Control System

Abstract

To provide a technology related to movement control of a carriage, considering a temperature rise of a motor.SOLUTION: A control system is configured such that a carriage 41, on which a processing head 22 is mounted, is driven by a motor 51 and reciprocates. The motor is controlled by a controller 11. The controller selects one of multiple control modes as a target mode, based on temperature information related to a temperature of the motor, and causes the carriage to reciprocate by controlling the motor in the target mode. The controller, for each particular work unit, selects the target mode to be applied to the control of the motor for the processing of the corresponding work unit. The target mode is selected from a group of control modes among the multiple control modes. Each control mode in the group of control modes is a control mode in which a maximum temperature of the motor, in a case where the control of the motor using the selected control mode would be executed until the processing of the corresponding work unit is completed, is less than a reference value, the maximum temperature of the motor being a temperature estimated based on the temperature information.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present disclosure relates to control systems. [Background technology]

[0002] An inkjet printer is already known that estimates the temperature of a motor that drives a carriage, and temporarily halts the driving of the motor when the estimated motor temperature is equal to or higher than a threshold value (see, for example, Patent Document 1). Inkjet printers that increase the moving speed of a carriage carrying an inkjet head in non-image areas sandwiched between image areas to speed up processing are also known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-226818 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in a system in which an object is processed by moving a carriage carrying a processing head, if the carriage speed is increased in non-processing areas, the temperature of the motor that drives the carriage is more likely to rise than if this is not done.

[0005] If the motor temperature exceeds the allowable range, it becomes necessary to temporarily stop the motor. If the motor continues to be in a high temperature state without pausing, the system life will be shortened. On the other hand, if the motor is temporarily stopped while the object is being processed, it may have an undesirable effect on the processing result.

[0006] For example, in an inkjet printer, interlace control may be used to eject ink droplets in multiple separate bursts onto the same area of ​​a sheet, and the resulting droplets may then be superimposed to form an image. In such image formation involving interlace control, a pause during superposition extends the drying period of the ink previously ejected onto the sheet, resulting in a visible change in the quality of the image formed on the sheet compared to a case where there was no pause. In systems that process objects using droplets, not limited to inkjet printers, the drying time and reaction time of the droplets may affect the processing quality.

[0007] Therefore, according to one aspect of the present disclosure, it is desirable to provide a new technique for controlling carriage movement in consideration of motor temperature rise in a system that processes an object by ejecting droplets onto the object. [Means for solving the problem]

[0008] According to one aspect of the present disclosure, there is provided a control system including a motor, a carriage, a processing head, and a controller, the carriage being configured to be driven by the motor to reciprocate.

[0009] The processing head is mounted to the carriage and configured to process the object by ejecting droplets onto the object along a path of movement of the carriage. The controller is configured to control the motor.

[0010] Specifically, the controller acquires temperature information regarding the temperature of the motor, selects one of a plurality of control modes as a target mode based on the temperature information, and controls the motor in the target mode to reciprocate the carriage.

[0011] The plurality of control modes are control modes in which the target acceleration and deceleration motion of the carriage from when the carriage starts to move until when it stops at a turning point are different from one another. The selection includes selecting, for each predetermined work unit related to the machining of the object, a target mode to be applied to the control of the motor accompanying the machining of the corresponding work unit.

[0012] The target mode is selected from a group of control modes, among which a temperature is estimated based on temperature information, and in which the maximum temperature of the motor when control of the motor is hypothetically performed using the selected control mode until processing of the corresponding work unit is completed is less than a reference value.

[0013] According to this control system, the control modes in which the maximum temperature of the motor is estimated to be equal to or higher than the reference value are estimated before control, and motor control in these control modes is not executed. Therefore, it is possible to suppress the occurrence of disadvantages caused by the motor becoming too hot. For example, it is possible to suppress the shortening of the motor's life due to the motor becoming too hot, and the occurrence of undesirable effects on the processing quality of the object due to a temporary stop operation during processing.

[0014] Therefore, according to this control system, in a system for machining an object, it is possible to realize appropriate carriage movement control that takes into account the temperature rise of the motor. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a block diagram illustrating a configuration of an image forming system 1. [Diagram 2] FIG. 2A is a flowchart showing a job registration process executed by the processor, and FIG. 2B is a flowchart showing a job-related process executed by the processor. [Diagram 3] FIG. 2 is an explanatory diagram of a carriage transport mechanism and a paper transport mechanism. [Figure 4] 4 is a flowchart showing a printing process executed by a processor. [Diagram 5]FIG. 5A is a graph representing a first type of velocity profile, FIG. 5B is a graph representing a second type of velocity profile, and FIG. 5C is a graph representing a third type of velocity profile. [Figure 6] 11 is a flowchart showing a speed profile setting process executed by a processor. [Figure 7] 11 is a flowchart showing a profile type selection process executed by a processor. [Figure 8] 11 is a flowchart showing a temperature estimation process executed by a processor. [Figure 9] 11 is a flowchart showing a protection process executed by a processor. [Figure 10] 13 is a flowchart illustrating a modified example of job-related processing executed by a processor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Exemplary embodiments of the present disclosure will now be described with reference to the drawings. 1 is an inkjet printer that forms an image by ejecting ink droplets onto a sheet of paper P to be processed. The image forming system 1 includes a processor 11, a ROM 12, a RAM 13, an EEPROM 15, a user interface 17, a communication interface 19, and an ASIC 20. The ASIC 20 includes a recording control unit 21, a CR (carriage) motor control unit 31, and an LF (line feed) motor control unit 35.

[0017] The image forming system 1 further includes a recording head 22 and a drive circuit 23 as components for forming an image on the paper P. The image forming system 1 further includes a carriage transport mechanism 40, a CR motor 51, a drive circuit 53, and an encoder 55 as components for moving the recording head 22 in the main scanning direction. The carriage transport mechanism 40 includes a carriage 41 on which the recording head 22 is mounted.

[0018] The image forming system 1 further includes a paper transport mechanism 60, an LF motor 71, a drive circuit 73, and an encoder 75 as components for transporting the paper P in a sub-scanning direction perpendicular to the main scanning direction. The image forming system 1 further includes a temperature sensor 81 for measuring the temperature of the CR motor 51.

[0019] The processor 11 performs overall control of the image forming system 1 and realizes various functions by executing processes according to computer programs recorded in the ROM 12. The ROM 12 stores various computer programs. The RAM 13 is used as a working memory when the processor 11 executes processes. The EEPROM 15 is an electrically rewritable non-volatile memory, and stores various setting information.

[0020] The user interface 17 includes an operation unit that can be operated by a user and a display unit that can display various information to the user. The communication interface 19 is configured to be capable of communicating with an external device such as a personal computer.

[0021] 2A, processor 11 registers the corresponding print job in a queue (S120) every time a print command is received from an external device (Yes in S110). At this time, processor 11 temporarily stores the data to be printed received together with the print command in RAM 13. The data to be printed is data to be image-printed on paper P in a print process corresponding to the print job. The print command corresponds to a command to register and execute the print job.

[0022] In parallel with the job registration process, processor 11 repeatedly executes the job-related processes shown in FIG. 2B, and when unprocessed print jobs are registered in the queue (Yes at S150), processor 11 selects one of the unprocessed print jobs as the target for processing and executes the print processing corresponding to the selected print job (S160).

[0023] In the printing process (S160), the processor 11 causes the recording control unit 21 to control the ejection of ink droplets from the recording head 22, causes the CR motor control unit 31 to control the movement of the carriage 41 by controlling the CR motor 51, and causes the LF motor control unit 35 to control the transport of the paper P by controlling the LF motor 71. As a result, an image is formed on the paper P based on the print target data received when the corresponding print job was registered.

[0024] The recording head 22 (see FIG. 1) is a processing head for printing the paper P, and specifically, is an inkjet head in which a plurality of nozzles for ejecting ink droplets are arranged. The recording head 22 is driven by a drive circuit 23, and prints the paper P by ejecting ink droplets onto the opposing paper P along the movement path of the carriage 41.

[0025] Based on a command from the processor 11, the recording control unit 21 inputs a control signal to a drive circuit 23 and controls the ink droplet ejection operation by the recording head 22 so that an image based on the data to be printed is formed on the paper P.

[0026] 3, the carriage transport mechanism 40 includes a carriage 41 that carries the recording head 22, a guide rail 42, and a belt mechanism 43. The carriage transport mechanism 40 is configured to be driven by a CR motor 51 to reciprocate the carriage 41 in the main scanning direction.

[0027] The guide rail 42 is configured to limit the movement of the carriage 41 in the main scanning direction. The belt mechanism 43 includes a driving pulley 431, a driven pulley 433, and a belt 435 wound between the driving pulley 431 and the driven pulley 433. The carriage 41 is fixed to the belt 435.

[0028] In the belt mechanism 43, the driving pulley 431 rotates by receiving power from the CR motor 51, and the belt 435 and the driven pulley 433 rotate in accordance with the rotation of the driving pulley 431. Due to this rotation, the carriage 41 moves in the main scanning direction along the guide rail 42.

[0029] The CR motor 51 is, for example, a DC motor, and is driven by a drive circuit 53. The drive circuit 53 applies a drive voltage to the CR motor 51 in accordance with a control signal input from the CR motor control unit 31, to drive the CR motor 51.

[0030] The CR motor control unit 31 operates according to commands from the processor 11, and controls the CR motor 51 so that the carriage 41 moves in the main scanning direction at a speed that follows the speed profile specified by the processor 11. At this time, the CR motor control unit 31 feedback-controls the speed of the carriage 41 based on an encoder signal input from the encoder 55.

[0031] The encoder 55 is configured as, for example, a linear encoder. The linear encoder can include an encoder scale (not shown) provided along the guide rail 42 and an optical sensor (not shown) mounted on the carriage 41.

[0032] The encoder 55 outputs, as an encoder signal, a pulse signal corresponding to the displacement in the main scanning direction of the carriage 41. The CR motor control unit 31 measures the position and speed of the carriage 41 in the main scanning direction based on this encoder signal, and controls the movement of the carriage 41 in the main scanning direction through control of the CR motor 51.

[0033] 3, the paper transport mechanism 60 includes a roller 61 having an axis parallel to the main scanning direction and driven to rotate in the sub-scanning direction by an LF motor 71. The paper transport mechanism 60 transports paper P, which is supplied one sheet at a time from a tray, in the sub-scanning direction by the rotation of the roller 61, and supplies the paper P to a position where ink droplets are ejected by the recording head 22.

[0034] The LF motor 71 is, for example, a DC motor, and is driven by a drive circuit 73. The drive circuit 73 drives the LF motor 71 in accordance with a control signal input from the LF motor control unit .

[0035] The LF motor control unit 35 generates a control signal for the drive circuit 73 in accordance with a command from the processor 11, and controls the LF motor 71. The LF motor control unit 35 controls the transport of the paper P by feedback control based on an output signal from an encoder 75 serving as a rotary encoder provided in the LF motor 71, the roller 61, or a transmission system between them.

[0036] Next, details of the print process executed by the processor 11 in S160 will be described with reference to Fig. 4. In the print process, an image based on the print target data received when the print job was registered is formed on paper P. If the print target data includes page image data for multiple pages, a page image based on the corresponding page image data for each page is formed on one sheet of paper P corresponding to one page.

[0037] When the processor 11 starts the print process, it executes the profile type selection process of S210 for each page, and then executes the page print process (S220-S280) which is the image formation process for the page.

[0038] 7 (described in detail later) to select a target profile type, which is a type of speed profile used for controlling the speed of the carriage 41 in the page printing process (S220-S280). In S210, the processor 11 refers to the page image data to be processed that corresponds to the page image to be formed on the paper P, and selects the target profile type.

[0039] 5A-5C, the processor 11 selects, as the target profile type, the type of speed profile that provides the shortest movement time of the carriage 41 within a range in which the CR motor 51 does not reach or exceed the protection temperature, taking into consideration the temperature rise of the CR motor 51. The protection temperature is determined in advance as the temperature at which the CR motor 51 needs to be protected from damage due to high temperatures by stopping driving.

[0040] When a page image is formed on paper P, the carriage 41 reciprocates through control of the CR motor 51 by the CR motor control unit 31. When the carriage 41 moves from one turning point to another, the CR motor 51 is controlled so that the carriage 41 moves at a speed that follows the speed profile.

[0041] The speed profile defines the target speed Vr at each time point while the carriage 41 moves from a movement start point corresponding to a turn-around point to a target stop point corresponding to the next turn-around point. An ink ejection section in which ink droplets are ejected from the recording head 22 is included between the movement start point and the target stop point.

[0042] For the ink ejection section, a first speed Vr1 that is predetermined for forming an image of good quality on the paper P is set as the target speed Vr, and the CR motor 51 is controlled so that the carriage 41 moves at a constant speed of the first speed Vr1.

[0043] 5A-5C are defined so that the target speed Vr in the non-ink ejection section is different. Specifically, the three types include a speed profile type in which the target speed Vr in the non-ink ejection section is a first speed Vr1, a speed profile type in which the target speed Vr in the non-ink ejection section is a second speed Vr2 that is higher than the first speed Vr1, and a speed profile type in which the target speed Vr in the non-ink ejection section is a third speed Vr3 that is higher than the second speed Vr2.

[0044] The first type of velocity profile shown in FIG. 5A specifically has the following characteristics. The acceleration section includes an acceleration section in which the carriage 41 is accelerated from the movement start point to the first velocity Vr1. The end point of the acceleration section is before the start point of the ink ejection section. The period from when the carriage 41 finishes accelerating to the first velocity Vr1 until when the carriage 41 reaches the end point of the ink ejection period includes a constant velocity period in which the carriage 41 moves at a constant speed of the first velocity Vr1. The re-acceleration section includes a re-acceleration section in which the carriage 41 is accelerated to the third velocity Vr3 immediately after the carriage 41 passes the end point of the ink ejection section. From the point at which the carriage 41 finishes accelerating to the third speed Vr3 until the carriage 41 reaches the deceleration start point a distance before the target stopping point required for deceleration, a high-speed section is included in which the carriage 41 moves at a constant speed at the third speed Vr3. The deceleration section includes a deceleration section in which the carriage 41 decelerates and stops toward the target stopping point immediately after the carriage 41 reaches the deceleration start point.

[0045] 5B has the same shape as the first type of speed profile, but has a second speed Vr2 lower than the third speed Vr3 instead of the third speed Vr3. That is, the second type of speed profile is a type of speed profile in which the target speed Vr in the high speed section is the second speed Vr2 lower than the third speed Vr3.

[0046] The third type of velocity profile shown in FIG. 5C has the following characteristics: The acceleration section includes an acceleration section in which the carriage 41 is accelerated from the movement start point to the first velocity Vr1. The end point of the acceleration section is before the start point of the ink ejection section. The period from when the acceleration of the carriage 41 to the first speed Vr1 ends until the carriage 41 passes through the ink ejection section and reaches the deceleration start point that is the distance before the target stopping point that is required for deceleration, includes a constant speed section in which the carriage 41 moves at a constant speed at the first speed Vr1. The deceleration section includes a deceleration section in which the carriage 41 decelerates and stops toward the target stopping point immediately after the carriage 41 reaches the deceleration start point.

[0047] In this way, the three types of speed profiles differ from one another in the target speed Vr and its change in the non-ink ejection section in the intermediate section between the acceleration section and the deceleration section. After selecting the target profile type in S210, the processor 11 starts the paper feed process in the following S220.

[0048] In the paper feed process, the processor 11 causes the LF motor control unit 35 to control the LF motor 71 so that a sheet of paper P is separated from a paper feed tray (not shown) and transported in the sub-scanning direction to a position where ink droplets are ejected by the recording head 22. The processor 11 further causes the CR motor control unit 31 to control the CR motor 51, so that the carriage 41, which is located at the home position, is placed at the initial position (S230).

[0049] Thereafter, the processor 11 sets, in the CR motor control unit 31, a speed profile that defines a target speed Vr from the movement start point to the target stopping point of the carriage 41 (S240). The speed profile that is set is a speed profile of the target profile type selected in the profile selection process.

[0050] In S240, the processor 11 executes the speed profile setting process shown in Fig. 6, and can set a speed profile according to the ink ejection section. When the speed profile setting process starts, the processor 11 determines (S310) an ink ejection section in which the ink droplet ejection operation by the recording head 22 is performed, within the movement path from the movement start point of the carriage 41 to the target stopping point in the next main scanning direction printing (S250).

[0051] The processor 11 further determines whether the target profile type selected in the profile selection process is the first type (S320). If the target profile type is the first type (Yes in S320), the processor 11 executes the process of S330.

[0052] In S330, the processor 11 generates a speed profile that defines the target speed Vr so that the carriage 41 accelerates from the start point of movement so that the carriage 41 reaches the first speed Vr1 before the ink ejection section, and after the acceleration ends, the carriage 41 moves at a constant speed at the first speed Vr1 until it reaches the end point of the ink ejection section, and then the carriage 41 accelerates again to a third speed Vr3, moves at a constant speed at the third speed Vr3 until the deceleration start point, and then decelerates and stops from the deceleration start point toward the target stopping point, and sets the generated speed profile in the CR motor control unit 31.

[0053] When the processor 11 determines that the target profile type selected in the profile selection process is not the first type (No in S320) but is the second type (Yes in S340), the processor 11 executes the process of S350.

[0054] In S350, the processor 11 generates a speed profile that defines the target speed Vr so that the carriage 41 accelerates from the start point of movement so that the carriage 41 reaches a first speed Vr1 before the ink ejection section, and after the acceleration ends, the carriage 41 moves at a constant speed at the first speed Vr1 until it reaches the end point of the ink ejection section, and then the carriage 41 accelerates again to a second speed Vr2 lower than the third speed Vr3, moves at a constant speed at the second speed Vr2 until the deceleration start point, and then decelerates and stops from the deceleration start point toward the target stop point, and sets the generated speed profile in the CR motor control unit 31.

[0055] When the processor 11 determines that the target profile type selected in the profile selection process is not the second type but the third type (No in S340), the processor 11 executes the process of S360.

[0056] In S360, the processor 11 generates a speed profile that defines a target speed Vr so that the carriage 41 accelerates from the start point of movement so that the carriage 41 reaches a first speed Vr1 before the ink ejection section, and after the acceleration ends, the carriage 41 moves at a constant speed at the first speed Vr1 until it passes the end point of the ink ejection section and reaches the deceleration start point, and then decelerates and stops from the deceleration start point toward the target stopping point, and sets the generated speed profile in the CR motor control unit 31.

[0057] After setting the speed profile in S240, the processor 11 executes printing in the main scanning direction (S250). In S250, the processor 11 commands the CR motor control unit 31 to execute control of the CR motor 51 in accordance with the speed profile set in S240.

[0058] The processor 11 further inputs image data representing one pass's worth of image to be formed on the paper P to the recording control unit 21, and instructs the recording control unit 21 to control the ink droplet ejection operation by the recording head 22 based on this image data. The one pass's worth of image to be formed on the paper P is the image to be formed on the paper P by the ink droplet ejection operation in the process in which the carriage 41 moves in the main scanning direction from one turning point to another.

[0059] In response to this command, the CR motor control unit 31 controls the CR motor 51 so that the carriage 41 moves from the movement start point to the next turning point corresponding to the target stopping point along a speed trajectory that follows the set speed profile.

[0060] Specifically, based on the speed profile, the CR motor control unit 31 feedback controls the speed of the carriage 41. For example, the CR motor control unit 31 calculates the deviation E=Vr-V between the target speed Vr according to the speed profile and the speed V of the carriage 41 measured based on the encoder signal.

[0061] The CR motor control unit 31 inputs the deviation E into a predetermined transfer function to calculate a voltage command value corresponding to the drive voltage to be applied to the CR motor 51 as an operation amount U for the CR motor 51, and inputs a corresponding control signal to the drive circuit 53.

[0062] The recording control unit 21 controls the recording head 22 so that the recording head 22 ejects ink droplets for forming an image corresponding to the image data in accordance with the movement of the carriage 41. By executing the main scanning direction printing in S250, an image for one pass based on the image data is formed on the paper P.

[0063] When the main scanning direction printing in S250 is completed, the processor 11 judges whether the printing process for one page of the paper P is completed (S260). If it is determined that the printing process is not completed (No in S260), the processor 11 causes the LF motor control unit 35 to control the LF motor 71 so as to transport the paper P in the sub-scanning direction by a predetermined distance corresponding to the width of the image for one pass in the sub-scanning direction (S270).

[0064] After executing the process of S270, the processor 11 sets the speed profile to be used in the next main scanning direction printing (S240). Since the profile type selection process (S210) is executed for each page, the same type of speed profile is set for the same page.

[0065] After setting the speed profile, processor 11 executes main scanning direction printing (S250) to form an image for one pass on paper P that has been sent a predetermined distance in the sub scanning direction in the immediately preceding process of S270.

[0066] Processor 11 repeatedly executes the processes of S240-S270 until it determines that printing of one page of paper P is complete, and when it determines that printing of one page of paper P is complete (Yes in S260), it executes the process of S280.

[0067] In S280, the processor 11 executes a paper discharge process for the printed paper P. In the paper discharge process, the LF motor 71 is controlled via the ASIC 20 to discharge the printed paper P onto a paper discharge tray (not shown).

[0068] Processor 11 further determines whether the print job being processed has page image data for the next page (S290), and if it determines that the print job has page image data for the next page (Yes at S290), it returns to S210 and executes profile selection processing (S210) and page printing processing (S220-S280) for the next page.

[0069] In this way, the processor 11 sets a target profile type for each page, and when printing the same page in the main scanning direction, controls the movement of the carriage 41 based on the same type of speed profile to form an image on the paper P. Then, when the page printing process for all pages is completed (No in S290), the printing process ends.

[0070] Next, details of the profile type selection process executed by the processor 11 in S210 will be described with reference to Fig. 7. When the profile type selection process starts, the processor 11 estimates the maximum temperature Tx of the CR motor 51 when a page print process is hypothetically executed to form a page image based on the page image data to be processed on paper P using the first type of speed profile (Fig. 5A) (S410).

[0071] Thereafter, the processor 11 determines (S420) whether the estimated maximum temperature Tx is less than a predetermined protection temperature of the CR motor 51. When the processor 11 determines that the estimated maximum temperature Tx is less than the protection temperature (Yes in S420), it selects the first type of speed profile as the target profile type (S430).

[0072] On the other hand, if the processor 11 makes a negative judgment in S420, it estimates the maximum temperature Tx of the CR motor 51 when a page printing process is hypothetically performed to form a page image based on the page image data to be processed on paper P using the second type of speed profile (Figure 5B) (S440).

[0073] Then, the processor 11 determines whether the estimated maximum temperature Tx is less than the protection temperature (S450). If the processor 11 determines that the estimated maximum temperature Tx is less than the protection temperature (Yes in S450), it selects the second type of speed profile as the target profile type (S460).

[0074] In addition, if the processor 11 makes a negative decision in S450, it selects the third type of speed profile as the target profile type (S470), and then ends the profile selection process.

[0075] When estimating the maximum temperature Tx in S410 and S440, the processor 11 executes the temperature estimation process shown in Fig. 8 to estimate the maximum temperature Tx when the CR motor 51 is hypothetically driven using the corresponding target profile type. The corresponding target profile type is the first type (see Fig. 5A) when estimating the maximum temperature Tx in S410, and is the second type (see Fig. 5B) when estimating the maximum temperature Tx in S440.

[0076] When the temperature estimation process starts, the processor 11 determines the current temperature T0 of the CR motor 51 based on the temperature information acquired from the temperature sensor 81 via the ASIC 20 (S510).

[0077] If the temperature sensor 81 is located away from the CR motor 51, there may be a discrepancy between the temperature detected by the temperature sensor 81 and the temperature of the CR motor 51. In this case, the processor 11 can determine the current temperature T0 of the CR motor 51 by calculation based on the temperature information acquired from the temperature sensor 81.

[0078] Alternatively, the processor 11 can determine the current temperature T0 of the CR motor 51 without using the temperature sensor 81, by physical calculations based on the amount of heat generated and the amount of heat dissipated by the CR motor 51, under the assumption that the CR motor 51 will drop to room temperature and stabilize when in the idle state.

[0079] After determining the current temperature T0, the processor 11 initializes the count value n to the value 1. Then, the processor 11 calculates a first scanning amount D1, which is the scanning amount of the first section, and a second scanning amount D2, which is the scanning amount of the second section, during the execution of the nth main scanning direction printing when the page printing process is executed using the speed profile of the corresponding target profile type (S540). The first scanning amount D1 and the second scanning amount D2 are the moving distance of the carriage 41 or the driving time of the CR motor 51 in the first section and the second section, respectively.

[0080] The first section here is the section from the start point of the movement of the carriage 41, i.e., the beginning of the acceleration section, through the constant speed section to reach the midpoint of the re-acceleration section, and the second section is the section from the midpoint of the re-acceleration section, through the remaining section of the re-acceleration section, the high speed section, and the deceleration section, until the carriage 41 stops at the target stopping point.

[0081] In S540, a provisional velocity profile is generated in a manner similar to the velocity profile setting process shown in FIG. 6, and a first scanning amount D1 and a second scanning amount D2 when the movement of the carriage 41 is controlled according to the velocity profile are calculated.

[0082] Then, the processor 11 uses the temperature estimation function f(Tp, D1, D2) of the corresponding profile type to calculate the estimated temperature T=f(Tp, D1, D2) of the CR motor 51 at the end of the nth main scanning direction printing when the nth main scanning direction printing is performed (S550).

[0083] The temperature estimation function f(Tp, D1, D2) includes as input variables the first scanning amount D1 and the second scanning amount D2 in the nth main scanning direction printing, and the estimated temperature Tp of the CR motor 51 at the end of the n-1th main scanning direction printing. When n=1, the estimated temperature Tp of the CR motor 51 at the end of the n-1th main scanning direction printing is the current temperature T0 determined in S510.

[0084] In a simple example, the temperature estimation function f(Tp, D1, D2) is expressed by the formula f(Tp, D1, D2)=Tp+K1+K2*(D2 / D1). The values ​​K1 and K2 are predetermined fixed values, and the value K2 varies depending on the type of speed profile. However, the value K1 may be a value proportional to the scanning amount (D1+D2) from turning point to turning point. The value K1 is the temperature rise amount of the CR motor 51 when the carriage 41 is moved from turning point to turning point without a high-speed section according to the third type of speed profile, and the value K2 is an increase coefficient of the temperature rise amount associated with the high-speed movement of the carriage 41.

[0085] According to another example, the temperature estimation function f(Tp, D1, D2) is expressed by the formula f(Tp, D1, D2) = Tp + K1 + K2 * {(V2 * D2) / (V1 * D1)}. Here, the first scanning amount D1 is the moving distance of the carriage 41 in the first section, and the second scanning amount D2 is the moving distance of the carriage 41 in the second section. V1 is the average moving speed of the carriage 41 in the first section, and V2 is the average moving speed of the carriage 41 in the second section. In other words, {(V2 * D2) / (V1 * D1)} corresponds to the ratio of the product of the speed and the moving distance in each section.

[0086] As yet another example, in S550, the estimated temperature T of the CR motor 51 at the end of the nth main scanning direction printing may be calculated according to a temperature estimation equation expressed by the following equation (1), which includes the movement distance S1 of the carriage 41 in the first section as the first scanning amount D1 and the drive time t1 of the CR motor 51, and the movement distance S2 of the carriage 41 in the second section as the second scanning amount D2 and the drive time t2 of the CR motor 51.

[0087]

number

[0088] In the above formula (1), t is the elapsed time from the end of the (n-1)th main scanning direction printing, C is the specific heat, and k is the thermal conductivity. For i=1 or 2, Ei is the average drive voltage of the CR motor 51 in the i-th section, Vi is the average speed of the carriage 41 in the i-th section, and Fi is the sliding resistance in the i-th section. In addition, Te is the environmental temperature, R is the motor resistance, and a is the torque multiplier. The environmental temperature Te can be determined based on an input from a thermistor (not shown) that measures the ink temperature.

[0089] Equation (1) includes a temperature decrease term due to heat dissipation after the CR motor 51 stops driving, a temperature increase term due to heat generated by driving the CR motor 51, and a temperature decrease term due to heat loss due to sliding resistance.

[0090] Thereafter, the processor 11 estimates the maximum value of the estimated temperatures T at the end of the first to nth main scanning direction printing as the maximum temperature Tx of the CR motor 51 during page printing processing according to the corresponding target profile type (S560).

[0091] After completing the process in S560, the processor 11 determines whether or not the temperature estimation for the entire page is completed (S570), that is, whether or not the processes in S540-S560 for the entire page are completed.

[0092] If it is determined that temperature estimation for the entire page is not complete (No in S570), the processor 11 increments the count value n by 1 (S580), calculates the estimated temperature T at the end of the next main scanning direction printing (S540, S550), and further estimates the maximum temperature Tx (S560).

[0093] When it is determined that the temperature estimation for the entire page is completed (Yes in S570), the temperature estimation process ends. The processor 11 uses this temperature estimation process to estimate the maximum temperature Tx of the CR motor 51 until the page print process is completed when the page print process is executed for the entire page using the corresponding target profile type.

[0094] 9 while the CR motor 51 is being driven. In the protection process, the processor 11 determines whether the current temperature of the CR motor 51 is equal to or higher than a protection temperature (S610). The processor 11 can determine the temperature of the CR motor 51 based on temperature information from the temperature sensor 81 acquired via the ASIC 20.

[0095] When it is determined that the temperature of the CR motor 51 is equal to or higher than the protection temperature (Yes in S610), the processor 11 commands the CR motor control unit 31 to temporarily stop the CR motor 51 (S620).

[0096] After issuing the command to temporarily stop the CR motor 51, the processor 11 waits until the temperature of the CR motor 51 drops below a protection release temperature that is a temperature lower than the protection temperature and is determined in advance (S630). When the processor 11 determines that the temperature of the CR motor 51 has dropped below the protection release temperature (Yes in S630), it commands the CR motor control unit 31 to resume driving the temporarily stopped CR motor 51 (S640).

[0097] According to the image forming system 1 of the present embodiment described above, the processor 11 acquires temperature information regarding the temperature of the CR motor 51 (S510), and based on this temperature information, selects one of a plurality of speed profile types that define a control mode regarding speed as a target profile type (S430, S460, S470), and controls the CR motor 51 with a speed profile that conforms to the target profile type, thereby causing the carriage 41 to reciprocate.

[0098] The above-mentioned multiple speed profile types are types of speed profiles that have different target acceleration / deceleration motion of the carriage from when the carriage 41 starts moving until it stops at the turning point, particularly target speeds in the non-ink ejection section. Due to the difference in target speed, the movement time of the carriage 41 from the movement start point to the turning point and the amount of heat generated by the CR motor 51 differ between the multiple speed profile types.

[0099] For each page printed in one print job, the processor 11 determines the current temperature T0 of the CR motor 51 prior to the start of the corresponding page printing process, and based on that, estimates the maximum temperature Tx of the CR motor 51 when the page printing process is hypothetically performed with each type of speed profile (S210).

[0100] Then, the processor 11 selects, from a group of speed profile types in which the maximum temperature Tx of the CR motor 51 is less than the protection temperature, the speed profile type that has the shortest movement time of the carriage 41 and the best throughput for page printing as the target profile type to be applied to the page printing process (S210).

[0101] This enables the processor 11 to execute the page printing process using the speed profile with the best throughput within the range in which it is estimated that the CR motor 51 will not reach or exceed the protection temperature during printing of one page of paper P and be temporarily stopped.

[0102] Therefore, according to this embodiment, when printing a page image, the drive of the CR motor 51 is temporarily stopped by the protection process, which temporarily stops the drive of the carriage 41 and the ejection of ink droplets, thereby changing the drying time of the ink droplets at each location on the paper P and preventing unevenness in image quality within one page. As a result, according to this embodiment, it is possible to provide an image forming system 1 with high image quality and good throughput.

[0103] In particular, when interlace control involves ejecting ink droplets in multiple batches onto the same area of ​​paper P and forming an image by overlapping the droplets, a pause during the overlapping process extends the drying period of the ink that was previously ejected onto the paper P, resulting in a visible change in the quality of the image formed on the paper P compared to when there was no pause. However, according to this embodiment, the occurrence of uneven image quality due to such pauses can be suppressed.

[0104] The present disclosure is not limited to the above embodiment, and may be modified in various ways. For example, the profile type selection process shown in FIG. 7 may be performed on a processing basis other than a page basis, specifically, on a print job basis.

[0105] That is, processor 11 may be configured not to execute the profile type selection process (S210) for each page in the printing process (see FIG. 4). Processor 11 may be configured to execute the profile type selection process for each print job before execution of the corresponding printing process by repeatedly executing the job-related process shown in FIG. 10 instead of the job-related process shown in FIG. 2B.

[0106] According to the job-related processing of the modified example shown in FIG. 10, when unprocessed print jobs are registered in the queue (Yes in S810), processor 11 selects one of the unprocessed print jobs as the target for processing and executes print processing corresponding to the selected print job (S830), but prior to the print processing, it executes a profile type selection process (S820).

[0107] In the profile type selection process in S820, the processor 11 estimates the maximum temperature Tx of the CR motor 51 when a print process corresponding to the print job being processed is executed using the first type of speed profile (see FIG. 5A) (S410), as will be described in parentheses in FIG. 7, and selects the first type of speed profile as the target profile type (S430) when the estimated temperature Tx is below the protection temperature (Yes in S420). The target profile type here is the type of speed profile used for controlling the speed of the carriage 41 in the print process (S220-S290) for the entire print job being processed.

[0108] If the judgment in S420 is negative, the processor 11 uses the second type of speed profile (see FIG. 5B) to estimate the maximum temperature Tx of the CR motor 51 when executing the printing process corresponding to the print job to be processed (S440), and if the estimated maximum temperature Tx is less than the protection temperature (Yes in S450), selects the second type of speed profile as the target profile type (S460).

[0109] If the processor 11 makes a negative determination in S420 and S450, it selects the third type of speed profile as the target profile type for the entire print job to be processed (S470).

[0110] According to this modification, a target profile type is selected for each print job based on the maximum temperature Tx of the CR motor 51 in the corresponding print job, so that it is possible to prevent the CR motor 51 from reaching or exceeding the protection temperature between the start and end of a print job, causing the CR motor 51 to temporarily stop. This makes it possible to prevent unevenness in image quality from occurring throughout a document spanning multiple pages that is printed in a print job. This makes it possible to provide an image forming system 1 that provides high image quality and good throughput.

[0111] As yet another variant, the processor 11 may operate to estimate the maximum temperature of the CR motor 51 until the end of the corresponding main scanning direction printing prior to each pass, i.e., each time main scanning direction printing is executed, and to select as the target profile type the type having the shortest travel time to the target stopping point among the types of speed profiles in which the estimated maximum temperature is less than the protection temperature.

[0112] Alternatively, in the profile type selection process, a reference temperature set to a temperature lower than the protection temperature may be used instead of the protection temperature, and a target profile type may be selected based on a comparison between the estimated maximum temperature Tx and the reference temperature. By selecting the target profile type based on this reference temperature, it is possible to further reduce the possibility that the CR motor 51 will reach or exceed the protection temperature and pause.

[0113] The technology disclosed herein is applicable not only to inkjet printers but also to control systems of other serial printers, garment printers, etc. The technology disclosed herein is also applicable to control systems of industrial machines that eject a chemical onto an object and process the object by a reaction between the object and the chemical.

[0114] The functions of one component in the above embodiment may be distributed among multiple components. The functions of multiple components may be integrated into one component. The controller may not be configured with the processor 11 and the ASIC 20, but may be configured with one or more processors without an ASIC, may be configured with one or more ASICs without a processor, or may be configured with a combination of one or more processors and one or more ASICs. One or more components of the controller including at least one of a processor and an ASIC can cooperate with each other to execute the processing related to the controller of the present disclosure.

[0115] In addition, some of the configurations of the embodiments may be omitted. All aspects included in the technical ideas specified by the wording of the claims are embodiments of the present disclosure. [Explanation of symbols]

[0116] 1...image forming system, 20...ASIC, 11...processor, 12...ROM, 13...RAM, 15...EEPROM, 17...user interface, 19...communication interface, 21...recording control unit, 22...recording head, 23...drive circuit, 31...CR motor control unit, 35...LF motor control unit, 40...carriage transport mechanism, 41...carriage, 42...guide rail, 43...belt mechanism, 51...CR motor, 53...drive circuit, 55...encoder, 60...paper transport mechanism, 61...roller, 71...LF motor, 73...drive circuit, 75...encoder, 81...temperature sensor.

Claims

1. A motor; a carriage configured to be driven by the motor and to move back and forth; a processing head mounted on the carriage and configured to process an object by discharging droplets onto the object along a path of movement of the carriage; a controller configured to control the motor; Equipped with The controller: obtaining temperature information relating to a temperature of the motor; selecting one of a plurality of control modes as a target mode based on the temperature information; Each time a job execution command is input, the following is executed as the job: reciprocating the carriage by controlling the motor in the target mode; Controlling the processing head so that a specified processing operation is applied to the object; Run the plurality of control modes are control modes in which target acceleration / deceleration motions of the carriage from when the carriage starts to move until when the carriage stops at a turning point are different from one another; the selecting includes selecting, for each execution of the job, the target mode to be applied to control of the motor in the corresponding job; The target mode is a control system selected from a group of control modes among the plurality of control modes, in which the temperature is estimated based on the temperature information, and the maximum temperature of the motor when control of the motor is hypothetically performed using the selected control mode until the corresponding job is completed is less than a reference value.

2. the processing includes forming an image on the object; The job includes, for each of a plurality of sheets as the object that are supplied one by one to the movement path, reciprocating the carriage by controlling the motor in the target mode; controlling said processing heads so that a designated image is formed on a corresponding sheet; Including, The control system according to claim 1 , wherein the target mode is selected for each execution of the job involving image formation on the plurality of sheets.

3. A motor, a carriage configured to be driven by the motor and to move back and forth; a processing head mounted on the carriage and configured to process an object by discharging droplets onto the object along a path of movement of the carriage; a controller configured to control the motor; Equipped with The processing includes forming a corresponding image on each of a plurality of sheets as the object that are fed one by one to the moving path, and The controller: obtaining temperature information relating to a temperature of the motor; selecting one of a plurality of control modes as a target mode based on the temperature information; and for each sheet fed to the moving path, reciprocating the carriage by controlling the motor in the target mode; controlling the processing head so that the corresponding image is formed on the one sheet; Perform an image forming process including the plurality of control modes are control modes in which target acceleration / deceleration motions of the carriage from when the carriage starts to move until when the carriage stops at a turning point are different from one another; the selecting includes selecting the target mode to be applied to the control of the motor in the corresponding image forming process for each execution of the image forming process on the sheet; The target mode is a control system selected from a group of control modes among the plurality of control modes, in which the temperature is estimated based on the temperature information, and the maximum temperature of the motor when control of the motor is hypothetically performed using the selected control mode until the corresponding image formation process is completed is less than a reference value.

4. The control system according to any one of claims 1 to 3, wherein the controller acquires the temperature information prior to each selection of the target mode, estimates a maximum temperature of the motor based on the acquired temperature information, and discriminates the control mode group based on the estimated maximum temperature of the motor.

5. A control system according to any one of claims 1 to 4, wherein the controller selects as the target mode a control mode from the group of control modes which has the shortest carriage movement time from when the carriage starts to move until when it stops at the turning point.

6. 6. The control system according to claim 1, wherein the plurality of control modes include two or more control modes that control the velocity of the carriage using velocity profiles of different types.

7. A motor, a carriage configured to be driven by the motor and to move back and forth; a processing head mounted on the carriage and configured to process an object by discharging droplets onto the object along a path of movement of the carriage; a controller configured to control the motor; Equipped with The controller: obtaining temperature information relating to a temperature of the motor; selecting one of a plurality of control modes as a target mode based on the temperature information; reciprocating the carriage by controlling the motor in the target mode; Run The selecting step includes selecting, for each predetermined work unit related to the processing of the object, the object mode to be applied to the control of the motor associated with the processing of the corresponding work unit; The target mode is selected from a group of control modes in which the temperature is estimated based on the temperature information, and the maximum temperature of the motor when the motor is hypothetically controlled using the selected control mode until the processing of the corresponding task unit is completed is less than a reference value; the plurality of control modes include two or more control modes in which target acceleration / deceleration motions of the carriage from when the carriage starts moving until when the carriage stops at a turning point are different from each other, and which control the speed of the carriage using speed profiles of different types from each other; a speed profile corresponding to each of the two or more control modes defines a target speed of the carriage in an acceleration section in which the carriage accelerates from a movement start point to a constant speed state, a deceleration section in which the carriage decelerates from the constant speed state to stop at a target stop point corresponding to the turning point, and an intermediate section between the acceleration section and the deceleration section; A control system wherein a target velocity of the carriage in the intermediate section differs between the two or more control modes.

8. The two or more control modes include: a first control mode for controlling the motor according to a first velocity profile defining a target velocity of the carriage such that the carriage moves at a constant first velocity in the intermediate section; a second control mode for controlling the motor in accordance with a second velocity profile defining a target velocity of the carriage such that the carriage moves at a constant velocity of the first velocity in a first section of the intermediate section, and moves at a constant velocity of a second velocity higher than the first velocity in a second section of the intermediate section; 8. The control system of claim 7, comprising:

9. The two or more control modes include: a third control mode in which the motor is controlled according to a third velocity profile that defines a target velocity of the carriage such that, in the first section, the carriage moves at a constant velocity at the first velocity, and, in the second section, the carriage moves at a constant velocity at a third velocity that is higher than the second velocity; The control system of claim 8 further comprising:

10. 10. The control system according to claim 8, wherein the first section is a section in which processing is performed on the object, and the second section is a section in which processing is not performed on the object.

11. the controller controls the motor to temporarily halt the motor when the temperature of the motor is equal to or greater than a protection temperature; The control system according to any one of claims 1 to 10, wherein the reference value is defined as a temperature equal to or lower than the protection temperature.

Images