JP4032951B2 - Printer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a printer that positions a platen provided on a lid frame with respect to a print head provided on a main body frame when the lid frame is closed.
[0002]
[Prior art]
2. Description of the Related Art Printers that store continuous paper such as roll paper and perform printing while pulling out the continuous paper are widely used. In this type of printer, when the continuous paper is replaced, it is necessary to manually pull out the continuous paper and place it along a predetermined paper path. By providing the exchange port on the side of the lid that opens and closes, the paper path is configured to open along with the opening operation of the lid.
[0003]
When the print head is a dot impact method or an ink jet method, a predetermined gap (platen gap) is secured between the print head and the platen in order to secure the print quality, and the platen is attached to the print head. It is required to be arranged parallel to the print line.
[0004]
[Problems to be solved by the invention]
However, in the above-described conventional printer, since the platen is positioned by the engagement of the lock lever provided rotatably on the lid frame and the lock pin provided on the main frame, the mounting frame of the lid frame with respect to the main frame is fixed. May affect the positioning accuracy of the platen.
[0005]
An object of the present invention is to position the platen provided on the lid frame with respect to the print head provided on the main body frame when the lid frame is closed. It is possible to accurately position the platen with respect to the print head without being affected by the above, and as a result, a predetermined gap is secured between the print head and the platen, and the platen is connected to the print line of the print head. It is an object of the present invention to provide a printer that can be arranged in parallel with each other to improve print quality.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, a printer of the present invention includes a print head provided on a main body frame, a lid frame provided on the main body frame so as to freely open and close, and a platen provided on the lid frame. A first positioning mechanism that faces the print head with a predetermined gap when the body frame is closed, and a first positioning mechanism that positions the platen with respect to the print head when the lid frame is closed The position change of the platen caused by the backlash or the like of the lid frame with respect to the main body frame is centered on the first positioning groove of the platen that engages with the first positioning fulcrum provided on the main body frame. and limiting the rotation of the lid frame, when the lid frame is closed, the platen relative to the printing head A second positioning mechanism for positioning, the rotation of the platen around the first positioning fulcrum, the second positioning fulcrum provided in the lid frame side is formed on the body frame And the one that is regulated by contacting the second positioning groove .
[0007]
Further, it is preferable that the first positioning fulcrum is disposed on a virtual straight line that passes through the print position of the print head and is substantially perpendicular to the print head facing surface of the platen in a side view. In this case, since the amount of change in the platen gap accompanying the rotation of the platen is minimized, the accuracy of the platen gap can be increased and the printing quality can be improved.
[0010]
Furthermore, a paper feed roller provided on one of the main body frame or the lid frame and a paper pressing roller provided on the other of the main body frame or the lid frame, the lid frame being closed The first positioning fulcrum is disposed at a position deviating from a virtual straight line passing through the center of the paper feed roller and the center of the paper presser roller in a side view. It is preferable. In this case, since the moment acting in a fixed direction around the first positioning fulcrum acts on the platen due to the drag acting on the paper pressing roller, the contact position between the second positioning fulcrum and the second positioning groove is determined. The positioning accuracy of the platen can be further improved.
[0011]
Furthermore, it is preferable that a spring for urging the paper pressing roller toward the paper feeding roller is provided. In this case, since a certain drag force (spring force) acts on the paper pressing roller, a moment in a certain direction can be surely acted on the platen.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 is a perspective view of the printer unit showing a state in which the lid frame is closed, FIG. 2 is a perspective view of the printer unit showing a state in which the lid frame is opened (half-opened state), and FIG. It is a perspective view of a printer unit showing an opened state (fully opened state). The printer unit 10 shown in these drawings constitutes a printer by being incorporated in a predetermined housing. The printer unit 10 includes a storage unit 11 that stores a roll-shaped continuous paper P therein, and one end side of the continuous paper P that is rotatably held in the storage unit 11 passes through a paper path 12. It is pulled out from the upper part of the printer unit 10. On the paper path 12, a paper feed roller 13 that conveys the continuous paper P, a paper press roller 14 that presses the continuous paper P against the paper feed roller 13, and a dot impact type print head 15 that performs printing on the continuous paper P. And a platen 16 that holds the back surface of the continuous paper P at a position facing the print head 15.
[0013]
The print head 15 is provided on a carriage 17 that reciprocates in the left-right direction (the width direction of the paper path 12). An ink ribbon is supplied from the ink ribbon cassette 18 to the moving area of the print head 15, and the impact pin of the print head 15 is caused to project while the ink ribbon is interposed between the print head 15 and the continuous paper P. The dot matrix printing is performed on the continuous paper P.
[0014]
An opening 19 for exchanging the continuous paper P or the like is formed above the storage unit 11. Side frames 20a constituting a part of the main body frame 20 are erected on both the left and right sides of the storage unit 11, and the opening 19 is formed by a lid frame 21 provided at the rear part of the side frame 20a so as to be rotatable up and down. Is opened and closed. The lid frame 21 is provided with the platen 16 and the paper pressing roller 14 at the tip thereof. When the lid frame 21 is opened, the platen 16 and the paper pressing roller 14 are retracted, and the paper path 12 is opened. . That is, when exchanging the continuous paper P, the lid frame 21 is opened and the continuous paper P is stored in the storage unit 11, and then one end side of the continuous paper P is pulled out of the housing, and in this state the lid frame By closing 21, the continuous paper P is set along the paper path 12. A motor 30 for driving the paper feed roller 13 is fixed outside the one side frame 20a. A train wheel 31 for transmitting the power of the motor 30 to the paper feed roller 13 is provided outside the side frame 20a. 4 is a perspective view of main parts of the printer unit showing a state in which the lid frame is closed, FIG. 5 is a perspective view of relevant parts of the printer unit in a state in which the lid frame is opened, and FIG. It is a disassembled perspective view. As shown in these drawings, the platen 16 includes an attachment surface 16a that is integrally attached to the lower surface on the front end side of the lid frame 21, and a downstream guide surface 16b that guides the continuous paper P on the downstream side of the print head 15. And a print head facing surface 16c (platen working surface) facing the print head 15 with a predetermined gap, and an upstream guide surface 16d for guiding the continuous paper P on the upstream side of the print head 15. A paper pressing roller 14 is rotatably held on the back side of the platen 16, and the paper pressing roller 14 protruding from a roller protruding hole 16 e formed in the upstream guide surface 16 d is brought into contact with the paper feeding roller 13. . When the lid frame 21 is closed, the print head facing surface 16c is required to maintain a predetermined gap between the print head 15 and the print head 15 in parallel with the print line of the print head 15. The Hereinafter, the first positioning mechanism 22 and the second positioning mechanism 23 that position the platen 16 with respect to the print head 15 will be described.
[0015]
FIG. 7 is a vertical sectional view of the main part of the printer unit showing the process of closing the lid frame, FIG. 8 is a vertical sectional view of the main part of the printer unit immediately before the lid frame is closed, and FIG. FIG. 4 is a longitudinal sectional view of a main part of the printer unit showing a state where a frame is closed. As shown in these drawings, the first positioning mechanism 22 is rotated around a pair of left and right lock pins (first positioning fulcrum) 24 projecting on the inner surface of the side frame 20 a and the left and right side plate portions 16 f of the platen 16. A lock lever support shaft 25 that is movably supported, a pair of left and right lock levers 26 that can be rotated back and forth with the lock lever support shaft 25 as a fulcrum, and a pair of left and right side plates 16e formed on the left and right side plate portions 16e of the platen 16. 1 positioning groove 16g.
[0016]
The left and right lock levers 26 are integrally connected via a connecting portion 26a, and are attached to the rear by a spring 27 interposed in a compressed state between the connecting portion 26a and the shaft portion of the paper pressing roller 14. Be forced. An engagement hook groove 26 b and a tapered portion 26 c are formed at the tip of the lock lever 26. When the lid frame 21 is closed, the tapered portion 26c hits the lock pin 24 before the closed position, and rotates the lock lever 26 forward by the tilt guide action (FIG. 8). As shown in FIG. 9, when the lid frame 21 reaches the closed position, the lock lever 26 moves backward (in the direction of arrow A in FIG. 9) by the biasing force of the spring 27 as the tapered portion 26 c gets over the lock pin 24. ). At this time, the engagement hook groove 26b is engaged with the lock pin 24, so that the opening / closing operation of the lid frame 21 is locked. A lock release lever 28 is rotatably provided at one end of the lock lever support shaft 25, and the lock lever 26 is rotated forward (in the direction of arrow B in FIG. 9) in accordance with the backward rotation operation. By moving, the open / close lock of the lid frame 21 is released.
[0017]
The first positioning groove 16g is formed at the lower end portion of the side plate portion 16f so that the lower side opens in a divergent shape. As shown in FIG. 8, when the lid frame 21 is closed, one groove inner edge of the first positioning groove 16g contacts the lock pin 24, and the platen 16 is positioned and guided. Further, as shown in FIG. 9, when the lid frame 21 reaches the closed position, the platen 16 is positioned by engaging the groove upper end portion 16h of the first positioning groove 16g with the lock pin 24. It is held by the engagement between the lock pin 24 and the lock lever 26. The groove upper end portion 16 h of the first positioning groove 16 g and the engagement hook groove 26 b of the lock lever 26 are both formed in an arc shape along the outer periphery of the lock pin 24. Therefore, in the fully closed state in which the groove upper end portion 16 h of the first positioning groove 16 g and the engagement hook groove 26 b of the lock lever 26 are engaged with the lock pin 24, the position change of the platen 16 rotates around the lock pin 24. Limited to movement.
[0018]
As shown in FIG. 9, the lock pin 24 that is a positioning fulcrum of the first positioning mechanism 22 is disposed on the first virtual straight line L <b> 1 in a side view. The first virtual straight line L1 passes through the print position 15a of the print head 15 in a side view and is substantially perpendicular to the print head facing surface 16c of the platen 16, and is on the first virtual straight line L1. By disposing the lock pin 24, the amount of change in the platen gap accompanying the rotation of the platen 16 is minimized.
[0019]
The second positioning mechanism 23 includes the lock lever support shaft (second positioning fulcrum) 25 and a pair of left and right second positioning grooves 20b formed on the left and right side frames 20a. The 2nd positioning groove 20b is formed in the upper end part of the side frame 20a so that an upper side may open in the shape of the end. As shown in FIG. 8, when the lid frame 21 is closed, the left and right ends of the lock lever support shaft 25 come into contact with the inner edge of one of the second positioning grooves 20b, and the platen 16 is positioned and guided. As shown in FIG. 9, when the lid frame 21 reaches the closed position, both end portions of the lock lever support shaft 25 enter the narrow portion 20c of the second positioning groove 20b. The narrow portion 20c is set to have a groove width that is slightly larger than the diameter of the lock lever support shaft 25. When the lock lever support shaft 25 is positioned here, the lock lever support shaft 25 is the second portion. By contacting the inner edge of the positioning groove 20b, the rotation of the platen 16 around the lock pin 24 is restricted.
[0020]
Meanwhile, as shown in FIG. 10, a roller holder 29 that supports the paper pressing roller 14 and the spring 27 is provided on the back side of the platen 16. The roller holder 29 is integrally fixed to the platen 16 by engaging with the lock lever support shaft 25 and the roller protruding hole 16e. The roller holder 29 is formed with a roller support groove 29 a that rotatably supports the paper pressing roller shaft 14 a and a protrusion 29 b that supports the spring 27. The roller support groove 29a has a long hole shape, and not only supports the paper pressing roller shaft 14a so as to be rotatable, but also the direction of the second virtual straight line L2 passing through the centers of the paper feeding roller 13 and the paper pressing roller 14. The paper presser roller shaft 14a is slidably supported. The protrusion 29b is a bent piece facing in the left-right direction, and a spring 27 is attached from one side thereof. As described above, the spring 27 not only urges the lock lever 26 rearward but also urges the paper pressing roller shaft 14a downward, so that the paper pressing roller 14 protrudes from the roller protrusion hole 16e. Is done. When the paper pressing roller 14 is separated from the paper feeding roller 13, that is, when the lid frame 21 is opened, both ends of the paper pressing roller shaft 14 a urged by the spring 27 are brought into contact with the back surface of the platen 16. In contact therewith, further protrusion of the paper pressing roller 14 is restricted. On the other hand, when the lid frame 21 is closed, the paper pressing roller 14 contacts the paper feeding roller 13 and moves backward to the back side of the platen 16. At this time, the paper feed roller 13 is pressed against the paper presser roller 14 with a constant force (biasing force of the spring 27), and accordingly, the paper presser roller 14 is pressed against the paper presser roller 14 by a certain drag (applying spring 27). Equivalent to power).
[0021]
As shown in FIG. 9, the lock pin 24, which is the first positioning fulcrum, is disposed at a position offset from the second virtual straight line L2 by a predetermined amount in a side view. For this reason, a moment in a certain direction around the lock pin 24 acts on the platen 16 due to the drag acting on the paper pressing roller 14. That is, because of this moment, the platen 16 is always rotated in a fixed direction with the lock pin 24 as a fulcrum, so the contact position between the lock lever support shaft 25 and the second positioning groove 20b is specified, and the second positioning mechanism 23 It is possible to increase the positioning accuracy in
[0022]
FIG. 11 is a vertical cross-sectional view of the main part showing a state in which the lid frame of the printer unit in another embodiment of the present invention is closed. In addition, the code | symbol same as FIGS. 1-10 among the code | symbol shown in FIG. 11 shows the same element, and detailed description is abbreviate | omitted.
[0023]
In the embodiment shown in FIGS. 1 to 10, the paper feed roller 13 and the paper pressing roller 14 are arranged on the upstream side of the print head 15 in the paper path 12. It is arranged downstream of the print head 15. That is, the roller guide hole 16e is provided in the downstream guide surface 16b of the platen 16, and the paper feed roller 13 protrudes therefrom. The paper pressing roller is rotatably supported by the upper portion of the side frame 20a, and comes into pressure contact with the paper feed roller 13 protruding from the roller protruding hole 16e when the lid frame 21 is closed. ing. That is, in the embodiment shown in FIGS. 1 to 10, the continuous paper P is pushed and conveyed from the upstream side toward the printing position 15a, whereas in the present embodiment, the continuous paper P is continuous from the downstream side of the printing position 15a. The paper P is conveyed so as to be pulled.
[0024]
In the embodiment shown in FIGS. 1 to 10, the paper feed roller 13 is provided on the main body frame 20 side, and the paper pressing roller 14 is provided on the lid frame 21 side. The feed roller 13 is provided on the lid frame 21 side, and the paper pressing roller 14 is provided on the main body frame 20 side. For this reason, a gear (not shown) is provided at one end of the support shaft of the paper feed roller 13, and the gear meshes with the train wheel 31 in a state where the lid frame 21 is closed. Power is transmitted to the paper feed roller 13.
[0025]
In the embodiment shown in FIGS. 1 to 10, the spring 27 urges the lock lever 26 to the rear and urges the paper pressing roller 14 to the paper feed roller 13. The sheet pressing roller 14 is urged toward the sheet feeding roller 13 by the plate spring 271, and the lock lever 26 is urged rearward by the coil spring 272.
[0026]
Similarly to FIG. 9, in the example shown in FIG. 11, the lock pin 24 that is the first positioning fulcrum is the second virtual straight line L <b> 2 that passes through the centers of the paper pressing roller 14 and the paper feeding roller 13 in the side view. Because of the drag acting on the paper pressing roller 14, a moment in a certain direction around the lock pin 24 acts on the platen 16, and the second positioning mechanism The positioning accuracy at 23 can be increased.
[0027]
As described above, according to these embodiments, the printer unit 10 includes the print head 15 provided on the main body frame 20, the lid frame 21 provided on the main body frame 20 so as to freely open and close, and the lid frame 21. When the lid frame 21 is closed, facing the print head 15 with a predetermined gap, and when the lid frame 21 is closed, the platen 16 is provided. A first positioning mechanism 22 for positioning 16 with respect to the print head 15, wherein the change in position of the platen 16 is limited only to rotation about the first positioning fulcrum (lock pin 24); A second positioning mechanism 23 that positions the platen 16 with respect to the print head 15 when the lid frame 21 is closed. It, constituted by a one rotation of the platen 16 around the first positioning fulcrum is restricted by abutment of the second positioning fulcrum (the lock lever spindle 25). That is, the position change of the platen 16 is limited only to the rotation by the first positioning mechanism 22 and the rotation is restricted by the second positioning mechanism 23. The platen 16 can be accurately positioned with respect to the print head 15 without being affected. As a result, a predetermined gap can be secured between the print head 15 and the platen 16, and the platen 16 can be arranged in parallel to the print line of the print head 15 to improve the print quality.
[0028]
In a side view, the first positioning fulcrum (lock pin 24) passes through the print position 15a of the print head 15 and on a first virtual straight line L1 that is substantially perpendicular to the print head facing surface 16c of the platen 16. ) Is arranged, the amount of change in the platen gap accompanying the rotation of the platen 16 can be minimized, and as a result, the accuracy of the platen gap can be increased and the printing quality can be improved.
[0029]
The first positioning mechanism 22 is provided on the main body frame 20, and is a lock pin 24 serving as the first positioning fulcrum, and a lock lever provided rotatably on the platen 16 via a lock lever support shaft 25. A first positioning groove 16g provided in the platen 16 and the first positioning groove 16g provided in the platen 16 when the lid frame 21 is closed, which engages with the lock pin 24 to lock the opening / closing operation of the lid frame 21. When the lid frame 21 is closed, the position change of the platen 16 is limited to the rotation around the lock pin 24 by being along the outer periphery of the lock pin 24. Therefore, the first positioning mechanism 22 is configured with a simple change that adds the first positioning groove 16g to the conventional lock lever mechanism. Bets can be, as a result, it is possible to simplify the reduction and structure of parts.
[0030]
The second positioning mechanism 23 is provided on the platen 16 and includes the lock lever support shaft 25 serving as the second positioning fulcrum and the second positioning groove 20b provided in the main body frame 20, and the lid When the body frame 21 is closed, the lock lever support shaft 25 abuts against the inner edge of the groove, thereby restricting the rotation of the platen 16 around the lock pin 24. Therefore, the second positioning mechanism 23 can be configured using the lock lever support shaft 25. As a result, the number of parts can be reduced and the structure can be simplified. Moreover, since the distance between the first positioning fulcrum and the second positioning fulcrum can be kept constant by the lock lever 26, the positioning accuracy of the platen 16 can be further improved.
[0031]
Further, a paper feed roller 13 provided on the main body frame 20 and a paper presser roller 14 provided on the lid frame 21, and when the lid frame 21 is closed, A lock pin 24 (first positioning fulcrum) is disposed at a position deviating from a second imaginary straight line L2 passing through the center of the paper feed roller 13 and the center of the paper pressing roller 14 in a side view. Therefore, the drag acting on the paper pressing roller 14 causes a moment in a certain direction around the lock pin 24 to act on the platen 16, and as a result, the lock lever support shaft 25 (second positioning fulcrum) and the second The contact position with the positioning groove 20b can be specified, and the positioning accuracy of the platen 16 can be further improved.
[0032]
Further, since the paper pressing roller 14 is provided with springs 27 and 271 for urging the paper pressing roller 14 toward the paper feeding roller 13, a certain drag force (spring force) can be applied to the paper pressing roller 14, and as a result, A moment in a certain direction can be reliably applied to the platen 16, and the positioning accuracy in the second positioning mechanism 23 can be improved.
[0033]
As mentioned above, although one embodiment of the present invention has been described with reference to the drawings, the present invention is not limited to the matters shown in the embodiment, and the description of the claims and the detailed description of the invention, as well as the well-known technology Based on the above, a range in which those skilled in the art can make changes and applications thereof is included.
[0034]
【The invention's effect】
As described above, according to the present invention, when the lid frame is closed, the platen provided on the lid frame is positioned with respect to the print head provided on the main body frame. The platen can be accurately positioned with respect to the print head without being affected by frame mounting play, etc. As a result, a predetermined gap is secured between the print head and the platen, and the platen is printed. The print quality can be improved by arranging the print head parallel to the print line of the head.
[Brief description of the drawings]
FIG. 1 is a perspective view illustrating a state in which a lid frame of a printer unit according to an embodiment of the present invention is closed.
2 is a perspective view showing a state in which a lid frame is opened (half-opened state) in the printer unit of FIG. 1; FIG.
3 is a perspective view showing a state in which a lid frame is opened (fully opened state) in the printer unit of FIG. 1; FIG.
4 is a perspective view of a principal part showing a state in which a lid frame is closed in the printer unit of FIG. 1; FIG.
5 is a perspective view of the main part showing a state in which a lid frame is opened in the printer unit of FIG. 1; FIG.
6 is an exploded perspective view of a lid frame of the printer unit of FIG. 1. FIG.
7 is a longitudinal sectional view of a main part showing a process in which a lid frame is closed in the printer unit of FIG. 1; FIG.
FIG. 8 is a longitudinal sectional view of a main part showing a state immediately before the lid frame is closed in the printer unit of FIG. 1;
9 is a longitudinal sectional view of a main part showing a state in which a lid frame is closed in the printer unit of FIG. 1;
10 is a perspective view of a platen of the printer unit of FIG. 1 as viewed from the back side.
FIG. 11 is a longitudinal sectional view of a main part showing a state in which a lid frame of a printer unit according to another embodiment of the present invention is closed.
[Explanation of symbols]
P Continuous paper L1 First virtual straight line L2 Second virtual straight line 10 Printer unit 11 Storage unit 13 Paper feed roller 14 Paper pressing roller 15 Print head 15a Print position 16 Platen 16c Print head facing surface 16g First positioning groove 20 Main body frame 20a Side Frame 20b Second positioning groove 21 Lid frame 22 First positioning mechanism 23 Second positioning mechanism 24 Lock pin 25 Lock lever support shaft 26 Lock lever 27 Spring 29 Roller holder

Claims (4)

A print head provided on the main body frame;
A lid frame provided on the main body frame so as to freely open and close;
A platen provided in the lid frame, which faces the print head with a predetermined gap when the lid frame is closed;
When the lid frame is closed, a first positioning mechanism that positions the platen with respect to the print head, and changes in the position of the platen caused by the backlash and the like of the lid frame with respect to the main body frame , Limited to rotation of the lid frame around the first positioning groove of the platen that engages with a first positioning fulcrum provided on the body frame ;
A second positioning mechanism for positioning the platen with respect to the print head when the lid frame is closed, wherein the lid is rotated around the first positioning fulcrum. The second positioning fulcrum provided on the frame side is regulated by coming into contact with the second positioning groove formed in the main body frame ;
A printer comprising:   The first positioning fulcrum is disposed on a virtual straight line that passes through the print position of the print head and is substantially perpendicular to the print head facing surface of the platen in a side view. Printer. A paper feed roller provided on one of the main body frame or the lid frame, and a paper pressing roller provided on the other of the main body frame or the lid frame, and when the lid frame is closed, the paper The first positioning fulcrum is disposed at a position deviating from a virtual straight line passing through the center of the paper feed roller and the center of the paper presser roller in a side view. The printer according to claim 1 or 2. The printer according to claim 3, further comprising a spring that biases the paper pressing roller toward the paper feeding roller.

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