JPH02259Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a pad printing device suitable for printing curved objects.

Pad printing, as shown in Figure 1, involves first transferring the ink impregnated into the characters and pattern portions 2 of the plate 1 to the pad body 3, and then moving the ink transferred to the pad body by a printing machine. , transfer printing is performed by pressing onto a printing material 4 which is a curved surface. On the other hand, Japanese Patent Publication No. 57-3508 proposed a method for printing curved surfaces, in which a sheet on which a printing ink layer was formed was stretched over another frame, and the back surface of the sheet was pressed by fluid pressure to form a curved surface. There was a method of transferring the ink to printed matter, but this method did not use a pad, but instead used a sheet, and this flat sheet was pressed by fluid pressure using a device with a complicated mechanism and an airtight chamber, and the device was also single. It took a lot of time and effort.

Conventionally, solvent-resistant solid elastic bodies made of silicone resin, urethane resin, gelatin, etc. have been used as pad bodies for pad printing, but their elasticity is
Due to the shape of the printing material, it has a fairly high solid density and low warmth to prevent blurring of letters and the resulting ink bleeding of printed letters, so during printing and pressure transfer by the printing machine, the pads are Only the flexibility of the surface portion could be obtained, and the curved surface of the printing medium could only be obtained within a small range.

Therefore, it was not possible to provide versatility for many types of printing materials with one pad.
A disadvantage is that a dedicated pad must be prepared for each printing material having a different curvature.

In this invention, the pad body has been improved from a solid elastic body with low flexibility to a cup-shaped elastic body with extremely high flexibility, as shown in Figures 2 and 3, and the curvature of the transfer surface can also be changed. This provides versatility in printing on various types of substrates with different curvatures.

Next, one embodiment of the present invention will be described in detail below based on the accompanying drawings.

Reference numeral 5 denotes a pad body, which is the most important part of the pad printing apparatus of the present invention.The pad body is made of silicone resin, urethane resin, gelatin, etc., and is molded into a cup shape, and the peripheral wall is flexible enough to bend inward. The pad main body has a bottom surface 7 formed into a convex surface to easily adapt to changes in the curved shape of the printing material 6. The upper end opening of the pad body is fixed to the fixing plate 9 with adhesive, mounting hardware, etc., and is closed to form the pad body.

The fixed plate 9 is fixed to the tip of the movable plate 10 and attached to the printing press, and operates the pad 5 by moving vertically and horizontally.

Next, an adjustment member for changing the curvature of the bottom surface 7 of the pad body 5 will be explained. Reference numeral 11 denotes a guide screw having a threaded portion formed on the inner surface of the cylinder, which protrudes into the hollow of the pad main body 5, and is fixed to the mounting plate through the guide screw.

Reference numeral 12 denotes an adjustment screw, which is comprised of a large diameter threaded portion 13 that is screwed into the guide screw 11, and a small diameter portion 15 that hangs below the large diameter portion 13 through a stepped portion 14 toward the bottom surface of the pad body. It is fixed so that it can be moved up and down within the pad hollow by adjusting the screw engagement with the guide screw.

Reference numeral 17 denotes a relay that comes into contact with the inner bottom surface of the pad body 5, and its upper end abuts against the lower end surface of the stepped portion 14 and stops there.

The relay is slidably fitted into the small diameter portion 15, and is always held against the inner bottom surface of the pad body by a coil spring 19 held between the stepped portion 14 and the flange 18 of the relay 17. The curvature of the inner bottom surface is increased by press-contacting the inner bottom surface.

Note that the sliding stroke of the relay is predetermined. In the figure, reference numeral 16 denotes a rotation hole for adjusting the rotation of the adjustment screw 12 from the outside of the upper end with a box wrench.

Note that the mechanism for changing the curvature of the bottom surface of the pad 5 is not limited to the above, and instead of the guide screw and adjustment screw configuration described above, an adjustment rod may be used, and the adjustment rod may be moved from a fixed plate into the pad hollow in multiple stages. It may be configured to be pushed in. Also, it can be adjusted from the outer periphery of the fixed plate while remaining attached to the movable plate.

The operation of the pad printing apparatus of the present invention having the above configuration is as follows.

If the curvature of the printing surface of the printing material 6 becomes large and cannot be accommodated by the curvature of the pad bottom surface 7 adjusted in FIG. 2, as shown in FIG. 4, adjust the adjustment screw 12 as shown in FIG. The inner bottom surface of the pad is brought out by a relay 17, and the curvature of the pad bottom surface 7 is increased to correspond to the curvature of the printing medium 6.

When the pad adjusted in this way is moved by a printing machine (not shown) and pressed against the fixed plate, the inner bottom surface of the pad is only elastically pressed against the relay 17 via the coil spring 19. The pad bottom surface 7 easily deforms to correspond to the curved surface of the printing material, and as shown in FIG. 4, the printing surface is compressed and the ink transferred from the plate 8 onto the bottom surface is transferred and printed onto the printing material. do. The curvature can be changed freely within a predetermined range depending on the degree of protrusion of the relay.

As described above, the pad printing device of the present invention has the following features: (1) By attaching the pad body to the movable plate of the printing machine via the fixed plate, the pad body can be printed with a single machine by simply moving it horizontally and vertically. By transferring the printing ink to the paper, printing on the curved surface of the printing material can now be done easily and reliably.

(2) The pad body, which is the most important part, is made of a highly flexible material, and the inside is hollowed out in the shape of a cup so that the bottom surface of the pad body can be pushed outward and curved through an adjustment member and a relay in the inner cavity. Because of this, it does not require complicated airtight rooms or sheet tension frames like the conventional example.
The desired curvature of the inner bottom surface of the pad body can be obtained by simply pushing down the movable plate without requiring any fluid pressurizing device or the like. The overall structure is simple and operation is easy.

(3) Since the relay in the pad main body expands and contracts in an adjustable manner, a curved surface that corresponds to the curved surface of the printing medium more delicately and accurately can be obtained compared to fluid pressurization.

(4) The pad body is thinner and requires less material than conventional models, making it an extremely practical idea.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram of a pad printing method, FIGS. 2 and 3 are longitudinal sectional views of the pad of the present invention, and FIG. 4 is a schematic diagram of a pad printing method using the pad of the present invention. 5... Pad body, 6... Printing material, 8...
Plate, 9... fixed plate, 17... relay, 19... spring.

Claims (1)

[Scope of utility model registration request] The pad main body, which transfers printing ink from the plate to the curved surface of the printing material, is made of a flexible, solvent-resistant elastic material and is hollowed out inside to form a cup-like shape, and the pad body has a cup-like shape with an interior hollowed out. An adjusting member having a predetermined vertical stroke is installed vertically on a fixed plate attached to the opening, and an extendable relay is installed between the adjusting member and the bottom surface of the pad body via a spring to adjust the curvature of the bottom surface of the pad body. A pad printing device in which the fixed plate is integrally fixed to a movable plate provided in the printing press and moves horizontally and vertically to transfer the ink and print on the printing material. .