JP4116733B2 - Bar code printer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bar code printing apparatus, and in particular, for printing various information on a printing medium having various width sizes and thicknesses inserted between a platen roller having a printing medium transfer means and a thermal head. This relates to a barcode printing apparatus.
[0002]
[Prior art]
A conventional bar code printer 1 will be described with reference to FIGS. 2 and 3 by taking a thermal transfer printer as an example.
[0003]
FIG. 2 is a conventional printing unit of the barcode printing apparatus 1, and FIG. 3 is a schematic explanatory diagram of the barcode printing apparatus 1.
[0004]
In the figure, reference numeral 2 denotes a print medium. The print medium 2 is loaded in the form of a roll in the print medium supply section 7 and can be fed out as the print medium 2 is printed and transported. As the printing medium 2, in addition to a thermal transfer type label or tag using a thermal transfer ribbon or the like, there are a thermosensitive coloring label and tag, and a label without a mount.
[0005]
Reference numeral 3 denotes a thermal transfer ribbon. The thermal transfer ribbon 3 includes a thermal transfer ribbon supply unit 8 around which an unused thermal transfer ribbon 3 is wound, and a thermal transfer ribbon winding unit 9 that winds up the used thermal transfer ribbon 3. It is stretched between them.
[0006]
Reference numeral 4 denotes a platen roller. The platen roller 4 is rotatably provided with a platen roller shaft as a support shaft. A head support 6 for supporting the thermal head 5 is a support shaft of the head support 6. And is fixed to the barcode printing apparatus 1 by a head opening / closing lever (not shown) or the like via a compression spring 10 between the thermal head 5 and the thermal spring 5.
[0007]
Reference numeral 5 denotes a thermal head. The thermal head 5 is rotatably held on a support shaft provided on the head support 6, and is biased by a plurality of compression springs 10 between the thermal support 5 and the head support 6. Pressed against the platen roller 4.
[0008]
The barcode printing apparatus 1 configured as described above superimposes the thermal transfer ribbon 3 on the printing medium 2 and sandwiches them between the platen roller 4 which also serves as a transfer means and the thermal head 5, and a drive motor (not shown). The platen roller 4 is rotated by the rotation of the platen roller 4 at the same time, and heat is transferred from the ink on the thermal transfer ribbon 3 to the print medium 2 by a heating element (not shown) of the thermal head 5 that generates heat based on the print data pattern. ing.
[0009]
[Problems to be solved by the invention]
By the way, in the barcode printing apparatus 1 having the above configuration, as shown in FIG. 2, when the printing medium 2 is less than the full width dimension of the thermal head 5, a material having a high frictional force such as silicon or rubber. Because the platen roller 4 directly contacts the thermal head 5, a large load is applied to the rotation of the platen roller 4, and the non-uniform pressure is applied to the heating elements of the thermal head 5, causing the skew of the print medium 2. Thus, the configuration using the thermal transfer ribbon 3 causes a problem that the thermal transfer ribbon 3 is wrinkled and the print quality is deteriorated.
[0010]
The present invention has been made in view of the above problems, and a first object of the present invention is to insert a thermal head provided across the width direction of a print medium and a platen roller facing the head. It is an object of the present invention to provide a barcode printing apparatus that enables a printing medium to be in proper contact with the thermal head.
[0011]
A second object of the present invention is to provide a bar code printing apparatus capable of performing proper printing even when a printing medium of a different size is loaded on the thermal head.
[0012]
A third object is to prevent deterioration in print quality, to reduce the load on the driving means for transporting the print medium, to prevent the skew of the print medium, and in the thermal transfer printer using the thermal transfer ribbon, Another object of the present invention is to provide a bar code printing apparatus that can reduce the occurrence of the above.
[0013]
[Means for Solving the Problems]
That is, the present invention provides a barcode printing apparatus that loads a printing medium having a printing surface and a non-printing surface and performs printing on the printing surface, and has a plurality of heating elements and traverses in the width direction of the printing medium. a thermal head provided, wherein the platen roller disposed opposite to the thermal head, the thermal head and the platen roller and spacing one or more provided on one end side outer circumference of the platen roller in order to maintain a constant A bar code printing apparatus.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Next, a barcode printing apparatus 1 according to an embodiment of the present invention will be described with reference to FIG. However, the same components as those described in the prior art are denoted by the same reference numerals, and detailed description thereof will be omitted.
[0015]
FIG. 1 is a schematic explanatory view of a printing unit 21 showing an embodiment of the present invention. The printing unit 21 is substantially the same as a conventional printing unit, and includes a printing medium 2, a thermal transfer ribbon 3, a platen roller 4, a thermal printing unit. The printing unit 21 further includes one or more sleeves 12 (a small diameter sleeve 12a, a medium diameter sleeve 12b, and a large diameter sleeve 12c). .
[0016]
The sleeve 12 includes a small-diameter sleeve 12a composed only of a cylindrical portion, a medium-diameter sleeve 12b having a flange portion at one end, and a large-diameter sleeve 12c.
[0017]
The small-diameter sleeve 12a is fixed to the outer periphery of one end of the platen roller 4, and the thickness and length of the small-diameter sleeve 12a is thermal between the print medium 2 and the small-diameter sleeve 12a when the thinnest print medium 2 is used. The thickness and length are such that the pressing force of the head 5 can be evenly distributed.
[0018]
The material is made of, for example, hard resin, and its surface has a smaller coefficient of friction than that of the platen roller 4 and is coated with, for example, silicone resin in order to make the material close to the surface of the print medium 2 or the thermal transfer ribbon 3. Can be configured.
[0019]
Further, the medium diameter sleeve 12 b is provided so as to be slidably inserted along the axial direction of the platen roller 4 on the outer peripheral surface of the small diameter sleeve 12 a and to rotate integrally with the rotation of the platen roller 4. .
[0020]
The large-diameter sleeve 12c has the same action as the medium-diameter sleeve 12b, and the outer peripheral surface of the medium-diameter sleeve 12b is extrapolated so as to be slidable along the axial direction of the platen roller 4. It is possible to rotate integrally with the rotation of 4.
[0021]
This flange is a knob that makes it easy to set the sleeve 12 having the same thickness as the print medium 2 or the print medium 2 and the thermal transfer ribbon 3 in order to keep the distance between the platen roller 4 and the thermal head 5 constant. To play the role.
[0022]
As described above, when the width of the print medium 2 is less than the full width of the sleeve 12, the distance between the platen roller 4 and the thermal head 5 is a thickness that combines the print medium 2 and the thermal transfer ribbon 3. The sleeve 12 is a combination of the sleeves 12a to 12c. For example, in FIG. 1, the sleeves 12b and 12c are slid in the left direction in the drawing along the axis of the platen roller 4 so as to select all of the small diameter sleeve 12a, medium diameter sleeve 12b, and large diameter sleeve 12c. The medium 2 and the sleeve 12 are set so that the pressing force of the thermal head 5 can be evenly distributed.
[0023]
Thus, since the head pressing force applied to the entire platen roller 4 is made more uniform, the skew of the print medium 2 can be prevented. In addition, in a thermal transfer type printer using a thermal transfer ribbon, it becomes possible to prevent wrinkles from occurring on the ribbon, and an appropriate print quality can be obtained.
[0024]
Also, with the above configuration, the area where the platen roller 4 and the heat generating element of the thermal head 5 are in direct contact can be reduced, and the torque required for the rotation of the platen roller 4 can be reduced.
[0025]
In the above embodiment, the case where the sleeve 12 is composed of three parts of the large diameter, the medium diameter, and the small diameter sleeve is illustrated, but the present invention is not limited to this, and the print medium alone or the print medium and the thermal transfer ribbon are combined. There are various combinations that can achieve different thicknesses.
[0026]
【The invention's effect】
As described above, according to the present invention, since the thermal head can contact the print medium with uniform pressure, it is possible to reduce the problem that the ribbon is wrinkled when the print medium is skewed or the thermal transfer ribbon is used. At the same time, the contact area between the platen roller having a high frictional force and the thermal head can be reduced from the configuration using the sleeve, so that smoother rotation of the platen roller and more appropriate printing can be obtained.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a printing unit 21 according to an embodiment of the present invention.
FIG. 2 is an explanatory diagram of a conventional printing unit 11;
FIG. 3 is a schematic explanatory diagram of a conventional barcode printing apparatus 1;
[Explanation of symbols]
1 Barcode printing device (thermal transfer printer, Fig. 3)
2 Printing media (continuous label)
3 Thermal Transfer Ribbon 4 Platen Roller 5 Thermal Head 6 Head Support 7 Print Medium Supply Unit 8 Thermal Transfer Ribbon Supply Unit 9 Thermal Transfer Ribbon Winding Unit 10 Compression Spring 12 Sleeve 12a Small Diameter Sleeve 12b Medium Diameter Sleeve 12c Large Diameter Sleeve 21 Invention printing part

Claims (1)

In a barcode printing apparatus for loading a printing medium having a printing surface and a non-printing surface and printing on the printing surface,
A plurality of heating elements, a thermal head provided across the width direction of the printing medium, a platen roller provided to face the thermal head, the distance between the platen roller and the thermal head barcode printing apparatus characterized by having a one or more sleeves which are provided on one end side outer circumference of the platen roller in order to keep constant.

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