JP4580088B2 - Line thermal printer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a line thermal printer having a platen and a line thermal head.
[0002]
[Prior art]
Conventionally, in a line thermal printer that performs printing by bringing a platen and a line thermal head close to each other, it is necessary to appropriately bring the platen and the line thermal head close to each other in order to perform printing accurately. In addition, the platen and the line thermal head have been separated from each other for paper replenishment and jam processing.
[0003]
For this reason, when performing printing, a mechanism for holding the platen and the line thermal head in an appropriate positional relationship, a mechanism for separating the platen and the line thermal head from each other, and the like are necessary.
[0004]
[Problems to be solved by the invention]
An object of the present invention is to provide a line thermal printer having a mechanism for accurately positioning a platen and a line thermal head.
[0005]
[Means for Solving the Problems]
In order to solve the above problems, a printer of the present invention has a main body frame having a line thermal head, a lock member, and an elastic member, and a cover frame having a platen, and the line thermal head has a printing position close to the platen. The cover frame is configured to be movable between the mounting position that moves the platen close to the line thermal head and the non-mounted position that retracts the platen from the line thermal head. The member is configured to be movable between a lock position for holding the cover frame at the mounting position and a release position for releasing the holding, and the elastic member biases the line thermal head to the print position side and moves the lock member to the lock position side. It is characterized by energizing. The urging of the lock member for holding the cover frame and the urging of the line thermal head to the platen side are performed by one elastic member.
[0006]
The lock member preferably moves between the lock position and the release position in conjunction with the movement of the line thermal head between the print position and the non-print position.
Further, the lock member preferably has a bearing portion that rotatably supports the line thermal head.
[0007]
Furthermore, the lock member preferably has a holding portion that holds the cover frame in the mounting position.
Further, the cover frame has a pressing member, and when the locking member is located at the locking position, the pressing member presses the locking member toward the release position, thereby enabling the cover frame to be moved to the mounting position. Is preferred.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
The printer according to the present invention will be described below.
FIG. 1 is a schematic central sectional view of a printer according to the present invention. Here, 1 is a thermal roll, and 2 is a shaft of the thermal roll 1. 3 (described with a two-dot chain line) indicates a state in which the thermal paper P is used and the diameter of the roll is reduced. Reference numeral 10 denotes a base, 20 denotes a platen cover, and 30 denotes a cutter unit.
[0009]
The base 10 is provided with a first holding member 11, a bearing member 13, a guide member 14, and a plate holding member 15. The first holding member 11 holds the cover frame 20 rotatably about the shaft 12. Further, the bearing member 13 holds the shaft 2 of the thermal roll 1 in a rotatable manner.
The guide member 14 has a function of always transporting the thermal paper P fed from the thermal roll 1 toward the later-described line thermal head 43 at a substantially constant height. When the diameter of the thermal roll 1 is reduced, the position where the thermal paper P is fed out changes. Therefore, the guide member 14 functions so as to be always conveyed from the same height in the direction of the line thermal head 43 by bending the conveyance direction of the thermal paper P. Therefore, it is preferable that the height of the guide member 14 is equal to or higher than the position of the lowest point of the central axis 2 of the thermal roll paper 1.
[0010]
The cover frame 20 includes a regulating member 21, a platen roller 22, a platen roller shaft 23, a first engagement member 24, a fixed blade 25, a dome-shaped plate member 26, and the like.
The cutter unit 30 includes a movable blade 31, a second engagement member 32, a swing support member 33, a protrusion 34, a stopper 35, and the like.
[0011]
The plate 40 is fixed on the plate holding member 15, and a guide plate 41, a sensor 42, a line thermal head 43, an elastic member 44, a second holding member 45, and the like are provided above the plate 40. The second holding member 45 is provided with a groove 46 and a third engagement member 47. Therefore, the swing support member 33 of the cutter unit 30 is inserted into a groove 46 provided in the second holding member 45, and the cutter unit 30 swings up and down with the swing support member 33 as a fulcrum as a whole. It is held by the holding member 45 as possible.
[0012]
The sensor 42 is attached below the guide plate 41 in order to detect the presence or absence of the thermal paper P. Further, as the sensor 42, a reflection type sensor composed of a light emitting element and a light receiving element is used. When the thermal paper P is not detected at the position of the sensor 42, a no-paper signal is transmitted from the sensor 42 to a control circuit (not shown). In the reflection type sensor, the light from the light emitting element is emitted toward the conveyance path, and the light reflected from the paper is incident on the light receiving element, thereby detecting the presence or absence of the paper. Therefore, in particular, in the reflective sensor, it is preferable that the distance between the sensor and the paper is substantially constant. In the present embodiment, a reflective sensor is used, but other types of sensors can also be used.
[0013]
Reference numeral 50 denotes an elastic member (a helical spring) provided between the projection 34 of the cutter unit 30 and the second holding member 45, and an urging force for rotating the cutter unit 30 in the clockwise direction in FIG. Is always given to the cutter unit 30.
Hereinafter, the base 10 and the plate 40, and various members provided on the base 10 and the plate 40 are collectively referred to as a main body frame. In FIG. 1, the platen roller shaft 23 is held on the main body frame by a lock member 60 described later, whereby the cover frame 20 is maintained in the state shown in FIG. 1. It is in position. Furthermore, the state in which the holding of the platen roller shaft 23 is released, for example, the state of FIG. 2 is referred to as the cover frame being in the retracted position.
[0014]
In response to the cover frame 20 being held in the state of FIG. 1, the first engagement member 24 of the cover frame 20 is engaged with the second engagement member 32 of the cutter unit 30, and the cutter unit 30 is moved counterclockwise. The cutter unit 30 is held at the position shown in FIG. 1 while being pressed around and opposed to the urging force of the elastic member 50. Further, at this time, the projecting portions 31 a and 31 b of the movable blade 31 of the cutter unit 30 press the fixed blade 25 on the cover frame 20 side from the top to the bottom in the drawing, whereby the movable blade is placed on the fixed blade 25. The both side protrusions 31a and 31b of 31 are positioned so as to contact each other. From the state of FIG. 1, the movable blade 31 is moved by sliding on the fixed blade 25 to the cover frame 20 side by a drive mechanism (not shown) so that the thermal paper P can be cut. Yes.
[0015]
Elastic member 44 is biased toward the line thermal head 43 to the platen roller 22 side direction, and is configured so as to sandwich the thermal paper P by the platen roller 22 and the line thermal head 43. When the platen roller 22 rotates in the state of FIG. 1, the thermal paper P is unwound from the thermal roll 1 and conveyed upward in the drawing.
[0016]
The line thermal head 43 is provided with a plurality of heating elements in a row in the longitudinal direction of the platen roller 22 , and the heating elements generate heat by a drive circuit (not shown), whereby printing or the like is performed on the thermal paper P. It is comprised so that. Therefore, as the platen roller 22 rotates, printing is performed on the thermal paper P while the thermal paper P is being conveyed, and is discharged outside the printer. In the present embodiment, the platen is configured in a roller shape. However, the platen is not limited to the roller shape as long as the positional relationship between the print head and the sheet can be regulated. It is also possible to use a shape. Further, when a roller-shaped platen is not used, a separate transport mechanism for transporting paper is required.
[0017]
FIG. 2 shows a case where the cover frame 20 is in the retracted position. The state of FIG. 2 shows a state where the holding of the platen roller shaft 23 is released. In the state of FIG. 2, since the first engagement member 24 of the cover frame 20 is engaged with the second engagement member of the cutter unit 30 and does not press the cutter unit 30, the cutter unit 30 has an elastic member 50. Thus, an urging force is applied so as to rotate in the clockwise direction in the figure with the swing support member 33 as a fulcrum. However, the stopper 35 of the cutter unit 30 is configured not to rotate in the clockwise direction beyond the position of FIG. 2 by engaging with the third engaging member 47 provided on the frame 40. In FIG. 2, the line thermal head 43 is held at a position retracted from the platen roller 22 side against the urging force of the elastic member 44 by a lock member 60 (not shown).
[0018]
FIG. 3 is a top view of the state of FIG. 1 viewed from above in FIG. In FIG. 3, 24 a and 24 b are projecting portions on both sides of the first engaging member 24 provided on the cover frame 20. Reference numeral 27 denotes a gear provided on the platen roller shaft 23. Further, 48 is a gear provided on the plate 40. The gear 48 receives a driving force from a motor (not shown), engages with the gear 27, and rotates the platen roller shaft 23 . Reference numeral 60 denotes a lock member for holding the cover frame 20 at the position shown in FIG. As can be understood from FIG. 3, the thermal paper P passes between the cover frame 20 and the cutter unit 30 and between both side protrusions 24 a and 24 b of the first engagement member 24.
[0019]
4 is a top view of the state of FIG. 2 viewed from above in FIG. In FIG. 4, 31 a and 31 b are projecting portions on both sides of the movable blade 31. Moreover, 32a and 32b have shown the both-ends tip part of the 2nd engagement member. FIG. 4 shows a state where the stopper 35 of the cutter unit 30 and the third engagement member 47 provided on the plate 40 are engaged.
[0020]
FIG. 5 is a view showing the front end portion of the cover frame 20. Reference numeral 28 denotes an opening provided in the regulating member 21. The opening 28 is provided corresponding to the position where the sensor 42 is provided. Reference numerals 203 and 205 denote bearing portions that rotatably support the platen roller shaft 23. Reference numerals 201 and 204 denote sheet metal frame pairs provided with bearing portions 203 and 205. Reference numeral 202 denotes a pressing portion provided on the sheet metal frame 201.
[0021]
The regulating member 21 is disposed upstream of the platen roller 22 in the conveyance direction of the thermal paper P, and has a width capable of regulating the thermal paper P over almost the entire width of the thermal paper P. The distance between P and the sensor 42 is kept substantially constant, and a malfunction of detection of the sensor 42 is prevented. The restricting member has a substantially flat portion, and is arranged so that the flat portion faces the sensor 42. Further, the opening 28 is provided almost directly above the sensor 42 in a state where the cover frame 20 in FIG. 1 is in the printing position, and the light from the light emitting element of the sensor 42 is reflected on the regulating plate 21, and heat sensitive. Although there is no paper P, it is prevented that the thermal paper P is misidentified. In this embodiment, the regulating member is provided over almost the entire width of the thermal paper P. However, if the distance between the thermal paper P and the sensor 42 can be maintained substantially constant in the vicinity of the sensor 42, the regulating member is not necessarily provided. It is not necessary to provide a regulating member over the entire width of the thermal paper P.
[0022]
As described above, the thermal paper P is fed out from the thermal roller 1, the conveyance direction is slightly bent by the guide member 14, and then conveyed while contacting the substantially flat portion of the lower end portion of the regulating member 21 of the cover frame 20. Then, while being sandwiched between the platen roller 22 and the line thermal head 43, it is discharged upward in FIG.
[0023]
Hereinafter, the mutual relationship among the line thermal head 43, the elastic member 44, and the lock member 60 will be described in detail. FIG. 10 is a perspective view showing the relationship between the line thermal head 43, the elastic member 44, and the lock member 60. In FIG. 10, reference numerals 401 and 411 denote side walls, which are fixed to the plate 40. The elastic member 44 composed of a spring or the like urges the line thermal head 43 toward the platen roller 22.
[0024]
A square columnar shaft 73 is provided at the end of the line thermal head 43 on the near side in the figure, and the shaft 73 is fitted in a cylindrical spacer 70. Further, the cylindrical spacer 70 is provided with protrusions 71 and 72. Furthermore, the spacer 70 is configured to be inserted into the bearing portion e of the lock member 60 through the opening 405 of the side wall 401. A square columnar shaft is also provided at the other end of the line thermal head 43, and the shaft is fitted into the claw member 80.
[0025]
FIG. 11 shows the shape of the lock member 60. FIG. 11A shows the front surface of the lock member 60, and FIG. 11B shows the back surface of the lock member 60. a is a first cam portion, b is a claw portion, c is a second cam portion, d is a handle portion, e is a bearing portion, f is a third cam portion, and g is a fourth cam portion. The bearing portion e is provided with protrusions corresponding to the protrusions 71 and 72 of the spacer 70 so that the spacer 70 once inserted into the lock member 60 is not easily removed. The spacer 70 is rotatably inserted into the bearing portion e.
[0026]
FIG. 6 shows the position and the like of the lock member 60 when the cover frame 20 is in the mounting position shown in FIGS. 1 and 3. Since the line thermal head 43 is urged toward the platen roller 22 by the elastic member 44 as shown in FIG. 10, the lock member 60 is connected to the lock member 60 via the shaft 73 and the spacer 70 of the line thermal head in FIG. Directional force is working. Accordingly, the claw portion b of the lock member 60 presses the platen roller shaft 23 against the U-shaped groove 402 of the side wall 401 and holds the platen roller shaft 23 so as not to easily come out of the U-shaped groove 402. By holding the platen roller shaft 23, the cover frame 20 is held at the mounting position. In FIG. 6, the third cam portion f of the lock member 60 is engaged with the protrusion 403 fixed to the side wall 401 so that the lock member 60 does not rotate further in the direction of the arrow A. . The state in which the lock member 60 presses the platen roller shaft 23 against the U-shaped groove 402 is referred to as the lock member 60 being in the lock position. Furthermore, the lock member 60 is in the release position when the lock member does not press the platen roller shaft 23 against the U-shaped groove.
[0027]
A case of releasing the holding of the platen roller shaft 23 by the lock member 60 will be described with reference to FIGS. 7 and 8. When the holding by the lock member 60 is released, the handle d of the lock member is rotated in the direction of arrow B in FIG. 7 against the urging force of the elastic member 44. When the lock member 60 is rotated in the direction of arrow B, the engagement between the third cam portion f of the lock member 60 and the projection 403 is released, and the fourth cam portion g attempts to get over the projection 403 (see FIG. 7). When the lock member 60 is further rotated in the direction of arrow B, the fourth cam portion g completely gets over the projection 403, the second cam portion c engages with the projection 404, and beyond that, the lock member 60 moves to the arrow. It is configured not to rotate in the direction B (see FIG. 8). In addition, once the fourth cam portion g completely gets over the protrusion 403, it does not easily rotate in the reverse direction, so that the lock member 60 is held in that state.
[0028]
When the lock member 60 moves from the position of FIG. 6 to the position of FIG. 8 and is held in that state, the spacer 70 inserted into the bearing portion e of the lock member 60 also moves in the opening 405 in the direction of arrow B. Accordingly, the line thermal head 43 is also moved in the direction of retreating from the platen roller 22 against the urging force of the elastic member 44. When the lock member 60 is in the state of FIG. 8, the line thermal head 43 is held in a state of being retracted from the platen roller 23 as shown in FIG. This state is said that the line thermal head 43 is in the non-printing position. Conversely, a state where the elastic member 44 is biased toward the platen roller 23 means that the line thermal head 43 is at the printing position.
[0029]
When the claw portion b of the lock member 60 releases the holding of the platen roller shaft 23, the cover frame 20 can freely move from the mounting position to the non-mounting position.
Next, a case where the lock member 60 is held at the lock position while the platen roller shaft 23 is not held in the U-shaped groove 402 will be described with reference to FIG.
[0030]
In FIG. 9, when the cover frame 20 is rotated in the direction of arrow C, the pressing member 202 of the cover frame 20 presses the first cam portion a of the lock member 60, and further the cover frame 20 is rotated in the direction of arrow C. Then, the lock member 60 rotates so as to escape in the direction of arrow D, the claw b is opened, and the platen roller shaft 23 can move to the U-shaped groove 402. When the pressing member 202 of the cover frame 20 falls below the locking member 60, the pressing member 202 does not press the first cam portion a of the locking member 60, so that the locking member 60 moves in the direction opposite to the arrow D. The claw portion b holds the platen roller shaft 23 in the U-shaped groove 402. Note that the lock member 60 is rotated in the direction of arrow D by the pressing member 202 of the cover frame 20, but since the fourth cam portion g of the lock member 60 does not get over the protrusion 403 at that time, FIG. It is not held in the position.
[0031]
In the present embodiment, the case where the thermal paper P is used as the paper has been described as an example. However, paper other than the thermal paper can be used. For example, it is possible to use plain paper and use an inkjet head or the like instead of a line thermal head.
[0032]
【The invention's effect】
It is possible to provide a line thermal printer having a mechanism for accurately positioning a platen and a line thermal head.
Further, it is possible to simultaneously urge the line thermal head to the platen and hold the cover frame to the main body frame by one elastic member.
[Brief description of the drawings]
FIG. 1 is a schematic central sectional view of a printer according to the present invention when a cover frame is in a mounting position.
FIG. 2 is a schematic central sectional view of the printer according to the present invention when the cover frame is in a non-attached position.
FIG. 3 is a schematic top view of the printer according to the present invention when a cover frame is in a mounting position.
FIG. 4 is a schematic top view of the printer according to the present invention when the cover frame is in a non-mounted position.
FIG. 5 is a diagram showing a front end portion of a cover frame in the printer according to the present invention.
FIG. 6 is a view showing a lock member and the like when the cover frame is in the mounting position in the printer according to the present invention.
7 is a view showing a lock member and the like in a process in which the cover frame changes from the state shown in FIG. 6 to the state shown in FIG. 8 in the printer according to the present invention.
FIG. 8 is a view showing a lock member and the like when a cover frame is in a non-attached position in the printer according to the present invention.
FIG. 9 is a view showing a lock member and the like when the cover frame is in a non-attached position in the printer according to the present invention.
FIG. 10 is a perspective view showing a positional relationship among a line thermal head, an elastic member, a lock member, and the like.
FIG. 11 is a view showing a lock member.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Thermal roll 10 ... Base 11 ... 1st holding member 13 ... Bearing member 14 ... Guide member 20 ... Cover frame 21 ... Restricting member 22 ... Platen roller 23 ... Platen roller shaft 24 ... 1st engaging member 25 ... Fixed blade 28 ... Opening 30 ... Cutter unit 31 ... Movable blade 32 ... Second system coupling member 33 ... Swing support member 35 ... Stopper 40 ... Plate 42 ... Sensor 43 ... Line thermal head 44 ... Elastic member 45 ... Second holding member 47 ... the third engaging member 50 ... the elastic member 60 ... the locking member 70 ... the spacer 73 ... the support shaft 202 of the line thermal head ... the pressing member 402 ... the U-shaped grooves 403, 404 ... the projection a ... the first cam portion b of the locking member ... claw part c of lock member ... second cam part d of lock member ... handle part e of lock member ... bearing part f of lock member ... third cam part g of lock member ... Fourth cam portion of the click member

Claims (3)

A line thermal printer having a main body frame having a line thermal head, a lock member and an elastic member, and a cover frame having a platen,
The line thermal head is configured to be movable between a printing position close to the platen and a non-printing position retracted from the printing position.
The cover frame is configured to be movable between a mounting position for bringing the platen close to the line thermal head and a non-mounting position for retracting the platen from the line thermal head.
The lock member includes a holding portion that holds the cover frame in the mounting position and a bearing portion that rotatably supports the line thermal head, and the line thermal head is between the print position and the non-print position. In conjunction with the movement, the lock frame that holds the cover frame at the mounting position by the holding portion and the release position that releases the hold are configured to be rotatable.
The elastic member biases the line thermal head toward the print position, and biases the lock member toward the lock position.
A line thermal printer.   The cover frame has a pressing member, and when the locking member is located at the locking position, the pressing member presses the locking member toward the release position, whereby the cover frame is moved to the mounting position. The printer according to claim 1, wherein the printer is movable. The main body frame has a cutter unit having a movable blade,
The cover frame has a fixed blade for cutting paper in cooperation with the movable blade,
The cover frame is configured to cause the fixed blade to face the movable blade at the mounting position and to retract the fixed blade from the movable blade at the non-mounted position,
The cutter unit includes a non-cutting position where the cover frame can move from the non-mounting position to the mounting position, and a cutting position where the movable blade faces the fixed blade when the cover frame is in the mounting position. The printer according to claim 1 , wherein the printer is configured to be movable.

Images