JP2733125B2 - Wire dot print head - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire dot print head provided in a serial printer, and more particularly, to a tip arrangement of a plurality of wires provided in the wire dot print head.

<Prior Art> FIG. 3 is a diagram for explaining the wire tip arrangement of the conventional wire dot printing head provided at 24 dots Kanji printer, # 1 to # between the wire W ₁ to _W-24 24 tip Shows the distance relationship.

Conventionally, as shown in the figure, # 1, # 3 ...
# 23 odd wire W _ODD and # 2, # 4 located on the right
… _Length in the left-right direction with the even-numbered wire W _EVEN of # 24
₁₀ is related by the formula of (n 1/2) l, where l is the distance between dots of the basic dot matrix and n is a positive integer.

End of the wire W ₁ to _W-24 in such a distance relationship, by setting the integer n appropriately, actually is arranged, for example diamond. Also each wire W ₁ to _W-24, the respective wire W ₁
It is driven out by the energization of the electromagnet M ₁ ~M ₂₄ arranged in a circular shape like a schematic plan view of FIG. 4 provided corresponding to to _W-24. As shown in the schematic side view of FIG. 5, the wire dot print head 1 has a flat
Are arranged facing the cylindrical platen 2, and perform printing while moving in the left-right direction (the direction perpendicular to the paper surface) along the platen 2.

The end of the wire W ₁ to _W-24 as described above are arranged divided into two groups, the distance between dots l the distance between that group
Of by shifting only staggered print timing 1 / 2l an integral multiple, current supplied to the electromagnet M ₁ ~M _24, i.e. it is possible to halve the peak value of the power consumption of the print head, small and as a result the power supply device And cost can be reduced.

By the way, the electromagnets M _{1 to} M that are operated with the respective wires W _{1 to} W _24
24 causes magnetic interference between adjacent magnets because each magnetic flux goes around to an adjacent electromagnet. This magnetic interference has no problem between the electromagnets having the same printing timing and the same current waveform phase, but different electromagnets having different printing timings and different current waveform phases, that is, different groups of corresponding tip arrangements of the wires. The following problems occur between the electromagnets. In the case of a conventional print head, the problematic electromagnet is the # 1 wire adjacent to the top of the print head.
Electromagnets M ₁ and # 2 of electromagnets M ₂ of the wire W ₂ of W _1, and an electromagnet M ₂₃ of the wire W ₂₃ adjacent # 23 at the bottom of the print head #
An electromagnet M ₂₄ with ₂₄ wires W ₂₄ .

As shown in the waveform diagram of FIG. 6, a current waveform I applied to electromagnets M ₁ and M ₂₃ corresponding to one group and a current waveform II applied to electromagnets M ₂ and M ₂₄ corresponding to the other group. In particular, in the case of high-speed printing in which the phase difference becomes a quarter period (1 / 4T), the adverse effect of the magnetic interference appears significantly. That is, the current waveform II of the electromagnets M ₂ and M ₂₄ is originally the same as the current waveform I as shown by the broken line, but actually, the magnetic waveforms of the electromagnets M ₁ and M _{23 to which} the preceding current waveform I is given are given. The interference delays the rise as shown by the solid line. As a result, the disturbed reciprocating cycle of the wire W ₂ and the wire W _24, blurring or printing, de-dot printing occurs in the worst case.

<Problems to be Solved by the Invention> In a wire dot print head in which the ends of the wires are divided into two groups having different print timings, as described above, the magnetic interference between the different electromagnets in the corresponding groups has a structure. Depends on the degree of difference,
It occurs inevitably.

However, the problem with the conventional wire dot print head is that the grouping of the tip arrangement of the wires is divided into two parts, left and right. This is in that it appears as a wire located at a lower position and a wire located at a lower position.

As shown in FIG. 5, since the print head 1 having the flat head end face 3 faces the cylindrical platen 2, the head gap G1 at the upper position or the lower position of the print head ₁ is intermediate. Head gap G _{2 at} position
Greater than. Therefore, wires W ₁ , W ₂ and # 23 of # 1 and # 2
The stroke of the wire W _23, W ₂₄ and # 24 are elongated, and correspondingly longer roundtrip time to the platen 2 of the wires _{W 1, W 2, W 23} , W 24. When the reciprocating cycle is disturbed by such a long stroke wire, dot removal printing naturally tends to occur.

The present invention solves such a problem in the conventional wire dot print head, so that the adverse effect due to magnetic interference,
An object of the present invention is to provide a wire dot print head in which fading of printing and dot printing are unlikely to occur, so as to appear with the most advantageous wire on the stroke.

<Means for Solving the Problems> In order to achieve the above object, a wire dot printing dot according to the present invention is ejected to the platen side from a head tip surface facing a cylindrical platen and the head tip surface. Multiple wires and each wire individually, and
A plurality of electromagnets that launch the wire by energization, and perform printing by punching the plurality of wires while moving in the left-right direction along the platen, and furthermore, the plurality of wires, The tip is arranged to face the platen, and is arranged in a direction orthogonal to the axial direction of the platen, and further vertically above and below a position where the facing distance between the platen and the head tip surface is minimized. Each of the electromagnets corresponding to the wire group above the boundary of the grouping is energized at the same timing and corresponds to the wire group below the boundary of the grouping. Each of the electromagnets is the same and is energized at a different timing from the electromagnet corresponding to the upper wire group, and corresponds to the upper wire group. Between the electromagnet and each electromagnet corresponding to the lower wire group, only electromagnets corresponding to wires adjacent to each other across the boundary of the grouping are arranged adjacent to each other. is there.

<Operation> According to the wire dot print head having the above configuration, the grouping of the tip arrangement of a plurality of wires is performed at the position where the facing distance between the platen and the tip face of the head becomes minimum. In addition, each electromagnet arranged adjacent to each other and energized at a different timing strikes adjacent wires across the boundary of the grouping.

Therefore, even if magnetic interference occurs between electromagnets that are adjacent to each other and have different energization timings, the adverse effect due to the magnetic interference appears on the wire that is the most advantageous in stroke. That is, for example, even if the reciprocating cycle of the wire is disturbed by magnetic interference between adjacent electromagnets, the effect appears on the wire having the shortest reciprocating time, that is, the wire having a sufficient time in terms of time.

An embodiment of the present invention will be described below with reference to the drawings.
Note that the components in the drawings of the embodiments are denoted by the same reference numerals because they are not different from the conventional example.

Figure 1 is a view for explaining a wire tip arrangement in a wire dot printing head of the present invention provided 24 dot Chinese character printer, the distance relationship between the tips of the wire W ₁ to _W-24 of # 1 to # 24 Is shown.

As shown in the figure, in the print head of the present invention, the grouping of the array of the wire tips is divided into upper and lower parts. That is, wires # 1 to # 12 located in the upper half of the print head
And W ₁ to _W-12, the wire W ₁₃ of # 13 to # 24 located in the lower half-
W ₂₄ and two groups are formed. And in each group, the odd numbered wire W located on the left
And _ODD, the distance L ₁ in the lateral direction of the wire W _EVEN even-numbered positioned on the right side, the distance between dots l dot matrix made up of the core is set to a positive integer n times, printing timing is simultaneous ing. On the other hand, between the two groups, the print timing is shifted by arranging them by 1 / 2l.

FIG. 2 is a diagram showing an example in which the above-mentioned tip arrangement is applied to a rhombus wire arrangement type print head. In the case of this application is arranged each set of wire tip up and down and that of those with even-numbered odd-numbered wire W ₁ to _W-24 in the two portions set, in the horizontal direction between each pair the distance L ₂ or L _3, and set to an integral multiple of the distance between dots l a rhombus, are arranged by shifting their group between only 1 / 2l further grouped vertically.

The wires W _{1 to} W ₂₄ of the print head according to the present invention
Hammered out by the energization of the electromagnet M ₁ ~M ₂₄ arranged in a circle as shown in FIG, also the printhead, as shown in FIG. 5, a platen that head distal end surface 3 is cylindrical, which forms a plane 2 and the platen 2
Is performed while moving in the left-right direction (the direction perpendicular to the paper surface) along. That is, the print head includes the head end face 3 facing the platen 2 and the plurality of wires W _{1 to} W ₂₄ that are ejected from the head end face 3 toward the platen 2 by energizing the electromagnets M _{1 to} M ₂₄ . At the same time, the tips of these wires W _{1 to} W ₂₄ are arranged opposite to the platen 2 and are arranged on the head tip surface 3 in a direction orthogonal to the axial direction of the platen 2, and two groups having different printing timings Are arranged separately. These points are the same as in the conventional example.

However, as described above, at the tip array of the wire W ₁ to _W-24, when the two groups of different print timing were divided up and down, the vertical direction of the intermediate position of the print head,
That platen 2 and facing distance between the head distal end face 3 (head gap) can border groups smallest position, thus the wire W ₁₁ and W ₁₃ adjacent in the boundary and the wire W ₁₂ and W _14, Togaotto people will be affected by the magnetic interference between the magnetic interference, and the electromagnet M ₁₂ and M ₁₄ between the electromagnet M ₁₁ and M ₁₃ which are adjacent. For example, the electromagnets M ₁ ~M ₁₂ corresponding to the upper group the current waveform I in FIG. 6, also in the electromagnet M ₁₃ ~M ₂₄ corresponding to the group of lower, four from the current waveform I a fraction of period in (1 / 4T) only as delayed current waveform II phase is given printing, the wire W ₁₃ and W ₁₄ to be struck by the electromagnet M ₁₃ and M _14, adverse effects of magnetic interference, such as reciprocating rhythm disturbances Appears.

But as shown in FIG. 5, since the head gap G ₂ is smallest in the vertical direction of the intermediate position of the print head, the stroke is short the wire W ₁₃ and W ₁₄ in this position, the much to the platen 2 Round trip time is also short. Therefore, even the reciprocating cycle of the short wire W _13, W ₁₄ of these strokes is disturbed, because the temporally can afford, printing of blur and de-dot printing hardly occurs.

That is, in the wire dot print head of the present invention, since the adverse effect due to the magnetic interference appears on the most advantageous wire in the stroke, the fading of the print and the dot print are prevented.

<Effects of the Invention> As described above, according to the present invention, the peak value of the power consumption can be halved, and furthermore, the fading of the printing and the dot-free printing caused by the magnetic interference can be prevented, and the high printing quality can be secured. An excellent wire dot print head can be realized.

[Brief description of the drawings]

FIG. 1 is a view for explaining an arrangement of wire tips in an embodiment of the present invention, FIG. 2 is a view showing an application of the wire tip arrangement in an embodiment of the present invention, and FIG. FIG. 4 is a schematic plan view showing an arrangement of electromagnets, FIG. 5 is an immediate sectional view showing an arrangement of a wire dot print head and a platen, and FIG. 6 is given to an electromagnet. FIG. 4 is a waveform diagram showing a current waveform. W ₁ to _W-24 ...... wire, M ₁ ~M ₂₄ ...... electromagnet 1 ...... wire dot print head, 2 ...... platen, 3 ...... head distal end surface.

Claims (1)

(57) [Claims] 1. A head tip surface facing a cylindrical platen, a plurality of wires punched out from the head tip surface to the platen side, the wires individually corresponding to each wire, and the wires are launched by energization. A plurality of electromagnets for performing the printing by ejecting the plurality of wires while moving in the left and right direction along the platen, the plurality of wires, the tip of the platen, the platen And a wire group which is arranged in a direction orthogonal to the axial direction of the platen, and which is vertically divided into two parts at a position where a facing distance between the platen and the head tip surface is minimum. Each electromagnet corresponding to a group of wires above the boundary of the grouping is energized at the same timing, and Each electromagnet corresponding to a wire group below the boundary of division is energized at the same time and at a different timing from the electromagnet corresponding to the upper wire group, and each electromagnet corresponding to the upper wire group and the A wire dot print head, wherein only electromagnets corresponding to wires adjacent to each other across the boundary of the grouping are arranged adjacent to each other between electromagnets corresponding to a lower wire group.