JP6064797B2 - Liquid supply apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a liquid supply apparatus and an image forming apparatus.

  In Patent Document 1, the flow rate on the sub-pump side is controlled so that the pressure of the liquid in the flow path becomes a predetermined pressure by a main pump that sends liquid at a constant flow rate and a sub-pump provided in parallel with the main pump. The structure to be disclosed is disclosed.

  In Patent Document 2, P0 ≦ P1 <P2 ≦ Pm, where Pm is the maximum meniscus holding pressure, P0 is the minimum meniscus holding pressure, P1 is the minimum pressure in the path of the fluctuating pressure, and P2 is the maximum pressure in the path. As a relationship, a configuration is disclosed in which the meniscus holding minimum pressure is controlled to P0, and the minimum pressure in the path of the fluctuating pressure is controlled to P1.

JP 2010-82811 A JP 2006-224435 A

  An object of the present invention is to be able to control periodic fluctuations in the supply path.

  According to the first aspect of the present invention, there are provided a supply path for supplying a liquid to a discharge section having a discharge port, and a plurality of supplies that are provided in parallel to the supply path and supply the liquid to the discharge section via the supply path And detecting means for detecting periodic fluctuations in the supply path due to driving of the supply section, and for each of the plurality of supply sections, detected by the detection means when the supply section is driven A periodic variation is acquired, and based on the phase of the periodic variation acquired for each of the plurality of supply units, the phase difference of the periodic variation when the plurality of supply units is driven is And a control unit that controls driving of the plurality of supply units so as to obtain a predetermined phase difference.

  According to a second aspect of the present invention, the detection means detects a change in pressure in the supply path as a periodic fluctuation in the supply path, and the control means A change in pressure detected by the detection unit when the supply unit is driven is acquired, and the plurality of supply units are driven based on the phase of the change in pressure acquired for each of the plurality of supply units. The liquid supply apparatus according to claim 1, wherein the driving of the plurality of supply units is controlled such that a phase difference of the pressure change at the time becomes a predetermined phase difference.

  According to a third aspect of the present invention, the plurality of supply sections are provided in parallel to the supply path, and are driven to rotate to supply liquid to the discharge section via the supply path. As a periodic variation in the supply path, for each of the plurality of supply units, detecting a change in the rotation angle of the supply unit, the correspondence of which is obtained in advance with the periodic variation, the control means, For each of the plurality of supply units, the change in the rotation angle detected by the detection unit when the supply unit is driven is acquired, and the phase of the change in the rotation angle acquired for each of the plurality of supply units 2. The driving of the plurality of supply units is controlled based on the control unit so that the phase difference of the change in the rotation angle when the plurality of supply units is driven becomes a predetermined phase difference. A liquid supply device;

  According to a fourth aspect of the present invention, the plurality of supply units are driven at different driving speeds to supply liquid to the discharge unit via the supply path, and the control unit is configured to control the plurality of supply units. Based on the phase of the periodic fluctuation acquired for each and the ratio of the periodic fluctuation periods, each of the periodic fluctuation periods when the plurality of supply units are driven corresponds. In addition, the plurality of periodic fluctuations when the plurality of supply units are driven so that each of the periodic fluctuation periods corresponds to the predetermined phase difference. It is a liquid supply apparatus of any one of Claims 1-3 which control the drive of a supply part.

  According to a fifth aspect of the present invention, there are provided a plurality of drive units for driving each of the plurality of supply units, and a plurality of drive units for driving each of the plurality of drive units. And a plurality of switching units for switching whether or not to connect between the control unit and the control unit, and the control unit is connected via the switching unit among the plurality of drive units The switching unit for each of the plurality of supply units so as to control the drive unit to be driven and the phase difference when the plurality of supply units are driven becomes a predetermined phase difference. It is a liquid supply apparatus of any one of Claims 1-4 which control the connection timing between the said drive parts by.

  According to a sixth aspect of the present invention, the control means includes the plurality of supply units so that the phase difference when the plurality of supply units are driven becomes a value corresponding to half of the period of the periodic variation. It is a liquid supply apparatus of any one of Claims 1-5 which control the drive of these.

  According to a seventh aspect of the invention, the control means controls the driving of the plurality of supply units so that the phase difference when the plurality of supply units is driven becomes a value corresponding to zero. It is a liquid supply apparatus of any one of -5.

  The invention according to claim 8 is any one of claims 1 to 7, wherein a transport unit that transports the recording medium, a discharge unit that discharges liquid to the recording medium transported by the transport unit, and a liquid is supplied to the discharge unit An image forming apparatus comprising the liquid supply device according to the item.

  According to the configuration of the first aspect of the present invention, it is possible to control periodic fluctuations in the supply path when a plurality of supply units are driven.

  According to the structure of Claim 2 of this invention, the change of the pressure in a supply path when driving a some supply part is controllable.

  According to the structure of Claim 3 of this invention, the change of the rotation angle of the supply part when a some supply part is driven can be controlled.

  According to the configuration of the fourth aspect of the present invention, even when the driving speeds of the plurality of supply units are different from each other, periodic fluctuations in the supply path when the plurality of supply units are driven are controlled. be able to.

  According to the structure of Claim 5 of this invention, compared with the case where a control means is provided for every supply part, the number of control means can be reduced.

  According to the configuration of the sixth aspect of the present invention, the plurality of supply units are driven as compared with the case where there is no configuration for controlling periodic fluctuations in the supply path when the plurality of supply units are driven. The periodic fluctuations in the supply path can be suppressed.

  According to the configuration of the seventh aspect of the present invention, the plurality of supply units are driven as compared with the case where there is no configuration for controlling periodic fluctuations in the supply path when the plurality of supply units are driven. The periodic fluctuations in the supply path can be emphasized.

  According to the configuration of the eighth aspect of the present invention, it is possible to suppress the image quality defect caused by the change in the pressure of the supply path as compared with the case where the liquid supply device in the configuration is not provided.

1 is a schematic diagram illustrating a configuration of an ink jet recording apparatus according to an embodiment. It is the schematic which shows the structure of the ink supply apparatus which concerns on 1st Embodiment. It is a flowchart which shows the effect | action of the ink supply apparatus which concerns on 1st Embodiment. It is explanatory drawing explaining the case where the pulsation in a supply path is reduced. It is a flowchart which shows the effect | action of the ink supply apparatus which concerns on 2nd Embodiment. It is explanatory drawing explaining the case where the pulsation in the supply path of the ink supply apparatus which concerns on 2nd Embodiment is reduced. It is the schematic which shows the structure of the ink supply apparatus which concerns on 3rd Embodiment. It is a flowchart which shows the effect | action of the ink supply apparatus which concerns on 3rd Embodiment. It is a flowchart which shows the effect | action of the ink supply apparatus which concerns on 4th Embodiment. It is explanatory drawing explaining the case where the pulsation in the supply path of the ink supply apparatus which concerns on 4th Embodiment is emphasized. It is the schematic which shows the structure of the ink supply apparatus which concerns on 5th Embodiment. It is explanatory drawing in order to demonstrate the pump rotation angle of a tube pump. It is a flowchart which shows the effect | action of the ink supply apparatus which concerns on 5th Embodiment.

<First Embodiment>
An example of the first embodiment according to the present invention will be described below with reference to the drawings.

  In the first embodiment, an ink jet recording apparatus that records an image on a recording medium by ejecting ink droplets will be described as an example of an image forming apparatus.

  The image forming apparatus is not limited to the ink jet recording apparatus. As an image forming apparatus, for example, a color filter manufacturing apparatus for manufacturing a color filter by discharging ink or the like on a film or glass, an apparatus for forming an EL display panel by discharging an organic EL solution onto a substrate, a dissolved state There are an apparatus for forming a bump for mounting a component by discharging solder onto a substrate, an apparatus for forming a wiring pattern by discharging a liquid containing metal, and various film forming apparatuses for forming a film by discharging a droplet. Any image forming apparatus that forms an image with a liquid may be used.

(Configuration of inkjet recording apparatus)
First, the configuration of the ink jet recording apparatus will be described. FIG. 1 is a schematic diagram showing the configuration of the ink jet recording apparatus according to the first embodiment.

  As shown in FIG. 1, an inkjet recording apparatus 10 includes a recording medium storage unit 12 that stores a recording medium P such as paper, an image recording unit (image forming unit) 14 that records an image on the recording medium P, and A transport unit 16 that transports the recording medium P from the recording medium storage unit 12 to the image recording unit 14 and a recording medium discharge unit 18 from which the recording medium P on which an image is recorded by the image recording unit 14 are discharged. .

  The image recording unit 14 includes inkjet recording heads 20Y, 20M, 20C, and 20K (hereinafter, referred to as 20Y to 20K) that discharge ink droplets and record an image on a recording medium as an example of a discharging unit that discharges liquid. ing.

  The ink jet recording heads 20Y to 20K have nozzle surfaces 22Y to 22K on which nozzles as an example of ejection ports are formed. The nozzle surfaces 22 </ b> Y to 22 </ b> K have a recordable area that is about the same as or larger than the maximum width of the recording medium P on which image recording with the inkjet recording apparatus 10 is assumed. Note that the width of the recording medium P is the length in the direction orthogonal to the conveyance direction H of the recording medium P (the depth direction of the paper surface in FIG. 1).

  Further, the inkjet recording heads 20Y to 20K are arranged in parallel in the order of yellow (Y), magenta (M), cyan (C), and black (K) from the downstream side in the conveyance direction H of the recording medium P. Ink droplets corresponding to each color are ejected from a plurality of nozzles by a piezoelectric method to record an image. In the inkjet recording heads 20Y to 20K, the configuration for ejecting ink droplets may be a configuration for ejecting ink droplets by other methods such as a thermal method.

  As shown in FIG. 1, the ink jet recording apparatus 10 is provided with ink tanks 21 </ b> Y, 21 </ b> M, 21 </ b> C, and 21 </ b> K (hereinafter referred to as 21 </ b> Y to 21 </ b> K) that store ink of each color as storage units that store liquid. ing. Ink is supplied from the ink tanks 21Y to 21K to the inkjet recording heads 20Y to 20K. As the ink supplied to the inkjet recording heads 20Y to 20K, various inks such as water-based ink, oil-based ink, and solvent-based ink can be used.

  The transport unit 16 transports the recording medium P to the take-out drum 24 that takes out the recording media P in the recording medium storage unit 12 one by one, and the ink jet recording heads 20Y to 20K of the image recording unit 14, and the recording surface (front surface) thereof. It has a transport drum 26 as a transport body facing the ink jet recording heads 20Y to 20K, and a delivery drum 28 for feeding the recording medium P on which an image is recorded to the recording medium discharge section 18. The take-out drum 24, the transport drum 26, and the delivery drum 28 are each configured such that the recording medium P is held on the peripheral surface thereof by electrostatic suction means or non-electrostatic suction means such as suction or adhesion. ing.

  Further, each of the take-out drum 24, the transport drum 26, and the delivery drum 28 is provided with, for example, two sets of grippers 30 as holding means that sandwich and hold the downstream end of the recording medium P in the transport direction. Each of the three drums 24, 26, and 28 is configured to be able to hold the recording medium P on its peripheral surface and up to two sheets in this case by the gripper 30. And the gripper 30 is provided in the recessed part 24A, 26A, 28A formed in the circumferential surface of each drum 24,26,28 2 each.

  Specifically, the rotating shaft 34 is supported along the rotating shaft 32 of each drum 24, 26, 28 at a predetermined position in the recess 24 A, 26 A, 28 A of each drum 24, 26, 28. A plurality of grippers 30 are fixed to the rotating shaft 34 at intervals in the axial direction. Accordingly, when the rotary shaft 34 is rotated in both forward and reverse directions by an actuator (not shown), the gripper 30 is rotated in both forward and reverse directions along the circumferential direction of each drum 24, 26, 28, and the recording medium P is transported downstream. The side end portion is held and separated.

  In other words, the gripper 30 is rotated so that its tip part slightly protrudes from the peripheral surface of each drum 24, 26, 28, so that the peripheral surface of the take-out drum 24 and the peripheral surface of the transport drum 26 face each other. 36, the recording medium P is delivered from the gripper 30 of the take-out drum 24 to the gripper 30 of the transport drum 26, and at a delivery position 38 where the peripheral surface of the transport drum 26 and the peripheral surface of the delivery drum 28 face each other. The recording medium P is delivered from the gripper 30 of the transport drum 26 to the gripper 30 of the delivery drum 28.

  The ink jet recording apparatus 10 includes a maintenance unit (not shown) for maintaining the ink jet recording heads 20Y to 20K. The maintenance unit includes a cap that covers the nozzle surfaces 22Y to 22K of the ink jet recording heads 20Y to 20K, a receiving member that receives preliminarily ejected (empty ejected) droplets, a cleaning member that cleans the nozzle surfaces 22Y to 22K, and ink in the nozzles. The maintenance unit moves to a position facing the ink jet recording heads 20Y to 20K, and performs various types of maintenance.

  Next, an image recording operation (image forming operation) of the inkjet recording apparatus 10 will be described.

  The recording medium P taken out and held one by one by the gripper 30 of the take-out drum 24 from the recording medium container 12 is conveyed while being attracted to the peripheral surface of the take-out drum 24, and at the delivery position 36, the gripper of the take-out drum 24. 30 to the gripper 30 of the transport drum 26.

  The recording medium P held by the gripper 30 of the transport drum 26 is transported to the image recording positions of the ink jet recording heads 20Y to 20K while being attracted to the transport drum 26, and ink droplets are ejected from the ink jet recording heads 20Y to 20K. As a result, an image is recorded on the recording surface.

  The recording medium P having an image recorded on the recording surface is delivered from the gripper 30 of the transport drum 26 to the gripper 30 of the delivery drum 28 at the delivery position 38. Then, the recording medium P held by the gripper 30 of the delivery drum 28 is conveyed while being attracted to the delivery drum 28 and is ejected to the recording medium ejection unit 18. As described above, a series of image recording operations are performed.

(Configuration of ink supply devices 40Y to 40K)
Next, the configuration of ink supply devices 40Y to 40K as an example of a liquid supply device that supplies ink to the inkjet recording heads 20Y to 20K of the image recording unit 14 will be described. Since the ink supply devices 40Y to 40K corresponding to the ink jet recording heads 20Y to 20K have the same configuration, the ink supply device 40Y corresponding to the ink jet recording head 20Y will be described below as an example. FIG. 2 is a schematic diagram illustrating the configuration of the ink supply device 40Y according to the present embodiment.

  As shown in FIG. 2, the ink supply device 40Y includes the above-described ink tank 21Y that stores yellow (Y) ink. One end portion (the right end portion in FIG. 2) of the first supply path 50 through which ink can flow is connected to the ink tank 21Y. One end of a second supply path 60 through which ink can flow is connected to the other end side (left end side in FIG. 2) of the first supply path 50 with respect to the ink tank 21Y. The other end of the second supply path 60 is connected to the inkjet recording head 20Y.

  Thus, ink can be supplied from the ink tank 21Y to the inkjet recording head 20Y through the first supply path 50 and the second supply path 60. In other words, in the present embodiment, the first supply path 50 and the second supply path 60 function as an example of a supply path that supplies ink from the ink tank 21Y to the inkjet recording head 20Y.

  The first supply path 50 branches into two branch supply paths 50A and 50B between the connection position with the second supply path 60 and the ink tank 21Y, and the two branch supply paths 50A and 50B are arranged in parallel. It connects with the 1st supply path 50 so that it may become. A first pump 100 that adjusts the downstream pressure in the first supply path 50 and a second pump 102 that adjusts the downstream pressure in the first supply path 50 are provided in each of the branch supply paths 50A and 50B. Is provided.

  The first pump 100 and the second pump 102 are rotationally driven to supply liquid to the ink jet recording head 20 </ b> Y via the first supply path 50.

  The first pump 100 and the second pump 102 are, for example, pumps (for example, tube pumps) capable of feeding ink in both forward and reverse directions. When the first pump 100 and the second pump 102 send liquid in the forward direction, the downstream part (the left part in FIG. 2) of the first pump 100 and the second pump 102 in the first supply path 50 is pressurized. . When the first pump 100 and the second pump 102 send liquids in the opposite directions, the downstream portion of the first pump 100 and the second pump 102 in the first supply path 50 is decompressed. Further, in a state where the driving of the first pump 100 and the second pump 102 is stopped, the ink circulation between the upstream side portion and the downstream side portion of the first pump 100 and the second pump 102 in the first supply path 50 is performed. Blocked.

  A pressure sensor 104 serving as a detection unit that detects the pressure of the ink in the first supply path 50 is provided on the downstream side of the branch supply paths 50A and 50B of the first supply path 50. For example, the pressure sensor 104 detects pressure based on the nozzle surface 22Y of the inkjet recording head 20Y.

  The ink supply device 40Y controls the first pump driver 200 that drives the first pump 100, the second pump driver 202 that drives the second pump 102, and the driving of the first pump 100 by the first pump driver 200. The first pump controller 300, the second pump controller 302 that controls the driving of the second pump 102 by the second pump driver 202, and the first pump controller 300 and the second pump based on the pressure detected by the pressure sensor 104. And a control unit 400 that controls the controller 302.

  In accordance with the control by the control unit 400, the first pump controller 300 controls the voltage applied to the first pump driver 200, and the first pump driver 200 applies the voltage to the first pump 100 to cause the first pump 100 to operate. Drive to rotate.

  Further, in accordance with control by the control unit 400, the second pump controller 302 controls the voltage applied to the second pump driver 202, and the second pump driver 202 applies the voltage to the second pump 102, so that the second pump 102 is driven to rotate.

  The controller 400 controls the driving speed of the first pump 100 by controlling the voltage applied from the first pump driver 200. For example, the control unit 400 controls the first pump controller 300 to generate a pulse signal corresponding to the driving speed, and controls the driving speed of the first pump 100. By controlling the driving speed of the first pump 100, the flow rate of ink in the first supply path 50 and the second supply path 60 is controlled.

  The controller 400 controls the driving speed of the second pump 102 by controlling the voltage applied from the second pump driver 202. For example, the control unit 400 controls the second pump controller 302 to generate a pulse signal corresponding to the driving speed, and controls the driving speed of the second pump 102. The flow rate of ink in the first supply path 50 and the second supply path 60 is controlled by controlling the driving speed of the second pump 102.

  In the first embodiment, the first pump 100 and the second pump 102 are the same type pumps corresponding to the driving speeds corresponding to the same applied voltage from the first pump driver 200 and the second pump driver 202. An example will be described.

(Operation of the ink supply devices 40Y to 40K)
Next, the operation of the ink supply device 40Y according to the present embodiment will be described. When the ink jet recording apparatus 10 is turned on, the control unit 400 executes an ink supply processing routine shown in FIG.

  First, in step S100, the control unit 400 drives the first pump 100 at a predetermined driving speed for a predetermined period while the second pump 102 is stopped.

  Next, in step S102, the control unit 400 acquires a change in pressure detected by the pressure sensor 104 when the first pump 100 is driven in step S100. For example, the control unit 400 acquires a change in pressure represented by a one-dot chain line in FIG.

  Next, in step S104, the controller 400 drives the second pump 102 at a predetermined driving speed for a predetermined period while the first pump 100 is stopped.

  Next, in step S106, the control unit 400 acquires a change in pressure detected by the pressure sensor 104 when the second pump 102 is driven in step S104. The control part 400 acquires the change of the pressure represented by the broken line of the said FIG. 4 (A), for example.

  Next, in step S108, the control unit 400 acquires the phase of the change in pressure when driving the first pump 100 and the pressure when driving the second pump 102, which are acquired in steps S102 and S106. Based on the phase of the change, the phase difference between the change in pressure when the first pump 100 is driven (dashed line) and the change in pressure when the second pump 102 is driven (dashed line) is calculated. Then, a phase shift amount X necessary for matching the pulsation peaks and valleys is calculated.

  In step S110, the control unit 400 causes the first pump 100 and the second pump 102 so that the phase difference between the first pump and the second pump becomes the phase shift amount X calculated in step S108. Are driven at a predetermined driving speed. The change in pressure detected by the pressure sensor 104 by driving while maintaining such a phase difference is caused by the driving of the first pump 100 and the second pump 102 as shown in FIG. The change in pressure is offset by the change in pressure.

  The ink supply processing routine is executed not only for the ink supply device 40Y but also for the ink supply devices 40M, 40C, and 40K.

  When the image recording operation is performed after the ink supply processing routine is finished, the control unit 400 starts driving the first pump 100 and the second pump 102 at the corresponding driving timing, and also performs the first pump 100 and the first pump. Each pump drive speed is controlled so that the total flow rate with the two pumps 102 becomes a desired flow rate.

  As described above, in the first embodiment, the control unit 400 changes the phase of the pressure change when the first pump 100 is driven and the phase of the pressure change when the second pump 102 is driven. Based on this, the phase difference between the change in pressure when the first pump 100 is driven and the change in pressure when the second pump 102 is driven is calculated, and the phase difference is set to half the pulsation cycle. Therefore, a phase shift amount X necessary for the calculation is calculated. Then, control is performed so that each of the first pump 100 and the second pump 102 is driven at a predetermined driving speed at a driving timing corresponding to the calculated phase shift amount X. Thereby, the change in pressure in the first supply path 50 becomes a change in pressure in which the pressure changes due to the driving of the first pump 100 and the second pump 102 are offset. Therefore, compared with the case where the configuration for adjusting the drive of the pump is not provided, the influence of the pulsation of the pump is reduced, and the change in the pressure of the supply path is suppressed.

  That is, the first pump 100 and the second pump 102 are adjusted so as to adjust the phase difference between the change in pressure when the first pump 100 is driven and the change in pressure when the second pump 102 is driven. By supplying ink under drive control, the influence of pulsation due to pump driving is reduced, and a desired ink flow rate is realized.

<Second Embodiment>
Next, an example of the second embodiment will be described.
(Configuration of inkjet recording apparatus)
The inkjet recording apparatus of the second embodiment is mechanically similar to the inkjet recording apparatus 10 of the first embodiment described above, and the first pump 100 and the second pump of the ink supply apparatus. 102 is different. For this reason, the second embodiment is also described as the ink jet recording apparatus 10, and basically the same member as the ink jet recording apparatus 10 of the first embodiment described above is the same as the first embodiment. The same reference numerals are given and description thereof is omitted.

(Configuration of ink supply devices 42Y to 42K)
As in the first embodiment, since the ink supply devices 42Y to 42K have the same configuration, the ink supply device 42Y corresponding to the ink jet recording head 20Y will be described below as an example.

  Here, parts different from the ink supply apparatus 40Y according to the first embodiment will be described, and parts having the same functions as those of the ink supply apparatus 40Y will be denoted by the same reference numerals and description thereof will be omitted as appropriate.

  The second embodiment is different from the first embodiment in that the first pump 100 and the second pump 102 have different liquid feeding capabilities and different periods of pulsation generated during driving.

  Other configurations are the same as those in the first embodiment, and thus description thereof is omitted.

(Operation of the ink supply devices 42Y to 42K)
Next, the operation of the second embodiment will be described.
In addition, about the procedure similar to 1st Embodiment, the same step number as 1st Embodiment is provided and the description is abbreviate | omitted. However, the same steps may be described.

  When power is turned on to the inkjet recording apparatus 10, the control unit 400 executes an ink supply processing routine shown in FIG.

  First, in step S100, the controller 400 drives the first pump 100 with a predetermined applied voltage from the first pump driver 200 for a predetermined period while the second pump 102 is stopped.

  Next, in step S102, the control unit 400 acquires a change in pressure detected by the pressure sensor 104 when the first pump 100 is driven in step S100. For example, the control unit 400 acquires a change in pressure represented by a one-dot chain line in FIG.

  Next, in step S104, the control unit 400 drives the second pump 102 with a predetermined applied voltage from the second pump driver 202 for a predetermined period while the first pump 100 is stopped. .

  Next, in step S106, the control unit 400 acquires a change in pressure detected by the pressure sensor 104 when the second pump 102 is driven in step S104. For example, the control unit 400 acquires a change in pressure represented by a broken line in FIG.

  In step S208, as shown in FIG. 6A, the first pump 100 is driven based on the change in pressure when the control unit 400 drives the first pump 100 acquired in step S102. The period of change in pressure when it is applied is calculated. Then, based on the change in pressure when the second pump 102 acquired in step S106 is driven by the control unit 400, the second pump 102 is driven as shown in FIG. 6A. The period of change in pressure is calculated.

  Next, in step S210, the control unit 400 calculates the pressure change cycle when the first pump 100 is driven and the pressure change when the second pump 102 is driven, which are calculated in step S208. A speed ratio between the driving speed of the first pump 100 and the driving speed of the second pump 102 is calculated based on the ratio of the periods so that the periods correspond.

  In step S212, based on the speed ratio calculated in step S210, the controller 400 applies the voltage applied from the first pump driver 200 to the first pump 100 and the second pump driver 202 applies to the second pump 102. The driving speed of each of the first pump 100 and the second pump 102 is adjusted by adjusting the voltage to be adjusted.

  Next, in step S214, the control unit 400 obtains the phase of the change in pressure when the first pump 100 is driven and the pressure when the second pump 102 is driven, acquired in steps S102 and S106. Based on the phase of the change, the second pump at the change in pressure when the first pump 100 is driven at the drive speed adjusted at step S212 (the one-dot chain line) and at the drive speed adjusted at step S212. A phase difference with a change in pressure (broken line) when driving 102 is calculated, and a phase shift amount X necessary to correspond the pulsation peaks and valleys is calculated (see FIG. 6B).

  In step S216, the control unit 400 drives each of the first pump 100 and the second pump 102 at the adjusted driving speed at the driving timing corresponding to the phase shift amount X calculated in step S108. To do. At this time, as shown in FIG. 6C, the change in pressure detected by the pressure sensor 104 is a change in pressure that cancels out the pressure change due to the driving of each of the first pump 100 and the second pump 102. Become.

  The ink supply processing routine is executed not only for the ink supply device 42Y but also for the ink supply devices 42M, 42C, and 42K.

  When the image recording operation is performed after the ink supply processing routine is completed, the control unit 400 drives the first pump 100 and the second pump 102 with a predetermined phase difference, and the first pump 100 and the first pump 100. The first pump 100 and the second pump 102 are driven at drive speeds adjusted according to the speed ratio of the pump drive speeds so that the total flow rate with the two pumps 102 becomes a desired flow rate.

  As described above, in the second embodiment, when the pump capacity is different between the first pump 100 and the second pump 102, the voltage applied from the first pump driver 200 to the first pump 100 by the control unit 400. And the driving speed of each of the first pump 100 and the second pump 102 is adjusted by adjusting the voltage applied from the second pump driver 202 to the second pump 102. Then, control is performed so that each of the first pump 100 and the second pump 102 is driven at the adjusted drive speed at the drive timing corresponding to the calculated phase shift amount X. Thereby, the change in pressure in the first supply path 50 becomes a change in pressure in which the pressure changes due to the driving of the first pump 100 and the second pump 102 are offset. For this reason, even when the first pump 100 and the second pump 102 have different capacities, the change in the pressure in the supply path is suppressed as compared with the case where the configuration for adjusting the driving of the pump is not provided.

  That is, the drive speed of the first pump 100 and the second pump 102 and the phase difference between the change in pressure when the first pump 100 is driven and the change in pressure when the second pump 102 is driven are adjusted. As described above, by driving and controlling the first pump 100 and the second pump 102, the influence of pulsation due to the pump drive is reduced, and a desired ink flow rate is realized.

<Third Embodiment>
Next, an example of the third embodiment will be described.
(Configuration of inkjet recording apparatus)
As shown in FIG. 7, the ink jet recording apparatus of the third embodiment is mechanically similar to the ink jet recording apparatus 10 of the first embodiment described above, and the pump of the ink supply apparatus The difference is that the controller 310 controls the first pump driver 200 and the second pump driver 202 via the first switch 500 and the second switch 502. Therefore, the third embodiment is also described as the ink jet recording apparatus 10, and basically the same members as those of the ink jet recording apparatus 10 of the first embodiment described above are the same as the first embodiment. The same reference numerals are given and description thereof is omitted.

(Configuration of ink supply devices 43Y to 43K)
As in the first embodiment, the ink supply devices 43Y to 43K have the same configuration, and therefore, the ink supply device 43Y corresponding to the ink jet recording head 20Y will be described below as an example.

  Here, parts different from the ink supply apparatus 40Y according to the first embodiment will be described, and parts having the same functions as those of the ink supply apparatus 40Y will be denoted by the same reference numerals and description thereof will be omitted as appropriate.

  The first switch 500 connects or disconnects the first pump driver 200 and the pump controller 310 according to control by the control unit 400.

  The second switch 502 connects or disconnects the second pump driver 202 and the pump controller 310 according to control by the control unit 400.

  In accordance with control by the control unit 400, the pump controller 310 controls the voltage applied from the first pump driver 200 when connected to the first pump driver 200 via the first switch 500, and the first pump driver 200 is controlled. Applies a voltage to the first pump 100 to rotate the first pump 100.

  Further, in accordance with control by the control unit 400, the pump controller 310 controls the applied voltage from the second pump driver 202 when connected to the second pump driver 202 via the second switch 502, and the second pump The driver 202 applies a voltage to the second pump 102 to drive the second pump 102 to rotate.

  Other configurations are the same as those in the first embodiment, and thus description thereof is omitted.

(Operation of the ink supply devices 43Y to 43K)
Next, the operation of the third embodiment will be described.
In addition, about the procedure similar to 1st Embodiment, the same step number as 1st Embodiment is provided and the description is abbreviate | omitted. However, the same steps may be described.

  When the power is turned on to the inkjet recording apparatus 10, the control unit 400 executes an ink supply processing routine shown in FIG.

  First, in step S300, the control unit 400 turns on the first switch 500 and turns off the second switch 502 to connect the first pump driver 200 and the pump controller 310, and for a predetermined period, The first pump 100 is driven at a predetermined driving speed.

  Next, in step S102, the control unit 400 acquires a change in pressure detected by the pressure sensor 104 when the first pump 100 is driven in step S300. For example, the control unit 400 acquires a change in pressure represented by a one-dot chain line in FIG.

  Next, in step S304, the control unit 400 turns on the second switch 502 and turns off the first switch 500 to connect the second pump driver 202 and the pump controller 310, and for a predetermined period. The second pump 102 is driven at a predetermined driving speed.

  Next, in step S106, the control unit 400 acquires a change in pressure detected by the pressure sensor 104 when the second pump 102 is driven in step S304. The control part 400 acquires the change of the pressure represented by the broken line of the said FIG. 4 (A), for example.

  Next, in step S108, the control unit 400 acquires the change in pressure when the first pump 100 is driven and the change in pressure when the second pump 102 is driven, acquired in steps S102 and S106. Based on the above, the phase difference between the change in pressure when the first pump 100 is driven (dashed line) and the change in pressure when the second pump 102 is driven (dashed line) is calculated, and the peak of pulsation And a phase shift amount X required to correspond to the valley.

  In step S110, the control unit 400 turns on each of the first switch 500 and the second switch 502 at the drive timing corresponding to the phase shift amount X calculated in step S108, and the first pump 100 is turned on. And the second pump 102 are driven at a predetermined driving speed, and then the first pump 100 and the second pump 102 are controlled to stop, and the ink supply processing routine is ended. At this time, the change in pressure detected by the pressure sensor 104 is a change in pressure obtained by canceling out the pressure change due to the driving of each of the first pump 100 and the second pump 102 as shown in FIG. It becomes.

  The ink supply processing routine is executed not only for the ink supply device 43Y but also for the ink supply devices 43M, 43C, and 43K.

  When the image recording operation is performed after the ink supply processing routine is completed, the control unit 400 starts driving the first pump 100 and the second pump 102, and the first pump 100 and the second pump 102. Each pump drive speed is controlled so that the total flow rate becomes a desired flow rate.

  Thus, in the third embodiment, the control unit 400 turns on the first switch 500, connects the first pump driver 200 and the pump controller 310, and drives the first pump 100. A change in pressure detected by the sensor 104 is acquired. Then, the switch 502 is turned on, the second pump driver 202 and the pump controller 310 are connected, and the change in pressure detected by the pressure sensor 104 when the second pump 102 is driven is acquired. Then, at the drive timing corresponding to the calculated phase shift amount X, each of the first switch 500 and the second switch 502 is turned on, and each of the first pump 100 and the second pump 102 is determined in advance. Control to drive at the driving speed. As a result, the pressure change in the first supply path 50 becomes a pressure change in which the pressure changes due to the respective driving of the first pump 100 and the second pump 102 are offset, and the driving of the pump is adjusted. Compared with the case where it does not, the influence of the pulsation of the pump is reduced, and the change in the pressure of the supply path is suppressed.

  Thereby, compared with the case where a pump controller is provided for every pump, the number of pump controllers is reduced.

<Fourth embodiment>
Next, an example of the fourth embodiment will be described.
(Configuration of inkjet recording apparatus)
The inkjet recording apparatus of the fourth embodiment is mechanically similar to the inkjet recording apparatus 10 of the first embodiment described above, and the operation of the control unit 400 of the ink supply apparatus is different. Yes. For this reason, the fourth embodiment is also described as the ink jet recording apparatus 10, and basically the same member as the ink jet recording apparatus 10 of the first embodiment described above is the same as the first embodiment. The same reference numerals are given and description thereof is omitted.

(Configuration of ink supply devices 44Y to 44K)
Similarly to the first embodiment, the ink supply devices 44Y to 44K have the same configuration, and therefore, the ink supply device 44Y corresponding to the ink jet recording head 20Y will be described below as an example.

  Since the fourth embodiment has the same configuration as the ink supply device 40Y according to the first embodiment, the description thereof is omitted.

(Operation of the ink supply devices 44Y to 44K)
Next, the operation of the fourth embodiment will be described.
In addition, about the procedure similar to 1st Embodiment, the same step number as 1st Embodiment is provided and the description is abbreviate | omitted. However, the same steps may be described.

  When the power is turned on to the inkjet recording apparatus 10, the control unit 400 executes an ink supply processing routine shown in FIG.

  In step S102, the control unit 400 acquires a change in pressure detected by the pressure sensor 104 when the first pump 100 is driven in step S100. For example, the control unit 400 acquires a change in pressure represented by a one-dot chain line in FIG.

  In step S106, the control unit 400 acquires a change in pressure detected by the pressure sensor 104 when the second pump 102 is driven in step S104. For example, the control unit 400 acquires a change in pressure represented by a broken line in FIG.

  In step S408, based on the change in pressure when the first pump 100 is driven and the change in pressure when the second pump 102 is driven, acquired by the control unit 400 in steps S102 and S106. The phase difference between the change in pressure when the first pump 100 is driven (one-dot chain line) and the change in pressure when the second pump 102 is driven (dashed line) is calculated. A phase shift amount X necessary for the calculation is calculated.

  In step S110, each of the first pump 100 and the second pump 102 is driven at a predetermined driving speed at a driving timing corresponding to the phase shift amount X calculated in step S408 by the control unit 400. Drive. At this time, as shown in FIG. 10B, the pressure change detected by the pressure sensor 104 is a pressure change in which pressure changes due to driving of the first pump 100 and the second pump 102 are emphasized. Become.

  The ink supply processing routine is executed not only for the ink supply device 44Y but also for the ink supply devices 44M, 44C, and 44K.

  When the image recording operation is performed after the ink supply processing routine is finished, the control unit 400 starts driving the first pump 100 and the second pump 102 at the corresponding driving timing, and also performs the first pump 100 and the first pump. Each pump drive speed is controlled so that the total flow rate with the two pumps 102 becomes a desired flow rate.

  Thus, in the fourth embodiment, the control unit 400 performs the first change based on the change in pressure when the first pump 100 is driven and the change in pressure when the second pump 102 is driven. A phase shift amount necessary to calculate a phase difference between a change in pressure when the first pump 100 is driven and a change in pressure when the second pump 102 is driven, and to set the phase difference to zero. Calculate X. Then, control is performed so that each of the first pump 100 and the second pump 102 is driven at a predetermined driving speed at a driving timing corresponding to the calculated phase shift amount X. Thereby, the change in the pressure in the first supply path 50 becomes a change in pressure that is a combination of the pressure changes caused by the driving of the first pump 100 and the second pump 102, and there is no configuration for adjusting the driving of the pump. Compared to the case, the influence of pulsation is emphasized.

  That is, the first pump 100 and the second pump 102 are driven by adjusting the phase difference between the change in pressure when the first pump 100 is driven and the change in pressure when the second pump 102 is driven. By controlling and feeding the ink, the influence of pulsation due to the pump drive increases. Thereby, the effect becomes higher at the time of the operation in which the pulsation component at the time of liquid feeding contributes such as the bubble discharging operation in the supply path.

  The configuration for calculating the amount of phase shift necessary to make the above phase difference zero and controlling the pump drive is the same as that in the second and third embodiments described above and the fifth described later. The same can be applied to the embodiment.

<Fifth embodiment>
Next, an example of the fifth embodiment will be described.
(Configuration of inkjet recording apparatus)
The ink jet recording apparatus according to the fifth embodiment is mechanically similar to the ink jet recording apparatus 10 according to the first embodiment described above. As shown in FIG. The first means for detecting the position where the pulsation of the first pump 100 that is rotationally driven (for example, an encoder that detects a specific rotation angle) and the position where the pulsation of the second pump that is rotationally driven is detected. 2 points (for example, an encoder for detecting a specific rotation angle). For this reason, the fifth embodiment is also described as the ink jet recording apparatus 10, and basically the same members as those of the ink jet recording apparatus 10 of the first embodiment described above are the same as those in the first embodiment. The same reference numerals are given and description thereof is omitted.

(Configuration of ink supply devices 45Y to 45K)
As in the first embodiment, the ink supply devices 45Y to 45K have the same configuration, and therefore the ink supply device 45Y corresponding to the ink jet recording head 20Y will be described below as an example.

  The ink supply device 45Y includes a first means 70 for detecting a position where the pulsation of the first pump 100 that is driven to rotate and a second means 72 for detecting a position where the pulsation of the second pump 102 that is driven to rotate are detected. I have.

  The first means 70 is, for example, an encoder that detects a specific rotation angle of the first pump 100, and the correspondence between the pulsation in the supply path and the change in the rotation angle of the first pump 100 is obtained in advance. . That is, the correspondence between the specific rotation angle of the first pump 100 and the position of the first pump 100 where pulsation in the supply path occurs is obtained in advance from the correspondence. Here, a case where the first pump 100 is a tube pump will be described as an example.

  The conceptual diagram for demonstrating operation | movement of a tube pump is shown to FIG. 12 (A) and (B). The tube pump is wound around the outer periphery of the tube (supply path 50A) in a crushed state. As shown in FIGS. 12A and 12B, the roller 100A of the tube pump rotates with the tube being crushed, and squeezes the tube to send ink downstream.

  The second means 72 is, for example, an encoder that detects a specific rotation angle of the second pump 102, and the correspondence between the pulsation in the supply path and the change in the rotation angle of the second pump 102 is obtained in advance. . That is, the correspondence between the specific rotation angle of the second pump 102 and the position of the second pump 102 where the pulsation in the supply path is generated is obtained in advance from the correspondence. When the second pump 102 is a tube pump, the second means, like the first means, the tube pump roller 102A crushes the tube as shown in FIGS. 12 (A) and 12 (B). Rotate in a state of squeezing, squeeze the tube and send ink downstream.

  By detecting the rotation angle by the first means 70 and the second means 72, the positions of the first pump 100 and the second pump 102 where the pulsation occurs are detected.

  Other configurations are the same as those in the first embodiment, and thus description thereof is omitted.

(Operation of the ink supply devices 45Y to 45K)
Next, the operation of the fifth embodiment will be described.
In addition, about the procedure similar to 1st Embodiment, the same step number as 1st Embodiment is provided and the description is abbreviate | omitted. However, the same steps may be described.

  When power is turned on to the inkjet recording apparatus 10, the control unit 400 executes an ink supply processing routine shown in FIG.

  In step S502, the control unit 400 acquires a change in the rotation angle of the first pump 100 detected by the first means 70 when the first pump 100 is driven in step S100.

  In step S506, the control unit 400 acquires a change in the rotation angle of the second pump 102 detected by the second means 72 when the second pump 102 is driven in step S104.

  Next, in step S508, the control unit 400 drives the second pump 102 and the change in the rotation angle of the first pump 100 obtained when the first pump 100 is driven, acquired in steps S502 and S506. Phase difference between the change in the rotation angle when the first pump 100 is driven and the change in the rotation angle when the second pump 102 is driven based on the change in the rotation angle of the second pump 102 , And a rotational angle deviation amount X necessary for matching the pulsation peaks and valleys is calculated.

  In step S510, the control unit 400 controls each of the first pump 100 and the second pump 102 at a predetermined driving speed at a driving timing corresponding to the rotational angle deviation amount X calculated in step S508. Drive with. At this time, the pressure change detected by the pressure sensor 104 is a pressure change in which the pressure changes due to the driving of the first pump 100 and the second pump 102 are offset.

  The ink supply processing routine is executed not only for the ink supply device 45Y but also for the ink supply devices 45M, 45C, and 45K.

  When the image recording operation is performed after the ink supply processing routine is finished, the control unit 400 starts driving the first pump 100 and the second pump 102 at the corresponding driving timing, and also performs the first pump 100 and the first pump. Each pump drive speed is controlled so that the total flow rate with the two pumps 102 becomes a desired flow rate.

  As described above, in the fifth embodiment, the controller 400 changes the rotation angle of the first pump 100 when the first pump 100 is driven and the second pump when the second pump 102 is driven. Based on the change in the rotation angle of 102, the phase difference between the change in the rotation angle when the first pump 100 is driven and the change in the rotation angle when the second pump 102 is driven is calculated. A rotational angle deviation amount X required to make the phase difference half the pulsation period is calculated. Then, control is performed so that each of the first pump 100 and the second pump 102 is driven at a predetermined driving speed at a driving timing corresponding to the calculated rotational angle deviation amount X. As a result, the pressure change in the first supply path 50 becomes a pressure change in which the pressure changes due to the respective driving of the first pump 100 and the second pump 102 are offset, and the driving of the pump is adjusted. Compared with the case where it does not, the influence of the pulsation of the pump is reduced, and the change in the pressure of the supply path is suppressed.

  In addition, the structure which adjusts the drive of a pump using the 1st means 70 which measures the rotation angle of the 1st pump 100, and the 2nd means 72 which measures the rotation angle of a 2nd pump is said 2nd, The same applies to the third and fourth embodiments.

  In the above-described embodiment, the change in pressure or rotation angle when the first pump 100 is driven and the change in pressure or rotation angle when the second pump 102 is driven. The case where the phase difference is calculated and the phase shift amount X necessary for setting the phase difference to be half or 0 of the pulsation period has been described as an example. However, the present invention is not limited to this. The driving of the pump may be adjusted by calculating the phase shift amount X so as to be a value corresponding to half of the cycle or 0.

  In the above embodiment, the case where the change in the pressure in the supply path or the change in the rotation angle of the pump is acquired has been described as an example. However, the present invention is not limited to this and is accompanied by the driving of a plurality of pumps. You may acquire the other physical quantity which shows the pulsation in a supply path. For example, it may be controlled to reduce the influence of pump pulsation by acquiring a change in the flow of ink in the supply path.

  In the above embodiment, the case where the inkjet recording apparatus 10 executes the ink supply processing routine when the inkjet recording apparatus 10 is turned on has been described as an example. However, the present invention is not limited to this. The ink supply processing routine may be executed at a timing other than power-on.

  The present invention is not limited to the above-described embodiment, and various modifications, changes, and improvements can be made. For example, the above-described modified examples may be appropriately combined.

10 Inkjet recording apparatus (an example of an image forming apparatus)
16 Conveying unit 20Y Inkjet recording head (an example of an ejection unit)
40Y ink supply device (an example of a liquid supply device)
42Y ink supply device (an example of a liquid supply device)
43Y ink supply device (an example of a liquid supply device)
44Y ink supply device (an example of a liquid supply device)
45Y ink supply device (an example of a liquid supply device)
50 1st supply path (an example of a supply path)
50A, 50B branch supply path (example of supply path)
60 Second supply path (an example of a supply path)
70 1st means (an example of a detection means)
72 2nd means (an example of a detection means)
100 1st pump (an example of a supply part)
102 Second pump (an example of a supply unit)
104 Pressure sensor (an example of detection means)
200 First pump driver 202 Second pump driver 300 First pump controller (an example of control means)
302 Second pump controller (an example of control means)
310 Pump controller (an example of control means)
400 Control unit (an example of control means)
500 1st switch (an example of a switching unit)
502 Second switch (an example of a switching unit)

Claims (8)

A supply path for supplying liquid to a discharge section having a discharge port;
A plurality of supply sections that are provided in parallel to the supply path and supply liquid to the discharge section via the supply path;
Detecting means for detecting periodic fluctuations in the supply path as the supply unit is driven;
For each of the plurality of supply units, the periodic variation detected by the detection means when the supply unit is driven is acquired, and the phase of the periodic variation acquired for each of the plurality of supply units Based on the control means for controlling the driving of the plurality of supply units, so that the phase difference of the periodic fluctuations when the plurality of supply units are driven becomes a predetermined phase difference;
Including a liquid supply device. The detection means detects a change in pressure in the supply path as a periodic fluctuation in the supply path,
For each of the plurality of supply units, the control unit acquires a change in pressure detected by the detection unit when the supply unit is driven, and the control unit acquires the change in the pressure acquired for each of the plurality of supply units. 2. The drive of the plurality of supply units is controlled based on the phase of change so that the phase difference of the change in pressure when the plurality of supply units is driven becomes a predetermined phase difference. The liquid supply apparatus as described. The plurality of supply units are provided in parallel to the supply path, and rotate to drive the liquid to the discharge unit via the supply path.
The detection means detects a change in the rotation angle of the supply unit that is previously determined to correspond to the periodic variation for each of the plurality of supply units as a periodic variation in the supply path,
The control means acquires, for each of the plurality of supply sections, the change in the rotation angle detected by the detection means when the supply section is driven, and the control section acquires the change obtained for each of the plurality of supply sections. Based on the phase of the change of the rotation angle, the drive of the plurality of supply units is controlled so that the phase difference of the change of the rotation angle when the plurality of supply units is driven becomes a predetermined phase difference. The liquid supply apparatus according to claim 1. The plurality of supply units are driven at different driving speeds to supply liquid to the discharge unit via the supply path,
The control means is configured to drive the plurality of supply units based on a phase of the periodic variation acquired for each of the plurality of supply units and a ratio of the periodic variation periods. A phase difference of the periodic fluctuations when the plurality of supply units are driven so that each of the periodic fluctuation periods corresponds and each of the periodic fluctuation periods corresponds is predetermined. The liquid supply apparatus according to any one of claims 1 to 3, wherein driving of the plurality of supply units is controlled so as to achieve a phase difference. A plurality of drive units that are provided for each of the plurality of supply units and that drive the supply unit;
A plurality of switching units provided for each of the plurality of driving units, for switching whether to connect between the driving unit and the control means;
The control means performs control so as to drive the driving unit connected via the switching unit among the plurality of driving units, and the phase difference when driving the plurality of supply units 5. The liquid according to claim 1, wherein connection timing between the switching unit and each of the plurality of supply units is controlled with respect to each of the plurality of supply units so as to be a predetermined phase difference. Feeding device.   The control unit controls driving of the plurality of supply units so that the phase difference when the plurality of supply units is driven becomes a value corresponding to half of a period of the periodic fluctuation. The liquid supply apparatus of any one of 1-5.   The said control means controls the drive of these supply parts so that the said phase difference when driving these supply parts may become a value corresponding to 0. The liquid supply apparatus according to 1. A transport unit for transporting the recording medium;
An ejection unit that ejects liquid onto a recording medium conveyed by the conveyance unit;
The liquid supply apparatus according to any one of claims 1 to 7, wherein a liquid is supplied to the ejection unit.
An image forming apparatus comprising:

Images