JPS63218368A - Hammer drive mechanism for dot line printer - Google Patents

Abstract

PURPOSE:To make a hammer drive mechanism applicable onto a high speed dot printer which does not produce much heat, by making slits approximately in parallel with the direction of magnetic flux flowing through a core, thereby reducing eddy current occurring in the core when a hammer is driven and improving energy efficiency of a hammer drive mechanism. CONSTITUTION:A leaf spring is normally attracted to a core 5 by magnetic force of a permanent magnet 1 and bent. When current is fed to a degaussing coil 7, as required, magnetic force of the permanent magnet is cancelled to release the leaf spring 6 so as to move a print pin 9 by the energy stored in the leaf spring 6 thus printing onto a paper through an ink ribbon. When there are slits 4 in the direction approximately in parallel with the magnetic flux flowing through the core 5, electrical resistance is increased by the slits made in the path of eddy current upon supply of current to the degaussing coil 7 thereby eddy current is reduced. The permanent magnet 1 is sandwitched by a yoke 2 and a base yoke 3 to which the core 5 having slits 4 approximately in parallel with flux flowing from the permanent magnet 1 is welded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to dot line printers, and more particularly to hammer drive mechanisms.

[Conventional technology]

A conventional printer drive mechanism of this type of dot line printer will be explained with reference to the drawings. FIG. 3 is a partially sectional plan view of a conventional dot line printer, and FIG. 3(B) is a side sectional view. The permanent magnet 21 is sandwiched between a yoke 22 and a base yoke 23, and a core 25 around which a degaussing coil 24 is wound is connected to the base yoke 23 by a screw 26. On the other hand, one end of the leaf spring 27 is fixed between the yoke 22 and the clamp plate 28, and a printing pin 29 is connected to the free end of the leaf spring 27.

Normally, the plate spring 27 is attracted to the core 25 by the magnetic force of the permanent magnet 21, and the plate spring 27 is bent as shown in FIG. 3-b. When a current is applied to the degaussing coil 24 as necessary, the magnetic force of the permanent magnet 21 is canceled and the leaf spring 27 is released, and the energy stored in the leaf spring 27 causes the printing pin 29 to move and remove paper (not shown). Dots are printed on the paper using an ink ribbon.

[Problem that the invention seeks to solve]

The hammer drive mechanism of the conventional dot line printer described above is extremely energy inefficient, as eddy currents are generated in the core when current is passed through the degaussing coil wrapped around the core to release the leaf spring. As dot line printers increase in speed, heat generation from the hammer drive mechanism has been one of the problems that prevents the printer from increasing in speed.

[Means for solving problems]

The hammer drive mechanism of the dot line printer of the present invention includes a leaf spring engaged with a printing bottle, a core around which a degaussing coil is wound, a yoke that forms a magnetic path together with the core, and a yoke interposed in the middle of the magnetic path. A hammer drive mechanism of a dot line printer, which has a permanent magnet and drives the leaf spring attracted to the core, includes a core having at least one or more slits substantially parallel to a direction in which magnetic flux flows, and a pace yoke. are joined to form a yoke.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

Referring to FIG. 1, in one embodiment of the present invention, a permanent magnet l is sandwiched between a yoke 2 and a pace yoke 3;
A core 5 in which a slit 4 is provided substantially parallel to the direction in which the magnetic flux generated from the permanent magnet 1 flows is welded to the pace yoke 3.

(The joining method does not matter.) A demagnetizing coil 7 for releasing a leaf spring 6, which will be described later, is wound around this core 5. - One end of the force plate spring 6 is fixed between the yoke 2 and the clamp plate 8, and a printing pin 9 is connected to the free end of the plate spring 6.

Next, the operation will be explained. Normally, the leaf spring is attracted to the core 5 by the magnetic force of the permanent magnet 1, and the leaf spring 6 is deflected as shown in FIG. Degaussing coil 7 if necessary
When a current is applied to , the magnetic force of the permanent magnet is canceled and the leaf spring 6
is released, and the printing bottle 9 is driven by the energy stored in the leaf spring 6, printing dots on a sheet of paper (not shown) via an ink ribbon. By the way, if the core 5 has the slit 4 that is substantially parallel to the direction in which the magnetic flux flows as in the present invention, when a current is passed through the degaussing coil 7, stains may occur due to the presence of the slit in the path through which the eddy current flows. Since the resistance increases, the eddy current decreases.

Referring to FIG. 2, another embodiment of the present invention differs from the embodiment shown in FIG. 1 in that a pace yoke 13 and a core 15 having a slit 14 are connected using a screw lO.

〔Effect of the invention〕

As explained above, the present invention reduces the eddy current generated in the core when the hammer is driven by providing the core with slits that are substantially parallel to the direction of magnetic flux flow, thereby increasing the energy efficiency of the hammer drive mechanism and generating less heat. The present invention provides a hammer drive mechanism compatible with high-speed dot line printers.

[Brief explanation of the drawing]

Fig. 1(A) is a plan view (partially sectional) showing one embodiment of the present invention, Fig. 1(B) is a sectional view of the same side, and Fig. 2 shows another embodiment of the present invention. FIG. 3(4) is a plan (partially sectional) view of a conventional hammer drive mechanism, and FIG. 3(B) is a sectional side view thereof. 1...Permanent magnet, 2...Yoke, 3.
...Pace yoke, 4...Slit, 5
... Core, 6 ... Leaf spring, 7- ...
... Demagnetizing coil, 8 ... Clamp plate, 9
...Print bottle, 10...Screw, 11.
...Permanent magnet, 12...Yoke, 13.
...Pace yoke, 14...Slit,
15... Core, 16... Leaf spring, 17
... Degaussing coil, 18 ... Clamp plate, 19 ... Printing bottle, 21 ...
Permanent magnet, 22... Yoke, 23...
Pace yoke, 24... Demagnetizing coil, 25...
... Core, 26 ... Screw, 27 ...
・Plate spring, 28... Clamp plate, 29.
...Printing bottle. Agent Accountant Uchihara ('・-1 Eternal Evil 2 Yoke 3 Base Yaw 7 4, Susonto (B) Figure 1 10: Screw 11: Nagasu Ishimori Ishi 12: Yoke J3: Base 3-2 14; λ Sonto 15゛Core 16; Square spring 17: 5 coils of stone raised 18 2 Clamp plate 19 ゛U-shaped pin 7 1g Fig. 2 □ ?5 38. Fig. 3 Base yoke 24, stone shaving coil 25゛ core 26 Screw 27: Opposite side 28: Classical grade 2q: Printing bottle (2 Otsuz

Claims (1)

[Claims] It has a leaf spring engaged with a printing pin, a core around which a degaussing coil is wound, a yoke that forms a magnetic path together with the core, and a permanent magnet interposed in the middle of the magnetic path, and is attracted to the core. The hammer drive mechanism of the dot line printer that drives the leaf spring described above is characterized in that the yoke is constructed by joining a base yoke to a core having at least one or more slits substantially parallel to the direction in which magnetic flux flows. Hammer drive mechanism of dot line printer.