JPS59198174A - Paper-feeding mechanism for printer - Google Patents

Abstract

PURPOSE:To facilitate assembling process and enhance the accuracy of positional relationships of a paper-feeding roller, a paper press roller and a paper-supplying guide, by a method wherein a bearing for a paper-feeding roller is fixed by pressing it against a partition wall of a paper-supplying guide by a platen, and a paper press roller is pressed against the paper-feeding roller to pinch a printing paper between them. CONSTITUTION:The bearing 54 for a roller shaft is provided with a projected part 55, a part of the partition wall 48 of a lower guide plate 46 is protruded on the upper side through an opening part of an upper guide plate 47, and the projected part 55 is fitted into a recessed part 56 of the wall 48 from above. The bearing 54 is pressed from above by a lower end surface of a platen 4, and the lower guide plate 46 is pressed from above by the bearing 54. The upper guide plate 47 is also pressed by the platen 4, and the platen 4 is pressed by a frame, thereby completing assemblage of the paper guide 7. The paper-feeding roller 52 and the bearing 54 are fitted and fixed to the partition wall 48 of the guide 7 by the platen 4, and the paper press roller 63 is pressed against the roller 52 to pinch the printing paper between them, so that the positional relationships of the rollers 52, 63 and the guide 7 are maintained to be constant.

Description

[Detailed description of the invention] [Technical field of invention] The present invention relates to a paper feeding mechanism for a printer.

[Technical background of the invention and its problems]

In printers where the paper feed roller and paper presser roller hold the print paper and guide it between the platen and the print head, if the positional relationship between the paper feed roller, paper presser roller, and paper supply guide is not maintained constant, the paper will The feed amount may fluctuate,
There is a risk of meandering. In addition, when installing the paper feed roller in this type of printer, it is common to install roller shaft bearings between the left and right frames and pass the roller shaft between the left and right bearings, but the roller shaft becomes long and assembly is difficult. There are also some difficult problems.

[Purpose of the invention]

The present invention was made based on these circumstances, and
The purpose is to provide a paper feeding mechanism for a printer that is easy to assemble, allows the positional relationship of a paper feeding roller, paper pressing roller, and paper supply guide to be determined with high accuracy, and has a simple configuration.

[Summary of the invention]

A paper feed roller support mechanism for a printer according to the present invention includes a platen, a print head disposed opposite to the platen, and a paper supply having a partition wall for inserting printing paper and regulating movement in the paper width direction. a guide, a roller shaft bearing that is pressed and fixed to the partition wall by the platen, a paper feed roller that is rotatably supported by the roller shaft bearing, and a paper feed roller that feeds the printing paper that is inserted through the paper supply guide. The present invention is characterized by comprising a paper pressing roller which is held between the rollers and guided between the platen and the print head by rotation of the paper feed roller.

With the above configuration, the roller shaft bearing of the paper feed roller is pressed and fixed against the partition wall of the paper supply guide by the platen, and the paper presser is applied to the paper feed roller to sandwich the printing paper between both rollers. Therefore, the positional relationship between the paper pressing roller and the paper supply guide is maintained constant, and assembly is also facilitated. Furthermore, since the roller shaft bearing of the paper feed roller is pressed against the partition wall, there is no need for a long roller shaft that spans between the left and right frames.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

Figure 1 shows the appearance of a printer that prints on rolled receipt paper and journal paper.
are left and right frames, 2 is a paper holder that stores receipt paper and journal paper for supply, 3 is a print head, and 4
5 is the platen, and 5 is the ink ribbon spool 6a, 6b.
ll ink ribbon mounting base, both spools 6a,
The ink ribbon 6 is wound alternately between the ink ribbons 6b.

Further, 7 is a paper supply guide, and 8 is a rotatably mounted stamp mounting plate.

The paper holder 2 is provided with a winding shaft 9 for winding up the printed journal paper. The platen 4 has a ready-made paper guide 1 that guides the journal paper to the winding shaft 9.
0 is provided, and a stamp pad 1 is provided on the side of this guide 10.
1 is integrally formed. Further, a stamp 13 that moves forward and backward while being guided by a stamp guide 12 is attached to the stamp mounting plate 8 so as to face the stamp base 11, and a lever 11 connects the stamp 13 and a cutter (not shown).
An electromagnetic plunger 15 is mounted which is driven via 4.

The print head 3 is attached to a carrier 17 which is slidably attached to a carrier guide shaft 16 as shown in FIG. The left and right frames 1a and 1b include the ink ribbon mounting base 5, the carrier guide shaft 16,
The platen 4 and paper supply guide 7 are integrally connected. The ink ribbon mount 5 connects the front ends of the frames la and 1b. That is, the left and right frames 1a.

1b has four through holes 1 at each front end as shown in Fig. 2.
A pair of through holes 19 are formed in each of the left and right legs of the ink ribbon mount 5. Therefore, when using narrow paper, the through holes 19 of the ink ribbon mount 5 should be placed in the outer through holes 18 of each frame la, 1b, and when using wide paper, the through holes 19 on the ink ribbon mounting base 5 should be placed on the inner through holes 18 of each frame la, 1b. Both are screwed from above in alignment with the through holes 18.

The carrier guide shaft 16 connects the connecting pieces 20 formed at the intermediate portions of the frames 1a and 1b.

That is, the carrier guide shaft 16 has screw holes at both shaft ends. The carrier guide shaft 16 is inserted between the connecting pieces 20 and screwed from the side of the connecting pieces 20, so that the connecting pieces 20 are connected at a predetermined interval. The platen 4 is connected by screwing the bent pieces 21 provided at the rear ends of the frames 1a and 1b from above.

The ink ribbon spool 6 is attached to the ink ribbon mounting base 5.
a, spool stand 22a for loading 6b.

22b and the spool stands 22a, 22b are selectively driven by a fixed amount at a time. A ribbon feeding mechanism 23 is provided. The ribbon feeding mechanism 23 is bent into a mouth shape and connects to the connecting portion 2.
4, and an ink ribbon mounting 6 is made to protrude to the outside of the unit 5.

A carrier drive shaft 25 for reciprocating the carrier 17 along the carrier guide shaft 16 is attached below the carrier guide shaft 16 .

This shaft 25 has an endless groove 26 on its outer periphery, and as shown in FIG. 8, a cam follower 26a provided on the carrier 17 is engaged in this groove 26 to rotate in a fixed direction. The carrier 17 is moved back and forth.

Returning to FIG. 1 again, there is a gear 27 on the outer surface of the frame 1b.
．． 28, 29, eccentric gear 30, etc. are arranged.

The gear 27 is attached to the end of the carrier drive shaft 25, and the rotational force of this gear 27 is transferred to the eccentric gear 3.
0 to gears 28, 29. Further, an electromagnetic plunger 31 is attached to the outer surface of the frame 1b, and an armature 32 that is normally moved by the plunger 31 is engaged with an engagement pin 33 protruding from the eccentric gear 30, so that the eccentric gear 30 is connected to the gear 27. It is held in the disengaged position. The eccentric gear 3o can be brought into mesh with the gear 27 by disengaging the armature 32 from the engagement pin 23 by energizing the plunger 31.

Further, one end of a crank lever 34 is pivotally supported on the gear 28 . As shown in FIGS. 3 to 5, the crank lever 34 has a guide bin 35 and a circular engagement part 36 at the other end, and the guide bin 35 is provided on the side plate of the ink ribbon mount 5. It is slidably fitted into the elongated hole 37, and the circular engaging portion 36 is fitted into the mouth-shaped connecting portion 24 of the ribbon feeding mechanism 23. Then, each time the gear 28 rotates once, the connecting portion 24 is reciprocated once,
The ribbon feeding mechanism 23 is configured to rotate either the spool stand 22a or 22b by one pitch each time the connecting portion 24 rotates, thereby feeding the ink ribbon 6. Note that a guide bin 35 is provided at one end of the elongated hole 37.
A large-diameter hole portion 37a is formed as shown in FIG. 5, into which the
A fitting groove 35a into which both edges of the elongated hole 37 are fitted is formed in the guide bin 35 as shown in FIG.

The carrier drive shaft 25 is the left and right frame 1a.

1b as shown in FIGS. 6 and 7.

That is, each frame 1a, Ib is provided with a fitting recess 38 at a position below the connecting piece 20 so as to open toward the front, and a fitting recess 38 is provided at both ends of the carrier drive shaft 25 to fit into each fitting recess 38. A matching bearing 39 is attached. Roughly, an engagement recess 40 is formed at the opening edge of each fitting recess 38, and a retaining plate 41 is provided which is engaged with the engagement recess 40 of the left and right frames 1a, lb. Therefore, the 6th
As shown in the figure, after fitting the bearings 39 at both ends of the carrier drive shaft 25 into the fitting recesses 38 of the left and right frames 1a, 1b from the front, both ends of the retaining plate 41 are engaged with the engaging recesses 40 of the left and right frames 1a, 1b. By matching the bearing 39 and preventing it from coming off, the bearing 39 can be installed as shown in FIG. Further, a large-diameter gear 42 is attached to the end of the carrier drive shaft 25 opposite to the gear 27, and this large-diameter gear 42 is configured to be rotationally driven by a motor 43 attached to the inside of one frame 1a. It has become.

=9- The ink ribbon mount 5 has a carrier guide 44 bent at a substantially right angle as shown in FIG. 8 at its front edge,
A sliding piece 45 that slides on the carrier guide 44 is attached to the lower end of the carrier 17. Therefore, the carrier 17 is guided by the carrier guide shaft 16 and the carrier guide 44, and reciprocates as the carrier drive shaft 25 rotates.

The paper supply guide 7 is for feeding the receipt paper and journal paper pulled out from the paper holder 2 between the platen 4 and the print head 3, and is provided on the lower guide plate 46 as shown in FIGS. 9 to 11. It is constructed by stacking upper guide plates 47 from above. These guide plates 46.4
7 are all made of synthetic resin and have a convex shape that is concave toward the top, and a gap is formed between both guide plates 46 and 47 that is large enough to allow paper to pass through, and the lower guide plate Partition walls 48 are formed on both sides and in the middle of the upper surface of the partition wall 46 . The intermediate partition wall 48 separates the receipt paper insertion path from the journal paper insertion path. The lower guide plate 48 is screwed to the left and right frames 1a and 1b. In addition, 49 in the figure is a wear prevention body made of a metal plate, and this has three arm parts 50, and these arm parts 50 are attached to the lower guide plate 46.
It is inserted from behind and positioned on the upper surface of each partition wall 48.

In the figure, reference numeral 51 denotes a guide plate made of a thin metal plate, which is attached by being inserted into the front end of the lower guide plate 46, and allows the paper that has passed between the lower guide 46 and the upper guide 47 to pass between the platen 4 and the print head. 3.

In the figure, reference numeral 52 denotes a pair of paper feed rollers, and roller shaft bearings 54 are attached to both ends of the roller shaft 53 of each roller 52. The roller shaft 53 is disposed on the upper surface side of the upper guide plate 47, and each paper feed roller 52 is introduced into the receipt paper insertion path and the journal paper insertion path through an opening provided in the upper guide plate 47. In addition, each bearing 54
has a convex portion 55 as shown in FIGS. 10 and 11, and a part of the partition wall 48 of the lower guide plate 46 protrudes to the upper surface side through an opening provided in the upper guide plate 46. The convex portion 55 is fitted into the formed concave portion 56 from above as shown in FIG. Each bearing 54 is pressed from above by the lower end surface of the platen 4, and the lower guide plate 46 is further pressed from above by the bearing 54. The upper guide plate 47 is also held down by the platen 4 as shown in FIG. 11, and the assembly of the paper guide 7 can be completed by attaching the platen 4 to the frames la and 1b. A ratchet gear 57 is attached to each outer end of the roller shaft 53, and each ratchet gear 57 is connected to a ratchet pawl 5 pivotally supported on the armature 32.
8, the electromagnetic plunger 31 is configured to rotate by one pitch each time the electromagnetic plunger 31 is energized.

As shown in Figure 1, the front. Pulley 5 is for 2 teeth 11tI29.
A belt 61 connects this pulley 59 and a pulley 60 attached to the side wall of the paper holder 2.
I am trying to link it via . Note that inside the paper holder 2 there is a gear (not shown) coaxial with the pulley 60.
A gear 62 attached to the winding shaft 9 is meshed with this gear. Therefore, each time the electromagnetic plunger 31 is energized and the gear 29 rotates in response to the rotational force of the carrier drive shaft 25, the winding shaft 9 rotates by a constant distance.

FIGS. 12 and 13 show the attached state of the pinch roller 63, which presses against the paper feed roller 52 from below. In the figure, reference numeral 64 denotes a pinch roller mounting member having a curved cross-section, and this mounting member 64 has V-shaped image stand portions 65 at both ends. In addition, the left and right frames 1a,
lb is provided with a square hole 66 into which both ends of the mounting member 640 are inserted, and at the lower edge of the square hole 66, a supporting portion is formed with a V-shaped notch at a portion corresponding to each of the V-shaped image matching portions 65. are provided, and as shown in FIG.
By engaging with the mounting members 64, the left and right frames 1a, 1
b is rotatably supported. In addition, the mounting member 6
An operating piece 68 for manual operation is formed upward at one end of the 4, and a set of two locking pieces 69 is formed on the other side where the V-shaped image joining part 65 is not formed. is cut and formed.

Furthermore, an engagement hole 70 located between each set of locking pieces 69 and a set of two stopper protrusions 71 are provided. A pinch roller support plate 72 made of an elastic plate is inserted between each set of locking pieces 69 for installation. Each pinch roller support plate 72 is formed with an engaging piece 73 cut and raised from the lower surface side in the center, and this engaging piece 73 is engaged in the engaging hole 70, and one end is formed by two pieces. It is attached to the attachment member 64 in contact with the stopper protrusion 71 . Further, one support piece 74 extends in parallel from the other end of the pinch roller support plate 72, and both support pieces 74 are configured to support the shaft end of the pinch roller 63 from below. The pinch roller mounting member 64 is urged by two tension springs 75 to rotate in a direction that brings the pinch roller 63 into pressure contact with the paper feed roller 52.

FIG. 14 shows the state in which the stamp mounting plate 8 is attached to the ink ribbon mounting base 5.

14- That is, the stamp mounting plate 8 has left and right pivot pieces 76, and each pivot piece 76 is rotatably supported on the front end portions of the left and right frames 1a and 1b. Furthermore, engagement recesses 77 are formed on the left and right sides of the tip of the stamp mounting plate 8. This engagement recess 77 has a shallower V on the bottom surface of the recess cut out in the shape of a mouth.
It is formed by forming a shaped recess. On the other hand, the left and right frames la.

1b, at the upper end of each of the connecting pieces 20, as shown in FIG.
, (as shown in bl, it has a positioning protrusion 78 that engages with the engagement recess 77, and locking members 79a and 79b made of synthetic resin are screwed to the outer surface of each connecting piece 20. An ink ribbon guide 80 on which the ink ribbon 6 is wrapped is integrally formed with the members 79a and 79b, as shown in FIGS. 15(a) and (t+).

One of the locking members 79a extends upwardly, and the engagement recess 7
A locking stepped portion 81 is provided near the stamp mounting plate 7 from above and reliably inhibits upward rotation of the stamp mounting plate 8. The other locking member 79b is also provided with a locking step 82 near the engagement recess 77 that is hooked from above.
This stepped portion 82 is an inclined surface, and the stamp mounting plate 8
It does not have sufficient retention function for Then, when the upper end of one of the engaging members 79a is opened outward and the locking stepped portion 81 is removed from the stamp mounting plate 8, the holding function for the stamp mounting plate 8 is insufficient with the other locking member 79b alone. ,
The stamp mounting plate 8 can be opened upward. That is, the stamp mounting plate 8 can be easily opened by simply removing one of the locking members 79a.

Next, the operation will be explained.

When rolled receipt paper and journal paper are stored in the paper holder 2 and the leading edge of each paper is inserted between the paper feed roller 52 and the pinch roller 63 and the motor 43 is driven, the carrier drive shaft 25 rotates. Also, the electromagnetic plunger 31 is energized, and the armature 32 is connected to the engagement pin 33.
When released, the eccentric gear 3o meshes with the gear 27 attached to the carrier drive shaft 25, thereby transmitting the rotational force of the carrier drive shaft 25 to the gears 28, 29.

When the electromagnetic plunger 31 is intermittently energized, the ratchet pawl 58 pivoted on the armature 32 feeds the gear 57 one pitch at a time, thereby allowing the receipt paper and journal paper to pass through the paper supply guide 7 and onto the platen. 4 and the print head 3. At this time, the guide plate 51 comes to regulate the traveling direction of the paper. The electromagnetic plunger 31, the armature 32, and the ratchet pawl 58 are provided separately on the outer surfaces of the left and right frames 1a and 1b, making it possible to feed receipt paper and journal paper independently.

When the paper is positioned between the platen 4 and the print head 3, printing can be performed by driving the print head 3. However, for journal paper, first the leading edge of the paper is fixed on the take-up shaft 9. By placing the tape on the winding shaft 9, the winding shaft 9 can be wound up one after another. Regarding receipt paper, each time a single receipt is issued, the electromagnetic plunger 15 is energized, and the cutter operates to separate the paper at an appropriate position.At the same time, the stamp operates 17- to cut the paper at the beginning of the next receipt. Stamp printing will be performed.

Moreover, each time the electromagnetic plunger 31 is energized, the gear 28 is
The ink ribbon 6 rotates, the ribbon feeding mechanism 23 operates, and the ink ribbon 6 is wound one pitch at a time onto one of the ink ribbon spools (for example, 6a). When the ink ribbon 6 is wound up to the end, the ribbon feeding mechanism 23 is switched due to the tension, and the other ink ribbon spool (for example, 6b
) is the winding side.

According to the paper feeding mechanism of the printer configured as described above, the roller shaft bearing 54 of the paper feeding roller 52 is separated from the paper feeding guide 7 by the platen 4! ! ! 48 to fix it, and press the paper press roller (pinch roller 6
3) so that the printing paper is sandwiched between the two rollers 52 and 63, so the paper feed roller 52 and paper presser roller 63
The positional relationship between the paper supply guide 7 and the paper supply guide 7 is kept constant. Furthermore, since the assembly of the paper supply guide 7 and paper feed roller 52 is completed by attaching the platen 4, assembly 18- is also facilitated. Furthermore, the roller shaft 53 does not need to be long enough to span between the left and right frames 1a and lb.

〔Effect of the invention〕

As described above based on the embodiments, according to the present invention, assembly is easy, the positional relationship of the paper feed roller, paper press roller, and paper supply guide can be determined at a height of 1 degree, and the structure is simple. A paper feed mechanism for the printer can be provided.

[Brief explanation of drawings]

The figures show one embodiment of the present invention, in which Fig. 1 is an external perspective view of the printer, Fig. 2 is an exploded perspective view of the main parts of the printer, and Fig. 3 is a perspective view showing the peripheral part of the ribbon feeding mechanism. , FIG. 4 is a partial sectional view showing the crank lever, and FIG. 5 is a side view showing the connecting portion between the crank lever and the ribbon feeding mechanism.
Figure 6 is an exploded perspective view of the area around the carrier drive shaft, Figure 7 is an assembled perspective view of the same area, Figure 8 is a partial sectional view of the area around the carrier, and Figure 9 is an exploded perspective view of the area around the paper supply guide. , 1st
Figure 0 is an exploded side view showing a part of the same part in cross section, No. 11
The figure is an assembled side view of the same part, Figure 12 is an exploded perspective view of the paper presser roller support mechanism, Figure 13 is a side view of the same part, and Figure 14
The figure is a perspective view showing the surrounding area of the stamp mounting plate, and Figure 15 (a
), (b) is a perspective view showing the left and right locking members, No. 16
Figures (a) and (b) are perspective views showing the relationship between the left and right locking members and the stamp mounting plate. 1a, 1b...frame, 4...platen, 7...
・Paper supply guide, 46...lower guide plate, 47...
Upper guide plate, 4... Partition wall, 52... Paper feed roller, 53... Roller shaft, 54... Roller shaft bearing, 5
5...Convex portion, 56...Concave portion, 63...Pinch roller (paper presser roller) Applicant's representative Patent attorney Takehiko Suzue

Claims (3)

[Claims] (1) A platen, a print head disposed opposite to the platen, a paper supply guide having a partition wall for inserting printing paper and regulating its movement in the width direction of the paper, and a number pressed on the partition wall by the platen. A fixed roller shaft bearing, a paper feed roller rotatably supported by the roller shaft bearing, and a printing paper inserted through the paper supply guide is held between the paper feed roller and the paper feed roller by rotation of the paper feed roller. A paper feeding mechanism for a printer, comprising a paper pressing roller that guides the paper between the platen and the print head. (2) The paper supply guide is composed of a lower guide plate and an upper guide plate, the lower guide plate is provided with the partition wall, and both guide plates are integrated by the pressing force of the platen. A paper feeding mechanism for a printer according to claim (1). (3) The partition wall and the roller shaft bearing are stably held by concave-convex fitting.
Paper feeding mechanism of the printer described in section 1).