Patent Application
20210300012
Contents disclosed in the specification, drawings and claims of the following Japanese Patent Application are all incorporated herein by reference.
Japanese Patent Application No. 2018-138450 (filed on Jul. 24, 2018)
This invention relates to a printing system and a printing method for applying a printing process to articles having a three-dimensional shape such as daily commodities including bottles and in-vehicle components.
Intaglio printing has a property of being able to print a pattern incised in an intaglio with higher reproducibility than printing methods such as screen printing and ink-jet printing. Utilizing this property, an attempt has been made to form an electrode pattern in a device such as an electronic circuit board or a touch panel board by intaglio printing (patent literature 1). Further, a printing device described in the above patent literature 1 performs printing on one principal surface, i.e. a flat surface, of a board, but a technique for printing on a curved surface has also been proposed (see patent literature 2).
[Patent literature 1] JP 2018-27659A
[Patent literature 1] JP 2017-132052A
Articles handled by these printing devices are flat plate works having a flat non-printing surface. Thus, a single article can be conveyed to a position for intaglio printing (corresponding to an “alignment position” of the invention) while being kept in a posture suitable for printing by a conventional conveyance technique such as a conveyor and a printing process can be performed by a printing unit. However, to perform the printing process for articles having a three-dimensional shape such as daily commodities including bottles and in-vehicle components, it is necessary to provide a holding mechanism conforming to the shape of the articles at the alignment position and mount the article in the holding mechanism immediately before printing on the article is performed.
Since such article mounting is associated with a complicated operation, a mounting tact necessarily becomes long. This is one of main factors reducing a throughput of the printing process for printing on articles having a three-dimensional shape.
This invention was developed in view of the above problem and aims to provide a printing system and a printing method capable of printing on articles in a short throughput time also when the articles are those having a three-dimensional shape such as bottles and in-vehicle components.
One aspect of the invention is a printing system, comprising: a circulating conveyor device including a holder conveying mechanism for conveying a holder configured such that an article is removably mountable thereinto, the circulating conveyor device circulatingly conveying the holder along a circulation path having a mounting position where the article is mounted into the holder and a transfer position different from the mounting position; a printing device arranged away from the circulating conveyor device while facing the transfer position, the printing device printing on the article positioned at an alignment position; and a reciprocally moving device that positions the article at the alignment position by moving the holder having the article mounted therein to the printing device and returning the holder to the transfer position after printing on the article by the printing device; wherein, when the holder having the article mounted therein is a first holder and the holder having the article not mounted therein is a second holder, the circulating conveyor device stops the second holder at the mounting position while an article different from the article mounted in the first holder is mounted into the second holder in parallel with at least one of a forward movement of the first holder to the alignment position by the reciprocally moving device, printing on the article by the printing device and a return movement of the first holder to the transfer position by the reciprocally moving device.
Other aspect of the invention is a printing method for printing on an article by a printing device, comprising: a transfer conveyance step of conveying a first holder having the article before printing mounted therein to a transfer position facing the printing device; a forward movement step of moving the first holder from the transfer position to the printing device and positioning the article at an alignment position; a printing step of printing on the article with the article positioned at the alignment position; a return movement step of returning the first holder having the printed article mounted therein from the printing device to the transfer position; and an article mounting step of mounting an article different from the article mounted in the first holder into a second holder different from the first holder at a mounting position separated from the printing device and the transfer position in parallel with at least one of the forward movement step, the printing step and the return movement step.
In the invention thus configured, the article is conveyed to the printing device via the transfer position while being kept mounted in the first holder, and returned to the transfer position together with the first holder after printing with the article positioned at the alignment position of the printing device. On the other hand, the article to be printed after the above article is mounted into the second holder at the mounting position separated from the printing device and the transfer position in parallel with at least a part of such a print-related process (forward movement, printing and return movement). That is, a mounting process of the article into the holder and the print-related process are performed partially or entirely in parallel.
As described above, since the article is mounted into the holder in parallel with the conveyance of the article kept mounted in the holder to the printing device and printing on the article, printing on the article can be performed in a short throughput time also when the article is the one having a three-dimensional shape such as a bottom or an in-vehicle component.
All of a plurality of constituent elements of each aspect of the invention described above are not essential and some of the plurality of constituent elements can be changed, deleted or replaced by new other constituent elements or limitation contents can be partially deleted as appropriate to solve some or all of the problems described above or achieve some or all of effects described in this specification.??Further, some or all of technical features included in one aspect of the invention described above can be combined with some or all of technical features included in another aspect of the invention described above into one independent aspect of the invention to solve some or all of the problems described above or achieve some or all of effects described in this specification.
The printing system 1 is provided with a circulating conveyor device 3. The circulating conveyor device 3 includes a holder conveying mechanism 31 for conveying the holder 2 along a circulation path PT having a container exchange position P1, a transfer position P2 and a post-processing position P3. The holder conveying mechanism 31 operates in response to a command from a drive controller 44 of a control device 4 for controlling the entire printing system 1 and circulatingly moves the holder 2 in an order of the container exchange position P1, the transfer position P2 and the post-processing position P3. A conveyor conveying mechanism for simultaneously conveying the holder 2 from the container exchange position P1 to the transfer position P2 (hereinafter, referred to as “transfer conveyance M1”), moving the holder 2 from the transfer position P2 to the post-processing position P3 (hereinafter, referred to as “post-processing conveyance M2”) and moving the holder 2 from the post-processing position P3 to the container exchange position P1 (hereinafter, referred as “exchange conveyance M3”) or an independent conveying mechanism for performing the transfer conveyance M1, the post-processing conveyance M2 and the exchange conveyance M3 independently of each other may be used as the holder conveying mechanism 31. Note that the independent conveying mechanism is used in this embodiment.
A sensor is arranged at each of the container exchange position P1, the transfer position P2 and the post-processing position P3. The sensors detect the holders 2 located at the container exchange position P1, the transfer position P2 and the post-processing position P3 and give signals indicating those to an input/output unit 45 of the control device 4. An arithmetic processor 41 of the control device 4 obtains the positions of the holders 2 configured as described next and the containers B mounted in the holders 2 based on these signals. Note that, out of the above sensors, the one provided at the transfer position P2 contributes to controlling a reciprocal movement of the holder 2 together with a sensor provided at an alignment position as described in detail later.
As shown in
The bottom holding part 24 includes a rotary body 241 provided rotatably with respect to the column part 22 and a spring member 242 mounted on the rotary body 241. One end part of the spring member 242 is a fixed end fixed to the rotary body 241, and the other end part is a free end extending toward the column part 23. On the other hand, the lid closing holding part 25 includes a coupling member 251 removably attachable to a lid closing part Bc while being supported rotatably with respect to the column part 23. Thus, as shown in
In the holder 2 configured as just described, the container B can be mounted and removed by an operator when being positioned at the container exchange position P1. That is, the container B can be mounted into the holder 2 by coupling the lid closing part Bc of the container B to the coupling member 251 of the lid closing holding part 25 after the container B is arranged in a horizontal state between the column parts 22, 23 while the bottom part Bb of the container B before printing is pressed against the spring member 242. Further, by moving the printed container B in the holder 2 toward the column part 22 against the biasing force of the spring member 242 and releasing the coupling of the lid closing part Bc by the coupling member 251 after printing, the container B can be removed from the holder 2. Note that a mounting/removing method of the container B into and from the holder 2 is not limited to this and a mounting/removing method corresponding to a holding function of the container B in the holder 2 can be employed.
The holder 2 has a rotating function of rotating the container B about the axis of rotation AX during intaglio printing by a printing device to be described later besides the holding function of merely rotatably holding the container B in a horizontal state. This rotating function is performed by a container rotator 26. This container rotator 26 includes a rotating motor 261 and a rotation transmitting mechanism 262 for transmitting a rotational force of the motor 261 to the lid closing part Bc of the container B. If the motor 261 operates in response to a rotation command from the drive controller 44 of the control device 4, the container B before printing rotates about the axis of rotation AX while being held in a horizontal state by being sandwiched by the bottom holding part 24 and the lid closing holding part 25.
The holder 2 having the container B before printing mounted thereinto by the operator is conveyed along a path PT1 from the container exchange position P1 toward the transfer position P2, out of the circulation path PT, by the holder conveying mechanism 31. That is, the transfer conveyance M1 (see
The alignment unit 51 is provided to make a posture of the container B mounted in the holder 2 with respect to the printing unit 52, i.e. a relative positional relationship of the container B and the printing unit 52, suitable for printing. In this embodiment, the holder 2 is relatively moved by a position adjuster (not shown) based on an alignment image obtained by imaging a part of the container B by an unillustrated camera to correct the posture of the container B. A conventionally known means can be used for posture correction. For example, a plurality of images are obtained by imaging a plurality of characteristic parts, alignment marks or the like included in the container B, and those images are processed by an image processor 43 of the control device 4. Then, based on image data obtained thereby, the arithmetic processor 41 three-dimensionally moves the holder 2 at the alignment position Pa to relatively move the container B with respect to the printing unit 52 and correct the posture of the container B with respect to the printing unit 52 to a reference state. The container B is printed by the printing unit 52 after this posture correction.
The printing unit 52 performs basically the same printing method as in patent literature 1, i.e. intaglio printing. That is, the printing unit 52 causes a transfer roller to receive a pattern of an ultraviolet curable material corresponding to an intaglio by pressing the intaglio filled with the ultraviolet curable material against the transfer roller. Further, the pattern on the transfer roller is transferred to the trunk part Ba of the container B while the container B corrected in the reference printing posture is rotated about the axis of rotation AX (see
As just described, in this embodiment, the printing device 5 is provided separately from the circulating conveyor device 3 and the container B can be printed independently of a circulating conveying movement of circulatingly conveying the container B together with the holder 2 by the circulating conveyor device 3. Further, a reciprocally moving device 6 is provided in the printing system 1 to correspond to the separate arrangement of the circulating conveyor device 3 and the printing device 5.
The reciprocally moving device 6 has a shuttle configuration of reciprocally moving a base (not shown), on which the holder 2 having the container B mounted therein can be placed, between the transfer position P2 and the alignment position Pa. A mechanism configured by combining a linear guide and a motor, a mechanism constituted by a linear actuator such as an air cylinder or the like can be, for example, used as a specific configuration for moving the base.
In this embodiment, sensors 71, 72 for detecting the base are respectively provided at the transfer position P2 and the alignment position Pa, and the control device 4 controls the reciprocally moving device 6 based on detection signals from the respective sensors 71, 72. In this way, the container B can be positioned at the alignment position Pa by moving the holder 2 having the container B mounted therein to the printing device 5, and the holder 2 can be returned to the transfer position P2 after printing by the printing device 5.
The holder 2 returned to the transfer position P2 in this way is conveyed along a path PT2 from the transfer position P2 to the post-processing position P3, out of the circulation path PT, by the holder conveying mechanism 31. That is, the post-processing conveyance M2 (see
The control device 4 is provided with a storage 42 for storing a print program for performing a printing operation, various pieces of data and the like, besides the above arithmetic processor 41, image processor 43, drive controller 44 and input/output unit 45. The arithmetic processor 41 reads out the print program from the storage 42, and performs a printing process to be described in detail next by controlling each component of the system in accordance with the print program.
In an initial state (timing T1 of
If it is confirmed that the operator has manually mounted the first container B1 before printing into the holder 2 positioned at the container exchange position P1 (timing T2), the holder conveying mechanism 31 conveys the holder 2 having the container B1 mounted therein along the path PT1 (transfer conveyance M1). Further, in synchronization with this, the holder conveying mechanism 31 conveys the empty holders 2 located at the transfer position P2 and the post-processing position P3 respectively along the paths PT2, PT3. That is, the post-processing conveyance M2 and the exchange conveyance M3 are performed. In this way, the first container B1 is located at the transfer position P2 and the empty holders 2 are located at the container exchange position P1 and the post-processing position P3 (timing T3).
If the holder 2 having the container B1 before printing mounted therein is conveyed to the transfer position P2, this holder 2 is moved to the alignment position Pa by the reciprocally moving device 6 (forward movement). At this alignment position Pa, the position of the holder 2 is moved by the alignment unit 51 to correct the posture of the container B1 mounted in this holder 2 with respect to the printing unit 52. After this posture correction, a pattern of the ultraviolet curable material is printed on the trunk part Ba of the container B1 kept mounted in the holder 2 by the printing unit 52, and the printed pattern is further temporarily cured. If printing and temporary curing on the container B1 are completed in this way, a return movement of the holder 2 is carried out by the reciprocally moving device 6. That is, the holder 2 is returned to the transfer position P2 by the reciprocally moving device 6 while holding the container B1 (timing T4).
In parallel with the reciprocal moving operation of the holder 2 to and from the alignment position Pa, the printing operation, the temporary curing operation and the return moving operation of the holder 2 to the transfer position P2 performed in this way, the operator manually mounts the second container B2 before printing into the holder 2 stopped at the container exchange position P1. Note that although the container B is manually exchanged using an entire time from timing T3 to timing T4 in this embodiment, the container B2 may be mounted into the holder 2 in parallel with at least some of the forward moving operation, the printing operation, the temporary curing operation and the return moving operation. Further, a series of operations including a forward movement, printing, temporary curing and a return movement is referred to as a “print-related process” below for the convenience of description.
If the holder 2 having the container B1 subjected to printing and temporary curing mounted therein returns to the transfer position P2, the holders 2 located at the container exchange position P1, the transfer position P2 and the post-processing position P3 are respectively conveyed to the transfer position P2, the post-processing position P3 and the container exchange position P1. That is, as shown in
Further, if the holder 2 having the container B2 subjected to printing and temporary curing mounted therein returns to the transfer position P2, the holders 2 located at the container exchange position P1, the transfer position P2 and the post-processing position P3 are respectively conveyed to the transfer position P2, the post-processing position P3 and the container exchange position P1. That is, as shown in
Note that, thereafter, every time the holders 2 are intermittently conveyed along the circulation path PT, the container exchanging operation of the Nth (where N is a natural number equal to or greater than 2) printed container BN and the (N+3)th container B(N+3) before printing at the container exchange position P1, the print-related process for the (N+2)th container B(N+2) and the (N+1)th main curing process are performed in parallel.
As described above, according to this embodiment, the container B having a three-dimensional shape is mounted into the holder 2, and the pattern is printed on the trunk part Ba of the container B kept in the mounted state by the printing device 5. Thus, the pattern can be satisfactorily printed by the printing unit 52 regardless of the shape of the container B. Further, since the posture of the container B with respect to the printing unit 52 is corrected by the alignment unit 51 before printing by the printing unit 52 in the printing device 5, printing can be constantly performed in a proper printing posture and printing accuracy can be enhanced. Particularly, in a printing system in which a plurality of printing devices 5 are installed in parallel and a plurality of patterns are superimposed on the same container B as described later, the misalignment of the patterns can be suppressed and a high-quality image can be printed on the container B having a three-dimensional shape.
Further, a certain period of time is necessary for an operation of manually mounting the container B having a three-dimensional shape into the holder 2 and manually removing the container B from the holder 2. This may become one of factors reducing throughput. However, in this embodiment, the above manual operation is performed in parallel with at least a part of the print-related process (forward movement, printing, temporary curing and return movement). That is, the mounting operation of the container B into the holder 2 and the removing operation of the container B from the holder 2 are performed partially or entirely in parallel with the print-related process and the main curing process (post-process). As a result, printing on the container B can be performed in a short throughput time.
In the above embodiment, the container B corresponds to an example of an “article” of the invention. Further, the holder conveying mechanism 31 corresponds to an example of a “conveying mechanism” of the invention. Further, the container exchange position P1 corresponds to an example of a “mounting position” of the invention. Further, for example, from timing T3 to timing T4, the holder 2 having the container B1 mounted therein corresponds to an example of a “first holder” of the invention, the empty holder 2 conveyed from the post-processing position P3 to the container exchange position P1 corresponds to an example of a “second holder” of the invention and the container B2 mounted in the empty holder 2 corresponds to an example of an “article different from the article mounted in the first holder” of the invention. Further, a step of conveying the holder 2 having the container B before printing mounted therein to the transfer position P2 along the path PT1 corresponds to an example of a “transfer conveyance step” of the invention, the forward movement, the printing and the return movement respectively correspond to examples of a “a forward movement step”, a “printing step” and a “return movement step” of the invention, and the mounting of the container B at the container exchange position P1 corresponds to an example of an “article mounting step” of the invention.
Note that the invention is not limited to the above embodiment and various changes other than the aforementioned ones can be made without departing from the scope of the invention. For example, although the invention is applied to the printing system 1 provided with only one printing device 5 in the above embodiment, the invention can be applied also to a printing system 1, for example, provided with two printing devices 5 as shown in
Further, in the above embodiment, as shown in
Further, although the post-processing device 7 is provided in the above embodiment, it is not necessary to install the post-processing device 7, for example, if the pattern can be satisfactorily fixed to the container B by ultraviolet irradiation in the printing unit 52. That is, the post-processing device 7 is not an essential component, but an arbitrary component in the invention.
Further, although the position adjuster is provided in the printing device 5 to adjust the posture of the container B with respect to the printing unit 52 in the above embodiment, a position adjuster may be provided in the reciprocally moving device 6. That is, the posture of the container B may be adjusted during or immediately after the forward movement of the holder 2 having the container B before printing mounted therein to the alignment position Pa by the reciprocally moving device 6, and printing may be performed with the holder 2 held by the reciprocally moving device 6.
Further, although the container exchange position P1 not only functions as the “mounting position” of the invention, but also the printed container B is removed from the holder 2 at the container exchange position P1 in the above embodiment, the container B may be removed on a side closer to the post-processing device 7 than the container exchange position P1.
Further, although the mounting/removing operation of the container B into/from the holder 2 is performed by the operator in the above embodiment, the mounting operation and the removing operation may be performed by a robot.
Further, although the pattern of the ultraviolet curable material is printed on the container B as the “article” of the invention in the above embodiment, the invention can be applied also to a printing technique for printing a pattern on articles having a three-dimensional shape such as in-vehicle components other than containers.
Furthermore, although the invention is applied to the printing system 1 provided with the printing device 5 for performing intaglio printing in the above embodiment, the invention can be applied also to a printing technique provided with a printing device for printing on articles having a three-dimensional shape such as containers B and in-vehicle components by another method.
Although the invention has been described by way of the specific embodiments above, this description is not intended to be interpreted in a limited sense. By referring to the description of the invention, various modifications of the disclosed embodiments will become apparent to a person skilled in this art similarly to other embodiments of the invention. Hence, appended claims are thought to include these modifications and embodiments without departing from the true scope of the invention.
The invention is generally applicable to printing techniques for applying a printing process to articles having a three-dimensional shape such as daily commodities including bottles and in-vehicle components.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2018-138450 | Jul 2018 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2019/019089 | 5/14/2019 | WO | 00 |
