JPS61225057A - Charge deflection type ink jet printing apparatus - Google Patents

Abstract

PURPOSE:To attain the miniaturization of the titled apparatus and cost reduction, by arranging the parts of an ink supply system except the control circuit of an ink jet process on a carriage. CONSTITUTION:A carriage base 11 is constituted of an aluminum or iron plate and a main guide 9 and a rear guide 10 are fixed to a carriage base 11 by screws. The part below the carriage 11 constitutes a carriage scanning system. A carriage mount type ink supply system is integrally constituted on the carriage base 11 to be attached to said carriage base 11 by rivets in a detachable manner. The ink supply system is constituted so as to be roughly separated into four laminated base plates 12, 13, 14, 15 which are, in turn, mutually fixed by rivets or ultrasonic welding and ink pipelines, a liquid chamber or the like are provided in the laminated base plates and various units, such as valves, solenoids and heads, etc. are mounted on the laminated body.

Description

[Detailed Description of the Invention] 149! The present invention relates to a charge deflection type inkjet printing device.

Figure 4 is a configuration diagram for explaining an example of a conventional charge deflection type inkjet printing device.

200 is an inkjet ejection head, 201 is an excitation circuit for exciting the inkjet ejection head 200,
202 is a charged electrode, 203 is a deflection electrode, 204 is a gutter, and 205 is a charged phase detection electrode.

206 is a heater that heats the ink supplied to the inkjet ejection head 200, 207 is a filter, 210 is a platen, 211 is a recording paper, 212 is a deflection amount detection electrode, 2
13 is a deflection height detection circuit, 214 is a charge phase detection circuit,
215 is a charge control circuit, 216 is an ink recovery pump, 2
17 is an ink cartridge; 218 is an ink pressure pump and accumulator; 219 is a pulse that controls on/off the ink supplied to the inkjet head 200;
Reference numeral 20 denotes an ink supply path, with the I side mounted on the carriage and the ■ side attached to the main body side, with the A-A line as the boundary. In the conventional charge deflection type inkjet printing device as described above, the ink supply system requires independent space within the printer cover, and is fixed to the printer cover or frame housing with screws or the like. As shown.

There are two types: those placed on the carriage ■ side (movable side) and those fixed with screws on the frame housing (main body) side (fixed side). Therefore, the connection between the movable side and the fixed side is performed by a carriage harness, and this carriage harness consists of more than ten ink supply tubes, ink recovery tubes, high voltage lines, signal lines, etc., making it possible to reduce size and cost. It was hindering me.

1-Drinking The present invention was made in view of the above-mentioned circumstances.
In particular, all parts of the ink supply system except the control circuit of the inkjet process can be placed on the carriage, thereby eliminating the connection between the fixed part and the movable part of the ink supply system by the carriage harness, and supplying ink. At the same time, it eliminates the harmful effects caused by the connection between the fixed and moving parts of the system.

This was done with the aim of reducing the size and cost of the device.

In order to achieve the above object, the present invention comprises laminating a plurality of plate-like members to form a laminate, and forming an ink supply path in the laminate to provide an ink pressurizing pump, a filter, The present invention is characterized in that an ink supply system connecting an accumulator, a valve, etc. is formed, and an ink pressurizing pump, a valve, an ink jet ejection head, and a charge deflection unit are attached to the laminated body. Hereinafter, the present invention will be explained based on examples.

FIG. 1 is a block diagram for explaining an embodiment of an inkjet printing apparatus according to the present invention.

1 is a platen, 2 and 2' are pressure rollers, 3 is a deflector, 4 is a paper pail roller, and 5 is a recording paper.

The recording paper 5 is inserted from behind the platen 1 by hand or by an automatic sheet feeder, passes between the deflector and the platen, and is ejected in the direction of the arrow. Reference numeral 6 denotes side plates, and there is one side plate 6 on each side, and a main guide shaft 7 is installed between both side plates.
is penetrated and fixed, and the stay 8 is similarly penetrated. 9
10 is a main guide, 10 is a rear guide, 11 is a plate-shaped carriage base, and main guide 9. and rear guide 10
is made of resin, the carriage base 11 is made of aluminum or iron plate, and the main guide 9 and rear guide 10 are fixed to the carriage base 11 with screws. 12
is a timing belt (with teeth), and one of the six pulleys at both ends fixed endlessly to both side plates 6.6 is an idler, which applies tension to the belt 12 and removes the walnut. The other pulley is a motor pulley. The other end 9' of the main guide 9 has the same shape as the tooth profile of the belt, and the tooth portions of the main guide 9 are in close contact with the carriage base 11, thereby preventing the belt from slipping. When a carriage motor (not shown) (for scanning) rotates, the belt 12 rotates, and the main guide 9 and rear guide 10 move along the main guide shaft 7 and stay 8, and are integrally fixed to the main guide 9 and rear guide 10. The carriage base 11 moves back and forth. In addition,
In the figure, the part below the carriage base 11 constitutes a carriage scanning system. In addition, although not shown, there are sensors and sensor plates that determine the start position and home position. Furthermore.

There is a carriage-mounted ink supply system (hereinafter simply referred to as the ink supply system) mounted on the carriage base 11, but these are integrally constructed and are attached to the carriage base 11 with screws and can be removed. There is. The ink supply system is roughly divided into four plate-shaped substrates 12, 13, 1.
4.15 are laminated, and the mutual substrates are fixed by screws or ultrasonic welding, and ink pipes,
A liquid chamber and the like are provided, and each unit such as a valve, a solenoid, a head, etc. is mounted on this stacked body.

The explanation will be given below in the order of the ink flow paths.

Reference numeral 16 denotes the ink cartridge body, which has a substantially rectangular shape. There is a space 17 inside this ink cartridge 16, and a bellows-shaped (polyethylene thin plate) in-crank 18. There are diluent tanks 19, and each tank independently contains new ink and diluent. The diluent tank 19 contains pure water (which is used to replenish the ink in use to lower the viscosity when the viscosity rises above a predetermined value).
Contains preservatives). The upper part of each bellows has a stepped portion, and a spring 20, 21 is inserted between the stepped portion and the stepped portion of the ink cartridge 16.

This spring normally compresses the bellows, forcing the liquid in the tank downward. The other end of the bellows has a narrow opening 22,23.

Rubber bushes 24 and 25 are attached to the tip of the bellows so as to enclose the narrow openings 22 and 23. The narrow opening 22.23 and the bushing 24.25 are in close contact with each other to prevent ink from leaking. There are flange 26, 27 in the middle part of the bushing, and when the ink cartridge main body 16 is completely fitted into the flange, the bellows comes out (moves) when installing the cartridge.
is prevented. Reference numerals 28 and 29 are hollow needles made of stainless steel, and the tips are sharpened so that the bushings can be easily inserted into them. When the cartridge body 16 is pulled out, the bushing 24
．． 25, and as soon as it comes out of the hollow needles 28 and 29, the openings of the bushings 24 and 25 close due to their rubber elasticity, so ink will not drip, and when inserting the ink cartridge 16, the bushings should be made hollow. By inserting the needle into the hollow needle, the ink inside the bellows will be absorbed by the lower end 30 of the hollow needle.
It flows up to ゜31. The lower end 30.31 is the rubber sheet 3
2, and there is no further flow of ink. An ink liquid chamber (tank) 41 is dug into the substrate 13.
A slight space is provided at the top of the tank 41.

This is to improve the mixing of the diluted liquid and to enlarge the opening for venting air to the gutter, as will be described later. 42°43 are the upper limit line and lower limit line of ink.

The ink detection electrode rod 45 is provided at a height equal to the lower limit line 42, and 646 is a lead wire for detection.

Next, ink replenishment will be explained. When the ink in the tank 41 is between the lines 42 and 43, the ground electrode 4
7 and the detection electrode 45 are electrically connected by ink, so the resistance value shows a certain value, but as the ink is consumed,
When the ink falls below the line No. 3, the electrical connection between these electrodes is lost and the resistance value becomes high. This determines that the ink is running out, and replenishes ink. That is, in the present invention, the detector 45
When the ink level is below the detection line 43, the resistance value between the detection electrode 45 and the ground electrode 47 is much larger than when the ink level is above the detection line 42. .

The lack of ink is detected by detecting this change in resistance value, and the new ink supply valve is opened for a certain period of time under the control of a CPU (not shown) to supply a certain amount of new ink in the bellows 18 to the ink liquid chamber 41. insert.

FIG. 2 is a diagram for explaining a method of replenishing ink. To replenish ink, first, the solenoid 48 is energized. Then, the actuator 49 rotates around the fulcrum 51 to release the pressure on the valve seat 32 and normally release the spring 5.
the valve seat 32 is pressed against the hollow needle 28), the ink in the bellows flows down with the help of internal pressure, and
Go through it and fall into the tank from 53. When the solenoid 48 is energized for a time corresponding to the ink height changing from the position of line 43 to the position of line 42, and then the energization is turned off, the valve seat 32 is brought into close contact with the hollow needle 28 by the spring 5o, and the ink flows down. is blocked, and the ink supply stops. If the resistance value between the detection electrode 45 and the ground electrode 47 does not decrease after a certain period of time has passed, that is, if the ink chamber 41 is not filled with ink, it is determined that the ink in the bellows 18 has run out. , even if there is still a large amount of diluent remaining in the diluent bellows 19,
The new ink and diluent integrated cartridge 16 is replaced with a new one.

When replenishing diluted liquid, the increase in viscosity is detected by a method such as pressure increase detection, and the bellows 19 is activated based on the detection signal.
Then, the valve communicating with the ink liquid chamber 41 is opened, and the diluent in the other bellows, that is, the bellows 19, flows into the ink liquid chamber 41. Since the diluted liquid is usually not conductive, it is difficult to install a sensor to detect the remaining amount.
As mentioned above, if the diluent is provided in the cartridge that is integrated with the new ink, only 10 sensors will be needed, and the diluent can be replaced at least as often as the ink is replaced, which will prevent mold from forming. etc., and reliability can be improved. Separate solenoids 48 are provided for ink and diluent.

By opening the diluent solenoid, the pipe 53 is opened in the same manner as above.
The diluted liquid is dropped into the tank 41. The diluted liquid that falls into the tank will spread on the liquid surface, but in order to quickly mix it, it is best to move the carriage from side to side.

Next, the path of ink within the tank will be explained. The ink coming out of the liquid chamber 41 passes through the first filter 54 and rises once through the conduit 56 and enters the second filter 58 through the conduit 57. 55.59 is a rubber grommet. The reason why the first filter 54 enters the second filter 58 from the top to the bottom is to serve as an air trap.

In other words, a considerable amount of air is contained in the liquid chamber 41, and as the liquid level fluctuates, this air passes through the first filter 54 and enters the conduit 56. When the channel is raised once and the air is discharged upward from the conduit 57, and only the ink is passed through the second filter 58, the air is drawn out from the conduit 60. In addition, the pipe line 60
and the liquid chamber 41 are connected by a conduit 61. The ink that has passed through the second filter 58 rises again from the conduit 62, descends from the suction port 63 of the pump, passes through the inserter 68, passes through the valve seat 64 and the valve 65, and enters the liquid chamber 66. 69 is a valve seat on the discharge side, 70 is a valve, and 71 is an inserter. 67
72 is a diaphragm, 72 is an armature, 73 is a fixing screw for the armature and diaphragm, 74 is a pump solenoid core, and 75 is a coil. Now, when the coil 75 is energized (approximately 50 Hz), the armature 72 is attracted to the iron core side, the diaphragm 67 is bent downward, and the liquid chamber 6
6 becomes negative pressure, ink flows from the suction side 63 into the liquid chamber 6.
When the current is turned off, the ink in the liquid chamber 66 is pushed up by the restoring force of the diaphragm 67 and comes out from the ejection side.This process is repeated at 50Hz, increasing the pressure of the ink and causing it to be ejected. (type pump), the ink discharged from the discharge side passes through the third filter 76 and enters the accumulator (ACC). The accumulator is a liquid chamber for controlling the pulsation of the pump, and 77 is a diaphragm.
78 is a liquid chamber. In other words, pressurized ink enters the liquid chamber 78 from below, but because it enters intermittently, the pressure value changes. This is absorbed by the deflection of the diaphragm 77 to keep the pressure constant.

The third filter 76 is called a main filter, and has the finest mesh of, for example, 3 .mu.m and 710 .mu.m in two layers. The ink leaving the accumulator attempts to enter the valve liquid chamber 80 through the conduit 79. In FIG. 1, the valve body 81 is closed because the valve liquid chamber 80 is in the OFF state, and the ink is sealed by the rubber valve 82. In FIG. 3, when an ink jetting command is issued, the valve solenoid 87 is energized and the armature 88 is pulled.
The lever 84 moves around the O-ring 85 in the direction of the arrow, which opens the pipe 79 side and at the same time opens the pipe 92 side (valve E
XT) is closed, ink fills the liquid chamber 80, and then
It jumps out of the head through the 93 traffic pipe. 95 is an O-ring that also serves as an ink seal and a fulcrum for vertical adjustment of the head. The head and valve are jointless, and when assembling the head, loosen the screw 96 and attach the flange 9.
After loosening 4 and expanding O-ring 95, insert and remove the head. After that, the screw is tightened to force the O-ring into close contact with the pipe 93, thereby eliminating the joint and allowing easy replacement.

When stopping ink ejection, the solenoid 87 is de-energized. Then, the return spring 86 moves the lever 84 in the direction opposite to the arrow, resulting in the state shown in FIG. At this time, the pipe line 92 (EXT) side opens, so 1. Valve liquid chamber 8
The ink in 0 passes through conduit 83 and is discharged from conduit 91. At this time, it may open suddenly, and since the pipe diameter is large, the ink inside the head may also be emptied, creating a negative pressure inside the head and drawing air from the nozzle. 89 provides resistance in the flow path. This is done by controlling the gap between 90 and 97. The ink coming out of the pipe line 91 enters the tank 41. Further, some of the ink leaving the accumulator passes through the pipe line 79 to the valve liquid chamber 80, and some passes through the pipe line 99 and is released to the outside. The purpose of the conduit 99 is to remove air, etc., measure pressure, and replace ink. By loosening the screw 98, ink, air, etc. are discharged.

100 is a head housing, and the ink that enters through a pipe 93 passes through a final filter (built in the head), and then passes through a pipe 1 in a ceramic helad body 101.
04 and exits from the nozzle 1°5. 102 is a piezo vibrator, 103 is a heater, and the heater 103 is patterned on the outer periphery of the body, directly heating the body and heating the ink inside. 106 is a charging electrode, 107 is a cap, and the cap 107 pushes the charging electrode 106. The jetting direction of the head is adjusted using a spring 109 and a screw 10B. When the screw 10B is turned, the head moves up and down around the O-ring 95, thereby maintaining a constant positional relationship (height) with the gutter 110.

111 is a deflection electrode (high voltage side), 112 is a deflection electrode (GN
D) The ink that entered the gutter was conventionally collected by a collection pump, but in the illustrated example.

It falls naturally and enters the ink tank 41. This eliminates the need for a recovery pump and reduces costs. 11
2 is a pipe line for recovered ink.

- As is clear from the above description, according to the present invention, in the inkjet printing process, all parts of the ink supply system except the control circuit are arranged on the carriage, so the overall size of the printer is extremely large. It is smaller, and the disadvantages caused by separation of the movable part and the fixed part are eliminated. In addition, in the carriage, functions can be consolidated and the number of parts can be significantly reduced.

Significant cost reduction is possible. Furthermore, conventionally.

The ink tubes that were connected by the carriage harness are no longer needed because they form the circulation system on the carriage.
A carriage harness can be configured with signal lines and high voltage wires,
Since a flexible tube can be used for the signal line, there are advantages such as a very low cost.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram for explaining one embodiment of the present invention, FIGS. 2 and 3 are diagrams each showing a part of an ink supply system, and FIG. 4 is a diagram of a conventional inkjet printing system. 1 is a diagram showing an example of a photocopying device. 1...Platen, 5...Recording paper 12-15...
Plate member, 16... Cartridge, 18... New ink bellows, 19... Diluent bellows, 41... Ink liquid chamber, 45... Ink liquid detection electrode, 54, 58,
76... Filter, 74... Pressure pump solenoid, 78... Accumulator liquid chamber, 80... Valve liquid chamber, 100... Inkjet head. Figure 2 Figure 3

Claims (1)

[Claims] Constructing a laminate by laminating a plurality of plate-like members,
An ink supply path is formed in the laminate to form an ink supply system that connects an ink pressure pump, a filter, an accumulator, a valve, etc., and an ink pressure pump, a valve, an ink jet ejection head, a charge deflection unit, etc. A charge deflection type inkjet printing device equipped with a charge deflection type inkjet printing device.