Incremental printing of symbolic information – Ink jet – Ejector mechanism
Reexamination Certificate
1998-03-13
2001-08-07
Tran, Huan (Department: 2861)
Incremental printing of symbolic information
Ink jet
Ejector mechanism
Reexamination Certificate
active
06270204
ABSTRACT:
BACKGROUND OF THE INVENTION
The invention relates to an ink pen assembly of a continuous ink jet printer.
As described in Jochimsen, U.S. Pat. No. 4,639,736, titled INK JET RECORDER, incorporated by reference herein, continuous ink jet printers produce a continuous stream of ink drops directed at a substrate. The ink drops include printing and non-printing drops. The ink drops are selectively charged such that the non-printing drops are deflected to prevent the non-printing drops from reaching the substrate.
A removable nozzle unit including a charging tunnel for producing a continuous stream of ink drops and charging the non-printing drops is described in Fargo et al., U.S. Pat. No. 5,160,938, titled METHOD AND MEANS FOR CALIBRATING AN INK JET PRINTER, incorporated by reference herein.
SUMMARY OF THE INVENTION
According to one aspect of the invention, an ink pen cartridge is removably received within a printhead nest of a continuous ink jet printer. The ink pen cartridge includes a pen body configured to be placed in electrical communication with the printhead nest, and a nozzle body which defines an inlet configured to be placed in fluid communication with the printhead nest to receive ink from the printhead nest. The nozzle body also has an outlet through which ink is jetted.
A charge electrode charges ink drops breaking off from the ink jetted from the nozzle body outlet. A deflection electrode deflects the charged ink drops. The deflection electrode is configured and arranged such that charged ink drops are deflected along an axis substantially transverse to a direction of travel of a substrate to be printed.
Embodiments of this aspect of the invention may includes one or more of the following features.
An ink block mount is connected to the pen body and includes an ink blocking element for diverting deflected ink drops. An ink block actuator configured to be placed in mechanical communication with the printhead nest is used to adjust the position of the ink blocking element. The ink block actuator is mounted to the pen body to pivot with respect to the pen body.
The nozzle body houses a tube through which ink flows. A transducer is mounted to the tube for synchronizing breakup of ink jetted from the nozzle body outlet into ink drops.
The pen body defines an ink drain for draining ink from the pen body to the printhead nest. A mist bib formed from, e.g, acid-etched stainless steel, is mounted to the pen body for collecting spray produced when ink droplets contact a substrate.
An electrical connection board is mounted to the pen body for providing the electrical communication with the printhead nest.
In certain embodiments, the pen body includes a barrier plate defining a drop charging chamber. The charge tunnel and deflection electrodes are located within the drop charging chamber and spaced from the barrier plate. The barrier plate is inclined with respect to a side wall of the drop charging chamber.
According to another aspect of the invention, an ink pen cartridge removably received within a printhead nest of a continuous ink jet printer includes a pen body, a nozzle body, a deflection electrode, and an ink block actuator configured to be placed in mechanical communication with the printhead nest. Movement of the ink block actuator relative to the pen body adjusts the position of an ink blocking element.
Embodiments of this aspect of the invention may includes one or more of the following features.
A charge electrode charges ink drops breaking off from the ink jetted from the nozzle body outlet. An ink block mount includes the ink blocking element for diverting the deflected ink drops.
According to another aspect of the invention, an ink jet nozzle includes a nozzle body defining an ink passage and a vacuum passage. A jet housing is located within the ink passage. A tube is located within a through bore of the jet housing. An outlet of the vacuum passage is in fluid communication with an outlet end of the tube. An ink passage inlet and a vacuum passage inlet are defined in a single sealing face of the nozzle body.
Embodiments of this aspect of the invention may includes one or more of the following features.
An ink passage seal is located at the inlet of the ink passage, and a vacuum passage seal is located at the inlet of the vacuum passage.
A transducer is mounted to the tube for synchronizing breakup of a jet of ink from the tube outlet into ink drops. A first spring abuts the transducer on an upstream side of the transducer, and a second spring abuts the transducer on a downstream side of the transducer. The first and second springs locate the transducer with respect to the tube prior to fixing the transducer to the tube. The second spring is connected to a ground plane of the transducer to act as a shield.
The tube comprises a capillary tube having an inner diameter of about 100 microns. The inner diameter is reduced to about 10 microns at the outlet end of the tube. A filter is located at the inlet end of the tube.
According to another aspect of the invention, a printhead nest for receiving an ink pen cartridge includes a housing defining an ink outlet for providing ink to the ink pen cartridge, a mechanical link for interfacing with the ink pen cartridge to adjust the position of an ink blocking element of the ink pen cartridge, and an electrical connection for interfacing with the ink pen cartridge to control a deflection electrode of the ink pen cartridge.
Embodiments of this aspect of the invention may includes one or more of the following features.
A fluid catcher receives ink that drains from the ink pen cartridge. The housing defines four ink outlets, four mechanical links, and four electrical connections. The ink outlets provide ink to four ink pen cartridge. The mechanical links and electrical connections each interface with one of the four ink pen cartridges.
According to another aspect of the invention, an ink pen assembly includes an ink pen cartridge and a printhead nest. The ink pen cartridge includes a pen body, a nozzle body, a charge electrode, and a deflection electrode. The printhead nest includes a housing defining an ink outlet for providing ink to an inlet of the nozzle body, and an electrical connection for interfacing with the pen body to control the charge tunnel and deflection electrodes. The ink pen is configured for placement in the printhead nest and removal from the printhead nest as a single unit.
According to another aspect of the invention a continuous ink jet printer includes a printhead nest defining at least four ink outlets. The printhead nest is configured to deliver a different colored ink through each of four ink outlets. At least four ink pen cartridges are removably received by the printhead nest. Each ink pen cartridge defines an ink inlet aligned with one of the ink outlets for receiving ink from the printhead nest when the ink pen cartridges are received by the printhead nest. Each ink pen cartridge also includes a charge electrode for charging ink drops breaking off from the received ink, and a deflection electrode for deflecting charged ink drops. Each deflection electrode is configured and arranged such that charged ink drops are deflected along an axis substantially transverse to a direction of travel of a substrate to be printed. The charge electrode is adjustable to impart varying levels of charge to the ink drops such that different ink drops are deflected by different amounts by the deflection electrode to facilitate registration of the ink drops from the at least four ink pen cartridges on a substrate.
Advantages of the invention includes a disposable ink pen cartridge which includes all of the components of a continuous ink jet printhead, e.g., the drop producing, drop charging, and drop deflecting elements, which are likely to fail. The ink pen cartridge can be quickly removed and disposed of and replaced with a new cartridge. The failed cartridge can be replaced even while the continuous ink jet printer remains turned on.
Other features and advantages of the invention will be apparent from the following de
Barrett Douglas J.
Dolan Matthew
Gomez Carlos A.
Hagerty Thomas
Fish & Richardson P.C.
Iris Graphics Inc.
Nghiem Michael
Tran Huan
LandOfFree
Ink pen assembly does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ink pen assembly, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ink pen assembly will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2531169