JP4696828B2 - Driving force transmission mechanism, maintenance unit, and liquid ejecting apparatus - Google Patents

Description

  The present invention relates to a driving force transmission mechanism, a maintenance unit, and a liquid ejecting apparatus.

  In general, an ink jet printer (hereinafter simply referred to as “printer”) is widely known as a liquid ejecting apparatus that ejects liquid from a liquid ejecting head to a target. In such a printer, the ink viscosity increases and solidifies due to evaporation of the ink solvent from the nozzle of the recording head as a liquid ejecting head, dust adheres, and air bubbles are clogged, resulting in clogging of the nozzle. It may cause defects. Therefore, a printer is usually provided with a wiping mechanism (maintenance unit) for wiping off ink adhering to the nozzles of the recording head (see, for example, Patent Document 1).

The wiping mechanism includes a driven gear that is always meshed with a drive side gear connected to a drive source and rotates synchronously with the drive side gear, and is frictionally engaged by the urging force of the driven side gear and a compression spring. The toothless gear rotates with the rotation of the driven gear, the cleaner cam that rotates with the rotation of the toothless gear, and the wiper member that moves with the rotation of the cleaner cam. The missing gear is formed at a part of the outer circumferential surface of the outer peripheral surface by rotating by a predetermined angle with the rotation of the driven gear with which the missing gear is frictionally engaged after the start of the wiping operation. The teeth come into mesh with the teeth of the driving gear, and after the meshing, the teeth are rotated by the driving force directly transmitted from the driving gear.
JP 2000-153617 A

  By the way, in such a wiping mechanism in a printer, the frictional force between the driven gear and the missing gear becomes the driving force of the missing gear, while the other side of the surface of the missing gear with respect to the driven gear is in contact with other members. The frictional force between them becomes the deterring force of the toothless gear. For this reason, since the difference in frictional force applied to both sides of the toothless gear becomes the driving force, the frictional force between the driven gear and the toothless gear is different from that of the other member on the opposite surface of the toothless gear with respect to the driven gear. It is necessary to make it sufficiently larger than the frictional force between. However, the intermittent gear is stopped by being locked to a certain member, and thereafter, it does not rotate even if the driven gear rotates. At that time, the sum of the frictional forces on both sides of the intermittent gear becomes a load for driving the driven gear, so increasing the frictional force increases the driving load.

  Further, in an ink jet printer, ink may be scattered when the recording head is wiped by a wiping mechanism. At this time, if the scattered ink enters between the missing gear and the driven gear, the frictional force changes, and the frictional engagement force between the driven gear and the missing gear becomes insufficient and is transmitted from the driving gear. Even if the driven gear is rotated by the driving force, the toothless gear is not rotated with the rotation of the driven gear, and the driving force is not transmitted to the wiper member (and the cleaner cam). Furthermore, when ink adheres to and solidifies with other members on the surface opposite to the driven gear with respect to the driven gear, the frictional force increases, and this frictional force causes the friction between the driven gear and the missing gear. If the force is greater than the force, the toothless gear will not rotate.

  The present invention has been made in view of such circumstances, and a purpose thereof is a driving force transmission mechanism capable of reliably transmitting a driving force while reducing a driving load, and the driving force transmission mechanism. And a liquid ejecting apparatus including the maintenance unit or the driving force transmission mechanism.

  In order to achieve the above object, a driving force transmission mechanism of the present invention includes a driving side gear that rotates around a predetermined axis based on a driving force from a driving source, and the predetermined axis line that is always meshed with the driving side gear. A driven gear that rotates around a specific axis parallel to the drive gear and the drive gear that has an intermittent meshing relationship, and an intermittent gear that rotates around the specific axis adjacent to the driven gear And an interlocking member that rotates together with the driven side gear by engaging with the driven side gear so as to be able to transmit power, and disposes the intermittent gear between the driven side gear, the driven side gear, and By biasing at least one of the interlocking members toward the other, the intermittent gear and the driven gear, and the biasing member that frictionally engages the partial gear and the interlocking member, The spur gear is in mesh with the drive gear. Wherein in a state in which no partial gear and the driven gear, and, after rotating by frictional engagement with the interlocking member and the toothless gear, and a stopper mechanism for rotating stopping the partial gear.

  According to this configuration, the toothless gear is sandwiched between the driven gear that rotates synchronously with the drive gear and the interlocking member that rotates together with the driven gear by being engaged with the driven gear so as to transmit power. It becomes. For this reason, compared with the case where it arrange | positions in the state contact | abutted to the member which is not a rotary body like the flange part etc. of a support shaft, for example, the sliding contact resistance at the time of rotation is reduced, and the driven gear side The rotation of the gear can be reliably transmitted to the toothless gear. In addition, since a frictional engagement force can be obtained at the contact surface between the toothless gear and the interlocking member, the biasing force of the biasing member that frictionally engages the toothless gear and the driven gear can be reduced. Furthermore, after the intermittent gear is stopped by the stopper mechanism, only the driven gear and the interlocking member rotate, and the driving load temporarily increases. Since the biasing force of the member is small, an increase in driving load can be suppressed as much as possible.

In the driving force transmission mechanism of the present invention, the driven gear is formed with a first insertion hole that penetrates in the axial direction of the specific axis, and the segmented gear penetrates in the axial direction of the specific axis. A second insertion hole is formed, and the interlocking member is connected to the first insertion hole and the second insertion hole, and is connected to the shaft part. And a flange that abuts against a surface opposite to the surface facing the gear.
In the driving force transmission mechanism of the present invention, a convex portion that protrudes toward the inner peripheral side of the first insertion hole is formed on the inner peripheral surface of the first insertion hole, and the outer periphery of the shaft portion includes the A groove is formed to engage with the protrusion.
The driving force transmission mechanism of the present invention includes a load-side driven member that interlocks with the tooth-missing gear by being engaged with the tooth-missing gear so as to be able to transmit power, the driving-side gear and the driving gear from the driving source. After the interlocking member starts to rotate, the load-side gear rotates after the intermittent gear rotates from a state having no meshing relationship with the driving gear to a state having a meshing relationship with the rotation of the driven gear. A locking mechanism for locking the driven member and the toothless gear is further provided.

  According to this configuration, the load side driven after the intermittent gear rotates from the state having no meshing relationship with the driving side gear to the state having the meshing relationship with the rotation of the driven side gear and the interlocking member. The member and the toothless gear are locked. Therefore, during driving, the load on the load side driven member is not applied to the drive source side, so that the drive load can be reduced. In addition, the driven gear that always rotates in mesh with the drive side gear is frictionally engaged with the missing gear by the biasing force of the biasing member, so that the missing gear is rotated along with the rotation. Since the driving load is reduced, the driving force can be reliably transmitted to the toothless gear.

  The locking mechanism in the driving force transmission mechanism of the present invention includes a first locking portion provided on the toothless gear so as to draw a turning locus centered on the specific axis along with the rotation of the toothless gear. And a second locking portion provided on the load side driven member so as to be positioned on the rotation locus of the first locking portion, wherein the locking gear is configured such that the partial gear is the driving side gear. It is set as the structure locked after rotating to the state which has a meshing relationship.

  According to this structure, when the 1st latching | locking part provided in the partial-tooth gear rotates with the rotation of a partial-tooth gear, the load side follower located on the rotation locus | trajectory of the said 1st latching | locking part It latches in the 2nd latching | locking part provided in the member. Therefore, it is possible to easily realize a configuration in which the missing tooth gear and the load side driven member are locked after the missing tooth gear rotates from the state having no meshing relationship with the drive side gear to the state having the meshing relationship.

  One locking portion of the first locking portion and the second locking portion in the driving force transmission mechanism of the present invention is a locking projection, and the other locking portion is provided with the other locking portion. It is a long hole-shaped or long hole-shaped locking recess formed on the load-side driven member or the toothless gear so as to follow the rotation locus of the locking protrusion.

  According to this configuration, if the locking convex portion is in the engaged state in the locking concave portion, the locking convex portion slides in the long hole-shaped or long hole-shaped locking concave portion, so that the long hole In this case, the tooth-missing gear and the load side driven member can be locked when hitting the end of the locking recess having the shape of a hole or a long hole. According to this, the missing gear and the load-side driven member can be arranged close to (contact), and the entire apparatus configuration can be made compact.

  A maintenance unit according to the present invention includes the driving force transmission mechanism and a moving member that moves up and down with respect to a nozzle forming surface of a liquid ejecting head that ejects liquid, and is driven from a driving source via the driving force transmission mechanism. Force is transmitted to the moving member.

  According to this configuration, it is possible to reduce the driving load when the moving member is moved up and down with respect to the nozzle formation surface of the liquid jet head, and it is possible to reliably transmit the driving force to the moving member.

The liquid ejecting apparatus according to the aspect of the invention includes the driving force transmission mechanism and the liquid ejecting head.
According to this configuration, even when the liquid ejected from the liquid ejecting head is scattered around the missing gear in the driving force transmission mechanism, the missing gear is reliably rotated by frictional engagement with the driven gear and the interlocking member. Can be made.

According to another aspect of the invention, a liquid ejecting apparatus includes the maintenance unit and a liquid ejecting head that ejects liquid.
According to this configuration, when the moving member is moved up and down with respect to the nozzle formation surface of the liquid ejecting head, it can be configured as a liquid ejecting apparatus that can reduce the driving load and reliably transmit the driving force.

Hereinafter, an embodiment in which the present invention is embodied in an on-carriage type printer will be described with reference to FIGS.
As shown in FIG. 1, a printer 10 as a liquid ejecting apparatus according to the present embodiment has a frame 11 having a substantially box shape, and a lower portion in the frame 11 has a longitudinal direction (see FIG. 1). A platen 12 is installed along the X direction. The platen 12 is a support for supporting the paper P as a target, and based on the driving force of the paper feed motor 14 included in the paper feed mechanism 13, the platen 12 has a sub-operation direction orthogonal to the X direction as the main scanning direction. It feeds along the Y direction. In the following description, the side to which the paper P is fed is the front side, and the left-right direction when viewed from the front side is the left-right direction.

  A guide shaft 15 is installed above the platen 12 in the frame 11, and a carriage 16 is inserted and supported on the guide shaft 15. A driving pulley 17 and a driven pulley 18 are rotatably supported at positions corresponding to both end portions of the guide shaft 15 on the inner surface of the frame 11. A carriage motor 19 is connected to the drive pulley 17, and a timing belt 20 that fixes and supports the carriage 16 is hung between the pair of pulleys 17 and 18. Therefore, the carriage 16 is movable in the main scanning direction X via the timing belt 20 by driving the carriage motor 19 while being guided by the guide shaft 15.

  As shown in FIG. 1, a recording head 21 as a liquid ejecting head is provided on the lower surface side of the carriage 16. A plurality of nozzles (not shown) are formed on the lower surface side of the recording head 21, and piezoelectric elements (not shown) are arranged in the recording head 21 so as to individually correspond to the nozzles. Then, by driving and controlling each piezoelectric element, ink (liquid) is ejected from each nozzle toward the paper P reaching the lower side of the recording head 21.

  In addition, ink cartridges 23 and 24 for supplying ink to the recording head 21 are detachably mounted on the carriage 16. An ink storage chamber (not shown) is formed in each of the ink cartridges 23 and 24, and ink is stored in each of the ink storage chambers.

  Further, as shown in FIG. 1, a waste liquid tank 27 is provided below the platen 12 in the frame 11 so as to extend in parallel with the platen 12. The waste liquid tank 27 contains an absorbing member (not shown) made of, for example, porous pulp material. Therefore, at the time of well-known cleaning, flushing, and wiping, the ink is discharged to the waste liquid tank 27 and absorbed by the absorbing member. On the other hand, a maintenance unit 30 is provided at one end of the printer 10 (the right end in FIG. 1), that is, in the non-ejection area where the paper P does not reach.

  The maintenance unit 30 has a wiper member 31 and a cap 32 at the upper part thereof, and performs a capping function for sealing the nozzle forming surface 21a of the recording head 21 when printing is stopped, and a suction operation for appropriately sucking ink from the nozzles. It has a cleaning function to prevent nozzle clogging. In addition, the nozzle forming surface 21a of the recording head 21 is wiped to have a wiping function for adjusting the meniscus of the ink in the nozzle and removing excess ink.

  FIG. 2 is a front sectional view of a main part of the maintenance unit 30 and particularly shows the configuration of the wiping mechanism. The details of the maintenance unit 30 will be described below with reference to FIGS. As shown in FIG. 2, the maintenance unit 30 includes a casing 33 as a main body case formed in a box. Inside the casing 33, a pump drive mechanism (not shown) for driving a suction pump (not shown) at the time of cleaning, a cap raising / lowering mechanism (not shown) for raising and lowering the cap 32, and a drive for raising and lowering the wiper member 31 are provided. A wiper lifting mechanism 34 as a force transmission mechanism is accommodated. Further, a drive motor 36 is accommodated as a drive source for generating a drive force for driving each mechanism.

  A first gear 37 is fixed to the drive shaft 36 a of the drive motor 36. The first gear 37 is meshed with a second gear 38 serving as a drive-side gear rotatably provided on a shaft portion 33c provided on the lower case 33b. And the drive motor 36 raises the wiper member 31 by rotating forward (rotating in the direction shown by the arrow in FIG. 2) as described later, or descends the wiper member 31 by rotating backward. A driving force is transmitted to the wiper lifting mechanism 34. Furthermore, the drive motor 36 transmits a driving force to the pump drive mechanism and the cap lifting mechanism (both not shown) via the first gear 37. In addition, the wiper member 31 in this embodiment is comprised from flexible members, such as an elastomer, and the upper end part is formed in the hook shape curved in the direction in alignment with the X direction in FIG.

Next, the configuration of the wiper lifting mechanism 34 will be described with reference to FIG. FIG. 3 is an exploded perspective view for explaining the configuration of the wiper lifting mechanism 34.
As shown in FIG. 3, a columnar shaft portion 41 is formed to protrude from the lower surface of the upper case 33 a (surface opposite to the lower case). The wiper lifting mechanism 34 includes a washer 42, a coil spring 43 as an urging member, a spur gear 44 as a driven side gear, a toothless gear 45, a bush 46 with a hook as an interlocking member, and a cylindrical cam 47 as a load side driven member. I have. Then, a washer 42, a coil spring 43, a spur gear 44, a spur gear 45, a hooked bush 46, and a cylindrical cam 47 are inserted through the shaft portion 41 in this order from the upper case 33a side. To be precise, the toothless gear 45 is fitted on the outer periphery of the shaft portion 53 of the flanged bush 46.

  The washer 42 is formed in a disk shape, and a through hole 48 is formed in the center thereof. The washer 42 is rotatably inserted into the shaft portion 41 through the through hole 48, and comes into contact with the upper case 33a when inserted.

  Next, the coil spring 43 is inserted into the shaft portion 41 so that one end thereof is in contact with the washer 42 inserted through the shaft portion 41. A spur gear 44 is inserted through the shaft portion 41 so as to compress the coil spring 43. The spur gear 44 has teeth 44 a formed on the outer peripheral surface thereof over the entire circumference, and is always in mesh with the second gear 38. As a result, when the drive motor 36 rotates forward and backward, the spur gear 44 rotates in the same direction as the drive motor 36 via the second gear 38. Further, as the spur gear 44 rotates, the coil spring 43 compressed by the spur gear 44 and the washer 42 pressed against the coil spring 43 also rotate about the shaft portion 41.

  On the other hand, an insertion hole 51 is formed through the central portion of the spur gear 44 in the direction of the axis c. A contact convex portion 50 having an outer circular shape protruding downward is formed on the lower surface side of the spur gear 44. On the other hand, a convex portion 52 protruding toward the inner peripheral side is formed on the inner peripheral surface below the insertion hole 51 so as to be symmetric with respect to the axis c. The shaft portion 53 of the flanged bush 46 is inserted into the insertion hole 51. The bush 46 with the flange is disposed in a posture where the flange portion 54 faces the lower case 33b. A key groove 55 that engages with the convex portion 52 of the spur gear 44 is formed on the outer periphery of the shaft portion 53 of the flanged bush 46 so as to be symmetrical with respect to the axis c so as to extend in the direction of the axis c. Yes. Therefore, at the time of assembly, the convex portion 52 of the spur gear 44 is engaged with the key groove 55 of the bushed bush 46 and the outer periphery of the shaft portion 53 of the bushed bush 46 is in contact with the inner periphery of the insertion hole 51. The spur gear 44 and the flanged bush 46 are rotated together.

  The toothless gear 45 has a tooth portion 45a formed on a part of its outer peripheral surface. The tooth portion 45a can mesh with the second gear 38. The tooth portion 45a of the missing gear 45 and the tooth portion 38a of the second gear 38 are engaged with each other or released from the engagement as the missing gear 45 rotates. An insertion hole 56 is formed through the center portion of the partial gear 45 in the direction of the axis c, and the shaft portion 53 of the hooked bush 46 is inserted into the insertion hole 56.

  That is, the toothless gear 45 is externally fitted to the shaft portion 53 of the flanged bush 46 and is disposed between the spur gear 44 and the flange portion 54 of the flanged bush 46. Then, when the spur gear 44 is urged toward the partial gear 45 by the coil spring 43, the lower surface 45 c of the partial gear 45 comes into contact with the upper surface 54 a of the flange portion 54 of the flanged bush 46. Further, the inner peripheral surface 56 a in the insertion hole 56 portion of the partial gear 45 is in contact with the outer peripheral surface 53 a of the shaft portion 53 of the flanged bush 46. Furthermore, the upper surface 45b of the toothless gear 45 is in contact with the lower surface 44b of the spur gear 44 (corresponding to the lower surface of the contact protrusion 50). That is, in the assembled state, the toothless gear 45 is in contact with the rotating body (spur gear 44, hooked bush 46). Furthermore, a long hole 57 as a locking concave portion (first locking portion) formed in a long hole shape extending along the circumferential direction is formed in the segment gear 45 in the direction of the axis c. As shown in FIG. 5, the long hole 57 forms a central angle θ2.

  On the other hand, an insertion hole 58 is formed through the central portion of the cylindrical cam 47 having a thick cylindrical shape in the direction of the axis c, and the shaft portion 41 is inserted through the insertion hole 58. Further, a pin 59 as a columnar locking projection (second locking portion) is formed on the upper surface of the cylindrical cam 47 so as to protrude upward, and engages in the elongated hole 57 of the toothless gear 45. It is like that.

  Accordingly, the toothless gear 45 rotates forward (rotates in the direction indicated by the arrow in FIG. 3), and the pin 59 contacts and locks with the first locking end 60 that is one circumferential end of the elongated hole 57. In this state, the cylindrical cam 47 rotates with the forward rotation of the toothless gear 45. On the other hand, when the toothless gear 45 rotates in the reverse direction and the pin 59 is brought into contact with and locked to the second locking end 61 which is the other circumferential end of the elongated hole 57, the cylindrical cam 47 is moved to the missing tooth. It rotates with the reverse rotation of the gear 45. Thus, in this embodiment, the pin 59 is always engaged in the long hole 57, and the lower surface 45c of the partial gear 45 and the upper surface of the cylindrical cam 47 contact | abut. However, the pin 59 is not in contact with and locked to the first locking end 60 of the elongated hole 57 when the segment gear 45 is rotating forward or when the segment gear 45 is rotating backward. In a state where the pin 59 is not in contact with and locked to the second locking end portion 61 of the long hole 57, the cylindrical cam 47 does not rotate even if the toothless gear 45 rotates. The long hole 57 and the pin 59 constitute the locking mechanism 62 of the present invention.

  Further, a groove portion 63 is recessed in the peripheral side surface of the cylindrical cam 47. The groove part 63 is for raising and lowering the wiper member 31, and a lever 64 attached to the wiper member 31 is inserted into the groove part 63 as shown in FIG. Then, when the cylindrical cam 47 rotates forward about the shaft portion 41 due to the positive rotation of the toothless gear 45, the lever 64 is guided by the groove portion 63 and rises in the direction of the central axis c of the shaft portion 41. Accordingly, as shown in FIG. 2, the wiper member 31 is raised in the direction of the arrow U and is held at a height for wiping and cleaning the nozzle forming surface 21a of the recording head 21. On the other hand, when the cylindrical cam 47 rotates reversely about the shaft 41 due to the reverse rotation of the toothless gear 45, the lever 64 is guided by the groove 63 and descends in the direction of the central axis c. As a result, the wiper member 31 is lowered in the direction of the opposite arrow U and is separated from the nozzle forming surface 21 a of the recording head 21.

  A cam-side pin 65 is formed on the outer peripheral surface of the cylindrical cam 47 so as to protrude radially outward. Then, after the cylindrical cam 47 rotates by a predetermined angle, the cam side pin 65 is locked to the case side pin 66 formed to protrude in the casing 33, so that the rotation of the cylindrical cam 47 beyond the predetermined angle is restricted. It is like that. That is, the stopper mechanism 67 of the present invention is constituted by the cam side pin 65 formed on the cylindrical cam 47 and the case side pin 66 fixedly provided in the casing 33.

  Next, the operation of the maintenance unit 30 of the printer 10 described above will be described below with particular attention paid to the wiping operation. In the state at the start of the wiping operation, as shown in FIG. 5, the tooth portion 45a of the missing gear 45 and the tooth portion 38a of the second gear 38 are not engaged with each other, and the missing gear 45 rotates forward. The rotation angle until the tooth portion 45a meshes with the tooth portion 38a of the second gear 38 (rotated in the direction indicated by the arrow in FIG. 3) is in the state of angle θ1. The pin 59 of the cylindrical cam 47 is in contact with the second locking end 61 of the long hole 57. The angle θ1 is set smaller than the central angle θ2 at which the long hole 57 is formed. First, the printer 10 drives the carriage motor 19 to move the carriage 16 in the X direction shown in FIG. 1 and arranges the carriage 16 at a maintenance position facing the cap 32 of the maintenance unit 30.

  In this arrangement state, the operation of moving the wiper member 31 from the standby position to the wiping position is performed. First, when the drive motor 36 is driven to rotate forward, the first gear 37 rotates, and the second gear 38 and the spur gear 44 rotate accordingly. Then, the flanged bush 46 that is integrally engaged with the spur gear 44 rotates as the spur gear 44 rotates. At this time, the spur gear 44 is urged toward the partial gear 45 by the coil spring 43. Therefore, between the lower surface 45 c of the toothless gear 45 and the upper surface 54 a of the flange portion 54 of the flanged bush 46, the outer peripheral surface of the inner peripheral surface 56 a in the insertion hole 56 portion of the edgeless gear 45 and the shaft portion 53 of the flanged bush 46. A frictional force is generated between the surface 53 a and between the upper surface 45 b of the toothless gear 45 and the lower surface 44 b of the spur gear 44. As a result, the toothless gear 45 rotates forward by the frictional engagement force as the spur gear 44 rotates. That is, in this state, since the tooth portion 45a of the toothless gear 45 and the tooth portion 38a of the second gear 38 are not in mesh with each other, the rotation of the second gear 38 is directly transmitted to the toothless gear 45. However, the spur gear 45 rotates synchronously with the rotation of the spur gear 44.

  When the toothless gear 45 rotates by an angle θ1, the tooth portion 45a of the toothless gear 45 and the tooth portion 38a of the second gear 38 mesh with each other. By being directly transmitted to the tooth gear 45, the toothless gear 45 continues to rotate forward. Note that the pin 59 of the cylindrical cam 47 that engages with the elongated hole 57 of the intermittent gear 45 during rotation of the angle θ1 until the intermittent gear 45 and the second gear 38 mesh with each other is in the elongated hole 57. Is moved so as to slide toward the first locking end portion 60 side. In practice, the pin 59 (cylindrical cam 47) is rotating only in the positive gear 45 while maintaining the relative position to the second gear 38.

  Here, since the angle θ1 is set to be smaller than the central angle θ2 at which the elongated hole 57 is formed, the tooth portion 45a of the toothless gear 45 is provided before the pin 59 is locked to the first locking end portion 60. And the tooth portion 38a of the second gear 38 mesh with each other. That is, after the tooth portion 45a of the toothless gear 45 and the tooth portion 38a of the second gear 38 mesh with each other and rotation is transmitted directly from the second gear 38 to the toothless gear 45, the pin 59 is locked to the first locking end 60. Then, after the pin 59 is locked to the first locking end portion 60, the cylindrical cam 47 is rotated forward with the rotation of the toothless gear 45. As described above, the power of the toothless gear 45 is transmitted to the cylindrical cam 47 after the start of rotation of the toothless gear 45.

  Therefore, when the intermittent gear 45 is rotated by the angle θ1 due to the frictional engagement force with the spur gear 44 (the flanged bush 46) when the motor is driven, the drive motor 36 is loaded only by the intermittent gear 45. The cylindrical cam 47 and the wiper member 31 are not loaded.

  Next, when the cylindrical cam 47 rotates along with the rotation of the toothless gear 45, the lever 64 is guided by the groove 63 and moves up in the direction of the central axis c of the shaft 41. At this time, although the load for driving the cylindrical cam 47 is increased, the toothless gear 45 and the second gear 38 are engaged with each other by rotating more than the angle θ1, and the toothless gear 45 can be rotated. As a result, as shown in FIG. 2, the wiper member 31 rises in the direction of arrow U to a height at which the nozzle forming surface 21 a of the recording head 21 can be wiped and cleaned, and the lever 64 reaches the flat portion of the groove 63 of the cylindrical cam 47. Therefore, the wiper member 31 is held at a height for wiping and cleaning the nozzle forming surface 21a of the recording head 21. When the wiper member 31 is raised to this height, the meshing between the missing gear 45 and the second gear 38 is released. Further, at this time, the positive rotation of the cylindrical cam 47 is regulated by the cam side pin 65 protruding from the outer peripheral surface being locked to the case side pin 66 protruding from the casing 33. It has become. Thereby, the rotation of the toothless gear 45 engaged with the cylindrical cam 47 is also restricted. After that, the first gear 37 continues to rotate in order to drive the pump drive mechanism and the cap lifting mechanism, so that the spur gear 44 also rotates. However, since the rotation of the toothless gear 45 is restricted, the spur gear 44 is rotated around. It does not rotate.

  In this state, the printer 10 moves the carriage 16 arranged at a position facing the cap 32 of the maintenance unit 30 in the anti-X direction shown in FIG. At this time, the nozzle forming surface 21a of the recording head 21 is in contact with the tip of the wiper member 31 at the wiping position. For this reason, when the carriage 16 is moved in the anti-X direction, the nozzle forming surface 21 a of the recording head 21 slides on the wiper member 31. At this time, the ink attached to the nozzle forming surface 21 a of the recording head 21 is wiped off by the wiper member 31.

  When the scanning of the carriage 16 is completed, the operation of moving the wiper member 31 from the wiping position to the original standby position is then performed. As described in detail above, an operation opposite to that performed when moving from the standby position to the wiping position is performed.

  That is, first, when the drive motor 36 is driven in the reverse direction, the first gear 37 rotates, and accordingly, the second gear 38 and the spur gear 44 rotate. At this time, the hooked bush 46 integrally engaged with the spur gear 44 rotates as the spur gear 44 rotates. Similarly to the forward rotation, the driving force is transmitted to the toothless gear 45 through the spur gear 44 by the frictional engagement force between the spur gear 44 and the flanged bush 46. The toothless gear 45 rotates little by little with the rotation of the spur gear 44 and eventually meshes with the second gear 38. Then, after the pin 59 is locked to the second locking end portion 61, the cylindrical cam 47 rotates in reverse with the rotation of the toothless gear 45. As a result, the wiper member 31 is lowered and separated from the nozzle forming surface 21 a of the recording head 21. After the toothless gear 45 and the second gear 38 are not engaged with each other, the toothless gear 45 is rotated by the frictional engagement force between the spur gear 44 and the flanged bush 46 and then, similarly to the above, by the stopper mechanism 67. The rotation of the cylindrical cam 47 is restricted, and the rotation of the toothless gear 45 is also restricted, so that the spur gear 44 idles without the toothless gear 45.

According to the embodiment described above, the following effects can be obtained.
(1) In the above embodiment, when the motor is driven, the pin 59 and the first locking end portion 60 are separated from each other in the long hole 57. When the toothless gear 45 rotates by the angle θ1 due to the frictional engagement force with the spur gear 44 (the bush 46), the drive motor 36 is loaded only with the toothless gear 45, and the cylindrical cam 47, the wiper member 31, etc. are not loaded. For this reason, the drive load of the drive motor 36 can be reduced.

  (2) In the above-described embodiment, the toothless gear 45 and the cylindrical cam 47 are missing because the pin 59 is locked to the first locking end 60 (or the second locking end 61) in the long hole 57. A force is transmitted from the toothed gear 45 to the cylindrical cam 47. As a result, the load of the cylindrical cam 47 and the wiper member 31 is applied to the drive motor 36 because the pin 59 of the cylindrical cam 47 is connected to the first locking end 60 (or the second engagement portion) of the elongated hole 57 in the intermittent gear 45. This is because the toothless gear 45 and the cylindrical cam 47 are in the power transmission state by being locked to the stop end portion 61). At this time, the toothless gear 45 and the second gear 38 are already meshed with each other, so that the drive motor 36 is not driven by the second gear 38 but by the frictional force between the toothless gear 45 and the spur gear 44. Since the driving force is directly transmitted to the toothless gear 45, the power can be reliably transmitted to the cylindrical cam 47.

  (3) In the above-described embodiment, the pin 59 is engaged in the long hole 57, and the pin 59 is connected to the first locking end 60 or the first of the long hole 57 as the segment gear 45 rotates in a predetermined direction. 2 It is the structure latched with the latching end part 61. FIG. According to this, it can arrange | position in the state which made the cylindrical cam 47 and the toothless gear 45 approach (contact | abut), and can make the whole apparatus compact.

  (4) In the above embodiment, the flanged bush 46 that rotates integrally with the spur gear 44 is provided. The toothless gear 45 is externally fitted to the flanged bush 46 and is energized so as to be sandwiched between the spur gear 44 and the flanged bush 46, so that the rotating body (spur gear) is rotated in the rotation start state. 44, which is in contact only with the bush 46). Therefore, compared to the case where the toothless gear 45 is arranged in contact with a member that is not a rotating body, the sliding contact resistance during rotation is reduced, and the spur gear 44 is reliably rotated. 45 can be transmitted.

  Further, in the rotation start state, since the missing gear 45 is not engaged with any other member other than the spur gear 44 and the flanged bush 46, it is sufficient that there is enough force to rotate the missing gear 45. Then, on the contact surface between the toothless gear 45 and the flanged bush 46 (the outer peripheral surface 53a of the shaft portion 53, the upper surface 54a of the flange portion 54) and the contact surface with the spur gear 44 (the lower surface 44b of the spur gear 44). Since a frictional engagement force is obtained, the biasing force of the coil spring 43 that frictionally engages the toothless gear 45 and the spur gear 44 can be reduced. As a result, even when the spur gear 44 idles with respect to the intermittent gear 45, the increase in load due to the frictional force is small. Furthermore, since the load for driving the toothless gear 45 at the start of rotation can be small, even if ink adheres between the spur gear 44 and the toothless gear 45 or between the toothless gear 45 and the hooked bush 46, the load is insufficient. The tooth gear 45 can be rotated. Even when the attached ink is solidified and the spur gear 44 and the toothless gear 45 are stuck, the toothless gear 45 is stopped by the stopper mechanism 67 via the cylindrical cam 47, and the spur gear 44 is moved to the second gear. When driven through 38, it can be peeled off by a driving force.

  (5) In the above embodiment, the contact convex portion 50 is formed on the lower surface side of the spur gear 44 to reduce the contact area with the toothless gear 45. On the other hand, the increase in load due to the frictional force when idling can be minimized.

The above embodiment may be changed to another embodiment (another example) as follows.
In the above embodiment, the long hole 57 may be configured as a recess provided in a groove shape (hole shape) on the lower surface 44 b of the spur gear 44.

  In the above embodiment, the locking mechanism 62 configured by the long hole 57 and the pin 59 may be configured such that a pin is provided on the toothless gear 45 side and a long hole is provided on the cylindrical cam 47 side. In addition, it is good also as a combination of a convex part (1st latching | locking part) and a convex part (2nd latching | locking part). Even in this case, a convex portion is provided on one of the toothless gear 45 and the cylindrical cam 47, and a convex portion is provided on the other so as to be positioned on the rotation locus of the convex portion. Since it can be set as the structure which each convex part latches at the time of rotation, there can exist an effect similar to the effect (1) in the said embodiment, (2), (4).

  In the above-described embodiment, the locking mechanism 62 constituted by the long hole 57 and the pin 59 is configured such that after the partial gear 45 and the second gear 38 have a meshing relationship, the partial gear 45 and the cylindrical cam 47 It is good also as a structure which provides the clamp member which clamps to one of the missing gear 45 and the cylindrical cam 47. FIG.

  In the above embodiment, the coil spring is used as the urging member. However, the spring member is not limited to this, and may be another spring member such as a disc spring or an elastic member such as rubber as long as it can be urged.

-In the said embodiment, you may materialize this invention as a drive force transmission mechanism at the time of raising / lowering the cap 32 (moving member).
In the above embodiment, a cam portion that protrudes outward in the radial direction, for example, is provided at a portion where the tooth portion 45a of the toothless gear 45 is not formed, and the cam portion and the wiper member 31 are directly locked. Thus, the wiper member 31 may be configured to move up and down. In this case, it is not necessary to provide the cylindrical cam 47, and the number of members can be reduced. In this embodiment, the wiper member 31 that functions as a moving member functions as a load-side driven member.

  In the above-described embodiment, the contact convex portion 50 of the spur gear 44 may not be formed, and the spur gear 44 may be configured to abut on the entire lower surface of the spur gear 44. Alternatively, the contact area with the toothless gear 45 can be adjusted by appropriately adjusting the size of the contact protrusion 50. Similarly, the flange portion 54 of the flanged bush 46 and the toothless gear 45 may be configured to abut on the entire lower surface of the toothless gear 45, or by appropriately adjusting the size of the flange portion 54. The contact area between the flange 54 and the toothless gear 45 can be adjusted.

  In the above embodiment, the ink cartridges 23 and 24 are embodied in an on-carriage type ink jet printer mounted on the carriage 16, but the present invention is not limited thereto, and may be embodied in an off-carriage type ink jet printer.

  In the above embodiment, the printer 10 that ejects ink has been described as the liquid ejecting apparatus, but other liquid ejecting apparatuses may be used. For example, printing apparatuses including fax machines, copiers, etc., liquid ejecting apparatuses that eject liquids such as electrode materials and coloring materials used in the production of liquid crystal displays, EL displays, and surface-emitting displays, and bio-organic materials used in biochip manufacturing It may be a liquid ejecting apparatus for ejecting a liquid or a sample ejecting apparatus as a precision pipette. Also, the liquid is not limited to ink, and may be applied to other liquids.

The technical ideas that can be grasped from the above embodiment and other examples will be described below.
A driving side gear that rotates around a predetermined axis based on a driving force from a driving source, a driven side gear that always meshes with the driving side gear and rotates around a specific axis parallel to the predetermined axis; A drive-side gear has an intermittent meshing relationship, and has at least one of a tooth-missing gear that rotates around the specific axis adjacent to the driven-side gear, and the tooth-missing gear and the driven-side gear. A biasing member that frictionally engages the toothless gear and the driven gear by biasing toward the other side, and rotates together with the toothless gear by engaging the toothless gear so that power can be transmitted. A load-side driven member, and a bushed bush that is provided integrally with the driven-side gear and rotates about the specific axis, and the toothless gear is externally fitted to a shaft portion of the bushed bush. And the urging member A driving force transmission mechanism characterized in that one end side is disposed between a flange portion of the flanged bush and the driven gear so that the flange portion of the flanged bush comes into contact with the flange portion.

  According to this technical idea, the toothless gear is externally fitted to a flanged bush that rotates integrally with the driven gear, and one end side abuts on the flange. For this reason, compared with the case where it arrange | positions in the state contact | abutted to the member which is not a rotary body, sliding contact resistance is reduced and rotation of a driven side gear can be reliably transmitted to a non-tooth gear. In addition, since a frictional force is obtained at the contact surface (shaft portion, flange portion) between the toothless gear and the flanged bush, the biasing force of the biasing member that frictionally engages the toothless gear and the driven gear is small. The effect is

1 is an overall perspective view of a printer as a liquid ejecting apparatus according to an embodiment. The principal part front sectional view of a maintenance unit. The exploded perspective view of a wiping mechanism. FIG. 3 is a front sectional view of a portion surrounded by a two-dot chain line in FIG. 2. The figure for demonstrating the meshing aspect of a 2nd gearwheel and a non-toothed gear.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Inkjet printer as a liquid ejecting apparatus, 21 ... Recording head as a liquid ejecting head, 21a ... Nozzle formation surface, 30 ... Maintenance unit, 31 ... Wiper member as a moving member, 32 ... Cap, 34 ... Transmission of driving force A wiping mechanism as a mechanism, 36: a drive motor as a drive source, 38 ... a second gear as a drive side gear, 43 ... a coil spring as a biasing member, 44 ... a spur gear as a driven side gear, 45 ... a missing gear , 46 ... bush with bush as interlocking member, 47 ... cylindrical cam as load side driven member, 57 ... long hole as first locking part and locking recess, 59 ... second locking part and locking convex part As a pin, 62 ... a locking mechanism, 67 ... a stopper mechanism, a ... a predetermined axis, c ... a specific axis.

Claims (9)

A driving side gear that rotates around a predetermined axis based on a driving force from a driving source;
A driven gear that always meshes with the driving gear and rotates around a specific axis parallel to the predetermined axis;
The drive side gear has an intermittent meshing relationship, and the toothless gear that rotates around the specific axis adjacent to the driven side gear;
An interlocking member that rotates together with the driven gear by engaging with the driven gear so as to be able to transmit power, and that disposes the intermittent gear between the driven gear,
By urging at least one of the driven gear and the interlocking member toward the other, the intermittent gear and the driven gear, and the intermittent gear and the interlocking member are frictionally engaged. A force member;
After the partial gear is rotated by frictional engagement between the partial gear and the driven gear and the partial gear and the interlocking member in a state where the partial gear does not have a meshing relationship with the driving gear, the partial gear is rotated. A driving force transmission mechanism comprising a stopper mechanism for stopping rotation of the toothed gear.   The driven gear is formed with a first insertion hole penetrating in the axial direction of the specific axis,
  A second insertion hole penetrating in the axial direction of the specific axis is formed in the partial gear,
  The interlocking member is
  A shaft portion inserted through the first insertion hole and the second insertion hole;
  A collar portion connected to the shaft portion and abutting against a surface of the segmented gear opposite to the surface facing the driven gear;
  The driving force transmission mechanism according to claim 1, comprising:   On the inner peripheral surface of the first insertion hole, a convex portion protruding to the inner peripheral side of the first insertion hole is formed, and
  The driving force transmission mechanism according to claim 2, wherein a groove portion that engages with the convex portion is formed on an outer periphery of the shaft portion. A load-side driven member that is interlocked with the segmented gear by locking the segmented gear so that power can be transmitted;
After the driving side gear starts to rotate by the driving force from the driving source, the intermittent gear does not have a meshing relationship with the driving side gear as the driven gear and the interlocking member rotate. The rotation mechanism according to any one of claims 1 to 3, further comprising a locking mechanism that locks the load side driven member and the toothless gear after rotating to a state having a meshing relationship. The driving force transmission mechanism described. The locking mechanism includes a first locking portion provided on the toothless gear so as to draw a turning locus centered on the specific axis along with the rotation of the toothless gear, A second locking portion provided on the load-side driven member so as to be positioned on the rotation locus, and the locking portions are in a state where the intermittent gear has a meshing relationship with the drive-side gear. The driving force transmission mechanism according to claim 4 , wherein the driving force transmission mechanism is configured to be locked after being rotated. One locking portion of the first locking portion and the second locking portion is a locking convex portion, and the other locking portion is a load side driven member or a missing tooth provided with the other locking portion. The driving force transmission mechanism according to claim 5 , wherein the driving force transmission mechanism is an elongated hole-shaped or elongated hole-shaped locking recess formed along the rotation locus of the locking protrusion on the gear. A driving force transmission mechanism according to any one of claims 1 to 6 and a moving member that moves up and down with respect to a nozzle formation surface of a liquid ejecting head that ejects liquid. A maintenance unit characterized in that a driving force from a driving source is transmitted to the moving member. A liquid ejecting apparatus comprising: the driving force transmission mechanism; and a liquid ejecting head for ejecting liquid in any one of claims 1-6. A liquid ejecting apparatus comprising: the maintenance unit according to claim 7; and a liquid ejecting head that ejects liquid.

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