JP4285159B2 - Tube pump and liquid injection device - Google Patents

Description

  The present invention relates to a tube pump and a liquid ejecting apparatus.

  2. Description of the Related Art Inkjet recording apparatuses are widely used as liquid ejecting apparatuses that eject liquid onto a target via a liquid ejecting head. In such an ink jet recording apparatus, ink may thicken near the nozzle of the recording head as a liquid ejecting head, or air bubbles may be mixed in the nozzle, and printing may not be performed satisfactorily. was there. In order to avoid these phenomena, many devices having a head cleaning mechanism have been proposed.

  As such a head cleaning mechanism, the nozzle of the recording head is covered with a cap, a pump provided in an ink discharge path communicating with the cap is driven, and pressure (negative pressure) generated by the pump is used. It has been known that ink is sucked from a nozzle.

  As an example of the pump, a tube pump 121 as shown in FIG. 16 has been known. The tube pump 121 includes a flexible tube 125 provided in an arc shape along the casing 123, a roller 127 that pressurizes the flexible tube 125, and a rotating body 129 that supports the roller 127. It was. That is, the flexible tube 125 is disposed along the inner wall of the casing 123 over almost a half circumference of the casing 123. Then, by rotating the rotating body 129, the roller 127 moves while sequentially crushing the flexible tube 125, whereby the inside of the flexible tube 125 on the upstream side of the portion housed in the casing 123. Was to be depressurized.

  In addition, this tube pump 121 repeats the state where the roller 127 crushes or does not crush the flexible tube 125 as the rotating body 129 rotates when there is only one roller 127. It was like that. Therefore, when the flexible tube 125 is not crushed by the roller 127, there is a possibility that the upstream and the downstream are in communication and the negative pressure accumulated on the upstream side disappears. As a result, the pressure formation is intermittent and difficult to accumulate, and there is a possibility that an appropriate negative pressure cannot be generated in the cap or noise may be generated.

  Therefore, as shown in FIG. 17, the rotating body 129 is provided with two or more rollers 127, and when the rotating body 129 is rotating, at least one of the rollers 127 always holds the flexible tube 125. Some were able to accumulate negative pressure by crushing. However, by providing two or more rollers 127, there is a problem that the apparatus becomes complicated and costs increase, such as providing a plurality of grooves 131 for supporting the rollers 127 on the rotating body 129, respectively. Further, the provision of the plurality of rollers 127 causes an increase in weight and the like, and there is a problem that energy for driving the rotating body 129 increases.

Therefore, as shown in FIG. 18, a tube pump 121 including a flexible tube 125 crossing the casing 123 along the casing 123 in an α-shape or more has been proposed (for example, Patent Document 1). reference.). That is, in the tube pump 121 in Patent Document 1, the flexible tube 125 has an overlapping portion 133, and the roller 127 always pushes the flexible tube 125 even if there is only one roller 127. It was possible to crush. As a result, the upstream side of the tube pump 121 is not intermittently opened to the downstream side, and the negative pressure can be continuously accumulated on the upstream side.
JP 2001-301195 A

However, since the tube pump 121 in Patent Document 1 has the overlapping portion 133, there is a problem that the space in the direction along the rotation axis increases.
The present invention has been made in view of the above problems, and an object thereof is to provide a tube pump and a liquid ejecting apparatus capable of continuously accumulating negative pressure without increasing space.

The present invention relates to a flexible tube, a casing that accommodates a flow passage intermediate portion of the flexible tube, a rotation shaft in the casing, and a rotation shaft that rotates about the rotation shaft. Pressing means for sequentially crushing the inner wall of the casing by the first abutting member to generate a pressure difference between the upstream side portion and the downstream side portion of the flexible tube with respect to the middle portion of the flow path; In the tube pump comprising: the intermediate portion of the flow path is accommodated so as to draw an arc shape in the casing and not to have an overlapping portion in the direction along the rotation axis. A first position where the flow path intermediate portion is located between the first contact member and the inner wall of the casing by rotating in the forward rotation direction about the rotation axis; and Between the abutting member and the inner wall of the casing so as to be alternately located at a second position where the middle portion of the flow path is not located, and the pressing means is located at the first position. When the flow path of the flexible tube is in an unblocked state and the pressing means is located at the second position, the flow path is in the middle of the flow path of the flexible tube. Choke means for closing the path, the pressing means,
A rotating member that rotates about the rotating shaft and the first abutting member are supported, and a distance from the rotating shaft of the first abutting member is supported with respect to the rotating member so that the distance can be changed. The support member is interposed between the rotation member and the support member, and the support member is attached by an elastic force so that the first contact member supported by the support member is separated from the rotation shaft. And the choke means is a second abutting member supported by the support member so as to face the casing with the middle portion of the flow path in between. The second abutting member is configured such that the abutting portion that abuts against the middle portion of the flow path is closer to the rotating shaft than the portion that the first abutting member abuts against the middle portion of the flow path. It is supported by the support member so that the distance is close. To have.

  According to the present invention, when the pressing means is rotated in the normal rotation direction about the rotation axis, the pressing means is alternately positioned at the first position and the second position. When the pressing means is located at the first position, the first abutting member of the pressing means sequentially crushes the midway portion of the flexible tube in the closed state. Further, when the pressing means is located at the second position, the first abutting member is in a state in which it does not crush the middle portion of the flow path of the flexible tube. When the pressing means is located at the second position, the flow path of the flexible tube is maintained in the closed state by the choke means.

  Therefore, when the pressing means is rotated in the normal rotation direction around the rotation axis, the flexible tube is always maintained in a state where the flow path is closed by the first contact member or the choke means. As a result, the flexible tube is sequentially crushed by the first contact member, so that the pressure difference generated between the upstream portion and the downstream portion of the flexible tube is continuously accumulated. Will be able to.

  At this time, the middle portion of the flow path is accommodated so as not to overlap the casing, so that the space in the direction along the rotation axis of the tube pump can be reduced.

In addition , when the pressing means is located at the second position, the first abutting member does not crush the middle part of the flow path of the flexible tube, but at this time, the flow path of the flexible tube by the choke means. The middle part was blocked.

  Therefore, the position of the flexible tube that is crushed by the first contact member when the pressing means is located at the first position, and the choke means when the pressing means is located at the second position. Both of the positions of the flexible tubes blocked by are the middle portions of the flow path. As a result, in the flexible tube, the crushing position by the first abutting member and the position closed by the choke means become closer, and the pressure difference between the upstream portion and the downstream portion is more varied. It can be accumulated in a state where there is little.

Further , the first support member for generating a pressure difference between the upstream portion and the downstream portion of the flexible tube and the second contact member constituting the choke means are the same support member. To be supported by. The support member is biased by the elastic means so that the first and second contact members are separated from the rotation shaft. In addition, the second contact member is supported by the support member such that the contact portion with respect to the middle portion of the flow path is closer to the rotation axis than the first contact member.

  Therefore, when the first contact member is located at the first position by rotating the rotation member that supports the support member about the rotation axis, the first contact member is a flexible tube. Crush the middle part of the channel. At this time, the support member receives a reaction force from the flexible tube via the first contact member, and approaches the rotating shaft against the elastic force of the elastic means. As a result, the second contact member closer to the rotation shaft than the first contact member is maintained in a state in which the flexible tube is not crushed.

  On the other hand, when the first contact member is located at the second position by rotating the rotating member, the first contact member does not crush the middle portion of the flow path of the flexible tube. The support member is separated from the rotation shaft according to the elastic force of the elastic means. As a result, the second abutting member closer to the rotation axis than the first abutting member can squeeze the middle portion of the flow path of the flexible tube and keep the flow path closed.

  That is, the second abutting member can function as choke means by rotating the rotating member to generate a pressure difference in the flexible tube. As a result, it is not necessary to provide a new driving device such as an actuator for driving the choke means, and the device can be simplified.

  In this tube pump, the support member includes a groove formed so that a distance from the rotation shaft decreases in the forward rotation direction, and the first contact member and the second contact member are provided. The contact member is supported so as to be movable along the groove with respect to the support member.

According to this, the support member is provided with a groove formed so that the distance from the rotation axis becomes smaller in the forward rotation direction. And the 1st contact member and the 2nd contact member are:
The support member is supported so as to be movable along the groove.

  Therefore, by rotating the rotating member around the rotation axis, the first contact member and the second contact member move along the groove due to friction generated between the flexible tube. And it comes to be located in the terminal part of the rotation direction of a groove. As a result, when the rotating member is rotated in the forward rotation direction, both the first abutting member and the second abutting member are located at a position where the distance from the rotating shaft is the largest, and are allowed. The flexible tube can be located at a position where it can be crushed. Further, when the rotating member is rotated in the direction opposite to the normal rotation direction, both the first contact member and the second contact member are located at the position where the distance from the rotation axis is the smallest. Thus, the flexible tube can be positioned so as not to be crushed. As a result, by changing the rotation direction of the rotating member, a pressure difference can be generated or not generated between the upstream portion and the downstream portion of the flexible tube. Therefore, the drive control of the tube pump can be facilitated.

In this tube pump, wherein the first contact member and the second abutment member, an engagement shaft that engages in the groove, is formed by a cylindrical portion whose central axis coincides with Dokakarigojiku, The cylindrical portion of the first contact member is formed to have an outer diameter larger than that of the cylindrical portion of the second contact member.

According to this, the first contact member and a second contact member, respectively, so as to be formed by the engagement shaft and a cylindrical portion engaging in a groove of the support member, a first abutment The cylindrical portion of the member is formed to have an outer diameter larger than that of the cylindrical portion of the second contact member.

Therefore, with a simple configuration, the second abutting member can be positioned closer to the rotation axis than the first abutting member.
In this tube pump, the second abutting member is supported by the support member so as to be adjacent to the rear side of the first abutting member in the direction along the forward rotation direction.

  According to this, the second contact member is supported by the support member so as to be adjacent to the rear of the first contact member in the direction along the forward rotation direction. Therefore, for example, when the second contact member is supported by the support member in the forward direction at a position along the forward rotation direction relative to the first contact member, the first contact member is When located at position 2, the pressure difference accumulated in the flexible tube due to the delay of the second abutment member relative to the first abutment member may be partially impaired.

  However, according to the present invention, when the first contact member is located at the second position, the flexible tube is closed by the second contact member immediately after the first contact member, The pressure difference accumulated in the flexible tube by the first contact member can be maintained in an almost intact state.

The present invention relates to a flexible tube, a casing that accommodates a flow passage intermediate portion of the flexible tube, a rotation shaft in the casing, and a rotation shaft that rotates about the rotation shaft. Pressing means for sequentially crushing the inner wall of the casing by the first abutting member to generate a pressure difference between the upstream side portion and the downstream side portion of the flexible tube with respect to the middle portion of the flow path; In the tube pump comprising: the intermediate portion of the flow path is accommodated so as to draw an arc shape in the casing and not to have an overlapping portion in the direction along the rotation axis. A first position where the flow path intermediate portion is located between the first contact member and the inner wall of the casing by rotating in the forward rotation direction about the rotation axis; and Between the abutting member and the inner wall of the casing so as to be alternately located at a second position where the middle portion of the flow path is not located, and the pressing means is located at the first position. When the flow path of the flexible tube is in an unblocked state and the pressing means is located at the second position, the flow path is in the middle of the flow path of the flexible tube. Choke means for closing the path is provided, and the choke means is opposed to the first contact member with the flexible tube interposed when the pressing means is located at the second position. And a biasing means for biasing the third contact member toward the flexible tube.

According to the present invention, when the pressing means is rotated in the normal rotation direction about the rotation axis, the pressing means is alternately positioned at the first position and the second position. When the pressing means is located at the first position, the first abutting member of the pressing means sequentially crushes the midway portion of the flexible tube in the closed state. Further, when the pressing means is located at the second position, the first abutting member is in a state in which it does not crush the middle portion of the flow path of the flexible tube. When the pressing means is located at the second position, the flow path of the flexible tube is maintained in the closed state by the choke means.
Therefore, when the pressing means is rotated in the normal rotation direction around the rotation axis, the flexible tube is always maintained in a state where the flow path is closed by the first contact member or the choke means. As a result, the flexible tube is sequentially crushed by the first contact member, so that the pressure difference generated between the upstream portion and the downstream portion of the flexible tube is continuously accumulated. Will be able to.
At this time, the middle portion of the flow path is accommodated so as not to overlap the casing, so that the space in the direction along the rotation axis of the tube pump can be reduced.
In addition, when the pressing means is located at the second position, the first abutting member does not crush the middle part of the flow path of the flexible tube, but at this time, the flow path of the flexible tube by the choke means. The middle part was blocked.
Therefore, the position of the flexible tube that is crushed by the first contact member when the pressing means is located at the first position, and the choke means when the pressing means is located at the second position. Both of the positions of the flexible tubes blocked by are the middle portions of the flow path. As a result, in the flexible tube, the crushing position by the first abutting member and the position closed by the choke means become closer, and the pressure difference between the upstream portion and the downstream portion is more varied. It can be accumulated in a state where there is little.
Further, the pressing means are positioned in the second position, the third contact member so as to face each other across the flexible tube against the first contact member. The third abutting member is urged toward the flexible tube by the urging means, and when the pressing means is located at the second position, the third abutting member and the third abutting member are The flexible tube is sandwiched and crushed by one abutting member.

  Therefore, when the pressing means is located at the second position, the flexible tube can be more reliably crushed, and the pressure difference generated between the upstream portion and the downstream portion of the flexible tube can be reduced. Can be accumulated more reliably.

  In this tube pump, when the pressing means is converted into a linear motion and the pressing means is located at the first position based on the rotational movement of the pressing means, the third contact member Is provided with a cam mechanism for pressing in a direction against the urging force of the urging means.

  According to this, by rotating the pressing means, the cam mechanism converts the rotational movement of the pressing means into a linear motion, and when the pressing means is located at the first position, the third contact member is It was made to press in the direction against the urging force by the urging means. Therefore, when the pressing means is located at the first position, when the flexible tube is crushed, the third abutting member is moved in the direction against the urging force by the cam mechanism, and the third abutting member is moved. It is possible to prevent the flexible tube from being crushed by the contact member. Further, when the pressing means is located at the second position, the third abutting member can crush the flexible tube according to the biasing force.

  As a result, the third abutting member can function as the choke means by rotating the pressing means to cause a pressure difference in the flexible tube. As a result, it is not necessary to provide a new driving device such as an actuator for driving the choke means, and the device can be simplified.

The present invention provides a liquid ejecting apparatus that includes a liquid ejecting head that ejects liquid from a nozzle to a target, and a cap that can cover the nozzle of the liquid ejecting head, and one end communicates with the cap. A flexible tube, a casing that accommodates a portion of the flexible tube in the flow path, and a rotating shaft in the casing that rotates around the rotating shaft, thereby causing the flow passage intermediate portion to be a first portion. A tube having pressing means that sequentially crushes toward the inner wall of the casing by an abutting member and generates a pressure difference between the upstream portion and the downstream portion of the flexible tube with respect to the middle portion of the flow path. A pump is provided, and the middle portion of the flow path does not have an overlapping portion so as to draw an arc shape in the casing and in a direction along the rotation axis. The pressing means is rotated in the normal rotation direction around the rotation axis, whereby the first halfway portion of the flow path is located between the first contact member and the inner wall of the casing. And a second position where the middle portion of the flow path is not located between the first contact member and the inner wall of the casing. when located at the first position, while the flow path of the flexible tube and the unobstructed, said pressing means, when positioned in the second position, the said flexible tube Choke means for closing the flow path in the middle of the flow path, and the pressing means supports the rotating member that rotates about the rotation shaft and the first contact member, and the first contact member The distance of the contact member from the rotation axis can be changed. The support member supported with respect to the rotating member, and the first contact member interposed between the rotating member and the supporting member and supported by the supporting member are separated from the rotating shaft. Elastic means for urging the support member by elastic force, and the choke means is supported by the support member so as to confront the casing with the middle portion of the flow path interposed therebetween. The second contact member is a contact portion that contacts the middle portion of the flow path, and the first contact member contacts the middle portion of the flow path. It is supported by the support member so that the distance from the rotation shaft is closer than the portion.

  According to the present invention, when the pressing means of the tube pump is rotated in the normal rotation direction about the rotation axis, the tube pump is alternately positioned at the first position and the second position. When the pressing means is located at the first position, the first abutting member of the pressing means sequentially crushes the midway portion of the flexible tube in the closed state. Further, when the pressing means is located at the second position, the first abutting member is in a state in which it does not crush the middle portion of the flow path of the flexible tube. When the pressing means is located at the second position, the flow path of the flexible tube is maintained in the closed state by the choke means.

Therefore, when the pressing means of the tube pump is rotated in the normal rotation direction around the rotation axis, the flexible tube is always maintained in a state where the flow path is closed by the first contact member or the choke means. The As a result, the flexible tube is sequentially crushed by the first contact member, so that the pressure difference generated between the upstream portion and the downstream portion of the flexible tube is continuously accumulated. Will be able to. Therefore, the negative pressure is continuously accumulated in the cap by sucking the liquid from the liquid ejecting head by rotating the tube pump pressing means in the forward rotation direction with the liquid ejecting head covered by the cap. Can do. As a result, the liquid jet head can be more reliably cleaned.

Further, at this time, in the tube pump, the midway portion of the flow path is accommodated so as not to have an overlapping portion, so that the space in the direction along the rotation axis of the tube pump can be reduced. The overall size can be reduced.
In addition, when the pressing means is located at the second position, the first abutting member does not crush the middle portion of the flow path of the flexible tube, but at this time, the flow of the flexible tube is prevented by the choke means. The middle part of the road was blocked.
Therefore, the position of the flexible tube that is crushed by the first contact member when the pressing means is located at the first position, and the choke means when the pressing means is located at the second position. Both of the positions of the flexible tubes blocked by are the middle portions of the flow path. As a result, in the flexible tube, the crushing position by the first abutting member and the position closed by the choke means become closer, and the pressure difference between the upstream portion and the downstream portion is more varied. It can be accumulated in a state where there is little.
Further, the first support member for generating a pressure difference between the upstream portion and the downstream portion of the flexible tube and the second contact member constituting the choke means are the same support member. To be supported by. The support member is biased by the elastic means so that the first and second contact members are separated from the rotation shaft. In addition, the second contact member is supported by the support member such that the contact portion with respect to the middle portion of the flow path is closer to the rotation axis than the first contact member.
Therefore, when the first contact member is located at the first position by rotating the rotation member that supports the support member about the rotation axis, the first contact member is a flexible tube. Crush the middle part of the channel. At this time, the support member receives a reaction force from the flexible tube via the first contact member, and approaches the rotating shaft against the elastic force of the elastic means. As a result, the second contact member closer to the rotation shaft than the first contact member is maintained in a state in which the flexible tube is not crushed.
On the other hand, when the first contact member is located at the second position by rotating the rotating member, the first contact member does not crush the middle portion of the flow path of the flexible tube. The support member is separated from the rotation shaft according to the elastic force of the elastic means. As a result, the second abutting member closer to the rotation axis than the first abutting member can squeeze the middle portion of the flow path of the flexible tube and keep the flow path closed.
That is, the second abutting member can function as choke means by rotating the rotating member to generate a pressure difference in the flexible tube. As a result, it is not necessary to provide a new driving device such as an actuator for driving the choke means, and the device can be simplified.
The present invention relates to a liquid ejecting apparatus including a liquid ejecting head that ejects liquid from a nozzle to a target, and a cap that can cover the nozzle of the liquid ejecting head.
A flexible tube whose one end communicates with the cap, a casing that accommodates a middle portion of the flow path of the flexible tube, a rotating shaft in the casing, and rotation about the rotating shaft. The intermediate portion of the flow path is sequentially crushed toward the inner wall of the casing by the first abutting member, and a pressure difference is generated between the upstream portion and the downstream portion of the flexible tube with respect to the intermediate portion of the flow path. A tube pump having a pressing means for allowing the intermediate portion of the flow path to be accommodated in the casing so as to draw an arc shape and not to overlap in a direction along the rotation axis. The pressing means rotates in the normal rotation direction around the rotation axis, so that the middle portion of the flow path is located between the first contact member and the inner wall of the casing. And a second position where the middle portion of the flow path is not located between the first contact member and the inner wall of the casing. When positioned at the first position, the flow path of the flexible tube is unoccluded, and when the pressing means is positioned at the second position, Choke means for closing the flow path in the middle of the flow path is provided, and the choke means is configured to be movable with respect to the first contact member when the pressing means is located at the second position. A third abutting member that faces the flexible tube and an urging means that urges the third abutting member toward the flexible tube side.
According to the present invention, when the pressing means of the tube pump is rotated in the normal rotation direction about the rotation axis, the tube pump is alternately positioned at the first position and the second position. When the pressing means is located at the first position, the first abutting member of the pressing means sequentially crushes the midway portion of the flexible tube in the closed state. Further, when the pressing means is located at the second position, the first abutting member is in a state in which it does not crush the middle portion of the flow path of the flexible tube. When the pressing means is located at the second position, the flow path of the flexible tube is maintained in the closed state by the choke means.
Therefore, when the pressing means of the tube pump is rotated in the normal rotation direction around the rotation axis, the flexible tube is always maintained in a state where the flow path is closed by the first contact member or the choke means. The As a result, the flexible tube is sequentially crushed by the first contact member, so that the pressure difference generated between the upstream portion and the downstream portion of the flexible tube is continuously accumulated. Will be able to. Therefore, the negative pressure is continuously accumulated in the cap by sucking the liquid from the liquid ejecting head by rotating the tube pump pressing means in the forward rotation direction with the liquid ejecting head covered by the cap. Can do. As a result, the liquid jet head can be more reliably cleaned.
Further, at this time, in the tube pump, the midway portion of the flow path is accommodated so as not to have an overlapping portion, so that the space in the direction along the rotation axis of the tube pump can be reduced. The overall size can be reduced.
In addition, when the pressing means is located at the second position, the first abutting member does not crush the middle portion of the flow path of the flexible tube, but at this time, the flow of the flexible tube is prevented by the choke means. The middle part of the road was blocked.
Therefore, the position of the flexible tube that is crushed by the first contact member when the pressing means is located at the first position, and the choke means when the pressing means is located at the second position. Both of the positions of the flexible tubes blocked by are the middle portions of the flow path. As a result, in the flexible tube, the crushing position by the first abutting member and the position closed by the choke means become closer, and the pressure difference between the upstream portion and the downstream portion is more varied. It can be accumulated in a state where there is little.
Furthermore, when the pressing means is located at the second position, the third contact member faces the first contact member with the flexible tube interposed therebetween. The third abutting member is urged toward the flexible tube by the urging means, and when the pressing means is located at the second position, the third abutting member and the third abutting member are The flexible tube is sandwiched and crushed by one abutting member.
Therefore, when the pressing means is located at the second position, the flexible tube can be more reliably crushed, and the pressure difference generated between the upstream portion and the downstream portion of the flexible tube can be reduced. Can be accumulated more reliably.

Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS.
As shown in FIG. 1, in an ink jet recording apparatus 11 as a liquid ejecting apparatus of the present embodiment, a platen 13 is installed on a frame 12 and paper P is fed onto the platen 13 by a paper feed mechanism (not shown). Sent. A carriage 15 is supported on the frame 12 via a guide member 16 so as to be movable in the longitudinal direction of the platen 13, and is reciprocated by a carriage motor 17 via a timing belt 18.

  A recording head 20 as a liquid ejecting head is mounted on the carriage 15 below. The recording head 20 includes a nozzle discharge port (not shown) on its lower surface, and ejects ink droplets from the nozzle discharge port by driving a piezoelectric element (not shown).

  An ink cartridge 21 is detachably mounted on the carriage 15, and ink is supplied from the ink cartridge 21 to the recording head 20. Accordingly, while the carriage 15 is moved along the platen 13, the piezoelectric element is driven based on the print data, whereby ink is ejected from the recording head 20 onto the paper P to perform printing.

  A head cleaning mechanism 25 is provided in a non-printable area (home position) on one side of the frame 12. As shown in FIGS. 1 and 2, the head cleaning mechanism 25 includes a cap holder 26 and a tube pump 28. The cap holder 26 is attached to the frame 12 so as to be movable up and down by a known lifting means (not shown).

  On the cap holder 26, a square frame-shaped cap 29 is provided. The cap 29 is configured such that the upper end edge of the cap 29 abuts on the recording head 20 to seal the nozzle discharge port of the recording head 20. As shown in FIG. 2, the cap 29 has a sheet-like sponge 31 fixed to the bottom thereof. The sponge 31 is opposed to the nozzle ejection port of the recording head 20 with a predetermined interval in a state where the cap 29 is in contact with the recording head 20 and receives ink ejected from the nozzle of the recording head 20. ing. Further, the cap 29 is formed with a discharge port 32 so as to penetrate the bottom surface.

  The tube pump 28 decompresses the inside of the cap 29 in a state where the nozzle discharge port of the recording head 20 is sealed, sucks ink from the recording head 20, and supplies the ink to a waste ink tank 33 provided in the frame 12. It is for discharging.

Specifically, as shown in FIG. 3, the tube pump 28 includes a casing 35, a discharge tube 36, and a pressing device 37 as pressing means. The casing 35 is formed of a resin into a bottomed cylindrical shape, and a support hole 39 is formed through the center of the bottom surface 38 thereof. Further, a cutout portion 41 is formed in a part of the side surface of the casing 35 so as to cut out from the upper side to the lower side of the bottom surface 38. The casing 35 is provided with a groove 42 projecting from the notch 41 so as to extend outward in the radial direction of the casing 35. Further, two fitting convex portions 43 and 44 extending in the vertical direction are provided inside the groove portion 42, and the fitting convex portions 43 and 44 face each other.

  The discharge tube 36 is a tube formed of a flexible member such as silicon rubber. In the present embodiment, as shown in FIG. 4, the discharge tube 36 includes two flexible tubes 46 and 47. The flexible tubes 46 and 47 are connected and integrated by an attachment portion 48. The flexible tubes 46 and 47 are formed with flow paths 46a and 47a, respectively.

  As shown in FIG. 3, the discharge tube 36 includes the upstream end 50 and the downstream end 51 of the middle portion 49 of the flow path in a state where the flexible tubes 46 and 47 are arranged in the vertical direction. However, they are bundled so that the flow directions are opposite to each other. As a result, the flow path middle portion 49 draws a substantially arc shape. The upstream end 50 and the downstream end 51 are bundled by a resin fastening part 53 formed in a substantially rectangular parallelepiped shape to form a bundle part 52. Specifically, the fastening part 53 The upstream end portion 50 and the downstream end portion 51 are simultaneously inserted into the insertion hole 53a provided in the inner hole 53a. The fastening portion 53 is formed with fitting grooves 54 and 55 so as to extend in the vertical direction on two opposing side surfaces.

  As shown in FIG. 2, the upstream portion 36 a of the discharge tube 36 is connected to the discharge port 32 of the cap 29. Further, the downstream portion 36 b is connected to the waste ink tank 33.

  As shown in FIG. 3, the discharge tube 36 slides the fastening portion 53 downward from above with respect to the groove portion 42 of the casing 35, so that the fitting grooves 54, 55 of the fastening portion 53 and the groove portion 42. It is attached to the casing 35 by engaging the fitting convex portions 43 and 44 respectively. As a result, the midway portion 49 of the discharge tube 36 is accommodated along the cylindrical inner wall 35a of the casing 35, and draws an Ω shape when viewed in the planar direction.

  As shown in FIG. 5, the pressing device 37 includes a rotating member 56, a torsion spring 57 as an elastic means, a support member 58, a first contact member 59a, a second contact member 59b as a choke means, and a fastener. 60.

  The rotating member 56 includes a rotating shaft 61 and a disk portion 62 that are integrally formed of resin. The rotating shaft 61 is provided in order from the upper side such that a small diameter portion 63 and a large diameter portion 64 having a larger diameter than the small diameter portion 63 are positioned on the axis A shown in FIG.

  The disk portion 62 is provided in the middle of the large diameter portion 64 so that its center is located on the axis A and is orthogonal to the rotation shaft 61. And the 1st fitting surface 65 (refer FIG. 8, FIG. 10) which has a shape which is notched flatly in the direction of the axial center A in the part above the said disk part 62 of the large diameter part 64 is provided. Is formed. In addition, a second fitting surface 67 having a shape that is notched from the lower side to the middle in the direction of the axis A is formed in a portion of the large-diameter portion 64 below the disk portion 62. Yes.

The disc part 62 has an outer diameter smaller than the inner diameter of the casing 35. An upper circular through hole 68 and an upper rectangular through hole 69 are formed through the disk portion 62 along the axis A direction. The upper circular through hole 68 and the upper rectangular through hole 69 have a circular and rectangular cross-sectional shape, respectively.

  Moreover, as shown in FIG. 6, the disk part 62 is provided with the protrusion 70 in the lower surface 62a. The protrusion 70 includes a first protrusion 70a, a second protrusion 70b, and a third protrusion 70c that are arranged in order from the top. The first protrusion 70a has a fan shape with the axis A as the center and a diameter smaller than that of the disk part 62, and the second protrusion 70b has a fan shape with a diameter smaller than that of the first protrusion 70a. . And the 3rd protrusion 70c is provided so that the cross-sectional shape of a planar direction may become a substantially triangular shape.

  The first protrusion 70a, the second protrusion 70b, and the third protrusion 70c have a left side surface that is flush with each other in FIG. Yes. In addition, in FIG. 6, the first protrusion 70a and the second protrusion 70b have the same right side surface in FIG. 6, but the second protrusion 70b and the third protrusion 70c Are not flush with each other, but a stepped portion 72 is formed.

  As shown in FIG. 5, the torsion spring 57 is a spring that generates a force returning to the torsion, and includes a coil portion 73 and two arms 73 a and 73 b formed at the end of the coil portion 73. ing. The inner diameter of the coil portion 73 is larger than the outer diameter of the large diameter portion 64 of the rotating shaft 61 in the rotating member 56. The arms 73a and 73b are provided so as to extend in a direction perpendicular to the axis A when the central axis of the coil portion 73 is positioned on the axis A. Moreover, the arm 73a and the arm 73b are expanded at a predetermined angle.

  The support member 58 includes an insertion hole 58a that is parallel to the axis A at the center, and includes an upper plate 75 and a lower plate 76 that are substantially donut shaped. The side plates 75 and 76 are positioned so as to be orthogonal to the axis A, are connected by a connecting portion 77, and are integrally formed of resin.

  The upper plate 75 has an outer diameter smaller than the disk portion 62 of the rotating member 56 and an inner diameter larger than the outer diameter of the torsion spring 57. A part thereof is cut out in a fan shape along the direction of the axis A, and an upper plate side opening 75a is formed. The upper plate 75 has a cylindrical first upper protrusion 78 and a second upper protrusion 79 projecting from the upper surface thereof. The first upper protrusion 78 is formed in a size that can be pivotably fitted into the upper circular through hole 68 formed in the rotating member 56. Further, the second upper convex portion 79 is formed in such a size as to be fitted to the upper rectangular through hole 69 of the rotating member 56 so as to be movable in the longitudinal direction of the upper rectangular through hole 69.

  Further, the upper plate 75 is formed with a through groove 81 as a groove. Specifically, the through-groove 81 is provided substantially halfway along the circumferential direction near the middle of the upper plate 75 in the radial direction, and the distance from the center of the upper plate 75 is from the start end S to the end. It is provided so as to gradually become farther toward the part E as it goes in the direction of the arrow D1 in FIG. In the present embodiment, a predetermined portion from the terminal end E of the through groove 81 is provided so that the distance from the center of the upper plate 75 is equal.

  The lower plate 76 has an outer diameter that is smaller than the outer diameter of the upper plate 75 and an inner diameter that matches the inner diameter of the upper plate 75. The lower plate 76 has a shape such that a part (not shown) of the outer surface thereof coincides with the inner surface 81a of the through groove 81 of the upper plate 75 when viewed in a planar direction. . The lower plate 76 has two cylindrical lower convex portions (not shown) projecting from the lower surface thereof. These lower convex portions are provided at positions where they overlap with the upper convex portions 78 and 79 of the upper plate 75 when viewed in a planar direction, and the size of the lower convex portions also corresponds to the corresponding upper convex portions. It has the same size as the portions 78 and 79.

  The connecting portion 77 has an arc shape in cross section in a direction orthogonal to the axis A. The connecting portion 77 is formed with a connecting portion side opening 77 a that is continuous from the upper plate side opening 75 a of the upper plate 75 and is cut out in a fan shape along the axis A. A locking projection 83 protrudes from the right inner wall surface 82 of the connecting portion side opening 77a shown in FIG. The locking projection 83 is provided such that the longitudinal direction thereof is along the axis A, and the lower end thereof is not in contact with the lower surface 84 of the connecting portion side opening 77a. Yes. As a result, a stepped portion 85 is formed between the locking projection 83 and the lower surface 84 of the connecting portion side opening 77a. The rotating member 56, the torsion spring 57, and the support member 58 constitute biasing means.

  The first abutting member 59 a is provided on the lower surface of the columnar first cylindrical portion 87, the shaft portion 88 as an engagement shaft provided on the upper surface of the first cylindrical portion 87, and the lower surface. It is comprised by the axial part (not shown) as an engaging shaft. The first cylindrical portion 87, the upper shaft portion 88, and the lower shaft portion are arranged such that their central axes are located in the same straight line parallel to the axis A. In the first contact member 59 a, the upper shaft portion 88 is fitted into the through groove 81 of the upper plate 75 from the lower side, and the lower shaft portion is brought into contact with the outer surface of the lower plate 76. This restricts the movement of the support member 58 in the radial direction. Further, the lower surface of the first cylindrical portion 87 is in contact with the upper surface 76a of the lower plate 76 of the support member 58, whereby the first contact member 59a is restricted from moving downward in the direction of the axis A. The

  Similarly to the first contact member 59a, the second contact member 59b also has a columnar second columnar portion 91 and an engagement provided on the upper surface of the second columnar portion 91. A shaft portion 93 as a shaft and a shaft portion 95 (see FIG. 7) as an engagement shaft provided on the lower surface of the second cylindrical portion 91 are configured. The second cylindrical portion 91 and the shaft portions 93 and 95 are arranged such that their central axes are located on the same straight line parallel to the axis A. In the second contact member 59 b, the upper shaft portion 88 is fitted into the through groove 81 of the upper plate 75 from below, and the lower shaft portion 95 is in contact with the outer surface of the lower plate 76. As a result, movement of the support member 58 in the radial direction is restricted. Then, the lower surface of the second cylindrical portion 91 is brought into contact with the upper surface 76a of the lower plate 76 of the support member 58, whereby the second contact member 59b is restricted from moving downward in the direction of the axis A. The

  The outer diameter of the second cylindrical portion 91 of the second contact member 59b is smaller than the outer diameter of the first cylindrical portion 87 of the first contact member 59a. Further, the first and second contact members 59a and 59b are arranged in order from the start end S side along the direction of the arrow D1 in FIG. The two abutting members 59b are supported in order.

  In the above state, the first and second contact members 59a and 59b can rotate around the central axes of the first and second cylindrical portions 87 and 91, respectively, and at the same time, the through groove 81 5 can freely reciprocate along the through-groove 81 between the position near the start end S in the direction of arrow D1 and the position close to the end E in FIG.

The fastener 60 has a center located on the axis A and is formed in a disk shape orthogonal to the axis A, and has an outer diameter smaller than that of the lower plate 76 of the support member 58. It has become. Further, the fastener 60 is formed with a center hole 97 having a shape coincident with the large diameter portion 64 of the rotating member 56 at the center thereof. Therefore, a straight line portion 97 a having a shape that matches the second fitting surface 67 of the large diameter portion 64 is formed in the center hole 97. Further, the fastener 60 includes a lower circular through hole 98 and a lower rectangular through hole 99 at the peripheral edge thereof. The lower circular through hole 98 has the same size and shape as the upper circular through hole 68 of the rotating member 56. The lower rectangular through hole 99 has the same size and shape as the upper rectangular through hole 69 of the rotating member 56.

  The pressing device 37 including the rotating member 56, the torsion spring 57, the support member 58, the first and second contact members 59 a and 59 b, and the fastener 60 as described above is first configured to rotate the rotating shaft of the rotating member 56. The torsion spring 57 is externally fitted to 61 from below. Then, the arm 73 a of the torsion spring 57 is engaged with the stepped portion 72 (see FIGS. 6 and 7) of the rotating member 56.

  Next, the rotating shaft 61 of the rotating member 56 is inserted from above into a through hole 58 a provided at the center of the support member 58. Note that first and second contact members 59a and 59b are attached to the support member 58 in advance. And the protrusion 70 (refer FIG. 6) of the rotation member 56 is located in the upper side board side opening part 75a and the connection part side opening part 77a of the support member 58. As shown in FIG. Further, the arm 73b of the torsion spring 57 is engaged with the stepped portion 85 of the support member 58 (see FIG. 7). Thereafter, the first upper convex portion 78 and the second upper convex portion 79 of the support member 58 are fitted into the upper circular through hole 68 and the upper rectangular through hole 69 of the rotating member 56, respectively.

  Subsequently, the rotary shaft 61 inserted through the support member 58 is inserted through the center hole 97 of the fastener 60. At this time, since the second fitting surface 67 of the rotating shaft 61 and the straight portion 97a of the center hole 97 are engaged, the fastener 60 is attached to the rotating member 56 so as not to rotate. Further, the lower convex portion of the support member 58 is fitted into the lower circular through hole 98 and the lower rectangular through hole 99 of the fastener 60, respectively.

  The pressing device 37 is assembled as described above. As shown in FIG. 7, the pressing device 37 is maintained so that the angle formed by the arms 73a and 73b of the torsion spring 57 is slightly reduced. A force is generated on the spring 57 to return to the torsion. As a result, in a state where no external force is applied to the pressing device 37, the rotating member 56 and the supporting member 58 are engaged with the protrusion 70 of the rotating member 56 and the supporting member 58 by the torsion spring 57. The projection 83 is biased so as to be separated.

  Accordingly, as shown in FIG. 8, the support member 58 rotates in the direction of the arrow shown in FIG. 8 with the first upper convex portion 78 and the lower convex portion fitted in the upper circular through hole 68 as the center. The power to do is added. As a result, in a state where no force is applied from the outside, the second upper convex portion 79 and the lower convex portion of the support member 58 are the upper rectangular through hole 69 and the lower rectangular through hole 99 (FIG. 5), respectively. (Refer to FIG. 8).

  Further, as shown in FIG. 9, when a force is applied to the pressing device 37 such that the angle formed by the arms 73a and 73b is reduced against the force of returning to the torsion of the torsion spring 57, the supporting device is supported. As shown in FIG. 10, the member 58 rotates around the first upper convex portion 78 and the lower convex portion in the arrow direction shown in FIG. 10. And the 2nd upper side convex part 79 and the lower side convex part of the support member 58 are located in the left corner shown in FIG. 10 of the upper side rectangular through-hole 69 and the lower side rectangular through-hole 99 (refer FIG. 5), respectively. Become. As shown in FIG. 9, the distance between the protrusion 70 of the rotating member 56 and the locking protrusion 83 of the support member 58 is reduced.

  Therefore, when the first and second contact members 59a and 59b are located at positions close to the terminal end E (see FIG. 5) of the through groove 81, the first and second contact members 59a and 59b When no force is applied to 59b from the outside, the first and second contact members 59a and 59b are located at a separated position relatively away from the axis A, as shown in FIG. Come to be located.

As shown in FIG. 9, when any force is applied to the support member 58 from the outside, the first and second contact members 59 a and 59 b are positioned closer to the shaft center A than the separated position. It will be located at a close approach position. Then, when the force applied to the support member 58 is changed, the first and second contact members 59a and 59b are positioned at positions near the terminal end E of the through groove 81 according to the magnitude of the force. It comes to be located at any position between the separation position and the approach position.

  At this time, as described above, the first contact member 59a has an outer diameter of the first cylindrical portion 87 (see FIG. 5), and the second cylindrical portion 91 (see FIG. 5) of the second contact member 59b. 5)). Therefore, as shown in FIGS. 7 and 9, the first contact member 59a is always more than the second contact member 59b, regardless of whether the first contact member 59a is located at the separation position or the approach position. It is located in a state of protruding toward a space further away from the axis A.

  As shown in FIG. 11, the pressing device 37 configured as described above is configured such that the rotating shaft 61 of the pressing device 37 has a support hole 39 of the casing 35 with respect to the casing 35 to which the discharge tube 36 is attached. (See FIG. 3). At this time, the first and second abutting members 59a and 59b of the pressing device 37 abut against the midway portion 49 of the discharge tube 36 from the inside. And the tube pump 28 is completed by the above. At this time, the through-groove 81 formed in the support member 58 of the pressing device 37 has a distance from the rotation shaft 61 in the direction of arrow D2 shown in FIG. According to, it is provided to gradually get closer.

  And in this embodiment, when the 1st and 2nd contact members 59a and 59b are located in the position near end part E of penetration groove 81, it is as follows, It is assumed that the shape and the like of the through groove 81 and the first and second contact members 59a and 59b are determined.

  That is, as shown in FIG. 11, when the first abutting member 59 a is opposed to a portion other than the bundle portion 52 of the flow path middle portion 49, the reaction force from the middle portion 49 of the flow path It is assumed that the shape of the through groove 81 and the like is determined so that the support member 58 is located at a position close to the approach position (see FIG. 9). In the present embodiment, the position of the first contact member 59a at this time corresponds to the first position.

  At this time, the middle part 49 of the flow path is crushed by the first contact member 59a, and the flow path is closed. At this time, the second contact member 59b is in contact with the midway portion 49 of the flow path so as not to be crushed.

  On the other hand, as shown in FIG. 12, when the first abutting member 59a is opposed to the bundle portion 52 of the flow path intermediate portion 49, the reaction force from the flow passage intermediate portion 49 is reduced. It is assumed that the shape of the through groove 81 and the like is determined so that the support member 58 is located at a position close to the separation position (see FIG. 7) by the elastic force of the torsion spring 57. In the present embodiment, the position of the first contact member 59a at this time corresponds to the second position.

  At this time, the first contact member 59a is in a state where it cannot press the bundle portion 52 of the midway portion 49 of the flow path with sufficient force. Therefore, in the present embodiment, when the first contact member 59a is opposed to the bundle portion 52, the flow path of the middle portion 49 of the flow path is not blocked by the first contact member 59a.

On the other hand, when the first contact member 59a is opposed to the bundle portion 52, the second contact member 59b is compared with the first contact member 59a when the first contact member 59a is located at the first position. Thus, it is located at a position separated from the rotation shaft 61. Therefore, in such a case, the middle portion 49 of the flow path is crushed by the second contact member 59b. Therefore, in the present embodiment, when the first contact member 59a is opposed to the bundle portion 52, the flow path in the middle portion 49 of the flow path is closed only by the second contact member 59b. It is like that.

  Furthermore, in the present embodiment, when the first and second contact members 59a, 59b are located at a position near the starting end S of the through groove 81, the following relationship is established. It is assumed that the shape and the like of the through groove 81 and the first and second contact members 59a and 59b are determined.

  That is, as shown in FIG. 13, even if the first contact member 59a is opposed to any part of the flow path middle part 49, the first contact member 59a causes the flow path middle part 49 to It is assumed that the shape and the like of the through groove 81 and the first contact member 59a are determined so that the flow path is not blocked. At this time, it is assumed that the shape of the second contact member 59b is determined so that the flow path in the flow path middle portion 49 cannot be closed. Therefore, in the present embodiment, when the first and second contact members 59a and 59b are positioned closer to the start end S, the flow path of the flow path middle portion 49 is always kept open. .

Next, the operation of the ink jet recording apparatus 11 configured as described above will be described.
First, the case where the recording head 20 is cleaned in the ink jet recording apparatus 11 will be described. In such a case, the carriage 15 moves to the home position, and the recording head 20 is covered with the cap 29. As shown in FIG. 11, in the tube pump 28, the rotating member 56 of the pressing device 37 is rotated in the direction of the arrow D2 (forward rotation direction) shown in FIG.

  Then, each of the first and second contact members 59a and 59b supported by the support member 58 has a normal rotation direction due to the frictional force generated between the discharge tube 36 and the middle portion 49 of the flow path. Force in the opposite direction is applied. As a result, the first and second contact members 59a and 59b move along the through groove 81 of the support member 58 and come to a position near the terminal end E.

  In the tube pump 28, the rotation of the rotating member 56 in the forward rotation direction is continued in a state where the first and second contact members 59a and 59b are positioned near the terminal end E of the through groove 81. The As a result, when the first contact member 59a is not facing the bundle portion 52 of the flow path intermediate portion 49, the flow passage intermediate portion 49 is sequentially crushed by the first contact member 59a. . As a result, the middle portion 49 of the flow channel undergoes a volume change inside with the flow channel closed. And thereby, the pressure of the upstream part 36a of the discharge tube 36 becomes lower than the pressure of the downstream part 36b.

  As shown in FIG. 12, when the first abutting member 59 a faces the bundle portion 52 of the flow path middle portion 49, the first abutting member 59 a Will not crush. However, at this time, since the support member 58 is moved so as to be located at a position close to the separation position, the midway portion 49 of the flow path is crushed in the vicinity of the bundle portion 52 by the second contact member 59b.

That is, the tube pump 28 is rotated forward so that when the first abutting member 59a is not facing the bundle portion 52, the channel middle portion 49 is crushed by the first abutting member 59a, A negative pressure can be formed in the upstream portion 36 a of the discharge tube 36. Further, when the first abutting member 59a faces the bundle portion 52, the second abutting member 59b can keep the closed state in the middle portion 49 of the flow path.

  Therefore, the tube pump 28 always maintains the first abutting member 59a or the second abutting member while the rotating member 56 is rotated in the forward direction, regardless of the position of the first abutting member 59a. Any part of the flow path intermediate portion 49 is crushed by the contact member 59b. And the upstream part 36a of the discharge tube 36 is not opened to the downstream part 36b. As a result, it is possible to prevent the pressure pulsation generated by the rotation of the rotating member 56 continuously in the forward rotation direction, and to effectively suppress the generation of noise and the like based on the pulsation. The pressure can be accumulated continuously and efficiently from the first rotation to the second rotation, from the second rotation to the third rotation. As a result, the pressure inside the cap 29 connected to the upstream portion 36a of the discharge tube 36 can be effectively reduced, and ink and bubbles can be effectively sucked from the nozzle openings of the recording head 20. Can do.

  On the other hand, when the cleaning is completed, as shown in FIG. 13, in the tube pump 28, the rotating member 56 of the pressing device 37 is rotated a predetermined number of times in the direction of the arrow D3 (reverse direction) shown in FIG. Is done. Then, the first and second contact members 59a and 59b supported by the support member 58 are opposite to the reverse direction due to the frictional force generated between the flow passage intermediate portion 49 of the discharge tube 36. A force in the direction is applied. As a result, the first and second contact members 59a and 59b move along the through groove 81 of the support member 58 and are positioned at the start end S. The first and second abutting members 59a and 59b come into light contact with each other at the start end S without crushing the midway portion 49 of the discharge tube 36.

  As a result, the flow path middle portion 49 of the discharge tube 36 is opened, and no pressure difference is generated in the discharge tube 36. Then, during printing of the ink jet recording apparatus 11 or when the ink jet recording apparatus 11 is stopped for a long time, the ink jet recording apparatus 11 is left in this state for a long time, so that the discharge tube 36 is prevented from being deformed or deteriorated in durability.

According to the above embodiment, the following effects can be obtained.
(1) In the above embodiment, when the pressing device 37 is rotated in the direction of arrow D2 (forward rotation direction), the first contact member 59a provided in the pressing device 37 is in the middle of the flow path of the discharge tube 36. The position facing the portion 49 and the position facing the bundle portion 52 are alternately positioned. And when the 1st contact member 59a opposes the flow path middle part 49 of the discharge tube 36, the flow path middle part 49 was sequentially crushed by the 1st contact member 59a. Further, when the first abutting member 59a faces the bundle portion 52, the first abutting member 59a does not crush the channel middle portion 49. And when the 1st contact member 59a is facing the bundle part 52, the flow path middle part 49 was crushed and maintained by the 2nd contact member 59b. .

  Therefore, when the pressing device 37 is rotated in the forward rotation direction, the discharge tube 36 is always maintained in a state where the flow path is closed by the first contact member 59a or the second contact member 59b. As a result, when the discharge tube 36 is sequentially crushed by the first contact member 59a, the pressure difference generated between the upstream portion 36a and the downstream portion 36b of the discharge tube 36 is continuously accumulated. To be able to.

  Accordingly, by driving the tube pump 28 with the recording head 20 covered by the cap 29, negative pressure can be continuously accumulated in the cap 29 and ink can be sucked from the recording head 20. As a result, the recording head 20 can be more reliably cleaned.

  (2) In the embodiment described above, the flow path middle portion 49 is accommodated so as not to overlap with the casing 35 so as to draw an Ω character. Therefore, the space of the tube pump 28 in the direction along the rotation shaft 61 can be reduced. As a result, the overall size of the ink jet recording apparatus 11 can be reduced.

  (3) In the above embodiment, the second abutting member 59b is the middle part of the flow path in the discharge tube 36 when the first abutting member 59a faces the bundle portion 52. 49 is supported with respect to the support member 58 so as to press.

  Therefore, when the first abutting member 59a faces the channel middle portion 49, the position of the discharge tube 36 to be crushed by the first abutting member 59a and the first abutting member 59a are the bundle portion 52. When facing each other, the position of the discharge tube 36 that is crushed by the second abutting member 59b together becomes the middle portion 49 of the flow path. As a result, the crushing position by the first abutting member 59a and the crushing position by the second abutting member 59b in the discharge tube 36 become closer, and the upstream portion 36a and the downstream portion 36b of the discharge tube 36 Can be accumulated in a state with less fluctuation.

  (4) In the above embodiment, the first contact member 59a for generating a pressure difference between the upstream portion 36a and the downstream portion 36b of the discharge tube 36, and the second contact member 59b Are supported by the same support member 58. The support member 58 is biased by the torsion spring 57 so that the first and second contact members 59 a and 59 b are separated from the rotation shaft 61. Further, the second contact member 59b is supported by the support member 58 so that the contact portion with respect to the flow path middle portion 49 is closer to the rotation shaft 61 than the first contact member 59a. I did it.

  Therefore, when the rotating member 56 that supports the supporting member 58 is rotated about the rotating shaft 61, when the first abutting member 59a is opposed to the middle portion 49 of the flow path, the first contact is made. The contact member 59a crushes the midway portion 49 of the flow path. At this time, the support member 58 receives a reaction force from the discharge tube 36 via the first contact member 59a, and approaches the rotating shaft 61 against the elastic force of the torsion spring 57. As a result, the second contact member 59b closer to the rotation shaft 61 than the first contact member 59a is maintained in a state in which the discharge tube 36 is not crushed.

  On the other hand, when the first contact member 59a is opposed to the bundle portion 52 by rotating the rotating member 56, the first contact member 59a does not crush the midway portion 49 of the flow path. 58 is separated from the rotating shaft 61 according to the elastic force of the torsion spring 57. As a result, the second abutting member 59b closer to the rotation shaft 61 than the first abutting member 59a can crush the midway portion 49 of the flow path and maintain the flow path closed.

  That is, only by rotating the rotation member 56, a pressure difference is generated in the discharge tube 36 by the first contact member 59a, and the flow path in the discharge tube 36 is closed by the second contact member 59b. Or not. As a result, it is not necessary to provide a new drive device such as an actuator in order to drive the second contact member 59b, and the device can be simplified.

  (5) In the above embodiment, the through-groove 81 formed in the support member 58 of the pressing device 37 has a distance from the rotation shaft 61 from the end E toward the start S, as shown in FIG. As it went in the direction of D2, it gradually became closer. The first and second contact members 59 a and 59 b are supported so as to be movable along the through groove 81 with respect to the support member 58.

  Therefore, by rotating the rotation member 56 of the pressing device 37 around the rotation shaft 61, the first and second contact members 59a and 59b are caused by friction generated between the flow path middle portion 49 and It moves along the through groove 81 and comes to be located at the terminal end E of the through groove 81. As a result, when the rotating member 56 is rotated in the forward rotation direction, the first and second contact members 59a and 59b are both positioned at the position where the distance from the rotating shaft 61 is the largest, It can be made to be located in the position which can crush halfway part 49. When the rotating member 56 is rotated in the reverse rotation direction, both the first and second contact members 59a and 59b are positioned at the position where the distance from the rotating shaft 61 is the smallest, The discharge tube 36 can be positioned so as not to be crushed. As a result, by changing the rotation direction of the rotating member 56, it is possible to cause or not cause a pressure difference between the upstream portion 36a and the downstream portion 36b of the discharge tube 36. Therefore, the drive control of the tube pump 28 can be facilitated.

  (6) In the above embodiment, the first and second contact members 59a and 59b are respectively connected to the shaft portions 88, 93, and 95 that engage with the through groove 81 of the support member 58, and the first and second members. The cylindrical portions 87 and 91 are formed. The first cylindrical portion 87 is formed to have an outer diameter larger than that of the second cylindrical portion 91.

  Therefore, with a simple configuration, the second abutting member 59b is arranged such that the abutting portion with respect to the flow path middle portion 49 is closer to the rotation shaft 61 than the first abutting member 59a. it can.

  (7) In the above embodiment, the second contact member 59b is supported by the support member 58 so as to be adjacent to the rear of the first contact member 59a in the direction along the forward rotation direction. I did it. Therefore, for example, when the second contact member 59b is supported by the support member 58 in the forward direction in the direction along the forward rotation direction than the first contact member 59a, the second contact member 59b. The pressure difference accumulated in the discharge tube 36 due to the delay of the member 59b with respect to the first contact member 59a may be partially damaged. However, according to the present embodiment, when the first abutting member 59a is located at a position facing the bundle portion 52, the discharge tube 36 is disposed immediately after the first abutting member 59a. It is closed by the contact member 59b. Therefore, the pressure difference accumulated in the discharge tube 36 by the first abutting member 59a can be maintained in a state that is hardly impaired.

In addition, you may change the said embodiment as follows.
In the above embodiment, when the first abutting member 59 a faces the bundle portion 52, the tube pump 28 is blocked at the midway portion 49 of the channel by the second abutting member 59 b. It was made to be. Alternatively, the flow path may be closed at a position other than the flow path middle portion 49 of the discharge tube 36 when the first contact member 59 a faces the bundle portion 52.

  In the above embodiment, the first and second contact members 59 a and 59 b are supported by the through groove 81 of the support member 58. Instead of providing the through groove 81 in the support member 58, the first and second contact members 59a and 59b may be supported so as not to move with respect to the support member 58.

  In the above embodiment, each of the first and second contact members 59a and 59b is formed by the shaft portions 88, 93 and 95 and the first and second cylindrical portions 87 and 91. . This is connected to the first and second contact members 59a. 59b may be changed to other shapes.

  In the above-described embodiment, the first and second contact members 59a and 59b have different outer diameters of the first and second columnar portions 87 and 91, so that the rotary shaft 61 and the flow path intermediate portion 49 are different from each other. The distance to the contact position was made different. Alternatively, the distance from the rotation shaft 61 to the contact position of each of the first and second contact members 59a and 59b may be made different by other methods.

  In the above embodiment, the second contact member 59b is positioned behind the first contact member 59a in the forward rotation direction and is supported by the through groove 81 of the support member 58. . Alternatively, the second contact member 59b may be supported by the through groove 81 of the support member 58 so that the second contact member 59b is positioned forward of the first contact member 59a in the forward rotation direction. .

  In the above embodiment, the second abutting member 59b is embodied as the choke means. As shown in FIG. 14, this may be embodied in a choke device 101 provided in the tube pump 28 as choke means.

  The choke device 101 includes a frame portion 102 formed integrally with the casing 35 outside the casing 35, and a sliding portion 104 as a third abutting member that can slide in the frame portion 102. And a cam portion 106 as a cam mechanism that can rotate integrally with the rotation shaft 61. The sliding portion 104 includes a pressed portion 108 that comes into contact with the cam portion 106, and a tube pressing portion 110 that comes into contact with the midway portion 49 of the discharge tube 36 in the vicinity of the bundle portion 52. The tube pressing portion 110 can be brought into contact with the midway portion 49 of the flow path from the outside of the casing 35 by being inserted into a casing hole 35 b formed in the casing 35.

  And the sliding part 104 is urged | biased by the spring member 112 as an urging | biasing means toward the direction where the tube press part 110 presses the flow path middle part 49. FIG. The cam portion 106 is formed in a substantially disc shape, and includes a cutout portion 114 formed so as to cut out a part thereof.

  Then, in the tube pump 28 formed as described above, when the pressing device 37 is rotated in the direction of arrow D2 (forward rotation direction) shown in FIG. The middle portion 49 of the flow path is sequentially crushed by the member 59a. At this time, when the first abutting member 59a is opposed to the middle portion 49 of the flow path at a position other than the bundle portion 52, the sliding portion 104 is caused by the action of the cam portion 106 and the pressed portion 108. The spring member 112 is moved outwardly of the casing 35 against the urging force of the spring member 112. Therefore, the tube pressing portion 110 can prevent the channel middle portion 49 from being pressed.

  On the other hand, as shown in FIG. 15, when the first abutting member 59 a is in a position facing the bundle portion 52, the sliding portion 104 is moved by the spring member 112 due to the action of the cam portion 106 and the pressed portion 108. According to the urging force, the casing 35 is moved in the inner direction. Therefore, the channel pressing portion 110 and the first contact member 59a can sandwich the channel middle part 49 and close the channel.

  That is, even if the choke device is embodied in such a choke device 101, the pressure difference generated between the upstream portion 36a and the downstream portion 36b of the discharge tube 36 can be continuously accumulated.

In the choke device 101, the sliding portion 104 is driven by the action of the cam portion 106, but the sliding portion 104 may be driven by other driving means.

In the above embodiment, the torsion spring 57 is used as the elastic means, but other elastic means such as rubber, tension springs, leaf springs, etc. may be used.
In the above embodiment, the discharge tube 36 is configured by the two flexible tubes 46 and 47, but may be configured by only one flexible tube. Moreover, you may make it comprise with three or more flexible tubes.

In the above embodiment, the flexible tubes 46 and 47 constituting the discharge tube 36 are connected by the attachment portion 48, but may not be connected.
In the above embodiment, the tube pump 28 has been described as an apparatus used for cleaning the ink jet recording apparatus 11, but may be used for other purposes.

  In the above-described embodiment, the ink jet recording apparatus (printing apparatus including a fax machine, a copier, etc.) 11 that ejects ink has been described as the liquid ejecting apparatus. However, the liquid ejecting apparatus may eject other liquids. Good. For example, a liquid ejecting apparatus for ejecting a liquid such as an electrode material or a color material used for manufacturing a liquid crystal display, an EL display, an FED (surface emitting display), or the like, or a liquid ejecting apparatus for ejecting a bioorganic material used for biochip manufacturing A sample injection device as a precision pipette may be used.

1 is a perspective view of an ink jet recording apparatus according to an embodiment. Similarly, the principal part schematic block diagram of an inkjet recording device. Similarly, the partial exploded perspective view of a tube pump. Similarly, the fragmentary perspective view of a discharge tube. Similarly, an exploded perspective view of the pressing device. Similarly, the perspective view of a rotating member. Similarly, the front view of a pressing device. Similarly, the top view of a pressing device. Similarly, the front view of a pressing device. Similarly, the top view of a pressing device. Similarly, the partially broken top view of a tube pump. Similarly, the figure explaining the effect | action of a tube pump. Similarly, the figure explaining the effect | action of a tube pump. The partially broken top view of the tube pump in another example. The figure explaining the effect | action of the tube pump in another example. The schematic block diagram of the tube pump in the past. The schematic block diagram of the tube pump in the past. The schematic block diagram of the tube pump in the past.

Explanation of symbols

  P: paper as a target, 11: ink jet recording apparatus as a liquid ejecting apparatus, 20 ... recording head as a liquid ejecting head, 28 ... tube pump, 29 ... cap, 35 ... casing, 36a ... upstream portion, 36b ... Downstream portion, 37: pressing device as pressing means, 46, 47 ... flexible tube, 46a, 47a ... flow path, 49 ... middle portion of flow path, 56 ... rotating member, 57 ... torsion spring as elastic means, 58 ... support member, 59a ... first contact member, 59b ... second contact member as choke means, 61 ... rotating shaft, 81 ... through-groove as groove, 87, 91 ... first and second Column part, 88, 93, 95 ... Shaft part as engagement shaft, 104 ... Sliding part as third abutting member, 106 ... Cam part as cam mechanism, 112 ... Spring member as biasing means.

Claims (8)

A flexible tube, a casing that accommodates a portion of the flexible tube in the flow path, and a rotating shaft in the casing that rotates around the rotating shaft, thereby causing the flow passage intermediate portion to be a first portion. A tube provided with pressing means that sequentially crushes toward the inner wall of the casing by an abutting member, and generates a pressure difference between an upstream portion and a downstream portion with respect to the intermediate portion of the flow path in the flexible tube. In the pump,
The middle part of the flow path is accommodated in the casing so as to draw an arc shape and not having an overlapping part in the direction along the rotation axis,
The pressing means rotates in the normal rotation direction around the rotation axis, whereby a first position where the middle portion of the flow path is located between the first contact member and the inner wall of the casing; Provided between the first abutment member and the inner wall of the casing so as to be alternately located at a second position where the middle portion of the flow path is not located,
Said pressing means, when positioned in the first position, while the flow path of the flexible tube and the non-occluded state when said pressing means, positioned in said second position, said Allowed Choke means for closing the flow path in the middle of the flow path of the flexible tube ,
The pressing means is
A rotating member that rotates about the rotation axis;
A supporting member that supports the first abutting member and is supported with respect to the rotating member such that a distance from the rotation axis of the first abutting member can be changed;
Elastic means interposed between the rotating member and the support member and biasing the support member with an elastic force so that the first contact member supported by the support member is separated from the rotation shaft;
With
The choke means includes
A second abutting member supported by the support member so as to confront the casing with the middle portion of the flow path therebetween,
The second abutting member is configured such that the abutting portion that abuts against the midway portion of the flow path is closer to the rotating shaft than the portion where the first abutting member abuts against the midway portion of the flow path. A tube pump, wherein the tube pump is supported by the support member such that the distance between the two is close .   The tube pump according to claim 1, wherein
  The support member includes a groove formed such that a distance from the rotation shaft decreases in the forward rotation direction.
  The tube pump, wherein the first contact member and the second contact member are supported so as to be movable along the groove with respect to the support member.   The tube pump according to claim 2,
  The first abutting member and the second abutting member are formed by an engaging shaft that engages with the groove, and a cylindrical portion that has the engaging shaft as a central axis,
  The tube pump according to claim 1, wherein the cylindrical portion of the first contact member is formed to have an outer diameter larger than that of the cylindrical portion of the second contact member.   In the tube pump as described in any one of Claims 1-3,
  The tube pump, wherein the second contact member is supported by the support member so as to be adjacent to the rear of the first contact member in a direction along the forward rotation direction.   A flexible tube, a casing that accommodates a portion of the flexible tube in the flow path, and a rotating shaft in the casing that rotates around the rotating shaft, thereby causing the flow passage intermediate portion to be a first portion. A tube provided with pressing means that sequentially crushes toward the inner wall of the casing by an abutting member and generates a pressure difference between an upstream portion and a downstream portion of the flexible tube with respect to the middle portion of the flow path. In the pump,
  The middle part of the flow path is accommodated in the casing so as to draw an arc shape and not having an overlapping part in the direction along the rotation axis,
  The pressing means rotates in the normal rotation direction around the rotation axis, whereby a first position where the middle portion of the flow path is located between the first contact member and the inner wall of the casing; Provided between the first abutment member and the inner wall of the casing so as to be alternately located at a second position where the middle portion of the flow path is not located,
  When the pressing means is located at the first position, the flow path of the flexible tube is unblocked, and when the pressing means is located at the second position, Choke means for closing the flow path in the middle of the flow path of the flexible tube,
  The choke means includes
  A third abutting member facing the first abutting member across the flexible tube when the pressing means is located at the second position;
  Biasing means for biasing the third abutting member toward the flexible tube;
A tube pump characterized by comprising:   The tube pump according to claim 5,
  The rotational movement of the pressing means is converted into a linear movement, and when the pressing means is located at the first position based on the rotational movement of the pressing means, the third abutting member is moved to the biasing force. A tube pump comprising a cam mechanism for pressing in a direction against an urging force by means.   A liquid ejection head that ejects liquid from a nozzle to a target;
  A cap capable of covering the nozzle of the liquid jet head;
In a liquid ejecting apparatus comprising:
  A flexible tube having one end communicating with the cap;
  A casing for accommodating a middle portion of the flow path of the flexible tube;
  A rotating shaft is provided in the casing, and the flow passage intermediate portion is sequentially crushed toward the inner wall of the casing by a first abutting member by rotating around the rotating shaft, and the flexible tube A pressing means for generating a pressure difference between the upstream portion and the downstream portion with respect to the middle portion of the flow path;
A tube pump with
  The middle part of the flow path is accommodated in the casing so as to draw an arc shape and not having an overlapping part in the direction along the rotation axis,
  The pressing means rotates in the normal rotation direction around the rotation axis, whereby a first position where the middle portion of the flow path is located between the first contact member and the inner wall of the casing; Provided between the first abutment member and the inner wall of the casing so as to be alternately located at a second position where the middle portion of the flow path is not located,
  When the pressing means is located at the first position, the flow path of the flexible tube is unblocked, and when the pressing means is located at the second position, Choke means for closing the flow path in the middle of the flow path of the flexible tube,
  The pressing means is
  A rotating member that rotates about the rotation axis;
  A supporting member that supports the first abutting member and is supported with respect to the rotating member such that a distance from the rotation axis of the first abutting member can be changed;
  Elastic means interposed between the rotating member and the support member and biasing the support member with an elastic force so that the first contact member supported by the support member is separated from the rotation shaft;
With
  The choke means includes
  A second abutting member supported by the support member so as to confront the casing with the middle portion of the flow path therebetween,
  The second abutting member is configured such that the abutting portion that abuts against the midway portion of the flow path is closer to the rotating shaft than the portion where the first abutting member abuts against the midway portion of the flow path. The liquid ejecting apparatus is supported by the support member so that the distance between them is close.   A liquid ejection head that ejects liquid from a nozzle to a target;
  A cap capable of covering the nozzle of the liquid jet head;
In a liquid ejecting apparatus comprising:
  A flexible tube having one end communicating with the cap;
  A casing for accommodating a middle portion of the flow path of the flexible tube;
  A rotating shaft is provided in the casing, and the flow passage intermediate portion is sequentially crushed toward the inner wall of the casing by a first abutting member by rotating around the rotating shaft, and the flexible tube A pressing means for generating a pressure difference between the upstream portion and the downstream portion with respect to the middle portion of the flow path;
A tube pump with
  The middle part of the flow path is accommodated in the casing so as to draw an arc shape and not having an overlapping part in the direction along the rotation axis,
  The pressing means rotates in the normal rotation direction around the rotation axis, whereby a first position where the middle portion of the flow path is located between the first contact member and the inner wall of the casing; Provided between the first abutment member and the inner wall of the casing so as to be alternately located at a second position where the middle portion of the flow path is not located,
  When the pressing means is located at the first position, the flow path of the flexible tube is unblocked, and when the pressing means is located at the second position, Choke means for closing the flow path in the middle of the flow path of the flexible tube,
  The choke means includes
  A third abutting member facing the first abutting member across the flexible tube when the pressing means is located at the second position;
  Biasing means for biasing the third abutting member toward the flexible tube;
It is comprised by these, The liquid ejecting apparatus characterized by the above-mentioned.

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