Variable diffuser

Claim 2

An annular diffuser for a radial-flow gas compressor comprising, in combination, front and back walls extending substantially radially from the axis of rotation of the compressor, the walls defining between them a diffusing passage for the gas; a circumferentially spaced set of generally radially and circumferentially extending fixed vanes bridging the passage in a radially outer zone and defining diverging passages between adjacent vanes; and a circumferentially spaced set of generally radially and circumferentially extending movable vanes bridging the passages in a radially inner zone and defining diverging passages between adjacent vanes; each movable vane being mounted so as to be rotatable about an axis generally parallel to the axis of rotation of the compressor; the movable vanes diverging in thickness from the leading edge and each having a trailing edge movable to engage the leading edge of two mutually adjacent fixed vanes so as to close the passage between the fixed vanes so engaged and provide a continuous diffusing passage through the vanes of the two sets to a diffuser exit at the outer end of the fixed vanes; the trailing edges being movable away from the fixed vanes upon rotation of the movable vanes toward the axis of rotation of the compressor to reduce the entrance and discharge areas of the passages between the movable vanes and thus define a diffuser for small flow between the movable vanes, and open the passages between all of the fixed vanes for unimpeded flow of the diffused gas; and common actuating means operable to rotate the movable vanes concurrently.

Claim 3

An annular diffuser for a radial-flow gas compressor comprising, in combination, front and back walls extending substantially radially from the axis of rotation of the compressor, the walls defining between them a diffusing passage for the gas; a circumferentially spaced set of generally radially and circumferentially extending fixed vanes bridging the passage in a radially outer zone and defining diverging passages between adjacent vanes; and a circumferentially spaced set of generally radially and circumferentially extending movable vanes bridging the passage in a radially inner zone and defining diverging passages between adjacent vanes; each movable vane being mounted so as to be rotatable about an axis adjacent to its leading edge generally parallel to the axis of rotation of the compressor; the movable vanes diverging in thickness from the leading edge and each having a trailing edge movable to engage the leading edge of two mutually adjacent fixed vanes so as to close the passage between the fixed vanes so engaged and provide a continuous diffusing passage through the vanes of the two sets to a diffuser exit at the outer end of the fixed vanes; the trailing edges being movable away from the fixed vanes upon rotation of the movable vanes toward the axis of rotation of the compressor to reduce the entrance and discharge areas of the passages between the movable vanes and thus define a diffuser for small flow between the movable vanes, and open the passages between all of the fixed vanes for unimpeded flow of the diffused gas; and common actuating means operable to rotate the movable vanes concurrently.

Claim 4

An annular diffuser for a radial-flow gas compressor comprising, in combination, front and back walls extending substantially radially from the axis of rotation of the compressor, the walls defining between them a diffusing passage for the gas; a circumferentially spaced set of generally radially and circumferentially extending fixed vanes bridging the passage in a radially outer zone and defining diverging passages between adjacent vanes; and a circumferentially spaced set of generally radially and circumferentially extending movable vanes bridging the passage in a radially inner zone and defining diverging passages between adjacent vanes; each movable vane being mounted so as to be rotatable about an axis adjacent to its leading edge generally parallel to the axis of rotation of the compressor; the movable vanes diverging in thickness from the leading edge and each having a trailing edge movable to engage the leading edge of two mutually adjacent fixed vanes so as to close the passage between the fixed vanes so engaged and provide a continuous diffusing passage through the vanes of the two sets to a diffuser exit at the outer end of the fixed vanes; the trailing edges being movable away from the fixed vanes upon rotation of the movable vanes toward the axis of rotation of the compressor to reduce the entrance and discharge areas of the passages between the movable vanes and thus define a diffuser for small flow between the movable vanes, and open the passages between all of the fixed vanes for unimpeded flow of the diffused gas; and common actuating means operable to rotate the movable vanes concurrently.

Claim 5

An annular diffuser for a radial-flow gas compressor comprising, in combination, front and back walls extending substantially radially from the axis of rotation of the compressor, the walls defining between them a diffusing passage for the gas; a circumferentially spaced annular set of generally radially and circumferentially extending movable vanes bridging the passage in a radially inner zone and defining diverging passages between adjacent vanes; each movable vane being mounted so as to be rotatable about an axis adjacent to its leading edge; common actuating means operable to rotate the movable vanes concurrently to vary the entrance and discharge areas of the passages between the movable vanes and thus define a diffuser adjustable for small and large flows between the movable vanes; the movable vanes diverging in thickness from the leading edge and each having a thick trailing edge; and a circumferentially spaced annular set of generally radially and circumferentially extending fixed walls bridging the passage in a zone radially outward of the movable vanes, the walls being in sets of two adjacent walls, one set corresponding to each movable vane, the walls defining an outlet passage between the walls of each set and defining a diverging continuing diffusing passage between each two adjacent sets; the movable vanes in the large flow position each engaging the radially inner ends of the walls of one set to block flow through the outlet passage and to deliver the flow from each diffusing passage through the movable vanes into a continuing diffusing passage between walls sets, and the movable vanes in the small flow position being spaced from the walls to open the outlet passage.

Claim 6

An annular diffuser for a radial-flow gas compressor comprising, in combination, front and back walls extending substantially radially from the axis of rotation of the compressor, the walls defining between them a diffusing passage for the gas; a circumferentially spaced annular set of generally radially and circumferentially extending movable vanes bridging the passage in a radially inner zone and defining diverging passages between adjacent vanes; each movable vane being mounted so as to be rotatable about an axis adjacent to its leading edge; common actuating means operable to rotate the movable vanes concurrently to vary the entrance and discharge areas of the passages between the movable vanes and thus define a diffuser adjustable for small and large flows between the movable vanes; the movable vanes diverging in thickness from the leading edge and each having a thick trailing edge; and a circumferentially spaced annular set of generally radially and circumferentially extending fixed walls bridging the passage in a zone radially outward of the movable vanes, the walls being in sets of two adjacent walls, one set corresponding to each movable vane, the walls defining an outlet passage between the walls of each set and defining a diverging continuing diffusing passage between each two adjacent sets; the movable vanes in the large flow position each engaging the radially inner ends of the walls of one set to block flow through the outlet passage and to deliver the flow from each diffusing passage through the movable vanes into a continuing diffusing passage between walls sets, and the movable vanes in the small flow position being spaced from the walls to open the outlet passage.

Claim 7

An annular diffuser for a radial-flow gas compressor comprising, in combination, front and back walls extending substantially radially from the axis of rotation of the compressor, the walls defining between them a diffusing passage for the gas; a circumferentially spaced annular set of generally radially and circumferentially extending movable vanes bridging the passage in a radially inner zone and defining diverging passages between adjacent vanes; each movable vane being mounted so as to be rotatable about an axis adjacent to its leading edge; common actuating means operable to rotate the movable vanes concurrently including a unison ring rotatable about the axis of rotation of the compressor and pins on the unison ring engaging in slots in the movable vanes remote from the axis of vane rotation to vary the entrance and discharge areas of the passages between the movable vanes and thus define a diffuser adjustable for small and large flows between the movable vanes; the movable vanes diverging in thickness from the leading edge and each having a thick trailing edge; and a circumferentially spaced annular set of generally radially and circumferentially extending fixed walls bridging the passage in a zone radially outward of the movable vanes, the walls being in sets of two adjacent walls, one set corresponding to each movable vane, the walls defining an outlet passage between the walls of each set and defining a diverging continuing diffusing passage between each two adjacent sets; the movable vanes in the large flow position each engaging the radially inner ends of the walls of one set to block flow through the outlet passage and to deliver the flow from each diffusing passage through the movable vanes into a continuing diffusing passage between wall sets, and the movable vanes in the small flow position being spaced from the walls to open the outlet passages.

Claim 8

An annular diffuser for a radial-flow gas compressor comprising, in combination, front and back walls extending substantially radially from the axis of rotation of the compressor, the walls defining between them a diffusing passage for the gas; a circumferentially spaced annular set of generally radially and circumferentially extending movable vanes bridging the passage in a radially inner zone and defining diverging passages between adjacent vanes; each movable vane being mounted so as to be rotatable about an axis adjacent to its leading edge; common actuating means operable to rotate the movable vanes concurrently including a unison ring rotatable about the axis of rotation of the compressor and pins on the unison ring engaging in slots in the movable vanes remote from the axis of vane rotation to vary the entrance and discharge areas of the passages between the movable vanes and thus define a diffuser adjustable for small and large flows between the movable vanes; the movable vanes diverging in thickness from the leading edge and each having a thick trailing edge; and a circumferentially spaced annular set of generally radially and circumferentially extending fixed walls bridging the passage in a zone radially outward of the movable vanes, the walls being in sets of two adjacent walls, one set corresponding to each movable vane, the walls defining an outlet passage between the walls of each set and defining a diverging continuing diffusing passage between each two adjacent sets; the movable vanes in the large flow position each engaging the radially inner ends of the walls of one set to block flow through the outlet passage and to deliver the flow from each diffusing passage through the movable vanes into a continuing diffusing passage between wall sets, and the movable vanes in the small flow position being spaced from the walls to open the outlet passages.