JPS608951B2 - Ink ejection head clogging prevention device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for preventing clogging of nozzles of an ink jet head used in an ink jet L type recording system, and more particularly, to a device for preventing clogging due to drying of ink during non-recording. It is something.

The ink jet recording method, which is known as a recording method for facsimile machines, scans an ink chamber equipped with a nozzle at a constant speed in one direction, converting input pulse signals into pressure pulses. , the pressure inside the ink chamber is instantaneously increased, thereby causing a constant amount of 4.
jetting a certain amount of ink and depositing it on the recording sheet,
This is a recording method in which a recording sheet is intermittently sent by small distances in a direction perpendicular to the direction of movement of the ink chamber, and an image is recorded on the recording sheet by a collection of ink dots that adhere in accordance with an input signal.

The first problem with such a recording method is that the nozzles tend to become clogged with ink and other substances. In other words, the nozzle must have the ability to eject a very large amount of ink with great force in the correct direction.
Inevitably, the diameter must be very thin and a certain length is required, making it easy to cause clogging.Furthermore, when the ink used is deposited as ink dots on the recording sheet, it will cause damage to the recording sheet. Since it must have sufficient contrast, it must be highly concentrated, and it must dry quickly on the recording sheet, so it must have good drying properties, and these conditions must be met. This overlap tends to cause nozzle clogging.A particular problem is nozzle clogging due to dry and fixed ink during non-recording times.

Conventionally, an effective method for preventing clogging due to ink drying and sticking during non-recording is to use a suitable cap to cover the nozzle opening and seal the nozzle opening from the outside. Are known. However, with the conventional method, there is a drawback that the cap does not cover the nozzle opening properly due to a slight deviation in the mutual positional relationship, reducing the sealing effect by half. When covering, there was a drawback that it hit strongly against the surface where the nozzle opening was formed.

When the cap hits the above-mentioned surface while covering the nozzle opening, and the ink chamber receives a shock, the ink inside the ink chamber flows out of the nozzle opening due to the reaction, resulting in so-called ink dripping that stains the cap and the above-mentioned surface. If this sticks, the elastic ring attached to the top cap will not be able to adhere satisfactorily to the surface, reducing the sealing effect.The object of the present invention is to avoid the above-mentioned disadvantages, and to An object of the present invention is to provide an ink ejecting head clogging prevention device capable of preventing nozzle clogging due to dry and fixed ink during non-recording.

Hereinafter, the present invention will be described by way of examples with reference to the drawings.

FIG. 1 shows only the essential parts of an example of a clogging prevention device embodying the present invention.

That is, in FIG. 1, numeral 1 is an ink jet head, numeral 2 is a carriage, numeral 3 is a shaft for the carriage, and numeral 4 is a carriage shaft.
is a cap, 5 is a compressible spring, 6 is a support body,
7 is an actuator, 8 is a spiral spring, 9 is a plunger solenoid, and 10 is an air
Each damper is shown.

That is, the ink jetting head is mounted on a carriage 2 disposed on a shaft 3, and is conveyed by the carriage 2 in the direction of the shaft 3.

The ink ejection head has a home position set at a specific position away from the recording area, and when not recording, a message saying "Stays at this home position.
The position of the ink ejection head shown in the figure is the home G position. It goes without saying that an ink ejection nozzle opening is formed on the side of the ink ejection head facing the cap 4 in FIG. 1.

(See Figure 2). Note that the reference numeral 11 indicates an ink supply tube. As shown in FIG. 2, the cap 4 includes a lid portion 41, a support shaft 42, and a ring 43.

The lid part 41 has a disk shape, and a low-height hollow cylinder-shaped protrusion 411 is provided on the green part of the circumference in the opposite direction to the support shaft 42, and a protrusion 411 is provided in the central part. A ring 43 made of an elastic material is iron-mounted on the disc-shaped portion 412.The ring 43 is attached to the nozzle opening 1 of the ink ejection head.
The position of the nozzle opening is opposite to the surface on which 5 is formed, and corresponds to the inside of the ring 43. The support shaft 42 of the cap 4 is
After passing through the compressible spiral spring 5, the spring 5
The hole 61 drilled in the support body 6 resists the elastic force of
1 is fixed.

Due to the elastic force of the spring 5 and the action of the stopper 421, the cap 4 is supported on the support 6' so that its support shaft 42 is substantially perpendicular to the surface of the support 6. However, the inner diameter of the hole 610 is , is slightly larger than the diameter of the cylindrical support shaft 42. Therefore, the cap 4 is given the following degree of freedom of movement relative to the support 6. That is, the first
The second degree of freedom is the freedom of movement in the length direction of the support shaft 42, and the second degree of freedom is the freedom of movement perpendicular to the support shaft 42, with the western part of the engaging part shell hole 610 as the fulcrum. , and the degree of freedom of swing in two mutually independent directions.

Therefore, due to the second degree of freedom, the cap 41 is provided with a conical movable region with the engaging portion as the apex.
The lower part of the support 6 is bent horizontally as shown in FIG. 1, and projecting pieces 61 are provided at both ends of this horizontal part in correspondence with each other and are bent upward. 6
2 shares the support member 12 fixed to the immovable part of the device and the shaft 13 passing through them, so that the support member 6
is swingably supported by a support member 12 by a shaft 13.

The end of the horizontal portion of the support 6 opposite to the side that supports the cap 4 is formed to be larger than the width of the support 6, and this portion is bent upward so that the actuator It serves as an engagement piece 63 for the 7. The engagement piece 63 is provided with a hole 63a that extends downward to the right when viewed from the engagement piece 63 toward the cap 4. The actuator 7 is inserted into the hole 63a. A pin 72 fixed to a rising piece 71 at the operating side end is movable in the length direction of the elongated hole 63a. The actuator 7 is mounted on a turret 14 that stands on the Fudobe village, and is swingable around the turret 14 in a horizontal plane.

On the driving part side of the actuator 7, there is an actuation village 91 of the plunger solenoid 9 and an actuation village 1 of the air damper 10.
It is pivoted to 01.

Further, a compressible spring 8 is stretched between the driving portion side of the actuator 7 and a pin 81 that is set up against a stationary member of the device. Plunger solenoid 9, when energized, is actuated and pulls actuator 7 with its operating punch 91, causing it to rotate clockwise in FIG. 1 about shaft 14.

At this time, the elastic force of the spring 8 acts as a resistance force, but the action of the plunger solenoid 9 is of course far superior to this resistance force. On the other hand, the air damper 10 exerts a resistance force only when the actuator 7 rotates counterclockwise around the shaft 14 in FIG. 1 so as to reduce the angular velocity of this rotation. Now, the operation of this device is as follows.

That is, when recording is started, first, the plunger solenoid 9 is energized.

This causes the actuator 7 to rotate clockwise around the shaft 14. As the pin 72 moves due to this rotation, the rising piece 63 in which the elongated hole 63a that engages with the pin 72 is formed is pushed upward, and the support body 6 rotates around the shaft 13, as shown in FIG. Rotating clockwise, the cap 4 opens the nozzle opening 15 (second
(see Fig. 3) is separated from the surface on which it is formed. Next, the ink jet head 1 is conveyed along the shaft 3 by the carriage 2 to a recording area, and recording is performed. During this time, plunger. The solenoid 9 is de-energized and the cap 4 returns to the starting position. When the recording operation is completed, the plunger solenoid 9 is energized again, moves by repeating the process described above, and waits for the ink ejection head to return to its home position.In this state,
When the ink jet head 1 returns to its home position, this is detected by a known appropriate means and the energization of the plunger solenoid 9 is stopped.

FIG. 1 shows exactly this situation. Until plunger solenoid 9 is de-energized,
The clockwise moment applied to the actuator 7 around the shaft 14 is released, and instead, the counterclockwise moment due to the elastic force of the spring 8 becomes dominant, and the actuator 7 moves as shown in FIG. However, since the resistance force of the air damper 10 acts at this time, the rotation is relatively slow. As the actuator 7 rotates counterclockwise, the support 6 rotates clockwise around the shaft 13, and the cap 4 supported by the support 6 slowly moves toward the nozzle opening 15 of the ink jet head. moves toward the surface on which is formed, and comes into flexible contact with the upper surface. At this time, the actuator 7 still has room to rotate in all directions counterclockwise, and the actuator 7 rotates further. The elastic force of the spring 8 is set to be superior to the elastic force of the spring 5 attached to the support shaft 42 of the cap 4, and as the actuator 7 rotates,
The spring 5 is compressed, and the elastic force of the spring 5 is applied to the cap 4.
This acts as a pressing force that presses against the surface on which the nozzle row 5 is formed, and as a result, the ring 43 comes into pressure contact with the surface, the contact portion deforms according to the surface, and the disc-shaped portion 41
2, the space near the nozzle row 5 is sealed from the outside. (See FIG. 3) When the nozzle port 15 of the ink jet head is sealed using this device, as described above, the buffering action of the air dassopar 10 prevents the cap 4 from touching the ink jet head. Since it is performed flexibly, the above-mentioned ink dripping does not occur, and the cap 4 has a conical movable area with the engaging portion as the apex relative to the support body 6, and can also move in the direction of the support shaft. In addition, since the elastic force of the spring 5 presses against the surface where the nozzle opening is formed, the nozzle row 5 can always be reliably sealed by simply pressing the cap 4 against the surface.

As described above, according to the present invention, it is possible to provide an ink jet head clogging prevention device that can effectively prevent nozzle clogging due to dry and fixed ink during non-recording.

It should be noted that the air damper 101 may be replaced with a known buffering means as appropriate, and it goes without saying that the forms of the support and actuator, and the form of their engagement should not be limited to the above examples.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing only the essential parts of an example of a clogging prevention device embodying the present invention. FIG. 2 is a front sectional view showing how the cap is supported in the example of the device shown in FIG. FIG. 3 is a front sectional view showing the nozzle opening sealed by the cap in the example of the apparatus shown in FIG. 1... Ink jet head, 4...
・Cap, 5... Compressible spring, 6...
...Support, 7...Actuator, 8...
・・・Tension spring, 9・・・Plunger・
Solenoid, 10...Air Dan/Diichi, 15...Nozzlero. Rare l figure hakama figure 2 figure 3

Claims (1)

[Claims] 1 A ring 43 made of an elastic material is arranged so that the nozzle opening of the ink jetting head 1 in the home position corresponds to the inside of the ring 43, and the nozzle opening of the ink jetting head is formed when not recording. A cap 4 that seals the nozzle opening by pressing the ring 43 against the surface of the nozzle, and a cap 4 that is loosely fitted onto the support shaft 42 of the cap 4 so as not to come off, and the cap 4 is tilted with respect to the loosely fitted part. a swingable support body 6 that supports the cap 4 so as to
A compressible spring 5 fitted to the support shaft 42 between the lid portion 41 of the cap 4 and the support body 6; an actuator 7 that engages with the support body 6;
A plunger solenoid 9 applies a force to the support body 6 via the actuator 7 to move it away from the ink jetting head 1, and an elastic force to press the cap 4 against the ink jetting head 1. The elastic force means 8 acts on the support body 6 via the actuator 7, and the elastic force by the elastic force means 8 causes the cap 4 to
An apparatus for preventing clogging of an ink ejecting head, comprising a buffer means 10 for applying a resistance force to the actuator 7 to soften the contact when the actuator contacts the ink ejecting head 1.