JP2008155482A - Image printer and control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve a precision for discriminating a type of a recording material, and to reduce a time required for discrimination. <P>SOLUTION: The image printer includes: a detector for detecting at least one parameter representing a nature for every recording material; a first discriminating part for discriminating a type of a recording material from each parameter detected through a first detection process by the detector, by using a discrimination table in which a corresponding relationship between each parameter and a type of a recording material are registered; a first determination part for determining, when a discrimination target recording material is the second and later recording material in the same print job, whether the type of the previous recording material and that of the present recording material, discriminated by the first discrimination part are the same; and a second discriminating part which makes, when the type of the previous recording material and that of the present recording material are different from each other, the detector execute a plurality of detection processes while making the detector change a detection position in the recording material surface, and discriminates the type of the recording material from an average value of the obtained respective parameters and the discrimination table. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image printing apparatus that determines the type of a recording material in order to determine printing conditions.

  2. Description of the Related Art Conventionally, an image printing apparatus determines printing conditions such as a recording material conveyance condition, a transfer condition, and a fixing condition according to, for example, a recording material size and type (hereinafter referred to as a type) set by an operator. is doing. There is also known an image printing apparatus that uses a sensor that internally determines the type of recording material to determine printing conditions according to the determined type.

Patent Document 1 discloses an image printing apparatus that discriminates between a gloss film having high glossiness and plain paper having low glossiness by emitting light from a light emitting element to a recording material and receiving reflected light reflected by the recording material. Is shown. Patent Document 2 shows an image printing apparatus that determines the thickness of a recording material by emitting light from a light emitting element to the recording material and receiving transmitted light that has passed through the recording material.
Japanese Patent Laid-Open No. 02-138805 JP 2001-139189 A

  However, in recent years, the types of recording materials have increased, and it has become difficult to distinguish between similar types of recording materials. This is because the difference between the values obtained by the light receiving sensors from different types of recording materials is too small. Due to variations in the surface roughness, thickness, etc. of the recording material itself, the detected value may vary even within the same recording material surface and may be erroneously determined.

  Therefore, in order to improve the discrimination accuracy of the recording material, the detection position is moved within the surface of the same recording material, and the average value of the detection results obtained by performing a plurality of detection operations is used. It is thought that the other can be reduced (related technology).

  However, the related art image printing apparatus described above has a problem in throughput during printing because the detection operation is repeated a plurality of times. The detection operation is performed with the recording material stopped in order to stabilize the posture of the recording material. Therefore, if a plurality of detection operations are performed, it is necessary to stop the recording material each time the detection position is moved. For example, it is assumed that it takes about 800 ms to perform one detection operation. If the number of detections of the recording material is N times, the time required for a plurality of detection operations is about 800 × Nms. Therefore, the discrimination accuracy for discriminating the type of recording material is improved, but printing with high throughput is difficult.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an image printing apparatus that improves the discrimination accuracy of the type of recording material while suppressing an increase in the time required for the discrimination process. .

  The present invention can be realized as an image printing apparatus, for example. The image printing apparatus includes a detection unit that detects one or more parameters representing properties for each recording material. In addition, the image printing apparatus uses the determination table in which the correspondence relationship between each parameter and the recording material type is registered to determine the recording material type from each parameter detected by one detection process by the detection unit. 1 discrimination part is included. In addition, when the recording material to be discriminated is the second or subsequent recording material in the same print job, the image printing apparatus determines the type of the previous recording material and the current discriminated by the first discriminating unit. A first determination unit that determines whether or not the type of the recording material is the same. When it is determined that the type of the previous recording material is different from the type of the current recording material, the image printing apparatus performs detection processing multiple times by the detection unit while moving the detection position within the surface of the recording material. And a second discriminating unit for discriminating the type of the recording material from the obtained average value of each parameter and the discrimination table.

  The present invention can provide an image printing apparatus that can improve the discrimination accuracy of the type of recording material while suppressing an increase in the time required for the discrimination process.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings. The following embodiments do not limit the invention described in the claims, and all the combinations of features described in the embodiments are essential to the solution means of the present invention. Not exclusively. The present invention is realized by an electrophotographic image printing apparatus as an application example. However, the present invention may be realized by an image printing apparatus that employs another image printing method such as an inkjet printer.

[First Embodiment]
The first embodiment will be described below with reference to FIGS. 1 to 11. FIG. 1 is a cross-sectional view illustrating an example of an image printing apparatus corresponding to the first embodiment. Here, only the main elements related to the present invention will be described.

  The image printing apparatus 100 includes a recording material discrimination sensor 101, a conveyance path 102, image forming units 103a, b, c, and d, a fixing unit 104, recording material cassettes 105 and 106, and a multi-tray 107. Further, the image printing apparatus 100 includes rollers for transporting the recording material along the transport path 102.

  The recording material discrimination sensor 101 irradiates light onto the surface of the recording material supplied from the recording material cassettes 105 and 106 and the multi-tray 107, and detects the regular reflection light amount and the irregular reflection light amount at that time. Therefore, it is desirable that the recording material discrimination sensor 101 is arranged at a position where the recording materials supplied from the recording material cassettes 105 and 106 and the multi-tray 107 join. Further, the recording material discrimination sensor 101 irradiates light on the back surface of the recording material from a slit formed in the conveyance path, and detects the normal transmitted light amount at that time. As a result, the image printing apparatus 100 detects the property of each supplied recording material in the print job. A specific description of the recording material discrimination sensor 101 will be described later with reference to FIG.

  The image forming units 103a, 103b, 103c, and 103d form developer images on the conveyed recording material. The image forming units 103a, 103b, 103d, and 103d respectively include black, cyan, magenta, and yellow developers. Specifically, each of the image forming units 103a, 103b, 103c, and 103d includes a photosensitive drum, a developing device, an exposure device, and a transfer roller. Briefly, when forming an image on a recording material, each of the image forming units 103 (103a to 103d) first forms an electrostatic latent image on the photosensitive drum by the exposure device and develops it by the developing device. . Thereafter, each image forming unit 103 transfers the developer image formed on the photosensitive drum to the recording material by nipping and conveying the recording material conveyed by the photosensitive drum and the transfer roller.

  The fixing unit 104 fixes the developer image formed by each image forming unit 103 on the recording material. Specifically, the fixing unit 104 fixes the developer image on the recording material to the recording material by applying pressure and heating. Thereafter, the recording material on which the developer image is fixed is discharged out of the apparatus.

  The recording material cassettes 105 and 106 stack recording materials and supply the recording material designated in the print job to the conveyance path 102. In addition, a recording material having a size or property different from a standard size such as A4 or B5 is manually inserted into the multi-tray 107. As described above, the image printing apparatus 100 can handle recording materials having various properties.

  FIG. 2 is a diagram illustrating an example of a recording material discrimination sensor corresponding to the first embodiment. As shown in FIG. 2, the recording material discrimination sensor 101 includes an LED 201 that is a light emitting element and phototransistors 202 and 203 that are light receiving elements, which are arranged on the upper side of the conveyance path 102. Further, the recording material discrimination sensor 101 includes an LED 204 that is a light emitting element disposed below the conveyance path 102. Therefore, the conveyance path 102 is provided with a window 209 for irradiating light from the back side of the recording material.

  Light using the LED 201 as a light source is applied to the surface of the recording material 208 on the conveyance path 102 through the slit 206a. The reflected light from the recording material 208 is collected through the slits 206 b and 206 c and received by the phototransistors 202 and 203. Thus, the glossiness for determining the surface roughness of the recording material 208 is detected.

  Light using the LED 204 as a light source is applied to the back surface of the recording material 208 through a light collecting guide 207 formed to collect the light. The transmitted light from the recording material 208 is received by the phototransistors 202 and 203 through the slits 206b and 206c. Thereby, the transmittance for determining the thickness of the recording material 208 is detected.

  According to the present embodiment, the LED 201 is arranged so that the light to be irradiated is irradiated obliquely with a predetermined angle as shown in FIG. 2 with respect to the surface of the recording material 208. Further, the LED 204 is arranged so that the irradiated light is irradiated from the position directly below the phototransistor 202 to the back surface of the recording material 208 as shown in FIG.

  As described above, the image printing apparatus 100 according to the present embodiment uses the recording material determination sensor 101 to detect one or more parameters representing the properties of the recording material, for example, glossiness and transparency. The image printing apparatus 100 uses these one or more parameters to determine the type of recording material, for example, plain paper, cardboard, glossy paper, and the like. The determined type of recording material is used to determine printing conditions such as recording material conveyance conditions, transfer conditions, and fixing conditions.

  FIG. 3 is a diagram illustrating an example of a control configuration in the image printing apparatus corresponding to the first embodiment. Here, only the control configuration relating to the present invention will be described. That is, the control configuration of the image printing apparatus according to the present invention is not limited to the configuration described below.

  The image printing apparatus 100 includes a control device 301 shown in FIG. The control device 301 includes a main control unit 302, a light emitting element driving unit 306, a detection unit 307, a determination unit 308, an average value calculation unit 309, and a memory 310. The main control unit 302 includes a determination unit 303, a determination unit 304, and an inquiry unit 305 for controlling the light emitting element driving unit 306 and determining printing conditions according to the determined type of recording material. The control device 301 controls the recording material cassettes 105 and 106, the multi-tray 107, the image forming units 103, the fixing unit 104, the transport mechanism unit 311 that is each roller, and a display operation panel 312 (not shown) shown in FIG. To do. The display / operation panel 312 notifies the operator of the state of the image printing apparatus 100, for example, during operation or occurrence of a jam. The display operation panel 312 has an input mechanism, and accepts setting of printing conditions from the operator.

  The light emitting element driving unit 306 drives the LEDs (light emitting elements) 201 and 204 in accordance with instructions from the main control unit 302. The detection unit 307 performs A / D conversion on output values from the phototransistors (light receiving elements) 202 and 203 that receive reflected light and transmitted light with a resolution of 16 bits, and sets one or more parameters representing the properties of each recording material. To detect. For example, the detection unit 307 obtains a parameter indicating the glossiness (regular reflection light amount / diffuse reflection light amount) of the recording material. However, the regular reflection light amount is an output of the phototransistor 203 when only the LED 201 emits light, and the irregular reflection light amount is an output of the phototransistor 202 when only the LED 204 emits light. Further, the detection unit 307 obtains a regular transmitted light amount indicating the transmittance of the recording material. However, the normal transmitted light amount is an output of the phototransistor 202 when only the LED 204 emits light.

  The determination unit 308 determines the type of the recording material using each parameter detected by the detection unit 307 and the determination table. Here, the discrimination table indicates, for example, a table in which the correspondence relationship between each parameter stored in advance in the memory 310 and the type of recording material is registered. Details of the determination table will be described later with reference to FIG.

The average value calculation unit 309 calculates an average value of each parameter and outputs the average value to the determination unit 308 when the detection unit 307 performs detection a plurality of times. For example, when the average value of the glossiness is obtained by performing detection processing twice for one recording material, it is obtained by the following equation.
PA = (P1 + P2) / 2
Here, P1 indicates the glossiness detected for the first time, and P2 indicates the glossiness detected for the second time. PA represents an average value of required glossiness.

  Here, according to the present embodiment, the determination unit 308 performs two determination processes: a simple determination for determining the type of the recording material, and a detailed determination. Simple discrimination refers to simple discrimination processing for discriminating the type of recording material corresponding to each parameter detected by one detection process by the detection unit 307. On the other hand, detailed discrimination means that the detection unit 307 executes detection processing a plurality of times while moving the detection position within the surface of the recording material, and the type of the recording material from the obtained average value of each parameter and the discrimination table. Detailed determination processing for determining

  The determination unit 303 determines whether or not the detailed determination process is necessary after the simple determination process is performed. For example, when the discriminating symmetrical recording material is the second and subsequent recording materials in the same print job, the determination unit 303 determines the type determined for the previous recording material and the current recording material. It is determined whether or not the type is the same. The determination unit 303 includes at least one of the parameters used in the simple determination process from various boundary lines for distinguishing types in the determination table to a determination line for determining similarity and dissimilarity. It is determined whether or not the value is included in the similar range. Details of this determination processing will be described later with reference to FIG.

  The determination unit 304 determines printing conditions such as a conveyance condition, a transfer condition, and a fixing condition from the determination result by the determination unit 308. For example, when the determination unit 303 determines that the type determined in the previous recording material is different from the type determined in the current recording material, the determination unit 304 prints from the determination result by the detailed determination process. Determine the conditions. On the other hand, when the determination unit 303 determines that they are the same, the determination unit 304 determines the printing condition from the determination result obtained by the simple determination process. In addition, when the determination unit 303 determines that the parameter used in the simple determination process is a value included in the similar range, the determination unit 304 determines the printing condition from the determination result by the detailed determination process. On the other hand, when the determination unit 303 determines that the value is not included in the similar range, the determination unit 304 determines the printing condition from the determination result obtained by the simple determination process.

  The inquiry unit 305 inquires of the operator whether or not the printing condition may be changed from the previous printing condition when the recording material to be discriminated is the second and subsequent recording materials in the same print job. . However, in the present embodiment, the inquiry unit 305 is not used. Details of the inquiry unit 305 will be described in the third embodiment.

  FIG. 4 is a diagram illustrating an example of a determination table for determining the type of recording material corresponding to the first embodiment. The discrimination table 401 will be described as a graph having glossiness on the vertical axis and transparency on the horizontal axis for ease of explanation. However, the discrimination table 401 is realized by storing information necessary for discriminating the recording material type as described below in the memory 310. In the graph shown in FIG. 4, the gloss level increases toward the right of the horizontal axis, and the transmittance decreases toward the top of the vertical axis.

  The discrimination table 401 is used by the discrimination unit 308 for comparison with each detected parameter (here, glossiness and transparency). For example, as shown in FIG. 4, the discrimination table 401 discriminates the type of recording material from plain paper, thick paper, and glossy paper based on glossiness and transparency. A boundary line 407 shown in FIG. 4 indicates a threshold value for classifying various types. That is, the detection result belonging to the region 404 divided by the vertical axis, the horizontal axis, and the boundary line 407 is determined as plain paper. Similarly, a region 405 indicates cardboard and a region 406 indicates gloss paper. The type of the recording material discriminated by the discriminating unit 308 is used for determining the printing condition by the determining unit 304.

  In order to realize such a discrimination function of the discrimination table 401, the memory 310 stores a threshold value serving as a boundary line 407 for discriminating a recording material. Further, the memory 310 stores two or more types of light emission amount data corresponding to the LED 201 and one type of light emission amount data corresponding to the LED 204. Further, the memory 310 stores the regular reflection light amount and the irregular reflection light amount measured by the phototransistors 202 and 203 using a reference sheet at the time of factory shipment. Thus, by adjusting the setting value of the detection process for each product, the image printing apparatus 100 can suppress variations in the detection process due to individual differences between the LEDs 201 and 204 and the phototransistors 202 and 203.

  FIG. 5 is a diagram illustrating an example of a determination result by a simple determination process corresponding to the first embodiment. Here, the discrimination accuracy by the simple discrimination process will be described using the discrimination table 401.

  Here, a discrimination result is shown in which simple discrimination processing using a detection result by the detection unit 307 is performed three times for plain paper, thick paper, and glossy paper. In FIG. 5, the triangle mark is detected using plain paper, the circle mark is detected using thick paper, and the square mark is detected using gloss paper. As shown in FIG. 5, in the simple determination process, the detection value varies even for the same recording material. As a result, the plain paper detection result 501 is mistakenly determined to be glossy paper because the glossiness is in the glossy paper range. Thus, in the simple discrimination process, the discrimination accuracy is lowered due to variations in detection results.

  FIG. 6 is a diagram illustrating an example of a determination result by the detailed determination process corresponding to the first embodiment. Here, the discrimination accuracy by the detailed discrimination process will be described using the discrimination table 401.

  Here, a discrimination result is shown in which detailed discrimination processing using a plurality of detection results by the detection unit 307 is performed three times for plain paper, thick paper, and glossy paper. In FIG. 6, the triangle mark is detected using plain paper, the circle mark is thick paper, and the square mark is detected using gloss paper. As shown in FIG. 6, in the detailed discrimination process, the variation in the detected value in the same recording material is smaller than the variation in the simple discrimination process shown in FIG. Therefore, the possibility of erroneously determining plain paper as glossy paper is very low as occurred in the simple determination processing. That is, the detailed determination process improves the accuracy of determining the type of recording material as compared to the simple determination process.

  However, in the detailed determination process, every time the detection position of the recording material is moved, the recording material is stopped and the operation of detecting the recording material is repeated. Compared with the simple determination process, the time required for the determination process Will increase. Usually, it takes about 800 ms to execute one detection process. That is, if the number of detection processes is N, the time required for multiple detection processes is about 800 × N (ms). Therefore, the image printing apparatus 100 according to the present embodiment can suppress an increase in detection time required for one print job to the minimum without reducing the recording material discrimination accuracy.

  FIG. 7 is a flowchart illustrating control for determining printing conditions corresponding to the first embodiment. Here, for convenience of explanation, a case where two sheets are continuously printed on one side in one print job will be described.

  In step S701, the main control unit 302 determines the type of recording material for the first sheet of the print job. The discrimination process here is a simple discrimination process. Specifically, the main control unit 302 first controls the transport mechanism unit 311 to transport the recording material to the position of the recording material determination sensor 101. Next, the main control unit 302 controls the light emitting element driving unit 306 to drive the LEDs 201 and 204 to start detection. Thereafter, the detection unit 307 acquires signals from the phototransistors 202 and 203 and detects glossiness and transmissivity, which are one or more parameters. The detection unit 307 outputs the detected glossiness and transparency values to the determination unit 308. The determination unit 308 uses the determination table 401 stored in the memory 310 to determine the type of recording material corresponding to the detected glossiness and transparency. The type determined here is 1A.

  Subsequently, in step S <b> 702, the determination unit 303 determines whether or not the glossiness and transparency detected in step S <b> 701 are values in a similar range in the determination table 401. Here, the similar range will be described with reference to FIG. FIG. 8 is a diagram illustrating a similar range in the determination table corresponding to the first embodiment. In FIG. 8, a similarity range 803 that is a range from the threshold value (glossiness X, transparency Y) indicating the boundary line 407 to ± σ (decision line) is added to the discrimination table 401. The similar range 803 indicates a range in which there is a high possibility that the type of the recording material is erroneously determined. For example, the recording material detection result 801 is within the range of the similar range 803. Further, the detection result 802 exists outside the range of the similar range 803. Here, by using step S <b> 702, the determination unit 308 performs the detailed determination process only for the detection result 801 that has a high possibility of being erroneously determined. Accordingly, the image printing apparatus 100 can suppress an increase in time required for determining the type of recording material to a minimum.

  When the detection result of the first recording material is outside the range of the similar range 803, the main control unit 302 shifts the process to S704. In step S704, the determination unit 304 determines the printing condition for the first recording material from type 1A. On the other hand, if it is within the range of the similar range 803, in step S703, the determination unit 308 performs a detailed determination process. The type determined here is 1B. In step S704, the determination unit 304 determines the printing condition for the first recording material from type 1B. When the printing conditions are determined, in step S705, the main control unit 302 forms an image on the recording material according to the determined printing conditions. In the following, it is assumed that the type of recording material used when determining the printing conditions for the first sheet is 1.

  Here, the detailed determination processing in S703 will be described. In detecting the glossiness, the main control unit 302 slightly moves the recording material and changes the light amount detection position of the recording material. Thereafter, the main control unit 302 causes the LED 201 to emit light again and obtains the glossiness (regular reflection light amount / diffuse reflection light amount) of the recording material. The obtained glossiness is defined as Pa1 '. Further, the glossiness obtained in S701 is defined as Pa1. The average value calculation unit 309 obtains an average value Pa1A (Pa1A = (Pa1 + Pa1 ′) / 2) between the glossiness Pa1 and the glossiness Pa1 ′. Further, in detecting the transmittance, the main control unit 302 slightly moves the recording material and changes the light amount detection position of the recording material. Thereafter, the main control unit 302 re-emits the LED 204 to determine the recording material transmittance (regular transmitted light amount). The obtained transmittance is defined as Pb1 '. Further, the transmittance determined in S701 is defined as Pb1. The average value calculator 309 obtains an average value Pb1A (Pb1A = (Pb1 + P1b ′) / 2) of the transmittance Pb1 and the transmittance Pb1 ′. The determination unit 308 uses the determination table 401 as a determination result for the type 1B corresponding to the average values Pa1A and Pb1A of the glossiness and the transmittance obtained by the average value calculation unit 309.

Next, in step S706, the main control unit 302 determines the type of recording material for the second sheet of the print job. The discrimination process here is a simple discrimination process. Since the process here is the same as S701, detailed description is abbreviate | omitted. The type determined here is 2A. Further, the glossiness of the obtained recording material is Pa2, and the transmittance is Pb2.

In step S707, the determination unit 303 determines whether the type 1 determined by the first recording material and the type 2A determined in S706 are the same. If it is determined that they are the same, in step S711, the determination unit 304 determines a printing condition from type 2A. If it is determined that they are the same, the determination unit 304 may determine the printing condition determined for the first sheet as it is as the printing condition for the second sheet. On the other hand, if it is determined that they are not the same, the main control unit 302 shifts the process to S708.

  In step S <b> 708, the determination unit 303 determines whether the glossiness Pa <b> 2 and the transparency Pb <b> 2 detected in step S <b> 706 are values in the similarity range 803 in the determination table 401. Detailed description is omitted because it overlaps with S702. If it is determined that the detection result is outside the range of the similar range 803, in step S711, the determination unit 304 determines the printing condition from the type 2A. Thereafter, in step S712, the main control unit 302 forms an image on the second recording material in accordance with the determined printing conditions. On the other hand, if it is determined that the detection result is within the range of the similar range 803, the main control unit 302 shifts the process to S709.

  In step S709, the determination unit 308 performs a detailed determination process. The type determined here is 2B. Subsequently, in step S710, the determination unit 304 determines the printing condition from the type 2B determined in step S709. Thereafter, in step S711, the main control unit 302 forms an image on the second recording material in accordance with the determined printing conditions.

  Further, according to the present embodiment, the similar range of the determination table 401 used for the determination of the second and subsequent detailed determination processes (S708) is the determination table used for the determination of the first detailed determination process (S702). This is different from the similar range 803 of 401. This is because unnecessary detailed determination processing is not performed by limiting the similar range of the second and subsequent sheets based on the type determined in the first recording material. The similar range after the second sheet will be described with reference to FIGS.

  FIG. 9 is a diagram illustrating a similar range in the determination table for the second and subsequent sheets when the first recording material corresponding to the first embodiment is determined to be plain paper. As shown in FIG. 9, when it is determined that the type of the first recording material is plain paper, the similarity range 901 includes the gloss threshold X + σ and the transparency threshold from the area determined to be plain paper. Y−σ is set. This is because there is a high possibility that the type of the actually determined recording material is plain paper as in the first sheet, so only the similar range on plain paper is the target of detailed discrimination processing.

  FIG. 10 is a diagram illustrating a similar range in the determination table for the second and subsequent sheets when the first recording material corresponding to the first embodiment is determined to be a thick sheet. As shown in FIG. 10, when it is determined that the type of the first recording material is thick paper, the similarity range 1001 is determined from the region determined to be thick paper as a gloss threshold X + σ and a transparency threshold Y + σ. Is set. This is because there is a high possibility that the type of recording material actually discriminated is cardboard as in the first sheet, and therefore, only the similar range in cardboard is subject to detailed discrimination processing.

  FIG. 11 is a diagram illustrating a similar range in the second and subsequent determination tables when the first recording material corresponding to the first embodiment is determined to be glossy paper. As shown in FIG. 11, when it is determined that the type of the first recording material is glossy paper, the similarity range 1101 is set as the glossiness threshold value X-σ from the area determined to be glossy paper. The This is because there is a high possibility that the type of recording material actually discriminated is glossy paper as in the first sheet, and therefore only the similar range on glossy paper is targeted for detailed discrimination processing.

  As described above, the image printing apparatus according to the present embodiment is used only when it is determined that the type of the previous recording material and the type determined in the current recording material are different in the same print job. Detailed detection processing is performed by performing detection processing a plurality of times. As a result, the image printing apparatus suppresses detection processing for detecting the property of the recording material to the minimum necessary. Accordingly, the image printing apparatus can improve the discrimination accuracy of the type of recording material while suppressing an increase in the time required for the discrimination process.

  The present invention is not limited to the above embodiment, and various modifications are possible. For example, the image printing apparatus may execute the detailed determination process only when at least one of the parameters used in the simple determination process is a value included in the similar range in the determination table. As a result, the image printing apparatus can reduce erroneous determination that is erroneously determined even for a recording material similar to other types. In addition, since the image printing apparatus performs the detailed determination process only on recording materials similar to other types, the determination accuracy can be improved without reducing the throughput of the entire determination process.

  In addition, the image printing apparatus may limit the similar range used for the discrimination process for the second and subsequent recording materials from the similar range used for the discrimination process for the first recording material. Thereby, the image printing apparatus can suppress unnecessary detail determination processing for the second and subsequent sheets. Therefore, the image printing apparatus can reduce the time required for the determination process while maintaining the accuracy of determining the type of the recording material.

In the image printing apparatus according to the present embodiment, the detailed determination process in which the detection position is changed only once and the number of detection times is two has been described. However, the number of detections in the detailed determination process is not limited to two, and the number may be increased according to the detection accuracy. Further, in the present embodiment, for convenience of explanation, the case where two sheets are continuously printed on one side in one print job has been described. However, when three or more sheets are continuously printed in one print job, the detailed determination process for the third and subsequent sheets may be omitted by comparing with the determination result for the previous sheet.

[Second Embodiment]
Next, a second embodiment will be described with reference to FIG. The image printing apparatus 100 according to the present embodiment is characterized in that the discrimination process is omitted for the recording material supplied from the same recording material cassettes 105 and 106 as the previous print job. FIG. 12 is a flowchart illustrating control for determining printing conditions corresponding to the second embodiment. Here, the description of the same steps as those in the flowchart shown in FIG. 7 is omitted. That is, the description from step S701 to step S712 is omitted here.

  In the image printing apparatus 100 according to the present embodiment, since the recording materials stacked in the recording material cassettes (CST) 105 and 106 are likely to be the same, the recording materials in the CST do not change when the CST is not opened or closed. Probability is high. For this reason, the image printing apparatus 100 omits the determination process for the first recording material by using the printing condition determined in the previous printing job as the first printing condition in the next printing job. . Thereby, the image printing apparatus 100 can shorten the first printout time. In the image printing apparatus 100, the printing condition determined in the print job or the type of recording material used for determining the printing condition is stored in the memory 310.

  In step S1201, the main control unit 302 determines the paper feed port designated in the started print job. Specifically, the main control unit 302 determines whether the designated paper feed port is the recording material cassette 105 or 106 or the multi-tray 107. In the case of the multi-tray 107, the main control unit 302 shifts the process to S701 and starts the determination process.

  On the other hand, in the case of the recording material cassettes 105 and 106, in step S1202, the main control unit 302 opens and closes after the corresponding recording material cassette (here, the recording material cassette 105) is used in the previous print job. It is determined whether or not. In this case, the opening / closing information of the recording material cassettes 105 and 106 may be acquired from the information stored in the memory 310. Further, the main control unit 302 may discard the printing condition or the printing condition determined in the previously used print job stored in the memory 310 for each of the recording material cassettes 105 and 106. Thereby, in the processing of S1202, the main control unit 302 may determine whether or not information on the previous print job is stored in the memory 310.

  If it is opened or closed, the main control unit 302 causes the process to transition to S701 and starts the determination process. On the other hand, if it has not been opened or closed, in step S1203, the main control unit 302 forms an image on the first recording material in accordance with the printing conditions determined in the previous print job stored in the memory 310.

  As described above, the image printing apparatus includes a plurality of recording material cassettes that supply recording materials, and a storage unit that stores, for each recording material cassette, the types determined in the recording materials supplied from the recording material cassettes. May further be included. In this case, the determination unit is the first recording material in the print job, and the recording material cassette that has supplied the first recording material stores the type last in the corresponding storage unit. The determination process may be omitted when the door has not been opened or closed since then. Further, the determination unit is obtained by executing at least a simple determination process when the recording material cassette to which the first recording material is supplied has been opened / closed since the type was last stored in the corresponding storage unit The printing conditions may be determined from the determination result. Thus, the image printing apparatus can omit unnecessary determination processing for the first recording material in the print job, and can further improve the printing throughput.

  In the present embodiment, the image printing apparatus having the recording material cassette and the multi-tray has been described. However, even in the image printing apparatus having the optional feeder, the same control as that of the recording material cassette according to the present embodiment can be executed. is there.

[Third Embodiment]
Next, a third embodiment will be described with reference to FIGS. 13 and 14. When the printing conditions are changed in the same print job, the recording material of the same print job may be printed under different printing conditions. This may be undesirable for the user because recording materials of the same print job have different image quality such as gloss value and fixability. Therefore, in the present embodiment, confirmation is made to the operator when the printing conditions are changed during the same print job.

  FIG. 13 is a flowchart illustrating control for determining printing conditions corresponding to the third embodiment. Here, the description of the same steps as those in the flowchart shown in FIG. 7 is omitted. That is, here, a detailed description is given only for the processing from step S1301 to step S1304. FIG. 14 is a diagram illustrating a printing system corresponding to the third embodiment.

  When the detail determination process for the second recording material is performed in S709, in step 1301, the determination unit 303 determines the type determined for the first recording material and the type determined by the detail determination process of S709. Are determined to be the same. If they are the same, the main control unit 302 shifts the processing to S1303, and sets the second printing condition to the same printing condition as that of the first recording material.

  On the other hand, if they are not the same, in step S1302, the inquiry unit 305 inquires of the operator whether the second printing condition may be changed from the first printing condition. Here, the inquiry unit 305 may display a confirmation screen on the display unit 1403 of the PC 1401 or the display operation panel 312 of the image printing apparatus 100 as shown in FIG. Input from the operator is transmitted to the main control unit 302.

  If the change is not permitted, in step S1303, the determination unit 304 sets the second printing condition to the same printing condition as the first recording material. On the other hand, if the change is permitted, in step S1304, the determination unit 304 determines the printing condition from the type determined in the detailed determination process in S709.

  As described above, the image printing apparatus determines whether or not the printing condition of the recording material may be changed when the determination result of the first sheet is different from the determination result of the second sheet in the same print job. Contact the operator. Thereby, this image printing apparatus can further improve the discrimination accuracy of the recording material. The image printing apparatus can provide a user-friendly operation system.

It is sectional drawing which shows an example of the image printing apparatus corresponding to 1st Embodiment. It is a figure which shows an example of the recording material discrimination | determination sensor corresponding to 1st Embodiment. It is a figure which shows an example of the control structure in the image printing apparatus corresponding to 1st Embodiment. It is a figure which shows an example of the discrimination | determination table for discriminating the classification of the recording material corresponding to 1st Embodiment. It is a figure which shows an example of the discrimination | determination result by the simple discrimination | determination process corresponding to 1st Embodiment. It is a figure which shows an example of the discrimination | determination result by the detailed discrimination | determination process corresponding to 1st Embodiment. 4 is a flowchart illustrating control for determining printing conditions corresponding to the first embodiment. It is a figure explaining the similar range in the discrimination | determination table corresponding to 1st Embodiment. FIG. 6 is a diagram illustrating a similar range in a determination table for the second and subsequent sheets when the first recording material corresponding to the first embodiment is determined to be plain paper. FIG. 10 is a diagram illustrating a similar range in a determination table for the second and subsequent sheets when the first recording material corresponding to the first embodiment is determined to be a thick sheet. FIG. 10 is a diagram illustrating a similar range in a determination table for the second and subsequent sheets when the first recording material corresponding to the first embodiment is determined to be glossy paper. 10 is a flowchart illustrating control for determining a printing condition corresponding to the second embodiment. 10 is a flowchart illustrating control for determining a printing condition corresponding to the third embodiment. It is a figure which shows the printing system corresponding to 3rd Embodiment.

Explanation of symbols

100: Image printing apparatus 101: Recording material discrimination sensor 102: Conveyance paths 103a to 103d: Image forming unit 104: Fixing unit 105, 106: Recording material cassette 107: Multi-tray

Claims (9)

An image printing apparatus,
A detection unit for detecting one or more parameters representing the property of each recording material;
A first discriminating unit for discriminating the type of recording material from each parameter detected by one detection process by the detecting unit, using a discrimination table in which a correspondence relationship between each parameter and the type of recording material is registered;
When the recording material to be discriminated is the second and subsequent recording materials in the same print job, the type of the previous recording material and the type of the current recording material discriminated by the first discrimination unit are A first determination unit for determining whether or not they are the same;
When it is determined that the type of the previous recording material is different from the type of the current recording material, the detection unit executes a plurality of detection processes while moving the detection position within the surface of the recording material. And a second discriminating unit that discriminates the type of the recording material from the obtained average value of each parameter and the discrimination table. When it is determined that the type of the previous recording material is different from the type of the current recording material, the printing condition is determined from the determination result by the second determination unit,
And a determination unit that determines a printing condition from a determination result by the first determination unit when it is determined that the type of the recording material of the previous sheet and the type of the recording material of this time are the same. The image printing apparatus according to claim 1, wherein: At least one of the parameters used for the determination processing by the first determination unit exists from various boundary lines for classifying the types in the determination table to a determination line for determining similarity and dissimilarity. A second determination unit that determines whether the value is included in the similar range;
The determination unit is
When it is determined that the value is included in the similar range, a printing condition is determined from a determination result obtained by executing a detailed determination process by the second determination unit;
The image printing apparatus according to claim 2, wherein when it is determined that the value is not included in the similar range, a printing condition is determined from a determination result by the first determination unit. The second determination unit includes
When the recording material to be discriminated is the first recording material in the print job, it is determined by applying the similar range in all types,
The determination is made by applying the similar range corresponding to the type of the recording material one sheet before when the recording material to be determined is the second or subsequent recording material in the same print job. 4. The image printing apparatus according to 3. A plurality of recording material cassettes for supplying the recording material;
A storage unit that stores, for each recording material cassette, the type determined in the recording material supplied from each recording material cassette;
In the determination unit, the recording material to be discriminated is the first recording material in the print job,
The discriminating process by the first discriminating unit and the second discriminating unit when the recording material cassette that has supplied the first recording material has not been opened / closed since the type was last stored in the corresponding storage unit Is omitted, the printing condition is determined from the type stored in the storage unit,
When the recording material cassette to which the first recording material is supplied has been opened / closed since the type was last stored in the corresponding storage unit, at least the determination processing by the first determination unit is executed. 5. The image printing apparatus according to claim 2, wherein a printing condition is determined from the determined determination result. The recording material to be discriminated is the second and subsequent recording materials in the same print job, and the type of the previous recording material is discriminated by the type discriminated by the first discriminating unit and the second discriminating unit. And an inquiry unit for inquiring whether or not the operator can change the printing condition determined in the previous recording material to a different printing condition when the type is different. The image printing apparatus according to claim 1. The type of the recording material includes plain paper, gloss paper having higher gloss than the plain paper, and thick paper having lower transparency than the plain paper. Image printing device.   The image printing apparatus according to claim 1, wherein the one or more parameters include at least one of glossiness and transparency. A control method for controlling an image printing apparatus,
A detection step of detecting one or more parameters representing the properties of each recording material;
A first determination step of determining a recording material type from each parameter detected by one detection process in the detection step using a determination table in which a correspondence relationship between each parameter and the recording material type is registered;
When the recording material to be discriminated is the second and subsequent recording materials in the same print job, the type of the previous recording material and the type of the current recording material discriminated in the first discrimination step are A first determination step of determining whether or not they are the same;
When it is determined that the type of the previous recording material is different from the type of the current recording material, a plurality of detection processes are executed by the detection step while moving the detection position within the surface of the recording material. And a second determination step of determining the type of the recording material from the obtained average value of each parameter and the determination table.

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