JP3008570B2 - Print head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a print head for an impact type dot printer, and more particularly to a print head having a rhombus, ellipse, or parallelogram opposed to a printing paper. The present invention relates to a print head in which electromagnet mechanisms to be driven are arranged circumferentially.

[0002]

2. Description of the Related Art Conventionally, a print head of an impact type printer is roughly classified into a clapper type in which the attraction force of an electromagnet acts as a printing operation force, and a print head for canceling the attraction force of a permanent magnet by reverse excitation of the electromagnet. There is a spring charge type in which the distortion energy of a member acts as a printing operation force. Of these print heads, the clapper type is widely used because it can be manufactured at low cost.

FIG. 8 is a front view of a main part of a conventional clapper type print head. Reference numeral 21 denotes a print wire driven by an electromagnet (not shown). In this conventional example, the tips of the print wires 21 are arranged in a staggered manner. However, in this arrangement, when printing a vertical line, there are many electromagnets that are simultaneously driven, so that the peak of the drive current of the print head becomes large. Had.

FIG. 9 is a front view of a main part of a second conventional print head, and 22 is a print wire. In this conventional example,
The printing wires 22 are arranged in a diamond shape facing the printing paper. The 24 print wires 22 are divided into two groups of 12 wires. In each group, two print wires 22 at the center, two wires adjacent to both ends, and two print wires 22 at symmetrical positions are provided. The print head is divided into sets, and each set is disposed at the same position with respect to the running direction of the print head. Adjacent sets in each group are arranged at a distance of 1/6 times the pitch of the dots to be printed, and each set at the left end of the two groups is separated by a distance of twice and 1/12 times the dot pitch. I have. Thus, the printing wire 2
By arranging the two, a certain set is not driven simultaneously with a set adjacent thereto, and furthermore, a set in an opposing relationship among the two groups is not driven simultaneously, so that magnetic interference is reduced and the printing wire 21 is provided. Printing noise and driving power when striking a platen (not shown in the figure) can be greatly reduced.

FIG. 10A is a plan view of a second conventional print head. Reference numerals 23 and 24 denote electromagnets for driving a print wire 22. In the figure, the electromagnet 23 which is blank generates a magnetic force in a forward direction, and the electromagnets 24 arranged in oblique lines generate a magnetic force in a reverse direction. These two types of electromagnets are alternately arranged. With this arrangement, magnetic interference between the electromagnets 23 and 24 can be reduced.

FIG. 10B is a plan view of a print head according to a third conventional example, in which print wires (omitted in the drawing) are arranged in the same manner as in the second conventional example, and a positive magnetic force is applied. And two electromagnets 24 that generate magnetic forces in opposite directions are alternately arranged.

FIG. 10 (c) is a plan view of a print head according to a fourth conventional example, in which print wires (omitted in the drawing) are arranged in the same manner as in the second conventional example, and all of them are in the positive direction. It is driven by an electromagnet 23 that generates a magnetic force.

[0008]

However, in the above-mentioned conventional configuration, when the magnetic force directions of the electromagnets are all the same as in the fourth conventional example, a vertical line or a set of central portions in a print pattern including a vertical line is used. Since the distance between the electromagnets driven simultaneously in the pair adjacent thereto and the electromagnets is small, magnetic interference occurs, and FIG.
As shown in FIG. 11C or FIG. 11D, there is a problem that printing unevenness occurs. Further, in the second conventional example, the printing pressure is reduced as a whole as shown in FIG. 11A, and in the third conventional example, printing unevenness occurs alternately as shown in FIG. There was a problem that it decreased.

[0009]

SUMMARY OF THE INVENTION The present invention comprises a plurality of printing wires arranged in a rhombus, ellipse or parallelogram shape facing a printing paper, and a plurality of electromagnet mechanisms. A first group that generates a magnetic force in a first direction during operation, and a second group that generates a time force in a direction opposite to the first direction adjacent to each other.

[0010]

According to the above configuration, even when the electromagnets adjacent in the vertical direction are simultaneously driven, the magnetic force directions are different, so that printing unevenness due to magnetic interference can be suppressed.

[0011]

FIG. 3 is a sectional view of a main part of a print head according to an embodiment of the present invention. Reference numeral 1 denotes an armature that rotates about a fulcrum 1a, 2 denotes a yoke, 3 denotes an armature 1 and a fulcrum 1;
A spring for urging a, 4 is an electromagnet, 4a is a winding start end of the electromagnet 4, and 4b is a winding end end of the electromagnet 4.

FIG. 4 is a top view of the print head according to the present embodiment. A plurality of electromagnet mechanisms 5 including an armature 1, a yoke 2, a spring 3, and an electromagnet 4 are provided in a circumferential shape.

In the print head of this embodiment, the armature 1 is attracted and rotated by energizing the electromagnet 4.

FIG. 2 is a front view of a main part of the print head according to the present embodiment, which shows 12A1 to 12A12 and 12B1 to 12B1.
Reference numeral 2 denotes a printing wire to which the electromagnet mechanism 5 is connected. 24 print wires 12A1 to 12A12 and 12
B1 to 12B12 are divided into twelve sets. That is, the set obtained by 12A1 and 12A12 (hereinafter referred to as the first set)
Set), 12A2 and 12A11 (hereinafter, second set), similarly, 12A3 and 12A10 (hereinafter, third set), 12A4 and 1
2A9 (fourth set), 12A5 and 12A8 (fifth set)
Pairs), 12A6 and 12A7 (hereinafter referred to as sixth set), 12B1 and 12B12 (hereinafter referred to as seventh set), 12B2 and 12B11 (hereinafter referred to as eighth set), 12B3 and 12B10 (hereinafter referred to as ninth set), 1
2B4 and 12B9 (tenth set), 12B5 and 12B
8 (hereinafter the eleventh set), 12B6 and 12B7 (hereinafter the twelfth set).
Group). Then, the print heads of the first set and the second set are
The distance Q in the scanning direction of the dot is 1/6 times the dot pitch P.
ing. Therefore, in the first to sixth groups,
Sets adjacent to each other in the scanning direction in the seventh to twelfth groups
The interval Q between them is P / 6.

FIG. 1 is a sectional view of a main part of a print head according to the present embodiment. Numeral 10 denotes an electromagnet that generates a magnetic force in the forward direction of the electromagnet 4, and 11 generates a magnetic force in the reverse direction of the electromagnet 4.
It is an electric magnet. In the present embodiment, with a straight line that is parallel to the running direction of the print head and passes through the center of the print head as a boundary line, 12 electromagnets 10 are on the upper side and 1 electromagnet 11 is on the lower side.
Two are arranged. The direction in which the magnetic force is generated can be changed by changing the direction of the current applied to the electromagnet 4 or the winding direction of the electromagnet 4. Printing of the present embodiment configured as described above
The operation of the head will be described. Vertical line with print head
When printing, the print head moves to the left in FIG.
Move, it is connected to the print wires 12A6 and 12A7.
The electromagnet mechanism 5 is energized, and the printing wire 12A6 and
12A7 protrudes from the tip of the print head and prints two dots.
Print. At this time, the power connected to the printing wire 12A6
The magnet mechanism 5 was connected to the print wire 12A7 in the forward direction.
The electromagnet mechanism 5 generates a magnetic force in the opposite direction. Then print
When the head moves 2 / 12P, the printing wire 12A5
And the electromagnet mechanism 5 connected to 12A8,
Characters 12A5 and 12A8 project from the end of the print head.
And print one dot above and below the two dots already printed.
Print two dots. Printing is performed one after another in this way.
From the printing wire 12A1 to the printing wire 12A12
Twelve dots are printed. After that, the print head (2
+1/12) At the point of P movement, the printing wires 12B1 and
Power is supplied to the electromagnet mechanism 5 connected to the
Characters 12B1 and 12B12 from the end of the print head
Protrude and print two dots. Printing wire 12B1
Is printed by the printing wire 12A1 and the printing wire 12A2.
Between the dots and the printing wire 12B12 is the printing wire
Each dot is printed below the dot printed by 12A12
Print. Then, printing is performed one after another, and 24 dots are printed.
Print in columns. In this printing process, the printing wire 12
Through two electromagnet mechanisms 5 connected to A6 and 12A7.
When electromagnetized, the two electromagnet mechanisms 5 operate in opposite directions.
Since magnetic force is generated and adjacent to each other,
I am extinguished. This is the printing wire 12B6 and 12B
The same applies to the two electromagnet mechanisms 5 connected to 7.
You. Next, they were connected to the printing wires 12A5 and 12A8.
When two electromagnet mechanisms 5 are energized , two electromagnet machines
Structure 5 generates magnetic forces in opposite directions.
Although erased, the printing wires 12A6 and 12A7
Printing compared to the distance between two connected electromagnet mechanisms 5
Two electromagnets connected to wires 12A5 and 12A8
Since the distance between the mechanisms 5 is long, the influence is small. Therefore,
The dots printed by the print wires 12A5 and 12A8 are
From the dots printed by the printing wires 12A6 and 12A7
Prints darkly.

According to the present embodiment, the sixth set and the twelfth set are used.
As shown in FIG.
Since the direction of the magnetic force is reversed,
As shown, it is possible to reduce the variation in printing pressure due to magnetic interference .

In this embodiment, when a vertical line is printed as shown in FIG. 5, the printing pressure is slightly reduced only in the adjacent portions of the groups, although the range is acceptable. Therefore, the printing pressure can be increased and the printing pressure can be made uniform by making the energizing time applied to the electromagnet in the portion where the printing pressure has decreased longer than that of the others.

In this embodiment, the printing wires are arranged in a rhombus shape, but it is also possible to arrange the printing wires in a parallelogram shape as shown in FIG. In this case, as shown in FIG. 7, the printing wires 12A1 to 12A5 and 12B1 to 1
For 2B7, electromagnet 10, printing wire 12A6-1
Electromagnet 1 for 2A12 and 12B8-12B12
1 is connected.

[0019]

According to the present invention, a rhombus, which faces a printing paper,
A plurality of printing wires arranged in an elliptical or parallelogram shape and a plurality of electromagnet mechanisms, wherein the electromagnet mechanisms are adjacent to each other and generate a magnetic force in a first direction when activated.
And a second group that generates a time force in the direction opposite to the first direction adjacent to each other. Even if the electromagnets adjacent in the vertical direction are simultaneously driven, the magnetic force directions are different, Printing unevenness due to magnetic interference can be suppressed.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a print head according to an embodiment of the present invention.

FIG. 2 is a front view of the main part.

FIG. 3 is a sectional view of a main part of the same.

FIG. 4 is a front view of the same.

FIG. 5 is a plan view showing the printing result.

FIG. 6 is a front view of a main part of a print head according to another embodiment of the present invention.

FIG. 7 is a sectional view of the main part.

FIG. 8 is a front view of a main part of a conventional print head.

FIG. 9 is a front view of a main part of a second conventional print head.

10A is a cross-sectional view of a main part of a second conventional print head. FIG. 10B is a cross-sectional view of a main part of a third conventional print head. FIG. 10C is a cross-sectional view of a main part of a fourth conventional print head.

FIG. 11 is a plan view showing a conventional printing result.

[Explanation of symbols]

 Reference Signs List 1 armature 1a fulcrum 2 yoke 3 spring 4 coil 4a winding start end 4b winding end end 5 electromagnet mechanism 10 electromagnet 11 electromagnet 12A1 to 12A12 printing wire 12B1 to 12B12 printing wire

──────────────────────────────────────────────────続 き Continuation of the front page (72) Minoru Yamaguchi 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-63-102952 (JP, A) JP-A-1- 249459 (JP, A) JP-A-58-90965 (JP, A) JP-A-57-83464 (JP, A) JP-A-2-200448 (JP, A) JP-A-3-82551 (JP, A) Shokai 64-40534 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41J 2/225 B41J 2/27 B41J 2/30

Claims (2)

(57) [Claims] A plurality of print wires which claim 1 is an end to the printing paper is located opposite the equipped with that electromagnets mechanism to drive the print wire, fire end face of the print wire is opposite to the printing paper
It is arranged in the shape of a triangle, ellipse or parallelogram,
The printing wire from the center of the array of end faces of the printing wire
The electromagnet mechanism is arranged on a substantially circumference so that
And the two marks located at the forefront with respect to the scanning direction.
Between the two electromagnet mechanisms driving the U-shaped wire and the scanning method
Drive the two printing wires located at the rearmost position
A boundary line between the two moving electromagnet mechanisms
And before the electromagnet mechanism located on one side and the other
A print head, wherein the recording magnet mechanism is configured to generate a magnetic force in a reverse direction . 2. The two frontmost positions in the scanning direction.
Two electromagnet mechanisms for driving the printing wire and scanning direction
Drive the two printing wires located at the rearmost position
Energizing time of the two electromagnet mechanisms
2. The structure according to claim 1, wherein the energizing time is longer than the energizing time.
Print head as described.