JPH1034963A - Eyelid assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an eyelid assembly for preventing solidification of liquid. SOLUTION: This eyelid assembly in a continuous ink jet print head comprises an eyelid for enabling injection of a print liquid droplet from a print head, an eyelid seal 1b for capturing and introducing a fluid through the throat part of a catcher in relation to the eyelid, and a heater 6 integrated with an eyelid seal to block solidification of the fluid on the eyelid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to continuous ink jet printing technology, and more particularly, to a heater element formed on an eyelid of a continuous ink jet print head.

[0002]

2. Description of the Related Art An ink jet printer in which a printhead includes one or more rows of orifices that receives a conductive recording fluid from a pressurized fluid supply manifold and ejects the fluid as multiple rows of parallel streams. Printing devices are known. Printing devices using such printheads selectively charge and deflect the droplets in each stream, depositing at least some droplets on the print medium and capturing the remaining droplets. An image is formed by collecting it in the apparatus.

Preventing the ink from drying in the capture surface area when the ink jet print head is not operating;
Alternatively, a means must be provided to seal the printhead to prevent ink from dripping from the jet and fouling the device and adjacent work surfaces. Therefore,
It is desirable to attach the eyelid device to the print head. During the start-up operation of a continuous ink jet printing device, the eyelid captures fluid and directs the flow of fluid through the trap. In the starting operation, a jet is formed, the high-voltage electrode is dried, and a charge voltage is generated (ON).

While the printing device is in operation, but not performing a printing operation, the eyelid diverts the flow of ink from the resonator and returns it to the print head. After the charging voltage has been supplied, the eyelid can be opened at any time. Typically, the eyelids remain closed during standby, during loading of printing paper, during printing interruptions by the operator, and during other normal interruptions. When the lid is closed, it protects the printing paper and equipment below the printhead, even if the jet is bent or a printhead error occurs that is not automatically detected.

[0005] Existing printheads are configured to reduce the rate of evaporation to minimize changes in ink density in the printing device.

[0006]

In such a configuration,
The airflow through the trap is reduced to a minimum. As the air flow in the trap decreases, air cannot be completely removed from the area around the inkjet when the lid is closed, and is not removed by water vapor due to local evaporation of the ink from the ink droplets. T) The air is saturated. Thus, the temperature of the air approaches the temperature of the ink (5-10 ° C.) above the temperature of the lid seal.
As a result, the ink in the saturated air solidifies on the eyelid. As coagulation proceeds, the volume of the liquid increases and drips from the eyelid, adversely affecting the high voltage electrode.

Attempts have been made to solve the problem of coagulation on the eyelid by increasing the airflow or reducing the ink temperature, but all have failed due to the limited airflow in the trap. Is over.

[0008] There is a need to provide a means for preventing liquid from coagulating on the eyelids of a continuous ink jet print head.

[0009]

SUMMARY OF THE INVENTION This need is met by the heater element of the eyelid according to the present invention, wherein the surface temperature of the eyelid seal assembly is controlled by local ambient air to prevent solidification. Maintained above temperature.

In accordance with one aspect of the present invention, an eyelid assembly in a continuous ink jet printhead is provided for the eyelid to capture fluid and direct fluid flow through the throat of the catcher, the eyelid being mounted on the eyelid, A heater element for preventing solidification of the fluid.

Accordingly, it is an object of the present invention to prevent the liquid from solidifying on the surface of the printhead eyelid.
It is another object of the present invention to incorporate a heater element into the eyelid seal assembly to maintain the surface temperature of the eyelid above the local ambient air temperature. An advantage of the present invention is that power requirements (required power) can be minimized by molding the heater into the eyelid seal.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, FIG. 1 shows an eyelid apparatus of a continuous ink jet printing apparatus. The eyelid device 1 has an actuator portion 1a and a sealing element 1b. When starting a printing operation that allows the ejection of print droplets from the print head 10, the actuator part 1a opens. During the start-up operation of the printing device, the eyelid seal 1b traps the fluid and directs the fluid flow 2d through the throat 2a of the trap, as shown in FIG. The starting operation forms the ink jet 3 from the droplet generator 4, dries the high voltage electrode 2b, and generates a charge voltage. After the charging voltage has been supplied, the eyelid can be opened at any time. Typically, the eyelids remain closed during standby, during loading of printing paper, during printing interruptions by the operator, and during other normal interruptions. When the lid is closed, it protects the printing paper and equipment below the printhead, even if the jet is bent or a printhead error occurs that is not automatically detected.

[0013] Printheads have been configured to reduce the rate of evaporation to minimize changes in ink density in the printing device. However, such an arrangement reduces the airflow through the trap to a minimum. As the air flow in the trap decreases, air cannot be completely removed from the area 5 around the ink jet when the lid is closed, due to local evaporation of the ink from the ink droplets (not removed). 2.) The air is saturated, bringing the temperature of the air closer to the temperature of the ink (5-10 ° C.) above the temperature of the eyelid seal. As a result, the saturated air solidifies on the eyelid (particularly, on the surface 1c in FIG. 2). As coagulation proceeds, the volume of the liquid increases and drips from the eyelid, adversely affecting the high voltage electrode.

According to the present invention, the heater 6 is provided on the eye lid to prevent solidification on the surface of the eye lid (particularly, on the surface 1c which is parallel to the capture surface and collides with the ink droplets). In a preferred embodiment of the present invention, the heater 6
Is a flexible circuit with a heater element 6b on one side, a flange located on the top surface, extending beyond the part to be molded, and a flange for fixing the flexible circuit in the correct position in the mold cavity during molding. , An electrical connection portion 6a.

An eyelid assembly 1 having an actuator portion 1a and an eyelid seal 1b seals the printhead when the printhead is inactive and prevents drying of the ink in the capture surface area, or ink drip from the jet. Prevent it from falling. Preferably, the seal 1b is an eyelid seal made of silicone rubber. The heater element 6 is integrated with the eyelid seal 1 b in order to maintain the surface temperature of the eyelid at or above the local air temperature and prevent solidification on the eyelid 1. Molding the heater element in the eyelid seal also has the effect of minimizing power requirements (required power). Molding reduces power requirements by eliminating energy consumed by heating the actuator section. The actuator part made of aluminum conducts heat very well (because aluminum has high thermal conductivity),
Seals made of silicone rubber do not conduct much heat (since silicone rubber has low thermal conductivity). Unlike the case where the heater is molded in the seal as in the present invention, when the heater 6 is located outside the silicon, the energy passes through the surface facing the silicon, passes through the silicon, and is heated on the surface to be heated. Must be reached. In this case, the power requirement increases from 1.5 W to 6 to 10 W.

In a preferred embodiment of the present invention,
The integral eyelid and heater assembly has an integral connector 6a that allows the eyelid to be easily removed for maintenance or the like.

The availability and effects the present invention on the industry is useful in the field of ink jet printing, provides the advantage that coagulation on the surface of the eyelid of the print head can be prevented. Another advantage of the present invention is that by forming the heater element integrally within the eyelid seal assembly, the surface temperature of the eyelid can be maintained above the local ambient air temperature. Also, an advantage of the present invention is that the heater can be molded into the eyelid seal to minimize power requirements.

Although the present invention has been described with reference to the preferred embodiment, it goes without saying that various modifications and variations are possible within the spirit of the present invention.

[Brief description of the drawings]

FIG. 1 is a side view of a print head of a continuous ink jet printing apparatus including an eyelid assembly according to the present invention having an eyelid and an eyelid heater.

FIG. 2 is a perspective view of the eyelid and catcher assembly of the printhead of FIG. 1 showing ink flow and solidification.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Irid apparatus 1a Actuator part 1b Sealing element 2a Throat part of trap 6 Heater 6a Electrical connection part 6b Heater element 10 Print head

Claims (5)

[Claims] 1. An eyelid assembly for a continuous ink jet printhead, comprising: an eyelid for permitting print droplets to be ejected from the printhead; and an associated eyelid for capturing fluid and passing fluid through a throat of a catcher. An eyelid assembly comprising: an eyelid seal for directing flow; and a heater integral with the eyelid seal and for preventing solidification of fluid on the eyelid. 2. The eyelid assembly according to claim 1, wherein said eyelid seal is a silicon rubber eyelid seal. 3. The heater according to claim 1, wherein the heater includes a flexible circuit having a flexible circuit surface, a heater element positioned on the flexible circuit surface, a flange for fixing the flexible circuit in place, and an electrical connection portion. The eyelid assembly according to claim 1, comprising: 4. The eyelid assembly of claim 3 wherein said heater element maintains the temperature of said flexible circuit surface at a temperature of about 5 ° C. above local ambient temperature. 5. The heater element according to claim 3, wherein the heater element is molded in the eyelid seal.
Eyelid assembly.