JP2018171790A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printer which can detect an end part of a printing medium, enables easy manufacturing and adjustment, and achieves low costs.SOLUTION: Inkjet heads 19a to 19d and a sensor stand 37 are provided at a side plate 31, and a sensor positioning member 39 is attached to the sensor stand 37. A sensor unit 40 is positioned and attached to the sensor positioning member 39. A sensor stay 42 is attached to the sensor unit 40. A side end detection part 29 includes a light projection part 29a and a light reception part 29b. The light projection part 29a is attached to a support part 43 detachably attached to the sensor stay 42 through a positioning mechanism 44. The light reception part 29b is attached to a sensor attachment plate 41 through the sensor stay 42.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a printing apparatus that performs printing on a print medium while detecting the position of a side edge of the print medium.

  2. Description of the Related Art Conventionally, for example, in an inkjet printing apparatus, an ink droplet is ejected from an inkjet head and an image is printed on the print medium while conveying a print medium such as continuous paper. For example, when transporting a long print medium such as continuous paper, the side edge position of the continuous paper may fluctuate in a direction orthogonal to the transport direction. In such a state, there arises a disadvantage that the printing start position from the side edge of the continuous paper fluctuates. In view of this, a printing apparatus has been proposed in which a mechanism for detecting a side edge position of a print medium is provided and printing is performed by performing appropriate control while detecting the side edge position (see, for example, Patent Document 1).

JP 2013-116635 A

In the technique described in Patent Document 1, the conveyed print medium is imaged with a CCD camera, and the edge of the print medium is detected by analyzing the image. Therefore, the mechanism for edge detection is expensive, and complicated image analysis is required for detection, and the whole is large and expensive.
It is also conceivable to use an optical sensor having a light projecting and light receiving mechanism for detecting such an end. Although such a mechanism is relatively inexpensive, it is necessary to arrange the light projecting element and the light receiving element at an appropriate position with an appropriate distance between them, and in an appropriate direction. Adjustment and maintenance during operation took time, and the work was troublesome. In addition, if a unit in which the light projecting element and the light receiving element are integrally fixed is prepared and the unit is attached to the printing apparatus, the problem of adjustment between the light projecting element and the light receiving element is reduced. Such a unit is placed and fixed at an appropriate position for detecting the end of the print medium in a narrow printing apparatus in which a large number of parts such as a print head and a print medium transport mechanism are arranged. This is also accompanied by difficulties, and the manufacturing work has not been easy.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a printing apparatus that can detect the edge of a print medium and that is easy to manufacture and adjust and that is low-cost. .

  In order to achieve such an object, the present invention has the following configuration.

  That is, the invention described in claim 1 is a printing apparatus that conveys a print medium and performs printing while detecting the position of the end of the print medium, and is equipped with a conveyance mechanism that conveys the print medium. A base; a printing unit that performs printing on the print medium conveyed by the conveyance mechanism; a detection unit that is disposed along the conveyance mechanism and detects a side edge position of the print medium; and the detection unit An attachment mechanism for attaching the first detection unit to the base, the detection unit includes a first detection unit and a second detection unit paired with the first detection unit, and the attachment mechanism is provided on the base. An attachment base, a support attached to the attachment support, and a support portion attached to one side of the support via a first positioning mechanism, and the first detection portion is attached to the support portion, The second detector on the other side of the column Is a printing apparatus.

  [Operation / Effect] According to the first aspect of the present invention, the detection portion for detecting the side end is connected to the support portion attached to the one side of the column attached to the base via the first positioning mechanism. Since one detector is attached and the second detector is provided on the other side of the column, only the second detector can be easily attached in a state where it is separately positioned on the column after the column is attached to the noble stand. Manufacturing and adjustment are easy and can be performed at low cost.

  Moreover, in this invention, it is preferable to further provide the 2nd positioning mechanism which positions the said support | pillar and the said 2nd detection part with respect to the said mounting base (Claim 2). It is preferable that a mounting member to which the support column and the second detection unit are fixed is further provided, and the second positioning mechanism is configured to position the mounting member with respect to the mounting base.

Thereby, the support | pillar to which the 1st detection part was attached, and a 2nd detection part will be positioned, and attachment can be performed more easily. For attachment, the attachment member may be attached to the attachment base in a positioned state.
In the present invention, the detection unit is a one-side detection unit that detects the position of one end of the print medium, and further includes a second-side detection unit that detects the position of the other end of the print medium. The other side detection unit includes the other side first detection unit and the other side second detection unit paired with the other side first detection unit, and the attachment mechanism is attached to the mounting base. The other side strut and the other side support portion attached to one side of the other side strut via a positioning mechanism, and the other side first support portion is attached to the other side support portion, and the other side strut It is preferable that the said other side 2nd detection part is provided in the other side of (Claim 4).
Accordingly, it is possible to easily attach two sets of detection units for detecting the positions of the end portions on both sides of the print medium.

In the present invention, it is preferable that the first detection unit emits an electromagnetic wave, and the second detection unit detects an electromagnetic wave emitted by the first detection unit. .
Thereby, a detection part can be manufactured easily at low cost.

Moreover, in this invention, it is preferable that the said support | pillar is provided long in the substantially up-down direction, the said support part is attached to the downward position of the said support | pillar, and further provides the ventilation mechanism which blows an air current with respect to a said 1st detection part. Item 6).
Since the light projecting unit is resistant to obstacles such as paper dust against the light receiving unit, the first detection unit is provided below the support column provided in the vertical direction, and the paper dust is blown by blowing an airflow on the first detection unit. It is possible to reduce the adhesion of the paper and the like, and to further suggest the influence of the trouble caused by paper dust.

1 is a schematic configuration diagram illustrating an entire system including an inkjet printing apparatus according to an embodiment. It is a top view of the periphery of an inkjet head. It is a perspective view explaining the structure of the 1st printing unit 3b. FIG. 4 is a diagram illustrating the edge detection unit and its periphery. It is a perspective view which shows the attachment process of the edge detection part to a 1st printing unit. It is a perspective view which shows the attachment process of the edge detection part to a 1st printing unit. It is a side view which shows the attachment state of the edge detection part to a 1st printing unit.

  An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram schematically illustrating the entire inkjet printing apparatus according to the embodiment, and FIG. 2 is a plan view schematically illustrating the arrangement of components around the inkjet head. These show the rough arrangement of the main parts, and some are simplified, modified or omitted.
[Overall configuration of inkjet printing system 1]

  The ink jet printing system 1 according to the embodiment includes an ink jet printing apparatus 3, a paper feed unit 5, and a paper discharge unit 7.

  The ink jet printing apparatus 3 performs printing on a sheet-like continuous paper WP. The paper supply unit 5 holds a roll of continuous paper WP so as to be rotatable about a horizontal axis, and unwinds the continuous paper WP from the roll of continuous paper WP and supplies it to the inkjet printing apparatus 3. The paper discharge unit 7 winds the continuous paper WP printed by the inkjet printer 3 around the horizontal axis. If the supply side of the continuous paper WP is the upstream side and the discharge side of the continuous paper WP is the downstream side, the paper feed unit 5 is disposed on the upstream side of the inkjet printing apparatus 3, and the paper discharge unit 7 is on the downstream side of the inkjet printing apparatus 3. Is arranged.

  The inkjet printing apparatus 3 corresponds to the “printing apparatus” in the present invention, and the continuous paper WP corresponds to the “printing medium”.

  The ink jet printing apparatus 3 includes a driving roller 9 for taking in the continuous paper WP from the paper supply unit 5 on the upstream side. The continuous paper WP unwound from the paper supply unit 5 by the drive roller 9 is conveyed toward the downstream paper discharge unit 7 along a rotatable conveyance roller 11 and the like. A driving roller 13 is disposed on the upstream side of the paper discharge unit 7. The drive roller 13 sends out the continuous paper WP that has been printed and inspected to the paper discharge unit 7.

  The inkjet printing apparatus 3 is configured by dividing a plurality of units according to functions and connecting the plurality of units. In the present embodiment, the inkjet printing apparatus 3 includes five units including an entrance unit 3a, a first print unit 3b, a second print unit 3c, a second print unit 3c, a drying unit 3d, and an exit unit 3e. It consists of units 3a to 3e.

  The entrance unit 3a is provided with a driving roller 9, an edge position control mechanism 15, and a driving roller 17. The first printing unit 3b is provided with inkjet heads 19a and 19b that eject ink droplets. The second printing unit 3c is provided with inkjet heads 19c and 19d that eject ink droplets. The drying unit 3d is provided with a heat drum 21 that contacts the continuous paper WP and dries the ink droplets. The exit unit 3e is provided with an inspection unit 23 and a driving roller 13.

  In the present embodiment, the inkjet printing apparatus 3 is constituted by five units 3a to 3e, but the present invention is not limited to such a form. The inkjet heads 19a to 19d described above correspond to the “printing unit” in the present invention.

  The continuous paper WP is conveyed in the order of the driving roller 9, the edge position control mechanism 15, the driving roller 17, the inkjet heads 19 a to 19 e, the heat drum 21, the inspection unit 23, and the driving roller 13. The edge position control mechanism 15 automatically adjusts when the continuous paper WP meanders in a direction orthogonal to the transport direction, and controls the continuous paper WP to be transported to the correct position. However, since meandering cannot be completely prevented, the side edge of the continuous paper WP moves in the width direction of the continuous paper WP as will be described later. The drive roller 17 rotates at a constant speed and becomes a reference for the rotation speed of the other drive rollers 9 and 13 and the heat drum 21.

  A nip roller 25 is rotatably provided on each of the drive rollers 9, 13, and 17. The nip roller 25 provides a conveying force for the continuous paper WP. The pressing force by the nip roller 25 is applied by, for example, an air cylinder (not shown). The nip roller 25 is made of an elastic body such as rubber, for example.

  The inkjet heads 19 a to 19 d are arranged along a conveyance unit 27 formed along the plurality of conveyance rollers 11. Each of the inkjet heads 19a to 19d ejects, for example, black (K), cyan (C), magenta (M), and yellow (Y) ink droplets in order from the upstream side. Therefore, the inkjet printing apparatus 3 can perform four-color printing.

The heat drum 21 heats and dries the ink droplets adhering to the continuous paper WP by the inkjet heads 19a to 19d. The heat drum 21 incorporates a heater and is driven to rotate. The inspecting unit 23 inspects the printed portion for dirt or missing. The inspected continuous paper WP is wound around the paper discharge unit 8 in a roll shape.
[Configuration of Edge Detection Unit 29]

One side edge detector 29 is arranged at each of the positions on the upstream side of the inkjet heads 19 a to 19 d and on the left and right sides along the transport unit 27. As shown in FIGS. 2 and 4, the side edge detection unit 29 includes a light projecting unit 29 a that emits visible light and a light receiving unit 29 b that receives the visible light, which are on the side of the continuous paper WP. It is arranged so as to be separated from the top and bottom of the edge and has a function of detecting the side edge position (edge in the direction orthogonal to the transport direction) of the continuous paper WP. The side edge detector 29 is preferably a non-contact transmissive optical sensor that can detect the position of the side edge without contacting the side edge of the continuous paper WP. When comparing the light projecting unit 29a and the light receiving unit 29b, the light projecting unit 29a is less susceptible to light scattering by paper dust than the light receiving unit 29b. For this reason, the light projecting unit 29a is disposed at a position lower than the conveying height of the continuous paper WP, and the light receiving unit 29b is disposed at an upper position, respectively, so that there is little risk of erroneous detection due to the influence of paper dust. Further, a smooth flat glass 29c covering the entire surface of the light receiving portion 29b is attached for protection on the upper surface serving as the light receiving surface to prevent the accumulation of paper dust, and the influence thereof is further reduced. Although the light projecting unit 29a is below the light receiving unit 29b and the continuous paper WP, it does not appear in FIG. 2, but a fan 60 that is a blower and a fan 60 are generated for each light projecting unit 29a. Provided with a blowing mechanism composed of a duct 61 for guiding the airflow and a nozzle 62 for blowing the airflow to each light projecting portion 29a, and air is sent to the smooth flat glass 29c which is a light receiving surface of the light projecting portion 29a. Further, the paper dust generated along with the conveyance of the continuous paper WP is prevented from adhering to the light projecting unit 29a, and adverse effects such as erroneous detection due to the influence of the paper dust are reduced. The light projecting unit 29a and the light receiving unit 29b are attached to the ink jet printing apparatus 3 as will be described later, and the side edge detecting units 29 are attached to the corresponding ink jet heads 19a to 19d with high accuracy. Yes. The transport unit 27 including the transport roller 11 described above corresponds to the “transport mechanism” in the present invention, and the side plate 31 to which they are attached corresponds to the “base”.
[Configuration of First Printing Unit 3b]

The configuration including the above-described inkjet heads 19a to 19d and their peripheral portions will be described in detail below. Here, the configuration of the vicinity of the inkjet heads 19a and 19b of the first printing unit 3b will be described, but the second printing unit 3c also has the same configuration except for the inkjet heads 19c and 19d. FIG. 3 is a perspective view showing a detailed configuration of the first printing unit 3b. The inkjet heads 19a and 19b incorporate therein an inkjet nozzle that ejects ink droplets and a mechanism that drives or moves them. The inkjet heads 19a and 19b are attached to the side plate 31 via a pair of head stays 35 attached so as to be bridged over the upper edges of the side plate 31 provided on the left and right in the transport direction. The head stay 35 supports the inkjet heads 19a and 19b in a slidable state in a horizontal direction perpendicular to the conveyance direction of the continuous paper WP. A sensor base 37 is bridged between the left and right side plates 31 along the head stay 35 on the upstream side in the transport direction of each inkjet head 19a, 19b. A sensor positioning member 39 is attached above the sensor base 37. The sensor unit 40 is attached to the sensor base 37 in a state where the sensor unit 40 is positioned by the sensor positioning member 39.
[Detailed Configuration of Sensor Unit 40]

  The sensor unit 40 has a sensor mounting plate (mounting member) 41 having substantially the same length as the width of the continuous paper WP serving as a printing medium, and a substantially “gate” shape at both ends of the sensor mounting plate 41. A pair of sensor stays 42 attached to hang downward and a pair of edge detection units 29 and 29 supported by the sensor stays 42 and 42 are provided. Of the pair of side end detection units 29 corresponding to one inkjet head, two light receiving units 29b and 29b are attached to the upper portions of the sensor stays 42 and 42 with their light receiving surfaces facing downward. Sensor support portions 43 and 43 are detachably attached to the lower portions of the sensor stays 42 and 42 via positioning and fixing mechanisms 44 (first positioning mechanism: described later). Two light projecting parts 29a and 29a corresponding to the two light receiving parts 29b and 29b are attached. The two light projecting portions 29a and 29a are opposite to the two light receiving portions 29b and 29b provided on the same sensor stays 42 and 42, respectively. The light projecting unit 29a and the light receiving unit b are fixed so that the optical axis is perpendicular to the surface of the continuous paper WP, and the edge of the continuous paper WP to be positioned between them can be detected.

4A and 4B are side views showing details of the sensor stay 42 and the edge detection unit 29. FIG. 4A is a side view showing a state where the light projecting unit 29a is separated. FIG. 4B is a side view showing the light projecting unit 29a. FIG. 4C is a cross-sectional view showing the attachment and positioning mechanism of the light projecting portion 29a. The light receiving portion 29b is attached to the sensor mounting plate 41 through the upper portion of the sensor stay 42 with its light receiving surface facing downward. A sensor support portion 43 is detachably attached to the lower portion of the sensor stay 42 via a positioning and fixing mechanism 44. The positioning and fixing mechanism 44 mainly includes two long and short position positioning protrusions 45 and 46 projecting above the sensor support portion 43, and a sensor stay 42 that is positioned with the positioning protrusions 45 and 46 inserted thereinto. It consists of positioning holes 47 and 48 formed in the end face. Further, the longer positioning projection 45 is provided with a dropping prevention mechanism. This drop-off prevention mechanism is provided with a constricted portion 45a in the middle of the positioning projection 45, and when the positioning projection 45 is fitted in the corresponding positioning hole 47, it engages with the constricted portion 45a. An engaging pin 49 that fixes the positioning protrusion 45 and prevents its falling off is provided by being urged in a protruding direction toward the positioning hole 47 by an elastic member (not shown). Further, a screw hole 50 is formed in the sensor support portion 43 in the lateral direction. When the sensor support portion 43 is attached near the lower end of the sensor stay 42, the sensor support portion 43 communicates with the screw hole 50 and is fixed by the screw 51. There is provided a fixing mechanism to which a fixing member 53 having a screw hole 52 is attached.
[Attachment of Edge Detection Unit 29 to First Printing Unit 3b]

  A structure and method for attaching the edge detection unit 29 to the first printing unit 3b will be described in detail below. As described in [Configuration of the first printing unit 3b], the first printing unit 3b including the side plates 31 and 31 to which the inkjet heads 19a and 19b, the sensor positioning member 39, and the like are attached is prepared. However, the sensor unit 40 is not yet attached to the sensor positioning member 39, and the sensor support portions 43 and 43 to which the two light projecting portions 29 a and 29 a are attached are not attached to the sensor stays 42 and 42. This state is shown in FIG. Here, a stopper 39a protrudes from one end edge (here, the end edge on the right side in the transport direction) of the sensor positioning member 39 toward the side where the sensor unit 40 is attached, that is, the upstream side in the transport direction. A pair of upper and lower positioning protrusions 39b and 39b protrude from the inner surface of the stopper 39a (here, the surface on the left side in the transport direction). On the other hand, a pair of upper and lower positioning holes (not shown) in which the positioning projections 39b and 39b are fitted and positioned with respect to each other on the right edge in the transport direction of the sensor mounting plate 41 constituting the sensor unit 40 are formed. These components constitute a positioning mechanism 440 (second positioning mechanism).

  Thus, when the sensor unit 40 including the edge detection portion 29 is attached to the first printing unit 3b, the sensor support portion 43 and the light projecting portion 29a are first attached to the sensor stay 42 from the state shown in FIG. The sensor mounting plate 41 of the sensor unit 40 is lifted by the upper body that is not provided, and is lowered with the sensor stay 42 downward from the upper side of the surface of the sensor positioning member 39 (the rear surface in the transport direction). While positioning the mounting plate 41 along the surface of the sensor positioning member 39 (surface on the rear side in the transport direction) and moving the sensor mounting plate 41 toward the right side in the transport direction, the positioning protrusions 39b and 39b of the sensor positioning member 39 are The edge of the sensor mounting plate 41 is brought into contact with the stopper 39a while being fitted into the above-described pair of upper and lower positioning holes on the right edge of the mounting plate 41 in the conveying direction. . Then, the sensor mounting plate 41 is fixed with screws or the like (not shown). Thus, the sensor unit 40 is positioned at the correct position. This state is shown in FIG. The sensor unit 40 positioned between the inkjet head 19a and the inkjet head 19b is lowered so that the sensor stay 42 does not hit the side plate 31, the head stay 35, the sensor base 37, or the like.

Subsequently, from the state of FIG. 6, the light projecting portion 29 a attached to the sensor support portion 43 is taken below each sensor stay 42 and moved upward from below to fit the positioning fixing mechanism 44 to each sensor. The sensor support portion 43 and the light projecting portion 29a are attached to the stay 42. Due to the fixing function of the positioning and fixing mechanism 44, the sensor support portion 43 does not fall off even if the sensor support portion 43 is not held by a person. Thereafter, the sensor support portion 43 is fixed to the sensor stay 42 with the screw 51. In this way, the attachment of the edge detection unit 29 is completed as in the state shown in FIG. In this case, a positioning mechanism is provided between the sensor positioning member 39 and the sensor mounting plate 41, and the sensor stay 42 and the sensor support portion 43. Since the position of the edge detection unit 29 is maintained correctly, the operation is easy and the cost is low. Further, since the sensor support portion 43 to which the light projecting portion 29a is attached and the sensor stay 42 to which the light receiving portion 29b is attached are separable and a positioning mechanism is provided, for example, an inkjet head 19a as shown in FIG. Even if the gap between the inkjet head 19b and the head stay 35 of the inkjet head 19a and the head stay 35 of the inkjet head 19b is narrower than the width of the light projecting portion 29a and the light receiving portion 29b, a narrow sensor stay 42 is provided in the gap. The light projection part 29a and the light-receiving part 29b can be installed by passing.
[Operation of Inkjet Printing System 1]

When the ink jet printing system 1 is used, the above-described ink jet printing apparatus 3, the paper feed unit 5, and the paper discharge unit 7 are collectively controlled by the main control unit 49. The main control unit 49 controls the rotational driving of the drive rollers 9, 13, and 17, controls the temperature of the heat drum 21, and controls the inspection by the inspection unit 23. The control unit 49 recognizes the edge position detected by each side edge detection unit 29, and discharges ink droplets from the inkjet heads 19a to 19d while correcting the printing position at the side edge during printing. To print.
[Modification]

  The present invention is not limited to the above embodiment, and can be modified as follows.

(1) In the above-described embodiment, the side edge detection units 29 are provided on both sides of the continuous paper WP, but may be provided only on one side. In this case, the side end detector 29 may be attached to only one side of the sensor unit 40, and the sensor attachment plate 41 has substantially the same length as the width of the continuous paper WP as long as the positioning hole 41a can be provided. There is no need for it and it is small.
(2) In the above-described embodiments, the side edge detection unit uses visible light. However, the present invention is not limited to this, and other side electromagnetic waves such as infrared rays and X-rays may be used.

WP ... Continuous paper (printing medium)
DESCRIPTION OF SYMBOLS 1 ... Inkjet printing system 3 ... Inkjet printing apparatus 5 ... Paper feed part 7 ... Paper discharge part 19a-19d ... Inkjet head (printing part)
27 ... Conveying section (conveying mechanism)
29 ... Side end detection part (detection part)
29a: Light projecting unit (first detecting unit)
29b ... Light receiving part (second detection part)
31 ... Side plate (base)
39 ... Sensor positioning member 39a ... Stopper 39b ... Positioning projection 40 ... Sensor unit 41 ... Sensor mounting plate 41a ... Positioning hole 42 ... Sensor stay 43 ... Sensor support 44 ... Positioning fixing mechanism 45, 46 ... Positioning projection 47, 48 ... Positioning Hole 60 ... Fan 61 ... Duct 62 ... Nozzle 440 ... Positioning mechanism

Claims (6)

A printing apparatus that conveys a print medium and performs printing while detecting the position of the end of the print medium,
A base to which a transport mechanism for transporting the print medium is attached;
A printing unit that performs printing on the print medium conveyed by the conveyance mechanism;
A detection unit disposed along the transport mechanism and detecting a side edge position of the print medium;
An attachment mechanism for attaching the detection unit to a base;
With
The detection unit includes a first detection unit and a second detection unit paired with the first detection unit,
The attachment mechanism is
A mounting base provided on the base;
A column attached to the mounting base;
Having a support portion attached to one side of the column via a first positioning mechanism;
The printing apparatus, wherein the first detection unit is attached to the support unit, and the second detection unit is provided on the other side of the support column. The printing apparatus according to claim 1,
A printing apparatus, further comprising a second positioning mechanism for positioning the support and the second detection unit with respect to the mounting base. The printing apparatus according to claim 2,
The printing apparatus according to claim 1, further comprising an attachment member to which the support column and the second detection unit are fixed, wherein the second positioning mechanism positions the attachment member with respect to the attachment base. The printing apparatus according to claim 3,
The detection unit is a one-side detection unit that detects the position of one end of the print medium,
Furthermore, the other side detection unit for detecting the position of the other end of the print medium,
The other side detection unit includes the other side first detection unit and the other side second detection unit paired with the other side first detection unit,
The attachment mechanism is
The other side column attached to the mounting base;
Having the other side support part attached to one side of the other side column through a positioning mechanism;
The printing apparatus, wherein the other side first detection unit is attached to the other side support unit, and the other side second detection unit is provided on the other side of the other side support column. The printing apparatus according to any one of claims 1 to 4,
The printing apparatus, wherein the first detection unit emits an electromagnetic wave, and the second detection unit detects an electromagnetic wave emitted by the first detection unit. The printing apparatus according to claim 5,
The support column is provided long in a substantially vertical direction, and the support portion is attached to a lower position of the support column,
A printing apparatus, further comprising a blower mechanism that blows an airflow against the first detection unit.

Images