JPH07401B2 - Serial printer - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a serial printer that prints by a print head mounted on a carriage while moving the carriage in the horizontal direction.

[Conventional technology]

A conventional carriage movement method in this type of serial printer is to connect a carriage equipped with a print head to a part of a toothed belt or wire rope, and transfer the toothed belt or wire rope by a motor. There is a method of moving the carriage, or a method of passing a screw shaft that meshes with the carriage and rotating the screw shaft by a motor to move the carriage.

As described above, in the conventional apparatus, the toothed belt, the wire rope, the screw shaft, or the like, which is a power transmission means, is interposed between the carriage and the motor, which is the drive source for the movement, and therefore the following drawbacks are caused. Have

That is, in the above-described conventional structure, the driving force of the motor does not act directly on the carriage, resulting in power loss of the motor, and the expansion and deformation of the toothed belt, the wire rope, the screw shaft, etc., which are power transmission means. This causes variations in the movement positioning accuracy.

Further, since the component structure is complicated, the assembly is troublesome and time-consuming, and the component mounting space becomes large, which hinders the cost reduction and size reduction of the product.

[Object of the Invention]

The present invention solves the conventional drawback by directly applying a driving force of a motor to a carriage equipped with a print head, and at the same time, provides a serial printer capable of driving an ink ribbon by a motor for moving a carriage. Aim to achieve.

[Structure of Invention]

In order to achieve this object, the present invention is a serial printer in which a carriage having a print head and a ribbon cartridge having an ink ribbon running on the front end surface of the print head is horizontally moved. A rotor shaft integrally formed with a flat rotor magnet having poles alternately magnetized is rotatably attached to the carriage at one end thereof so as to be substantially orthogonal to a horizontal plane formed by horizontal movement of the carriage, and the rotor magnet and A flat DC brushless motor mounted on the lower surface of the carriage is configured by fixing stator coils annularly arranged in the circumferential direction of the rotor shaft so as to face each other to the carriage, and a pinion is provided below the rotor shaft. And guide the movement of the carriage through the rack that engages with this pinion. A ribbon transmission power transmission mechanism, which is provided in parallel with the idler, has an output gear attached to the upper portion of the rotor shaft, and meshes with the output gear to transmit the rotational force to the ink ribbon of the ribbon cartridge on the carriage. It is characterized by being provided.

〔Example〕

 Embodiments will be described below with reference to the drawings.

FIG. 1 is a perspective view of an essential part showing an embodiment of a serial printer according to the present invention. In the figure, 1 is a carriage, 2 is edges of front and rear portions of the carriage 1, 3 is a print head mounted on the carriage 1, and 4 is a print head. Similarly, a ribbon cartridge 5 mounted on the carriage 1 is an ink ribbon. Most of the ink ribbon 5 is housed in the ribbon cartridge 4, and a part of the ribbon is run so as to run across the front end surface of the print head 3. It is exposed to the outside of the cartridge 4.

6 is a guide rail whose front and rear ends are folded up in an L shape,
The front and rear edges 2 of the carriage 1 are fitted to the front and rear ends of the guide rail 6, so that the carriage 1 is guided by the guide rail 6 in the horizontal movement.

7 is a rack fixed in the guide rail 6 so as to be parallel to the guide rail 6, and 8 is a flexible cord,
The flexible cord 8 is formed by extending a part of a flexible substrate, which will be described later, fixed to the bottom surface of the carriage 1. The flexible cord 8 supplies and receives signals for power supply and print control.

FIG. 2 is an exploded perspective view of a flat DC brushless motor used as a drive source for moving the carriage 1 in the horizontal direction. The flat DC brushless motor is composed of a rotor portion 16 and a stator portion 21.

The rotor portion 16 is composed of 9 to 15 components, 9 is a rotor shaft, 10 is a flange of the rotor shaft 9, 11 is a pinion,
Reference numeral 12 is a timing slit disk, 13 is a slit for rotor rotation position detection formed in a large number at the peripheral edge of the timing slit disk 12 at equal intervals, 14 is a rotor yoke, and 15 is an N pole and an S pole arranged alternately. As described above, the rotor magnet 15 is directly magnetized, and the rotor magnet 15 is fixed on the rotor yoke 14. The rotor yoke 14 is fixed together with the timing slit disk 12 coaxially to the flange 10 about the rotor shaft 9, and further to the rotor shaft. A pinion 11 is fixed to the lower part of 9 to form a rotor section 16.

On the other hand, the stator portion 21 is composed of 17 to 20 constituent elements,
17 is a stator yoke having a hole in the center, 18 is a rotor portion 16
, 19 is a flexible substrate on which a predetermined circuit is formed, 20 is a stator coil, and six stator coils 20 are provided in this embodiment. Here, the flexible substrate 19 is provided on the bottom surface of the stator yoke 17. The stator coil 20 is adhered, and the stator coil 20 is fixed to the bottom surface of the stator yoke 17 in an annular shape, and is connected to each of the flexible substrates 19.

Reference numeral 22 is a bearing which is a bearing of the rotor shaft 9, 23 is an inner race retaining collar arranged between the bearings 22, and 24 is an output gear.

FIG. 3 is a side sectional view of the embodiment shown in FIG.
25 is a circular recess 25 formed on the bottom side of the carriage 1.
The stator yoke of the stator portion 21 is placed in the recess 25.
17 is housed so as to be flush with the bottom surface of the carriage 1.

The flexible substrate 19 adhered to the stator yoke 17 is also adhered to the bottom surface of the carriage 1, and one end of the flexible substrate 19 is wound around the upper surface of the carriage 1 and mounted on the carriage 1. The print head 3 is pressure-connected to the leaf-spring-shaped circuit terminal 33, whereby drive control of each dot pin (not shown) of the print head 1 is performed.

Further, a rotor stay 18 is inserted into the hole of the stator yoke 17 from the upper surface side of the carriage 1 and fixed by screwing, and the rotor portion 16 has a rotor magnet 15
The rotor shaft 9 is inserted into the rotor stay 18 so as to face the stator coil 20 of the stator portion 21 with a predetermined gap (0.5 mm in this embodiment), and is rotatably supported via a bearing 22. In addition, an output gear 24 located on the front side of the carriage 1 is attached to the upper portion of the rotor shaft 9.

In this way, by assembling the rotor portion 16 and the stator portion 21, a flat DC brushless motor having a thickness of about 30 mm is constructed, and the flat DC brushless motor is just accommodated in the bottom of the carriage 1. The pinion 11, which is mounted in the form and is fixed to the rotor shaft 9, is meshed with the rack 7.

Therefore, when the pinion 11 rotates together with the rotor shaft 9, a propulsive force acts between the pinion 11 and the rack 7, whereby the print head 3 and the ink ribbon cartridge 4 move in the horizontal direction together with the carriage 1.

Reference numeral 26 denotes a planetary gear meshed with an output gear 24 attached to the upper end of the rotor portion 16, 27 denotes a swingable arm attached to the rotor portion 16, and the planetary gear 26 is supported by the arm 27. Has been done.

28 is an idle gear corresponding to the planetary gear 26, 31 is a feed gear meshed with the idle gear 28, 32 is an output shaft to which the feed gear 31 is attached, and the output shaft 32 is provided in the ink ribbon cartridge 4. ing.

Each of these gears, along with the idle gears 29 and 30 described later,
It constitutes a power transmission mechanism for ribbon feed for feeding the ink ribbon 5, and is combined in a plane on the carriage 1.

Reference numeral 34 is a detector having a light emitting element and a light receiving element mounted on the flexible substrate 19 with the timing slit disk 12 interposed therebetween, 35 is a platen, and 36 is a printing paper.

FIG. 4 is a plan view of the embodiment shown in FIG. 1, in which the ink ribbon cartridge 4 is removed, and 37 is a clamp screw for fixing the print head 3 to the carriage 1 on both sides thereof.

FIG. 5 is a plan view showing the power transmission mechanism for feeding the ribbon. As shown in FIG. 5, an idle gear 29 is provided at a position opposite to the idle gear 28 with the planet gear 26 interposed therebetween. The idle gear 30 always meshes with the gear 29 and the feed gear 31.

Further, the arm 27 supporting the planetary gear 26 is adapted to swing around the rotor portion 16 about its axis, whereby the planetary gear 26 meshes with one of the idle gears 28, 29. It is like this.

The operation of the power transmission mechanism for feeding the ribbon is as follows.

First, when the rotor shaft 9 rotates counterclockwise, the planetary gear 26 meshing with the output gear 24 rotating in the same direction as the rotor shaft 9 rotates clockwise, which causes the arm 27 to rotate counterclockwise. The planetary gear 26 meshes with the idle gear 28 by rocking.

Therefore, the idle gear 28 receives the rotational force of the planet gear 26 and rotates counterclockwise, and the feed gear 31 meshing with the idle gear 28 rotates clockwise together with the output shaft 32.

Next, when the rotor shaft 9 rotates clockwise, the planetary gear 26 meshing with the output gear 24 that rotates in the same direction as the rotor shaft 9 rotates counterclockwise, which causes the arm 27 to rotate clockwise. The planetary gear 26 swings and meshes with the idle gear 29.

Therefore, the idle gear 29 receives the rotational force of the planetary gear 26 and rotates clockwise, and the idle gear 30 meshing with the idle gear 29 rotates counterclockwise and meshes with the idle gear 30. The feed gear 31 rotates clockwise together with the output shaft 32.

In this way, the output shaft 32 always rotates in the same direction together with the feed gear 31, because the rotation of the output shaft 32 causes the feeding direction of the ink ribbon 5 to always be the same direction.
Since the moving direction of the carriage 1 during printing is changed, even if the rotation direction of the rotor shaft 9 changes, the ink ribbon 5
The feed direction of is configured so as not to change.

Next, the overall operation of this embodiment will be described mainly with reference to FIG.

First, a flexible board using the flexible cord 8
When a predetermined current is applied to the stator coil 20 from 19, the rotor portion 16 is rotated by the action of the stator coil 20, and the rotation angle of the rotor portion 16 is detected by the detector 34 that sandwiches the slit 13 of the timing slit disk 12. It

As the rotor portion 16 rotates, the pinion 11 attached to the rotor shaft 9 rotates, and the pinion 11 generates propulsive force by meshing with the rack 7 as described above. Then, horizontally move along the guide rail 6 and the rack 7.

Further, the output gear 24 is also rotated by the rotation of the rotor shaft 9, and the rotational force thereof finally rotates the output shaft 32 for running the ink ribbon 5 in a fixed direction as described above. The print head 3 travels in the same direction so as to cross the front end surface thereof.

Then, the print command to the print head 3 is transmitted to the print head 3 from the circuit terminal which is pressure-contacted with one end of the flexible substrate 19, and the print is performed on the print paper 36 via the ink ribbon 5 by the print pin. .

[Effect of the Invention] As described above, according to the present invention, the rotor shaft integrated with the flat rotor magnet in which the N poles and the S poles are alternately magnetized in the axial direction is formed by horizontal movement of the carriage. One end of the carriage is rotatably attached to the carriage so as to be substantially orthogonal to the carriage, and a stator coil annularly arranged around the rotor shaft so as to face the rotor magnet is fixed to the carriage. By configuring a flat DC brushless motor mounted on the lower surface of the, and by attaching a pinion to the lower portion of the rotor shaft, by providing a rack that meshes with the pinion in parallel with the guide rail that guides the movement of the carriage, Since the driving force of the flat DC brushless motor directly acts on the carriage, it has a toothed shape as in the past. The power loss due to the interposition of the belt, the wire rope, the screw shaft and the like is eliminated, and at the same time, the inclusions do not extend or deform, so that the accuracy of moving and positioning the print head can be improved.

Further, according to the present invention, an output gear is attached to the upper portion of the rotor shaft, and a ribbon feed power transmission mechanism that meshes with the output gear and transmits the rotational force to the ink ribbon of the ribbon cartridge is provided on the carriage. Since the ribbon feed power transmission mechanism is used to drive the ink ribbon, the ribbon feed power transmission mechanism can have a simple structure including a plurality of gears. Therefore, it is easy to assemble.

[Brief description of drawings]

FIG. 1 is a perspective view of an essential part showing an embodiment of a serial printer according to the present invention, FIG. 2 is an exploded perspective view of a flat DC brushless motor used in the embodiment of FIG. 1, and FIG. 3 is FIG. 4 is a plan view of the embodiment shown in FIG. 1, and FIG. 5 is a plan view showing a ribbon feed power transmission system used in the embodiment shown in FIG. 1 ... Carriage 3 ... Print head 4 ... Ribbon cartridge 5 ... Ink ribbon 6 ... Guide rail 7 ... Rack 9 ... Rotor shaft 11 ... Pinion 14 ... Rotor yoke 15 ... Rotor magnet 16 ... Rotor Part 17 …… stator yoke 18 …… rotor stay 19 …… flexible substrate 20 …… stator coil 21 …… stator part 24 …… output gear 26 …… planetary gear 27 …… arm 28 to 30 …… idle gear 31 …… Feed gear 32 …… Output shaft

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Takashi Itaya 1-7-12 Toranomon, Minato-ku, Tokyo Oki Electric Industry Co., Ltd. (56) Reference JP-A-57-202866 (JP, A) 57-195381 (JP, U) Actual development Sho 57-133293 (JP, U)

Claims (1)

[Claims] 1. A serial printer in which a carriage having a print head and a ribbon cartridge having an ink ribbon running on a front end surface of the print head is horizontally moved, and N poles and S poles are alternately magnetized in an axial direction. A rotor shaft integrated with the flat rotor magnet is rotatably attached to the carriage at one end thereof so as to be substantially orthogonal to a horizontal plane formed by horizontal movement of the carriage, and the rotor shaft is opposed to the rotor magnet. A flat DC brushless motor mounted on the lower surface of the carriage is configured by fixing a stator coil annularly arranged around the axis of the carriage to the carriage, and a pinion is attached to a lower portion of the rotor shaft to form the pinion. Align the rack that meshes with the guide rail that guides the movement of the carriage. An output gear is attached to the upper portion of the rotor shaft, and a ribbon feed power transmission mechanism that meshes with the output gear and transmits the rotational force to the ink ribbon of the ribbon cartridge is provided on the carriage. Characteristic serial printer.