JPS6058873A - Magnetic powder supplying mechanism for printing apparatus - Google Patents

Abstract

PURPOSE:To supply a predetermined amount of a magnetic powder to a printing position, by a method wherein a magnetic powder is supplied to a cylindrical surface of a cylindrical permanent magnet, and the permanent magnet is fitted to a rotary body so that the cylindrical surface is passed through a printing position faced to a magnetic head. CONSTITUTION:A predetermined one of cartridges 8 is positioned at an upper part by rotating a casing 7 in the direction of an arrow, and an opening part 9 of the cartridge 8 is matched to an upper opening of the casing 7. The cylindrical permanent magnet 10 is rotated in the direction of an arrow, a magnetic powder layer having a predetermined thickness is provided on the surface of the magnet 10 at the printing position faced to the magnetic head 1, and printed density is maintained to be constant.

Description

[Detailed Description of the Invention] [Technical Field] The present invention provides a magnetic head that attracts a mixture of magnetic powder and toner (hereinafter simply referred to as "magnetic powder") through a printing paper. The present invention relates to a printing device that performs printing, and particularly to a mechanism that supplies magnetic powder to a printing position.

[Prior art]

Conventionally, in order to attract magnetic powder by electromagnetic means and print desired characters, symbols, figures, etc., on plain paper (hereinafter simply referred to as "printing"), magnetic powder was used as shown in Figure 1. A magnetic head 1 such as an electromagnet whose size can be adjusted is positioned on one side (usually the top side) of the printing paper 2, and magnetic powder 3 is placed on the other side (usually the bottom side) of the printing paper 2. A permanent magnet 4 is placed in the magnetic powder so that one end thereof faces the head 1, and while the printing paper 2 is run relative to the head 1, the stored magnetic powder 3, and the permanent magnet 4. By inputting an appropriate control signal to the head 1, the magnetic force can be adjusted as appropriate. Usually, a constant magnetic force is turned on,
OFF control is performed), this attracts the magnetic powder attached to the end of the permanent magnet 4 and deposits it on the printing paper,
The toner in the magnetic powder is heated and melted to be fixed on the printing paper 2 by a conventional method, and the magnetic powder is recovered. However, in this method, the permanent magnet 4
When the magnetic powder 5 is attracted from the tip of the magnetic powder 5 and attached to the printing paper 2, a gap 6 is formed after the magnetic powder 5 leaves. should flow to fill the void 6 and prepare for the next attraction of the magnetic material by Henodoe, but since the magnetic material 3 does not have high fluidity, the amount and speed of supply of the magnetic powder 3 to the void 6 is limited. This was insufficient, and as a result, the print density was not constant, resulting in missing prints, and it was difficult to improve the printing speed.

[Object of the present invention]

SUMMARY OF THE INVENTION In view of the above-mentioned prior art, an object of the present invention is to provide a magnetic powder supply mechanism that can always supply a fixed amount of magnetic powder to a printing position.

[Example of the present invention]

FIG. 2 is a partially sectional side view showing an embodiment of the magnetic powder supply mechanism according to the present invention. A cylindrical case 7 is arranged on the lower surface side of the printing paper 2 held horizontally at a position facing the magnetic head 1 on the upper surface side.

The upper part of the case 7 is open. Four magnetic powder cartridges 8 are housed in the case 7. The magnetic powder 3 is housed inside the cartridge 8, and an opening 9 is formed in the cylindrical outer surface facing the inner surface of the case 7, and the cylindrical shape of the case 27 is formed in the opening. A cylindrical permanent magnet 10 having a rotation axis parallel to the axial direction of the magnet is provided so as to be rotatable. There is a slight gap between the permanent magnet 10 and the cartridge 8, and the magnetic powder present in this gap is affected by the attractive force of the permanent magnet 10. This gap is also such that a sufficient amount of magnetic powder layer for printing can pass through.

Each cartridge 8 is arranged rotationally symmetrically, and while maintaining this relative positional relationship, the cartridge 8 is rotated around its cylindrical central axis within the case 7 by an appropriate driving means (not shown) at an arbitrary angle. It can be rotated. A permanent magnet 11 having a larger attractive force than the permanent magnet 10 is arranged below the case 7.

Next, the operation of the supply mechanism of this embodiment will be explained.

The head 1, case 7, and permanent magnet 11 are made to travel in the direction of the arrow while maintaining their relative positional relationship, and the printing paper 2 remains stationary. In the cartridge 8 located at the lowest position in the case 7, the magnetic powder 3 inside the cartridge 8 is attracted downward by the attractive force of the strong permanent magnet 11, that is, the cylindrical permanent magnet 100.
They are gathered nearby and placed under its influence. By rotating all the cartridges 8 in the direction of the arrow, a predetermined cartridge 8 is positioned at the top, and its opening 9 is aligned with the upper opening of the case 7. When the cylindrical permanent magnet 10 is rotated in the direction of the arrow in this arrangement, the surface of the permanent magnet 10 has a magnetic field with a constant thickness corresponding to the gap between the magnet 10 and the cartridge 8 at the printing position facing the head 1. Powder layer is published 4.
By appropriately controlling the magnetic powder 1 at the appropriate time, the magnetic powder 3 at the printing position on the surface of the permanent magnet 1o is attracted so as to form a desired pattern on the printing paper 2. The magnetic powder 3 on the permanent magnet lo that was not attracted by the head 1 returns to the cartridge 8 again. Here, by adjusting the rotation speed of the permanent magnet 10, the permanent magnet 1 at the printing position can be
o In the magnetic powder supply mechanism of this embodiment, each cartridge 8
contains magnetic powder 3 containing toner of different colors,
Cartridge 8 for the desired color up to the appropriate printing position
When the cartridges 8 are rotated, color printing becomes possible.Of course, each cartridge 8 can be replaced independently. Furthermore, in the cartridge 8 at the printing position, as the permanent magnet 10 rotates, the magnetic powder 3 may gradually escape from the influence of the permanent magnet 1o and fall downward due to its movement. By rotating all the cartridges 8 once in the case 7, the magnetic powder 3 is again collected near the permanent magnet 10 by the strong attraction force of the permanent magnet 11.

FIG. 3 is a partially sectional side view showing another embodiment of the magnetic powder supply mechanism according to the present invention. In this embodiment, the cartridge 8 is rotatable in the direction of the arrow within a cylindrical case (not shown), and the cylindrical permanent magnet 10i is driven to rotate in the direction of the arrow.

The printing paper 2 is arranged vertically. Other points are similar to the embodiment shown in FIG. 2, but in the case of this fourth embodiment, there is no strong permanent magnet 11 corresponding to i11 in FIG. When the cartridge 8 is positioned at the lowest position due to its rotational movement, the magnetic powder 3 in the cartridge 8 is collected by gravity below, that is, near the permanent magnet 30, and is brought under its influence. The cartridge 8 is further rotated from this position, and the permanent magnet 10 is rotated to the printing position, that is, the horizontal position, and printing is performed.

In this embodiment as well, color printing is possible as in the embodiment shown in FIG. 2, and the cartridge 8 is replaceable. Magnetic powder 3 can be collected.

[Effects of the present invention]

According to the magnetic powder supply mechanism of the present invention as described above, a constant amount of magnetic powder is always supplied to the printing position when the magnetic head moves relative to the printing paper during printing, so that the printing density can be kept constant. It is possible to maintain high printing speed, and it can also sufficiently cope with the increase in printing speed.

[Brief explanation of the drawing]

FIG. 1 is a side view of a conventional printing device, and FIGS. 2 and 3 are partially sectional side views of a printing device having a feeding mechanism according to the present invention. 1: Magnetic head, 2: Print paper, 3: Magnetic powder, 4: Permanent magnet, 7: Case, 8: Cartridge, 9: Opening part,
10: Cylindrical permanent magnet, 11: Permanent magnet.

Claims (2)

[Claims] (1) In a printing device that performs reverse printing by attracting magnetic powder through printing paper using a magnetic head, magnetic powder is supplied to the cylindrical surface of a cylindrical permanent magnet, and the permanent magnet A magnetic powder supply mechanism for a printing device, characterized in that the magnetic powder supply mechanism is rotated so as to pass through a printing position facing the head. (2) A plurality of cartridges for magnetic powder are housed in the case, and each of the cartridges can be replaced independently. Each cartridge is provided with an opening at a position that becomes the outer periphery during rotational movement, and a cylindrical permanent magnet is rotatably mounted in the opening with a predetermined gap. The magnetic powder supply mechanism of item 1.