JP3035878B2 - Wire dot 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 wire dot print head mounted on a serial printer or the like.

[0002]

2. Description of the Related Art As an impact type wire dot print head mounted on a serial printer or the like, a so-called spring-charge type wire dot print head is known, and its structure is shown in FIG. Hereinafter, the configuration and operation of the main part will be described with reference to FIG. First, at the time of non-printing, the magnetic flux generated by the permanent magnet 50 is applied to any of the first yoke 51, the base plate 52, the core 53, the leaf spring 54, the armature 55, the armature yoke 56, the spacer 57, and the second yoke 58. The armature 55 supported by the leaf spring 54 also passes through a magnetic path made of a magnetically permeable material and returns to the permanent magnet 50 again.
Is sucked into the core 53 side.

On the other hand, at the time of printing, as shown in FIG.
, A magnetic flux in the opposite direction to the magnetic flux of the permanent magnet 50 passing through the core 53 is generated, and the armature 55 is released from the attracted state. Thereby, the armature 55
Swings with the resilient force of the leaf spring 54, and the printing wire 61 fixed to the tip of the armature 55 is shown in FIG.
6, and protrudes from the wire guide 62,
It collides with a platen (not shown) via the ink ribbon 63 and the print medium 64. Doing dot printing in this way,
When the armature 55 is again attracted to the core 53 by the magnetic flux of the permanent magnet 50, one printing operation ends.

The above-mentioned wire dot print head employs these 1
A plurality of printing elements for dots are radially arranged in a number corresponding to the number of printing dots.
Except for the electromagnet 60 and the printing wire 61, a plurality of parts are integrally formed and assembled.

Meanwhile, a current wire dot print head has a so-called 24
Pin heads are the mainstream, and it is necessary to further increase the number of pins in order to achieve higher quality printing than the current state. In order to realize this multi-pin configuration, two main means are considered, one of which is to increase the number of printing elements arranged side by side on the same plane, and the other is shown in FIG. As shown, a print head unit including a permanent magnet 50, an armature 55, an electromagnet 60 and each fixing member is stacked in a plurality of stages, and a print wire 61 in each stage is projected from a wire guide 62. The latter is described in Japanese Utility Model Laid-Open No. 55-39880 and Japanese Patent Publication No. 58-1983.
It is also published in -3836.

[0006]

However, in order to increase the number of pins, when the former means is adopted,
There is a limit to the number of printing elements incorporated in the head, and the entire head expands in the circumferential direction, which hinders miniaturization of the printer. On the other hand, when the latter means is employed, it is possible to improve the degree of integration of print elements by reducing the thickness of each component of the print head unit without enlarging in the circumferential direction. However, the printing medium 6
Since the length of the printing wire 61 is naturally different between the front side close to 4 and the rear side opposite thereto, the equivalent mass of the movable portion including the leaf spring 54, the armature 55 and the printing wire 61 is reduced to the front side. When the movable section is driven under the same driving conditions in each stage, the operation of the movable section in the subsequent stage is inevitably delayed.

For example, the next printing operation is started on a movable portion (leaf spring 54, armature 55, printing wire 61) that has been accelerated in the direction of being sucked toward the core 53 by colliding with the printing surface. When the coil 59 is energized at the timings shown in FIGS. 18A and 18B, it takes time to switch the moving direction of the movable part on the subsequent stage by an amount corresponding to the increase in the equivalent mass. Problems such as the suction of the printing wire 61 without colliding with the printing surface or the printing wire 61 being in a state of being protruded without being sucked by the next energization occur, and as a result, dot missing, printing unevenness, ribbon hooking occur. This causes adverse effects such as wire breakage. Therefore, when the energization timing of the coil 59 is driven in accordance with the operation characteristics of the subsequent stage, this time, FIG.
As shown in FIG. 8 (c), a delay occurs in the return of the movable section on the preceding stage (broken line in the figure), and it becomes impossible to secure the printing force using the rebound and to reduce the immobility time. A shift occurs, causing the same adverse effect as described above. Further, even when the driving time is adjusted according to the operating characteristics of the subsequent stage, as shown in FIG.
A delay occurs in the return of the movable section on the front side (broken line in the figure), causing the same problem as described above.

Further, in the conventional wire dot print head, as shown in FIG. 19, a plurality of stages of print head units are connected by connecting screws 65, so as shown in FIG. When the energization is completed, and the movable part on the subsequent stage is attracted to the core 53 side, the coil 5 on the former stage
19, the magnetic flux generated by energizing the coil 59 on the front side flows into the core 53 on the rear side through the connecting screw 65 as shown in FIG.
It acts to cancel the zero magnetic flux. As a result, the suction force on the movable part is weakened on the rear side, so that a stable printing operation can be obtained as shown by a broken line in the figure when the influence of the magnetic flux on the front side is not affected. If it is received, as shown by the solid line in the figure, the return of the movable portion is delayed by that amount, and the printing operation becomes unstable, causing problems such as missing dots and hooking of the ribbon.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has an object to stabilize a printing operation of a movable portion in each stage in a wire dot print head in which print head units are stacked in a plurality of stages. Aim.

[0010]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above object, and according to the first aspect of the present invention, there are provided a plurality of antennas each having a print wire fixed to a tip thereof.
-Movable with the armature swingably supported by a leaf spring
And a plurality of parts forming a head body while sandwiching a leaf spring
Fixing members and a permanent magnet interposed between the fixing members
And placed on the base plate facing the armature.
Magnet consisting of a wound core and a coil wound around the core
The print head unit having
Drive current to the electromagnet to strike the magnetic flux of the permanent magnet.
The armature with the spring force of the leaf spring.
To print on each stage of the print head unit.
Print each wire by projecting it from the wire guide.
Print head unit in a wire dot print head.
Each stage according to the equivalent mass of the movable part in each stage.
Moving parts in each stage by changing the thickness of the fixed member
The driving condition is set.

[0011] In the second aspect of the present invention, respectively in the distal end
Leaf spring with multiple armatures with print wires attached
The movable part, which is supported to be able to swing freely, and the leaf spring
A plurality of fixing members forming the head body while
To the permanent magnet interposed between the fixed members and the armature.
Core and core installed on the base plate
Print head having an electromagnet comprising a wound coil
Units are stacked in multiple levels and drive power is supplied to the electromagnet.
By supplying current to counteract the magnetic flux of the permanent magnet,
The armature is swung with the spring force of the spring, and
Print wires at each stage of the
Wire dot printing, which prints by projecting from the
In each stage of the print head unit
Magnetomotive force of the permanent magnet at each stage according to the equivalent mass of the part
To set the driving conditions for the movable parts in each stage.
Configuration.

According to the third aspect of the present invention, each
Leaf spring with multiple armatures with print wires attached
The movable part, which is supported to be able to swing freely, and the leaf spring
A plurality of fixing members forming the head body while
To the permanent magnet interposed between the fixed members and the armature.
Core and core installed on the base plate
Print head having an electromagnet comprising a wound coil
Units are stacked in multiple levels and drive power is supplied to the electromagnet.
By supplying current to counteract the magnetic flux of the permanent magnet,
The armature is swung with the spring force of the spring, and
Print wires at each stage of the
Wire dot printing, which prints by projecting from the
In the pad, the first base plate is engaged with the
The first engagement groove is engaged with the top plate on the subsequent stage.
2 engagement groove and through hole for passing the printing wire on the rear side
The print head unit is
It is configured to join the objects.

[0013] In the present invention of claim 4, wherein, according to claim 3, wherein
In the invention, the guide member guides and supports the printing wire.
A guide portion is provided.

According to the fifth aspect of the present invention, the third aspect of the present invention provides
In the invention, the joint member is made of a material having high thermal conductivity.
Has formed.

[0015]

In the wire dot print head according to the first aspect, the equivalent of the movable portion in each stage of the print head unit.
Depending on the mass, for example, the thickness of the fixing member on the front
Thicker than above, the driving conditions of the movable part in each stage
By setting, each
When the movable part of the stage is driven, the armature
The flowing magnetic flux decreases, and the magnetic absorption by the permanent magnet
Appropriate for the moving time of the movable part on the front side because the attractive force is weakened
Delay, and as a result, both front and rear sides are stable
A printing operation can be obtained.

In the wire dot print head according to the second aspect, the movable portion of each stage of the print head unit is
Depending on the equivalent mass, for example, the magnetomotive force of the front-stage permanent magnet
By making it smaller than the subsequent stage,
By setting the driving conditions, it is possible to match the operating characteristics of the subsequent stage.
When the movable parts of each stage are driven together,
The attraction force acting on the tur is reduced and the drive current rises.
Because the rise is slow and the input energy decreases,
A moderate delay occurs in the moving time of the movable part on the step side,
As a result, stable printing operation can be obtained on both the front and rear sides.
Become so.

According to the third aspect of the present invention, the front base plate is connected to the first engagement groove.
And the second engagement groove
The print head units together while engaging the
Print head units at each stage by joining with members
Are no longer subject to magnetic interference.

In the wire dot print head according to the fourth aspect, the joint member is provided with a guide portion, and the guide portion is provided.
The guide wire guides and supports the printing wire,
The printing wire support condition is stable, and the printing wire
It is prevented beforehand.

In the wire dot print head according to the fifth aspect, the joint member is made of a material having high thermal conductivity.
Heat generated by the print head unit at each stage
Is efficiently radiated to the outside.

[0020]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a view for explaining a first embodiment of a wire dot print head according to the present invention. First, in the wire dot print head according to the first embodiment, as shown in FIG. 1 (a), print wires 1 arranged corresponding to respective dot positions are fixed to the tips of armatures 2 respectively, The movable portion 2 is supported by a leaf spring 3 so as to be swingable. A first yoke 4, a second yoke 5, a spacer 6
In both cases, a magnetically permeable annular member such as the armature yoke 7 is integrally laminated, and the head body is formed by the plurality of fixing members.
A permanent magnet 8 is provided between the first yoke 4 and the second yoke 5.
Is interposed. On the other hand, below armature 2,
An electromagnet 11 composed of a core 9 and a coil 10 wound around the core 9 is arranged to face each other.
Is installed on the base plate 12. In the first embodiment, the print head units having the above configuration are stacked in a plurality of stages, for example, two stages as shown in the figure, thereby forming the present wire dot print head.

Here, in the configuration of the first embodiment, the shape of the printing wire 1 on the front side (upper side in the figure) near the printing medium (not shown) side and the rear side (lower side in the figure) on the opposite side. By making the shape different from the shape of the print wire 1, the equivalent mass of the movable portion (1, 2, 3) in each stage of the print head unit is set to be the same. That is, as shown in FIG. 1 (b), the diameter of the tip 1a of the printing wire 1 in each stage is set to be the same, and the length of the joist 1b, which is larger than that, is changed. Have the same equivalent mass of the movable part.

Next, the operation of the wire dot print head having the above configuration will be described. First, in the non-printing state, the magnetic flux generated by the permanent magnet 8 is
A magnetic closed circuit is formed which flows to the core 9 through the base plate 12 and returns to the permanent magnet 8 again through the armature 2, the armature yoke 7, and the spacer 6, and is supported by the leaf spring 3 by the action of the magnetic closed circuit. The armature 2 is sucked toward the core 9 and is in a deflected state.

On the other hand, at the time of printing, by energizing the coil 10 to excite the electromagnet 11, a magnetic flux in the opposite direction to the magnetic flux of the permanent magnet 8 passing through the core 9 is generated, thereby canceling both magnetic fluxes. The armature 2 is released from the suction state (biased state). When the suction of the armature 2 is released, the armature 2 moves in the direction away from the core 9 by the elastic force of the leaf spring 3, and the printing wire 1 fixed to the tip of the armature 2 protrudes from the wire guide 13. It collides with a platen via an ink ribbon and a print medium (not shown).

Here, in the first embodiment, since the equivalent mass of the movable portion is set to be the same by changing the shape of the printing wire 1 of each stage, the printing head unit of each stage is set at the time of printing. Even when driven under the same driving conditions,
As shown in FIG. 2, the wire displacement (L) is synchronized with the supply timing of the drive current (I) on both the former stage and the latter stage, so that a stable printing operation can be obtained.

In the configuration of the first embodiment, the equivalent mass of the movable portion is set to be the same by changing the shape of the printing wire 1 in each stage. However, the present invention is not limited to this, and for example, By changing the material specific gravity of the printing wire 1 as well, the equivalent mass of the movable portion in each stage can be set to be the same as described above, and the printing operation can be stabilized. Further, using the armatures 2 having the same magnetic permeability as each other without changing the material and shape of the printing wire 1, for example, as shown in FIG.
It is also possible to set the width W1 of the rear armature 2 together with the groove width of the armature yoke 7 to be smaller than the width W2 of the front armature 2, or to change the material specific gravity of the armature 2 in each stage as described above. In the same manner as described above, the equivalent mass of the movable portion in each stage can be set to be the same, and the printing operation can be stabilized.

FIG. 4 is a view for explaining a second embodiment of the wire dot print head according to the present invention. In the wire dot print head of the second embodiment, the driving conditions of the movable section are set by changing the number of turns of the coil 10 in each section according to the equivalent mass of the movable section in each section of the print head unit. . That is, in the second embodiment, the number of turns of the coil 10 on the front side is set to be larger than the number of turns of the coil 10 on the rear side so that the printing operation of each stage is stabilized. As a result, as shown in FIG. 5, when the number of turns of the coil 10 is set to be the same in each stage, the timing with the drive current is shifted due to the difference in the equivalent mass of the movable part as shown by the solid line in the figure. When the operation of the movable part is unstable, but the number of turns of the coil 10 on the front stage is set to be larger than that on the subsequent stage, the movable part of each stage is driven in accordance with the operating characteristics of the latter stage. As a result, the rising portion P of the driving current (I) at the former stage becomes duller than that at the latter stage, and the input energy Ip is reduced accordingly. Therefore, the time T1 required for the movable portion to start moving as shown by the broken line in the drawing. The time T2 from when it starts moving to when it comes into contact with the printing surface and returns is appropriately extended, and as a result, a stable printing operation can be obtained on both the front stage and the rear stage.

In the second embodiment, the driving conditions of the movable section in each stage are changed by changing the number of turns of the coil 10 on the front stage and the rear stage in accordance with the equivalent mass of the movable portion in each stage of the print head unit. However, the present invention is not limited to this. For example, by making the wire diameter of the coil 10 on the front stage smaller than the wire diameter of the coil 10 on the rear stage, the printing operation can be stabilized by the same operation as described above. Can be achieved.

FIG. 6 is a view for explaining a third embodiment of the wire dot print head according to the present invention. In the wire dot print head of the third embodiment, the driving condition of the movable section is set by changing the thickness of the fixed member of each section according to the equivalent mass of the movable section in each section of the print head unit. . That is, in the third embodiment, the thickness of the spacer 6 on the front side is set to be larger than the thickness of the spacer 6 on the rear side so that the printing operation of each stage is stabilized. As a result, as shown in FIG. 7, when the thickness of the spacer 6 is set to be the same for each step, the timing with the drive current is shifted due to the difference in the equivalent mass of the movable part as shown by the solid line in the figure. If the operation of the movable part is unstable, but if the thickness of the front-stage spacer 6 is set to be thicker than that of the rear-stage side, the magnetic flux flowing through the armature 2 at the front-stage side decreases, and the permanent Since the magnetic attraction force of the magnet 8 is weakened, the movable portion of each stage is driven in accordance with the operating characteristics of the subsequent stage, so that the rising portion P of the drive current (I) on the preceding stage as shown by the broken line in the drawing. Return time until the armature 2 is attracted to the core 9 as much as the magnetic attraction force of the permanent magnet 8 is weakened while the input energy Ip increases and the time T1 required for the movable part to start moving is shortened. Moderate delay occurs in T2, which results in the stabilized operation characteristics in both of the front side and the rear stage side is obtained.

In the third embodiment, the driving conditions of the movable parts of each stage are set by changing the thickness of the spacer 6 according to the equivalent mass of the movable parts in each stage.
The present invention is not limited to this. For example, by changing the shape (mainly the thickness) and the material (mainly the magnetic permeability) of the first yoke 4 and the second yoke 5, etc., as the fixing member other than the spacer 6, the same employment as described above. Thereby, the printing operation can be stabilized.

FIG. 8 is a view for explaining a fourth embodiment of the wire dot print head according to the present invention. In the wire dot print head according to the fourth embodiment, the driving condition of the movable section is set by changing the magnetomotive force of the permanent magnet 8 in each section according to the equivalent mass of the movable section in each section of the print head unit. I have. That is, in the fourth embodiment, the magnetomotive force of the permanent magnet 8 at the front stage is changed by changing the magnetizing voltage when the permanent magnet 8 is magnetized so that the printing operation at each stage is stabilized. 8 is set smaller than the magnetomotive force. Accordingly, as shown in FIG. 9, when the magnetomotive force of the permanent magnet 8 is set to be the same for each stage, the timing with the drive current is shifted due to the difference in the equivalent mass of the movable part as shown by the solid line in the figure. When the magnetomotive force of the front-stage permanent magnet 8 is set smaller than that of the rear-stage side, the attraction force acting on the armature 2 at the front-stage side decreases. At the same time, as shown by the broken line in the figure, the rising portion P of the drive current (I) becomes dull and the input energy Ip decreases. Accordingly, by driving the movable portions of each stage in accordance with the operating characteristics of the subsequent stage, the time T1 required for the movable portions to start moving as shown by the broken line in the preceding stage is shortened on the front stage side, while the operation on the armature 2 is reduced. The return time T2 of the movable portion after hitting the printing surface by an amount corresponding to the reduced suction force causes an appropriate delay, and as a result, a stable printing operation can be obtained on both the front stage and the rear stage.

FIG. 10 is a view for explaining a fifth embodiment of the wire dot print head according to the present invention. In the wire dot print head according to the fifth embodiment, the driving condition of the movable part is set by changing the resilient force of the leaf spring 3 at each stage according to the equivalent mass of the movable part at each stage of the print head unit. ing. That is, in the fifth embodiment, the effective width V1 of the leaf spring 3 in the preceding stage is set wider than the effective width V1 of the leaf spring 3 in the subsequent stage so that the printing operation in each stage is stabilized. The spring force of the leaf spring 3 is set to be larger than the spring force of the leaf spring 3 on the subsequent stage. Thus, as shown in FIG. 11, when the effective width of the leaf spring 3 is set to be the same in each stage, the timing with the drive current is shifted due to the difference in the equivalent mass of the movable part as shown by the solid line in the figure. When the resilient force of the front-side leaf spring 3 is set to be larger than that of the subsequent side, the operation of the movable section becomes unstable. By driving the movable portion, the time T1 required for the movable portion to start moving as shown by the dashed line in the drawing is reduced on the front stage side, while the spring force of the leaf spring 3 abuts on the printing surface by the large amount. As a result, a delay occurs in the return time T2 of the movable portion from the printer, and as a result, a stable printing operation can be obtained on both the former stage and the latter stage.

In the fifth embodiment, the driving conditions of the movable part on the front stage and the rear stage are appropriately set by changing the effective width of the leaf spring 3 in each stage. For example, the spring constant of the leaf spring 3 can be changed without changing the magnetic resistance of the head body,
Alternatively, by changing the thickness or the effective area of the leaf spring 3, the printing operation can be stabilized by the same operation as described above.

FIG. 12 is a view for explaining a sixth embodiment of the wire dot print head according to the present invention. In the wire dot print head of the sixth embodiment, the movable time of each stage is changed by changing the drive time to the electromagnet 11 on the front stage side and the rear stage side in accordance with the equivalent mass of the movable portion in each stage of the print head unit. The drive conditions for the unit are set. That is, in the sixth embodiment, the driving time to the electromagnet 11 in the former stage is set shorter than that in the latter stage so that the printing operation in each stage is stabilized. Accordingly, when the driving time for the electromagnet 11 is set to be the same for each stage, the next operation is performed before the movable portion completely returns to the previous stage as shown by the broken line in FIG. When the drive time for the front stage is set to be shorter than that for the rear stage, the shift in timing such as the supply of drive current for By driving the movable portions of each stage in accordance with the operating characteristics of the subsequent stage, the above-described timing shift at the preceding stage is eliminated as shown in FIG. 12B, and the movable portions are completely returned. In this state, the drive current (I) for the next operation is supplied, and as a result, a stable printing operation can be obtained on both the first and second stages.

In the sixth embodiment, the timing deviation is eliminated by changing the driving time of the former stage and the latter stage. However, the present invention is not limited to this.
By changing the drive voltage when exciting the electromagnet 11,
The operation characteristics can be stabilized by the same operation as described above.

FIG. 13 is a view for explaining the structure of a joint member used for connecting the print head units in this embodiment. FIG. 14 shows a state in which the print head units are actually connected to each other using the joint member. FIG. The illustrated joint member 20 includes a first fitting portion 21 fitted into the print head unit on the front side, a spacer portion 22 sandwiched between the print head units on the front side and the rear side, and a print head on the rear side. A second fitting portion 23 fitted into the unit is provided. And the first
A first engagement groove 24 is formed between the fitting portion 21 and the spacer portion 22 for engaging the base plate on the front stage side.
A second engagement groove 25 is formed between the spacer portion 22 and the second fitting portion 23 so as to be engaged with the rear-side top plate 14. Further, the first fitting portion 21 and the second fitting portion 23 are formed with protrusions 21a and 23a, respectively, protruding toward the first engagement groove 24 and the second engagement groove 25, respectively. The movement of the print head unit in the rotation direction is regulated by these projections 21a and 23a. Further, a through hole 26 is formed in the axis of the joint member 20, and the printing wire on the rear side is drawn out to the front side through the through hole 26. A guide portion 27 having a plurality of fine holes (not shown) is incorporated in the middle of the above-described through hole 26. 1 is guided and supported.

As described above, in the wire dot print head of this embodiment, the print head units of each stage are connected to each other via the joint member 20, so that when the print head units are connected using the connecting screws as in the conventional structure. Can avoid the influence of magnetic interference. Further, a guide portion 27 is provided in the middle of a through hole 26 formed in the joint member 20 so that the guide portion 27
, The printing wire 1 is guided and supported, so that the supporting state of the printing wire 1 in each stage becomes very stable. In addition, when the mold resin is injected into the print head unit, the guide portion 27 is used. Resin leakage is prevented.

In addition, in the wire dot print head of this embodiment, since the joint member 20 is made of a material having high thermal conductivity (for example, aluminum material), the joint member 20 itself performs a so-called heat sink function. In addition, the heat generated by the print head unit in each stage is efficiently radiated to the outside.

[0038]

As described above, according to the present invention,
The equivalent mass of the movable part in each stage of the print head unit
By changing the thickness of the fixing member at each stage,
By setting the driving conditions of the movable part in the stage,
Stable printing operation can be obtained on both
It becomes possible. As a result, missing dots and printing
Troubles such as la, ribbon hooking and wire breakage have been resolved
You.

According to the present invention, a print head unit is provided.
In each stage according to the equivalent mass of the movable part in each stage
Moving parts in each stage by changing the magnetomotive force of the permanent magnet
By setting the driving conditions for both the front and rear stages,
Thus, a stable printing operation can be obtained. to this
More, missing dots, uneven printing, hooking on ribbon, wire
Problems such as breakage are eliminated.

Further, according to the present invention, the print head units of each stage are connected to each other via the joint member, so that the influence of magnetic interference when connecting using the connecting screws as in the conventional structure is avoided. It is possible to do. In addition, by providing the guide member for guiding and supporting the printing wire in the above-described joint member, the supporting state of the printing wire in each stage is very stable, and thereby it is possible to prevent the printing wire from being broken. In addition, since the above-described joint member is made of a material having high thermal conductivity, the heat generated by the print head units in each stage can be efficiently radiated to the outside. Fusing can be prevented, and the stop time for cooling can be shortened by an increase in the heat radiation efficiency, so that the throughput as a printer can be improved.

[Brief description of the drawings]

FIG. 1 is a first view of a wire dot print head according to the present invention.
It is a figure explaining an Example.

FIG. 2 is a diagram illustrating operating characteristics of a movable unit in the first embodiment.

FIG. 3 is a view for explaining another embodiment of the first embodiment.

FIG. 4 shows a second example of the wire dot print head according to the present invention.
It is a figure explaining an Example.

FIG. 5 is a diagram illustrating operating characteristics of a movable unit in the second embodiment.

FIG. 6 shows a third example of the wire dot print head according to the present invention.
It is a figure explaining an Example.

FIG. 7 is a diagram illustrating operating characteristics of a movable unit according to a third embodiment.

FIG. 8 shows a fourth example of the wire dot print head according to the present invention.
It is a figure explaining an Example.

FIG. 9 is a diagram for explaining the operation characteristics of the movable section in the fourth embodiment.

FIG. 10 is a diagram illustrating a fifth embodiment of the wire dot print head according to the present invention.

FIG. 11 is a diagram illustrating operating characteristics of a movable unit according to a fifth embodiment.

FIG. 12 is a diagram illustrating a sixth embodiment of the wire dot print head according to the present invention.

FIG. 13 is a diagram illustrating the structure of a joint member.

FIG. 14 is a diagram illustrating a state of connection by a joint member.

FIG. 15 is a diagram illustrating the structure of a conventional wire dot print head.

FIG. 16 is a diagram illustrating the operating characteristics of a movable section in a conventional example.

FIG. 17 is a diagram illustrating a conventional structure in which print head units are stacked in a plurality of stages.

FIG. 18 is a diagram illustrating a conventional problem.

FIG. 19 is a diagram illustrating the principle of magnetic interference.

FIG. 20 is a diagram illustrating a problem caused by magnetic interference.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Print wire 2 Armature 3 Leaf spring 6 Spacer 7 Armature yoke 8 Permanent magnet 9 Core 10 Coil 11 Electromagnet 12 Base plate 13 Wire guide 20 Joint member 24 First engagement groove 25 Second engagement groove 26 Through hole 27 Guide part

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-164550 (JP, A) JP-A-59-95164 (JP, A) JP-A-2-164550 (JP, A) JP-A 61-95 228966 (JP, A) JP-A-63-30259 (JP, A) JP-A-1-148563 (JP, A) JP-A-5-72445 (JP, U) JP-A-1-97948 (JP, U) Japanese Utility Model 39839 (JP, U) Japanese Utility Model 63-189638 (JP, U) Japanese Utility Model Utility Model 55-39880 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41J 2/235 B41J 2/28 B41J 2/30 B41J 2/505-2/515

Claims (5)

(57) [Claims] 1. A printing wire is fixed to each end.
Plural armatures are swingably supported by leaf springs
And a head body while sandwiching the leaf spring.
A plurality of fixing members forming
And a base facing the armature.
Core mounted on a plate and wound on said core
Printhead unit having an electromagnet comprising
And the electromagnet is driven by a drive current.
To cancel the magnetic flux of the permanent magnet,
The armature is swung by the elastic force of the leaf spring.
The printing water in each stage of the printing head unit.
Printing is performed by projecting the ears from the wire guides
In a wire dot print head, the movable portion in each stage of the print head unit, etc.
Thickness of the fixing member at each stage according to the valence mass
By changing the driving conditions of the movable section in each of the stages.
A wire dot print head characterized in that: 2. A printing wire is fixed to each end.
Plural armatures are swingably supported by leaf springs
And a head body while sandwiching the leaf spring.
A plurality of fixing members forming
And a base facing the armature.
Core mounted on a plate and wound on said core
Printhead unit having an electromagnet comprising
And the electromagnet is driven by a drive current.
To cancel the magnetic flux of the permanent magnet,
The armature is swung by the elastic force of the leaf spring.
The printing water in each stage of the printing head unit.
Printing is performed by projecting the ears from the wire guides
In a wire dot print head, the movable portion in each stage of the print head unit, etc.
Magnetomotive force of the permanent magnet in each of the stages according to the valence mass
By changing the force, the driving force of the movable
Dot print head,
De. 3. A printing wire is fixed to each end.
Plural armatures are swingably supported by leaf springs
A movable portion composed of Te, while nipping the plate spring f head main body
A plurality of fixing members forming
And a base facing the armature.
Core mounted on a plate and wound on said core
Printhead unit having an electromagnet comprising
And the electromagnet is driven by a drive current.
To cancel the magnetic flux of the permanent magnet,
The armature is swung by the elastic force of the leaf spring.
The printing water in each stage of the printing head unit.
Printing is performed by projecting the ears from the wire guides
In the wire dot print head, a first engagement groove with which the preceding base plate is engaged;
A second engagement groove with which a rear-side top plate is engaged;
And a through-hole for passing the printing wire on the rear side.
The print head units are connected to each other by a joint member.
A wire dot print head, characterized in that: 4. The printing wire is connected to the joint member.
A guide part for guiding and supporting is provided.
3. The wire dot print head according to 3. 5. The joint member is made of a material having high thermal conductivity.
4. The wire dock according to claim 3, wherein
Print head.