Printing apparatus

Abstract

To provide a printer which can reduce reduction in the printing efficiency due to power outage.SOLUTION: A printer 10 comprises: a printing unit 11; a power storage unit 62 which can store the power from an external power source; a plurality of voltage conversion units 65 which are provided in parallel to each other between the power storage unit 62 and the printing unit 11, and convert the voltage of the power input from the power storage unit 62 into mutually-different voltages according to the operation voltages of the plurality of processing operations to output the voltage to the printing unit 11; a switching unit 64 which switches the input destination of the power from the power storage unit 62 to at least one voltage conversion unit 65 in the plurality of voltage conversion units 65; and a control unit 50. The control unit 50 detects the presence / absence of the occurrence of power outage about an external power source, and executes an uncompleted operation by switching the input destination of the power from the power storage unit 62 to at least one of the plurality of voltage conversion units 65 according to the operation voltage of the uncompleted operation in the plurality of processing operations when detecting the occurrence of power outage.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a printing apparatus.

Background Art

[0002] As a conventional printing apparatus, for example, an inkjet recording apparatus of Patent Document 1 is known. This inkjet recording apparatus includes a recording head that discharges ink onto a recording medium and an internal power source. When a power failure occurs, it determines whether to interrupt the cleaning process according to the remaining power of the internal power source.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In such an inkjet recording apparatus, if image recording is in progress by the recording head during a power failure, the image recording is interrupted, and it is determined whether the remaining power of the internal power source is sufficient for the cleaning process. If the remaining power is not sufficient for the cleaning process, the cleaning process is interrupted. However, if the image recording and the cleaning process are interrupted uniformly in this way, there is a risk of reducing the printing efficiency.

[0005] In view of such a situation, an object of the present invention is to provide a printing apparatus capable of reducing the decrease in printing efficiency due to a power failure.

Means for Solving the Problems

[0006] A printing apparatus according to one aspect of the present invention includes a printing unit having a head that ejects ink from a nozzle, and performing a plurality of processing operations which include a printing operation relating to printing on a printing medium with the ejected ink and a backup operation relating to the backup of the printing operation, and which have different operating voltages from each other; a power storage unit capable of storing power from an external power supply; a plurality of voltage conversion units provided in parallel between the power storage unit and the printing unit, which convert the voltage of the power input from the power storage unit into a plurality of voltages which are different from each other according to the operating voltages of the plurality of processing operations and output them to the printing unit; a switching unit which switches the input destination of the power from the power storage unit to at least one of the plurality of voltage conversion units; and a control unit, wherein the control unit detects whether or not a power outage has occurred with respect to the external power supply, and if a power outage has occurred, it switches the input destination of the power from the power storage unit to at least one of the plurality of voltage conversion units according to the operating voltage of an incomplete operation among the plurality of processing operations, and executes the incomplete operation. [Effects of the Invention]

[0007] The present invention has the effect of providing a printing apparatus that can reduce the decrease in printing efficiency caused by power outages.

[0008] The above-mentioned objectives, other objectives, features, and advantages of the present invention will become apparent from the following detailed description of preferred embodiments with reference to the accompanying drawings. [Brief explanation of the drawing]

[0009] [Figure 1] This figure schematically shows a printing apparatus according to an embodiment of the present invention. [Figure 2] This is a schematic diagram of the head shown in Figure 1. [Figure 3] Figure 1 is a functional block diagram of the printing apparatus. [Figure 4] This diagram schematically shows the electrical connections of the printing apparatus shown in Figure 1. [Figure 5] This graph shows the relationship between voltage and power in the energy storage unit. [Figure 6]Figure 1 is a flowchart showing an example of a control method for a printing device. [Figure 7] This diagram schematically shows the electrical connections of a printing apparatus in a modified configuration. [Figure 8] Figure 7 is a flowchart showing an example of a control method for the printing device. [Figure 9] This graph shows the change in voltage of the energy storage unit over time during charging. [Modes for carrying out the invention]

[0010] <Printing device configuration> A printing apparatus 10 according to one embodiment of the present invention, as shown in Figure 1, is a device that ejects ink from the nozzles 21 of the head 20 onto a printing medium A and prints an image on the printing medium A using the ink. Below, an example of applying the printing apparatus 10 to an inkjet printer will be described, but the printing apparatus 10 is not limited to this. The printing medium A is, for example, a sheet of paper or cloth.

[0011] The printing apparatus 10 is a serial head type and comprises a printing unit 11, a platen 12, a tank 13, and a control unit 50. The printing unit 11 has a head 20, a transport device 30, and a scanning device 40. The direction in which the printing medium A is transported by the transport device 30 is referred to as the front-rear direction. The direction in which the scanning device 40 moves the head 20, which intersects (for example, orthogonally) the front-rear direction, is referred to as the left-right direction. Furthermore, the direction that intersects (for example, orthogonally) the front-rear direction and the left-right direction is referred to as the up-down direction. However, the arrangement of the printing apparatus 10 is not limited to this. The printing apparatus 10 may also be a line head type. In this case, the printing apparatus 10 does not have a scanning device 40, and the head 20 does not move and has a dimension longer than the length of the printing medium A in the left-right direction.

[0012] The printing device 10 has a printing area and a maintenance area that are arranged horizontally relative to each other inside. The platen 12 is located in the printing area of ​​the printing device 10, has a flat top surface, and defines the distance between the printing medium A placed on its top surface and the bottom surface of the head 20 which is provided opposite it. The tanks 13 are containers for storing ink, and a plurality of them are provided in the printing device 10 depending on the type of ink. For example, four tanks 13 store cyan ink, yellow ink, magenta ink, and black ink, respectively. Each tank 13 is connected to the head 20 by a tube, and the ink is supplied to the corresponding nozzle 21 in the head 20 via the tube.

[0013] <Print section> The printing unit 11 performs multiple processing operations, each with a different operating voltage, including printing operations related to printing on the printing medium A with ejected ink, and backup operations related to backing up the printing operations. For example, in addition to the head 20, transport device 30, and scanning device 40, the printing unit 11 further includes a cap 14, a moving device 15 (Figure 3), and a non-volatile storage unit 16 (Figure 3). The non-volatile storage unit 16 will be described later.

[0014] The print head 20 has multiple nozzles 21. The multiple nozzles 21 are arranged in rows in the front-to-back direction, and the rows of multiple nozzles 21 are arranged in the left-to-right direction. As shown in Figure 2, the nozzles 21 open onto the discharge surface 23, which is the lower surface of the print head 20. The print head 20 also has a drive element 22. The drive element 22 is a piezoelectric element and is provided corresponding to the nozzles 21, and applies pressure to the ink in the print head 20 to discharge ink from the nozzles 21.

[0015] As shown in FIG. 1, the conveying device 30 has, for example, two conveying rollers 31 and a conveying motor 32. The two conveying rollers 31 are arranged with the platen 12 sandwiched therebetween in the front-rear direction. The conveying roller 31 has a shaft extending in the left-right direction and is connected to the conveying motor 32. The conveying roller 31 rotates about the shaft by the drive of the conveying motor 32, and conveys the printing medium A in the front-rear direction on the platen 12.

[0016] The scanning device 40 has a carriage 41, two guide rails 42, a scanning motor 43, and an endless belt 44. The carriage 41 mounts the head 20 and is supported by the two guide rails 42 so as to be movable in the left-right direction. The two guide rails 42 extend in the left-right direction above the platen 12 so as to sandwich the head 20 therebetween in the front-rear direction. The endless belt 44 extends in the left-right direction, is attached to the carriage 41, and is also attached to the scanning motor 43 via a pulley 45. When the scanning motor 43 is driven, the endless belt 44 runs, and the carriage 41 reciprocates in the left-right direction along the guide rail 42. Thereby, the carriage 41 moves the head 20 in the left-right direction between the printing range and the maintenance range.

[0017] In the example of FIG. 1, the cap 14 is arranged in the maintenance range on the right side of the printing range within the movement range of the head 20 in the left-right direction by the scanning device 40. The cap 14 is made of an elastic material such as rubber and is a box-shaped container with an open upper side, and is a member capable of covering the discharge surface 23 of the head 20.

[0018] As shown in FIGS. 1 and 3, the moving device 15 has a moving motor 15a, and when the moving motor 15a is driven, the head 20 and the cap 14 are relatively moved. For example, the moving device 15 moves the cap 14 in the vertical direction with respect to the head 20 so that the cap 14 contacts or separates from the discharge surface 23 of the head 20. In addition, if the cap 14 contacts or separates from the discharge surface 23 of the head 20, the moving device 15 may move the head 20 in the vertical direction with respect to the cap 14.

[0019] The moving device 15 moves the cap 14 located below the ejection surface 23 upward to bring the cap 14 closer to the ejection surface 23. Then, when the upper edge surrounding the periphery of the upper opening of the cap 14 contacts the ejection surface 23, the moving device 15 stops the movement of the cap 14. By this capping operation, a capping state is achieved in which the ejection surface 23 is covered by the cap 14. In this capping state, the space between the ejection surface 23 and the inner surface of the cap 14 is blocked, and drying of the ink from the nozzle 21 opening to the ejection surface 23 is reduced.

[0020] On the other hand, the moving device 15 moves the cap 14 downward to separate it from the ejection surface 23 and stops the movement of the cap 14. By this uncapping operation, an uncapping state is achieved in which the ejection surface 23 is separated from the cap 14. In the uncapping state, the space between the ejection surface 23 and the inner surface of the cap 14 is opened, and the ejection surface 23 appears outside.

[0021] <Control Unit> The control unit 50 is, for example, a computer and includes an interface 51, an arithmetic unit 52, a storage unit 53, and a non-volatile storage unit 16. The interface 51 receives various data such as image data from external devices B such as a computer, a camera, a communication network, a recording medium, a display, and a printer. The image data is raster data or the like indicating an image to be printed on the printing medium A. Note that the control unit 50 may be constituted by a single device, or a plurality of devices may be distributed and configured such that they cooperate to perform the operation of the printing device 10.

[0022] The memory unit 53 is a memory accessible from the arithmetic unit 52 and includes RAM and ROM. The RAM temporarily stores various data such as image data and data converted by the arithmetic unit 52, and the stored data is erased when the power supply is cut off. The ROM stores programs for various data processing and predetermined data. The programs may be stored on an external storage medium different from the memory unit 53 that is accessible from the arithmetic unit 52, such as a CD-ROM.

[0023] The non-volatile storage unit 16 is a memory accessible by the arithmetic unit 52, and examples include flash memory. The non-volatile storage unit 16 is rewritable and retains stored data even without external power supply. The non-volatile storage unit 16 may be provided separately from the control unit 50. Alternatively, the non-volatile storage unit 16 may be included in the storage unit 53.

[0024] The arithmetic unit 52 includes, for example, at least one of the circuits of a processor such as a CPU and an integrated circuit such as an ASIC. The arithmetic unit 52 controls each part by executing a program and performs various operations such as processing operations. Details of the various operations will be described later.

[0025] Such a control unit 50 is connected to the drive element 22 via a head drive circuit 24. The control unit 50 outputs a control signal for the drive element 22 to the head drive circuit 24 based on image data, and the head drive circuit 24 generates a drive signal based on the control signal and outputs it to the drive element 22. The drive element 22 is driven in accordance with the drive signal, and ink is ejected from the nozzle 21.

[0026] Furthermore, the control unit 50 is connected to the transport motor 32 of the transport device 30 and controls the drive of the transport motor 32. This controls the transport of the printing medium A by the transport device 30. In addition, the control unit 50 is connected to the scanning motor 43 of the scanning device 40 and controls the drive of the scanning motor 43. This controls the movement of the head 20 by the scanning device 40. The control unit 50 is connected to the moving motor 15a of the moving device 15 and controls the drive of the moving motor 15a. This controls the movement of the cap 14.

[0027] <Power Control Circuit> As shown in Figure 4, the printing apparatus 10 has an AC / DC converter 60. The AC / DC converter 60 is connected to an external power source C, such as a commercial power supply, and is supplied with AC voltage power from the external power source C. The AC / DC converter 60 is also connected to a control unit 50, and when the external power source C is able to supply power, it converts the AC voltage power to, for example, 36V DC voltage power and supplies it to the control unit 50.

[0028] The control unit 50 includes a head control unit 50a, a transport control unit 50b, a scanning control unit 50c, and a movement control unit 50d. The head control unit 50a, transport control unit 50b, scanning control unit 50c, and movement control unit 50d are composed of a calculation unit 52 (Figure 3) and a storage unit 53 (Figure 3). The head control unit 50a is connected to the head 20 and controls the ejection of ink from the head 20. The transport control unit 50b is connected to the transport device 30 and controls the transport of the printing medium A by the transport device 30. The scanning control unit 50c is connected to the scanning device 40 and controls the movement of the head 20 by the scanning device 40. The movement control unit 50d is connected to the movement device 15 and controls the capping operation by the movement device 15.

[0029] When the external power supply C can supply power to the printing device 10, the control unit 50 is driven by the power from the external power supply C and supplies power to the printing unit 11. Furthermore, a voltage detection unit 67 is provided in the circuit connected to the AC / DC conversion unit 60. Based on the voltage detected by the voltage detection unit 67, the control unit 50 detects the cessation of power supply from the external power supply C via the AC / DC conversion unit 60, i.e., a power outage.

[0030] Furthermore, the AC / DC conversion unit 60 is connected to the charging voltage conversion unit 61 and converts AC voltage power to, for example, 36V DC voltage power and supplies it to the charging voltage conversion unit 61. The charging voltage conversion unit 61 is connected to the energy storage unit 62 and converts the voltage from, for example, 36V to 8V and supplies power to the energy storage unit 62. The energy storage unit 62 is a rechargeable and dischargeable electronic component, such as a capacitor and a secondary battery. The energy storage unit 62 is charged and stored from the external power supply C while the external power supply C is able to supply power. The energy storage unit 62 is connected to the control unit 50, and when the supply of power from the external power supply C to the printing device 10 stops, the energy storage unit 62 discharges the stored power and supplies power to the control unit 50.

[0031] Furthermore, a voltage detection unit 63 is connected to the energy storage unit 62. The voltage detection unit 63 detects the voltage in the electronic circuit connected to the energy storage unit 62 and outputs it to the control unit 50. As shown in the example in Figure 5, the power of the energy storage unit 62 has a predetermined relationship in which it increases as the voltage increases. This predetermined relationship is stored in advance in the memory unit 53 of the control unit 50. For example, if the energy storage unit 62 is a capacitor, the power U = 1 / 2 × C × V 2 This is expressed by the following equation: C is capacitance (F) and V is voltage (V). As a result, the control unit 50 can acquire the power stored in the energy storage unit 62 based on the voltage detected by the voltage detection unit 63.

[0032] As shown in Figure 4, the energy storage unit 62 is connected to a plurality of voltage conversion units 65 via a switching unit 64. The switching unit 64 switches the input destination of the power from the energy storage unit 62 to at least one of the plurality of voltage conversion units 65. The switching unit 64 is connected to a control unit 50, and the switching of the voltage conversion units 65 is controlled by the control unit 50.

[0033] The switching unit 64 has, for example, three switches (first switch 64a, second switch 64b, and third switch 64c). The first switch 64a, second switch 64b, and third switch 64c are connected in parallel to the energy storage unit 62. The multiple voltage conversion units 65 have, for example, a first voltage conversion unit 65a, a second voltage conversion unit 65b, and a third voltage conversion unit 65c. The first switch 64a is disconnectably connected to the energy storage unit 62 and the first voltage conversion unit 65a. The second switch 64b is disconnectably connected to the energy storage unit 62 and the second voltage conversion unit 65b. The third switch 64c is disconnectably connected to the energy storage unit 62 and the third voltage conversion unit 65c.

[0034] Multiple voltage conversion units 65 are provided in parallel between the energy storage unit 62 and the printing unit 11. They convert the voltage of the power input from the energy storage unit 62 into multiple voltages that are different from each other, according to the operating voltages of multiple processing operations, and output them to the printing unit 11.

[0035] The first voltage conversion unit 65a converts the voltage of the input power to a first voltage according to the operating voltage of the printing operation. For example, the first voltage conversion unit 65a is connected to the head control unit 50a, the transport control unit 50b, and the scanning control unit 50c of the control unit 50. The first voltage conversion unit 65a converts the voltage of the input power, which is 5V or more and 8V or less, to a first voltage of 36V according to the operating voltage of the printing operation by the head 20, etc. Then, the first voltage conversion unit 65a supplies the converted power to the head 20 via the head control unit 50a, to the transport device 30 via the transport control unit 50b, and to the scanning device 40 via the scanning control unit 50c. As a result, the head 20, transport device 30, and scanning device 40 of the printing unit 11 can perform printing operations using power from the energy storage unit 62 in the event of a power outage of the external power supply C.

[0036] The second voltage conversion unit 65b converts the voltage of the input power to a second voltage that is lower than the first voltage. For example, the second voltage conversion unit 65b is connected to the moving device 15 of the printing unit 11 via the moving control unit 50d of the control unit 50. It converts the voltage of the input power, which is 3V or more and 8V or less, to a second voltage, for example 24V, according to the operating voltage of the capping operation by the moving device 15, and supplies the power with the converted voltage to the moving device 15 via the moving control unit 50d. As a result, the moving device 15 can perform the capping operation using power from the energy storage unit 62 in the event of a power outage of the external power supply C.

[0037] The third voltage conversion unit 65c converts the voltage of the input power to a third voltage that is lower than the first voltage. For example, the third voltage conversion unit 65c is connected to the non-volatile storage unit 16 of the printing unit 11, and converts the voltage of the input power, which is 1V or more and 8V or less, to a third voltage, for example 5V, according to the operating voltage of the storage operation by the non-volatile storage unit 16, and supplies the power with the converted voltage to the non-volatile storage unit 16. As a result, the non-volatile storage unit 16 can perform storage operations using power from the energy storage unit 62 in the event of a power outage of the external power supply C.

[0038] <Processing Actions> The processing operation includes a printing operation and a backup operation. The printing operation is the operation of printing an image onto the printing medium A by driving the drive element 22, the transport device 30, and the scanning device 40 with a first voltage based on image data. In this printing operation, the control unit 50 acquires image data and performs a pass and transport based on the image data. In the pass, the control unit 50 moves the head 20 to the right or left while ejecting ink from the head 20 onto the printing medium A. In the transport, the control unit 50 transports the printing medium A forward. The printing device 10 then proceeds with the printing operation, alternating between the pass and transport, and printing an image onto the printing medium A with ink.

[0039] The backup operation includes a capping operation and a memory operation. The capping operation is performed with a second voltage lower than the first voltage and moves the cap 14 so as to cover the ejection surface 23. In this capping operation, the control unit 50 moves the cap 14 closer to the ejection surface 23 of the head 20 and brings the cap 14 into contact with the ejection surface 23. As a result, the ejection surface 23 is covered by the cap 14, which suppresses the drying of ink at the nozzle 21 that opens into the ejection surface 23. This suppresses the thickening of the ink due to drying, and thus suppresses ink ejection failure caused by thickening.

[0040] The memory operation operates at a third voltage lower than the second voltage and stores log data in the non-volatile memory unit 16. That is, each time the head 20, moving device 15, transport device 30, scanning device 40, and control unit 50 operate, the control unit 50 stores the details of that operation as log data in the memory unit 53. In addition, as the printing operation progresses, the control unit 50 sequentially outputs control signals for the drive element 22 based on the image data to the head drive circuit 24, and stores the unprinted image data that remains without being output as log data in the memory unit 53.

[0041] If a power outage occurs in the external power supply C, the control unit 50 stores at least the log data related to incomplete operations in the non-volatile storage unit 16. For example, the control unit 50 has performed an uncapping operation to separate the cap 14 from the dispensing surface 23, but has not performed a capping operation to cover the dispensing surface 23 with the cap 14. In this case, the control unit 50 considers the capping operation as an incomplete operation and stores the log data of the uncapping operation as log data related to incomplete operations in the non-volatile storage unit 16. From this log data, it can be seen that the capping operation is incomplete and the dispensing surface 23 is in an uncapping state.

[0042] Furthermore, the control unit 50 has started outputting a control signal for the drive element 22 to the head drive circuit 24 based on the image data and started printing, but has not yet stopped outputting the control signal based on this image data. In this case, the control unit 50 considers the printing operation as an incomplete operation and stores the log data for the start of printing and the unprinted image data as log data related to the incomplete operation in the non-volatile storage unit 16. This log data allows the system to determine that the printing operation has started but not finished, that is, that the printing operation is incomplete and how far the printing operation has progressed.

[0043] <Control method for printing devices> The printing device 10 is controlled by the control unit 50 according to the flowchart shown as an example in the control method of Figure 6. First, the control unit 50 detects whether or not a power outage has occurred with respect to the external power supply C (step S1). If the control unit 50 detects that a power outage has occurred (step S1: YES), it switches the input destination of the power from the energy storage unit 62 to at least one of the multiple voltage conversion units 65 according to the operating voltage of the incomplete operation among the multiple processing operations, and executes the incomplete operation.

[0044] Specifically, the control unit 50 acquires the voltage of the energy storage unit 62 detected by the voltage detection unit 63 and acquires the power of the energy storage unit 62 corresponding to the voltage based on a predetermined correspondence relationship shown in the example of Figure 5 (step S2). The control unit 50 then determines whether or not printing is in progress based on the log data (step S3). If the log data for the end of printing is not stored in the storage unit 53 after the log data for the start of printing, the control unit 50 determines that printing is in progress (step S3: YES). The control unit 50 then determines whether or not the power of the energy storage unit 62 acquired in step S2 is equal to or greater than a first predetermined power (step S4).

[0045] Thus, if a power outage occurs while the printing operation is incomplete (step S3: YES), and the power of the energy storage unit 62 is equal to or greater than the first predetermined power (step S4: YES), the control unit 50 causes the printing operation, capping operation, and storage operation to be executed as incomplete operations (steps S5 to S7). The first predetermined power is power sufficient to perform at least the printing operation, capping operation, and storage operation, and is stored in advance in the storage unit 53.

[0046] In step S5, the control unit 50 switches the input destination of power from the energy storage unit 62 to the first voltage conversion unit 65a among the multiple voltage conversion units 65, according to the operating voltage of the printing operation, and executes the printing operation. The first voltage conversion unit 65a converts the voltage of the power from the energy storage unit 62 to a first voltage, and the head 20, transport device 30, and scanning device 40 are driven by the power of this first voltage, and the printing operation is executed. This printing operation can reduce the decrease in printing efficiency caused by interruptions in printing operation due to power outages.

[0047] Furthermore, in step S6, the control unit 50 switches the input destination of the power from the energy storage unit 62 to the second voltage conversion unit 65b among the multiple voltage conversion units 65, according to the operating voltage of the capping operation, and executes the capping operation. The second voltage conversion unit 65b converts the voltage of the power from the energy storage unit 62 to a second voltage, and the moving device 15 is driven by the power of this second voltage, causing the cap 14 to move and cover the discharge surface 23. This capping operation reduces the drying of ink at the nozzle 21 that opens to the discharge surface 23, thereby reducing the decrease in printing efficiency due to poor ink discharge caused by drying.

[0048] Furthermore, in step S7, the control unit 50 switches the power input destination from the energy storage unit 62 to the third voltage conversion unit 65c among the multiple voltage conversion units 65, according to the operating voltage of the memory operation, and executes the memory operation. The third voltage conversion unit 65c converts the voltage of the power from the energy storage unit 62 to a third voltage, and log data related to incomplete operations is stored in the non-volatile storage unit 16 using this third voltage power. At this time, if the printing operation and capping operation are completed, the log data of the completion of printing and the log data of the capping operation are stored in the non-volatile storage unit 16 along with the log data related to incomplete operations. This memory operation makes it possible to know when there are no incomplete operations when restarting after a power outage, and reduces the decrease in printing efficiency caused by the power outage.

[0049] Furthermore, in step S4 during the printing operation, if the power of the energy storage unit 62 acquired in step S2 is less than the first predetermined power (step S4: NO), the control unit 50 determines whether the power of the energy storage unit 62 is equal to or greater than the second predetermined power (step S8). The second predetermined power is less than the first predetermined power and is sufficient to perform at least the capping operation and the storage operation, and is stored in the storage unit 53 in advance. Here, if the power of the energy storage unit 62 is less than the first predetermined power and equal to or greater than the second predetermined power (step S8: YES), the control unit 50 performs the capping operation and the storage operation without performing the printing operation among the incomplete operations (steps S6, S7). On the other hand, if the power of the energy storage unit 62 is less than the second predetermined power during the printing operation (step S8: YES), the control unit 50 interrupts the printing operation among the incomplete operations and performs the storage operation without performing the printing operation and the capping operation (step S7). This allows the power storage unit 62 to be used to its maximum extent to perform incomplete operations, thereby reducing the decrease in printing efficiency caused by power outages.

[0050] Next, if the printing operation is complete (step S3: NO), the control unit 50 determines whether or not it is in an uncapping state (step S9). Here, if no log data of the capping operation is stored in the storage unit 53 after the uncapping operation, the control unit 50 determines that it is in an uncapping state (step S9: YES). Then, the control unit 50 determines whether or not the power of the energy storage unit 62 acquired in step S2 is equal to or greater than the second power level (step S8).

[0051] Thus, if a power outage occurs while the printing operation is complete but the capping operation is incomplete (step S9: YES), and the power of the energy storage unit 62 acquired in step S2 is equal to or greater than the second predetermined power (step S8: YES), the control unit 50 causes the capping operation and the storage operation to be executed as incomplete operations (steps S6, S7). By executing incomplete operations in this way during a power outage, the decrease in printing efficiency caused by the power outage can be reduced.

[0052] In contrast, in the uncapping state (step S9: YES), if the power of the energy storage unit 62 acquired in step S2 is less than the second predetermined power (step S8: NO), the capping operation among the incomplete operations is not performed, and the storage operation is performed (step S7). This makes it possible to reduce the decrease in printing efficiency caused by power outages by using the power of the energy storage unit 62 to the maximum extent for backup operations.

[0053] Furthermore, if a power outage occurs while the printing and capping operations are completed (step S9: NO), the control unit 50 causes the storage operation to be executed as an incomplete operation (step S7). As a result, the log data for the completion of printing and the log data for the capping operation are stored in the non-volatile storage unit 16 along with the log data for the incomplete operation. Therefore, processing can be performed based on this log data when the system is restarted after a power outage, thereby reducing the decrease in printing efficiency caused by the power outage.

[0054] In this way, when a power outage occurs, the control unit 50 switches the input destination of power from the energy storage unit 62 to at least one of the multiple voltage conversion units 65 according to the operating voltage of the incomplete operation among the multiple processing operations, and executes the incomplete operation. This allows the voltage of the power from the energy storage unit 62 to be appropriately converted according to the incomplete operation, and the occurrence of energy loss due to multi-stage voltage conversion can be suppressed. Therefore, by executing as many incomplete operations as possible, the decrease in printing efficiency due to power outages can be reduced.

[0055] <Example 1> In the printing apparatus 10 according to Modification 1, as shown in Figures 1 and 3, the printing unit 11 in the above embodiment includes a tank 13 for storing ink supplied to the nozzle 21 and a stirring device 17 for stirring the ink stored in the tank 13. The backup operation has a stirring operation that operates at a fourth voltage that is less than the first voltage and greater than the second voltage, and stirs the ink stored in the tank 13.

[0056] As shown in Figure 1, the agitator 17 includes, for example, a rotating shaft 17a, a propeller 17b, and an agitator motor 17c. The propeller 17b is attached to the rotating shaft 17a and extends radially from the rotating shaft 17a. The agitator motor 17c is connected to the rotating shaft 17a and rotates the rotating shaft 17a. As a result, the propeller 17b rotates around the rotating shaft 17a inside the tank 13. Therefore, the ink inside the tank 13 is agitated by the propeller 17b, which reduces sedimentation and thickening of the ink's contents.

[0057] As shown in Figure 7, the switching unit 64 includes, for example, a first switch 64a, a second switch 64b, and a third switch 64c, as well as a fourth switch 64d. The first switch 64a, the second switch 64b, the third switch 64c, and the fourth switch 64d are connected in parallel to the energy storage unit 62. In addition, the multiple voltage conversion units 65 include, for example, a first voltage conversion unit 65a, a second voltage conversion unit 65b, and a third voltage conversion unit 65c, as well as a fourth voltage conversion unit 65d. The fourth switch 64d is disconnectably connected to the energy storage unit 62 and the fourth voltage conversion unit 65d.

[0058] The fourth voltage conversion unit 65d converts the voltage of the input power to a fourth voltage according to the operating voltage of the stirring operation. For example, the fourth voltage conversion unit 65d is connected to the stirring device 17 via the stirring control unit 50e of the control unit 50. The fourth voltage conversion unit 65d converts the voltage of the input power, which is 3V or more and 8V or less, to a fourth voltage of 24V according to the operating voltage of the stirring operation by the stirring device 17, and supplies the converted power to the stirring device 17 via the stirring control unit 50e. The stirring control unit 50e is composed of the calculation unit 52 (Figure 3) and the storage unit 53 (Figure 3) of the control unit 50, and controls the drive of the stirring motor 17c (Figure 3) of the stirring device 17. As a result, the stirring device 17 can perform stirring operations using power from the power storage unit 62 in the event of a power outage.

[0059] Such a printing apparatus 10 is controlled by a control unit 50 according to a flowchart, for example, shown in the control method of Figure 8. In this flowchart of Figure 8, steps S10 and S11 are executed after the process of step S7 in Figure 6. Specifically, after the memory operation is performed (step S7), if the printing operation performed in S5, the capping operation performed in S6, and the memory operation performed in S7 have been completed (step S10: YES), the control unit 50 executes a stirring operation (step S11). Here, if a power outage occurs while the printing operation, capping operation and memory operation are completed, the control unit 50 switches the input destination of the power from the energy storage unit 62 to the fourth voltage conversion unit 65d, which converts to the fourth voltage among the multiple voltage conversion units 65, and executes the stirring operation.

[0060] As a result, the stirring device 17 performs a stirring operation due to the fourth voltage, stirring the ink in the tank 13, suppressing sedimentation and thickening of ink contents, reducing ejection failures when restarting after a power outage, and thus reducing the decrease in printing efficiency caused by ejection failures. In addition, by continuing the stirring operation until the remaining power in the energy storage unit 62 is depleted due to the execution of incomplete operations, the power of the energy storage unit 62 can be used effectively, and the decrease in printing efficiency caused by power outages can be reduced.

[0061] <Modification 2> In the printing apparatus 10 according to Modification 2, as in the above embodiment and Modification 1, the control unit 50 determines the charging state of the energy storage unit 62 based on the voltage detected by the voltage detection unit 63. Specifically, the control unit 50 acquires the voltage detected by the voltage detection unit 63 when the energy storage unit 62 is being charged, and monitors the change in the voltage of the energy storage unit 62 over time, as shown in Figure 9. When the energy storage unit 62 is being charged from an external power supply C, the voltage increases over time, and the rate of change of the voltage per unit time is greater than or equal to a predetermined rate. This rate of change decreases as the amount of power stored in the energy storage unit 62 increases, and continues to decrease over time. When the rate of change falls below the predetermined rate, the energy storage unit 62 is in a fully charged state, indicating that charging is complete.

[0062] The voltage of the fully charged energy storage unit 62 decreases over time due to deterioration. For example, in graph Va showing the change in voltage over time during charging at time Ta, at time T0 the rate of change of the voltage falls below a predetermined rate, and the energy storage unit 62 becomes fully charged, at which point the voltage is V0. In graph Vb showing the change in voltage over time during charging at time Tb after time Ta, at time T1 the rate of change of the voltage falls below a predetermined rate, and the energy storage unit 62 becomes fully charged, at which point the voltage is V1. Voltage V1 is smaller than voltage V0 and lower than the predetermined voltage.

[0063] Therefore, the control unit 50 acquires the voltage of the energy storage unit 62 detected by the voltage detection unit 63 and calculates its rate of change. In graph Va, the control unit 50 determines that the energy storage unit 62 is charging before full charge because the voltage reaches V1 at time T2 and its rate of change is greater than or equal to a predetermined rate. On the other hand, in graph Vb, the control unit 50 determines that the energy storage unit 62 is fully charged because the voltage reaches V1 at time T1 and its rate of change is less than a predetermined rate. For example, if the printing device 10 is equipped with an output unit 72 (Figure 3) such as a display device, the control unit 50 outputs the determined charging state to the output unit 72. This allows the user to understand the charging state of the energy storage unit 62.

[0064] Furthermore, the control unit 50 acquires the voltage at full charge when the rate of change is less than a predetermined value. In graph Va, the control unit 50 determines that the energy storage unit 62 is usable because the voltage V0 is above the predetermined voltage. On the other hand, in graph Vb, the control unit 50 determines that the energy storage unit 62 is degraded because the voltage V1 is below the predetermined voltage. If degradation is determined, the control unit 50 outputs a warning to the output unit 72, such as the need to replace the energy storage unit 62. This allows the user to reduce the decrease in printing efficiency caused by the degradation of the energy storage unit 62 by replacing the energy storage unit 62 based on the warning.

[0065] <Other variations> In the printing apparatus 10 according to the above embodiment and all its modifications, the processing operation included a capping operation and a storage operation. However, the processing operation may include other operations. For example, the processing operation may include at least one of the following: a wiping operation, a circulation operation, a flushing operation, and a purging operation. For example, if a power outage occurs while the printing operation is incomplete, the printing operation, wiping operation, circulation operation, capping operation, storage operation, and agitation operation may be executed in this order. Also, if a power outage occurs while the printing operation is complete but the capping operation is incomplete, the flushing operation, purging operation, wiping operation, circulation operation, capping operation, storage operation, and agitation operation may be executed in this order.

[0066] When the processing operation involves a wiping operation, the printing apparatus 10 includes a wiper 18 (Figure 1) and a wiping device 19 (Figure 3) as the printing unit 11. The wiper 18 is located within the maintenance area and is made of an elastic material such as rubber, and has a flat plate shape. The wiping device 19 has a wiping motor 19a and is connected to the second voltage conversion unit 65b. The wiping device 19 is controlled by the control unit 50, and the wiping motor 19a drives the discharge surface 23 and the wiper 18 to move relative to each other. For example, if the wiper 18 extends longer than the discharge surface 23 in the left-right direction, the wiping device 19 moves the wiper 18 in the front-back direction while keeping it in contact with the discharge surface 23. Also, if the wiper 18 extends longer than the discharge surface 23 in the front-back direction, the wiping device 19 moves the wiper 18 in the left-right direction while keeping it in contact with the discharge surface 23.

[0067] In this control method for the printing apparatus 10, for example, in step S6 of Figure 6, if a power outage occurs while the capping operation is incomplete, the control unit 50 switches the input destination of the power from the energy storage unit 62 to the second voltage conversion unit 65b among the multiple voltage conversion units 65, according to the operating voltage of the wiping operation, before the capping operation, and executes the wiping operation. The power from the energy storage unit 62 is converted to a second voltage by this second voltage conversion unit 65b, and the wiping device 19 is driven by the power of this second voltage, causing the wiper 18 to move while in contact with the ejection surface 23. As a result, the ink remaining on the ejection surface 23 is removed by the wiper 18, and the deterioration of image quality caused by the remaining ink can be reduced.

[0068] Furthermore, when the processing operation involves a circulating operation, the printing apparatus 10 is equipped with a sub-tank 25 and a pressure pump 26 as a printing unit 11, as shown in Figure 2. The head 20 has a nozzle 21, individual flow paths 27, a supply manifold 28, and a return manifold 29. Each of the supply manifold 28 and the return manifold 29 is connected to a plurality of individual flow paths 27, and the individual flow paths 27 are connected to the nozzle 21. The supply manifold 28 extends long in the front-to-back direction, and a supply pipe 28a is connected to one end in the longitudinal direction. The return manifold 29 extends long in the front-to-back direction, and a return pipe 29a is connected to one end in the longitudinal direction. This supply pipe 28a and return pipe 29a are connected to the sub-tank 25. The sub-tank 25, supply pipe 28a, supply manifold 28, individual flow paths 27, return manifold 29, and return pipe 29a are connected in this order, forming a circulating path. Furthermore, the sub-tank 25 is connected to the tank 13 (Figure 1), and ink is supplied from the tank 13. A pressure pump 26 is provided on the supply pipe 28a. The pressure pump 26 is connected to the second voltage conversion unit 65b, and its drive is controlled by the control unit 50.

[0069] In this control method for the printing apparatus 10, for example, in step S6 of Figure 6, if a power outage occurs while the capping operation is incomplete, the control unit 50 switches the input destination of power from the energy storage unit 62 to the second voltage conversion unit 65b among the multiple voltage conversion units 65, according to the operating voltage of the circulation operation, before the capping operation, and executes the circulation operation. The second voltage conversion unit 65b converts the voltage of the power from the energy storage unit 62 to a second voltage, and the pressurizing pump 26 is driven by the power of this second voltage. By driving this pressurizing pump 26 for a predetermined time, the ink in the head 20 circulates through the circulation path. As a result, the settling of solid matter in the ink and the thickening of the ink are suppressed, and the deterioration of image quality can be reduced.

[0070] Furthermore, if the processing operation involves a flushing operation, the printing device 10 is equipped with a receiving section 70 as the printing section 11, as shown in Figure 1. The receiving section 70 is located within the maintenance area of ​​the printing device 10 and is, for example, a container with an open top.

[0071] In this control method for the printing apparatus 10, for example, in step S6 of Figure 6, if a power outage occurs when the printing operation is complete but the capping operation is not yet complete, the control unit 50 switches the input destination of the power from the energy storage unit 62 to the first voltage conversion unit 65a among the multiple voltage conversion units 65, according to the operating voltage of the flashing operation, and executes the flashing operation before the capping operation. The first voltage conversion unit 65a converts the voltage of the power from the energy storage unit 62 to a first voltage, and the carriage 41 and the drive element 22 are driven by the power of this first voltage. As a result, the head 20 is moved by the carriage 41 so that the ejection surface 23 faces the upper opening of the receiving unit 70, and ink is ejected from the nozzle 21 to the receiving unit 70 by the drive element 22. As a result, the ink in the nozzle 21 is ejected, and the viscosity of the nozzle 21 is suppressed, thereby reducing the deterioration of image quality caused by ink viscosity.

[0072] Furthermore, if the processing operation includes a purging operation, the printing device 10 is equipped with a suction pump 71 as a printing unit 11, as shown in Figure 1. The suction pump 71 is connected to the inside of the cap 14 by a suction tube 71a and is controlled by the control unit 50. The suction pump 71 is connected to the second voltage conversion unit 65b, and its drive is controlled by the control unit 50. In the following, a suction purge using the suction pump 71 will be described as the purging operation, but the purging operation may also be a pressurized purge using a pressurizing pump 26 (Figure 2), etc.

[0073] In this control method for the printing apparatus 10, in step S6 of Figure 6, if a power outage occurs while the printing operation is complete but the capping operation is not yet complete, the control unit 50 switches the input destination of the power from the energy storage unit 62 to the second voltage conversion unit 65b among the multiple voltage conversion units 65, according to the operating voltage of the purge operation, and executes the purge operation before the capping operation. The power from the energy storage unit 62 is converted to a second voltage by this second voltage conversion unit 65b, and the moving device 15 and the suction pump 71 are driven by this second voltage, and with the cap 14 covering the discharge surface 23, the space surrounded by the cap 14 and the discharge surface 23 is sucked by the suction pump 71. As a result, the ink in the nozzle 21 is discharged and the viscosity of the nozzle 21 is suppressed, thereby reducing the deterioration of image quality caused by ink viscosity.

[0074] In the above embodiments and modifications, the head 20 employs a piezoelectric method (piezoelectric method) for the drive element 22, but is not limited to this method. For example, the head 20 may employ a thermal method using a heating element for the drive element 22, or an electrostatic method using a conductive diaphragm and electrodes for the drive element 22.

[0075] Furthermore, the above embodiments and modifications may be combined with each other, provided that they do not exclude one another. Also, many improvements and other embodiments of the present invention will be apparent to those skilled in the art from the above description. Therefore, the above description should be interpreted as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode of carrying out the invention. The details of its structure and / or function can be substantially modified without departing from the spirit of the invention. [Industrial applicability]

[0076] The printing apparatus of the present invention is useful as a printing apparatus that can reduce the decrease in printing efficiency due to power outages. [Explanation of symbols]

[0077] 10:Printing device 11:Printing Department 13: Tank 14: Cap 15: Mobile device 16: Non-volatile memory unit 17: Stirring device 20: Head 21: Nozzle 23:Discharge surface 50: Control Unit 53: Storage section 62: Energy Storage Unit 63: Voltage detection unit 64: Switching section 65: Voltage conversion section 65a: First voltage conversion unit 65b: Second voltage conversion section 65c: Third voltage conversion section 65d: Fourth voltage conversion section

Claims

1. A printing unit having a head that ejects ink from a nozzle, and performing multiple processing operations that include a printing operation related to printing on a printing medium with the ejected ink and a backup operation related to the backup of the printing operation, and which have different operating voltages from each other, A power storage unit capable of storing power from an external power source, Multiple voltage conversion units are provided in parallel between the power storage unit and the printing unit, and each converts the voltage of the power input from the power storage unit into a plurality of voltages that are different from each other according to the operating voltage of a plurality of processing operations, and outputs them to the printing unit. A switching unit that switches the input destination of power from the energy storage unit to at least one of the multiple voltage conversion units, It comprises a control unit and, The control unit detects whether or not a power outage has occurred with respect to the external power supply, and if a power outage has occurred, it switches the power input destination from the energy storage unit to at least one of the multiple voltage conversion units according to the operating voltage of the incomplete operation among the multiple processing operations, and executes the incomplete operation. Printing device.

2. Multiple of the aforementioned voltage conversion units are A first voltage conversion unit converts the input power voltage into a first voltage according to the operating voltage of the printing operation, It includes a second voltage conversion unit that converts the voltage of the input power to a second voltage that is smaller than the first voltage, If a power outage occurs while the printing operation is incomplete, the control unit switches the power input destination from the energy storage unit to the first voltage conversion unit among the multiple voltage conversion units, according to the operating voltage of the printing operation, and then executes the printing operation. The printing apparatus according to claim 1.

3. The aforementioned printing unit is The head includes a cap capable of covering the discharge surface through which the nozzle opens, It has a moving device that moves the head and the cap relative to each other, The backup operation includes a capping operation that moves the head and the cap relative to each other so as to cover the discharge surface. Multiple of the aforementioned voltage conversion units are A first voltage conversion unit that converts the voltage of the input power into a first voltage, It includes a second voltage conversion unit that converts the voltage of the input power to a second voltage that is smaller than the first voltage and corresponds to the operating voltage of the capping operation, If a power outage occurs while the capping operation is incomplete, the control unit, in accordance with the operating voltage of the capping operation, switches the input destination of the power from the energy storage unit to the second voltage conversion unit among the plurality of voltage conversion units, thereby executing the capping operation. The printing apparatus according to claim 1.

4. The printing unit has a non-volatile storage unit, The backup operation includes a storage operation that stores log data relating to the incomplete operation in the non-volatile storage unit. Multiple of the aforementioned voltage conversion units are A first voltage conversion unit that converts the voltage of the input power into a first voltage, It includes a third voltage conversion unit that converts the voltage of the input power to a third voltage that is less than the first voltage and corresponds to the operating voltage of the memory operation, When a power outage occurs, the control unit switches the power input destination from the energy storage unit to the third voltage conversion unit among the plurality of voltage conversion units, according to the operating voltage of the memory operation, and executes the memory operation. The printing apparatus according to claim 1.

5. The aforementioned printing unit is The head includes a cap capable of covering the discharge surface through which the nozzle opens, A moving device for moving the head and the cap relative to each other, A non-volatile storage unit that stores log data related to the aforementioned incomplete operation, A tank for storing the ink supplied to the nozzle, The system includes a stirring device for stirring the ink stored in the tank, The aforementioned printing operation operates at the first voltage, The aforementioned backup operation is, A capping operation is performed using a second voltage smaller than the first voltage to move the head and the cap relative to each other so as to cover the discharge surface. A storage operation which operates at a third voltage lower than the second voltage and stores the log data in the non-volatile storage unit, It has a stirring operation that operates at a fourth voltage that is less than the first voltage and greater than the second voltage, and stirs the ink stored in the tank, If a power outage occurs while the printing operation is incomplete, the control unit switches the power input destination from the energy storage unit to the first voltage conversion unit, which converts the power to the first voltage among the plurality of voltage conversion units, and then executes the printing operation. The printing apparatus according to claim 1.

6. If a power outage occurs while the printing operation is complete but the capping operation is not yet complete, the control unit switches the power input destination from the energy storage unit to the second voltage conversion unit, which converts the power to the second voltage among the multiple voltage conversion units, and then performs the capping operation. The printing apparatus according to claim 5.

7. If a power outage occurs while the printing and capping operations are completed, the control unit switches the power input destination from the energy storage unit to the third voltage conversion unit, which converts the power to the third voltage among the plurality of voltage conversion units, and then executes the storage operation. The printing apparatus according to claim 5.

8. If a power outage occurs while the printing operation, the capping operation, and the storage operation are completed, the control unit switches the power input destination from the power storage unit to the fourth voltage conversion unit, which converts the power to the fourth voltage among the plurality of voltage conversion units, and then executes the stirring operation. The printing apparatus according to claim 5.

9. The system includes a voltage detection unit that detects the voltage of the energy storage unit, The aforementioned printing unit is The head includes a cap capable of covering the discharge surface through which the nozzle opens, A moving device for moving the head and the cap relative to each other, It has a non-volatile storage unit that stores log data related to the incomplete operation, The aforementioned backup operation is, A capping operation in which the head and the cap are moved relative to each other so as to cover the discharge surface, The system includes a storage operation that stores log data relating to the incomplete operation in the non-volatile storage unit. If a power outage occurs while the printing operation is incomplete, and the power of the energy storage unit based on the voltage detected by the voltage detection unit is equal to or greater than a first predetermined power, the control unit will execute the printing operation, the capping operation, and the storage operation. The printing apparatus according to claim 1.

10. If a power outage occurs while the printing operation is incomplete, and the power of the energy storage unit is less than a first predetermined power and greater than or equal to a second predetermined power which is less than the first predetermined power, the control unit will not perform the printing operation, but will instead perform the capping operation and the storage operation. The printing apparatus according to claim 9.

11. If a power outage occurs while the printing operation is incomplete, and the power of the energy storage unit is less than the second predetermined power which is less than the first predetermined power, the control unit will not perform the printing operation, and will not perform the printing operation or the capping operation, but will instead perform the storage operation. The printing apparatus according to claim 9.

12. If a power outage occurs while the printing operation is completed but the capping operation is not yet completed, and the power of the energy storage unit is greater than or equal to a second predetermined power which is less than the first predetermined power, the control unit will perform the capping operation and the storage operation. The printing apparatus according to claim 9.

13. If a power outage occurs while the printing operation is complete but the capping operation is not yet complete, and the power of the energy storage unit is less than the second predetermined power which is less than the first predetermined power, the control unit will execute the storage operation without executing the capping operation. The printing apparatus according to claim 9.

14. The system includes a voltage detection unit that detects the voltage of the power stored in the energy storage unit, The control unit determines the charging state of the energy storage unit based on the voltage detected by the voltage detection unit. The printing apparatus according to claim 1.

Images