# US 10,501,177 B2 · Convertible propeller > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,501,177 B2 - Document ID: US10501177B2 - Status: Granted - Kind: B2 - Application number: 15/626,825 - Filed: 2017-06-19 - Published: 2018-12-20 - Granted: 2019-12-10 - Earliest claimed: 2017-06-19 - Assignees: General Electric Company - Applicants: General Electric Company - Inventors: Daniel Lawrence Tweedt; Andrew Breeze-Stringfellow - Web page: https://patentgrep.com/patent/US10501177B2 ## CPC - B64C 29/0033: {the propellers being tiltable relative to the fuselage} - B64C 39/08: having multiple wings - B64C 11/003: {Variable-diameter propellers; Mechanisms therefor} - B64C 11/20: Constructional features - B64C 11/28: Collapsible or foldable blades - B64C 11/30: Blade pitch-changing mechanisms - B64C 11/48: Units of two or more coaxial propellers - B64C: AEROPLANES; HELICOPTERS ## Abstract A variable-solidity propeller apparatus, comprising a propeller having at least one rotatable hub carrying at least one row of propeller blades, wherein the propeller has a first configuration in which the propeller has a first average solidity, and a second configuration in which the propeller has a second average solidity which is greater than the first average solidity. ## Claims ### Claim 1 A variable-solidity propeller apparatus, comprising a propeller having at least one rotatable hub carrying at least one row of propeller blades, wherein the propeller has a first configuration in which the propeller has a first average solidity, and a second configuration in which the propeller has a second average solidity which is greater than the first average solidity; and wherein the propeller has a third configuration with an average solidity intermediate between the first and second average solidifies. ### Claim 2 (depends on 1) The apparatus of claim 1 wherein at least a portion of at least some of the propeller blades is movable between a first position defining the first configuration, and a second position defining the second configuration. ### Claim 3 (depends on 1) The apparatus of claim 1 wherein the second average solidity is at least twice as large as the first average solidity. ### Claim 4 (depends on 1) The apparatus of claim 1 further comprising a prime mover coupled in driving relationship with the propeller. ### Claim 5 (depends on 1) The apparatus of claim 1 further comprising a mechanical load coupled to the propeller. ### Claim 6 A variable-solidity propeller apparatus, comprising a propeller including: at least one rotatable hub carrying at least one row of propeller blades, wherein the propeller has a first configuration in which the propeller has a first average solidity, and a second configuration in which the propeller has a second average solidity which is greater than the first average solidity; wherein the propeller includes a first rotatable hub carrying a row of first propeller blades, and a second rotatable hub carrying a row of second propeller blades; the second propeller blades are movable between an extended position and a retracted; and wherein the first propeller blades have a variable pitch angle, and the second propeller blades have a fixed pitch angle. ### Claim 7 (depends on 6) The apparatus of claim 6 further comprising a prime mover coupled in driving relationship with the first and second hubs, wherein the second hub is driven through a clutch configured to be selectively engaged or disengaged from the prime mover. ### Claim 8 (depends on 6) The apparatus of claim 6 further comprising a prime mover coupled in driving relationship with the first and second hubs, wherein the prime mover has spaced-apart forward and aft ends, and both of the first and second hubs are disposed at the forward end, or at the aft end. ### Claim 9 A variable-solidity propeller apparatus, comprising: at least one rotatable hub carrying at least one row of propeller blades, wherein the propeller has a first configuration in which the propeller has a first average solidity, and a second configuration in which the propeller has a second average solidity which is greater than the first average solidity; wherein the propeller includes a first rotatable hub carrying a row of first propeller blades, and a second rotatable hub carrying a row of second propeller blades; and a prime mover coupled in driving relationship with the first and second hubs, wherein the prime mover has spaced-apart forward and aft ends, one of the first and second hubs is disposed at the forward end, and the other of the first and second hubs is disposed at the aft end. ### Claim 10 A variable-solidity propeller apparatus, comprising a propeller having a single hub having a single row of propeller blades, wherein the propeller has a first configuration in which the propeller has a first average solidity, and a second configuration in which the propeller has a second average solidity which is greater than the first average solidity; and wherein some of the propeller blades are fixed and some of the propeller blades are movable between an extended position and a retracted position. ### Claim 11 (depends on 10) The apparatus of claim 10 wherein the row of propeller blades includes an even number of propeller blades, and alternate ones of the propeller blades are movable. ### Claim 12 (depends on 10) The apparatus of claim 10 wherein the propeller blades have a variable pitch angle. ### Claim 13 A variable-solidity propeller apparatus, comprising a propeller having a single hub having a single row of propeller blades, wherein the propeller has a first configuration in which the propeller has a first average solidity, and a second configuration in which the propeller has a second average solidity which is greater than the first average solidity; and wherein at least some of the propeller blades include a retractable section which is movable between an extended position in which the corresponding propeller blade has maximum chord dimensions, and a retracted position in which the corresponding propeller blade has reduced chord dimensions. ### Claim 14 (depends on 13) The apparatus of claim 13 wherein the propeller blades have a variable pitch angle. ### Claim 15 A variable-solidity propeller apparatus, comprising a propeller having a single hub having a single row of propeller blades, wherein the propeller has a first configuration in which the propeller has a first average solidity, and a second configuration in which the propeller has a second average solidity which is greater than the first average solidity, and wherein at least some of the propeller blades include one or more retractable sections which are movable between an extended position in which the corresponding propeller blade has a maximum span dimension, and a retracted position in which the corresponding propeller blade has a reduced span dimension. ### Claim 16 A variable-solidity propeller apparatus, comprising: a first rotor including a first hub mounted for rotation about an axis, the first hub carrying a first row of propeller blades; a second rotor including a second hub mounted for rotation about the axis, the second hub carrying a second row of propeller blades; wherein the second row of propeller blades are movable between an extended position and a retracted position and the first row of propeller blades have a variable pitch angle and the second row of propeller blades have a fixed pitch angle. ### Claim 17 (depends on 16) The apparatus of claim 16 further comprising a prime mover coupled in driving relationship with the first and second hubs, wherein the second hub is driven through a clutch configured to be selectively engaged or disengaged from the prime mover. ### Claim 18 (depends on 16) The apparatus of claim 16 further comprising a prime mover coupled in driving relationship with the first and second hubs, wherein the prime mover has spaced-apart forward and aft ends, and both of the first and second hubs are disposed at the forward end, or at the aft end. ### Claim 19 (depends on 16) The apparatus of claim 16 further comprising a prime mover coupled in driving relationship with the first and second hubs, wherein the prime mover has spaced-apart forward and aft ends, one of the first and second hubs is disposed at the forward end, and the other of the first and second hubs is disposed of the aft end.