JPS5945167A - Print head for dot printer - Google Patents

Abstract

PURPOSE:To achieve a smaller print head for high speed response by operating the printing wire at both ends of an armature oscillating with the central piece of an E-shaped yoke as the fulcrum to reduce the space of electromagnets with the common use of the yoke therefor. CONSTITUTION:With the excitation of a coil 12a, an armature 13 is attracted to one right piece 11c of a roughly E-shaped yoke 11 while a printing wire 15a contacting the right end 13c thereof is operated to strike a dot at the free end of the printing wire 15. The coil 12a is demagnetized to move the print head in the direction of the arrow X by a pitch P. In the mean time, likewise an opposite coil 12b is excited to force down the printing wire 15b striking a dot. When the coil 12b is excited to attract the left piece 13b of the armature to a yoke piece 11a, the right piece 13b' thereof on the opposite side is separated forcibly. With such an arrangement, the common use of the yoke for the electromagnets is made possible thereby enabling the miniatulization of the print head for a high speed performance.

Description

Detailed Description of the Invention (Technical Field) The present invention uses an electromagnet to selectively attract and drive a plurality of armatures each connected to a printing wire, so that the printing wire is moved to a driving position to print characters, symbols, etc. The present invention relates to a print head for a wire dot printer which is capable of printing, and particularly relates to a print head in which marking portions of printing wires are arranged in two rows.

(Prior Art) A print head of a conventional wire dot printer will be explained with reference to FIGS. 1 and 2. 1 is a yoke with 2 pieces 1 on a common disk
A plurality of sets of rod-shaped yoke pieces 1a and lb are integrally formed in the circumferential direction. 2 is one yoke piece 1b of the yoke.
It is a coil equipped with. 3 is a set of yoke pieces 1a;
He is an amateur placed astride the 'lb. The base end 3a is pressed against the armature surface of the one yoke piece 1a and serves as a fulcrum, and the intermediate portion 3b has a flapper structure that approaches and separates from the armature surface of the other yoke piece 1b.
It has a tapered shape extending from b to the free end 3C (see FIG. 2), and the free end 3C is arranged opposite to the terminal end of the printing wire 6. Reference numeral 4 denotes an armature fixing spring which elastically presses and holds the proximal end 3a of the armature 3 against the armature surface of one of the yoke pieces 1a. 5 is a return spring and print wire 6
is constantly pulled up and separated from the armature surface of the yoke piece 1b against the pressing force of the fixed spring 4 on the armature. 6
is a printing wire that is always straight, but is inserted with a certain radius of curvature into a guide body 9, which will be described later. Reference numeral 7 denotes an abutting body integrated with the printing wire and abuts against the free end 3c of the armature 3. Reference numeral 8 denotes a cover of the optical print head, which regulates the position of the fixed spring 4 and the free end 3C of the armature 3. 9
is a guide body for the printing wire 6 so that the printing wire 6 is converged toward the tip 9a, and there is also a guide body for the printing wire 6.
There are holes in the rows in a staggered pattern. Further, the guide body supports one end of the return spring 5 and is fixed to the yoke l. As shown in FIG. 2, the optical print head has a plurality of print wires and electromagnetic devices arranged in pairs in the circumferential direction.

The operation of the print head of a wire dot printer as described above is such that by exciting the coil 2, the armature 3 is attracted to the yoke piece 1b using its base end 3a as a fulcrum, and at the same time, the free end 3C resists the return spring 5. The printing wire 6 integrated with the abutting body 7 is pushed down and a dot is printed.

On the other hand, a plurality of electromagnets arranged in the circumferential direction operate predetermined printing wires 6 in the same way as described above in response to commands from the outside.

However, since the tip of the guide body has two rows of staggered holes, the dots are first stamped by the operation of the corresponding electromagnet of the printing wire inserted into the holes in the first row A. Subsequently, after the print head is shifted by the pitch P in the direction of the arrow X, the print wire inserted into the second row hole prints dots corresponding to the other electromagnets.

This operation is repeated to display a predetermined character or symbol.

As described above, in the conventional example, electromagnets corresponding to the number of printing wires are required, and in particular, in the case of a medium-dot printer that displays Chinese characters, a large number of printing wires must be configured. As a result, the print head inevitably had to become larger. Furthermore, dot printers are required to have high-speed response, but with the conventional electromagnetic structure, the armature is heavy due to its natural return due to the return spring, so it is difficult to increase the return speed due to the influence of the armature's mass. There was a problem with responsiveness.

(Purpose) The present invention has been made to solve the above problems, and its purpose is to operate the printing wire at both ends of the armature that swings around the center piece of the approximately E-shaped yoke. By doing so, it is possible to use a common yoke, thereby reducing the electromagnet space and downsizing the print head as a whole, and also providing a print head with good high-speed response by increasing the return speed of the armature.

(Example) Figures 3, 4, and 5 are shown below as examples of the present invention.
The diagram will be explained. 11 is a substantially E-shaped yoke;
The ends of the left and right side pieces 11a and IIC serve as polarized surfaces, and the center piece 11b serves as a fulcrum for an armature to be described later. 12
are coils wound around the left and right pieces 11a, IIC, of the yoke.

13 is an armature that is magnetically coupled to the central piece 11b of the substantially E-shaped yoke 11 and is swingably supported; a position 1.3b located a predetermined distance away from the central portion 13a;
Further, left and right end portions 13c are in contact with and separated from both liquid electrode surfaces of the E-shaped yoke IJ at 13b.

13C' faces a contacting body 16Φ which is integrated with the printing wire 15. 14 is the central portion 13a of the armature;
This is a fixed spring that elastically presses and supports.

Reference numeral 15 denotes a printing wire whose base end is fixed integrally with the abutting body 16, contacts the left and right ends 13C and 13c' of the armature, and moves along with the rocking movement, and the free end is a dot marking part for optical printing. The left and right printing wires 15a are normally set on a straight line and have a certain radius of curvature in the assembled state.
, 15b form a pair of guide bodies 1, each of which will be described later.
It is inserted into hole 9. 17 is a return spring that constantly pulls up the printing wire 15. Reference numeral 18 is a case in which each of the above components is stored in m blocks. In the case, the printing wire 15 is guided and restrained, and the return spring 1v and the fixing spring 14.
The position of the approximately E-shaped yoke 11 is regulated. FIG. 5 shows a state in which a large number of printing wire blocks are housed in one set. Reference numeral 19 denotes a guide body at the tip of the printing wire 15. As shown in FIG. 4, staggered holes are provided in two rows. The printing wires inserted in row B and forming other pairs are similarly inserted in the first row A and second row B in the stacked order.

To explain the operation of the configuration of the present invention as described above,
First, in a non-excited state, a gap G is secured in the armature 3. Now, by energizing the coil 12a, the armature 13 is activated on one right side 1 of the approximately E-shaped yoke 11.
1C, and at the same time the right end 13C of the armature 13
' is operated. A dot is then stamped at the free end of the printing wire 15. Thereafter, the coil 12a is demagnetized and the printing head is moved in the direction of the arrow X by a pitch P, during which time the coil 12b on the opposite side is energized and the printing wire 15b is pressed down in the same manner as described above to print dots.

When the left bank 1.3b of the amateur is attracted to the yoke piece 11a by energizing the coil 12b in this way, the right bank 13G of the armature on the opposite side is forcibly separated even if the return due to de-excitation of the coil 12a is not completed. As a result, the return speed of the print wire 15a becomes faster, that is, the print head of the dot printer can be operated at higher speed. Additionally, a pair of coils 12a.

12b is controlled by an external operation, but both coils are never excited at the same time, and one is always demagnetized before the other is excited.

(Effects) As described above, in the print head of a wire dot printer, the present invention includes a substantially E-shaped yoke having a center piece and left and right side pieces, left and right coils installed on the left and right side pieces, and the center piece. an armature which is magnetically coupled to and swingably supported, and whose left and right end surfaces are alternately adsorbed and detached from the left and right side pieces; Since the structure is made up of left and right printing wires that are driven by No electromagnet is required, and the entire print head can be made extremely compact.Furthermore, if the right side of the swingable armature is attracted, the opposite left side is forcibly separated, so the driven print wire is This has the effect of not being subjected to the load of amateurs, increasing the return speed, and providing a print head with good high-speed performance.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing a conventional example of a print head of a dot printer, and Fig. 2 is a top view showing a similar conventional example. 3 is a sectional view showing an embodiment of the present invention, FIG. 4 is an enlarged view of a hole in a guide body of a print head of the present invention, and FIG. 5 is an external perspective view of the present invention. Approximately E-shaped yoke: 11 Center piece of approximately E-shaped yoke: 11b Right side of approximately E-shaped yoke: 11C Left side of approximately E-shaped yoke: 113 Amateur: 13 Right end surface of amateur: 13 C'Amateur's Left end surface: 130 Printing wire = 15 Right printing wire = 15a Left printing wire: 15b Patent applicant Toshimaru Takemoto, patent attorney representing Matsushita Electric Works Co., Ltd. (and 2 others) Figure 1 Figure 3

Claims (1)

[Claims] A generally E-shaped yoke having a center piece and left and right side pieces, left and right coils installed on the left and right side pieces, magnetically coupled to the center piece and swingably supported, and with its left and right end surfaces connected to the left and right side pieces. A print head 6 of a dot printer consisting of an armature that alternately adsorbs and detaches from the left and right side pieces, and left and right printing wires whose left and right end surfaces and their base ends face each other and are driven by the swinging motion of the armature.