JP5493587B2 - Discharge phenomenon analysis device, particle behavior analysis device, particle behavior analysis system, program - Google Patents

Description

  The present invention relates to a discharge phenomenon analysis device, a particle behavior analysis device, a particle behavior analysis system, and a program.

  A mechanism for analyzing a discharge phenomenon occurring in various apparatuses by simulation is considered.

  For example, in Patent Document 1, in a simulation analysis method of a discharge phenomenon in a transfer process in an image forming apparatus, in the case of a simulation model in which charged particles are deposited on opposing surfaces, a position on the surface layer portion of the particles is determined. A mechanism has been proposed in which potential nodes are subject to potential difference calculation.

JP-A-2005-345120

  An object of the present invention is to provide a mechanism for improving analysis accuracy in an analysis by simulation of a discharge phenomenon.

The invention according to claim 1 includes a boundary setting unit that sets a boundary between the first surface and the second surface in the analysis target region sandwiched between the first surface and the second surface. Among the particles floating in the analysis target region, those belonging to the first surface side region across the boundary set by the boundary setting unit are included in the second surface side region. Analyzing the discharge phenomenon with the one belonging to the region, the region belonging to the second surface side across the boundary set by the boundary setting unit belongs to the region on the first surface side And a discharge analysis unit for analyzing a discharge phenomenon between the two.

According to a second aspect of the present invention, in the first aspect of the invention, the boundary setting unit sets a geometric intermediate position between the first surface and the second surface as the boundary. To do.

According to a third aspect of the present invention, in the first aspect of the present invention, the boundary setting unit is configured so that the charged particles are deposited on the first surface and the second surface. The geometrical relationship between the uppermost particle of the deposited particles and the surface facing the deposited particle or the uppermost particle of the particles deposited on the opposite surface. An intermediate position is set to the boundary.

According to a fourth aspect of the present invention, in the third aspect of the present invention, the boundary setting section has a geometric intermediate position with respect to the surface of the uppermost particle among the deposited particles. Set to the boundary.

According to a fifth aspect of the present invention, in the first aspect of the invention, the boundary setting unit sets an electrical intermediate position between the first surface and the second surface as the boundary. .

According to a sixth aspect of the present invention, in the invention of the fifth aspect, the boundary setting unit is configured such that when particles having a charge are deposited on the first surface or the second surface, An electrical intermediate between the top layer particle among the deposited particles and the surface facing the deposited particle or the top layer particle among the particles deposited on the opposite surface Set the position to the boundary.

According to a seventh aspect of the invention, in the invention of the fifth or sixth aspect, the boundary setting section floats in the analysis target region with respect to an electric field between the first surface and the second surface. The boundary is set by reflecting the amount of change caused by the particles.

According to an eighth aspect of the present invention, in the invention according to any one of the fifth to seventh aspects, when the potential change at the discharge search point of interest is not monotonous, the discharge analysis unit Are excluded from discharge analysis.

The invention according to a ninth aspect is the invention according to any one of the first to eighth aspects, wherein the discharge analysis section is arranged on the first surface side in the floating particles. For those belonging to the region, the discharge phenomenon is further analyzed between those belonging to the region on the first surface side, and those belonging to the region on the second surface side are further analyzed on the second surface side. Analyze the discharge phenomenon between those belonging to the region.

The invention according to claim 1 0, in the invention described in claim 9, wherein the discharge analysis unit, the analysis of the floating to have particles in the target area first surface portion and the second The first surface side portion and the first surface are further divided into the surface side portion, and those belonging to the first surface side region across the boundary set by the boundary setting unit. Analyzing the discharge phenomenon with the one belonging to the region on the side, and for the one belonging to the region on the second surface side across the boundary set by the boundary setting unit, the second surface The discharge phenomenon between the portion on the side and the portion belonging to the region on the second surface side is analyzed.

The invention of claim 1 1, in the invention described in claim 9 or 1 0, the discharge analysis unit, and the first surface of the surfaces of the particles suspended in the analysis target area Analyzing a discharge phenomenon between the particles belonging to the first surface side region, the second surface side surface and the second surface side region of particles floating in the analysis target region Analyze the discharge phenomenon between the two.

The invention according to claim 1 2 is the invention according to claim 1, wherein the discharge analyzer analyzes a discharge phenomenon occurring at the surface of the particles suspended in the analysis target area.

The invention according to claim 1 3, in the analysis target area sandwiched between the first surface and a second surface, the first surface and the intermediate boundary setting unit for setting a boundary of the second surface Among the particles floating in the analysis target region, those belonging to the first surface side region across the boundary set by the boundary setting unit are the second surface side region. Analyzing the discharge phenomenon with respect to those belonging to the area, and those belonging to the area on the second surface side across the boundary set by the boundary setting unit belong to the area on the first surface side A discharge analysis unit for analyzing a discharge phenomenon between the first and second particles, and a motion for analyzing the motion of each particle existing in the analysis target region based on the physical property information of the particle after the discharge phenomenon analysis result by the discharge analysis unit A particle behavior analysis apparatus comprising: an analysis unit.

The invention according to claim 1 4, performs particle behavior calculated according division method of predetermined parallel processing based on the property information of the analyzed particles receiving unit and said receiving unit has received that accepts distributed analyzed elements A plurality of particle behavior calculation units, and a distribution processing unit that distributes the analysis target element within the analysis target range to each of the plurality of particle behavior analysis devices according to the division method. A boundary setting unit for setting a boundary between the first surface and the second surface in the analysis target region sandwiched between the first surface and the second surface; and floating in the analysis target region Among particles that belong to the region on the first surface side across the boundary set by the boundary setting unit, discharge phenomenon between the particles belonging to the region on the second surface side is performed. By analyzing the boundary setting unit A discharge analysis unit for analyzing a discharge phenomenon between the first surface side region and the one belonging to the second surface side region across the set boundary; and the discharge analysis unit The particle behavior analysis system includes a motion analysis unit that analyzes the motion of each particle existing in the analysis target region based on the physical property information of the particle after the analysis result of the discharge phenomenon due to.

The invention according to claim 1 5, in the analysis target area sandwiched between the first surface and a second surface, the first surface and the intermediate boundary setting unit for setting a boundary of the second surface Among the particles floating in the analysis target region, those belonging to the first surface side region across the boundary set by the boundary setting unit are the second surface side region. Analyzing the discharge phenomenon with respect to those belonging to the area, and those belonging to the area on the second surface side across the boundary set by the boundary setting unit belong to the area on the first surface side And a program that causes the electronic computer to function as a discharge analysis unit that analyzes the discharge phenomenon between the two.

According to the invention described in claims 1 and 15 , in the analysis by the simulation of the discharge phenomenon, the analysis accuracy is improved as compared with the case where the suspended particles in the analysis target region are not the target of the discharge analysis.

According to the first aspect of the present invention, the discharge analysis can be performed according to the region to which the suspended particles belong to the region boundary at the intermediate position.

According to the second aspect of the present invention, the region boundary can be easily set.

According to the third aspect of the present invention, the accuracy of the discharge analysis between the floating particles and the deposited particles is improved as compared with the case where the substantial charge surface fluctuation due to the deposited particles is not taken into consideration.

According to the fourth aspect of the present invention, the accuracy of the discharge analysis between the floating particles and the deposited particles is improved as compared with the case where the surface other than the surface of the uppermost layer of the deposited particles is applied.

According to the invention described in claim 5 , when the geometric intermediate position and the electrical intermediate position do not coincide with each other, the accuracy of the discharge analysis is improved as compared with the case where the invention according to claim 5 is not adopted. To do.

According to the invention described in claim 6, when the factors geometrical intermediate position and electrical intermediate position does not match it is in the deposition particles, as compared with the case not employing the invention according to the claims 6 The accuracy of discharge analysis is improved.

According to the invention described in claim 7 , when the suspended particle has a factor that the geometric intermediate position and the electrical intermediate position do not coincide with each other, as compared with the case where the invention according to claim 7 is not adopted. The accuracy of discharge analysis is improved.

According to the eighth aspect of the present invention, when the potential change at the discharge search location of interest is not monotonous, an analysis that is more realistic than the case where the discharge search location is the target of the discharge analysis can be performed.

According to the invention described in claim 9, as compared with the case not employing the invention according to the present claim 9 to improve the accuracy of the discharge analysis.

According to the invention of claim 1 0, than without employing the process of dividing the suspended particles to a first surface side portion and the second surface side portion, according to the claim 1 0 invention Easy to do.

According to the invention of claim 1 1, when carrying out the invention of claim 9 or 1 0, than when applying the other surface of the suspended particles, the accuracy of the discharge analysis is improved.

According to the invention of claim 1 2, than the case of applying the non-surface of the suspended particles, the accuracy of the discharge analysis is improved.

According to the invention described in claims 1 to 3, it is particle behavior analysis suspended particles also reflect the discharge analysis results of the object of the analysis target area.

According to the invention described in claim 1 4, particle behavior analysis suspended particles also reflect the discharge analysis results of the object of the analysis target area is than without adopting the invention according to the claims 1 4 short You can do it in time.

It is a figure which shows the example of 1 structure of the electrophotographic image forming apparatus which is an example of the apparatus in which the analysis object particle | grains made into object by the discharge phenomenon analysis process and particle behavior analysis process of this embodiment exist. It is a block diagram which shows the basic composition of a particle behavior analysis system. It is a figure explaining the structural example of a main particle behavior analysis apparatus. It is a figure explaining the structural example of a secondary particle behavior analysis apparatus. It is a figure explaining the example of composition of a particle behavior analysis device. It is a figure explaining the example of composition of a numerical operation processing part (particle behavior calculation part). It is a flowchart explaining an example of the process sequence of the particle behavior analysis process containing the discharge analysis process of this embodiment. It is the schematic which showed the basic view of the discharge analysis process of this embodiment. It is a figure explaining the discharge analysis process of 1st Embodiment. It is a figure explaining the discharge analysis process of 2nd Embodiment. It is FIG. (1) explaining the discharge analysis process of 3rd Embodiment. It is FIG. (2) explaining the discharge analysis process of 3rd Embodiment. It is a figure explaining the discharge analysis process of 4th Embodiment. It is a block diagram which shows the structural example when comprising a particle behavior analyzer using an electronic computer.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. When distinguishing each functional element according to the embodiment, an uppercase English reference such as A, B, C,... Is added and described. Omitted and listed. The same applies to the drawings.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, as an apparatus in which particles to be analyzed by the particle behavior analysis apparatus exist, an image forming apparatus such as a printer apparatus, a facsimile apparatus, or a multifunction machine having these functions will be described as an example.

  In relation to the analysis target particles, attention is paid to behavior analysis of developer particles in an electrophotographic image forming apparatus that uses only toner particles or a developer composed of carrier particles and toner particles. However, this is only an example, and the apparatus in which the particles to be analyzed exist is not limited to the image forming apparatus. In particular, in relation to the discharge analysis focused on in the present embodiment, any device that causes a discharge phenomenon between the focused particle and other members (including other particles), The embodiments described below can be applied.

<Outline of image forming apparatus>
FIG. 1 is a diagram illustrating a configuration example of an electrophotographic image forming apparatus that is an example of an apparatus in which target analysis target particles exist in a discharge phenomenon analysis process and a particle behavior analysis process of the present embodiment.

  In this configuration, assuming that it is for color image formation, the configuration of the main part related to image formation is not to transfer the toner image of the image carrier onto the paper as the transfer body directly onto the paper with the transfer device. A tandem configuration is adopted in which image forming units (output engines) for each output color are arranged in a line. For example, a plurality of output engines corresponding to output colors of K (black), Y (yellow), M (magenta), and C (cyan) are arranged in-line in the order of K → Y → M → C, for example. , Y, M, C images are processed in parallel (simultaneously) by four output engines. The toner image on the image carrier is transferred to the intermediate transfer member for each color at a time corresponding to the arrangement position (especially referred to as primary transfer), and then the toner image on the intermediate transfer member is transferred to the paper (particularly secondary transfer). It is configured to transfer). The figure shows a part of it.

  As shown in the figure, the image forming apparatus 1 is centered on a photoreceptor 10 (photoreceptor drum) that is an example of an image carrier, and includes a charging device 20, an exposure device 30, a developing device 40 that includes a stirring mechanism (not shown), and a transfer device. The apparatus 50 (a primary transfer device 50a and a secondary transfer device 50b), an intermediate transfer belt 58 as an example of an intermediate transfer member, a cleaning device 60 having a blade mechanism, and a fixing device 70 are provided.

  The charging device 20 includes a DC power source 22, an AC bias power source 24, and a charging unit 26 disposed in the vicinity of the photoconductor 10. The exposure apparatus 30 includes a laser light source 32, a polygon mirror 34, and a motor 36. The transfer device 50 includes a transfer power source 52 and a transfer unit 54.

  The developing device 40 is filled with developer particles 102. In the figure, one developer particle 102 is indicated by one circle for convenience. Actually, the developer particles 102 contain, for example, carrier particles (having magnetic properties) and non-magnetic toner particles (for example, toner particles of each color) composed of magnetic materials having different physical properties and particle sizes as main components. Two-component system. The pair of carrier particles and toner particles forms a magnetic powder as a whole. The toner particles are adsorbed to the carrier particles by electrostatic force. In general, the particle size of the carrier particles is larger than the particle size of the toner particles. As the toner particles, magnetic toner may be used, and in this case, carrier particles may not be used. The developer particles 102 actually further include other particles such as external additives.

  The developing device 40 has a developing roll 140 (also referred to as a mag roll, a magnet roller, or a magnetic transport roller), which is an example of a rotating roll that rotates with the developer particles 102 on the surface, in the storage container 101, and a peripheral surface that is open. Prepare to protrude slightly from the portion 101a. A predetermined number of magnets 142 are arranged in the developing roll 140 at predetermined intervals along the inner periphery.

  Further, the developing device 40 includes a regulating trimmer 150 that functions as a height regulating member, a layer forming member, and a layer regulating member in the vicinity of the developing roll 140, and the magnetic force of the developer particles 102 formed along the magnetic lines of force by the magnet 142. The height of the brush is regulated.

  Although illustration is omitted, in the storage container 101, an agitating and conveying roll that agitates the developer particles 102 and conveys the developer particles 102 to the developing roll 140 side is provided. The agitating and conveying roll conveys the developer particles 102 to the developing roll 140 side while agitating by the rotating operation.

  The developing roll 140 rotates together with the photoconductor 10 rotated in the direction of arrow X, and the rotational movement direction of the surface on the side facing the photoconductor 10 rotates in the same direction as the movement direction X of the photoconductor 10 (arrow Y direction). Is done. The photosensitive member 10 may be driven to rotate in the direction opposite to the moving direction X.

  The developer particles 102 are conveyed to the developing roll 140 side while being agitated and frictionally charged by an agitating and conveying roll (not shown) having an agitating function. The regulation trimmer 150 regulates the amount of the developer particles 102 adsorbed to the developing roll 140, and the developer particles 102 adhere to the periphery of the developing roll 140 at a certain height. The carrier particles constitute a magnetic brush by a magnetic field from a magnet 142 built in the developing roll 140. The toner particles are transported together with the carrier particles to a portion facing the photoreceptor 10.

  When the image forming apparatus 1 is configured as a copying apparatus, the charging device 20 generates a charging potential (initial potential) by superimposing the AC bias voltage from the AC bias power source 24 on the DC voltage from the DC power source 22, and this charging. The surface of the photoconductor 10 is charged to a uniform surface potential with an electric potential.

  After that, a polygon mirror 34 that is rotated by a motor 36 with a laser beam emitted from a laser light source 32 provided on the exposure device 30 on the surface of the photoreceptor 10 in accordance with image data obtained by scanning the original with a reading device (not shown). Scanning, the surface of the photoconductor 10 is exposed to form an electrostatic latent image having a latent image potential.

  Subsequently, the developing device 40 forms the toner particles in the developer particles 102 on the surface of the photoconductor 10 while mixing the developer particles 102 such as output color toner particles and carrier particles in a stirring mechanism (not shown). A toner image is formed on the surface of the photoconductor 10 by being superimposed on the electrostatic latent image.

  That is, the developing roller 140 is provided to face the photoconductor 10, and the toner particles among the developer particles 102 adsorbed to the developing roller 140 are charged and are adsorbed to the photoconductor 10 by electrostatic force. The At this time, an electrostatic latent image is formed on the surface of the photoreceptor 10 by exposure according to a recorded image, and toner particles are adsorbed according to the electrostatic latent image formed on the photoreceptor 10. The As a result, the latent image formed on the surface of the photoconductor 10 is developed. The carrier particles after the development processing and the toner particles that have not been ejected to the photoconductor 10 are collected in the storage container 101.

  Thereafter, the primary transfer device 50 a transfers the toner image formed on the surface of the photoreceptor 10 onto the intermediate transfer belt 58. A predetermined range in which the photosensitive member 10 and the transfer portion 54a face each other is referred to as a primary transfer region.

  On the other hand, the cleaning device 60 removes residual toner remaining on the surface of the photoreceptor 10 after being transferred by the transfer device 50. Although the residual potential remains on the surface of the photoreceptor 10 after cleaning, it is used in the next electrophotographic process after the initial potential is applied by the charging device 20.

  The toner image on the intermediate transfer belt 58 is sent to the transfer unit 54b side of the secondary transfer device 50b. In synchronization with this operation, the paper is picked up from the paper feed tray by the pick-up roller, and the paper is further transported to the transfer section 54b side of the secondary transfer device 50b by the paper transport roll. As a result, the toner image on the intermediate transfer belt 58 is transferred onto the sheet by the secondary transfer device 50b (transfer unit 54b). A predetermined range in which the intermediate transfer belt 58 and the transfer portion 54b face each other is referred to as a secondary transfer region.

  The transferred sheet is conveyed to the fixing device 70 side, and the fixing device 70 fixes the toner image onto a printing sheet as a transfer body by heating, melting and pressing. The fixed paper is discharged out of the image forming apparatus 1 by a discharge device (not shown).

  Such an electrophotographic process includes charging the photosensitive member 10, exposing a document image, developing, that is, superimposing toner on the photosensitive member 10, transferring toner to a transfer member (intermediate transfer belt 58 and paper), and fixing the toner. It consists of a plurality of steps of cleaning.

  In the electrophotographic process, for example, by applying a powder behavior analysis simulation in each process such as stirring, development, and transfer, an image to be formed is predicted and evaluated without actually performing an image forming experiment. At this time, in particular, analysis of the behavior of carrier particles and toner particles becomes an important factor for the development of the electrophotographic apparatus main body and the developing apparatus 40.

  For example, in the transfer process in the transfer device 50, while changing the condition parameters in the transfer process such as the surface roughness of the photoreceptor, the speed difference between the transfer bodies such as the photoreceptor / intermediate transfer belt and paper, and the contact width of the transfer body, By repeating the powder behavior analysis simulation, the image quality formed is evaluated while reproducing the transfer process. Incidentally, in the particle behavior analysis for the transfer process, an electric field and a gravitational field acting on the developer particles 102 (particularly toner particles) are considered. For example, a discharge phenomenon between particles in an electric field (electric field) or between a particle and a surface is analyzed.

<Particle behavior analysis system>
FIG. 2 is a block diagram showing the basic configuration of the particle behavior analysis system. The particle behavior analysis system 200 having a basic configuration includes a plurality of particle behavior analysis devices 202 each having a particle behavior analysis function so that parallel processing by a plurality of particle behavior analysis devices is performed in order to shorten the time of the particle behavior analysis processing. It is configured with a network connection.

  Each particle behavior analysis device 202 communicates main processing data to each other via a network 208, and can perform particle behavior analysis processing in parallel. It is configured as a parallel computing device (cluster computer). The network 208 is managed by a network management device 208a whose communication state has a routing function.

  As an example, each particle behavior analysis device 202 may be configured by the same as a general electronic computer. Here, in the illustrated example, one of the particle behavior analysis apparatuses 202 constituting the particle behavior analysis system 200 functions as a main particle behavior analysis apparatus 202a having a function of a calculation management node that controls the whole. It has become. The remaining particle behavior analysis device 202 is connected to the main particle behavior analysis device 202a as a sub particle behavior analysis device 202b controlled by the main particle behavior analysis device 202a.

  In the figure, for convenience, one network line is drawn from the network management device 208a, and the main particle behavior analysis device 202a and the secondary particle behavior analysis device 202b are connected to the network line. Each particle behavior analysis device 202 is connected to an individual port provided in the network management device 208a, and communication between each particle behavior analysis device 202 is performed via the network management device 208a. .

  Connected to the main particle behavior analysis device 202a are an instruction input device 210 such as a keyboard and a mouse for performing various operations for particle behavior analysis processing, and a display device 212 for presenting the processing results as image information to the operator. Has been. The instruction input device 210 and the display device 212 are collectively referred to as a GUI (Graphical User Interface), and the display screen of the display device 212 is referred to as a GUI screen.

  With such a basic system configuration, when performing a particle behavior analysis process for a system having a plurality of types of interparticle interactions, a behavior analysis is performed in parallel processing by applying a predetermined division method. Examples of the particle behavior analysis processing include dielectric constant analysis, charge analysis, discharge analysis, and motion analysis.

  Here, as an algorithm (division method) for parallel calculation of particle behavior analysis, for example, a region division method, a particle division method, a force division method and the like are known. In this embodiment, any of them may be adopted.

  In the basic configuration of the particle behavior analysis system 200 shown in FIG. 2, the configuration of a virtual parallel computer (cluster computer) is shown, but this is only an example. Although not shown in the figure, a plurality of particle behavior analysis systems each configured with a plurality of particle behavior analysis devices each having a particle behavior analysis function connected to the first network as a parallel computer are further separated. It is good also as what was connected and comprised by the 2nd network. In this case, each particle behavior analysis system communicates main processing data to each other via an external network (second network), and executes different particle behavior analysis processing for each target in parallel. The particle behavior analysis system of such a modified example is configured as a grid type computing device formed by connecting virtually parallel computing devices over a network.

<Particle behavior analyzer>
3 to 3B are diagrams for explaining the particle behavior analysis apparatus 202. FIG. 3 is a block diagram focusing on the main particle behavior analysis apparatus 202a having the function of a calculation management node in the particle behavior analysis system 200. FIG. 3A is a block diagram focusing on the secondary particle behavior analysis apparatus 202b having the function of a general node in the particle behavior analysis system 200. The main particle behavior analysis device 202a includes a sub particle behavior analysis device 202b. FIG. 3B is a configuration example in the case where the particle behavior analysis processing is performed by one particle behavior analysis device 202 instead of the parallel processing.

  As shown in FIG. 3, the main particle behavior analysis device 202a uses a command input device 210 or the like to input data to be processed 220, a data processing unit 230 for performing particle behavior analysis processing, and a processing result. An information presenting unit 240 that presents to the operator using the display device 212 or the like is provided. The data input part 220 and the information presentation part 240 are provided in the part corresponded to the calculation management node of the main particle behavior analysis apparatus 202a. As shown in FIG. 3A, the secondary particle behavior analysis apparatus 202b may be configured by only the data processing unit 230.

  The data processing unit 230 of each particle behavior analysis apparatus 202 applies a particle behavior analysis method to which an individual element method for tracking the behavior of individual particles based on the equation of motion is applied. In addition, at least when applying the individual element method, a plurality of particles to which any of the region division method, force division method, particle division method, a combination of these, or any other division method is applied. Parallel processing by the behavior analysis device 202 is applied.

  The region division method is a method in which an analysis region (calculation target region) that is a processing target element is divided, and all particles existing in the region are allocated to each processor (particle behavior analysis device 202) for each divided region. is there. The particle division method is a method of dividing a calculation target particle, which is a processing target element, into a predetermined number and assigning it to each processor (particle behavior analysis device 202) arranged in a matrix. The force division method is a method using an algorithm using a force matrix. The force division method is similar to the particle division method in that the analysis target particles of each processor arranged in a matrix are assigned, but the method of assigning the analysis target particles and the concept of the communication partner at the time of calculation processing are different.

  In the casing on the calculation management node side of the main particle behavior analysis apparatus 202a, the processing target element is divided according to various division methods, and each divided analysis target element (divided portion) is subjected to particle behavior according to a predetermined division method. A division processing unit 250 (distribution processing unit) that is allocated (distributed) to each calculation system (also referred to as a processor: particle behavior analysis apparatus 202 in the figure) that performs analysis is provided.

  When performing particle behavior analysis by parallel processing using a plurality of particle behavior analysis devices 202, the entire analysis target device is not collectively divided into division targets, but the analysis target region is divided into a plurality of regions. In addition, it is preferable to apply a predetermined division method to each of the divided analysis target areas.

  The data input unit 220 accepts commands and data input by the operator via the keyboard and mouse constituting the instruction input device 210 and passes them to the data processing unit 230.

  The data processing unit 230 performs a particle behavior analysis process based on the data input from the data input unit 220. Therefore, the data processing unit 230 includes a data receiving unit 232, a numerical operation processing unit 234, a bus interface unit 235, a memory access control unit 237, and a data storage unit 238. The data processing unit 230 is included in the secondary particle behavior analysis apparatus 202b.

  Note that the numerical operation processing unit 234, the bus interface unit 235, and the temporary storage unit 238a may be configured as a processor core unit 239 provided in the same package (housing). The processor core unit 239 is configured by a single core core CPU including a single processor core (also simply referred to as “core”) that performs numerical calculation processing and a built-in memory (temporary storage unit 238a). The processor core unit 239 includes a bus interface unit 235 that functions as an output data processing unit in addition to the numerical operation processing unit 234 and the temporary storage unit 238a.

  The numerical arithmetic processing unit 234 performs input / output (memory access) of data (information) to and from the data storage unit 238 in accordance with the determined division method for the divided portion assigned by the division processing by the division processing unit 250. It functions as a particle behavior calculator that performs calculations.

  The bus interface unit 235 inputs / outputs data to / from the numerical operation processing unit 234. In addition to the function of transferring data in the analysis process to / from the other particle behavior analysis apparatus 202, the bus interface unit 235 performs the numerical operation processing unit 234. It also functions as an output data processing unit that outputs the analysis result (including intermediate progress) acquired in step (b) to the information presentation unit 240.

  The data storage unit 238 is a device that stores data of a parameter table for calculating the interaction, and is connected to the numerical operation processing unit 234. Here, the data storage unit 238 includes a temporary storage unit 238a and an external storage device 238b. The temporary storage unit 238a is a temporary storage unit 238a similar to a built-in memory (also referred to as a cache memory) built on the same semiconductor substrate as the so-called CPU, and numerical values are transmitted via a memory bus (MBUS). Connected to the arithmetic processing unit 234. The external storage device 238b is an external semiconductor storage medium called a so-called main memory (for example, having a capacity of several hundred MB to several GB) or a hard disk device (HDD) having a larger capacity (several hundred GB or more) than the main memory. The numerical arithmetic processing unit 234 is connected to a bus different from the memory bus.

  The data receiving unit 232 stores the data input from the data input unit 220 in the external storage device 238b of the data storage unit 238. For example, the configuration of the device that handles the particles to be analyzed, various physical parameters (data related to physical property values) necessary for the calculation, the initial arrangement of the particles, the number of particles to be analyzed, the convergence conditions of the simulation, etc. Stored in 238b.

  Based on the data supplied from the data receiving unit 232 to the data storage unit 238, the numerical calculation processing unit 234 performs, for example, dielectric constant analysis, charge analysis, discharge analysis, motion analysis, and the like on the analysis target particles. Analysis is performed by simulation processing by applying the division method. During the calculation, data is stored and read with the temporary storage unit 238a as appropriate. The numerical arithmetic processing unit 234 supplies the analysis result to the information presenting unit 240 via the bus interface unit 235 (functional unit of the output data processing unit).

  The information presentation unit 240 receives the calculation result in the numerical calculation processing unit 234, converts the calculation result in the numerical calculation processing unit 234 into display data, and supplies the display data to the display device 212. For example, display information indicating results such as potential distribution, charge amount distribution, particle behavior, charge distribution, and discharge distribution of the analysis coping area acquired by the numerical calculation processing unit 234 is supplied to the display device 212. The display device 212 displays a processing result image based on the display information supplied from the information presentation unit 240. The behavior prediction of the developer particle 102 is visualized and displayed on the display device 212 so that the behavior of the developer particle 102 that is actually difficult to confirm can be visually grasped.

  Here, the division processing unit 250 is provided in the main particle behavior analysis apparatus 202a functioning as a calculation management node, and the main particle behavior analysis apparatus 202a is also described as the particle behavior analysis apparatus 202 that constitutes a part of the particle behavior analysis system 200. However, this is not essential. A system configuration in which the division processing unit 250 is provided in an information processing device different from the plurality of particle behavior analysis devices 202 (computers) that perform particle behavior analysis may be employed. In that case, a dedicated device that distributes the analysis target element handled by each particle behavior analysis device is required, so that there is one more dedicated information processing device (computer) than the configuration example shown here.

  3 and 3A, the main particle behavior analysis device 202a and the secondary particle behavior analysis device 202b are shown to perform parallel processing by a plurality of particle behavior analysis devices 202 in order to shorten the time of the particle behavior analysis processing. . However, it is not indispensable to perform the particle behavior analysis processing by parallel processing, and may be performed by the single particle behavior analysis device 202. For example, as shown in FIG. 3B, the single particle behavior analysis apparatus 202 may be configured by removing the division processing unit 250 from the main particle behavior analysis apparatus 202 a, and in that case, the single particle behavior analysis apparatus 202. Is equivalent to the particle behavior analysis system 200.

<Configuration of numerical arithmetic processing unit>
FIG. 3C is a diagram illustrating a configuration example of a numerical calculation processing unit 234 (particle behavior calculation unit) provided in the particle behavior analysis apparatus 202.

  Specifically, the numerical calculation processing unit 234 includes a conductor charge transfer analysis processing unit 420, a boundary setting unit 430, a discharge analysis unit 440, a motion analysis unit 460, and a charge transfer analysis unit 470. The discharge phenomenon analysis apparatus 402 is configured by a portion excluding the motion analysis unit 460 among these.

  There are a finite element method and a difference method as a method for calculating the electric field, and any of them can be adopted in the present embodiment. However, the following description will be made assuming that the finite element method is applied unless otherwise specified.

  The in-conductor charge transfer analysis processing unit 420 includes a dielectric constant analysis unit 422, a charge analysis unit 424, and a charge transfer analysis unit 426.

  The dielectric constant analysis unit 422 calculates data that takes into account the dielectric constant of the toner particles in the distribution of the dielectric constant in the mesh data based on information such as the position, shape, diameter, and dielectric constant of each toner particle.

  The charge analysis unit 424 calculates data in consideration of the charge distribution of the toner particles in the distribution of the true charge in the mesh data.

  The charge transfer analysis unit 426 calculates the charge transfer in the conductor according to Ohm's law.

  The boundary setting unit 430 sets another boundary between two opposing boundaries (charge planes) according to a predetermined method.

  The discharge analysis unit 440 determines the occurrence of discharge and calculates the movement of charges due to discharge and the potential distribution after discharge. Specifically, the discharge extraction unit 442 between the opposing surfaces, the discharge extraction unit 444 between the peak members, A discharge charge amount calculation unit 446 and a charge update unit 448 are included.

  The counter-surface discharge extraction unit 442 searches for the presence or absence of discharge between two opposing planes according to Paschen's discharge rule, and extracts a portion to be discharged. The counter-surface discharge extraction unit 442 uses the boundary information set by the boundary setting unit 430 to extract a portion to be discharged.

  The search for the occurrence of discharge uses the part of the mesh data defining the potential as an unknown variable (referred to as a potential definition segment or simply a segment) on or near the surface where the discharge is searched. This is realized by extracting the discharge definition segment on the opposite surface that exceeds the Paschen voltage most with respect to the potential definition segment. A segment on or near the surface used for the search is called a discharge search segment, the extracted potential definition segment is called a discharge segment, and a set with a discharge partner is called a discharge segment pair. As the Paschen voltage, various types of the approximation of the Paschen voltage indicated by an approximate curve have been proposed, and any of them may be used.

  Here, when the surface is covered with a layer of toner particles deposited on the surface (hereinafter also referred to as a toner layer), the opposed surface discharge extraction unit 442 searches for the potential definition segment of the covered portion. Exclude from Instead, the toner particles positioned on the surface of the toner layer deposited on the surface are made to correspond to potential definition segments (particularly referred to as toner segments) close to the toner particles, and the toner segments are discharged. Used for searching.

  The peak member discharge extraction unit 444 extracts a discharge segment pair based on the experimental result indicating the relationship between the gap length and the discharge start voltage between two bodies that do not follow Paschen's discharge rule, such as a static elimination needle.

  The discharge charge amount calculation unit 446 calculates the potential after the discharge and the discharge charge amount according to a predetermined calculation formula (here, description thereof is omitted: see Formulas 2 to 4 in Patent Document 1). The charge amount of the discharge segment other than the toner segment is updated by adding the discharge charge amount obtained here.

  The charge update unit 448 converts the toner particle that is the source of toner segment extraction when the potential definition segment in which discharge is generated in the discharge charge amount calculated by the discharge charge amount calculation unit 446 is a toner segment. On the other hand, the charge amount is updated by the amount corresponding to the discharge charge.

  The motion analysis unit 460 solves Newton's equation of motion based on the force acting on the toner particles in the transfer area, such as electrostatic force, gravity, adhesion force, and air resistance force, and updates the coordinates of the toner particles to the position after the calculation interval. To do.

  The charge transfer analysis unit 470 analyzes the charge transfer accompanying the movement of the object. For example, charge is generally present only on the surface of an object. The surface of the object on which charges can be accumulated is referred to as a charge surface. Here, when considering the motion of the object, the charge may be moved in the direction of motion of the object between the nodes constituting the charge surface.

  As the charge surface when analyzing the behavior in the transfer process in the image forming apparatus 1, for example, the surface of the photoreceptor 10 and the intermediate transfer belt 58 corresponds in the primary transfer region, and the intermediate transfer belt 58 in the secondary transfer region. Applicable to the front side of the paper. Although they may actually be in close contact with each other, the charge transfer analysis unit 470 executes the simulation by moving the true charge on the charge surface in the direction of movement of the object, assuming that there is a minute gap. To do.

<Outline of particle behavior analysis processing>
4A to 4A are diagrams for explaining the particle behavior analysis processing of the present embodiment. Here, FIG. 4 is a flowchart for explaining an example of the processing procedure of the particle behavior analysis process including the discharge analysis process of the present embodiment. FIG. 4A is a schematic diagram showing a basic concept of the discharge analysis processing of the present embodiment.

  In the present embodiment, a finite element method is adopted as a technique for performing electric field calculation. In the finite element method, since the potential is defined by a node, the potential definition segment is a node. Based on this point, in the following, the discharge segment is referred to as “discharge node”, the discharge search segment to be analyzed for discharge is “discharge search node”, the discharge segment pair is “discharge node pair”, and the toner segment is “toner node”. ".

  Further, in the discharge analysis processing of the present embodiment, the potential distribution when the discharge does not occur first is obtained, the discharge occurrence location (discharge node pair) is extracted from the result, and the discharge start voltage (for example, Paschen voltage) is obtained. It is determined how much charge should be transferred so as not to exceed. Based on Formulas 2 to 4 shown in Patent Document 1 (Formulas 3 and 4 are created from the potential distribution when no discharge occurs), these formulas are combined with formulas for electric field calculation. To analyze.

[Particle behavior analysis processing]
In this embodiment, parallel processing by a plurality of particle behavior analysis devices 202 is performed in order to shorten the time of the particle behavior analysis processing. For this purpose, various parallel algorithms such as a particle division method, a region division method, and a force division method are applied. In this case, the division processing unit 250 assigns a responsible portion to each particle behavior analysis apparatus 202. Hereinafter, as an example, a case where the force division method is applied will be described.

  First, the number of particle behavior analysis devices 202 constituting the particle behavior analysis system 200 that can be used for the particle behavior analysis processing to which the parallelization processing is applied at present (processors). Number) is specified (S102).

  Thereafter, the main particle behavior analysis apparatus 202a indicates the calculation conditions such as various physical parameters necessary for the calculation, the initial arrangement of the particles, and the number of particles to be analyzed necessary for various division methods, and the instruction input device 210 and the data input unit 220. And distribute the data to the related particle behavior analysis apparatus 202 (S104). At this time, the data input unit 220 and the division processing unit 250 simultaneously set the initial charge distribution such as a latent image on the photoconductor 10 and at the same time set the developer particles 102 (particularly in terms of the discharge analysis in relation to the discharge analysis). Particles) are set at the initial position (S106).

  The physical parameter is a set value used in a simulation calculation model, and particularly includes mesh data and various parameters necessary for the particle behavior analysis of the transfer process focused in the present embodiment. The mesh data means data obtained by dividing the analysis region of the transfer device 50 made of a dielectric or a resistor into minute regions, such as a difference mesh or a finite element mesh, according to a technique for performing electric field calculation. Various parameters include the Young's modulus of the structure (for example, the photoreceptor 10, the developing roll 140, and other developer particles 102 that function as a wall), the dielectric constant, conductivity, charge distribution, and boundary conditions of each member. Potential, the speed of the moving object, designation of the surface where charges can accumulate (referred to as charge surface), designation of the surface where discharge occurs, diameter and initial arrangement of developer particles 102 (carrier particles and toner particles) -Charge amount, dielectric constant, calculation step time, calculation end condition (simulation convergence condition), etc. are included.

  Next, the division processing unit 250 of the calculation management node arranges each particle behavior analysis device 202 (processor) identified in step S102 in each matrix element of the force matrix according to the force division method, and also analyzes each analysis target. Numbers are assigned to the particles (carrier particles and toner particles constituting the developer particles 102), and analysis target particles to be calculated are assigned to each processor associated with the matrix (S108). Each numbered processor (each particle behavior analysis device 202) is also called a node #N.

  Next, a plurality of types of inter-particle interaction forces are assigned to particles in a range according to the cutoff setting information that requires communication existing in the row direction and the column direction centered on itself in the force matrix. The numerical calculation processing unit 234 starts the particle behavior calculation process in a distributed manner to processors (particularly referred to as a specific processor). The cut-off means an analysis target limit value that is an index for limiting the target based on the distance in order to increase the calculation efficiency, instead of setting all particles in the analysis target range as actual analysis targets.

  For example, in-conductor charge transfer analysis processing unit 420 (dielectric constant analysis unit 422, charge analysis unit 424, charge transfer analysis unit 426) performs in-conductor charge transfer analysis processing (S120). Specifically, the dielectric constant analysis unit 422 performs dielectric constant distribution setting in consideration of toner particles (S122). The charge analysis unit 424 performs true charge distribution setting in consideration of the toner charge (S124). The charge transfer analysis unit 426 performs charge transfer in the conductor based on the dielectric constant distribution obtained by the dielectric constant analysis unit 422, the true charge distribution obtained by the charge analysis unit 424, and a preset dielectric polarization distribution. Calculation is performed (S126).

  Next, the discharge analysis unit 440 performs a discharge analysis using its own functional units (S140). For example, the counter-surface discharge extraction unit 442 performs a discharge segment pair extraction process in which discharge portions between parallel surfaces and discharge destinations are paired (S142). Here, in the discharge analysis processing according to the present embodiment, the inter-surface discharge extraction unit 442 performs a floating particle (hereinafter referred to as a floating particle) that is not deposited on the charge surface in the electric field of the analysis target region. ) Also has a feature in that it is subject to discharge analysis. This point will be described in detail later.

  The peak member discharge extraction unit 444 performs discharge segment pair extraction processing in which the discharge points between the peak members and the discharge destinations are grouped (S144). The discharge charge amount calculation unit 446 calculates the charge of all potential definition segments (S146). The charge update unit 448 updates the charge amount of the toner particles that have been discharged (S148).

  Next, the motion analysis unit 460 performs motion analysis of the analysis target particle. For example, the motion analysis unit 460 calculates the behavior of the toner after a lapse of a predetermined time, and updates the toner position obtained from the calculation result to the obtained position (S160). At this time, for the toner particles related to the discharge phenomenon, the toner particle information after the discharge analysis result (physical property information given to the toner particle reflecting the discharge analysis result) is changed between the toner particles in the analysis target region. It is made to be reflected in the calculation of interaction force between particles and other particles (for example, carrier particles) or walls.

  In addition, a plurality of types of interaction between many-body particles are calculated using different force matrices. For example, the magnetic interaction with the partner particle in the assigned matrix is analyzed using the force matrix for the magnetic interaction analysis. Next, communication is performed between specific processor cores, and the total value of magnetic interaction forces calculated by distributing the magnetic interaction is obtained. Similarly, the electrostatic interaction with the partner particle in the assigned matrix is analyzed using the force matrix for the electrostatic interaction analysis.

  Next, communication is performed between the specific processor cores, and the total value of electrostatic interaction forces calculated by distributing the electrostatic interaction is obtained. Further, the mechanical interaction (contact force) with the partner particle in the assigned matrix is analyzed using the force matrix for analyzing the mechanical interaction. Next, communication is performed between specific processor cores, and the total value of the mechanical interaction forces calculated by distributing the mechanical interaction is obtained.

  Furthermore, the sum total value calculated | required about each of a magnetic interaction, an electrostatic interaction, and a mechanical interaction (contact force) is added, and a total sum value is calculated | required. Next, using the total sum of the magnetic interaction, electrostatic interaction, and mechanical interaction (contact force), the equation of motion of each particle is solved and the position coordinates are calculated. Then, the position coordinates of each particle obtained in this way are sent (communication) to a specific processor core related to the interaction matrix, and the calculation information is updated.

  The charge transfer analysis unit 470 analyzes the charge transfer accompanying the movement of the object (S180).

  Thereafter, the process returns to step S120 and the same processing is repeated until the preset simulation end time (or the number of processing steps) is reached (S190).

  The bus interface unit 235 transfers the calculation data at each calculation step between the numerical calculation processing units 234 of the other particle behavior analysis apparatuses 202, and for each predetermined calculation step, the bus calculation unit 234 The calculation result output file is received and passed to the information presentation unit 240.

  The information presentation unit 240 aggregates data from each particle behavior analysis device 202, converts it into display data, and supplies it to the display device 212. In addition, the information presentation unit 240 outputs a simulation result file after a series of simulation processing is completed. For example, results such as potential distribution, charge amount distribution, toner behavior, toner charge distribution, and discharge distribution in the obtained calculation region are output.

  The display device 212 displays a processing result image based on the display data supplied from the information presentation unit 240. The behavior prediction of the developer particle 102 is visualized and displayed on the display device 212 so that the behavior of the developer particle 102 that is actually difficult to confirm can be visually grasped.

[Discharge analysis processing: basic concept]
The characteristic points (basic concept) in the discharge analysis processing of this embodiment are shown in FIG. 4A. Here, the discharge analysis processing of the present embodiment is also subject to discharge phenomenon analysis for particles that are not deposited on the charge surface and are floating (referred to as floating particles) in the electric field of the analysis target region (for example, the transfer region). It is characterized by the point. The analysis of the discharge phenomenon is also referred to as “performing discharge calculation”. By making floating particles that are not deposited on the charge surface also subject to discharge calculation, the accuracy of discharge calculation is improved as compared with the case where floating particles are not subject to discharge calculation.

  In this embodiment, in order to make suspended particles a target for discharge analysis, first, a region boundary (dividing an analysis target region sandwiched between charge surfaces according to a predetermined rule between opposing charge surfaces of the analysis target region ( A dividing line is set in the case of two dimensions, and a dividing plane is set in the case of three dimensions. Then, it is determined which side of the charge surface facing the suspended particle to be analyzed is located across the region boundary. The region to which the suspended particles belong is called the belonging region and includes the charge surface.

  And about the suspended particle which belongs to the belonging area | region of one surface side on both sides of a boundary, the discharge phenomenon between what belongs to the area | region of the other surface side (a charge surface is also included) is analyzed. Preferably, a discharge phenomenon between the charge surface on the attribution region side is also analyzed. The analysis of the discharge phenomenon relating to the charge surfaces and the deposited particles is performed in the same manner as in Patent Document 1. In summary, the suspended particles in the belonging region, the charge surface to which the suspended particle belongs, the suspended particle belonging to the opposite region (different region) across the region boundary, and the charged surface to which the suspended particle belongs are targeted. Analyze the discharge phenomenon. In short, in contrast to the mechanism of Patent Document 1, suspended particles are also subject to analysis of discharge phenomena.

  In addition, the method of setting the region boundary can be broadly divided into the concept defined from the geometric (physical distance) viewpoint and the concept defined from the electrical viewpoint. . This point will be described in detail in the first to third embodiments.

  Further, according to the study by the present inventor, it has been found that the accuracy of the discharge calculation is affected depending on which part of the particle is subjected to the discharge phenomenon analysis. For example, there is a clear difference between the case where the node located at the center (inside) of the particle is analyzed as a discharge search node and the case where the node located on the surface of the particle (surface layer portion) is analyzed as a discharge search node. It has been found that the surface is more realistic, that is, the surface improves the accuracy of the discharge calculation. This is presumably because charge distribution and discharge are present / generated on the material surface.

  Therefore, in this embodiment, the discharge phenomenon is analyzed for the surface (surface layer portion) of the particle. For example, the suspended particles in the region to which they belong (referred to as the belonging region), the charge surface to which the suspended particles belong, the suspended particles in the opposite region (different region) across the region boundary, and the suspended particles belong to The discharge phenomenon is analyzed for the charge surface on the side.

  As a method for analyzing the discharge phenomenon itself, a known method may be applied. In this embodiment, a discharge between the two surfaces is performed based on the potential distribution between the charge surfaces using the mechanism described in Patent Document 1. Extract possible locations where At that time, the region boundary is set as described above, and not only the deposited particles deposited on the charge surface, but also the floating particles, either surface side across the region boundary as in the embodiment described later. A discharge search node is given in consideration of whether it belongs to. As the charge amount with respect to the discharge search node, the charge amount of the particle is applied as it is. Alternatively, a value obtained by distributing the charge amount of the particles to the nodes included in the particles is applied to the charge amount for the discharge search node.

  For example, in FIG. 4A, when suspended particles a and b that are not deposited on the charge surfaces A and B exist in the analysis target region (particle motion region) sandwiched between the charge surfaces A and B arranged opposite to each other. The suspended particles a and b are the objects of discharge analysis. Therefore, first, the boundary setting unit 430 sets the boundary C (region boundary 610) in the analysis target region as in the first to third embodiments described later. A region on the charge surface A side across the region boundary 610 is referred to as a belonging region A, and a region on the charge surface B side is referred to as a belonging region B.

  Based on the region boundary 610 set by the boundary setting unit 430, the opposed inter-surface discharge extraction unit 442 has the suspended particles a to be analyzed located on either side of the charge surfaces A and B facing each other across the region boundary 610 (that is, belonging to It is determined whether it belongs to (region A or B). In this example, it is determined that the suspended particles a belong to the belonging region A and the suspended particles b belong to the belonging region B.

  Here, in the discharge analysis regarding the suspended particles, the main phenomenon to be analyzed is divided into the discharge phenomenon to be analyzed. The main phenomenon of the discharge phenomenon is to analyze the discharge phenomenon between the floating particles in the assigned region and the charge surface to which the floating particles do not belong or the deposited particles deposited on the charge surface. The discharge phenomenon that is subject to analysis is the discharge phenomenon between the floating particles in the assigned region, the discharge phenomenon between the charged surface to which the suspended particle belongs and the deposited particles deposited on the charge surface, or the discharge between the floating particles. It means analyzing the phenomenon.

  For example, as a discharge phenomenon to be analyzed as a main analysis target, for the suspended particle a belonging to the belonging region A, the discharge a1 between the suspended particle a and the charge surface B on the side to which the suspended particle a does not belong is analyzed. In “analyzing the discharge a1 between the floating particle a and the charge surface B”, for example, first, the difference between the electric potential of the charge surface B of the mesh-divided simulation model and the electric potential of the floating particle a (potential difference ΔVa1). Is calculated based on a predetermined charge amount before discharge and a dielectric constant defined by a simulation model. Then, it is determined whether or not the calculated potential difference ΔVa1 exceeds a discharge start voltage (for example, Paschen voltage) determined from the distance between the suspended particle a and the charge surface B.

  Similarly, for the suspended particle b belonging to the attribution region b, the discharge b1 between the suspended particle b and the charge surface A on the side to which the suspended particle b does not belong is analyzed as a main analysis target discharge phenomenon. In “analyzing the discharge b1 between the floating particle b and the charge surface A”, for example, first, the difference between the electric potential of the charge surface A of the mesh-divided simulation model and the electric potential of the floating particle b (potential difference ΔVb1). Is calculated based on a predetermined charge amount before discharge and a dielectric constant defined by a simulation model. Then, it is determined whether or not the calculated potential difference ΔVb1 exceeds a discharge start voltage (for example, Paschen voltage) determined from the distance between the suspended particle b and the charge surface A.

  As a discharge phenomenon to be analyzed, with respect to the suspended particles a belonging to the belonging region A, the discharge a2 between the suspended particles a and the charge surface A to which the suspended particles a belong is analyzed. In “analyzing the discharge a2 between the floating particle a and the charge surface A”, the potential of the charge surface A is similar to the case of “analyzing the discharge a1 between the floating particle a and the charge surface B”. The potential difference (potential difference ΔVa2) with respect to the floating particles a is calculated based on a predetermined charge amount before discharge and a dielectric constant defined by a simulation model. Then, it is determined whether or not the calculated potential difference ΔVa2 exceeds a discharge start voltage (for example, Paschen voltage) determined from the distance between the suspended particle a and the charge surface A.

  Similarly, for the suspended particles b belonging to the belonging region B, the discharge b2 between the suspended particles b and the charge surface B to which the suspended particles b belong is analyzed as a discharge phenomenon to be analyzed. In “analyzing the discharge b2 between the floating particle b and the charge surface B”, the potential of the charge surface B is the same as in the case of “analyzing the discharge b1 between the floating particle b and the charge surface A”. The potential difference (potential difference ΔVb2) between the floating particle b and the floating particle b is calculated based on a predetermined charge amount before discharge and a dielectric constant defined by a simulation model. Then, it is determined whether or not the calculated potential difference ΔVb2 exceeds a discharge start voltage (for example, Paschen voltage) determined from the distance between the suspended particle b and the charge surface B.

  Although not shown, in analyzing the discharge between one suspended particle and the other suspended particle, a difference (potential difference ΔVc2) between the potential of one suspended particle and the potential of the other suspended particle is determined in advance. Calculation is based on the amount of charge before discharge and the dielectric constant defined by the simulation model. Then, it is determined whether or not the calculated potential difference ΔVc2 exceeds a discharge start voltage (for example, Paschen voltage) determined from the distance between the suspended particle b and the charge surface B.

  For the discharge analysis between the charge surfaces A and B and the discharge analysis for the deposited particles deposited on the charge surfaces A and B, for example, a well-known analysis method such as the mechanism described in Patent Document 1 is similarly applied. You can do it.

  This will be specifically described below. In the following, the discharge analysis process (especially how to provide a discharge search node) in the discharge analysis unit 440 different from the mechanism described in Patent Document 1 will be noted, and the other dielectric constant analysis unit 422, charge analysis unit 424, Detailed descriptions of the charge transfer analysis unit 426, the motion analysis unit 460, and the charge transfer analysis unit 470 are omitted.

<Discharge Analysis Processing: First Embodiment>
FIG. 5 is a diagram for explaining the discharge analysis process of the first embodiment.

  The discharge analysis process of the first embodiment is based on the basics of the above-described discharge analysis process, and further, in terms of where the dividing line is set, the geometrical relationship between two opposing boundaries (charge planes). This method is characterized in that an intermediate position is used as a region boundary 610 (a dividing line when considered in two dimensions, a dividing surface when considered in three dimensions). Another feature is that a discharge analysis is performed between the non-deposited particles floating between the opposing surfaces and the charge surface to which the particles do not belong. This concept is processing in which the spatial intermediate position is regarded as being coincident with the electrical intermediate position (the midpoint of the potential between the discharge node pair). FIG. 5 is shown in two dimensions for ease of understanding.

  For example, attention is paid to the analysis in the primary transfer region where the photoconductor 10 and the intermediate transfer belt 58 face each other. In this case, the photoconductor 10 and the intermediate transfer belt 58 correspond to the opposite charge surfaces, the charge surface on the photoconductor 10 side is the charge surface 602, and the charge surface on the intermediate transfer belt 58 side is the charge surface 604. This case is equivalent to paying attention to the analysis in the transfer region where the photoreceptor 10 and the sheet face each other in the image forming apparatus 1 that does not employ the intermediate transfer method. In this case, the photoconductor 10 and the paper correspond to the opposite charge surfaces, the charge surface on the photoconductor 10 side may be the charge surface 602, and the charge surface on the paper side may be the charge surface 604. Further, the analysis is not limited to the analysis in the primary transfer area, but may be the case in the analysis in the secondary transfer area formed by the secondary transfer apparatus 50b. In this case, the intermediate transfer belt 58 and the paper correspond to the opposite charge surfaces, the charge surface on the intermediate transfer belt 58 side may be the charge surface 602, and the charge surface on the paper side may be the charge surface 604.

  When performing a simulation in which toner particles are deposited on the charge surface, in a portion where the toner particles are deposited, a node located on the outermost layer portion of the toner particle is used as a discharge search node instead of a node on the charge surface. To do. In addition, toner particles floating in a space sandwiched between both charge surfaces 602 and 604, not in the accumulated state, are also charged with the charge surface 602 side from the region boundary 610. A discharge search node is set for the toner particle according to which region on the surface 604 side belongs, and a discharge analysis between the charge surfaces 602 and 604 is also performed.

  Hereinafter, the toner particles in a deposited state are referred to as deposited particles, and the toner particles in a suspended state (not deposited) are referred to as suspended particles. The toner particles are assumed to be spheres and are displayed as circles in the drawing.

[About sediment particles]
For deposited particles, discharge search nodes are extracted by the same method as in paragraphs 69 to 71 of Patent Document 1. For example, the counter-surface discharge extraction unit 442 performs the following processing.

  1) All nodes on the charge surface are registered as discharge search nodes.

  2) Toner particles located on the surface among the toner particles deposited on the charge surfaces 602 and 604 are extracted. For example, in the figure, toner particles indicated by black circles are those deposited on the photoreceptor 10 side. Toner particles indicated by white circles are those deposited on the charge surface 604 side. The toner particles indicated by satin and the toner particles indicated by hatching are floating particles. The discharge surface of toner particles (black circles) deposited on the photoreceptor 10 side becomes a charge surface 602, and the discharge surface of toner particles (white circles) deposited on the intermediate transfer belt 58 side becomes a charge surface 604.

  3) Of the nodes on the surface of each toner particle, the node closest to the position farthest from the charge surfaces 602 and 604 is extracted as a toner node. Then, the extracted toner node is added as a discharge search node.

[About suspended particles]
For suspended particles, discharge search nodes are extracted by the following method. For example, the counter-surface discharge extraction unit 442 performs the following processing.

  1) In order to examine whether the charge particle 602 or the charge surface 604 belongs to the suspended particle, the boundary setting unit 430 is an example of the region boundary 610 at a geometric intermediate position between the charge surfaces 602 and 604. The first spatial discharge dividing line 612 is set. It is only necessary to set the first spatial discharge dividing line 612 at a geometric intermediate position between the charge surfaces 602 and 604. Since the first spatial discharge dividing line 612 can be obtained only by distance calculation, the setting is simple. The calculation time is shortened compared with the setting method of the region boundary 610 to which this embodiment is not applied.

  2) The inter-surface discharge extraction unit 442 uses the information of the first spatial discharge dividing line 612 set by the boundary setting unit 430, and the center coordinates of the suspended particles are based on the first spatial discharge dividing line 612. In addition, the discharge surface to which the suspended particles belong is determined depending on which of the charge surface 602 and the charge surface 604 is closer. Specifically, the center of the suspended particle from the first spatial discharge dividing line 612 is the charge surface 602 and the discharge surface of the particle on the charge surface 602 side is the center of the suspended particle from the first spatial discharge dividing line 612. The discharge surface of the particle on the charge surface 604 side is the charge surface 604.

  3) According to paragraphs 69 to 70 of Patent Document 1, the inter-surface discharge extracting unit 442 is located at a position farthest from the charge surfaces 602 and 604 on the side to which it belongs, among the nodes on the surface of each particle including suspended particles. The closest node is extracted as a particle node, and the extracted particle node is added as a discharge search node. Even when there are a plurality of nodes on the target suspended particles, the nodes on the side close to the surface (that is, located on the surface layer portion of the particles) and on the opposite side of the surface to which the suspended particles belong are charged surfaces 602 and 604. Adjacent nodes are extracted as discharge search nodes for potential difference calculation.

  As a result, the node belonging to the floating particle closest to the intersection on the region boundary 610 (first spatial discharge dividing line 612) between the normal (mesh line) to the node on the charge surfaces 602 and 604 and the suspended particle is the charge surface. Instead of the nodes on 602 and 604, discharge candidate nodes are used. As a result, suspended particles not deposited on the charge surfaces 602 and 604 are also subject to discharge calculation.

[Others]
1) Nodes on the charge surfaces 602 and 604 covered with deposited particles are excluded from discharge search nodes.
2) A discharge node pair is extracted based on the discharge search nodes extracted as described above.

  3) Then, a discharge analysis is performed between the discharge search node set for the suspended particle and the discharge search node belonging to the charge surface to which the suspended particle does not belong. For example, regarding the discharge search node belonging to the region on the charge surface 602 side of the suspended particles, the discharge search node belonging to the region on the charge surface 604 side (the discharge search node set on the charge surface 604 or the charge search node 604 is deposited. The discharge phenomenon is analyzed with respect to the discharge search node set for the deposited particles. In addition, regarding the discharge search node belonging to the region on the charge surface 604 side of the suspended particles, the discharge search node belonging to the region on the charge surface 602 side (the discharge search node set on the charge surface 602 or the charge search node 602 is deposited. The discharge phenomenon is analyzed with respect to the discharge search node set for the deposited particles.

  Note that the method of the discharge analysis itself may be the same as that of Patent Document 1. Here, the detailed explanation is omitted.

<Discharge Analysis Processing: Second Embodiment>
FIG. 6 is a diagram for explaining the discharge analysis process of the second embodiment. Here, FIG. 6 (1) is a diagram for explaining the comparison between the first and second embodiments, and FIG. 6 (2) is a diagram for explaining the details of the technique of the second embodiment.

  The discharge analysis process according to the second embodiment is based on the basics of the above-described discharge analysis process, and in addition to depositing not only two opposing boundaries (charge planes), but also where to set the dividing line. A feature is that a geometrical intermediate position including the amount of particles is used as the region boundary 610. This is intended to take into account the substantial fluctuation of the charge surface due to the presence of deposited particles on the charge surfaces 602 and 602. Further, as in the first embodiment, there is a feature in that a discharge analysis is performed between a non-deposited particle floating between opposed surfaces and a charge surface to which the particle does not belong. FIG. 6A is also shown in two dimensions for easy understanding.

  “In consideration of the amount of deposited particles” means that the region boundary 610 is obtained by replacing the position of the charge surface with the surface position of the deposited particles where the deposited particles exist. Similar to the first embodiment, this concept is a process in which the spatial intermediate position is regarded as coincident with the electrical intermediate position.

  As shown in FIG. 6 (1), deposited particles are present on the charge surface 604 side, and the deposited particle surface line 622 in the figure is the approximate position of the outermost surface (charge surface 602 side) of the deposited particles. Is shown. At this time, when the method of setting the first spatial discharge dividing line 612 is applied as in the first embodiment, the first spatial discharge dividing line 612 is set. In this method, although the setting of the first spatial discharge dividing line 612 is simple, as shown in FIG. 6A, when the deposited particles exceed the first spatial discharge dividing line 612, the deposited particles and the particles D The accuracy of the discharge calculation for is lost.

  Therefore, in the second embodiment, in the place where the deposited particles exist, this problem is solved by obtaining the region boundary 610 by replacing the position of the charge surface with the surface position of the deposited particles. For example, the counter-surface discharge extraction unit 442 performs the following processing.

  1) For the deposited particles, a discharge search node is extracted by the same method as in the first embodiment.

  2) A normal line 624 with respect to the charge surface 604 is drawn in the direction of the charge surface 602, and discharge search nodes belonging to the charge surfaces 602 and 604 closest to each normal line 624 are extracted. These two discharge search nodes are called discharge node pairs. Incidentally, the line (mesh line, element boundary) and the normal line 624 when dividing the mesh are independent (see FIG. 6B). The node closest to the intersection of the normal line 624 and the charge surfaces 602 and 604 is the discharge search node. If there is an intersection between the normal line 624 and the particle surface, the node closest to this is set as the discharge search node.

  3) Thereafter, the first spatial discharge dividing line 612 is set by obtaining the midpoint of the distance between the discharge node pairs. In other words, the second spatial discharge dividing line 614 taking into account the effect of the deposited particles is set at a geometric intermediate position between the discharge search node belonging to the charge surface 602 and the discharge search node belonging to the charge surface 604.

  “Discharge search nodes belonging to the surface” is described in order to “include the amount of deposited particles”, so that not only the discharge search nodes on the charge surfaces 602 and 604 but also the discharge search nodes specified for the deposited particles are targeted. And is based on that.

  In the example of FIG. 6A, the second spatial discharge dividing line 614 is set at a geometric intermediate position between the charge surface 602 and the deposited particle surface line 622, and the generated deposited particles can be generated. The accuracy of the discharge calculation with respect to is improved compared to the method of the first embodiment.

  2) to 3) will be described in detail with reference to FIG.

[Rules for drawing normals]
The mesh line and the normal line 624 are independent, and for example, as shown in FIG. This perpendicular is defined as a normal 624.

[Discharge search node extraction]
1) Normal 624A: A normal 624 focused on the deposited particles on the charge surface 602 side (for example, A in the figure) is referred to as a normal 624A. The boundary setting unit 430 obtains an intersection (small black circle in the figure) with the deposited particle (toner particle) closest to the charge surface 604 side on the charge surface 602 side. Next, the node closest to the obtained intersection is examined. In the illustrated example, the star a1 on the right of the small black circle is selected. Then, the star a2 in the figure is selected as the discharge search node belonging to the charge surface 604 with respect to the normal 624A. As a result, for the normal 624A, the discharge search node belonging to the charge surface 602 is the star a1, the discharge search node belonging to the charge surface 604 is the star a2, and the two discharge search nodes a1 and a2 are related to the normal 624A. It becomes discharge node pair a.

  2) Normal line 624B: A normal line 624 focusing on deposited particles on the charge surface 604 side (for example, B in the figure) is referred to as a normal line 624B. The boundary setting unit 430 obtains an intersection (small black circle in the figure) with the deposited particle (toner particle) closest to the charge surface 602 side on the charge surface 604 side. Next, the node closest to the obtained intersection is examined. In the example in the figure, the star b1 at the lower right of the small black circle is selected. Then, the triangle b2 in the figure is selected as the discharge search node belonging to the charge surface 602 with respect to the normal line 624B. As a result, regarding the normal 624B, the discharge search node belonging to the charge surface 604 is the star b1, the discharge search node belonging to the charge surface 602 is the triangle b2, and the two discharge search nodes b1 and b2 are related to the normal 624B. It becomes a discharge node pair b.

  3) The boundary setting unit 430 identifies the discharge node pair for each normal 624 by performing the same processing as 1) and 2) for the normal 624 at other positions in the same manner.

  4) The boundary setting unit 430 sets a geometric intermediate position of each discharge node pair as a geometric discharge division point. For example, for the normal 624A, the point a3 is a geometric discharge division point, and for the normal 624B, the point b3 is a geometric discharge division point. The boundary setting unit 430 identifies the second spatial discharge dividing line 614 by connecting the geometric discharge dividing points obtained from the plurality of normal lines 624.

  5) Hereinafter, the same as in the first embodiment.

<Discharge Analysis Processing: Third Embodiment>
7 to 7A are diagrams for explaining the discharge analysis processing of the third embodiment.

  The discharge analysis process according to the third embodiment is based on the basics of the above-described discharge analysis process, and further uses an electrical intermediate position as the region boundary 610 in terms of where to set the dividing line. There are features. Further, as in the first and second embodiments, a feature is that a discharge analysis is performed between a non-deposited particle floating between opposing surfaces and a charge surface on the side to which the particle does not belong. is there. The third embodiment is an example of dealing with a case where the spatial intermediate position does not coincide with the electrical intermediate position. The following description is based on the second embodiment, but the same technique can be applied to the first embodiment.

  For example, in the first and second embodiments, the region boundary 610 is set based on the spatial intermediate position on the assumption that the spatial intermediate position coincides with the electrical intermediate position. However, for example, when uncharged particles having a charge (floating particles) exist between the discharge node pairs or when the charge distribution on the charge surfaces 602 and 604 is not uniform, FIG. ), The potential gradient between the discharge node pairs is not constant. In this case, the spatial intermediate position and the electrical intermediate position do not coincide with each other, and the accuracy of the discharge calculation is lowered.

  Therefore, in the third embodiment, this problem is solved by actually specifying the electrical intermediate position. For example, the counter-surface discharge extraction unit 442 performs the following processing.

  1) First, according to 1) to 3) in the second embodiment, a discharge node pair for each normal 624 is specified.

  2) Next, regarding the discharge node pair of interest, the state of the potential between the discharge node pairs is specified. For example, in the finite element method applied in the present embodiment, since the potential is defined as the value of a node, for example, as in Patent Document 1, the potential of each intersection (node) of the mesh line between the discharge node pairs is defined. What is necessary is just to specify an electric potential curve from. That is, the discharge search node belonging to the charge surface 602 specified by applying the second embodiment and the discharge search node belonging to the charge surface 604 exist on the mesh line, and from the potential of each node between both discharge search nodes, The potential curve between the discharge node pairs is specified. Then, a point that is the midpoint potential ((Va + Vb) / 2) of the potentials of both discharge search nodes (Va and Vb: Va> Vb) may be set to an electrical intermediate position.

  3) The boundary setting unit 430 specifies the electrical intermediate position for each discharge node pair by performing the process of 2) in the same manner for the discharge node pairs at other positions.

  4) The boundary setting unit 430 identifies the electrical discharge dividing line 616 by connecting the electrical intermediate positions obtained for the plurality of discharge node pairs (see FIG. 7B).

  5) The following is the same as in the first and second embodiments.

  As shown in FIG. 7 (3), it is preferable to perform the discharge analysis even when the potential change state (potential curve) between the discharge node pairs is not monotonous (monotonic increase or monotonic decrease). I understood that it was not (does not match the actual situation). Therefore, when the potential curve between the discharge search pairs to be analyzed is not monotonically increasing or monotonically decreasing, the opposed inter-surface discharge extracting unit 442 excludes (does not discharge) the target from the discharge analysis. Since the method of the first and second embodiments is not a method of specifying the state of the potential curve between the discharge node pairs, such a countermeasure cannot be performed. Also in this respect, it can be said that the third embodiment is a more effective technique than the techniques of the first and second embodiments.

  FIG. 7 (2) shows a modification to the second embodiment, and the charge distribution on the charge surface 604 is not uniform due to the presence of the deposited particles (on the charge surface 604 side in the figure), so that there is a gap between the discharge node pairs. However, the reason why the potential gradient between the discharge node pairs is not constant is not limited to this case.

  For example, as shown in FIG. 7A (1), the potential distribution (electric field distribution) is not uniform due to the presence of floating particles regardless of whether or not the deposited particles are present on the charge surfaces 602 and 604. Therefore, in an extreme case, when floating particles exist between the discharge node pairs of interest, the potential gradient between the discharge node pairs is not constant. Of course, even when there are no suspended particles between the pair of discharge nodes of interest, if there are suspended particles with electric charges nearby, the potential gradient between the discharge node pairs is constant under the influence of the suspended particles. Is not. Even in such a case, the electric discharge dividing line 616 is set by reflecting the change caused by the suspended particles E floating in the analysis target region with respect to the electric field between the charge surface 602 and the charge surface 604. Rather than setting the geometric intermediate position to the region boundary 610 (spatial discharge dividing line 612, 614), setting the electrical intermediate position to the region boundary 610 (electrical discharge dividing line 616) is an analysis. Accuracy is improved.

  Incidentally, in the case of an unstructured grid, instead of specifying the potential state between the discharge node pairs, the potential state on each normal line 624 may be specified from each node around the normal line. In this case, processing is preferably performed as shown in FIG. 7A (2). For example, a dotted line in the figure is a normal 624 and a square is an element. Triangular points are formed on the normal line 624 from the charge surface 602 side to the charge surface 604 side at an interval sufficiently smaller than the node interval.

  Then, for each triangular point, the potential of the nearest node is given as the potential of the triangular point. For example, a white triangle in the figure is given the potential indicated by a circle in the figure, which is the closest node. A potential is obtained by the same method for other triangular points, and a triangular point closest to the electrical middle point is set as an electrical intermediate position with respect to the normal 624.

  The boundary setting unit 430 specifies the electrical intermediate position with respect to each normal 624 by performing the same with respect to the normals 624 at other positions. The boundary setting unit 430 identifies the electrical discharge dividing line 616 by connecting the electrical intermediate positions obtained with respect to the plurality of normals 624 (see FIG. 7B).

  Note that the potential on the normal line 624 may be obtained by interpolating from the potential of the element through which the normal line 624 passes. For example, a triangular point is hit on the normal 624. Since each triangular point is always included in the element, the potential at the position of the triangular point can be obtained by linearly interpolating the potential of the element from the position of the triangular point in the element.

<Discharge Analysis Processing: Fourth Embodiment>
FIG. 8 is a diagram for explaining the discharge analysis process of the fourth embodiment.

  The discharge analysis process of the fourth embodiment is based on the basics of the above-described discharge analysis process, and further performs a discharge analysis between the suspended particles and the charge surfaces 602 and 604 on the side to which the suspended particles belong. The point is to do.

  In the discharge analysis processing of the first to third embodiments described above, since the discharge analysis is performed between the floating particles between the opposing surfaces and the charge surface to which the floating particles do not belong, the floating particles and the particles are Discharge analysis between the surface to which it belongs and between suspended particles is not performed. However, depending on the potential difference, the spatial distance, etc., there is a possibility of discharging even in such a positional relationship.

  The fourth embodiment is an example of dealing with such a case, and the discharge between the floating particles (the surface thereof) not deposited on the charge surfaces 602 and 604 and between the charge surfaces 602 and 604 on both sides or between the floating particles. Analyze. In other words, the fourth embodiment is a mechanism that takes into account the discharge from the suspended particles of interest to the boundary on both sides, the deposited particles, and other suspended particles other than itself. By discharging the floating particles to the charge surfaces 602 and 604 on both sides and other particles (deposited particles and floating particles), the accuracy of the discharge calculation is improved as compared with the first to third embodiments.

  As a basic idea, the inter-surface discharge extraction unit 442 performs a discharge analysis between the surface layer portion on the charge surface 602 side of the center of the suspended particles and the one belonging to the charge surface 602, and from the center of the suspended particles. In addition, the discharge analysis is performed between the surface layer portion on the charge surface 604 side and the member belonging to the charge surface 604. For this reason, for example, the inter-surface discharge extracting unit 442 obtains the discharge search node as follows.

  1) As for the deposited particles, as described in the first embodiment, discharge search nodes are extracted by the same method as paragraphs 69 to 71 of Patent Document 1.

  2) With respect to suspended particles, all nodes in the suspended particles are examined, and nodes close to the charge surface 602 are selected as discharge search nodes belonging to the charge surface 604, and conversely, nodes close to the charge surface 604 are selected. A discharge search node belonging to the charge surface 602 is selected.

  At this time, a method as shown in FIG. 8 may be adopted in order to easily determine which node of the charge surfaces 602 and 604 is closest to. That is, a straight line passing through the center coordinates of the suspended particle and parallel to the charge surface 604 is drawn to each suspended particle, and the straight line is defined as a particle dividing line 618 for the suspended particle. For each suspended particle, a node closer to the charge surface 602 side than the particle dividing line 618 belongs to the charge surface 604, and a node closer to the charge surface 604 side belongs to the charge surface 602.

  3) With respect to the discharge search node (node on the surface layer side close to the charge surface 604) which is supposed to belong to the charge surface 602 side, the discharge calculation with the charge surface 604 is performed, and the charge search node belongs to the charge surface 604 side. With respect to the discharge search node (node on the surface layer side close to the charge surface 602), the discharge calculation with the charge surface 602 is performed. Moreover, you may make it perform the discharge calculation between floating particles.

  By adopting such a method, the discharge search node belonging to the region on the charge surface 602 side of the floating particle and the discharge search node (charge) belonging to the region on the charge surface 604 side in the same way as in the first to third embodiments. The method of analyzing the discharge phenomenon between the discharge search node set on the surface 604 and the discharge search node set for the deposited particles deposited on the charge surface 604 may be applied as it is. Further, the discharge search nodes belonging to the region on the charge surface 604 side of the suspended particles and the discharge search nodes belonging to the region on the charge surface 602 side (discharge search nodes set on the charge surface 602 and deposited particles deposited on the charge surface 602) It is also possible to apply the technique of analyzing the discharge phenomenon with respect to the discharge search node set with respect to the above as it is.

<Particle behavior analyzer; computer configuration>
FIG. 9 is a block diagram illustrating another configuration example of the particle behavior analysis apparatus 202. This configuration uses an electronic computer such as a personal computer constructed from a microprocessor or the like that executes software, and shows a more realistic hardware configuration of the particle behavior analysis apparatus 202 that performs particle behavior analysis.

  For example, a computer system including a CPU (Central Control Unit), a ROM (Read Only Memory) that is a read-only storage unit, or a RAM (Random Access Memory) that is a memory that can be read / written as needed FIG. 3 is a system configuration diagram for performing particle behavior analysis processing by software processing.

  That is, in this embodiment, the mechanism for analyzing the behavior of particles is not limited to being configured by a hardware processing circuit, but is realized by software using a computer (computer) based on a program code that realizes the function. It is also possible. Therefore, a program suitable for realizing the mechanism according to the present embodiment by software using an electronic computer (computer) or a computer-readable recording medium (storage medium) storing this program is extracted as an invention. By adopting a mechanism that is executed by software, the calculation process procedure of the particle behavior analysis can be easily changed without changing the hardware of the existing computer system.

  A series of particle behavior analysis processing can be realized not only by hardware or software alone but also by a combined configuration of both. When executing processing by software, a program showing the processing procedure is installed (installed) in a storage medium in a computer embedded in hardware and executed, or a general-purpose electronic computer capable of executing various types of processing is used. Incorporate and execute the program.

  A program for causing a computer to execute the particle behavior analysis processing function is distributed and provided through, for example, a portable recording medium. For example, the program may be distributed and provided by being stored on a CD-ROM (Compact Disc Read Only Memory) or FD (flexible disc). Also, an MO (Magneto Optical Disk) drive may be provided to store the program in the MO, and the program may be stored in another recording medium such as a card-type storage medium using a non-volatile semiconductor memory such as a flash memory. It may be stored and distributed / provided.

  The program constituting the software is not limited to being distributed / provided via a recording medium, but may be distributed / provided via communication means (wired / wireless is not required). For example, the program may be obtained by downloading or updating from another server via a network such as the Internet.

  The program is provided as a file describing a program code that realizes the function of performing particle behavior analysis processing. In this case, the program is not limited to being provided as a batch program file, and the hardware configuration of a system configured by a computer Depending on the case, it may be provided as an individual program module.

  For example, the computer system 900 includes a controller unit 901 and a recording / reading control unit 902 for reading and recording data from a recording medium such as a hard disk device, an FD drive, a CD-ROM drive, and a semiconductor memory controller. .

  In addition, the computer system 900 includes an operation unit 903 as a functional unit that forms a user interface, and an interface unit 909 (IF unit) that performs an interface function between the functional units. Note that an image forming unit that outputs the processing result to an output medium (for example, printing paper) may be provided so that the analysis processing result is printed out and presented to the user.

  The controller unit 901 includes a CPU 912, a ROM 913 that is a read-only storage unit, a RAM 915 that is an example of a volatile storage unit that can be written and read at any time, and a RAM (NVRAM) that is an example of a nonvolatile storage unit. 916).

  The operation unit 903 is for accepting an operation by an operator or for providing various types of information with a display device. As an instruction input device of the operation unit 903, for example, an operation key on the operation panel may be used, or a keyboard, a mouse, or the like may be used. As a display device of the operation unit 903, for example, an operation panel may be used, or another display unit such as a CRT or LCD may be used. In addition, by setting it as the display part which has a touchscreen on a display surface, it is good also as a structure which inputs information not only with a display but with a fingertip or a pen.

  The interface unit 909 includes, for example, a communication IF unit 999 that mediates transfer of communication data with a network in addition to a system bus 991 that is a transfer path of processing data and control data.

  The communication IF unit 999 performs data transmission / reception with another computer system 900 by being connected to an external network such as the Internet, LAN, and WAN. Thus, by applying a predetermined division method and executing parallel processing by cooperative processing of a plurality of computer systems 900, the analysis time is shortened. Although not shown, the interface unit 909 includes, for example, a printer IF unit that functions as an interface with an image forming unit and other printers.

  The recording / reading control unit 902 is configured to be removable from a portable external recording medium such as a CD-ROM or a memory card, and has a function of an external data reading unit that reads information from the portable external recording medium.

  By providing the recording / reading control unit 902 (external data reading unit), the program can be installed or updated from an external recording medium. By including the communication IF unit 999, the program can be installed or updated via the communication network.

  With such a configuration, the particle behavior analysis program is stored in the RAM 915 from a readable recording medium such as a CD-ROM in which a program for executing the particle behavior analysis processing is stored in accordance with an instruction from the operator via the operation unit 903. The particle behavior analysis program is activated by an instruction or automatic processing by an operator via the operation unit 903.

  The CPU 912 controls the entire system via the system bus 991 and performs calculation processing associated with the particle behavior analysis method according to the particle behavior analysis program. The ROM 913 stores a control program for the CPU 912 and the like. The RAM 915 is configured by SRAM, flash memory, or the like, and stores program control variables, data for various processes, and the like. The RAM 915 includes an area for temporarily storing data obtained by calculation according to an application program, data obtained from the outside, and the like. The processing result is stored in a storage device such as a RAM 915 or a hard disk, and information on the processing result is output to an operation panel, a display device such as a CRT or LCD.

  Here, the control configuration of the particle behavior analysis apparatus 202 is described as a configuration example that is realized by software on a computer. However, each part (functional block) of the control configuration for realizing the particle behavior analysis of the present embodiment. The specific means (including the above) may be hardware, software, communication means, a combination thereof, or other means, and this is obvious to those skilled in the art. Moreover, the functional blocks may be combined and integrated into one functional block. Also, software that causes a computer to execute program processing can be distributed and installed as individual program modules according to the combination of hardware, communication means, and the like.

  For example, a processing circuit 908 may be provided in which not all processing of each functional part for particle behavior analysis processing is performed by software, but a part of these functional parts is performed by dedicated hardware. Although the mechanism performed by software can flexibly cope with parallel processing and continuous processing, the processing time becomes longer as the processing becomes complicated, so that a reduction in processing speed becomes a problem. On the other hand, when constructed with a hardware processing circuit, even if the process is complicated, a reduction in processing speed can be prevented, and an accelerator system capable of achieving high throughput can be constructed.

  For example, as the processing circuit 908, a data receiving unit 908 a corresponding to the data receiving unit 232 and a numerical operation processing unit 908 b corresponding to the numerical operation processing unit 234, respectively, constituting the data processing unit 230 shown in FIGS. 3 to 3B. Any one of the output data processing unit 908c corresponding to the functional part of the output data processing unit of the bus interface unit 235 and the division processing unit 908x corresponding to the division processing unit 250 may be configured by hardware.

  DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 10 ... Photoconductor, 20 ... Charging apparatus, 30 ... Exposure apparatus, 40 ... Developing apparatus, 50 ... Transfer apparatus, 58 ... Intermediate transfer belt, 60 ... Cleaning apparatus, 70 ... Fixing apparatus, 102 ... Development Agent particle 200 ... Particle behavior analysis system 202 ... Particle behavior analysis device 202a ... Main particle behavior analysis device 202b ... Secondary particle behavior analysis device 204 ... Information output device 210 ... Instruction input device 212 ... Display device 220 ... Data input unit, 230 ... Data processing unit, 232 ... Data reception unit, 234 ... Numerical calculation processing unit (particle behavior calculation unit), 238 ... Data storage unit, 240 ... Information presentation unit, 250 ... Division processing unit, 402 ... Discharge phenomenon analysis device 420. Conductor charge transfer analysis processing unit 422. Dielectric constant analysis unit 424 Charge analysis unit 426 Charge transfer analysis unit 430 Boundary setting 440 ... Discharge analysis unit 442 ... Inter-surface discharge extraction unit 444 ... Point member discharge extraction unit 446 ... Discharge charge amount calculation unit 448 ... Charge update unit 460 ... Motion analysis unit 470 ... Charge Movement analysis unit, 602, 604 ... charge plane, 610 ... region boundary, 612 ... first spatial discharge dividing line, 614 ... second spatial discharge dividing line, 616 ... electrical discharge dividing line, 618 ... particle dividing line

Claims (15)

A boundary setting unit for setting a boundary between the first surface and the second surface in the analysis target region sandwiched between the first surface and the second surface ;
Among the particles floating in the analysis target region, those belonging to the first surface side region across the boundary set by the boundary setting unit belong to the second surface side region. Analyzing the discharge phenomenon between them and those belonging to the region on the second surface side across the boundary set by the boundary setting unit are those belonging to the region on the first surface side A discharge analysis unit for analyzing the discharge phenomenon between
Discharge phenomenon analysis device equipped with. The discharge phenomenon analyzing apparatus according to claim 1 , wherein the boundary setting unit sets a geometric intermediate position between the first surface and the second surface as the boundary. In the case where particles having an electric charge are deposited on the first surface and the second surface, the boundary setting unit includes the uppermost particle among the deposited particles, The discharge phenomenon analyzing apparatus according to claim 1 , wherein a geometric intermediate position between a particle facing a particle and a particle deposited on the surface facing the uppermost layer is set as the boundary. . The discharge phenomenon analyzing apparatus according to claim 3 , wherein the boundary setting unit sets a geometric intermediate position to the boundary based on a surface of the uppermost particle among the deposited particles. The discharge phenomenon analyzing apparatus according to claim 1 , wherein the boundary setting unit sets an electrical intermediate position between the first surface and the second surface as the boundary. In the case where particles having an electric charge are deposited on the first surface and the second surface, the boundary setting unit includes the uppermost particle among the deposited particles, The discharge phenomenon analyzing apparatus according to claim 5 , wherein an electrical intermediate position between a particle facing the existing particle or an uppermost particle among the particles deposited on the facing surface is set as the boundary. The boundary setting unit is configured for the first surface and the electric field between the second surface, said to reflect the change due to particles suspended in the analysis target area for setting the boundaries claim 5 or 6. The discharge phenomenon analyzing apparatus according to 6 . The discharge phenomenon analyzing device according to any one of claims 5 to 7 , wherein the discharge analysis unit excludes the discharge search point from the object of discharge analysis when the potential change at the discharge search point of interest is not monotonous. . The discharge analysis unit analyzes a discharge phenomenon between the floating particles belonging to the first surface side region and those belonging to the first surface side region. and, in any one of claims 1-8 for analyzing a discharge phenomenon between the ones belonging to further the second surface areas for those belonging to the area of the second surface The described discharge phenomenon analyzer. The discharge analysis unit
Dividing the particles floating in the analysis target region into a portion on the first surface side and a portion on the second surface side,
For those belonging to the region on the first surface side across the boundary set by the boundary setting unit, the portion belonging to the first surface side and the region belonging to the region on the first surface side The discharge phenomenon between
For those belonging to the region on the second surface side across the boundary set by the boundary setting unit, the portion belonging to the second surface side and the region belonging to the region on the second surface side The discharge phenomenon analysis apparatus according to claim 9 , wherein the discharge phenomenon is analyzed. The discharge analysis unit analyzes a discharge phenomenon between the surface on the first surface side of the particles floating in the analysis target region and the one belonging to the region on the first surface side, discharge according to claim 9 or 10 for analyzing a discharge phenomenon between the belonging analyzed area on the second surface side of the surface of the floating to have particles on the second surface side of the region Phenomenon analysis device. The discharge phenomenon analysis apparatus according to claim 1, wherein the discharge analysis unit analyzes a discharge phenomenon that occurs on a surface of particles floating in the analysis target region. A boundary setting unit for setting a boundary between the first surface and the second surface in the analysis target region sandwiched between the first surface and the second surface ;
Among the particles floating in the analysis target region, those belonging to the first surface side region across the boundary set by the boundary setting unit belong to the second surface side region. Analyzing the discharge phenomenon between them and those belonging to the region on the second surface side across the boundary set by the boundary setting unit are those belonging to the region on the first surface side A discharge analysis unit for analyzing the discharge phenomenon between
Based on the physical property information of the particles after the analysis result of the discharge phenomenon by the discharge analysis unit, a motion analysis unit that analyzes the motion of each particle present in the analysis target region;
Particle behavior analysis device equipped with. A receiving unit that receives the distributed analysis target element, and a plurality of particle behavior calculation units that perform particle behavior calculation according to a predetermined parallel processing division method based on physical property information of the analysis target particle received by the receiving unit;
A distribution processing unit that distributes the analysis target element within the analysis target range to each of the plurality of particle behavior analysis devices according to the division method;
With
The particle behavior calculator
A boundary setting unit for setting a boundary between the first surface and the second surface in the analysis target region sandwiched between the first surface and the second surface ;
Among the particles floating in the analysis target region, those belonging to the first surface side region across the boundary set by the boundary setting unit belong to the second surface side region. Analyzing the discharge phenomenon between them and those belonging to the region on the second surface side across the boundary set by the boundary setting unit are those belonging to the region on the first surface side A discharge analysis unit for analyzing the discharge phenomenon between
Based on the physical property information of the particles after the analysis result of the discharge phenomenon by the discharge analysis unit, a motion analysis unit that analyzes the motion of each particle present in the analysis target region;
Particle behavior analysis system equipped with A boundary setting unit for setting a boundary between the first surface and the second surface in the analysis target region sandwiched between the first surface and the second surface ;
Among the particles floating in the analysis target region, those belonging to the first surface side region across the boundary set by the boundary setting unit belong to the second surface side region. Analyzing the discharge phenomenon between them and those belonging to the region on the second surface side across the boundary set by the boundary setting unit are those belonging to the region on the first surface side A discharge analysis unit for analyzing the discharge phenomenon between
Program to make the electronic computer function.

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