JP2001063870A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cause no dispersion in a printed result depending on the kind of a medium. SOLUTION: This printer has a conveying means for conveying a medium 56; a light emitting part 61 disposed facing one face of the medium 56 to emit light; a first light receiving part 62 disposed facing one face of the medium 56 to receive light emitted by the light emitting part 61 and reflected by the medium 56; a second light receiving part 63 disposed facing the other face of the medium 56 to receive light emitted by the light emitting part 61 and transmitted through the medium 56; and a medium judging means for judging the kind of the medium 56 on the basis of the light receiving quantity of the first and second light receiving parts 62, 63. Since the drive mode of a recording head can be selected on the basis of the judged result, there is no dispersion in a printed result caused by the kind of the medium 56.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer.

[0002]

2. Description of the Related Art Conventionally, as a printer apparatus for recording images such as characters and patterns on a medium such as paper, for example, high-speed recording can be performed without generating noise, and a special fixing process is required. No inkjet recording device is used. In the inkjet recording apparatus, ink droplets are ejected toward the medium by an inkjet head. As a method of discharging the ink droplets, there are an electrostatic method, a bubble method in which ink is heated to generate air bubbles, a piezoelectric method using a piezoelectric element such as a piezo element, and the like.

For example, in the piezoelectric type ink jet head, the ink droplets are ejected by utilizing the deformation of the piezoelectric body, so that the ink is not thermally degraded, and By controlling the applied voltage, it is possible to control the deformation of the piezoelectric body and to control the pressing force of the ink, so that it is possible to perform not only resistance to disturbance but also gradation printing.

For this purpose, a plurality of ink pressurizing chambers are formed, and an orifice plate is attached so as to cover one end of each of the ink pressurizing chambers. An orifice is formed for discharge. Then, when the wall is deformed by applying a voltage to the piezoelectric body constituting the wall of the ink pressurizing chamber, pressure is applied to the ink in the ink pressurizing chamber, and ink droplets are ejected from the orifice.
The amount of deformation of the wall is determined by the voltage applied to the piezoelectric body and the driving time.

[0005]

However, in the above-mentioned conventional ink jet recording apparatus, as a medium,
When OHP paper is used, when glossy paper is used, when plain paper is used, the adhesion state of ink droplets changes, and printing results vary.

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the above-mentioned conventional ink jet recording apparatus and to provide a printer apparatus in which printing results do not vary depending on the type of medium.

[0007]

For this purpose, in the printer device of the present invention, a transporting means for transporting a medium, a light emitting unit arranged to face one surface of the medium and generating light, and A first light receiving unit that is disposed facing one surface of the medium and receives light generated by the light emitting unit and reflected by the medium; and a first light receiving unit that is disposed facing the other surface of the medium. A second light receiving unit that receives light generated by the light emitting unit and transmitted through a medium, and a medium determining unit that determines a type of the medium based on the amount of light received by the first and second light receiving units. .

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings. In this case, an ink jet recording apparatus will be described as a printer apparatus.

FIG. 1 is an enlarged view of a medium detection unit according to the first embodiment of the present invention, FIG. 2 is a schematic diagram of an ink jet recording apparatus according to the first embodiment of the present invention, and FIG. FIG. 4 is a front view of the medium sensor according to the first embodiment, FIG. 4 is a side view of the medium sensor according to the first embodiment of the present invention, and FIG. 5 is an operation explanatory diagram of the medium sensor according to the first embodiment of the present invention. It is.

In the figure, 41 is a base frame, 43
Denotes an ink jet head as a recording head; 45, an ink tank; 47, a shaft provided on a side frame (not shown); 48, a carriage frame assembly movably disposed along the shaft 47; At 48, the ink jet head 43 and the ink tank 45 are attached. The carriage frame assembly 4
8 is driven by driving a carriage motor (not shown) as first driving means.

Reference numeral 51 denotes an upper cover. The upper cover 51 has a medium insertion port 52 and a medium discharge port 53.
Is formed. A paper cassette 55 as a medium receiver is disposed adjacent to the medium insertion opening 52, and a medium 56 such as paper is stored in the paper cassette 55. The medium 56 fed out of the paper cassette 55 is guided by a curved guide 65 provided in the medium insertion port 52, and guided by a guide 66 provided to face the ink jet head 43, and a printing unit is provided. It passes through Pr and is discharged from the medium discharge port 53. Note that R1 is the second
The transport roller R2 is rotated by driving a paper feed motor (not shown) as a driving means, and the discharge roller R2 is rotated by driving a motor for transporting a medium (not shown). The paper feed motor, the transport roller R1, and the discharge roller R2 constitute a transport unit.

A medium detecting portion Sn for detecting the medium 56 is formed in the medium insertion opening 52. In the medium detecting portion Sn, a light emitting portion 61 is provided so as to face the front side as one surface of the passing medium 56. And a first light receiving unit 62 is provided, and a second light receiving unit 63 is provided facing the back side as the other surface of the medium 56. The first light receiving unit 62 is located at a position capable of receiving the light generated by the light emitting unit 61 and reflected by the medium 56. The second light receiving section 63 is located at a position where it can receive the light generated by the light emitting section 61, transmitted through the medium 56, and further transmitted through the transmission hole 67 formed in the guide 65. The light emitting unit 61 and the second light receiving unit 63 are used by the light emitting unit 61 and the first light receiving unit
Constitutes a second sensor. When receiving the light, the first and second light receiving units 62 and 63 generate a light reception detection signal indicating the amount of received light, and send the light reception detection signal to the control device 68.

The front end of the medium 56 (the left end in the figure)
Is activated when it reaches the medium detecting portion Sn, and a mechanical medium sensor 71 that mechanically detects the front end of the medium 56
Is arranged. The medium sensor 71 includes a detection target 73 that is swingably disposed around a shaft 72, and a U-shaped cross-section sensor disposed corresponding to the detection target 73. The light emitting unit 61 is disposed upstream of a portion where the light generated by the light emitting unit 61 is reflected and transmitted in the transport direction of the medium 56. The detected object 73 includes an abutting portion 76 at an upper end thereof for abutting on the medium 56, and a magnet portion 75 at a lower end selectively placed in the sensor body 74 with swinging. .
When the front end of the medium 56 has not reached the medium detection unit Sn, the detection target 73 is placed at the medium non-detection position shown in FIGS.
5 is placed in the sensor body 74. Further, when the front end of the medium 56 reaches the medium detecting portion Sn and presses the contact portion 76, the detected object 73 is rotated and placed at the medium detecting position shown in FIG. The magnet 75 is placed outside the sensor body 74. As a result, the sensor body 74 generates a medium detection signal and sends it to the control device 68.

Next, the configuration of the ink jet head 43 will be described.

FIG. 6 is a perspective view of the ink jet head according to the first embodiment of the present invention, and FIG. 7 is a side view of the ink jet head according to the first embodiment of the present invention.

As shown in the drawing, in the ink jet head 43, a plurality of ink pressurizing chambers 13 are formed in the piezoelectric body 11, and the ink is stored in each of the ink pressurizing chambers 13. An orifice plate 15 is attached to the piezoelectric body 11 so as to cover one end of the ink pressurizing chamber 13, and the other end of the ink pressurizing chamber 13 has a manifold 14 communicating with an ink tank 45 (FIG. 2). Is attached. A plurality of orifices 16 for ejecting ink droplets are formed in the orifice plate 15 in correspondence with the respective ink pressurizing chambers 13.

When a voltage is applied to the piezoelectric body 11 by a piezoelectric body driving means (not shown) in the control device 68, a wall (not shown) forming the ink pressurizing chamber 13 is deformed, and the ink in the ink pressurizing chamber 13 is deformed. When pressure is applied, ink droplets are ejected from the orifice 16. Then, the ink in the ink tank 45 is supplied to the ink pressurizing chamber 13 via the manifold 14.

When the ejected ink droplets reach the medium 56, they form dots on the medium 56. As a result, an image is recorded on the medium 56 and printing is performed.

Next, the piezoelectric body 11 will be described.

FIG. 8 is a diagram showing the principle of operation of the piezoelectric body according to the first embodiment of the present invention.

In the drawing, reference numeral 31 denotes a piezoelectric base which is polarized in the direction of arrow P (array direction) and is formed in a comb-like shape by a plurality of protrusions 21, and 32 corresponds to each of the protrusions 21. The intermediate piezoelectric body is disposed in such a manner as to be polarized in the same arrow P direction as the piezoelectric body base 31. The intermediate piezoelectric body 32 is composed of a plurality of walls 22 formed corresponding to the respective projections 21.

An electrode 2 is attached to the tip of each of the projections 21.
6 are formed, and electrodes 27 and 28 are provided at both ends of each wall portion 22.
Is formed, and a conductive adhesive member 30 is provided between the electrodes 26 and 27.
Is disposed, and the intermediate piezoelectric body 3 is
2 is fixed to the piezoelectric base 31.

A plurality of grooves are formed between the projections 21 and between the walls 22, and each of the grooves is closed by a top plate 33 to form the ink pressurizing chamber 13. A common electrode 29 is formed on the top plate 33, and a conductive adhesive member 23 is disposed between the common electrode 29 and each electrode 28. Fixed to Reference numeral 16 denotes an orifice.

In the piezoelectric body 11 having the above structure, for example,
The common electrode 29 is grounded, and the electrode 26 of a certain projection 21 is
When a positive voltage + V is applied to the electrode 21 and a negative voltage −V is applied to the electrode 26 of the adjacent protrusion 21, an electric field in the direction of arrow A is generated in the protrusion 21, and an electric field in the direction of arrows B and C is generated in the intermediate piezoelectric body 32. Let me do. As a result, a shearing (shearing) mode deformation (broken line shape) is generated in the projection portion 21 and the intermediate piezoelectric body 32 in the opposite directions, and pressure is applied to the ink in the ink pressurizing chamber 13, and Ink droplets are ejected from.

Next, a control circuit of the ink jet recording apparatus having the above configuration will be described.

FIG. 9 is a control circuit diagram of the ink jet recording apparatus according to the first embodiment of the present invention.

In the figure, 43 is an ink jet head, 61 is a light emitting unit, 62 is a first light receiving unit, 63 is a second light receiving unit, 68 is a control device, 74 is a sensor unit, 81 is a host computer, and 82 is an operation unit. Panel, 83 is medium 56
A paper feed motor 84 for transporting (FIG. 2) is a carriage motor for running the carriage frame assembly 48.

The controller 68 includes a main controller 85, a head driver 86 for driving the ink-jet head 43,
An interface (I / I / O) for connecting the light emitting unit 61, the first and second light receiving units 62 and 63, the sensor controller 87 for controlling the sensor body 74, and the host computer 81.
F) 88, a motor driver 89 for driving the paper feed motor 83, a motor driver 90 for driving the carriage motor 84, a ROM 91 storing a program (not shown) for operating the main control unit 85, and the like.

Next, the ink jet head 4 having the above configuration
Operation 3 will be described.

FIG. 10 is a flowchart showing the operation of the ink jet head according to the first embodiment of the present invention.

When a print command is sent from the host computer 81 (FIG. 9) to the controller 68, the main controller 85
Receives the print command via the interface 88, drives the paper feed motor 83 via the motor driver 89, conveys the medium 56 (FIG. 2), and operates the light emitting unit 61 via the sensor controller 87. The light emitting section 61 generates light. Then, when the front end of the medium 56 reaches the medium detecting portion Sn and presses the contact portion 76 (FIG. 5), the detected object 73 is rotated and placed at the medium detecting position shown in FIG. At the medium detection position, the magnet section 75 is moved out of the sensor body 74. As a result, the media sensor 71
As a result, the front end of the medium 56 is detected, and the sensor body 74 generates a medium detection signal and sends it to the control device 68. And
The main control unit 85 receives the medium detection signal via the sensor controller 87, and the front end of the medium 56 is connected to the medium detection unit Sn.
Is determined to have been reached.

Subsequently, when the medium 56 is further conveyed and enters between the light emitting section 61 and the second light receiving section 63, the type of the medium 56 is determined by a medium determining means (not shown) in the main control section 85. . In the present embodiment, the type of the medium 56 is determined by determining whether the reflectance and the transmittance of the medium 56 are high.

For this purpose, a not-shown received light amount judging means in the main control section 85 receives the received light detection signals sent from the first and second light receiving sections 62 and 63 via the sensor controller 87 and detects the received light. Based on the signal, it is determined whether the first and second light receiving units 62 and 63 have a large amount of received light. When the amount of light received by the second light receiving unit 63 is large, it is possible to determine that the reflectance of the medium 56 is low and the transmittance is high, so that the medium determination unit determines that the medium 56 is OHP paper. . Further, the amount of light received by the first light receiving unit 62 is large,
If the light receiving amount of the light receiving unit 63 is small, it can be determined that the medium 56 has a high reflectance and a low transmittance, so that the medium determining unit determines that the medium 56 is glossy paper.
When the light receiving amounts of the first and second light receiving units 62 and 63 are small, it is possible to determine that both the reflectance and the transmittance of the medium 56 are low.
6 is determined to be plain paper.

The drive modes of the inkjet head 43 are set in accordance with the type of the medium 56, and the drive settings of the inkjet head 43 in each drive mode are stored in the ROM 91 as a drive setting table. Therefore, the drive mode selection unit (not shown) in the main control unit 85 selects the drive mode based on the determination result of the medium 56, and the drive unit (not shown) in the main control unit 85 refers to the drive setting table, Drive settings for OHP paper, glossy paper, and plain paper are performed in accordance with each drive mode, and the inkjet head 43 is driven based on the drive settings to perform a printing operation.

In this embodiment, an OHP paper drive mode, a glossy paper drive mode, and a plain paper drive mode are set as drive modes. When the OHP paper drive mode is selected, the drive setting for OHP paper is performed. In general, large characters and the like are often coarsely printed on OHP paper. Therefore, in the drive setting for OHP paper, the piezoelectric body 1 is designed so that ink droplets can be enlarged.
1 (FIG. 8) is extended. Further, when the glossy paper drive mode is selected, drive setting for glossy paper is performed, so that not only the drive time of the piezoelectric body 11 is shortened but also the resolution is increased so that ink droplets can be reduced. And the spacing speed is reduced. In order to lower the spacing speed, the rotation speeds of the paper feed motor 83 and the carriage motor 84 are reduced. Then, when the plain paper drive mode is selected, drive setting for plain paper is performed, and the drive time of the piezoelectric body 11 is standardized so that the ink droplets can be made normal.

As described above, depending on the case where OHP paper is used as the medium 56, the case where glossy paper is used, the case where plain paper is used, etc., each drive setting for OHP paper, glossy paper, plain paper, etc. Is performed, the adhesion state of the ink droplets can be made constant. Therefore, the printing result does not vary depending on the type of the medium 56.

If the medium 56 is not fed out of the paper cassette 55 for some reason, the medium sensor 71 does not detect the front end of the medium 56. Therefore, even if the amount of light received by the second light receiving unit 63 is large, it is possible to prevent erroneous determination that the medium 56 is OHP paper.

In the present embodiment, the front end of the medium 56 is detected by the medium sensor 71, and cueing of the medium 56 is performed. However, glossy paper or plain paper is used as the medium 56. In the case, the medium sensor 71
Is not provided, the front end of the medium 56 can be detected and cueing of the medium 56 can be performed by determining whether the second light receiving unit 63 has received light. Also,
When OHP paper is used as the medium 56, the light reflected by the medium 56 can be sufficiently received by the first light receiving unit 62 depending on the angle of incidence of the light incident on the medium 56. Therefore, the mounting position of the light emitting section 61 and the first light receiving section 62 is changed without disposing the medium sensor 71, and it is determined whether the first light receiving section 62 has received light. Of the medium 56 can be detected.

Although the present embodiment has been described with respect to an ink jet recording apparatus, the present invention can be applied to various recording apparatuses such as a thermal printer and an electrophotographic printer.

Next, the flowchart will be described. Step S1 A print command is sent. Step S2: The medium 56 is transported. Step S3 Light is generated by the light emitting section 61. Step S4: It is determined whether or not the light receiving amount of the second light receiving unit 63 is large. If the amount of received light is large, the process proceeds to step S5, and if it is small, the process proceeds to step S6. Step S5 Drive setting for OHP paper is performed. Step S6: It is determined whether or not the light receiving amount of the first light receiving unit 62 is large. When the amount of received light is large, the process proceeds to step S7, and when it is small, the process proceeds to step S8. Step S7: Set the drive for glossy paper. Step S8 Drive setting for plain paper is performed. Step S9 Perform a printing operation.

Next, a second embodiment of the present invention will be described. In addition, about what has the same structure as 1st Embodiment, the description is abbreviate | omitted by attaching the same code | symbol.

FIG. 11 is an enlarged view of the medium detecting section according to the second embodiment of the present invention.

In this case, in the medium detecting section Sn, the first side of the medium 56 passing therethrough is faced to the front side as one surface.
A second light emitting unit 96 and a second light receiving unit 98 are provided facing the back side of the medium 56 as the other surface. The first light receiving unit 97 can receive light generated by the first light emitting unit 95 and reflected by the medium 56, generated by the second light emitting unit 96, and formed on the guide 65. It is placed at a position where it can receive the light that has passed through the transmission hole 67 and has further passed through the medium 56. Further, the second light receiving section 98 can receive the light generated by the first light emitting section 95 and transmitted through the medium 56 and further transmitted through the transmission hole 67. And is positioned to receive the light reflected by the medium 56.

In this case, the received light amount judging means (not shown) in the main control unit 85 (FIG. 9) activates only the first light emitting unit 95 to generate light in the first stage, and generates the second received light. Part 9
Then, it is determined whether or not the light receiving amount of No. 8 is large. When the amount of light received by the second light receiving unit 98 is large, it is possible to determine that the reflectance of the medium 56 is low and the transmittance is high. OH
It is determined that the sheet is P paper.

The light receiving amount determining means operates the first and second light emitting portions 95 and 96 in the second stage, and
The light receiving amounts of the second light receiving units 97 and 98 are compared. And
When the amount of light received by the first light receiving unit 97 is larger than the amount of light received by the second light receiving unit 98, it is possible to determine that the reflectance on the front side of the medium 56 is high and the reflectance on the back side is low. The means determines that the medium 56 is glossy paper. And
When the light receiving amounts of the first and second light receiving portions 97 and 98 are substantially equal, it is possible to determine that the reflectance on the front side and the reflectance on the back side of the medium 56 are equal. It is determined that the sheet is paper. Further, when the amount of light received by the first light receiving unit 97 is smaller than the amount of light received by the second light receiving unit 98, it can be determined that the reflectance on the front side of the medium 56 is low and the reflectance on the back side is high. The medium determination means determines that the medium 56 is glossy paper, but the paper cassette 5 is turned upside down.
5 is determined to be accommodated. In this case, the main control unit 8
The warning means (not shown) in 5 sends an error message to a display (not shown) in the operation panel 82, and the medium 56
Display that there is an error in the type, setting method, etc. of the
Can be stopped.

In the present embodiment, in the first stage,
The first light emitting unit 95 generates light and the second light receiving unit 98 receives light. However, the second light emitting unit 96 generates light and receives light by the first light receiving unit 97. You can also do so.

The present invention is not limited to the above embodiment, but can be variously modified based on the gist of the present invention, and they are not excluded from the scope of the present invention.

[0048]

As described above in detail, according to the present invention, in a printer device, a transporting means for transporting a medium and a light emitting device are provided so as to face one surface of the medium. A light-emitting unit, a first light-receiving unit arranged to face one surface of the medium, receiving light generated by the light-emitting unit and reflected by the medium, and facing a second surface of the medium. A second light receiving unit that is disposed and receives the light generated by the light emitting unit and transmitted through the medium, and a medium determination unit that determines the type of the medium based on the amount of light received by the first and second light receiving units Means.

In this case, if the amount of light received by the second light receiving portion is large, it is possible to determine that the reflectance of the medium is low and the transmittance is high, so that the medium determining means determines that the medium is OHP paper. . When the amount of light received by the first light receiving unit is large and the amount of light received by the second light receiving unit is small, it can be determined that the medium has a high reflectance and a low transmittance. Is determined to be glossy paper. And the first,
When the amount of light received by the second light receiving unit is small, it can be determined that both the reflectance and the transmittance of the medium are low, so the medium determination unit determines that the medium is plain paper.

Therefore, since the drive mode of the recording head can be selected based on the determination result, the print result does not vary depending on the type of the medium.

[Brief description of the drawings]

FIG. 1 is an enlarged view of a medium detection unit according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram of an ink jet recording apparatus according to the first embodiment of the present invention.

FIG. 3 is a front view of the medium sensor according to the first embodiment of the present invention.

FIG. 4 is a side view of the medium sensor according to the first embodiment of the present invention.

FIG. 5 is an operation explanatory diagram of the medium sensor according to the first embodiment of the present invention.

FIG. 6 is a perspective view of the inkjet head according to the first embodiment of the present invention.

FIG. 7 is a side view of the inkjet head according to the first embodiment of the invention.

FIG. 8 is a diagram illustrating the principle of operation of the piezoelectric body according to the first embodiment of the present invention.

FIG. 9 is a control circuit diagram of the ink jet recording apparatus according to the first embodiment of the present invention.

FIG. 10 is a flowchart illustrating an operation of the inkjet head according to the first embodiment of the present invention.

FIG. 11 is an enlarged view of a medium detection unit according to the second embodiment of the present invention.

[Explanation of symbols]

 43 Inkjet head 56 Medium 61 Light emitting unit 62, 97 First light receiving unit 63, 98 Second light receiving unit 83 Paper feed motor 85 Main control unit 95, 96 First, second light emitting unit R1 Transport roller R2 Discharge roller

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C056 EB13 EB45 2C058 AB17 AC07 AD04 AE09 AE10 AF15 GB04 GB16 GB30 GB47 GE01 3F048 AA05 AB01 BA06 BB05 BD07 CC01 DB01 DC13 DC14 EB29

Claims (3)

[Claims] (A) transport means for transporting a medium;
(B) a light-emitting unit disposed to face one surface of the medium to generate light; and (c) a light-emitting unit disposed to face one surface of the medium and generated by the light-emitting unit. A first light receiving unit for receiving light reflected by the medium; and (d) a second light receiving unit disposed to face the other surface of the medium and receiving light generated by the light emitting unit and transmitted through the medium. A printer apparatus, comprising: a light receiving unit; and (e) a medium determining unit that determines a type of a medium based on the amount of light received by the first and second light receiving units. 2. The printer device according to claim 1, further comprising a drive mode selection unit that selects a print head drive mode based on a result of the determination by the medium determination unit. (A) the light emitting unit is a first light emitting unit; and (b) a second light emitting unit for generating light is provided facing the other surface of the medium. The second light receiving unit is configured to generate at least one of light generated by the first light emitting unit and transmitted through a medium, and light generated by the second light emitting unit and reflected by the medium. The printer device according to claim 1, which receives the information.