Patent US3904156A successfully refreshed from Google Patents.
US3904156A
Expired / Lapsed
US
⏱️ 0.0 years remaining
External load stabilization apparatus
Assignee: United States Department of the Army
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Filing: 1974-07-11
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Granted: 1975-09-09
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Expires: 1994-07-11
Abstract
Abstract In the history of helicopters and similar aircraft carrying cargo externally, a need has been established for an effective load stabilization system. The apparatus provided herein not only improves external load modal damping, provides the pilot command control augmentation of the load, and minimizes pilot induced oscillation, but is universally adaptable to a wide variety of helicopters. The apparatus contemplates rigid pendants which damp load motion in response to a sensor.
Inventors
- 👤 James H Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 08:35
CPC Classifications
B; B64; B64D; B64D1/00; B64D1/22; B66; B66C; B66C13/00; B66C13/04; B66C13/06; G; G05; G05D; G05D1/00; G05D1/08; G05D1/0808; G05D1/0858
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
269 words
A stabilization mechanism for cargo load carriers of the type which are suspended beneath an aircraft by means of risers, comprising: load-carrying arm support means positioned in the base of the aircraft; a pair of retractable load-carrying arms (load arms); universal joint means positioned within the load arm support means, and adapted to receive the upper ends of each load arm so that the two load arms become pivotally connected spaced pendants; load arm drive means adapted to move each load arm within its universal joint means both longitudinally and laterally relative to the aircraft; riser attachment means pivotally connected to the lower end of each load arm and adapted to receive and move linearly with a riser attached both thereto and to the load carrier; sensor means engaging each load arm for sensing motion of the load arm relative to a reference line through the aircraft base, and for generating a signal as a function of said motion; sensor means engaging each riser attachment means for sensing motion of the risers relative to their respective load arms, and for generating a signal as a function of said motion; load arm actuating means adapted to engage and to operate each load arm drive means to move the load arms both longitudinally and laterally; electronic circuit means responsive to the load arm engaging sensor means and the riser engaging sensor means, transmitting corrective electrical signals to each load arm actuating means, driving the load arms to damp pendular load motion; and yaw damping means inhibiting oscillation of a load about a vertical axis through differential front and rear arm motion.
Claim 2
Dependent Claim
269 words
A stabilization mechanism for cargo load carriers of the type which are suspended beneath an aircraft by means of risers, comprising: load-carrying arm support means positioned in the base of the aircraft; a pair of retractable load-carrying arms (load arms); universal joint means positioned within the load arm support means, and adapted to receive the upper ends of each load arm so that the two load arms become pivotally connected spaced pendants; load arm drive means adapted to move each load arm within its universal joint means both longitudinally and laterally relative to the aircraft; riser attachment means pivotally connected to the lower end of each load arm and adapted to receive and move linearly with a riser attached both thereto and to the load carrier; sensor means engaging each load arm for sensing motion of the load arm relative to a reference line through the aircraft base, and for generating a signal as a function of said motion; sensor means engaging each riser attachment means for sensing motion of the risers relative to their respective load arms, and for generating a signal as a function of said motion; load arm actuating means adapted to engage and to operate each load arm drive means to move the load arms both longitudinally and laterally; electronic circuit means responsive to the load arm engaging sensor means and the riser engaging sensor means, transmitting corrective electrical signals to each load arm actuating means, driving the load arms to damp pendular load motion; and yaw damping means inhibiting oscillation of a load about a vertical axis through differential front and rear arm motion.
Claim 3
Dependent Claim
18 words
The mechanism of claim 1 wherein the load arm sensor means and riser sensor means sense the angles.
Claim 4
Dependent Claim
23 words
The mechanism of claim 1 wherein the load arm sensor means and riser sensor means sense the rates of change of the angles.
Claim 5
Dependent Claim
35 words
The mechanism of claim 1 wherein the electronic circuit means includes a lag filter having a transfer characteristic proportional to 1/( Tau S+1) where S is the Laplacian operator and Tau is the time constant.
Claim 6
Dependent Claim
18 words
The mechanism of claim 1 wherein the load arm support means is a load beam carrying the pendants.
Claim 7
Dependent Claim
23 words
The mechanism of claim 1 wherein the universal joint means is a pillow-block type universal joint carried by the load arm support means.
Claim 8
Dependent Claim
13 words
The mechanism of claim 1 wherein the riser attachment means are cargo hooks.
Claim 9
Dependent Claim
11 words
The mechanism of claim 1 wherein the risers are metal rods.
Claim 10
Dependent Claim
29 words
The mechanism of claim 1 wherein arms rather than being load carrying are control arms which carry the sensor means and move load carrying risers to damp the load.
Claim 11
Dependent Claim
12 words
The mechanism of claim 1 wherein the load carrier is a sling.
Claim 12
Dependent Claim
12 words
The mechanism of claim 1 wherein load carrier is a cubical container.
Claim 13
Dependent Claim
37 words
The mechanism of claim 1 wherein the load arm drive means is a piston operated actuating rod, and wherein the load arm actuating means is an electrohydrualic valve and cylinder combination whose piston operates the actuating rod.
Claim 14
Dependent Claim
17 words
The mechanism of claim 12 wherein the electrohydraulic valve and cylinder combination includes a bypass relief valve.
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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) | 1978-09-08 | 1979-03-10 | 1979-09-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-08 | 1983-03-10 | 1983-09-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-08 | 1987-03-10 | 1987-09-09 | $7700.00 | Window Closed / Lapsed |