JPH0292676A - Ink ribbon position detector - Google Patents

Abstract

PURPOSE:To improve the detecting accuracy of a ribbon position and to reduce the cost of position detecting means by bringing a reflecting plate close to the means by allowing the plate to protrude from a supporting member in a state that the moving position of an ink ribbon is detected, and retreating the plate into the member in a printing state. CONSTITUTION:In order to avoid the contact with a clamper 16a at the time of detection of the position of an ink ribbon 17, a thermal head 11 is separated from a platen drum 16. Thus, when a photosensor 13 is also moved in a direction separating from the drum 16, a slider 27 protrudes from a reflecting plate holder 26, a reflecting plate 15 is moved in a direction of approaching the photosensor 13, and a distance l between both is set, for example, to approx. 1mm. Accordingly, an inexpensive photosensor having a short focal length can be used to detect the position. A marker 19 disposed on the ribbon 17 is detected, the drum 16 is rotated, and the clamper 16a is moved to a position where the contact with a thermal head 11 is avoided. Then, the head 11 press- adheres to the drum 16, and set to a printable state.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention is applied to, for example, color video printers that use color ink ribbons to record television images in color using a thermal transfer method. The present invention relates to an ink ribbon position detection device.

(Prior Art) As is well known, in order to obtain a proper color image with a thermal transfer color printer such as a color video printer, the leading edge of the recording paper and the leading edge of each color ink area of the ink ribbon (ink sheet) must be aligned accurately. It is important to feed the ink ribbon so that it corresponds to the transfer position in an aligned state.

Therefore, conventionally, as shown in FIG. 4, for example, a reflective detecting element (ribbon movement position detecting means, e.g., a photo sensor) 13, 13 is attached to the tip of the thermal head 11 via a sensor plate 12, and the sensor plate A reflection plate 14 is arranged above the photo sensor 12 at a predetermined distance, and on this reflection plate 14 are arranged reflection plates 15 and 15 that reflect the light emitted from the photosensors 13 and 13, respectively. The light from the photosensor 13.13 is reflected by the reflection plate 15.15, and the distance between the platen drum 16 and the thermal head 11 depends on whether the reflected light is received by the photosensor 13.13. The moving position of the ink ribbon 17 is detected. In this case, as shown in FIG. (Y).

Magenta (M), cyan (C) color ink area 1
8 are arranged in sequence. In addition, each color ink area 1
8 (border area), the next color ink area 1
Markers 19 are provided at one end, the other end, or both ends of the boundary portion depending on the color of the ink of No. 8 to block light from the photosensors 13 and 13. This marker 19 is
Due to the movement of the ink ribbon 17, the photo sensor 13.1
3 and the reflector plate 15.15.
- The light from the photosensor 13.13 is blocked. Therefore, 1-Food sensor 13.13
When the light from the marker 19 is blocked by the marker 19, the photo sensor 13.13 is prevented from receiving the light, so that the marker 19 is detected and the moving position of the ink ribbon 17 is detected. It has become.

Below, the detection operation of the marker 19 will be specifically explained with reference to FIG. In this case, the platen drum 1
6 is provided with a clamper 16a4 for wrapping and holding the recording paper around the drum 16. That is, when detecting the marker 19, in order to avoid contact between the clamper 16a and the thermal head 11, the thermal head 11 must be moved from the broken line position M (during printing) shown in the figure to the solid line position shown in the figure, and pulled away from the platen drum 16. Must be.

In this case, the photosensor 13.13 is attached to the thermal head 11 via the sensor plate 12. For this reason, the photosensor 13.13 also has a reflection plate 15.
15, the photosensor 13.13 and the reflector 1
5.15 is moved to a position where the distance l between the two is about 5 mm.

On the other hand, the ink ribbon 17 is pulled out from the supply reel 17a, passes between the photosensor 13.13 and the reflection plate 15.15, and is wound up by the take-up reel 17b.

In this state, the photosensor 13.13 emits light onto the ink ribbon 17, and at this time, the color ink area 18 of the L ink ribbon 17 is illuminated by the photosensor 13.13.
and the reflecting plate 15.15, the light from the photosensor 13.13 described in - passes through the ink ribbon 17 and is reflected by the reflecting plate 15.15.
The light is received by 3.13. And ink ribbon 17
When the marker 19 is positioned between the photosensor 13.13 and the reflecting plate 15.15 due to the movement of be hindered.

In this way, the marker 19 is detected by blocking the reflected light to the photosensors 13, 13, and the position of the ink ribbon 17 is detected.

Then, the marker 19 is detected, and the platen drum 1
6 is rotated and the clamper 16a is moved from the solid line position shown in the drawing to the broken line position shown in the drawing, the thermal head 11 is moved by a drive mechanism (not shown) and pressure 4 is applied to the platen drum 16.
'1 will be given. Then, due to the movement of the thermal head 11, the photosensor 13°13 is moved to the position shown by the broken line in the figure.
It is now set to printable state.

However, in the above method, in order to avoid contact between the clamper 16a of the platen drum 16 and the thermal head 11, the photo sensor 13.
It is necessary to increase the distance between the reflector 15 and the reflector 15. In this case, since the distance between the photosensor 13.13 and the reflector 15.15 is long, it is necessary to use an expensive long-focus type photosensor 13.13 to detect the moving position of the ink ribbon.
3.13 had to be used, which hindered price reduction. In addition, in order to prevent detection errors due to manufacturing errors in mechanical parts, the accuracy of each part is strict, and highly accurate positioning adjustment is required.

(Problems to be Solved by the Invention) In this invention, since the distance between the photosensor and the reflecting plate is increased when detecting the moving position of the ink ribbon, a long focus type photosensor must be used. In order to prevent detection errors due to manufacturing errors in mechanical parts, the precision of each part is strict.
This was done to eliminate the drawback of requiring highly accurate positioning adjustment, etc., and does not depend on parts accuracy etc.
An object of the present invention is to provide an ink ribbon position detection device that can improve the accuracy of detecting the ribbon position on a product, and also reduce the price by making it possible to use an inexpensive short-focus type ribbon movement position detection means. It is said that

[Structure of the Invention] (Means for Solving the Problems) In the ink ribbon position detection device of the present invention, color ink areas of different colors are sequentially arranged in the longitudinal direction of a translucent film base, and each An ink ribbon provided with a marker made of a light-shielding member at the boundary of the color ink area, a moving means for moving the ink ribbon in the longitudinal direction, and a moving path of the ink ribbon moved by the moving means. a reflective plate disposed at one end; and a reflective plate provided at a position opposite to the reflective plate across the ink ribbon to receive reflected light transmitted through the ink ribbon and reflected by the reflective plate; ribbon movement position detection means whose reception of the light is blocked by a marker disposed on the ink ribbon, and in a printing state in which the thermal head is brought into contact with the platen drum, the ribbon movement position detection means is connected to the reflection plate. In an ink ribbon movement position detection state in which the thermal head is placed close to the platen drum and separated from the platen drum, the ink ribbon position detection device is configured such that the ribbon movement position detection means is separated from the reflection plate. The reflective plate is provided movably relative to a support member, and in a state where the moving position of the ink ribbon is detected, the reflective plate protrudes from the support member and is brought close to the ribbon moving position detecting means, and in a printing state, the reflector plate is arranged to be movable relative to the platen of the thermal head. The reflector is configured to be retracted into the support member by the ribbon movement position detecting means as the ribbon moves into contact with the drum.

(Function) With the above configuration, the distance between the ribbon movement position detecting means and the reflecting plate is shortened in the state of detecting the movement position of the ink ribbon, and the movement position of the ink ribbon can be accurately detected.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIGS. 1 and 2 schematically show an ink ribbon position detection device according to the present invention.

This ink ribbon position detection device includes a platen drum 16
A photo sensor (ribbon movement position detecting means) 13 is installed in a thermal head 11 that is movable in the vertical direction by a drive mechanism (not shown) via a sensor plate 12, and a photo sensor (ribbon movement position detecting means) 13 is disposed opposite to the photo sensor 13. The reflector plate 15 is provided as a reflector.

” - The food sensor 13 consists of a light projector that projects light onto the ink ribbon 17 moving in the direction of the arrow in the figure, and a light receiver that receives the reflected light projected from the projector and reflected by the reflector plate 15. It is configured.

The reflecting plate 15 is movably supported by a reflecting plate holder (supporting member) 26. That is, as shown in FIG. 3, the reflecting plate 15 is attached to the bottom surface of the slider 27. The slider 27 is provided with a guide support column 27a on its upper surface, and locking hooks 27b, 27b on both upper side surfaces. The reflector holder 26 also includes the slider 2.
An opening 26a into which the entire slider 7 can be inserted is formed, and locking claws 27b of the slider 27 are provided on both sides of the bottom surface (the side facing the sensor 13) of the opening 26a.
Stoppers 26b, 26b to which 27b is locked are provided. Then, the opening 26a of the reflector holder 26
Insert the slider 27 into the reflector holder 2 with the compression spring 28 arranged around the outer periphery of the support column 27a.
A lid 2 is placed on the top surface of the lid 2 so as to cover the opening 26a.
9 is fixed in place.

Thus, the slider 27 is moved downward within the opening 26a of the reflector holder 26 by the restoring force of the compression spring 28, and the locking pawls 27b, 27b are locked with the stoppers 26b, 26b. Opening 26a
By protruding from the bottom surface of the reflector plate 15, the reflector plate 15 can be moved to a position close to the photosensor 13. Furthermore, by applying a light load of about 10 g to 20 g to suppress the compression spring 28, the slider 27 can be easily moved through the opening 26a of the reflector holder 26.
It can be pushed inside. in this case,
A strut 27a provided on the slider 27 is configured to protrude and escape through an opening 29a formed in the lid 29.

On the other hand, as shown in FIG. 1, the ink ribbon 17 is pulled out from the supply reel 17a and wound through a moving path between the thermal head 11 and the platen drum 16 and between the photosensor 13 and the reflection plate 15. It is adapted to be wound up by a take-up reel (moving means) 17b.

In this case, the winding load torque of the take-up reel 17b is set to a sufficiently large value.

Although not shown in the figure for convenience, the photosensor 13 and the reflector 15 are provided corresponding to the paths along which the markers 19 disposed at one end and the other end of the ink ribbon 17 move, respectively. It is now possible to

FIG. 1 shows the state of the ink ribbon position detection device during printing. In this state, the thermal head 11 is brought into contact with the platen drum 16 by a drive mechanism (not shown), so that the slider 27 to which the reflection plate 15 is attached is moved in the direction of the arrow shown in the figure by the sensor plate 12 supporting the photosensor 13. Being pushed up. In this case, the compression spring 28 is set to a light load of approximately 10 g to 20 g. Therefore, the compression spring 28 is easily compressed, and the slider 27 is housed in the reflector holder 26.

In the state 1-, for example, by driving the thermal head 11 according to the color information of the television image, an image is formed on the recording paper with ink in the color ink area 18 of the ink ribbon 17 according to the color information. It will be done. In this case, the ink ribbon 17 will be sandwiched between the reflecting plate 15 and the photosensor 13;
By setting the winding torque of the take-up reel 17b of the ink ribbon 17 to a sufficiently large value, it is considered that movement of the ink ribbon 17 will not be hindered.

FIG. 2 shows the state of the ink ribbon position detection device when detecting the moving position of the ink ribbon 17. In this state, the thermal head 11 is separated from the platen drum 16 by a drive mechanism (not shown), and the clamper 16a for wrapping and holding the recording paper around the platen drum 16 is prevented from coming into contact with the thermal head 11. It is prevented. That is, when detecting the position of the ink ribbon 17, the thermal head 11 is pulled away from the platen drum 16 to avoid contact between the clamper 16a and the thermal head 11. In this case, the photosensor 13
is attached to the thermal head 11 via a sensor plate 12. Therefore, the above thermal head 1
1, the photosensor 13 is also moved in a direction away from the reflecting plate 15.

, 1- When the photo sensor 13 is moved, the slider 27 is protruded from the reflector holder 26, so that the reflector 15 is moved in a direction closer to the photosensor 13. That is, the slider 27 is projected from the reflector holder 26 by the return force of the compression spring 28, and thereby the reflector 15 is moved in a direction closer to the photosensor 13. In this case, the distance M between the photosensor 13 and the reflection plate 15 is set to about 1 tnm, for example. In this way, when detecting the position of the ink ribbon 17, the distance between the photosensor 13 and the reflecting plate 15 is set to about 1 m.
By bringing them close to about m, it becomes possible to use an inexpensive photosensor (reflective detection element) with a short focal length for position detection.

Furthermore, by shortening the distance between the photosensor 13 and the reflection plate 15, the marker 19 on the ink ribbon 17 can be easily detected, so the position of the ink ribbon can be easily detected regardless of component accuracy. accuracy can be improved.

When the photosensor 13 emits light onto the ink ribbon 17 and the color ink area 18 of the ink ribbon 17 is positioned between the photosensor 13 and the reflection plate 15, the light from the photosensor 13 is emitted. The light passes through the ink ribbon 17, is reflected by the reflection plate 15, and is received by the photosensor 13. When the marker 19 is positioned between the photosensor 13 and the reflection plate 15 by the movement of the ink ribbon 17, the photosensor 13
The light is blocked by the marker 19 and the photo sensor 13
reception of light is obstructed. In this way, by blocking the reflected light to the photosensor 13, the marker 19 is detected and the position of the ink ribbon 17 is detected. That is, when detecting the marker 19, the light from the sensor 13 is blocked by the marker 19 and does not enter the sensor 13, so the marker 19 can be detected by the change in the output of the sensor 13, and the position of the marker 19 can be determined. By detecting changes in the output of the sensor 13, it is possible to detect the tip position of the color ink area 18 following the detected marker 19.

In addition, in the case of this embodiment, since the sensor 13 whose output is changed differs depending on the position (one end, the other end, or both ends) of the marker 19 disposed on the ink ribbon 17, the marker 19
The tip position of the color ink area 18 following , and the area 18
It is said that it is possible to detect the color of ink.

In this way, the marker 19 is detected, the platen drum 16 is rotated, and the clamper 16a is moved to the thermal head 11.
When the thermal head 11 is moved to a position where contact with the platen drum 16 is avoided, as shown in FIG. be done.

As described in 1., when the moving position of the ink ribbon is being detected, the position of the reflecting plate is moved so as to be close to the photosensor that is moved as the thermal head moves away, and We are trying to shorten the distance between. This makes it possible to accurately detect the position of the ink ribbon, and also allows the use of an inexpensive short focus type photosensor. Therefore, the accuracy of ink ribbon position detection can be easily improved regardless of component accuracy.1. This makes it possible to reduce the cost of the device.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without departing from the gist of the invention.

[Effects of the Invention] Second, as described in detail, according to the present invention, it is possible to improve the detection accuracy of the ribbon position on the container, regardless of component precision, and to use an inexpensive short focus type ribbon. By making it possible to use the moving position detecting means, it is possible to provide an ink ribbon position detecting device that can be manufactured at a low cost.

[Brief explanation of drawings]

1 and 2 show an ink ribbon position detection device which is an embodiment of the present invention. FIG. 1 is a side view showing the state of the ink ribbon position detection device during printing, and FIG. A side view showing the state of the ink ribbon position detection device when detecting the ribbon position, FIG. 3 is an exploded perspective view shown to explain the movable mechanism of the reflector, and FIG. 4 shows the configuration of a conventional ink ribbon position detection device. A perspective view showing
FIG. 5 is a perspective view showing an example of the configuration of an ink ribbon, and FIG. 6 is a side view shown for explaining the detection operation of a conventional ink ribbon position detection device. 11... Thermal head, 13... Photo sensor (
(ribbon movement position detection means), 15... reflection plate, 16.
...Platen drum, 17...Ink ribbon, 18.
...Color ink area, 19...Marker, 17a...
- Supply reel, 17b... Take-up reel (moving means), 26... Reflector holder (supporting member), 27...
Slider, 28... compression spring.

Claims (1)

[Claims] An ink ribbon in which color ink areas of different colors are sequentially arranged in the longitudinal direction of a translucent film base, and a marker made of a light-shielding member is provided at the boundary between each color ink area. a moving means for moving the ink ribbon in its longitudinal direction; a reflecting plate disposed at one end of a moving path of the ink ribbon moved by the moving means; and a reflecting plate for moving the ink ribbon so as to face the reflecting plate. Ribbon movement position detection, which is provided at a sandwiched position and receives reflected light transmitted through the ink ribbon and reflected by the reflector, and where reception of the light is blocked by a marker provided on the ink ribbon. means, in a printing state where the thermal head is in contact with the platen drum, the ribbon moving position detecting means is brought close to the reflecting plate, and in a ribbon moving position detecting state where the thermal head is separated from the platen drum, In the ink ribbon position detection device configured to separate the ribbon movement position detection means from the reflection plate, the reflection plate is provided movably with respect to the support member, and in the movement position detection state of the ink ribbon, the reflection plate A plate is made to protrude from the support member and brought close to the ribbon movement position detection means, and in a printing state, as the thermal head comes into contact with the platen drum, the ribbon movement position detection means moves the reflection plate to the ribbon movement position detection means. An ink ribbon position detection device characterized in that the ink ribbon is retracted into a support member.