US4403229A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Maintenance system to prime and to exclude air from ink jet heads
Assignee: International Business Machines Corp
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Filing: 1981-10-30
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Granted: 1983-09-06
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Expires: 2001-10-30
Abstract
Abstract The ingestion of air into the print head of an ink jet printer is controlled by a secondary fluidic system. The secondary fluidic system interconnects the ink supply cavity of the head with the primary fluidic system of the printer. The secondary fluidic system includes a valve which is coupled to a venting port of the print head. A rapid decompression regulator is coupled to the valve. The exit port of the regulator is attached to one end of a conduit. The other end of the conduit is disposed in a fluid-containing reservoir. The reservoir serves as an expansion/contraction chamber and keeps air from entering the head even under extreme thermocycling conditions. Likewise, the regulator controls the pressure in the head so that head pressure (P h ) is greater than or equal to ambient pressure P a . This pressure differential prevents air from entering the head.
Inventors
- 👤 Joseph C. Barteck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 06:24
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/17; B41J2/175
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
227 words
In an ink jet printing device wherein pressurized ink is supplied to a print head cavity having a supply chamber and settling chamber and ink is expelled through one or more minute openings in the supply chamber to print indicia on a recording surface, an apparatus for preventing the entry of air into the supply chamber, said apparatus comprising: an inlet port and an outlet port in the settling chamber; a valve assembly means for opening said inlet port to convey pressurized ink into the cavity and for opening said outlet port to convey pressurized ink out of the cavity; a rapid decompression regulator having an entry port and an exit port, said entry port coupled to the outlet port of the settling chamber; said decompression regulator operable to control ink flow out of the cavity so that the head cavity decompressed first at a rapid rate and subsequently at a slower controlled rate; and an ink reservoir vented to atmospheric pressure, coupled to the exit port of said regulator and operable to draw ink from the cavity when said valve assembly means opens said outlet port and closes said inlet port; the ink being drawn out of the cavity until ink in the cavity is near atmospheric pressure and capillary action establishes a volume of ink in each opening thereby blocking air from entering the cavity.
Claim 2
Dependent Claim
227 words
In an ink jet printing device wherein pressurized ink is supplied to a print head cavity having a supply chamber and settling chamber and ink is expelled through one or more minute openings in the supply chamber to print indicia on a recording surface, an apparatus for preventing the entry of air into the supply chamber, said apparatus comprising: an inlet port and an outlet port in the settling chamber; a valve assembly means for opening said inlet port to convey pressurized ink into the cavity and for opening said outlet port to convey pressurized ink out of the cavity; a rapid decompression regulator having an entry port and an exit port, said entry port coupled to the outlet port of the settling chamber; said decompression regulator operable to control ink flow out of the cavity so that the head cavity decompressed first at a rapid rate and subsequently at a slower controlled rate; and an ink reservoir vented to atmospheric pressure, coupled to the exit port of said regulator and operable to draw ink from the cavity when said valve assembly means opens said outlet port and closes said inlet port; the ink being drawn out of the cavity until ink in the cavity is near atmospheric pressure and capillary action establishes a volume of ink in each opening thereby blocking air from entering the cavity.
Claim 3
Dependent Claim
98 words
The apparatus of claim 1 and in addition: said regulator having a central chamber disposed in a general vertical orientation interconnecting the entry port and the exit port; a flow control means disposed within said central chamber and operable to be transposed by ink flow from a position next to the entry port whereat the ink flow is less restricted to a position next to the exit port whereat the ink flow is more restricted so that the ink pressure in the cavity is prevented from going below atmospheric pressure as the pressure is released through said regulator.
Claim 4
Dependent Claim
11 words
The apparatus of claim 2 wherein said central chamber is cylindrical.
Claim 5
Dependent Claim
13 words
The apparatus of claim 3 wherein said flow control means is a ball.
Claim 6
Dependent Claim
22 words
The apparatus of claim 4 further including: an adjustable stop for said ball disposed adjacent the exit port of said central chamber.
Claim 7
Dependent Claim
170 words
An improved ink jet head suitable for use with an ink jet printing system comprising: a housing having a supply chamber therein for containing a supply of ink; a nozzle plate having a plurality of nozzles therein mounted on one side of the housing and in fluidic communication with the chamber; a drive crystal associated with the chamber and operable to vibrate the chamber so that ink outputted through the nozzles is broken up into a plurality of droplets; a settling chamber disposed in the housing and in fluidic communication with the supply chamber; an ink inlet port fabricated in one end of the housing and operable to convey ink into the bottom of the settling chamber so that ink flow and gravity forces air toward the top of said chamber; a first flush port disposed at the top of the settling chamber; and a second flush port disposed on the opposite end of the housing downstream from the first flush port and in fluidic communication with the supply chamber.
Claim 8
Dependent Claim
170 words
An improved ink jet head suitable for use with an ink jet printing system comprising: a housing having a supply chamber therein for containing a supply of ink; a nozzle plate having a plurality of nozzles therein mounted on one side of the housing and in fluidic communication with the chamber; a drive crystal associated with the chamber and operable to vibrate the chamber so that ink outputted through the nozzles is broken up into a plurality of droplets; a settling chamber disposed in the housing and in fluidic communication with the supply chamber; an ink inlet port fabricated in one end of the housing and operable to convey ink into the bottom of the settling chamber so that ink flow and gravity forces air toward the top of said chamber; a first flush port disposed at the top of the settling chamber; and a second flush port disposed on the opposite end of the housing downstream from the first flush port and in fluidic communication with the supply chamber.
Claim 9
Dependent Claim
32 words
The improved ink jet head of claim 6 wherein the supply chamber is being disposed in a general horizontal orientation; and the settling chamber is being disposed in a general vertical orientation.
Claim 10
Dependent Claim
26 words
The improved ink jet head of claim 6 further including a filtering means operable to filter ink exiting from the settling chamber into the supply chamber.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-09-05 | 1987-03-07 | 1987-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-09-05 | 1991-03-07 | 1991-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-09-05 | 1995-03-07 | 1995-09-06 | $7700.00 | Window Closed / Lapsed |