JPH0416373A - Wire dot printer with horizontal paper passage - Google Patents

Abstract

PURPOSE:To make taking out of jammed paper and cleaning of stained surface on the inside of a device executable by providing a paper passage that is almost horizontal, a fixed frame, a movable frame, a positioning mechanism that positions the movable frame on the fixed frame, and a locking mechanism. CONSTITUTION:A movable frame 4 is mounted on a fixed frame 2 with a connecting member 3 so that the movable frame 4 becomes capable of being swung as well as being fixed. A positioning mechanism 5 and a locking mechanism 6 are provided for determining relative positions of both the frames 2 and 4 so that a horizontal paper passage 7 can be formed when the movable frame 4 is fixed to a specified position on the fixed frame 2. In the case where jamming occurs in the paper passage 7 or the paper passage becomes stained, taking out of the jammed paper or cleaning of the stained surface can be made easily because the structure as mentioned above allows the movable frame 4 to be swung upward with the locking mechanism 6 released.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention includes a wire impact type printing hen,
The present invention relates to a printer with a substantially horizontal paper path, and particularly relates to the arrangement structure of its frame and main components.

(Prior Art) To enable printing on paper that is difficult to bend, such as paperboard, printers are known in which the paper path is formed substantially horizontally.

Printers with linear paper paths have the advantage that paper jams occur less frequently than printers with a structure in which the paper is wound around a platen, but it is still impossible to completely eliminate paper jams. It is. In addition, as printing on sticker paper becomes more frequent, adhesive adheres to the adhesive at the end of the print head and the upper roller of the paper feed roller, which often prevents the paper from passing smoothly. It has become to.

If this kind of paper jam or dirt in the paper path occurs,
Some laser printers, optical reading devices, and the like are in practical use in which the upper frame of the two-part frame is opened to take out paper or to clean the paper path. However, there is no known printer equipped with a wire impact type serial print head that employs this structure. The reason for this is that serial printers developed as an extension of conventional typewriters, so the mainstream structure was to wind the paper around a platen, and instead adopted a structure in which the frame was divided to open the paper path. This was difficult, and wire impact printers needed to maintain a high precision gap between the tip of the print head and the platen. The problem is that it is difficult to guarantee the accuracy of the gap.

(Problem to be solved by the invention) Therefore, in conventional wire impact printers, when a paper jam occurs in the paper path or when cleaning the paper path, the print head and paper feed roller are removed from the frame and the paper is taken out. There was the trouble of having to clean and assemble the parts again, and then reassemble and adjust them.

This invention was made with the aim of avoiding the above-mentioned troubles in wire impact type printers, and is a wire impact type serial printer in which the paper path can be opened and closed while guaranteeing the precision of the headgear between the print head and the platen. The objective is to make the printer practical.

(Means for Solving the Problems) The wire dot printer 1 of the present invention has a movable frame 4 swingably and fixedly provided on a fixed frame 2 by means of a connecting mechanism 3, and a positioning mechanism that fixes the relative positions of both frames 2 and 3. A mechanism 5 and a gate mechanism 6 are provided so that a horizontal paper path 7 is formed when the movable frame 4 is fixed at a predetermined position on the fixed frame 2.

That is, the printer 1 of the present invention has a substantially horizontal paper path 7, a fixed frame 2 and a movable frame 4, a wire impact type Tosomatolinox printing head 42, a ceiling surface 43 of the paper path, and a paper feed roller. A driven roller 41 is provided on the movable frame 4 side, a floor surface 23 of the paper path and a drive roller 21 of the paper feed roller are provided on the fixed frame 2 side,
The movable frame 4 is supported to be rotatable upward on a support shaft 36 parallel to the running direction of the print head 42 and to be minutely adjustable in position within a plane parallel to the paper path 7, thereby positioning the movable frame 4 to the fixed frame 2. Positioning pair 51.53 or 55
．． 56 is provided.

The positioning pair 51.53 or 55.56 may be provided with a tapered surface 51a, 53a or 55a that guides the movable frame 4 to a stable position in the paper feeding direction and the paper width direction, and the locking mechanism 6 may include: A structure may be adopted in which wedge surfaces 64 for pushing the movable frame 4 downward are provided on both sides in the sheet width direction at positions close to the positioning pair.

(Function) In the wire dot printer having the above structure, when a paper jam occurs in the paper path 7 or the paper path becomes dirty, the locking mechanism 6 is released and the movable frame 4 is opened upward to take out the paper or clean the dirty surface. Cleaning can be done easily.

In the structure of the present invention, when the open movable frame 4 is closed, the relative three-dimensional positioning of the movable frame 4 and the fixed frame 2 (up, down, front, back, left, and right) is performed by the positioning pair 5.
1.53 or 55.56, so
The positional relationships between the print head and the platen, and between the drive roller 21 and the driven roller 41 of the paper feed roller are reproduced with high precision.

Moreover, in this invention, the reproducibility of the positional accuracy is not dependent on the accuracy of the support shaft 36 that pivotally supports the movable frame 4 (but on the processing and assembly accuracy of the positioning pair 51.53 or 55.56, which has a simple structure). Therefore, higher positioning accuracy can be achieved at a lower cost.

(Embodiment) FIGS. 1 to 6 show a first embodiment of the present invention. The printer 1 of the present invention has a movable frame 4 swingably and fixedly provided on a fixed frame 2 by a connecting mechanism 3, and includes a positioning mechanism 5 and a locking mechanism 6 for fixing the relative positions of both frames 2.4. A paper path 7 is formed when the movable frame 4 is fixed at a predetermined position on the fixed frame.

As shown in FIGS. 1 and 2, drive rollers 21 for two paper feed rollers arranged in the paper path 7 are disposed on the upper part of the fixed frame 2, and a platen is located between the two drive rollers. 22 is fixed.

A lower guide 23 that forms the floor of the paper path is fixed between the drive roller 21 and platen 22 on the paper feed side and between the drive roller 21 and platen 22 on the paper discharge side. The movable frame 4 is provided with a driven roller 41 that comes into contact with the drive roller 21 when closed, and a print head 42 that faces the platen 22.
An upper guide 43 forming a ceiling surface of the paper path is identified between the driven roller 41 on the paper ejection side and the platen 22. The movable frame 4 is urged in the opening direction by a compression spring 24 fixed to the fixed frame.

FIG. 3 shows a connecting mechanism 3 that pivotally connects the movable frame 4 to the fixed frame 2. The coupling mechanism 3 has a circular structure in which the upper end of the fixed frame 2 is bent inward to form a receiver vi, 31 behind the drive roller on the paper ejection side (on the left side in FIG. 1), and a horizontal surface 32 is formed on the lower surface of both ends. A through hole 34 perpendicular to the horizontal surface of the rod 33 is bored, and the stepped surface at the far end of the horizontal surface 32 is fitted between the tips of the receiving plate 31 and fixed with bolts 35 to form a support shaft 36. It has a structure in which a bracket 37 is fitted onto a support shaft 36 so as to be rotatable and movable in the axial direction, and the bracket is fixed to the movable frame 4. Holt 35 has through hole 34
Due to the smaller diameter and the gap between them, the support shaft 36 can be adjusted by minute movements within the plane of the plate 31.

The positioning mechanism is shown in Figures 1.2 and 4. Vm51 is provided on the upper edges of both side walls of the fixed frame 2, and a positioning bar 52 having a circumferential groove 53 with a V-shaped cross section is installed on the movable frame 4 side at a position facing Va51. When the movable frame 4 is rotated around the support shaft 36 and lowered, the tapered surface 51a of the groove 51 and the tapered surface 53a of the circumferential groove 53 come into contact with each other to move the movable frame 2 in a stable direction. . Finally, ■Groove 51 and Circumferential groove 5
3 are fitted, and the horizontal relative position of the movable frame 4 with respect to the fixed frame 2 is determined.

Two pairs of the V groove 51 and the circumferential groove 53 are provided on the left and right to regulate the relative position of the fixed frame 2 and the movable frame 4, so when these are fitted, the support shaft 36 is connected to the fixed frame with the port 35. 2.

A locking mechanism 6 is also shown in FIG. 1.2.4, and the locking mechanism 6 is provided with a swingable hook 62 on a pin 61 implanted in the fixed frame 2. A guide surface 63 is formed at the upper end of the hook, and a wedge surface 64 is provided below the guide surface 63. The flap 62 is held in a swingable upright state by a winding spring 65 fitted to a pin 61. When the movable frame 4 descends, the locking pin 66 implanted in the movable frame 4 comes into contact with the guide surface 63 of the hook, causing the hook 62 to rotate as shown in FIG. 66 is engaged by the wedge surface 64, and the fixed frame 2 and movable frame 4 are positioned in the vertical direction. The wedge surface 64 pushes the locking pin 66 downward by a wedge action when the member rotates as shown in FIG. 1 due to the urging force of the winding spring 65.
The fixed frame 2 and the movable frame 4 are fastened together with the groove 51 and the circumferential groove 53 strongly pressed together.

FIG. 5 is a sectional view of the platen, in which the surface facing the printing head 42 is a cylindrical surface with a convex center. In this way, by making the surface of the platen 22 a slightly convex cylindrical surface, even if the relative position or horizontality of the upper frame 4 and lower frame 2 is slightly incorrect, the deterioration in print quality due to the deviation can be minimized. It can be suppressed.

FIG. 6 is a plan view of the driven roller mounted on the movable frame 4. FIG. A pivot shaft 44 is installed on the movable frame 4, a link 45 is pivotally supported at both ends of the pivot shaft, a roller shaft 46 is rotatably installed at the tip of the link, and the roller shaft is divided into a plurality of parts. The driven roller 41 is formed by fixing the roller elements. The roller shaft 46 has a pivot 4
The tips of a plurality of arms 47 swingably disposed on the roller 4 are in contact with each other from above, and each arm is provided with a winding spring 48 to urge the roller shaft 46 downward. Each roller element of the driven roller 41 is biased toward the drive roller 21 in a magnitude corresponding to the biasing force of the arm 47 closest to it. 4A is a pin implanted in the side surface of the link 45, and 4B is a stopper implanted in the pivot shaft 44, which rotates the pivot shaft 44 to separate the driven roller 41 from the drive roller 21.

7 to 9 show a second embodiment of the present invention. In this embodiment, the platen 22 is fixed to the movable frame 4 side, and two positioning pins 55 with conical tips are provided on the bottom surface of the platen 22, and a positioning hole 57 in which the positioning pins 55 fit into the fixed frame 2 is provided. A positioning plate 56 having a long hole 58 is provided, and when the movable frame 4 is moved down, the conical surface 55a of the positioning pin 55 of the platen 22 is fitted into the positioning hole 57 and the long hole 58, and the movable frame 4 is placed in a stable position. Both frames 2.4 are fixed by a locking mechanism 6 similar to the first embodiment. The elongated hole 58 is long in the running direction of the print head 42, and the positioning pin 55 and the circular hole 57 define one point, and the positioning pin 55 and the elongated hole 58 define an angle around that point, thereby positioning the upper and lower frames. The positions of the upper and lower frames in the height direction are defined by the contact between the stepped portion at the base end of the positioning pin 55 and the upper surface of the positioning plate 56. The structure other than the above is the same as that of the first embodiment.

(Effects of the Invention) As described above, in the wire dot printer of the present invention, when a paper jam occurs in the paper path or the paper path becomes dirty, the locking mechanism is released and the movable frame is opened upward to take out the paper. In addition, when the open movable frame is closed, the relationship between the print head, the platen, and the drive roller and driven roller of the paper feed roller can be reproduced with high precision. Further, since the reproducibility of positional accuracy is made to depend on the machining and assembly accuracy of the positioning pair, which has a simple structure, rather than on the accuracy of the spindle that pivots the movable frame, higher positioning accuracy can be achieved at a lower cost.

Therefore, it is possible to provide a wire-impact type serial printer that can open and close the paper path while guaranteeing the hand-gassing accuracy between the print head and the platen.

[Brief explanation of drawings]

1 to 6 are diagrams showing a first embodiment of the present invention, in which FIG. 1 is a schematic side view of the entire device, and FIG. 2 is a schematic side view of the entire device when the movable frame is opened. Side view, 3rd
4 is a front view showing details of the positioning portion of the fixed frame and movable frame; FIG. 5 is a detailed view showing the cross-sectional shape of the platen; FIG. 6 is a plan view showing the detailed structure of the driven roller. 7 to 9 are views showing the second embodiment, in which FIG. 7 is a schematic side view of the entire device, and FIG. 8 is a schematic side view of the entire device when the movable frame is opened. FIG. 9 is a front view showing details of the positioning portions of the fixed frame and the movable frame. In the figure, 2: Fixed frame 4: Movable frame 6: Lock mechanism 7 = Paper path 21: Drive roller 22 of the paper feed roller 22 Nibraten 23: Floor surface of the paper path 36: Support shaft 41: Driven roller 42 of the paper feed roller: Print head 43: Ceiling surface of paper path 48: Winding blade 53: Positioning pair 1a 53a: Tapered surface 56: Positioning pair 55a: Tapered surface 64: Wedge surface

Claims (4)

[Claims] (1) Has a substantially horizontal paper path (7), and has a fixed frame (
2) and a movable frame (4), a wire impact type dot matrix printing head (42), a paper path ceiling surface (43), and a paper feed roller driven roller (41) are provided on the movable frame side. The floor of the passageway (23) and the drive roller (21) of the paper feed roller are provided on the fixed frame side, and the movable frame (4) rotates upward on a support shaft (36) parallel to the running direction of the print head (42). movable and supported so as to allow minute position adjustment in a plane parallel to the paper path (7);
A positioning pair (51, 53) or (55, 56) for positioning the movable frame (4) to the fixed frame (2) at positions on both sides in the paper width direction and a locking mechanism (6) are provided. wire dot printer. (2) The above positioning pair (51, 53) or (55, 56
) is a movable frame (4) in the paper feed direction and paper width direction.
tapered surfaces (51a, 53a) or (55a) that guide the movable frame (4) to a stable position, and wedge surfaces (64) that push the movable frame (4) downward on both sides in the paper width direction at a position close to the positioning pair. 2. Wire dot printer according to claim 1, characterized in that a locking mechanism (6) with a locking mechanism (6) is provided. (3) The surface of the platen (22) facing the print head (42) is a medium convex cylindrical surface curved in the paper feeding direction, and the platen (22) is mounted on the fixed frame (2). Wire dot printer as described. (4) The driven roller (41) of the paper feed roller is composed of a plurality of roller elements divided in the paper width direction, and a spring (48) urges each roller element individually toward the drive roller (21) side. The wire dot printer according to claim 1, further comprising a wire dot printer.