JPS60232981A - Printer - Google Patents

Abstract

PURPOSE:To enhance reliability of a printer and contrive a higher speed, a lighter weight and a lower cost, by reducing the number of fixing and unfixing means such as solenoids which are provided. CONSTITUTION:Before a driving wheel 6 corresponding to a digit place is engaged to a trigger plate 11, a pulse signal is outputted from a digit place detector 42, and an electric current is passed to one or all of the solenoids 2a-2d correspondingly to a character to be printed at the digit place. Soon after passing the current, a driving pawl 38 of the driving wheel 6 corresponding to the digit place is engaged to a trigger projection 18 of the trigger plate 11, the plate 11 is rotated in the direction opposite to the direction of an arrow (a) against the elasticity of a tension spring 28 by a rotating force of a driving wheel shaft 37, and the first-fourth selecting plates 12-15 are also rotated together in the same direction, whereby a pawl part 29a of the first selecting plate 12 is engaged to a tooth part 41 of a movable plate 4a, a pawl part 29b of the second selecting plate 13 is engaged to a tooth part 41 of a movable plate 4b, a pawl part 29c of the third selecting plate 14 is engaged to a tooth part 41 of a movable plate 4c, and a pawl part 29d of the fourth selecting plate 15 is engaged to a tooth part 41 of a movable plate 4d.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a printer, and particularly to a printer in which a plurality of type shafts are arranged side by side in the digit direction.

[Background of the invention]

In conventional printers in which a plurality of type shafts are arranged side by side in the digit direction, an electromagnetic solenoid is installed for each type type shaft. Then, during one rotation of the type shaft, the type selection for each type shaft is made.
In synchronization with this, the electromagnetic solenoid attached to the type shaft is energized, which activates the ratchet mechanism.
Maintains the rotational position of the type shaft. In this way, after all digits, that is, all type axes, are selected, the platen roller is pressed against the selected type area via the ink ribbon and printing paper to print on the paper, and after printing, the reset lever is pressed. It rotates to reset the ratchet mechanism.

In a printer with this configuration, for example, in the case of an 18-digit printer, it is necessary to arrange 18 electromagnetic solenoids. Therefore, when printing the same typeface (symbol) over all digits, 18 electromagnetic solenoids must be energized at once, which not only extremely increases power consumption but also causes malfunctions. Furthermore, since 18 electromagnetic solenoids are installed, the entire printer becomes larger and heavier. Furthermore, the number of commonly used electromagnetic solenoids is about 100.
It has a relatively high resistance value of ~300Ω, and due to space considerations, a thin coil is used as the excitation coil, especially when all electromagnetic solenoids are energized at the same time as mentioned above. it runs slower,
This will interfere with speeding up.

[Purpose of the invention]

The purpose of Honkabo is to eliminate these drawbacks of conventional technology,
The purpose is to provide a highly reliable printer that can be operated at high speed.

[Embodiments of the invention]

Next, embodiments of the present invention will be described with reference to the drawings. 1st
The figure is a schematic configuration diagram of the printer viewed from above.

There are four electromagnetic solenoids 2a on the frame l.

2bl 2c+ 2d+ are arranged side by side, and on the armatures 3a', 3b, 3c, and 3d, there are four moving plates 4a,
4b, 4c, and 4d are arranged in the vertical direction, and each moving plate 4a to 4d is individually movable in its longitudinal direction.

Selection plate groups 58 to 5-n are rotatably installed near the movable plates 48 to 4d, and the number of selection plates to be installed matches the maximum number of digits of the printer. Driving wheels 68 to 6n and type shafts 78 to 7n are arranged near each selection plate group 58 to 5n, and type wheels 7
8 to 7n face the platen roller 10 via the ink ribbon 8 and printing paper 9. The drive wheels 68~
6n and the number of type shafts 78 to 7n installed also match the maximum number of digits of the printer.

As will be explained in detail later, the electromagnetic solenoid 2° moving plate 42 selection plate group 5. The driving wheel 6 and the type wheel 7 work together to select the type from the type wheels 78 to 7n sequentially from the lower digit side.
After that, the platen roller 10 is pressed against the type wheels 78 to 7n via the ink ribbon 8 and printing paper 9.
It is designed to print lines all at once.

Next, the type selection mechanism will be explained. FIG. 2 is a partially exploded perspective view of the type selection mechanism. As shown in the figure, the selection board group 5 is made up of a trigger board 11, a first selection board 12, a second selection board 13, a third selection board 14, and a fourth selection board 15. It is configured. The trigger plate 11 is molded from synthetic resin, and includes first to fourth selection plates 12 to 1.
5 is made of an elastic metal plate.

As shown in FIG. 3, the trigger plate 11 has a through hole 16 in the center.
A boss portion 17 is provided which protrudes from one side (the back side in the figure). A trigger protrusion 18, an arcuate groove 19, an arcuate selection plate return groove 20, and a stopper one-step portion 21 are provided at predetermined positions around the boss portion 17, respectively.

As shown in FIG. 2 and FIGS. 4 to 7, the first to fourth selection plates 12 to 15 have slightly fan-shaped external shapes, and engagement holes 22a to 22d are formed in the center of each of the first to fourth selection plates 12 to 15, respectively. These holes are rotatably fitted onto the boss portion 17 of the trigger plate 11.

Elastic arms 23a to 23d are projected from each of the selection plates 12 to 15 along the rotating direction of the selection plates 12 to 15, and the tip of the elastic arm 23 is folded back as shown in FIG.
9 is formed. Elastic arm 23a of first selection plate 12
is located radially outermost than the other selection plates 13 to 15, and the second selection plate 13. Third selection board 14, fourth selection board 1
5, the position of the elastic arm 23 becomes closer to the inside in the radial direction.

The first selection plate to the fourth selection plate 12 to 15 have engaging holes 22a to
Cut-out pieces 24a to 24d protruding in the same direction are formed at positions approximately the same distance away from 22d. In addition, the first selection plate 123 selection plates 12 to 14 have cut and raised pieces, and suitable tolerance grooves 2 on approximately the same circumference as the 24a to 24c.
5a to 25c are formed.

1 The fourth selection plate 15 is provided with a spring hook part 26 by cutting and raising at a position radially outward from the cut and raised piece 24d thereof, and an arcuate toothed part 2 is further provided at a position radially outward from the spring hook part 26.
7 is formed. One end of a tension spring 28 is engaged with the spring hook 26, so that the fourth selection plate 15 is always elastically biased in the direction of arrow A in FIG.

First selection plate 124 selection Fi12 for trigger plate 11
15 are stacked one on top of the other in order and supported by the boss portion 17, and the cut and raised piece 24a of the first selection plate 12 is movably inserted into the arcuate groove 19 of the trigger plate 11. Voice number 2
The cut-and-raised piece 24b of the selection plate 13 is connected to the allowable groove 2 of the first selection plate 12.
5a, the cut and raised piece 24c of the third selection plate 14 is attached to the second selection plate 1.
The cut and raised pieces 24d of the fourth selection plate 15 are movably inserted into the allowance grooves 25b of No. 3 and the allowance grooves 25c of the third selection plate 14, respectively.

The arcuate groove 19 has a length that allows the first selection plate 12 to be rotated by the type wheel 7 by an amount corresponding to eight characters. The length of the allowable length 1125a of the first selection plate 12 is such that the second selection plate 13 can be rotated by the amount of rotation corresponding to four characters on the type shaft 7. 2nd selection board 1
The length of the allowable groove 25b of No. 3 is determined by the length of the third selection plate 14
The length is such that it allows rotation by the amount of rotation equivalent to two characters. Further, the length of the allowable groove 25c of the third selection plate 14 is such that the fourth selection plate 15 is allowed to be rotated by the amount of rotation corresponding to one character by the type wheel 7.

Further, the claw portion 29a of the elastic arm 23a on the first selection plate 12 engages with the claw locking edge 30a of the trigger plate 11, and the claw portion 29b of the elastic arm 23b on the second selection plate 13 engages with the claw locking edge 30a of the trigger plate 11. The claw portion 29c of the elastic arm 23c of the third selection plate 14 engages with the claw locking edge 30b of the second selection plate 13, and the fourth selection plate 1
The claw portion 29d of the elastic arm 23d at 5 engages with the claw locking edge 30d of the third selection plate 14. These trigger plates 11 and the first to fourth selection plates 12
Each selection plate group 58-5n consisting of ~15 polymers has a first
As shown in the figure, it is rotatably supported on a selection shaft 31.

FIG. 9 is a diagram for explaining the type selection mechanism.
As shown in the figure, a type shaft 32 is installed above and parallel to the selection shaft 31. The arcuate teeth 2 of the fourth selection plate 15 are rotatably supported on the type wheels 78 to 7n.
A gear 33 meshing with the type shaft 7 is integrally formed on each side surface, and a desired type portion 34 is provided on the outer periphery of the type shaft 7.

The platen roller IO is supported by a roller shaft 36 together with a side plate 35, and is pressed against the type portion 34 only during printing.

Further, as shown in the figure, a drive shaft shaft 37 is disposed diagonally below the selection shaft 31 in parallel, and each of the drive shafts 68 to 6n is attached so as to rotate together.

A trigger protrusion 1 of a trigger plate 11 is provided on the outer periphery of the drive wheel 6.
One drive pawl 38 is provided for engaging with 8.

Four amateurs 38 as shown in Figures 2 and 9
3d is rotatably supported by a support shaft 40 hanging from the support plate 39. A connecting recess 40 is provided in each of the four movable plates 4a to 4d arranged vertically in front of the armatures 38 to 3d, so that the first armature 3a is connected to the first movable plate 4a and the second armature 3b.
is connected to the second moving plate 4b, the third armature 3c is connected to the third moving plate 4C, and the fourth armature 3d is connected to the fourth moving plate 4d.

A selection board group 58 is provided on the side of each movable board 4 facing the selection board group 5.
The same number of teeth 41 as ~5n, that is, the same number of digits, are provided. As shown in FIG.
The claw portion 29b of the selection plate 13 contacts the tooth portion 41 of the second moving plate 4b, the claw portion 29c of the third selection plate 14 contacts the tooth portion 41 of the third moving plate 4c, and the claw 29d of the first selection plate 12 contacts the tooth portion 41 of the second moving plate 4b. The tooth portions 41 of the four moving plates 4d are opposed to each other.

As described above, the fourth selection plate 15 is pulled in the direction of arrow A as shown in FIG. 2 by the tension spring 28. The claw portion 29d of the fourth selection plate 15 is the third selection 'Fil 4 L:
Oh, tl[@+h#30 a h. @@I,C,7$4
The biasing force of the selection plate 15 is transmitted to the third selection plate 14.

Further, the claw portion 29c of the third selection plate 14 comes into contact with the claw lock 1m30c on the second selection plate 13, and the third selection 'Jgi
Further, the claw portion 29b of the second selection plate 13 is brought into contact with the opening edge of the claw locking edge 30b of the first selection plate 12.

The biasing force of the 2nd!1 selection plate 13 is transmitted to the first selection plate 12. Furthermore, the claw portion 29a of the first selection plate 12 comes into contact with the claw lock I#3oa on the trigger plate 11, and the biasing force of the first selection plate 12 is transmitted to the trigger ff1ll. And due to this bias in the direction of arrow A.

The first step part 2 of the stopper of the trigger plate 11 is in the state before type selection.
1 comes into contact with the upper surface of the support plate 39, and the waiting positions of the trigger Fill and the first selection plates 124 and selection plates 12 to I5 are secured. In this way, each selection plate group 58 to 5n is arranged in an orderly manner at the standby position by the support Fi 39, and in this state, the trigger protrusion 18 of each trigger plate 11 rotates along the rotational trajectory of the drive pawl 38 at each drive wheel 68 to 6n. It's within.

When selecting type, the drive shaft 6 is rotated in the direction of the arrow as shown in FIG. 2 by the driving force of a motor (not shown), and its drive pawl 38 engages with the trigger protrusion 18 of the trigger plate IJ. The trigger plate 11 is rotated in the direction opposite to the direction of arrow A.

The drive wheels 6 are mounted at equal intervals along the axial direction of the drive shaft shaft 37 by the maximum number of digits so as to form a pair with the selection plate group 5,
Further, as shown in FIG. 10, the drive pawls 38 formed on each drive wheel 6 are provided at positions shifted by a predetermined interval along the circumferential direction, and correspond to the lowest digit during one rotation of the drive shaft 37. The drive shaft 6 contacts the trigger plates 11a to lln at predetermined timings in order from the drive shaft 6 toward the upper digits. Further, as shown in FIG. 2, a digit position detection sensor 42 made of, for example, a reflective photosensor is attached coaxially with the drive shaft 37.

And the drive shaft 6 and trigger plate 11 corresponding to the digit position
A pulse signal is output from the 1-digit position detection sensor 42 shortly before the 1-digit position is engaged, and based on that signal, the electromagnetic solenoids 28 to 2d are activated in response to the character to be printed at the digit position.
Any or all of them are energized, and the energized state is maintained for a predetermined short time.

A little after the electromagnetic solenoid 2 is energized, the drive pawl 38 of the drive shaft 6 corresponding to the digit position engages with the trigger protrusion 18 of the trigger plate 11, and the rotational force of the drive shaft shaft 37 causes the tension spring 28 to become elastic. The trigger plate 11 is rotated in the opposite direction of the arrow A.

With this rotation, the first selection plate 124 and the selection plates 12 to 15 also rotate in the same direction, so that the first selection plate 12
The claw portion 29a of the movable Fi 4a engages with the tooth portion 41 of the second
The claw portion 29b of the selection plate 13 engages with the tooth portion 41 of the movable plate 4b, and the claw portion 29c of the third selection plate 14 engages with the tooth portion 4 of the movable plate 4c.
Furthermore, the claw portion 29d of the fourth selection plate 15 engages with the tooth portion 41 of the moving Fi4d.

Next, a specific example of type selection will be explained. When rotating the type shaft 7 at the reference position before print selection by the amount equivalent to one character, immediately after the pulse signal (type selection start signal) is output from the digit position detection sensor 42, the fourth electromagnetic solenoid 2d is rotated. energized and thereby amateur 3d
is magnetically attracted and locks the moving +Pi4d in place.

Note that the other first to third electromagnetic solenoids 2a
~2c is not energized, therefore moving plates 48~4c
is movable in its longitudinal direction.

In this state, the drive pawl 38 of the drive wheel 6 corresponding to the digit position
engages with the trigger protrusion 18 of the trigger plate 11 1, rotates the entire selection plate group 5 corresponding to the digit position in the opposite direction of arrow A, and moves the claws 29a to 29d of each selection plate 12 to 15. It is brought into contact with the teeth 41 of the plates 48 to 4d.

As mentioned above, the movable plate 4d is fixed so as not to move, and FIGS. 11(A) to (C) show the situation when the claw portion 29d of the fourth selection plate 15 comes into contact with the tooth portion 41 of the movable plate 4d. Shown below.

The figure (A) shows the state before the claw portion 29d comes into contact with the tooth portion 41, and as the first selection plate group 5 rotates, the claw portion 29d remains engaged with the claw locking edge 30d of the third selection plate 14. The claw portion 29d approaches the inclined side 41a of the tooth portion 41. The figure (B) shows the claw part 2.
9d shows an initial state in which the tooth portion 41 is in contact with the inclined side 41a, and as the selection plate group 5 rotates, the claw portion 29d
approaches the tooth portion 41 side as shown by the arrow, and the claw portion 29d comes into sliding contact along the inclined side 41a, thereby causing the elastic arm 2
3d begins to bend outward. Figure (C) shows the state in which the claw portion 29d is closest to the tooth portion 41, and as the first selection plate group 5 rotates, the claw portion 29d reaches the root of the inclined side 41a. As a result, the elastic arm 23d is deflected the most, and the engagement with the claw locking edge 30d of the adjacent third selection plate 14 is released.

FIGS. 12(A) and 12(C) are diagrams showing the situation when the claw portion 29a of the first selection plate 12 comes into contact with the tooth portion 41 of the movable plate 4a. The same figure (A) shows the state before the claw part 29a comes into contact with the tooth part 41, and as the selection plate group 5 rotates, the claw part remains engaged with the claw locking edge 30a of the trigger plate 11. 29a approaches the inclined side 41a of the tooth portion 41. Same figure (
B) shows an initial state in which the claw portion 29a is in contact with the inclined side 41a of the tooth portion 41, and as the selection plate group 5 rotates, the claw portion 29a approaches the tooth portion 41 side as shown by the arrow. Since the movable plate 4a is in a movable state, the movable plate 4a moves toward the paper as shown by the arrow as the claw portion 29a approaches. It will move to the left. The same figure (C) shows the tooth part 4.
1, and even if the claw 29a reaches the base of the inclined side 41a, the movable plate 4a escapes, so the claw 29a engages with the claw locking edge 30a. It remains as it is.

Similarly to the claw portion 29a of the first selection plate 12, the claw portion 29b of the second selection plate 13 and the claw portion 29c of the third selection plate 14 also engage the claw locking edge 30 even when the selection plate group 5 rotates. The engagement of the movable plate 4 is not released, but the movable plate 4 is simply pushed to the left.

Therefore, the trigger plate 11, the first selection plate 12, and the second selection plate 1
3 and the third selection plate 14 are connected by the engagement of the claw parts 29a to 29c and the claw locking edges 30a to 30c, respectively, so that after the engagement between the drive wheel 6 and the trigger plate 11 is broken, the trigger The plate 11 and the first selection plate 123 and the selection plates 12 to 14 are returned to the standby position by the tension spring 28. On the other hand, since the fourth selection plate 15 is disengaged from the third selection plate 14, the tension spring 28 causes the first selection plate 1 to move against the trigger plate 11.
It is returned in the direction of arrow A by the length of the second tolerance groove 25c, thereby rotating the type shaft 7 by an amount corresponding to one character with respect to the initial stage.

When rotating the type shaft 7 by an amount corresponding to one character, the third
Only the third electromagnetic solenoid 2c is energized to fix only the movable plate 4c, the engagement between the second selection plate 13 and the first selection plate 12 is released, and the third selection plate 14 and the fourth selection plate 15 are are returned together with the trigger plate 11 by the length of the allowable groove 25b of the second selection plate 13, thereby rotating the type wheel 7 by an amount corresponding to one character.

When rotating the type shaft 7 by seven characters, the electromagnetic solenoids 2b, 2c, and 2d are energized to rotate the movable plates 4b, 4c,
Fix 4d. As a result, the second selection plate 13 is disengaged from the first selection plate 12 and returned by the length of the allowable groove 25a. Further, the third selection plate 14 is disengaged from the second selection plate 13 and returned by the length of the allowable groove 25b. Further, the fourth selection plate 15 is disengaged from the third selection plate 14 and returned by the length of the allowable groove 25c.

As a result, the final fourth selection plate 15 rotates by the total allowable length of $ 25 a , 25 b , and 25 c with respect to the trigger plate 11 , thereby rotating the type shaft 7 by an amount equivalent to seven characters. . The position of the fourth selection plate 15 at this time is shown in FIG. 9 by a two-dot chain line.

FIG. 13 is an explanatory diagram showing the relationship between the amount of movement of the type part 34 on the type shaft 7 and the energization and de-energization of each electromagnetic solenoid S Q L 2 a to 2d. In the electromagnetic solenoids 5QL2a to 5QL2d in the figure, those shown with diagonal lines are energized, and the blanks are non-energized.

As is clear from this figure, 16 types of type can be selected by combining the energization and de-energization of the four electromagnetic solenoids, and only when the type wheel 7 is moved by an amount equivalent to 15 characters.
By exciting the two electromagnetic solenoids 28 to 2d,
For other type selections, fewer electromagnetic solenoids are required to be energized.

As soon as the type selection for one digit position is completed in this way, the power to the electromagnetic solenoid 2 is cut off, and with the subsequent rotation of the drive shaft 37, a type selection start signal for the next digit is sent from the digit position detection sensor 42. Similarly to the above, a predetermined electromagnetic solenoid 2 is energized based on the type selection signal, and type selection is performed by the cooperation of the trigger plate 6 corresponding to the first-order upper digit and the selection plate group 5. In addition, each type shaft 7a to 7
n can be freely rotated individually on the type spindle 32, so the type spindle 7 where the type selection is made sequentially from the lowest digit to the higher digit is in the approaching position regardless of the type selection of the adjacent type wheel 7. Retained.

After the desired character selection is made for each column, the printing of that line is done all at once. That is, after the selected type portion 34 is placed on the side facing the ink ribbon 8, the roller holder 43, which rotatably holds the platen roller 10, is rotated clockwise as shown in FIG. According to
Printing is performed by pressing the printing paper 9 and the ink ribbon 8 against the type portion 34 using the elasticity of the platen roller 10.

After the - digits have been printed all at once in this manner, the paper is fed by a paper feed mechanism (not shown) and the selection plates 12 to 15 are returned. This operation will be explained with reference to FIG. 14.

When one frame's worth of characters has been printed, the selection board 12 is displayed for each digit.
-15 are located at different positions, and in some cases the claw portion 29 remains disengaged from the claw lock I#30 on the adjacent selection plate. Therefore, by rotating the return member 44 shown in the figure, the selection plates 12 to 15 of all selection plate groups 58 to 5n are returned to the engaged state. This return member 44 is engaged with and supported by the selection shaft 31, and a return bar 46 having a length of one bone is attached to the tip of an arm 45 of the return member 44. When the return member 44 is in a standby state, it stops when its return bar 46 abuts against the support plate 39, as shown by the solid line in FIG. During the return operation, by rotating the selection shaft 31 clockwise, the return member 44 also rotates, and the tension spring 2
The selection plate, which had been rotated in the direction of arrow A (see FIG. 2), is pushed back clockwise by the elastic bias 8. Return bar 4
6 stops rotating when it comes into contact with the bottom of the selection plate return groove 20 of the trigger plate 11, as shown by the broken line in FIG.
In this position, the 111 portions 29 of all selection plates are engaged with the adjacent pawl locking edges 30, ready for character selection in the next row.

FIG. 15 is a timing chart of this printer from character selection to paper feeding operation.

As shown in the figure, the drive shaft shaft 37 rotates once at a constant speed based on a character selection signal from a control section (not shown), and during this period, a digit position detection sensor 42 sends a digit position detection sensor 42 at a predetermined timing.
pulse signals are sequentially output.

Based on the first pulse signal, the electromagnetic solenoid 2 is energized according to the type of character to be printed on the lowest digit,
When engaged with the drive shaft 6 corresponding to the lowest digit, the corresponding selection plate group 5 rotates, and the type @7 is selected via the fourth selection plate 15 based on whether each movable plate 4 is fixed or not. Rotate by the desired amount. In addition.

When the rotation of the selection plate group 5 corresponding to the lowest digit is completed, the next second pulse signal is output.

After all, when the type shaft 7 is being rotated using the force of the tension spring 28, the type selection operation for the next upper digit is started. The most significant digit (in this example, 1) is
When the selection of characters up to 8 digits is performed, the platen roller 1O rotates to print the characters all at once, and then the return member 44 returns the selection plates 12 to 15 and at the same time feeds the paper. Ru.

In the case of the above embodiment, the iron piece of the armature 3 is placed near the electromagnetic solenoid 2, and by energizing the electromagnetic solenoid 2, the iron piece of the armature 3 is attracted and fixed by magnetic attraction (by rotating the armature 3). ing. However, with this one, it takes time to rotate the amateur 3,
This slows down the selection of type. As shown in this point part 16, a two-wound helical spring 47 with weak spring elasticity is attached,
By doing so, the amateur '73 is placed in the suction position (fixed position W1).
2) The armature 3 is fixed at the same time as the 6-configuration 1° slide jf/electromagnetic ``id'' is energized, which always maintains 1°, and the time can be shortened. The elasticity of the helical spring 47 is such that when the electromagnetic solenoid 2 is not energized, the movable plate 4 can be easily moved when the claw portion 29 of the selection plate comes into contact with the tooth portion 41 of the movable plate 4. It needs to be lightweight.

FIG. 17 is an enlarged side view of essential parts showing a modification of the moving plates 48 to 4d. In this example, the width of the movable plate 4 is gradually increased from the first movable plate 4a to the fourth movable plate 4d, and the position of the tooth portion 41 is actively sequentially adjusted as shown in FIG. It's shifted.

In this way, all the movable plates 48 to 4d are fixed, and when the selection plate group 5 is rotated by the drive wheel 6, they are engaged sequentially from the innermost claw part 29d to the outer claw part 29a. will come off. This thing comes down to it.

The configuration is such that the engagement is surely released from the side biased by the elastic biasing means such as the tension spring 28, and the amount of rotation of the fourth selection plate 15 meshing with the type shaft 7 is gradually increased. It has become.

As shown in FIG. 9, in a structure in which the width dimensions of the movable plates 48 to 4d are the same and the claw portions 29a to 29d of each selection plate 12 to 15 are arranged in a straight line, due to variations in component dimensions or mounting positions, etc. Claw portion 29a on each selection plate 12 to 15.
~29d tend to come off at different timings, and as a result, the rotation of the fourth selection vi15 may not be smooth. In this respect, by adopting the configuration as described above.

The rotation of the fourth selection plate 15 is reliably smooth.

Although the width dimensions of the movable plates 4a to 4d are different in the above modification, the present invention is not limited to this.
For example, the teeth 4 of the moving plates 4a to 4d! In short, any structure may be used as long as the timing at which the claw portion 29 comes off is first removed from the elastic biasing side by changing the dimensions of the elastic arms 23a to 23d of the selection plates 12 to 15, or by changing the lengths of the elastic arms 23a to 23d of the selection plates 12 to 15.

FIG. 18 is an enlarged side view of a main part showing a modification of the elastic biasing means in the fourth selection plate 15.

In this example, the selection plate 15 is provided with an elastic contact member 48 made of, for example, a plate spring or a wire spring, which is elastic on the surface of the selection shaft 31 . Then, when it is necessary to apply at least an elastic biasing force to the selection plate 15, the selection shaft 31 is rotated in the direction of the arrow, and the selection plate 15 is moved in a predetermined direction by the frictional force generated between the selection shaft 31 and the elastic contact member 48. It can also be elastically biased.

In addition to this example, it is also possible to interpose a spring clutch between the one selection plate 15 and the selection shaft 31, and to bias the selection plate 15 in one direction using the elastic force of the spring clutch.

[Summary of the invention]

As described above, the present invention includes a type shaft having a large number of type parts and teeth for rotation, and rotatably arranged in parallel in the row direction in the same number as the maximum number of digits, a toggly protrusion, and a circular arc. A trigger plate with a groove and a pawl locking part, and an elastic arm with a pawl at the tip.

A first selection plate provided with an arcuate groove, a protruding piece, and a pawl locking portion, and a second selection plate provided with an elastic arm having a pawl portion at the tip, an arcuate groove, and a tooth portion that meshes with the tooth portion of the type shaft. the trigger plate, the first selection plate, and the second selection plate are overlapped so that the trigger plate and the second selection plate are on the outside, and the projecting piece of the first selection plate is Insert it into the arc groove of the trigger plate 2, engage the claw part of the first selection plate with the claw locking part of the trigger plate, and insert the protrusion of the second selection plate into the arc groove of the first selection plate. and a group of selection plates arranged in parallel so as to be rotatable in the row direction by the same number as the maximum number of digits, with the pawl portion of the second selection plate being engaged with the pawl locking portion of the first selection plate; a rotational biasing means for rotationally biasing the second selection plate in a direction in which a claw portion of the second selection plate is disengaged from a claw locking portion of an adjacent selection plate; arranged in parallel with each of the selection plate groups in pairs; a driving means that engages with a trigger protrusion of a trigger plate to rotationally bias the selection plate group in a direction opposite to the biasing direction of the rotational biasing means;

'A first movable plate that is abutted by the claw portion of at least the first selection plate and a second movable plate that is abutted by the claw portion of the second selection plate, each of which is provided with a tooth portion facing the selection plate group. and.

A movable plate fixing/non-fixing means is provided for fixing or movable the movable plate.

The timing when the claw part engaged with the claw locking part comes into contact with the teeth of the fixed movable plate to release the engagement is faster on the second selection plate than on the first selection plate. It is characterized in that it is configured to be disengaged.

〔Effect of the invention〕

By adopting the above-mentioned configuration, the number of fixed and non-fixed means such as electromagnetic solenoids can be reduced.
In addition, the amount of rotation of the second selection plate (type shaft) becomes accurate,
There are no typographical selection errors.

As a result, the reliability of the printer can be improved, and the printer can be made faster, lighter, and lower in cost.

[Brief explanation of the drawing]

The drawings are all for explaining the printer according to the embodiment of the present invention. Fig. 1 is a schematic diagram of the printer viewed from above, Fig. 2 is a partially exploded perspective view of the type selection mechanism, and Fig. 3 is the trigger. A side view of the board, Figure 4 is a side view of the first selection board, and Figure 5 is a side view of the board.
The figure is a side view of the second selection plate, Figure 6 is a side view of the third selection plate, Figure 7 is a side view of the fourth selection plate, Figure 8 is a partially enlarged view of the elastic arm, and Figure 9 is a side view of the third selection plate. An enlarged side view of the main part to explain the type selection mechanism, Figure 10 is a side view showing the mounting state of the drive wheel, and Figures 11 (A), (B), (C1,) are the claws on the fixed moving plate. Fig. 12 (A), (B), and (C) are explanatory drawings showing the contact state of the claw part with the movable movable plate, and Fig. 13 shows the type characters on the type shaft. Fig. 14 is an enlarged side view of the main part to explain the return operation of the selection board, and Fig. 15 is an explanatory diagram showing the relationship between the amount of movement of each electromagnetic solenoid and energization/de-excitation of each electromagnetic solenoid. Timing chart up to paper feed operation, 1st
Figure 6 is a plan view of the main part showing another example of the electromagnetic threadroid, the first
Figure 7 is an enlarged side view of main parts showing a modification of the moving plate, No. 18I.
vl is an enlarged side view of a main part showing a modification of the elastic biasing means in the selection plate. 2.2a-2d... Electromagnetic solenoid, 3,3a
~3d...Amateur, 4,4a~4d...
. . . Moving plate, 6, 6a to 6n . . . Drive shaft, 7.
7a-7n...Type shaft, 11...Trigger plate, 12...First selection board, 13...Second
Selection board, 14...Third selection board, 15...
Fourth selection plate, 18...Trigger protrusion, 19...
Arc-shaped groove, 23.23a~23d...Elastic arm, 24,24a 24cl--cut and raised piece, 25° 25a~
25c... Permissible groove, 27... Arc-shaped tooth portion. 28...Tension spring, 29.29a-29 rl・
...Claw portion, 30, 30a to 30d...Claw locking edge,
33...Gear, 34...Type section, 38
... Drive claw, 41 ... Teeth, 47 ... Helical spring, 48 ... Elastic contact member. Agent Patent Attorney Takeshi Kenjibu Horse 11 Figure (A) (B) (C) Kabuto 12f ¥] (A) (B) (C) Figure 13 Oni +4m ■

Claims (1)

[Scope of Claims] A type shaft having a large number of type parts and teeth for rotation, the number of which is the same as the maximum number of digits, and which are rotatably arranged in parallel in the row direction, a trigger protrusion, an arcuate groove, and A trigger plate provided with a pawl locking portion, an elastic arm having a pawl portion at its tip, a first selection plate provided with an arcuate groove, a protrusion and a pawl locking portion, an elastic arm having a pawl portion at its tip, and a circular arc. at least a second selection plate provided with a groove and a tooth portion that meshes with the tooth portion of the type shaft;
Overlap the trigger plate, first selection plate, and second selection plate so that the trigger plate and the second selection plate are on the outside, and insert the protrusion of the first selection plate into the arcuate groove of the trigger plate. insert the first selection plate, engage the claw part of the first selection plate with the claw locking part of the trigger plate, insert the protrusion of the second selection plate into the arcuate groove of the first selection plate, and then press the second selection plate. A group of selection plates arranged in parallel so as to be rotatable in the row direction by the same number as the maximum number of digits, the claws of which are engaged with the claw locking parts of the first selection plates. rotational biasing means for rotationally biasing the second selection plate in a direction in which a claw portion of the second selection plate is disengaged from a claw locking portion of an adjacent selection plate; a driving means that is provided and engages with a trigger protrusion of a trigger plate to rotationally bias the selection plate group in a direction opposite to the biasing direction of the rotational biasing means; Teeth portions facing the selected Fi groups were respectively provided. At least a first movable plate that the claw portion of the first selection plate abuts, a second movable plate that the claw portion of the second selection plate abuts, and the movable plate is fixed or movable. Fixed moving plate,
a non-fixing means, the timing when the claw part engaged with the claw locking part contacts the tooth part of the fixed movable plate to release the engagement is set to a timing that is earlier than the first selection plate. A printer characterized in that the second selection plate is configured to be disengaged earlier.