JPH0232450Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an ink transfer device that always supplies an optimum amount of ink to an ink ribbon. Conventionally, in a device that supplies ink to an ink ribbon to extend the printing life of the ink ribbon, if the ink ribbon is brought into direct contact with an ink carrier such as an ink roll, ink pad, or ink tank, the structure of the ink carrier causes damage to the ink ribbon. , a large amount of ink is supplied and the supply area or the entire circumference is over-impregnated with ink. In various types of impact printers that use ink ribbons, such as type type or wire dot type, excessive ink impregnation of the ink ribbon can cause blistering of the print, staining of the paper surface, smudging of the type, and staining of the type wire. The impregnated amount is generally 10 to 18 g/m ² , and as mentioned above, it is not preferable that the entire circumference is partially impregnated with ink. For this reason, the ink supply device is provided with a single ink transfer roll between the ink ribbon and the ink holder to adjust the ink supply amount and to prevent partial over-impregnation. However, even if these transfer rolls are provided as a single transfer roll, if an ink roll or ink pad is used as an ink carrier in the early stage of printing, the surface layer of these porous bodies will become over-impregnated due to ink impregnation. As a result, the amount of ink supplied temporarily increases compared to the printing equilibrium state, resulting in excessive ink impregnation of the ink ribbon due to the following reasons. When a smooth roll is used as an ink transfer roll, and when a material with a large contact angle to the ink is used, such as silicone resin, soft resin, polyacetal, polyethylene, or polypropylene, the amount of ink deposited on the roll is less than the printing consumption. In addition, the initial ink ribbon is over-impregnated in order to set the printing plateau condition. In addition, when using a roll with a flat or cross-knurled surface as an ink transfer roll, the knurls should be cut in order to limit the amount of ink supplied by depositing ink only on the tips of the knurling teeth. Printing equilibrium state is set and number of modules m = 0.2 to 0.8
mm is common. In knurling with such a small number of modules, the tooth grooves are small and shallow, so
Ink stays in the tooth grooves from the ink holder, and the flexible ink ribbon absorbs ink not only from the tips of the teeth but also in the tooth grooves due to capillary action, causing over-impregnation of the ink ribbon in the early stages of printing. This invention solves all the shortcomings of conventional transfer rolls, and from the beginning of printing,
Clear printing without bleeding can be obtained, and printing life can be extended by supplying an appropriate amount of ink to the ink ribbon. The present invention will be explained in detail using figures. FIG. 1 is a perspective view of an embodiment of the present invention, and FIG. 2 is a plan view thereof. The present invention is an ink transfer device that combines a roll 2 whose surface is in direct contact with an ink holder 1 and whose surface is knurled, an ink ribbon 4, and a smooth roll 3 whose surface is in direct contact with the knurled roll 2. The knurled roll 2 attaches ink to the tips of the teeth from the ink holder and transfers the ink to the smooth roll.The number of knurling modules is preferably 0.1 to 0.5 mm, which corresponds to ink consumption depending on printing conditions. to determine the number of modules. The smooth roll 3 is provided to selectively transfer only the ink attached to the tooth tips of the knurling roll 2 to the ink ribbon, and at the beginning of printing, the amount of ink supplied from the ink holder is large. Even if ink adheres to the grooves of the knurling teeth, the surface of the smooth roll only contacts the tips of the knurling teeth, so a certain amount of ink attached to the tips of the teeth can be removed regardless of the ink adhesion state of the knurling rolls. Can be transferred to ribbon.
Therefore, even when a large amount of ink is supplied from the ink holder at the beginning of printing, a single amount of ink is always supplied to the ink ribbon, so that over-impregnation of the ink ribbon does not occur at all. Materials for smooth rolls include polyacetal, ABS, polypropyl, polyethylene,
Futsuso resin, Futsuso rubber, silicone rubber, NBR,
Waretan rubber is preferred. In the ink transfer device that rotates (resistance) the transfer rolls 2 and 3 to the ink carrier roll 1 by the running friction of the ink ribbon 4, the knurled roll is slightly rotated to the smooth roll in order to transmit the driving force due to the running of the ink ribbon. Rubber-based materials such as soft rubber, NBR rubber, urethane rubber, and silicone rubber are advantageous, and rubber hardness of 30° to 70° is preferable. In this way, there is little change in the ink supply amount and a large amount of ink is not consumed initially, so the print density changes very gradually and the print life is also shortened compared to an ink transfer device that uses a single transfer roll. The ink transfer device of
Increases to 20-30%.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of one embodiment of the present invention. FIG. 2 is a plan (front) view thereof. 1... Ink holder, 2... Knurling roll, 3... Smooth roll, 4... Ink ribbon.

Claims (1)

[Scope of utility model registration request] Ink ribbon, ink roll, ink pad,
An ink transfer device that supplies ink from an ink carrier such as an ink tank, wherein the ink is transferred and supplied from the ink carrier to a knurled roll, a smooth roll, and an ink ribbon in this order.