JPH02258273A - Printing device - Google Patents

Abstract

PURPOSE:To control the engagement of an electromagnetic trigger member with a switching member and switch among functions such as selection, printing, taking a figure up one position and returning a carriage to a home position by using a single motor and a single electromagnetic member, and controlling the range in which the electromagnetic trigger member is energized. CONSTITUTION:A motor gear 7 rotates in an arrow J direction by rotation of a motor 6 to rotate a reduction gear 8 and a planetary gear 10 in arrow K, L directions. In addition, a type shaft 22, a trigger drive gear 37, a trigger planetary gear 24, a brake gear 26, a brake disc 27 and a type holder 53 rotate. Types are selected by controlling the power supply to a coil 29 using a type position signal generated for appropriate types 50a. If the coil 29 is energized, the brake disc 27 is attracted to the 28 of an electromagnetic brake and its rotation stops. However, yoke the trigger planetary gear 24 keeps rotating, and a trigger lever 23 rotates in an arrow C direction. Consequently, a selection ratchet 21b becomes engaged with the type shaft 22 and the type holder 53, and these stop, resulting the stoppage of desired types 50a on the surface opposite to a platen 44 with a discontinued type selection.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a serial printing device that performs printing by moving a type member in the digit direction. The present invention relates to a small-sized printing device that can be used for pocket trains, etc., and performs selective printing of type by alternately switching a second output.

Conventional examples of controlling selective printing using a differential mechanism in a conversion mechanism that can alternately output the first and second outputs include the apparatus described in Japanese Patent Publication No. 48-13365 and Japanese Patent Publication No. 112617-1971. can be raised. However, in both cases, a type member, a printing mechanism, and a selection mechanism are mounted on the carriage, and the selection electromagnetic Hfl is also arranged on the carriage. Raising the water bar, feeding the paper, and returning the carriage each require separate power sources, making the device complicated, large, and expensive, and cannot be used in a printing device for pocket calculators.
Further, as a conventional example of a serial printing device for a small calculator, there is a device described in Japanese Patent Laid-Open No. 52-46930. However, this device not only has a complicated mechanism, but also uses a large electromagnetic plunger to raise the print carry and return the paper feed carriage, and also uses a pulse motor to select the type, so it has a large appearance. Moreover, the price was also high.

The present invention eliminates these drawbacks, and its purpose is to control all operations necessary for a printing device with one motor and one electromagnetic member.

Another object of the present invention is to control all operations with one motor and one electromagnetic member, thereby significantly reducing the number of parts and creating a compact, lightweight, and inexpensive printing device.

Still another object of the present invention is to simplify the control circuit controlling the printing device tG III.

An embodiment of the present invention will be explained using figures.

FIG. 1 is a plan sectional view, and is composed of a selection mechanism 1, a paper feed and carriage return mechanism 2, and a carriage 3.

Fig. 2 is a side view of the selection machine IM 1, Fig. 3 is a side view of the paper feed and carriage return mechanism 2, and Fig. 4 is a perspective view of the selection mechanism 1, paper feed and carriage return mechanism 2. Arrow A
It is a figure seen from the direction lower surface.

An overview of each mechanism will be explained.

(1) Motor 6 fixed to selection mechanism frame 5, motor gear 7 fixed to motor shaft 6a, gear 8 meshing with motor gear 7
a, shaft portion 8b bearing the selection drive gear 9, planetary gear lO
A reduction gear 8 consisting of a sun gear 8c meshing with the gear 8 and a selection drive gear 9 have a shaft 9a that supports a planetary gear 1°. The printing 1i71 conversion cam 11 is the internal gear 1 that meshes with the planetary gear 10.
1a, claw 1 of the selection claw 12 (Fig. 2.4) which is a locking member
A cam 1 having a notch 11b on the outer periphery that engages with the cam 2a.
A protrusion l on the outer periphery that engages with the claw 12b of the 1C1 selection claw 12.
cam 11, which is a control member that engages with part 13a of the positioning lever 13 (FIGS. 3 and 4) which is a switching member, and a printing gear 15 fixed to the printing shaft 14 in a one-to-one mesh. It consists of a gear 11g. The reduction gear 8 and the printing switching cam 11 are connected to the shaft 1 which is mounted between the frames 5 and 16.
It is supported by a shaft at 7. Sun gear 8c, planetary gear 10
, the internal gear 11a and the selection drive tooth Ill 9 constitute a differential mechanism which is a conversion mechanism using planetary gears. 0 selection tooth It that is biased in the B direction! 21 meshes with the selection drive gear 9, and the selection pawl 12
Teeth 2 regularly arranged on the outer periphery that engage with the claws 12c of the
1a (i) with a selected windmill 21b and a frame 16.
It is fixed to a type shaft 22 which is mounted between 18 and 18. The trigger lever 23 has a shaft 23a that supports the trigger planetary gear 24;
The type shaft 22 consists of a portion 23b that engages with a portion 12d of the selection claw 12 and a portion 23c that engages with a portion 13b of the positioning lever 13.
It is pivoted to and biased in the direction of arrow C by a spring 25. The trigger sun gear 37 is integrally formed with the paper feed clutch windmill 37a and is fixed to the type shaft 22. Brake 1i
26 is trigger play! It has a pin 26a that meshes with the wheel 24 and engages with a hole 27a provided in a brake Mi 27 made of ink. The electromagnetic brake yoke 28 is made of a magnetic material, has an opening 28a facing the moving disk 27, and has a coil 29 disposed inside. Braking gear 26, Luri moving disc 2
7. The electromagnetic brake *i28 is supported by a shaft 32 mounted on a frame 30.31, and the electromagnetic brake yoke is fixed to the frame 31 in a non-rotatable manner. Is it an electromagnetic component? lXlX--K is constituted by 41+1 electromagnetic brake m iron 28, braking disk 27, and coil 29.

The selection mechanism 1 is configured by the above elements.

(2) Paper feeding and carriage 1u return mechanism The positioning lever 13 has a portion 13a that engages with the cam 11f of the print switching cam 11, a portion 13b that engages with a portion 23C of the trigger lever 23, and a portion 13a that supports the paper feed trigger lever 33. , a portion 13a that engages with a portion 33a of the paper feed trigger lever 33, and a protrusion 13e that engages with a protrusion 34a of the positioning transmission lever 34, which is a connecting member.
The paper feed trigger lever 33 is biased in the direction of the arrow E by a spring 36, and the paper feed trigger lever 33 is biased in the direction of the arrow E by a spring 36. The paper feed clutch pawl 35 has a gear 38a that meshes with a paper feed transmission tooth 39, and is supported on a shaft 38b provided with a paper feed wA moving gear 38 which is rotatably connected to the type shaft 22. It is biased in the direction of arrow F by a spring 40 fixed to the feed drive gear 38. Furthermore, the paper feed clutch pawl 35 has teeth 37b regularly arranged on its outer periphery.The paper feed gear 47 has a pawl 35b that meshes with teeth 37b of a paper feed clutch pinwheel 37a.
The zero positioning transmission lever 34 is fixed to the fixed shaft 48 and meshes with the paper feed transmission gear 39 which is supported on the shaft 66 which is mounted on the frame 30° 43.
5a, and a portion 34a that engages with a portion 41b of a positioning plate 41 which is supported on the shaft 19 and has a plurality of 41a in a part thereof and is biased in the direction of arrow Q by a spring 46. It is biased in the direction of arrow Gh by a compression spring 42 (FIG. 5).

The paper feeding and carriage return mechanism 2 is configured by the above-mentioned elements.

(3) The type belt 50 which has the type 50a on the outer periphery of the carriage and the protrusion 50b inside the type 50a, the type belt 51 which has the type 51a and the protrusion 51b, and the type belt 52 which has the type 52a and the protrusion 52b are type Shaft 22 has sliding function i1, rotor t
It is attached to a type holder 53 attached to U (m).
Holes are provided so that the protrusions 50b, 51b, and 52b of 0.0, 51.52, respectively, are loosely fitted. The type belt 50°51.52 is made of an elastic material such as rubber. The type holder 53 is held by the carriage frame 54 so as to be movable by a constant m, and is biased by a type spring 65 in the opposite direction of arrow H. The carriage frame 54 is the type shaft 2
2. Guided by the printing shaft 14 and moved in the direction of arrow H i'r
It is K. The hammer 55 is supported on a shaft 54a provided on the carriage frame 54, and is biased in the direction of the arrow by a spring 56.
A portion 55a engages with an end surface 57a of a printing cam 57 which is held between the printing shaft 14 and slidably but not rotatably mounted on the printing shaft 14. Furthermore, the other end 55b is the type belt 50 or 51.
．． It is disposed so as to engage with the protrusion 50b or 51b, 52,b of 52. Positioning on the outer periphery @41 of @4
A carry cam 58 having a single cam 58a that meshes with the cam 1a is held between 54d and 54e of the carriage frame 54, and is attached to the print shaft 14 so that the rotor can rotate and slide (m).

The carriage 3 is composed of the above elements.

Next, a series of operations will be explained.

(1) Initial settings Perform initial settings before starting selection and printing.

The carry cam 58 and the tooth 4 of the positioning plate 41 are
1a (FIG. 10), the direction is changed by a spring guide roller 62 which is supported on a shaft 61 fixed at one end to a section 54f of the carriage frame 54, and the other end is fixed to a frame bottom plate 60, and the frame is rotated. A return spring 63 attached to a spring hook 59 provided on the bottom plate 60 and biasing the carriage 3 in the direction opposite to the arrow H moves the carriage 3 in the direction opposite to the arrow H and fixes the 54g portion of the carriage frame 54 to the frame 18. At this time, part 53a of the type holder 53 also comes into contact with the carriage I collar 64, and moves within the carriage frame 54 while compressing the type spring 65, and 55b of the hammer 55 is brought into contact with the carriage stopper 64 (FIG. 1). The part stops at a position corresponding to the type belt 50.

The type spring 65 is set to be weaker than the return spring 63. The spring 20 causes the claw 12a to lock the notch llb of the cam lie, and the claw 12c locks the tooth 2 of the selection type wheel 21.
Trigger lever 2 runs away from 1a (solid line in Figure 1'12)
3, the part 23a is positioned by the spring 25 and the part 13 of the bar 13 is
It waits at the position where it touches part b (solid line in Figures 2 and 3).

(2) Selection of -th digit Rotation of the motor 6 causes the motor teeth 1117 to rotate in the direction of arrow J, causing the reduction gear 8 and the planetary gear 10 to move in the direction of the arrow, respectively.
Rotate in the L direction. At this time, the print switching cam 11 is
2a, the internal gear 11a cannot rotate. Since the internal gear 11a cannot rotate, the planetary gear 10 revolves around the sun gear 8C while rotating, and moves the selection drive gear 9 in the direction of the arrow via the planetary shaft 9a. The rotation of the first selection drive gear 9 rotates the selection gear 21 in the direction of arrow O, and further rotates the type shaft 22, the trigger drive gear 37, and the trigger planetary gear 24.
, the brake gear 26, the brake disc 27, and the type holder 53 are rotated. The desired type is selected by a well-known method.
The desired type is detected in the frame 18.43 by controlling the energization of the coil 29 using a type position signal generated by a detection means (not shown) that generates a type position signal in response to a.
The coil 2 is placed slightly before facing the platen 44 mounted on the
9 is energized. When the coil 29 is energized, the brake disc 27
is attracted to the electromagnetic brake yoke 28 and the electromagnetic brake yoke 2
8 is a rotation rate ii1 (IP), so the rotation of the brake disc 27 is stopped. When the rotation of the brake 1slli 27 is stopped, the rotation of the brake gear 26, which is locked by the pin 28a, is also stopped. Brake gear 26 Even if the rotation of the trigger planetary gear 2 stops
4 continues to rotate, it rotates on the trigger driving vehicle 37 in the direction of arrow N and revolves in the direction of arrow C opposite to arrow C, and rotates the trigger lever 23 through the shaft 23a in the direction of arrow C opposite to the direction of arrow C while countering the spring force of the spring 25. let The rotation of the trigger lever 23 is 23
The selection claw 12 is rotated in the direction of arrow B by the part b, and the selection claw 12 is
c is meshed with the teeth 21a of the selection type wheel 21b, and the selection type wheel 21
When the 0-selection pinwheel 21b is locked (dashed line in Figure 2), the rotation of the type shaft 22 and type holder 53 is also stopped, and the desired type 50a is stopped on the opposite surface of the platen 44, and the selection is completed. (Figure 6).

(3) When the first digit is printed and the carry trigger lever 23 rotates, the selection pawl 12 rotates in the opposite direction of arrow B to select the desired type, and at the same time the pawl 12a and notch llb are disengaged and the print switching cam 11 rotation becomes free. At this time, since the rotation of the selection type wheel 21b is stopped by the pawl 12c, the rotation of the selection gear 21 and the selection drive gear 9 is also stopped.

Therefore, the rotation of the planetary gear 10 causes the print switching cam 11 to rotate in the direction of arrow P due to the internal teeth l1la. The printing switching cam 11 is rotated by the printing gear 15, the printing shaft 14, and the printing cam 57.
, rotates the carry cam 58.

When the printing cam 57 rotates, the cam lead on the cam end surface 57a rotates the hammer 55 in the direction opposite to the direction of the arrow.
55b engages with the protruding portion 50b of the type belt 50, causing the type belt 50 to protrude from the inside and moving the type 50a onto the printing paper 4.
Ink is applied to the surface of the printed characters 50a by a well-known method using an ink roll or the like (not shown), which is pressed against the platen 44 through the printed characters 50a (double-dot chain line in FIG. 6). FIG. 7 shows a time chart of the operation of each element during one rotation of the printing 1tlJ exchange cam 11, that is, the printing shaft 14, 101 is the energization of the coil 29, 102 is the trigger lever 23, 103 is the operation of the selection claw 12, 104 is the rotation of the type shaft 22, 105
106 is the cam lead of the printing cam 57, 107 is the cam lead of the digit cam 58, 108 is the movement of the positioning transmission lever 34 in the direction of arrow G, and 109 is the positioning lever 13. 110 indicates the operation of the paper feed trigger lever 33, and 111 indicates the operation of the positioning plate 41. The coil 29 is energized until the print switching cam 11 starts rotating (solid line in FIG. 7), and the selection claw 12
The pawl 12a engages with the outer periphery of the cam LLC to maintain the operating state.The trigger lever 23 de-energizes the coil 29 and the brake disk 27 is free to rotate, so the trigger planetary gear 24 and brake are activated by the action of the spring 25. While rotating the gear 26 and the inner disk 27, they rotate in the direction of the arrow CJj and return to the standby state (solid line in Figure 2).

As soon as the printing gear [15 starts rotating, the printing gear 15
Positioning is carried out by the end cam 15a provided on the elm 3
4 moves in the opposite direction of the arrow G to move the protrusion 13 of the positioning lever 13.
The positioning plate 41, which is disengaged from the part e and becomes free to rotate and engages with the part 34c, is urged in the direction of the arrow Qh by the spring 46, so it rotates in the direction of the arrow Q, and the teeth 41a move toward the carry cam 5.
When the cam llf of the printing switching cam 11 that engages with the cam 58a of No. 8 (solid line in FIG. 10) rotates about 100'', the notch 11h corresponds to the portion 13a of the positioning lever 13, but the trigger lever 23 of the positioning lever 13 has already been Since it has returned to the standby state, the part 135 is locked by the part 23a and does not operate. Therefore, the protrusion 34a of the positioning transmission lever 34 and the protrusion 13e of the positioning lever 13 come into contact with each other, and the positioning transmission lever 34 is moved to the printing gear 15. Even if the cam 15a disappears, it does not move in the direction of arrow G, and the engagement between the teeth 41a of the positioning plate 41 and the cam 58a of the carry cam 58 is maintained.

When the printing shaft 14 rotates 180 parts to complete the printing operation and rotates further, the carry cam 58 moves in the direction of arrow H by the teeth 41a of the positioning plate 41 and the cam lead of the cam 58a.When the 0 carry cam 58 moves, the carry cam 58 moves. 58, a printing cam 57, and a hammer 55.
move at the same time, but there is a gap δ1 (Fig. 1) between the type holder 53 and the carriage frame 54, and although the carriage frame 54 moves, the type holder 53
5 keeps the portion 53a in contact with the carriage stopper 64 (FIG. 8). At this time, the portion 55b of the hammer 55 corresponds to the type belt 51. When the print switching cam 11 rotates approximately 330 degrees, the claw 12 is inserted into the notch llb.
Since "a" corresponds to "a", the selection claw 12 rotates in the direction of arrow B by the action of the spring 20 and locks the print switching cam 11 again, thereby completing printing and carrying. The projection lid of the cam lie of the print switching cam 11 and the pawl 12b engage when the notch llb starts, assisting the action of the spring 20, and causing the selection pawl 12 to rotate in the direction of arrow B.

(4) Selection of the second digit The selection pawl 12 rotates in the direction of arrow B and locks the print switching cam 11, and at the same time the pawl 12c and the selection type wheel 21b are unlatched, as detailed in the selection of the first digit above. So again select gear 2
1 rotates again and the desired type selection is made. At this time, the difference from the selection of the first digit is that in the first digit, the desired type to be selected is selected from the group of type provided on the type belt 50, but in the second digit, as shown in FIG. Selected from a set of characters provided.

(5) Printing of 2 digits [1 and carry printing are performed in the same manner as the printing of the first digit described in detail above. The difference is that for the first digit, the type belt 50 is protruded from the inside and pressed against the platen 44 to print, but for the second digit, the type belt 51 is protruded from the inside and pressed against the platen 44 as shown in FIG. To carry up the 0 digit, the holder 41a of the positioning plate 41 and the carry cam 5
The carriage 3 is moved in the direction of arrow H by the cam lead of the cam 58a. At this time, the difference from the previous time is that the gap δ2 between the type holder 53 and the carriage frame 54 is set to be slightly smaller than the carry pitch, so the type holder 53 comes into contact with the carriage frame 54 and moves slightly in the direction of arrow H, and the hammer 55 55b corresponds to the type belt 52 (FIG. 9).

(6) Selection of the third digit The selection is made in the same manner as the selection of the second digit. The difference from the second digit is that in the second digit, the characters selected are from the group of characters on the character belt 51, but in the third digit, they are selected from the group of characters on the character belt 52 (FIG. 9).

(7) Printing of the third digit and carry printing are done in the same way as for the second digit. The difference from the second digit is that the type that is projected from the inside and is pressed and printed on the platen 44 is a type from the group of type on the type belt 52.
It is done in the same way as the digit. The difference from the second digit is carriage 3.
moves by one digit, but since the type holder 53 and the carriage frame 54 are already in contact with each other at this time, they move in the state shown in FIG. 9 (the portion 55b of the hammer 55 corresponds to the type belt 52).

(8) Selection, printing, and carry after the 4th digit (as explained in detail above)
This is done by repeating steps 6) and (7).

(9) Selection of the uppermost digit of M, printing, paper feeding, and carriage return time chart (Figure 7) correspond to the two-dot chain line.Selection is made in the same way as before, but the coil is not energized immediately for the highest digit. The energization is maintained until the print switching cam 11 rotates approximately 145 degrees as shown by the dotted chain line at 10 in the time chart (FIG. 7). When the print switching cam 11 rotates lOO°, the notch llh of the cam 11f moves to 1 of the positioning lever 13.
Corresponds to part 3a.゛At this time, the trigger lever 23 is
9 is not turned off, so it is in operation (2nd, 3rd).
7) is maintained. Therefore, the positioning lever 13 is rotated in the direction of the arrow by a spring (not shown) (
3) When the positioning lever 13 rotates, the paper feed trigger lever 33 is also rotated in the opposite direction of arrow E by the 13a portion of the positioning lever 13, and the 33b portion and the 35a portion of the paper feed clutch pawl 35 are locked. When the zero paper feed clutch pawl 35 is released, it moves in the direction of arrow F due to the action of the spring 40.
direction, and the pawl 35b meshes with the teeth 37b of the paper feed clutch type wheel 37a (two-dot chain line in FIG. 3).

At this time, since the type shaft 22 has stopped rotating, the paper feed clutch type wheel 37a has also stopped rotating, but the teeth 37b correspond to the type 50a of the type belt 50, and the claw 35 at the stopped position
Since it is provided so as to mesh with the claw 35b and the tooth 37b
mesh. When the print switching cam 11 further rotates, the positioning lever 13 is rotated in the direction opposite to the arrow by the cam lead 111 of the cam llf and returns to the standby state.0 The paper feed trigger lever 33 is rotated in the direction of the arrow E by the spring 36, but the paper feed clutch claw 35 is in operation, the portion 33b comes into contact with the portion 35a of the paper feed clutch pawl 33 and stops. The carriage return is carried out as follows. When the zero positioning lever 13 rotates in the direction of the arrow, the protrusion 13e and the fourth part 13f of the positioning lever 13 face the fourth part 34d and the protrusion 34a of the positioning transmission lever 34, respectively. Print switching cam 11 is 145
@ When rotated, the lead of the end cam 15a of the printing gear 15 is lost, and the positioning transmission lever 34 moves in the direction of arrow G by the action of the spring 42, and the protrusion 13e of the positioning lever 13,
The four parts 13f mesh with the recess 34d and the protrusion 34a of the positioning transmission lever 34 (solid lines in Figure 5). When the printing switching cam 11 rotates about 190 degrees, the positioning lever 13 is rotated in the opposite direction of the arrow by the cam lead lli. Return to standby state. At this time, the positioning transmission lever 34 is engaged with the positioning lever 13, so it rotates in the direction opposite to the arrow mark.
Since it is engaged with part a, it is rotated in the opposite direction of the arrow Q, and the cam 58a of the carry cam 58 and the tooth 41a of the positioning plate 41 are kept in a disengaged state (double-dashed line in Fig. 10). )0 When the engagement between the positioning plate 41 and the carry cam 58 is released, the carriage 3 returns to the standby state (
The trigger lever 23 returns to the standby state by the action of the spring 25 when the coil 29 is de-energized.The printing ttJJ exchange cam 11 rotates once and the printing shaft 22 starts rotating again. Then, the paper feed clutch type wheel 37a also rotates.
5b are engaged, the paper feed drive gear 38, which supports the paper feed clutch pawl 35 and the paper feed clutch pawl 35 on the shaft 38b, also rotates in the direction of arrow R. 0 When the paper feed drive gear 38 rotates, the paper feed trigger lever 33 has its 33b portion abutted against the outer portion 7i9ff38c of the drive gear 38 due to the action of the spring 36.

When the paper feed drive gear 38 rotates once, the paper feed trigger lever 3
3 and 35a of the paper feed clutch pawl 35 are engaged again, and the paper feed clutch pawl 35 and the paper feed clutch type wheel 37 are engaged again.
The rotation of the paper feed drive gear 38 is stopped due to the disengagement with a.
The rotation of the paper feed drive gear 38 is caused by the paper feed gear 47, the paper feed shaft 48, and the paper feed roller 49 via the paper feed transmission gear 39.
is rotated, and the paper feed roller 49 feeds the printing paper 45 by one line.

If the next line is to be printed subsequently, steps (2) to (9) above may be repeated.

As explained above, according to the present invention, one motor and one electromagnetic member are used, and the engagement between the electromagnetic trigger member and the switching member (positioning lever 13) is controlled by controlling the energization width of the electromagnetic trigger member vi. You can perform selection, printing, carry, paper feed, and carriage return switching in an extremely simple manner. This can significantly reduce the number of parts, reduce assembly man-hours, simplify the analog control circuit that controls the printing device, and only need one electromagnetic member to drive. The number of drivers can be reduced, and not only can the printing device be made smaller, lighter, and cheaper, but when it is integrated into a calculator, it can also be made smaller, lighter, and cheaper.

[Brief explanation of drawings]

FIG. 1 is a plan sectional view of a printing apparatus according to the present invention, FIG. 2 is a side view of the selection mechanism, FIG. 3 is a side view of the paper feed and carriage return mechanism, and FIG. 4 is a side view of the selection mechanism, paper feed and carriage return. Fig. 5 is a plan sectional view of the carriage return mechanism, Fig. 6 is a side sectional view of the type member, Fig. 7 is a time chart, and Fig. 8 is a perspective view of the mechanism as seen from below in the direction of arrow A. FIG. 9 is a state diagram in which the carriage is in the second digit, FIG. 9 is a state diagram in which the carriage is in the third digit, and FIG. 10 is a side sectional view of the carry mechanism. 1... Selection mechanism 2... Paper feed carriage return m mechanism 3... Carriage 6... Motor 8... Reduction gear 55... Hammer 57... Print cam 58... Carry cam Applicant Seiko Epson Co., Ltd. Agent Patent attorney Kizobe Suzuki and 1 other person 9...Selection drive gear 10...Planetary gear 11...Print switching cam 12...Selection pawl 13...Positioning Lever 14... Printing shaft 21... Selection gear 22... Printing shaft 23... Trigger lever 27... Braking disc 28... Electromagnetic brake 1n iron 29... Coil 34... Positioning transmission Elevator 35...Paper feed clutch pawl 37a...Paper feed clutch type wheel 38...Paper feed drive gear 41...Positioning plate 50,51,52...Type belt 53...Type holder 54... ...Carriage frame Figure 6

Claims (1)

[Claims] a selection mechanism that converts the rotation of a motor into a first output and a second output; a type member on which type is rotatably driven by the first output; and the type on the type member driven by the second output. After selecting, a printing means for printing the type on printing paper, a locking member for alternately catching and locking the first output and the second output, and a printing means driven by the second output are connected to the upper layer. a digit-feeding mechanism that moves in the digit direction; a return member that returns the printing means to the lowest digit; a switching member that is connected to the digit-feeding mechanism and selects a digit-feeding state and a return state; and an electromagnetic means at least partially. a trigger means that engages with the switching member to regulate the position of the switching member; and a control member that engages with the switching member driven by the second output and regulates the position of the switching member. The control member holds the switching member in an inoperative state to put the shifting mechanism in a shifting state when the trigger means is in a first energized state, and the control member maintains the switching member in a non-operating state when the trigger means is in a first energized state, and when the trigger means is in a second energized state. 2. A printing apparatus characterized in that the shift mechanism is controlled to a return state by releasing and activating the switching member at the time of .