JP2000094770A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance print quality by ensuring a correct head gap corresponding to the thickness of a print sheet. SOLUTION: The printer comprises first and second guide members extending in the scanning direction, a carriage 12, a print head 11, a print sheet carrying passage 10, a first fixed roller disposed on the upstream side of the print head 11, a first movable roller disposed to move while abutting against the first fixed roller, a second fixed roller disposed on the downstream side of the print head 11, a second movable roller disposed to move while abutting against the second fixed roller, and a mechanism for coupling one of the first or second movable rollers with the carriage 12 and turning the print head 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer.

[0002]

2. Description of the Related Art Conventionally, in a printer device, a carriage is run along a guide shaft and a guide rail, and printing is performed by a print head mounted on the carriage. FIG. 2 is a sectional view showing a first state of the conventional printer, and FIG. 3 is a sectional view showing a second state of the conventional printer.

In FIG. 1, reference numeral 11 denotes a print head, 12 denotes a carriage for mounting the print head 11, 13 denotes a guide shaft, 14 denotes a guide rail disposed in parallel with the guide shaft 13, and 15 denotes a base frame. Yes,
The carriage 12 runs along a guide shaft 13 and a guide rail 14. Then, the printing paper P conveyed in the direction of arrow A onto the base frame 15
Is formed.

The print head 11 in the transport path 10
In order to transport the printing paper P with the printing paper P interposed therebetween, the first upstream side is rotatable relative to the base frame 15.
And a plurality of pinch rollers 25 are disposed so as to be rotatable and vertically movable in contact with the first feed roller 24. For this purpose, a roller holder 26 is disposed so as to be swingable about a fulcrum 27, and the pinch roller 25 is rotatably disposed at one end of the roller holder 26. A spring S1 is stretched between the other end of the roller holder 26 and the frame 50, and the spring S1 urges the roller holder 26 clockwise in the drawing.

A second feed roller 29 is rotatable with respect to the base frame 15 on the downstream side of the print head 11 in the transport path 10 in order to transport the print paper P in a state of being sandwiched therebetween. A plurality of spur rollers 4 are disposed in contact with the second feed roller 29 and
0 is disposed so as to be rotatable and movable in the vertical direction. For this purpose, the roller holder 30 is provided so as to be swingable about a fulcrum 31 and the spur roller 40 is provided at one end of the roller holder 30 so as to be freely rotatable. A spring S2 is stretched between one end of the roller holder 30 and the guide rail 14, and the spring S2
Urges the roller holder 30 in the counterclockwise direction in the figure.

In the printer having the above configuration, the printing paper P fed to the transport path 10 is sandwiched between the first feed roller 24 and the pinch roller 25. Here, while the first feed roller 24 is rotated at the same position, the pinch roller 25 is moved with the rotation of the roller holder 26 in the direction of arrow B, and is rotated at a predetermined position. Let me do. Therefore, the pinch roller 25
Moves upward by a distance equal to the thickness t of the fed printing paper P, and conveys the printing paper P with the first feeding roller 24 interposed therebetween.

Subsequently, the printing paper P on which printing has been performed by the printing head 11 is sandwiched between the second feed roller 29 and the spur roller 40. Here, while the second feed roller 29 is rotated at the same position, the spur roller 40 is moved with the rotation of the roller holder 30 in the direction of the arrow C, and rotated at a predetermined position. Let me do. Therefore, the spur roller 40 moves upward by a distance equal to the thickness t, and discharges the print paper P with the second feed roller 29 interposed therebetween.

By the way, as the thickness t of the printing paper P increases, the distance between the printing head 11 and the printing paper P, that is, the head gap decreases. Therefore, if the print paper P has wrinkles, undulations, or the like, the print head 11 and the print paper P come into contact with each other, causing printing stains and the like. Therefore, by moving the guide shaft 13 or the guide rail 14 upward in accordance with the thickness t of the printing paper P, an appropriate head gap can be secured.

[0009]

However, in the above-mentioned conventional printer apparatus, if an attempt is made to secure an appropriate head gap by moving the guide shaft 13 or the guide rail 14, the print head 11 and the print paper P are separated. Since the print heads 11 are not parallel and the print head 11 is inclined with respect to the print paper P, of the plurality of dots formed in the transport direction of the print paper P by the print head 11, the first dot and the last dot are different. A difference occurs in the head gap. Therefore, the print quality deteriorates.

Therefore, by moving the guide shaft 13 and the guide rail 14 upward by the same distance, it is conceivable to secure an appropriate head gap while keeping the print head 11 and the print paper P parallel. However, the printing mechanism becomes complicated, and the size of the printer becomes large. The present invention solves the problems of the conventional printer device, can secure an appropriate head gap corresponding to the thickness of the printing paper, can improve the printing quality, and can simplify the printing mechanism. It is an object of the present invention to provide a printer device that can be downsized and downsized.

[0011]

For this purpose, in the printer device of the present invention, a first guide member provided to extend in the scanning direction and a first guide member extending in parallel with the first guide member. A second guide member, a carriage that runs along the first and second guide members, a print head that is mounted on the carriage and prints on print paper, A transport path formed in a direction perpendicular to the scanning direction, for transporting the print paper, a first fixed roller disposed on the transport path upstream of the print head, A first movable roller movably disposed in contact with the fixed roller, a second fixed roller disposed downstream of the print head in the transport path, and the second fixed roller A second movable member that is movably disposed in contact with Rollers for connecting one of the first and second movable rollers to the carriage, and rotating the print head with movement of one of the first and second movable rollers. And a coupling mechanism.

The first and second movable rollers are:
They are disposed on opposite sides of the printing paper.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view showing a first state of a printer according to an embodiment of the present invention, FIG. 4 is a perspective view of the printer according to an embodiment of the present invention, and FIG. 5 is a printer according to an embodiment of the present invention. It is sectional drawing which shows the 2nd state of.

In FIG. 1, reference numeral 11 denotes a print head for ejecting ink droplets (not shown) toward a printing paper P to print on the printing paper P; 12, a carriage for mounting the printing head 11; A guide shaft as a first guide member extending in a direction perpendicular to the direction of conveyance of the printing paper P (direction of arrow A),
Reference numeral 14 denotes a guide rail as a second guide member disposed to extend in parallel with the guide shaft 13;
Is a base frame, and 50 is a frame that supports the guide shaft 13. The carriage 12 is connected to a motor 16 as a first drive source via a belt 17, and is driven along the guide shaft 13 and the guide rail 14 by driving the motor 16.
A transport path 10 for the printing paper P is formed between the printing head 11 and the base frame 15 in a direction perpendicular to the scanning direction.

The guide shaft 13 is mounted on the frame 50 via an eccentric cam 41 so as to be movable vertically and rotatable. For this purpose, an elliptical guide support hole 50a is formed in the frame 50, and the guide shaft 13 passes through the guide support hole 50a. The eccentric cam 41 is fitted (engaged) with both ends of the guide shaft 13, and is rotatably disposed at both ends of the guide shaft 13 in synchronization with the roller holder 26 connected via the connecting rod 42. . The frame 50 is formed to be curved at the entrance end of the transport path 10 so that the print paper P can be smoothly guided below the print head 11. The roller holder 26, the eccentric cam 41 and the connecting rod 42 constitute a connecting mechanism.

On the upstream side of the print head 11 in the transport path 10, in order to transport the print paper P in a state of being sandwiched, a first fixed roller as a first fixed roller is rotatable with respect to the base frame 15. A first feed roller 24 is disposed so as to face the back surface of the printing paper P, and is brought into contact with the first feed roller 24 so as to be rotatable and vertically movable. A pinch roller 25 as a movable roller is disposed so as to face the surface of the printing paper P. For this purpose, the roller holder 26 is disposed so as to be swingable about a fulcrum 27, and the pinch roller 25 is disposed at one end of the roller holder 26 so as to be rotatable. A spring S1 is stretched between the other end of the roller holder 26 and the frame 50, and the spring S1 urges the roller holder 26 clockwise in the drawing. Therefore, the printing paper P is sandwiched between the first feed roller 24 and the pinch roller 25. The first feed roller 24 is connected to a motor 18 as a second drive source via gears 19 to 22.

In order to convey the printing paper P in a state downstream of the printing head 11 in the conveyance path 10, the printing paper P is rotatable relative to the base frame 15 and moved vertically. A second feed roller 29 is freely disposed as a second movable roller so as to face the back surface of the printing paper P, and the second feed roller 29 is provided.
, A plurality of spur rollers 40 as second fixed rollers are rotatably disposed facing the surface of the printing paper P. Therefore, the second feed roller 29
The printing paper P is sandwiched by the spur roller 40 and the spur roller 40. For this purpose, the second feed roller 29 is supported by a roller holder 32 and is urged toward the spur roller 40 by an elastic member 33 disposed between the roller holder 32 and the base frame 15. Is done.
A roller holder 30 is fixed to the guide rail 14, and the spur roller 40 is attached to the tip of the roller holder 30.
Are rotatably arranged. The spur roller 40 is provided with a plurality of teeth on an outer peripheral edge thereof and formed in a spur shape so that ink (not shown) on the printing paper P immediately after printing is suppressed. The second feed roller 29 and the first feed roller 24 are connected via gears 61 to 63.

The contact surfaces of the first and second feed rollers 24 and 29 with the printing paper P are formed of a material such as rubber. Next, the operation of the printer device having the above configuration will be described. First, when the printer receives a print start and paper feed command from the outside, the print paper P is fed by a paper feed device such as an external hopper (not shown) and supplied to the transport path 10. Then, as shown in FIG. 5, as the printing paper P is sandwiched by the first feed roller 24 and the pinch roller 25, the roller holder 26 is rotated in the direction of arrow B about the fulcrum 27, The pinch roller 25 is moved upward with the rotation of the roller holder 26.

At this time, with the rotation of the roller holder 26 in the direction of arrow B, the connecting rod 42 is pulled downward in FIG. 5, and the eccentric cam 41 connected to the connecting rod 42 is rotated in the direction of arrow D. The cam surface is moved along the receiving surface 43 formed on the frame 50. The guide shaft 13 has a circular cross section, whereas the guide support hole 50a has an elliptical shape.
Is supported movably in the vertical direction with respect to the frame 50. Therefore, the printing paper P is transferred to the first feed roller 2.
4 and the pinch roller 25, the guide shaft 13 is moved upward in the guide support hole 50a, whereby the carriage 12 and the print head 11 are moved.
Is a contact point M1 between the carriage 12 and the guide rail 14.
Is rotated clockwise around the center. In this state, the first feed roller 24 is driven by driving the motor 18.
Is rotated, the printing paper P becomes the first feed roller 2
4 and is transported by contact friction.

Thereafter, when the front end of the print paper P reaches the print head 11 with the conveyance, printing is performed on the print paper P by the print head 11 and the front end of the print paper P is moved to the second feed roller 29. When the printing paper P reaches between the spur roller 40 and the spur roller 40, the printing paper P is sandwiched between the second feed roller 29 and the spur roller 40. The spur roller 40 is a roller holder 30 fixed to the guide rail 14.
, And does not move in the vertical direction.
Is sandwiched between the second feed roller 29 and the spur roller 40, the second feed roller 29 is moved downward (in the direction of arrow E) by the thickness t of the printing paper P.

Therefore, the printing paper P is tilted clockwise, the printing head 11 and the printing paper P are parallel, and an appropriate head gap is secured between the printing head 11 and the printing paper P. As a result, the printing paper P becomes wrinkled,
Even if there is undulation or the like, the print head 11 and the print paper P do not come into contact with each other.

Further, since the print head 11 and the print paper P are parallel to each other and the print head 11 is not inclined with respect to the print paper P, a plurality of dots formed by the print head 11 in the transport direction of the print paper P are formed. Of these, there is no difference in head gap between the first dot and the last dot. Therefore, not only can the print quality be improved, but also the range in which the print head 11 can perform printing in one scan can be widened, and the throughput can be improved.

Since there is no need to move the guide shaft 13 and the guide rail 14 upward by the same distance, the printing mechanism can be simplified and the printer can be downsized. In addition, since the guide rails 14 are fixed, the carriage 12 can be stably moved based on the guide rails 14. Therefore, the carriage 12 and the printing paper P can be easily made parallel.

Further, since the print head 11 is rotated in conjunction with the vertical movement of the pinch roller 25, the number of parts can be reduced and the cost of the printer device can be reduced. it can. Since the first feed roller 24 is fixed to the base frame 15 so as not to move in the vertical direction, the motor 18 and the first feed roller 24 are easily connected via the gears 19 to 22. can do.

In this embodiment, the pinch roller 2
5 is moved up and down to rotate the carriage 12 and the print head 11 clockwise, but the spur roller 40 is moved up and down to
Also, the print head 11 can be rotated counterclockwise. It should be noted that the present invention is not limited to the above-described embodiment, but can be variously modified based on the gist of the present invention, and they are not excluded from the scope of the present invention.

[0026]

As described above in detail, according to the present invention, in the printer apparatus, the first guide member extending in the scanning direction and the first guide member are provided. A second guide member extending parallel to the first and second guide members, a carriage running along the first and second guide members, and mounted on the carriage to perform printing on printing paper. A print head, a transport path formed in a direction perpendicular to the scanning direction, and for transporting the print paper,
A first fixed roller disposed upstream of the print head in the transport path, a first movable roller movably disposed in contact with the first fixed roller, and the transport path; The second is disposed downstream from the print head in
A fixed roller, a second movable roller movably disposed in contact with the second fixed roller, and the first and second fixed rollers.
And a connection mechanism for connecting one of the movable rollers to the carriage and rotating the print head in accordance with the movement of one of the first and second movable rollers.

The first and second movable rollers are:
They are disposed on opposite sides of the printing paper. In this case, when the printing paper is sandwiched between the first fixed roller and the first movable roller, and the second fixed roller and the second movable roller, the printing head is rotated and the printing paper is tilted. Thus, an appropriate head gap is secured between the print head and the printing paper.

Therefore, even if the printing paper has wrinkles or undulations, the printing head and the printing paper do not come into contact with each other, so that it is possible to prevent the occurrence of printing stains and the like. Also, since the print head and the print paper are parallel and the print head does not tilt with respect to the print paper, of the plurality of dots formed in the print paper transport direction by the print head, the first dot and the final dot There is no difference in the head gap between the dot and the dot. Therefore, not only can the print quality be improved, but also the range over which the print head can perform printing in one scan can be widened, and the throughput can be improved.

Since it is not necessary to move the first and second guide members upward by the same distance, the printing mechanism can be simplified and the printer can be downsized. Moreover, since one of the first and second guide members is fixed, the carriage can be stably moved based on one of the first and second guide members. Therefore, the carriage and the printing paper can be easily made parallel.

Further, since the print head is rotated in conjunction with the movement of one of the first and second movable rollers, the number of parts can be reduced, and the cost of the printer is reduced. Can be lowered. Since the first fixed roller is fixed so as not to move, the motor and the first fixed roller can be easily connected via a gear.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first state of a printer device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a first state of a conventional printer device.

FIG. 3 is a sectional view showing a second state of the conventional printer.

FIG. 4 is a perspective view of the printer device according to the embodiment of the present invention.

FIG. 5 is a sectional view showing a second state of the printer device according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Conveying path 11 Print head 12 Carriage 13 Guide shaft 14 Guide rail 24 First feed roller 25 Pinch roller 26 Roller holder 29 Second feed roller 40 Spur roller 41 Eccentric cam 42 Connecting rod P Print paper

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C059 AA22 AA24 AA26 BB02 BB06 BB07 BB11 BB13 BB27 CC20 2C064 CC04 CC05 CC11 DD01 DD12 DD13 DD15 3F049 AA01 CA31 DA12 DB02 LA07 LB03

Claims (3)

[Claims] 1. A first guide member extending in the scanning direction and a second guide member extending in parallel with the first guide member. (C) a carriage that runs along the first and second guide members, (d) a print head that is mounted on the carriage and prints on print paper, and (e) A transport path formed in a direction perpendicular to the scanning direction and configured to transport the print paper; and (f) a first fixed roller disposed upstream of the print head in the transport path. (G) a first movable roller movably disposed in contact with the first fixed roller, and (h) a second stationary roller disposed downstream of the print head in the transport path. Laura and
(I) a second movable roller movably disposed in contact with the second fixed roller, and (j) connecting one of the first and second movable rollers to the carriage. And a coupling mechanism for rotating the print head in accordance with the movement of one of the first and second movable rollers, and (k) the first and second movable rollers include: A printer device, which is disposed on opposite sides of a print sheet. 2. The printer device according to claim 1, wherein the first movable roller and the second fixed roller are disposed so as to face a surface of the printing paper. 3. The printer device according to claim 1, wherein the first movable roller and the second fixed roller are disposed so as to face a back surface of the printing paper.