JPH0246391B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printing device, particularly a serial printer, and an object of the present invention is to provide a printing device that is small, lightweight, and capable of alphanumeric printing.

Recent calculators have become more multi-functional and sophisticated, and there are more types of input keys for scientific calculators, program calculators, etc. Therefore, as a printing device built into this type of calculator, it is desired to develop a printing device that is capable of alphanumeric printing and also performs matrix printing because the printed data is clear.

The present invention has been made in view of these points,
Examples will be described below with reference to figures.

FIG. 1 is a diagram for explaining the schematic configuration of a printing device. Between the side plates 1a and 1b, which are part of the frame of the printing device, a type wheel selection cam shaft 2, a type shaft 3, a print/carry shaft 4, and a rack 5 are installed in order from the front side as viewed in the figure. It is rotatably constructed at intervals of
Below the carry shaft 4 is a paper feed shaft 6 (see Figure 2).
is installed so that it can rotate.

The carriage 7, which is stretched between the type wheel selection cam shaft 2 and the type shaft 3, is held so as to be able to slide along these axial directions, and is moved to a home position (close to the side frame 1a) by a carriage return spring 8. It is always elastically biased towards the starting position). A type wheel group 10 consisting of four side-by-side type wheels 9a to 9d splined to the type shaft 3 is accommodated in the carriage 7. An end face cam 11 is fixed to the right end of the type wheel selection cam shaft 2, and as shown in Fig. 3A and B, one end face is divided into eight equal parts in the circumferential direction. Cam surface 12a, second cam surface 12b, third cam surface 12c, fourth cam surface 12d
are respectively provided, and the cam surfaces 12 are continuous with an inclined cam surface 13. Each cam surface 12 is vertical and has four stages at different positions, the stages corresponding to the number of type wheels 9 in the type ring group 10. As shown in FIGS. 1 and 2, a type wheel position sensor 18 is located at the left end of the type wheel selection camshaft 2, and a type wheel position sensor 18 is located at the right end of the type wheel selection camshaft 3.
A type position sensor 25 and a type reference position sensor 26 are each fixed.

As shown in FIG. 1, a hammer/carry cam holder 19 is slidably held on the print/carry shaft 4, and a hammer 16 and a carry cam 20 are arranged inside the hammer/carry cam holder 19. The carry cam 20 is splined to the print/carry shaft 4 and its type ring group 10
A hammer 16 is extrudably held on the side opposite to.

As shown in FIGS. 4, 5, and 6, the carry cam 20 has two protrusions 2 on its outer circumference at 180° intervals.
1 is formed. This protrusion 21 includes a circumferential protrusion 21a extending in the circumferential direction provided over approximately 1/4 of the circumferential direction of the carry cam 20, and a circumferential protrusion 21a provided over approximately 1/4 of the circumferential direction of the carry cam 20. The protrusion 21a and 21b are continuous. The protrusions 21 of the carry cam 20 are adapted to mesh with rack teeth 22 provided on the rack 5, as shown in FIG. The rack teeth 22 have a truncated conical shape as shown in FIGS. 7 and 8, and are arranged in rows at equal intervals along the longitudinal direction of the rack 5. As shown in FIGS.

As shown in FIG. 1, the carriage 7 is connected to a hammer/carry cam holder 19 by a rope (string body) 24 stretched through six rollers 23a to 23d. Therefore, during carrying, the carriage 7 is moved by the hammer/carrying cam holder 1.
9 and move by the same amount in the same direction. As mentioned above, the carriage 7 is always urged toward the home position by the carriage return spring 8, so that the protrusion 21 of the carry cam 20 normally meshes with the rack teeth 22 in an elastic manner. ing. Then, when the printing/carrying shaft 4 (carrying cam 20) is rotated 1/4 in the direction of arrow A as shown in FIG. , the carry cam 20 does not move and only rotates 1/4 turn on the spot.
When the printing/carrying shaft 4 (carrying cam 20) is then rotated 1/4 turn in the direction of arrow A, the next rack tooth 22 that was in contact with the circumferential protrusion 21a is moved. The spiral protrusion 21b of one protrusion 21 comes into sliding contact with the carry cam 2 as it rotates.
0 moves toward the side plate 1b by an amount equivalent to one digit, that is, in the direction of arrow B perpendicular to the feeding direction of paper 17 in FIGS. 1 and 6.

The hammer 16 is arranged together with a carry cam 20 in a holding body 19, while the carriage 7 is connected to the holding body 19 via a rope 24.
Therefore, the carry cam 20 is moved by the arrow B corresponding to one digit.
When moving in this direction, the carriage 7 and the hammer 16 are thereby also transported in the same direction and by the same amount.

As shown in FIG. 1, a roller 23a is disposed on the carry-up side of the carriage 7, that is, on the opposite side to the side to which the carriage return spring 8 is connected.
is rotatably supported by the free end of the rotary lever 14 for type wheel selection, and is movable in the carrying direction, whereas the other rollers 23b to
23c is in a fixed position. The base end of the rotary lever 14 for type wheel selection is pivotally supported by a printer board (not shown), and the tip is rounded at a position facing the end cam 11 between the base end and the free end. A sliding contact protrusion 15 is provided. As mentioned above, the carriage 7 is connected to the carriage return spring 8.
Since it is always pulled toward the home position by the roller 23a, it is connected to the carriage 7 and the roller 23a
The roller 23a is pulled in the direction of the carriage 7 by the rope 24 stretched between the rollers 23c and 23c. Therefore, the rotating lever 14 is biased toward the carriage 7, and the sliding protrusion 15 is always in elastic contact with the cam surface of the end cam 11.

The selection operation of the type wheel 9 is performed by the cooperation of the type wheel selection camshaft 2, end cam 11, rotary lever 14 for type wheel selection, sliding protrusion 15, type wheel position sensor 18, roller 23a, rope 24, etc. will be carried out.

That is, in the initial state, as shown in FIG.
6, and at this time, the sliding protrusion 15 is in contact with the lowest first cam surface 12a of the end cam 11 (see FIG. 3). As described above, the position where the first type ring 9a faces the hammer 16 is referred to as the reference position of the type ring group 10.

Next, when the type wheel selection camshaft 2 is rotated, the end face cam 11 is also rotated, so that the sliding protrusion 15 passes from the lowest first cam surface 12a to the adjacent inclined cam surface 13 to the second higher one. It contacts the cam surface 12b.
With this rotation of the end cam 11, the cam surface in contact with the sliding protrusion 15 changes from the first cam surface 12a to the second cam surface 12b.
By being displaced, the rotating lever 14 is pushed outward against the elasticity of the carriage return spring 8, and rotates about a predetermined angle about the base end as a fulcrum. As the rotary lever 14 rotates, the roller 23a also moves, so the carriage 7 is pulled via the rope 24, and as a result, the second type wheel 9b faces the hammer 16.

At this time, as the carriage 7 moves, the rope 24 connected to the side plate 1a side of the carriage 7 is pulled, and the tensile force is also applied to the hammer/carry-up cam holder 19; 2
0 is engaged with the rack 5, so when the type wheel 9 is selected, the hammer 16 and carry cam 20 do not move and remain fixed.

When the type wheel selection camshaft 2 is further rotated, the sliding contact protrusion 15 is moved to the third cam surface 12 which is even higher.
c, the rotary lever 14 and roller 23a rotate in the same manner as described above, and the third type ring 9c faces the fixed hammer 16. When the type wheel selection camshaft 2 is further rotated, the sliding contact protrusion 15 is moved to the third position.
As shown in FIG. 7B, the fourth type ring 9d contacts the highest fourth cam surface 12d, and accordingly faces the hammer 16. Next, when the type wheel selection camshaft 2 is rotated, that is, when it rotates once, the sliding protrusion 15 comes into contact with the first cam surface 12a again, and moves from the highest fourth cam surface 12d to the lowest first cam surface 12a. Due to the step and the restoring force of the carriage return spring 8 and the spring 101, the entire carriage 7 returns, and the first type ring 9a hits the hammer 16.
to face. Since the type wheel selection camshaft 2 rotates in only one direction, the feeding and return of the carriage 7 (type wheel group 10) are alternately repeated, and the shift selection of the type wheel 9 is performed during this period. The type wheel position sensor 18, which rotates integrally with the type wheel selection camshaft 2, detects which type wheel 9 is currently facing the hammer 16 and the position state of the type wheel 9.

As shown in FIG. 1, the torque of the motor 27, which always rotates in one direction, is applied to the type shaft 3 via the type selection clutch 28, and to the type wheel selection camshaft 2 via the type wheel selection clutch 29. The signals are also transmitted to the print/carry shaft 4 via the print/carry clutch 30, respectively. The rotation transmission between the type selection clutch 28 and the print/carry clutch 30 is switched by the first switching member 31, and the rotation transmission between the type wheel selection clutch 29 and the print/carry clutch 30 is switched. is appropriately performed by the second switching member 32. The first switching member 31 is operated by the first electromagnet 33, and the second switching member 32 is operated by the second electromagnet 3.
4 respectively.

For each clutch 28, 29, 30, the state in which rotation can be transmitted is ON, and the state in which rotation cannot be transmitted is OFF.
Then, when the first electromagnet 33 is not energized (de-energized state), the type selection clutch 28 is
ON, when the first electromagnet 33 is energized (excited state), the type selection clutch 28 is OFF.
Further, when the second electromagnet 34 is not energized (de-energized state), the type wheel selection clutch 29 is activated.
OFF, and when the second electromagnet 34 is energized (energized state), the type wheel selection clutch 29 is turned ON. Further, the first electromagnet 33 is energized and the second electromagnet 33 is energized.
The print/carry clutch 30 is ON only when the electromagnet 34 is not energized, and the print/carry clutch 30 is OFF under other conditions.

Next, the construction of each clutch and other parts related thereto will be explained with reference to FIG.

The type shaft 3 is connected to the type wheel group 10, the type selection clutch 28, and the rotational force from the type wheel selection clutch 29 to the type wheel position sensor 18 (type wheel selection camshaft 2).
A rotational force intermediate transmission body 35 for transmitting the rotational force to the rotational force intermediate transmission body 35 is respectively incorporated.

The type selection clutch 28 includes a drive side gear 37 having a cylindrical portion 36 protruding from the center of one side, a spring fixing ring 38, a type position selection ratchet 39, a coil spring 40, and a drive side gear 37 having a cylindrical portion 36 protruding from the center of one side. The cylindrical portion 36 is made up of a type side release cam 42 having a protruding annular portion 41 into which the cylindrical portion 36 is fitted.

One end 40a of the coil spring 40 is fitted into a locking groove 43a of the spring fixing ring 38, and the other end 40b is fitted and locked into a locking groove 43b provided in the annular portion 41 of the type side release cam 42, respectively. and,
With the coil spring 40 tightly wound around the cylindrical portion 36 of the drive side gear 37, the cylindrical portion 36 is inserted into the center hole of the spring fixing ring 38 and into the ratchet 39.
The drive side gear 37 loosely fitted to the type shaft 3 is inserted into the center hole of the annular part 41 of the release cam 42.
A spring clutch is formed between the release cam 42 and the release cam 42.

That is, the fan-shaped protrusion (see FIG. 2) provided on the annular portion of the release cam 42 engages with the fan-shaped notch provided on the side surface of the ratchet 39 (however, the fan-shaped protrusion and the notch do not rotate). The cylindrical portion of the spring fixing ring is tightly fitted into the center hole of the ratchet 39, and the three members 38, 39, and 42 rotate together as a driven side. This driven side is connected to a drive gear 37, which is the drive side of the clutch, via a coil spring 40. When the locking member is not fitted into the ratchet 39, the coil spring 40 is tightened and the driving side and the driven side rotate together, but as soon as the ratchet 39 is prevented from rotating, the coil spring 40 loosens. , the rotation on the driving side cannot be transmitted to the driven side.

The number of teeth of the type position selection ratchet 39 corresponds to the number of type portions 44 provided on the outer periphery of the type wheel 9. The type side release cam 42 is press-fitted into the type shaft 3 and rotates together with it.
A type side release groove 45 is formed at one location on the circumferential cam surface provided on the outer periphery. The printing part 44 on the outer periphery of the printing ring 9 is provided with only one so-called blank part without printing characters, and the area of the release groove 45 in the release cam 42 corresponds to the area of the blank part.

The rotational force intermediate transmission body 35 is loosely fitted to the type shaft 3,
A first intermediate transmission gear 47 that meshes with the driven gear 46 of the type wheel selection clutch 29, a second intermediate transmission gear 49 that meshes with the sensor gear 48 integrated with the type wheel position sensor 18, and It is composed of a type wheel shift side release cam 50 provided in between, and the three rotate as one. The number of teeth of the first intermediate transmission gear 47 is the same as that of the driven gear 46, and the number of teeth of the second intermediate transmission gear 49 is the same as that of the sensor gear 48. Therefore, when the driven side gear 46 of the type wheel selection clutch 29 rotates 1/4, the rotational force intermediate transmission body 35 also rotates 1/4, and the type wheel position sensor 18 similarly rotates 1/4, so that the driven side Gear 46 and type wheel position sensor 18
The directions of rotation are the same. A type wheel shift side release groove 51 is formed at one location on the circumferential cam surface provided on the outer periphery of the type wheel shift side release cam 50 .

A type wheel selection clutch (claw clutch) 29 incorporated in the print/carry shaft 4 includes a drive side gear 53 having a ratchet 52 protruding from the center of one side, and a rotatable engagement that engages with the ratchet 52. Stopper claw 54
, a type wheel selection control plate 55 , and a driven gear 46
The driving gear 53, the control plate 55, and the driven gear 46 are all rotatably held separately from the print/carry shaft 4. Notches 5 are provided at equal intervals on the circumferential cam surface of the type wheel selection control plate 55.
6 are formed, and the number of cutouts 56 is equal to the number of type wheels 9 to be mounted, that is, four in this embodiment. The type wheel selection clutch 29 is comprised of a so-called pawl clutch, in which a pin (not shown) protruding from the side surface of the driven gear 46 passes through a through hole in the control plate 55 and connects to a small hole that is the center of rotation of the locking pawl 54. When fitted and fixed, the pin at the tip of the locking claw 54 is connected to the control plate 5.
It is held in the through hole of 5 so that it does not fall out, and the 3 and 4
6, 54, and 55 are adapted to rotate together. Also, by a spring whose one end is locked to the pin of the locking pawl 54 and the other end is locked to the driven gear 46, the pawl portion of the locking pawl 54 is connected to the ratchet 52 that is integrated with the driving gear 53. There is a bullet contact. Therefore, when the locking member described later is not fitted into the notch 56 of the driven side control plate 55, the rotation of the driving side gear 53 is controlled by the driven side gear via the locking pawl 54 engaged with the ratchet 52. 46, and on the other hand, when the locking member fits into the notch 56 of the control plate 55 and the rotation is prevented, the locking pawl 54 that was engaged with the ratchet 52
resists the spring and separates from the ratchet 52, making it impossible to transmit rotation between the driving side and the driven side.

The print/carry clutch 30 built into the print/carry shaft 4 has a ratchet 57 at the center of one side.
a drive-side gear 58 protruding from the ratchet 5;
7, a print/carry control plate 60, and a control lever lock body 61. The drive side gear 58 and the print/carry control plate 60 are loosely fitted onto the print/carry shaft 4, and only the control lever lock body 61 rotates integrally with the print/carry shaft 4. That is, this print/carry clutch 30 is also a pawl clutch similar to the above-mentioned type wheel selection clutch 29, and the driven side, in which the three members 59, 60, and 61 are assembled so as to rotate together, The locking pawl 59 is connected to the drive gear 58 by a spring.
The on/off of the clutch is controlled depending on whether or not a locking member, which will be described later, fits into a notch 62 on the outer periphery of the control lever lock body 61.

On the circumferential cam surface of the print/carry control board 60,
Two notches 62 are provided at 180° intervals.
On the outer periphery of the control lever lock body 61, one raised tooth portion 63 is provided at an interval of 180°, and further, on the downstream side of the raised tooth portion 63 in the rotational direction, an arcuate lock portion is provided at a slight interval. 64 are formed respectively. The outer periphery of the lock portion 64 matches the tip circle of the raised tooth portion 63, and the outer peripheral portions other than the raised tooth portion 63 and the lock portion 64 are stepped down from these. It matches the root circle.

This control lever lock body 61 is adapted to engage with a carriage return/paper feed control lever 65 loosely fitted onto the paper feed shaft 6. The control lever 65 includes a lever body 66 that is rotatably supported by the paper feed shaft 6, a paper feed shaft drive ratchet 67 that is inserted into the hollow part of the lever body 66 and rotates integrally with the paper feed shaft 6, and a pawl. Piece 68 and biasing spring 69
and a support pin 70.

The lever main body 66 mainly consists of a first lever piece 66a and a second lever piece 66b that have substantially the same shape, and both lever pieces 66a and 66b are integrally molded with a predetermined interval in between. There is. Second
As shown in FIGS. 9, 10, and 11, a through hole 71 into which the paper feed shaft 6 is loosely fitted is formed at the center of rotation of both lever pieces 66a, 66b.

Control lever lock body 61 of first lever piece 66a
A fitting surface 72 of an arcuate recess having the same radius of curvature as the outer periphery of the lock portion 64 of the control lever lock body 61 is provided on the side surface facing the control lever lock body 61. As shown, the lock portion 64 is fitted into the fitting surface 72. Further, a sliding contact surface 74a is provided on the tip surface of the free end 73a of the first lever piece 66a, and is an arcuate recessed portion having the same radius of curvature as the outer periphery of the print side release cam 42, as shown in FIG. As the print side release cam 42 rotates, its outer cam surface and the sliding surface 74a come into sliding contact.

Moreover, the free end 73 of the second lever piece 66b
A sliding surface 74b is provided on the tip end surface of b, which is an arcuate concave portion having the same radius of curvature as the outer circumference of the type wheel shift side release cam 50, and as shown in FIG. As the roller 50 rotates, its outer cam surface and the sliding surface 74a come into sliding contact.

As shown in FIGS. 12 and 13, a tubular portion 76 having a wide-angle notch 75 is provided at the center of the outer surface of the second lever piece 66b. The engagement protrusion 78 of the release transmission body 77 is inserted. A pin 79 is protruded from the outer surface of the second lever piece 66b, and by elastically pressing the pin 79 downward with a spring, the carriage return/paper feed control lever 65 is moved clockwise in FIG. energized.

As shown in FIGS. 2, 9 to 13, insertion holes 80 into which the support pins 70 are inserted are formed on the free ends 73a and 73b of the first lever piece 66a and the second lever piece 66b, respectively. has been done. The claw piece 68 is rotatably supported by the support pin 70 inserted therein, the tip of the claw piece 68 engages with the teeth of the paper feed shaft driving ratchet 67, and the claw piece 68 is attached to the urging spring 69. Therefore, it is elastically biased in the direction in which it always engages with the ratchet 67.

The lock release transmitting body 77 is shown in FIGS. 2 and 1.
As shown in FIG. 4, it mainly consists of an annular part 81 and a gear part 82, the above-mentioned engagement protrusion 78 is provided on the side surface of the annular part 81, and a stopper 83 protrudes in a substantially tangential direction of the gear part 82. It is set up. This lock release transmission body 77 is loosely fitted to the paper feed shaft 6, and
By inserting the engaging protrusion 78 into the notch 75 of the lever 65, it is partially engaged with the carriage return/paper feed control lever 65 (see FIGS. 12 and 13).

The gear portion 82 of the rack release transmission body 77 meshes with an idler gear 84 shown in FIG.

As shown in FIG. 2, the first switching member 31 is composed of a pressing lever 86 and a claw member 87. The base of the pressing lever 86 is rotatably supported, and its free end is in elastic contact with the circumferential cam surface of the print/carry control plate 60 by a spring means (not shown). An engagement groove 88 is formed at the free end of the pressing lever 86, into which a connecting pin 89 of the claw member 87 is inserted. The claw piece member 87 is pivotably supported at its intermediate portion, has the connecting pin 89 formed at one end, and has the character position selection ratchet 39 formed at the other end.
A locking pawl 90 is provided that meshes with the teeth of the holder.

The second switching member 32 is pivotably supported at its intermediate portion, and has a locking pawl 91 that engages with the notch 62 of the print/carry control board 60 at one end, and a type wheel selection control at the other end. A locking pawl 92 that engages with the notch 56 of the plate 55 is provided, respectively.

As shown in FIG. 1, a rack return member 93 spline-coupled to the print/carry shaft 4 is held near the inner surface of the side plate 1a of the print/carry shaft 4. As shown in FIGS. 2 and 15, two push teeth 94 are provided on the outer periphery of the rack 5 at an interval of 180°, and on the outer periphery of the end of the rack 5 there is a single push tooth 94 that can be engaged with the push teeth 94. Two receiving teeth 95 are provided protrudingly. As shown in FIG. 2, only when the hammer 16 and the carry cam 20 return to their home positions are they pressed in the upper right direction in FIG. The pushing tooth 94 is pressed in the direction of the receiving tooth 9 of the rack 5.
It is now facing 5.

Next, the operating order of this printing device will be explained. Note that FIGS. 16A, 16B, and 16C are diagrams for explaining the operating states of each clutch, and FIG. 17 is a timing chart of each output signal and each operation.

When printing for one line is started, as shown in FIG. 1, the carriage 7 is on standby at the home position by the carriage return spring 8, and the type wheel group 10 is on standby at the reference position. In this standby state, the motor 27 starts rotating based on a one-line printing command from a control section (not shown) (time T ₁ in FIG. 17). In the initial state, neither the first electromagnet 33 nor the second electromagnet 34 is energized, so the first switching member 31 engages with the print/carry control board 60 as shown in FIG. The switching member 32 is engaged with the type wheel selection control plate 55, and the type position selection ratchet 39 is engaged with the first switching member 31.
and is in a disengaged state. Therefore, the type wheel selection clutch 29 and the print/carry clutch 30 are OFF.
The type selection clutch 28 is in the ON state,
The power of the motor 27 is transmitted only to the type shaft 3, and only that is rotating. As the type shaft 3 rotates, an ink roller (not shown) mounted on the carriage 7 applies ink to the outer periphery of each type wheel 9a to 9d.

Note that before the motor 27 rotates, the rack 5 is rotated slightly clockwise as shown in FIG. Since the rack 5 and the carry cam 20 are separated, the rack 5 and the carry cam 20 are in a non-engaging state, and the receiving tooth 95 faces the rack return member 93.

When the type shaft 3 rotates as described above, the type position sensor 25 outputs a type position detection signal as shown in FIG. 17, and the type reference position sensor 26 outputs a type reference position signal. When the type shaft 3 continues to rotate, a type reference position signal is output periodically, and 15 pulses of the type position detection signal are output before the next type reference position signal is output, and this number is equal to the number of type wheel 9. This corresponds to the number of printed characters (including blank parts), and in this embodiment, the printed character position detection signal is output about 15 times.

When the first character position detection signal is output at time _T2 in FIG. 17, the second electromagnet 34 is excited based on the signal, and the second switching member 32 rotates against the elasticity of the biasing spring. With this rotation, the engagement between the second switching member 32 and the type wheel selection control plate 55 is released, as shown in FIG.
turns on. As a result, the rotational driving force of the motor 27 is transmitted to the driving side gear 53, the type wheel selection control plate 55, the driven side gear 46, and the rotational force intermediate transmission body 35 meshing with the driven side gear 46, as shown in FIG. ,
The rotational force is sequentially transmitted to the type wheel position sensor 18 that is engaged with the intermediate transmission body 35, and the type wheel selection camshaft 2 that is engaged with the type wheel position sensor 18.
They are rotated. Based on the rotation of the type wheel selection camshaft 2, a type wheel reference position detection signal is generated from a type wheel reference position sensor (not shown) and a type wheel position sensor 18, which rotate integrally with the type wheel selection camshaft 2, as shown in FIG. A wheel position detection signal is output.

Also, together with the type wheel selection camshaft 2, the end face cam 1
1 also rotates, whereby the carriage 7 (type wheel group 10) is gradually shifted in the direction of arrow B as described above (see FIG. 1), and the type wheel 9 facing the hammer 16 is sequentially changed.

The rotation of the type wheel selection camshaft 2 and type shaft 3 selects the type wheel 9 that holds the desired type to be printed, and selects the desired type or another type wheel 9 that is on the same generatrix as the desired type. Type selection is made. The order of the shift selection of the type wheel 9 (selection of the sliding position in the direction of arrow B) and the selection of the type, that is, the selection of the rotation stop position of the type wheel group 10, is arbitrary.
The shift selection and the rotation stop position selection are performed one after the other, although they differ depending on the position of the type to be selected or the transmission ratio from the motor 27 to the type wheel selection camshaft 2 and type shaft 3.

In FIG. 17, for example, at time T ₃ , the type wheel 9
When the shift selection is made, the second electromagnet drive signal is activated at the rising edge of the type wheel position detection signal.
Turn off. As a result, the second electromagnet 34 is de-energized, the second switching member 32 returns to its original state due to the restoring force of the biasing spring, and the type wheel selection control plate 55
On the other hand, it is separated from the print/carry control board 60 and is in a non-engaging state. Therefore, at this time _T3 , the type wheel selection clutch 29 is turned OFF and the rotation of the type wheel selection camshaft 2 is stopped, but the rotation of the type wheel selection camshaft 3 is continued. Note that the type wheel position detection signal that rose at time _T3 is the third signal from the previously outputted type wheel reference position detection signal, so the third type wheel 9c (see Fig. 1) )
The transfer in the direction of arrow B is stopped at a position where the letter wheel group 10 faces the hammer 16, and the type wheel group 10 is rotating at that position.

Thereafter, when the type is selected at time _T4 , that is, the rotation stop position of the type wheel group 10 is selected, the first electromagnet drive signal is output at the rising edge of the type position detection signal, and based on that signal, the first electromagnet 3
3 is excited. As a result, the first switching member 31 rotates against the elasticity of the biasing spring, moves away from the print/carry control plate 60, and becomes disengaged. Ratchet 39
engage with.

Therefore, at this time _T4 , as shown in FIG. 16C, the type position selection ratchet 39 (type selection clutch 28) and type wheel selection control board 55 (type wheel selection clutch 29) are OFF, and the print/carry control is turned off. The plate 60 (print/carry clutch 30) is in the ON state, and the type wheel group 10 is stopped with the desired type facing the hammer 16. The type position detection signal that rises at time _T4 is the seventh signal from the previously outputted type reference position detection signal, so it is the seventh signal from the type reference position predetermined on the type wheel 9. This means that the th printing section faces the hammer 16. The first turned on at time T ₄
Since the electromagnet drive signal is turned OFF at the rising edge of the next character position detection signal (time T ₅ ), the excitation of the first electromagnet 33 is instantaneous, and during this period, the printing/carry control board 60 and the first switching The engagement with the member 31 is released, and then the printing/carrying operation begins.

When the first switching member 31 separates from the notch 56 of the print/carry control board 60, the print/carry control board 60
0, the control lever lock body 61, the print/carry shaft 4 engaged with the control lever lock body 61, the rack return member 93 spline-coupled to the print/carry shaft 4, and the carry cam 20 rotate. . When the first electromagnet 33 is de-energized after its rotation starts, one end of the first switching member 31 comes into elastic contact with the circumferential cam surface of the print/carry control board 60 due to the restoring force of the biasing spring. Print/carry control board 60
1 until the print/carry shaft 4, etc. rotates half a turn.
Their rotation is not prevented by the switching member 31.

At the initial stage of rotation of the rack return member 9, as shown in FIG.
Push the receiving tooth 95 of the rack 5 in the direction of arrow C. As a result, the rack teeth 22 that have fallen down until now are returned to the position facing the carry cam 20, and the rack teeth 22 mesh with the protrusions 21 of the carry cam 20. As a result, the shift canceling operation is completed as shown in FIG. 17, and a shift becomes possible.

In addition, the carry cam 20 also rotates synchronously, but as mentioned above, the first 1/4 rotation is performed by the circumferential protrusion 2
Since 1a is in sliding contact with the rack teeth 22, the carry cam 20 does not move and rotates on the spot. As shown in FIGS. 2, 4, and 5, two hammer push-out protrusions 96 are provided on both end surfaces of the carry cam 20 at an interval of 180 degrees. Therefore, during the first quarter rotation of the carry cam 20, the hammer 16 is pushed out by the hammer pushing protrusion 96 toward the type wheel 9 against the elasticity of the hammer return spring (not shown), and the paper 17 is pressed against the type portion facing the hammer 16 to print.

With the subsequent 1/4 rotation of the carry cam 20, the hammer pushing protrusion 96 separates from the hammer 16, and the hammer 1
6 returns to its original position by the restoring force of the hammer return spring.
At the same time, the helical protrusion 21b of the carry cam 20 comes into sliding contact with the rack teeth 22, and the carry cam 20
As the hammer/carry cam holder 1 rotates,
9 is moved in the direction of arrow B in FIG. 1 by a distance corresponding to one digit. As the hammer/carry cam holder 19 moves, the hammer 16, carriage 7, type wheel group 10, etc. are also moved in the direction of arrow B by an amount equivalent to one digit, in preparation for the next printing.

As mentioned above, the control lever lock body 61 also rotates half a turn during the printing/carrying operation, but as shown in FIGS.
As shown in FIG. 2, the sliding surface 7 of the first lever piece 66a
4a comes into contact with the circumferential cam surface of the stopped print side release cam 42, and the sliding contact surface 74 of the second lever piece 66b
b is in contact with the circumferential cam surface of the stopped type wheel shift side release cam 50, so even if the lock portion 64 of the control lever lock body 61 comes off the fitting surface 72 of the first lever piece 66a, the printer will not be able to move. Tsuji return・
The paper feed control lever 65 is held at that position without rotating.

As described above, when the print/carry control board 60, control lever lock 61, print/carry shaft 4, etc. rotate half a turn, one end of the first switching member 31 falls into the notch 62 of the print/carry control board 60. At the same time, the other end of the first switching member 31 is separated from the type position selection ratchet 39,
Return to the state shown in Fig. 16A. And only the type selection clutch 28 (type position selection ratchet 39)
The second electromagnet drive signal is turned ON and the second electromagnet drive signal is output at the first rise of the type position detection signal (time T ₆ in FIG. 17). In this way, by sequentially repeating the shift selection of the type wheel 9, selection of the rotation stop position, printing, and carrying, one digit is printed.

Next, the carriage return and paper feeding operations will be explained. When carrying out a carriage return/paper feed operation, the release groove 45 of the type side release cam 42 is moved to the first lever piece 6 by an operation command from the control section.
Shift selection and rotation stop position selection of the type wheel 9 are performed so that the sliding surface 74a of the type wheel 9a and the release groove 51 of the type wheel shift side release cam 50 respectively face the sliding surface 74b of the second lever piece 66b. will be carried out. Since the release groove 45 faces the sliding surface 74a and the release groove 51 faces the sliding surface 74b in this way,
The engagement between the rotational force intermediate transmission body 35 and the carriage return/paper feed control lever 65 is released. However, at this point, the control lever lock body 61 is stopped with its lock portion 64 fitted into the fitting surface 72 of the first lever piece 66a, so the carriage return/paper feed control lever 65 is not controlled. It is locked by a lever lock body 61 to prevent rotation.

Thereafter, when the control lever lock body 61 rotates based on the print/carry signal, the lock portion 64 locks onto the fitting surface 7 of the first lever piece 66a, as shown in FIG.
2, and the stepped outer peripheral part of the control lever lock body 61 faces the first lever piece 66a.
The carriage return/paper feed control lever 65, which has lost its mooring means, is rotated in the direction of arrow D by the pressure of the biasing spring. At this time, as shown in FIGS. 12 and 13, the tubular portion 76 of the second lever piece 66b
Since the engagement protrusion 78 of the lock release transmitting body 77 is in contact with the lever, the lock release transmitting body 77 is pushed together with the carriage return/paper feed control lever 65 and rotates together. Then, the stopper 83 of the lock release transmitting body 77 is moved to an appropriate stopper piece 97.
13), the carriage return/paper feed control lever 65 and the lock release transmitting body 77 stop rotating.

With this rotation of the lock release transmission body 77,
The idler gear 84, rack release gear 85, and rack shown in FIG. 2 rotate, thereby releasing the engagement between the rack teeth 22 and the protrusion 21 of the carry cam 20 (as of T ₇ in FIG. 17). ). When the engagement between the rack 5 and the carry cam 20 is released, the tension of the carriage return spring 8 causes the carriage 7, type ring group 10, hammer 16, hammer/carry cam holder 19, carry cam 20 etc. will return to the home position. Even when these return to their home positions, the rack 5 remains in a rotating state. Also, as the hammer/carry cam holder 19 returns, the rack return member 9 is removed as described above.
3 slides so that its pushing tooth 94 faces the receiving tooth 95 of the rack 5.

As shown in FIG. 10, when the carriage return/paper feed control lever 65 rotates in the direction of arrow D around the paper feed shaft 6, the paper feed shaft drive ratchet 67 is supported by the paper feed shaft 6. Because it is there, it does not rotate and remains in the same state. As the carriage return/paper feed control lever 65 rotates, the tip of the claw piece 68 supported by it moves.
It crosses over the ratchet tooth one rear of the ratchet tooth of the ratchet 67 that has been engaged so far and engages with it.

Then, based on the subsequent printing/carrying operations, the 11th
As shown in the figure, when the control lever lock body 61 rotates, its raised teeth 63 lock onto the control lever 65.
It fits into a groove 98 provided next to the fitting surface 72 of. When the control lever lock body 61 continues to rotate, the control lever 65 is rotated in the direction of arrow E by the raised tooth portion 63 and returns to its original state, and the lock portion 64 of the control lever lock body 61 engages with the control lever 65. Upon contact with the mating surface 72, the control lever 65 is locked again.

As described above, when the control lever 65 rotates in the direction of the arrow E, the paper feed shaft driving ratchet 67 is rotated by the claw piece 68 supported thereon. The paper feed shaft 6 is press-fitted and fixed into the ratchet 67, and the paper feed shaft 6 is connected to a paper feed roller 99 made of a rubber roller as shown in FIG. The rotation causes the paper feed roller 99 to rotate, and the paper 17 is fed by a predetermined amount.

Carriage return and paper feeding operations are performed in this manner, but the rack 5 remains disengaged from the carry cam 20. Further, as shown in FIGS. 12 and 13, the notch 75 of the tubular portion 76 of the second lever piece 66b is formed with an enlarged angle, and the engaging protrusion of the narrow release transmission body 77 is formed in the notch 75 of the tubular portion 76 of the second lever piece 66b. 78 is loosely fitted, even if the carriage return/paper feed control lever 65 is rotated in the direction of arrow E to return to its original position, the lock release transmission body 77 will not return and will remain as it is. It's on.

These racks 5 and the rack release transmitter 77
The return of is performed at the first printing on the next line. That is, as mentioned above, the rotation of the rack return member 9 at the beginning of the printing/carrying operation causes the rack 5 to be
is returned to a position facing the carry cam 20.
Further, by the rotation of the rack 5, the rack release transmission body 77 is returned to its original state via the rack release gear 85 and the idler gear 84, so that it can be engaged with the tubular body 76 of the second lever piece 66b.

At the time of carriage return, the rack 5 is rotated to disengage from the carry cam 20, thereby carrying out the carriage return, and the rack 5 remains rotated even after the carriage return is completed. The rack 5 is then returned to its original position and engaged with the carry cam 20 at the first print/carry operation of the next line.

In order to further improve the degree of alignment of the print lines printed on the paper 17, the design is such that the play in the shafts 2, 3, 4 of the carriage 7, type ring group 10, carry cam 20, etc. is minimized. Therefore, for example, when the printing device is used at low temperatures, the carriage 7, type ring group 10, carry cam 20, etc. do not return easily, and the carriage return operation takes time. If the rack 5 is returned to its original position before the carriage return is completed, the carry cam 20 will get caught in the middle of the rack 5, and the printing position on the paper 17 will be different.

With the configuration of this embodiment, there is enough time for the carriage return to start and for the rack 5 to return to its original position, and for the carriage 7, carry cam 20, etc. to be completely at home. After returning to the position, the rack 5 can be rotated and engaged with the carry cam 20, thereby eliminating the above-mentioned inconvenience.

In the embodiment described above, the end cam 11, the rotary lever 14 for selecting a type wheel, the roller 23a, etc. were used as the means for pulling the rope 24 for selecting the type wheel 9. However, the present invention is not limited thereto. It is also possible to configure the roller 23a to act as a winding roller for the rope 24 only when selecting the type wheel, and to select the type wheel 9 by winding the rope 24. In this case, when carrying, the roller 23a
The rollers 23b to 23c rotate in synchronization with the other rollers 23b to 23c. Alternatively, a movable clamping means may be used that grips the rope 24 and selects the type wheel 9 while pulling the rope 24 in a predetermined direction only when selecting the type wheel.

As described above, the printing device according to the present invention has a plurality of type carriers arranged side by side, a type carrier group movable in a direction interlinking with the feeding direction of paper, and a type carrier group facing the type carrier group via the paper. a hammer means capable of pressing the paper against a type portion held by a type carrier to print a desired character on the paper and transporting the type carrier group in the same direction as the type carrier group; the hammer means and the type carrier group; a connecting strip that connects and transfers the hammer means; a fixing means that fixes the hammer means at a predetermined position; and a fixing means that fixes the hammer means at a predetermined position, and The apparatus is characterized by comprising type carrier selection means for moving the type carrier group to face the hammer means by pulling the connecting strip between the type carrier group and the type carrier group. .

Therefore, the hammer means can print on a desired type carrier among the plurality of type carriers in the group of transportable type carriers, so the structure is simplified, the size and weight can be reduced, and a large number of symbols can be printed. It is possible to provide a printing device capable of printing symbols such as alphanumeric characters.

[Brief explanation of drawings]

The drawings all show a printing device according to an embodiment of the present invention; FIG. 1 is a schematic configuration diagram of the printing device, FIG. 2 is an exploded perspective view of each clutch means and its vicinity,
Figures 3A and 3B are a front view of the end cam and a developed view of the cam surface, Figures 4, 5, and 6 are a plan view, front view, and developed view of the cam surface of the carry cam, and Figures 7 and 8 is a plan view and a side view of the rack; FIGS. 9, 10, and 11 are explanatory diagrams showing the operating states of the control lever lock body, the first lever lock body, the first lever piece, and the type side release cam; FIGS. 12 and 13 are explanatory diagrams showing the operating states of the second lever piece and the type wheel shift side release cam, FIG. 14 is a perspective view of the rack release transmission body, and FIG. 15 is an illustration showing the operating states of the rack return member. FIG. 16 is an explanatory diagram showing the operating states of each clutch, and FIG. 17 is a timing chart of each output signal and each operation. 7... Carriage, 8... Carriage return spring, 9, 9a to 9d... Type ring, 10... Type ring group, 11... End cam, 12, 12a to 12d
... Cam surface, 13 ... Inclined cam surface, 14 ... Rotating lever for type wheel selection, 15 ... Sliding protrusion, 16 ...
... Hammer, 17 ... Paper, 23a ... Roller, 2
4...rope.

Claims (1)

[Claims] 1. A group of type carriers in which a plurality of type carriers are arranged side by side and can be transported in a direction interlinking with the feeding direction of paper, and a type carrier that faces the group of type carriers via the paper and holds the paper. a hammer means that presses against the type part to print desired characters on the sheet of paper and can be transported in the same direction as the type carrier group; and a connecting line that connects and transports the hammer means and the type carrier group. a fixing means for fixing said hammer means in a predetermined position; said fixing means fixing said hammer means in a predetermined position and said connecting strip between said hammer means and a group of type carriers; 1. A printing device comprising type carrier selection means for moving the group of type carriers by pulling and causing a desired type carrier to face the hammer means.