JPS62189181A - Printer - Google Patents

Abstract

PURPOSE:To provide a printer reduced in power consumption and capable of being assembled with favorable operability, by a construction wherein a type wheel for which type selection is not required is fastened at a predetermined position by engaging a selection pawl being in a stand-by state with a fastening projected part of a selection ratchet. CONSTITUTION:When a tooth part 13 of a selection ratchet 6 is fastened to a selection pawl 25 to hold the rotation of the ratchet 6, the subsequent rotation of a driving shaft 2 in the direction of an arrow D is accompanied by fastening of a substantially central part of a first arm part 22 of a driving pawl 20 to a release pin 17 provided on the ratchet 6 and an outward movement of the part 22. By this, a projection 21 of the first arm part 22 is disengaged from a notched part 3 of the driving shaft 2, and the transmission of the rotating force of the driving shaft 2 to the ratchet 6 and a type wheel 5 is cut off. A pawl part 26 of the selection pawl 25 is engaged into a ink groove 8 provided in the type wheel 5, for obviating a positional deviation of the type wheel 5 for which type selection has been performed.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a printer, and particularly to a printer that rotates a type wheel in a row in which no type is selected during type selection and a type wheel during paper feeding during these periods. This invention relates to a printer with an improved mechanism for separating it from a drive shaft.

(Prior Art) A plurality of type wheels having type bodies on the circumferential side are mounted on a rotary shaft arranged parallel to a platen around which recording paper is wound.
A printer has been proposed in which the printers are arranged in eight rows, etc., and the rotation of each type wheel is individually controlled to perform desired printing.

Conventionally, as an example of this type of printer,
As described in Japanese Patent Publication No. 47872 and Japanese Patent Publication No. 55-31749, a selection ratchet is formed in the body of each type wheel, and a selection pawl that can be engaged with each of these selection ratchets, and these A printer has been proposed that includes a drive source, such as a solenoid, for driving the selection pawl so that the selection pawl engages with the selection radiet or disengages the selection pawl from the selection ratchet.

That is, in the printers of these earlier applications, by engaging the selection pawl with the M#R ratchet using each solenoid, the transmission of the rotational force of the rotating shaft to the type wheel is cut off, and the desired type can be selected. I can just do it (,
For a type wheel that does not require type selection when selecting type, or a type wheel that only feeds paper without printing, transmission of rotation can be cut off by the engagement of the selection ratchet and selection pawl. Therefore, by transmitting power between the rotary shaft and the type wheel again using the reset mechanism after such transmission is canceled, the type wheels in all columns can be returned to the standard starting position.

(Problem to be Solved by the Invention) However, in the above blinking light (■), the rotational force is transmitted from the rotating shaft to the type wheel between the notch formed in the rotating shaft and the drive claw held on the type wheel. Because it depends on the frictional force of
Alternatively, there is a concern that the drive pawl may come off the rotating shaft due to the large inertia force upon startup. In addition, in order to eliminate such concerns, the spring horns of the drive claws must be set large, but if the spring force of the drive claws is increased, the spring force of the drive claws related to the type wheels in multiple rows, for example, all 18 rows, can be increased. As the type wheel becomes larger, the torque that drives the rotating shaft increases when the type wheel is stopped, which increases the manufacturing cost due to the larger motor that drives the rotating shaft of the device, and the running cost due to increased power consumption. This will lead to a rise in prices.

In addition, the type wheel that has not been selected can be locked,
Even when locking the type wheel when only paper feeding is performed, the solenoid must be energized to drive the selection pawl in the same way as when selecting type, so there is a problem that power consumption increases from a different perspective than the above. was there.

Therefore, an object of the present invention is to provide a printer that is inexpensive and has good assembly workability.

(Means for Solving the Problems) In order to achieve the above object, the present invention includes a drive shaft having a notch on the circumferential side, a type body rotatably attached to the drive shaft, and a typeface on the circumferential side. a drive pawl held by the type wheel and having a protrusion that can be engaged with the notch of the drive shaft; a drive pawl rotatably attached to the type wheel via the drive pawl; A selection ratchet that has an engaging part that can be engaged with the user, and has a plurality of teeth and one locking protrusion on the circumferential side, and a selection ratchet that engages with these teeth and the locking protrusion to rotate the selection ratchet. With a lockable selection claw,
and a driving means for driving the selection pawl, and when selecting a type, the selection pawl in a standby state is driven in a direction to engage with the teeth and locks the selection ratchet, thereby driving the selection ratchet. When the engaging portion of the driving pawl engages with the driving pawl, and the engagement between the protrusion of the driving pawl and the notch of the driving shaft is released, and no character selection is performed, the selection pawl in the standby state It is characterized in that the selection ratchet is locked and the engagement between the protrusion of the drive pawl and the notch of the drive shaft is released when the locking convex portion engages with the locking protrusion.

(Function) That is, when the selection ratchet is locked by driving the selection pawl, the drive pawl, which rotates integrally with the drive shaft and the type wheel, engages with the engaging portion of the selection ratchet that is in the locked state. As a result, the engagement between the protrusion of the drive pawl and the notch of the drive shaft is released, and the desired type is selected. In addition, for type wheels that do not require type selection or for type wheels that only feed paper, the selection pawl in the standby state and the locking protrusion of the selection ratchet automatically engage. As a result, the protrusion of the drive pawl and the notch of the drive shaft are disengaged from each other and locked in a predetermined position in the same manner as described above.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a schematic side view of a printer according to an embodiment of the present invention. In the figure, reference numeral 1 denotes a rotating shaft, and the rotating shaft 1 is rotated forward or reverse by the driving force of a motor (not shown) via a gear train to be described later. Reference numeral 2 denotes a drive shaft which rotates coaxially with this rotating shaft 1, and two notches 3.4 are formed on the circumferential surface of the drive shaft at positions facing each other at 180 degrees in the axial direction.

5 is a type wheel attached to the drive shaft 2, and 6, indicated by a two-dot chain line, is a selection ratchet also attached to the drive shaft 2.

FIG. 2 is a plan view of the type wheel 5, and FIG. 3 is a front view of the selection ratchet 6. As shown in Figure 2,
On the outer peripheral surface of the type wheel 5, for example, ro, 1.2...
...Two groups of typefaces 7.7' are provided, with g, +, -, x, ÷-1, etc. as one group, and each typeface 7,7' is provided on the inner circumference side. There is a plurality of lock grooves 8 corresponding to the bearing 9, and a bearing 9 in which the drive shaft 2 is inserted in the center.
has been erected.

A gap lO is formed in a part of the bearing 9, and an engagement shaft 11 and a support shaft 12 are connected to the type wheel 5 on the outer periphery of the bearing 9.
They are planted so as to face each other about 180 degrees across the center of the two.

On the other hand, as shown in FIG.
3 and one locking protrusion 14, and a hole 15 into which the bearing 9 of the type wheel 5 is inserted is bored in the center. A pair of release pins 16 and 17 are erected on the outer periphery of the hole 15 at a predetermined interval, and are arranged in a manner corresponding to the engagement shaft 11 and the support shaft 12 of the type wheel 5 to sufficiently accommodate the release pins 16 and 17. Oval engagement hole 18°19 as much as possible
is drilled.

Returning to FIG. 1, reference numeral 20 denotes a drive pawl disposed between the type wheel 5 and the selection ratchet 6, and the driving pawl 20 transmits the rotational force of the rotary shaft 1 to the type wheel 5.

This drive claw 20 has rigidity and has a notch 3 of the drive shaft 2.
．． a first arm 22 having a protrusion 21 that can be engaged with 4;
It consists of a second arm portion 24 having elasticity and a sliding portion 23 that comes into elastic contact with the engagement shaft 11 of the type wheel 5;
The base of the first arm 22 is rotatably inserted into the support shaft 12 of the type wheel 5. On the other hand, as shown by the two-dot chain line in the figure, both release pins 16 and 17 of the selection ratchet l-6 are located near the first arm portion 22 via the protrusion 21 of the drive pawl 20, and the type wheel 5 The ends of the engaging shaft 11 and the supporting shaft 12 are respectively fitted into tooth engaging holes 18.1 of the selected threads 6.
It is located at 9 yen.

Further, 25 shown in FIG. 1 is a selection pawl that can lock the rotation of the selection ratchet 6, and the selection pawl 25 is connected to the teeth 13 of the selection ratchet 6, the locking protrusion 14, and the locking groove 8 of the type wheel 5. Each has an engageable pawl 26 at its tip, a hole 28 in the center into which a rotating shaft 27 is inserted, and a cam pawl 30 that engages with a reset cam 29 at its rear end. .

31 is a drive means capable of selectively transmitting the rotational force of the rotation shaft 27 to the selection pawl 25, for example, a VL magnetic clutch;
Reference numeral 2 denotes a locking spring capable of holding the selection pawl 25 in a state of engagement with the selection ratchet 6, and numeral 33 denotes a pressing spring that cooperates with this locking spring 32 to hold the selection pawl 25 in a state away from the selection ratchet 6. It is.

FIG. 4 shows the above-mentioned type wheel 52 selection ratchet 6,
FIG. 3 is an exploded perspective view showing the relationship between the drive pawl 201, the selection pawl 25, and the electromagnetic clutch 31. FIG. As shown in the figure, the electromagnetic clutch 31 includes an electromagnetic coil 34. Holding stand 35. It is roughly constituted by a yoke 361 and a rotating body 37. The electromagnetic coil 34 has a hole 38 in the center thereof into which the rotating shaft 27 is inserted, and is held by a fan-shaped projection 39 on the upper part of the holding table 35. A cylindrical yoke 36 is mounted so as to surround this electromagnetic coil 34, and has a 90 mm diameter on its negative side.
Four notches 40 are formed at one-degree intervals. A hole 41 into which the rotating shaft 27 is inserted is formed in the center of the rotating body 37 made of a non-magnetic material, so that the rotating shaft 27 and the rotating body 37 rotate together, and the peripheral wall of the rotating body 27 Four protrusions 42 that engage with the notches 40 of the yoke 36 are also formed at 90 degree intervals. The electromagnetic clutch 31 configured in this manner can rotate two selection pawls, that is, the first selection pawl 25 and the second selection pawl 25' in the figure. These first and second selection claws 25.2
5' has a claw part 26, 26' at the tip, a hole 28, 28' in the center, a cam 30, 30' at the rear end, and a protruding part 39 of the holding base 35 at the bottom, as described above. Slightly larger fan-shaped notches 43 and 43' are formed corresponding to the shape of the .

These first and second selection claws 25°25',
When assembling the electromagnetic clutch 31, the yoke 36 is attached to the electromagnetic coil 34 so as to surround the electromagnetic coil 34 as described above, and each protrusion 42 of the rotating body 37 is arranged so as to fit into each notch 40 of the yoke 36. be done. Further, both selection claws 25 and 25' are rotatable relative to the rotation shaft 27, and their notches 43 and 43' are connected to the holding base 3.
The rotary body 37 is attached to the protrusion 39 of the rotary shaft 27 so as to fit into the protrusion 39 of the rotary shaft 27 as described above. In this assembled state, both selection claws 25.2
5' and the body portions 44 and 44' are arranged to face both sides of the yoke 36.

On the other hand, the type wheel 51 selection ratchet 6 and drive pawl 20 described above are attached to the drive shaft 2 in the following manner.

That is, for example, the bearing 9 of the first type wheel 5 is inserted into the drive shaft 2, then the hole of the drive pawl 20 is inserted into the support shaft 12 of the first type wheel 5, and the protrusion 21 of the first arm portion 22 is inserted. is inserted into the cavity 10 of the bearing 9, and then, for example, the protrusion 21 is engaged with the notch 3 of the drive shaft 2. Further, the sliding portion 23 of the second arm portion 24 is connected to the first type wheel 5.
It is mounted so as to come into elastic contact with the engagement shaft 11 of.

The hole 15 of the first selection ratchet 6 is then inserted into the bearing 9 of the first type wheel 5 and its release pin 16,1
．． 7 on the inside of the first arm portion 22 and its engagement hole 18.
19 are attached to the first type wheel 5 so as to correspond to the engagement shaft 11 and the support shaft 12, respectively.

The drive shaft 2 is provided with a second type wheel 5', a selection ratchet 6' and a drive pawl 2 in the same way as the first type wheel 5, the first selection ratchet 6 and the drive pawl 20 described above.
0' is installed. That is, the bearing 9' of the second type wheel 5' is inserted into the drive shaft 2, and then the drive claw 20'
The hole is inserted into the support shaft 12' of the second type wheel 5', the protrusion 21' of the first arm 22' is inserted into the cavity 10' of the bearing 9', and then this protrusion 21' is driven. Axis 2
is engaged with the notch 3 of. Further, the sliding portion 23' of the second arm portion 24' is connected to the engagement shaft 11 of the second type wheel 5'.
′. The hole 15' of the second selection ratchet 6' is then inserted into the bearing 9 of the second type wheel 5', so that its release pin (not shown) is inside the first arm 22' and its It is attached to the second type wheel 5' so that the engagement holes 1B' and 19' correspond to the engagement shaft 11' and the support shaft 12', respectively.

and the above-mentioned first type wheel 5. First selection ratchet 6, second type wheel 5'.

The second selection ratchet 6' is connected to the first selection ratchet 6.
The phase of the tooth 13 of the second selection ratchet 6' and the tooth 1 of the second selection ratchet 6'
The teeth 13' are arranged on the drive shaft 2 so that the phases of the teeth 13' are different from each other, for example, shifted by 1/2 pitch from each other, that is, the teeth 13' are located at positions corresponding to the spaces between the teeth 13.

Although not shown, two type wheels 5. 5', selection ratchet 6, 6'.

A plurality of combinations, for example nine sets, of the drive pawl 20, 20', the selection pawl 25, 25', and one electromagnetic clutch 31 are arranged along the axial direction of each of the drive shaft 2 and the rotation shaft 27.

FIG. 5 is an explanatory diagram showing the engagement relationship between the drive shaft 2 and the drive pawls 20, 20', and FIG.
FIG. 4 is an explanatory diagram showing the engagement relationship between the selection claw 25 and the selection claw 25, 25'. Hereinafter, the character selection operation of the character wheel 5.5' will be explained mainly using these figures.

First, as shown in FIG. 5(a), the notch 3 of the drive shaft 2
The protrusion 21.21' of the drive pawl 20.20'' is in the engaged state, and as shown in FIG.
I was in a standby state where I couldn't get over the 2.32' mountain.
For example, when the drive shaft 2 and the rotation shaft 27 are rotated in the direction of the arrow A in FIGS. 5 and 6 by a motor (not shown), as the drive shaft 2 rotates, a notch appears as shown in FIG. 5(a). 3
The rotational force is transmitted to the driving pawl 20.20' by the engagement with the protrusion 21.21' of the driving pawl 20.20', and this rotational force is further transmitted from the first arm 22 of the driving pawl 20.20'. Release pins 16, 17.1 of selection ratchet 6.6'
6′.

17', which causes the type wheel 5°5'
The selection ratchets 1-6, 6' and the drive shaft 2 rotate together in the direction indicated by the arrow. During this time, although the rotating body 37 and the yoke 36 rotate with the rotation of the rotating shaft 27, the rotational force of the rotating shaft 27 is not transmitted to the selection claws 25 and 25', so that these selections cannot be performed. Claw 25.25'
is maintained in the standby state shown in FIG. 6(a).

and the desired type body 7 of the first type wheel 5, for example.
Or when 7' comes close to the printing position, the Q electromagnetic coil 34 is energized, which causes the selection claw 2 to
The body portion 44.44' of 5.25' is attracted to the side end surface of the cork 36. Therefore, the selection claw 25.25' is the sixth
As shown by arrow B in Figures (b) and (c), the yoke 36
At this time, the first selection claw 2
5, the claw portion 26 is connected to the tooth portion 13 of the first selection ratchet 6.
As shown in FIG. 6(b), the distal end of the selection pawl 25 climbs over the peak of the locking spring 32 and rotates in the direction of arrow B, causing the pawl portion 26 and the tooth portion 13 to is engaged, thereby locking rotation of the first selection ratchet l-6. This state is stably maintained by the spring force of the locking spring 32. In this way, the first selection claw 25
When the rotation of the first selection ratchet 6 is stopped, the tip of the first arm portion 22 of the drive pawl 20 is rotated as the drive shaft 2 continues to rotate in the direction of the arrow in FIG. 5(a). is engaged with a release pin 16 provided on the first selection ratchet 6 and moves outward, that is, this driving pawl 20 is expanded against the spring force of the second arm 24, thereby causing the fifth selection ratchet 6 to move outward. As shown in Figure (b), the engagement between the protrusion 21 of the first arm 22 and the notch 3 of the drive shaft 2 is released, and the rotational force of the drive shaft 2 is changed to the first selection ratchet 6 and the first selection ratchet 6. The transmission to the type wheel 5 is interrupted. Note that at this time, the first type wheel 5
The engagement shaft 11 and support shaft 12 provided in the first selection ratchet 6 are inserted into the engagement hole 18. as shown in FIG. 5(b).
19 and thereby the first type wheel 5
The relative position between the first selection ratchet 6 and the first selection ratchet 6 is regulated.

Further, when the second arm portion 24 of the drive claw 20 is expanded, the sliding portion 23 at the tip thereof is bent in the direction of expansion of the arm portion 24 of the cylinder 2, and the engagement shaft of the first type wheel 5 is bent. 1
1, it slides in sliding contact with the engagement shaft 11 with a relatively small frictional force, and since the engagement shaft 11 is provided at a position opposite to the support shaft 12 through the center of the drive shaft 2, the 2
The arm part 24 can be lengthened and its spring constant can be set small,
That is, the protrusion 21 of the drive claw 20 is connected to the notch 3 of the drive shaft 2.
, 4 can be made large, and the load when they are disengaged can be made small.

On the other hand, the second selection claw 25' is 1/2 as described above.
As the pitch shifts, the claw 26' moves to the tooth 13' of the second selection ratchet 6' as shown in FIG. 6(c).
and waits in this state. Therefore, the second selection ratchet 6' and the second type wheel 5' continue to rotate. Further, for example, when the electromagnetic coil 34 is de-energized in synchronization with the locking of the first type wheel 5, the transmission of the rotational force of the rotation shaft 27 to the second selection claw 25' is cut off. , the second selection pawl 25' returns to the standby state shown in FIG. 6(a) by the force of the locking spring 32. Therefore, regardless of the rotation of the drive shaft 2, the second selection pawl 25' and the second selection ratchet 6' do not engage with each other.

When the desired type body 7 or 7' of the second type wheel 5' reaches near the printing position, the electric V1"t coil 34
As a result, the second printing wheel 5', which is in a standby state, is positioned in the same manner as the first printing wheel 5 described above, that is, into the state shown in FIG. 6(b). Furthermore, the type bodies provided on the type wheel (not shown) are also positioned in the same manner as described above, thereby making it possible to perform the desired printing operation.

As mentioned above, the claw part 26°26' of the selection claw 25.25'
cam pawl 30.30' of the selection pawl 25.25' engages with the teeth 13. As shown in FIG. 6(b), is located at a position facing the stepped portion 45 provided on the reset cam 29. When the printing operation is completed, the rotation of the reset cam 29 causes the convex portion 46 provided on the reset cam 29 to come into contact with the cam pawl 30.30' of the selection pawl 25. All selected pawls, including pawls 25 and 25', are connected to locking springs 32.
Climb over the peak of arrow C in Figure 6 (b) and (c).
It rotates in the direction shown by and is held in the standby state again by the peak of the locking spring 32 and the pressing spring 33. When the selection pawl 25.25' is reversed in this way, the selection pawl 25.2
5' and the selection ratchet 6.6' are disengaged. In this state, the drive shaft 2 is moved, for example, as shown by arrow A in FIG. 5(a).
When rotated in the direction, the protrusion 2L21 of the drive claw 20.20'
' slips on the circumferential surface of the drive shaft 2, and when the notch 3 or 4 comes to a position facing the protrusion 21.21', the spring of the second arm 24.24' of the drive pawl 20.20' The force causes the protrusion 21.21' to engage the notch 3 or 4;
As shown in FIG. 5(a), the rotational force of the drive shaft 2 is again in a state in which it can be transmitted to the selection ratchet and the type wheel 5.degree. 5'. In addition, the selection pawl and drive pawl 9 selection ratchet relating to another set not shown.

Exactly the same operation is performed for type wheels and the like.

The series of operations described above is for the case where the drive shaft 2 is rotated in the direction of the arrow shown in FIG. Basically, the same operation is performed when rotating in the direction indicated by the arrow. That is, as shown in FIG. 5(c), for example, when the tooth portion 13 of the selection ratchet 6 is engaged with the selection pawl 25 and the rotation of the selection ratchet 6 is stopped, the subsequent rotation of the drive shaft 2 is stopped. With rotation in the direction indicated by the middle arrow in FIG. 5(c), the approximate center of the first arm portion 22 of the drive pawl 20 is engaged with the release pin 17 provided on the selection ratchet 6 and moves outward; As a result, the protrusion 2I of the first arm portion 22 and the cutout portion 3 of the drive shaft 2
The transmission of the rotational force of the drive shaft 2 to the selection ratchet 6 and the type body wheel 5 is cut off. However, in this case, since the direction of rotation of the drive shaft 2 is opposite to the rotational force that the type wheel 5 receives due to the rotation of the hammer, which will be described later, the rotation direction shown in FIG. As shown in c), the claw portion 26 of the selection claw 25 engages with the lock groove 8 provided on the type wheel 5. Regarding this point, see below (Printing operation).
This will be explained in detail in the section below.

Returning to FIG. 1 again, reference numeral 47 denotes a hammer disposed opposite to the row of type wheels 5, 48 denotes an error printing prevention plate disposed between these type wheels 5 and the hammers 47, and 49
50 is a paper guide that guides recording paper to a printing position (not shown); 50 is a paper feed roller disposed near this paper guide 49;
is a driven roller disposed opposite to the paper feed roller 50, and the upper recording paper is conveyed while being held between the paper feed roller 50 and the driven roller 51.

FIG. 7(a) is a plan view of the hammer 47, FIG. 7(b)
is a sectional view taken along the line E-E. As shown in these figures, the hammer 47 has a plurality of, for example, eighteen chevron-shaped pressing portions 52 corresponding to the number of the type wheels 5, and each pressing portion 52 is separated by a notch 53. The hammer 47 is made of, for example, a relatively hard synthetic resin material, but since a void 54 is formed inside the pressing portion 52, the hammer 47 maintains its surface hardness and is easily deformed.

Moreover, since the pressing parts 52 are separated from each other by the notches 53, even if the hammer 47, type wheel 5, etc. are slightly eccentric, a uniform pressing force can be applied to each type wheel. I can do it. Note that 55 indicated by a two-dot chain line in FIG. 1 is the locus of the tip of the hammer 47, that is, the tip of the pressing portion 52.

FIG. 8 is a plan view of the erroneous printing prevention plate 48.

As shown in the same figure and in FIG. 1, the erroneous printing prevention plate 48 is made of, for example, a bent metal sheet, and fixing ears 56 are formed on both sides of its lower end. In addition, a plurality of holes 57 are provided at predetermined intervals in the longitudinal direction.
are bored, and these holes 57 are connected to the type wheel 5.
For example, 18 are formed corresponding to the columns. The type bodies 7, 7' of each type wheel 5 correspond to the hammers 47 through these holes 57, and as is clear from FIG. The length of the protrusion 58 (l) shown in FIG. 8 is set to be approximately equal to one of the type bodies 7, 7' of the type wheel 5. Therefore, only the typeface selected for the printing position protrudes from the projection 58 of the hole 57 in the direction of the hammer 47, and the typeface located in the front-rear direction of the typeface selected for the printing position faces the hole 57. It does not protrude from the hole 57.

In addition, 59 in FIG. 1 is the first ink roll, and 60 is the second ink roll.
The first ink roll 59 is impregnated with, for example, red ink, and the second ink roll 60 is impregnated with, for example, black ink. These first and second ink rolls 59 and 60 are rotatably held by a roll holder 61, as shown in FIG. (only one of which is shown in the figure) is rotatably and slidably supported by, for example, a chassis (not shown). Further, the roll holder 61 is always urged toward the center of the drive shaft 2 by a spring member (not shown), and furthermore, a first cam pawl 63 and a second cam pawl are provided at one end of the roll holder 61. 64 are formed, and these first and second cam pawls 63 and 64 are formed slightly offset in the axial direction of the ink roll 59 and 60.

The ink rolls 59, 60 and roll holder 61 configured in this manner are driven by a switching cam 65 shown in FIG. Although this switching cam 65 is not shown in FIG. 1, it is designed to rotate in synchronization with the type wheel 5, and is, for example, provided integrally on the outside of the type wheel in the outermost row. . Further, as is clear from FIG. 10, a first cam groove 66 is provided on the outer periphery of one surface of the cutting cam 65, and a second cam groove 67 is provided on the outer periphery of the other surface, extending approximately half a circumference. and both cam grooves 66
．． 67 are arranged so that they do not overlap each other. and,
The first cam claw 63 of the roll holder 61 mentioned above faces the first cam groove 66 of the switching cam 65, and the roll holder 6
The second cam pawl 64 of the switching cam 65 faces the second cam groove 67 of the switching cam 65.

FIG. 11 is an explanatory diagram showing the engagement relationship between the roll holder 61 and the switching cam 65, and FIG. 12 is an explanatory diagram showing the engagement relationship between the roll holder 61 and the switching cam 65.
60 is an explanatory diagram showing the engagement relationship between the type wheel 60 and the type wheel 5. FIG. Below, we will mainly use these figures to create the ink roll 59.6.
0 inking will be explained.

First, as shown in FIG. 11(a), the roll holder 61
The first cam claw 63 of the switching cam 65 is connected to the first cam groove 6 of the switching cam 65.
6 (and the second cam claw 64 of the roll holder 61
12(a) when the cam claws 63 and 64 are both engaged with the outer peripheral surface of the switching cam 65. As shown, both ink rolls 59 and 60 are separated from the type body 7.7 of the type wheel 5. From this state, when the switching cam 65 rotates, for example, in the direction of arrow F in FIG. Although the second cam pawl 64 is still engaged with the peripheral surface other than the second cam groove 67, as shown in FIG. The ink roll 59 is pressed against the first type body 7 of the type wheel 5. This state continues until the first cam pawl 63 is in the first cam groove 66 and the second cam pawl 64 falls into the second cam groove 67, so that the first cam pawl 63 of the type wheel 5 Typeface 7
The ink of the first ink roll 59, for example, red ink, is applied to all the parts constituting the ink.

The switching cam 65 rotates until the first ink roll 59 finishes coating the final type body 7, that is, the
The switching cam 65 moves approximately 180 degrees from the state shown in Figure (a) as shown by the arrow F.
When the cylinder 1 rotates in the direction shown in FIG. 11(c), the first cam pawl 63, which had fallen into the first cam groove 66, rides on the circumferential surface of the cylinder 1 other than the cam groove 66. Instead, the second cam pawl 64 falls into the second cam groove 67, and as shown in FIG. 12(C), the first ink roll 5
9 separates from the first type 7 and enters the second ink roll 6
0 is pressed against the second type body 7'. This state is maintained for approximately half a rotation of the switching cam 65,
As a result, the ink of the second ink roll 60, for example, black ink, is applied to all parts of the second type body 7' of the type wheel 5. When the switching cam 65 rotates once from the state shown in FIG. the twelfth
As shown in Figure (a), both ink rolls 59, 60 are again separated from the type 7, 7'. This kind of behavior is
The same applies when the switching cam 65 rotates in the opposite direction to the above, and in either case, one of the ink rolls 59.6
0 is pressed against the type body 7.7', and in about half a turn in the latter half, the other ink roll 59.60 is pressed against the type body 7.7'.
is pressed against.

Next, the above-mentioned rotating shaft 1. Reset I Cam 29° Hammer 47. A transmission system for controlling the rotation of the switching cam 65 and the like will be explained using FIGS. 13 to 15.

Fig. 13 is a timing diagram showing the relationship between each operation during printing operation for one line), Fig. 14 is an explanatory diagram showing an outline of the transmission system, and Fig. 15 (a) and (b) are FIG. 3 is an explanatory diagram of a claw clutch/punch mechanism provided in the transmission system.

In FIG. 13, the drive shaft 2 is moved in either the forward or reverse direction during the printing operation for one line. The inking operation is performed during the first 1/2 rotation of the drive shaft 2, followed by the character selection operation (approximately 1/2 rotation), and printing is performed during the final 1/2 rotation. movement and paper feeding operation. Among these operations, the type selection operation is for positioning the type bodies 7, 7' of the type wheel 5 at the desired printing position, so the drive shaft in this case 2 needs to rotate slowly, and during the inking operation for pressing the ink roll 59, 60 against the type body 7.7' of the type wheel 5 and the paper feeding operation for conveying the recording paper, Since position control as described above is not required, the drive shaft 2 in this case needs to be rotated quickly.

Such control of the rotational direction and rotational speed is performed by a transmission system shown in FIG. 14. In the figure, reference numeral 68 denotes a drive gear that integrally includes a plurality of gears, and this drive gear 68 is rotated at a constant speed in a fixed direction, for example, in the direction of arrow H in the figure, via an intermediate gear (not shown) by a motor that rotates at a constant speed. do. 69
is a hammer gear that drives the hammer 47; 70 is a paper feed gear that drives the paper feed port 50; 71 is a reset gear that drives the reset cam; and 72 is the rotating shaft 2.
Of these, the rotary gear 72 is always meshed with the drive gear 68 at a predetermined tooth ratio and rotates at a constant speed in the direction of the arrow ■ in the figure, and the remaining hammer gear 691 is a paper feed gear. 70 and the reset gear 71 are intermittently meshed with the drive gear 68 at a predetermined tooth ratio, and only when the drive gear 68 is at a predetermined angular position, arrows J and K in the figure, respectively.
.

Rotate in the L direction.

Further, 73 is a sun gear integral with the rotating shaft 1, 74 is three planet gears that are circumscribed and meshed with this sun gear 73, 75 is a carrier shaft that pivotally supports these planet gears 74, and 76 is a carrier shaft for supporting these planet gears 74. A carrier 77 integral with the carrier shaft 75 is a ring gear that circumscribes and meshes with the planet gear 74, and these sun gears 73. Planet gear 74, carrier 76, and ring gear 77 constitute a known planetary gear train, of which carrier 76 and ring gear 77 are on the input side, and sun gear 73 is on the output side. 78 is such a planetary gear train and the drive gear 68
a selection gear interposed between the selection gear 7 and the selection gear 7;
Reference numeral 8 integrally includes three gears having different numbers of teeth, and two of the gears intermittently mesh with the driving gear 6B to rotate or stop in the direction of arrow M in the figure at a predetermined timing. That is, this selection gear 78 rotates at a low speed when the majority gear meshes with the drive gear 68, rotates at high speed when the minority gear of the selection gear 78 meshes with the drive gear 68, and further rotates at a high speed when the minority gear of the selection gear 78 meshes with the drive gear 68. and drive gear 6
It is designed to stop when it is engaged with the arcuate protrusions No. 8 (none of which are shown).

The rotational force of the selection gear 78 configured in this way is transmitted to the ring gear 77 by the remaining gears of the selection gear 7B meshing with the ring gear 77, and the rotational force is transmitted to the first ring gear 77.
It is selectively transmitted to the carrier 76 via a pawl clutch mechanism shown in FIG.

In FIG. 15, 79 is a rotation support shaft for the selection gear 78 and a rotating body 82 to be described later, and 80 is a drive shaft that rotates together with the selection gear 78. A notch 81 is formed on the circumferential surface of the drive shaft. . The rotating body 82 is loosely fitted to the rotation support shaft 79, and the carrier 76 of the planetary gear train described above is mounted on the circumferential surface of the rotating body 82.
A support shaft 84 and an engagement shaft 85 are provided upright at a predetermined interval. 86 is a drive pawl that transmits the rotational force of the drive shaft 80, that is, the rotational force of the selection gear 78 rotated by the motor, to the rotating body 82;
The drive claw 82 includes a first arm portion 88 having a projection 87 that is rigid and can be engaged with the cutout portion 81 of the drive shaft 80;
a second arm part 90 having elasticity and a sliding part 89 that comes into elastic contact with the engagement shaft 85 of the rotating body 82;
The base of the arm portion 88 is rotatably inserted into the support shaft 84 of the rotating body 82. Reference numeral 91 indicates a selection lever that is rotatable about a shaft 92, and 93 is a solenoid having an actuator 94. This solenoid 93 moves the selection lever 91 to an engagement position opposite to the drive pawl 86, and to a corresponding drive position. It can be switched to two positions: a non-engaged position where the claw 86 is out of the rotation locus.

In the pawl clutch mechanism configured in this way, first,
As shown in FIG. 15(a), the notch 81 of the drive shaft 80
When the protrusion 87 of the drive claw 86 is engaged with the solenoid 93, the solenoid 93 is energized, and the actuator 9
4 holds the selection lever 91 in a non-engaging position with the drive claw 86, and when the selection rotation shaft 79 and the drive shaft 80 rotate in the direction of arrow M in the figure as the gear 78 rotates,
Due to the engagement between the notch 81 and the protrusion 87 of the drive claw 86, the drive shaft 80 and the rotating body 82 rotate together in the direction of arrow M in the figure. The rotational force of this rotating body 82 is transmitted to the carrier 76 that meshes with the toothed portion 83, and the carrier 76 is connected to the arrow N in the figure.
Rotate in the direction. At this time, the rotational power of the selection gear 780 rotating in synchronization with the drive shaft 80 is transmitted to the ring gear 77, the planet gear 74, and the sun gear 73, as described above, and therefore, in this case, the rotational force of the motor is The carrier 7, which is the two input shafts of the planetary gear train, is
6 and ring gear 77, and the sun gear 73, which is the output side of the planetary gear train, rotates, for example, in the direction of arrow P in FIG. can do.

On the contrary, when it is desired to rotate the rotary shaft 1 in the direction of the arrow Q in FIG.
The selection lever 91 rotates in the direction of arrow R in Fig. 5(a).
As shown in FIG. 15(b), the drive claw 86 is held in an engagement position where it can face the drive claw 86. In this state, when the rotating body 82 rotates together with the drive shaft 80 in the direction M in the figure, the tip of the first arm 88 of the drive claw 86 moves to the guide portion 95 provided at the tip of the selection lever 91! The drive shaft 80 is brought into contact with the
As the first arm portion 88 rotates, the first arm portion 88 is guided by the guide portion 95 and moves outward.
is expanded against the spring force of the arm portion 90 of the first arm portion 88, thereby disengaging the protrusion 87 of the first arm portion 88 from the notch portion 8 of the drive portion 80, and the rotation of the rotational force of the drive shaft 80 is released. Transmission to body 82 is cut off. Therefore, in this case, the rotational force of the motor is transmitted via the selection gear 78 to the ring gear 77, which is the input shaft of one of the two human power shafts of the planetary gear train, but is not transmitted to the carrier 76, which is the other input shaft. Sun gear 7
3 and the rotating shaft 1 integrated therewith rotate in the direction of the arrow Q in FIG. In this embodiment, the ratio of the number of teeth is set so that forward and reverse rotations occur at the same speed ratio.

In the embodiment configured as described above, the following operations are basically performed by driving the motor.

<Inking> As shown in FIG. 1, when the protrusion 21 of the drive pawl 20 is engaged with the notch 3 or 4 of the drive shaft 2, the type wheel 5 is moved as the drive shaft 2 rotates. When the cam rotates in a predetermined direction, the switching cam 65 shown in FIG.
During rotation, the first ink roll 59 is pressed against the first type body 7 of the type wheel 5, and the second ink roll 60 is pressed against the second type body 7'. That is, for example, when printing in red, 1, arrow F in FIG. 11(a) of drive shaft 2
Approximately in the first half turn of the direction, the red ink of the first ink roll 59 is applied to the first type body 7 of the type wheel 5, thus applying the red ink to the first type body 7. The type wheel 5 performs a type selection operation, which will be described later, by approximately half a rotation of the drive shaft 2, and selects a desired type 7.
is positioned at the printing position. On the other hand, driving l1il! +
2 rotates in the opposite direction to that described above, the black ink of the second ink roll EiO is applied to the second type body 7' of the type wheel 5 during about the first half rotation of the drive shaft 2; With approximately half a subsequent revolution of the drive shaft 2, the desired type body 7' coated with black ink is selected in one position.

<Type selection> Once the desired ink has been applied to the type body 7 or 7' in this way during the first half-turn of the drive shaft 2, each type wheel 5 is moved during the subsequent half-turn of the drive shaft 2. is stopped at the desired position and the desired typeface 7.7' is moved by the hammer 4.
The printing position opposite to 7 is selected. Since this type selection operation has been described above, detailed explanation will be omitted here.

Depending on the use, there are type wheels that do not require type selection, but type wheel 5 where type selection was not performed
This is because the engaging convex portion 14 of the selection ratchet 6 always engages with the claw portion 26 of the selection claw 25 at a predetermined position during one rotation.
At this position, the transmission of rotational force from the drive shaft 2 to the selection ratchet 6 and the type wheel 5 is cut off and stopped. At this time, the locking operation by the selection claw 25 of the selection ratchet 6 is automatically performed by the engagement convex portion 14 of the selection ratchet 6 and the claw portion 26 at the tip of the selection claw 25, so that the Thus, there is no need to energize the electromagnetic clutch 31, and its power consumption can be reduced.

The stop position of the type wheel 5 where no type selection has been made is, for example, the position shown in FIG. Located in

As is clear from the above description, when the drive shaft 2 rotates, for example, approximately 180 degrees clockwise in the figure from the initial state shown in FIG. The type body 7' is coated, and during the subsequent rotation of the drive shaft 2 for about half a turn, that is, from 180 to 360 degrees counted from the initial state, the desired type wheel 5 is stopped and the type body 7' is selected. The type wheel is also stopped if no type selection was made at the end of its rotation. When inking and character selection are performed in about one rotation of the drive shaft 2 in this manner, the drive shaft 2 is stopped and the printing operation continues.

Further, when the drive shaft 2 rotates about one rotation in the counterclockwise direction in the figure from the initial state shown in FIG. 1, red ink is applied to the type body 7 of the type wheel 5 during the rotation, and The selection of the type on the type wheel 5 coated with ink takes place in a similar manner.

Printing> The printed characters 7 or 7' of the selected character wheel 5 face the protruding part 58 of the hole 57 of the error printing prevention body 48, and protrude from the protruding part 58 in the direction of the hammer 47 ( As for the type wheel 5 for which no type has been selected, the blank portion without the type body 7, 7' faces the protrusion 58, as shown in FIG. On the other hand, recording paper (not shown) is
The rotation of the paper feed roller 50 and the driven roller 51 causes the paper to be conveyed along the paper guide 49 onto the erroneous printing prevention plate 48, and when the hammer 47 rotates counterclockwise in FIG. The pressing portion 52 presses the recording paper against the selected type body 7° 7' of the type wheel 5, and one line of printing is performed. In addition, as mentioned above, the hammer 47
Although the pressing portion 52 is highly flexible, its surface is hard and is separated for each digit of the type wheel 5, so that clear characters are printed on the recording paper.

During the above typesetting operation, the type wheel 5, which is stopped at the printing position, receives a rotational force in a predetermined direction when it comes into contact with the rotating hammer 47. It is designed so that it does not shift. This will be explained below with reference to FIGS. 5(b) and 5(c).

FIG. 5(b) shows that, as described above, the engagement between the notch 3 of the drive shaft 2 rotating in the direction of arrow A and the protrusion 21 of the drive pawl 20 is released, and the type wheel 5 is stopped at the type position. In other words, the type is selected. in this case,
The selection ratchet 6 has its tooth portion 13 connected to the pawl portion 2 of the selection pawl 25.
6, and the type wheel 5 has its engagement shaft 11 and support shaft 12 engaged with the ends of the engagement holes 18, 19 of the selection ratchet 6, so that the type wheel 5 is engaged with the hammer 47 in this state. Even if a rotational force in the direction of arrow A is applied from , the type wheel 5 does not rotate. That is, if the rotation directions of the drive shaft 2 and the hammer 47 are different, in other words, the hammer 7
47 and the direction of rotation of the drive shaft 2 are the same, the type wheel 5 has its engagement shaft 11 and support shaft 12 engaged by the selection pawl 25. The selected engagement holes 18, 19 . :,
This locking restricts rotation and holds the print position.

If the rotation direction of the drive shaft 2 is opposite to this, that is, the fifth
As shown in Figure (c), the drive shaft 2 rotates in the direction of the arrow.
When the engagement between the notch 3 and the protrusion 21 of the drive pawl 2 is released, the pawl 26 of the selection pawl 25 passes between the teeth 13 of the selection latch 6 and locks the type wheel 5. It comes into engagement with the groove 8. By locking the type wheel 5 with the selection pawl 25 in this way, even if a rotational force in the direction of the arrow A, which is opposite to the direction indicated by the arrow, is applied from the hammer 17 of the type wheel 5 in this state, the type wheel 5 does not rotate. If the lock groove 8 of the type wheel 5 is not locked by the selection claw 25 in the state shown in FIG. 5(c), if the type wheel 5 receives a rotational force in the direction of the arrow, , engagement hole 1 of selection ratchet 6
8.19 and the engagement shaft 11 and support shaft 12 of the type wheel 5
Although the rotation of the type wheel 5 is restricted due to the engagement with the type wheel 5, when the type wheel 5 receives rotational force in the direction of the arrow A, the engagement shaft 11 and the support by the engagement holes 18 and 19 are The shaft 12 is not regulated and the type wheel 5 is moved in the direction of arrow A.
It rotates slightly in the direction, that is, by the clearance between the engagement shaft 11 and the support shaft 12 and the engagement holes 18 and 19. Therefore, when the rotation directions of the drive shaft 2 and the hammer 47 are the same, in other words, when the direction of the rotational force applied to the type wheel 5 by the hammer 47 is different from the rotation direction of the drive shaft 2, the type wheel 5 will not lock. II8 is the selection claw 25
Rotation is restricted by being locked by and held at the printing position.

<Reset> When the printing operation is completed as described above, the drive shaft 2, which had stopped during printing, starts to rotate about half a turn again in the same direction, that is, 360 to 540 degrees when counted from the initial state.
In addition, the tooth portion 13 or the locking convex portion 14 of the selection ratchet 6
All the selection claws 25 that were locked with the reset cam 2
9 rotates it to the standby state. That is, when the reset cam 29 rotates counterclockwise in FIG.
The selection pawl 25 that is engaged with the selection pawl 25 rotates in the direction of arrow C when the cam pawl 30 rides on the convex portion 46 from the stepped portion 45 of the reset cam 29, and thereby the selection pawl 25 and the selection pawl 26 of the selection pawl 25 are rotated. The engagement with the teeth 13 of the ranaette 6 is released. This operation is performed simultaneously for the selection pawls 25 attached to all the type wheels 5, and not only the selection pawls 25 that are engaged with the teeth 13 of the selection ratchet 6 as described above but also the selection pawls 25 that are engaged with the teeth 13 of the selection ratchet 6 as described above. The selection claws that were engaged with the mating convex portions 14 are also released from engagement, and all the selection claws 25 are held in a standby state by the reset cam 29 and the pressing spring 33. Note that the angular position of the type wheel 5 of each digit that is stopped at the printing position varies depending on the type selected, and for example, the type wheel 5 where no type is selected rotates approximately one rotation from the initial state. However, the type wheel 5 whose type is selected is stopped at a smaller angular position.

In this way, when the locking state of the selection ratchet 6 by the selection pawl 25 is released, the type wheel 5 and the selection ratchet 6 that had been locked at the printing position until then are moved by the drive pawl 21 through the notch in the drive shaft 2. By coming into elastic contact with the circumferential surface of the portion 3.degree.4, it rotates integrally with the drive shaft 2. When the engaging protrusion 96 provided on the outer periphery of the type wheel 5 comes into contact with the claw part 26 of the selection claw 25 in the standby state, %IXI
Since the transmission force of the rotational force of the JI shaft 2 to the type wheel 5 is only the spring pressure of the drive pawl 20 and is very small, the type wheel 5 and the selection ratchet 6 stop at the position, and the drive shaft 2 continues to be transmitted. During the rotation, the protrusion 21 of the drive claw 20 slips on the circumferential surface of the drive shaft 2. Since one of the engaging protrusions 96 is provided at a desired position on each type wheel 5, specifically at a position outside the locking convex part 14 of the selection ratchet 6, the rotation angle thereof will vary at the printing position. Each type wheel 5 has an engaging protrusion 96 as described above.
is locked by the selection claw 25, so that the digits are all aligned at a constant angular position of +13, that is, approximately one rotation from the initial state.

When the engaging protrusions 96 of the type wheel 5 of all digits are engaged with the selection claws 25 in this way, the protrusions 21 of the drive claw 2 are reengaged with either one of the notches 3.4 of the drive shaft 2. match. In this case, as mentioned above, the rotation angle from the initial state is
While the drive shaft 2 rotates approximately 1.5 revolutions, the type wheel 52, selection ratchet 6, and drive pawl 20 rotate approximately 1 revolution. The protrusion 21 of the drive pawl 20 that has been in the position engages with the other notch 4 of the drive shaft 2 at the reset position. Then, when the drive shaft 2 continues to rotate by a certain amount, that is, approximately 1.5 revolutions counted from the initial state, each type wheel 5 and selection ratchet 6 rotate integrally with the drive shaft 2, and at this time The rotation transmission force of the drive shaft 2 to the type wheel 5 is very large due to the engagement between the protrusion 21 of the drive claw 20 and the notches 3 and 4 of the drive shaft. The type wheel 5 is rotated outwardly against the spring force of the pressing spring 33 by the engaging protrusion 96 of the type wheel 5, which rotates integrally with the type wheel 5, that is, the claw 26 of the selection claw 25 rides over the engaging protrusion 96, as shown in FIG. At this position, as the drive shaft 2 stops rotating, the type wheel 5 and selection ratchet 6 also stop.

<Paper Feed> When the printing operation is completed, the paper feed roller 50 is rotated counterclockwise in FIG. 1 in parallel with the reset operation, and the rotation of the paper feed roller 50 causes the paper feed roller to The recording paper held between the roller 50 and the driven roller 51 is conveyed by a predetermined amount.

Each operation explained above, ie, <inking>.

Type selection>, <Printing>, <Rinatsu 1. >, <Paper feed>
Through these operations, printing for one line is performed, and by repeating this process, desired printing is performed. Then, by selecting the direction of rotation of the drive shaft 2, that is, by selecting the direction of rotation of the drive shaft 2 between forward and reverse using the pawl clutch mechanism shown in FIG. 15, as described above. , you can choose between red printing and black printing.

In this way, in the above embodiment, the power supply latch 3
1 and selects the selection pawl 25 by selecting the teeth 13 of the ratchet 6.
By engaging with the selection ratchet 6, not only can a desired type selection be performed, but also when selection of type is not necessary or when only paper feeding is performed, the locking protrusion 14 of the selection ratchet 6 can be
The type wheel 5 can be similarly locked in a predetermined position by engaging with the selection pawl 25 which is in the rotational trajectory and is in a standby state without being energized.
The type wheel 5 can be locked at times other than when type is selected without energizing the electromagnetic clutch 31.

In the above embodiment, the electromagnetic clutch 31 is used as an example of the driving means for driving the selection pawl 25, but a solenoid may be used instead.

(Effects of the Invention) As explained above, according to the printer according to the present invention,
Since the type wheel that does not require type selection can be locked in a predetermined position by the engagement of the selection pawl in the standby state with the selection ratchet 1-○ IE convex portion, it is possible to energize the drive source of the selection pawl in these cases. is not required, which not only reduces power consumption, but also prevents the drive claw from coming off the drive shaft during high-speed rotation even if the spring force of the drive claw that transmits power from the drive shaft to the type wheel is set to a small value. Therefore, it becomes easier to downsize the motor that drives the drive shaft and to attach the drive claw to the type wheel.

[Brief explanation of drawings]

The figures all relate to one embodiment of the present invention, in which Figure 1 is a schematic side view of the printer, Figure 2 is a front view of the type wheel, Figure 3 is a front view of the selection ratchet, and Figure 4 is the type wheel and selection. An exploded perspective view showing the relationship between the ratchet, the drive pawl 1 selection pawl, and the electromagnetic clutch, FIG.
1 is an explanatory diagram showing the engagement relationship between the selection ratchet and the selection pawl, FIG. 7 fat is a plan view of the hammer, and FIG.
8 is a plan view of the printing error prevention plate, FIG. 9 is a perspective view of the roll holder and ink roll, FIG. 10 is a perspective view of the switching cam, and FIG. Figures fa) to E
el is an explanatory diagram showing the engagement relationship between the roll holder and the switching cam, FIGS. FIG. 14 is a timing chart showing the relationship between each operation during the printing operation; FIG. 14 is an explanatory diagram showing an outline of the operation transmission system;
Figure 5 (bl is an explanatory diagram of the pawl clutch mechanism provided in the power transmission system. 1...rotating shaft, 2... drive shaft, 3.4
...Notch, 5,5' ...Type wheel, 6,6゛ ...Selection ratchet, 7.7
'...Printed font, 8...Lock groove, 11
．． 11'...Engagement shaft, 12.12'...
...Spindle, 13.13'...Tooth, 14.14
'...Locking protrusion, 16.17...Release pin, 18°18', 19.19'...Engagement hole, 20.20'... ...Drive claw, 21.21'
...Protrusion, 22.22'...First arm part, 23.23'...Sliding part, 24°24'
...Second arm, 25.25' ...
・Selection claw, 26.26'...Claw part, 27...
... Rotation axis, 29 ... Reset cam, 30
．． 30'...Cam pawl, 31...Electromagnetic clutch, 32...Latching spring, 33...
・Press spring, 34... Electromagnetic coil, 36...
...Yoke, 45...Step drop, 46...
...Protrusion, 47...Hammer, 48...
- Erroneous printing prevention plate, 52... Pressing part, 53...
...Notch, 54...Gap, 57...
- Hole, 58... Protrusion, 59... First
ink roll, 60... second ink roll, 61... roll holder, 62... spindle, 63... first cam claw , 64...
Second cam pawl, 65...Switching cam, 66...
...First cam groove, 67... Second cam groove, 68... Drive gear, 69... Hammer gear, 72... Rotating gear, 73... Sun gear, 74... Planet gear, 75...
... Career axis, 76 ... Career, 77.
...Ring gear, 78...Selection gear, 7
9... Rotation support shaft, 80... Drive shaft,
81... Notch, 82... Rotating body, 8
3...Tooth portion, 85...Engagement shaft, 86...
...Drive claw, 87...Protrusion, 88...
...First arm, 90...Second arm, 91
... Selection lever, 93 ... Solenoid, 95 ... Guide portion, 96 ... Engagement protrusion. Sai2ji7'/! , L9i age 3 figure 75 floor ta) 2nd order (C) ri7, do''>>''' ○ /z2 Katana, 1 pivot p ,, l' 3 4 1 Schiff,...,...' age 6 trouble (/j) ffi, l :M 77th grade β n -111, 4,

Claims (1)

[Claims] A drive shaft having a notch on the circumferential side, a type wheel rotatably attached to the drive shaft and having a type body on the circumferential side, and a type wheel held by the type wheel and capable of engaging with the notch of the drive shaft. a driving pawl having a protrusion; a driving pawl rotatably attached to the type wheel via the driving pawl; an engaging portion that can be engaged with the driving pawl; A selection latch having a locking protrusion, a selection pawl capable of locking rotation of the selection ratchet by engaging with these teeth and the locking protrusion, and a driving means for driving the selection pawl,
When selecting type, the selection pawl in a standby state is driven in the direction of engagement with the teeth and locks the selection ratchet, thereby causing the engaging portion of the selection ratchet to engage with the drive pawl. If the engagement between the protrusion of the drive claw and the notch of the drive shaft is released and the type selection is not performed,
When the locking protrusion engages with the selection pawl in a standby state, the selection ratchet is locked and the engagement between the protrusion of the drive pawl and the notch of the drive shaft is released. printer.