JP2005028605A - Printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a printer in which contact pressure acting state or contact position of a print head can be adjusted for a sheet being inserted between a platen and the print head, and the adjusted state is sustained surely to ensure high precision printing operation stably over a long term. <P>SOLUTION: The printer comprises an urging member 272 for adjusting contact pressure acting state or contact position of a print head for a sheet being inserted between a platen and the print head, a cam 276, a cam follower 273, a member 274 for operating the cam 276, and a recess 278 and a protrusion 279 for holding the operating member 274 at a discontinuous operating position with feeling of click. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a printer having an adjustment mechanism for adjusting a contact pressure acting state or a contact position of the print head with respect to a sheet inserted between a platen and the print head.
[0002]
[Prior art]
Patent Document 1 discloses a screw type as a pressure adjusting means between the print head and the platen. That is, as shown in FIG. 8 of the document 1, the screw portion of the spring pressure adjusting screw (48) is screwed into the screw hole formed in the head pressing plate (38), and the screw (48). The tip of the is in contact with the upper surface of the spring pushing member (72). Between the head support plate (36) supporting the head (44) and the spring pushing member (72), a pressure spring (46) made of a coil spring is disposed. The elastic force of the pressure spring (46) can be adjusted by rotating the spring pressure adjusting screw (48). As shown in FIG. 9, the degree of adjustment can be confirmed by matching the scale (74) provided on the head pressing plate (38) with the index of the spring pressure adjusting screw (48).
[0003]
Further, Patent Document 2 discloses a lever type connected with a cam (pressure adjusting member) as a pressure adjusting means between the thermal head (14) and the platen (11). That is, as shown in FIG. 1 and FIG. 2 of the document 2, by rotating the lever (24), the cam (21, 21) connected to the lever (24) via the operation shaft (23). 22) rotates and presses the head support plate (12), whereby the pressing force of the thermal head (14) on the paper can be adjusted to be uniform.
[0004]
[Patent Document 1]
JP-A-3-270967 [Patent Document 2]
Japanese Patent Laid-Open No. 3-23443
[Problems to be solved by the invention]
In the conventional configuration disclosed in Patent Document 1, the adjustment screw (48) is urged by the pressurizing spring (46). 48) may gradually loosen. Further, when the adjusting screw (48) receives an unintended external force such as an operator coming into contact, the rotating position of the adjusting screw (48) may be shifted. As a result, the pressure applied to the print head may change, leading to a decrease in printing accuracy.
[0006]
Further, Patent Document 2 does not disclose any means for holding the operation position of the lever (24). Therefore, the lever (24) can be easily moved by vibration during operation of the printer or an unintended external force. As a result, the pressure applied to the print head may change, leading to a decrease in printing accuracy.
[0007]
The present invention has been made in view of such circumstances, and the contact pressure acting state or the contact position of the print head can be adjusted with respect to the paper inserted between the platen and the print head, and the adjustment has been made. It is an object of the present invention to provide a printer capable of reliably maintaining a state and performing a high-precision printing operation stably over a long period of time.
[0008]
[Means for Solving the Problems]
To achieve the above object, the present invention provides an adjustment mechanism for adjusting a contact pressure acting state or a contact position of a print head with respect to a sheet inserted between a platen and the print head, and the adjustment mechanism. And an operating position holding means for holding the operating member at a discontinuous operating position with a click feeling.
[0009]
By providing the operation position holding means, the operation position of the operation member is held by the holding means even when subjected to vibration or unintended external force during operation of the printer, and the contact pressure acting state of the print head or the appropriate contact position is maintained. The correct adjustment state is securely maintained. As a result, a highly accurate printing operation can be stably performed over a long period of time.
[0010]
Note that holding with a click feeling refers to a state in which a convex portion that has moved relative to the flat surface enters a concave portion formed on the flat surface and is held in the concave portion, and a similar state.
[0011]
Here, the adjustment mechanism engages with a spring member that urges the print head toward the platen side, a cam that is operated by the operation member, and a cam surface formed on the cam, and interlocks with the operation of the cam. A cam follower that expands and contracts the spring member to change the contact pressure acting state of the print head on the paper.
[0012]
In addition, the operation member may be formed in a disk shape, a cylindrical portion may be coaxially extended from one end surface thereof, and a tip end surface of the cylindrical portion may be formed on an inclined surface. The cylindrical portion constitutes a cam, and the inclined surface constitutes a cam surface. If comprised in this way, the number of parts will be small and the workability | operativity at the time of an assembly will improve.
[0013]
Furthermore, if a plurality of concave portions are formed on the cam surface and a convex portion that can be engaged with and disengaged from the concave portion is formed on the cam follower, the operation position holding means can be constituted by the concave portions and the convex portions, and the configuration is simple. The object of the present invention can be achieved.
[0014]
The adjustment mechanism includes a cam operated by the operation member, and a cam follower that engages with a cam surface formed on the cam and changes a contact position of the print head with respect to the paper in conjunction with the operation of the cam. It is good also as a structure including.
[0015]
In this case, the operation member can be formed in a disk shape, and a circumferential groove can be formed on one end surface thereof, and the cam can be configured by the circumferential groove. As a result, the number of parts is small, and the workability during assembly is improved.
[0016]
In addition, a support member for rotatably supporting the operation member and a cam follower is provided, and if the operation member and the cam follower are assembled to the support member to constitute a single unit, the assembly to the printer is possible. Workability is improved.
[0017]
Further, if a plurality of recesses are formed on the other end surface of the operation member or one of the support members at intervals in the circumferential direction, and a protrusion that can be freely attached to and detached from the recess is formed on the other side, the recess and the protrusion Thus, the operation position holding means can be configured, and the object of the present invention can be achieved with a simple configuration.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In the present embodiment, a configuration example in which the present invention is applied to a thermal label printer in which a line-shaped print head is arranged in the width direction of a sheet is shown.
[0019]
1 to 4 are perspective views showing an appearance of the printer according to the present embodiment.
The printer of this embodiment includes a printer main body 100, a head unit 200, and a sensor unit 300.
The upper surface of the printer main body 100 forms a paper transport path (paper transport path) (see, for example, FIG. 3), and a platen 110 that is a paper transport member is mounted on the paper transport path. The platen 110 is a cylindrical component whose outer surface is fitted with an elastic member. A sheet is sandwiched between the platen 110 and a print head 201 to be described later, and the sheet is conveyed as the platen 110 rotates.
[0020]
5 to 7 are diagrams showing a platen mounting structure.
As shown in FIG. 5, the platen 110 includes an elastic member 111 such as synthetic rubber on the outer periphery of the rotating shaft 112, and bearing members 113 and 114 are attached to both ends of the rotating shaft 112, respectively.
One bearing member 113 (the bearing member in the left direction in the figure) has a main body 115 and a mounting wing 116. The main body 115 supports one end of the rotating shaft 112 in a freely rotatable manner. Although not clearly shown in the drawing, the mounting wing portion 116 extends upward from the main body portion 115 in a wing shape, and this mounting wing portion 116 engages with the platen support portion 117 of the printer main body 100.
[0021]
As shown in FIG. 6, a notch groove 117 a and a platen support portion 117, which is a peripheral wall thereof, are formed at one side end of the printer main body 100 (see FIG. 6B). The formation part of the platen support part 117 is plate-shaped as shown in FIG. The bearing member 113 is inserted into the notch groove 117a, and the lower half circumferential portion of the main body 115 is supported by the bottom of the notch groove 117a. At the same time, the mounting wing 116 engages the inner side of the notch groove 117a, its peripheral wall, and the upper edge of the peripheral wall.
[0022]
The other bearing member 114 (the bearing member shown in the right direction in FIG. 5) includes a main body 118, a mounting wing 119, and a locking piece 120. The main body 118 rotatably supports one end of the rotating shaft 112. As shown in FIG. 5B, the mounting wing 119 extends upward from the main body 118 in a wing shape, and this mounting wing 119 engages with the platen support 121 of the printer main body 100. The locking piece 120 extends laterally from the main body 118, and an engagement protrusion 120a protrudes from one end surface thereof.
[0023]
As shown in FIG. 7, a notch groove 121a and a platen support portion 121 made up of its peripheral wall are also formed at the other side end portion of the printer main body 100 (see FIG. 7C). The formation part of the platen support part 121 is plate-shaped as shown in FIG. The bearing member 114 is inserted into the cutout groove 121a from above, and the lower half of the main body 118 is supported by the bottom of the cutout groove 121a. At the same time, the mounting wing part 119 engages with the inner part of the notch groove 121a and its peripheral wall.
[0024]
As shown in FIGS. 7A and 7B, the mounting wing portion 119 has an outer wall 119a, an inner wall 119b, and an upper wall 119c at left and right symmetrical positions, respectively, and the outer wall 119a, the inner wall 119b, Are formed at intervals corresponding to the thickness of the platen support 121. The upper and lower positions of the outer wall 119a and the inner wall 119b are such that the outer wall 119a is positioned below the inner wall 119b. Further, the upper wall 119c is continuous from the upper end of the inner wall 119b and is formed at a position above the intermediate portion between the outer wall 119a and the inner wall 119b.
The mounting wing portion 119 engages with the platen support portion 121 such that the peripheral wall of the notch groove 121a is fitted between the outer wall 119a and the inner wall 119b. Further, the upper wall 119 c is engaged with the upper end edge of the platen support portion 121.
[0025]
An engagement groove 121b is formed in the platen support part 121 on the side of the notch groove 121a. When the mounting wing part 119 is engaged with the platen support part 121 as described above, the engagement of the locking piece 120 is performed. The protrusion 120a engages with the engagement groove 121b. Thereby, the bearing member 114 is prevented from coming off from the platen support part 121.
When removing the bearing member 114 from the platen support 121, it is only necessary to bend the locking piece 120 to extract the engagement protrusion 120a from the engagement groove 121b and then move the bearing member 114 upward. Thereby, the engagement state with respect to the platen support part 121 of the mounting | wearing wing | blade part 119 is cancelled | released.
[0026]
According to the mounting structure of the platen 110 described above, since no special tool is required and the platen 110 can be attached to and detached from the printer main body 100, good maintainability can be ensured.
[0027]
Returning to FIGS. 1 to 4 again, the configuration of the head unit 200 and the sensor unit 300 will be described. A head support plate 210 is mounted on the lower surface of the head unit 200, and a line-shaped print head 201 is provided on the head support plate 210 (see, for example, FIG. 4). The head unit 200 has a base end attached to one end of the printer main body 100 via a support shaft 101, and rotates in an angular range from the closed position shown in FIG. 1 to the open position shown in FIG. It is free.
[0028]
Here, in the closed position shown in FIG. 1, the print head 201 is disposed at the print position. The print position is a position where the print head 201 is in contact with or close to the paper mounted on the paper transport path. On the other hand, in the open position shown in FIG. 3, the print head 201 is disposed at the retracted position. The retreat position is a position where the print head 201 is separated from the paper loaded on the paper transport path.
[0029]
The head unit 200 is always urged in the opening direction by an urging member including a coil spring or the like (not shown). Further, as shown in an enlarged view in FIG. 8, a braking protrusion 202 is provided at the base end of the head unit 200. On the other hand, a protrusion 102 a extending in an arc shape is formed around the support shaft 101 in the printer main body 100. A brake plate 102 is provided. The protrusion 102a bulges to the side facing the paper surface of FIG. These braking protrusions 202 and the braking plate 102 constitute a braking means for braking the head unit 200 that rotates in the opening direction by the biasing force of the biasing member.
[0030]
That is, the brake protrusion 202 rotates integrally with the head unit 200, and is slidably contacted with the protrusion 102a formed on the brake plate 102 on the way from the closed position to the open position, and then slidably contacted until reaching the open position. Followed. Thus, the braking protrusion 202 is slidably contacted with the protrusion 102a, so that the opening operation of the head unit 200 by the urging member is braked, and it is possible to avoid the danger that the head unit 200 moves vigorously and hits the person who operates.
[0031]
Next, the sensor unit 300 is provided with a sensor support plate 310, and a paper sensor 311 is mounted on the sensor support plate 310 (see FIG. 3). The sensor support plate 310 is movable in the longitudinal direction of the sensor unit 300.
The sensor unit 300 has a base end 300a attached to one end of the printer main body 100 via a support shaft (not shown), and an angle from the closed position shown in FIG. 1 to the open position shown in FIG. It is freely rotatable in the range. Here, the rotation center of the sensor unit 300 is set at a position shifted inward from the rotation center of the head unit 200.
[0032]
In the closed position shown in FIG. 1, the paper sensor 311 is disposed at the detection position. The detection position is a position where the paper sensor 311 contacts or approaches the paper loaded on the paper transport path. On the other hand, in the open position shown in FIG. 3, the paper sensor 311 is disposed at the non-detection position. The non-detection position is a position where the sheet sensor 311 is separated from the sheet mounted on the sheet conveyance path.
[0033]
A rod-shaped portion 320 extends in the axial direction from the other end of the sensor unit 300. On both side edges of the rod-shaped portion 320, ridges 321 extending in the axial direction in a region of a certain length from the base end are formed. Different positions of the protrusion 321 are first and second engaging portions 321a and 321b, respectively (see FIG. 9).
Further, as shown in FIGS. 1 to 4, a first locking member 220 is attached to the tip of the head unit 200. On the other hand, a second locking member 130 is attached to the side end of the printer main body 100 on the side where the head units 200 and the sensor unit 300 are close to and away from each other.
FIG. 9 is a perspective view showing the engagement / disengagement relationship between the first and second locking members and the first and second engaging portions formed in the sensor unit.
[0034]
The first locking member 220 provided in the head unit 200 is provided with a first recess 221 into which a rod-shaped portion 320 formed in the sensor unit 300 is fitted, and a first locking member is provided at an inner edge of the first recess 221. A claw 222 is formed. The first locking claw 222 is detachable from the first engagement portion 321a of the sensor unit 300.
[0035]
The second locking member 130 provided in the printer main body 100 is provided with a second recess 131 into which a rod-shaped portion 320 formed in the sensor unit 300 is fitted from above, and a second recess 131 is provided on the inner edge of the second recess 131. A locking claw 132 is formed. When the sensor unit 300 is in the closed position (that is, when the paper sensor 311 is in the detection position), the second engagement claw 132 is engaged with the second engagement portion 321b of the sensor unit 300 and the sensor unit 300 is engaged. 300 is fixed. The first and second recesses 131 and 221 are fitted to the rod-shaped portion 320 of the sensor unit 300 from opposite directions.
Here, the locking force of the first locking claw 222 with respect to the first engagement portion 321a is set larger than the locking force of the second locking claw 132 with respect to the second engagement portion 321b.
[0036]
As shown in FIG. 3, the lock member 140 is directed to the side end of the printer main body 100 (the side end on the side where the second locking member 130 is mounted), while the front end of the head unit 200. Further, a lock pin 230 that is engaged with and disengaged from the lock member 140 is provided so as to protrude. When the head unit 200 is in the closed position, the lock member 140 engages the lock pin 230 to hold the head unit 200 in the closed position (see FIG. 1).
[0037]
The printer of this embodiment having the above-described configuration can rotate the head unit 200 and the sensor unit 300 as follows.
First, as shown in FIG. 1, when each unit 200, 300 is in the closed position, as shown in an enlarged view in FIG. 9A, the first engaging portion 321a formed on the rod-shaped portion 320 of the sensor unit 300 While the first locking claw 222 of the head unit 200 is engaged, the second locking claw 132 of the printer main body 100 is engaged with the second engagement portion 321 b formed in the rod-shaped portion 320 of the sensor unit 300. Thereby, the sensor unit 300 is fixed to the printer main body 100, and the paper sensor 311 can hold the detection position.
[0038]
When the lock member 140 is operated from the state of FIG. 1 to release the locked state of the lock pin 230, the head unit 200 is rotated in the opening direction by a biasing force of a biasing member (not shown).
When the head unit 200 rotates in the opening direction, as described above, the locking force of the first locking claw 222 with respect to the first engagement portion 321a is the locking of the second locking claw 132 with respect to the second engagement portion 321b. Since it is larger than the force, the second locking claw 132 is detached from the second engagement portion 321b (see FIG. 9B). At this time, the first locking claw 222 remains locked to the first engaging portion 321a. Therefore, the sensor unit 300 rotates in the opening direction in conjunction with the rotation operation of the head unit 200 (see FIG. 2).
As described above, since the sensor unit 300 can be rotated in conjunction with the rotation operation of the head unit 200, it is possible to easily perform operations such as sheet replacement, thereby realizing good operability and maintainability. can do.
[0039]
When the head unit 200 continues to rotate, the rotation center of the sensor unit 300 is set to a position shifted inward from the rotation center of the head unit 200 as described above. The first concave portion 221 of the head unit 200 moves relative to the rod-shaped portion 320 in the axial direction. Then, when the head unit 200 rotates by a predetermined angle, the first locking claw 222 naturally disengages from the first engagement portion 321a (see FIG. 9C). Thereby, the unity between the sensor unit 300 and the head unit 200 is released (see FIG. 3).
The head unit 200 is braked and stopped by the sliding contact of the braking protrusion 202 shown in FIG. 8 with the protrusion 102a, and thereafter, the head unit 200 can be manually rotated to the rotating end and stopped at the open position.
[0040]
A guide bar 150 is arranged in the width direction on the upper surface of the printer main body 100 and below the paper transport path (see FIG. 3). A paper guide 151 that defines the paper width and a paper sensor 152 are movably mounted on the guide bar 150. When changing the paper, the paper guide 151 is moved in accordance with the width of the newly loaded paper, and the position of the paper sensor 152 is moved and adjusted. For example, when a detection hole indicating the label attachment position is formed at the center of a newly loaded paper (label paper), the paper sensor 152 is moved and adjusted according to the position through which the detection hole passes.
At this time, the paper sensor 311 attached to the head unit 200 also needs to be moved and adjusted to a position facing the paper sensor 152 on the printer main body 100 side.
[0041]
In the printer according to the present embodiment, as described above, the sensor unit 300 in the open position is detached from the head unit 200 and can be freely rotated. Therefore, when the paper is replaced, only the sensor unit 300 is rotated to the closed position. (See FIG. 4). In the closed position, the second engagement portion 321 b engages with the second locking claw 132. As a result, the sheet can be pressed, so that even a sheet with winding or the like can be easily and appropriately placed on the sheet conveyance path. Then, the paper sensor 311 can be moved and adjusted by manual operation so as to face the paper sensor 152 on the printer main body 100 side.
[0042]
When the head unit 200 in the open position is rotated to the closed position, the first locking claw 222 engages with the first engagement portion 321a, and the sensor unit 300 and the head unit 200 are connected again (FIG. 1). reference).
[0043]
Next, the structure of the head support plate will be described.
10A and 10B are diagrams showing the configuration of the head support plate. FIG. 10A is a front view, FIG. 10B is a rear view, and FIG. 10C is a side view.
The head support plate 210 is formed of an aluminum alloy plate material, and a line-shaped print head 201 is mounted in the width direction along the front end edge 210a. Further, a notch 211 formed in the center is provided with a wiring connector 212 and is electrically connected to the print head 201. The upper surface of the head support plate 210 is entirely covered with an insulating sheet 213 except for the heat sensitive part of the print head 201.
[0044]
Here, a protrusion 214 having a semicircular cross section is formed along the print head 201 on the leading edge 210a of the head support plate 210 as shown in an enlarged view in FIG. In the label printer, the label paper mounted on the paper transport path may be moved (returned) in the direction opposite to the paper discharge direction in order to adjust the printing position. At this time, the edge of the label may be caught by the edge of the print head 201 and peeled off from the mount. Therefore, in this embodiment, a protrusion 214 having a semicircular cross section is formed along the print head 201 at the leading edge 210 a of the head support plate 210, and the edge of the label that returns is formed by the protrusion 214. By lifting, the inconvenience that the edge of the label contacts the edge of the print head 201 is avoided.
[0045]
The protrusion 214 can be easily formed by half-pressing the tip edge 210a portion of the head support plate 210 made of an aluminum alloy plate from the back surface side.
[0046]
The head support plate 210 having the above-described configuration is provided with positioning projections 215 and 215 on the back surface, and further provided with fastening holes 216 such as screw holes. On the other hand, the head support member 240 is built in the head unit 200 as shown in FIG. A fastening hole 241 such as a screw hole is provided on the surface of the head support member 240 at a position corresponding to the fastening hole 216 of the head support plate 210. The head support member 240 has elongated holes 242 and 242 at positions corresponding to the positioning protrusions 215 and 215 of the head support plate 210.
[0047]
The head support plate 210 has the positioning protrusions 215 and 215 aligned with the long holes 242 and 242 of the head support member 240, and a fastener such as a screw is fitted into the fastening holes 216 and 241 from the front side, It can be mounted on the surface of the support plate 210. The operation can be easily performed from the lower surface side of the head unit 200.
[0048]
As shown in FIG. 12A, a front / rear tilt adjustment mechanism 250 for the head support plate 210 is provided on the inner bottom portion of the head unit 200.
The head support member 240 on which the head support plate 210 is mounted on the surface has mounting holes 240a and 240a formed at two locations on the front edge as shown in FIG. The head unit 200 is attached by engaging with the hook-shaped support portions 203, 203 provided on the head unit 200. In this mounting structure, the head support member 240 is rotatable and can also be moved moderately in the vertical direction.
The lock pin 230 described above extends from one side surface of the head member 24, and a pin having the same shape extends from a symmetrical position on the other side surface. Each of these pins engages with both side walls of the head unit 200 to constitute a pivot point of the head support member.
[0049]
Then, the engagement piece 243 extending from the central portion of the rear end edge is moved and adjusted in the vertical direction by the front / rear inclination adjusting mechanism 250, whereby the head support plate 210 attached to the head support member 240 is supported by the front end edge. It rotates around the parts 203 and 203 and is held in a horizontal posture or an arbitrary inclined posture. By this forward / backward tilt adjustment, the contact position of the print head 201 with respect to the paper slightly changes back and forth. An appropriate printing operation can be realized by appropriately executing this adjustment according to the rigidity of the paper. For example, for thin paper with low rigidity, the optimum print point is located almost directly above the center of the platen 110, while for thick paper with high rigidity, the optimum print point is located on the paper discharge side from the center of the platen 110. To do.
That is, the forward / backward tilt adjustment mechanism 250 constitutes a contact position adjustment unit of the print head 201 with respect to the paper.
[0050]
The forward / backward tilt adjustment mechanism 250 includes a support member 251 shown in FIG. 13A, an operation member 252 shown in FIGS. 13B and 13C, and a cam follower 253 shown in FIG. 2B shows one end surface of the operation member 252 and FIG. 2C shows the other end surface of the operation member 252.
[0051]
The operation member 252 is formed in a disk shape and has a mounting hole 254 at the center thereof. Further, as shown in FIG. 13B, a cam 255 made of a circumferential groove whose distance from the center changes stepwise is formed on one end face of the operation member 252. Further, a scale 256 indicating the operation position of the operation member 252 is engraved on one end surface of the operation member 252 in the circumferential direction. On the other hand, a plurality of recesses 257 are formed on the other end surface of the operation member 252 at intervals in the circumferential direction as shown in FIG.
[0052]
As shown in FIG. 13 (d), the cam follower 253 has a mounting hole 258 formed at a substantially central position, and arc-shaped cutout holes 259 and 259 formed at two places around the mounting hole 258. Further, the tip portion 253a of the cam follower 253 is thin and elastically bent, and a protrusion 260 that engages with the cam 255 is formed at the tip. On the other hand, a notch groove 261 that engages with the engagement piece 243 of the head support member 240 is formed at the base end of the cam follower 253.
[0053]
As shown in FIG. 13A, two support shafts 262 and 263 are formed on the front surface of the support member 251, and a convex portion 264 is formed around one support shaft 262. is there.
As shown in FIG. 14, the operating member 252 is rotatably mounted on one of the support shafts 263 so as to fit the mounting hole 254. Here, the operation member 252 is mounted on the support member 251 with the cam 255 forming surface on the front surface side and the recess 257 forming surface on the back surface side (that is, the side in contact with the front surface of the support member 251). At this time, the concave portion 257 of the operation member 252 is disposed at a position that can be freely engaged with and disengaged from the convex portion 264 formed on the support member 251.
[0054]
Further, the cam follower 253 is swingably mounted on the other support shaft 263 formed on the front surface of the support member 251 so as to fit the mounting hole 258. At this time, the protrusion 260 formed at one end of the cam follower 253 is engaged with the cam 255 formed of a circumferential groove. The distal end portion 253a of the cam follower 253 contacts the surface of the operation member 252 (formation surface of the cam 255) and elastically holds the surface (see FIG. 14). As a result, the distal end portion 253a can press the operation member 252 and generate a click feeling on the operation member 252.
[0055]
On the front surface of the support member 251, flanges 265, 265 are formed to project at positions corresponding to the cutout holes 259, 259 of the cam follower 253. , 259 engage with each other, and the cam follower 253 is prevented from falling off from the support member 251. The cutout holes 259 and 259 are set to have a vertical dimension that allows the cam follower 253 to swing.
[0056]
The engagement piece 243 of the head support member 240 is engaged with the notch groove 261 formed at the other end of the cam follower 253.
As described above, the forward / backward tilt adjusting mechanism 250 formed by assembling each component can be mounted on the inner bottom portion of the head unit 200 as a single unit, and therefore the mounting operation is easy.
[0057]
As shown in FIG. 17A, a cutout window 204 is formed at a predetermined position on the side wall of the head unit 200, and a part of the operation member 252 is exposed from the cutout window 204. A scale 256 engraved on the exposed portion is configured so as to be visible from the outside. The operator can adjust the inclination of the head support plate 210 in the front-rear direction by rotating the operation member 252 using the scale 256 as a guide.
[0058]
The forward / backward tilt adjustment mechanism 250 attached to the head unit operates as follows. That is, when the operation member 252 is rotated, the projection 260 moves in the vertical direction along the cam 255 and the cam follower 253 swings around the support shaft 263. The head support member 240 with which the engagement piece 243 engages with the notch groove 261 of the cam follower 253 rotates around the lock pin 230 in conjunction with the cam follower 253. Here, the cam follower 253 and the cam 255 function as an adjustment mechanism for adjusting the contact position of the print head 201 with respect to the paper inserted between the platen 110 and the print head 201.
As a result of adjusting the forward / backward inclination of the head support plate 210 by the forward / backward inclination adjustment mechanism 250, the print head can be adjusted to the optimum print point of the contact position.
[0059]
Furthermore, at the discontinuous operation position of the operation member 252, any of the recesses 257 formed in the operation member 252 engages with the protrusions 264 of the support member 251 with a click feeling. Thereby, the operation position is held, and the unintended rotation of the operation member 252 is prevented. That is, the concave portion 257 and the convex portion 264 constitute an operation position holding unit that holds the operation member 252 at a discontinuous operation position with a click feeling.
In addition, as a result of being able to rotate the support member 251 with a click feeling, the operation of aligning the scale 256 can be easily performed, and adjustment can be performed with a certain reproducibility even if the operator changes.
[0060]
Next, as shown in FIG. 12, a pressure center point moving mechanism 270 of the print head 201 is provided at the inner bottom of the head unit 200.
As described above, the front end edge portion of the head support member 240 attached to the support portions 203 and 203 of the head unit 200 is allowed to move in the vertical direction within a certain range (see FIG. 12B). . The head support member 240 is pressed and urged downward from two locations on the back side by urging members 271 and 272 such as coil springs, and maintains a constant posture by the urging force.
Here, one urging member 271 is held at the inner bottom of the head unit 200, and the other urging member 272 is supported by the cam follower 273 of the pressure center point moving mechanism 270.
[0061]
The pressure center point moving mechanism 270 includes a cam follower 273 shown in FIG. 15A and an operation member 274 shown in FIGS. FIG. 4C shows one end surface of the operation member 274, and FIG. 4D shows the other end surface of the operation member 274.
The operation member 274 is formed in a disc shape and has a mounting hole 275 at the center thereof. As shown in FIG. 16, the operation member 274 is rotatably mounted on a support shaft 205 that protrudes from the inner bottom surface of the head unit 200.
[0062]
A cylindrical portion that forms a cam 276 protrudes from one end surface of the operation member 274 (see FIGS. 15B and 16). The tip surface of the cylindrical portion is a spiral inclined surface. This inclined surface constitutes a cam surface 276a. Further, a scale 277 indicating the operation position is engraved on the other end surface of the operation member 274 (see FIG. 15D).
[0063]
As shown in FIGS. 15B and 16, a recess 278 is formed at a discontinuous position on the cam surface 276 a, and a protrusion of a cam follower 273 described later at a discontinuous operation position of the operation member 274. 279 engages with the recess 278 with a click. As a result, the operation position is maintained, and the unintended operation member 274 is prevented from rotating. That is, the concave portion 278 and the convex portion 279 constitute an operation position holding unit that holds the operation member 274 at a discontinuous operation position with a click feeling.
In addition, as a result of being able to rotate the support member 274 with a click feeling, the operation of aligning the scale 277 can be easily performed, and adjustment can be performed with a certain reproducibility even if the operator changes.
[0064]
The cam follower 273 has a projection 279 formed at the tip, and the projection 279 engages with the cam surface 276a of the operation member 274 as described above. In addition, the cam follower 273 constitutes a swing fulcrum with the base end corner portion 273 a in contact with the inner bottom portion of the head unit 200.
[0065]
A concave portion 280 that supports the biasing member 272 is formed in the central portion of the cam follower 273, and a notch hole 281 is formed in the inner bottom portion thereof. A support pin 206 protrudes from the inner bottom portion of the head unit 200 so as to correspond to the notch hole 281. When the cam follower 273 is mounted on the inner bottom portion of the head unit 200, the support pin 206 has the notch hole 281. It penetrates and is disposed in the recess 280. One end of the urging member 272 is disposed in the recess 280 of the cam follower 273 while being supported by the support pin 206. The other end of the urging member 272 is in contact with the head support member 240.
[0066]
The cam follower 273 also has a notch hole 282 formed in the vicinity of the base end. The cam follower 273 protrudes from the inner bottom portion of the head unit 200 when the cam follower 273 is mounted on the inner bottom portion of the head unit 200. The positioning pin 207 is engaged. The positioning pin 207 holds the cam follower 273 at a fixed position of the head unit 200.
[0067]
Further, as shown in an enlarged view in FIG. 12C, a holding pin 208 protrudes from the inner wall of the head unit 200. On the other hand, one side surface of the cam follower 273 faces the holding pin 208. A contact portion 283 is formed to extend at a position. The contact portion 283 and the holding pin 208 constitute a means for preventing the cam follower 273 from falling off. When the cam follower 273 attempts to come out of the positioning pin 207, the contact portion 283 contacts the holding pin 208 and the cam follower 273. Prevents falling off.
[0068]
That is, in the mounted state shown in FIG. 16, the cam follower 273 is pressed and held on the inner bottom side of the head unit 200 by the urging member 272. However, when the cam follower 273 is attached to the head unit 200 or when the head support member 240 is removed from the head unit 200 for maintenance, the holding state may be released and the cam follower 273 may fall off. Such unintentional dropping is prevented by the contact portion 283 coming into contact with the holding pin 208, and good workability is ensured.
[0069]
As shown in FIG. 17B, a notch window 209 is formed at a predetermined position of the head unit 200, and a part of the operation member 274 is exposed from the notch window 209, and is exposed from the notch window 209. The scale 277 carved in the portion to be formed is configured to be visible from the outside. The operator can adjust the urging force of the urging member 272 by rotating the operation member 274 using the scale 277 as a guide.
[0070]
The pressure center point moving mechanism 270 attached to the head unit 200 operates as follows. That is, when the operation member 274 is rotated, the convex portion 279 of the cam follower 273 moves in the vertical direction along the cam surface 276a, and the cam follower 273 swings around the swing fulcrum of the base end corner portion 273a. With this operation, the compression state of the urging member 272 disposed between the cam follower 273 and the head support member 240 changes, and the urging force acting on the head support member 240 changes.
[0071]
The print head 201 is preferably in contact with the paper with uniform pressure. For this purpose, the pressure center point of the print head 201 must be at the center of the paper. Therefore, by adjusting the urging force of the urging member 272, the pressure center of the print head 201 is moved to the vicinity of the center of the sheet so that the print head 201 contacts the sheet with uniform pressure.
As described above, the cam 276, the cam follower 273, and the biasing member 272 constitute a mechanism for adjusting the contact pressure acting state of the print head 201 with respect to the sheet, and the pressure center point moving mechanism 270 is a contact pressure acting state adjustment. Parts.
[0072]
The front / rear tilt adjustment mechanism 250 and the pressure center point moving mechanism 270 described above are disposed on one side at the inner bottom of the head unit 200, and the operation members 252 and 274 are both exposed from one side of the head unit 200. Since it can be operated on the same side, the operability is good and the adjustment work can be easily performed.
[0073]
Returning to FIG. 4, the cable guide 290 is attached to the head unit 200 along with the head support member 240, and a notch hole 291 is formed at the bottom side end of the cable guide 290. The printer main body 100 is provided with a cable guide hole 160 at a portion facing the notch hole 291 when the head unit 200 is in the closed position. The cable guide hole 160 is provided inside the rotation axis of the head unit 200. As a result, the electric cable 400 does not come out of the printer main body 100, and the apparatus can be miniaturized.
The electric cable 400 connected to the print head 201 is guided from the cable guide 290 through the notch hole 291 to the cable guide hole 160 and connected to the circuit board in the printer main body 100.
[0074]
In addition, this invention is not limited to embodiment mentioned above, Of course, various deformation | transformation or application implementation is possible.
For example, as shown in FIG. 18, a pair of pressure center point moving mechanisms 270 that are adjustment mechanisms for adjusting the contact pressure acting state of the print head 201 are provided at symmetrical positions in the width direction with the center of the head unit 200 as a boundary. If each of the pressure center point moving mechanisms 277 and 277 supports the urging members 271 and 272, the operation of each of the mechanisms 277 and 277 adjusts the pressure center point of the print head 201 with respect to the paper, The contact pressure of the print head 201 can also be adjusted. In this case, the pressure center point moving mechanisms 277 and 277 function as a pressure center point moving-contact pressure adjusting mechanism.
[0075]
Further, as shown in FIG. 19, if a biasing member 272 is arranged at the center in the width direction of the head unit 200 and the biasing member 272 is supported by a mechanism similar to the pressure center point moving mechanism 277, The contact pressure of the print head 201 with respect to the paper can be adjusted by operating the mechanism 277. In this case, the mechanism 277 functions as a contact pressure adjusting mechanism.
[0076]
【The invention's effect】
As described above, according to the present invention, the contact pressure acting state or the contact position of the print head can be adjusted with respect to the paper inserted between the platen and the print head, and the adjusted state can be reliably ensured. Thus, a highly accurate printing operation can be stably performed over a long period of time.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an external appearance of a printer according to an embodiment of the present invention, showing a state where a head unit is in a closed position.
FIG. 2 is a perspective view showing an external appearance of a printer according to an embodiment of the present invention, showing a state where the head unit is opened halfway.
FIG. 3 is a perspective view showing an external appearance of a printer according to an embodiment of the present invention, showing a state where a head unit is in an open position.
FIG. 4 is a perspective view showing an appearance of a printer according to an embodiment of the present invention, and shows a state where a sensor unit is closed.
5A and 5B are diagrams showing a platen, in which FIG. 5A is a partially cutaway front view, and FIG. 5B is a right side view.
6A is an enlarged front view showing a bearing member attached to one end of the platen, and FIG. 6B is a side view showing a platen support portion formed at one end of the printer main body.
7A is an enlarged front view showing a bearing member attached to the other end of the platen, FIG. 7B is a right side view of the same, and FIG. 7C is formed at the other end of the printer main body. The side view which shows a platen support part, (d) is front sectional drawing of the platen support part.
FIGS. 8A and 8B are diagrams showing a braking means including a braking protrusion and a braking plate, where FIG. 8A is a front view and FIG. 8B is a side view.
FIG. 9 is a perspective view showing an engagement / disengagement relationship between a first locking member provided in the head unit and a second locking member provided in the printer main body, and first and second engaging portions formed in the sensor unit. FIG.
10A is a front view, FIG. 10B is a front view, FIG. 10B is a rear view, FIG. 10C is a side view, and FIG. is there.
FIG. 11 is a perspective view showing a mounting structure of a head support plate.
12A is a bottom view showing a longitudinal tilt adjusting mechanism and a pressure center point moving mechanism provided on the inner bottom portion of the head unit, and FIG. 12B is a cross-sectional side view showing an enlarged support portion of the head support member; (C) is an enlarged bottom view showing a cam follower drop-off prevention mechanism which is a component of the pressure center point moving mechanism.
13A is a front view of a support member that constitutes a front-rear tilt adjustment mechanism, FIG. 13B is a front view of an operation member that constitutes a front-rear tilt adjustment mechanism, and FIG. 13C is a rear view of the operation member. d) is a front view of a cam follower constituting a longitudinal tilt adjusting mechanism.
FIG. 14 is a front view of the longitudinal tilt adjusting mechanism.
15A is a bottom view of a cam follower constituting the pressure center point moving mechanism, FIG. 15B is a perspective view of an operating member constituting the pressure center point moving mechanism, and FIG. 15C is a front view of the operating member. (D) is the back view of an operation member similarly.
FIG. 16 is a partial cross-sectional front view of the pressure center point moving mechanism.
17A is a perspective view of a notch window that partially exposes the operation member of the forward / backward tilt adjustment mechanism, and FIG. 17B is a plan view of the notch window that partially exposes the operation member of the pressure center point moving mechanism. .
FIG. 18 is a bottom view showing an application example of a pressure center point moving mechanism.
FIG. 19 is a bottom view showing an application example in which the pressure center point moving mechanism functions as a contact pressure adjusting mechanism.
[Explanation of symbols]
100: printer main body 101: support shaft 102: braking plate 102a: protrusion 110: platen 111: elastic member 112: rotating shaft 113, 114: bearing member 115: main body portion 116: mounting blade portion 117: platen support portion 117a: notch Groove 118: Body 119: Mounting wing 119a: Outer wall 119b: Inner wall 119c: Upper wall 120: Locking piece 120a: Engaging protrusion 121: Platen support 121a: Notch groove 121b: Engaging groove 130: Second Locking member 131: Second recess 132: Second locking claw 140: Locking member 150: Guide bar 151: Paper guide 152: Paper sensor 160: Cable guide hole 200: Head unit 201: Print head 202: Brake protrusion 203: Support portion 204: Notch window 206: Support pin 207: Positioning pin 208: Holding pin 209: Notch window 210: Support plate 210a: tip edge 211: notch 212: connector 213: insulating sheet 214: protrusion 215: protrusion 216: fastening hole 220: first locking member 221: first recess 222: first locking claw 230 : Lock pin 240: Head support member 240 a: Mounting hole 241: Fastening hole 242: Long hole 243: Engagement piece 250: Front / rear tilt adjustment mechanism 251: Support member 252: Operation member 253: Cam follower 254: Mounting hole 255: Cam 256 : Scale 257: Recess 258: Mounting hole 259: Notch hole 260: Protrusion 261: Notch groove 262, 263: Support shaft 264: Convex part 270: Pressure center point moving mechanism 271, 272: Biasing member 273: Cam follower 274: Operation Member 275: Mounting hole 276: Cam 276a: Cam surface 277: Scale 278: Concave part 279: Convex part 280: Concave part 281, 2 2: Notch hole 283: Contact portion 290: Cable guide 291: Notch hole 300: Sensor unit 300a: Base end 311: Paper sensor 320: Bar-shaped portion 321: Projection 321a: First engagement portion 321b: Second engagement Part 400: Electric cable

Claims (10)

An adjustment mechanism for adjusting a contact pressure acting state or a contact position of the print head with respect to a sheet inserted between the platen and the print head, an operation member for operating the adjustment mechanism, and the operation member. An operation position holding means for holding a click feeling at discontinuous operation positions. The adjustment mechanism is engaged with a spring member that urges the print head toward the platen, a cam operated by the operation member, and a cam surface formed on the cam, and is interlocked with the operation of the cam. The printer according to claim 1, further comprising: a cam follower that expands and contracts the spring member to change a contact pressure acting state of the print head on the paper. The operating member is formed in a disc shape, and a cylindrical portion extends coaxially from one end surface thereof, and a tip surface of the cylindrical portion is formed as an inclined surface,
3. The printer according to claim 2, wherein the cam is configured by the cylindrical portion, and the inclined surface is configured as a cam surface. 3. A plurality of concave portions are formed on the cam surface, and convex portions detachable from the concave portions are formed on the cam follower, and the operation position holding means is configured by the concave portions and the convex portions. Or 3 printers. The adjustment mechanism includes a cam operated by the operation member, a cam follower that engages with a cam surface formed on the cam, and changes a contact position of the print head with respect to the paper in conjunction with the operation of the cam. The printer according to claim 1, further comprising: 6. The printer according to claim 5, wherein the operation member is formed in a disc shape, and a circumferential groove is formed on one end surface thereof, and the cam is constituted by the circumferential groove. The operation member is rotatably supported and includes a support member that swingably supports the cam follower, and the operation member and the cam follower are assembled to the support member to constitute one unit. The printer according to claim 6. The other end surface of the operation member or one of the support members is formed with a plurality of concave portions at intervals in the circumferential direction, and the other is formed with a convex portion that is detachable from the concave portion. 8. The printer according to claim 7, wherein the operation position holding means is configured as described above. In a printer comprising a printer body with a platen attached and a head unit with a print head attached,
The head unit is
An adjustment mechanism for adjusting the contact pressure acting state of the print head with respect to the paper inserted between the platen and the print head, an operation member for operating the adjustment mechanism, and the operation member are not used. An operation position holding means for holding a click feeling at continuous operation positions, and a contact pressure acting state adjusting unit,
An adjustment mechanism for adjusting the contact position of the print head with respect to a sheet inserted between the platen and the print head, an operation member for operating the adjustment mechanism, and the operation member are discontinuous. An operation position holding means that holds the operation position with a click feeling, and a contact position adjustment unit,
A printer comprising: While making the head unit into a box shape,
The printer according to claim 9, wherein the operation member of the contact pressure acting state adjustment unit and the operation member of the contact position adjustment unit are arranged to be operated from one side surface of the head unit.

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