Patent US3749515A successfully refreshed from Google Patents.
US3749515A
Expired / Lapsed
US
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Powered folding mechanism
Assignee: Bell Helicopter Textron Inc
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Filing: 1971-06-01
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Granted: 1973-07-31
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Expires: 1991-06-01
Abstract
Abstract A powered folding mechanism includes a locking pin for normally retaining a blade of a rotary wing aircraft in an extended position relative to a blade grip and a cam for rotation in one direction to first withdraw the locking pin and then fold the blade and for rotation in the opposite direction to first return the blade to the extended position and then re-engage the locking pin. Two embodiments of the powdered folding mechanism are disclosed, one of which operates directly on the blade and the other of which operates by means of a drag link connected between the grip and the blade.
Inventors
- 👤 Cecil Edward Covington
- 👤 Joe Dan Puckett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:47
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/32; B64C27/46; B64C27/473; B64C27/50
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
180 words
In a rotary wing aircraft, a blade folding mechanism comprising: an inboard blade grip; an outboard blade; means interconnecting the outboard end of the grip and the inboard end of the blade and supporting the blade for pivotal movement relative to the grip about a predetermined axis; a locking pin supported for pivotal movement with the blade and for sliding movement with respect thereto; means mounted on the grip for noRmally receiving the locking pin and thereby retaining the blade in an extended position relative to the grip; and camming means mounted on the grip for rotation in one direction about said predetermined axis to first disengage the locking pin from the pin receiving means and then to pivot the blade about said axis to a folded position relative to the grip and thereafter for rotation in the opposite direction about said axis to first pivot the blade about said axis to the extended position relative to the grip and then to engage the locking pin with the locking pin receiving means to retain the blade in the extended position.
Claim 2
Dependent Claim
180 words
In a rotary wing aircraft, a blade folding mechanism comprising: an inboard blade grip; an outboard blade; means interconnecting the outboard end of the grip and the inboard end of the blade and supporting the blade for pivotal movement relative to the grip about a predetermined axis; a locking pin supported for pivotal movement with the blade and for sliding movement with respect thereto; means mounted on the grip for noRmally receiving the locking pin and thereby retaining the blade in an extended position relative to the grip; and camming means mounted on the grip for rotation in one direction about said predetermined axis to first disengage the locking pin from the pin receiving means and then to pivot the blade about said axis to a folded position relative to the grip and thereafter for rotation in the opposite direction about said axis to first pivot the blade about said axis to the extended position relative to the grip and then to engage the locking pin with the locking pin receiving means to retain the blade in the extended position.
Claim 3
Dependent Claim
48 words
The blade folding mechanism according to claim 1 wherein the camming means further includes pin and slot means interconnecting the locking pin and the camming means and responsive to rotation of the cam for sliding the locking pin in and out of engagement with the pin receiving means.
Claim 4
Dependent Claim
54 words
The blade folding mechanism according to claim 2 further including a latching surface formed on the camming means, a pawl attached to the blade for rotation therewith, and means responsive to rotation of the blade away from the extended position for latching the pawl into engagement with the latching surface on the camming means
Claim 5
Dependent Claim
84 words
The blade folding mechanism according to claim 3 wherein the pawl latching means comprises a cam mounted on the blade grip, a cam follower supported for rotation with the blade and positioned for engagement with the cam on the grip in response to rotation of the blade away from the extended position, and cooperating surfaces on the cam follower and the pawl for retaining the pawl in engagement with the latching surface whenever the cam follower is engaged with the cam on the grip.
Claim 6
Dependent Claim
178 words
Apparatus for folding a blade of a rotary wing aircraft which comprises: a blade grip; a blade supported on the blade grip for pivotal movement about a predetermined axis; a latching pin supported on the blade for reciprocation with respect thereto and for pivotal movement with the blade relative to the grip; means mounted on the grip for normally receiving the latching pin and thereby securing the blade in an extended position relative to the grip; and a member supported for rotation in one direction about said predetermined axis first relative both to the blade and to the grip to disengage the locking pin from the receiving means and then for engagement and rotation with the blade relative to the grip to pivot the blade to a folded position relative to the grip and for rotation in the opposite direction about said predetermined axis first with the blade relative to the grip to return the blade to the extended position and then relative to the blade and the grip to engage the locking pin with the retaining means.
Claim 7
Dependent Claim
178 words
Apparatus for folding a blade of a rotary wing aircraft which comprises: a blade grip; a blade supported on the blade grip for pivotal movement about a predetermined axis; a latching pin supported on the blade for reciprocation with respect thereto and for pivotal movement with the blade relative to the grip; means mounted on the grip for normally receiving the latching pin and thereby securing the blade in an extended position relative to the grip; and a member supported for rotation in one direction about said predetermined axis first relative both to the blade and to the grip to disengage the locking pin from the receiving means and then for engagement and rotation with the blade relative to the grip to pivot the blade to a folded position relative to the grip and for rotation in the opposite direction about said predetermined axis first with the blade relative to the grip to return the blade to the extended position and then relative to the blade and the grip to engage the locking pin with the retaining means.
Claim 8
Dependent Claim
68 words
The blade folding apparatus according to claim 5 further characterized by: means for latching the blade to the rotating member and thereby assuring pivotal movement of the blade to the extended position upon rotation of the member in said opposite direction about said predetermined axis; and means responsive to pivotal movement of the blade out of the extended position relative to the grip for actuating the latching means.
Claim 9
Dependent Claim
70 words
The blade folding apparatus according to claim 6 wherein the latching means comprises a latching surface on the rotating member and a cooperating latching member mounted on the blade and wherein the actuating means comprises cooperating camming means on the blade and on the grip for securing the latching member in engagement with the latching surface whenever the blade is pivoted out of the extended position relative to the grip.
Claim 10
Dependent Claim
79 words
The blade folding apparatus according to claim 5 wherein the latching pin is connected to the rotating member by pin and slot means responsive to rotation of the member in one direction relative to the grip and the blade to disengage the latching pin from the latching pin receiving means and responsive to rotation of the member in an opposite direction relative to the blade and the grip to engage the latching pin with the latching pin receiving means.
Claim 11
Dependent Claim
58 words
The blade folding apparatus according to claim 5 wherein the outboard end of the grip and the inboard end of the blade comprise bifurcated portions which are interleaved at said predetermined axis and defining an open space therebetween, and wherein the rotating member is positioned within the open space between the bifurcations of the blade and the grip.
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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) | 1976-07-30 | 1977-01-29 | 1977-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-30 | 1981-01-29 | 1981-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-30 | 1985-01-29 | 1985-07-31 | $7700.00 | Window Closed / Lapsed |