JPH06297727A - Ink jet printer - Google Patents

Abstract

PURPOSE:To reduce the number of heaters to conserve electric power and to eliminate the leakage of ink by supplying granular ink to an ink storage tank equipped with a granular ink melting means if necessary from a granular ink storage tank. CONSTITUTION:A carriage 1 is loaded with an ink jet head, a first ink storage tank 5 and an ink supply device 7. A second ink storage tank 50 is arranged at the position opposed to the carriage. When the liquid level of each color ink 11 stored in the first ink tank 5 in a liquid state is lowered from the position of a thermistor 22, the carriage 1 is moved to the required position of the second storage tank 50. The lever 24 of the ink supply device is pulled by a solenoid 26 and the supply lever 52 of the second ink storage tank 50 is pushed to revolve a cup 62 around a fulcrum 60 to supply granular ink 9 to the first ink storage tank 5. Thereafter, the granular ink 9 is melted by a head heater 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet printer, and more particularly to a method for supplying ink to a printing section.

[0002]

2. Description of the Related Art Conventionally, in a hot-melt ink jet recording apparatus in which a solid ink block having a predetermined size at room temperature is heated and melted, and the ink droplets are recorded on a recording medium by using an ink jet ejecting means, US Pat. No. 4,814,786 is known as a method of supplying ink to the ink.

US Pat. No. 4,814,786 is shown in FIG.
First, the heater 81 provided in the head ink pot portion 80, the heater 85 provided in the head outside ink pot portion 84, and the cable heater 96 provided in the supply pipe 82 are energized. The heaters are heated to melt the solidified ink in each part. Next, the head outside ink pot portion 84 is passed through the supply pipe 82 through the head ink pot portion 80.
The melted ink 86 melted and stored in the cartridge is driven by driving the pump portion 88.

A lid 90 is provided on the ink fountain portion 84 outside the head to prevent dust and the like from entering the inside.

The head carriage 92 prints on the recording medium while reciprocating in the direction perpendicular to the conveying direction of the recording medium.

Since the supply pipe 82 is connected to the head ink fountain portion 80 mounted on the head carriage 92, it moves to the left and right as the head carriage 92 moves during printing.

[0007]

However, in order to melt the solidified ink, it is necessary to provide a heater in each part, which complicates the configuration and requires a large power source. There is also a problem that it takes time to melt the solidified ink.

Further, since the lid 90 provided on the ink pot portion outside the head 84 is easily opened, there is a problem that the melted ink in the ink pot portion outside the head 84 can be easily touched by opening the lid 90. there were.

Further, the supply pipe 82 is made of a heat-resistant resin, and the head ink bottle portion 80 and the head outside ink bottle portion 84 are made of aluminum 93 having a high thermal conductivity.
94 and resin 97, 98 for insulating aluminum from the outside air. Therefore, due to the difference in the linear expansion coefficient of the material, improper fixing of the connecting portion is likely to occur, and ink leakage may occur.

The present invention has been made in order to solve the above-mentioned problems, and reduces the number of heaters to save electric power, ink leakage does not occur, and the melted ink cannot be easily touched. It is an object of the present invention to provide an inkjet printer provided with.

[0011]

In order to achieve this object, an ink jet printer of the present invention comprises a first ink provided with an ink melting means for heating and melting fruit ink and supplying the ink to an ink jet head. A storage device, a second ink storage device for storing a large amount of fruit granule ink, and a means for supplying the fruit ink from the second ink storage device to the first ink storage device as required.

[0012]

According to the ink jet printer of the present invention having the above-mentioned structure, the ink supplying means supplies the fruit ink from the second ink reservoir for storing a large amount of the fruit ink to the first ink reservoir as needed. The fruit melting ink is heated and melted by the ink melting means provided in the first ink reservoir, and the ink is supplied to the ink ejecting head.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a hot melt ink jet printer capable of color printing will be described below with reference to the drawings.

First, before describing the mechanical portion of the present embodiment, the block configuration of the control unit of the present embodiment will be described with reference to FIG.

The control of the ink jet printer of this embodiment is performed by the control unit 17 including a CPU, ROM, RAM and the like. Control unit 1
7, a thermistor 22, a micro switch 70, and a display lamp 72 are connected, and further, a head heater 15 and a piezoelectric element 16 are connected via a head control circuit 18, and a solenoid 26 via a drive circuit 20. , Carriage motor 34, and platen drive motor 38 are connected.

Next, the mechanical portion of this embodiment will be described with reference to FIGS.

The carriage 1 includes an ink jet head 3
The first ink reservoir 5 and the ink supply device 7 are mounted.

The ink jet head 3 mounted on the carriage 1 has a plurality of main color inks 1 melted inside.
Ink 1 having a required color of 1 is ejected onto the paper 13 on the platen 12 to perform recording on the paper 13. As shown in FIG. 6A, the inkjet head 3 includes a nozzle 14 filled with the ink 11, a head heater 15 that heats the ink 11, and a piezoelectric element 16 disposed on the wall surface of the nozzle 14. The ink 11 on the surface of the inkjet head 3 does not go out of the inkjet head 3 due to surface tension.

When the head control circuit 18 applies a voltage to the piezoelectric element 16 in response to a print command from the control unit 17, the piezoelectric element 16 deforms and presses the ink 11 in the nozzle 14. As shown in FIG. 6B, the compressed ink 11 jumps out of the inkjet head 3 and adheres to the paper 13 to form dots on the paper 13.
Further, the deformation amount of the piezoelectric element 16 changes depending on the applied voltage amount. Therefore, when the amount of voltage is lowered, the amount of deformation of the piezoelectric element 16 is small, and the amount of ink ejected outside the inkjet head 3 is small. Further, the ink amount can be increased by increasing the voltage amount.

Further, as a means for judging whether the ejected dot is the main color or the mixed color, the control unit 17 has print image data, and the ink of the main color required for each dot at the time of printing. Is selected, and a print command is sent to the inkjet head 3.

The first ink reservoir 5 mounted on the carriage 1 has four colors of cyan, magenta, yellow and black.
The color inks are divided into four tanks 8 so that they can be stored, and the respective tanks 8 are arranged side by side. The top of each tank 8 is open to receive the grain ink 9. A part of the head heater 15 extends to the bottom of each tank 8 and is connected to the inkjet head 3 by an ink conduit 21. The ink in the first ink reservoir 5 is always heated and melted by the head heater 15 to be in a liquid state. The ink 11 in the liquid state is supplied to the inkjet head 3 by the ink conduit 21.

The amount of ink in the first ink reservoir 5 is detected by the thermistor 22, and when the liquid level of the ink 11 in the liquid state falls below the thermistor 22, the control unit 17 causes the ink supply device to be described later. 7, a fixed amount of the fruit grain ink 9 is supplied. Ink 11
Is supplied by the grain ink 9, so that it is quickly melted. In addition, the liquid level detection by the thermistor 22 is
A current is passed through the thermistor 22 to determine the voltage drop. The fact that the voltage drop is different between air and liquid is utilized, and it is well known in the art. Therefore, detailed description is omitted.

The ink supply device 7 mounted on the carriage 1 is composed of a lever 24 and a solenoid 26. When the lever 24 is pulled by the solenoid 26, the lever 24 rotates about a fulcrum on the carriage 1 as a center of rotation and pushes a supply lever 52 of a second ink reservoir 50, which will be described later, to load the first lever mounted on the carriage 1. The grain ink 9 is supplied to the ink reservoir 5.

The carriage 1 is supported by two guide shafts 32, and is arranged so that it can be reciprocated in the direction perpendicular to the transport direction of the transported paper 13 via a timing belt 36 by driving a carriage motor 34. There is.

The platen 1 is placed at a position facing the carriage 1.
2 are arranged. A paper guide 42 and nip rollers 44 and 46 are provided below the platen 12,
The nip rollers 44 and 46 are arranged so as to come into pressure contact with the platen 12 by a spring (not shown). A nip roller 48 is also provided on the downstream side of the platen 12 in the sheet conveying direction, and the nip roller 48 is arranged so as to be pressed against the platen 12 by a spring (not shown). Paper 13 conveyed from the upstream side of platen 12
Is nipped by the platen 12 and nip rollers 44, 46, 48 which are rotated by a driving means (not shown) driven by a platen drive motor 38, and the paper feeding during recording is controlled by the control unit 17.

A second ink reservoir 50 is arranged at a position facing the carriage 1. Second ink reservoir 50
Is an ink case 54 having a substantially short shape as a whole, and four ink tanks 56 are provided in the ink case 54.
Are juxtaposed. In each ink tank 56, there are four solid colors, cyan, magenta, yellow, and black, which are solid at room temperature.
Colored grain inks 9 can be stored respectively. At the top of each ink tank 56, a lid 58 that can be opened and closed for containing the fruit grain ink 9 is provided. Each of the ink tanks 56 has a quadrangular cross-sectional shape, becomes thinner toward the bottom, and has a hole at the bottom. A cup 62 that rotates about 60 as a fulcrum is provided on the bottom with a hole. The cross-sectional shape of the cup 62 is a quadrangle, and the cup 62 includes a supply lever 52.
Is attached. In addition, the cup 62 is a flat spring 6
4 and the bottom stopper portion 6 of the ink tank 56.
It hits 6 and has stopped. In the cup 62, the fruit grain ink 9 that has fallen from the ink tank 56 is contained.

Inside the ink tank 56, there is provided a micro switch 70 having an actuator 68 for detecting the presence or absence of the fruit grain ink 9. The presence or absence of the grain ink 9 is determined by the weight of the grain ink 9. As shown in FIG. 1, when the amount of the fruit grain ink 9 is large, the weight of the fruit grain ink 9 pushes the actuator 68 to turn on the micro switch 70. Based on the signal detected by the micro switch 70, the control unit 17 determines the presence or absence of the fruit ink 9. As shown in FIG. 4, when the amount of the fruit ink 9 is low, the micro switch 70 is turned off. Based on the signal detected by the micro switch 70, the control unit 17 determines that there is no fruit ink 9, and turns on the indicator lamp 72 provided outside the ink case 54 to prompt the user to replenish the fruit ink 9.

Further, the chassis 76, to which the second ink reservoir 50 is attached, hides the upper portion of the tank 8 which is a supply port for the grain ink 9 of the first ink reservoir 5 mounted on the carriage 1. It is located in. The chassis 76 is arranged so as to hide the upper portion of the tank 8 of the first ink reservoir 5 because dust, dust,
This is also to prevent the molten ink from being touched by hand.

Next, the first mounted on the carriage 1
Ink 1 of each color in a liquid state in the ink reservoir 5
The operation when the liquid level of No. 1 is below the thermistor 22 will be described with reference to FIGS.

As shown in FIG. 2, when the liquid level of each color ink 11 in the first ink reservoir 5 becomes lower than the thermistor 22, the control unit 17 supplies the carriage 1 with each color in the second ink reservoir 50. Move to position. Next, as shown in FIG. 3, the lever 24 is pulled by the solenoid 26 by the ink supply device 7 mounted on the carriage 1, and the lever 24 rotates about a fulcrum on the carriage 1 as a rotation center. The supply lever 52 of the ink reservoir 50 is pushed. When the supply lever 52 is pressed, the cup 62 integrated with the supply lever 52 rotates about 60 as a fulcrum and supplies the fruit ink 9 to the first ink reservoir 5 mounted on the carriage 1. Since the ink 11 is supplied as the granule ink 9, the ink is quickly melted by the head heater 15, the liquid level of the ink rises above the thermistor 22, and the ink supply is completed.

According to this embodiment having such a structure, the number of heaters is reduced to save power, there is no ink leakage, and an ink jet printer provided with an ink supply device that cannot easily touch molten ink is provided. can do.

In place of the lever 24 and solenoid 26 of the ink supply device 7 mounted on the carriage 1,
The supply lever 52 of the second ink reservoir 50 may be directly moved by a solenoid, a motor or the like.

By changing the sizes of the tank 8 of the first ink reservoir 5 and the cup 62 of the second ink reservoir 50 for each color, the amount of ink that can be supplied at one time can be varied.

An embodiment in which the present invention is applied to a hot-melt type ink jet printer capable of color printing has been described above with reference to the drawings. The tank 8 of the first ink reservoir 5 and the second ink reservoir Ink tank 5 of container 50
6, by increasing or decreasing the number of cups 62 etc., a single color, and
It can be a hot-melt ink jet printer capable of printing in multiple colors.

[0035]

As is apparent from the above description,
INDUSTRIAL APPLICABILITY The inkjet printer of the present invention can provide an inkjet printer provided with an ink supply device in which the number of heaters is reduced to save power, ink does not leak, and molten ink cannot be easily touched.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing first and second ink reservoirs and ink supply means before ink supply according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the first ink reservoir of the above embodiment at the time of ink empty.

FIG. 3 is a cross-sectional view showing the first and second ink reservoirs and the ink supply means at the time of ink supply in the above embodiment.

FIG. 4 is a cross-sectional view showing a second ink reservoir of the above embodiment at the time of ink empty.

FIG. 5 is a perspective view showing an outline of an inkjet printer provided with the ink supply device of the above embodiment.

FIG. 6 is a conceptual diagram of an inkjet head of the inkjet printer of the above embodiment.

FIG. 7 is a block diagram illustrating a configuration of a control unit of an inkjet printer including the ink supply device according to the above embodiment.

FIG. 8 is a cross-sectional view showing an ink supply unit of a conventional inkjet printer.

[Explanation of symbols]

 3 Inkjet Head 5 First Ink Reservoir 7 Ink Supply Device 8 Tank 9 Fruit Ink 11 Ink 15 Head Heater 24 Lever 26 Solenoid 50 Second Ink Reservoir 52 Supply Lever 56 Ink Tank 60 Support Point 62 Cup 64 Hiki Spring 66 Bottom Stopper Section

Claims (1)

[Claims] 1. A hot-melt ink-jet printer that melts when heated and records using solid-grain ink that is solid at room temperature. The ink melts when the grain-ink is heated and melted to supply the ink to the ink jet head. A first ink reservoir provided with a means, a second ink reservoir for storing a large amount of fruit ink, and, if necessary, a second ink reservoir for supplying fruit ink to the first ink reservoir And an inkjet printer.