US3782854A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Elastomeric bearing for a helicopter rotor
Assignee: RTX Corp
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Filing: 1972-07-05
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Granted: 1974-01-01
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Expires: 1992-07-05
Abstract
Abstract An elastomeric bearing comprising two elastomeric bearings in series connecting a helicopter blade to a helicopter rotor hub so as to be articulated and have at least three degrees of freedom, namely, flapping motion, lead-lag motion and pitch motion, and wherein said bearing occupies minimal space envelope and the two elastomeric bearings thereof share the motion in at least one of the degrees of freedom.
Inventors
- 👤 R Rybicki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:11
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/32; B64C27/35
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
380 words
An articulated helicopter rotor comprising: A. a rotatable hub member adapted to be mounted for rotation about an axis and having: 1. a chamber defining member shaped to define a blade attachment chamber and to further define a substantially circular aperture at said chamber radially outer end, and further being shaped to present a spherical surface along the inner surface thereof, which spherical surface is centered about the intersection of the blade lead-lag and flapping axes, B. blade attachment means including: 1. a shaft member positioned concentrically about the blade feathering axis and extending from within said chamber through said aperture and outwardly thereof for attachment to and support of the helicopter blade and being flange shaped at its radial inner end within said chamber, 2. bearing means connecting said shaft member to said chamber defining member and including: a. a spherical, laminated elastomeric bearing with the laminates thereof centered about said lead-lag and flapping axes intersection and being annular in shape so as to envelop said shaft member in spaced relation thereto and with the outer laminate thereof connected to said chamber defining member spherical surface to form a bearing outer race, b. a flat, laminated elastomeric bearing And being annular in shape so as to envelop said shaft in space relation thereto and comprising a plurality of stacked, flat annular discs connected to said shaft flange at one of its ends and extending toward said spherical bearing, c. a connecting member enveloping said shaft member in spaced relation thereto and positioned between said spherical elastomeric bearing and said flat elastomeric bearing and shaped at one of its ends to be spherical and centered about said flapping and lead-lag axes intersection and connected to said spherical elastomeric bearing so as to serve as the inner race thereof and being connected to said flat elastomeric bearing at the opposite end thereof so that said spherical elastomeric bearing and said flat elastomeric bearing are connected in series relationship between said shaft member and said chamber defining means and so that said spherical elastomeric bearing accommodates the blade motion about the lead-lag and the flapping axes and so that said spherical elastomeric bearing and said flat elastomeric bearing cooperate to carry blade centrifugal loading and further cooperate to share blade pitch-change motion.
Claim 2
Dependent Claim
380 words
An articulated helicopter rotor comprising: A. a rotatable hub member adapted to be mounted for rotation about an axis and having: 1. a chamber defining member shaped to define a blade attachment chamber and to further define a substantially circular aperture at said chamber radially outer end, and further being shaped to present a spherical surface along the inner surface thereof, which spherical surface is centered about the intersection of the blade lead-lag and flapping axes, B. blade attachment means including: 1. a shaft member positioned concentrically about the blade feathering axis and extending from within said chamber through said aperture and outwardly thereof for attachment to and support of the helicopter blade and being flange shaped at its radial inner end within said chamber, 2. bearing means connecting said shaft member to said chamber defining member and including: a. a spherical, laminated elastomeric bearing with the laminates thereof centered about said lead-lag and flapping axes intersection and being annular in shape so as to envelop said shaft member in spaced relation thereto and with the outer laminate thereof connected to said chamber defining member spherical surface to form a bearing outer race, b. a flat, laminated elastomeric bearing And being annular in shape so as to envelop said shaft in space relation thereto and comprising a plurality of stacked, flat annular discs connected to said shaft flange at one of its ends and extending toward said spherical bearing, c. a connecting member enveloping said shaft member in spaced relation thereto and positioned between said spherical elastomeric bearing and said flat elastomeric bearing and shaped at one of its ends to be spherical and centered about said flapping and lead-lag axes intersection and connected to said spherical elastomeric bearing so as to serve as the inner race thereof and being connected to said flat elastomeric bearing at the opposite end thereof so that said spherical elastomeric bearing and said flat elastomeric bearing are connected in series relationship between said shaft member and said chamber defining means and so that said spherical elastomeric bearing accommodates the blade motion about the lead-lag and the flapping axes and so that said spherical elastomeric bearing and said flat elastomeric bearing cooperate to carry blade centrifugal loading and further cooperate to share blade pitch-change motion.
Claim 3
Dependent Claim
254 words
bearing means connecting said shaft member to said chamber defining member and including: a. a spherical, laminated elastomeric bearing with the laminates thereof centered about said lead-lag and flapping axes intersection and being annular in shape so as to envelop said shaft member in spaced relation thereto and with the outer laminate thereof connected to said chamber defining member spherical surface to form a bearing outer race, b. a flat, laminated elastomeric bearing And being annular in shape so as to envelop said shaft in space relation thereto and comprising a plurality of stacked, flat annular discs connected to said shaft flange at one of its ends and extending toward said spherical bearing, c. a connecting member enveloping said shaft member in spaced relation thereto and positioned between said spherical elastomeric bearing and said flat elastomeric bearing and shaped at one of its ends to be spherical and centered about said flapping and lead-lag axes intersection and connected to said spherical elastomeric bearing so as to serve as the inner race thereof and being connected to said flat elastomeric bearing at the opposite end thereof so that said spherical elastomeric bearing and said flat elastomeric bearing are connected in series relationship between said shaft member and said chamber defining means and so that said spherical elastomeric bearing accommodates the blade motion about the lead-lag and the flapping axes and so that said spherical elastomeric bearing and said flat elastomeric bearing cooperate to carry blade centrifugal loading and further cooperate to share blade pitch-change motion.
Claim 4
Dependent Claim
254 words
bearing means connecting said shaft member to said chamber defining member and including: a. a spherical, laminated elastomeric bearing with the laminates thereof centered about said lead-lag and flapping axes intersection and being annular in shape so as to envelop said shaft member in spaced relation thereto and with the outer laminate thereof connected to said chamber defining member spherical surface to form a bearing outer race, b. a flat, laminated elastomeric bearing And being annular in shape so as to envelop said shaft in space relation thereto and comprising a plurality of stacked, flat annular discs connected to said shaft flange at one of its ends and extending toward said spherical bearing, c. a connecting member enveloping said shaft member in spaced relation thereto and positioned between said spherical elastomeric bearing and said flat elastomeric bearing and shaped at one of its ends to be spherical and centered about said flapping and lead-lag axes intersection and connected to said spherical elastomeric bearing so as to serve as the inner race thereof and being connected to said flat elastomeric bearing at the opposite end thereof so that said spherical elastomeric bearing and said flat elastomeric bearing are connected in series relationship between said shaft member and said chamber defining means and so that said spherical elastomeric bearing accommodates the blade motion about the lead-lag and the flapping axes and so that said spherical elastomeric bearing and said flat elastomeric bearing cooperate to carry blade centrifugal loading and further cooperate to share blade pitch-change motion.
Claim 5
Dependent Claim
34 words
A rotor according to claim 1 wherein said spherical elastomeric bearing and said flat elastomeric bearing are of selected different torsional stiffness so as to selectively share the accommodation of blade pitch change motion.
Claim 6
Dependent Claim
26 words
and annular, disc-type, laminated, elastomeric bearing having a central opening enveloping the blade feathering axis and with the disc-shaped laminates thereof lying in planes perpendicular thereto,
Claim 7
Dependent Claim
26 words
and annular, disc-type, laminated, elastomeric bearing having a central opening enveloping the blade feathering axis and with the disc-shaped laminates thereof lying in planes perpendicular thereto,
Claim 8
Dependent Claim
56 words
A rotor according to claim 1 wherein said spherical elastomeric bearing is of substantially greater torsional stiffness than is said flat elastomeric bearing so that said spherical bearing is of minimal height, so that said flat elastomeric bearing will accommodate a greater portion of pitch change motion of the blade than does the spherical elastomeric bearing.
Claim 9
Dependent Claim
16 words
means connecting said spherical and disc-type elastomeric bearings so that they are joined in series, and
Claim 10
Dependent Claim
16 words
means connecting said spherical and disc-type elastomeric bearings so that they are joined in series, and
Claim 11
Dependent Claim
66 words
A rotor according to claim 1 wherein said spherical bearing is of minimum height dimension and hence minimum space envelope and of selected torsional stiffness with respect to the torsional stiffness of said flat bearing so that said spherical bearing accommodates a minimal portion of said blade pitch change motion and said flat bearing accommodates the remainder of the required accommodation for blade pitch change motion.
Claim 12
Dependent Claim
89 words
a shaft member adapted to connect to the blade and extending along the blade feathering axIs and passing through said spherical bearing and disc-type bearing central openings and connecting at its radially inner end to said stack-type bearing so that said blade carrying shaft member is supported from said hub through said in-series bearings with freedom of motion about the blade feathering, lead-lag and flapping axes and with the spherical bearing accommodating the lead-lag and flapping motions and with the two bearings cooperating to share the pitch change motion.
Claim 13
Dependent Claim
89 words
a shaft member adapted to connect to the blade and extending along the blade feathering axIs and passing through said spherical bearing and disc-type bearing central openings and connecting at its radially inner end to said stack-type bearing so that said blade carrying shaft member is supported from said hub through said in-series bearings with freedom of motion about the blade feathering, lead-lag and flapping axes and with the spherical bearing accommodating the lead-lag and flapping motions and with the two bearings cooperating to share the pitch change motion.
Claim 14
Dependent Claim
41 words
A rotor according to claim 1 wherein said shaft member is shaped to form a reduced diameter stub-shaft at the point of connection to said damper member so as to reduce the size of said journal bearing and said elastomeric bearing.
Claim 15
Dependent Claim
54 words
A rotor according to claim 1 wherein said blade attachment means supports said shaft member and hence said blade to permit blade pitch change motion through an angle of about 60*, to permit blade lead-lag motion through an angle of about 20*, and to permit blade flapping motion through an angle of about 30*.
Claim 16
Dependent Claim
53 words
An articulated helicopter rotor adapted to mount one or more helicopter blades to extend substantially radially therefrom for motion about a blade feathering axis and intersecting blade lead-lag and blade flapping axes including: A. a rotor hub adapted to be mounted for rotation about an axis of rotation, B. blade attachment means including:
Claim 17
Dependent Claim
53 words
An articulated helicopter rotor adapted to mount one or more helicopter blades to extend substantially radially therefrom for motion about a blade feathering axis and intersecting blade lead-lag and blade flapping axes including: A. a rotor hub adapted to be mounted for rotation about an axis of rotation, B. blade attachment means including:
Claim 18
Dependent Claim
23 words
A rotor according to claim 7 wherein said disc-type bearing is positioned closer to the hub axis of rotation than said spherical bearing.
Claim 19
Dependent Claim
30 words
A rotor according to claim 8 and including a lead-lag damper connected to the radially inner end of said shaft member to dampen lead-lag motion thereof about the lead-lag axis.
Claim 20
Dependent Claim
88 words
A rotor according to claim 7 wherein said spherical elastomeric bearing and said disc-type elastomeric bearing are concentric about the blade feathering axis, wherein the laminates of the spherical elastomeric bearing are alternate layers of elastomer and rigid spherical members bonded to one another and to the bearing inner and outer race, wherein the laminates of said disc-type bearing are alternate elastomer discs and rigid discs bonded to one another and connected to the connecting means and the shaft member at the opposite ends of the disc stack.
Claim 21
Dependent Claim
28 words
A rotor according to claim 10 wherein the laminates of the spherical bearing have inner surfaces which cooperate to form a cone with respect to the shaft member.
Claim 22
Dependent Claim
53 words
A rotor according to claim 7 wherein said blade attachment means supports said shaft member and hence said blade to permit blade pitch change motion through an angle of about 60*, to permit blade lead-lag motion through an angle of about 20*, and to permit blade flapping through an angle of about 30*.
Claim 23
Dependent Claim
60 words
A rotor according to claim 7 wherein said spherical elastomeric bearing is of greater torsional stiffness than said disc-type elastomeric bearing so that said spherical bearing is of minimal height, so that said disc-type elastomeric bearing will accommodate a greater share of the blade pitch change motion, and so that said spherical bearing will accommodate blade lead-lag and flapping motion.
Claim 24
Dependent Claim
43 words
A helicopter rotor according to claim 7 wherein said blade end shaft is shaped to form a reduced diameter stub-shaft at the point of attachment of said damper means so as to minimize the size of said journal bearing and said elastomeric bearing.
Claim 25
Dependent Claim
280 words
In an articulated helicopter rotor wherein the helicopter blades are supported substantially radially from a rotatable hub for rotation therewith about an axis of rotation and for motion with respect thereto about a lead-lag axis, flapping axis and a feathering axis, the improvement of a joint connecting the blade to the hub comprising: A. an annularly shaped, laminated, elastomeric spherical bearing having inner and outer races and stacked laminates of spherical shape centered about the intersection of the lead-lag and flapping axes and positioned substantially concentrically about the feathering axis, B. an annularly shaped, disc-type elastomeric bearing comprising a stack of annular, flat disc laminates positioned substantially concentrically about the feathering axis, C. an annular connecting member concentrically enveloping the feathering axis and connected to the inner race of said spherical bearing and further connected to one end of the stacked discs of said disc-type bearing so as to connect said bearings in series, D. a thru-shaft passing through said spherical bearing connecting member and disc-type bearing and adapted to be connected at one end to the helicopter blade and connected at its opposite end to the opposite end of the disc-type bearing, and E. means connecting said spherical bearing outer race to said hub so that said blade is supported from said hub through said joint so as to be capable of lead-lag and flapping motion which iS accommodated through the torsional motion of said spherical bearing, and so as to also be capable of pitch change motion which is accommodated through the cooperation of said disc-type bearing and said spherical bearing and so that both of said bearings cooperate to impart the blade centrifugal loads to the hub.
Claim 26
Dependent Claim
280 words
In an articulated helicopter rotor wherein the helicopter blades are supported substantially radially from a rotatable hub for rotation therewith about an axis of rotation and for motion with respect thereto about a lead-lag axis, flapping axis and a feathering axis, the improvement of a joint connecting the blade to the hub comprising: A. an annularly shaped, laminated, elastomeric spherical bearing having inner and outer races and stacked laminates of spherical shape centered about the intersection of the lead-lag and flapping axes and positioned substantially concentrically about the feathering axis, B. an annularly shaped, disc-type elastomeric bearing comprising a stack of annular, flat disc laminates positioned substantially concentrically about the feathering axis, C. an annular connecting member concentrically enveloping the feathering axis and connected to the inner race of said spherical bearing and further connected to one end of the stacked discs of said disc-type bearing so as to connect said bearings in series, D. a thru-shaft passing through said spherical bearing connecting member and disc-type bearing and adapted to be connected at one end to the helicopter blade and connected at its opposite end to the opposite end of the disc-type bearing, and E. means connecting said spherical bearing outer race to said hub so that said blade is supported from said hub through said joint so as to be capable of lead-lag and flapping motion which iS accommodated through the torsional motion of said spherical bearing, and so as to also be capable of pitch change motion which is accommodated through the cooperation of said disc-type bearing and said spherical bearing and so that both of said bearings cooperate to impart the blade centrifugal loads to the hub.
Claim 27
Dependent Claim
44 words
A rotor according to claim 15 wherein the improved joint supports said connecting member and hence the blade for pitch change motion through about a 60* angle, for lead-lag motion through about a 20* angle, and for flapping motion through about a 30* angle.
Claim 28
Dependent Claim
60 words
A rotor according to claim 15 wherein said spherical elastomeric bearing is of greater torsional stiffness than said disc-type elastomeric bearing so that said spherical bearing is of minimal height, so that said disc-type elastomeric bearing will accommodate a greater share of the blade pitch change motion, and so that said spherical bearing will accommodate blade lead-lag and flapping motion.
Claim 29
Dependent Claim
244 words
In an articulated helicopter rotor wherein the helicopter blades are supported substantially radially from a rotatable hub for rotation therewith about an axis of rotation and for motion with respect thereto about a lead-lag axis, a flapping axis and a feathering axis, the improvement of a joint connecting the blade to the hub comprising: A. a spherical elastomeric bearing having inner and outer races and elastomer filler therebetween of spherical shape centered about the intersection of the lead-lag and flapping axes, B. a disc-type elastomeric bearing, C. a connecting member connected to the inner race of said spherical bearing and further connected to one end of said disc-type bearing so as to connect said bearings in series, D. a thru-shaft passing through said spherical bearing, connecting member and a disc-type bearing and adapted to be connected at one end to the helicopter blade and connected at its opposite end to the opposite end of the disc-type bearing, and E. means connecting said spherical bearing outer race to said hub so that said blade is supported from said hub through said joint so as to be capable of lead-lag and flapping motion which is accommodated through the torsional motion of said spherical bearing, and so as to also be capable of pitch change motion which is accommodated through the cooperation of said disc-type bearing and said spherical bearing and so that both of said bearings cooperate to impart the blade centrifugal loads to the hub.
Claim 30
Dependent Claim
244 words
In an articulated helicopter rotor wherein the helicopter blades are supported substantially radially from a rotatable hub for rotation therewith about an axis of rotation and for motion with respect thereto about a lead-lag axis, a flapping axis and a feathering axis, the improvement of a joint connecting the blade to the hub comprising: A. a spherical elastomeric bearing having inner and outer races and elastomer filler therebetween of spherical shape centered about the intersection of the lead-lag and flapping axes, B. a disc-type elastomeric bearing, C. a connecting member connected to the inner race of said spherical bearing and further connected to one end of said disc-type bearing so as to connect said bearings in series, D. a thru-shaft passing through said spherical bearing, connecting member and a disc-type bearing and adapted to be connected at one end to the helicopter blade and connected at its opposite end to the opposite end of the disc-type bearing, and E. means connecting said spherical bearing outer race to said hub so that said blade is supported from said hub through said joint so as to be capable of lead-lag and flapping motion which is accommodated through the torsional motion of said spherical bearing, and so as to also be capable of pitch change motion which is accommodated through the cooperation of said disc-type bearing and said spherical bearing and so that both of said bearings cooperate to impart the blade centrifugal loads to the hub.
Claim 31
Dependent Claim
44 words
A rotor according to claim 18 wherein the improved joint supports said connecting member and hence the blade for pitch change motion through about a 60* angle, for lead-lag motion through about a 20* angle, and for flapping motion through about a 30* angle.
Claim 32
Dependent Claim
60 words
A rotor according to claim 18 wherein said spherical elastomeric bearing is of greater torsional stiffness than said disc-type elastomeric bearing so that said spherical bearing is of minimal height, so that said disc-type elastomeric bearing will accommodate a greater share of the blade pitch change motion, and so that said spherical bearing will accommodate blade lead-lag and flapping motion.
References Cited (Backward Citations)
US3106965A
Cited
US3292712A
Cited
US3282350A
Cited
US3501250A
Cited
US3556673A
Cited
US3652185A
Cited
US3700352A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-31 | 1977-07-02 | 1978-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-31 | 1981-07-02 | 1982-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-31 | 1985-07-02 | 1986-01-01 | $7700.00 | Window Closed / Lapsed |