JPH11179997A - Impact printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a impact wire dot-matrix printer that prevents stains arising from printed ink from being produced on the surface of printing paper. SOLUTION: An impact printer is equipped with an impact print head 22 having a leg part 50 being opposite to printing paper 33, a carrier 23 for supporting a gap regulating roller 29 that regulates a gap between the leg part 50 and the printing paper 33, a ribbon feeding device for feeding an ink ribbon 57 through the gap, and a means that moves the carrier 23 so that the leg part 50 of the impact print head 22 is moved along a printing passage perpendicular against the line feeding direction of the printing paper, and the gap regulating roller 29 is mounted, adjoining the leg part 50 of the impact print head 22, at a position closer to the upstream side than the leg part 50 of the impact print head 22 in the line feeding direction of the printing paper 33.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cut printing sheet called a single cut form, or a printing sheet called a multi form in which a plurality of sheets are overlapped with each other, or a diary, book, passport, The present invention relates to a shock type wire dot matrix printer for printing a book type print document such as a bank passbook using a shock type wire dot print head having a plurality of print wires. Printing paper called multi-form is printing paper on which a plurality of pressure-sensitive papers are stacked or paper on which carbon for transfer is attached on the back side.

More specifically, the present invention relates to an impact type wire dot matrix printer which prevents the surface of a printing paper from being stained by printed ink.

[0003]

FIG. 1 shows an arrangement of a platen 1 and a shock type wire dot print head 2 of a conventional shock type printer. Two guide rods 4 extend in a direction perpendicular to the plane of FIG. A carrier 3 is slidably mounted on a guide rod 4 and is moved in a direction perpendicular to the plane of the paper.
The carrier 3 is moved up and down in the direction of arrow 18. Mounting portions 5 extending from both sides of the print head 2 are fixed to the carrier 3 by screws 6, respectively. The legs 17 of the print head 2 include a plurality of print wires 8 and these are the carrier 3 and the print head 2.
Is selectively energized when is moved in a direction perpendicular to the paper surface, and prints dots representing characters on the printing paper 13. A gap defining roller 9 made of a rigid material such as, for example, steel, nylon, Teflon, polyacetal,
It is mounted on the carrier 3 by studs or spacers 12 and screws 11. The opening of the carrier 3 through which the screw 11 passes is an elongated slot extending in the direction of the arrow 18 for adjusting the gap G. The gap defining roller 9 includes a bearing 16. The gap defining roller 9 is mounted on the carrier 3 so as to define a gap G of, for example, 0.25 mm to 0.3 mm between the bottom surface of the print head 2 and the surface of the printing paper 13. Print wire 8
Are selectively projected from the bottom surface of the print head 2 toward the printing paper 13 via the gap G. Print·
Ink ribbon 1 between bottom surface of head 2 and printing paper 13
4 is fed.

[0004]

To explain the operation of this conventional printer, the printing paper 13 is fed in the direction of arrow 15 from the front side to the rear side of the printer, and prints the first print line. To be stopped. During the printing of the first print row, the carrier 3 and the print head 2 are moved in a direction perpendicular to the plane of the paper, and the wet ink of the ink ribbon 14 is transferred to the printing paper 13. After the printing of the first print line is completed, the printing paper 13 is fed by one line in the direction of the arrow 15 (this is called a line feeding operation), and the carrier 3 and the print head 2 are again perpendicular to the paper surface. To print the second print line. The problem that arises during the printing of this second row is that the gap defining roller 9 rolls over the wet ink that has just been transferred to the first printing row, this wet ink is transferred to the gap defining roller 9, and the gap While the regulating roller 9 rolls on the printing paper 13, the wet ink is transferred to the printing paper again,
As a result, as shown by the printing result of the conventional printer in FIG. 5B, the printing paper 13 is stained by the transferred ink. This problem is
This occurs because the gap defining roller 9 is disposed behind the leg 17 of the head 2.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an impact type wire dot matrix matrix which solves the above-mentioned problems.
It is to provide a printer.

An impact printer according to the present invention comprises an impact print head having a leg facing a print sheet, a carrier supporting a gap defining roller defining a gap between the leg and the print sheet, and a carrier in the gap. A ribbon feeder for feeding the ink ribbon, and means for moving the carrier to move the legs of the impact print head along a print path perpendicular to the line feed direction of the printing paper; A gap defining roller is mounted adjacent to the leg of the impact print head and upstream from the leg of the impact print head as viewed in the line feed direction of the printing paper.

[0007] The gap defining roller has an outer rubber tire.

The leg portion has a bottom surface facing the printing paper, and a portion of the bottom surface that forms a right corner together with the right side wall of the leg portion is a right corner in a direction perpendicular to the printing paper and an outer surface of the outer rubber tire. Characterized by being inclined so as to increase the distance between them.

[0009] The portion of the bottom surface that forms the left corner with the left side wall of the leg is inclined to increase the distance between the left corner and the outer surface of the outer rubber tire in a direction perpendicular to the printing paper. It is characterized by the following.

An impact type printer according to the present invention includes an impact type print head having a leg facing a print sheet, a carrier supporting a gap defining roller defining a gap between the leg and the print sheet, and a carrier for the gap. A ribbon feeder for feeding the ink ribbon; means for moving the carrier to move the legs of the impact print head along a print path perpendicular to the line feed direction of the printing paper; A feed roller positioned downstream of the leg in the feed direction, the leg of the impact print head adjacent to the leg of the impact print head and viewed in the line feed direction of the printing paper. A gap defining roller is mounted at a position upstream of the section, and the distance between the printing position below the leg of the impact print head and the feed roller is:
The ink is transferred at a printing position from the ink ribbon, and is selected such that the ink dries before reaching the feeding roller.

[0011]

FIG. 2 shows an impact dot matrix printer according to the invention for preventing the printing paper from being stained by the transferred wet ink. Two support frames 25 and 26 are fixed to the upper surface of the frame 21 of the printer. A first arm support device and a second arm support device are pivotally attached to support frames 25 and 26. The first arm support device includes support arms 27 and 30 and is pivotally connected to support frames 25 and 26 at pivot points 37 and 35, respectively. The second arm support includes support arms 28 and 31 and is pivotally connected to support frames 25 and 26 at pivot points 38 and 36, respectively. Two guide rods 24 are supported by support arms 27, 30, 28 and 31.

The carrier 23 is slidably mounted on two guide rods 24. An impact-type wire dot print head 22 and a gap defining roller 29 arranged according to the present invention are mounted on a carrier 23. The detailed arrangement of the carrier 23, the print head 22, and the gap defining roller 29 will be described later with reference to FIG.
The part behind the support arm 31 is moved in the direction of the arrow 41 or the direction of the arrow 42 by the driving device 39. A plurality of print wires, such as twenty-four, are arranged on the bottom surface of print head 22 in a direction perpendicular to print path 40, i.e., in the directions of arrows 43 and 44. Pivot point 37 (35), pivot point 38 (36) and two guide rods 2
4 constitutes each vertex of the parallelogram. Therefore, the rear portion of the support arm 31 is moved by the drive device 39 to the arrow 41 or
, The bottom surface of the print head 22 is moved in the ascending or descending direction with respect to the printing paper 33. During this movement of the print head 22 and while landing on the print sheet 33, the plurality of print wires are always in a direction perpendicular to the surface of the print sheet 33 and to a platen located in the print path 40. Be aligned.

This printer operates as follows. In the standby state, the drive unit 39 gives the direction of the driving force of the arrow 42, thereby the print head 22 is standby position separated by a gap G _A from the surface 45 of the printing paper 33 as shown in FIG. 3 Moved to Next, the printing paper 33
Is fed in the direction of arrow 43. The printing paper 33 is a cut printing paper called a single cut form, or a multi-cut printing paper in which a plurality of printing papers are stacked on each other.
This is printing paper called a form. The multi-form is a printing paper on which a plurality of pressure-sensitive papers are stacked or a paper on which a plurality of papers with carbon for transfer attached to the back side are stacked. Printing paper 3 in the direction of arrow 43 or 44
3 is not shown in FIG. 4 because it is well known in the art. When the first printing line of the printing paper 33 is aligned with the printing path 40, the driving device 39 moves to the arrow 41.
In the direction of the print head 2
The second gap defining roller 29 is disposed on the surface 45 of the printing paper 33.
To land. During the printing operation, the gap defining roller 29 is pressed against the printing paper 33 based on the biasing force of springs (not shown) attached to the first and second arm supporting devices and the weight of these devices. In this state, for example,. A gap G, such as between 0.25 mm and 0.3 mm, is maintained between the bottom surface of the print head 22 and the surface 45 of the printing paper 33.

When the print head 22 is moved along the print path 40 by a carrier driving device (not shown), the gap defining roller 29 causes the surface 45 of the printing paper 33 to move.
, Whereby the gap G is maintained at a constant value and a constant print quality is obtained. As the print head 22 is energized during the movement, a print wire is protruded across the gap G to transfer ink from the ink ribbon to the printing paper 33. When a multi-form is used, the print content of the uppermost sheet is copied to the lower print sheet.

When the printing of one print line is completed, the driving device 39 applies a driving force in the direction of arrow 42, so that the print head 22 is separated from the surface 45 of the printing paper 33 by the gap G _A. Moved to the position. After the print sheet 33 has been fed by one line, the print head 22 is landed on the surface 45 of the print sheet 33 and the printing operation is performed. When all the print lines have been printed,
The print head 22 is raised to the standby position, and the printing paper 33 is ejected by feeding it in the direction of arrow 44.

FIGS. 4A and 4B are a front view and a side view of the arrangement of the impact type wire dot print head 22 and the gap defining roller 29 according to the present invention. The carrier 23 has three protrusions 6 through which two guide rods 24 pass.
2 are provided. The two mounting portions 63 for mounting the print head 22 to the carrier 23 are the print 2
2 are extended from both sides. Gap defining roller 29
The support plate 56 for attaching the print head 2
The gap defining roller 29 is mounted on the carrier 23 at a position adjacent to the second leg 50 and upstream of the leg 50 of the print head 22 when viewed in the line feed direction 43 of the printing paper 33. Have been. Printing paper 33
In a printer in which the line feeding operation for printing on the printer is performed in the direction of arrow 43 from the front side to the rear side of the printer, the gap defining roller 29 is connected to the print head 2.
It is attached to the front side of the second leg 50. To this end, for each mounting portion 63, a stud or spacer 55
At the carrier 23. The screw 53 is fixed to the stud 55 through an opening in the support plate 56, and the screw 54 is fixed to the stud 55 through an opening in the carrier 23 and an opening in the mounting portion 63. The bottom surface of the leg 50 from which the print wire 52 protrudes is positioned at the gap G from the lower end of the gap defining roller 29, that is, the surface of the printing paper 33.
For example, they are separated by 0.25 mm to 0.3 mm. The opening of the support plate 56 through which the screw 53 passes is an elongated slot extending in a direction perpendicular to the surface of the platen 51 in order to adjust the gap G. Gap G shown in FIG.
Is shown enlarged to clearly show the ink ribbon 57 in this gap G.
The ink supplied from the ink ribbon cartridge
The ribbon 57 is arranged between the bottom surface of the leg 50 and the printing paper 33. Ink ribbon cartridges are well known in the art and are not shown for simplicity.

The gap defining roller 29 according to the present invention comprises:
It has an outer rubber tire 60 and a bearing 59. The function and effect of the outer rubber tire 60 will be described later.

The effect of the above arrangement of the gap defining roller 29 and the leg 50 of the print head 22 according to the present invention is as follows. The positions of the print head 22 and the gap defining roller 29 shown in FIGS. 4A and 4B are determined by the driving device 39 shown in FIG. This is the position where the paper has landed. As shown in FIG.
The printing paper 33 is fed in the line feeding direction 43 by a paper feeding mechanism including the paper feeding rollers 64 and 65, and the first printing line # 1 of the printing paper 33 is positioned below the leg 50 of the print head 22. When aligned, the carrier 23 and print head 22 are moved on the guide bar 24 in a direction perpendicular to the plane of FIG. 4 (B), and the printing operation of the first print line # 1 is performed. . When the first print line # 1 has been printed, the guide rod 24, the carrier 23, the print head 22
And a gap defined roller 29, the direction of the drive force of the arrow 42 exerted by the drive unit 39 is raised to just released the standby position gap G _A in FIG. 3, and the printing paper 33, the legs of the next print line The paper is fed by a paper feeding mechanism by a predetermined distance to be positioned below the bottom surface of 50. When the second print line # 2 of the printing paper 33 is aligned under the leg 50 of the print head 22, the driving device 39 applies a driving force in the direction of the arrow 41 so that the gap defining roller 29 causes the printing paper , And the printing of the second print line # 2 is performed. Leg 5 of print head 22
0, and the gap defining roller 29 is mounted only at a position upstream of the leg 50 of the print head 22 when viewed in the line feeding direction 43 of the printing paper 33, and a gap is provided at a position downstream thereof. Obviously, since the defining roller 29 is not present, the gap defining roller 29 never contacts the transfer ink of the first print line # 1 and the subsequent print line # 2. Then, the printing position of the lower side of the leg 50 of the print head 22 and the leg 5 as viewed in the line feeding direction.
The distance between the paper feed rollers 64 and 65 disposed downstream of the ink ribbon 57 at the printing position.
The wet ink transferred from the paper feed rollers 64 and 65 is selected to dry sufficiently before it reaches the feed rollers 64 and 65, thereby preventing the transfer of the ink to these paper feed rollers 64 and 65, and The contamination of the printing paper due to the presence of the paper feeding rollers 64 and 65 is prevented. FIG. 5A shows a print result printed by the printer according to the present invention. The print result of FIG.
Comparing with the print result printed by the conventional printer shown in FIG. 5B, the print result shown in FIG. 5A shows that the printing paper is completely prevented from being stained by the wet ink. Is evident.

As described above, the outer rubber tire 60 is mounted on the gap defining roller 29 of the present invention. In the arrangement according to the present invention shown in FIGS. 4A and 4B, a rubber roller to which ink easily adheres is used as the outer roller 60 because the printing paper 33 is completely prevented from being stained by the wet ink. It became possible. As described above, the gap defining roller 29 is pressed against the printing paper 33 by the biasing force applied by the springs attached to the first and second arm supporting devices and the weight of these arm supporting devices during the printing operation. Thereby, the outer rubber tire 60 is pressed against the printing paper 33, and the contact area of the outer rubber tire 60 increases.
The effect of the increase in the contact area realized by the use of the outer rubber tire 60 is as follows. (1) Since the pressure per unit area is reduced, color formation when using pressure-sensitive paper is prevented; (2) The sliding operation (i.e., deviation) of the stacked printing papers caused by the drag force (drag force) based on the rotational movement of the gap defining roller 29 is significantly reduced. To explain the sliding operation, when a roller having a small contact area rotates and runs on a stacked sheet, the stacked sheet slides gradually in the direction of the roller movement, and the amount of sliding is the most. It gradually decreases from the top sheet to the bottom sheet. The present invention allows for the use of outer rubber tires 60 with a large contact area so that the sliding motion of stacked printing papers or multi-forms can be reduced, and the sliding motion on each paper based on this sliding motion is reduced. The displacement of the printing position can be significantly reduced.

The printer of the present invention can print characters on the left and right pages of a book-type print document such as a diary, book, passport, bank passbook, and the like. When printing a book-type print document such as a passport, the passport is opened and the right and left pages are exposed to the print head 22 as shown in FIG. In the passage 73 of FIG. 6, the print head 22 mounted on the carrier 23 is driven by a carrier driving device (not shown).
Represents a guide rod 24 that is reciprocated. Position P _L is the leftmost or home position of the leg 50 of the print head 22 on the guide bar 24 and position P _R is the rightmost position of the leg 50 of the print head 22.

FIG. 7A shows that the rightmost corner 67 on the bottom surface of the leg 50 of the print head 22 makes undesirable contact with the top sheet when a passport is printed. Indicates a problem. A ribbon cartridge having lower portions 74 and 75 is secured to carrier 23. The surface of the lower portion 74 is rounded to smoothly ride on the left edge of the left page of the passport as the carrier 23 is moved from the home position P _{L in} the direction of arrow 76. . Lower part 75
Has also been rounded for bidirectional printing.
FIG. 7A shows a state in which the lower part 74 has just landed on the page on the left side of the passport 72. In a conventional printer, the right corner 67 on the bottom surface of the leg 50 of the print head 22 is used.
And the left corner 68 is a distance D from the outer surface of the gap defining roller 29 in a direction perpendicular to the platen or sheet surface.
_It protrudes by _one so that the top sheet of the left page of the passport engages the right corner 67, causing the edge of the top sheet to be damaged or slipping. Such an undesired problem also occurs when the leg 50 crosses the boundary between the lower left page and the higher right page as shown in FIG.

FIG. 7B illustrates the leg 5 of the print head 22 according to the present invention which solves the above-mentioned undesirable problems.
0 shows the structure of the bottom surface 66. Right side wall 70 of bottom surface 66
As part 66A forming a right corner 67, perpendicular to the surface of the printing paper 33 to increase the distance D ₂ between the corner 67 and the gap defined roller 29 in the direction along with,
The print head 22 is tilted with respect to the bottom surface 66 parallel to the platen, as shown in FIG.
Undesirable engagement of the corners 67 of the legs 50 of the upper sheet with the uppermost sheet is completely prevented, and the legs 50 are
(A) When passing through the boundary between the right page and the left page of the passport 72, it is completely prevented from engaging with the right page having a high height.

As described above, the corner 68 and the gap defining roller 2 in the direction perpendicular to the surface of the printing paper 33 are
In order to increase the distance from the outer periphery of the base 9, a portion 66 B of the bottom 66 that forms a corner 68 with the left side wall 71 is inclined with respect to the bottom 66 parallel to the platen, whereby the printing operation is performed at the position P. _This is performed from _R to the position P _L , and as shown in FIG. 6B, the leg 50 is reliably passed when the height of the left page is higher than that of the right page.

[0024]

According to the present invention, the printing paper is completely prevented from being stained by the wet ink, the undesired coloring of the stacked pressure-sensitive paper is significantly reduced, and the gap defining roller 29 is provided.
The sliding movement of the stacked sheets is significantly reduced, and the impact-type wire dot matrix matrix allows the print head to reliably ride up and pass over the top sheet of a book-type printed document. Implement a printer.

[Brief description of the drawings]

FIG. 1 is a diagram showing an arrangement of a print head and a gap defining roller of a conventional printer.

FIG. 2 shows a printer according to the invention.

FIG. 3 is a diagram showing a gap between a bottom surface of a print head and a front surface of a printing sheet.

FIG. 4 is a diagram showing a configuration of a print head and a gap defining roller according to the present invention.

FIG. 5 is a diagram showing print results by a printer according to the present invention and a conventional printer.

FIG. 6 is a diagram illustrating an operation of printing a passport.

FIG. 7 is a diagram showing the structure of the bottom surface of a conventional print head and the print head of the present invention.

[Explanation of symbols]

 Reference numeral 22 Print head 23 Carrier 24 Guide rod 29 Gap defining roller 33 Printing paper 50 Leg 51 Platen 55 Stud 56・ Support plate 57 ・ ・ ・ Ink ribbon 60 ・ ・ ・ Outer rubber tires 64, 65 ・ ・ ・ Paper feeding roller 66 ・ ・ ・ Bottom surface 67 ・ ・ ・ Front corner 68 ・ ・ ・ Rear corner 70, 71 ・..Side walls

Claims (8)

[Claims] An impact print head having a leg facing a printing sheet, a carrier supporting a gap defining roller defining a gap between the leg and the printing sheet, and an ink ribbon in the gap. And a means for moving the carrier to move the leg of the impact print head along a printing path perpendicular to the line feeding direction of the printing paper. The gap defining roller is mounted at a position adjacent to the leg of the impact print head and upstream from the leg of the impact print head as viewed in the line feeding direction of the printing paper. A shock type printer characterized by the following. 2. The impact type printer according to claim 1, wherein said gap defining roller has an outer rubber tire. 3. The leg portion has a bottom surface facing the printing paper, and a portion of the bottom surface that forms a right corner together with a right side wall of the leg portion is the right corner in a direction perpendicular to the printing paper. 3. The impact-type printer according to claim 2, wherein the impact type printer is inclined so as to increase the distance between the outer rubber tire and the outer surface of the tire. 4. A portion of the bottom surface forming a left corner together with the left side wall of the leg portion increases a distance between the left corner and the outer surface of the outer rubber tire in a direction perpendicular to the printing paper. 4. The impact-type printer according to claim 3, wherein the impact-type printer is inclined. 5. An impact print head having a leg facing a printing paper, a carrier supporting a gap defining roller defining a gap between the leg and the printing paper, and an ink ribbon in the gap. And a means for moving the carrier to move legs of the impact print head along a print path perpendicular to a line feeding direction of the printing paper; and A feed roller disposed downstream of the leg when viewed in the feed direction, the roller being adjacent to the leg of the impact print head and viewed in the line feed direction of the printing paper. The gap defining roller is mounted at a position upstream of the leg of the mold print head, and the impact type print head is mounted.
The distance between the print position below the head leg and the feed roller is selected as the distance at which the ink transferred from the ink ribbon at the print position dries before reaching the feed roller. An impact type printer characterized by being performed. 6. The impact type printer according to claim 5, wherein said gap defining roller has an outer rubber tire. 7. The leg portion has a bottom surface facing the printing paper, and a portion of the bottom surface that forms a right corner together with a right side wall of the leg portion is the right corner in a direction perpendicular to the printing paper. 7. The impact type printer according to claim 6, wherein the printer is inclined so as to increase a distance between the outer rubber tire and an outer surface of the outer rubber tire. 8. A portion of the bottom surface forming a left corner together with the left side wall of the leg portion increases a distance between the left corner and the outer surface of the outer rubber tire in a direction perpendicular to the printing paper. The impact type printer according to claim 7, wherein the impact type printer is inclined.