JPH042108B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a printer, and more particularly to a printer having an improved type selection mechanism that locks rotation of a type wheel.

[Background of the invention]

Conventionally, a plurality of type wheels having type bodies on the circumference are attached in rows, for example, 18 rows, to a rotating shaft arranged parallel to a platen around which recording paper is wound, and the rotation of each type wheel is individually controlled. Accordingly, printers that can perform desired printing have been proposed. In this printer, a selection ratchet is formed in the body of each type wheel, each of these selection latches is provided with a lockable locking pawl, and each of these locking pawls engages with the selection ratchet. A drive source, such as a solenoid, is provided for driving the locking pawl so that the locking pawl and the selection ratchet are disengaged from each other.

That is, in this conventional printer, 1
One solenoid is required to lock the rotation of two type wheels, which requires a large number of parts and assembly man-hours.
Therefore, it requires a considerably large space for arranging the parts, increases the manufacturing cost, and has the disadvantage of being subject to restrictions on the design of the arrangement of the parts.

[Purpose of the invention]

The present invention has been made in view of the actual state of the prior art, and its purpose is to provide a printer that can reduce the number of drive sources provided for stopping the rotation of the type wheel. It is in.

[Summary of the invention]

In order to achieve this object, the present invention includes a rotating shaft, a first type wheel mounted on the rotating shaft and having a first type body on the circumferential side, and a first type wheel that rotates together with the first type wheel and has a first type body on the circumferential side. a first selection ratchet having a first tooth portion formed at a position corresponding to the first type body on the side; a first selection ratchet attached to the rotating shaft and connected to the first type ring; a second type wheel having two type bodies; and a second selection having a second tooth portion which rotates together with the second type wheel and is formed on the circumferential side at a position corresponding to the second type body. A ratchet, a rigid first arm that has a protrusion that can be engaged with the notch of the rotating shaft, and a second elastic arm that is integrally provided with the first arm. a driving pawl and a spring member capable of holding the locking pawl in engagement with and disengaged from the selection ratchet, the approach of the second arm of the driving pawl to the bearing of the type wheel; A protrusion is provided on the outer periphery of the bearing as a regulating part for regulating the type wheel. The shaft is supported by the engaging portion of the drive pawl hole, and the phase of the first tooth portion and the second tooth portion are supported.
arranging the first type wheel, the first selection ratchet, the second type wheel, and the second selection ratchet so that the phases of the tooth portions are different from each other, and rotating each of the drive pawls of each selection ratchet. a guide portion is provided for the rotational shaft, the notch portion 12 of the rotational shaft has a first surface extending toward the axial direction of the rotational shaft, and the protrusion of the first arm of the drive claw and a second surface that can be adapted to the surface of the projection, and when selecting type, the first surface of the notch presses the second surface of the protrusion as the rotation shaft rotates. It is configured.

[Embodiments of the invention]

Hereinafter, the printer of the present invention will be explained based on the drawings. FIG. 1 is an exploded perspective view showing the main parts of an embodiment of the printer of the present invention, and FIGS. 2a and 2b show the engagement relationship between the rotating shaft and the drive pawl provided in the embodiment shown in FIG. 1. The construction drawings and FIGS. 3a, 3b, and 3c are explanatory diagrams showing the engagement relationship between the selection ratchet, the locking pawl, and the spring member provided in the embodiment shown in FIG. 1.

In FIG. 1, reference numeral 11 denotes a rotating shaft, which is provided with a V-shaped notch 12 on the circumferential side along the axial direction, and this rotating shaft 11 is arranged parallel to a platen around which recording paper (not shown) is wound. be done. Note that the notch 12
As shown in FIG. 2b, the rotary shaft 11 has a first surface 12a extending toward the axis O of the rotating shaft 11. 1
Reference numerals 3 and 14 denote a first type ring and a second type ring attached to this rotary shaft 11, which are located on the circumferential side 15 and 16, respectively.
A bearing 1 is provided with a plurality of first typefaces and a plurality of second typefaces, and a rotating shaft 11 is inserted in the center of the bearing 1.
7,18. Cavities 19 and 20 are formed in some of the bearings 17 and 18, and the bearings 17 and
Projections 21 and 22 are provided on the outer periphery of the bearing 18, and shafts 23 and 24 are provided at the portions of the type wheels 13 and 14 near the bearings 17 and 18, respectively.

Further, 25 and 26 are provided separately from the type wheels 13 and 14, for example, and include a first selection ratchet and a first selection ratchet that are fitted onto these type wheels 13 and 14 and rotate integrally with the type wheels 13 and 14. 2 selection ratchets, bearings 1 for type wheels 13 and 14 in the center, respectively.
It has holes 27 and 28 into which letters 7 and 18 are inserted, and a first tooth part 29 and a second tooth part 30 on the circumferential side and at positions corresponding to the type bodies of the type wheels 13 and 14. There is.

Further, 31 and 32 are drive claws disposed between the type wheel 13 and the selection ratchet 25 and between the type wheel 14 and the selection ratchet 26, respectively, and transmitting the rotational force of the rotary shaft 11 to the type wheels 13 and 14, respectively. It has holes 33, 34 which are inserted into the shafts 23, 24 provided in the type wheels 13, 14 so as to be relatively rotatable therein, and projections 35, 36 which can be engaged with the notch part 12 of the rotary shaft 11. and has rigidity.
arms 37, 38, and a second elastic arm 39,
It consists of 40. Moreover, the protrusions 35 and 36 are
Notch 1 of the rotating shaft 11 shown in FIG. 2b mentioned above
a second surface 41 that is compatible with the first surface 12a of 2;
42 each.

Note that the selection ratchets 25 and 26 described above are connected to the type wheels 13 and 14, as illustrated in FIGS. 2a and 2b.
recesses 43 and 44 into which the drive claws 31 and 32 can be inserted, and first arms 3 of the drive claws 31 and 32
The parts where the tips 45 and 46 of 7 and 38 movably engage, that is, the drive claws 31 and 32, are connected to the shafts 23 and 24.
Guide portions 47 and 48 are provided for rotation around the center. Further, the projections 21 and 22 of the bearings 17 and 18 described above are connected to the second arms 3 of the drive claws 31 and 32.
9 and 40 from approaching the bearings 17 and 18.

The above-mentioned type wheels 13, 14, drive claws 31, 3
2. The selection latches 25 and 26 are attached to the rotating shaft 11 in the following manner. That is, for example, the bearing 17 portion of the first type ring 13 is inserted into the rotating shaft 11, then the hole 33 of the drive pawl 31 is inserted into the shaft 23 of the first type ring 13, and the protrusion 3 of the first arm 37 is inserted into the shaft 23 of the first type ring 13.
5 is inserted into the cavity 19 of the bearing 17, and then, for example, the protrusion 35 is engaged with the notch 12 of the rotating shaft 11. Further, the second arm 39 is mounted so as to engage with the protrusion 21 of the bearing 17. Then the first
The hole 27 of the selection ratchet 25 is inserted into the rotating shaft 11, and the first selection ratchet 25 is connected to a first type body whose first teeth 29 are provided on the circumferential side of the first type wheel 13. It is fitted into the first type ring 13 so as to correspond to the position .

Similarly, the bearing 18 portion of the second type wheel 14 is inserted into the rotating shaft 11, then the hole 34 of the drive pawl 32 is inserted into the shaft 24 of the second type wheel 14, and the protrusion of the first arm 38 is inserted into the shaft 24 of the second type wheel 14. 36 is inserted into the cavity 20 of the bearing 18, and then, for example, this protrusion 36 is inserted into the rotating shaft 1.
It is engaged with the notch part 12 of 1. Further, the second arm 40 is mounted so as to engage with the protrusion 22 of the bearing 18 . The second selection ratchet 26 then
The second tooth portions 30 are fitted into the second type ring 14 such that the positions of the second teeth 30 correspond to the positions of the second type bodies provided on the circumferential side of the second type ring 14. .

The above-described first type wheel 13, first selection ratchet 25, second type wheel 14, and second selection ratchet 26 are connected to the phase of the first toothed portion 29 and the phase of the second toothed portion 30. They are arranged on the rotating shaft 11 such that they are different from each other, for example, shifted by 1/2 pitch from each other, that is, the second teeth 30 are located at positions corresponding to the spaces between the first teeth 29.

Further, reference numerals 49 and 50 shown in FIG.
The hole 5 has claws 51 and 52 at its tips that engage the teeth 29 and 30 of the hole 5, and a rotating shaft 53 is inserted into the center.
It has 4,55.

Reference numeral 56 denotes a driving source, such as an electromagnetic coil, which has a hole 57 in the center into which the rotation shaft 53 is rotatably inserted. Reference numeral 58 denotes a holding stand for holding the electromagnetic coil 56, and the electromagnetic coil 56 is held in a fan-shaped protrusion 59 formed on the upper part of the holding stand 58. Although not shown, there is a slightly larger fan-shaped notch at the bottom of the first locking claw 49, which corresponds to the shape of the protrusion of the holding base of the adjacent electromagnetic coil. A slightly larger fan-shaped notch 60 corresponding to the shape of the protrusion 59 of the holding base 58 is formed at the lower part of the locking pawl 50 . A yoke 61 is attached to surround the electromagnetic coil 56, and has a notch 62 on one side. Reference numeral 63 denotes a rotating body made of a non-magnetic material, which has a hole 64 in the center into which the rotating shaft 53 is inserted, and a protrusion 65 on the circumferential side that engages with the notch 62 of the yoke 61.
have. This rotating body 63 rotates together with the rotating shaft 53. The above electromagnetic coil 56, yoke 6
1. The rotating body 63 has a first locking claw 49 and a second locking claw 49.
It constitutes a driving means for rotating the locking pawl 50, that is, an electromagnetic clutch.

Further, reference numerals 66 and 67 are spring members capable of holding the locking pawls 49 and 50 in a state in which they are engaged with the selection latches 25 and 26 and in a state in which they are separated from the selection latches 25 and 26. It is provided with bent portions 76 and 77 consisting of upper portions 72 and 73 and lower portions 74 and 75 that are engageable with lower portions 68 and 69 and upper portions 70 and 71 of the distal end, respectively.

When assembling these locking claws 49, 50, electromagnetic coil 56, etc., they are attached to the electromagnetic coil 56 as described above, and the protrusion 6 of the rotating body 63
5 is arranged so as to fit into the notch 62 of the yoke 61, and the locking claws 49 and 50 are rotatable about the rotation shaft 53. In order to fit the protrusion 59 of the
The locking claw 49 is similarly attached to the adjacent electromagnetic coil, and the rotating body 63 is provided integrally with the rotating shaft 53 as described above. In this assembled state, the bodies 78, 79 of the locking claws 49, 50 are arranged to face the side end surfaces 80, 81 of the yoke 61, respectively.

Although not shown, the two type wheels 13, 14, selection ratchets 25, 26,
Drive claws 31, 32 and two locking claws 49, 5
0, spring members 66, 67, one electromagnetic coil 5
6. A plurality of combinations, for example nine sets, of the holding base 58, the yoke 61, and the rotating body 63 are arranged along the respective axial directions of the rotating shaft 11 and the rotating shaft 53.

The operation of the embodiment configured as described above is as follows.

That is, as shown in FIG. 3a, the locking claw 4
The lower portions 7 of the bent portions 76, 77 of the spring members 66, 67
4 and 75 are engaged, and in addition, as shown in FIG. For example, the rotating shaft 11 is rotated by a motor (not shown) in the direction of arrow 82 in FIG. 2a, that is, in the direction of arrow 83 in FIG.
3 rotates in the direction of the arrow 84 in FIG. A rotational force is transmitted to the drive claws 31, 32 by pressing the surfaces 41, 42 of the drive claws 31, 32, and this rotational force is transmitted from the tips 45, 46 of the first arms 37, 38 of the drive claws 31, 32 to the selective ratchets. The driving force is transmitted to the guide portions 47, 48 of the drive claws 31, 32, thereby driving the selection latches 25, 26.
The type wheels 13 and 14 rotate integrally with the rotary shaft 11 in the direction of the arrow 82.
During this time, the rotating body 6 rotates as the rotating shaft 53 rotates.
3 and the yoke 61 rotate, but the locking claw 4
Since the rotational force of the rotation shaft 63 is not transmitted to the locking claws 49 and 50, these locking claws 49 and 50 are
It is kept in the standby state shown in Figure a.

For example, when a desired type body on the first type wheel 13 comes close to a printing position corresponding to a platen (not shown), the electromagnetic coil 56 is energized, thereby causing the body portions 78 of the locking pawls 49, 50 to , 79 are attracted to the side end surfaces 80, 81 of the yoke 61. Therefore, the locking claws 49 and 50 try to rotate integrally with the yoke 61 as shown by arrows 85 in FIGS. 3b and 3c, but at this time, the first locking claw 49 The claw portion 51 is connected to the first selection ratchet 25.
As shown in FIG. 3B, the distal end of the locking pawl 49 climbs over the bent portion 76 of the spring member 66 and rotates in the direction of the arrow 85, and the pawl 51 and the first toothing 29 engage, thereby locking the rotation of the first selection ratchet 25, that is, the rotation of the first type wheel 13. On the other hand, as shown in FIG.
and is kept in this state. The second selection ratchet 26 and second type wheel 14 therefore continue to rotate. Further, for example, the electromagnetic coil 56 is de-energized in synchronization with the rotation locking of the first type wheel 13, and therefore, the rotational force of the rotation shaft 53 is not transmitted to the second locking pawl 50. When the second locking pawl 50 is cut off, the force of the spring member 66 causes the second locking pawl 50 to move to the third locking pawl 50.
It returns to the standby state shown in Figure a. Therefore, regardless of the rotation of the rotation shaft 53, this second locking pawl 5
0 and second selection ratchet 26 do not engage.

Note that when the rotation of the first selection ratchet 25 is locked by the first locking pawl 49 as described above, as the rotation shaft 11 continues to rotate in the direction of the arrow 82 in FIG. Then, the first drive claw 31
The tip 45 of the arm 37 is the first selection ratchet 25.
The drive pawl 31 is guided by the guide portion 47 provided in the second arm 39 and moves outward as shown by the arrow 86 in FIG. Therefore, the engagement between the protrusion 35 of the first arm 37 and the notch 12 of the rotary shaft 11 is released, and the rotational force of the rotary shaft 11 is transmitted to the first selection ratchet 25 and the first type ring 13. is cut off.

In this way, the first type wheel 13 is positioned at the printing position of the desired type. At this time, the first locking pawl 49 is moved to the first position of the first selection ratchet 25 by the spring force of the spring member 66.
It is stably held in an engaged state in which it engages with the tooth portion 29 of.

Then, the second type wheel 14 is positioned at the printing position of the desired type body in substantially the same manner as described above. That is, when the desired type on the second type wheel 14 comes close to the printing position facing the platen (not shown), the electromagnetic coil 56 is energized, thereby causing the second locking pawl 50 to move as shown in FIG. As shown by the arrow 85 in b, the spring member 67 passes over the bent portion 77 and rotates integrally with the yoke 61,
The pawl portion 52 and the second tooth portion 30 engage, thereby locking the rotation of the second selection ratchet 26, and the drive pawl 32 is expanded in the same manner as described above.
Second selection ratchet 26 of the rotational force of the rotating shaft 11
The rotation of the rotary shaft 11 is stopped, and the drive pawl 32 is expanded in the same manner as described above, and the transmission of the rotational force of the rotary shaft 11 to the second selection ratchet 26 and the second type wheel 14 is cut off.

Further, the type bodies provided in the type wheel (not shown) are positioned in the same manner as described above, thereby making it possible to perform the desired printing operation.

When the printing operation is completed, for example, the electromagnetic coil 56 is energized and the yoke 61 is connected to the locking claw 4.
9 and 50 are attracted, the rotation shaft 53
All you have to do is reverse it in the direction of arrow 87 in Figure 3b,
As a result, for example, the lower end portions 68, 69 of the locking claws 49, 50 rotate to overcome the bent portions 76, 77 of the spring members 66, 67,
The engagement between the locking pawls 49 and 50 and the selection latches 25 and 26 is released. Further, by reversing the rotating shaft 11 in the direction of the arrow 88 in FIG. 11, and as shown in FIG.
It is now in a state where it can be transmitted to the type wheels 13 and 14. It should be noted that exactly the same operation is performed for the locking pawls, driving pawls, selection ratchets, type wheels, etc. of other sets (not shown).

In this embodiment, the phase of the first tooth 29 of the first selection ratchet 25 and the second tooth 30 of the second selection ratchet 26 are different.
Since the selection ratchets 25 and 26 are arranged so as to shift the phase by 1/2 pitch, even if the rotation of one of the selection latches 25 and 26 is stopped, the rotation of the other one continues without being stopped; First type wheel 13
The type bodies related to the second type wheel 14 can be positioned at desired printing positions, and the rotation of these selection latches 25 and 26 can be locked by the electromagnetic coil 56, yoke 61, and rotation. Moving object 6
This can be realized by one electromagnetic clutch including 3, and the number of driving sources for stopping the rotation of the selection latches 25, 26 and the selection latches not shown in the drawings can be reduced.

Further, locking pawls 49 and 5 having pawl portions 51 and 52 that engage with teeth portions 29 and 30 of the selection latches 25 and 26 lock the rotation of the selection latches 25 and 26.
Since this is done by a zero rotational movement, the rotation of the selection latches 25 and 26, that is, the rotation of the type wheels 13 and 14, can be reliably locked.

Also, set the selection ratchets 25 and 26 to type wheel 1.
3 and 14, and guide portions 47 and 48 are provided on these selection latches 25 and 26 for rotating the drive claws 31 and 32, and the notch 12 of the rotation shaft 11 rotates the drive claws 31 and 32. The projections 35 of the first arms 37, 38 of the drive claws 31, 32 have a first surface 12a extending toward the axis O direction of the shaft 11;
36 is a second surface 4 that is adaptable to the first surface 12a.
1, 42, and when selecting type, the rotation axis 1
1, the first surface 12a of the notch 12
is configured to press the second surfaces 41, 42 of the protrusions 35, 36, that is, the rotating shaft 11
The rotational force of the rotary shaft 11 is applied to the type wheels 13, 14 through a plane orthogonal to the rotational direction of the rotary shaft 11 and almost unaffected by the frictional force between the rotary shaft 11 and the protrusions 35, 36. can be transmitted, even if the drive claws 31, 3 rotate at high speed,
2 can be suppressed to a minimum, and therefore the torque driving the rotating shaft 11 is reduced.
The motor that drives this rotating shaft 11 can be made smaller. In addition, the type wheels 13 and 14 of the drive claws 31 and 32
The installation work becomes easy, and the number of assembly work is reduced.

Further, the drive claws 31 and 32 have protrusions 35 and 36 that can be engaged with the notch portion 12 of the rotating shaft 11, and have rigid first arms 37 and 38; A second elastic body is provided integrally with the
When the drive claws 31 and 32 are attached to the type wheels 13 and 14, the second arm 3
The spring force generated by deflecting 9,40 is
Since the drive claws 31 and 32 are supported by the engagement portions between the shafts 23 and 24 and the holes 33 and 34, the positions of the drive claws 31 and 32 are stabilized, and the rotational force of the rotary shaft 11 is reliably applied to the type wheels 13 and 1.
4, and the drive claw 3
The attachment work to the type wheels 13 and 14 of Nos. 1 and 32 can be easily performed.

Also, the bearings 17, 18 serve as regulating portions for regulating the approach of the second arms 39, 40 to the bearings 17, 18.
Since the protrusions 21 and 22 are provided on the outer periphery of the drive claws 21 and 22, the drive claws 31 and 32 can be bent to have an initial setting force. In order to obtain a clamping force on the rotating shaft 11, the spring force of the drive claws 31, 32 can be set small in advance, and the manufacturing cost of these drives 31, 32 can be suppressed.

In addition, the locking claws 49 and 50 are selected from the ratchet 2
5, 26, and spring members 66, 67 that can be held in a state in which they are disengaged from the selection latches 25, 26, as described above.
By simply energizing the electromagnetic coil 56 and changing the direction of rotation of the rotating shaft 53, the locking pawls 49, 50 and the selection ratchet 25,
26, and the structure of the mechanism for returning the locking claws 49, 50 is simple.

〔Effect of the invention〕

As explained above, according to the present invention, the number of drive sources provided for locking the rotation of the type wheel can be halved compared to the conventional one. The selection of each typeface can be carried out using one driving source, and therefore, manufacturing costs can be lowered compared to the conventional method, and restrictions on component arrangement design can be relaxed.

In addition, the rotational force of the rotating shaft can be transmitted to the type wheel through a plane perpendicular to the rotational direction of the rotating shaft and almost unaffected by the frictional force between the rotating shaft and the protrusion. This allows the spring force of the drive pawl to be minimized even during high-speed rotation, thereby reducing the torque that drives the rotating shaft and making it possible to downsize the motor that drives this rotating shaft. Further, the work of attaching the drive claw to the type wheel becomes easy, and the number of assembly work can be reduced.

Further, the position of the drive claw is stabilized, the rotational force of the rotary shaft can be reliably transmitted to the type wheel, and the work of attaching the drive claw to the type wheel can be easily performed.

In addition, the drive claw can be bent to have an initial setting force by the protrusion, so it is possible to set the spring force of the drive claw to a small value in advance to obtain the clamping force against the rotating shaft. This makes it possible to reduce the manufacturing cost of these driving claws.

Furthermore, as described above, by simply energizing the electromagnetic coil and changing the direction of rotation of the rotating shaft, the engagement between the locking pawl and the selection ratchet can be released without any intervening cam member. The mechanism for returning the pawl is easy to manufacture.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view showing the main parts of an embodiment of the printer of the present invention, and FIGS. 2a and 2b show the engagement relationship between the rotating shaft and the drive pawl provided in the embodiment shown in FIG. 1. FIG. 2a is an explanatory diagram showing an engaged state in which the rotating shaft and the driving claw are engaged, and FIG. 2b is an explanatory diagram showing the disengaged state in which the rotating shaft and the driving claw are disengaged. 3A, 3B, and 3C are explanatory views showing the engagement relationship between the selection ratchet, the locking pawl, and the spring member provided in the embodiment shown in FIG. Explanatory diagram showing the standby state before the claw is driven, FIG. 3b
3 is an explanatory view showing an engaged state in which the locking pawl is engaged with the selection ratchet, and FIG. 3c is an explanatory view showing a disengaged state in which the locking pawl and the selection ratchet are not engaged. 11... Rotating shaft, 13... First type wheel, 14
...Second type wheel, 15, 16...Circumferential side, 25...
...first selection ratchet, 26...second selection ratchet, 29...first tooth section, 30...second tooth section.

Claims (1)

[Claims] 1. A rotating shaft, a first type ring attached to the rotating shaft and having a first type body on the circumferential side, and a first type ring that rotates together with the first type ring and has the first type body on the circumferential side. a first selection ratchet having a first tooth formed at a position corresponding to one type body; a second selection ratchet attached to the rotating shaft and connected to the first type ring; a second type wheel having a type body; and a second type wheel rotating together with the second type wheel and having a second tooth portion formed on the circumferential side at a position corresponding to the second type body. a ratchet, a first rigid projection having a protrusion that can be engaged with the notch of the rotating shaft;
an arm, a driving pawl formed of an elastic second arm integrally provided with the first arm, and a locking pawl in a state of engagement with the selection ratchet and a state of disengagement from the selection ratchet. a retainable spring member, and a protrusion is provided on the outer periphery of the bearing as a restriction portion that restricts the approach of the second arm of the drive claw to the bearing of the type ring of the drive claw; When the second arm is bent, the spring force generated by bending the second arm is supported by the engagement portion between the shaft of the type wheel and the hole of the drive claw, and the phase of the first tooth portion and , a first type wheel, a first selection ratchet, a second type wheel, and a second selection ratchet are arranged so that the phases of the second teeth are different from each other, and each of the drive pawls is attached to each selection ratchet. a first guide part for rotating the rotary shaft, the notch part of the rotary shaft extending in the axial direction of the rotary shaft;
The protrusion of the first arm of the driving claw has a second surface that can be adapted to the first surface, and when selecting type, the notch is rotated as the rotary shaft rotates. A printer characterized in that a first surface of the portion presses a second surface of the protrusion.