Head unit

Abstract

To provide a head unit in which a structure for replacing a thermal head is simplified.SOLUTION: A head unit 40 is provided with a frame 60, a head assembly 41 removably supported by the frame 60, a positioning section for positioning the head assembly to a first position in a first direction which is the conveyance direction of a recording medium in a state where the head assembly 41 is mounted, a guide section for guiding the movement of the head assembly 41 to a second position which is further forward in the conveyance direction than the first position in the first direction and further away from the conveyance path of the recording medium than the first position in a second direction which intersects with the first direction and extends in the thickness direction of the recording medium when the head assembly 41 is detached, and a fulcrum section for changing the attitude of the head assembly 41 when the head assembly 41 moves from the first position to the second position.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present disclosure relates to a head unit. [Background technology]

[0002] Printers that print by pressing a substrate against a thermal head while transporting it are known (see, for example, Patent Document 1). The printer in Patent Document 1 includes a thermal head assembly having a thermal head main body and a head support plate to which the main body is fixed, and a head frame to which the thermal head assembly is attached. The thermal head assembly has a notch formed therein that engages with a guide pin provided on the head frame.

[0003] The head frame is also provided with a stopper for fixing the head support plate and a lever for disengaging the thermal head assembly. When the printer is in use, the head support plate is fixed in place by the stopper. When replacing the thermal head assembly, the lever is operated to release the thermal head assembly. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-324374 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the above-mentioned prior art, the structure for replacing the thermal head is complicated.

[0006] An object of the present disclosure is to provide a head unit with a simplified structure for replacing a thermal head. [Means for solving the problem]

[0007] The head unit of the present disclosure comprises a frame, a head assembly removably supported on the frame and equipped with a thermal head, a positioning section that positions the head assembly at a first position in a first direction that is the transport direction of the recording medium, a guide section that guides movement of the head assembly in a second direction that intersects the first direction and runs along the thickness direction of the recording medium to a second position that is farther from the transport path of the recording medium than the first position, and a fulcrum section that serves as a fulcrum for changing the posture of the head assembly when the head assembly moves from the first position to the second position. [Effects of the Invention]

[0008] According to the present disclosure, an object is to provide a head unit with a simplified structure for replacing a thermal head. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view of a printing device. [Figure 2] FIG. 2 is a perspective view of the main body and the lid, showing the lid in a closed state. [Figure 3] FIG. 2 is a perspective view of the main body and the lid, showing the lid in an open state. [Figure 4] FIG. [Figure 5] FIG. 4 is a cross-sectional view of the lid showing a state in which the head assembly is attached to the frame. [Figure 6] FIG. 10 is a cross-sectional view of the cover showing a state in which the head assembly is tilted. [Figure 7] FIG. 10 is a cross-sectional view of the lid showing a state in which the head assembly is further tilted. [Figure 8] FIG. 4 is a cross-sectional view of the cover showing a state in which the head assembly is arranged in the up-down direction. [Figure 9] FIG. 10 is a perspective view of the lid portion showing a state in which the head assembly has been removed. [Figure 10] FIG. 10 is a cross-sectional view of the cover showing a state in which the head assembly has been removed. [Figure 11] 10 is a cross-sectional view of the cover showing a state in which a head-connected FPC is inserted into the FPC connection portion. FIG. [Figure 12] FIG. 10 is a cross-sectional view of the cover showing a state in which the head-connected FPC is not inserted into the FPC connection portion. [Figure 13] 10 is a cross-sectional view of the lid portion showing a state in which the tip portion of the second projection of the head cover intersects with the head support plate. FIG. [Figure 14] 10 is a cross-sectional view of the lid portion showing a state in which the head support plate is tilted and the tip portion of the second projection of the head cover is not in contact with the head support plate. FIG. [Figure 15] FIG. 4 is a side view showing the side plate of the frame. DETAILED DESCRIPTION OF THE INVENTION

[0010] A head unit according to an embodiment of the present disclosure will be described below. In each drawing, three mutually orthogonal directions, the X-axis direction, the Y-axis direction, and the Z-axis direction, are sometimes indicated by arrows. The Z-axis direction is, for example, along the up-down direction.

[0011] [Outline of the printing device] A printing device 1 including a head unit 40 will be described. FIG. 1 is a perspective view of the printing device 1. FIG. 2 is a perspective view of the main body 2 and the lid 3, showing the lid 3 in a closed state. FIG. 3 is a perspective view of the main body 2 and the lid 3, showing the lid 3 in an open state. FIG. 4 is a perspective view of the lid 3. FIG. 5 is a cross-sectional view of the lid 3, showing the head assembly 41 attached to the frame 60. FIG. 6 is a cross-sectional view of the lid 3, showing the head assembly 41 tilted. FIG. 7 is a cross-sectional view of the lid 3, showing the head assembly 41 further tilted. FIG. 8 is a cross-sectional view of the lid 3, showing the head assembly 41 positioned vertically. FIG. 9 is a perspective view of the lid 3, showing the head assembly 41 removed. FIG. 10 is a cross-sectional view of the lid 3, showing the head assembly 41 removed. FIG. 11 is a cross-sectional view of the lid 3, showing the head-connecting FPC 110 inserted into the opening 120a of the FPC connection part 120. Fig. 12 is a cross-sectional view of the lid part 3 showing a state in which the head-connecting FPC 110 is not inserted into the opening 120a of the FPC connection part 120. Fig. 13 is a cross-sectional view of the lid part 3 showing a state in which the tip portion 97 of the second protrusion of the head cover 90 intersects with the head support plate 80. Fig. 14 is a cross-sectional view of the lid part 3 showing a state in which the head support plate 80 is tilted and the tip portion 97 of the second protrusion of the head cover 90 does not contact (intersect) with the head support plate 80. Fig. 15 is a side view showing the side plate 63 of the frame 60.

[0012] The printing device 1 is, for example, a thermal printer equipped with a thermal head 41h as shown in Fig. 5, and is used in multimedia stations (MMS), automated teller machines (ATMs), cash dispensers (CDs), ticket machines, cash registers, etc. installed in convenience stores. The printing device 1 conveys recording paper P (see Fig. 1), which is, for example, thermal paper, prints information such as letters and numbers on the recording paper P, and cuts it to output pieces of recording paper such as tickets and receipts.

[0013] As shown in FIG. 1, the printing device 1 includes a main body 2, a cover 3, a cutter blade 5, a base 6, and a recording paper holder 7, for example.

[0014] The lid unit 3 is provided openably and closably, for example, above the side of the main body 2 where the recording paper P is inserted. In Fig. 2, the lid unit 3 provided on the main body 2 is in a fully closed state, and in Fig. 3, the lid unit 3 is in a fully open state. The lid unit 3 has, for example, a rectangular planar shape with its longitudinal direction aligned with the width direction of the recording paper P, which is roll paper. The lid unit 3 is rotatable around a rotation axis 31 located in the X-axis direction.

[0015] As shown in Figure 3, the printing device 1 includes a head unit 40 and a platen unit 42. The head unit 40 includes a thermal head 41h (see Figure 5) that prints on the recording paper P. The platen unit 42 includes a platen roller 42r that transports the recording paper P. In the printing device 1, the head unit 40 is mounted on the lid part 3, and the platen unit 42 is mounted on the main body part 2. It is also possible that the head unit 40 is provided in the main body part 2, and the platen unit 42 is provided in the lid part 3.

[0016] A transport drive system including a motor and gears that rotates the platen roller 42r is provided in the main body 2. The printing device 1 prints on the recording paper P inserted between the platen roller 42r and the thermal head 41h while transporting the recording paper P.

[0017] The main body 2 and the cover 3 are provided with a cutter blade 5 for cutting the recording paper P after printing (see FIGS. 1 and 5).

[0018] 1, the base 6 is a rectangular plate-shaped member that serves as a base for the printing device 1. The main body 2 and a recording paper holder 7 are arranged adjacent to each other on the base 6. The recording paper holder 7 rotatably supports recording paper P, which may be, for example, roll paper.

[0019] [Lid] As shown in FIGS. 2 to 4, the lid unit 3 includes a lid main body 32 and a head unit 40. The lid main body 32 has a top plate 33, a front plate 34, and a rear plate 35. The thickness direction of the top plate 33 is along the Z-axis direction. The front plate 34 and the rear plate 35 are bent from both ends of the top plate 33 in the X-axis direction and extend in the Z-axis direction. The thickness direction of the front plate 34 and the rear plate 35 is along the X-axis direction. In the description of the lid unit 3, the terms X-axis direction, Y-axis direction, and Z-axis direction are used, but these refer to the X-axis direction, Y-axis direction, and Z-axis direction when the lid unit 3 is closed, as shown in FIG. 1. In addition, the terms "front" and "rear" are used, but these refer to the downstream side in the transport direction of the recording paper, with "front" referring to the "front" and the upstream side in the transport direction.

[0020] 4, the lid 3 has side plates 36 and 37 that face each other in the Y-axis direction. The side plates 36 and 37 are bent from both ends of the top plate 33 in the Y-axis direction and extend in the Z-axis direction. The thickness direction of the side plates 36 and 37 is along the Y-axis direction.

[0021] [Head unit] 5, the head unit 40 includes a frame 60, a spring 70, a head assembly 41, and a head cover 90. The head assembly 41 includes a thermal head 41h and a head support plate 80.

[0022] Frame As shown in Figures 4 and 5, the frame 60 includes a main body plate 61, side plates 62, 63, and a back plate 64. The thickness direction of the main body plate 61 is along the Z-axis direction. The side plates 62 and 63 are spaced apart in the Y-axis direction. The side plates 62 and 63 are bent from both ends of the main body plate 61 in the Y-axis direction and extend in the Z-axis direction. The thickness direction of the side plates 62 and 63 is along the Y-axis direction. The back plate 64 is bent from the front end of the main body plate 61 and extends in the Z-axis direction. The thickness direction of the back plate 64 is along the X-axis direction.

[0023] The frame 60 is attached to the inside of the lid 3. Specifically, a main body plate 61 of the frame 60 is attached to the inner surface of the top plate 33 of the lid 3. The frame 60 may be attached to the lid 3 via another member. The main body plate 61 is disposed opposite the top plate 33 in the Z-axis direction. The back plate 64 is disposed opposite the rear plate 35 in the X-axis direction.

[0024] The side plates 62 and 63 are formed with guide shapes for inserting the head support plate 80. The guide shapes provided on the side plates 62 and 63 will be described later.

[0025] [Spring] The spring 70 is attached to the main body plate 61 of the frame 60, as shown in FIG. 5, for example. The spring 70 is disposed between the main body plate 61 and the head assembly 41 in the Z-axis direction. The spring 70 presses the head assembly 41 toward the recording paper P. The spring 70 is, for example, a compression coil spring. The side of the spring 70 closer to the main body plate 61 is the base end, and the side closer to the head assembly 41 is the tip end. The inner diameter of the tip end of the compression coil spring is smaller than the inner diameter of the base end.

[0026] The spring 70 may pressurize the thermal head 41h via a head support plate 80 that supports the thermal head 41h. The spring 70 serves as a fulcrum for tilting the head assembly 41 when replacing the head assembly 41. This will be described in detail later. Note that "replacement" includes both installation and removal of the head assembly 41. The multiple springs 70 are arranged at predetermined intervals in the Y-axis direction. The spring 70 is an example of a fulcrum portion. The fulcrum portion is not limited to a compression coil spring, and may be, for example, another biasing member, and the biasing member may be, for example, a leaf spring.

[0027] [Thermal head] The thermal head 41h includes, for example, a substrate, a heating element, a driver IC, and an FPC connection portion 120. As shown in Figures 10 and 11, the FPC connection portion 120 is provided on the back side of the head assembly 41 and is connected to the head-connecting FPC 110. The FPC connection portion 120 has an opening 120a formed therein, into which the head-connecting FPC 110 is inserted. The back side of the head assembly 41 is the surface opposite the platen unit 42.

[0028] [Head support plate 80] 5, the head support plate 80 is plate-shaped and supports the thermal head 41h. The head support plate 80 has higher rigidity than the thermal head 41h and can suppress deformation of the thermal head 41h. The thermal head 41h is attached to the head support plate 80. The thermal head 41h is attached to the surface of the head support plate 80 opposite the spring 70.

[0029] The area of ​​the head support plate 80 may be larger than the area of ​​the thermal head 41h. The head support plate 80 has a main body portion 81 and a protruding portion 82. The main body portion 81 may be the portion on which the thermal head 41h is placed. The protruding portion 82 protrudes from the main body portion 81 in the X-axis direction. The protruding portion 82 may be formed in the center of the head support plate 80 in the Y-axis direction. The protruding portion 82 protrudes forward in the X-axis direction. When removing the head assembly 41 from the frame 60, the user can change the posture of the head assembly 41 by pressing the protruding portion 82.

[0030] As shown in FIG. 4, the head support plate 80 has a pair of protrusions 83, 84. The pair of protrusions 83, 84 protrude from the main body 81 in the Y-axis direction. The protrusions 83, 84 are inserted into a gap between a wall surface 65a (see FIG. 15) and a wall surface 66a (see FIG. 15), which will be described later. The protrusions 83, 84 protrude outward in the Y-axis direction beyond the side plates 62, 63. The protrusions 83, 84 also have a predetermined length in the X-axis direction.

[0031] 9 and 13, the head support plate 80 also has a protrusion 85. The protrusion 85 protrudes in the same direction as the protrusion 83. The protrusions 83 and 85 are spaced apart in the X-axis direction. The protrusion 85 is located closer to the rear plate 64 of the frame 60. A recess is formed between the protrusions 83 and 85. As shown in FIG. 13, a tip portion 97 of a second protrusion 94 of the head cover 90 (described later) can be inserted into the recess between the protrusions 83 and 85. The length of the protrusion 85 in the Y-axis direction is shorter than that of the protrusion 83. The protrusion 83 is formed to extend outward beyond the side plate 62, and the protrusion 85 is long enough not to come into contact with the side plate 62.

[0032] As shown in FIG. 5, the head support plate 80 also has a protruding portion 86. The protruding portion 86 protrudes in the X-axis direction opposite the protruding portion 82. In the state shown in FIG. 9, it protrudes in the Z-axis direction opposite the protruding portion 82. In the state shown in FIG. 5, the protruding portion 86 is engaged with the rear plate 64 of the frame 60. The rear plate 64 is provided with a locking portion 67 to which the protruding portion 86 is engaged. The locking portion 67 may be a locking claw, or may be an opening or recess into which the protruding portion 86 can be inserted. The protruding portion 86 is an example of a second protruding portion.

[0033] [Headcover] The head cover 90 is formed to cover a portion of the thermal head 41h. The head cover 90 is supported by a pair of side plates 36, 37 of the cover unit 3. The head cover 90 has a pin 91 that protrudes in the Y-axis direction. The pin 91 is inserted into a hole formed in the side plates 36, 37. The axis of the pin 91 is along the Y-axis direction. The head cover 90 can swing around the pin 91. The head cover 90 can protect, for example, terminals formed on the thermal head 41h. Figures 4 and 5 show the head cover 90 in a closed state. When the printing device 1 is in use, the head cover 90 is closed as shown in Figures 4 and 5. When replacing the head assembly 41, the head cover 90 is in an open state as shown in Figure 9.

[0034] As shown in FIG. 5, the head cover 90 has a cover body 92 and a first protrusion 93. The cover body 92 is formed so as to cover a portion of the thermal head 41h. When the head cover 90 is closed, the thickness direction of the cover body 92 is generally along the Z-axis direction. The thickness direction of the cover body 92 may be inclined with respect to the Z-axis direction. In other words, the surface of the cover body 92 may be inclined with respect to the XY plane. The cover body 92 extends in the X-axis direction from a position corresponding to the rear plate 35 toward the front plate 34. The cover body 92 is formed so as to cover approximately half of the thermal head 41h in the X-axis direction.

[0035] As shown in FIG. 4, the first protrusion 93 is formed to protrude in the Z-axis direction from the rear end of the cover main body 92. When the head assembly 41 is attached, the head support plate 80 abuts against the first protrusion 93, allowing the head cover 90 to swing and close as shown in FIG. 5. The multiple first protrusions 93 are spaced apart in the Y-axis direction. Openings are formed between the multiple first protrusions 93. In a normal state in which printing is possible on the recording paper P, the protruding portion 86 of the head support plate 80 may abut against the first protrusion 93.

[0036] 13, the head cover 90 has a second protrusion 94. The second protrusion 94 has a first portion 95 extending from the cover main body 92 in the Z-axis direction, a second portion 96 extending from the first portion 95 in the X-axis direction, and a tip portion 97 extending from the second portion 96 in the Z-axis direction. When the head cover 90 is closed, the tip portion 97 is disposed in the recess between the protrusions 83 and 85, as described above. When the head assembly 41 is attached to the frame 60, the tip portion 97 comes into contact with the protrusion 85 of the head support plate 80, thereby allowing the head support plate 80 to move rearward.

[0037] The tip portion 97 has a predetermined thickness. The thickness direction of the tip portion 97 is along the Y-axis direction. The tip portion 97 is formed with an inclined portion 98 that can come into contact with the protrusion 85. In the X-axis direction, the width of the tip side of the tip portion 97 is narrower than the width of the base end side of the tip portion 97. When viewed in the Y-axis direction, the inclined portion 98 is inclined with respect to the X-axis and Z-axis. When viewed in the Y-axis direction, the inclined portion 98 is not limited to being formed linearly, but may be formed in a curved shape.

[0038] When the head cover 90 is closed, the inclined portion 98 is located closer to the top plate 33 of the lid portion 3 than the head support plate 80. When the head cover 90 is closed, the tip portion 97 is located rearward of the spring 70.

[0039] [Head connection FPC] 10 and 11, the head-connecting FPC 110 is disposed so as to extend forward in the X-axis direction from the rear plate 64 of the frame 60. The thickness direction of the head-connecting FPC 110 is along the Z-axis direction. As described above, the head-connecting FPC 110 is inserted into the opening 120a of the FPC connection part 120.

[0040] [Frame guide shape] 15, the side plate 63 of the frame 60 has a first portion 65 and a second portion 66. The side plate 62 has the same shape as the side plate 63. The first portion 65 and the second portion 66 are spaced apart in the X-axis direction. The first portion 65 and the second portion 66 may be connected to each other.

[0041] Between the first portion 65 and the second portion 66, a guide groove is formed into which the protrusion 84 of the head support plate 80 is inserted when replacing the head assembly 41.

[0042] The first portion 65 has wall surfaces 65a, 65b, 65c, and 65d. In the Z-axis direction, the wall surfaces 65a, 65b, 65c, and 65d are formed in this order, with the wall surface 65d being located closest to the main body plate 61. The wall surfaces 65a, 65b, and 65d may be parallel to the YZ plane. "Parallel" includes "approximately parallel." The wall surface 65c is inclined with respect to the X-axis and Z-axis when viewed in the Y-axis direction. The wall surface 65a is located closer to the second portion 66 in the X-axis direction than the wall surfaces 65b, 65c, and 65d. The wall surface 65d is located farther from the second portion 66 in the X-axis direction than the wall surfaces 65a, 65b, and 65c.

[0043] The second portion 66 has wall surfaces 66a and 66b. The wall surface 66a is disposed opposite the wall surface 65a in the X-axis direction. The wall surface 66b is disposed closer to the main body plate 61 than the wall surface 66a in the Z-axis direction. The wall surface 66b is disposed opposite the wall surfaces 65b, 65c, and 65d in the X-axis direction. The wall surfaces 66a and 66b may be surfaces parallel to the YZ plane.

[0044] In the X-axis direction, the distance between wall surface 65a and wall surface 66a corresponds to the thickness of protrusion 84. The gap between wall surface 65a and wall surface 66a is large enough for protrusion 84 to pass through when protrusion 84 is arranged so that the thickness direction of protrusion 84 is along the X-axis direction.

[0045] The distance between wall surface 65b and wall surface 66b in the X-axis direction corresponds to the width of protrusion 84. The width of protrusion 84 may be the same as the width of protrusion 83 shown in Fig. 13. When head assembly 41 is attached to frame 60, protrusion 84 is disposed between wall surface 65b and wall surface 66b.

[0046] The end of wall surface 65c closer to wall surface 65d is positioned farther from wall surface 66b in the X-axis direction than the end of wall surface 65c closer to wall surface 65b. Wall surface 65c functions as a guide surface that guides the movement of protrusion 84 of head support plate 80 when head assembly 41 is removed from frame 60. The front end of protrusion 84 moves forward along wall surface 65c and also moves in a direction approaching main body plate 61. At this time, head support plate 80 is in an inclined state, as will be described later.

[0047] [Removing the head assembly] Next, the operation of removing the head assembly 41 will be described. When describing the operation of removing and installing the head assembly 41, the terms "upper" and "lower" are used, and these refer to the states shown in the respective drawings. In the Z-axis direction, the side closer to the main body plate 61 is referred to as "lower," and the side farther from the main body plate 61 is referred to as "upper." In the state shown in FIG. 5, the head support plate 80 is positioned below the thermal head 41h.

[0048] The thermal head 41h and the head support plate 80 move as a unit in the state of the head assembly 41. First, Fig. 5 shows the state in which the head assembly 41 is attached to the frame 60. At this time, the head support plate 80 is supported by the springs 70. Also, the protrusion 83 fits into the opening between the wall surfaces 65b and 66b of the side plate 62. The protrusion 84 fits into the opening between the wall surfaces 65b and 66b of the side plate 63.

[0049] When removing the head assembly 41, the posture of the head assembly 41 changes as shown in Figures 5 to 8. The user can release the fixed state of the head support plate 80 by pressing the protruding portion 82, and tilt the head assembly 41 as shown in Figure 6. At this time, the protruding portions 83 and 84 move downward and forward while contacting the wall surface 65c.

[0050] By pressing the overhanging portion 82 from above, the head support plate 80 tilts, with the point of contact with the spring 70 as the fulcrum. The overhanging portion 82 moves down, and the end of the head support plate 80 closer to the rear plate 64 moves up. At this time, as shown in FIG. 12 , the connection between the FPC connection portion 120 and the head-connecting FPC 110 is released. In this state, the head-connecting FPC 110 is removed from the opening 120a of the FPC connection portion 120.

[0051] 7, the protruding portion 82 moves until it hits the main body plate 61. At this time, the protruding portion 86 is positioned above the rear plate 64 and is not in contact with the rear plate 64.

[0052] 8, the user can stand the head support plate 80 upright so that it is aligned along the Z-axis direction. At this time, the thickness direction of the head support plate 80 is aligned along the X-axis direction. In addition, the protrusions 83 and 84 are located below the gap between the wall surface 65a and the wall surface 66a.

[0053] 8, by lifting up the head assembly 41, the head assembly 41 can be removed from the frame 60, as shown in Figures 9 and 10. At this time, the protrusions 83 and 84 pass through the gap between the wall surface 65a and the wall surface 66a and are lifted up.

[0054] [Installing the head assembly] Next, we will explain the operation when attaching the head assembly 41. As shown in Figures 9 and 10, head assembly 41 is placed in an upright position with overhanging portion 82 facing downward and overhanging portion 86 facing upward, and then protrusions 83 and 84 are inserted into the gap between wall surface 65a and wall surface 66a.

[0055] As shown in Figure 8, by pushing the head support plate 80 downward, the protruding portion 82 is pressed against the main body plate 61. As shown in Figure 7, by tilting the protruding portion 86 rearward, the head assembly 41 can be tilted. The protruding portion 82 is moved further forward in the state shown in Figure 7 than in the state shown in Figure 8. The protruding portion 82 abuts against the upper surface of the main body plate 61, and the tip of the spring 70 abuts against the head support plate 80.

[0056] As shown in FIG. 6 , by moving the overhanging portion 86 downward, the posture of the head support plate 80 can be changed with the spring 70 as a fulcrum. At this time, the protrusions 83 and 84 come into contact with the wall surface 65c, which guides the movement of the head support plate 80. The posture of the head support plate 80 changes so that the thickness direction of the head support plate 80 approaches the Z-axis direction. At this time, by closing the head cover 90, the tip portion 97 of the second protrusion 94 of the head cover 90 is inserted between the protrusions 83 and 85. As the tip portion 97 further moves downward, the tip portion 97 comes into contact with the protrusion 85, which moves rearward. As the head support plate 80 moves rearward, the thickness direction of the head support plate 80 is aligned with the Z-axis direction.

[0057] As shown in FIG. 12, the head-connecting FPC 110, which is located behind the opening 120a of the FPC connection portion 120, is inserted into the opening 120a as shown in FIG. 11. The protrusions 83 and 84 contact and are guided by the wall surface 65c, and then fit into the gap between the wall surface 65b and the wall surface 66b. This positions the head assembly 41 as shown in FIG. 5. In this state, the protrusion 85 is engaged with the engaging portion 67 of the rear plate 64.

[0058] [Effects of the head unit according to the embodiment] The head unit 40 according to the embodiment comprises a frame 60, a head assembly 41 removably supported on the frame 60 and equipped with a thermal head 41h, wall surfaces 65b, 66b which are positioning portions that position the head assembly 41 at a first position in the X-axis direction (first direction), which is the transport direction of the recording paper P (recording medium), wall surface 65c which is a guide portion that guides the movement of the head assembly 41 in the Z-axis direction (second direction), which intersects the X-axis direction and runs along the thickness direction of the recording paper P, to a second position (downward) which is a position further from the transport path of the recording paper P than the first position, and a spring (fulcrum portion) 70 which serves as a fulcrum that changes the posture of the head assembly 41 when the head assembly 41 moves from the first position shown in FIG. 5 to the second position shown in FIG. 7.

[0059] With this head unit 40, the head assembly 41 can be tilted by moving it along the wall surface 65c, and then removed from the frame 60. This simplifies the structure for removing the head assembly 41 from the frame 60. This eliminates the need for levers and the like used in conventional technology.

[0060] The head assembly 41 also includes a thermal head 41h and a head support plate 80 that supports the thermal head 41h, is disposed on the opposite side of the thermal head 41h from the transport path in the Z-axis direction, and is movable integrally with the thermal head 41h, and the fulcrum portion includes a spring (biasing member) 70 that biases the head support plate 80 so as to approach the transport path, and the head support plate 80 has, at the first position, a protruding portion (first protruding portion) 82 that protrudes in the X-axis direction to a position where it does not overlap with the thermal head 41h, and serves as a positioning portion. Wall surfaces 65b, 66b, which are the guide portions, come into contact with head support plate 80 to position head assembly 41 at the first position, and wall surface 65c, which is the guide portion, comes into contact with head support plate 80 to guide the movement of head assembly 41, thereby guiding the movement of head support plate 80. When head assembly 41 moves from the first position to the second position, spring 70 comes into contact with head support plate 80, and when protrusion portion 82 is pushed in the Z-axis direction in a direction away from the transport path, head assembly 41 changes its posture with spring 70 as the fulcrum.

[0061] With this configuration of the head unit 40, the head support plate 80, which is superimposed on the thermal head 41h, can be moved against the wall surface 65c, which serves as the guide portion, to change the posture of the thermal head 41h, thereby allowing the thermal head 41h to be removed from the frame 60.

[0062] The frame 60 also has a main body plate 61 that is arranged on the opposite side of the transport path from the thermal head 41h in the Z-axis direction, and a pair of side plates 62, 63 that are arranged apart from each other in the Y-axis direction (third direction) along the width direction of the recording paper P and that extend from the main body plate 61 in the Z-axis direction, and the pair of side plates 62, 63 are formed with wall surfaces 65b, 66b that serve as positioning portions and wall surface 65c that serves as a guide portion.

[0063] With the head unit 40 configured as described above, the head assembly 41 can be positioned by bringing the head support plate 80 into contact with the wall surfaces 65b, 66b formed on the pair of side plates 62, 63. With the head unit 40 configured as described above, the thermal head 41h can be replaced by moving the head assembly 41 while the head support plate 80 is abutting against the wall surfaces 65c formed on the pair of side plates 62, 63.

[0064] The head unit 40 also includes a head cover 90 that is connected to the frame 60 and can swing around a pin (rotation axis) 91 extending in the Y-axis direction. The head cover 90 has a cover main body (main body plate) 92 for covering the thermal head 41h, and a first protrusion 93 that protrudes in the Z-axis direction (thickness direction of the thermal head 41h) when the cover main body 92 covers the thermal head 41h. The head support plate 80 includes a protrusion (second protrusion) 86 that protrudes on the opposite side from the protrusion 82 in the X-axis direction. When the head assembly 41 is positioned at the first position and the cover main body 92 covers the thermal head 41h, the protrusion 86 abuts against the first protrusion 93. When the head support plate 80 abuts against the wall surface 65c, which is a guide portion, a gap is formed between the first protrusion 93 and the protrusion 86. In this state, the first protrusion 93 is not in contact with the protrusion 86 .

[0065] With this configuration of head unit 40, when attaching head assembly 41 to frame 60, protrusion 86 of head support plate 80 can be moved in the X-axis direction until it contacts first protrusion 93 of head cover 90.

[0066] Furthermore, in the head unit 40, the head cover 90 is arranged at a position farther away than the first protrusion 93, and has a tip portion 97 of a second protrusion 94 that protrudes from the pin 91 in the same direction as the first protrusion 93, and the tip portion 97 of the second protrusion 94 can abut against the head support plate 80 at a position closer to the pin 91 in the X-axis direction than the position where the spring 70 and the head support plate 80 abut. Specifically, the tip portion 97 can abut against a protrusion 85 that is arranged rearward of the spring 70.

[0067] With this configuration of the head unit 40, the tip portion 97 of the second protrusion 94 can be pressed against the head support plate 80 to move the head support plate 80 backward, and when attaching the head assembly 41, the thermal head 41h can be moved backward.

[0068] Furthermore, in the head unit 40, the spring 70 is disposed behind the wall surface 65c, which serves as a guide, in the X-axis direction. When replacing the thermal head 41h, the head support plate 80 can be tilted using the spring 70, which is disposed behind the wall surface 65c, as a fulcrum, to change the posture of the head support plate 80. After tilting the head support plate 80, the head assembly 41 can be removed from the frame 60.

[0069] Furthermore, in the head unit 40, the thermal head 41h has an FPC connection part 120 connectable to a flexible substrate, and the FPC connection part 120 is disposed rearward of the spring 70 in the X-axis direction. The FPC connection part 120 is disposed closer to the overhanging part 86 than the overhanging part 82 in the X-axis direction. In the head unit 40 having this configuration, the FPC connection part 120 and the head-connecting FPC 110 can be connected by moving the head support plate 80 rearward, and the connection between the FPC connection part 120 and the head-connecting FPC 110 can be released by moving the head support plate 80 forward.

[0070] In addition, the head support plate 80 includes a protruding portion (second protruding portion) 86 that protrudes on the opposite side to the protruding portion (first protruding portion) 82 in the X-axis direction, and the frame 60 has a locking portion 67 to which the protruding portion (second protruding portion) 86 is locked.

[0071] According to the head unit 40 having this configuration, in the normal state where printing is possible, the head support plate 80 can be locked to the locking portion 67 formed on the frame 60.

[0072] The configurations shown in the above embodiments are merely examples of the content of the present invention, and may be combined with other known technologies, or parts of the configurations may be omitted or modified within the scope of the gist of the present invention. [Explanation of symbols]

[0073] 1 printing device, 40 head unit, 41 head assembly, 41h thermal head, 60 frame, 61 main body plate (main body plate of frame), 65b, 66b wall surface (positioning portion), 67 locking portion, 70 spring (fulcrum portion), 86 protrusion portion (second protrusion portion), 90 head cover, 92 cover body, 93 first protrusion portion, 94 second protrusion portion, 120 FPC connection portion, XX axis direction (first direction), YY axis direction (third direction, width direction of recording paper), ZZ axis direction (second direction).

Claims

1. The frame and a head assembly removably supported by the frame and including a thermal head; a positioning unit that positions the head assembly at a first position in a first direction that is a conveyance direction of a recording medium; a guide portion that guides movement of the head assembly to a second position that is farther from a transport path of the recording medium than the first position in a second direction that intersects with the first direction and is along a thickness direction of the recording medium; a fulcrum portion that serves as a fulcrum for changing the attitude of the head assembly when the head assembly moves from the first position to the second position.

2. the head assembly includes the thermal head and a head support plate that supports the thermal head, is disposed on the opposite side of the transport path relative to the thermal head in the second direction, and is movable integrally with the thermal head; the fulcrum portion includes a biasing member that biases the head support plate so as to approach the transport path, the head support plate has a first protruding portion that protrudes in the first direction at the first position to a position where it does not overlap with the thermal head; the positioning portion positions the head assembly at the first position by contacting the head support plate; the guide portion abuts against the head support plate to guide the movement of the head assembly by guiding the movement of the head support plate; the biasing member is in contact with the head support plate when the head assembly moves from the first position to the second position, The head unit according to claim 1 , wherein the first protrusion is pushed in a direction away from the transport path in the second direction, thereby causing the head assembly to change position with the biasing member as a fulcrum.

3. the frame has a main body plate disposed on the opposite side of the transport path with respect to the thermal head in the second direction, and a pair of side plates disposed apart from each other in a third direction along the width direction of the recording medium and projecting from the main body plate in the second direction, The head unit according to claim 2 , wherein the pair of side plates are formed with the positioning portions and the guide portions.

4. a head cover connected to the frame and swingable about a rotation axis extending in a third direction along the width direction of the recording medium, the head cover having a main body plate for covering the thermal head and a first protrusion protruding in a plate thickness direction of the thermal head when the main body plate is covering the thermal head; the head support plate includes a second protruding portion that protrudes in a direction opposite to the first protruding portion in the first direction, When the head assembly is positioned at the first position and the main body plate covers the thermal head, the second protrusion abuts against the first protrusion, The head unit according to claim 2 , wherein a gap is formed between the first protrusion and the second protrusion when the head support plate is in contact with the guide portion.

5. the head cover has a second protrusion that is disposed at a position farther away than the first protrusion and that protrudes from the rotation shaft in the same direction as the first protrusion, The head unit according to claim 4 , wherein the second protrusion is capable of contacting the head support plate at a position closer to the rotation axis in the first direction than the position where the fulcrum and the head support plate contact each other.

6. The head unit according to claim 2 , wherein the fulcrum portion is disposed rearward of the guide portion in the first direction.

7. the thermal head has a connection portion connectable to a flexible substrate, The head unit according to claim 2 , wherein the connection portion is disposed rearward of the fulcrum portion in the first direction.

8. The head support plate includes a second protruding portion that protrudes in the opposite direction from the first protruding portion in the first direction. The head unit according to claim 2 , wherein the frame has a locking portion to which the second protrusion is locked.

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