JPS6315151B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an opening in a part of the bump magnet, and creates a head between the opening and the liquid level of the ink tank so that the opening has a negative pressure head. The present invention relates to a magnetic ink recording device that performs recording by forming a flow path and forming an appropriate bulge on the tip of a stylus and causing the stylus to fly.

Magnetic ink that reliably forms a predetermined flow path without applying excessive negative pressure head when filling the flow path from the ink tank to the opening with magnetic ink to create a negative pressure head at the opening. The aim is to provide a recording device.

A conventional magnetic ink recording device will be explained using FIGS. 1 to 3. Reference numeral 1 denotes a stylus made of a magnetic material, which is regularly arranged and pasted on a base 2. Reference numeral 3 denotes an uplifting magnet, which is composed of two magnets, one of which is pasted on the stylus, and the other is arranged to form an opening between it and the one uplifting magnet. Reference numeral 4 denotes an ink supply path, one end of which communicates with the opening, and the other end of which leads to an ink tank 5.
It is familiar to In addition, a supply pump 6 is installed in a part of the supply path.
is provided. When the feed pump 6 is stopped, fluid can flow freely through it, such as in an axial flow pump. A pipe 7 supplies magnetic ink from a main tank (not shown) to the ink tank 5, and a pump 8 is provided in the middle of the pipe. 9 is a collection pipe leading to the main tank, and the magnetic ink supplied from the supply pipe 7 is collected into the main tank from the collection pipe 8.
The magnetic ink liquid level in the ink tank 5 is kept constant at regular intervals.

In such a device, when the supply pump 6 supplies magnetic ink to the supply path and the opening of the bump magnet 3 to fill the magnetic ink, a force to hold the magnetic ink in the opening works, and the supply pump 6 Even if the magnetic ink is stopped, the supply path 4 and the opening remain filled with magnetic ink. At this time, a head difference of H is formed between the opening and the liquid level of the ink tank, and an appropriate protuberance of height a is formed at the tip of the stylus as shown in FIG. There is. Further, the amount of magnetic ink consumed during recording is automatically supplied through the supply path 4 and the opening (without operating the supply pump), allowing continuous recording. However, as shown in Figure 2, the pressure head of negative pressure that forms an appropriate bulge (set value H within the range of H ₁ to H ₂ )
There is a small difference between this and the limit value _H3 of the pressure head of the negative pressure that can be withstood at the opening of the uplift magnet 3 (see FIG. 3). Therefore, when the supply pump 6 fills the supply path 4 and the opening of the uplift magnet 3 with magnetic ink and stops the supply pump 6 at _T1 as shown in FIG. The pressure head acting on the opening is from H ₄ to the negative pressure head H
Changes to At this time, the pressure head that momentarily acts on the opening of the uplift magnet 3 changes along the attenuation curve shown in FIG. 3, and finally reaches the set value H, but the attenuation amplitude is large and T The limit value _H3 was exceeded at position ₂ , and it was not possible to draw in air and ensure that the opening had a negative pressure head of H.

The present invention attempts to solve such conventional problems and reliably apply a negative pressure head to the opening.

An embodiment of the present invention will be described in detail below using FIGS. 4 to 6.

Numeral 10 is a multi-stylus made of magnetic material, which is regularly arranged and pasted on a base 11. 1
2 is a bump magnet, 13 is an auxiliary magnet, and these 2
The multi-stylus 10 is magnetized by two magnets, and the magnetic ink 14 is attached to the multi-stylus 10. Further, the bump magnet 12 and the auxiliary magnet 13 are arranged to form the opening A, and the magnetic ink 14 is held in the opening A with a large force. Reference numeral 15 denotes a supply path, one end of which communicates with an opening A formed by the uplift magnet 12 and the auxiliary magnet 13, and the other end connected to an ink tank 16. Further, the magnetic ink 14 is supplied to the supply path 15 from the ink tank 16.
and a supply pump 17 for filling the opening A. The supply pump 17 is configured to supply the magnetic ink 14 in the direction of the arrow A while in operation, and to allow the magnetic ink 14 to freely flow therein while the supply pump 17 is stopped. Pipes 18 and 19 circulate the magnetic ink 14 between the ink tank 16 and a main tank (not shown). 18 is a supply pipe that supplies magnetic ink 14 from the main tank to the ink tank 16, and the magnetic ink 14 is supplied from the main tank to the ink tank 16.
It has a supply pump 20 to send the water. Reference numeral 19 denotes a collection pipe, which automatically collects the magnetic ink 14 supplied from the main tank in excess of a certain amount in the ink tank 16 in the direction of arrow C to keep the liquid level of the magnetic ink 14 in the ink tank 16 constant. ing. 2
Reference numeral 1 denotes a flow path resistance variable means for changing the flow path resistance of a part of the supply path 15. In this embodiment, the flow path resistance variable means 21 is composed of a permanent magnet, and is rotatably attached to a rotating shaft 22, and is moved from the position shown in FIG. 5 to the position shown in FIG. 6, or from the position shown in FIG. It is constructed so that it can be rotated to the position shown in the figure by a suitable mechanism (not shown). When the flow path resistance variable means 21 is in the state shown in FIG.
5 to increase the flow path resistance by applying an attractive force to the magnetic ink 14 passing through the magnetic ink 14, and in the states shown in FIGS. 4 and 6, no attractive force is applied to the magnetic ink 14 and the flow path resistance is increased. do not have.

Next, the magnetic ink 14 in the above-described configuration
Explain the flow.

Main tank (not shown) and ink tank 16
Between the supply pipe 18 and the supply pump 20
The magnetic ink 14 is supplied to the ink tank 16 by this. Further, the remaining amount of ink is collected from the collection pipe 19 to keep the liquid level in the ink tank 16 constant at all times.

First, the supply pump 17 supplies the magnetic ink 14 in the direction of arrow A to fill the supply path 15 and the opening A. When the magnetic ink passes through the opening A, a holding force is exerted on the magnetic ink by the bumping magnet 12 and the auxiliary magnet 13, but since the supplying force of the supply pump 17 is strong, the ink passes through this area. When passing through opening A, magnetic ink 1
4 is the stylus 1 even without the power of the supply pump 17
0 and the attraction force of the bumping magnet 12, the stylus 10 is attached to the tip. The period during which this supply pump 17 is operating is the period up to T ₁ shown in FIG.
A pressure head of +h is acting on the opening A. When the supply pump 17 is stopped at this point, the pressure head of H4 at the opening A is changed from the pressure head of _H4 when the supply pump 17 is activated.
Because of the negative pressure head acting on the magnetic ink 14 momentarily filled with the supply pump 17, the magnetic ink 14 attempts to return to the ink tank 16. But supply pump 1
When the flow path resistance variable means 21 is brought into the state shown in FIG. Therefore, as a result, the flow resistance in the supply channel 15 increases, the flow of the magnetic ink 14 slows down, the damping amplitude decreases, and the tolerable pressure head at the opening A decreases as shown in FIG. The flow path to the tip of the stylus 10 is reliably constructed without exceeding the limit value _H3 .
The negative pressure that momentarily acts on the opening A is supplied by the supply pump 1.
7, it is sufficient to keep the flow path resistance variable means 21 in the state shown in FIG. 5 from T ₁ to T ₄ (approximately 1/2 of the predetermined negative pressure H). Figure 7
If the channel resistance variable means 21 is returned to its original state at the position _T4 as shown in FIG. 6, the supply performance of the supply channel 15 during recording will not be hindered. After forming an appropriate protuberance at the tip of the stylus 10 in this manner as shown in FIG.
Recording is performed by flying the magnetic ink 14 having a raised tip onto the recording surface 24. The magnetic ink 14 consumed during recording passes through the supply path 15 and the opening A to the tip of the stylus 10 automatically (supply pump 17
without activating. ) supplied.

As described above, the supply path from the ink tank 16 to the tip of the stylus 10 can be reliably formed with a simple configuration.

FIG. 8 shows another embodiment of the present invention.
Reference numeral 5 denotes a channel resistance variable means provided around a part of the supply channel 15, which is composed of an electromagnet. In this embodiment, as in the previous embodiment, the supply pump 17 is stopped and at the same time the switch 26 is closed for a certain period of time to apply an attractive force to the magnetic ink 14 using an electromagnet to increase the flow path resistance. The same effects as those of the previously described embodiment can be obtained.

In the embodiment shown in FIG. 9, the flow path variable means 25 is constituted by an electromagnet, similar to the embodiment shown in FIG. 8, and the same effects as in the previous embodiment can be obtained.

In the embodiments shown in FIGS. 10 and 11, a valve 27 is provided in the supply path 15 to constitute a flow path variable means. That is, the valve 27 is attached to the rotating shaft 28, the rotating shaft 28 is rotated, and the 11th
Supply pipe 15 by putting it in the state shown in the figure.
This is intended to increase the flow path resistance for a certain period of time immediately after the supply pump 17 is stopped as described above, and it is possible to obtain the same effect as the above-mentioned embodiment.

As described above, according to the present invention, the flow path variable means is provided in a part of the supply path, and the flow path resistance of the supply path is increased by the flow path variable means for a certain period of time immediately after the supply pump is stopped. , the supply path can be reliably constructed without momentarily applying a large negative pressure to the opening.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram showing a conventional magnetic ink recording device, Fig. 2 is a diagram showing a raised state of the tip of a stylus, and Fig. 3 is a diagram showing a pressure head acting on an opening in a conventional magnetic ink recording device. 4 to 6 show a schematic configuration of a magnetic ink recording apparatus according to an embodiment of the present invention, and FIG. 4 shows a state before the opening and the supply pipe are filled with magnetic ink. Figure 5 shows a state in which the supply pump is stopped after forming a flow path and the flow path resistance is increased by the flow path resistance variable means, and Figure 6 shows a state in which the flow path resistance is increased with the flow path formed. It is a figure showing the state where it does not do. FIG. 7 is a diagram showing the pressure head acting on the opening A, FIGS. 8 to 11 show other embodiments of the present invention, and FIGS. 8 and 9 show the flow path resistance variable means using an electromagnet. FIGS. 10 and 11 are cross-sectional views showing an example in which the flow path resistance variable means is formed by a valve. 10...Stylus, 12...Elevation magnet, 1
3... Auxiliary magnet, 14... Magnetic ink, 15...
Supply path, 16... Ink tank, 17... Supply pump, 21, 25, 26, 27... Channel resistance variable means.

Claims (1)

[Claims] 1. A multi-stylus recording needle made of a magnetic material;
an uplift magnet attached to the multi-stylus recording needle; an ink supply path having an opening at one end close to the uplift magnet; and an ink supply path connected to the other end of the ink supply path and located below the opening. an ink tank located at and containing magnetic ink; a supply pump disposed in the ink supply path for sucking up the magnetic ink from the ink tank to the opening; and an ink tank located between the ink tank and the opening. a flow path resistance variable means provided in a part of the supply path, the supply pump is stopped and the pressure head of negative pressure is applied to the opening due to the head difference from the opening to the ink liquid level in the ink tank. , the magnetic ink recording apparatus is characterized in that the flow path resistance variable means is operated for a certain period of time after the supply pump is stopped to increase the flow path resistance of the ink supply path through which the magnetic ink flows. . 2. The magnetic ink recording device according to claim 1, wherein the flow path resistance variable means is composed of a permanent magnet. 3. The magnetic ink recording device according to claim 1, wherein the flow path resistance variable means is constituted by an electromagnet. 4. The magnetic ink recording apparatus according to claim 1, wherein the flow path resistance variable means is constituted by a valve, and the valve increases the flow path resistance without blocking the ink supply path.