JP2020121815A - Media transport mechanism and printing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printing apparatus capable of easily performing an adjustment work for adjusting a holding force of a driving roller and a driven roller which hold and convey a medium. A conveying unit 20 is connected to a driving roller 21 that conveys a roll paper 1, a driven roller 22 that presses the roll paper 1 against the driving roller 21, and a driven roller support member 26 that supports the driven roller 22. By selecting a coil spring 27 that applies a pressing force to the driven roller 22 and a state of one length from a plurality of lengths of the coil spring 27, a push corresponding to the state of one selected length is selected. A driven roller 22 and a driven roller 22 are provided with a pressing force setting unit 25 for setting a pressure and a pressing force adjusting unit 28 for adjusting a set pressing force by adjusting a selected length of a coil spring 27. The setting operation position in the pressing force setting unit 25 and the adjusting operation position in the pressing force adjusting unit 28 are arranged in the order of the driven roller 22, the setting operation position, and the adjusting operation position in a predetermined direction. [Selection diagram] Fig. 3

Description

The present invention relates to a media transport mechanism and a printing apparatus including the media transport mechanism.

2. Description of the Related Art Conventionally, for example, as described in Patent Document 1, a printing apparatus is known that includes a conveyance device that nips and conveys a medium with a pair of rollers.
The transport device described in Patent Document 1 includes a drive roller that can transport a medium in the transport direction, a driven roller that presses the medium against the drive roller, and a changing unit that changes the pressing force of the driven roller. Further, the changing unit is configured so that the pressing force of the driven roller can be adjusted. Accordingly, even if the pressing force of the driven roller that presses the medium varies in the width direction of the medium, the variation can be suppressed within a predetermined range by adjustment.

JP, 2016-175763, A

However, in the transport device described in Patent Document 1, since the adjustment portion for adjusting the pressing force of the driven roller is located inside the printing device at a position that is difficult to access, there is a problem that it is difficult to perform the adjustment work. there were.

The media transport mechanism of the present application is connected to a drive roller that transports a medium, a driven roller that presses the medium against the drive roller, and a support portion that supports the driven roller, and an elasticity that applies a pressing force to the driven roller. A member and a pressing force setting unit that sets a pressing force corresponding to the selected one state by selecting one state from a plurality of states of the elastic member, and the selected elastic member. A pressing force adjusting unit for adjusting the set pressing force by adjusting the one state, and performing a setting operation for selecting the one state in the driven roller and the pressing force setting unit. A setting operation position and an adjustment operation position for performing an adjustment operation for adjusting the one state in the pressing force adjusting unit are arranged in a predetermined direction in the order of the driven roller, the setting operation position, and the adjustment operation position. It is characterized by

The medium transport mechanism of the present application is a coil that is connected to a drive roller that transports a medium, a driven roller that presses the medium against the drive roller, and a support portion that supports the driven roller, and that applies a pressing force to the driven roller. A spring and a pusher having a cam for setting a pushing force corresponding to the selected one length state by selecting one length state from a plurality of length states of the coil spring. A pressure setting unit and a pressing force adjusting unit that adjusts the set pressing force by adjusting the one length of the coil spring, the driven roller, the cam, and the pressing force. The adjustment operation position for performing the adjustment operation for adjusting the one length in the adjustment unit is arranged in the predetermined direction in the order of the driven roller, the cam, and the adjustment operation position.

In the media transport mechanism, the position of one end of the coil spring is selectively set by the rotation of the cam, and the other end of the coil spring is set by the adjustment of the pressing force adjusting unit. It is preferable that the connection position where the support is connected is adjusted.

In the above-described media transport mechanism, the support portion is rotatable about a first shaft that supports the support portion as a rotation axis, and the pressing force adjusting portion is a second shaft supported by the support portion. A rotary member that is rotatable about the second shaft as a rotary shaft, and the other end of the coil spring is connected to the end of the rotary member. Preferably has a fitting portion fitted and fixed to the support portion at a plurality of rotation positions.

In the above-described media transport mechanism, the support section is rotatable about a first axis that supports the support section as a rotation axis, and the pressing force adjusting section is parallel to a plane on which the support section rotates. It is preferable to have a plurality of locking portions for locking the other end of the coil spring in the plane.

A printing apparatus of the present application is characterized by including the above-described media transport mechanism and a printing unit that prints on a medium.

1 is a schematic side view of a printer as a printing apparatus according to a first embodiment. 1 is a block diagram of a printer as a printing apparatus according to a first embodiment. FIG. It is a side view showing the composition of the transportation part as a media transportation mechanism. FIG. 3 is a plan view of a transport unit as a media transport mechanism and its peripheral portion. FIG. 6 is a side view showing a configuration of a carrying section as a media carrying mechanism included in a printer as a printing apparatus according to a second embodiment. FIG. 11 is a side view showing a configuration of a transport unit as a media transport mechanism according to Modification Example 1. FIG. 13 is a side view showing a configuration of a transport unit as a media transport mechanism according to Modification 2.

Embodiments embodying the invention of the present application will be described below with reference to the drawings. The following is an embodiment of the invention of the present application and does not limit the invention of the present application. In addition, in each of the following drawings, in order to make the description easy to understand, the scale may be different from the actual scale. In the coordinates attached to the drawings, the Z-axis direction is the vertical direction, the +Z direction is the upward direction, the Y-axis direction is the front-back direction or the front/back direction, the +Y direction is the front or front direction, and the X-axis direction is the horizontal direction or The lateral direction, the +X direction is the left direction, and the XY plane is the horizontal plane.
In addition, the term “parallel” in the present application is not limited to being parallel in a strict sense, but includes a state of being arranged in parallel, that is, a state including an error due to a variation in manufacturing accuracy.

(Embodiment 1)
FIG. 1 is a schematic side view of a printer 100 as a printing apparatus according to the first embodiment. FIG. 2 is a block diagram of the printer 100.
The printer 100 is an ink jet printer that prints an image on the roll paper 1 supplied in a rolled state as a long medium.
The printer 100 includes a printing unit 10, a transport unit 20 serving as a media transport mechanism, an unwinding unit 30, a winding unit 40, a transport support unit 60, a control unit 70, and the like.
As the roll paper 1, for example, high-quality paper, cast paper, art paper, coated paper, synthetic paper, or a film made of PET (Polyethylene terephthalate), PP (polypropylene), or the like can be used.

The printing unit 10 includes a print head 11, a carriage 12, a guide shaft 13, and the like. The print head 11 is an inkjet head including a plurality of nozzles that eject ink. The guide shaft 13 extends in the width direction of the roll paper 1 that intersects the transport direction A in which the roll paper 1 is transported. The transport direction A is a direction in which the roll paper 1 travels on a transport path from the unwinding unit 30 to the winding unit 40 via a printing area where the printing unit 10 prints. In the following description, the width direction of the roll paper 1 is the X-axis direction, and the direction in which the roll paper 1 is conveyed in the printing area where the printing unit 10 prints is the Y-axis direction.
The carriage 12 has the print head 11 mounted thereon, and is reciprocally moved along the guide shaft 13 by a carriage motor 14 (see FIG. 2) which is driven and controlled by the controller 70.
The control unit 70 alternately repeats an ejection operation of ejecting ink droplets from the print head 11 while moving the carriage 12 in the X-axis direction and a transport operation of transporting the roll paper 1 in the transport direction A by the transport unit 20. Thus, a desired image is printed on the roll paper 1.

Although the printing unit 10 is configured by the serial head that reciprocates in the X-axis direction as described above, it extends across the width of the roll paper 1 in the direction that intersects the nozzles that eject ink with the transport direction A. Alternatively, the line heads may be arranged side by side. Further, the printing apparatus may have a printing unit other than the so-called inkjet type print head as described above.

The transport unit 20 is a transport mechanism that applies a transport force to the roll paper 1 and transports the roll paper 1, and is provided in the transport direction A on the upstream side of a printing area in which printing is performed by the printing unit 10. The transport unit 20 includes a drive roller 21, a driven roller 22, a transport motor 23, a support 24, a pressing force setting unit 25, and a rotary encoder (not shown).

The drive roller 21 drives the roll paper 1 while sandwiching the roll paper 1 between the driven roller 21 and the driven roller 22, thereby imparting a transport force to the roll paper 1 and transporting the roll paper 1. Further, the transport section 20 drives the transport motor 23, that is, the drive roller 21 in the opposite direction to move the roll paper 1 in the direction opposite to the transport direction A in order to feed back the roll paper 1. be able to.
The pressing force setting unit 25 sets the pressing force of the driven roller 22 required when the driven roller 22 and the drive roller 21 sandwich the roll paper 1.
The features of the transport unit 20 in the present application will be described later.

The unwinding unit 30 is a storage unit that stores the roll paper 1 before printing, is located on the upstream side of the printing unit 10 and the transporting unit 20 in the transport direction A, and includes the unwinding reel 31 and the like. There is.
The unwinding reel 31 is rotated by an unwinding motor 32 (see FIG. 2) which is driven and controlled by the control unit 70, so that the roll paper 1 is arranged on the downstream side of the unwinding unit 30 and the printing unit 10. Unwind towards.
In addition, the unwinding unit 30 can wind up the back-fed roll paper 1 by driving the unwinding reel 31 in the opposite direction.

The winding unit 40 is a storage unit that winds the roll paper 1 transported from the printing unit 10 and stores the roll paper 1 in a rolled state, and is located downstream of the printing unit 10 in the transport direction A of the roll paper 1. It is provided with a take-up reel 41 and the like.
The take-up reel 41 has a rotary shaft that is rotated by a take-up motor 42 (see FIG. 2) that is driven and controlled by the control unit 70, and is sent through the printing area of the printing unit 10 with the rotary shaft as the axis. Roll up roll paper 1. A rotary encoder (not shown) is provided on the rotary shaft.
Further, the winding section 40 can unwind the back-fed roll paper 1 by driving the winding reel 41 in the opposite direction.

The transport support unit 60 transports the platen 61 that sucks and supports the roll paper 1 in the printing region of the printing unit 10 and the roll paper 1 from the unwinding unit 30 to the winding unit 40 via the printing unit 10. Alternatively, it is composed of the medium support portion 62 and the like which constitutes a conveyance path for back feeding on the reverse path.
The roll paper 1 is supplied from the unwinding unit 30 and is stored in the winding unit 40 via the printing unit 10 by the transport support unit 60 in accordance with the printing operation.

As shown in FIG. 2, the control unit 70 includes an input/output unit 71, a CPU 72, a memory 73, a head drive unit 75, a motor drive unit 76, a system bus 77, and the like, and performs centralized control of the entire printer 100.
The input/output unit 71 transmits/receives data between an external device PC such as a personal computer and the printer 100, for example.
The CPU 72 is an arithmetic processing unit for controlling the entire printer 100, and is connected to the input/output unit 71, the memory 73, the head drive unit 75, and the motor drive unit 76 via the system bus 77.
The memory 73 is an area for storing a program for operating the CPU 72 and storing necessary information, and is composed of a storage element such as a RAM, a ROM, or a flash memory.
The CPU 72 controls the head drive unit 75 and the motor drive unit 76 according to a program stored in the memory 73 and a print instruction received from an external device.

The control unit 70 can recognize the rotational speed of the drive roller 21, the movement amount of the roll paper 1 in the transport unit 20, the transport speed, and the like from the reading value of the rotary encoder provided in the transport unit 20.
Further, the control unit 70 can recognize the amount of movement of the roll paper 1 in the winding unit 40, the winding speed, and the like from the reading value of the rotary encoder provided on the winding reel 41.

FIG. 3 is a side view showing the configuration of the transport unit 20, and FIG. 4 is a plan view of the transport unit 20 and its peripheral portion. Note that, in FIGS. 3 and 4, a part of the configuration of the transport unit 20 is omitted.
The transport unit 20 includes a drive roller 21, a driven roller 22, a driven roller support member 26 as a support unit, a coil spring 27, a pressing force setting unit 25, and a pressing force adjusting unit 28.

As shown in FIG. 4, the drive roller 21 is one roller having a length substantially the same as the width of the roll paper 1 having the maximum width targeted by the printer 100. The drive roller 21 has a rotating shaft 211 extending in the X-axis direction, which is supported by a support base 24 (see FIG. 1), and is controlled by a control unit 70 (see FIG. 1) to convey motor 23 (see FIG. 1). Drive).

The plurality of driven rollers 22 are arranged side by side in the X-axis direction so as to sandwich the roll paper 1 with the drive roller 21. The driven roller 22 has a rotating shaft 221 that is supported by the driven roller support member 26 and extends in the X-axis direction. The driven roller 22 presses the roll paper 1 against the drive roller 21 and rotates as the roll paper 1 moves. If the roll paper 1 can be conveyed, the number of driven rollers 22 may be one.

As shown in FIG. 4, the plurality of driven roller support members 26 are supported by a support member rotation shaft 261 as a first shaft that is erected on a support frame 50 provided outside the transport path of the roll paper 1. In the aspect, one driven roller support member 26 provided side by side in the X-axis direction rotatably supports the two driven rollers 22. The driven roller support member 26 is rotatable in the YZ plane about a support member rotation shaft 261 extending in the X axis direction.
The transport support section 60, the support base 24, and the support frame 50 are fixedly supported as a device. It should be noted that the number of the driven roller supporting members 26 may be one as long as the driven roller 22 can be supported.

The driven roller support member 26 supports the rotating shaft 221 of the driven roller 22 at the end portion in the +Y direction. Further, a pressing force adjusting portion 28 is provided at the −Y direction end of each driven roller support member 26 with the support member rotation shaft 261 sandwiched between the support roller and the rotation shaft 221.
The rotary shaft 221 of the driven roller 22 supported by the driven roller support member 26 is provided independently of each driven roller support member 26. In the example shown in FIG. 4, the two driven rollers 22 are supported by one driven roller support member 26, but one driven roller 22 is supported by one driven roller support member 26. May be.

The coil spring 27 is an elastic member that generates a pressing force applied to the driven roller 22 when the driven roller 22 presses the drive roller 21 via the roll paper 1, and is provided for each driven roller support member 26. ing. One end 27 a of the coil spring 27 is connected to the pressing force setting unit 25, and the other end 27 b is connected to the driven roller support member 26 via the pressing force adjusting unit 28.
As the coil spring 27, it is preferable to use a tension spring, and further, it is preferable to use a tension coil spring that has a force in a direction in which the windings of the coils are in close contact with each other even under no load.

The pressing force setting unit 25 is a mechanism that selectively sets the pressing force of the driven roller 22 when the driven roller 22 and the driving roller 21 nip the roll paper 1, and is provided for each driven roller support member 26. Has been. The pressing force setting unit 25 sets the pressing force by selecting one of the states of the coil spring 27. Specifically, the pressing force setting unit 25 has a cam structure for setting the pressing force by selectively setting one length state from the plurality of length states of the coil spring 27. is there. The cam structure has a cam 251, a cam bar 252, and the like.

The cam 251 rotates in the YZ plane by a cam rotation shaft 253 provided in parallel with the drive roller 21 in the width direction of the roll paper 1, and the distance from the cam rotation shaft 253 continuously changes. The cam outer peripheral surface 251a is configured to contact the lower surface of the cam bar 252. The cam rotation shaft 253 is located in the +Z direction and the −Y direction with respect to the support member rotation shaft 261, and is rotatably supported by the support frame 50. The cams 251 provided in the individual pressing force setting portions 25 are attached to the cam rotation shaft 253 so as to rotate in the same phase according to the rotation of the cam rotation shaft 253. The rotation angle of the cam rotation shaft 253 is controlled by a cam motor (not shown) controlled by the control unit 70.

The cam bar 252 is a structural member that rotates in the YZ plane about a cam bar rotation shaft 254 provided at the end of the cam bar 252 in the +Y direction as an axis, and contacts the cam outer peripheral surface 251 a above the cam 251. It has a surface 252a. The contact surface 252a is synonymous with the lower surface of the cam bar 252. The cam bar rotation shaft 254 is rotatably supported by the support frame 50 at a position in the +Z direction with respect to the support member rotation shaft 261. One end 27 a of the coil spring 27 is connected to the −Y direction end of the cam bar 252. The cam bar 252 receives a pressing force from the cam 251 between the cam bar rotating shaft 254 and the connecting portion of the coil spring 27, and rotates about the cam bar rotating shaft 254 as an axis, whereby the end portion of the cam bar 252 in the −Y direction. The coil spring 27 connected to is expanded and contracted.

For example, when the driven roller 22 and the drive roller 21 nip the roll paper 1, the cam bar 252 receives the pressing force of the cam 251 and extends the coil spring 27, so that the cam bar 252 is supported by the tip end portion of the driven roller support member 26. The driven roller 22 generates a pressing force for pressing the roll paper 1 against the drive roller 21 located below the driven roller 22. In this way, since the urging force when the coil spring 27 extends becomes the pressing force of the driven roller 22, the pressing force of the driven roller 22 becomes stronger as the extension length of the coil spring 27 becomes longer. That is, the rotation of the cam 251 selectively sets the position of the one end 27a of the coil spring 27, and the pressing force corresponding to the rotation position of the cam 251 is set.
The control unit 70 controls the pressing force to have a preset value according to the thickness and material of the roll paper 1 and according to the operation mode of the printer 100, such as the transport and release of the roll paper 1. Is selected by controlling the rotation angle of the cam rotation shaft 253. That is, in the present embodiment, the position of the cam 251 and, more specifically, the position of the cam rotation shaft 253, the pressing force setting unit 25 selects one state of the coil spring 27 and sets the pressing force. Corresponds to the setting operation position for performing.

The pressing force adjusting unit 28 is a mechanism that adjusts the set pressing force by adjusting one selected length of the coil spring 27, and is provided for each driven roller support member 26. The adjustment of the pressing force is performed by adjusting the variation in the pressing force between the individual driven rollers 22 within a predetermined allowable range, or by adjusting the pressing force applied by one driven roller 22 to be the predetermined pressing force. If you do.

The pressing force adjusting unit 28 has a pressing force adjusting plate 281 as a rotating member and an adjusting plate rotating shaft 282 as a second shaft.
The adjusting plate rotation shaft 282 is provided so as to extend in the X-axis direction in the region of the end portion of the driven roller support member 26 in the −Y direction, and is supported by the driven roller support member 26.
The pressing force adjusting plate 281 is provided rotatably in the YZ plane at a position overlapping the −X direction end region of the driven roller support member 26 in the −X direction with the adjusting plate rotation shaft 282 as the rotation axis. The other end 27b of the coil spring 27 is connected to the end of the pressing force adjusting plate 281 in the -Y direction.

The pressing force adjusting plate 281 has a fitting portion 283 which is fitted and fixed to the driven roller support member 26 at a plurality of rotation positions. The fitting portion 283 is composed of a plurality of fitting holes 283a provided on the +Y side peripheral portion of the pressing force adjusting plate 281. The plurality of fitting holes 283a are provided at a constant pitch with respect to each other at positions at substantially equal distances from the adjusting plate rotating shaft 282. One or a plurality of protrusions (not shown) that fit into the fitting holes 283a are provided in a region of the driven roller support member 26 that faces the fitting portion 283. When a plurality of protrusions are provided, the distance between the plurality of protrusions corresponds to the pitch of the fitting holes 283a. The protrusion fitted into the fitting hole 283a is made of a resin that is elastically deformed. When the pressing force adjusting plate 281 is rotated with respect to the driven roller supporting member 26, the pressing force adjusting plate 281 has a plurality of rotations in which the protrusions provided on the driven roller supporting member 26 fit into the fitting holes 283a. It is fitted and fixed in the moving position. Since the protrusion provided on the driven roller support member 26 elastically deforms, the fitting position can be changed from the specific fitting position to another fitting position at the pitch of the plurality of fitting holes 283a. The minimum angle of rotation of the pressing force adjusting plate 281 determined by the pitch of the plurality of fitting holes 283 a is the pressing force adjusting resolution of the pressing force adjusting unit 28.
The configuration of the fitting portion 283 is not limited to the above-described fitting with the hole and the projection. For example, the protrusions protruding from the driven roller support member 26 and the protrusions protruding from the pressing force adjusting plate 281 which are provided so as to face each other may be fitted together.

In such a configuration of the pressing force adjusting unit 28, for example, the pressing force adjusting plate 281 is moved from the rotating position of the pressing force adjusting plate 281 shown by the solid line in FIG. 3 to the rotating position of the pressing force adjusting plate 281 shown by the broken line. When rotated, the other end 27b of the coil spring 27 connected to the end of the pressing force adjusting plate 281 in the −Y direction is pulled substantially downward, and the end of the cam bar 252 in the −Y direction is pulled. The coil spring 27 extends to one end portion 27a of the coil spring 27 connected to the. As a result, the pressing force with which the driven roller 22 presses the roll paper 1 against the drive roller 21 increases. I mean. By adjusting the pressing force adjusting unit 28, the connecting position where the other end 27b of the coil spring 27 is connected to the driven roller supporting member 26 is adjusted, and the pressing force by which the driven roller 22 presses the roll paper 1 against the drive roller 21 is adjusted. It is adjusted so as to have a predetermined pressing force F.

In FIG. 3, for the sake of clarity, the pitch of the plurality of fitting holes 283a fitted at a plurality of turning positions, that is, the adjustment resolution is roughly drawn, and the turning angle from the solid line to the broken line is shown largely. However, it is preferable that the adjustment resolution of the fitting portion 283 is configured to be finer so that the pressing force set by the pressing force setting unit 25 can be finely adjusted. For example, by configuring the pressing force adjustment plate 281 to be longer so that the fitting portion 283 is provided at a position further away from the adjustment plate rotation shaft 282 in the +Y direction, the rotation angle corresponding to the pitch of the plurality of fitting holes 283a. The adjustment resolution of the fitting portion 283 determined by can be made finer.

In the pressing force adjusting unit 28, the adjusting operation position for adjusting the selected length of the coil spring 27 and adjusting the pressing force is the position for adjusting the rotation angle of the pressing force adjusting plate 281. As shown in FIG. 4, since the plurality of driven roller support members 26 are arranged in the X-axis direction, the pressing force adjusting plate 281 is accessed in the Y direction, which is easier to access, to perform the adjusting operation. .. That is, in the present embodiment, the adjustment operation position is the end portion of the pressing force adjustment plate 281 in the −Y direction.
That is, the driven roller 22, the setting operation position for performing the setting operation for selecting the one state in the pressing force setting unit 25, and the adjusting operation position for performing the adjustment operation for adjusting the one state in the pressing force adjusting unit 28. However, in the −Y direction as the predetermined direction, the driven roller 22, the setting operation position, and the adjustment operation position are arranged in this order.

As described above, the media transport mechanism according to this embodiment has the advantages described below.
The driven roller 22, the setting operation position for performing the setting operation for selecting the one state in the pressing force setting unit 25, and the adjustment operation position for performing the adjustment operation for adjusting the one state in the pressing force adjusting unit 28 are The driven roller 22, the setting operation position, and the adjusting operation position are arranged in this order in a predetermined direction. Since the adjustment operation position is not arranged between the driven roller 22 and the setting operation position, the printer 100 is configured to be easily accessible to the adjustment operation position. As a result, the adjustment work for adjusting the pressing force of the driven roller 22 can be facilitated.

More specifically, when the driven roller 22, the cam 251 of the pressing force setting unit 25, and the adjusting operation position for performing the adjusting operation for adjusting the one state in the pressing force adjusting unit 28 are in a predetermined direction, The driven roller 22, the cam 251, and the adjustment operation position are arranged in this order. Since the adjustment operation position is not arranged between the driven roller 22 and the cam 251, the printer 100 is configured to be easily accessible to the adjustment operation position. Further, since the plurality of driven roller support members 26 are arranged in the X-axis direction, the pressing force adjusting plate 281 can be accessed from the -Y direction, which is easier to access, to perform the adjusting operation.

The position of one end 27a of the coil spring 27 is selectively set by the rotation of the cam 251 of the pressing force setting unit 25, and the other end of the coil spring 27 is adjusted by the adjustment of the pressing force adjusting unit 28. The connection position where the part 27b is connected is adjusted. That is, the position where the pressing force setting unit 25 that sets the pressing force applied to the driven roller 22 acts and the position where the pressing force adjusting unit 28 that adjusts the pressing force acts are divided into both ends of the coil spring 27. Since it can be configured, the transport unit 20 can be configured with a simpler structure.

Further, the other end 27b of the coil spring 27 is provided at the end of the pressing force adjusting plate 281 which is rotatable about the adjusting plate rotating shaft 282 supported by the driven roller supporting member 26 which supports the driven roller 22. The pressing force adjusting plate 281 has a fitting portion 283 that is fitted and fixed to the driven roller support member 26 at a plurality of rotation positions. Therefore, by rotating the pressing force adjusting plate 281, the connecting position connected to the driven roller support member 26 is adjusted while the other end 27b of the coil spring 27 is connected to the end of the pressing force adjusting plate 281. can do. Further, the adjustment of the connecting position can be performed by selecting from a plurality of rotational positions where the pressing force adjusting plate 281 is fitted and fixed to the driven roller supporting member 26.

(Embodiment 2)
FIG. 5 is a side view showing a configuration of a transport unit 320 as a media transport mechanism included in the printer 100A as the printing apparatus according to the second embodiment.
The printer 100</b>A is the same as the printer 100 except that the transport unit 320 is provided instead of the transport unit 20, and thus the illustration thereof is omitted. Further, in the following description, the same numbers are used for the same components as those of the first embodiment, and duplicate explanations are omitted.

The transport unit 320 includes a drive roller 21, a driven roller 22, a driven roller support member 326, a coil spring 27, a pressing force setting unit 325, and a pressing force adjusting unit 328.
A plurality of driven roller support members 326 are provided in the X-axis direction such that the driven roller support members 326 are supported by a support member rotation shaft 261 provided on a support frame 50 provided outside the conveyance path of the roll paper 1, and one driven roller is provided. A support member 326 rotatably supports the two driven rollers 22. The driven roller support member 326 is rotatable in the YZ plane about the support member rotation shaft 261 extending in the X axis direction.

The driven roller support member 326 supports the rotation shaft 221 of the driven roller 22 at the end portion in the +Y direction. Further, one end portion 27c of the coil spring 27 is connected to the −Y direction end portion of each driven roller support member 326 that sandwiches the support member rotation shaft 261 with the rotation shaft 221.
The coil spring 27 is provided for each individual driven roller support member 326. One end 27c of the coil spring 27 is connected to the driven roller support member 326, and the other end 27d is connected to the pressing force setting unit 325.

The pressing force setting unit 325 is a mechanism that selectively sets the pressing force of the driven roller 22 when the driven roller 22 holds the roll paper 1 between the driven roller 22 and the driving roller 21, and each driven roller support member 326 is individually set. It is provided in. The pressing force setting unit 325 sets the pressing force by selecting one of the plurality of states of the coil spring 27. Specifically, the pressing force setting unit 325 has a cam structure for setting the pressing force by selectively setting one length state from the plurality of length states of the coil spring 27. is there. The cam structure has a cam 251, a cam bar 3252, and the like.

The cam 251 rotates in the YZ plane by a cam rotation shaft 253 provided in parallel with the drive roller 21 in the width direction of the roll paper 1, and the distance from the cam rotation shaft 253 continuously changes. The cam outer peripheral surface 251a is configured to contact the lower surface of the cam bar 3252. The cams 251 provided in the individual pressing force setting portions 325 are attached to the cam rotation shaft 253 so as to rotate in the same phase as the cam rotation shaft 253 rotates.

The cam bar 3252 is a structural member that is provided at the end of the cam bar 3252 in the −Y direction and that rotates in the YZ plane about the cam bar rotation shaft 3281 supported by the pressing force adjustment unit 328 as an axis. Has a contact surface 3252a that contacts the cam outer peripheral surface 251a. The contact surface 3252a is synonymous with the lower surface of the cam bar 3252. The other end 27d of the coil spring 27 is connected to the end of the cam bar 3252 in the +Y direction. The cam bar 3252 pushes the cam 251 from the cam 251 between the cam bar rotating shaft 3281 and the connection of the coil spring 27. The coil spring 27 connected to the end portion of the cam bar 3252 in the +Y direction is expanded and contracted by receiving pressure and rotating about the cam bar rotation shaft 3281.

For example, when the driven roller 22 and the drive roller 21 sandwich the roll paper 1, the cam bar 3252 receives the pressing force of the cam 251 and extends the coil spring 27, so that the driven roller support member 326 is supported by the tip end portion of the driven roller support member 326. The driven roller 22 generates a pressing force for pressing the roll paper 1 against the drive roller 21 located below the driven roller 22.
Also in the present embodiment, for the position of the cam 251, more specifically, the position of the cam rotation shaft 253, the pressing force setting unit 325 selects one state of the coil spring 27 and sets the pressing force. It corresponds to the setting operation position to be performed.

The pressing force adjusting portion 328 is a mechanism that adjusts the set pressing force by adjusting one state of the coil spring 27, that is, one selected length, and for each driven roller support member 326. It is provided in.
The pressing force adjusting portion 328 has a shaft support portion 3228 that supports the cam bar rotation shaft 3281, and a screw mechanism 3283 that moves the shaft support portion 3282 up and down in the Z-axis direction.
The screw mechanism 3283 has a male screw formed so as to project above the shaft support portion 3228, and a female screw that is rotatable by fitting this male screw. The female screw included in the screw mechanism 3283 is fixedly supported together with the transport support portion 60, the support base 24, and the support frame 50 in a state in which the position thereof is rotatable, and the pressing force adjusting portion 328 is formed by rotating the female screw. The shaft support portion 3282 fitted to the female screw is configured to move in the Z-axis direction.

For example, in the state shown in FIG. 5, when the position of the shaft support portion 3382 is moved in the −Z direction by the screw mechanism 3283 of the pressing force adjustment portion 328, the coil spring 27 connected to the end portion of the cam bar 3252 in the +Y direction is moved. Extend. As a result, the predetermined pressing force F by which the driven roller 22 presses the roll paper 1 against the drive roller 21 increases.

In the pressing force adjusting unit 328, the adjusting operation position for adjusting the selected length of the coil spring 27 and adjusting the pressing force is the position for rotating the female screw of the screw mechanism 3283. That is, in the present embodiment, the adjustment operation position is the end portion of the transport unit 320 in the −Y direction.
That is, the driven roller 22, the setting operation position for performing the setting operation for selecting the one state in the pressing force setting unit 25, and the adjusting operation position for performing the adjustment operation for adjusting the one state in the pressing force adjusting unit 28. However, in the −Y direction as the predetermined direction, the driven roller 22, the setting operation position, and the adjustment operation position are arranged in this order. Since the adjustment operation position is not arranged between the driven roller 22 and the setting operation position, the printer 100A including the transport unit 320 is configured to be easily accessible to the adjustment operation position. As a result, the adjustment work for adjusting the pressing force of the driven roller 22 can be facilitated. Further, in the case of the configuration of the present embodiment, since the driven roller 22, the setting operation position, and the adjustment operation position are arranged in this order in the +Z direction, the adjustment operation position can be easily accessed from the +Z direction.

The invention of the present application is not limited to the above-described embodiments, and various modifications and improvements can be added to the above-described embodiments. A modified example will be described below.

(Modification 1)
FIG. 6 is a side view showing the configuration of the transport unit 420 as a media transport mechanism according to the first modification.
The transport unit 420 will be described with reference to FIG. The same components as those in the first embodiment are designated by the same reference numerals, and the duplicate description will be omitted.

The transport unit 420 includes a drive roller 21, a driven roller 22, a driven roller support member 426, a coil spring 27, a pressing force setting unit 25, and a pressing force adjusting unit 428.
The conveying unit 420 includes a pressing force adjusting unit 428 instead of the pressing force adjusting unit 28 at the −Y direction end of the driven roller support member 426. Except for this point, the transport unit 420 is the same as the transport unit 20.

The pressing force adjusting portion 428 is configured by a plurality of locking holes 4281 serving as a plurality of locking locations for locking the other end 27b of the coil spring 27. The plurality of locking holes 4281 are holes for locking the other end 27b of the coil spring 27 formed in a hook shape. In addition, the plurality of locking holes 4281 are provided at predetermined intervals along the Z-axis direction at the −Y direction end of the driven roller support member 426 that sandwiches the support member rotation shaft 261 with the rotation shaft 221. It is provided.
In this modification, the operation of changing the locking position for locking the other end portion 27b of the coil spring 27 is performed by adjusting one state of the coil spring 27, that is, one selected length, and pressing force. It corresponds to the adjusting operation for adjusting. Further, the interval between the plurality of locking holes 4281 becomes the adjustment resolution of the pressing force in the pressing force adjusting unit 428. That is, the driven roller 22, the setting operation position for performing the setting operation for selecting the one state in the pressing force setting unit 25, and the adjusting operation position for performing the adjustment operation for adjusting the one state in the pressing force adjusting unit 428. However, in the −Y direction as the predetermined direction, the driven roller 22, the setting operation position, and the adjustment operation position are arranged in this order.

That is, the driven roller support member 426 can rotate about the support member rotation shaft 261 that supports the driven roller support member 426 as a rotation shaft, and the pressing force adjusting unit 428 causes the driven roller support member 426 to rotate Y. In a plane parallel to the -Z plane, locking holes 4281 are provided as a plurality of locking points for locking the other end 27b of the coil spring 27.

According to the transport unit 420 as the media transport mechanism according to the present modification, since the adjustment operation position is not located between the driven roller 22 and the setting operation position, the adjustment work for adjusting the pressing force of the driven roller 22 is performed. Can be facilitated. Further, the expansion/contraction direction of the coil spring 27 and the expansion/contraction length adjustment direction can be configured to be within a plane parallel to the plane on which the driven roller support member 426 supporting the driven roller 22 rotates. As a result, the coil spring 27 prevents the driven roller support member 426 that supports the driven roller 22 from being twisted and allows the drive roller 21 to be pressed from a predetermined direction.
In addition, in the example shown in FIG. 6, the plurality of locking holes 4281 are provided in one row along the Z-axis direction, but may be configured in a plurality of rows whose positions in the Z-axis direction are different for each row. ..

(Modification 2)
In each of the above-described embodiments and modified examples, in each driven roller support member, support as a fulcrum is provided between the rotary shaft 221 of the driven roller 22 as an action point and the force point where the elastic force generated by the coil spring 27 acts. Although the first type of lever provided with the member rotation shaft has been described, in the −Y direction, which is the predetermined direction, the driven roller 22, the setting operation position, and the adjustment operation position are arranged in this order. The seed lever is not limited to the configuration. The driven roller support member may have a second type lever configuration or a third type lever configuration.

FIG. 7 is a side view showing the configuration of the transport unit 520 as a media transport mechanism according to Modification 2.
The transport unit 520 is an example of a media transport mechanism in the case where the driven roller support member 526 has a third-type lever configuration.
The transport unit 520 includes a drive roller 21, a driven roller 22, a driven roller support member 526, a coil spring 527, a pressing force setting unit 525, and a pressing force adjusting unit 528.
The driven roller support member 526 is rotatable in the YZ plane about a support member rotation shaft 5261 extending in the X axis direction.
The coil spring 527 is arranged so that a pressing force acts between the support member rotating shaft 5261 serving as a fulcrum and the rotating shaft 221 of the driven roller 22 serving as an action point. The coil spring 527 is a push spring, whereas the coil spring 27 is a tension spring.

The pressing force setting unit 525 is a mechanism that selectively sets the pressing force of the driven roller 22, and the position of the cam 251 and more specifically the position of the cam rotation shaft 253 sets the pressing force in the pressing force setting unit. It corresponds to the setting operation position where the setting operation is performed.
The pressing force adjusting unit 528 is a mechanism that adjusts the set pressing force by adjusting one state of the coil spring 527, that is, one selected length, and has the same configuration as the pressing force adjusting unit 328. Is. Therefore, the position at which the female screw of the pressing force adjustment unit 528 is rotated is the adjustment operation position.

Even in the case of the third type lever structure shown in FIG. 7 or the second type lever structure different from this, the driven roller 22, the setting operation position, and the adjustment operation are performed in the −Y direction as the predetermined direction. With the configuration in which the positions are arranged in order of position, it is possible to facilitate the adjustment work for adjusting the pressing force of the driven roller 22.

(Other modifications)
Although the coil spring is used as the elastic member in the above-described embodiments and modifications, the elastic member may be a coil spring as long as the elastic member generates a pressing force applied to the driven roller 22 with respect to the drive roller 21. It is not limited. For example, the elastic member may be a leaf spring or rubber.
Further, in the above-described embodiment and modified examples, the configuration in which the pressing force setting unit has the cam 251 has been described as an example, but the pressing force setting unit is a mechanism that can selectively set the pressing force of the driven roller 22. The structure having the cam 251 is not necessarily required. For example, a configuration may be employed in which a spacer whose height can be selectively changed is provided at the position of the cam 251.
Further, the above-described embodiment and modification are not limited to the case where the variation of the pressing force between the individual driven rollers 22 is adjusted within a predetermined allowable range, but the pressing force applied by one driven roller 22 is set to a predetermined pressing force. It can also be used when adjusting to a pressure.

The contents derived from the embodiment will be described below.

The media transport mechanism of the present application is connected to a drive roller that transports a medium, a driven roller that presses the medium against the drive roller, and a support portion that supports the driven roller, and an elasticity that applies a pressing force to the driven roller. A member and a pressing force setting unit that sets a pressing force corresponding to the selected one state by selecting one state from a plurality of states of the elastic member, and the selected elastic member. A pressing force adjusting unit for adjusting the set pressing force by adjusting the one state, and performing a setting operation for selecting the one state in the driven roller and the pressing force setting unit. A setting operation position and an adjustment operation position for performing an adjustment operation for adjusting the one state in the pressing force adjusting unit are arranged in a predetermined direction in the order of the driven roller, the setting operation position, and the adjustment operation position. It is characterized by

According to the configuration of this media transport mechanism, the driven roller, the setting operation position for performing the setting operation for selecting the one state in the pressing force setting unit, and the adjusting operation for adjusting the one state in the pressing force adjusting unit are provided. The adjustment operation position to be performed is arranged in the predetermined direction in the order of the driven roller, the setting operation position, and the adjustment operation position. Since the adjusting operation position is not arranged between the driven roller and the pressing force setting section, when this media transport mechanism is incorporated as a mechanism for transporting media in the printing apparatus, for example, the outside of the printing apparatus It is easy to access the adjustment operation position from, and the printing apparatus can be configured. As a result, the adjustment work for adjusting the pressing force of the driven roller can be facilitated.

The medium transport mechanism of the present application is a coil that is connected to a drive roller that transports a medium, a driven roller that presses the medium against the drive roller, and a support portion that supports the driven roller, and that applies a pressing force to the driven roller. A spring and a pusher having a cam for setting a pushing force corresponding to the selected one length state by selecting one length state from a plurality of length states of the coil spring. A pressure setting unit and a pressing force adjusting unit that adjusts the set pressing force by adjusting the one length of the coil spring, the driven roller, the cam, and the pressing force. The adjustment operation position for performing the adjustment operation for adjusting the one length in the adjustment unit is arranged in the predetermined direction in the order of the driven roller, the cam, and the adjustment operation position.

According to this configuration of the media transport mechanism, the driven roller, the cam included in the pressing force setting unit, and the adjusting operation position for performing the adjusting operation for adjusting one length selected by the pressing force adjusting unit are set to predetermined positions. In the direction, the driven roller, the cam, and the adjusting operation position are arranged in this order. Since the adjusting operation position is not arranged between the driven roller and the cam, the adjusting operation is performed from the outside of the printing device when the media feeding mechanism is incorporated as a mechanism for feeding the medium in the printing device, for example. The printing device can be configured so that the position can be easily accessed. As a result, the adjustment work for adjusting the pressing force of the driven roller can be facilitated.

In the media transport mechanism, the position of one end of the coil spring is selectively set by the rotation of the cam, and the other end of the coil spring is set by the adjustment of the pressing force adjusting unit. It is preferable that the connection position where the support portion is connected is adjusted.

According to this configuration, the position of one end of the coil spring is selectively set by the rotation of the cam of the pressing force setting unit, and the other end of the coil spring is adjusted by the adjustment of the pressing force adjusting unit. The connection position to be connected is adjusted. That is, the position where the pressing force setting unit that sets the pressing force applied to the driven roller acts and the position where the pressing force adjusting unit that adjusts the pressing force acts may be configured separately on both ends of the coil spring. Therefore, the media transport mechanism can be configured with a simpler structure.

In the above-described media transport mechanism, the support portion is rotatable about a first shaft that supports the support portion as a rotation axis, and the pressing force adjusting portion is a second shaft supported by the support portion. A rotary member that is rotatable about the second shaft as a rotary shaft, and the other end of the coil spring is connected to the end of the rotary member. Preferably has a fitting portion fitted and fixed to the support portion at a plurality of rotation positions.

According to this configuration, the other end of the coil spring is connected to the end of the rotating member that is rotatable about the second shaft supported by the support portion that supports the driven roller, and the rotation is performed. The member has a fitting portion that is fitted and fixed to the support portion at a plurality of rotation positions. Therefore, by rotating the rotating member, it is possible to adjust the connecting position connected to the supporting portion while the other end of the coil spring is connected to the end of the rotating member. Further, the adjustment of the connecting position can be performed by selecting from a plurality of rotating positions where the rotating member is fitted and fixed to the supporting portion.

In the above-described media transport mechanism, the support section is rotatable about a first axis that supports the support section as a rotation axis, and the pressing force adjusting section is parallel to a plane on which the support section rotates. It is preferable to have a plurality of locking portions for locking the other end of the coil spring in the plane.

According to this structure, a plurality of locking points for locking the other end of the coil spring are provided in a plane parallel to the plane on which the support section that supports the driven roller rotates. Therefore, the expansion/contraction direction of the coil spring and the adjustment direction of the expansion/contraction length can be configured to be within a plane parallel to the plane on which the support portion supporting the driven roller rotates. As a result, the coil spring can press the drive roller from a predetermined direction without twisting the support portion that supports the driven roller.

A printing apparatus of the present application is characterized by including the above-described media transport mechanism and a printing unit that prints on a medium.

According to this configuration, it is possible to provide the printing apparatus in which the adjustment work for adjusting the sandwiching force of the drive roller and the driven roller that sandwich and convey the medium can be easily performed.

DESCRIPTION OF SYMBOLS 1... Roll paper, 10... Printing part, 11... Print head, 12... Carriage, 13... Guide shaft, 14... Carriage motor, 20... Conveying part, 21... Driving roller, 22... Followed roller, 23... Conveying motor, 24 ... Support base, 25... Pressing force setting section, 26... Follower roller supporting member, 28... Pressing force adjusting section, 30... Unwinding section, 31... Unwinding reel, 32... Unwinding motor, 40... Winding up section, 41 ... take-up reel, 42... take-up motor, 50... support frame, 60... transport support section, 61... platen, 62... medium support section, 70... control section, 71... input/output section, 72... CPU, 73... memory , 75... Head drive section, 76... Motor drive section, 77... System bus, 100... Printer, 211... Rotation axis, 221... Rotation axis, 251... Cam, 251a... Cam outer peripheral surface, 252... Cam bar, 252a... Contact Surfaces 253...Cam rotation shafts, 254...Cam bar rotation shafts, 261...Support member rotation shafts, 281...Pressure force adjusting plates, 282...Adjustment plate rotating shafts, 283...Fitting portions, 283a...Fitting holes, 320... Part, 325... pressing force setting part, 326... driven roller supporting member, 328... pressing force adjusting part, 420... conveying part, 426... driven roller supporting member, 428... pressing force adjusting part, 520... conveying part, 525... pressing Pressure setting part, 526... Followed roller supporting member, 528... Pressing force adjusting part, 3252... Cam bar, 3252a... Abutment surface, 3281... Cam bar rotating shaft, 3282... Shaft supporting part, 3283... Screw mechanism, 4281... Locking hole 5261... Support member rotating shaft.

Claims (6)

A drive roller that conveys media,
A driven roller that presses the medium against the drive roller,
An elastic member that is connected to a support portion that supports the driven roller and that applies a pressing force to the driven roller,
A pressing force setting unit that sets a pressing force corresponding to the selected one state by selecting one state from a plurality of states of the elastic member;
A pressing force adjusting unit that adjusts the set pressing force by adjusting the selected one state of the elastic member,
The driven roller, a setting operation position for performing a setting operation for selecting the one state in the pressing force setting unit, and an adjustment operation position for performing an adjustment operation for adjusting the one state in the pressing force adjusting unit, In a predetermined direction, the driven roller, the setting operation position, and the adjustment operation position are arranged in this order, the media transport mechanism. A drive roller that conveys media,
A driven roller that presses the medium against the drive roller,
A coil spring that is connected to a support portion that supports the driven roller, and that applies a pressing force to the driven roller;
A pressing force setting unit having a cam for setting a pressing force corresponding to the selected one length state by selecting one length state from a plurality of length states of the coil spring. When,
A pressing force adjusting unit for adjusting the set pressing force by adjusting the one length of the coil spring,
The driven roller, the cam, and an adjusting operation position for performing an adjusting operation for adjusting the one length in the pressing force adjusting unit are arranged in a predetermined direction so as to correspond to the driven roller, the cam, and the adjusting operation position. A media transport mechanism characterized by being arranged in order. By the rotation of the cam, the position of one end of the coil spring is selectively set,
The media transport mechanism according to claim 2, wherein the connection position at which the other end of the coil spring is connected to the support portion is adjusted by adjusting the pressing force adjustment portion. The support portion is rotatable about a first shaft supporting the support portion as a rotation shaft,
The pressing force adjusting unit includes a second shaft supported by the supporting unit, and a rotating member rotatable about the second shaft as a rotating shaft.
The other end of the coil spring is connected to the end of the rotating member,
The media transport mechanism according to claim 3, wherein the rotating member has a fitting portion that is fitted and fixed to the support portion at a plurality of rotating positions. The support portion is rotatable about a first shaft supporting the support portion as a rotation shaft,
The pressing force adjusting portion has a plurality of locking portions for locking the other end portion of the coil spring in a plane parallel to a plane on which the support portion rotates. The described media transport mechanism. A printing apparatus, comprising: the medium transport mechanism according to claim 1; and a printing unit that prints on a medium.

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