JPH0734687Y2 - Carriage drive mechanism of printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a drive mechanism for a carriage having a printer head in a printer apparatus.

[Prior Art] As a conventional carriage drive mechanism of this type of printer device, there is, for example, the one described in Japanese Utility Model Laid-Open No. 61-78639.

In this product, an endless belt having pins whose ends project from both sides in the width direction is spanned between a pair of pulleys arranged at predetermined positions, and both ends of the pins are in a direction substantially perpendicular to the paper feeding direction. It engages with a guide groove provided in the carriage that reciprocates. The guide groove extends in the paper feeding direction, and allows the pin to move from when the pin reaches the pulley to when it exits the pulley. Further, since the carriage has to move to the outside of the pulley, the lower surface of the carriage is provided with a notch for passing the shaft of the pulley.

[Problems to be Solved by the Invention] However, in such a conventional carriage drive mechanism of a printer device, as shown in FIG. Both ends of the pin 2 protruding from the upper surface plate 3a and the lower surface plate 3b of the carriage 3
Since it was structured to engage with the guide grooves 4 and 5 provided on the
Although it is possible to prevent the pin 2 from collapsing with respect to the belt body, since the notch for passing the shaft of the pulley is provided in the carriage, the rigidity in the central portion of the carriage is significantly weakened, and the carriage does not have a printing pressure. Therefore, there is a problem in that it vibrates or is elastically deformed, and adverse effects such as print misalignment occur.

Therefore, focusing on the above-mentioned problems, if the thickness of the central portion of the carriage is increased to increase its rigidity, adverse effects such as print misalignment can be eliminated, but the entire carriage becomes thicker and can be made smaller and lighter. The new problem of disappearing arises.

Further, in the conventional carriage 3 whose main part is shown in FIG. 7, the guide groove 5 provided in the lower surface plate 3b is cut by the notch 6 and is discontinuous, so that the pin 2 is removed from one guide groove. When moving to the other guide groove, interference with the notch 6 may occur, and there is also a problem that malfunction of the carriage drive tends to occur.

The present invention has been made in view of such conventional problems, and prevents twisting of the belt main body by aligning the axis of the pin fixed to the endless belt with the pitch line of the belt main body. An object of the present invention is to solve the above-mentioned problems by projecting one of the pins fixed to the belt for a long time and engaging the projecting portion with the guide groove to prevent the pin from falling.

[Means for Solving Problems] In order to achieve the above object, the present invention has a guide groove of a carriage in which a pin is fixed to an endless belt that rotates in one direction, and the pin is movably supported on a guide rail. In a carriage drive mechanism of a printer device that reciprocates the carriage along a guide rail by the driving force of the pin, the pin includes first and second pin split pieces that sandwich the belt body from both sides. The divided piece is composed of a first ring and a second ring that are respectively fitted to the ends protruding from both sides of the belt main body while sandwiching the belt main body, and the axis of the pin corresponds to the pitch line of the belt main body. By matching the belt body, twisting of the belt main body is prevented, only one protrusion is engaged with the guide groove, and the length of the protrusion is engaged with the guide groove so that the pin falls down. The feature is that the length is set to prevent

[Operation] Therefore, in the present invention, the pin is fixed to the endless belt by aligning the axial center of the pin with the pitch line of the belt body, and only one protruding portion of the pin is engaged with the guide groove of the carriage. Since the pin is prevented from collapsing by engaging with the guide groove, the belt main body can be prevented from being twisted and the carriage can be surely reciprocated, and the rigidity of the carriage can be increased to improve the printability. Can be prevented.

[Embodiment] Next, an embodiment of the present invention will be described with reference to the drawings.

1 to 5 show an embodiment of the present invention.
FIG. 1 is an overall perspective view applied to a carriage driving mechanism of a serial dot printer, FIG. 2 is a sectional view of a main part of FIG. 1, FIG. 3 is a plan view showing an example of an endless belt, and FIG. The same is a perspective view, and the fifth is an exploded perspective view.

First, the structure will be described. 10 shown in FIGS. 1 and 2 is an endless belt, which is composed of an endless belt body 11 and a pin 12 fixed to the belt body 11.
Both ends of the pin 12 project on both sides in the width direction of the pin. The belt main body 11 has a large number of teeth 13 having a trapezoidal cross section in the longitudinal direction inside thereof at equal intervals, and a pin 12 is fixed to the belt main body 11 in association with one of the teeth 13. There is.

As shown in FIGS. 3 to 5, the pin 12 includes first and second pin split pieces 14 and 15 that sandwich the belt main body 11 from both sides, and both pin split pieces 14 and 15 when the belt main body 11 is sandwiched. 15
The first and second rings 16 and 17 are externally fitted to the ends protruding from both sides of the belt body 11.

The first and second pin division pieces 14 and 15 have semi-cylindrical large diameter portions 14a and 15a, and small diameter portions 14b, 14c and 15b and 15c that are continuous on both sides thereof and are also semi-cylindrical. The one small-diameter portion 14b, 15b is set to have a length significantly longer than the other small-diameter portion 14c, 15c. A groove having a thickness from the pitch line L of the belt body 11 to the inner surface of the belt and a depth and width corresponding to the width of the belt body 11 is formed on the plane side of the large diameter portion 14a of the first pin division piece 14. 14d and a recess 14e having the same shape and size as the tooth 13 formed in the center of the groove 14d.
And are provided.

Also, on the plane side of the large diameter portion 15a of the second pin division piece 15,
A groove having a thickness from the pitch line L of the belt body 11 to the outer surface of the belt and a depth and width corresponding to the width of the belt body 11.
15d is provided. A ring 16 having a length corresponding to the length is externally fitted to one of the small-diameter portions 14b, 15b of the pin split pieces 14, 15 having a large protrusion amount, and the one protrusion portion having a large protrusion amount. 12a is formed and the other small diameter portion 1 with a small amount of protrusion
4c and 15c have a ring 17 with a length commensurate with the length.
Is externally fitted to form the other protruding portion 12b having a small protruding amount.

Thus, in the assembling of the endless belt 10, one of the teeth 13 of the belt body 11 is provided with the recess 14e in the groove 14d provided on the plane side of the large diameter portion 14a of the first pin division piece 14. Engaging and second
The groove 15d provided on the plane side of the large diameter portion 15a of the pin split piece 15 is engaged. Then, the rings 16 and 17 are externally fitted to the cylindrical protrusions 12a and 12b formed at both ends of the pin divided pieces 14 and 15, respectively,
This endless belt 10 can be obtained by fastening both with caulking.
Assembly of is completed.

Further, reference numeral 18 shown in FIG.
Is a driven-side timing pulley, and the endless belt 10 is stretched between both timing pulleys 18 and 19 which are arranged in parallel with each other with a predetermined interval. Each timing pulley 1
Semicircular pin receiving grooves 18a and 19a for allowing engagement with the pin 12 are provided at predetermined positions on the outer circumferences of 8 and 19 in consideration of the engagement timing. Such timing pulley 1
8 and 19 are rotatably supported by a printer body (not shown), and the driving force of a motor 21 can be transmitted to a driving side timing pulley 18 via a reduction gear mechanism 20.

The reduction gear mechanism 20 individually meshes with the pulley-side gear 20a fixed to the rotation shaft of the timing pulley 18, the motor-side gear 20b fixed to the rotation shaft of the motor 21, and both gears 20a and 20b, and is integrated with each other. It is composed of two intermediate gears 20c and 20d. The motor side gear 20b is provided with a timing disc 23 having a plurality of slits 22 around the rotation axis of the motor 21, and the timing disc 23 is provided with a photosensor 24 facing the timing disc 23. The disk 23 and the photo sensor 24 form a print timing detector of the printer head 32.

Reference numeral 25 denotes a rectangular parallelepiped carriage, and a belt groove 26 that opens downward and is continuous in the width direction is provided below the midway portion of the carriage in the longitudinal direction. Further, the carriage 25 has a through hole which is parallel to the belt groove 26 and penetrates in the width direction.
27 and a support groove 28 that is open in the longitudinal direction and is continuous in the width direction are provided. A first guide rail 29, both ends of which are supported by the printer body, is slidably inserted into the through hole 27 of the carriage 25, and a support groove 28 is formed by a first guide rail 29, both ends of which are also supported by the printer body. The first and second carriages 25 are slidably engaged with the second guide rail 30 and the carriage 25 is arranged in parallel so as to sandwich the endless belt 10 in this way.
It is slidably supported by the guide rails 29, 30 of.

Further, at a midway portion in the longitudinal direction of the carriage 25, the lower end thereof is vertically penetrated through the carriage 25 in the longitudinal direction so that the lower end thereof is opened in the belt groove 26 and intersects with the endless belt 10 arranged in the belt groove 26. An extending guide groove 31 is provided. In this guide groove 31, the longer protrusion 12 of the pin 12 provided on the endless belt 10 is
The carriage 25 is guided by the two guide rails 29 and 30 by the driving force of the pin 12 to move in the axial direction thereof, and the protrusion 12a moves in the longitudinal direction along the guide groove 31. To do.

The depth of the guide groove 31, that is, the wall thickness of the carriage 25 in the longitudinal direction is determined by the pin 12 that engages with this when the belt is driven.
Set the length so that it can be prevented from falling.

32 is a serial printer head mounted on the upper surface of the carriage 25, 33 is a color ribbon of two colors facing the front surface, 34 is a platen disposed on the front surface of the printer head 32, and on this platen 34 The printer head 32 prints two colors on the supplied paper 35 via the color ribbon 33.

Next, the operation of this embodiment will be described.

The rotational force of the motor 21 is transmitted to the drive-side timing pulley 18 via the reduction gear mechanism 20, and the rotational force is transmitted to the endless belt 10.
When traveling in the direction of arrow Y, the carriage 25 whose pin 12 engages with the guide groove 31 moves in the same direction as the pin 12 due to the driving force of the pin 12 provided on the endless belt 10.

At this time, the longer protrusion 12a of the pin 12 is engaged with the guide groove 31, and the engagement length between the protrusion 12a and the guide groove 31 is made sufficiently long to prevent the pin 12 from collapsing. Therefore, the driving force of the belt is rigidly transmitted to the carriage 25 via the pin,
Therefore, the carriage 25 can be driven in synchronization with the movement of the endless belt 10 without causing a delay. Also,
The rigidity of the carriage 25 in the longitudinal direction, that is, the guide groove 31
As for the rigidity of the portion provided with, since the thickness of the portion is sufficiently thickened to increase the rigidity, it is possible to suppress the vibration and elastic deformation of the carriage 25 due to the printing pressure during printing. It is possible to prevent the dot pitch from being disturbed by the printing operation of the head 32, and to print a neat font on the paper 35 without any print distortion.

[Effect of the Invention] As described above, according to the present invention, the shaft center of the pin is aligned with the pitch line of the belt body, and one of the protrusions of the pin is set to be long and engaged with the guide groove. Since the pin does not fall down at times, the twisting of the belt body can be prevented, the driving force of the pin can be reliably transmitted to the carriage, and the rigidity of the carriage can be ensured to be large. Therefore, it is possible to effectively suppress the vibration and elastic deformation of the carriage due to the printing pressure at the time of printing, thus preventing the dot pitch from being disturbed by the printing work of the printer head, and creating a beautiful typeface with no print misalignment. The effect of being able to print is obtained. In addition, in the conventional carriage, the defective operation of the pin was apt to occur due to the presence of the notch intersecting with the guide groove. However, in the present invention, the guide groove is the only groove in which the pin engages. The effect of not causing a malfunction is also obtained.

[Brief description of drawings]

1 to 5 show an embodiment of the present invention. FIG. 1 is an overall perspective view applied to a carriage driving mechanism of a serial dot printer, and FIG. 2 is a sectional view of a main part of FIG. ,
FIG. 3 is a plan view showing an example of an endless belt, FIG. 4 is the same perspective view, FIG. 5 is the same exploded perspective view, and FIG. 6 is a sectional view showing a main part of a conventional carriage drive mechanism. The figure is also a bottom view showing a main part of a conventional carriage. 10: Endless belt, 12: Pin 12a: Projection, 14, 15: Pin division piece 16, 17: Ring, 25: Carriage 26: Belt groove, 31: Guide groove

Claims (1)

[Scope of utility model registration request] 1. A pin is fixed to an endless belt rotating in one direction, the pin is engaged with a guide groove of a carriage movably supported on the guide rail, and the carriage is guided to the guide rail by a driving force of the pin. In a carriage drive mechanism of a printer device that reciprocates along the pins, the pins are divided into first and second pin split pieces that sandwich the belt body from both sides, and from both sides of the belt body while the split pieces sandwich the belt body. It consists of a first ring and a second ring that are fitted onto the protruding ends, respectively, and the twisting of the belt main body is prevented by matching the axis of the pin with the pitch line of the belt main body. Only the portion is engaged with the guide groove, and the length of the protruding portion is set to a length capable of preventing the pin from falling down by engaging with the guide groove. Of the carriage driving mechanism.