JP2520386Y2 - Color printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a color printer for performing color printing by performing printing a plurality of times with different colors.

[Conventional technology]

In the conventional color printer, two types of methods are roughly used for the color material detection mechanism of the ink sheet. One method is shown in FIGS. 4 to 5. In the figure, 1 is a reflection type optical sensor, 2 is a reflective object, 3 is an ink sheet, and the reflection type sensor 1 and the reflective object 2 are provided at positions facing each other with a distance H therebetween. It has a function to detect the color material of. 3a is a supply side roll of the ink sheet 3, 3b is a take-up side roll, 4 is a thermal head, 5 is a platen roller, 6 is a supply side guide roller of the ink sheet 3, 7 is a take-up side guide roller, Reference numeral 8 is a lower mechanism, and 9 is an upper mechanism.
The reflection type optical sensor 1 is fixed to the upper mechanism 9,
The upper mechanism 9 is pivotally attached to the lower mechanism 8 by a fulcrum not shown.

The other method is a mechanism for detecting the color material of the ink sheet 3 by the transmissive optical sensor 10 as shown in the perspective view of the ink sheet color material detection portion in FIG. 3c
Is a color material applied to the ink sheet 3, and 3d is a detection mark for detecting the color material 3c.

Incidentally, FIG. 4 shows a state of printing, and FIG. 5 shows a state of waiting and color material detection.

Next, the operation will be described. In FIG. 5, the color material of the ink sheet 3 is detected, the thermal head 4 is separated from the platen roller 5 by a certain distance, and the ink sheet 3 is supplied from the supply side roll 3a and the supply side guide roller 6 , Is wound onto the winding-side roll 3b via the winding-side guide roller 7. During this period, the color material is detected by the reflective sensor 1 and the reflective object 2. On the other hand, in the case shown in FIG. 6, the transmission type optical sensor 10 detects the detection mark 3d provided on the ink sheet 3 to determine the color material 3c. During this period, the winding diameter of the supply-side roll 3a decreases and the winding diameter of the winding-side roll 3b increases with the use, but the conveyance path of the ink sheet 3 has a supply-side guide roller 6 and a winding-side guide roller. It is held in a fixed position by 7. Also,
As shown in FIG. 4, the thermal head 4 contacts the platen roller 5 at a constant pressure during printing, and the conveyance path of the ink sheet 3 changes.

[Problems to be solved by the device]

Since the conventional thermal printer is configured as described above, the ink sheet is conveyed within the limited detection distance of the reflective optical sensor regardless of whether the ink sheet is in the color material detection state or during printing. There has been a problem that a path has to be set and a constant conveying path has to be configured by the supply side guide roller and the winding side guide roller. Further, in the case of a transmissive optical sensor, there is an operational trouble that the ink sheet must be inserted into the light emitting / receiving area when the ink sheet is replaced.

The present invention has been made to solve the above problems, and the supply side guide roller and the winding side guide roller can be omitted, and the operability can be improved without the sensor interfering with the insertion of the ink sheet. The purpose is to obtain a thermal printer.

[Means for solving the problem]

In the thermal printer according to the present invention, a high-sensitivity light-emitting element with improved detection sensitivity and a high-sensitivity light-receiving element are individually arranged so as to face each other on the optical axis, and the distance between the elements is increased and The element is attached to the upper mechanism side which is pivotally attached to the lower mechanism. At the same time, the thermal head cover also serves as a guide in the ink sheet transport path.

[Action]

In the thermal printer according to the present invention, the distance between the high-sensitivity light-emitting element and the high-sensitivity light-receiving element is set to a distance sufficient to cover the fluctuation of the ink sheet running path due to the increase or decrease in the winding diameter of the ink sheet supply side roll and the winding side roll. The guide roller for the ink sheet is omitted. Further, since one of the elements is provided in the upper mechanism pivotally attached to the lower mechanism, the element does not interfere with the insertion of the ink sheet by opening the upper mechanism.

〔Example〕

Less than. One embodiment of the present invention will be described with reference to the drawings. In FIG. 1, FIG. 2, and FIG. 3, 31 is a high-sensitivity light emitting element,
Reference numeral 32 denotes a high-sensitivity light receiving element, both of which are provided with a distance L therebetween, and L> H. 3 is an ink sheet, 3a is a supply side roll, 3b is a winding side roll, 4 is a thermal head, 4a is a thermal head cover, 5 is a platen roller,
8 is a lower mechanism and 9 is an upper mechanism.
And the thermal head 4 is fixed to the upper mechanism 9,
The upper mechanism 9 is pivotally attached to the lower mechanism 8 by a fulcrum (not shown) as in the conventional case.

Next, the operation will be described. In FIG. 2, the color material of the ink sheet 3 is detected, and the thermal head 4
Is a detection mark applied to the ink sheet 3 while being separated from the platen roller 5 by a certain distance and being wound from the supply side roll 3a to the winding side roll 3b by a winding drive mechanism for the ink sheet 3 not shown. The above high sensitivity light emitting device
It is detected by 31 and the high-sensitivity light receiving element 32. Supply side roll 3a
Also, the winding diameter of the winding-side roll 3b changes with the lapse of use, and as shown in FIG. 1, even when the thermal head 4 contacts the platen 5 and shifts to the printing state, the ink sheet 3 The transport path of the line also varies greatly as shown by the solid line to the dot-dash line.
By adopting the high-sensitivity light-receiving element 32, the separation distance L can be sufficiently secured, the conveyance path is not obstructed, and the thermal head cover 4a of the thermal head 4 is being detected during the detection of the color material of the ink sheet 3 and during printing. The part plays a role of a guide for conveying the ink sheet 3.

FIG. 3 shows a state in which the upper mechanism 9 is opened. However, since the thermal head 4 and the high-sensitivity light receiving element 32 are retracted together with the upper mechanism 9, there is no obstacle to the attachment / detachment of the ink sheet 3.

In the above embodiment, the high-sensitivity light receiving element 32 is attached to the upper mechanism 9.
Although the high sensitivity light emitting element 31 is fixed to the lower mechanism 8 respectively, the high sensitivity light emitting element 32 is used instead of the high sensitivity light emitting element 32.
Instead of the high-sensitivity light emitting element 31 in the upper mechanism 9, the high-sensitivity light receiving element 32 may be fixed to the lower mechanism 8 respectively, and the same effect as the above-described embodiment is obtained.

[Effect of device]

As described above, according to the present invention, the light emitting element and the light receiving element as the photosensors for detecting the color material of the ink sheet are arranged so as to face each other independently, and the high sensitivity type is provided. In addition, since the guide in the ink sheet running path is substituted by the thermal head cover, the guide rollers on the supply side and the take-up side can be omitted, and one element can be rotated with respect to the lower mechanism. By being attached to the upper mechanism side which is movably pivotally attached, there is an effect that an inexpensive and improved operability can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic line sectional view showing an embodiment of the present invention in the state of printing, and FIG. 2 is a schematic line sectional view showing the same embodiment as FIG. 1 in the state of detecting a color material. 3 is a schematic line sectional view showing the same embodiment as FIG. 1 when the upper mechanism is opened, FIG. 4 is a sectional view showing a state of a conventional color printer during printing, and FIG. 5 is a color diagram of the conventional color printer. FIG. 6 is a sectional view showing a state during material detection, and FIG. 6 is a perspective view showing a conventional transmissive photosensor for color material detection of a color printer. In the figure, 3 is an ink sheet, 3a is a supply side roll, 3b is a winding side roll, 3c is a color material, 4 is a thermal head, 4a is a thermal head cover, 5 is a platen roller, 8 is a lower mechanism, and 9 is an upper part. A mechanism, 31 is a high sensitivity light emitting element, and 32 is a high sensitivity light receiving element. The same reference numerals in the drawings indicate the same or corresponding parts.

Claims (1)

(57) [Scope of utility model registration request] 1. A long ink sheet fed from a supply roll and a recording paper fed from a recording paper feeding means are overlapped at a predetermined portion, and a plurality of color regions of the ink sheet are overlapped to perform printing. In a color printer, a high-sensitivity light-emitting element is arranged on one side and a high-sensitivity light-receiving element is arranged on the other side so as to face the conveyance path of the ink sheet fed from a supply roll, and the one side of the high-sensitivity light emitting element is arranged. A color printer characterized in that an element and a thermal head are attached to an upper mechanism side which is rotatably pivoted with respect to a lower mechanism, and a thermal head cover also serves as a guide in an ink sheet conveyance path.