JPH0691895A - Ink jet device using hot melt ink - Google Patents

Abstract

PURPOSE: To minimize the handling of ink by a person. CONSTITUTION: An ink jet apparatus is equipped with a head 10 equipped with a reservoir 18, a container 22 housing solid ink and a heater 24 heating and melting the ink provided in the container 22 and, when the head 10 is connected to the container 22, the heater 24 is operated to melt ink to supply liquid ink to the reservoir 18. When the head is not connected, the heater 24 is not operated and the deterioration of the ink is suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet device,
In particular, the ink used in the ink ejecting apparatus is of a phase change type and relates to the ink ejecting apparatus when it can be called hot melt ink.

[0002]

2. Description of the Related Art Phase change type inks, that is, hot melt inks used in an ink jet apparatus are characteristically solid at room temperature. When heated, the ink melts to a jettable consistency. And
This hot melt ink can be ejected from various devices.

When a liquid ink is used, the ink is, of course, supplied in a liquid state. Ink is commonly stored in some type of closed container prior to delivery to the ink ejector. When employing hot melt inks, different solutions are needed to provide a reliable ink supply and to minimize human intervention. At the same time, heating the hot melt ink for too long results in deterioration of the ink, so it is not desirable to constantly heat the entire supplied hot melt ink.

In an on-time fusing (fusing on demand) mechanism that supplies ink to a reservoir carried by an ink ejector in a drawing head, long term heating can be avoided and occurs as a result of such heating. It is clear that deterioration of the ink can also be avoided. The amount of ink that can be used in such a mechanism is limited by the amount of ink that can be mounted on the drawing head.

It is an object of the present invention to provide a hot melt ink supply mechanism that minimizes human handling of the ink. Another object of the present invention is to provide a hot melt ink supply mechanism capable of reliably supplying ink to an ink ejecting apparatus. Yet another object of the present invention is to minimize excess heating and consequent ink degradation.

Another object of the present invention is to provide a hot melt ink supply mechanism capable of supplying a large amount of ink without human intervention.

[0007]

In view of these and other objects of the invention, solid state ink is stored in place and a movable drawing head includes at least one ink ejector and a reservoir connected thereto. To have. The drawing head is moved to an ink pouring position adjacent to a home position where ink is stored, where the solid ink also melts into a liquid state and fills the reservoir of the draw head. The movement of the head to the ink pouring position, the melting and filling of the reservoir with ink can be repeated as often as required, as long as the ink is needed.

In a preferred embodiment of the invention, the solid ink comprises a mass of ink and is provided with heating means thermally coupled to its ends. The ink mass is advanced to maintain thermal coupling with the heating means, which operates on demand when ink is needed.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG.
It is disclosed to have a head 10 mounted for movement along a scanning path indicated by 2,14. The head 10 includes an ink ejection type drawing mechanism that provides an array of ink ejectors having orifices 16. The head 10 includes a box-shaped reservoir 18 having a tank 20 located on the back of the head 10.

Reservoir 18 has a limited capacity, in other words, reservoir 18 can store a quantity of ink heated by a heater (not shown), which is reasonable for reasonable print speeds. Reliably actuate the ink ejector over time. However, the ink capacity is limited.
The head 10 is configured so that it can be moved to the refill position shown in phantom to refill the reservoir 18 of the head 10 and thus the reservoir 20. In the re-injection position, the head 10 is located below a solid-state ink feeder that can be phase-changed to a molten state by heating. As shown, the feeder comprises a tubular vessel 22 with a heater 24 electrically powered by conductive wires 26,28. As shown in FIG. 1, the reservoir 20 is properly positioned when it is in close proximity to the ink supply within the tubular container 22, so that the molten ink will pass through the flow passage 30 and into the reservoir 2.
It is possible to flow into 0. Thus
The reservoir 18 in the head 10 is filled with ink.

Referring now to FIG. 2, the tubular container 22 is illustrated as surrounding a coil spring 32 which abuts a fastener 34 which is secured to the container 22 by screws 36. The other end of the spring 32 is in contact with the movable insert 38 which is in contact with one end of the solid ink mass 40. The other end of the ink block 40 is in contact with a groove 42 juxtaposed with the heater 24 embedded in a container 44 fixed by a screw 46. The groove 42 allows ink to flow into the opening 50. Vessel 44 contains a thermistor 48 and other temperature sensing elements.

When the temperature of the heater 24 rises, the end of the ink mass 40 which is in contact with the plate 42 melts. The melted ink then passes through the groove 42 and the opening 50 in the tubular container 22.
Flow into. It is the flow from the openings 50 that forms the flow 30 of molten ink shown in FIG. As also shown in FIG. 2, the container 22 includes openings 52, 54 associated with a light source 56 and a photodetector 58. If there is a sufficient amount of ink 40, the light from light source 56 is blocked, and the light is not detected by detector 58, the resulting signal from the detector is that there is an adequate amount of ink 40. Instruct that. However, when the amount of the ink 40 becomes so large that the detector 58 cannot be shut off, the detector 5
8 indicates that the ink supply amount is small. This will be discussed in more detail below in connection with FIG.

Referring now to FIG. 3, the heater controller 6
0 activates or deactivates the heater 24. To control the temperature of the heater 24, the heater controller 60 responds to the signal from the thermistor 48. Preferably, the heater 24 is capable of operating for a period of time when refilling of ink into the reservoir 18 is required. The timer 62 that sends an input signal to the heater control unit 60 for this fixed length of time
Controlled by. Of course, it is important to set a timer and start heating when ink is needed in the reservoir 18. This point is determined by the liquid level sensing circuit 64 which receives the appropriate liquid level indicating signal from the reservoir. However, the timer 62
It can only be set if the detector 58 indicates the presence of the proper amount of ink 40 as illustrated in FIG.

In the present invention, it is important that the melting begins only when the head 10 is in place below the tubular container 22. A position detector 66 is provided for this purpose, which allows control of the heater when the head 10 is in the proper position. While the preferred embodiment of the invention has been illustrated and described, it will be appreciated that other embodiments and variations are within the true spirit and scope of the invention as claimed. For example, it is possible to remove the heating plate 42 and use a solid ink supply containing a heater element that extends the length of the ink. If such an ink supply is utilized, the ink advancing spring 32 can be eliminated. On the other hand, if a heating plate is used, it may be desirable to use a means other than spring 32 to advance the ink. It may also be desirable that the light detection mechanism, including the light source 56 and the light detector 58, and the heater container 44 be separable from the container 22. Still further, due to spatial concerns, container 22 may be pivotable 90 °.

[0015]

As is apparent from the above description, according to the present invention, an ink ejecting apparatus using hot melt ink is provided with a reliable ink supply mechanism which minimizes human handling. Thus, an ink ejecting device is provided which allows the extra heating of the ink orifice and the resulting deterioration of the ink to be minimized.

[Brief description of drawings]

FIG. 1 is a perspective view of an ink ejecting apparatus showing a preferred embodiment of the present invention.

FIG. 2 is a cross-sectional view of the ink supply device of FIG.

FIG. 3 is a block diagram of a controller for the device shown in FIG.

[Explanation of symbols]

 10 ... Head 16 ... Orifice 18 ... Reservoir 20 ... Tank 22 ... Tubular container 24 ... Heater 30 ... Flow path 32 ... Coil spring 40 ... Ink lump 42 ... Groove 44 ... Container 48 ... Thermistor 50 ... Opening 56 ... Light source 58 ... Light detector 60 ... Heater controller 62 ... Timer 64 ... Liquid level detection circuit 66 ... Position detector

Claims (4)

[Claims] 1. A scanning type ink jet head having a reservoir and at least one ink jetting device, a fixed solid ink supply device, and the scanning type ink jet head coupled to the solid ink supply device. A hot melt ink having means for heating and melting the solid ink to flow the melted ink to the reservoir, and means for inhibiting heating and melting when the head is not connected to the solid ink supply device. Ink jet device used. 2. The ink jet apparatus according to claim 1, wherein the solid ink is a lump. 3. The ink jet apparatus according to claim 1, wherein the heating means comprises a plate thermally coupled to an end of the ink mass. 4. The ink ejecting apparatus according to claim 2, wherein the ink mass comprises an advancing means for advancing the ink mass, and the ink mass maintaining thermal coupling with the heating means.