JP2021031271A - Film conveyance mechanism, indirect transfer system printer, and film conveying method - Google Patents

Abstract

To provide a film conveyance mechanism capable of easily correcting conveyance deviation at low cost.SOLUTION: In the film conveyance mechanism, two shafts 10a, 10b are erected on a substrate 10 provided at one side of a conveying path of a film 20, one shaft being erected upward and the other shaft being erected downward of the film conveying path; the substrate can be reciprocated in a vertical direction between a position where one shaft comes in contact with the film and where the other shaft comes in contact with the film; a lot of smoothly shaped ridge parts are formed on outer peripheral surfaces of the two shafts so that the ridge parts are inclined oppositely to each other; guide roller pairs 11, 12 interposing a conveying path from above and below are provided at an upstream side and a downstream side of the substrate; sensors 15, 16 for detecting conveyance deviation of the film are provided at both side edge parts in the vicinity of the substrate in a width direction of the film, and when the conveyance deviation is larger than a predetermined allowable width t, either of the two shafts which is inclined oppositely to a direction of the conveyance deviation is brought into contact with the film to correct the conveyance deviation.SELECTED DRAWING: Figure 1

Description

The present invention relates to a film transport mechanism for transporting an ink ribbon or an intermediate transfer film used in an indirect transfer printer, and more specifically, an indirect transfer printer capable of correcting a transport deviation of the ink ribbon or the intermediate transfer film. The present invention relates to a film transfer mechanism, an indirect transfer printer, and a film transfer method. In the present specification, the term "film" means an ink ribbon or an intermediate transfer film used in the above-mentioned indirect transfer printer, individually or collectively.

The indirect transfer printer is a printer in which the ink layer of the ink ribbon unwound from the winding body of the ink ribbon is once transferred to an intermediate transfer film using a thermal head, and then retransferred to the transferred body. In the indirect transfer method, even if the base material of the transfer target to which the image is finally provided is different, such as paper or plastic, printing is performed on the intermediate transfer film at the time of image formation, so that the printing target is constant. It has been put into practical use for a long time because it enables stable image formation.

In the image forming method using the indirect transfer method, each thermal transfer ink layer such as cyan, magenta, yellow, and black ink provided on the ink ribbon is superposed on a predetermined position of the intermediate transfer film and thermally transferred by a thermal head to form an image. However, at this time, the intermediate transfer film needs to reciprocate a predetermined position many times to transfer each ink without misalignment. In addition, it is necessary to prevent the positional deviation from occurring even during transfer onto the transfer target. For this reason, in the design and manufacture of indirect transfer printers, the film transfer mechanism that conveys ink ribbons and intermediate transfer films requires high precision, and as a result, it has become one of the causes of increased printer costs. ..

As a means for accurately transporting the film, as shown in FIG. 10, a method of providing a regular perforated portion 201 in the film 200 and transporting the film by a sprocket 202 has been used for transporting a photographic sensitive film. Was used from. Patent Document 1 and the like can be mentioned as an example of applying such a method to a heat-sensitive transfer printer.

However, from the viewpoint of speeding up the indirect transfer printer and improving the printing sensitivity, the base material used for the ink ribbon, the intermediate transfer film, etc. is required to be as thin as possible, and in reality, it is about several μm to several tens of μm. There is a need to. Therefore, it has been difficult to adopt a method in which a perforated portion is provided in the base material and the base material is conveyed by a sprocket because the base material is broken or wrinkled. For this reason, indirect transfer printers are usually not provided with a special mechanism for preventing transport deviation.

Japanese Unexamined Patent Publication No. 8-188307

The present invention is a film transfer mechanism, an indirect transfer printer, and a film transfer method that do not extremely require the design and assembly accuracy of the film transfer mechanism in the indirect transfer printer, and can easily correct the transfer deviation at a relatively low cost. The challenge is to provide.

In order to solve the above problems, one aspect of the present invention is
A film transport mechanism that transports film.
The substrate is provided on one side of the film transport path in a direction orthogonal to the film surface.
Two shafts extending in the width direction of the film are erected on the substrate, one on the upper side of the film transport path and the other on the lower side of the film transport path.
The substrate can reciprocate in the vertical direction between the position where the one shaft abuts on the film and the position where the other shaft abuts on the film.
The two shafts have a large number of smooth-shaped ridges inclined with respect to the film transport direction along the outer peripheral direction on at least the outer peripheral surface that comes into contact with the film, and the two shafts. Is formed so that the inclinations of are opposite to each other,
A pair of guide rollers that sandwich the transport path from above and below are provided on the upstream side and the downstream side of the substrate, respectively.
Sensors for detecting the transport deviation in the width direction of the film are provided on both side edges of the film in the vicinity of the substrate, and when the transport deviation becomes larger than a predetermined allowable width, the above 2 The film transport mechanism is characterized in that a shaft whose inclination is opposite to the direction of the transport deviation is brought into contact with the film to correct the transport deviation.

Two shafts on which a large number of smooth ridges having slopes in opposite directions are formed along the outer peripheral direction on a substrate provided on one side of the film transport path at right angles to the film surface are formed in the film transport path. When the transport deviation of the film, which is provided on the top and bottom and detected by the sensor, exceeds the predetermined allowable width, the substrate is moved in the vertical direction and the shaft whose ridge is tilted in the direction opposite to the transport shift direction is attached to the film. By abutting, the film transfer deviation can be corrected by the stress received from the inclined ridge portion, and the film transfer deviation can be corrected with a relatively simple structure.

Further, in the above film transport mechanism,
The ridge portion may be formed by fitting spring rollers wound in different winding directions to the two shafts. When providing ridges with inclinations in different directions on two shafts, it can be formed simply by fitting spring rollers with different winding directions, and a complicated process such as spirally cutting the outer peripheral surface of the shafts. It is possible to easily obtain shafts in which ridges are provided in different directions without requiring the above.

Further, in the above film transport mechanism,
The sensor may detect the transport deviation by detecting the alignment mark provided on the film. The misalignment of the film can be detected by reading the alignment mark provided on the film, and it is not necessary to use a film having a special mark or the like for detection.

Further, in the above film transport mechanism,
The interval d between the detection positions of the sensors may be d = W-2t, where W is the width of the film and t is the allowable width of the transport deviation. By setting the detection position of the sensor provided on both side edges of the film to a specific position, it is possible to detect whether or not it is within the allowable range of transport deviation with a general transmissive photo sensor, and the side by expensive laser light. There is no need to use a sensor with a long function.

Another aspect of the present invention is
An ink ribbon having at least one or more ink layers on a substrate and an intermediate transfer film having a removable transfer layer on the substrate are included, and the intermediate transfer film, the ink ribbon, or both of them. This is an indirect transfer printer, characterized in that any of the above film transport mechanisms is provided in the transport path of the above.

The third aspect of the present invention is
A film transport method for transporting a film, wherein the transport deviation in the width direction of the film is detected by a sensor provided on both side edges of the film in the width direction and detecting the transport deviation in the width direction of the film. A shaft in which a large number of smooth-shaped ridges are formed on the outer peripheral surface along the outer peripheral direction at an inclination with respect to the film transport direction when the transport deviation becomes larger than a predetermined allowable width. This film transport method is characterized in that the ridge portion of a shaft whose inclination direction of the ridge portion is opposite to the direction of the transport deviation is brought into contact with the film to correct the transport deviation.

According to the present invention, when an intermediate transfer film of an indirect transfer printer has a transfer deviation in the width direction exceeding an allowable value, a film transfer mechanism capable of automatically correcting the transfer deviation even with a relatively simple structure. Can be provided.

Further, according to another aspect of the present invention, it is possible to provide an indirect transfer type printer capable of satisfactorily correcting the transfer deviation of the film with a relatively simple structure.

Further, according to the third aspect of the present invention, when a transfer deviation occurs in the film, a large number of smooth-shaped ridges are formed on the outer peripheral surface along the outer peripheral direction with an inclination with respect to the film transfer direction. It is possible to provide a film transport method capable of easily correcting the transport deviation by abutting the ridge portion of the shaft.

It is a schematic external view of the film transport mechanism of this invention in a state where a spring roller shaft does not come into contact with a film. It is a schematic external view of the film transport mechanism in a state where one spring roller shaft is in contact with a film. It is a schematic external view of the film transport mechanism in a state where the other spring roller shaft is in contact with the film. It is a schematic diagram of the example of the reciprocating movement mechanism of a spring roller shaft. It is explanatory drawing of the correction action of the transport deviation by a spring roller shaft. It is explanatory drawing of the installation position of the sensor which detects the transport deviation. It is explanatory drawing of another example of the sensor which detects a transport deviation. It is a schematic block diagram of the indirect transfer type printer of this invention. It is sectional drawing of the shaft which ridge part was formed on the outer peripheral surface. It is a schematic diagram of the mechanism which conveys a film by a sprocket.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not construed as being limited to the following embodiments.

FIG. 1 is a schematic external view of an embodiment of the film transport mechanism of the present invention. 1 (a) is a side view, and FIG. 1 (b) is a plan view seen from above of FIG. 1 (a). The same relationship is obtained in FIGS. 2 and 3, and this is an example in which the film transfer mechanism 1 is provided in the transfer path of the intermediate transfer film 20 used in the indirect transfer printer. In the film transfer mechanism 1, in the front stage of the take-up shaft 21 of the intermediate transfer film 20, the substrate 10 is provided on one side of the transfer path of the intermediate transfer film 20 in a direction orthogonal to the intermediate transfer film surface, and the substrate 10 is provided with. The spring roller shafts 10a and 10b in which the spring rollers are fitted to the shafts are erected in a direction extending in the width direction of the intermediate transfer film 20. Further, guide roller pairs 11 and 12 that sandwich the transport path from above and below are provided on the upstream side and the downstream side of the substrate 10, respectively.

The spring roller shaft 10a is erected above the transfer path of the intermediate transfer film 20, the spring roller shaft 10b is erected below the transfer path of the intermediate transfer film 20, and the spring roller shaft 10a of the substrate 10 is the intermediate transfer film 20. It is possible to reciprocate in the vertical direction together with the spring roller shafts 10a and 10b between the position where the spring roller shaft 10b abuts from above and the position where the spring roller shaft 10b abuts on the intermediate transfer film 20 from below. However, at the reference position shown in FIG. 1, none of the spring roller shafts 10a and 10b is in contact with the intermediate transfer film 20. In FIGS. 2 and 3, for the sake of clarity of explanation, the inclination direction of the springs of the spring roller shafts 10a and 10b shows the portion where the spring roller shaft is in contact with the film transparently.

As shown in the cross-sectional view of the spring roller shafts 10a and 10b in FIG. 9A, a spring roller 14 in which a wire rod is spirally wound is fitted on a shaft 13 serving as a central axis, and a large number of ridges 24 are provided. Is formed, and by reversing the winding directions of the spirals, it can be assumed that the inclinations of the spirals are opposite to each other. Next, the operation when the spring roller shafts 10a and 10b are brought into contact with the intermediate transfer film 20 will be described.

FIG. 5A is a view focusing on a part of the spiral wire rod of the spring roller, and is a wire rod 30 which is a spiral wire inclined to the right in the film transport direction. The wire rod 30 is in contact with the intermediate transfer film 20 (not shown here) in a minute region 31, and the intermediate transfer film 20 is displaced in the direction of inclination of the wire rod 30 as shown by an arrow 32 due to frictional resistance with the intermediate transfer film 20. Acts like. When the inclination of the wire rod 30 is opposite as shown in FIG. 5B, the action is opposite, and the action of shifting the intermediate transfer film 20 in the opposite direction occurs. As described above, by bringing the spring roller shafts 10a and 10b into contact with the intermediate transfer film 20, the action of moving the intermediate transfer film 20 in the same direction as the inclination of the spiral of the spring roller can be generated.

In addition to the shaft fitted with the spring roller, for example, the outer peripheral surface of the shaft may be spirally cut to provide a semi-cylindrical ridge 24 as illustrated in FIG. 9B, or the shaft may be provided in a spiral shape. As illustrated in 9 (c), a large number of inclined semi-cylindrical ridges 24 may be provided side by side on a part of the outer peripheral surface of the shaft, and the same effect can be produced.

Further, in FIG. 1, photosensors 15 and 16 for detecting the transfer deviation of the intermediate transfer film 20 are provided on both side edges of the intermediate transfer film 20 in the width direction in the vicinity of the substrate 10. The photosensors 15 and 16 detect the transfer deviation by detecting the alignment mark 22 indicating the reference position when printing an image on the intermediate transfer film 20.

The black dots 17 provided on the photosensors 15 and 16 clearly indicate the position of the optical axis where the detection is actually performed, that is, the detection position 17. As shown in FIG. 1B, the positions where the photosensors 15 and 16 are provided are both side edges of the intermediate transfer film 20, but it is preferable that the distance between them is as follows. That is, when the width of the intermediate transfer film 20 is W and the allowable width of the transfer deviation is t, the distance d between the actual detection positions of the photosensors 15 and 16 is set to d = W-2t.

FIG. 6 is a diagram illustrating a state of detection of transport deviation when the photosensors 15 and 16 are provided at the above positions. FIG. 6A shows a state in which there is no transfer deviation, and the detection lights 18 and 19 of the photo sensors 15 and 16 can be detected by being shielded by the alignment mark 22 provided on the intermediate transfer film 20. It is possible, and it is judged that the transport deviation is within the permissible range.

On the other hand, when the intermediate transfer film 20 exceeds the allowable width t and shifts to the right side of the figure as shown in FIG. 6B, the detection light 18 is not shielded by one photo sensor 15 and the intermediate transfer film 20 cannot be detected. Therefore, it can be judged as a transport deviation exceeding the permissible range.

Similarly, as shown in FIG. 6C, when the transfer deviation occurs to the left beyond the allowable width t, the detection light 19 is not shielded by the other photosensor 16 and the intermediate transfer film 20 cannot be detected. It can be judged as a transport deviation exceeding the permissible range. As described above, even with the general-purpose inexpensive photosensors 15 and 16, if the interval is set to an appropriate value, it is possible to detect the transfer deviation when the allowable width t is exceeded. The detection light of the photo sensor is not a mathematical straight line but has a thickness, and there are variations in the sensitivity of the photo sensor. Therefore, when actually installing the photo sensor, some position adjustment is required, and the interval d The values may not be exactly as per the above equations, but they are also within the scope of the present invention.

The sensor for detecting the transport deviation is not limited to the photo sensor as described above. For example, as shown in FIG. 7, the width of the light emitting portion that emits the band-shaped detection light 41 and the width of the band-shaped detection light 41 A sensor 40 in combination with a light receiving portion that can be detected can also be used. As shown in FIG. 7, the sensor 40 is provided on both side edges in the same manner as the photo sensors 15 and 16, and the band-shaped detection is performed by the alignment mark 22 of the intermediate transfer film 20. The transport deviation can be detected by detecting the width at which the light 41 is blocked.

With this sensor 40, the amount of transport deviation can be numerically obtained, and since it is not determined whether or not to shield as in the case of using the photo sensors 15 and 16, the interval to be provided is not so limited and can be detected. It may be provided as appropriate. Alternatively, the same function can be obtained simply by providing the film on one side edge. However, in general, a sensor having such a width measuring function is more expensive than a general-purpose photo sensor, which may lead to an increase in cost.

Returning to FIG. 1, the substrate 10 has a spring roller shaft 10a between a position where the spring roller shaft 10a abuts on the intermediate transfer film 20 from above and a position where the spring roller shaft 10b abuts on the intermediate transfer film 20 from below. It is connected to a drive mechanism for reciprocating in the vertical direction together with 10b. The drive mechanism is not particularly limited as long as it can be linearly reciprocated, but here, in FIG. 4, the ball screw 107 is driven by the motor 108 and rotated in the forward and reverse directions to rotate the substrate 10 into a spring roller shaft. A mechanism for moving the 10a and 10b in the vertical direction of FIG. 1 will be illustrated.

As shown in FIG. 1, the ball screw 107 and the motor 108 are provided on the back surface side of the substrate 10, that is, on the side opposite to the intermediate transfer film 20, and are connected to the substrate 10. As the drive mechanism for reciprocating movement, other known linear drive mechanisms such as a rack and pinion mechanism and a solenoid mechanism can be appropriately selected and applied according to the required specifications.

When there is no transfer deviation of the intermediate transfer film 20, the transfer mechanism 1 is in a position where none of the spring roller shafts 10a and 10b abuts on the intermediate transfer film 20 as shown in FIG. 1, and does not affect the transfer. Become. The location of the film transport mechanism 1 in the transport path is not particularly limited, but the front stage of the take-up shaft 21 is suitable because transport deviations are likely to accumulate and transfer deviations are easily detected.

FIG. 2 shows an example of a mode in which the intermediate transfer film 20 causes a transport deviation exceeding the allowable width t, and is a state in which the intermediate transfer film 20 is displaced upward in FIG. 2 (b). At this time, the detection position 17 of the photo sensor 16 is a position deviated from the intermediate transfer film 20, and the alignment mark 22 cannot be detected. Then, as shown in FIG. 2A, the substrate 10 is moved downward, and the spring roller shaft 10a whose inclination direction of the spring roller is opposite to the direction of the transfer deviation is brought into contact with the intermediate transfer film 20. When the intermediate transfer film 20 is conveyed in this state, due to the effect of the spring roller of the spring roller shaft 10a, the intermediate transfer film 20 gradually moves in the same direction as the inclination of the spiral of the spring roller, and in FIG. 2B, in the direction of the white arrow (downward). shift. When the transport deviation is corrected to be equal to or less than the allowable width t, the substrate 10 is moved upward, the contact of the spring roller shaft 10a is released, and the substrate 10 returns to the original position.

At this time, since the guide rollers 11 and 12 that sandwich the transport path from above and below are provided on the upstream side and the downstream side of the substrate 10, the substrate 10 moves downward and the intermediate transfer film 20 is a spring roller shaft. When the intermediate transfer film 20 comes into contact with the guide rollers 11 and 12, the intermediate transfer film 20 can also come into contact with the guide rollers 11 and 12, so that the angle around the spring roller 10a, the winding pressure, and the like can be kept constant. It is possible to make the effect of correcting the transport deviation of the above more stable.

FIG. 3 shows another example of the mode in which the intermediate transfer film 20 causes a transport deviation exceeding the allowable width t, and is a state in which the intermediate transfer film 20 is displaced downward in FIG. 3 (b). At this time, the detection position 17 of the photo sensor 15 is a position deviated from the intermediate transfer film 20, and the alignment mark 22 cannot be detected. Then, as shown in FIG. 3A, the substrate 10 is moved upward, and the spring roller shaft 10b whose inclination direction of the spring roller is opposite to the direction of the transfer deviation is brought into contact with the intermediate transfer film 20. When the intermediate transfer film 20 is conveyed in this state, the intermediate transfer film 20 gradually moves in the same direction as the inclination of the spiral of the spring roller due to the effect of the spring roller of the spring roller shaft 10b, and in the direction of the white arrow (upward) in FIG. 3 (b). shift. When the transport deviation is corrected to be equal to or less than the allowable width t, the substrate 10 is moved downward, the contact of the spring roller shaft 10b is released, and the substrate 10 returns to the original position.

Even in this case, the guide roller pairs 11 and 12 have the same effect as in the case of FIG. 2, and the effect of correcting the transport deviation of the spring roller 10b can be stabilized. As described above, the transport mechanism 1 of the present invention corrects the transport deviation.

FIG. 8 is a schematic configuration diagram of an indirect transfer printer 100 provided with the transfer mechanism of the present invention in the transfer path of the intermediate transfer film 20. After the primary transfer image 103 is formed on the intermediate transfer film 20 by the thermal head 101 and the ink ribbon 102, the intermediate transfer film 20 is conveyed and thermal pressure transfer is performed on the transferred body 104 by the heat roller 105. The transport mechanism of the present invention includes a substrate 10 on which a spring roller shaft is erected in front of the take-up shaft 106 of the intermediate transfer film 20, and guide roller pairs 11 and 12 provided on the upstream and downstream sides thereof, and a photo. It is provided by providing a sensor 15 and a photo sensor 16 (not shown). According to the transport mechanism of the present invention, even if the intermediate transfer film has a transport misalignment, it can be easily corrected.

All of the examples described above are examples in which the transfer mechanism 1 is provided in the transfer path of the intermediate transfer film, but the present invention is not limited to this, and the transfer mechanism 1 may be provided in the transfer path of the ink ribbon. Needless to say, the effect of correcting the transport deviation can be obtained. It can also be provided both in the transport path of the intermediate transfer film and in the transport path of the ink ribbon.

1 ... Transfer mechanism 10 ... Substrate 10a, 10b ... Spring roller shafts 11, 12 ... Guide roller pair 13 ... Shaft 14 ... Spring rollers 15, 16 ... Photosensor 17 ...・ Detection position (black dot)
18, 19 ... Detection light 20 ... Intermediate transfer film 21 ... Winding shaft 22 ... Alignment mark 24 ... Ridge 30 ... Wire rod 31 ... Small area 40 ... Sensor 41: Strip-shaped detection light 100: Indirect transfer printer 101: Thermal head 102: Ink ribbon 103: Primary transfer image 104: Transferee 105: Heat roller 106 ... Winding shaft 107 ... Ball screw 108 ... Motor

Claims (6)

A film transport mechanism that transports film.
The substrate is provided on one side of the film transport path in a direction orthogonal to the film surface.
Two shafts extending in the width direction of the film are erected on the substrate, one on the upper side of the film transport path and the other on the lower side of the film transport path.
The substrate can reciprocate in the vertical direction between the position where the one shaft abuts on the film and the position where the other shaft abuts on the film.
The two shafts have a large number of smooth-shaped ridges inclined with respect to the film transport direction along the outer peripheral direction on at least the outer peripheral surface that comes into contact with the film, and the two shafts. Is formed so that the inclinations of are opposite to each other,
A pair of guide rollers that sandwich the transport path from above and below are provided on the upstream side and the downstream side of the substrate, respectively.
Sensors for detecting the transport deviation in the width direction of the film are provided on both side edges of the film in the vicinity of the substrate, and when the transport deviation becomes larger than a predetermined allowable width, the above 2 A film transport mechanism characterized in that, among the shafts of a book, a shaft whose inclination is opposite to the direction of the transport deviation is brought into contact with the film to correct the transport deviation. The film transport mechanism according to claim 1, wherein the ridge portion is formed by fitting spring rollers wound in different winding directions to the two shafts. The film transport mechanism according to claim 1 or 2, wherein the sensor detects a transport deviation by detecting an alignment mark provided on the film. Any one of claims 1 to 3, wherein the interval d between the detection positions of the sensors is d = W-2t, where W is the width of the film and t is the allowable width of the transport deviation. The film transport mechanism described in 1. An ink ribbon having at least one or more ink layers on a substrate and an intermediate transfer film having a removable transfer layer on the substrate are included, and the intermediate transfer film, the ink ribbon, or both of them. The indirect transfer type printer, characterized in that the film transport mechanism according to any one of claims 1 to 4 is provided in the transport path of the above. A film transport method for transporting a film, wherein the transport deviation in the width direction of the film is detected by a sensor provided on both side edges of the film in the width direction and detecting the transport deviation in the width direction of the film. A shaft in which a large number of smooth-shaped ridges are formed on the outer peripheral surface along the outer peripheral direction at an inclination with respect to the film transport direction when the transport deviation becomes larger than a predetermined allowable width. A film transport method characterized in that the ridge portion of a shaft whose inclination direction of the ridge portion is opposite to the direction of the transport deviation is brought into contact with the film to correct the transport deviation.