WO2007026471A1 - Medium carrying mechanism and recording device - Google Patents

Abstract

A medium carrying mechanism (3), comprising a rotatable carrying roller, a roughly cylindrical carrying roller carrying a recording medium by rotating together with the carrying roller while holding the recording medium therebetween, a support unit supporting the carrying roller on the peripheral surface of the carrying roller so as to be brought into contact with and separated from each other, and an operation unit moving the carrying rollers according to the movement of an operation part. The carrying roller is disposed at a position apart from the carrying roller in such a state that the operation part is disposed at a first position, the carrying roller is pressed against the peripheral surface of the carrying roller in such a state that the operation part is moved from the first position in one direction to dispose it at a second position, and the pressing force of the carrying roller at the second position is changed in such a state that the operation part is moved from the second position further in one direction to dispose it at a third position. As a result, the operability of the medium carrying mechanism carrying the sheet-like recording medium can be improved.

Description

 Specification

 Medium transport mechanism and recording apparatus

 Technical field

 [0001] The present invention relates to a medium transport mechanism and a recording apparatus including the same.

 Background art

 Conventionally, a recording apparatus that prints and records an image on the surface of a sheet-like recording medium, such as an ink jet printer or an impact printer, has been widely used (see, for example, JP-A-5-221053; ). In this type of recording apparatus, a platen on which a recording medium is disposed, a recording head that is disposed at a position facing the platen and records an image on the recording medium, and the recording medium is conveyed to a gap between the platen and the recording head. And a medium transport mechanism. The medium transport mechanism includes a substantially cylindrical transport roller and a pinch roller, and when transporting a recording medium, the transport roller and the pinch roller may be sandwiched between them to rotate the transport roller.

 [0003] This medium transport mechanism includes a switching mechanism that switches between a state in which the recording medium is sandwiched and a state in which the pinching roller is separated from the conveying roller force to release the recording medium. The This mechanism is provided with a switching lever for controlling the movement of the pinch roller. By operating this lever, the two states can be switched.

 [0004] By the way, in recent recording apparatuses, as a recording medium, in addition to paper, various materials such as vinyl chloride and metal are formed into sheets, and various thickness dimensions are available. You are using what you say. For this reason, the medium conveying mechanism is also provided with a pressure adjusting mechanism for adjusting the pressing force of the pinch roller against the conveying roller. The pressure adjusting mechanism is provided with an adjusting lever for changing the pressing force. The pressing force can be adjusted by operating this adjustment lever.

[0005] In the above-described conventional medium transport mechanism and recording apparatus, however, switching of the recording medium sandwiching state and adjustment of the pressing force of the pinch roller against the transport roller are performed separately. Since the operation is performed with a lever, the operation of the media transport mechanism and recording device is troublesome. There is a problem that.

 [0006] In addition, since the structure and the pressure adjusting mechanism are separately configured, the number of parts constituting them increases, which may make it difficult to reduce the size of the recording apparatus.

[0007] The present invention has been made in view of the above circumstances, and provides a medium transport mechanism and a recording apparatus that can improve the operability of the medium transport mechanism and can be easily reduced in size. Objective.

 Disclosure of the invention

 In order to achieve the above object, the present invention provides the following means.

The medium transport mechanism of the present invention transports a sheet-like recording medium in the surface direction, and is a state in which the recording medium is sandwiched together with a rotatable substantially cylindrical transport roller and the transport roller. A substantially cylindrical counter roller that conveys the recording medium by rotating at a position, and a support unit that supports the counter roller so that the counter roller can move in a direction in which the counter roller approaches and separates from the peripheral surface of the transport roller. An operation unit that moves the counter roller relative to the transport roller in accordance with the movement of the operation unit, and the counter roller is arranged around the transport roller in a state where the operation unit is disposed at the first position. In the state where the surface force is arranged at a separated position, and the operation unit is moved in the first position force in one direction and arranged at the second position, the opposing roller is pressed toward the peripheral surface of the transport roller, in front The operation unit is further configured to change the pressing force of the opposing roller at the second position in a state where the second positional force is further moved in one direction and arranged at the third position. To do.

[0010] When the recording medium is attached to or detached from the medium transport mechanism according to the present invention, the operation unit may be moved between the first position and the second position. When the recording medium is attached to the medium conveying mechanism, that is, when the operation unit is disposed at the second position or the third position, the recording medium is held in a state of being sandwiched between the conveying roller and the opposing roller. The Therefore, in this state, the recording medium is conveyed by rotating the conveying roller and the counter roller. Also, if the recording media to be mounted on the media transport mechanism are of different materials and thickness dimensions, the operation unit is placed at the second position and then sandwiched, and then the operation unit is moved to the third position. Roller pressing force, ie That is, the force for pinching the recording medium can be changed by these two rollers.

From the above, it is possible to perform both the operation of switching the approaching / separation of the opposing roller with respect to the conveying roller and the operation of adjusting the pressing force of the opposing roller with respect to the conveying roller by the same operation unit.

 [0012] In addition, the support unit is configured to support the counter roller in a rotatable manner with a base placed at a fixed position with respect to the transport roller, and to move the counter roller toward and away from the transport roller. And a roller support member attached to the base so as to be swingable, and attached to the base so as to be swingable at a position shifted from the swing center axial force of the roller support member. An urging force adjusting member, and an urging member provided between the roller support member and the urging force adjusting member and urging the counter roller toward the conveying roller, and the operation unit includes the roller A rotating part is provided between the supporting member and the biasing force adjusting member so as to be rotatable with respect to the base, and includes a rotating part that rotates in accordance with the movement of the operating part, and the rotating part has a center of rotation. From the axial direction A circumferential surface formed in a substantially circular shape when viewed and a part protruding in the circumferential direction of the circumferential surface, and the operating portion is moved from the second position to the first position. A first cam surface that contacts the roller support member in response to the rotation of the rotating portion and a portion protruding in the circumferential direction of the circumferential surface, and the operating portion is positioned at the second position. A second cam surface that abuts against the biasing force adjusting member in accordance with the rotation of the rotating portion when moved from the third position to the third position, and the first cam surface contacts the roller support member. When contacted, the roller support member is swung in the direction in which the facing roller is separated from the transport roller based on the contact force, and the second cam surface is in contact with the biasing force adjustment member. Further, based on the contact force, the biasing force adjusting member is moved in a direction to change the biasing force of the biasing member. Characterized by being configured to motion.

 [0013] According to the medium transport mechanism of the present invention, the circumferential force of the transport roller can be reliably separated by swinging the roller support member based on the contact of the first cam surface. Togashi.

[0014] Further, by swinging the biasing force adjusting member based on the contact of the second cam surface, the roller support member, the biasing force adjusting member, and the like are kept pressed against the conveying roller. of The distance can be changed. That is, the biasing force of the biasing member disposed between the roller support member and the biasing force adjusting member can be easily reduced or increased. Therefore, it is possible to reliably adjust the pressing force of the facing roller against the conveying roller according to the movement of the operation unit.

 [0015] Further, a plurality of the second cam surface forces projecting from the circumferential surface force are formed side by side in the circumferential direction, and the projecting lengths of the plurality of second cam surfaces are different from each other.

 [0016] According to the medium transport mechanism according to the present invention, the magnitude of the swing of the biasing force adjusting member can be changed according to the protruding length of the second cam surface that contacts the biasing force adjusting member. That is, the urging force of the urging member can be adjusted in multiple stages. Therefore, the pressing force of the opposing roller against the conveying roller can be adjusted in multiple steps.

 [0017] Further, at least one of the components of the transport roller, the counter roller, the support unit, and the operation unit is formed of a resin material. Here, the component parts of the support unit indicate, for example, a base, a roller support member, and an urging force adjusting member. The component of the operation unit indicates, for example, a rotating part.

 [0018] In this configuration, the medium transport mechanism is configured to be lighter than when the components of the transport roller, the opposing roller, the support unit, and the operation unit are formed of other materials such as metal. In addition, the medium transport mechanism can be manufactured inexpensively and easily. Therefore, it is possible to reduce the manufacturing cost of a lightweight apparatus such as a recording apparatus equipped with a medium transport mechanism.

 [0019] Further, the recording apparatus of the present invention includes the transport mechanism and a print recording mechanism that prints and records an image on the surface of the recording medium.

[0020] According to the recording apparatus of the present invention, both the operation of switching the approaching / separating of the opposing roller with respect to the conveying roller and the operation of adjusting the pressing force of the opposing roller with respect to the conveying roller are performed with the same operation unit. Therefore, it is possible to easily print and record an image by the print recording mechanism regardless of the material and thickness of the recording medium. Regardless of the material and thickness of the recording medium, hold the recording medium with an appropriate force and transport it sequentially. Therefore, the positioning accuracy of the recording medium with respect to the print recording mechanism can be improved.

 Brief Description of Drawings

 FIG. 1 is a schematic perspective view showing a recording apparatus according to an embodiment of the present invention.

 2 is a schematic perspective view showing an upper member of a medium transport mechanism in the recording apparatus of FIG.

3 is a schematic perspective view showing an urging force adjusting member of the medium transport mechanism in the recording apparatus of FIG.

 4 is a schematic perspective view showing a rotating part of a medium transport mechanism in the recording apparatus of FIG.

 5 is a schematic perspective view showing a lower member of the medium transport mechanism in the recording apparatus of FIG.

FIG. 6 is a schematic perspective view showing a roller support member of a medium transport mechanism in the recording apparatus of FIG.

 FIG. 7 is a schematic cross-sectional view showing a medium transport mechanism in the recording apparatus of FIG.

 8 is a schematic cross-sectional view showing a state in which the roller support member is swung by the rotating unit and the opposing roller is separated from the transport roller in the medium transport mechanism of FIG.

 9 is a schematic cross-sectional view showing a state in which the urging force of the urging member is changed by swinging the urging force adjusting member by the rotating unit in the medium transport mechanism of FIG.

 10 is a schematic sectional view showing an operation unit in the recording apparatus of FIG.

 BEST MODE FOR CARRYING OUT THE INVENTION

1 to 10 are diagrams showing an embodiment according to the present invention. As shown in FIG. 1, this recording apparatus 1 is a so-called inkjet printer, and a thin sheet-like recording medium (not shown) is passed over a plate-like platen 5 by a plurality of medium transport mechanisms 3. A plurality of ink jet recording heads (printing recording mechanisms) mounted in the carriage 7 while the carriage 7 at the position facing the platen 5 moves along the rail 9 (AB direction) while being transported. Is configured to record an image by ejecting ink toward the surface of the recording medium. The medium transport mechanism 3, the platen 5, and the rail 9 are attached to a metal frame 13, and the mutual positional relationship is fixed by the frame 13. The carriage 7 is movable in the AB direction along the rail 9 by a pulley 15 and a conveyor belt 17 driven by a driving device (not shown). In addition, the ink jet recording head 11 of the present embodiment is configured to eject solvent-based inks having different colors.

 [0024] The conveyance direction of the recording medium by the medium conveyance mechanism 3 is a direction (C direction) orthogonal to the moving direction (AB direction) of the carriage 7, and the platen 5 is arranged in the middle of the conveyance path of the recording medium. Has been. The platen 5 plays a role of supporting the recording medium when the image is recorded by the ink jet recording head 11 and making the above-mentioned ink fit well into the recording medium.

 As shown in FIGS. 2 to 7, the medium transport mechanism 3 includes a transport roller 21 formed in a substantially cylindrical shape, a substantially cylindrical counter roller 23 disposed at a position facing the transport roller 21, and And a support unit 25 that supports the counter roller 23 so as to be movable in the direction of approaching / separating the peripheral surface 21a of the transport roller 21.

 The transport roller 21 is fixed to the frame 13 so as to be rotatable about the axis L1, and is configured to be rotated by a driving means (not shown). The opposing roller 23 is formed in a substantially cylindrical shape like the conveying roller 21, and rotates around an axis L2 parallel to the axis L1 in a state where the recording medium is sandwiched from the thickness direction together with the conveying roller 21. Thus, the recording medium is transported in the C direction, that is, the surface direction of the recording medium.

 [0027] The support unit 25 includes a base unit (base) 27 that is fixed to the frame 13 via the rail 9, and a substantially plate-like roller that is swingably attached to the base unit 27. A supporting member 29 and an urging force adjusting member 31 and a coil spring (urging member) 33 provided between the roller supporting member 29 and the urging force adjusting member 31 are provided.

The base unit 27 is configured to rotatably support a substantially cylindrical rotating part 35 disposed between the roller support member 29 and the biasing force adjusting member 31. The rotating part The lower member 37 and the upper member 39 that sandwich 35 from the arrangement direction of the roller support member 29 and the urging force adjusting member 31 can be separated. The base unit 27 is fixed to the rail 9 by a plurality of mounting portions 37a and 39a formed at the upper ends of the lower member 37 and the upper member 39. By fixing the lower member 37 and the upper member 39 to the rail 9, respectively, the lower member 37 and the upper member 39 are fixed to each other.

 [0029] It should be noted that the lower member 37 and the upper member 39 are in contact with the circumferential surface 35a of the rotating portion 35 so that the rotating portion 35 is rotatable about a rotation center axis L3 parallel to the axis lines LI and L2. Recesses 37b and 39b for supporting are respectively formed.

 [0030] The roller support member 29 is configured such that the counter roller 23 is rotatably attached to one swing end 29a of the roller support member 29. The roller support member 29 swings about a swing center axis L4 parallel to the axes LI and L2. By moving, the opposing roller 23 can be brought close to and away from the conveying roller 21.

 [0031] The biasing force adjusting member 31 is arranged with a gap between the roller support member 29 so that the swing center axis L5 of the bias center axis L5 is also displaced by the swing center axis L4 of the roller support member 29. Here, the swinging center axis L5 of the urging force adjusting member 31 is also parallel to the axes LI and L2, similarly to the swinging center axis L4 of the roller support member 29.

 In the state where the roller support member 29, the urging force adjusting member 31 and the rotating part 35 described above are attached to the base cue 27, the circumferential surface 35a of the rotating part 35 is the roller supporting member 29 and Do not touch the biasing force adjustment member 31!

 The coil spring 33 has one end 33 a fixed to the other swing end 29 b of the roller support member 29 and the other end 33 b fixed to the swing end 31 b of the biasing force adjusting member 31. The roller supporting member 29 is oscillated to urge the opposing roller 23 toward the conveying roller 21. In the present embodiment, in addition to the coil spring 33, an auxiliary coil spring (not shown) for assisting the urging force of the coil spring 33 is provided between the roller support member 29 and the base unit 27. And

 [0034] The rotating portion 35 described above includes a first cam surface 41 and a second cam surface 43 formed so as to project part of the circumferential force of the circumferential surface 35a. The first cam surface 41 and the second force surface 43 are displaced from each other along the rotation center axis L3 of the rotating portion 35 and also from each other in the circumferential direction of the circumferential surface 35a. Formed in position.

[0035] The first cam surface 41 supports the roller facing the rotating portion 35 as shown in FIG. 8 by rotating the rotating portion 35 in one direction (D direction) about the rotation center axis L3. It is adapted to contact the surface 29c of the member 29. More specifically, the first cam surface 41 is a roller support member. It abuts on the surface 29c located between the 29 swing center axis L4 and the other swing end 29b. When the first cam surface 41 contacts the roller support member 29, the roller support member 29 swings in the direction against the biasing force of the coil spring 33 based on the contact force V, As a result, the facing roller 23 is separated from the peripheral surface 21a of the conveying roller 21. As described above, even if the opposing roller 23 is separated from the peripheral surface 21a of the conveying roller 21, the other swinging end 29b of the roller support member 29 does not contact the frame 13! /.

[0036] The roller support member 29, the urging member 33, and the first cam surface 41 of the rotating portion 35 constitute a mechanism 101 for switching the approaching / separating of the opposing roller 23 with respect to the carrying roller 21. Become.

 [0037] The second cam surface 43 is rotated from the state shown in FIG. 7 by rotating the rotating portion 35 in the direction opposite to the D direction (E direction) around the rotation center axis L3 as shown in FIG. In this manner, the surface 31c of the urging force adjusting member 31 facing the rotating portion 35 is brought into contact with the rotating portion 35. More specifically, the second cam surface 43 abuts on the surface 31c located between the swinging center axis L5 of the biasing force adjusting member 31 and the swinging end 31b. In this state, the first cam surface 41 does not contact the surface 3 lc of the biasing force adjusting member 31! /.

 [0038] When the second cam surface 43 abuts against the urging force adjusting member 31, the urging force adjusting member 31 moves in a direction against the urging force of the coil spring 33 based on the abutting force. As a result, the coil spring 33 is extended and its urging force is increased. That is, the force for pressing the opposing roller 23 toward the peripheral surface 21a of the conveying roller 21 is increased.

 [0039] By the second cam surface 43 of the urging force adjusting member 31, the urging member 33, and the rotating portion 35, the pressure adjustment that changes the force pressing the opposing roller 23 toward the peripheral surface 21a of the conveying roller 21. Mechanism 103 will be configured.

 Further, as shown in FIG. 10, the medium transport mechanism 3 is provided with two operation levers (operation units) 51 and 53 that rotate the rotation unit 35. The operation levers 51 and 53 are swingably attached to the frame 13, and their tips protrude from the frame 13. Drive wheels 55 and 57 are fixed to the operation levers 51 and 53 in a body-like manner, and can be rotated around the swing shafts L6 and L7 of the operation levers.

[0041] The drive wheel 55 fixed to one control lever 51 and the frame 13 can be rotated. A belt 63 for power transmission is wound around a plurality of pulleys 59 to 61 and a pulley (not shown) fixed integrally to the rotating portion 35. The drive wheel 57 fixed to the other operation lever 53 sandwiches the belt 63 together with one pulley 59 attached to the frame 13. That is, according to the movement of one of these two operation levers 51 and 53, the rotating part 35 rotates about the rotation center axis L3.

 [0042] The rotating unit 35, the operating levers 51 and 53, the drive wheels 55 and 57, the pulleys 59 to 61, and the belt 63 constitute an operating unit 65. The operation unit 65 is included in both the switching mechanism 101 and the pressure adjusting mechanism 103 described above.

 [0043] In the medium transport mechanism 3 configured as described above, the transport roller 21, the opposing roller 23, the lower member 37 and the upper member 39 constituting the base unit 27, the roller support member 29, the biasing force, The adjusting member 31 and the rotating part 35 are all formed of a resin material such as POM (polyoxymethylene).

 [0044] When recording the image on the recording medium with the recording apparatus 1 configured as described above, first, the operation levers 51 and 53 are moved to a predetermined position (first position). 8, the first cam surface 41 is brought into contact with the roller support member 29, and the opposing roller 23 is disposed at a position separated from the conveying roller 21, as shown in FIG. In this state, the recording medium is disposed between the conveyance port roller 21 and the opposing roller 23.

 [0045] Next, the operation levers 51 and 53 are moved in one direction from the first position to obtain a predetermined position separately.

 By disposing at the (second position), as shown in FIG. 7, the rotating portion 35 rotates in the E direction, and the first cam surface 41 is separated from the roller support member 29. In this state, the opposing roller 23 is pressed toward the peripheral surface 21 a of the conveying roller 21 by the urging force of the coil spring 33. That is, the recording medium is sandwiched between the conveying roller 21 and the opposing roller 23. In this state, the recording medium is sequentially conveyed in the C direction by rotating the conveyance roller 21.

[0046] When the material and thickness of the recording medium are different, the operation levers 51 and 53 are placed in the second position after the operation levers 51 and 53 are arranged at the second position, and then the operation levers 51 and 53 are moved to the second position. By further moving the force in one direction and placing it separately in a predetermined position (third position), the rotating part 35 further rotates in the E direction, and as shown in FIG. 9, the second cam Surface 43 is applied to biasing force adjusting member 31 It will abut. In this state, the force for pressing the opposing roller 23 toward the peripheral surface 21a of the conveying roller 21, that is, the force for pinching the recording medium by the conveying roller 21 and the opposing roller 23 increases.

 [0047] As described above, according to the recording apparatus 1 and the medium transport mechanism 3, by moving the operation levers 51 and 53 between the first position and the second position, An operation of switching between proximity and separation can be performed. Further, by moving the operation levers 51 and 53 between the second position and the third position, an operation for adjusting the pressing force of the facing roller 23 can be performed. That is, the above two types of operations can be performed simply by operating the same operation levers 51 and 53, and as a result, the operability of the medium transport mechanism 3 can be improved.

 In particular, the roller support member 29 and the biasing force adjusting member 31 provided with the coil spring 33 are swingably attached to the base unit 27, and the first cam surface 41 and the second force are attached to the rotating portion 35. By forming the groove surface 43, the opposing roller 23 can be reliably separated from the peripheral surface 21a of the conveying roller 21, and the pressing force of the opposing roller 23 against the conveying roller 21 can be adjusted with certainty. .

 [0049] Further, since the switching mechanism 101 and the pressure adjusting mechanism 103 can be configured by the same operation unit 65, the number of components of each mechanism can be reduced, and the medium transport mechanism 3 and the recording apparatus 1 can be reduced. It is possible to reduce the manufacturing cost while simultaneously reducing the size.

 [0050] Furthermore, since the above two types of operations can be performed simply by operating the same operation levers 51 and 53, an image can be recorded by the inkjet recording head 11 regardless of the material and thickness of the recording medium. It can be performed simply. In addition, regardless of the material and thickness of the recording medium, it is possible to hold the recording medium with an appropriate force and sequentially convey it, thereby improving the positioning accuracy of the recording medium with respect to the ink jet recording head 11. be able to

[0051] Further, the lower roller 37 and the upper member 39, the roller support member 29, the urging force adjusting member 31, and the rotating portion 35 constituting the transport roller 21, the opposing roller 23, and the base unit 27 are formed of a resin material. As a result, the medium transport mechanism 3 can be configured to be lighter than the case of being formed of other materials such as metal, and the medium transport mechanism 3 can be manufactured at low cost and easily. Therefore, the recording device 1 equipped with the medium transport mechanism 3 is made of lightweight Manufacturing cost can be reduced.

 [0052] In the above-described embodiment, only one second cam surface 43 is formed. The force is not limited to this, and a plurality of second cam surfaces 43 are formed over the circumferential direction of the circumferential surface 35a of the rotating portion 35. It does not matter. In the case of this configuration, the projecting heights of the second cam surfaces that are in contact with the urging force adjusting member 31 are formed by forming the projecting heights of the plurality of second cam surfaces different from each other. Accordingly, the magnitude of swinging of the biasing force adjusting member 31 can be changed, that is, the biasing force of the biasing member 33 can be adjusted in multiple stages. Therefore, the pressing force of the opposing roller 23 against the conveying roller 21 can be adjusted in multiple stages. In this configuration, the protruding heights of the plurality of second cam surfaces may be formed so as to continuously change in the circumferential direction.

 [0053] The first cam surface 41 and the second cam surface 43 are forces that are formed at positions shifted from each other along the rotation center axis L3. At least the circumferential surface 35a is not limited to this. It suffices if it is formed at a position shifted in the circumferential direction. In addition, the first cam surface 41 and the second cam surface 43 are formed separately. However, the present invention is not limited to this, and at least the operation levers 51 and 53 are disposed at the first position and the third position. In this state, the cam surface protruding from the circumferential surface 35a may abut on the roller support member 29 and the biasing force adjusting member 31. Therefore, the first cam surface 41 and the second cam surface 43 may be formed as the same cam surface! /.

 Further, the biasing force of the coil spring 33 in the state where the operation levers 51 and 53 are arranged at the third position is assumed to be larger than the biasing force at the second position, but this is not restrictive. By changing the arrangement of the coil spring 33 with respect to the member 29 and the biasing force adjusting member 31, the biasing force of the coil spring 33 in the state where the operation levers 51 and 53 are arranged at the third position is applied to the biasing force at the second position. You may comprise so that it may become smaller than power.

[0055] Further, each operating lever 51, 53 is a force that is attached to the frame 13 so as to be swingable, and is not limited to this. It is sufficient that the operating levers 51, 53 are configured to rotate at least the rotating portion 35. . That is, the operation levers 51 and 53 may be attached so as to swing around the rotation center axis L3 of the rotating unit 35, for example. Further, for example, instead of the operation levers 51 and 53, a dial (operation unit) that is fixed integrally with the rotation unit 35 and is rotatable may be provided. In these cases, control lever 51, 53, dial, Only the rolling part 35 can also constitute an operation unit.

[0056] Further, the opposing roller 23 may be configured to be rotationally driven by a driving means (not shown). In the case of this configuration, the conveyance roller 21 rotates following the rotation of the opposing roller 23.

In the present embodiment, the recording apparatus 1 has been described as applied to an ink jet printer. However, the present invention is not limited to this, and the present invention may be applied to an apparatus that records an image using another method such as an impact printer. .

 As described above, the force described in detail with reference to the drawings for the embodiment of the present invention is not limited to this embodiment, and includes design changes and the like within the scope of the present invention. .

 Industrial applicability

[0059] According to the present invention, the operation unit of the operation unit is moved between the first position and the second position, whereby the operation of switching the proximity roller between the opposing rollers can be performed. In addition, by moving the operation portion between the second position and the third position, an operation for adjusting the pressing force of the opposing roller can be performed. That is, two types of operations can be performed simply by operating the same operation unit, and as a result, the operability of the medium transport mechanism can be improved.

 [0060] In addition, since a mechanism for performing two types of operations with the same operation unit can be configured, the number of component parts can be reduced, the medium transport mechanism and the recording apparatus can be downsized, and the manufacturing cost can be reduced. At the same time.

Claims

The scope of the claims  [1] A medium transport mechanism for transporting a sheet-like recording medium in the surface direction,  A rotatable substantially cylindrical transport roller;  A substantially cylindrical counter roller that conveys the recording medium by rotating in a state of sandwiching the recording medium together with the conveying roller;  A support unit that supports the counter roller so that it can move in the direction of approaching and separating from the peripheral surface of the transport roller;  An operation unit that moves the counter roller with respect to the transport roller according to the movement of the operation unit,  In the state where the operation unit is arranged at the first position, the counter roller is arranged at a position away from the circumferential force of the conveying roller,  In a state where the operation unit is moved in one direction of the first positional force and arranged in the second position, the opposing roller is pressed toward the peripheral surface of the transport roller,  In the state in which the operation unit is further moved in one direction to the second position force and is arranged at the third position, the pressing force of the facing roller at the second position is changed. A medium transport mechanism. [2] The support unit rotatably supports the base disposed at a position fixed with respect to the transport roller and the counter roller, and moves the counter roller toward and away from the transport roller. The roller support member that is swingably attached to the base and the attachment that is swingably attached to the base at a position shifted from the swing center axial force of the roller support member. An urging force adjusting member; and an urging member provided between the roller support member and the urging force adjusting member and urging the opposing roller toward the conveying roller,  The operation unit is provided between the roller support member and the urging force adjustment member so as to be rotatable with respect to the base, and includes a rotation unit that rotates according to the movement of the operation unit, The rotating part is formed so as to project from a circumferential surface formed in a substantially circular shape when viewed in the axial force of the rotation center, and a part of the circumferential surface in the circumferential direction. Before A first cam surface that comes into contact with the roller support member according to the rotation of the rotating portion when moved to the first position, and a partial force protruding in a circumferential direction of the circumferential surface, A second cam surface that comes into contact with the biasing force adjusting member according to the rotation of the rotating part when the operating part is moved from the second position to the third position;  When the first cam surface comes into contact with the roller support member, the roller support member is swung in a direction in which the facing roller is separated from the transport roller based on the contact force,  When the second cam surface abuts against the urging force adjusting member, the urging force adjusting member is swung in a direction in which the urging force of the urging member is changed based on the abutting force. The medium transport mechanism according to claim 1, wherein: [3] The circumferential surface force projecting from the second cam surface force.  The medium conveying mechanism according to claim 2, wherein the protruding lengths of the plurality of second cam surfaces are different from each other.  [4] Any one of claims 1 to 3, wherein at least one of the components of the transport roller, the opposing roller, the support unit, and the operation unit is formed of a resin material. The medium transport mechanism according to claim 1.  [5] A recording apparatus comprising: the medium conveying mechanism according to any one of claims 1 to 4; and a print recording mechanism that prints and records an image on a surface of the recording medium.