JPH1076737A - Ribbon feeding device for printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ribbon feeding device simple in construction and easy to be assembled and in which the disengagement of a pinion movable with a carriage from a rack does not occur. SOLUTION: A first holder 33 is provided in such a manner as to be freely rotated about a supporting shaft portion 28, and a pinion 34 which is brought into mesh engagement with a rack 8 is rotatably shaft supported on the first holder 33 and a second holder 36 is also rotatably shaft supported on the first holder 33. A biassing means 40 is provided for biassing the pinion 34 toward the rack 8 via the first holder 33. A first transmission gear 38 is rotatably provided at one end of the second holder 36 which is adapted to be brought into mesh engagement with and disengagement from a ribbon feeding gear 32 in accordance with clockwise and/or counterclockwise rotations of the second holder 36 which are caused depending on the rotating direction of the pinion 34, and a second transmission gear 39 which is brought into mesh engagement with the first transmission gear 38 is rotatably shaft supported at the other end of the second holder 36.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ribbon feeding device in a printer.

[0002]

2. Description of the Related Art A rack arranged along a moving direction of a carriage, a support shaft provided on the carriage, an arm rotatably provided on the support shaft, meshing with the rack and rotating at the tip of the arm. A freely movable pinion and a ribbon winding mechanism disposed on the carriage and linked to the pinion. The pinion meshing with the rack is used as a power source to rotate the ribbon winding shaft of the ribbon winding mechanism by the movement of the carriage. An example of a ribbon feeding device is described in JP-A-5-562.

In this apparatus, one end of an arm rotatably provided on a spindle provided on a carriage is connected to a print head mounting plate on which a print head is mounted, and a print head mounting plate integrated with the print head is connected to a platen. The carriage is provided with an approaching / retracting mechanism that moves in the direction of approaching / separating from the printhead. When the printhead approaches the platen by the approaching / retreating mechanism, the approaching movement of the printhead mounting plate causes When one end of the arm is retracted, the pinion meshes with the rack, and the ribbon is wound by the ribbon winding mechanism linked to the pinion, while the print head is retracted from the platen by the approach / retreat mechanism, One end of the arm is pushed down as the head mounting plate retreats, disengaging the rack and pinion, and connecting with the pinion. Ribbon winding mechanism that is what was not allowed to perform the winding of the ribbon by.

A carriage mounted with a print head and moved in the longitudinal direction of the platen is slidably fitted on the guide shaft, and the carriage is moved in the front-rear direction so as to come into contact with and separate from the platen by eccentric rotation of the guide shaft. And a pinion gear rotated with the movement of the carriage is engaged with a rack provided in the front side of the guide shaft so as to extend in the direction of movement of the carriage. The rotation of the gear causes the ink ribbon of the ink ribbon cassette mounted on the carriage to travel, and the cassette mounting base mounted on the carriage is slidably engaged with the rack, and the rack is urged toward the front by a spring. By moving the rack in the front-rear direction with the carriage, when the carriage moves in the front-rear direction, the rack is moved together with the carriage. Anion gear and rack as a printer for printing paper of various thickness as does not come off engagement is known as Japanese Patent Laid-Open No. 6-340159.

[0005] In this case, the engagement between the rack and the carriage is performed by providing a first guide groove and a second guide groove along the longitudinal direction of the rack, and a cassette mounting base provided integrally with the carriage. , A first rack engaging portion and a second rack engaging portion are respectively provided, and a second rack engaging portion is provided in the first guide groove.
The rack engaging portion is fitted and engaged with the first rack engaging portion and the second rack engaging portion so as to slidably sandwich the front wall of the rack.

The rack and the pinion meshing with the rack are slidably fitted into first and second guide grooves provided in the rack, respectively, and a slider is slidably fitted to the rack. A pinion gear provided with a large-diameter gear portion meshing with the rack is rotatably supported by a slider, and the small-diameter gear portion of the pinion gear is linked to a ribbon feed mechanism on the carriage side.

For this reason, in order to prevent the pinion gear from being disengaged from the rack, it is necessary to provide the rack with a first guide groove and a second guide groove.
Further, since the first rack engaging portion and the second rack engaging portion must be provided on the cassette mounting base, and the slider must be provided, the structure becomes complicated and the manufacturing cost is increased. Since the cassette mounting base must be engaged with the rack and the slider must be slidably fitted into the first guide groove and the second guide groove of the rack, it takes time to assemble.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a structure in which a carriage is moved without providing an engaging portion on a rack.
It is an object of the present invention to provide a ribbon feeder which can prevent a pinion and a rack which are moved together with a carriage from being disengaged from each other, has a simple structure, and can be easily assembled.

[0009]

A ribbon feeder in a printer according to the present invention is rotatably supported by a carriage, a rack disposed along the moving direction of the carriage, and a support shaft of the carriage. A ribbon feed gear, and a ribbon feed shaft provided coaxially and integrally with the ribbon feed gear, wherein a first holder is provided rotatably about the support shaft portion, and the first holder is provided on the first holder. A pinion that meshes with the rack is rotatably supported and a second holder is rotatably supported, and one end of the second holder is rotated forward and reverse by the second holder according to the rotation direction of the pinion. , A first transmission gear meshing with and disengaging from the ribbon feed gear is rotatably provided, and
The other end of the holder meshes with the first transmission gear,
When the ribbon feed gear and the first transmission gear are disengaged from each other, they mesh with the ribbon feed gear, and when the ribbon feed gear and the first transmission gear are meshed with each other, they are disengaged from the ribbon feed gear. (2) There is provided a configuration in which an urging means for rotatably supporting the transmission gear and urging the pinion toward the rack via the first holder is provided.

The first transmission gear is attached to at least a part of at least one of a gear shaft of the first transmission gear and a gear shaft of the second transmission gear provided in the second holder. And a projection for generating a braking force with respect to the rotation of the second transmission gear.

Further, the biasing means is locked at one end to a locking portion provided on the first holder, and the other end is locked at a locking portion of the carriage to direct the pinion toward the rack. It is constituted by a spring which is urged.

[0012] Further, a stopper for restricting the forward and reverse rotation of the second holder so that the engagement between the first transmission gear and the ribbon feed gear and the engagement between the second transmission gear and the ribbon feed gear are proper. Is provided on the first holder.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a main part of an impact dot printer according to one embodiment to which a ribbon feeding device of the present invention is applied, and FIG. 2 is a front view showing a carriage portion of the printer.

As shown in FIG. 1, the printer body 1 includes a left side frame 2 and a right side frame 3 which are parallel to each other and form left and right sides. A carriage shaft 4 is horizontally suspended between the left and right side frames 2 and 3, and a carriage 5 is fitted on the carriage shaft 4 so as to be slidable in the left-right direction of the printer main body 1. It is supported so as to be able to move up and down. A print head 6 is detachably attached to the carriage 5 with screws or the like with its dot pin side 6a directed vertically downward. A platen 7 that receives the impact of the dot pins of the print head 6 is disposed immediately below the path of the print head 6.

As shown in FIG. 1, an upper frame 9 having a rack 8 is horizontally provided between the upper end of the left side frame 2 and the upper end of the right side frame 3. The rack 8 is formed on the front side of the upper frame 9 vertically downward along the moving direction of the carriage 5, and the upper end of the carriage 5 is engaged with the rack 8. Although not shown in FIG. 1, at the rear of the carriage 5, when the carriage 5 moves along the rack 8, it receives power from the rack 8 and moves a ribbon feed shaft 10 described later in the ribbon feed direction. A rotating ribbon feed mechanism is provided.

As shown in FIG. 2, a ribbon feed shaft 10 is rotatably provided at the center of the upper part of the front surface of the carriage 5, and the front surface of the print pin 6 on the dot pin side 6a of the print head 6 with respect to the front surface of the carriage 5. An ink ribbon cassette 12, which feeds the ink ribbon 11 with the ink ribbon 11 interposed therebetween, is detachably mounted.

In the ink ribbon cassette 12, a pair of guide arms 12b, 12b through which the ink ribbon 11 passes project from a cassette body 12a in which the ink ribbon 11 is stored, and the print head 6 is arranged between the guide arms 12b, 12b. A hole 12c is provided, and the guide arm 12b,
The ink ribbon 11 is allowed to run with the ink ribbon 11 exposed between the leading ends of the ink ribbons 12b. The cassette body 12
An input unit (not shown) for moving the ink ribbon 11 is provided on the back side of the cartridge a. The input unit is fitted to the ribbon feed shaft 10 when the cassette body 12a is mounted on the carriage 5, and It is rotated together with the ribbon feed shaft 10.

As shown in FIG. 1, the carriage shaft 1 is provided with eccentric shaft supports 13, 13 at both ends thereof, and the left and right eccentric shaft supports 13, 13 are rotatable on the left and right side frames 2, 3, respectively. An output gear 17 of a driving force transmission mechanism 16 is formed on the outer periphery of the bearing member 15 disposed on the right side frame 3 while being axially supported at eccentric positions of the bearing 14 and the bearing member 15 provided on the right side frame 3. The eccentric shaft supports 13, 13 are rotated by a drive motor M2 that can rotate forward and reverse via a driving force transmission mechanism 16, and the platen 7 is moved within a distance corresponding to twice the eccentric dimension with respect to the axis of the carriage shaft 4. The carriage 5
And a platen 7 integrated with the carriage 5 and an ink ribbon 1 arranged on the front surface of the print head 6.
Platen 7 according to the thickness of the paper fed between
The distance between the print head 6 and the print head 6 is adjusted.

FIG. 3 is a plan view of a main part of the printer for explaining a carriage moving mechanism 18 for moving the carriage 5 in the left-right direction of the printer main body 1 along the carriage shaft 4.

The carriage moving motor M1 is disposed below a rear portion of the right side frame 3, and a drive gear 1 is mounted on a motor shaft (not shown) of the carriage moving motor M1.
9 is fixed. Above the motor shaft, a support shaft 20 parallel to the motor shaft is rotatably supported between the auxiliary plate 31 and the rear wall 3a of the right side frame 3.
A transmission gear 21 that meshes with the drive gear 19 and a transmission pulley 22 that is coaxial with the transmission gear 21 are rotatably supported.

A support member 23 is provided inside the left side frame 2.
The driven pulley 24 which is paired with the transmission pulley 22 disposed on the right side frame 3 side is rotatably supported by the support member 23. A timing belt 25 is wrapped around the transmission pulley 22 and the driven pulley 24 and stretched in the left-right direction of the printer main body 1, and a rear portion of the carriage 5 is connected and fixed to the upper side of the timing belt 25.

The carriage moving mechanism 18 rotates the transmission pulley 22 coaxial with the transmission gear 21 via the drive gear 19 and the transmission gear 21 by the forward / reverse rotation of the motor shaft of the carriage moving motor M1. Belt 25 between the printer 1 and the driven pulley 24
Of the printer 5 together with the timing belt 25 in the left-right direction.
To reciprocate.

Next, the ribbon feeding mechanism provided on the carriage 5 will be described. FIG. 4 is a partial front view of a carriage including the ribbon feeding device according to one embodiment of the present invention. FIG. 5 is an enlarged front view of a main part of FIG. 4 including a ribbon feeding mechanism.

As shown in FIG. 4, a support holder 26 is attached to the upper rear side of the carriage 2, and a ribbon feed mechanism 27 is provided on the support holder 26. FIG.
7 is a front view of the support holder 26, and FIG. 7 is a plan view of the support holder 26.

As shown in FIG. 6, the support holder 26 has a horizontally long rectangular shape. As shown in FIG. 6 and FIG. The supporting pieces 29, 29, 29, 2 formed to extend forward are provided on the left and right side edges near the upper end and the lower end.
9 are provided.

As shown in FIG. 7, locking pawls 30 are respectively provided inside the distal ends of the support pieces 29, and each of the locking pawls 30 has a tapered portion inclined inward from the distal end. 30a and a flat locking portion 30b formed below the tapered portion 30a.

As shown in FIG. 4, a ribbon feed shaft 10 protruding from the front surface of the carriage 5 and fitted to the input portion of the ribbon cassette 12 is coaxially mounted on a support shaft 28 provided on the support holder 26. An integrally provided ribbon feed gear 32 is rotatably provided, and a first holder 33 is rotatably supported by a shaft. As shown in FIG. 4, a pinion 34 that meshes with the rack 8 is rotatably supported by the first holder 33 via a shaft 35 integrated with the pinion 34.
The holder 36 is rotatably supported via the swing shaft 37.

As shown in FIG. 5, the second holder 36 has a swing shaft 37 at an intermediate portion thereof, and the swing shaft 37
It is rotatably supported by the holder 33. Second holder 3
6, one end of the second holder 36 according to the forward / reverse rotation of the second holder 36 in accordance with the rotation direction of the pinion 34 meshing with the rack 8.
A first transmission gear 38 that meshes with and disengages from the ribbon feed gear 32 is rotatably provided. The other end of the second holder 36 is always meshed with the first transmission gear 38, When the transmission gear 38 is disengaged from the transmission gear 38, the transmission gear 38 is engaged with the ribbon transmission gear 32. When the transmission gear 38 is engaged with the first transmission gear 38, the ribbon transmission gear 32 is engaged.
A second transmission gear 39 that meshes with and is rotatably supported.

As shown in FIG. 4, a torsion coil spring 40 for urging a pinion 34 axially supported by the first holder 33 through the first holder 33 toward the rack 8 is provided at a rear portion of the upper portion of the carriage 5. Is provided.

When the carriage 5 moves along the rack 8, the ribbon feed mechanism 2 receives power from the rack 8 and rotates the ribbon feed shaft 10 in the ribbon feed direction.
7 is a first holder 3 rotatably supported by a support shaft 28.
3 and the rack 8 and the first holder 33
5, a pinion 34 rotatably supported by the first holder 33 via a swinging shaft 37, a second holder 36 rotatably supported by the first holder 33, and a rotatable one end of the second holder 36. And a second transmission gear 39 rotatably supported at the other end of the second holder 36.

As shown in FIG. 5, the first holder 33 has a pair of front and rear front and rear plate portions 41 and 4 facing in parallel with each other.
2 and a side plate portion 43 forming a side surface between one side edge of the front plate portion 41 and one side edge of the rear plate portion 42. The rear plate portion 42 extends obliquely downward from the other side edge and has an arm portion 44.
Is formed, and a shaft hole 45 for inserting the shaft 28 provided in the support holder 26 is provided near the tip of the arm 44. Also, as shown in FIG.
An insertion hole 46 through which one end of the torsion coil spring 40 is inserted is provided in the side plate portion 43 of the holder.

As shown in FIG. 5, the rack 8 is located between the upper edge of the front plate portion 41 of the first holder 33 near the other side edge and the upper edge of the rear plate portion 42 near the other side edge. Pinion 3 meshing
4 is rotatably supported, and a pinion is provided between the lower edge of the front plate portion 41 of the first holder 33 near the other side edge and the lower edge of the rear plate portion 42 near the other side edge. A swinging shaft 37 of a second holder 36 is rotatably supported in parallel with the shaft 35 of 34. Further, on the inner surface of the rear plate portion 42, a first stopper 67 and a second stopper 68 which face the side of the second holder 36 and regulate the forward / reverse rotation of the second holder 36 about the swing shaft 37.
Is provided.

FIG. 8 is a sectional view of a main part of FIG. As shown in FIG. 8, the pinion 34 is disposed closer to the front plate 41 of the first holder 33, and the pinion 34 is positioned closer to the shaft 35 of the pinion 34 closer to the rear plate 42 of the first holder 33 than the pinion 34 is. A small-diameter coaxial transmission gear 47 is integrally formed coaxially with the pinion 34, and the pinion 34 and the coaxial transmission gear 47 are rotatably supported integrally with the shaft 35 near the upper end of the first holder 33.

FIG. 9 is a vertical sectional view of the second holder 36.
FIG. 10 is a cross-sectional view of the second holder. 9 to 1
As shown in FIG. 0, the second holder 36 is
8 and a holder second member 49.

As shown in FIG. 9, a pair of locking pieces 50, 50 and a pair of locking pieces 51, 5 facing each other are provided on both sides of the inner surface of the holder base 48a of the holder first member 48.
1 are respectively protruded toward the inside of the second holder. As shown in FIG. 10, each of the pair of locking pieces 50, 50 and 51, 51 has an arc-shaped cross section on the side facing the outside opposite to the surface facing each other. As shown in FIG. 9, locking claw portions 5 are provided at the tips of the pair of locking pieces 50, 50.
2 and 52 are respectively provided, and a pair of locking pieces 51 and 51 are provided.
Are provided with locking claw portions 53, 53, respectively. The locking claw portion 52 includes a tapered portion 52a that is inclined outward from the tip and a locking claw 52b that is formed to project downward from the tapered portion. The locking claw portion 53 includes a tapered portion 53a inclined outward from the tip and a locking claw 53b formed to project downward from the tapered portion.

The pair of locking pieces 50, 50 and the locking pieces 51, 51 are such that the locking claw portions 52, 52 at their tips can be elastically deformed toward the inside facing each other. The locking claw portions 53 at the front end can be elastically deformed toward the inside. In the center of the outer surface of the holder base 48a of the first holder member 48, a shaft support 54 is formed in a convex shape.

As shown in FIG. 10, a cylindrical first transmission gear shaft portion 55 protrudes from one side of the inner surface of the holder base 49a of the holder second member 49 of the second holder 36 so as to protrude. On the other side of the inner surface of the holder base 49a of the two members 49, a cylindrical second transmission gear shaft portion 56 is provided so as to protrude therefrom.
A pair of locking pieces 5 of the holder first member 48 are respectively provided inside the transmission gear shaft 55 and inside the second transmission gear shaft 56.
A through-hole 57 and a through-hole 58 for inserting the pair of locking pieces 51, 51 and the pair of locking pieces 51, 51 respectively are provided.

As shown in FIG. 10, the first transmission gear shaft 5
5 is provided on a part of the peripheral surface thereof with a projection 59 slightly projecting from the peripheral surface of the gear shaft 55 in an arc-shaped cross section. As shown in FIG. 9, the swing shaft 3 of the second holder 36 is provided at the center of the outer surface of the holder base 49a of the holder second member 49.
7 is protruded, and a shaft support 6 is provided at the tip of the swing shaft 37.
0 is formed.

As shown in FIG. 10, the holder second member 49
The gear hole 61 of the first transmission gear 38 is inserted through the first transmission gear shaft portion 55, and the gear hole 62 of the second transmission gear 39 is inserted through the second transmission gear shaft portion 56 of the holder second member 49. The first transmission gear 38 and the second transmission gear 39 are engaged with each other, and a through hole 57 provided inside the first transmission gear shaft portion 55 of the holder second member 49 as shown in FIG. The pair of locking pieces 50, 50 of the holder first member 48 are inserted into the second transmission gear shaft portion 56 of the holder second member 49.
The pair of locking pieces 51, 51 of the holder first member 48 are inserted into through holes 58 provided inside the
On the outside of the holder base 49a of the holder second member 49, the locking claws 52, 5 at the tips of the pair of locking pieces 50, 50.
2, a locking claw 53 at the tip of a pair of locking pieces 51, 51,
53 are respectively protruded, and the locking claw 5
2b and 52b are hooked, and the locking claws 53b and 53b are hooked on the peripheral edge of the through hole 58 so that the first holder member 48
And the second holder member 49 are engaged.

As shown in FIG. 10, the second holder 36
The first transmission gear 38 is rotatably supported by the first transmission gear shaft 55 at one end of the second holder 36, and the second transmission gear 39 is supported by the second transmission gear shaft 56 at the other end of the second holder 36. The first transmission gear 38 and the second transmission gear 3 are rotatably supported and are always rotatable.
9 is maintained in an engaged state, and the inner peripheral surface of the gear hole 61 of the first transmission gear 38 is pressed against a protrusion 59 provided on a part of the peripheral surface of the first transmission gear shaft portion 55, and at the same time, The first transmission gear shaft 55 has a first side opposite to the projection 59 with respect to the center of the first transmission gear shaft 55.
The gear hole 6 of the first transmission gear 38 is formed in the peripheral surface of the transmission gear shaft 55.
1 is pressed into contact with the inner peripheral surface of the first transmission gear 38.
Transmission gear 3 meshing with the rotation of the first transmission gear 38
9 to generate a braking force.

As shown in FIG. 8, the second holder 36 has a shaft support 54 provided at the center of the outer surface of the holder first member 48 rotatably supported by the rear plate 42 of the first holder 33. The pivot 60 at the tip of the swing shaft 37 provided at the center of the outer surface of the holder second member 49 is connected to the front plate 41 of the first holder 33.
The first holder 33 is rotatably supported near the rear plate portion 42 of the first holder 33 so as to be swingable about a swing shaft 37.
A first transmission gear 38 rotatably provided at one end of the second holder 36 is always meshed with a coaxial transmission gear 47 provided coaxially with the pinion 34 meshing with the rack 8, and a first transmission gear 38 corresponding to the rotation direction of the pinion 34. A second transmission gear 39 rotatably provided at the other end of the second holder 36 is configured to mesh with and disengage from the ribbon feed gear 32 according to the forward / reverse rotation of the second holder 36. When the first transmission gear 38 meshes with the first transmission gear 38, the first transmission gear 38 meshes with the ribbon transmission gear 32 when the ribbon transmission gear 32 is disengaged from the first transmission gear 38. It is configured to engage and disengage with the ribbon feed gear 32.

The first holder 33 shown in FIGS.
When the first stopper 67 and the second stopper 68 provided on the rear plate portion 42 rotate forward and backward of the second holder 36 in accordance with the rotation direction of the pinion 34, the holder first member of the second holder 36. 48 so that the first transmission gear 38 of the second holder 36 meshes with the ribbon feed gear 32 and the second transmission gear 39 meshes with the ribbon feed gear 32 so that the second holder 36 is properly oriented. Regulate reverse rotation.

As shown in FIG. 4, the carriage 5 is provided with an insertion hole (not shown) through which the ribbon feed shaft 32 is inserted from the front to the rear, and the four support pieces 29, 29, Lock holes 6 at positions corresponding to 29, 29
3, 63, 63, 63 are provided from the front to the rear, respectively.
9 is provided with a locking step portion 64 for locking the locking portion 30 b of the ribbon feed gear 3 on the support shaft portion 28 of the support holder 26.
2 and the first holder 33 provided with the second holder 36 and the pinion 34 are rotatably supported by the support holder 2.
6, four support pieces 29, 29, 29, 29 are provided from the rear side of the carriage 5 to the four locking holes 63, 63, 63,
63, 63, and each support piece 29
The engaging portion 30b is engaged with an engaging step 64 inside the engaging hole 63 of the carriage 5, and the support holder 26 is attached to the upper rear portion of the carriage 5.

As shown in FIG. 5, the cylindrical portion of the torsion coil spring 40 is inserted into a columnar spring mounting projection 65 protruding toward the rear of the carriage 5, and one end of the torsion coil spring 40 is The other end of the torsion coil spring 40 is inserted into the rear end of the carriage 5 while being inserted into the insertion hole 46 provided in the side plate portion 43 of the holder 33 and locked at the edge of the insertion hole 46, as shown in FIG. Projecting wall 66 projecting toward
The first holder 33 is pivoted around the support shaft 28 by the bias of the torsion coil spring 40 as shown in FIG.
In FIG. 5, a bias is applied in a counterclockwise direction so that the meshing state between the rack 8 and the pinion 34 is always maintained.
The pinion 34 rotatably supported by the first holder 33 via the first holder 33 is urged toward the rack 8.

Next, the operation of the present embodiment will be described.
FIG. 5 is a schematic front view of the ribbon feed mechanism 27 showing a state in which the first transmission gear 38 of the second holder 36 meshes with the ribbon feed gear 32, and FIG. 11 shows the first transmission gear of the second holder 36. The gear 38 disengages from the ribbon feed gear 32,
FIG. 4 is a schematic front view showing a state in which a second transmission gear 39 is meshed with a ribbon feed gear 32 and a part of the ribbon feed mechanism 27 is cut away.

First, the ribbon feeding operation of the ribbon feeding device 27 accompanying the horizontal movement of the carriage 5 will be described. As a premise, as shown in FIG. 5, the first transmission gear 38 of the second holder 36 that is supported by the first holder 33 is coaxially formed integrally with the pinion 34.
And the ribbon feed gear 32. Note that the first stopper 67 provided on the first holder 33 abuts on the side edge of the second holder 36 to restrict the rotational position of the second holder 36. In this state, the first transmission gear 38 and the ribbon The engagement with the feed gear 32 is properly maintained.

When the carriage moving motor M1 shown in FIG. 3 is driven to rotate forward, the carriage 5 is moved along the carriage shaft 4 in FIG. When the carriage moving motor M1 rotates in the reverse direction, the carriage 5 moves in FIG.
Move along the carriage shaft 4 to the right as indicated by the chain line arrow B.

In FIG. 2, the carriage moving motor M
When the carriage 5 moves to the left along the carriage shaft 4 by the forward rotation of the carriage 1, as shown in FIG.
The first holder 33 rotatably supported on the carriage 5
Along with the rack 8 to the left as indicated by the arrow A,
The pinion 34 rotatably provided on the first holder 33 is engaged with the rack 8 and the arrow A together with the first holder 33.
As a result of moving to the left indicated by the arrow A, the first
As the holder 33 moves, the pinion 34 and the coaxial transmission gear 47 formed coaxially and integrally with the pinion 34
5, and rotates clockwise as indicated by the solid arrow.

At the same time, the clockwise rotation of the pinion 34, that is, the clockwise rotation of the coaxial transmission gear 47 coaxial with and integral with the pinion 34, is transmitted to the first transmission gear 38 meshing with the coaxial transmission gear 47, The first transmission gear 38 rotates counterclockwise as indicated by the solid arrow.

Further, the first holder 36 supported by the second holder 36
The counterclockwise rotation of the transmission gear 38 rotates the first transmission gear 38
The transmission is transmitted to the ribbon transmission gear 32 and the second transmission gear 39 constantly engaged with the first transmission gear 38 in the meshing state with the ribbon transmission gear 32 and the ribbon transmission shaft 10 (not shown) about the support shaft portion 28. Turning clockwise in FIG.
The ink ribbon 11 of the ink ribbon cassette 12 is fed in the winding direction, and the second transmission gear 39 in FIG.
Rotates clockwise in a free state.

In FIG. 2, a carriage moving motor M
When the carriage 5 is moved rightward along the carriage shaft 4 along the carriage shaft 4 by the forward rotation of the carriage 5 from the forward rotation drive, the carriage 5 in FIG.
First holder 33 rotatably supported by the supporting shaft 28 on the side
Moves together with the carriage 5 to the right along the rack 8 as indicated by the arrow B, and the pinion 34 rotatably provided on the first holder 33 engages with the first holder 3 while engaging with the rack 8.
As a result of the movement of the first holder 33 to the right as shown by the arrow B as a result of the pinion 34
The coaxial transmission gear 47, which is coaxial with and integral with the pinion 34, rotates together with the shaft 35 in a counterclockwise direction indicated by a chain line arrow.

At the same time, the pinion 34 rotates counterclockwise, that is, the coaxial transmission gear 47 integrated with the pinion 34.
Is transmitted in a direction in which the first transmission gear 38 meshing with the coaxial transmission gear 47 is rotated clockwise. The first transmission gear 38 is provided with a braking force in a clockwise rotation about the first transmission gear shaft 55 by a protrusion 59 provided on a part of the peripheral surface of the first transmission gear shaft 55 shown in FIG. Since it is engaged, it does not rotate clockwise, and thus the second transmission gear 39 does not rotate. Therefore, the counterclockwise rotation of the coaxial transmission gear 47 is rotated via the first transmission gear 38 in the second holder 36. , The second holder 36 rotates clockwise about the pivot shaft 37 as shown by the solid arrow C in FIG.

As a result, one end of the second holder 36 is separated from the ribbon feed gear 32, and the other end of the second holder 36 approaches the ribbon feed gear 32.
With the clockwise rotation about the swing shaft 37 of the second holder 36, the engagement between the first transmission gear 38 and the ribbon feed gear 32, which is supported by one end of the second holder 36, is disengaged, and the second holder 36 The second transmission gear 39 supported at the other end of the ribbon feed gear 3
2 (see FIG. 11).

As shown in FIG. 11, the clockwise rotation of the second holder 36 about the swing shaft 37 is performed by the second holder 3.
6 is stopped by the side edge near one end abutting on the second stopper 68 provided on the first holder 33 and regulated. At this time, the second holder 36 supported by the other end of the second holder 36
The transmission gear 39 meshes with the ribbon feed gear 32, and the mesh between the second transmission gear 39 and the ribbon feed gear 32 is maintained in an appropriate state.

As shown in FIG. 11, when the clockwise rotation of the second holder 36 about the swing shaft 37 is stopped, the counterclockwise rotational force of the coaxial transmission gear 47 changes to the first transmission. As a result of exceeding the braking force by the protrusion 59 provided on a part of the peripheral surface of the gear shaft 55, the first transmission gear 38 rotates clockwise around the first transmission gear shaft 55 as indicated by a broken arrow.

The clockwise rotation of the first transmission gear 38 pivotally supported by the second holder 36 is constantly transmitted to the second transmission gear 39 meshed with the first transmission gear 38, and further meshed with the second transmission gear 39. The state is transmitted to the ribbon feed gear 32 in the state, and the ribbon feed gear 32 and the ribbon feed shaft 10 (not shown) rotate clockwise in FIG. 11 around the support shaft 28 provided on the first holder 33. Then, the ink ribbon 11 of the ink ribbon cassette 12 in FIG. 2 is fed in the winding direction.

As shown in FIG. 11, the first transmission gear 38 pivotally supported at one end of the second holder 36 pivotally supported by the first holder 33 is disengaged from the ribbon feed gear 32, and A second shaft supported at the other end of the second holder 36
In FIG. 2, when the transmission gear 39 is in mesh with the ribbon feed gear 32, the carriage 5 moves to the left along the carriage shaft 4 along the carriage shaft 4 by the forward rotation of the carriage moving motor M1 from the reverse rotation drive. 11, the first holder 33 rotatably supported by the support shaft 28 on the carriage 5 side moves to the left along the rack 8 along the rack 8 to the left as shown by the arrow A in FIG. The pinion 11 rotatably provided on the first holder 33 moves to the right as shown by the arrow A together with the first holder 33 while meshing with the rack 8, and as a result, the pinion 11 moves to the right as shown by the arrow A A coaxial transmission gear 47 coaxial with the pinion 34 and the pinion 34 rotates together with the shaft 35 in a clockwise direction indicated by a solid arrow.

At the same time, the clockwise rotation of the pinion 34, ie, the clockwise rotation of the coaxial transmission gear 47 integral with the pinion 34, rotates the first transmission gear 38 meshing with the coaxial transmission gear 47 counterclockwise. Is transmitted in the direction of
The first transmission gear 38 has a first transmission gear shaft 55 shown in FIG.
Since the braking force is applied to the counterclockwise rotation about the first transmission gear shaft 55 by the projection 59 provided on a part of the peripheral surface of the first transmission gear shaft 55, the rotation is not performed in the counterclockwise direction. The second transmission gear 39 also does not rotate. Therefore, the clockwise rotation of the coaxial transmission gear 47 is transmitted to one end of the second holder 36 via the first transmission gear 38, and the second holder 36 As a result, the one end of the second holder 36 approaches the ribbon feed gear 32 and the second holder 36 rotates as shown in FIG.
Of the second holder 3 is separated from the ribbon feed gear 32.
The first transmission gear 3 pivotally supported on one end of the second holder 36 with the counterclockwise rotation about the swing shaft 37 of the second holder 36.
8 meshes with the ribbon feed gear 32, and the second transmission gear 39 and the ribbon feed gear 32 supported at the other end of the second holder 36.
Is disengaged (see FIG. 5).

The counterclockwise rotation of the second holder 36 about the swing shaft 37 is performed by moving the side edge of the second holder 36 near the other end to the first stopper 67 provided on the first holder 33. Stop by being abutted and regulated. At this time, the second
The first transmission gear 38 pivotally supported at one end of the holder 36 meshes with the ribbon feed gear 32, and the mesh between the first transmission gear 38 and the ribbon feed gear 32 is maintained in an appropriate state.

As shown in FIG. 5, when the counterclockwise rotation of the second holder 36 about the swing shaft 37 is stopped, the clockwise rotational force of the coaxial transmission gear 47 changes to the first transmission. As a result of exceeding the braking force by the protrusion 59 provided on a part of the peripheral surface of the gear shaft 55, the first transmission gear 38 rotates counterclockwise around the first transmission gear shaft 55 as indicated by the solid arrow.

The counterclockwise rotation of the first transmission gear 38 pivotally supported by the second holder 36 causes the ribbon transmission gear 32 meshed with the first transmission gear 38 and the first transmission gear 3
8, the ribbon transmission gear 32 and the ribbon transmission shaft 10 (not shown) are transmitted to the second transmission gear 39 meshed with the support shaft 2.
5, the ink ribbon 11 of the ink ribbon cassette 12 shown in FIG. 2 is rotated in the winding direction while the second transmission gear 39 is rotated clockwise in a free state.

Next, the distance between the platen 7 and the print head 6 depends on the thickness of the paper fed between the platen 7 integrated with the carriage 5 and the ink ribbon 11 arranged on the front surface of the print head 6. The case where the carriage 5 is moved in the vertical direction to approach / separate from the platen 6 in order to adjust the distance of the carriage 5 will be described. The range of the movement amount of the carriage 5 is 0.3 to 2.0 mm.

FIG. 4 is a view showing a state in which the carriage 5 having the print head 6 shown in FIG. FIG. 12 is a view showing a state in which the carriage 5 having the print head 6 shown in FIG.

When the carriage 5 moves upward from the position shown in FIG. 4 so as to be separated from the platen 7, the carriage 5 moves upward as shown by a solid arrow E in FIG. With the upward movement indicated by E, the support shaft 28 on the side of the carriage 5 moves upward as indicated by the arrow E, and the carriage 5 moves closer to the rack 8 so that the support shaft 28 becomes the first holder. 33 arms 4
4 is pushed upward in FIG. 4, and the rack 8 is pushed against the bias of the torsion coil spring 40.
As a result of pressing the pinion 34 meshing with the lower part downward, the first holder 33 rotates clockwise about the support shaft part 28 while pressing and shrinking the torsion coil spring 40 in accordance with the upward movement amount of the carriage 5. Thus, the engagement between the pinion 34 pivotally supported by the first holder 33 and the rack 8 is maintained.

When the upward movement of the carriage 5 indicated by the arrow E is stopped, the rotation of the first holder 33 and the pinion 34 are stopped.
Stops at the same time. When the carriage 5 moves upward, the urging force of the torsion coil spring 40 maintains the engagement between the pinion 34, which is moved upward together with the carriage 5, and the rack 8, without changing the posture of the first holder 33 in FIG. Is determined as shown in

When the carriage 5 is moved from the position shown in FIG.
When the carriage 5 moves downward to approach the platen 7, the carriage 5 moves to the lower side indicated by the solid arrow F shown in FIG. The support shaft 28 on the carriage 5 side
Moves downward as indicated by arrow F, the carriage 5 moves in a direction away from the rack 8, and the support shaft 28
The distal end of the arm portion 44 of the holder 33 is pulled downward in FIG. 12, and the first holder 33 is pushed up toward the rack 8 by the return force of the torsion coil spring 40. FIG. 1 shows that one holder 33 faces the rack 8 with the spindle 28 as the center.
2 and the first holder 3
Engagement of the pinion 34 and the rack 8 supported by the shaft 3 is maintained.

When the downward movement of the carriage 5 is stopped as indicated by the arrow F, the rotation of the first holder 33 and the pinion 3
4 stops simultaneously. When the carriage 5 moves downward, the first holder 33 is maintained by the urging of the torsion coil spring 40 while the engagement between the pinion 34 moved with the carriage 5 and the rack 8 is maintained without being disengaged.
Is determined as shown in FIG.

As described above, according to the ribbon feeder of the embodiment, when the carriage 5 moves vertically, the first
When the holder 33 rotates and the first holder 33 rotates,
By the urging of the torsion coil spring 40, the engagement between the pinion 34 moved together with the carriage 5 and the rack 8 can be maintained without being disengaged, and it is necessary to provide the rack 8 with an engaging portion that specifically engages with the carriage 5. Further, since a structure for directly engaging the rack 8 and the carriage 5 is not required, the structure is simple and the assembly is easy.

Also, the state in which the carriage 5 having the print head 6 shown in FIG. 4 is closest to the platen 7 and the state in which the carriage 5 having the print head 6 shown in FIG. In any case, the first holder 33 that supports the pinion 34 that meshes with the rack 8 is rotatably supported by the support shaft 28 provided near the upper edge of the carriage 5. As a result, the contact angle when the pinion 34 meshes with the rack 8 can be set to a direction substantially perpendicular to the rack 8. Therefore, the rack 8 and the pinion can be moved according to the left and right movement directions of the carriage 5. The balance of the load at the time of meshing of the gears 34 can be improved.

[0070]

According to the ribbon feeder in the printer of the present invention, when the carriage moves in the up-down direction, the first position is set.
The holder is rotated, and when the first holder is rotated, the engagement between the pinion and the rack moved together with the carriage can be maintained without being disengaged by the urging of the urging means. There is no need to provide a mating engaging portion, and a structure for directly engaging the rack and the carriage is not required, so that the structure is simple and assembly is easy. Further, since the first holder, the pinion, the second holder, the first transmission gear, the second transmission gear, and the urging means are configured, the number of parts can be reduced.

Further, according to the ribbon feeder of the printer according to the fourth aspect, the stopper for restricting the forward / reverse rotation of the second holder is provided on the first holder, so that the first holder is provided.
The meshing between the transmission gear and the ribbon feeding gear and the meshing between the second transmission gear and the ribbon feeding gear can be maintained in proper meshing so as not to increase the rotational load.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a main part of an impact dot printer according to an embodiment to which a ribbon feeder of the present invention is applied.

FIG. 2 is a front view showing a carriage portion of the printer according to the first embodiment;

FIG. 3 is a plan view of a main part of the above printer.

FIG. 4 is a partial front view of a carriage including a ribbon feeding device according to an embodiment of the present invention (a state in which a carriage on which a print head is mounted is closest to a platen).

FIG. 5 is an enlarged front view of a main part of FIG. 4 including a ribbon feed mechanism (a state where a first transmission gear of a second holder is meshed with a ribbon feed gear).

FIG. 6 is a front view of a support holder.

FIG. 7 is a plan view of a support holder.

8 is a sectional view of a main part of FIG. 5;

FIG. 9 is a longitudinal sectional view of a second holder.

FIG. 10 is a cross-sectional view of the second holder.

FIG. 11 is a schematic front view showing a part of the ribbon feed mechanism in a cutaway state (a state in which a first transmission gear of a second holder is disengaged from the ribbon feed gear and a second transmission gear is engaged with the ribbon feed gear).

FIG. 12 is a partial front view of a carriage including a ribbon feeding device according to an embodiment of the present invention (a state where a carriage on which a print head is mounted is most separated from a platen).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printer main body 2 Left side frame 3 Right side frame 3a Rear wall 4 Carriage shaft 5 Carriage 6 Printing head 7 Platen 8 Rack 9 Upper frame 10 Ribbon feed shaft 11 Ink ribbon 12 Ink ribbon cassette 12a Cassette body 12b Guide arm 12c Through hole 13 Eccentricity Shaft support 14 Bearing 15 Bearing material 16 Driving force transmission mechanism 17 Output gear 18 Carriage moving mechanism 19 Drive gear 20 Support shaft 21 Transmission gear 22 Transmission pulley 23 Supporting material 24 Follower pulley 25 Timing belt 26 Support holder 27 Ribbon feeding mechanism 28 Support shaft Part 29 Supporting piece 30 Locking claw part 30a Taper part 30b Locking part 31 Auxiliary plate 32 Ribbon feed gear 33 First holder 34 Pinion 35 Axis 36 Second holder 37 Oscillating axis 38 First transmission Gear 39 Second transmission gear 40 Torsion coil spring 41 Front plate portion 42 Rear plate portion 43 Side plate portion 44 Arm portion 45 Support shaft hole 46 Insertion hole 47 Coaxial transmission gear 48 Holder first member 48a Holder base 49 Holder second member 49a Holder base REFERENCE SIGNS LIST 50 locking piece 51 locking piece 52 locking claw 53 locking claw 54 shaft support 55 first transmission gear shaft 56 second transmission gear shaft 57 through hole 58 through hole 59 protrusion 60 shaft support 61 gear hole 62 gear hole 63 locking hole 64 locking step 65 spring arranging projection 66 protruding wall 67 first stopper 68 second stopper M1 carriage moving motor M2 drive motor

Claims (4)

[Claims] 1. A carriage, a rack disposed along a moving direction of the carriage, a ribbon feed gear rotatably supported by a support shaft of the carriage, and a coaxial integral part of the ribbon feed gear. And a ribbon feed shaft provided in the printer, wherein a first holder is provided rotatably around the support shaft portion,
A pinion that meshes with the rack is rotatably supported on the first holder, and a second holder is rotatably supported on the second holder;
At one end of the second holder, a first transmission gear that meshes with and disengages from the ribbon feed gear is rotatably provided in accordance with the forward / reverse rotation of the second holder according to the rotation direction of the pinion. The other end of the holder 2 meshes with the first transmission gear, and meshes with the ribbon feed gear when the ribbon transmission gear and the first transmission gear are disengaged from each other. Urging means for rotatably supporting a second transmission gear which meshes with and disengages from the ribbon feed gear when the transmission gear meshes with the ribbon feed gear and urges the pinion toward the rack via the first holder; A ribbon feeding device in a printer, wherein the ribbon feeding device is provided. 2. The first transmission gear, wherein a part of at least one of a gear shaft of the first transmission gear and a gear shaft of the second transmission gear disposed on the second holder is provided. 2. The ribbon feeding device according to claim 1, further comprising a projection for generating a braking force with respect to the rotation of the second transmission gear and the rotation of the second transmission gear. 3. The pinion is directed toward the rack by locking one end of the biasing means to a locking portion provided on the first holder and locking the other end to a locking portion of the carriage. 2. The ribbon feeding device according to claim 1, wherein the ribbon feeding device comprises a spring biased. 4. A stopper for restricting the forward and reverse rotation of the second holder so that the engagement between the first transmission gear and the ribbon feed gear and the engagement between the second transmission gear and the ribbon feed gear are proper. The ribbon feeding device according to claim 1, wherein the ribbon feeding device is provided on the first holder.