JP2008179107A - Printer and printing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printer which enables miniaturization while improving the energy efficiency by detecting the drying state of an object to be dried, and a printing method for producing a printed matter of high quality. <P>SOLUTION: The printer 1 has a recording head 2 used as a droplet discharge head which arranges droplets 8 on a paper 10 used as the dried object, and is equipped with an oscillator 100 used as a microwave generation section for generating a microwave 100a, a microwave switching section 550 for changing an irradiation course of the microwave 100a, a detection part 4 for detecting the state before and after printing the paper 10, a microwave heating mechanism 6 used as a microwave heating part for heating the droplets 8 arranged on the paper 10 and a control part for controlling the microwave heating mechanism 6 based on the result detected by the detection part 4. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a printer that arranges droplets and heats and dries, and a printing method using the printer.

  2. Description of the Related Art Conventionally, printers are used as devices that print character information, image information, and the like on paper, and are used not only at work and home but also for commercial purposes. For example, as a commercial printing technique, there is a line head type ink jet printer (hereinafter referred to as LIJP), and this LIJP can easily achieve higher image quality than a laser printer. In addition, it attracts attention as an inexpensive and easy-to-install printing technique that replaces offset printing. However, since much time is required for the process of drying the ink, there is a problem that it is difficult to perform high-speed printing as compared with a laser printer.

  For example, as disclosed in Patent Document 1, there has been proposed a method of heating and drying ink adhering to printing paper using a microwave. Since microwaves have a large effect on a substance having a high dielectric constant, the heating effect on ink having a high water content is high. By irradiating microwaves on paper that has been printed and drawn with ink and has not been dried, the effect of promoting heat drying can be expected.

JP 2006-134621 A

  However, the method of Patent Document 1 does not include means for detecting the dry state of the object to be heated (the object to be dried). For this reason, constant microwave energy was always irradiated regardless of the dry state of the heating object. Therefore, it is difficult to optimize the drying state of the heating object, which may cause variations in print quality. Moreover, since the output adjustment of microwave energy cannot be performed, energy may be consumed wastefully and it is difficult to realize energy saving.

  SUMMARY OF THE INVENTION An object of the present invention is to detect a dry state of an object to be dried and improve the energy utilization efficiency, and realize a printer that can be downsized, and a printing method capable of producing high-quality printed matter. Is to provide.

  The printer of the present invention is a printer having a droplet discharge head for disposing droplets on an object to be dried, and a microwave generator for generating microwaves and a microwave switching for switching the irradiation path of the microwaves A detection unit that detects a state of the object to be dried before or after printing, a microwave heating unit that heats the droplets disposed on the object to be dried, and the detection unit detects And a control unit for controlling the microwave heating unit based on the result.

  According to the present invention, it is possible to detect the state of the material to be dried before printing and to determine the droplet discharge amount and the feed rate based on the detection result. Similarly, it is possible to detect the post-printing state of the object to be dried and determine the feed rate and the microwave heating amount necessary for drying based on the detection result. Since printing can be performed with the droplet discharge amount, feed rate, and heating amount set to appropriate conditions, a printer capable of performing stable quality printing can be provided.

  In the printer according to the aspect of the invention, the detection unit detects a state of the object to be dried before the droplet is disposed, and detects a state of the object to be dried after the droplet is disposed. It is desirable to provide the 2nd detection part to perform.

  According to this invention, the detection unit is divided into a first detection unit and a second detection unit, the first detection unit detects the state of the body to be dried before printing, and the second detection unit detects the body to be dried. Can detect the post-printing state and determine the droplet discharge amount and the feed speed of the material to be dried based on the respective detection results. Can provide.

  In the printer according to the aspect of the invention, it is preferable that the first detection unit and the second detection unit detect either a dielectric constant or a power ratio of the object to be dried.

  According to this invention, since the first detection unit and the second detection unit can detect the dielectric constant or the power ratio (reflection coefficient) of the object to be dried, before printing and printing included in the object to be dried It is possible to provide a printer that can detect the amount of water later and the material of the object to be dried.

  In the printer of the present invention, the microwave switching unit switches the irradiation position of the microwave to any one of the first detection unit, the microwave heating unit, and the second detection unit, It is desirable to introduce.

  According to the present invention, when irradiating the object to be dried with microwaves, the microwave switching unit switches to any one of the first detection unit, the microwave heating unit, and the second detection unit to emit the microwaves. Since it can be introduced, both detection and heating can be performed, and a single microwave generator can be used, so that a printer that can simplify the configuration of the apparatus can be provided.

  In the printer according to the aspect of the invention, it is preferable that the microwave generation unit generates a microwave using a solid high-frequency oscillator.

  The solid high-frequency oscillator is preferably a surface acoustic wave resonator or dielectric oscillator using diamond or quartz, or an LC oscillator using an inductor or a capacitor.

  According to the present invention, compared to a microwave power source using a vacuum tube such as a magnetron as an oscillation source, a solid high frequency oscillator using a solid high frequency oscillator is used for the microwave power source, so that energy consumed can be reduced. Therefore, the microwave power source can be downsized, and a printer that can be downsized can be provided.

  In the printer according to the aspect of the invention, it is preferable that the microwave heating unit includes a microwave heating mechanism for heating the droplet.

  According to the present invention, since the microwave heating unit includes the microwave heating mechanism for heating the droplets, it is possible to provide a printer that can heat the droplets disposed on the object to be dried.

  The printing method of the present invention is a printing method for forming an image by drying droplets disposed on a material to be dried, the step of generating a microwave from a microwave generator, A detecting step of detecting a reflection intensity of the reflected wave of the irradiated microwave, a droplet arranging step of arranging a droplet on the object to be dried, and irradiating the droplet with the microwave, A heating process for heating and drying and a microwave switching process for switching the irradiation position of the microwave are provided.

  According to the present invention, the state of the object to be dried is detected while switching the irradiation position of the microwave, and based on the detection result, the discharge amount of the droplets and the feed speed of the object to be dried can be determined. Since printing can be performed by setting the amount of droplets and the feed rate to appropriate conditions, printing with stable quality can be performed as a result.

  In the printing method of the present invention, the detection step includes a first detection step of detecting a state of the object to be dried before arranging the droplets, and a state of the object to be dried after arranging the droplets. It is desirable to provide the 2nd detection process to detect.

  According to this invention, the detection process is divided into a first detection process and a second detection process. In the first detection process, the state before printing of the material to be dried is detected, and in the second detection process, The state after printing of the material to be dried can be detected, and the discharge amount of the droplets and the feed speed of the material to be dried can be determined based on the respective detection results, so that more stable quality printing can be performed. it can.

  In the printing method of the present invention, it is desirable that in the first detection step, the first detection unit detects either a dielectric constant or a power ratio of the object to be dried.

  According to this invention, since the 1st detection part can detect the dielectric constant of a to-be-dried body, and a power ratio (reflection coefficient), the moisture content before printing contained in a to-be-dried body, and the to-be-dried body The material can be detected.

  In the printing method of the present invention, in the second detection step, it is preferable that the second detection unit detects either a dielectric constant or a power ratio of the object to be dried.

  According to this invention, since the 2nd detection part can detect the dielectric constant and electric power ratio (reflection coefficient) of a to-be-dried body, it can detect the moisture content after printing contained in a to-be-dried body. It is possible to detect the dry state after printing of the material to be dried.

  In the printing method of the present invention, in the step of switching the microwaves, the microwave switching unit may switch the first detection unit, the microwave heating unit, and the second detection unit in that order. desirable.

  According to this invention, since the microwave switching unit can switch the order of the first detection unit, the microwave heating unit, and the second detection unit to irradiate the object to be dried with microwaves. It can be used effectively.

  In the printing method of the present invention, in the step of generating the microwave, it is preferable that the microwave generator generates the microwave using a solid high-frequency oscillator.

  According to the present invention, compared to a microwave power source using a vacuum tube such as a magnetron as an oscillation source, a solid high-frequency oscillator using a solid high-frequency oscillator is used for the microwave power source, so the accuracy is high and stable. Since oscillation can be realized, printing with good print quality can be performed.

  In the printing method of the present invention, in the heating step, the microwave heating mechanism desirably forms the image by heating and drying the droplets.

  According to this invention, since the microwave heating mechanism can heat the droplets disposed on the object to be dried to form an image, the microwaves can be intensively irradiated onto the droplets. , Can provide stable quality images.

(First embodiment)
Hereinafter, a printer according to the present invention and an embodiment when the printer is used will be described in detail with reference to the accompanying drawings.

  The configuration of the printer will be described. As a printer, an ink jet printer will be described as an example. Although an ink jet printer is used, other printing apparatuses may be used.

  FIG. 1 is a schematic diagram illustrating a configuration of a printer according to the present embodiment.

  As shown in FIG. 1, the printer 1 includes a recording head 2 as a droplet discharge head, a microwave sensor 4 (first microwave sensor 4a and second microwave sensor 4b), and a microwave as a microwave heating unit. The wave heating mechanism 6 and the paper feed roller 21 are roughly configured.

  The recording head 2 has a function of printing on the paper 10 by arranging the droplets 8 on the paper (recording paper) 10 as a material to be dried.

  The microwave sensor 4 includes a first microwave sensor 4a as a first detection unit and a second microwave sensor 4b as a second detection unit. The first microwave sensor 4a is disposed in front of the recording head 2 and has a function of detecting the type of the paper 10 and the surface state before printing. The first microwave sensor 4a is configured to acquire the discharge amount of the droplet 8 and the feed speed of the paper 10 as reference information and store them in the control unit 36 (see FIG. 3). .

  The second microwave sensor 4b is disposed behind the recording head 2 and has a function of detecting the surface state of the paper 10 after printing. And the 2nd microwave sensor 4b is comprised so that the feed speed of the paper 10 can be acquired as reference information, and can be stored in the control part 36 (refer FIG. 3).

  The microwave heating mechanism 6 is disposed behind the second microwave sensor 4b, and can heat the droplet 8 disposed on the paper 10 based on the information acquired by the second microwave sensor 4b. It has a function that can. It should be noted that the conditions such as temperature and speed when the droplet 8 is heated are configured to be controlled by the control unit 36 (see FIG. 3).

  The paper feed roller 21 has a function of feeding the paper 10 in a predetermined direction, and rotates the paper feed roller 21 to feed the paper 10 in the main scanning direction (arrow direction shown in the drawing). A paper feed motor (not shown) is provided in the printer 1. The carriage (not shown) can be mounted with an ink cartridge (not shown), and is mounted on a timing belt (not shown) spanned between a driving pulley (not shown) and an idle pulley (not shown). It is connected. And it is comprised so that the paper 10 can be moved to the main scanning direction (illustration arrow direction) which is the width direction by the drive of a drive pulley (illustration omitted).

  The oscillator 100 as the microwave generation unit has a function of generating the microwave 100a, and the oscillator 100 as the microwave generation unit and the microwave switching unit 550 are connected to each other.

  The microwave switching unit 550 is connected to the first microwave sensor 4 a, the second microwave sensor 4 b, and the microwave heating mechanism 6. A switching function for introducing the microwave 100a into any one of the first microwave sensor 4a, the second microwave sensor 4b, and the microwave heating mechanism 6 is provided. For example, when the microwave switching unit 550 is switched and the microwave 100a is introduced into the microwave heating mechanism 6 to irradiate the paper 10, the droplet 8 disposed on the paper 10 can be heated. Further, the microwave switching unit 550 is switched to introduce the microwave 100a into the first microwave sensor 4a to detect the reflection intensity of the reflected wave 100b (see FIG. 2) reflected from the paper 10, and before the paper 10 is printed. The state of can be detected. Similarly, the microwave switching unit 550 is switched to introduce the microwave into the second microwave sensor 4b to detect the reflection intensity of the reflected wave 100b reflected from the paper 10, thereby detecting the state of the paper 10 after printing. be able to. As a switching method of the microwave switching unit 550 used here, a switching method including a mechanical switching mechanism such as a switch may be adopted. Also, a mechanical switching method is not particular, and a switching method that can be electrically switched may be employed. For example, a system in which the first microwave sensor 4a, the microwave heating mechanism 6, and the second microwave sensor 4b can be switched in this order, and the switching is performed at a predetermined switching timing may be used. In addition, the intensity | strength of the microwave 100a irradiated toward the paper 10 from the 1st microwave sensor 4a, the 2nd microwave sensor 4b, and the microwave heating mechanism 6 may be equal, and may differ.

  FIG. 2 is a block diagram showing an electrical configuration of the heating / detecting mechanism. Note that the first microwave sensor and the second microwave sensor have the same configuration and the same function.

  As shown in FIG. 2, the heating / detecting mechanism 500 can switch the introduction direction of the microwave 100a, an oscillator 100 as a microwave generation unit that oscillates the microwave 100a, an amplifier 120 that amplifies the microwave 100a, and the like. A microwave switching unit 550 that can be used, a control unit 36 that controls the amplifier 120 by obtaining the reflectance from the reflection intensity of the reflected wave 100b, a power monitor 560 as a detection unit, and a circulator 570 that restricts the signal flow direction. The microwave heating mechanism 6, the microwave sensor 4 (the first microwave sensor 4 a and the second microwave sensor 4 b), and the control unit 36 that controls them are roughly configured.

  An oscillator 100 as a microwave generator is a diamond SAW oscillator to which a surface acoustic wave (SAW), which is a solid-state high-frequency oscillator, is applied.

  The amplifier 120 can amplify the microwave 100a by amplifying the signal output from the oscillator 100 and outputting a 2.45 GHz band high-frequency signal. The amplifier 120 and the oscillator 100 are electrically connected.

  The microwave switching unit 550 has a switching function for introducing the signal amplified by the amplifier 120 into the first microwave sensor 4a, the second microwave sensor 4b, and the microwave heating mechanism 6. . In the microwave switching unit 550, the first microwave sensor 4a, the second microwave sensor 4b, and the microwave heating mechanism 6 are electrically connected via a circulator 570 (570a, 570b, 570c). ing.

  The power monitor 560 as a detection unit has a function of detecting the reflection intensity of the reflected wave 100b reflected from the paper 10, and the power monitor 560 (560a, 560b, 560c) as the detection unit, Circulator 570 (570a, 570b, 570c) is electrically connected.

  The circulator 570 (570a, 570b, 570c) supplies each signal amplified by the amplifier 120 to the first microwave sensor 4a, the second microwave sensor 4b, and the microwave heating mechanism 6, and the direction in which the signal flows. It has a function to restrict

  The microwave 100a supplied to the circulator 570a is introduced into the first microwave sensor 4a and has a function of detecting the state of the paper 10 before printing. Similarly, the microwave 100a supplied to the circulator 570b is introduced into the second microwave sensor 4b and has a function of detecting the state of the paper 10 after printing. Furthermore, the microwave 100 a supplied to the circulator 570 c is introduced into the microwave heating mechanism 6 and has a function of heating the droplet 8 disposed on the paper 10.

  Here, the first microwave sensor 4a and the second microwave sensor 4b have the same configuration and the same function. The first microwave sensor 4a (or the second microwave sensor 4b) has a capacitor C. The paper 10 is sandwiched between a pair of electrodes of the first microwave sensor 4a (or the second microwave sensor 4b), and the capacitance between the electrodes depends on the quality of the sandwiched paper 10 and the water content. Change. For this reason, the resonance frequency of the resonance circuit including the capacitor C changes. By detecting the dielectric constant from the changed resonance frequency, the state of the surface of the paper 10 can be detected. The printing process can be optimized by printing with the ink discharge amount and paper feed speed prepared in advance according to the resonance frequency.

  Further, the reflected wave 100b reflected from the paper 10 is configured to be guided to the power monitor 560 (560a, 560b, 560c). Then, the reflected wave 100b guided to the power monitor 560 (560a, 560b, 560c) is guided to the control unit 36, and the control unit 36 controls the amplifier 120 and the microwave switching unit 550 according to the degree of the reflection intensity of the reflected wave 100b. Configured to control.

  FIG. 3 is a block diagram showing the electrical configuration of the printer.

  As shown in FIG. 3, the printer 1 is schematically configured by a printer controller 31 and a print engine 32. A control unit 36 included in the printer controller 31 is configured to be able to perform control of the printer 1 and control of the heating / detecting mechanism 500 (see FIG. 2).

  The printer controller 31 generates an I / F (interface) 33, a RAM (Random Access Memory) 34, a ROM (Read Only Memory) 35, a control unit 36 including a CPU (Central Processing Unit), and the like, and generates a clock signal. The oscillation circuit 37, the drive signal generation circuit 3, and the I / F (interface) 38 are provided.

  The I / F 33 can receive, for example, print data including any one or more of character code, graphic code, and image data from a host computer (not shown). The I / F 33 can output a busy signal, an acknowledge signal, and the like to the host computer.

  The RAM 34 has a function of storing various data and is used as a reception buffer, an intermediate buffer, an output buffer, a work memory (not shown), and the like. Print data from the host computer received by the I / F 33 is temporarily stored in the reception buffer. In the intermediate buffer, intermediate code data converted into an intermediate code by the control unit 36 is stored. Print data for each dot is developed in the output buffer.

  The ROM 35 has a function of storing various control routines executed by the control unit 36, font data and graphic functions, various procedures, and the like.

  The control unit 36 reads the print data in the reception buffer, converts it into an intermediate code, and stores this intermediate code data in the intermediate buffer. The control unit 36 has a function of analyzing the intermediate code data read from the intermediate buffer and developing the intermediate code data into print data by referring to the font data and graphic functions in the ROM 35. This print data is composed of, for example, 2-bit gradation information. The expanded print data is stored in the output buffer, and when print data corresponding to one line of the recording head 2 is obtained, the print data for one line is stored in the recording head 2 via the I / F 38. Serially transmitted. When one line of print data is transmitted from the output buffer, the contents of the intermediate buffer are erased and conversion to the next intermediate code is performed. The control unit 36 constitutes a part of the timing signal generating means. It has a function of supplying a latch signal and a channel signal to the recording head 2 through the I / F 38. These latch signals and channel signals have a function of defining the supply start timing of each pulse signal constituting the drive signal. The control unit 36 has a CPU (not shown) installed therein, a function for judging paper information, a function for controlling printing, a function for controlling the paper feed speed, a function for controlling the dry state, and a microwave. It has functions such as switching control.

  The drive signal generation circuit 3 is a kind of drive signal generation means, and has a function of generating a series of drive signals including a drive pulse composed of a plurality of waveform elements and supplying these drive signals to the recording head 2. ing.

  The I / F (interface) 38 has a function of transmitting print data developed in dot pattern data, drive signals, and the like to the print engine 32.

  The print engine 32 includes an electric drive system of the recording head 2 and a paper feed motor 39 that rotates the paper feed roller 21 (see FIG. 1).

  The electric drive system of the recording head 2 includes a shift register circuit including a first shift register 41 and a second shift register 42, a latch circuit including a first latch circuit 43 and a second latch circuit 44, a decoder 45, and control logic. 46, a level shifter 47, a switch circuit 48, and a piezoelectric vibrator 15 are provided.

  The heating / detecting mechanism 500 in this embodiment is mounted on the printer 1 shown in FIG.

  Next, the configuration of the microwave heating mechanism will be described. There are three types of microwave heating mechanisms depending on the model, and each will be described with reference to the drawings. In addition, since microwaves are irradiated using an antenna, the antenna configuration can uniformly irradiate the same width as the head of the droplet discharge head and has a single directivity in the paper direction (irradiation direction). Is preferred. In addition, it is preferable to have a structure that includes a reflector that reflects microwaves that leak in directions other than the direction of the paper.

  (First type microwave heating mechanism)

  FIG. 4 is a schematic view showing the configuration of the microwave heating mechanism.

  As shown in FIG. 4, the first type microwave heating mechanism 60 is equipped with a patch array type antenna, and is generated from an oscillator 100 (see FIGS. 1 and 2) as a microwave generation unit. The microwave 100a can be radiated from a radiation pattern H as an antenna. The microwave 100a radiated from the radiation pattern H is configured to be focused by being reflected directly or by a reflector 67 as a reflector. Here, in the radiation pattern H, five patch antennas H1 to H5 are arranged in an array. The length of one side of the patch antenna is preferably ¼ of the wavelength λ of the microwave used. Further, the length may be 1 / (4N) λ (N is a positive integer) such as 1 / 8λ, 1 / 16λ, and the like. In this way, the phases of the microwaves 100a fed to the respective patch arrays can be made uniform, so that the microwaves 100a can be irradiated uniformly.

(2nd type microwave heating mechanism)
Next, the configuration of the second type microwave heating mechanism will be described.

  FIG. 5 is a schematic diagram showing the configuration of the microwave heating mechanism.

  As shown in FIG. 5, the second type microwave heating mechanism 70 is equipped with a coaxial leaky antenna 78 and is disposed on the fixed shaft 21 a via a support member 75. The support member 75 includes a reflector 76 as a reflector that reflects the microwave 100 a, and shielding plates 77 are disposed at both ends of the reflector 76 on the short side. A coaxial leaky antenna 78 is disposed in the center of the reflector 76 via a support member 75.

  The coaxial leaky antenna 78 includes a metal core 79 at the center thereof. The core wire 79 includes a part that is partially exposed and a part that is covered with a coating, and these are repeated. The exposed length La where the core wire 79 is exposed is preferably the wavelength λ of the radiating microwave 100a. It is also preferable that the phases of the leaking microwave 100a are aligned.

  In the portion covered with the film, a dielectric layer 71 made of a dielectric is formed on the outer periphery of the core wire 79. A metal ground layer 72 is formed on the outer periphery of the dielectric layer 71, and the ground layer 72 is electrically grounded. A protective layer 73 is formed on the outer periphery of the ground layer 72 and is configured to electrically insulate the ground layer 72.

(3rd type microwave heating mechanism)
Next, the configuration of the third type microwave heating mechanism will be described.

  FIG. 6 is a schematic diagram showing the configuration of the microwave heating mechanism.

  As shown in FIG. 6, the third type microwave heating mechanism 80 has a plurality of coaxial leaky antennas 83 and 84 mounted thereon, and the coaxial leaky antennas 83 and 84 are arranged in the longitudinal direction of the paper 10. Thus, the microwave 100a can be collectively irradiated onto the entire sheet. In this way, the microwave 100a can be irradiated evenly on the paper 10, so that heating and drying with little unevenness can be performed.

  The coaxial leaky antennas 83 and 84 have a metal core wire arranged at the center, and a dielectric layer made of a dielectric, a ground layer made of metal, and a coating made of an insulator are arranged concentrically around the outer periphery thereof. ing. The ground layer is electrically grounded, and is configured such that even if the microwave 100a is radiated from the core wire, it is not radiated from a portion of the ground layer.

  The coaxial leaky antennas 83 and 84 are arranged so that the exposed positions of the core wires are different, and are configured to irradiate the microwave 100a to different positions of the paper 10 that travels. The range in which the coaxial antenna 83 irradiates the microwave 100a and the range in which the coaxial antenna 84 irradiates the microwave 100a are combined so that the entire paper 10 can be irradiated.

  A reflector 85 as a reflector is disposed on the opposite side of the paper 10, and the microwave 100a is radiated from the coaxial leaky antennas 83 and 84, and the microwave 100a reaching the reflector 85 changes its traveling direction. , The paper 10 is advanced.

  Next, the operation of the printer will be described.

  FIG. 7 is a flowchart showing the operation procedure of the printer in this embodiment. In addition, as the microwave heating mechanism for heating the droplet, any one of the first to third types of microwave heating mechanisms is employed to heat the droplet. Here, the case where the 1st type microwave heating mechanism shown in FIG. 4 is employ | adopted is demonstrated. The description will be made with reference to the heating / detecting mechanism of FIG.

  In step S1 of FIG. 7, the emission of the microwave 100a is started. The oscillator 100 as the microwave generation unit generates a high-frequency signal and starts emitting the microwave 100a.

  In step S2 of FIG. 7, the microwave 100a is amplified. The microwave 100a is amplified by an amplifier 120 as an amplifier.

  In step S3 of FIG. 7, the microwave 100a is emitted. The microwave 100a output from the amplifier 120 is radiated after the introduction direction is switched by the microwave switching unit 550. The emitted microwave 100a is guided to the first microwave sensor 4a via the circulator 570a.

  In step S4 of FIG. 7, the dielectric constant of the paper 10 is detected. As a method for detecting the dielectric constant of the paper 10, for example, a resonance method is used. Of the microwave 100a guided to the first microwave sensor 4a, the reflected wave 100b reflected by the impedance mismatch is transmitted to the other end of the circulator 570a, and a power monitor as a detection unit that detects the reflected wave 100b. To 560a. In general, when the reflected wave 100b returns to the amplifier 120, there is a possibility that the amplifier circuit may be destroyed. Therefore, the circulator 570a is often inserted as a protection circuit. The emitted microwave 100a is a substantially plane wave, and is emitted from the front surface of the paper 10 inserted between the pair of electrodes of the first microwave sensor 4a toward the back surface. Therefore, since the capacitance value C of the capacitor C changes according to the moisture content of the paper 10 existing between the capacitors C, the resonance frequency f = 1 / 2π√ (LC) of the resonance circuit changes. The difference between the resonance frequency f1 when paper is present between the capacitors C and the resonance frequency f0 measured in advance when paper is not present between the capacitors C is correlated with the dielectric constant of the paper. Therefore, the dielectric constant of the paper can be known by measuring f1. Using the method of detecting the dielectric constant, the material and surface state of the paper 10 before printing are detected. If the correspondence data between the moisture content and the dielectric constant for each type of paper 10 is prepared in advance, the material and moisture content of the paper 10 can be calculated from the obtained dielectric constant.

  In step S5 in FIG. 7, the amount of ink corresponding to the state of the paper 10 is determined. When the moisture content of the paper 10 decreases and the reflection intensity of the reflected wave 100b increases, the amount of ink in the droplet 8 to be arranged is increased. Conversely, when the reflection intensity of the reflected wave 100b is decreasing, the amount of ink in the droplet 8 to be arranged is reduced. The operation of determining the state of the paper and controlling the amount of ink to be arranged is performed by the control unit 36 (see FIG. 3). It is desirable that the detection operation for detecting the intensity of the reflected wave 100b is always performed during the operation of the printer 1 shown in FIG. By always performing this detection operation, a more accurate detection result can be obtained.

  In step S6 of FIG. 7, printing is performed. The printing method can be performed by ejecting ink from the recording head 2 (see FIG. 1) toward the paper 10 and disposing the droplets 8 on the paper 10. The amount of ink in the droplet 8 to be arranged corresponds to the amount obtained in step S5. The ink used here is for printing (including printing) on the paper 10. For example, when printing in six colors, cyan, light cyan, magenta, light magenta, yellow And those having a pigment such as black.

  In step S7 of FIG. 7, the dielectric constant of the paper 10 is detected. Since the method for detecting the dielectric constant of the paper 10 is the same as the method implemented in step S4, the description thereof is omitted. However, here, the microwave 100a is switched by the microwave switching unit 550, and the microwave 100a is introduced into the second microwave sensor 4b. The microwave 100a is introduced through the circulator 570b. Then, the surface state of the paper 10 after printing is detected. In addition, it is convenient to select the conditions for drying if the correspondence data of the moisture content and the dielectric constant for each type of frequently used paper (printing paper) 10 is prepared in advance.

  In step S8 of FIG. 7, it is determined whether heating and drying are necessary. This determination method is determined by the control unit 36 based on the result of detecting the surface state of the paper 10 after printing in step S7. If the operation of heating / drying the droplet 8 placed on the paper 10 is necessary, the process proceeds to the next step S9, and if not necessary, the process proceeds to step S11 for stopping the emission of microwaves.

  In step S9 in FIG. 7, the irradiation amount of the microwave 100a corresponding to the dry state and the paper feed speed are determined. In this determination method, the data of the dielectric constant of the paper 10 detected in step S7 is sent to the control unit 36, and a CPU (not shown) mounted on the control unit 36 allows the irradiation amount of the microwave 100a and after printing. The paper feed speed is calculated and determined. More specifically, when the amount of water contained in the paper 10 is large, heating is performed more strongly by increasing the irradiation amount of the microwave 100a than when the amount of water is small. Further, when the amount of water contained in the paper 10 is large, the control unit 36 controls the printer 1 (see FIG. 1) so as to make the paper feeding speed slower than when the amount of water is small.

  In step S10 of FIG. 7, heating and drying are performed. This heating / drying method uses a microwave heating mechanism 6 (see FIG. 1) to irradiate a microwave 100a on the paper 10 and heat the droplets 8 arranged on the paper 10 to dry the paper. Do. Here, it is carried out based on conditions such as the predetermined paper feed speed and heating time obtained in step S9.

  In step S11 of FIG. 7, the microwave irradiation is stopped. When heating / drying of the droplet 8 is completed, the oscillation of the high-frequency signal oscillated from the oscillator 100 serving as the microwave generator is stopped, and the operation is completed.

According to the printer configuration and the printing method in the first embodiment as described above, the following effects can be obtained.
(1) The state of the paper 10 before printing can be detected, and the ejection amount of the droplets 8 and the feeding speed of the paper 10 can be determined based on the detection result. Similarly, the state after printing of the paper 10 can be detected, and the feeding speed of the paper 10 can be determined based on the detection result. Since the heating / drying conditions can be determined by controlling the microwave heating mechanism 6 as the microwave heating unit, the discharge amount of the droplets 8 and the feeding speed of the paper 10 are set to appropriate conditions. As a result, it is possible to provide the printer 1 capable of performing stable quality printing.
(2) The microwave sensor 4 as a detection unit is divided into a first microwave sensor 4a as a first detection unit and a second microwave sensor 4b as a second detection unit, and the first microwave sensor 4a detects the state of the paper 10 before printing, and the second microwave sensor 4b detects the state of the paper 10 after printing. Based on the respective detection results, the ejection amount of the droplets 8 and the paper 10 Since the feed speed can be determined, the printer 1 capable of performing more stable quality printing can be provided.
(3) Since the first microwave sensor 4a can detect the dielectric constant of the paper 10, if the dielectric constant of the paper 10 is detected, the amount of moisture contained before the printing of the paper 10 can be detected. . By detecting the state of the paper 10 before printing and using the detected information, it is possible to optimize the printing process in terms of the ejection amount of the droplets 8 and the printing speed. As a result, it is possible to provide the printer 1 capable of reducing print quality and materials used.
(4) Since the second microwave sensor 4b can detect the dielectric constant of the paper 10, if the dielectric constant of the paper 10 is detected, the amount of water contained after the printing of the paper 10 can be detected. By detecting the dry state of the droplets 8 after printing and using the detected information for the determination of the heating amount and the conveyance speed, the drying process can be optimized. As a result, it is possible to provide the printer 1 that can improve the printing quality, shorten the entire printing process, and reduce the energy used.
(5) When irradiating the paper 10 with the microwave 100a, the microwave switching unit 550 applies the microwave to any one of the first microwave sensor 4a, the microwave heating mechanism 6, and the second microwave sensor 4b. Since the microwave 100a can be introduced after switching the switching unit 550, both detection and heating can be performed, and the oscillator 100 as the microwave generation unit can be combined into one, so that the configuration of the apparatus Can be provided.
(6) Compared with a microwave power source using a vacuum tube such as a magnetron as an oscillation source, a solid-state high-frequency oscillator using a diamond surface acoustic wave oscillator is used as an oscillator 100 as a microwave generation unit as a microwave power source. Therefore, since the microwave power source can be reduced in size, it is possible to provide the printer 1 that can be reduced in size. Furthermore, since a solid-state high-frequency oscillator such as a diamond SAW oscillator is used, power saving and high-efficiency excitation are possible, so that energy consumption can be suppressed. If energy consumption can be suppressed, it can also contribute to reduction of environmental load.
(7) Since the microwave heating mechanism 6 (60, 70, 80) serving as the microwave heating unit for heating the droplet 8 is provided, the droplet 8 arranged on the paper 10 can be heated. The printer 1 can be provided.
(8) Since the antenna 78 (83, 84, H) for irradiating the microwave 100a and the reflector 67 (76, 85) as a reflector for reflecting or concentrating the microwave 100a are provided, the microwave 100a is provided. Therefore, it is possible to provide the printer 1 capable of more efficiently performing the operation when heating the droplets 8 arranged on the paper 10.

(Second Embodiment)
In this embodiment, a printer equipped with a heating / detecting mechanism having a configuration different from that of the first embodiment will be described.

  FIG. 8 is a block diagram showing an electrical configuration of the heating / detecting mechanism in the second embodiment. FIG. 9 is a flowchart showing the operation procedure of the printer. In the present embodiment, the difference from the first embodiment described above is not to detect the resonance frequency but to detect the reflection coefficient, and the configuration of the detection unit is different. The same parts as those in the first embodiment described above and parts having the same functions are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 8, the heating / detecting mechanism 501 switches the oscillator 100 as a microwave generator that oscillates the microwave 100a, the amplifier 120 that amplifies the microwave 100a, and the direction in which the microwave 100a is introduced. A microwave switching unit 550 capable of controlling the amplifier 120 by obtaining the reflectance from the reflection intensity of the reflected wave 100b, a power monitor 560 as a detection unit, and a circulator 570 for limiting the direction of signal flow. And a microwave heating mechanism 6, a control unit 36 for controlling them, and a microwave sensor 5 (first microwave sensor 5a and second microwave sensor 5b).

  In FIG. 8, since the first microwave sensor 5a and the second microwave sensor 5b have the same configuration and the same function, the first microwave sensor 5a will be described here. The first microwave sensor 5a includes a first power measurement unit 581a and is connected to a power monitor 560a. The first power measuring unit 581a has a function of detecting and measuring the power of the microwave 100a introduced from the microwave switching unit 550. Similarly, the power monitor 560a has a function of detecting and measuring the power of the reflected wave 100b. By calculating the ratio of the power detected by the first power measuring unit 581a and the power monitor 560a by the control unit 36, the reflection coefficient (S11) can be measured. Since the absorption of the microwave 100a changes according to the quality of the object to be dried and the surface state, the reflection coefficient of the antenna also changes. Depending on the reflection coefficient, printing can be performed at an ink discharge amount and paper feed speed prepared in advance, so that the printing process and the heating process can be optimized.

  The heating / detecting mechanism 501 in this embodiment is mounted on the printer 1 shown in FIG.

  Next, the operation of the printer will be described.

  FIG. 9 is a flowchart showing the operation procedure of the printer in this embodiment. In addition, as the microwave heating mechanism for heating the droplet, any one of the first to third types of microwave heating mechanisms is employed to heat the droplet. Here, the case where the 1st type microwave heating mechanism shown in FIG. 4 is employ | adopted is demonstrated. The description will be made with reference to the heating / detecting mechanism of FIG.

  Steps S1 to S3, S5, S6, and S8 to S11 in FIG. 9 are the same as Steps S1 to S3, S5, S6, and S8 to S11 in FIG. 7, and thus description thereof is omitted. Here, Steps S4 and S7 are omitted. Will be described.

  In step S4 of FIG. 9, the reflectance of the paper 10 is detected. The paper 10 is in a state before printing and the droplets 8 are not arranged. As a method for detecting the reflectance of the paper 10, the power of the microwave 100a guided to the first microwave sensor 5a via the first power measuring unit 581a is measured in advance. The reflected wave 100b that has been reflected is transmitted to the other end of the circulator 570a and guided to a power monitor 560a that serves as a detection unit that detects the reflected wave 100b. The power of the reflected wave 100b is measured in advance. The reflection intensity of the reflected wave 100b varies depending on the reflectance of the paper 10. This reflectance is a power ratio (reflection coefficient), and the surface state of the paper 10 before printing is detected using a method of detecting this power ratio.

  In step S7 of FIG. 9, the reflectance of the paper 10 is detected. The paper 10 is after printing and in a state where the droplets 8 are arranged. Note that the method of detecting the reflectance of the paper 10 is the same as the method performed in step S4, and thus the description thereof is omitted. However, here, the microwave 100a is switched by the microwave switching unit 550, and the microwave 100a is introduced into the second microwave sensor 5b. The microwave 100a is introduced through the circulator 570b. Then, the surface state of the paper 10 after printing is detected.

According to the printer configuration and the printing method in the second embodiment as described above, the following effects can be obtained in addition to the effects obtained in the first embodiment.
(9) Since the first microwave sensor 5a can detect the power ratio (reflection coefficient) of the paper 10, the droplet 8 is detected by detecting the state of the paper 10 before printing and using the detected information. It is possible to optimize the printing process in terms of the discharge amount and printing speed. As a result, it is possible to provide the printer 1 capable of reducing print quality and materials used.
(10) Since the second microwave sensor 5b can detect the power ratio (reflection coefficient) of the paper 10, the dried state of the droplet 8 after printing is detected, and the detected information is used for the heating amount and the conveyance speed. It is possible to optimize the drying process by using this for the determination. As a result, it is possible to provide the printer 1 that can improve the printing quality, shorten the entire printing process, and reduce the energy used.

  As described above, the present invention has been described with reference to preferred embodiments, but the present invention is not limited to the above-described embodiments, and includes modifications as described below, as long as the object of the present invention can be achieved. It can be set to any other specific structure and shape.

(Modification 1)
In the first embodiment and the second embodiment described above, one microwave heating mechanism 6 is mounted. However, the present invention is not limited to this. For example, a configuration may be adopted in which two microwave heating mechanisms 6 are mounted by adding the microwave heating mechanism 6 after the first microwave sensor 4a. That is, the first microwave sensor 4a, the microwave heating mechanism 6 (added), the recording head 2 as a droplet discharge head, the second microwave sensor 4b, and the microwave heating mechanism 6 may be configured in this order. In this way, since the paper 10 before printing can be heated and dried using the added microwave heating mechanism 6, it can be expected that the paper quality of the paper 10 before printing is further stabilized. Therefore, it can be expected to provide the printer 1 that can further improve the printing quality.

(Modification 2)
In the first and second embodiments described above, the first microwave sensor 4a (or the first microwave sensor 5a) and the second microwave sensor 4b (or the second microwave sensor 5b) are connected to the printer 1. However, the present invention is not limited to this. For example, one of the first microwave sensor 4a (or the first microwave sensor 5a) and the second microwave sensor 4b (or the second microwave sensor 5b) is configured to be mounted on the printer 1. Also good. In this way, the number of components can be reduced, so that an inexpensive printer 1 can be provided.

FIG. 2 is a schematic diagram illustrating a configuration of a printer according to the first embodiment. The block diagram which shows the electric constitution of a heating and a detection mechanism. FIG. 2 is a block diagram illustrating an electrical configuration of the printer. Schematic which shows the structure of a heating mechanism. Schematic which shows the structure of a heating mechanism. Schematic which shows the structure of a heating mechanism. 6 is a flowchart illustrating an operation procedure of the printer. The block diagram which shows the electric constitution of the heating and the detection mechanism in 2nd Embodiment. 6 is a flowchart illustrating an operation procedure of the printer.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Printer, 2 ... Recording head as droplet discharge head, 4 ... Microwave sensor as detection part, 4a ... 1st microwave sensor as 1st detection part, 4b ... 2nd micro as 2nd detection part A microwave sensor, 5 ... a microwave sensor, 5a ... a first microwave sensor as a first detector, 5b ... a second microwave sensor as a second detector, 6 ... a microwave heating mechanism as a microwave heater, 8 ... droplets, 10 ... paper as a material to be dried, 36 ... control unit, 60 ... microwave heating mechanism as microwave heating unit, 70 ... microwave heating mechanism as microwave heating unit, 76 ... as reflector Reflector, 77 ... shielding plate, 78 ... coaxial leakage antenna, 80 ... microwave heating mechanism as a microwave heating unit, 83 ... coaxial leakage antenna, 84 ... coaxial leakage antenna, 5 ... Reflector as reflector, 100 ... Oscillator as microwave generation unit, 100a ... Microwave, 100b ... Reflected wave, 500 ... Heating / detection mechanism, 501 ... Heating / detection mechanism, 550 ... Microwave switching unit, H ... Radiation pattern as an antenna.

Claims (13)

A printer having a droplet discharge head for disposing droplets on an object to be dried,
A microwave generator for generating microwaves;
A microwave switching unit for switching the microwave irradiation path;
A detection unit for detecting a state of the dried body before printing or after printing;
A microwave heating unit that heats the droplets disposed on the object to be dried;
A printer comprising: a control unit that controls the microwave heating unit based on a result detected by the detection unit. The printer according to claim 1.
A first detection unit that detects a state of the object to be dried before arranging the droplet; a second detection unit that detects a state of the object to be dried after arranging the droplet; The
A printer characterized by comprising. The printer according to claim 1 or 2,
The printer, wherein the first detection unit and the second detection unit detect either a dielectric constant or a power ratio of the object to be dried. The printer according to claim 1.
The microwave switching unit switches the irradiation position of the microwave to any one of the first detection unit, the microwave heating unit, and the second detection unit, and introduces the microwave. Printer. The printer according to claim 1.
The printer, wherein the microwave generation unit generates a microwave using a solid high-frequency oscillator. The printer according to claim 1.
The printer, wherein the microwave heating unit includes a microwave heating mechanism for heating the droplets. A printing method for forming an image by drying droplets disposed on an object to be dried,
A step of generating a microwave from the microwave generation unit;
A detection step of detecting a reflection intensity of the reflected wave of the microwave irradiated to the object to be dried;
A droplet placement step of placing droplets on the object to be dried;
A heating step of irradiating the droplet with the microwave and heating and drying the droplet;
A microwave switching step of switching the microwave irradiation path,
A printing method comprising: The printing method according to claim 7,
The detection step includes a first detection step for detecting a state of the object to be dried before arranging the droplet, and a second detection step for detecting a state of the object to be dried after arranging the droplet. The
A printing method comprising: The printing method according to claim 7 or 8,
In the first detection step,
The printing method, wherein the first detection unit detects either a dielectric constant or a power ratio of the object to be dried. The printing method according to claim 7 or 8,
In the second detection step,
The printing method, wherein the second detection unit detects either a dielectric constant or a power ratio of the object to be dried. The printing method according to claim 7,
In the microwave switching step,
The printing method, wherein the microwave switching unit switches the first detection unit, the microwave heating unit, and the second detection unit in that order. The printing method according to claim 7,
In the step of generating the microwave,
The printing method, wherein the microwave generation unit generates the microwave using a solid high-frequency oscillator. The printing method according to claim 7,
In the heating step,
The printing method, wherein the microwave heating mechanism heats and drys the droplets to form the image.

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