically rotating disk (hereinafter referred to as a mandrel wheel) 7 at equal intervals via a support 16 (see FIG. 2) that is movable in the diametrical direction of the mandrel wheel. A large number of rods (some of which are shown in FIG. 1) are arranged parallel to the drive shaft 13 of the mandrel wheel, and the mandrel 6 is held by a can holding mechanism (see FIG. 4), which will be described later. The can body 8 to be printed is held under pressure from the inner peripheral surface of the can body body, and is driven and rotated in synchronization with the transfer cylinder by a mandrel synchronized drive rotation mechanism (see FIGS. 2 and 3), which will be described later. .

In FIG. 1, reference numeral 9 denotes a can supply device for supplying the printed cans 8 to the mandrel 6, 10 denotes a finishing varnish coating roll for applying finishing varnish to the can bodies after overprinting, and 11 and 12 denote the above-mentioned units. This is a frame that supports the transfer cylinder, transfer cylinder, etc.

In FIG. 4, reference numeral 31 denotes a hollow mandrel shaft rotatably supported by a support base 16 provided on the mandrel wheel 7 so as to be movable in the diametrical direction thereof.
2a and a large diameter cylinder portion 32b,
The large-diameter cylinder portion 32b communicates with an air pipe 39, and the small-diameter rod guide portion 32a has a flange 33a at its tip, and the guide rod 3 has an air passage 33b communicating with the air pipe 40.
3 is inserted through the guide rod 33, and a piston member 34 that fits into the large-diameter cylinder portion 32b is fixed to the rear end of the guide rod 33. Between the one end side disk 26b of the joint 26,
A compression spring 35 is disposed, and a tapered portion 3 is further provided on the outer peripheral surface of the tip side of the mandrel shaft 31.
1' is formed, and the tapered part has a reverse taper formed on the inner circumferential surface that matches the tapered part, so that the outer circumferential surface can be tightly fitted to the inner circumferential surface of the body of the can to be printed (in this example,
can body holding members 36a, 36b, 36c
{See also FIG. 4b [C-C arrow view in FIG. 4a]} are bound by a snap spring 37 and fitted into an integral cylindrical body, and the can body holding members 36a, 36b , 36c are the guide rods 3
The guide rod 33 engages with the tip flange 33a of the guide rod 33, and by the reciprocating movement of the guide rod 33, the slide key 38 [also serves as a stopper for the can body holding member]. Refer to FIG. 4b], it is configured to be able to freely slide in the axial direction of the mandrel shaft while expanding and contracting its diameter, following the change in diameter of the mandrel shaft taper portion.

In Figure 2, 13 indicates frame 11 and frame 12.
(See Fig. 1) A mandrel wheel drive shaft is rotatably mounted on a column 14 that is fixed upright to a mandrel wheel.The end of the drive shaft 13 on the frame 11 side is connected to a drive device (not shown). The drive shaft has a hub 1 provided with an air supply port in order from the pillar 14 side.
5. Mandrel shaft 31 of the mandrel 6
A shaft 1 is provided corresponding to each of the mandrel wheel 7 and the mandrel shaft 31, each of which has a plurality of supporting stands 16 rotatably supported thereon at equal intervals on its periphery.
Wheel 19 rotatably supports 8 at its peripheral edge.
However, both are fixed with a key 20, and between the wheel 19 and the frame 11 is a two-stage ring gear 2 consisting of two integrally formed gears.
3 is loosely supported on the drive shaft 13 via the sleeve 22 and bearing 21, and one gear 23a of the two-stage ring gear is a pinion fixed to one end of the drive shaft 24 rotatably supported on the frame 11. 2
The other gear 23b of the two-stage ring gear meshes with the pinion 1 fixed to one end of the shaft 18 rotatably supported by the wheel 19.
7, and a disk 26a on one end side of the offset joint 26 is fixed to each of the other ends of the shaft 18, and a disk 26b on the other end side of the offset joint 26 is connected to the mandrel shaft 31 as described above. is fixed at the rear end of the

The misaligned joint 26 is such that when the overprinting device to which the present invention is directed, the mandrel wheel 7 rotates continuously without stopping when the can body and the transfer cylinders 1, 1' come into rolling contact, and therefore , in which the mandrel 6 holding the can body revolves while moving in the diametrical direction of the mandrel wheel 7 via the support base 16, and the axis of the mandrel shaft 31 and the axis of the shaft 18 move in parallel. , is used to drive and rotate the mandrel shaft at a constant speed even during the parallel movement. In this specific example,
As shown in FIG. 3 [a is a detailed sectional view, b is a view taken along the line B-B in a], three disks 26a, 26b, which operate according to the principle of a parallel crank mechanism,
26c and six links 26'a to 26'f are used.
The movement of the support base 16 in the diametrical direction of the mandrel wheel is carried out by a cam follower 29 provided at the upper part of the support base via a pin 28 being guided by a cam groove of a ring cam 30 fixed to the frame 11.

The operation of the apparatus according to the present invention will be explained below.

A can supply device 9 shown in FIG. 1 supplies the can 8 to a mandrel 6 disposed on a continuously rotating mandrel wheel 7. When the can body is fed to the mandrel, the guide rod 3 shown in FIG.
Air is sucked in through the air passage 33b of No. 3 and the air piping 40, and the can body is sucked so that the bottom inner surface of the can body comes into contact with the tip of the can body holding member 36, and then from the air piping 39 to the cylinder of the mandrel shaft. Air is supplied to the portion 32b, the piston member 34 compresses the spring 35 and moves, and the movement of the piston member also moves the guide rod 33, and the tip flange 33a of the guide rod 33 is moved.
Can body holding members 36a, 36b, 36c that engage with
The mandrel shaft taper portion 31' is guided by the sliding key 38 to enlarge its diameter, and at the end of the sliding movement, it comes into close contact with the inner circumferential surface of the can body and presses and holds the can body. As shown in FIG. 2, the mandrel is driven by a pinion 25, a two-stage gear 23, a pinion 17, a shaft 18, and a core by rotation of a shaft 24 connected to a drive device for the mandrel wheel 7 or another drive device. The can body, which is driven through the differential joint 26 and fitted onto the mandrel, has a circumferential speed that is synchronized with the circumferential speed of the transfer cylinder (however, the rotational speed is It rotates in the opposite direction). The can body fitted on the mandrel rotates on its own axis and revolves due to the rotation of the mandrel wheel 7, and reaches the contact start position with section 2a of the blanket 2 of the transfer cylinder 1, where the circumferential speeds of both are synchronized. Therefore, smooth contact is started, and after the start of contact, the can body rotates on the concentric trajectory of the transfer cylinder 1 while changing the revolution radius by moving the support base 16 in the diametrical direction of the mandrel wheel. Due to rotation, the rolling contact with the blanket 2a section is completed, and the transfer cylinder 3a is transferred to the outer peripheral surface of the can body.
The more transferred first layer ink is transferred, and by one subsequent rotation of the can body, the rolling contact between the blanket 2a section and the continuous blanket 2b section is completed, and the first layer ink is partially polymerized. Then, the second layer of ink transferred from the transfer cylinder 3b is transferred. When the can body finishes rolling contact with the section of blanket 2b, it moves to the section of blanket 2a.
The radius of revolution has returned to the point at which contact with the section started. After the can body has finished rolling contact with the blanket 2 of the transfer cylinder 1, it continues to rotate and revolve as it is, and reaches the position where it starts contacting the blanket 2c section of the transfer cylinder 1', and in the same manner as described above, it is moved to the transfer cylinder 3c. The ink of the third layer, which has been further transferred, is partially polymerized and transferred to the lower layer, and then the ink of the fourth layer, which has been transferred from the transfer cylinder 3d, is partially polymerized and transferred to the lower layer. After the can body has come into rolling contact with the blanket 2 of the transfer cylinder 1', it continues to rotate and revolve, and after being coated with finishing varnish by the finishing varnish coating roll 10, when it reaches a predetermined position on the conveyance path, At the same time as the air supply from the air piping 39 shown in FIG. The holding member 36 slides on the mandrel shaft tapered portion 31' while reducing its diameter, and the press holding of the can body is released. Then, air is discharged from the air passage 33b of the guide rod 33 via the air pipe 40, and the can body is is extracted from the mandrel 6.

In this embodiment, communication between the cylinder part 32b of the mandrel shaft and the atmosphere is established by a switching member 41 shown in FIG. 39 is blocked by the member 41, and the other end of the air path 39', which is bored in the switching member 41 and has one end open to the atmosphere, communicates with the upper side of the blocked air pipe. It is done by doing.

Since the present invention is constructed and operates as described above, it has the following features.

(1) The holding member of the can body holding mechanism provided on the mandrel is a cylindrical body that is in close contact with almost the entire inner peripheral surface of the can body, so that it can receive the transfer cylinder printing pressure evenly in the longitudinal direction of the can body. , it is possible to print evenly and clearly.

(2) Since the can body is driven and rotated in synchronization with the circumferential speed of the transfer cylinder, contact between the can body and the transfer cylinder occurs without impact, and the printing pressure at the start of contact does not become excessive. Therefore, the printing pressure in the direction of the outer circumferential surface of the can body is constant, and there is no risk of slipping between the can body and the transfer cylinder while they are in contact, so the printing quality is stable and high, and even if multiple transfer cylinders are used. Even when using this method, the transfer starting edges of each ink layer accurately match.

Incidentally, in the above embodiment, an example of a four-color overlapping printing device that does not require a drying process is explained in which two transfer cylinders are arranged in each of the two transfer cylinders, but the present invention is not limited to this format. In addition to the conventional apparatus that requires a drying process, the arrangement of transfer cylinders and transfer cylinders is also different, for example, when applying to four-color overlapping printing, there is a type in which four transfer cylinders are arranged in one transfer cylinder. It can be implemented in various ways, such as in a format in which one transfer cylinder is arranged for each transfer cylinder.

Furthermore, by disposing an elastic plate such as rubber (flexographic plate) in place of the blanket in the transfer cylinder, and by disposing a flat rubber plate, etc. in place of the plate in the transfer cylinder, the plate The body can roll directly into contact with the can body, allowing for clearer and more beautiful printing.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an embodiment of the overlapping printing device to which the present invention is applied, and FIG. 2 is an A-A diagram of FIG. 1.
A detailed sectional view showing a specific example of a mandrel synchronized drive rotation mechanism corresponding to the arrow view, FIG. 3a is a partial detailed sectional view of FIG. Fig. 4a is a partially enlarged detailed sectional view of Fig. 2 showing a specific example of the can body holding mechanism, and Fig. 4b is a view taken along the line C--C of a. In the figure, 1 and 1' are transfer cylinders, 2 is a blanket, 3a to 3d are transfer cylinders, and 4a to 4
d is a printing plate, 5a to 5d are ink stations, 6
1 is a mandrel, 7 is a mandrel wheel, 8 is a can body, 9 is a can body supply device, 10 is a finishing varnish coating roll, 11 and 12 are frames, 13 is a drive shaft of the mandrel wheel, 14 is a support column, 15 is a hub, 1
6 is a support base, 17 is a pinion, 18 is a shaft, 19 is a wheel, 20 is a key, 21 is a bearing, 22 is a sleeve, 23 is a two-stage ring gear, 24 is a shaft, 25
is a pinion, 26 is a center joint, 28 is a pin, 2
9 is a cam follower, 30 is a ring cam, 31 is a mandrel shaft, 31' is a tapered part of the mandrel shaft, 32 is a hollow part of the mandrel shaft, 33 is a guide rod, 34 is a piston member,
35 is a compression spring, 36a to 36c are can body holding members, 37 is a snap spring, 38 is a sliding key, 39 and 40 are air pipes, and 41 is a switching member.

Claims (1)

[Claims for Utility Model Registration] A large number of mandrels are horizontally arranged near the periphery of a vertically rotating disk at equal intervals through support stands that are movable in the diametrical direction of the vertically rotating disk. death,
A cylindrical can body is fitted onto the mandrel, and the can body is conveyed along a predetermined path by the rotation of the vertically rotating disk and the movement of the support base, and the outer peripheral surface of the body and the outer peripheral surface of the can body are transported. In an apparatus for overlapping printing on the outer peripheral surface of a cylindrical can body by rolling contact with a transfer cylinder coated with ink, each of the mandrels is rotatably supported by each of the supports. has a mandrel shaft, and
The mandrel shaft has a tapered portion formed on the outer circumferential surface and a reverse taper that matches the tapered portion on the inner circumferential surface, and is bound into an integral cylindrical body by a spring member so that the diameter can be expanded and contracted. A can body holding mechanism is provided which includes a plurality of holding members that are slidably fitted only in the axial direction of the mandrel shaft via guide members to the tapered portion of the shaft, and further, one end side is attached to the mandrel shaft of each of the mandrels. A fixedly installed misaligned joint, and the other end of the misaligned joint is fixed to one end and fixed to the drive shaft of the vertical rotating disk that rotatably supports a shaft with a pinion fixed to the other end. a two-stage ring gear that is loosely supported on the drive shaft of the vertical rotating disc, one gear meshing with each of the pinions, and the other gear meshing with the drive-side pinion; A device for overlapping printing on the outer peripheral surface of a cylindrical can body body, characterized in that it is equipped with a mandrel synchronized drive rotation mechanism.