Patent US3895883A successfully refreshed from Google Patents.
US3895883A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Propeller pitch indicator
Assignee: Individual
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Filing: 1973-10-29
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Granted: 1975-07-22
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Expires: 1993-10-29
Abstract
Abstract Indicator for a marine controllable pitch propeller mounted on solid or hollow tailshaft. Indicator is free of inaccuracies arising from tailshaft compression and lost motion between linkages. Components of indicator that are susceptible to wear are generally accessible for servicing without dry-docking vessel. Indicator has sensor connecting electrical position transducer to a component within the propeller hub, which component moves in response to pitch change. The transducer can be mounted within the hub, or on the tailshaft externally of the hub, electrical output from transducer being transmitted from tailshaft through a rotary contact unit using conducting rings engaged by brushes. Galvanometer calibrated in pitch reflects current from transducer which is dependent on pitch of propeller. Sleeve conduit provides clearance for output from sensor through bearing sleeve without boring tailshaft.
Inventors
- 👤 James Miller Pedersen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:06
CPC Classifications
B; B63; B63H; B63H3/00
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
414 words
A propeller pitch indicator for indicating pitch of a controllable pitch propeller of a marine vessel at a station remote from the propeller, the propeller having a hub, a hub datum, and a pitch reflecting means of the hub movable relative to the hub datum to reflect pitch of the propeller, the propeller being mounted on a tailshaft journalled for rotation relative to the vessel, the indicator including: a. a sensor cooperating with the hub to rotate therewith, the sensor including a precision sheathed control link having a longitudinal axis disposed generally parallel to the tailshaft and being capable of transmitting force in both directions along the axis, the link having a sheath and a control rod, the sheath enclosing the control rod and having an outer end secured relative to the hub and the shaft, and an inner end supported radially relative to the tailshaft to rotate therewith, portions of the sheath remote from the outer end thereof being permitted to move axially relative to the tailshaft; the control rod having an outer end cooperating with a stylus engaging the pitch reflecting means, and an inner end responsive to movement of the stylus, b. a position transducer cooperating with the inner end of the sensor and adapted to rotate therewith, the transducer having a resistance member coupled to an electrical power source so as to conduct electrical current to produce an electrical potential drop across the resistance member, and a movable contact member adapted to sweep the resistance member so as to provide a variable potential at the contact member proportional to position of the contact member relative to the resistance member, the contact member cooperating with the sensor so as to be responsive to position of the stylus relative to the hub datum so that the contact member is at an electrical potential dependent on position of the stylus, so that output from the transducer reflects position of the pitch reflecting means, c. a galvanometer adapted to be fitted in the vessel remote from the hub so as to be stationary relative to the vessel, the galvanometer being connected to output from the contact member and the electrical power source and being responsive to current from the contact member, which current is dependent upon pitch of the propeller, the galvanometer being adapted to indicate pitch of the propeller, d. a rotary contact unit cooperating with the shaft, the unit connecting electrically the galvanometer and the electrical power source to the position transducer.
Claim 2
Dependent Claim
414 words
A propeller pitch indicator for indicating pitch of a controllable pitch propeller of a marine vessel at a station remote from the propeller, the propeller having a hub, a hub datum, and a pitch reflecting means of the hub movable relative to the hub datum to reflect pitch of the propeller, the propeller being mounted on a tailshaft journalled for rotation relative to the vessel, the indicator including: a. a sensor cooperating with the hub to rotate therewith, the sensor including a precision sheathed control link having a longitudinal axis disposed generally parallel to the tailshaft and being capable of transmitting force in both directions along the axis, the link having a sheath and a control rod, the sheath enclosing the control rod and having an outer end secured relative to the hub and the shaft, and an inner end supported radially relative to the tailshaft to rotate therewith, portions of the sheath remote from the outer end thereof being permitted to move axially relative to the tailshaft; the control rod having an outer end cooperating with a stylus engaging the pitch reflecting means, and an inner end responsive to movement of the stylus, b. a position transducer cooperating with the inner end of the sensor and adapted to rotate therewith, the transducer having a resistance member coupled to an electrical power source so as to conduct electrical current to produce an electrical potential drop across the resistance member, and a movable contact member adapted to sweep the resistance member so as to provide a variable potential at the contact member proportional to position of the contact member relative to the resistance member, the contact member cooperating with the sensor so as to be responsive to position of the stylus relative to the hub datum so that the contact member is at an electrical potential dependent on position of the stylus, so that output from the transducer reflects position of the pitch reflecting means, c. a galvanometer adapted to be fitted in the vessel remote from the hub so as to be stationary relative to the vessel, the galvanometer being connected to output from the contact member and the electrical power source and being responsive to current from the contact member, which current is dependent upon pitch of the propeller, the galvanometer being adapted to indicate pitch of the propeller, d. a rotary contact unit cooperating with the shaft, the unit connecting electrically the galvanometer and the electrical power source to the position transducer.
Claim 3
Dependent Claim
30 words
A propeller pitch indicator as claimed in claim 1 in which the stylus is spring-urged against the pitch reflecting means so as to follow movements of the pitch reflecting means.
Claim 4
Dependent Claim
46 words
A propeller pitch indicator as claimed in claim 1 in which i. the transducer is secured to the inner end of the sheath so as to move axially therewith relative to the tailshaft to accommodate tailshaft compression, ii. the contact member cooperates with the control rod.
Claim 5
Dependent Claim
89 words
A propeller pitch indicator as claimed in claim 1 in which i. the control is a relatively stiff cylindrical pushrod having a diameter, ii. the sheath is a relatively stiff cylindrical tube enclosing the pushrod and having a bore sufficient to accept the pushrod and permit free sliding therebetween, the tube having an inner end supported radially relative to the tailshaft to rotate therewith and permitted to move axially relative to the shaft to accommodate the tailshaft compression, the rod and sheath having sufficient flexibility to follow gentle bends.
Claim 6
Dependent Claim
325 words
A propeller pitch indicator as claimed in claim 1 in which the control link is a linear ball bearing which includes: i. a central flexible strip serving as the control rod and having parallel side edges and first and second opposed surfaces, each surface having a continuous axial groove extending therealong serving as first and second inner ball races, ii. a first row of spaced balls provided adjacent the first surface of the central strip, the balls engaging the axial groove of the first surface; a second row of spaced balls being provided adjacent the second surface and similarly engaging the axial groove of the second surface, iii. a first longitudinal ball guide having openings to accept the balls, the ball guide being spaced from the first surface of the central strip and engaging the balls so as to maintain separation between the balls; a similar second longitudinal ball guide engaging the second row of balls on a side of the strip remote from the first ball guide, iv. a first outer longitudinal ball race spaced from the first surface of the central strip, the outer ball race having a longitudinal groove extending therealong, the groove accepting the first row of balls, the first longitudinal ball guide being positioned between the first outer ball race and the central flexible strip; a similar second outer longitudinal ball race being provided spaced from the second surface of the central strip and engaging the second row of balls, v. a flexible cylindrical sheath enclosing the central strip, the two rows of balls, the two ball guides and the two outer longitudinal ball races, the outer ball races being secured to the sheath at diametrically opposite positions so as to prevent relative movement therebetween, clearance between the inner and outer races and the central strip being such that the central strip is free to slide axially relative to the sheath, the balls supporting the central strip against excessive deviation.
Claim 7
Dependent Claim
153 words
A propeller pitch indicator as claimed in claim 5 in which: i. the transducer is a linear position transducer having a rod extending axially of the transducer, and the contact member of the transducer being coupled to the rod, ii. the outer end of the sensor is a plunger having an outer end serving as the stylus being in engagement with the pitch reflecting means of the hub, a body secured to the hub slidably mounting the plunger so as to permit axial sliding of the plunger, the plunger having an inner end, iii. the outer end of the link includes an outer end of the central flexible strip coupled to the inner end of the plunger, the sheath being restricted against axial movement relative to the hub, iv. the inner end of the link has an inner end of the central flexible strip coupled to the rod extending axially from the transducer.
Claim 8
Dependent Claim
129 words
A propeller pitch indicator as claimed in claim 1 in which the rotary contact unit includes: i. a rotor secured to the shaft, the rotor having three conducting rings disposed concentrically relative to the shaft, first and second rings being connected to the resistance member to conduct electrical current to and from the resistance member, a third ring being connected to the contact member to conduct current from the contact member, ii. a pick-up means fixed relative to the vessel, the pick-up means having three brushes, each brush contacting a respective ring, first and second brushes contacting the first and second rings to conduct electrical current to and from the resistance member, the third brush contacting the third ring to conduct current from the contact member to the galvanometer.
Claim 9
Dependent Claim
96 words
A propeller pitch indicator as claimed in claim 1 in which the tailshaft has a sleeve conduit characterized by: i. a sleeve secured to the tailshaft, the sleeve having an axial lengtH, an outer surface concentric with the tailshaft and adapted to run within a shaft enclosure fixed relative to the vessel, and an inner surface having a groove extending the length of the sleeve and defining a passage between the sleeve and the tailshaft, the passage providing clearance through the sleeve and the shaft enclosure for a means transmitting pitch signal output of the stylus.
Claim 10
Dependent Claim
130 words
A propeller pitch indicator as claimed in claim 1 in which the tailshaft has a sleeve conduit characterized by: i. a sleeve assembly secured to the tailshaft, the sleeve assembly having an inner sleeve having an axial length and secured to the tailshaft, and an outer sleeve enclosing and secured to the inner sleeve, the outer sleeve having an outer surface concentric with the shaft and adapted to run within a shaft enclosure fixed relative to the vessel, the inner sleeve having an outer surface having a groove extending the length of the inner sleeve so as to define a passage between the inner sleeve and the outer sleeve, the passage providing clearance through the sleeve and the shaft enclosure for a means transmitting pitch signal output of the stylus.
Claim 11
Dependent Claim
110 words
A propeller pitch indicator as claimed in claim 1 in which the tailshaft has a sleeve conduit characterized by: i. the tailshaft having an outer surface having a groove extending therealong, ii. a sleeve having inner and outer surfaces, the inner surface having a length shorter than the length of the groove and being adapted to be secured to the outer surface of the tailshaft, the outer surface of the groove being concentric with the tailshaft and adapted to run within a shaft enclosure between the sleeve and the tailshaft to provide clearance through the sleeve and the shaft enclosure for a means transmitting pitch signal output of the stylus.
References Cited (Backward Citations)
US2307040A
Cited
US2355039A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-21 | 1979-01-20 | 1979-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-21 | 1983-01-20 | 1983-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-21 | 1987-01-20 | 1987-07-22 | $7700.00 | Window Closed / Lapsed |