JP2007230041A - Liquid jet device and auxiliary storage means - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid jet device which can inhibit poor ejection by air bubbles which remained in a liquid jet head and decrease a liquid scrappage rate, and to provide an auxiliary storage means. <P>SOLUTION: A printer 1 includes a recording head 5 which ejects ink drops, a cartridge 11 which stores ink, an ink channel 15 which supplies ink stored in a cartridge 11 to a recording head 5, and a sub-tank which stores ink supplied from a cartridge 11 temporarily. Moreover, in a midstream of an ink channel 15, a tube pump 20 which supplies ink to a recording head 5 from a cartridge 11 and delivers air which accumulates in a sub-tank 21 to a cartridge 11 is arranged. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a liquid ejecting apparatus and auxiliary storage means.

  As a liquid ejecting apparatus that ejects liquid from a liquid ejecting head to a target, there is an ink jet printer (hereinafter simply referred to as a printer). The printer supplies ink from a cartridge storing ink as liquid to a recording head as a liquid ejecting head mounted on the carriage. Then, the recording head is driven to eject ink onto the paper as a target.

  However, air bubbles may be mixed into the ink supplied to the recording head due to the attachment / detachment of the cartridge and the gas permeability of the material of each member. A filter for filtering ink is provided immediately above the recording head, but bubbles that have passed through the filter by cleaning may remain in the recording head. When bubbles are mixed in the recording head, printing defects such as missing dots occur. Also, if bubbles accumulated on the filter become large and block the flow path, ink is not supplied to the head, resulting in poor printing.

On the other hand, Patent Document 1 describes a filter in which protrusions are arranged in a space where air bubbles tend to stay. This filter is provided in an on-carriage inkjet printer in which a cartridge is mounted on a carriage. In this method, the bubble discharge property is improved by the projecting portion of the filter occupying a space in which bubbles tend to stay. Further, in Patent Document 2, in an ink jet printer provided with a buffer tank on the upstream side of a recording head, a printer that discharges air stored in a bubble storage chamber above the buffer tank to the outside through an exhaust cap. Are listed.
JP 2002-218809 A JP-A-2005-246828

  However, in the printer described in Patent Document 1, it is possible to easily remove bubbles accumulated on the filter, but in order to discharge the generated bubbles, it is necessary to perform cleaning for sucking ink from the nozzles of the recording head. There is. The ink sucked by the cleaning is stored in a dedicated tank as waste ink. In addition, since bubbles pass through the recording head during cleaning, bubbles may remain in the recording head, resulting in ejection failure. Further, since the bubbles are discharged by cleaning, the ink discard rate increases.

In the printer described in Patent Document 2, the ink in the buffer tank is discharged to the outside together with the air in the bubble storage chamber. For this reason, the ink discard rate may increase.
The present invention has been made in view of the above problems, and an object thereof is to provide a liquid ejecting apparatus and auxiliary storage means that can prevent ejection failure due to bubbles remaining in the liquid ejecting head and reduce the liquid discard rate. There is to do.

The present invention provides a liquid jet head that discharges liquid, a main storage unit that stores liquid, a flow path that supplies the liquid stored in the main storage unit to the liquid jet head, and the main storage unit. An auxiliary storage means for temporarily storing the liquid, wherein the liquid in the main storage means is supplied to the ejection head via the flow path, and the gas retained in the auxiliary storage means Pump means for delivering to the main storage means via the flow path was provided.

  According to this, the liquid is supplied from the main storage unit to the ejection head by the pump unit, and the gas retained in the auxiliary storage unit is sent to the main storage unit. For this reason, by discharging the gas retained in the auxiliary storage means, it is possible to prevent bubbles from being mixed into the liquid supplied to the ejection head. Further, since the gas is discharged to the main storage means, even when the liquid in the auxiliary storage means is discharged at the time of gas discharge, the discharged liquid can be stored in the main storage means. Can be reused as a liquid. For this reason, the liquid disposal rate of the main storage means can be reduced. Further, since the liquid and the gas are supplied or discharged through the same flow path, for example, a flow path for gas discharge can be omitted.

  In the liquid ejecting apparatus, the main storage unit is positioned vertically above the liquid supply port, a liquid supply port for leading the liquid to the auxiliary storage unit, and a liquid supply port. And a storage section for storing the gas discharged from the auxiliary storage means.

  According to this, the gas discharged | emitted from the auxiliary storage means is stored by the part located in the perpendicular direction upper direction than the liquid supply port among the storage parts of the main storage means. For this reason, the gas stored in the main storage means is not sent back from the liquid supply port to the auxiliary storage means and the ejection head side.

  In this liquid ejecting apparatus, the auxiliary storage means communicates with the pump means, and the internal volume can be changed, and the variable volume portion urged in the direction in which the volume is increased, and the variable volume portion, A liquid introduction part for introducing the liquid supplied from the main storage means side, a discharge part for discharging the gas retained in the variable volume part to the main storage means side, and a liquid outlet part for supplying liquid to the ejection head And, when the pump means is driven, the gas in the variable volume part is discharged to the main storage means side to reduce the internal volume of the variable volume part, and the biasing force of the reduced variable volume part, The liquid is introduced into the variable volume portion from the main storage means side by driving the pump means.

  According to this, as the pump means is driven, the variable volume portion discharges the internal gas and contracts. Further, since the variable volume portion is biased in the direction of enlarging the reduced volume, a negative pressure is generated when the variable volume portion is reduced, and the negative pressure and the pump drive suck the liquid. For this reason, a relatively large amount of liquid can be stored in the auxiliary storage means in a short time.

In the liquid ejecting apparatus, the variable volume portion includes a biasing unit that biases the internal volume in a direction in which the internal volume increases.
According to this, the variable volume portion can be reliably urged in the direction in which the internal volume is increased by the urging means.

  In this liquid ejecting apparatus, the discharge portion for discharging the gas in the variable volume portion and the liquid introduction portion for introducing the liquid into the variable volume portion are integrated, and the opening for discharging the gas and introducing the liquid is Between the inner bottom surface of the variable volume part and the opening, it is provided at a position where a space for filling liquid is held.

  According to this, the discharge part which discharges | emits gas, and the liquid introduction part are provided integrally. Moreover, the opening part of the discharge part (or the liquid introduction part) is provided at a position where a space for filling the liquid is held between the inner bottom surface of the variable volume part and the opening part. For this reason, the gas retained on the liquid surface in a state where a predetermined amount of liquid is held in the variable volume portion can be discharged from the opening.

  In the liquid ejecting apparatus, the variable volume portion includes an expansion / contraction member that expands and contracts in a predetermined direction, and further includes detection means for detecting a maximum volume and a minimum volume of the expansion / contraction member.

  According to this, since the maximum volume and the minimum volume are detected by the detection means, it is possible to manage the amount of liquid or gas in the variable volume portion by controlling the pump means at the time of maximum volume detection or minimum volume detection. it can.

  In the liquid ejecting apparatus, the detection unit includes a first switch that contacts a part of the expansion / contraction member when the internal volume of the expansion / contraction member is a minimum volume, and And a second switch in contact with a part of the elastic member.

  According to this, a detection means is comprised from the 1st switch and 2nd switch which contact a part of expansion-contraction member in the case of the minimum volume or the maximum volume. For this reason, the maximum volume and the minimum volume can be detected by effectively utilizing the extension operation and the reduction operation of the elastic member.

The liquid ejecting apparatus further includes a restricting unit that abuts the variable volume portion and restricts further expansion of the internal volume when the internal volume of the variable volume portion reaches an upper limit value.
According to this, when the internal volume reaches the upper limit value, further expansion of the internal volume is regulated by the regulating means. For this reason, damage to the variable volume portion or the like can be prevented.

  In this liquid ejecting apparatus, by driving the pump means in one direction, a liquid supply operation for supplying liquid to the auxiliary storage means, and by driving the pump means in the other direction, gas in the auxiliary storage means The gas storage operation for discharging the gas to the main storage means is alternately repeated to fill the auxiliary storage means with liquid.

  According to this, the liquid supply operation and the gas discharge operation are alternately repeated to fill the auxiliary storage means with the liquid. For this reason, the liquid can be filled in a state where a large amount of gas does not remain in the auxiliary storage means.

In the liquid ejecting apparatus, the gas is discharged from the auxiliary storage unit by performing the gas discharge operation and the liquid supply operation every predetermined period.
According to this, the gas discharge operation and the liquid supply operation are performed every predetermined time to perform the gas venting, so that it is possible to supply only the liquid to the ejection head.

  In the liquid ejecting apparatus, when the liquid is ejected by the ejecting head, and the detecting unit detects the minimum volume of the variable volume portion, the pump unit is driven in one direction so that the liquid is stored in the auxiliary storing unit. Supply.

  According to this, when the liquid in the auxiliary storage means is consumed and the minimum volume of the variable volume portion is detected, the liquid is supplied by the pump means. For this reason, a certain amount or more of liquid can always be stored in the auxiliary storage means.

  In this liquid ejecting apparatus, even if the elapsed time for performing the liquid supply operation for driving the pump means in one direction and supplying the liquid to the auxiliary storage means exceeds the maximum required time, the variable volume portion is detected by the detection means. When the maximum volume is not detected, the liquid consumption state of the main storage means is detected.

According to this, when the detection means does not detect the maximum volume of the variable volume and the pump means is driven for the maximum required time but does not reach the maximum volume, the liquid storage state of the main storage means is detected. For this reason, the liquid consumption state of the main storage means can be detected with a simple configuration.

  The auxiliary storage means of the present invention is capable of changing the internal volume, and has a variable volume portion urged in a direction in which the volume expands, and a liquid introduction portion that introduces liquid supplied from the outside into the variable volume portion And a discharge part for discharging the gas staying in the variable volume part to the outside and a liquid outlet part for supplying the liquid to the outside, and as the gas in the variable volume part is discharged, The internal volume is reduced, and a liquid is introduced into the variable volume part from the outside by a negative pressure based on the biasing force of the reduced variable volume part.

  According to this, the variable volume portion is reduced by discharging the internal gas. Further, since the variable volume portion is biased in the direction of expanding the reduced volume, a negative pressure is generated when the variable volume portion is reduced, and the liquid is sucked by the negative pressure. For this reason, a relatively large amount of liquid can be sucked into the auxiliary storage means in a short time.

Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS.
FIG. 1 is a diagram illustrating an outline of an ink jet printer (hereinafter referred to as a printer 1) as a liquid ejecting apparatus. As shown in FIG. 1, the printer 1 includes a pair of frame plates 2, and rod-shaped guide members 3 are installed between the frame plates 2. A carriage 4 is inserted into and supported by the guide member 3 so as to reciprocate in the axial direction of the guide member 3. The carriage 4 is connected to a carriage motor M1 (see FIG. 5) via a timing belt stretched around a pair of pulleys (not shown). As a result, the carriage 4 reciprocates in the main scanning direction (Y arrow direction and anti-Y arrow direction in the figure) along the guide member 3 by driving the carriage motor M1.

  A recording head 5 as a liquid ejecting head is mounted on the lower surface of the carriage 4. The recording head 5 includes a flow path forming member in which a flow path is formed, a piezoelectric element, a nozzle plate provided on the lower surface, and the like. Ink is supplied as a liquid from the ink supply mechanism 10 to the flow path in the recording head 5, and minute ink droplets are ejected from the nozzles perforated in the nozzle plate by driving the piezoelectric element. Yes.

  The printer 1 also includes a paper feeding mechanism (not shown) having a paper feeding motor M2 (see FIG. 5). The paper feeding mechanism is located below the recording head 5 in the sub-scanning direction (X arrow direction in the figure). Transports print media such as paper. An operation of ejecting ink droplets while the recording head 5 mounted on the carriage 4 reciprocates in the main scanning direction, and an operation of transporting paper in the sub-scanning direction below the recording head 5 by the paper feeding mechanism described above. Printing is performed by alternately repeating.

  Next, the ink supply mechanism 10 will be described. The ink supply mechanism 10 includes four cartridges 11 as main storage units, an ink flow path 15 for leading ink in the cartridges 11 to the recording head 5, four auxiliary storage units mounted on the carriage 4, and auxiliary units. And a sub tank 21 as a storage means.

  Each cartridge 11 stores cyan, magenta, yellow, and black ink, respectively. Each cartridge 11 is detachably attached to a cartridge holder 12 provided on the printer 1 main body side.

As shown in FIG. 2, the cartridge 11 accommodates an ink pack 14 as a storage part in a box-shaped case 13 made of synthetic resin or the like. The case 13 has a front wall portion 13a, a back wall portion 13b, an upper wall portion 13c, and a bottom wall portion 13d. A through-hole 13e for fixing the ink pack 14 is formed through the front wall portion 13a. ing. The ink pack 14 includes a bag portion 14a formed by welding a film F having a gas barrier property and formed into a bag shape, and a supply port 14b made of a synthetic resin with one end sandwiched in the bag portion 14a. Each bag portion 14a of each cartridge 11 is filled with degassed ink of four colors of cyan, magenta, yellow, and black. The supply port 14b has a flow path (not shown) therein, and is welded to the inside of the film F in a state where one end in the longitudinal direction is inserted into the bag portion 14a. The ink pack 14 is positioned with respect to the case 13 by fixing the supply port 14 b to the through hole 13 e of the case 13.

  As shown in FIG. 2, the cartridge holder 12 is arranged so that the cartridge 11 containing the ink pack 14 is placed so that the front wall portion 13 a of the case 13 is lower than the back wall portion 13 b in the vertical direction (Z arrow direction). It is configured to be installed diagonally. Thereby, the ink pack 14 in each cartridge 11 attached to the cartridge holder 12 is in an inclined posture in which a supply port 14b as a liquid supply port is disposed below. Accordingly, when air as a gas is mixed in the ink pack 14 as bubbles, for example, the portion of the ink pack 14 in the vertical direction, that is, the side of the bag portion 14a on the side where the supply port 14b is attached is opposite. It stays in the edge part 14c provided in the side as a storage part. As a result, bubbles mixed in the ink pack 14 are not discharged from the cartridge 11 to the recording head 5 side.

  Each cartridge holder 12 is provided with a hollow insertion needle (not shown), and an ink flow path 15 is connected to each insertion needle. As shown in FIG. 1, each ink flow path 15 is reciprocated between the carriage 4 and each pump-side flow path 16 in which first to fourth tube pumps 20 a to 20 d serving as pump means are disposed in the middle of the flow path. The pump side flow path 16 and the flexible tube 18 are connected by a joint 17.

  Each pump side flow path 16 is comprised from the flow path formed in the flow path formation member made from a synthetic resin, or a flexible tube, such as polyethylene. Further, the pump-side flow channel 16 guides cyan, magenta, yellow, and black inks to the flexible tube 18 respectively.

  The first to fourth tube pumps 20a to 20d include a flexible pump tube and a roller (not shown) such as an elastomer tube. The pump tubes of the first to fourth tube pumps 20a to 20d are connected to the pump-side flow path 16, respectively.

  Further, the pump motors M3a to M3d (see FIG. 5) included in the printer 1 are connected to the first to fourth tube pumps 20a to 20d, respectively. As the pump motors M3a to M3d rotate in the forward direction, the rollers of the tube pumps 20a to 20d rotate in the forward direction, so that the ink or air in the pump tube is moved downstream, that is, to the recording head 5 side. Send it out. When each of the pump motors M3a to M3d is reversely rotated, the roller rotates in the reverse direction, and the ink or air in the pump tube is sent to the upstream side, that is, the cartridge 11 side. The pump motors M3a to M3d are stepping motors or the like, and are provided, for example, one for each of the first to fourth tube pumps 20a to 20d. When the first to fourth tube pumps 20a to 20d and the pump motors M3a to M3d are described without being distinguished from each other, they are simply described as the tube pump 20 and the pump motor M3.

The flexible tube 18 constituting the ink flow path 15 is, for example, a converging flow path in which four flow paths are arranged in the direction of the Z arrow, and a polyethylene tube, a tube having an aluminum layer on a polyethylene tube, or the like, At least a part thereof is a tube made of a flexible material. The flexible tube 18 and the carriage 4 are connected via a connecting portion 19 so that the flexible tube 18 does not fall off due to the operation of the carriage 4. In addition, each flow path of the flexible tube 18 is connected to each sub tank 21 on the carriage 4 via a connecting portion 19. Each sub-tank 21 temporarily stores cyan, magenta, yellow, and black inks sent through the respective ink flow paths 15.

  With such a configuration, when each pump motor M3 rotates in the forward direction, each tube pump 20 rotates in the forward direction, and the fluid in the pump-side flow path 16 is pumped to the recording head 5 side. When the tube pump 20 further continues to rotate, the flow path upstream of the tube pump 20 (on the cartridge 11 side) is in a negative pressure state, and the ink in the cartridge 11 is led out to the pump-side flow path 16. As a result, the ink is pumped from the cartridge 11 to the sub tank 21 via the ink flow path 15.

  Further, when each pump motor M3 is reversely rotated, the air in each sub tank 21 mounted on the carriage 4 is discharged to the cartridge 11 through the ink flow path 15, whereby the air in the sub tank 21 is discharged. This prevents bubbles from being mixed into the ink in the sub tank 21. At this time, the air in the sub tank 21 is mixed in the ink pack 14 of the cartridge 11, but the air is stored in the end 14 c in the vertical direction of the ink pack 14 and led out from the supply port 14 b side. There is no such thing.

  Next, the sub tank 21 will be described with reference to FIGS. FIG. 3 is a side view for explaining the main part of the sub-tank 21, and FIG. 4 is a cross-sectional view of the main part of the sub-tank 21. As shown in FIG. 3, the sub tank 21 includes a plate-shaped flow path forming plate 23 made of synthetic resin in a box-shaped case 22 indicated by a chain line in the drawing. As shown in FIG. 4, a tubular inlet 24 is formed in the flow path forming plate 23 so as to protrude. The tube T communicating with the connecting portion 19 is inserted into the introduction port 24, whereby the ink in the ink flow path 15 is introduced into the flow path forming plate 23. A communication groove 25 that communicates with the flow path in the introduction port 24 is formed on the lower surface 23 b of the flow path forming plate 23. The communication groove 25 is sealed by a gas barrier film 26 stretched on the lower surface 23b of the flow path forming plate 23 by thermal welding or the like. The communication groove 25 communicates with a vertical pipe 27 that protrudes and is formed on the upper surface 23 a side of the flow path forming plate 23 as a liquid introduction part and a discharge part. The vertical pipe 27 has a flow path 27 a that communicates with the communication groove 25 therein, and extends from the flow path forming plate 23 in the direction of the arrow Z.

  Further, a substantially circular fitting portion 28 is formed so as to protrude from the upper surface 23 a of the flow path forming plate 23 and next to the vertical pipe 27. The fitting portion 28 is formed lower than the height of the vertical pipe 27, and an annular protrusion 29 is further formed on the upper surface 28a. A mortar-shaped inclined portion 30 is formed inside the annular protrusion 29. A filter 31 is provided inside the annular protrusion 29 and above the inclined portion 30. The filter 31 is formed in a substantially disk shape having substantially the same diameter as the inner diameter of the annular protrusion 29 and is fitted inside the annular protrusion 29. In addition, a head-side flow path 32 as a liquid lead-out portion communicating with the recording head 5 is formed through the bottom portion of the inclined portion 30 toward the back side of the paper surface. The head-side flow path 32 is formed in a groove shape on the lower surface 23b of the flow path forming plate 23, and is sealed with a film 26 welded to the lower surface 23b to form a flow path.

  In addition, a regulating member 33 as a substantially U-shaped regulating means is fastened to the upper surface 23 a of the flow path forming plate 23 by each bolt 34. The restricting member 33 includes a bolt fastening portion 35, a vertical portion 36, and a horizontal portion 37 formed at the proximal end. A protruding portion 38 protruding in the anti-Z arrow direction is formed at the approximate center of the horizontal portion 37.

Further, between the regulating member 33 and the flow path forming plate 23, an expandable member 40 as a variable volume portion is provided. The elastic member 40 is made of a flexible synthetic resin formed in a covered cylinder shape, and its side wall is formed in a bellows shape. As shown in FIG. 4, a fitting protrusion 42 is formed to protrude from the upper portion of the elastic member 40. Further, a plate-like contact portion 43 is provided at the tip of the fitting projection 42. The fitting protrusion 42 is fitted with a detection plate 44 that is formed larger than the upper surface of the elastic member 40. In a state where the detection plate 44 is fixed to the fitting protrusion 42, the contact portion 43 at the tip of the fitting protrusion 42 protrudes from the detection plate 44.

  Further, the lower opening 40a of the expansion / contraction member 40 is formed to have the same size as the outer diameter of the fitting portion 28 of the flow path forming plate 23, and the lower opening 40a is fitted to the fitting portion 28. The elastic member 40 and the flow path forming plate 23 are connected. Further, when the lower opening 40a is fitted into the fitting portion 28, the vertical pipe 27 and the filter 31 of the flow path forming plate 23 are contained inside the elastic member 40, and the contact portion 43 of the elastic member 40 is It will be in the state contact | abutted to the protrusion part 38 of the control member 33. FIG.

  A storage chamber 41 for temporarily storing ink is formed by the side wall and upper wall of the elastic member 40 and the flow path forming plate 23. The opening 27b of the vertical pipe 27 is disposed at a higher position in the vertical direction (Z arrow direction) than the upper surface 23a of the flow path forming plate 23, which is the bottom surface of the storage chamber 41.

  A biasing spring 46 as a biasing means is disposed between the upper surface 23 a of the flow path forming plate 23 and the lower surface 44 b of the detection plate 44. The urging spring 46 urges the detection plate 44 in the Z arrow direction, and urges the expansion / contraction member 40 in a direction in which the storage chamber 41 expands.

  The vertical portion 36 of the restricting member 33 is provided with a first switch 36a and a second switch 36b, which are limit switches and constitute detection means. The first switch 36a is provided below the second switch 36b in the vertical direction.

  When each of the tube pumps 20 is driven, the expansion / contraction member 40 expands and contracts, and when the contact portion 45 contacts the first switch 36a or the second switch 36b, the first switch 36a or the second switch 36b outputs an ON signal. The position of the detection plate 44, that is, the expansion / contraction state of the expansion / contraction member 40 is detected. In the initial state where the assembly of the sub tank 21 is completed, the contact portion 45 is in a state of being in contact with the second switch 36b. In the initial state, the contact portion 43 of the expansion / contraction member 40 is in contact with the protruding portion 38 of the restriction member 33, and the expansion of the expansion / contraction member 40 in the Z direction is restricted.

  Further, an urging spring 46 as an urging means is interposed between the upper surface 23 a of the flow path forming plate 23 and the lower surface 44 b of the detection plate 44. The urging spring 46 presses the detection plate 44 in the Z arrow direction, and urges the expansion / contraction member 40 in a direction in which the volume of the storage chamber 41 increases.

  When the tube pump 20 is rotated forward to the sub tank 21 configured as described above, and the ink is sent from the cartridge 11 through the ink flow path 15, the inlet 24 and the communication groove of the flow path forming plate 23. 25. Ink is supplied to the storage chamber 41 of the extendable member 40 via the flow path 27a in the vertical pipe 27. When the tube pump 20 is rotationally driven for a predetermined time, a predetermined amount of ink is stored in the storage chamber 41. The ink temporarily stored in the storage chamber 41 is temporarily stored in the storage chamber 41, filtered by the filter 31, and supplied to the recording head 5 through the inclined portion 30 and the head-side flow path 32.

  After the tube pump 20 is stopped, when ink droplets are ejected from the recording head 5 by the printing operation of the printer 1 and the ink in the recording head 5 is consumed, the ink stored in the storage chamber 41 is applied to the recording head 5. Supplied. When the ink in the storage chamber 41 is consumed, the internal pressure of the storage chamber 41 decreases, and the elastic member 40 contracts in the anti-Z arrow direction against the urging force of the urging spring 46. At this time, when the tube pump 20 rotates forward again, ink is supplied from the cartridge 11 to the storage chamber 41, and the amount of ink in the storage chamber 41 increases. And as the internal pressure of the storage chamber 41 rises, the elastic member 40 extends in the Z arrow direction.

  Next, the configuration of the controller 1a of the printer 1 will be described with reference to FIG. The controller 1a includes a CPU 50 that performs main control, a RAM 51, a ROM 52, an ASIC 53, a timer 54, and a detection unit 55 that constitutes detection means. The CPU 50 operates in accordance with a control program stored in the ROM 52. The first motor drive circuit 56 drives and controls the carriage motor M1, the second motor drive circuit 57 drives and controls the paper feed motor M2, and the third drives and controls the pump motor M3. Various drive signals are output to the motor drive circuit 58. In addition, the head drive circuit 59 that drives and controls the recording head 5 and the display drive circuit 60 that displays various images on the display 61 provided in the outer case (not shown) of the printer 1 are driven and controlled. Further, the ASIC 53 performs bitmap conversion on image data input from the outside by the printer 1 and performs image processing such as binarization. The timer 54 measures an elapsed time from the time when the sub tank 21 is filled with ink. The detection unit 55 detects an ON signal from the first switch 36 a and the second switch 36 b and outputs a detection signal to the CPU 50.

  Next, the processing procedure of this embodiment is demonstrated according to FIGS. First, a processing procedure in an initial state in which the ink flow path 15 and the recording head 5 are not filled with ink, such as when the printer 1 is used, will be described with reference to FIG. After the cartridge 11 is mounted, the CPU 50 of the controller 1a drives and controls the third motor drive circuit 58 to rotate each pump motor M3 in the forward direction and forwardly rotate each tube pump 20 (step S1-1). ). When each pump motor M3 starts to rotate, the timer 54 measures an elapsed time from the start time (hereinafter, motor forward rotation time).

  When each pump motor M3 rotates in the forward direction, each roller of each tube pump 20 rotates in the forward direction, and the pump tube is squeezed so that the internal air (or the ink flow into the initial state of the printer 1) can be obtained. The cleaning liquid filled in the passage 15) is pumped downstream. As a result, a negative pressure is generated in each pump-side channel 16 upstream of each tube pump 20, and ink in each cartridge 11 is led to the pump-side channel 16. Then, when each tube pump 20 further rotates forward, the ink flows into the sub tank 21 via each ink flow path 15.

  In the initial state, as shown in FIG. 4, each of the sub tanks 21 has a contact portion 43 of each elastic member 40 abutting a protrusion 38 of the regulating member 33 and a contact portion 45 of each detection plate 44. The second switch 36b of each regulating member 33 is in contact with the second switch 36b. When ink flows into the introduction port 24 of the sub tank 21, the ink I flows into the flow path 27a in the vertical tube 27 through the communication groove 25 as shown in FIG. Then, the ink I overflows from the opening 27 b of the vertical pipe 27 and flows into each storage chamber 41. The ink I led into each storage chamber 41 is filtered by the filter 31 and supplied to the recording head 5 via the inclined portion 30 and the head-side flow path 32.

  As each tube pump 20 continues to rotate, the ink I accumulates in the storage chamber 41 as shown in FIG. 9, and the liquid level rises. As a result, the internal pressure in each storage chamber 41 rises, and the expansion / contraction member 40 tends to extend in the direction of the arrow Z. The extension beyond the initial state is regulated.

  Further, as shown in FIG. 6, the CPU 50 determines whether or not the motor forward rotation time counted by the timer 54 has exceeded a predetermined time T1 (step S1-2). During this predetermined time T1, the ink I accumulates in each storage chamber 41 to such an extent that the ink I does not leak from the recording head 5 due to the increase in internal pressure of each storage chamber 41 when each pump motor M3 is driven at a predetermined rotation speed. It is time until. When the predetermined time T1 has elapsed, the liquid level of the ink I stored in each storage chamber 41 is below the opening 27b of the vertical tube 27.

  If it is determined that the predetermined time T1 has elapsed (YES in step S1-2), the CPU 50 reversely rotates the pump motor M3 via the third motor drive circuit 58 (step S1-3). When the pump motor M3 rotates in the reverse direction, each tube pump 20 rotates in the opposite direction, and the roller of each tube pump 20 rotates while squeezing the pump tube from the downstream side to the upstream side. As a result, a negative pressure is generated in the pump-side flow path 16 on the downstream side (recording head side 5) from each tube pump 20, and is above the liquid level of the ink I in the storage chamber 41 shown in FIG. The accommodated air is discharged into each flexible tube 18 through the vertical pipe 27. At this time, since the air discharge amount due to the reduction of the expansion / contraction member 40 is larger than the volume in the flexible tube 18 and the pump side flow path 16, the air discharged to the flexible tube 18 is pump side flow path 16. The ink is discharged into the ink pack 14 of the cartridge 11 through the tube pump 20. At this time, air flows in through the supply port 14b of each ink pack 14, and is stored in the end portion 14c of the bag portion 14a.

  When the tube pump 20 is further reversed and the air in the storage chamber 41 is discharged, the internal pressure of the expansion / contraction member 40 decreases, and the expansion / contraction member 40 resists the urging force of the urging spring 46. Shrink toward the side (counter-Z arrow direction). As a result, the detection plate 44 is displaced to the flow path forming plate 23 side, and the contact portion 45 of the detection plate 44 that has been in contact with each second switch 36b is separated from the second switch 36b. Then, as the expansion / contraction members 40 are reduced, the detection plate 44 descends toward the first switch 36a.

  The CPU 50 determines whether or not the contact portion 45 of each detection plate 44 has contacted each first switch 36a (step S1-4). When the ON signal is not output from the first switch 36a (NO in step S1-4), the reverse rotation of the tube pump 20 is continued (step S1-3).

  As the gas in the storage chamber 41 decreases, as shown in FIG. 10, when each of the telescopic members 40 contracts and the contact portion 45 of each detection plate 44 comes into contact with the first switch 36a, the first switch 36a turns on. A signal is output (hereinafter, the state of the expandable member 40 at this time is referred to as a maximum contracted state). Further, as described above, the elastic member 40 in the maximum contracted state receives a biasing force in the direction in which the storage chamber 41 expands by the biasing spring 46. For this reason, the storage chamber 41 at this time is in a negative pressure state.

  If the contact part 45 and the 1st switch 36a contact, the detection part 55 of the controller 1a will input the ON signal of the 1st switch 36a, and will output a detection signal to CPU50. Based on this, the CPU 50 determines that the contact portion 45 has contacted the first switch 36a (YES in step S1-4), and rotates each pump motor M3 in the forward direction (step S1-5).

  When each pump motor M3 is rotated in the positive direction, the ink I is supplied from each cartridge 11 toward each sub tank 21 by the negative pressure generated in each storage chamber 41 and the pressure due to the normal rotation of the tube pump 20. When the ink I flows into the expansion / contraction member 40 in the maximum contraction state, each expansion / contraction member 40 expands, and with the expansion of the expansion / contraction member 40, each detection plate 44 moves away from the first switch 36a and the second switch 36b. Displace towards

  Subsequently, the CPU 50 determines whether or not the contact portion 45 of each detection plate 44 has contacted each second switch 36b (step S1-6). When the contact portion 45 of the detection plate 44 is positioned between the first switch 36a and the second switch 36b, the ON signal is not output from the second switch 36b (NO in step S1-6), so the pump motor M3 The rotation in the positive direction is continued (step S1-5).

  When the ink I in each storage chamber 41 increases, as shown in FIG. 11, each elastic member 40 extends, and the contact portion 45 of each detection plate 44 comes into contact with the second switch 36b. At this time, the contact portions 43 of the respective elastic members 40 are not in contact with the protruding portions 38 of the respective regulating members 33 (hereinafter, this state of the elastic members 40 is referred to as a maximum extended state). When the telescopic member 40 reaches the maximum extension state for the first time, the liquid level of the ink I in each storage chamber 41 is lower than the opening 27 b of the vertical tube 27. When each contact portion 45 and each second switch 36b come into contact and an ON signal is output from the second switch 36b, the CPU 50 determines that the contact portion 45 and the second switch 36b have come into contact (step S1). YES at -6), the process proceeds to step S1-7.

  In step S <b> 1-7, the CPU 50 adds “1” to the counter value Ca of the expansion / contraction counter stored in the RAM 51 and updates it. This counter is a counter that counts the number of times that the expansion / contraction member 40 has reached the maximum extension state, and its initial value is “0”. Then, the CPU 50 determines whether or not the counter value Ca has reached the predetermined number N1 (step S1-8). The predetermined number of times N1 is set to the number of times that the expansion and contraction member 40 expands until the ink I in the storage chamber 41 reaches the maximum amount, which is obtained in advance through experiments. In the present embodiment, the predetermined number of times is set to “2” times.

  If it is determined that the counter value Ca does not exceed the predetermined number N1 (NO in step S1-8), the process returns to step S1-3, and the CPU 50 reverses each pump motor M3 via the third motor drive circuit 58. Rotate. As a result, each tube pump 20 rotates in the reverse direction, and the air staying above the liquid level is sucked through the opening 27b above the liquid level of the ink I in the vertical direction (Z arrow direction). Air sucked from each opening 27b is pumped to each cartridge 11 via each ink flow path 15. At this time, when the ink level is almost the same as the opening 27b, a small amount of ink I may be sucked from the opening 27b, but the sucked ink I is sent to each cartridge 11 together with air. The air pumped to each ink pack 14 is stored in the end portion 14 c of the ink pack 14, and the ink I is stored together with the ink I in the ink pack 14. That is, the ink I sucked from the sub tank 21 when the air is discharged is also stored in each ink pack 14 and reused, so that it is not discarded. When the air in the storage chamber 41 decreases in this way, as shown in FIG. 12, the respective elastic members 40 are contracted, and the contact portions 45 of the respective detection plates 44 are in contact with the first switches 36a.

  When CPU 50 determines that each contact portion 45 has contacted first switch 36a (YES in step S1-4), CPU 50 rotates each pump motor M3 in the forward direction and forwards each tube pump 20 (step S1- 5). As a result, the ink I is pumped from each cartridge 11 to each sub tank 21 through each ink flow path 15. Thereby, the ink I in each storage chamber 41 further increases.

  As the ink I in each storage chamber 41 increases, the liquid level of the ink I becomes higher than the opening 27 b of the vertical tube 27. Further, as the internal pressure rises, the elastic member 40 expands, and as shown in FIG. 13, the contact portion 45 of the detection plate 44 contacts the second switch 36b. At this time, the ink I in the storage chamber 41 is the maximum amount.

  If the contact part 45 and the 2nd switch 36b contact, the 2nd switch 36b will output an ON signal to the detection part 55 of the controller 1a. The CPU 50 determines that the contact portion 45 has contacted the second switch 36b (YES in step S1-6), and updates the counter value Ca of the expansion / contraction number counter (step S1-7).

When CPU 50 determines that counter value Ca has reached the predetermined number of times “2” (YES in step S1-8), it resets counter value Ca (step S1-9).
Then, the ink filling process from the initial state is finished.

  After filling the sub tank 21 with the ink I in this way, the printer 1 performs a printing operation. As described above, the printer 1 alternately performs the paper feeding operation and the printing operation, and ink droplets are ejected from the nozzles of the recording head 5. In the present embodiment, the CPU 50 controls the pump motors M3a to M3d separately based on detection signals from the sub tanks 21 and the like.

  When the ink I in the storage chamber 41 is consumed by the printing operation, the internal pressure of the storage chamber 41 decreases, and the elastic member 40 moves toward the flow path forming plate 23 against the biasing force of the biasing spring 46. Shrink. As a result, as shown in FIG. 14, the detection plate 44 is also lowered toward the flow path forming plate 23, and the contact portion 45 of the detection plate 44 is gradually separated from the second switch 36b and gradually moved to the first switch 36a. approach.

  As shown in FIG. 7, during the printing operation, the CPU 50 waits for the contact portion 45 to contact the first switch 36a (step S2-1). Then, when the ink I in the storage chamber 41 is further consumed and the elastic member 40 is in the maximum contracted state as shown in FIG. 10, the contact portion 45 contacts the first switch 36a. Further, the storage chamber 41 is in a negative pressure state by the biasing force of the biasing spring 46. At this time, the liquid level of the ink I in the storage chamber 41 is higher than the filter 31, and the filter 31 is not exposed to air.

  When the CPU 50 receives an ON signal from the first switch 36a included in one sub tank 21, the CPU 50 determines that the contact portion 45 of the sub tank 21 has contacted the first switch 36a (YES in step S2-1), and turns on the signal. The pump motor M3 corresponding to the sub-tank 21 that outputs is rotated in the forward direction to rotate the tube pump 20 forward (step S2-2). As a result, the ink I is sent from the cartridge 11 to the sub tank 21 due to the forward rotation of the tube pump 20 and the negative pressure generated in the storage chamber 41. At this time, the elastic member 40 expands as the internal pressure of the storage chamber 41 increases.

  Subsequently, the CPU 50 controls the timer 54 to measure the normal rotation time of the tube pump 20 (step S2-3). And it waits for the contact part 45 of the detection board 44 to contact the 2nd switch 36b (step S2-4). When the contact part 45 does not contact the second switch 36b (NO in step S2-4), the CPU 50 determines whether or not the forward rotation time measured by the timer 54 has exceeded the predetermined time T2 (step S2-5). ). This predetermined time T2 is from the time when the ink I in the storage chamber 41 is consumed and the expansion / contraction member 40 reaches the maximum contraction state until the expansion / contraction member 40 reaches the maximum extension state by the normal rotation of the tube pump 20. Is the time obtained by experiment.

  When the normal rotation time is within the predetermined time T2 (NO in step S2-5), the process returns to step S2-2, and the tube pump 20 is normally rotated until the normal rotation time exceeds the predetermined time T2. If it is determined that the forward rotation time has exceeded the predetermined time T2 (YES in step S2-5), the CPU 50 does not reach the maximum extension state even when the tube pump 20 is rotated forward. (Liquid consumption state) is detected (step S2-6). At this time, the CPU 50 controls the display drive circuit 60 and outputs the ink end display of the cartridge 11 to the display 61.

On the other hand, when the tube pump 20 rotates forward, the CPU 50 inputs a detection signal via the detection unit 55 and determines that the contact portion 45 of the detection plate 44 has contacted the second switch 36b (in step S2-4). YES), the pump motor M3 is controlled, and the tube pump 20 is stopped (step S2-7). At this time, the ink I in the storage chamber 41 is in an increased state.

  As described above, the ink I temporarily stored in the storage chamber 41 may be mixed with air that has flowed into the ink flow path 15 when the cartridge 11 is attached or detached, air that has permeated through the side wall of the expansion / contraction member 40, or the like. That is, each member such as the elastic member 40 has a gas barrier property, but there is a slight amount of air permeation and a minute amount of air from the joint of each member. The air mixed in the ink I stays above the liquid surface of the ink I while being stored in the storage chamber 41. When a long period of time elapses, the occupied volume of air in the storage chamber 41 increases and the telescopic member 40 expands. As described above, when the occupied volume of air increases, the amount of ink I stored decreases, and the ink I cannot be ejected. For this reason, it is necessary to perform an air discharge operation for discharging the air in the storage chamber 41 every predetermined period.

  This air discharge operation will be described with reference to FIG. First, the CPU 50 controls the timer 54 to start measuring the elapsed time from the time when ink is initially filled from the initial state or the time when the previous air discharge operation is completed for each sub tank 21 ( Step S3-1). Then, it is determined whether or not the time measured by the timer 54 has passed a predetermined time T3 (maximum required time) (step S3-2). The predetermined time T3 is a time obtained by an experiment or the like in advance for the time during which the air is accumulated in the storage chamber 41 from the time when the ink is first filled from the initial state or the time when the previous air discharge operation is completed.

  If it is determined that the predetermined time T3 has elapsed (YES in step S3-2), the pump motor M3 corresponding to the sub tank 21 for which the predetermined time T3 has elapsed is rotated in the forward direction to cause the tube pump 20 to rotate forward (step S3- 3). As a result, the ink I is pumped from the cartridge 11 to the sub tank 21. When the pump motor M3 is rotated forward, the CPU 50 resets the elapsed time counted by the timer 54. When the pump motor M3 is rotated in the forward direction, the CPU 50 controls the timer 54 and starts measuring the forward rotation time of the tube pump 20 (step S3-4).

  Next, the CPU 50 determines whether or not the contact portion 45 of the detection plate 44 of the sub tank 21 has contacted the second switch 36b (step S3-5). When contact portion 45 and second switch 36b are not in contact (NO in step S3-5), whether or not the normal rotation time measured by timer 54 has exceeded a predetermined time T2 for detecting the ink end Is determined (step S3-6). If the predetermined time T2 has not been exceeded (NO in step S3-6), the process returns to step S3-5. If the predetermined time T2 has been exceeded (YES in step S3-6), an ink end is detected (step S3-7), and the process ends, as in step S2-6 described above.

  In step S3-5, as shown in FIG. 9, when it is determined that the contact portion 45 has contacted the second switch 36b (YES in step S3-5), the CPU 50 rotates the pump motor M3 in the reverse direction, The tube pump 20 is reversely rotated (step S3-8). As a result, as shown in FIG. 9, the air accumulated in the storage chamber 41 of the sub tank 21 is sucked into the opening 27 b of the vertical pipe 27 and discharged to the corresponding cartridge 11 side. The air that has flowed into the cartridge 11 stays at the end 14 c of the ink pack 14.

Next, the CPU 50 determines whether or not the contact portion 45 of the detection plate 44 has contacted the first switch 36a (step S3-9). If the contact portion 45 is not in contact with the first switch 36a (NO in step S3-9), the process returns to step S3-8, and the pump motor M3 continues to rotate in the reverse direction. If it is determined that the contact portion 45 has contacted the first switch 36a (YES in step S3-9), "1" is added to the counter value Cb of the expansion / contraction counter corresponding to the sub tank 21 stored in the RAM 51. Update (step S3
-10).

  Then, the CPU 50 determines whether or not the counter value Cb has reached the predetermined number N2 (step S3-10). The predetermined number of times N2 is the number of times that the expansion / contraction number of the expansion / contraction member 40 required for exhausting the air in the storage chamber 41 when the predetermined time T3 has elapsed is obtained in advance through experiments. When the counter value Cb has not reached the predetermined number of times N2, the process returns to step S3-3, and the air discharge by the reduction of the expansion member 40 and the supply of the ink I by the extension are repeated until the counter value Cb reaches the predetermined number N2. When counter value Cb reaches N2 a predetermined number of times (YES in step S3-10), the air discharge operation is terminated.

  (1) In the above embodiment, the ink I is supplied from the cartridge 11 to the recording head 5 in the middle of the ink flow path 15 connecting the cartridge 11 and the recording head 5, and in the sub tank 21 directly above the recording head 5. A tube pump 20 for returning the staying air to the cartridge 11 is provided. For this reason, by discharging the air staying in the sub tank 21, it is possible to prevent bubbles from entering the ink I supplied to the recording head 5, thereby preventing ejection failure (printing failure). Further, since the air in the sub tank 21 is discharged to the cartridge 11, even if a part of the ink I stored in the sub tank 21 is discharged during the air discharging operation, the discharged ink I is stored in the cartridge 11. can do. Therefore, the ink I discharged from the sub tank 21 can be reused as the printing ink I. For this reason, the ink discard rate can be reduced.

  (2) In the above embodiment, the ink pack 14 in the cartridge 11 is inclined so that the supply port 14b is vertically lower than the bag portion 14a. For this reason, the air discharged from the sub tank 21 is stored in the end portion 14c of the ink pack 14 of the cartridge 11 that is positioned vertically above the supply port 14b. For this reason, the air stored in the cartridge 11 is not sent back from the supply port 14b to the sub tank 21 and the recording head 5 side.

  (3) In the above embodiment, the sub tank 21 communicates with the tube pump 20, and the expansion / contraction member 40 whose internal volume can be changed, and the air I stayed in the expansion / contraction member 40 while introducing the ink I into the expansion / contraction member 40. And a vertical pipe 27 for discharging the cartridge 11 to the cartridge 11. Further, the elastic member 40 is urged by the urging spring 46 in the direction in which the storage chamber 41 (internal volume) expands. When the expansion / contraction member 40 is contracted, the ink I is introduced from the cartridge 11 by the urging force of the urging spring 46 and the drive of the tube pump 20. For this reason, a relatively large amount of ink I can be stored in the sub tank 21 in a short time.

  (4) In the above embodiment, the opening 27 b of the vertical pipe 27 is arranged at a higher position in the vertical direction (Z arrow direction) than the upper surface 23 a of the flow path forming plate 23, which is the bottom surface of the storage chamber 41. That is, a space for filling the ink I was maintained between the inner bottom surface of the elastic member 40 (storage chamber 41) and the opening 27b. For this reason, since the air staying on the liquid surface can be discharged from the opening 27b in a state where a predetermined amount of ink I is held in the elastic member 40, the air staying in the sub tank 21 is efficiently used. Can discharge well.

(5) In the above embodiment, the contact portion 45 of the detection plate 44 is in contact with the first switch 36a when the storage chamber 41 of the expansion / contraction member 40 has the minimum volume (maximum contraction state). In addition, the storage chamber 41 of the expansion / contraction member 40 is in contact with the second switch 36b in the maximum volume (maximum extended state). Further, when the first and second switches 36a and 36b are in contact with the detection plate 44, an ON signal is output to the detection unit 55 of the controller 1a. For this reason, the amount of ink I in the storage chamber 41 can be managed by controlling the expansion / contraction operation of the expansion / contraction member 40.

  (6) In the above embodiment, the protrusion 38 of the restricting member 33 restricts the expansion of the elastic member 40 beyond the maximum extension state. For this reason, it is possible to prevent occurrence of an event in which the expansion / contraction member 40 is damaged or the expansion / contraction member 40 is extended and the reduction operation cannot be performed.

  (7) In the above embodiment, the ink supply operation to the sub tank 21 by the normal rotation of the tube pump 20 and the air discharge operation to discharge the air in the sub tank 21 are alternately repeated to fill the sub tank 21 with the ink I. To do. For this reason, it is possible to fill the ink I while preventing bubbles from being mixed into the ink I in the sub tank 21.

  (8) In the above embodiment, the air discharge operation and the liquid supply operation are performed every predetermined time T3 so that the air in the sub tank 21 is removed. For this reason, before air (bubbles) accumulates and the remaining amount of ink I becomes small, air can be discharged and ink I can be filled.

  (9) In the above embodiment, the ink supply operation is performed when the ink I in the sub tank 21 is consumed by the printing operation and the contact portion 45 of the detection plate 44 comes into contact with the first switch 36a. For this reason, a certain amount or more of ink I can always be stored in the sub tank 21.

  (10) In the above embodiment, if the contact portion 45 of the detection plate 44 does not contact the second switch 36b even after the ink supply operation is performed and the predetermined time T2 has elapsed, the ink end of the cartridge 11 is detected. I made it. Therefore, the ink end of the cartridge 11 can be detected with a simple configuration and control.

In addition, you may change the said embodiment as follows.
In the above embodiment, during the printing operation and the air venting operation, the CPU 50 controls the pump motors M3a to M3d separately based on the detection signals from the sub-tanks 21. Also good.

In the above embodiment, the tube pump 20 is provided separately for each ink flow path 15, but one pump may be used as a common drive source.
In the above embodiment, when the ink I is consumed by printing, the amount of the ink I in the storage chamber 41 is increased by rotating the tube pump 20 forward. However, the tube pump 20 rotates forward and reversely. The ink I may be supplied into the storage chamber 41 by repeating the above.

The flexible tube 18 is a converging channel, but may be other than this.
In the above-described embodiment, the elastic member 40 whose side wall is formed in a bellows shape is used as the variable volume portion, but any member that can expand and contract in the vertical direction may be used.

  In the above embodiment, the cartridge 11 is a cartridge provided with the ink pack 14, but it may be a cartridge in which a film is welded to the opening of the case and the ink is stored in a space defined by the inner surface of the case and the film. In this case, the supply port formed in the case may be disposed vertically below the storage space.

In the above embodiment, the auxiliary storage means is embodied in the sub tank 21 mounted above the recording head 5, but may be provided in other flow paths.
The liquid ejecting apparatus is not limited to the printer 1. For example, the liquid ejecting apparatus is a color filter manufacturing apparatus such as a liquid crystal display, an electrode forming apparatus such as an organic EL display or FED (surface emitting display), an ejecting apparatus that ejects bioorganic matter for biochip manufacturing, and a manufacturing for precision pipettes. An apparatus etc. may be sufficient.

FIG. 2 is a plan view of the printer according to the embodiment. The principal part sectional view of a cartridge. The principal part side view of a sub tank. Sectional drawing of the principal part of the subtank. The block diagram of the controller of a printer. Explanatory drawing of the process sequence of this embodiment. Explanatory drawing of the process sequence of this embodiment. Explanatory drawing of the process sequence of this embodiment. Sectional drawing of the principal part of the subtank. Sectional drawing of the principal part of the subtank. Sectional drawing of the principal part of the subtank. Sectional drawing of the principal part of the subtank. Sectional drawing of the principal part of the subtank. Sectional drawing of the principal part of the subtank.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Printer as a liquid ejecting apparatus, 5 ... Recording head as a liquid ejecting head, 11 ... Cartridge as main storage means, 14 ... Ink pack as storage part, 14b ... Supply port as liquid supply port, 15 ... Flow Ink flow path as path, 20 ... Tube pump as pump means, 21 ... Sub tank as auxiliary storage means, 27 ... Vertical pipe as liquid introduction part and discharge part, 27a ... Flow path, 27b ... Opening, 32 ... Liquid Head-side flow path as lead-out part, 33... Restricting member as restricting means, 36 a, 36 b... First and second switches constituting detecting means, 38... Projecting part as restricting means, 40. Telescopic members, 45 ... contact portions constituting detection means, 46 ... biasing springs as biasing means, 55 ... detection portions constituting detection means, I ... ink as liquid, 3 ... predetermined period of time as the maximum required time.

Claims (13)

A liquid jet head for discharging liquid;
Main storage means for storing liquid;
A flow path for supplying the liquid stored in the main storage means to the liquid jet head;
A liquid ejecting apparatus comprising auxiliary storage means for temporarily storing the liquid supplied from the main storage means,
A pump unit is provided that supplies the liquid in the main storage unit to the ejection head through the flow path, and sends out the gas retained in the auxiliary storage unit to the main storage unit through the channel. A liquid ejecting apparatus. The liquid ejecting apparatus according to claim 1,
The main storage means is
A reservoir for storing liquid;
A liquid supply port for leading the liquid to the auxiliary storage means side;
A liquid ejecting apparatus comprising: a storage unit that is positioned vertically above the liquid supply port and stores gas discharged from the auxiliary storage unit. The liquid ejecting apparatus according to claim 1 or 2,
The auxiliary storage means is
A variable volume portion communicating with the pump means and capable of changing an internal volume and biased in a direction in which the volume expands;
A liquid introduction section for introducing the liquid supplied from the main storage means into the variable volume section;
A discharge part for discharging the gas retained in the variable volume part to the main storage means side;
A liquid outlet for supplying liquid to the ejection head;
By driving the pump means, the gas of the variable volume part is discharged to the main storage means side, and the internal volume of the variable volume part is reduced,
A liquid ejecting apparatus, wherein the liquid is introduced into the variable volume portion from the main storage means side by the reduced urging force of the variable volume portion and the driving of the pump means. The liquid ejecting apparatus according to claim 3,
The liquid ejecting apparatus according to claim 1, wherein the variable volume portion includes a biasing unit that biases the internal volume in a direction in which the internal volume increases. The liquid ejecting apparatus according to claim 3 or 4,
The discharge part for discharging the gas in the variable volume part and the liquid introduction part for introducing a liquid into the variable volume part are integrated,
An opening for discharging gas and introducing liquid is provided at a position where a space for filling liquid is held between the inner bottom surface of the variable volume portion and the opening. The liquid ejecting apparatus according to any one of claims 3 to 5,
The variable volume portion has an elastic member that expands and contracts in a predetermined direction,
The liquid ejecting apparatus according to claim 1, further comprising detection means for detecting a maximum volume and a minimum volume of the expandable member. The liquid ejecting apparatus according to claim 6,
The detection means includes a first switch that contacts a part of the expansion / contraction member when the internal volume of the expansion / contraction member is a minimum volume, and a first switch that contacts the part of the expansion / contraction member when the internal volume of the expansion / contraction member is a maximum volume. A liquid ejecting apparatus comprising: a second switch in contact with the unit. The liquid ejecting apparatus according to any one of claims 3 to 7,
The liquid ejecting apparatus according to claim 1, further comprising a regulating unit configured to abut against the variable volume part and regulate further expansion of the internal volume when the internal volume of the variable volume part reaches an upper limit value. The liquid ejecting apparatus according to any one of claims 1 to 8,
A liquid supply operation for supplying liquid to the auxiliary storage means by driving the pump means in one direction;
By alternately driving a gas discharge operation for discharging the gas of the auxiliary storage means to the main storage means by driving the pump means in the other direction, the auxiliary storage means is filled with liquid. Liquid ejecting device. The liquid ejecting apparatus according to claim 9, wherein
The liquid ejecting apparatus according to claim 1, wherein the gas is discharged from the auxiliary storage unit by performing the gas discharge operation and the liquid supply operation every predetermined period. The liquid ejecting apparatus according to claim 6, wherein
Liquid is ejected by the ejection head, and when the detection means detects the minimum volume of the variable volume portion, the pump means is driven in one direction to supply liquid to the auxiliary storage means. A liquid ejecting apparatus. The liquid ejecting apparatus according to any one of claims 6 to 11,
The maximum volume of the variable volume portion is not detected by the detection means even if the elapsed time for performing the liquid supply operation for supplying the liquid to the auxiliary storage means by driving the pump means in one direction exceeds the maximum required time. In this case, a liquid ejecting apparatus that detects a liquid consumption state of the main storage means. A variable volume portion that can change the internal volume and is urged in a direction in which the volume expands;
A liquid introduction part for introducing liquid supplied from the outside into the variable volume part;
A discharge part for discharging the gas retained in the variable volume part to the outside;
A liquid outlet for supplying liquid to the outside,
As the gas in the variable volume part is discharged, the internal volume of the variable volume part decreases,
Auxiliary storage means for introducing liquid into the variable volume part from the outside by a negative pressure based on the biasing force of the reduced variable volume part.

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