JP6900925B2 - Printing equipment - Google Patents

Description

The present invention relates to a printing apparatus that prints using a thermal head.

A printing device that allows the thermal head to swing with respect to the platen roller has been proposed. For example, Patent Document 1 discloses a printing apparatus including a head mounting plate that can rotate about a support shaft and a compression coil spring. A line thermal head is attached to the head mounting plate. The line thermal head moves in the direction of approaching and away from the platen roller according to the rotation of the head mounting plate. The compression coil spring uniformly presses the heating element portion of the line thermal head toward the platen roller side via the head mounting plate.

Japanese Unexamined Patent Publication No. 2012-106511

The distance between the platen roller and the thermal head during printing varies depending on the thickness of the printing medium. In the case of the printing apparatus described in Patent Document 1, the rotation angle of the head mounting plate changes according to the fluctuation of the distance between the platen roller and the thermal head. In this case, the contact position of the thermal head with the print medium changes according to the rotation angle of the head mounting plate. Therefore, there is a problem that the contact position of the print medium with respect to the thermal head is not stable and the print quality may be deteriorated.

An object of the present invention is to provide a printing apparatus capable of maintaining print quality even if the thickness of a printing medium changes when the thermal head is rotatably supported by a platen roller.

The printing apparatus in the present invention is a roller that is rotatable about a first axis and a head holding portion that is rotatably supported around a second axis that extends parallel to the first axis. A head holding portion that holds a thermal head having a shaft and a plurality of heat generating elements arranged in parallel with the second shaft, and has a contact portion capable of defining the position of the thermal head, and a rotation of the head holding portion. It has a positioning portion that is arranged on the first axis side of the second axis in the radial direction about the second axis during movement and can contact the contact portion of the head holding portion. In the printing apparatus, the head holding portion is rotatable between a first state close to the roller and a second state separated from the roller, and the positioning portion is in the first state. wherein said head holding portion abutting portion abuts the first abutted position, abuts with the abutting portion and the second abutted position of the head holding unit in the second state, the first to be equivalent It has a positioning plane that is a plane that passes through the contact position and the second contacted position, and the second contacted position is a second that passes through the plurality of heat generating elements and the second axis in the first state. The head holding portion is arranged on the side opposite to the second axis with respect to the second virtual plane orthogonal to the first virtual plane and passing through the first contacted position, and the head holding portion is in the first state and the second state. It is characterized in that the rotation angle when rotating between the two is the same as the angle formed by the positioning surface with respect to the second virtual plane.

The printing apparatus has a head holding portion that is rotatable about a second axis. When the head holding portion is in the first state close to the roller, the contact portion is in contact with the first contact position of the positioning portion, and when the head holding portion is separated from the roller, the second state of the positioning portion is in contact. The contact portion comes into contact with the contacted position. Here, the second contacted position is arranged on the side opposite to the second axis with respect to the second virtual plane. In the process of changing from the first state to the second state, the head holding portion moves to the side opposite to the second axis side in the direction orthogonal to the second virtual plane (specific direction). If the above movement does not occur in the head holding portion, the positions of the plurality of heat generating elements in a specific direction change. On the other hand, in the printing apparatus, by moving the head holding portion in a specific direction, a state in which a plurality of heat generating elements of the head holding portion face the rollers is displayed between the first state and the second state of the head holding portion. It can be maintained in the process of rotating with. Therefore, in the printing apparatus, even when the head holding portion rotates in response to a change in the thickness of the printing medium, a plurality of heat generating elements can be appropriately brought into contact with the printing medium, so that good print quality is maintained. it can.

It is a perspective view of the printing apparatus 1A. It is a perspective view of a roller 2, a head holder 3, a path member 4, and a pair of positioning portions 5. It is the figure which looked at the roller 2, the head holder 3, and a pair of positioning portions 5 from the lower side. It is a left side view of a roller 2, a head holder 3, a path member 4, and a pair of positioning portions 5. It is a figure which looked at the roller 2, the head holding part 3B, and a pair of positioning parts 5 from the upper side. It is sectional drawing which saw the AA line of FIG. 2 from the direction of an arrow. It is a figure which shows the mode that the head holding part 3B rotates between the 1st state S1 and the 2nd state S2. It is a left side view of a head holder 3, a path member 4, and a pair of positioning portions 5. It is a figure which shows the pair of positioning part 5 in the 1st modification. It is a figure which shows the pair of positioning part 5 in the 2nd modification. It is a right side view of the roller 2, the head holder 3, the path member 4, and the pair of positioning portions 5 in the third modification.

Hereinafter, the printing apparatus 1A according to the embodiment of the present invention will be described with reference to the drawings. In the following description, the lower right side, the upper left side, the upper right side, the lower left side, the upper side, and the lower side of FIG. 1 are defined as the right side, the left side, the rear side, the front side, the upper side, and the lower side of the printing apparatus 1A, respectively.

<Overview of printing device 1A>
As shown in FIG. 1, the printing apparatus 1A includes a housing 10A, a cover 10B, a panel 10C, a plurality of keys 11, a plurality of LEDs 12, a discharge port 13, a tray 14, and the like. The housing 10A has a box shape in which the upper portion is open. The housing 10A has a substantially rectangular shape in front view and plan view. The cover 10B is rotatably supported at the rear of the housing 10A. The cover 10B opens and closes the housing 10A by rotating the front end side up and down with a rotation shaft extending in the left-right direction as a fulcrum. The printing apparatus 1A executes printing in a state where the upper portion of the housing 10A is covered with the cover 10B. The panel 10C is provided on the front side of the cover 10B. The plurality of keys 11 are provided on the panel 10C and are arranged in the left-right direction. The plurality of keys 11 receive an input operation for the printing device 1A. The plurality of LEDs 12 are provided behind the plurality of keys 11 in the panel 10C.

The discharge port 13 is provided on the front side of a plurality of keys 11 in the panel 10C. The discharge port 13 extends in the left-right direction and discharges the printed medium M (see FIG. 2 and the like) after printing. The tray 14 supports the printed print medium M after printing, which is discharged from the discharge port 13. As shown in FIG. 2, it is premised that the print medium M in the present embodiment is a so-called die-cut label in which a die-cut thermal label Ma is attached to a release paper Mb. The print medium M is housed inside the printing apparatus 1A in a wound state. Hereinafter, the printed medium M in a wound state is referred to as a “roll”. As shown in FIG. 2, the printing apparatus 1A further includes a roller 2, a head holder 3, a path member 4, a pair of positioning portions 5, and the like inside.

<Roller 2>
As shown in FIG. 2, the roller 2 includes a first roller 21 and a set roller 24. The assembly roller 24 has a second roller 22 and a third roller 23. The first roller 21, the second roller 22, and the third roller 23 each have a columnar shape. The first roller 21, the second roller 22, and the third roller 23 can rotate about an axis extending in the left-right direction. Hereinafter, the axis that is the center of rotation of the first roller 21 is referred to as "first axis 21X". The axis that serves as the center of rotation of the second roller 22 is referred to as "second axis 22X". The axis that serves as the center of rotation of the third roller 23 is referred to as the "third axis 23X".

The first roller 21 is arranged below the thermal head 36 (described later) shown in FIGS. 3 and 4. The first roller 21 can convey the print medium M toward the front side or the rear side by sandwiching and rotating the print medium M with the thermal head 36. As shown in FIG. 4, the first roller 21 is closest to the thermal head 36 at the position N1 at the upper end of the peripheral surface, and comes into contact with the print medium M at the position N1 when the print medium M is conveyed. Hereinafter, the virtual plane in contact with the first roller 21 at the position N1 closest to the thermal head 36 among the peripheral surfaces of the first roller 21 is defined as the “virtual plane P11”. The virtual plane P11 extends horizontally at right angles to the vertical direction.

As shown in FIG. 2, a columnar rotating shaft 21A extends outward from both left and right ends of the first roller 21. The rotating shaft 21A is rotatably supported by the housing 10A (see FIG. 1). The first roller 21 rotates by transmitting the driving force of a motor (not shown) to the rotating shaft 21A. At the time of printing by the thermal head 36, the print medium M is conveyed toward the front side by the first roller 21. Hereinafter, the upstream side and the downstream side are defined with reference to the transport direction of the print medium M at the time of printing. The front side of the printing device 1A corresponds to the downstream side in the transport direction (hereinafter, simply referred to as “downstream side”), and the rear side of the printing device 1A is referred to as the upstream side in the transport direction (hereinafter, simply referred to as “upstream side”). ) Corresponds.

As shown in FIGS. 2 and 4, the set roller 24 is provided on the downstream side of the first roller 21. The second roller 22 and the third roller 23 of the assembled roller 24 face each other in the vertical direction. The second roller 22 is arranged above the third roller 23. As shown in FIG. 4, the diameter of the third roller 23 is smaller than the diameter of the first roller 21. The diameter of the second roller 22 is smaller than the diameter of the third roller 23. The second shaft 22X of the second roller 22 is arranged on the rear side in the front-rear direction with respect to the third shaft 23X of the third roller 23. Hereinafter, a virtual plane extending through the second axis 22X and the third axis 23X is defined as a “virtual plane P13”. The virtual plane P13 is slightly inclined in the counterclockwise direction when viewed from the left side with respect to a virtual plane (referred to as “virtual plane Pi”) orthogonal to the front-rear direction. Hereinafter, unless otherwise specified, the rotation direction (clockwise direction / counterclockwise direction) is defined on the assumption that the state is viewed from the left side. In other words, the direction orthogonal to the virtual plane P13 is slightly inclined in the counterclockwise direction with respect to the virtual plane P11 orthogonal to the vertical direction.

The position N2 of the peripheral surface of the second roller 22 that intersects the virtual plane P13 corresponds to the position of the second roller 22 that is closest to the third roller 23. The position N3 of the peripheral surface of the third roller 23 that intersects the virtual plane P13 corresponds to the position of the third roller 23 that is closest to the second roller 22. The positions N2 and N3 are both arranged below the virtual plane P11, that is, on the same side as the side on which the first axis 21X of the first roller 21 is arranged with respect to the virtual plane P11.

As shown in FIG. 2, a columnar rotating shaft 22A extends outward from both left and right ends of the second roller 22. A columnar rotating shaft 23A extends outward from both left and right ends of the third roller 23. The rotating shafts 22A and 23A are rotatably supported by the housing 10A (see FIG. 1). The second roller 22 and the third roller 23 rotate by transmitting the driving force of the motor (not shown) to the rotating shafts 22A and 23A. The second roller 22 and the third roller 23 can convey the print medium M to the upstream side or the downstream side by sandwiching the print medium M between them and rotating each of them. As shown in FIG. 4, when the print medium M is conveyed, the second roller 22 comes into contact with the print medium M at position N2, and the third roller 23 comes into contact with the print medium M at position N3. Hereinafter, the virtual plane in contact with the second roller 22 at the position N2 closest to the third roller 23 among the peripheral surfaces of the second roller 22 is defined as the “virtual plane P12”. The virtual plane P12 is orthogonal to the virtual plane P13 passing through the second axis 22X and the third axis 23X, and is slightly inclined in the counterclockwise direction with respect to the virtual plane P11 orthogonal to the vertical direction.

The transfer speed of the print medium M conveyed to the upstream side or the downstream side by the rotation of the first roller 21 is referred to as “V1”. The transfer speed of the print medium M conveyed to the upstream side or the downstream side by the rotation of the assembly roller 24 is referred to as “V2”. In this case, in the printing apparatus 1A, the rotation speed of the roller 2 is adjusted by a motor (not shown) so that V2 becomes faster than V1. Hereinafter, the rotation direction of the roller 2 when the print medium M is conveyed toward the downstream side is referred to as a "forward rotation direction", and the rotation direction of the roller 2 when the print medium M is conveyed toward the upstream side. Is called the "reversal direction".

<Path member 4>
As shown in FIGS. 2, 4 and 6, the path member 4 is provided on the rear side and the lower side of the first roller 21. The path member 4 has a bent plate shape. As shown in FIG. 4, the path member 4 has a first portion 41, a second portion 42, and a third portion 43. The first portion 41 extends from the rear end portion toward the front diagonally upper side. The second portion 42 bends from the front end portion of the first portion 41 and extends horizontally to the rear side of the first roller 21 to the front side. The third portion 43 bends downward from the front end portion of the second portion 42, and extends forward while curving downward along the peripheral surface of the first roller 21.

<Transfer route of print medium M>
The transport path of the print medium M transported by the roller 2 along the path member 4 extends in the front-rear direction while bending. The details are as follows. As shown in FIG. 4, the portion of the transport path of the print medium M on the upstream side of the first roller 21 is defined by the first portion 41 and the second portion 42 of the path member 4. The print medium M is fed toward the path member 4 from a roll housed in the rear side of the first portion 41 of the path member 4 inside the printing apparatus 1A. The transport path extends in the front-rear direction along the upper surfaces of the first portion 41 and the second portion 42 of the path member 4. The transport path bends at the connecting portion between the first portion 41 and the second portion 42 of the route member 4.

The portion of the transport path of the print medium M in the vicinity of the first roller 21 is defined as follows. The direction Y11 from the first roller 21 toward the upstream side along the transport path extends in the direction along the virtual plane P11 from the position N1 of the first roller 21 toward the upstream side. The direction Y11 corresponds to the traveling direction when the print medium M, which receives a force in response to the rotation of the first roller 21 in the reverse direction, is conveyed to the upstream side in the vicinity of the first roller 21.

On the other hand, the direction Y12 from the first roller 21 toward the downstream side along the transport path is inclined downward from the position N1 of the first roller 21 toward the downstream side with respect to the direction along the virtual plane P11. Extend. In other words, the direction Y12 is inclined to the side where the first axis 21X of the first roller 21 is arranged with respect to the virtual plane P11 and extends downstream with respect to the direction along the virtual plane P11. The direction Y12 corresponds to the traveling direction when the print medium M, which receives a force in response to the rotation of the first roller 21 in the forward rotation direction, is conveyed to the downstream side in the vicinity of the first roller 21.

The portion of the transport path of the print medium M in the vicinity of the set roller 24 is defined as follows. The direction Y21 from the assembled roller 24 toward the upstream side along the transport path extends in the direction along the virtual plane P12 from the position N2 of the second roller 22 toward the upstream side. In other words, the direction Y21 is inclined downward with respect to the direction along the virtual plane P11, that is, toward the side where the first axis 21X of the first roller 21 is arranged with respect to the virtual plane P11 and extends upstream. .. The direction Y21 corresponds to the traveling direction when the print medium M, which receives a force in response to the rotation of the assembly roller 24 in the reverse direction, is conveyed to the upstream side in the vicinity of the assembly roller 24.

On the other hand, the direction Y22 from the assembled roller 24 toward the downstream side along the transport path extends in the direction along the virtual plane P12 from the position N2 of the second roller 22 toward the downstream side. In other words, the direction Y22 extends upward with respect to the direction along the virtual plane P11. The direction Y22 corresponds to the traveling direction when the print medium M, which receives a force in response to the rotation of the assembly roller 24 in the forward rotation direction, is conveyed to the downstream side in the vicinity of the assembly roller 24. The print medium M printed by the thermal head 36, which will be described later, is conveyed downstream from the assembly roller 24 in the direction Y22 and is discharged from the discharge port 13 (see FIG. 1).

The transport path of the print medium M is a line segment extending along the direction Y11 from the position N1 of the first roller 21 toward the downstream side and a direction toward the upstream side from the position N2 of the second roller 22 of the assembled rollers 24. It bends at the intersection with the line segment extending along Y21. The transport path is arranged below the virtual plane P11.

<Head holder 3>
As shown in FIGS. 2 to 6, the head holder 3 has a base portion 3A, a head holding portion 3B, and a first biasing portion 3C (see FIGS. 4 to 6). The base 3A has a bent plate shape and has a first portion 31 and a second portion 32. The first portion 31 has a substantially rectangular shape in a plan view and is orthogonal to the vertical direction. The first portion 31 is arranged above the first roller 21. As shown in FIG. 3, the length of the first portion 31 in the left-right direction is longer than the length of the first roller 21 in the left-right direction. The front end portion of the first portion 31 is arranged on the front side of the front end portion of the first roller 21. As shown in FIGS. 2 and 4, the second portion 32 extends downward from the rear end portion of the first portion 31. As shown in FIG. 6, a recess 33 recessed toward the right side is provided at the left end portion of the second portion 32. The recess 33 extends to the center of the second portion 32 in the left-right direction. The inner wall portion of the recess 33 is curved in a convex shape. The inner wall portion of the recess 33 protrudes most inward at the central portion in the front-rear direction.

As shown in FIG. 5, the head holding portion 3B has a plate shape and has a third portion 34 and a fourth portion 35. The third portion 34 and the fourth portion 35 are orthogonal to each other in the vertical direction. The third portion 34 has a substantially rectangular shape in a plan view. The rear end portion of the third portion 34 extends in a direction in which it is inclined toward the center in the left-right direction. As shown in FIG. 3, the thermal head 36 is held on the lower surface of the third portion 34. The thermal head 36 is made of a rectangular substrate and is fixed to the third portion 34. The thermal head 36 is a so-called line thermal head, and has a plurality of heat generating elements 36A arranged linearly in the left-right direction on the lower surface. The thermal head 36 is arranged on the upper side of the first roller 21. The thermal head 36 prints on the heat-sensitive label Ma by heating a plurality of heat generating elements 36A in a state where the printing medium M is sandwiched between the first roller 21 and the thermal head 36. As shown in FIGS. 4 and 5, a contact portion 38 having a curved corner is provided at the front end portion of the third portion 34. As shown in FIG. 4, the contact portion 38 projects forward with respect to the first portion 31 of the base portion 3A and is arranged behind the assembly roller 24.

As shown in FIGS. 5 and 6, the fourth portion 35 extends from the center of the rear end portion of the third portion 34 in the left-right direction to the rear side. The fourth portion 35 enters the recess 33 provided in the second portion 32 of the base portion 3A from the front side and protrudes to the rear side of the second portion 32. The inner wall portion of the recess 33 comes into contact with the fourth portion 35 from above and below. The head holding portion 3B is supported with respect to the base portion 3A so as to be rotatable about the fourth axis 35X extending in the left-right direction and movable in the front-rear direction.

Hereinafter, as shown in FIG. 7, the state of the head holding portion 3B that is most rotated in the clockwise direction is referred to as “first state S1”. The head holding portion 3B approaches the first roller 21 in the first state S1 and extends horizontally in the front-rear direction. On the other hand, the state of the head holding portion 3B that rotates most in the counterclockwise direction when viewed from the left side is referred to as "second state S2". The head holding portion 3B is separated from the first roller 21 in the second state S2. The rotation angle of the head holding portion 3B that rotates between the first state S1 and the second state S2 is referred to as “θ1”.

As shown in FIGS. 5 and 6, the first urging portion 3C is provided on the upper surface of the third portion 34 of the head holding portion 3B. The first urging portion 3C is two compression springs arranged in the left-right direction. As shown in FIG. 4, the first urging portion 3C is interposed between the first portion 31 of the base portion 3A and the third portion 34 of the head holding portion 3B, and the head holding portion 3B is moved from the second state S2 to the second state S2. Bounce towards one state S1. The first urging unit 3C presses the plurality of heat generating elements 36A of the thermal head 36 against the print medium M from above with the print medium M sandwiched between the thermal head 36 and the first roller 21. Make them stick together.

Further, the head holding portion 3B is urged to the front side by a second urging portion (not shown). Although the details will be described later, when the head holding portion 3B is moved to the front side according to the urging force of the second urging portion, the contact portion 38 of the head holding portion 3B is rearward to the pair of positioning portions 5 described later. It is suppressed by contacting from.

<Pair of positioning units 5>
As shown in FIG. 2, the pair of positioning portions 5 have positioning portions 5A and 5B. The positioning portions 5A and 5B each have a substantially square plate shape. The positioning portion 5A is arranged on the front side near the left end portion of the contact portion 38 of the head holding portion 3B. The positioning portion 5B is arranged on the front side near the right end of the contact portion 38 of the head holding portion 3B. Further, as shown in FIG. 4, the pair of positioning portions 5 have a radius when the head holding portion 3B rotates between the first state S1 (see FIG. 7) and the second state S2 (see FIG. 7). In the direction, the head holding portion 3B is arranged on the front side of the fourth axis 35X, that is, on the first axis 21X side of the first roller 21 with respect to the fourth axis 35X. The radial direction corresponds to the direction extending from the fourth axis 35X toward the contact portion 38 among the directions extending in the direction orthogonal to the fourth axis 35X.

The contact portion 38 of the head holding portion 3B abuts on the rear surface of each of the positioning portions 5A and 5B from the rear side. The movement of the head holding portion 3B to the front side according to the urging force of the second urging portion (not shown) is regulated by the pair of positioning portions 5. The details are as follows. As shown in FIG. 7, each of the pair of positioning portions 5 abuts with the abutting portion 38 of the head holding portion 3B in the first state S1 at the first contacted position C1. Each of the pair of positioning portions 5 comes into contact with the contact portion 38 of the head holding portion 3B in the second state S2 at the second contacted position C2. The shape of the rear surface of each of the positioning portions 5A and 5B is such that at least in the portion between the first contacted position C1 and the second contacted position C2, the first contacted position C1 and the second contacted position C1 and the second contacted position C2. It has a planar shape that passes through position C2. Hereinafter, the portion between the first contacted position C1 and the second contacted position C2 on the rear surfaces of the positioning portions 5A and 5B is referred to as a “positioning plane 50”.

Hereinafter, a virtual plane that passes through the fourth axis 35X of the head holding portion 3B and extends along the head holding portion 3B in the first state S1 is defined as a “virtual plane P21”. The plate thickness of the head holding portion 3B and the thermal head 36 is very small with respect to the length between the fourth shaft 35X and the plurality of heat generating elements 36A. Therefore, the virtual plane P21 can be regarded as a virtual plane passing through the fourth axis 35X of the head holding portion 3B and the plurality of heat generating elements 36A of the head holding portion 3B in the first state S1. Further, a virtual plane orthogonal to the virtual plane P21 and passing through the first contacted position C1 is defined as a "virtual plane P22". In this case, the second contacted position C2 is arranged on the front side with respect to the virtual plane P22, in other words, on the side opposite to the fourth axis 35X with respect to the virtual plane P22. Further, when the angle formed by the virtual plane P22 and the positioning plane 50 is described as "θ2", θ2 is the rotation angle of the head holding portion 3B that rotates between the first state S1 and the second state S2. Consistent with θ1.

As shown in FIG. 7, when the head holding portion 3B rotates from the first state S1 to the second state S2, the contact portion 38 of the head holding portion 3B forms the positioning plane 50 of the pair of positioning portions 5. It moves from the first contacted position C1 to the second contacted position C2 while contacting. Here, as described above, the second contacted position C2 is arranged on the front side (opposite to the fourth axis 35X) with respect to the virtual plane P22 passing through the first contacted position C1. Therefore, when the contact portion 38 moves from the first contacted position C1 to the second contacted position C2 in response to the rotation of the head holding portion 3B, the head holding portion 3B moves to the front side (fourth axis). Move to the opposite side of 35X). When the movement of the head holding portion 3B in the front-rear direction is restricted, the positions of the plurality of heat generating elements 36A of the thermal head 36 in the front-rear direction move to the rear side according to the rotation of the head holding portion 3B. On the other hand, in the present embodiment, the positions of the plurality of heat generating elements 36A of the thermal head 36 in the front-rear direction are difficult to change because the head holding portion 3B moves to the front side in accordance with the rotation.

<Printing operation>
As the roller 2 is rotated in the forward rotation direction by a motor (not shown), the print medium M is unwound from the roll and is conveyed downstream along the conveying path. The print medium M passes between the thermal head 36 of the head holder 3 and the first roller 21. The thermal head 36 is pressed against the print medium M according to the urging force of the first urging portion 3C of the head holder 3. In this state, the plurality of heat generating elements 36A of the thermal head 36 are heated to print the print image on the label Ma of the print medium M. The printed medium M after printing passes between the second roller 22 and the third roller 23 of the set roller 24, is further conveyed to the downstream side, and is discharged from the discharge port 13.

In the above printing process, for example, as shown in FIG. 4, when the printing medium M1 having a thin relative thickness is used, the head holding portion 3B rotates clockwise and approaches the first state S1. On the other hand, for example, as shown in FIG. 8, when the print medium M2 having a large relative thickness is used, the head holding portion 3B rotates in the counterclockwise direction and approaches the second state S2. However, in either case, since the contact portion 38 of the head holding portion 3B moves along the positioning plane 50 of the pair of positioning portions 5, the head holding portion 3B also moves in the front-rear direction, so that a plurality of heat generating elements are generated. The movement of 36A in the front-rear direction is suppressed. Therefore, even if the head holding portion 3B rotates, the plurality of heat generating elements 36A can appropriately contact the print medium M and heat the label Ma under good conditions.

On the other hand, as the roller 2 is rotated in the reverse direction by a motor (not shown), the print medium M is conveyed upstream along the transfer path. Here, the transport path of the print medium M between the first roller 21 and the assembly roller 24 extends along the direction Y21 from the position N2 of the second roller 22 of the assembly roller 24 toward the upstream side, and extends upward. It bends to reach the first roller 21. That is, the print medium M passes through a position separated from the thermal head 36 and approaches the first roller 21 in the process of being conveyed upstream from the assembly roller 24. Therefore, the label Ma of the print medium M is unlikely to be caught by the thermal head 36.

<Action and effect of this embodiment>
The printing apparatus 1A has a head holding portion 3B that is rotatable about the fourth axis 35X and is movable in the front-rear direction. When the head holding portion 3B is in the first state S1 close to the first roller 21, the contact portion 38 comes into contact with the first contacted position C1 of the pair of positioning portions 5. On the other hand, in the second state S2, the contact portion 38 comes into contact with the second contacted position C2 of the pair of positioning portions 5. Here, the second contacted position C2 is opposite to the fourth axis 35X with respect to the virtual plane P22 passing through the first contacted position C1 on the front side with respect to the first contacted position C1. Placed on the side. Therefore, the head holding portion 3B moves to the side (front side) opposite to the fourth axis 35X side with respect to the virtual plane P22 in the front-rear direction in the process of rotating from the first state S1 to the second state S2. Therefore, the printing device 1A maintains a state in which the plurality of heat generating elements 36A of the thermal head 36 face the first roller 21 in the process of rotating the head holding portion 3B, and the plurality of heat generating elements 36A are placed on the virtual plane P21. It is possible to suppress the movement in the front-back direction along the line. Therefore, the printing apparatus 1A can maintain a state in which the plurality of heat generating elements 36A are appropriately in contact with the printing medium M even when the head holding portion 3B rotates according to the change in the thickness of the printing medium M. Good print quality can be maintained.

Each of the positioning planes 50 of the positioning portions 5A and 5B has a flat shape that passes through the first contacted position C1 and the second contacted position C2. In this case, the printing apparatus 1A can accurately maintain the state in which the plurality of heat generating elements 36A of the thermal head 36 face the first roller 21 with high accuracy, and at the same time, can easily manufacture a pair of positioning portions 5.

The angle θ2 formed by the virtual plane P22 passing through the first contacted position C1 and orthogonal to the front-rear direction and the positioning plane 50 is the head holding portion 3B that rotates between the first state S1 and the second state S2. Consistent with θ1, which is the rotation angle of. In this case, the printing device 1A suppresses the movement of the plurality of heat generating elements 36A in the front-rear direction in the process in which the head holding portion 3B rotates between the first state S1 and the second state S2, and the first roller 21 The thermal head 36 can be maintained in a state of facing each other.

<Modification example 1>
The pair of positioning portions 5 may not have a positioning plane 50 extending in a plane through the first contacted position C1 and the second contacted position C2. For example, as shown in FIG. 9, each rear surface of the pair of positioning portions 5 is a positioning curved surface 50A that curves convexly toward the front side from the first contacted position C1 to the second contacted position C2. May have. In other words, the positioning curved surface 50A may be separated from the virtual plane P22 as it goes from the first contacted position C1 to the second contacted position C2. Further, the curvature of the positioning curved surface 50A may be gradually increased from the first contacted position C1 to the second contacted position C2. In this case, the printing apparatus 1A can maintain the state in which the plurality of heat generating elements 36A face the first roller 21 with higher accuracy in the rotation process of the head holding portion 3B.

In the first modification, the curvature of the positioning curved surface 50A may be uniform from the first contacted position C1 to the second contacted position C2. On the other hand, the curvature of the positioning curved surface 50A may be gradually reduced from the first contacted position C1 to the second contacted position C2.

<Modification 2>
For example, as shown in FIG. 10, the pair of positioning portions 5 pass through the first contacted position C1 and the first plane 50B, which is a plane parallel to the virtual plane P22, and the second contacted position C2. Moreover, it may have a second plane 50C which is a plane parallel to the virtual plane P22. The first plane 50B and the second plane 50C may be formed in a stepped shape. In this case, the printing device 1A can stepwise adjust the positions of the plurality of heat generating elements 36A provided on the head holding portion 3B in the front-rear direction according to the rotational state of the head holding portion 3B. Therefore, for example, when printing is performed on the print media M1 and M2 having different thicknesses, the printing apparatus 1A steps the position of the head holding portion 3B according to the thickness of each of the print media M1 and M2. Can be adjusted.

In the second modification, the plane parallel to the virtual plane P22 is not limited to the first plane 50B and the second plane 50C, and three or more planes having different distances in the front-rear direction from the virtual plane P22. A flat surface may be provided.

<Modification example 3>
The printing apparatus 1B in the third modification will be described with reference to FIG. The printing apparatus 1B differs from the printing apparatus 1A in that it does not have a pair of positioning portions 5 and has a rotation path portion 26 instead of the second roller 22 of the set roller 24. Further, the shape of the path member 4 is different from that of the printing device 1A. Since the other configurations are the same as those of the printing apparatus 1A, the description thereof will be omitted.

The path member 4 has a fourth portion 44, a fifth portion 45, and a sixth portion 46 in addition to the first portion 41, the second portion 42, and the third portion 43. The fourth portion 44 extends horizontally from the front end portion of the third portion 43 to the front side. The fifth portion 45 bends downward from the front end portion of the fourth portion 44, and extends forward while curving downward along the peripheral surface of the third roller 23. The sixth portion 46 extends horizontally from the front end portion of the fifth portion 45 to the front side.

The rotation path portion 26 has a pinch roller 26A, a rotation portion 26B, and a contact portion 26C. The pinch roller 26A corresponds to the second roller 22 (see FIG. 2 and the like) in the printing apparatus 1A. The rotating portion 26B is rotatably supported by a rotating shaft 260 extending outward from the pinch roller 26A to the left and right, and extends toward the rear side. The print medium M is conveyed through a gap formed between the lower surface of the rotating portion 26B and the upper surface of the fourth portion 44 of the path member 4. That is, the lower surface of the rotating portion 26B and the upper surface of the fourth portion 44 of the path member 4 define the transport path of the print medium M on the downstream side of the first roller 21. The contact portion 26C projects from the rear end portion of the rotating portion 26B toward the rear side, and comes into contact with the front end portion of the third portion 34 of the head holding portion 3B from above.

For example, as shown in FIG. 11A, when the print medium M1 having a thin relative thickness is used, the head holding portion 3B rotates in the clockwise direction. The contact portion 26C moves downward in response to the rotation of the head holding portion 3B, and the rotating portion 26B rotates in the counterclockwise direction. In this case, the gap between the lower surface of the rotating portion 26B and the upper surface of the fourth portion 44 of the path member 4 becomes smaller. On the other hand, for example, as shown in FIG. 11B, when the print medium M2 having a large relative thickness is used, the head holding portion 3B rotates in the counterclockwise direction. The contact portion 26C moves upward in response to the rotation of the head holding portion 3B, and the rotating portion 26B rotates in the clockwise direction. In this case, the gap between the lower surface of the rotating portion 26B and the upper surface of the fourth portion 44 of the path member 4 becomes large.

As described above, the rotation path portion 26 adjusts the length of the transport path in the vertical direction on the downstream side of the first roller 21 by rotating the rotation portion 26B according to the thickness of the print medium M. it can. Therefore, the printing apparatus 1B can appropriately convey the printing medium M even when the printing media M having different thicknesses are used.

<Other variants>
The present invention is not limited to the above embodiment, and various modifications can be made. The printing apparatus 1A does not have to include the set roller 24, and the printing medium M may be conveyed only by the rotation of the first roller 21. In the above, the head holding portion 3B is rotatably supported around the fourth shaft 35X by being sandwiched from the vertical direction by the recess 33 provided in the second portion 32 of the base portion 3A. On the other hand, the head holding portion 3B may have a protruding portion protruding in the left-right outer direction along the fourth axis 35X. The base portion 3A may support the protrusion so as to be rotatable and movable in the front-rear direction. Instead of the pair of positioning portions 5, a positioning portion capable of contacting the head holding portion 3B over the entire area of the contact portion 38 in the left-right direction may be provided.

A head holding that rotates between θ2, which is an angle formed by a virtual plane P22 passing through the first contacted position C1 and orthogonal to the front-rear direction and a positioning plane 50, and between the first state S1 and the second state S2. It may be different from θ1 which is the rotation angle of the part 3B. In this case, θ2 may be larger or smaller than θ1.

The contact portion 38 of the head holding portion 3B may be provided at a location other than the front end portion of the third portion 34. For example, the contact portion 38 may project outward from the same position as the position where the plurality of heat generating elements 36A are provided in the front-rear direction on the left and right side surfaces of the third portion 34. The pair of positioning portions 5 may be provided on the outer side in the left-right direction with respect to the third portion 34 so that they can come into contact with the abutting portion 38. In this case, the distance in the front-rear direction between the fourth axis 35X of the head holding portion 3B and the plurality of heat generating elements 36A and the distance in the front-rear direction between the fourth axis 35X of the head holding portion 3B and the contact portion 38. Is almost the same. In this case, the printing device 1A can suppress the movement of the plurality of heat generating elements 36A in the front-rear direction in response to the rotation of the head holding portion 3B in the vicinity of the plurality of heat generating elements 36A. Therefore, the printing device 1A can more accurately maintain the state in which the plurality of heat generating elements 36A face the first roller 21 when the head holding portion 3B rotates.

<Others>
The first roller 21 is an example of the "roller" of the present invention. The fourth axis 35X is an example of the "second axis" of the present invention. The virtual plane P21 is an example of the "first virtual plane" of the present invention. The virtual plane P22 is an example of the "second virtual plane" of the present invention.

1A, 1B: Printing device 3B: Head holding part 3C: First urging part 4: Path member 5, 5A, 5B: Positioning part 21: First roller 21X: First axis 22: Second roller 22X: Second axis 23: Third roller 23X: Third axis 24: Assembly roller 35X: Fourth axis 36: Thermal head 36A: Multiple heat generating elements 38: Contact portion 50: Positioning plane 50A: Positioning curved surface 50B: First plane 50C: First 2 planes C1: 1st contact position C2: 2nd contact positions M, M1, M2: Print media P11, P12, P13, P21, P22: Virtual plane S1: 1st state S2: 2nd state Y11, Y12, Y21, Y22: Direction

Claims (2)

A roller that can rotate around the first axis,
A head holding portion rotatably supported around a second axis extending parallel to the first axis.
Holds a thermal head having a plurality of heat generating elements arranged in parallel with the first axis and the second axis, and
A head holding portion having a contact portion capable of defining the position of the thermal head,
It is arranged on the first axis side of the second axis in the radial direction about the second axis when the head holding portion is rotated, and can come into contact with the abutting portion of the head holding portion. A printing device having a positioning unit
The head holding portion is
It is rotatable between the first state close to the roller and the second state away from the roller.
The positioning unit is
In the first state, the head holding portion is in contact with the contact portion at the first contact position, and in the second state, the head holding portion is in contact with the contact portion at the second contact position.
It has a positioning plane that is a plane that passes through the first contacted position and the second contacted position.
The second contact position is
The side opposite to the second axis with respect to the second virtual plane orthogonal to the first virtual plane passing through the plurality of heat generating elements and the second axis in the first state and passing through the first contacted position. It is located in,
The feature is that the rotation angle when the head holding portion rotates between the first state and the second state and the angle formed by the positioning plane with respect to the second virtual plane match. Printing equipment. The printing apparatus according to claim 1, characterized in that the distance between the said second shaft to said thermal head, the distance between the said second shaft to said abutment portion are substantially the same.

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