JPH11348324A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printer capable of accurately positioning the part engaged with the drive transmission part of the printer in a predetermined head and capable of uniformly and efficiently transmitting printing drive force to a printing lever. SOLUTION: A printer has a drive part 21 having the push-out rod 30 driven by a solenoid 23 and constituted so as to move by the engagement with the drive transmission part of the printer by an engaging pin 31. First and second carriage parts 41, 51 are separately constituted and the first carriage part 41 having a printing lever 45 guided by a main guide shaft 10 is fixed to the front side part 22b of the yoke 22 of the solenoid 22. The second carriage part 51 guided by a follower guide shaft 11 is fixed to the upper surface part 22a of the yoke 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a printer having a dot impact type print head.

[0002]

2. Description of the Related Art Conventionally, as a small dot impact type printer, a print head for printing on recording paper is periodically reciprocated by driving a groove cam or the like along a guide shaft provided in the printer body. So-called shuttle printers configured to move have been proposed. As such a print head, for example, a print head 100 as shown in FIG.
0 is a drive unit 150 having an electromagnetic solenoid 152;
It has a carriage section 160 made of resin and integrally formed in a substantially L-shaped cross section.

[0003] The driving portion 150 has an engaging pin 151 which engages with a groove cam of a printer (not shown) on a rear portion thereof.
The push rod 152a is configured to be pushed out from the front side by driving the electromagnetic solenoid 152.

[0004] Here, the carriage section 160 includes the driving section 1.
Guide holes 161 and 162 for penetrating the main guide shaft 102 and the sub guide shaft 103 arranged in parallel with the printer are formed in the upper part of the printer 50. Further, a plurality of print levers 163 are arranged on the front side of the carriage unit 160 at regular intervals in the width direction of the recording paper.

In this case, the carriage 160 of the print head 100 is fixed to the front side 153b of the yoke 153 using a plurality of screws 180.

Each print lever 1 of the carriage unit 160
63 is a support shaft 1 extending in the longitudinal direction of the carriage unit 160
64, and is configured to be pushed out in the direction of arrow A against the elastic force of the torsion coil spring 165 by the pushing action of the pushing rod 152a of the drive unit 150.

FIG. 6 shows a print head according to another conventional example.

[0008] As shown in FIG.
Has the same basic configuration as the print head 100 shown in FIG. 5, but in the case of this conventional example, the carriage 260 is
The yoke 153 of the drive unit 150 is fixed on the upper surface side 153 a of the yoke 153 using a plurality of screws 280.

[0009]

However, such a conventional print head has the following problems.

That is, the front side 153 of the yoke 153
b, the print head 100 having the carriage 160 fixed thereto
In the case of, the printing driving force of the electromagnetic solenoid 152 can be efficiently transmitted to the printing lever 163, but it is difficult to secure the accuracy in bending the yoke 153. The engagement pin 151 fixed to the portion cannot be accurately positioned, and as a result, there is a problem that locking or the like is likely to occur due to poor engagement between the engagement pin 151 and the groove cam of the printer.

On the other hand, in the case of the print head 200 in which the carriage portion 260 is fixed to the upper surface side portion 153a of the yoke 153, the positioning of the engagement pin 151 is accurate, but the bending accuracy of the yoke 153 described above is poor. The printing lever 163 and the pushing rod 152a are easily separated from each other due to insufficient rigidity of the integrally formed resin carriage 260 (gap g shown in FIG. 6).
The stroke of the print lever 163 varies.
There is a problem in that the force of the printing becomes weaker, and shading tends to occur during printing.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and enables accurate positioning of a portion of a print head which engages with a drive transmission portion of a printer, and a print lever. It is an object of the present invention to provide a printer capable of transmitting a printing driving force uniformly and efficiently to a printer.

[0013]

According to a first aspect of the present invention, there is provided a printer having an extruding rod driven by an electromagnetic solenoid, wherein an extruding rod is provided at a drive transmitting portion and an engaging portion of the printer. A drive unit configured to be movable in a predetermined direction by combining the drive unit and a print lever pushed out by the push-out rod, and configured to be movable along a first guide member of the printer. A first carriage portion fixed to the mounting member, and configured to be movable along a second guide member that is provided separately from the first carriage portion and that is substantially parallel to the first guide member; A print head having a second carriage section fixed to a mounting member of the drive section.

In the case of the first aspect of the present invention, the first carriage and the second carriage are formed separately and fixed to the mounting member of the driving unit.
Even if the processing accuracy of the mounting member is somewhat poor, the position of the first carriage unit with respect to the drive unit does not shift, and the proper positional relationship between the push rod driven by the electromagnetic solenoid and the print lever is determined. Since it can be stably maintained, it is possible to transmit a uniform and efficient print driving force from the push rod to the print lever.

On the other hand, since the second carriage portion guided along the second guide member and the drive portion of the print head are fixed, the drive portion is engaged with the second guide member. The engagement portion can be accurately positioned, thereby preventing locking due to poor engagement between the engagement portion of the drive unit and the drive transmission means of the printer.

In this case, as in the second aspect of the present invention,
In the first aspect of the invention, it is also effective that the second carriage section is configured to slide with the second guide member in the vicinity of the engagement section of the drive section.

According to the second aspect of the present invention, since the portion of the second carriage portion that is slid and guided by the second guide member is close to the engagement portion of the drive portion, the processing accuracy of the mounting member is improved. It is possible to minimize the displacement of the engagement portion due to the variation in the above, and it is possible to more reliably maintain the appropriate positional relationship between the first and second guide members and the engagement portion of the drive unit. .

According to a third aspect of the present invention, as in the third aspect of the present invention, the first carriage portion is
At least two sliding portions that slide with the member of the first guide
It is also effective that the second carriage section has one sliding section that slides with the second guide member.

According to the third aspect of the present invention, since the second carriage has only one portion that slides with the second guide member, the size of the second carriage is reduced. The weight can be reduced. In addition, since it becomes possible to expose a portion other than the portion occupied by the second carriage portion in the driving portion, it is possible to release heat from the electromagnetic solenoid in this portion to prevent a temperature rise.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a printer according to the present invention will be described below in detail with reference to the drawings.

FIG. 1 is an exploded perspective view showing the internal configuration of the printer according to the present embodiment.

As shown in FIG. 1, a DC motor 3 as a driving source of the printer 1 is provided on the back side of the main body frame 2 of the printer 1 of the present embodiment. , Groove cam (drive transmitting means) 4, cylindrical cam 5,
The worm 6 and the like are fixed.

A main guide shaft (first guide member) for guiding a print head 20, which will be described later, in the width direction (arrow A or B) of the recording paper is provided near the front side of the DC motor 3 of the main body frame 2. 10, a slave guide shaft (second guide member)
11 are arranged in parallel.

On the front side of the main body frame 2, a paper feed mechanism 60 for feeding recording paper facing the print surface 20a of the print head 20 is mounted. This paper feed mechanism 60
Is formed with an insertion opening 60a for inserting recording paper in the direction of arrow C in the front side portion. An engagement portion 61a of a bevel gear 61 rotatably provided at one end of the paper feed mechanism 60 is provided with an engagement pin 7a of a cam follower 7 which periodically swings with the rotation of the cylindrical cam 5. , The recording paper is intermittently fed in the direction of arrow D shown in the figure.

In the upper part of the paper feed mechanism 60,
An ink ribbon cassette (not shown) is attached. The ink ribbon cassette engages with an engagement pin 9a that rotates together with a gear 9 to which a driving force is transmitted from the worm 6 via a gear 8, so that the endless ink ribbon in the ink ribbon cassette is fed in a predetermined direction. It is configured.

FIG. 2 is a side view showing the internal configuration of the print head according to the present embodiment, FIG. 3 is a plan view showing the external configuration of the print head, and FIG. It is a front view which shows a structure.

As shown in FIGS. 2 to 4, the print head 20 according to the present embodiment has a front side carriage section 41 (first carriage section) and a rear side carriage section 51 (first carriage section) made of separate resins. 2) and a drive unit 21 having an electromagnetic solenoid 23. Here, the front side carriage unit 41 is disposed on the front side (the left side in FIG. 2) of the drive unit 21, and the rear side carriage unit 51.
Are disposed on the upper surface side (upper side in FIG. 2) of the drive unit 21.

As shown in FIG. 2 or FIG. 4, the front side carriage portion 41 has substantially the same length as the drive portion 21, and a support shaft 43 is provided so as to penetrate the longitudinal direction. A predetermined number of print levers 45 are swingably attached to the support shaft 43 at regular intervals, and each print lever 45 is
The torsion coil spring 44 is configured to be urged toward the drive unit 21 side.

As shown in FIG. 2, the front side carriage portion 41 is provided with a guide hole 42 near the upper side of the printing surface 20a, through which the main guide shaft 10 of the printer 1 penetrates. In the case of the present embodiment, as shown in FIG. 3, an oil supply port 41 b for supplying lubricating oil is formed on the upper surface of the front side carriage portion 41, whereby the front side carriage portion 41 has a longitudinal direction. The main guide shaft 10 slides at two sliding portions 41a formed at both ends.

As shown in FIG. 2 or FIG. 4, the drive section 21 is provided with the same number of electromagnetic solenoids 23 as the print levers 45 for driving the print levers 45. In this embodiment, a yoke (mounting member) 2 having a substantially U-shaped cross section is used.
A fixed iron core 24 made of a magnetic material is fixed inside 2, and a coil bobbin 26 around which a coil 25 is wound is fitted to the fixed iron core 24. Here, coil bobbin 2
6 is urged to the fixed iron core 24 by a spring member 27 provided on a coil pressing plate 28 on the back side of the print head 20.

The movable iron core 2 made of a magnetic material is located inside the coil bobbin 26 at a position close to the fixed iron core 24.
9 is slidably supported so as to penetrate the coil holding plate 28. The movable iron core 29 is provided with the support shaft 43 described above.
The extruding rod 30 extending in a direction perpendicular to the axis and penetrating through the fixed iron core 24 is fixed.
Is configured to be movable in the direction of arrow E or F together with the movable iron core 29.

Here, as shown in FIG. 2, the pushing rod 30 of each electromagnetic solenoid 23 is configured such that the tip end 30a contacts the print lever 45, and the coil 25
When a magnetic circuit is generated by energizing the print lever 45, the print lever 45 is pressed in the direction of arrow G against the urging force of the torsion coil spring 44 so that the front end 45a is
It protrudes from the first printing surface 20a.

As shown in FIG. 2 or FIG. 3, the driving portion 21 has a cylindrical engaging pin 31 attached to the coil holding plate 28.
Is provided. As shown in FIG.
Reference numeral 1 denotes a straight line extending in a direction orthogonal to the main guide shaft 10 and the slave guide shaft 11 and connecting the center of the main guide shaft 10 and the slave guide shaft 11 to a straight line L2 passing through the center of the engaging pin 31. It is configured to be parallel. And
The engagement pin 31 is provided so as to engage with a groove 4a formed in the groove cam 4 shown in FIG.

Here, as shown in FIG. 2 or FIG. 4, the front side carriage portion 41 is fixed to the front side portion 22b of the yoke 22 of the drive portion 21 using a predetermined number of screws 48. In the case of the present embodiment, each screw 48 is
5 and is fixed at a position close to the push rod 22.

As shown in FIG. 3, in this embodiment, the rear side carriage portion 51 is formed to be considerably shorter than the drive portion 21. Then, the rear side carriage unit 51
Is fixed to the upper surface side portion 22a of the yoke 22 of the drive section 21 by screws 58 in the vicinity of the engagement pin 31. With such a configuration, in the present embodiment,
The surface of the yoke upper side surface portion 22a is exposed.

As shown in FIG. 2, the rear carriage 5
1 is provided with a guide hole 52 having a long hole shape, and the guide hole 52 is configured such that the slave guide shaft 11 of the printer 1 passes therethrough. In this case, in the rear side carriage portion 51, one of the sliding portions 51a slides with the driven guide shaft 11.

As described above, according to the present embodiment,
Since the front side carriage portion 41 and the rear side carriage portion 51 are formed separately and fixed to the yoke 22 of the drive portion 21, even if the bending accuracy of the yoke 22 is somewhat poor, The position of the front carriage unit 41 with respect to the drive unit 21 does not shift, and the appropriate positional relationship between the push rod 30 driven by the electromagnetic solenoid 23 and the print lever 45 can be stably maintained. As a result, according to the present embodiment, a uniform and efficient print driving force can be transmitted from the push rod 30 to the print lever 45, and printing without shading can be performed.

On the other hand, in the case of the present embodiment, the rear side carriage portion 51 guided along the slave guide shaft 52
And the drive unit 21 are fixed by the screw 58, so that the engaging pin 31 of the drive unit 21 can be accurately positioned with respect to the follower guide shaft 52. Locking due to poor engagement between the groove 31 and the groove cam 4 can be prevented.

Further, according to the present embodiment, since the sliding portion 51a of the rear side carriage portion 51 with the follower guide shaft 52 is close to the engaging pin 31 of the driving portion 21, the yoke 22
Position deviation of the engaging pin 31 due to variation in the bending accuracy of the main guide shaft 10 can be more reliably achieved.
In addition, it is possible to maintain an appropriate positional relationship between the slave guide shaft 11 and the engagement pin 31 of the drive unit 21.

Further, in the case of the present embodiment, the rear carriage portion 51 can be made smaller to reduce its weight.
Since the surface of 2a can be exposed, heat from the electromagnetic solenoid 23 can be released to prevent a rise in temperature. Note that the present invention is not limited to the above-described embodiment, and the shapes and positional relationships of the first and second carriages and the engagement portion with the drive transmission unit of the printer are out of the scope of the invention. Unless otherwise stated, various changes can be made.

[0041]

As described above, according to the present invention, it is possible to accurately position the portion of the print head which engages with the drive transmission portion of the printer, regardless of the processing accuracy of the parts, and to position the print lever with respect to the print lever. The printing driving force can be transmitted uniformly and efficiently, and thereby the printing quality can be improved.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an internal configuration of a printer according to an embodiment of the present invention.

FIG. 2 is a side view showing the internal configuration of the print head according to the embodiment.

FIG. 3 is a plan view showing an external configuration of the print head.

FIG. 4 is a front view showing an external configuration of the print head.

FIG. 5 is a side view showing the internal configuration of a conventional print head.

FIG. 6 is a side view showing the internal configuration of another conventional print head.

[Explanation of symbols]

 Reference Signs List 4 groove cam (drive transmission means) 10 main guide shaft (first guide member) 11 slave guide shaft (second guide member) 20 print head 21 drive unit 22 yoke (mounting member) 23 electromagnetic solenoid 30 push rod 31 Mating pin (engaging part) 41 Front side carriage part (first carriage part) 41a Sliding part 45 Print lever 51 Rear side carriage part (second carriage part) 51a Sliding part

Claims (3)

[Claims] A drive unit having an extruding rod driven by an electromagnetic solenoid, the driving unit being configured to be movable in a predetermined direction by being engaged with a drive transmitting unit of the printer at an engaging unit; A first carriage section fixed to an attachment member of the drive section, the first carriage section having a print lever pushed out by the first carriage section and being movable along a first guide member of the printer; A print head having a second carriage section fixed to a mounting member of the drive section, the print head being configured to be movable along a second guide member substantially parallel to the first guide member and being provided by a body. A printer comprising: 2. The printer according to claim 1, wherein said second carriage section is configured to slide with said second guide member near an engagement section of said drive section. . 3. The first carriage section has at least two sliding sections that slide on the member of the first guide, and the second carriage section slides on the second guide member. 3. The printer according to claim 2, wherein the printer is configured to have one sliding portion that slides.