US3791230A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pressure operated indexing mechanism
Assignee: Avco Corp
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Filing: 1972-06-23
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Granted: 1974-02-12
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Expires: 1992-06-23
Abstract
Abstract A pressure operated indexing mechanism to provide remote indexing of a mechanism through the use of fluid pressure pulses is disclosed. The device provides a means where a munition or other device can be indexed or set while in a closed container. A pair of telescoping pistons are acted on by externally applied pressure. The primary piston will advance the mechanism one position for each pulse of a predetermined pressure. Pressures higher than another and greater predetermined pressure will cause the secondary piston to cause the mechanism to reset to the start or safe position.
Inventors
- 👤 G Webb
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:48
CPC Classifications
F; F42; F42B; F42B35/00; F42B35/02; Y; Y10; Y10T; Y10T74/00; Y10T74/15; Y10T74/1526; Y10T74/1529
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
235 words
A fluid pressure operated indexing mechanism for progressive indexing a given pressure and resetting at a higher pressure comprising: a housing having a bore therethrough, said bore communicating with a chamber defined by said housing; a ratchet pivotally mounted in the chamber, said ratchet being normally biased to an initial position; a drive pawl for cooperative engagement with said ratchet; a lock pawl mounted on said housing for cooperative engagement with said ratchet; first and second concentric pressure responsive pistons mounted for slidable movement in said bore, said pistons being jointly responsive to the given indexing pressure, said drive pawl being pivotally connected with said second piston wherein axial movement of said first and second pistons along said bore in response to the given pressure will cause said drive pawl to engage said ratchet whereby said ratchet will be incrementally indexed in response to the given pressure and retained in the indexed position by said lock pawl, said second pressure responsive piston being mounted for slidable movement in a bore in said first piston and being responsive to a higher pressure than said given pressure thereby causing said lock pawl and said drive pawl to disengage said ratchet and permit said ratchet to be biased to its initial position; and means for moving said first and second pistons in said bore to an initial position in the absence of pressure being applied to said pistons.
Claim 2
Dependent Claim
235 words
A fluid pressure operated indexing mechanism for progressive indexing a given pressure and resetting at a higher pressure comprising: a housing having a bore therethrough, said bore communicating with a chamber defined by said housing; a ratchet pivotally mounted in the chamber, said ratchet being normally biased to an initial position; a drive pawl for cooperative engagement with said ratchet; a lock pawl mounted on said housing for cooperative engagement with said ratchet; first and second concentric pressure responsive pistons mounted for slidable movement in said bore, said pistons being jointly responsive to the given indexing pressure, said drive pawl being pivotally connected with said second piston wherein axial movement of said first and second pistons along said bore in response to the given pressure will cause said drive pawl to engage said ratchet whereby said ratchet will be incrementally indexed in response to the given pressure and retained in the indexed position by said lock pawl, said second pressure responsive piston being mounted for slidable movement in a bore in said first piston and being responsive to a higher pressure than said given pressure thereby causing said lock pawl and said drive pawl to disengage said ratchet and permit said ratchet to be biased to its initial position; and means for moving said first and second pistons in said bore to an initial position in the absence of pressure being applied to said pistons.
Claim 3
Dependent Claim
69 words
An indexing mechanism as set forth in claim 1 further comprising inertial safety means responsive to high inertial loads which simulate sufficient pressure to cause movement of said first and second pistons in said bore to disengage said drive pawl from said ratchet whereby incremental indexing of said ratchet is prevented due to movement of said first and second pistons in the bore due to the high inertial loads.
Claim 4
Dependent Claim
158 words
An indexing mechanism as set forth in claim 1 further comprising: first and second shoulders in the bore for respectively engaging said first and second piston to limit the axial movement of each of said pistons wherein the given pressure acting on said first and second pistons will cause said pistons to move in the bore until stopped by said first shoulder whereby said ratchet is indexed one increment due to the movement of said pistons and wherein pressure at the higher pressure applied to said pistons will move said second piston along said bore to said second shoulder, said secondary piston movement causing continued axial movement of said drive pawl; and further comprising means for imparting a rotational movement to said drive pawl in response to said continued movement of said second piston wherein said drive pawl is disengaged from said ratchet thereby preventing indexing of said ratchet due to the continued movement of said second piston.
Claim 5
Dependent Claim
89 words
An indexing mechanism as set forth in claim 3 in which said lock means is a lock pawl engageable with said ratchet, said lock pawl and said drive pawl moving in parallel planes, said lock pawl having a transverse tab formed thereon wherein said drive pawl engages said transverse tab during rotational movement of said drive pawl wherein said lock pawl is disengaged from said ratchet in unison with said drive pawl in response to movement of said second piston whereby said ratchet can return to the initial position.
Claim 6
Dependent Claim
69 words
An indexing mechanism as set forth in claim 4 further comprising inertial safety means responsive to high inertial loads which simulate sufficient pressure to cause movement of said first and second pistons in said bore to disengage said drive pawl from said ratchet whereby incremental indexing of said ratchet is prevented due to movement of said first and second pistons in the bore due to the high inertial loads.
Claim 7
Dependent Claim
65 words
An indexing mechanism as set forth in claim 5 in which said inertial safety means is a pendulous mass connected with said drive pawl wherein inertial loads imparted to the mechanism will cause said mass to have a rotational movement thereby rotationally moving said drive pawl to uncouple said drive pawl from said ratchet thereby preventing indexing of said ratchet in response to inertial loads.
Claim 8
Dependent Claim
44 words
An indexing mechanism as set forth in claim 6 further comprising a closure member mounted in said bore, said closure member being provided with a plurality of apertures wherein pressure applied externally of said closure member is transmitted to said pistons in the bore.
Claim 9
Dependent Claim
44 words
An indexing mechanism as set forth in claim 7 in which the area of said firsT and second piston is the same and in which said means for moving said pistons is a spring mounted in the bore and acting against said second piston.
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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) | 1977-02-11 | 1977-08-13 | 1978-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-11 | 1981-08-13 | 1982-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-11 | 1985-08-13 | 1986-02-12 | $7700.00 | Window Closed / Lapsed |