JPS5991069A - Release type dot printer head - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Part of the Invention!l!t) This invention relates to a release type dot printer head.

[Technical background of the invention and its problems]

Conventionally, as shown in Fig. 1, an electromagnetic coil (3) is attached to a plurality of cores (2) arranged in a disk-shaped yoke (1), and a disk-shaped permanent magnet is attached to the yoke (1). (4) Fully fixed, then armature (6) with needle (5) fixed.
) is held by a leaf spring (7), the V armature (6) is attracted to the core (2) by the magnetic flux of the permanent magnet (4), and the permanent magnet (4) is There is a release type dot printer head that cancels the magnetic flux and moves the armature (6) and the armature (5) in the printing direction by the force of a leaf spring (7).

However, in such a device, adjacent cores (2) are magnetically coupled via the yoke (1), causing magnetic interference. In other words, as shown in Figure 2+a), the specific (
When the electromagnetic coil (3) in the center) is fully excited, the permanent magnet (4
) is the magnetic flux of yoke (1)? t-trace adjacent cores (2)
It is easy to cancel the magnetic flux of the permanent magnet (4) in the central core (2) by flowing 1t, but as shown in Figure 2 (all 'N'
, When the 4M coil (3) is excited, the magnetic flux of the permanent magnet (4) does not flow to the adjacent core (2), making it difficult to cancel the magnetic flux.

Therefore, the driving conditions differ depending on the number of IF electromagnetic coils 3) to be excited.

That is, as the number of excited electromagnetic coils (3) increases, the opening/closing ampere turns increase.

If the printing speed is kept constant and the printing speed is CFJJ, the power consumption will increase, and there is a drawback that the printing speed cannot be increased by 7F.

In addition, as shown in Fig. 4, a ring-shaped permanent magnet (8)
k't'ii, magnetic coils (some books have magnetic coils positioned around the co-coils and fixed to the yoke (1), but each core (2) is connected via the yoke (1) mechanically. Therefore, the above-mentioned drawbacks cannot be solved.Furthermore, since the permanent magnet (8) is fixed to the yoke (1) so as to surround the core (2), the permanent magnet (8), the yoke (1), and the core (2) ,
The disadvantage is that the magnetic path leading to the armature (6) is too long.

For this reason, as shown in Figures 5 and 6,
A donut-shaped permanent magnet 00 is fixed in the housing (9), and the permanent magnets 0 (a plurality of cores α1 joined to one side of the fist) are arranged in an ant-like shape, and these cores (
11) with a permanent magnet (pin a2 parallel to the joining surface to 1(e)
and connect the electromagnetic coil (3)'t to these pins a2.
In addition, there is a device in which a plurality of armatures Oj having needles (5) are biased in the printing direction by leaf springs OIo each fixed in a cross shape to a block α4.

The operation is such that the magnetic flux of the permanent magnet Q[J is extinguished by the excitation action of the electromagnetic coil (3), and the leaf spring 0υQG is moved in the direction of printing αil. In this case, each core α
Since η are independent, the reluctance for adjacent cores αυ is greater than that shown in FIGS. 1 and 3. However, since the area of the opposing surface 0η with respect to the adjacent core aυ is large, the magnetic flux passes through the air to the adjacent core 0.
It leaks. In addition, the core 0υ is a few plane O parallel to the pin 02
F! Since j is connected to the permanent magnet αIK, the permanent magnet O
o, the magnetic path from core 0υ to armature (1, 11) becomes longer, and magnetic flux flows in the air on this surface as well, causing magnetic interference to not be reliably prevented.Furthermore,
Because the surface M and the end surface of pin αa (armature suction surface) are perpendicular to each other, it is difficult to process parts, and pin aa is also
It is difficult to attach the electromagnetic coil (3) because it faces the direction of the central force rather than the opening surface of the housing (9).

[Purpose of the invention]

The present invention has been made in view of the above-mentioned points, and an object thereof is to provide a release type dot printer head that can prevent magnetic interference.

[Summary of the Invention J This invention involves fixing independent l-shaped cores at intervals to a permanent magnet facing the armature, and also increasing the joint surface of these irons to the permanent magnet and increasing the distance from the permanent magnet. The cross-sectional area of the metal is made small, thereby preventing leakage of magnetic flux to adjacent cores.7 Furthermore, the core is fixed to the permanent magnet by being positioned on the surface facing the armature, thereby preventing the magnetic flux from the permanent magnet to the armature. In order to reduce the path length and thus prevent magnetic interference between adjacent cores, the attachment of the core to the permanent magnet is wider towards the interface with the permanent magnet, which reduces the magnetic flux. It is constructed to increase the suction force of the armature by increasing the density.

[Embodiment J of the Invention An embodiment of the invention will be described with reference to FIGS. 7 to 10. KJ is a yoke with fin QυtW, and this yoke has a 3%5iF fin from the viewpoint of dimensional accuracy, magnetic efficiency, and economical efficiency.
It is made of a sintered alloy of e.

A donut-shaped permanent magnet Q is fixed to the bottom of this yoke, and a plurality of cores ψ are fixed at intervals to the core holding surface (C) of the permanent magnet e, which faces the armature (C). There is. These cores ψ are formed from a sintered alloy of 2.5 to 3.5% 5iFe in consideration of overcurrent loss and saturation magnetic flux density. These cores (c) have an attachment part (c) to the core holding surface (Q4) and a columnar protrusion (9) to which the electromagnetic coil (h) is mounted, and the attachment part (c) is attached to the core holding surface (h) when viewed from the side. ) is defined by a trapezoidal shape in which the width of the bonding surface is maximum and becomes narrower as it goes away from the core holding surface (c), and the distance (S) between adjacent cores (c)? L-Secure;
In addition, from the center line of the yoke, the yoke is formed in a 1-shaped shape, with the width on the outer periphery being wide and the width on the inner periphery being narrower. It crystallizes the magnetic flux density of magnet Q4. There are multiple plunger yokes cq11 between the yoke holder and the guide boulder (c).
Is that true? I'm standing there. Armature (c) Plunger (10i) fitted to the phantom plunger yoke (arm) (molded from plastic with 3 parts and needle G part buried, fulcrum 0 connected to plunger yoke ζ1 on the - side) are formed protrudingly.These armatures are urged in the printing direction by a spring 0.The kite boulder (c) has a guide rib 09 that guides the movement of the armature Kl and a needle guide (1()). It is set up.

In such a construction, the armature-shaped plunger (the plunger is attracted to the core by the permanent magnet Q2, but the WJ, (if coil ell)'j:: by energizing it, The magnetic flux of the armature μ and the spring (◆
It moves in the printing direction as the center. Each core Qj has an interval (8
They are arranged 1'r apart, and the width becomes narrower as they move away from the permanent magnet (A), so the cores ψi in contact with each other are 1liilj.
The distance between is wide. Therefore, it is possible to eliminate leakage of magnetic flux between the cores (c). Since the permanent magnet Q2 is joined to the core (C) with the surface ♀ facing the armature (C), the length of the magnetic path from the permanent magnet (A) to the armature body is short, and the 6 fluxes are connected to the space 'IL'. Mi: Prevents leakage of magnetic flux due to leakage. therefore,
It is possible to prevent an increase in power consumption due to magnetic interference and increase printing speed. Since the columnar protrusion 9 of the core (c) also faces toward the open end of the yoke with respect to the permanent magnet Q2, assembly of the electromagnetic coil CI) is easy. In order to prevent magnetic interference, the cores (IE) are spaced apart, but the joint surface with the core holding surface (IE) is large,
By increasing the magnetic flux density of the permanent magnet Q, the armature (c)
It is possible to suction quickly and with strong suction force.

Furthermore, by using permanent magnets (made of rare earth cobalt), the linearity of the B-H curve (characteristic showing the relationship between magnetic flux density and magnetomotive force) is improved in the fourth quadrant, and the demagnetizing E
The magnetic force does not decrease even when the magnetic field is strong.

(Effects of the Invention) As described above, this invention has J number of cores arranged at dovetail intervals and fixed to a permanent magnet, and furthermore, by reducing the cross-sectional area of the cores as it becomes 14+ from the total permanent magnet,
The conditions for maintaining a high magnetic flux density of permanent cores are met, while being able to prevent leakage of magnetic flux between adjacent cores.
Furthermore, by fixing the core to the permanent magnet with the surface facing the armature, the length of the magnetic path from the permanent magnet to the armature can be shortened, and magnetic interference caused by the flow of the magnet 14 during production can also be prevented. This has the effect of reducing power consumption and increasing printing speed.

[Brief explanation of drawings]

Figure 1 is a partially cutaway side view showing a conventional example;
The figure is an explanatory diagram showing the state in which the magnetic flux leaks, Figure 3 is a graph showing the relationship between the excited city, the number of magnetic coils, and the open ampere turns, and Figure 4 is a part of the second conventional example. FIG. 5 is a side view with a part cut away showing the third conventional example, FIG. 6 is an exploded view showing the relationship between the permanent magnet, core and armature, and FIG. Figure or first
0 shows one embodiment of the present invention, FIG. 7 is a side view with a part cut away, FIG. 8 is a plan view showing a part of the yoke, FIG. 9 is a perspective view of the core, and FIG. The figure is a side 1lIi diagram showing an expanded state of the arrangement of the cores. 22... Permanent magnet, 23... Armature, 24...
... Core holding surface, 25 ... Core, 26 ... Mounting surface,
27... Electromagnetic coil, 28... Columnar protrusion, 32...
・Needle, 34...Spring Applicant: Tokyo Electric Co., Ltd. Kazuo Wakasugi Tono 1 Tenant Indication Patent Application No. 1983-201430 2 Name of the invention Release type dot printer head; *, Drawing 7 Please refer to the attached sheet of contents of the sleeve IL! Amendment No. 57-201430 Regarding this application, the description and drawings in the specification are amended as below. Note 1, “Overcurrent loss” on page 6, line 10 of Specification 1 is changed to “
Correct for eddy current loss. 2. Correct Figure 4 as shown in the attached sheet.

Claims (1)

[Scope of Claims] 1. A plurality of armatures with needles connected to each other are biased toward the printing force direction by springs and arranged in a freely undulating manner, and the core holding surface facing the armatures is arranged in the same direction.
The permanent magnet formed in Thi is used for i? A plurality of cores are provided, each of which has a maximum Il product and whose cross-sectional area gradually decreases as it moves away from the core holding surface, and a columnar protrusion that holds an electromagnetic coil and is spaced ΔL from this several-part part. A release type dot printer head characterized in that these cores are arranged and fixed to the core holding surface at intervals from each other. 2. ψ11 area gi' of Patent H111, characterized in that the width of the first part of the core is greatly increased from the center of the permanent magnet to the outer circumference by 21-, and the open type described in item 1 dot printer head.