JPH06143558A - Hot-melt type ink jet printer - Google Patents

Abstract

PURPOSE:To rapidly restart a printing operation by a hot-melt type ink jet printer without taking a time until supplied ink is melted in an ink jet head by forming a structure for supplying ink to the head in a simple structure. CONSTITUTION:Spherical solid ink 12a having a diameter of about 1.6cm supplied into a solid ink reservoir 16 is moved to a position in contact with a heater 28 of an ink feeder 22 provided under the reservoir 16, and heated by the heater 28. Then, the feeder 22 is rotated around a shaft 26, and the heated ink 12a is supplied to an ink jet head.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot melt ink jet printer.

[0002]

2. Description of the Related Art Conventionally, a hot-melt type ink jet printer heats and melts solid ink at room temperature,
It is known that the melted ink is jetted onto a sheet by a well-known ink jet type ink jet head to perform recording.

In such a hot melt type ink jet printer, the ink jet head is heated in order to melt the ink and eject it onto the paper.

The structure of the ink jet head 50 is shown in FIG.

The ink jet head 50 has an ink storage chamber 51 for storing the ink 12b in a liquid state, a jetting device 56 for jetting the ink 12b stored in the ink storage chamber 51 from a jet outlet 56a, and ink in the ink storage chamber 51. 12
It is composed of a thermistor 36a for detecting the remaining amount of b.

On the wall portion forming the ink storage chamber 51, the ink 1 in the solid state is introduced from the outside into the ink storage chamber 51.
An opening for supplying 2a is formed, and an opening / closing body 52 for opening / closing the opening is rotatably attached to the wall portion. The opening / closing body 52 is always biased by a spring (not shown) so as to close the opening,
Normally, the ink storage chamber 51 is kept in a state of being shielded from the outside.

The ejection device 56 ejects the ink 12b from the ejection port 56a based on data processed by a central processing unit (hereinafter referred to as CPU) 30 which will be described later.

The thermistor 36a is connected to the CPU 30 via a liquid ink detection circuit. And
When the thermistor 36a is present in the ink 12a,
Due to the difference in the amount of heat radiation (resistance value) when exposed to the air, the remaining amount of the ink 12b in the ink storage chamber 51 is 1.5.
It is detected whether it is cc or less.

The heating element 54 for heating the ink stored in the ink storage chamber 51 is the ink jet head 5
It is attached at a position adjacent to the bottom surface on the outer wall side of 0. The heating element 54 controls the current supplied by the CPU 30 to move the ink jet head 50 to about 1%.
Heat to 25 ° C.

These ink jet head 50 and heating element 5
4 is mounted on a carriage (not shown), and reciprocates along a print line on a platen (not shown) as the carriage is moved.

An ink supply device 60 for supplying the ink 12a into the ink storage chamber 51 of the ink jet head 50 is fixed to a frame of a hot melt type ink jet printer as shown in FIG. A solid ink reservoir 62 for storing ink in a solid state, and an ink transfer body 66 provided below the solid ink reservoir 62 for transporting the ink 12a in the solid ink reservoir 62 into the ink storage chamber 51. It consists of

The ink reservoir 62 has a substantially funnel shape, and the lower end portion of the substantially funnel shape has a tubular shape through which only one substantially spherical ink having a diameter of about 1.6 cm can pass. is doing. Further, the ink reservoir 62 is rotatably provided with a lid 64 for opening and closing the upper opening of the funnel.

The ink transfer body 66 has an arc shape rotatably provided around a shaft 70. The ink transfer body 66 is formed with a passage 66a for guiding the supplied ink 12a into the ink storage chamber 51. The inlet of the passage 66a is connected to the ink reservoir 62.
Communicates with the tubular part of the. On the other hand, the exit of the passage 66a is
It is open at the right end of the passage 66a. In addition, the passage 66
Below the inlet of a, the ink 12a is
A switch 68 for detecting whether or not it is supplied from is attached. The switch 68 is turned on when the ink 12a is supplied from the ink reservoir 62, and is turned off when the ink 12a is not supplied.

The ink 12a supplied from the ink storage unit 62 to the ink transfer body 66 is moved to a position where the opening / closing body 52 of the ink jet head 50 faces the ink transfer body 66 (replenishment), and then, as shown in FIG. 11 (a), FIG.
As shown in FIGS. 11B and 11C, the ink transfer body 66
As the ink is rotated to the right of the shaft 70, the right end of the ink transfer body 66 rotates and opens the opening / closing body 52, and the ink 12a passes through the passage 66a by its own weight and is stored in the ink storage chamber 51. Move to.

Also, Japanese Patent Application No. 4-
As described in the specification and drawings attached to the application of No. 45935, there is also one that supplies the ink to the ink jet head after the ink is melted.

[0016]

However, in the conventional ink jet printer, it takes time for the solid ink supplied at room temperature to melt in the ink jet head, and the printing operation must be interrupted for a while. There is a problem that does not happen.

Further, when the melted ink is supplied to the ink jet head, a pump, a tube, a heater and the like are required, which causes a problem that the number of parts is increased. Further, since the tube is always connected to the moving ink jet head, there is a problem that rattling occurs in the connecting component and the melted ink leaks.

The present invention has been made to solve the above-mentioned problems, and supplies ink in a solid state to an ink jet head to relatively reduce the number of parts, and
It is an object of the present invention to provide a hot-melt ink jet printer that prevents ink from leaking and does not require time to melt the supplied ink.

[0019]

In order to achieve this object, a hot-melt ink jet printer of the present invention comprises a first ink storage means for melting and storing ink ejected from an ink jet head, and a small piece of ink. Second ink storage means for storing the ink forming the ink, heating means for heating the ink stored by the second ink storage means at a temperature equal to or lower than the melting temperature of the ink, and the heated ink for the first ink storage. And an ink supply means for supplying the means.

[0020]

In the hot melt type ink jet printer of the present invention having the above structure, the second ink storage means stores the ink in the form of small pieces, and the heating means stores the ink stored in the second ink storage means. The ink is heated at a temperature below the melting temperature of the ink. Then, the ink supply unit supplies the ink heated by the heating unit to the first ink storage unit that melts and stores the ink ejected from the ink ejecting head.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing the structure of the ink supply device 20. FIG. 2 is a perspective view showing the appearance of the hot melt inkjet printer 10.

Hot melt ink jet printer 1
Near the center of the upper part of 0, a paper discharge port 14 for discharging the recorded paper is provided. That is, after the characters and symbols are recorded on the paper supplied from the paper supply port by the well-known inkjet type ink jet head 50 (shown in FIG. 3), the paper is discharged to the paper discharge port 14. To be done.

In the upper part of the hot melt type ink jet printer 10 which is located on the front left side of the paper discharge port 14, the melting point temperature is about 80 ° C., and there are four colors of cyan (blue), magenta (red), yellow and black. Four solid ink reservoirs 16 for separately storing the types of ink 12a are arranged in rows.

Each solid ink reservoir 16 is shown in FIG.
As shown in, it has a substantially funnel shape. The solid ink 12 that has been replenished is provided at the lower end of the substantially funnel shape.
A tubular passage through which only one a can pass is formed, and is open obliquely downward to the right. In addition, an opening portion 25 is formed in the tubular passage portion, into which a stopper portion 24 formed in an ink transfer body 22, which will be described later, enters. Further, the ink reservoir 16 is rotatably provided with a lid 18 for opening and closing the upper opening of the funnel. The solid ink reservoir 16 is replenished with and stored with a substantially spherical solid ink 12a having a diameter of about 1.6 cm.

Below the solid ink reservoirs 16, there are provided ink transfer members 22 each formed of a resin having poor heat conductivity in a substantially arc shape.

The ink transfer body 22 is rotatable about a shaft 26 by a driving force of an ink supply motor (not shown). The ink transfer body 22 has a passage 2 for guiding the ink 12a supplied from the solid ink reservoir 16 into the ink storage chamber 51 of the ink jet head 50.
2a is formed. The inlet of the passage 22a communicates with the tubular passage of the ink reservoir 16. On the other hand, the outlet of the passage 22a is open at the right end of the passage 22a.

Further, the passage 22a extends leftward from the communicating portion by a length corresponding to one ink 12a,
A switch 38a is provided on the extended portion.
This switch 38a is used to store the ink 12a in the ink reservoir 1
It is detected whether or not it is supplied from 6. This switch 68
Is turned on when the ink 12a is supplied from the ink reservoir 16, and is turned off when the ink 12a is not supplied.

Further, a heater 28 is arranged on the inner wall portion of the extended portion of the passage 22a. This heater 28
Is heated by the heater drive circuit 44 described later to heat the contacted ink 12a to about 65.degree. At this time, the ink transfer body 22 supporting the heater 28
Since it is made of a resin having poor heat conductivity, the heat from the heater 28 is efficiently transferred to the outside and is not lost, and efficiently heats only the contacting ink 12a. Further, since the heat generated by the heater 28 is not transferred to the ink 12a in the solid ink storage device 16, neither the ink 12a in the solid ink storage device 16 is deformed nor the adjacent inks 12a are fused.

Furthermore, the passage 22a of the ink transfer body 22
The stopper portion 24 is formed so as to project in a substantially L-shape above the communicating portion. The tip of the stopper 24 is
It is located at a distance (1.6 cm) equal to the diameter of the ink from the upper surface of the outer peripheral frame forming the passage. In the stopper portion 24, the ink transfer body 22 has a shaft 26.
In a state in which it is rotated counterclockwise around and is stopped (the state shown in FIG. 1), it enters the opening 25 and closes the tubular passage of the ink reservoir 16 by about 30%. Stop passing 12a.

The solid ink storage device 16 corresponds to the second ink storage means of the present invention. In addition, the ink transfer body 22
Corresponds to the ink supply unit of the present invention. Further, the heater 28 and the heater drive circuit 44 correspond to the heating means of the present invention.

On the other hand, inside the hot-melt type ink jet printer 10, four ink jet heads 50 and heating elements 54 for respective colors mounted on a carriage (not shown) are provided.
Are provided so as to be capable of reciprocating along a print line on the platen.

Since the ink jet head 50, the heating element 54, and their arrangement are the same as those in the conventional technique, the description of the conventional technique will be referred to for the description thereof, and the description thereof will be given here. Omit it. The ink storage chamber 51 of the ink jet head 50 corresponds to the first ink storage means of the present invention.

Next, the electrical construction of the hot melt type ink jet printer 10 arranged in this way will be described.

FIG. 4 is a block diagram showing the electrical construction of the hot melt ink jet printer 10.

In this hot melt type ink jet printer 10, a read only memory (hereinafter referred to as ROM) 32, a random access memory (hereinafter referred to as RAM) 34, a liquid ink detection circuit 36, a solid ink detection circuit 38, a carriage motor. The drive circuit 40, the ink supply motor drive circuit 42, the heater drive circuit 44, and the other 48 are electrically connected to a central processing unit (hereinafter referred to as CPU) 30 via a bus 49.

The ROM 32 stores a program for causing the CPU 30 to control the above components.

The data processed by the CPU 30 is temporarily stored in the RAM 34.

The liquid ink detection circuit 36 includes the thermistor 36a and outputs data for detecting the remaining amount of the ink 12b in the ink storage chamber 51 to the CPU 30.
To enter.

The solid ink detection circuit 38 includes the switch 38a, and inputs data to the CPU 30 to detect whether or not the ink 12a is supplied from the solid ink reservoir 16 into the ink transfer body 22. To do.

The carriage motor drive circuit 40 is a circuit for driving a motor for moving the carriage, and is drive-controlled by the CPU 30.

The ink supply motor drive circuit 42 is a circuit for driving an ink supply motor (not shown) and reciprocally rotating the ink transfer body 22 around the shaft 26 by its driving force, and the operation control by the CPU 30. To be done.

The heater driving circuit 44 includes the heater 2
The ink 12 which is supplied with the current to contact the heater 28
It is a circuit for heating a and is driven and controlled by the CPU 30.

Further, the other 48 is an ejection device 56, a well-known sheet feeding device, or the like.

Next, the operation of such a hot melt ink jet printer 10 will be described.

First, the hot-melt ink jet printer 10 is loaded with a known paper feed cassette containing paper by the user, and the lid 18 is opened.
The ink 12a is replenished in the solid ink reservoir 16.
The state of the ink supply device 20 at this time is shown in FIG. To explain this state, the tubular passage of the ink reservoir 16 is blocked by the stopper portion 24 of the ink transfer body 22, and the supplied ink 12a is not supplied to the ink transfer body 22 side. .

After that, the power switch is turned on to start the operation.

When the operation is started, the hot melt ink jet printer 10 performs an operation of supplying ink to the ink storage chamber 51 of the ink jet head 50 in order to perform a printing operation.

FIG. 5 is a flow chart showing the operation of supplying the ink 12a to the ink jet head 50.

In this operation, the CPU 30 firstly, based on the program, the solid ink detecting circuit 38.
The data is read from the ink and the ink transfer body 2 is read from the data.
It is determined whether or not the ink 12a is present in 2 (S10).

As described above, since the ink 12a is not supplied into the ink transfer body 22, the determination step S1
The determination of 0 is “No”, and then step S11 is executed.

In step S11, the ink supply motor drive circuit 42 is driven to move the ink transfer body 22 from the state shown in FIG. 6 to the state shown in FIG.
6 is rotated clockwise, the stopper 24 is removed from the solid ink reservoir 16, and the ink 12a is moved to the ink transfer body 22 side. Then, after that, the ink transfer body 22 is returned to the original state by rotating the ink transfer body 22 from the state shown in FIG. 7 to the state shown in FIG. The ink 12a that has moved to (1) is further moved to the extension of the passage 22a of the ink transfer body 22 and is heated by the heater 28 (S11).

Then, since the ink 12a is supplied into the ink transfer body 22 in step S11, the determination in the determination step S10 becomes "Yes", and then the heater drive circuit 44 is driven to drive the heater 28 in step S12. To heat the ink 12a supplied into the passage 22a of the ink transfer body 22 to about 55 ° C. Since this temperature is about 10 ° C. lower than the melting point temperature of the ink 12a, the ink 12a is not melted in the ink transfer body 22 by the heating by the heater 28.

After that, the CPU 30 reads the data from the liquid ink detection circuit 36 and determines from the data whether or not the liquid ink 12b is in an appropriate amount in the ink storage chamber 51 (S13).

First, the ink 12 is stored in the ink storage chamber 51.
Since there is no b, the liquid ink 12b is not detected, and the determination in this determination step S13 is “No”. Next, in step S14, the carriage motor drive circuit 40 is operated to drive the carriage motor, thereby causing the carriage to move. The opening / closing body 52 of the mounted ink jet head 50 is moved to a position (ink supply position) facing the ink supply device 20.

Then, in the next step S15, the ink supply motor drive circuit 42 is driven to rotate the ink transfer body 22 clockwise about the shaft 26, from the state shown in FIG. 9A. 9 (b) and 9 (c)
Move to the state shown in. Along with that, the right end of the ink transfer body 22 pushes open the opening / closing body 52, and next,
The heated solid ink 12a is supplied to the ink storage chamber 51 by its own weight. At this time, the solid ink reservoir 1
Solid ink 12 stopped by stopper 24 of No. 6
a is from the tubular passage of the solid ink reservoir 16 to the stopper 2
When 4 is detached, it moves to the ink transfer body 22 side. Then, after that, by returning the ink transfer body 22 to the original state shown in FIG. 9A, the next ink 12a that has moved to the ink transfer body 22 side moves into the ink transfer body 22.

Then, the carriage motor drive circuit 40 is operated to move the ink jet head 50 to the same position as the position before being moved by this ink supply processing (S16).

Then, the ink supply process is completed.

On the other hand, by executing steps S10 to S16 of the ink supply process,
When the ink 12b is supplied into the ink storage chamber 51 and the liquid ink 12b is detected by the thermistor 36a, the determination in the determination step S13 becomes "Yes", and thereafter, the ink supply is performed without executing anything. The process ends.

The ink supply process is executed at predetermined time intervals.

As described above, by the ink supply process, the ink supply device 20 is driven to supply the ink 12a into the ink storage chamber 51 until the liquid ink 12b is detected by the thermistor 36a in the ink storage chamber 51. It

The solid ink 12a supplied into the ink storage chamber 51 by the above ink supply process is the heater 2
Since it is heated to a temperature close to the melting point temperature by 8, it is quickly melted by being heated by the heating element 54 after being supplied into the ink storage chamber 51.

After the ink 12b is supplied to the ink storage chamber 51 of the ink jet head 50 as described above, the CPU 3
Based on the program, 0 controls the conveyance of the sheet corresponding to the data input from an external computer or the like and the drive control of the ejection device 56 to form an image on the sheet.

According to such a hot-melt type ink jet printer, the structure for supplying the ink to the ink ejecting head has a simple structure, and it takes time until the supplied ink is melted in the ink ejecting head. There is an effect that the printing operation can be restarted quickly without causing any trouble.

[0065]

As is apparent from the above description, according to the hot-melt ink jet printer of the present invention, the structure for supplying the ink to the ink jet head has a simple structure and the supplied ink is used. It does not take time to be melted in the ink jet head, and the printing operation can be restarted quickly.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a configuration of an ink supply device.

FIG. 2 is a perspective view showing the appearance of a hot melt inkjet printer.

FIG. 3 is a cross-sectional view showing a configuration of an ink jet head.

FIG. 4 is a block diagram showing an electrical configuration of a hot melt inkjet printer.

FIG. 5 is a flowchart showing an operation of supplying ink to the ink jet head.

FIG. 6 is a cross-sectional view showing a state of the ink supply device when solid ink is replenished in the solid ink reservoir.

FIG. 7 is a cross-sectional view showing a state of the ink supply device when the ink transfer body is rotated to remove the stopper from the solid ink reservoir.

8 is a cross-sectional view showing a state of the ink supply device when the solid ink is moved into the ink transfer body 22 by rotating the ink transfer body 22. FIG.

FIG. 9A is a cross-sectional view showing a state of an ink supply device and an ink jet head immediately before supplying solid ink. FIG. 9B is a sectional view showing the states of the ink supply device and the ink jet head during the solid ink supply operation. FIG. 9C is a sectional view showing a state of the ink supply device and the ink jet head when the solid ink is supplied.

FIG. 10 is a cross-sectional view showing a configuration of a conventional ink supply device.

FIG. 11A is a cross-sectional view showing a state of a conventional ink supply device and an ink jet head immediately before solid ink is supplied. FIG. 11B is a cross-sectional view showing the states of the conventional ink supply device and the ink jet head during the solid ink supply operation. FIG. 11C is a cross-sectional view showing the states of the conventional ink supply device and the ink jet head when solid ink is supplied.

[Explanation of symbols]

 10 Hot Melt Inkjet Printer 12a Solid Ink 12b Liquid Ink 16 Solid Ink Reservoir 22 Ink Transfer Body 28 Heater 30 CPU 32 ROM 44 Heater Drive Circuit 49 Bus 50 Ink Jet Head 51 Ink Storage Chamber

Claims (1)

[Claims] 1. A hot-melt ink-jet printer that prints using ink that is solid at room temperature and that melts when heated to a high temperature. The first ink that melts and stores the ink ejected from an ink ejection head. Storage means, second ink storage means for storing small pieces of ink, heating means for heating the ink stored by the second ink storage means at a temperature below the melting temperature of the ink, and the heated An ink supply means for supplying ink to the first ink storage means.