JP4517802B2 - Pump control mechanism, printer using the pump control mechanism, and pump control method - Google Patents

Description

  The present invention relates to a pump control mechanism, a printer using the pump control mechanism, and a pump control method.

  Many popular printers are equipped with a cartridge for storing ink in a carriage. However, high-performance type printers include a type in which a cartridge is mounted on the housing side of the printer without mounting the cartridge on the carriage. This type of printer can suppress variations in the weight of the carriage even if the remaining amount of ink changes. Therefore, this type of printer can control the carriage with high accuracy.

  Here, in the above type of printer, a liquid container is mounted on the carriage. A cartridge is connected to the liquid container via a liquid conduit so that ink can be supplied from the cartridge toward the liquid container. The cartridge is connected to one end of an air pipe. The other end of the air pipe is connected to a bellows pump in the pump unit. When the bellows pump is driven, air is sent to the cartridge through the air pipe. The ink can be supplied from the cartridge into the liquid container via the liquid conduit by air pressure.

  In addition, there exists what is disclosed by patent document 1 as what utilizes such an air pressure. In the configuration disclosed in Patent Document 1, a reciprocating unit that reciprocates and compresses air, a pump motor that reciprocates the reciprocating unit, and a pressure of the liquid container with respect to the pump motor is predetermined. A power input unit that supplies power until pressure is reached.

Japanese translation of PCT publication No. 2002-510252 (see page 8, Fig. 1)

  By the way, when the bellows pump is driven by a pump motor, noise generated from noise sources such as a pump motor and a conversion mechanism becomes a problem. Among the operating sounds generated from the printer, such noise is particularly loud, and its reduction is a problem.

  In particular, when the bellows pump is expanded or contracted, the external load acting on the pump motor changes due to a change in the internal pressure of the bellows pump, and the rotation speed of the pump motor varies according to the change. For this reason, the noise generated from the noise source also fluctuates according to the fluctuation of the rotational speed. As a result, there is a problem that it is easy to hear compared to a case where a certain level of sound is constantly generated from the noise source. That is, when noise of the same level is generated, noise whose magnitude varies is felt louder than noise that is constantly generated.

  Here, when controlling the above-described pump motor, for example, if a sensor capable of detecting the rotational speed, such as a rotary encoder, is installed and the rotational speed of the pump motor is controlled using the feedback signal from the sensor, the noise Can be reduced. However, when a rotary encoder or the like is mounted, there are problems such as an increase in cost.

  The present invention has been made on the basis of the above circumstances, and an object of the present invention is to provide a pump control mechanism capable of reducing noise when the pump unit is driven, a printer using the pump control mechanism, and a pump control method. To try to provide.

  In order to solve the above-described problems, the present invention includes a pump member that applies air pressure by reciprocation, a drive source that reciprocates the pump member and that is controlled and driven based on control information, and driving the drive source. The pump member is reciprocated by the pump unit to feed the liquid stored in the liquid supply source toward the storage means, the position detection means for detecting the position of the pump member in the reciprocating motion, and the drive source is driven. In this case, the information storage means for storing the target information corresponding to the target drive speed and the drive speed of the drive source reciprocating the pump member based on the position detection of the pump member by the position detection means. The drive information calculation means for calculating the corresponding drive information is compared with the drive information and the target information, and the drive source is driven next based on these comparisons. Correction information calculating means for calculating correction information for the control information for reducing the difference between the drive information and the target information at the time of correction, and correction means for correcting the control information input to the drive source with the correction information. It has.

  When configured in this manner, the drive information calculation means calculates drive information corresponding to the drive speed of the drive source based on detection of the reciprocation of the pump member in the position detection means. Then, the correction information calculation means compares the calculated drive information with the target information, calculates correction information for reducing the difference from the target information, and the correction means uses the calculated correction information, Correct the control information. Based on the corrected control information, the drive source is controlled and driven. Thereby, the drive speed of the drive source approaches the target drive speed, and the speed of reciprocation of the pump member is also adjusted. For this reason, it is possible to suppress noise generated from the load portion such as the pump member and other friction portions. In other words, if the target information is set so that the noise generated from the load part deviates from the audible area, the generation of noise is reduced based on detection by the position detection means as the drive source is driven. Is possible.

  In addition, the generation of noise can be suppressed only by detection by the position detection means. This eliminates the need for an encoder or the like for detecting the drive speed of the drive source, and can suppress an increase in cost.

  In another invention, in addition to the above-described invention, the control information is a duty ratio for performing PWM control at the pulse voltage applied to the drive source, and the correction information is the pulse voltage in the PWM control. The duty ratio is changed. When configured in this manner, the drive speed of the drive source can be adjusted by PWM control that adjusts the duty ratio of the pulse voltage, and the drive source can be accurately controlled while being simple.

  Further, according to another invention, in addition to the above-described inventions, the position detecting means detects the position of the pump member in the reciprocating motion on the extended end side of the pump member. In such a configuration, when the position of the pump member is once detected by the position detecting means and the position of the pump member is detected again, the start and end of one cycle of the pump member can be detected. And the time of 1 cycle of a pump member can be correctly measured by measuring the time in the meantime.

  In addition to the above-described inventions, the other invention further includes drive control means for stopping / starting driving of the drive source, and the drive control means is based on the measurement of the air pressure in the pressure sensor. The drive source is stopped / started.

  In such a configuration, when it is detected by the pressure sensor that the prescribed pressure has been reached, the drive control means stops the drive source. Therefore, it is possible to prevent the liquid from overflowing from the storage unit due to the pump member exerting excessive pressure on the storage unit such as the liquid container. That is, an appropriate amount of liquid can be supplied from the liquid supply source to the storage means, and the storage means can be in a state where an appropriate amount of liquid is stored. Further, when the specified pressure is not reached, the drive control means starts driving the drive source. Thereby, the storage means can always store a prescribed amount of liquid.

  Furthermore, in another invention, in addition to the above-described inventions, the drive control means stops driving of the drive means on the extended end side. In this case, when the drive source is driven next time and the position of the pump member is detected by the position detection means, the time until the detection becomes the first cycle. That is, at the initial position detection stage, accurate cycle measurement can be performed, and calming can be achieved more quickly.

  In another invention, in addition to the above-described inventions, the correction information is added from the third cycle of the reciprocation of the pump member. When configured in this way, the third period is corrected with correction information based on the accurate period measured in the second period. For this reason, even when the pump member is stopped in the middle of the reciprocating motion, the accurate cycle can be measured in the second cycle. Therefore, the accurate correction information calculated from the second cycle is used in the third cycle. Can be projected.

  In another invention, in addition to the above-described inventions, the drive information calculation means further includes timer means for measuring the time until the position detection means detects, and the time measurement by the timer means is specified. If the position detection means does not detect the position of the pump member in the reciprocating motion even if the time limit is exceeded, the correction means corrects the control information with correction information that increases the duty ratio.

  In this configuration, when the position detection unit does not detect the position of the pump member in the reciprocating motion, the correction unit corrects the control information with the correction information, and the duty ratio increases, based on the duty ratio. Power is applied to the drive source. For this reason, even if the driving source starts moving slightly for some reason, the average voltage increases due to an increase in the duty ratio, and the driving source can be moved over the load. It becomes. For this reason, when such a load is acting on the drive source, it is possible to prevent a situation in which the drive source does not move indefinitely.

  Further, according to another invention, in addition to each of the above-described inventions, the drive control means stops the drive of the drive source for a specified time when the duty ratio exceeds a certain threshold value. In this case, when the duty ratio of the voltage exceeds a certain threshold value, the driving of the driving source is forcibly stopped. For this reason, even when a considerable temperature rise occurs in the drive source due to the application of a duty ratio voltage exceeding a certain threshold value, the drive source can be rested and the drive source can be cooled. Therefore, abnormal heating of the drive source can be prevented.

  In another invention, the pump control mechanism according to each of the above-described inventions is used in a printer, the storage means is a liquid container existing in the carriage, the liquid is ink, and the liquid supply source stores ink. It is a cartridge.

  When configured in this manner, in the printer, noise generated from a load portion such as a pump member and other friction portions can be suppressed. In other words, if the target information is set so that the noise generated from the load part deviates from the audible area, the generation of noise is reduced based on detection by the position detection means as the drive source is driven. Is possible. In addition, the generation of noise can be suppressed only by detection by the position detection means. This eliminates the need for an encoder or the like for detecting the drive speed of the drive source, and can suppress an increase in cost.

  Furthermore, another invention includes a pump unit that includes a pump member that applies air pressure by reciprocation, and a drive source that reciprocates the pump member and is controlled and driven based on control information. In the pump control method for feeding the liquid stored in the liquid supply source toward the storage means, an initial driving process for reciprocating the pump member by driving the drive source and a position in the reciprocating motion of the pump member are detected. A driving information calculation step for calculating driving information corresponding to a driving speed of a driving source for reciprocating the pump member, based on detection of the position of the pump member in the position detecting step, and a driving information calculating step And the target information corresponding to the target driving speed of the driving source stored in advance in the information storage means. Based on these comparisons, a correction information calculation step for calculating correction information for reducing the difference between the drive information and the target information when the drive source is driven next, and the control information are corrected A correction step of correcting with information, and a correction drive step of driving the drive source by supplying power controlled by the corrected control information to the drive source.

  In such a configuration, the position in the reciprocating motion of the pump member is detected in the position detection step, and the drive information of the drive source is calculated in the drive information calculation step based on the detection. Then, in the correction information calculation step, the calculated drive information is compared with the target information, and correction information for reducing the difference from the target information is calculated. In the correction step, the calculated correction information is Correct the control information. In the correction driving process, the driving source is controlled and driven based on the corrected control information.

  If it does in this way, it will become possible to control the noise which occurs from load parts, such as a pump member and other friction parts. In other words, if the target information is set so that the noise generated in the load part deviates from the audible area, the generation of noise can be reduced based on the detection in the position detection process as the drive source is driven. It becomes. In addition, it is possible to suppress the generation of noise only by detection in the position detection process. This eliminates the need for an encoder or the like for detecting the drive speed of the drive source, and can suppress an increase in cost.

  Hereinafter, an embodiment of a printer to which the pump control mechanism of the present invention is applied will be described with reference to FIGS. Note that the printer 10 of the present embodiment is an ink jet printer, but the ink jet printer may be an apparatus that employs any ejection method as long as the apparatus is capable of printing by ejecting ink.

  In the following description, the lower side refers to the installation surface 1 side where the printer 10 is installed, and the upper side refers to the side away from the installation surface 1. In addition, a direction in which a carriage 40 described later moves is a main scanning direction, and a direction perpendicular to the main scanning direction and a direction in which the print target 12 is conveyed is a sub-scanning direction. Further, a description will be given assuming that the side to supply the printing object 12 (upstream side of paper feeding) is the back side and the side to discharge the printing object 12 (downstream side of paper feeding) is the front side.

  The printer 10 includes a chassis 11 that contacts the installation surface 1, and various units are mounted on the chassis 11. The various units include a paper transport mechanism 20 that transports the printing object 12 by a paper feed motor (PF motor 22), and a carriage mechanism 30 that reciprocates the carriage 40 in the axial direction of the paper feed roller by a carriage motor (CR motor 35). Further, there are a cartridge mounting portion 60 for mounting a cartridge 62 for storing ink, a pump unit 70 for sending air to the cartridge 62 and pressurizing it, and the like, and a control portion 90 shown in FIGS. 2 and 6 exists.

  As shown in FIG. 2, the paper transport mechanism 20 includes rollers such as a paper feed roller (not shown) and a transport roller 21 and a paper feed motor (PF motor 22) for driving these rollers. ing. Further, the driving force of the PF motor 22 is transmitted through a transmission mechanism 23 composed of a plurality of gears and the like.

  As shown in FIGS. 1 and 2, the carriage mechanism 30 includes a carriage 40. The carriage mechanism 30 is supported by the support frame 31, the carriage shaft 34 that is supported by the support frame 31, and slidably holds the carriage 40, a carriage motor (CR motor 35), and the CR motor 35. A gear pulley 36 that is attached, an endless belt 37, and a driven pulley 38 that stretches the endless belt 37 between the gear pulley 36 are provided.

  The driven pulley 38 is attached to the side plate portion 33 on the other end side, and a gear pulley 36 is attached to one end side of the shielding plate portion 32. A belt 37, part of which is fixed to the carriage 40, is stretched between the driven pulley 38 and the gear pulley 36.

  As shown in FIG. 1, the support frame 31 includes a shielding plate portion 32 and side plate portions 33 that are bent toward the front side at both ends of the shielding plate portion 32. A pair of side plate portions 33 support a carriage shaft 34 for guiding the slide of the carriage 40 along the length of the chassis 11. A CR motor 35 for driving the gear pulley 36 is provided on the back side of the shielding plate portion 32.

  The gear pulley 36 is attached to the rotation shaft of the CR motor 35 on the back side of the shielding plate portion 32. Further, a platen 42 is provided in a portion of the chassis 11 closer to the support frame 31 (shielding plate portion 32). The platen 42 is attached so that the longitudinal direction thereof is along the longitudinal direction of the chassis 11. The upper surface of the platen 42 is a paper feed surface for feeding the printing object 12. In addition, what is conveyed on the upper surface of the platen 42 is not limited to the printing object 12, and may be a separate conveyance tray for holding the printing object 12.

  Further, a carriage 40 is provided so as to face the platen 42. Inside the carriage 40, the same number of liquid containers 41 as the number of colors of the cartridges 62 described later (for 6 colors in FIG. 2) can be mounted. One end side of a liquid conduit 43 such as a flexible tube is connected to each liquid container 41 as a storage means. Each color of the cartridge 62 is supplied to each liquid container 41 via the liquid conduit 43.

  The number of liquid containers 41 is not limited to the same number as the number of colors of the cartridge 62. For example, when the inside of the liquid container 41 is partitioned without omission, the number of the liquid containers 41 can be made smaller than the number of colors of the cartridge 62.

  As shown in FIG. 2, below the carriage 40, a print head unit 44 including a print head 45 protrudes toward the platen 42 side. A large number of nozzles 45 a shown in FIG. 4 are formed on the lower end side of the print head 45. Then, the ink supplied from the liquid container 41 is ejected from the nozzle 45a toward the printing object 12 as ink droplets.

  An external case (not shown) is attached to the chassis 11. The outer case covers each mechanism of the printer 10 and protects each mechanism from impact, dust, and the like.

  As shown in FIG. 1, the chassis 11 is provided with a cartridge mounting portion 60. The cartridge mounting portion 60 is provided on one end side and the other end side in the main scanning direction of the chassis 11 and is provided on the front side of the chassis 11. The cartridge mounting portion 60 is provided with a housing 61 for mounting the cartridge 62. In the present embodiment, the cartridge 62 as the liquid supply source includes, for example, K (black), LM (light magenta), LC (light cyan), C (cyan), M (magenta), and Y (yellow). Exists for color.

  As shown in FIGS. 4 and 5, one end of an air duct 86 is connected to the housing 61. Air supplied via the air duct 86 is distributed to each cartridge 62. Thereby, the ink existing in each cartridge 62 is sent into the liquid container 41 through the liquid conduit 43 by the pressure of the air. In addition, a number of liquid conduits 43 corresponding to the number of colors of the cartridge 62 are connected to the casing 61. The liquid conduit 43 receives the air pressure described above, and conducts the ink existing in the cartridge 62 toward the liquid container 41.

  As shown in FIG. 1, the chassis 11 is provided with a pump unit 70. The pump unit 70 is provided in a portion of the chassis 11 that does not interfere with the carriage mechanism 30 (for example, the front side and one end side of the chassis 11). As shown in FIG. 3, the pump unit 70 includes a casing 71, a pump motor 72, a gear train 73, a bellows pump 74, a check valve 75 (see FIG. 4), a pressure sensor 76, and a regulator. 77 and the position detection sensor 78 are the main components.

  The casing 71 is provided in a box shape that covers the lower side and the side by the bottom wall 71a and the four outer walls 71b, and the upper side is open. The casing 71 is a member that is installed on the chassis 11 while attaching each member of the pump unit 70. In the casing 71, a support plate 80 is provided so as to be substantially parallel to the outer wall 71b1.

  The support plate 80 is provided with a pump motor 72 corresponding to a drive source, which includes a drive gear 72b on a rotating shaft 72a. The pump motor 72 is a DC motor compatible with PWM (Pulse Width Modulation) control, and rotates the output gear 81 with electric power from a pump motor drive circuit described later. The casing 71 is provided with a gear train 73 composed of a plurality of driven gears. The gear train 73 is engaged with an output gear 81. The gear train 73 rotates the driving force generated by the pump motor 72 at a reduced speed and transmits it to the output gear 81. The output gear 81 is provided with a through hole 81a penetrating the center in the radial direction, and a guide shaft 88b described later is inserted through the through hole 81a.

  Of the gear train 73, the second gear 73b is provided with a rotation lever 82 coaxially. The rotary lever 82 is biased by the second gear 73b by a spring 83. With this urging force, the rotation lever 82 tries to rotate in synchronization with the second gear 73b. Here, when the rotary lever 82 rotates in the reverse direction, it can be engaged with the protruding piece 77 a of the regulator 77. Therefore, when the second gear 73b rotates in the reverse direction, the rotation lever 82 collides with the protruding piece 77a, and the protruding piece 77a can be pushed down.

  A bellows pump 74 as a pump member is attached between the support plate 80 and the outer wall 71b1. The bellows pump 74 is a bellows-like cylindrical member, and is formed of a flexible resin or the like. On one end side of the bellows pump 74, a small diameter portion 74a having a smaller diameter than the other portions is provided. Of the small-diameter portion 74 a, the end surface on one end side is an open opening 74 b so that air can be taken into the bellows pump 74. In the present embodiment, the other end side of the bellows pump 74 is not opened.

  Moreover, the one end side in which the opening part 74b exists among the bellows pumps 74 is received by the one end holding member 84, and this one end holding member 84 is attached to the outer wall 71b1. The one end holding member 84 includes an air outlet 85 that protrudes toward the other end side (support plate 80 side) of the bellows pump 74. The air lead-out part 85 is a part into which air is sent by the expansion and contraction operation of the bellows pump 74. Therefore, the air lead-out portion 85 includes an air intake port 85a through which air is sent from the bellows pump 74.

  The air outlet 85 is provided with an air outlet 85b, and one end of an air duct 86 is attached to the air outlet 85b. The other end of the air duct 86 is connected to the cartridge 62, and air can be sent into the cartridge 62. The air outlet 85 is provided with an engaging portion 85c that enters the bellows pump 74 from the opening 74b. When the engaging portion 85c enters and engages the bellows pump 74, even if the bellows pump 74 contracts, the air inside the bellows pump 74 is prevented from leaking.

  Further, a spring 87 is provided between the air outlet 85 and one end side of the bellows pump 74. The spring 87 is provided so as not to be detached by the spring locking claw 85d of the air outlet portion 85. The spring 87 is provided on the outer peripheral side of the engaging portion 85c, and applies an urging force toward one end side (opening side) of the bellows pump 74 toward the other end side. Therefore, when the bellows pump 74 is in the extended state, the biasing force of the spring 87 causes the one end side of the bellows pump 74 to receive a biasing force toward the other end side, and the opening 74b is separated from the engaging portion 85c. Thereby, when the bellows pump 74 is in the extended state, air can be introduced into the bellows pump 74.

  In the process in which the bellows pump 74 shifts to the contracted state, the opening 74b is engaged with the engaging portion 85c again so that the air taken into the bellows pump 74 is not leaked to the outside. Thereafter, when the bellows pump 74 is further contracted, the air inside the bellows pump 74 is pushed out of the bellows pump 74 to the air pipe 86, and the air pressure generated by the pushing out of the air is supplied to the cartridge via the air pipe 86. Acts inside 62.

  In addition, a check valve 75 (see FIG. 4) that prevents the backflow of air from the bellows pump 74 toward the cartridge 62 and can maintain the pressure is provided in the middle of the air duct 86. The check valve 75 may be provided in the middle of the air pipe 86, but may be configured to be incorporated in the one end holding member 84.

  The other end holding member 88 is provided on the other end side of the bellows pump 74. The other end holding member 88 has a second end receiving portion 88a and a guide shaft 88b, and both are integrally provided. Among these, the other end receiving portion 88 a receives the other end side of the bellows pump 74. The guide shaft 88b is inserted into the through hole 81a of the output gear 81 described above, and is provided so as to be freely inserted through the through hole 81a.

  Further, as shown in FIG. 7, a spiral groove 88c is formed in the guide shaft 88b. An engaging protrusion 81b protruding from the inner wall surface of the through hole 81a enters the spiral groove 88c. Therefore, if the engagement protrusion 81 b rotates with the rotation of the output gear 81, the guide shaft 88 b is pushed by the engagement protrusion 81 b and reciprocates along the axial direction of the bellows pump 74. In this way, the expansion / contraction operation of the bellows pump 74 can be executed. The spiral groove 88c describes a closed loop that reciprocates the other end holding member 88 when the output gear 81 is rotated in one direction.

  A pressure sensor 76 is attached to the casing 71. The pressure sensor 76 is a reflective sensor including a light emitting element and a light receiving element, and includes a lid-like member (not shown) and a thin film member such as cellophane (also not shown). When air pressure is applied to the thin film member, the thin film member expands. Due to the swelling, the thin film member comes close to the lid-like member. When close to a certain distance or less, the light emission from the light emitting element can be detected by the light receiving element, and the pressure is detected.

  The air that has passed through the pressure sensor 76 is sent to the regulator 77. The regulator 77 includes a protruding piece 77a. When the protruding piece 77a is pushed downward by the rotating lever 82, the regulator 77 is provided so as to release the pressure. Further, the regulator 77 automatically releases the pressure when a pressure higher than a predetermined pressure is applied.

  When the second gear 73b rotates to the forward rotation side, the rotation lever 82 tries to move upward, and the rotation lever 82 does not engage with the protruding piece 77a. However, when the gear train 73 rotates in the reverse direction, the rotation lever 82 tries to move downward, collides with the protruding piece 77a, and pushes it down. In this way, it is possible to switch the protruding piece 77a.

  In addition, a position detection sensor 78 corresponding to the position detection means is attached to the casing 71. The position detection sensor 78 has a rotatable detection lever 78a, and the detection lever 78a can come into contact with the other end receiving portion 88a. Further, the detection lever 78a protrudes from the main body 78b in which a switch for transmitting a High (H) / Low (L) signal is incorporated, and by switching the H / L switch, the detection lever 78a The extension position can be detected. Here, when the bellows pump 74 is in the contracted state, the detection lever 78 a is not pushed by the other end receiving portion 88 a and is positioned on one end side close to the bellows pump 74. However, when the bellows pump 74 is in the extended state, the detection lever 78a is pushed to the other end side by the movement of the other end receiving portion 88a, and the signal is switched. Thereby, the extended position of the bellows pump 74 can be detected.

  In the present embodiment, the position detection sensor 78 is configured to be switched between H and L at the position where the bellows pump 74 is extended most. In the present embodiment, the H signal is transmitted when the bellows pump 74 is extended to the maximum and the detection lever 78a is pushed in.

  Next, the configuration of the control unit 90 will be described with reference to FIG. The control unit 90 includes a bus 90a, a CPU 91, a ROM 92, a RAM 93, a character generator (CG) 94, an I / F dedicated circuit 95, a DC unit 96, a PF motor driving circuit 97, a CR motor driving circuit 98, a head driving circuit 99, a pump. A motor drive circuit 100, a nonvolatile memory 101, and the like are provided. In addition, the control unit 90 functions as a drive information calculation unit, a correction information calculation unit, a correction unit, a drive control unit, and a timer unit by cooperation of these configurations.

  The CPU 91 and the DC unit 96 are provided with various sensors (not shown) and the like (a rotary encoder that detects the amount of rotation of the transport roller 21, a linear encoder that detects the amount of movement of the carriage 40, and the start and end of the print object 12. Output signals of a paper detection sensor to be detected, a PW sensor for detecting the length (width) of the print target 12 in the sub-scanning direction, a power supply SW for turning on / off the printer 10, and the like are input.

  The CPU 91 performs arithmetic processing for executing a control program for the printer 10 stored in the ROM 92, the nonvolatile memory 101, and the like, and other necessary arithmetic processing. The ROM 92 stores a control program for controlling the ink jet printer 10 and data necessary for processing. In the present embodiment, the ROM 92 also stores target information corresponding to the target rotational speed of the pump motor 72. Therefore, the ROM 92 corresponds to information storage means. This target information is made to correspond to the rotation speed of the pump motor 72 so that the noise generated from the pump unit 70 does not reach the audible region.

  In the present embodiment, there are three modes for driving the pump motor 72 as described later. Therefore, there are as many control programs for the printer 10 as possible corresponding to the mode. The I / F dedicated circuit 95 has a built-in parallel interface circuit, and can receive a print signal PS supplied from the computer 110 via the connector 111.

  The RAM 93 is a memory that temporarily stores a program being executed by the CPU 91 or data being calculated. The nonvolatile memory 101 is a memory for storing various data that needs to be retained even after the inkjet printer 10 is turned off. As will be described later, the duty ratio of the voltage when stopping the driving of the pump motor 72 is also stored in the nonvolatile memory 101. However, these control data, target information, and the like may be stored in a separate storage area.

  The DC unit 96 is a control circuit for performing speed control of the PF motor 22 and the CR motor 35 which are DC motors. The DC unit 96 performs speed control of the PF motor 22 and the CR motor 35 based on the control command sent from the CPU 91, the output signal of the rotary encoder, the output signal of the linear encoder, and the output signal of the paper detection sensor. The motor control signal is transmitted to the PF motor driving circuit 97 and the CR motor driving circuit 98 based on the calculation result.

  The PF motor drive circuit 97 controls the drive of the PF motor 22 based on the motor control signal from the DC unit 96. The PF motor 22 serves as a power source for conveying the printing object 12. The CR motor drive circuit 98 controls and drives the CR motor 35 based on the motor control signal from the DC unit 96. The PF motor 22 and the CR motor 35 can be held in a stopped state.

  The head drive circuit 99 controls and drives the piezo elements present in the print head 45 based on a signal for performing drive control from the CPU 91. The pump motor drive circuit 100 controls and drives the pump motor 72. The pump motor 72 is also a DC motor, and when a pulse voltage having an optimum frequency for driving is applied, drive control by PWM control can be easily performed.

  Here, PWM control refers to the width of the pulse voltage H applied to the DC motor by a PWM signal that quickly switches between the voltage H and L (hereinafter, the width of H in one cycle of the pulse voltage is referred to as the duty ratio). .) Is adjusted, the average voltage of the pulse voltage is adjusted, and the drive control of the DC motor is performed. The Duty ratio corresponds to control information. A correction amount α1 described later corresponds to correction information. In such PWM control, there are a method using a uniform pulse having a uniform pulse width and a method using a non-uniform pulse in which the pulse width changes. Any pulse signal may be used. Further, any pulse signal may be used by various combinations of adjusting the duty ratio of the voltage pulse and the period of the voltage pulse.

  In addition, each structure in the above-mentioned control part 90 is connected by the bus | bath 90a which is a signal line. The CPU 91, the ROM 92, the RAM 93, the CG 94, the I / F dedicated circuit 95, the nonvolatile memory 101, and the like are connected to each other by the bus 90a, and data can be exchanged between them.

  The case where the pump motor 72 is first driven using the above configuration will be described with reference to FIG. In the present embodiment, the control unit 90 can drive the pump motor 72 in three modes. Here, the three modes are the "quiet mode", which is the quietest, the "medium mode", which is moderately quiet but also places importance on speed, and the "speed mode" which places importance on speed without worrying about noise. There are three types. In the following description, among the three modes, the quietest “quiet mode” for suppressing noise generated from the pump unit 70 will be described.

  Note that the case where the pump motor 72 is driven first corresponds to the case where the printer 10 is started first. However, when the cartridge 62 is replaced and the pressure is equal to the atmospheric pressure, or for a long period of time. A case where the printer 10 is used from a state where the printer 10 is not used may be included.

  Step S10: The power supply SW of the printer 10 is turned on, and the operation of the printer 10 is started. Then, the pump motor 72 is activated, and the reciprocating motion of the bellows pump 74 is started (corresponding to the initial driving process). Here, the pump motor 72 is driven based on control data (fixed value) stored in the nonvolatile memory 101 in the first drive. This fixed value relates to the prescribed duty ratio of the pulse voltage, and is a value that does not change after that.

  By the way, when the pump motor 72 is first activated, the time until the first H signal is transmitted often does not correspond to one cycle. That is, when the other end holding member 88 pushes in the detection lever 78a of the position detection sensor 78 before the printer 10 is activated, it is possible to accurately measure one cycle from the beginning. However, when the other end holding member 88 does not push in the detection lever 78a, it is impossible to accurately measure the time of one cycle in the first cycle.

  Therefore, in this embodiment, the first H signal is transmitted (corresponding to the first cycle) and the first H signal and the second H signal are transmitted (corresponding to the second cycle). ), The voltage duty ratio drives the pump motor 72 using the fixed value described above. For this reason, the duty ratio of the voltage of the pump motor 72 is changed by measuring the period using a correction amount α1, which will be described later, in the third period (the H signal is transmitted in the second time and then the H ratio in the third time. The time until the signal is transmitted). That is, the time from the H signal to the H signal can be accurately measured only after the second period, but the second period can be accurately projected in the third period.

  In addition, when the time of the 1st period can be measured correctly, you may make it project measurement time in the 2nd period. Further, each cycle of driving the pump motor 72 (time between adjacent H signals), the number of rotations in that cycle (drive speed), and the duty ratio of the voltage in that cycle correspond to drive information. Similarly, the target information is a target cycle of the pump motor 72 and the number of rotations in that cycle.

  The pump motor 72 is driven for two cycles (time until the position detection sensor 78 transmits the second H signal) based on the pulse voltage having the fixed duty ratio. In addition, at the time of start-up, an initial load is added to the pump motor 72 more than after several cycles of operation. For this reason, the duty ratio at startup is normally set high.

  Step S11: The CPU 91 determines whether or not an H signal has been received from the position detection sensor 78 (corresponding to the position detection step). That is, when the detection lever 78 a is pushed by the other end receiving portion 88 a, the position detection sensor 78 transmits a first H signal to the control portion 90. In this determination, when it is determined that the H signal has been received (in the case of Yes), the process proceeds to step S14 described later. If it is determined that the H signal is not received (in the case of No), the process proceeds to the next step S12.

  Step S12: When the CPU 91 determines that the first H signal has not been received, the CPU 91 determines whether or not a predetermined time limit has elapsed. In this determination, when it is determined that the time limit has elapsed (in the case of Yes), the process proceeds to the next step S13. When it is determined that the time limit has not elapsed (in the case of No), the process returns to step S11 described above.

  Step S13: When the CPU 91 determines that the time limit has passed (Yes in step S12), the CPU 91 adds the correction amount α2 to the voltage duty ratio. That is, there is a case where the first H signal is not transmitted even if waiting for a predetermined time due to some trouble (for example, when a large load is applied due to solidification of ink or the like). In this case, it is not possible to shift to the next cycle simply by waiting for transmission of the H signal. Therefore, if the H signal is not transmitted even after a certain time limit elapses, the CPU 91 forcibly adds the correction amount α2 to determine the duty ratio of the voltage, and supplies the pump motor 72 with the voltage of the duty ratio. Apply.

  The correction amount α2 added in step S13 is a value that increases the duty ratio of the voltage. Therefore, for example, when the bellows pump 74 cannot start due to a shortage of torque, the problem can be solved, and power necessary for the bellows pump 74 to start moving can be supplied. In addition, after step S13, the process returns to step S11 described above. It should be noted that the correction amount α2 given after the time limit has elapsed may be increased stepwise within a certain limit as time elapses.

  Step S14: When the CPU 91 determines that the first H signal has been received, the CPU 91 subsequently determines whether or not the second H signal has been received (corresponding to the position detection step). In this determination, when it is determined that the H signal has been received (in the case of Yes), the process proceeds to the next step S15. On the other hand, when it is determined that the H signal is not received (in the case of No), the process returns to the step S14 again.

  Step S15: The CPU 91 calculates the period of the bellows pump 74 measured using the position detection sensor 78 (corresponding to the drive information calculation step). Here, the period is the time from when the position detection sensor 78 transmits the H signal first to when the position detection sensor 78 transmits the H signal second. In addition, when step S21 to be described later has elapsed, the calculated cycle is that the H signal newly transmitted by the position detection sensor 78 after adding the correction amount α1 and the H signal immediately before the new H signal. It will be time between.

  Step S16: The CPU 91 determines whether or not the rotation speed of the pump motor 72 corresponding to the cycle is within a predetermined range based on the calculation of the cycle obtained in step S15 described above (correction information calculation). Corresponding to part of the process). That is, based on the calculated cycle, the CPU 91 calculates the rotation speed of the pump motor 72 that directly corresponds to the cycle, and whether or not the calculated rotation speed of the pump motor 72 is within a target appropriate range. Determine whether. In this determination, when it is determined that it is within the appropriate range (in the case of Yes), the process proceeds to step S19 described later, and when it is determined that it is not within the appropriate range (in the case of No), the process proceeds to next step S17. To do. The appropriate range of the rotational speed is a range between the upper limit of the rotational speed at which the generated noise is not so loud and the lower limit of the rotational speed calculated from the allowable time until the pressure reaches the threshold value. .

  Step S17: The CPU 91 calculates the correction amount α1 from the calculated rotation speed and the target information stored in the nonvolatile memory 101 (corresponding to a part of the correction information calculation step). That is, the correction amount α1 is calculated so that the pump motor 72 has a rotation speed within an appropriate range. That is, if the maximum value of the rotation speed of the pump motor 72 (the rotation speed of the pump motor 72 in a light load state where the bellows pump 74 is not pressurized) is controlled to be close to the target value within the appropriate range. The noise generated from the mechanical part can be reduced below the target noise level. Therefore, in step S17, the correction amount α1 to be added to the duty ratio is determined from the relationship between the maximum value of the rotation speed at the current voltage duty ratio and the target rotation speed.

  A table of the correction amount α1 corresponding to the rotation speed of the pump motor 72 may be stored in the ROM 92 in advance. In this case, the table of the correction amount α1 can be obtained by experiments or the like, and the table is stored in a storage part such as the ROM 92. In this case, the correction amount α1 is calculated by calling the correction amount α1 having the closest rotation number of the table to the calculated rotation number of the pump motor 72.

  Further, the correction amount α1 may be obtained sequentially by calculation without storing the correction amount α1 table in advance. In this case, the correction amount α1 is calculated based on the prediction that the initial rotational speed of the pump motor 72 changes proportionally in response to a change in the mechanical load. That is, since the characteristics of the pump motor 72 are known in advance, the mechanical load can be calculated from the initial rotational speed of the pump motor 72, and the rotational speed of the pump motor 72 is set to the target rotational speed. The correction amount α1 can also be calculated.

  As described above, when the correction amount α1 is added, when the difference between the calculated rotational speed of the pump motor 72 and the target information (target rotational speed) is large, the correction amount α1 is As the difference becomes larger and the difference becomes smaller, the correction amount α1 becomes smaller.

  Step S18: The CPU 91 adds the above-described correction amount α1 to the voltage duty ratio (corresponding to the correction step). In other words, in the next period (third period; when step S18 has been performed once, the period from the last reception of the H signal to the reception of a new H signal), this correction amount α1 is added. The duty ratio of the measured voltage is applied to the pump motor 72. In this case, the width of the voltage per pulse varies by the amount to which the correction amount α1 is added.

  Step S19: The pump motor drive circuit 100 applies the duty ratio of the voltage added with the correction amount α1 to the pump motor 72 to drive the pump motor 72 (corresponding to the correction drive step).

  Step S20: The CPU 91 determines whether or not a signal notifying that the pressure value has exceeded the threshold value has been received from the pressure sensor 76. This determination is made by receiving an H signal or an L signal when the threshold value is exceeded, as in the position detection sensor 78 described above. When it is determined that the pressure value exceeds the threshold value (in the case of Yes), the process proceeds to step S22. When it is determined that the pressure value does not exceed the threshold value (in the case of No), the process proceeds to step S21.

  Step S21: The CPU 91 determines whether or not a new (next) H signal is received from the position detection sensor 78 after the correction amount α1 is added. In this determination, when it is determined that the H signal has been received (in the case of Yes), the process returns to step S15 described above. On the other hand, when it is determined that the H signal is not received (in the case of No), the process returns to before step S21 again.

  Step S22: The CPU 91 stores the duty ratio of the voltage to which the latest correction amount α1 is added in the nonvolatile memory 101. It is preferable that the duty ratio is called at the next start-up and the pump motor 72 is driven based on the duty ratio.

  Step S23: The CPU 91 stops the operation of the pump motor 72. In this case, the pump motor 72 is stopped at the end where the other end holding member 88 pushes the detection lever 78a. In this way, when the driving of the pump motor 72 is started next time, the accurate period measurement can be performed from the stage where the CPU 91 first receives the H signal.

  However, due to some trouble, the bellows pump 74 may stop at an intermediate position where the position detection sensor 78 is not pushed. Corresponding to this case, it is preferable that the time of the second cycle, which is accurately measured, be projected in the third cycle when the pump motor 72 is operated thereafter.

  Note that the duty ratio of the voltage applied to the pump motor 72 may exceed a certain threshold and become higher, for example, when a child performs some mischief. In this case, if the drive of the pump motor 72 is continued while the duty ratio is high, the amount of heat generated from the pump motor 72 becomes large, the pump motor 72 is abnormally heated, and causes a failure such as disconnection. . In this case, after the drive is stopped in step S22, the operation of the pump motor 72 may be stopped for a specified time.

  Through the above steps, when the pump motor 72 is first driven, the pump motor 72 continues to be driven for a predetermined time even when the rotational speed of the pump motor 72 deviates from the target rotational speed. Then, the pump motor 72 will eventually converge to the target rotational speed.

  According to the printer 10 having such a configuration, the maximum value of the rotational speed of the pump motor 72 can be adjusted to be equal to or less than the target rotational speed of the pump motor 72 at the initial stage of movement. Thereby, it is possible to suppress noise generated from the load portion such as the bellows pump 74 and other friction portions. That is, as described above, since the target information is set so that the noise generated from the load portion deviates from the audible area, as the pump motor 72 is driven, based on the detection by the position detection sensor 78, Noise generation can be reduced. That is, by controlling as described above, it is possible to reduce the frequency of noise generated from a load portion such as a gear meshing / sliding portion. Therefore, conventionally, the frequency of the load portion that has reached the audible area and is noisy does not reach the audible area, so that the user's annoyance is greatly reduced.

  In the printer 10, the mechanical load fluctuates due to the variation in friction depending on the years used, the ink viscosity, and the like, and the initial rotational speed of the pump motor 72 changes. However, even when the initial rotational speed changes, the pump motor 72 can be converged to the vicinity of the target rotational speed only by driving the pump motor 72 for several cycles. Further, in the printer 10, even if the initial load varies, the relationship between the rotation speed of the pump motor 72 and the generated noise is substantially the same. Therefore, if the rotational speed of the pump motor 72 is appropriately controlled, the noise generated from the mechanical part can be reduced to a target noise level or less.

  In addition, the generation of noise can be suppressed only by detection by the position detection sensor 78. For this reason, an encoder or the like for detecting the driving speed of the pump motor 72 is not required, and an increase in cost can be suppressed.

  Further, in the control of the pump motor 72, PWM control for changing the duty ratio of the pulse voltage is performed. Therefore, the rotational speed of the pump motor 72 can be adjusted only by adjusting the duty ratio of the pulse voltage, and the rotational speed of the pump motor 72 can be accurately controlled while being simple.

  In the present embodiment, when the pressure exceeds the threshold value by the pressure sensor 76, the driving of the pump motor 72 is stopped. Therefore, it is possible to prevent the bellows pump 74 from applying excessive pressure to the cartridge 62 and overflowing the ink from the liquid container 41. That is, an appropriate amount of ink can be supplied from the cartridge 62 to the liquid container 41, and an appropriate amount of ink can be stored in the liquid container 41.

  Further, the position detection sensor 78 detects the position of the bellows pump 74 in the reciprocating motion on the extension end side of the bellows pump 74, and transmits an H signal. Therefore, when the position detection sensor 78 once detects the position of the bellows pump 74 and again detects the position of the bellows pump 74, the start and end points of one cycle of the bellows pump 74 can be measured. And by measuring the time between these, the time of 1 cycle of the bellows pump 74 can be measured correctly.

  In addition, in the above-described embodiment, the position detection sensor 78 stops the driving of the pump motor 72 on the extended end side of the bellows pump 74. Therefore, when the pump motor 72 is driven next, if the CPU 91 receives the first H signal from the position detection sensor 78, the time until the detection becomes the first cycle. That is, at the initial position detection stage, accurate cycle measurement can be performed, and calming can be achieved more quickly.

  In the present embodiment, the correction amount α1 is added from the third cycle of the reciprocating motion of the pump member. In this case, even when the bellows pump 74 is stopped in the middle of the reciprocating motion, the time between the detection of the first H signal and the detection of the second H signal (second cycle time) Can be measured accurately. For this reason, if the correction amount α1 calculated from the second period is added in the third period, the pump unit 70 can be satisfactorily stabilized.

  In the present embodiment, when the CPU 91 determines that a predetermined time has elapsed, the correction amount α2 is added to the voltage duty ratio. Therefore, even if the first H signal is not transmitted even if waiting for a predetermined time due to some trouble (for example, when a large load is applied due to solidification of ink or the like), the correction amount α2 If the voltage is increased by adding the pressure, the pump motor 72 can move over the load. Accordingly, when such a load is applied to the pump motor 72 (the bellows pump 74), it is possible to prevent a situation in which the pump motor 72 (the bellows pump 74) does not start moving indefinitely.

  Although one embodiment of the present invention has been described above, the present invention can be variously modified in addition to this. This will be described below.

  Further, in the above-described embodiment, fixed values stored in the ROM 92 are used for the voltages of the first cycle and the second cycle applied to the pump motor 72. However, when the printer 10 is started, if there is a situation such as fluctuations in the rotational speed being large and unstable each time the printer 10 is started, the fixed value is changed corresponding to the next start of the printer 10. Anyway. Further, the position detection sensor 78 may be corrected immediately based on the time during which the H signal is transmitted within one cycle. That is, when the H signal transmission time is shorter than the specified time when the CPU 91 is started, the CPU 91 immediately changes the duty ratio to decrease, or when the H signal transmission time is longer than the specified time, the CPU 91 It is also possible to change the duty ratio to increase immediately.

  In the above-described embodiment, the case where a DC motor is used as the pump motor 72 has been described. However, the pump motor 72 is not limited to a DC motor. If the control by the PWM method can be performed, the present invention can be applied to a drive mechanism using, for example, an AC motor or the like.

  When adjusting the duty ratio of the voltage, the correction amount α1 may be changed according to the remaining amount of ink in the cartridge 62. That is, the time until the pressure sensor 76 exceeds the threshold value differs depending on the remaining ink amount. For example, when the cartridge 62 is new, the operation time of the bellows pump 74 may be short. In such a case, the correction amount α1 may be adjusted so as to reduce the voltage duty ratio in accordance with the information on the ink remaining amount.

  Furthermore, in the above-described embodiment, a case has been described in which ink is used as the liquid, the cartridge 62 is used as the liquid supply source, and the liquid container 41 is used as the storage unit. However, the liquid is not limited to ink, and may be a processing liquid for performing various processes such as a semiconductor, a cleaning liquid, or the like. In these cases, the liquid supply source is not the cartridge 62 but a tank for storing the processing liquid and the cleaning liquid.

  In the above-described embodiment, the driving of the pump motor 72 is stopped when the pressure measured by the pressure sensor 76 exceeds a threshold value. However, instead of the pressure sensor 72, a sensor for detecting the amount of ink is provided on the liquid container 41 side, and the CPU 91 stops driving the pump motor 72 when the sensor detects that the amount of ink is sufficient. You may make it let it.

  In the above-described embodiment, the case where the pump control mechanism is applied to the home printer 10 has been described. However, the pump control mechanism of the present invention is not limited to being applied to the printer 10 and may be applied to a large business printer. The present invention may also be applied to devices other than printers, such as air conditioner compressors.

  Further, in the above-described embodiment, the drive information is each cycle, the number of rotations in each cycle, and the duty ratio of the voltage in each cycle. Further, the target information is a target cycle of the pump motor 72 and the number of rotations in that cycle. However, the drive information / target information is not limited to this, and for example, the ink flow rate may be used as the drive information / target information.

  In the above-described embodiment, the correction is described for the case where the correction amount α1 is added (including the case where a negative value is added). However, when the correction amount α1 is a predetermined correction coefficient, the duty ratio may be multiplied by the correction coefficient. Further, the control information, the correction information, and the like are not limited to the case where a certain numerical value is added, and may be information that changes the control timing executed by the control program.

1 is a perspective view illustrating a configuration of a printer according to an embodiment of the present invention. FIG. 2 is a schematic diagram illustrating a configuration of a printer. It is a top view which shows the mechanical structure of a pump unit. It is the schematic which shows the pump unit of an expansion | extension state, and a pressurization relationship. It is the schematic which shows the pump unit of a contracted state, and a pressurization relationship. It is a block diagram of the control part which performs various control of a printer. It is a disassembled perspective view which shows the structure of an other end holding member and an output gear. It is a flowchart which shows control of a pump motor.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Printer, 12 ... Print object, 22 ... PF motor, 35 ... CR motor, 40 ... Carriage, 41 ... Liquid container (corresponding to storage means), 42 ... Platen, 60 ... Cartridge mounting part, 62 ... Cartridge (liquid) 70 ... pump unit, 72 ... pump motor (corresponding to drive source), 74 ... bellows pump (corresponding to pump member), 75 ... check valve, 76 ... pressure sensor, 77 ... regulator, 78 ... Position detection sensor (corresponding to position detection means), 86 ... air pipe, 88 ... other end holding member, 90 ... control unit, 92 ... ROM (corresponding to information storage means), 101 ... nonvolatile memory

Claims (9)

A pump member for applying air pressure by a reciprocating motion and a drive source for reciprocating the pump member and controlled and driven based on control information are provided, and the pump member is reciprocated by driving the drive source to store. A pump unit for feeding liquid stored in the liquid supply source toward
Position detecting means for detecting a position in the reciprocating motion of the pump member;
Information storage means for storing target information corresponding to the target drive speed when driving the drive source;
Driving information calculating means for calculating driving information corresponding to the driving speed of the driving source that reciprocates the pump member based on the position detection of the pump member in the position detecting means; the driving information and the target A correction for calculating correction information for the control information for reducing the difference between the drive information and the target information when the drive source is next driven based on the comparison with the information. Information calculation means;
Correction means for correcting the control information input to the drive source from the third cycle of reciprocation of the pump member with the correction information;
A pump control mechanism comprising:   The control information is a duty ratio for performing PWM control on a pulse voltage applied to the drive source, and the correction information is a value for changing the duty ratio of the pulse voltage in the PWM control. The pump control mechanism according to claim 1.   3. The pump control mechanism according to claim 1, wherein the position detection unit detects a position in a reciprocating motion of the pump member on an extension end side of the pump member.   The drive control means for stopping / starting the drive of the drive source is provided, and the drive control means stops / starts the drive source based on the measurement of the air pressure by a pressure sensor. The pump control mechanism according to any one of 1 to 3.   5. The pump control mechanism according to claim 4, wherein the drive control means stops the drive of the drive means on the extended end side. The drive information calculation means includes timer means for measuring a time until the position detection means detects, and the position detection means can be used even if the time measurement by the timer means exceeds a specified time limit. The said correction | amendment means correct | amends the said control information with the said correction information which raises the said Duty ratio, when the position in the reciprocation of a member is not detected, The any one of Claim 1 to 5 characterized by the above-mentioned. Pump control mechanism. Said drive control means when said Duty ratio exceeds a certain threshold, the pump control according to any one of claims 3 6, characterized in that only the stop specified time the driving of the driving source mechanism. While using the pump control mechanism of any one of Claim 1 to 7 ,
The storage means is a liquid container present in a carriage;
The liquid is ink;
The liquid supply source is a cartridge for storing ink;
A printer characterized by that. A pump unit that includes a pump member that applies air pressure by reciprocating motion, and a drive source that reciprocates the pump member and that is controlled and driven based on control information. In the pump control method for feeding the liquid stored in the liquid supply source,
An initial drive step of reciprocating the pump member by driving the drive source;
A position detecting step for detecting a position in the reciprocating motion of the pump member;
A drive information calculation step for calculating drive information corresponding to the drive speed of the drive source that reciprocates the pump member based on the position detection of the pump member in the position detection step;
The drive information calculated by the drive information calculation step is compared with the target information corresponding to the drive speed that is the drive target of the drive source stored in advance in the information storage unit, and based on these comparisons Then, a correction information calculation step for calculating correction information for reducing the difference between the drive information and the target information when the drive source is driven next,
A correction step of correcting the control information with the correction information from the third period of reciprocation of the pump member ;
A correction driving step of driving the driving source by supplying the power controlled by the control information after correction to the driving source;
A pump control method comprising:

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