Back to results
US 9,228,571 B2Granted
Variable radial fluid device with differential piston control
AssigneeBell Helicopter Textron Inc.
InventorsCarlos A. Fenny, James E. Sobel
Life of this patent
Estimating the term…
Abstract
According to one embodiment, a radial fluid device comprises a cylinder block, a first plurality of pistons including a first piston, and a second plurality of pistons including a second piston. Each of the first plurality of pistons are slidably received within a different one of a first plurality of radially extending cylinders. Each of the second plurality of pistons are slidably received within a different one of a second plurality of radially extending cylinders. The second piston is configurable to begin its stroke at a different time relative to the first piston within the first cylinder pair.
Claims28
A radial fluid device comprising:
- a cylinder block comprising a first plurality of radially extending cylinders and a second plurality of radially extending cylinders forming a plurality of cylinder pairs, each cylinder pair comprising one cylinder of the first plurality and one cylinder of the second plurality in fluid communication with the one cylinder of the first plurality, the plurality of cylinder pairs comprising a first cylinder pair comprising a first cylinder associated with the first plurality and a second cylinder associated with the second plurality and in fluid communication with the first cylinder;
- a first plurality of cylindrical pistons each slidably received within a different one of the first plurality of radially extending cylinders, the first plurality of cylindrical pistons comprising a first cylindrical piston slidably received within the first cylinder, wherein each cylindrical piston includes:
- a radially extending aperture;
- and
- a shoe configured to slide along a surface of a first cam that has two or more lobes configured such that the shoe completes two or more sinusoidal strokes per revolution of the cylinder block, the shoe having a rounded forward edge and a rounded trailing edge, the forward edge being the forward most edge of the shoe when the shoe experiences movement, the trailing edge being the rearmost edge of the shoe when the shoe experiences movement, wherein the rounded forward and trailing edges form two separate contact surfaces with the first cam and are separated by an elongated portion of the shoe, the first cam being disposed about the first plurality of radially extending cylinders;
- a second plurality of cylindrical pistons each slidably received within a different one of the second plurality of radially extending cylinders, the second plurality of cylindrical pistons comprising a second cylindrical piston slidably received within the second cylinder, wherein the second cylindrical piston is configurable to begin its stroke at a different time relative to first cylindrical piston within the first cylinder pair, wherein each cylindrical piston comprises:
- a radially extending aperture;
- and
- a shoe configured to slide along a surface of a second cam that has two or more lobes configured such that the shoe completes two or more sinusoidal strokes per revolution of the cylinder block, the shoe having a rounded forward edge and a rounded trailing edge, the forward edge being the forward most edge of the shoe when the shoe experiences movement, wherein the rounded forward and trailing edges form two separate contact surfaces with the second cam and are separated by an elongated portion of the shoe, the trailing edge being the rearmost edge of the shoe when the shoe experiences movement, the second cam being disposed about the second plurality of radially extending cylinders;
- and
- a passageway comprising:
- a first opening in fluid communication with the first cylinder of the first cylinder pair;
- a second opening in fluid communication with the second cylinder of the first cylinder pair;
- and
- a third opening alternating between being in fluid communication with a first fluid port and a second fluid port, wherein one of the first and second fluid ports is an inlet and the other of the first and second fluid ports is an exhaust.
12 more elements
A method of adjusting fluid flow in a radial fluid device, comprising:
- providing a cylinder block comprising a first plurality of radially extending cylinders and a second plurality of radially extending cylinders forming a plurality of cylinder pairs, each cylinder pair comprising one cylinder of the first plurality and one cylinder of the second plurality in fluid communication with the one cylinder of the first plurality, the plurality of cylinder pairs comprising a first cylinder pair comprising a first cylinder associated with the first plurality and a second cylinder associated with the second plurality and in fluid communication with the first cylinder;
- providing a first plurality of cylindrical pistons each slidably received within a different one of the first plurality of radially extending cylinders, the first plurality of cylindrical pistons comprising a first cylindrical piston slidably received within the first cylinder, wherein each cylindrical piston includes:
- a radially extending aperture;
- and
- a shoe configured to slide along a surface of a first cam that has two or more lobes configured such that the shoe completes two or more sinusoidal strokes per revolution of the cylinder block, the shoe having a rounded forward edge and a rounded trailing edge, the forward edge being the forward most edge of the shoe when the shoe experiences movement, wherein the rounded forward and trailing edges form two separate contact surfaces with the first cam and are separated by an elongated portion of the shoe, the trailing edge being the rearmost edge of the shoe when the shoe experiences movement, the first cam being disposed about the first plurality of radially extending cylinders;
- providing a second plurality of cylindrical pistons each slidably received within a different one of the second plurality of radially extending cylinders, the second plurality of cylindrical pistons comprising a second cylindrical piston slidably received within the second cylinder, wherein each cylindrical piston includes:
- a radially extending aperture;
- and
- a shoe configured to slide along a surface of a first cam that has two or more lobes configured such that the shoe completes two or more sinusoidal strokes per revolution of the cylinder block, the shoe having a rounded forward edge and a rounded trailing edge, the forward edge being the forward most edge of the shoe when the shoe experiences movement, wherein the rounded forward and trailing edges form two separate contact surfaces with the second cam and are separated by an elongated portion of the shoe, the trailing edge being the rearmost edge of the shoe when the shoe experiences movement, the first cam being disposed about the first plurality of radially extending cylinders;
- providing a passageway, comprising:
- a first opening in fluid communication with the first cylinder of the first cylinder pair;
- a second opening in fluid communication with the second cylinder of the first cylinder pair;
- and
- a third opening alternating between being in fluid communication with a first fluid port and a second fluid port, wherein one of the first and second fluid ports is an inlet and the other of the first and second fluid ports is an exhaust;
- and
- configuring the second cylindrical piston to begin its stroke at a different time relative to the first cylindrical piston within the first cylinder pair.
13 more elements
Dependencies are inferred from the claim text.