EP0437363A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Pressure-sensitive accumulator for ink-jet pens
Assignee: HP Inc
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Filing: 1991-01-10
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Granted: —
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Expires: 2011-01-10
Abstract
Abstract The accumulator (20) regulates changes in the back pressure of an ink-jet pen (22) reservoir (24) so that ink does not leak from the pen print head (36) and so that the print head (36) is able to completely empty the reservoir (24) of ink. The accumulator (20) includes a flexible bag (42) that is mounted to a flat curved spring (44). The elasticity of the spring (44) tends to contract the bag (42) as the bag (42) expands in response to back pressure reduction in the reservoir (24).
Inventors
- 👤 Bruce Cowger
- 👤 Marc A. Baldwin
- 👤 Fred E. Tarver
- 👤 Gary D. Tarver
- 👤 George M. Custer
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 07:54
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/015; B41J2/02; B41J2/03; B41J2/17; B41J2/175; B41J2/17503; B41J2/17556; B41J2/17506; B41J2/17513
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
55 words
An accumulator apparatus comprising: an expandable and contractable bag (42); and mounting means (46) for mounting the bag (42) within a fluid volume (24) so that expansion of the bag (42) decreases the size of the fluid volume, the bag (42) being arranged to be in fluid communication with fluid outside the fluid volume (24).
Claim 2
Dependent Claim
19 words
An apparatus according to claim 1 further comprising elastic means (44) for urging the bag toward a contracted state.
Claim 3
Dependent Claim
26 words
An apparatus according to claim 2 wherein the elastic means (44) includes a spring (44) arranged so that expansion of the bag deflects the spring (44).
Claim 4
Dependent Claim
35 words
An apparatus according to claim 3 wherein the spring (44) and bag (42) are configured and arranged so that the bag (42) is substantially fully contracted when the spring (44) is in a relaxed state.
Claim 5
Dependent Claim
35 words
An apparatus according to claim 4 wherein the spring (44) includes a first portion (62) that assumes a curved relaxed state, the bag (42) being fastened to one side (64) of the curved first portion.
Claim 6
Dependent Claim
40 words
An apparatus according to claim 5 wherein the first portion (62) of the spring (44) has a convex surface (64) whenever the first portion (62) is in a relaxed state, the bag (42) being fastened to the convex surface (64).
Claim 7
Independent Claim
30 words
An apparatus according to any of claims 3 to 6 wherein the spring (44) is metal and the bag (42) is formed of flexible material having a plastic outer surface.
Claim 8
Independent Claim
28 words
An apparatus according to any of claims 3 to 7 wherein the spring (44) has a flat base (52) connected to the first portion (62) of the spring.
Claim 9
Dependent Claim
55 words
An apparatus according to claim 8 wherein the spring (44) includes a second portion (62) connected to the base (52), the second portion (62) assuming a curved relaxed state, the bag (42) being fastened to one side (64) of the second portion (62) and to one side of the base (52) of the spring (44).
Claim 10
Dependent Claim
34 words
An apparatus according to claim 5 wherein the spring (44) includes a second portion (62) that assumes a curved relaxed state, the bag being fastened to one side (64) of the curved second portion.
Claim 11
Independent Claim
17 words
An apparatus according to any of claims 7 to 10 wherein the spring (44) is stainless steel.
Claim 12
Independent Claim
30 words
An apparatus according to any of claims 1 to 11 wherein the bag (42) is formed of sheets (76,77) of flexible material and is contractable into a generally flat configuration.
Claim 13
Dependent Claim
16 words
An apparatus according to claim 12 wherein the bag sheets (76,77) are formed of heat-weldable material.
Claim 14
Dependent Claim
22 words
An apparatus according to claim 13 wherein the bag sheets (76,77) include means for rendering the bag sheets substantially impermeable to air.
Claim 15
Independent Claim
79 words
A method for making an accumulator apparatus, comprising the steps of: ― attaching an expandable and contractable bag (42) to a spring (44) so that when the spring (44) is in a relaxed state the bag (42) will be substantially contracted; and configuring the bag (42) and spring (44) so that the bag (42) will expand and deflect the spring (44) whenever the pressure difference between the fluid inside and outside of the bag exceeds a predetermined minimum level.
Claim 16
Dependent Claim
29 words
A method according to claim 15 wherein the configuring step includes the substep of shaping the spring (44) to have a curved portion (62) when in a relaxed state.
Claim 17
Dependent Claim
27 words
A method according to claim 16 wherein the attaching step includes the substep of fastening the bag (42) to the curved portion (62) of the spring (44).
Claim 18
Independent Claim
52 words
A method according to any of claims 15 to 17 wherein the spring (44) is metal and wherein the bag (42) has a plastic outer surface, the attaching step including the substep of forming access holes (71,72,74) in the spring (44) for providing locations for attaching the bag (42) to the spring.
Claim 19
Independent Claim
65 words
A method according to any of claims 15 to 18 wherein the accumulator is to be disposed within a fluid volume (24) that may be subjected to a decrease in pressure, the configuring step including the step of sizing the bag to define a working volume that is equal to or greater than the change in the fluid volume attributable to the decrease in pressure.
References Cited (Backward Citations)
No citation records indexed.
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