Fluid transfer insert
A shaft assembly includes a fluid transfer insert located within a bore of a shaft. The fluid transfer insert seals to the shaft and includes at least one fluid channel that communicates between a plurality of fluid ports located in the shaft. The fluid channel is defined by an outer surface of the fluid transfer insert.
1. A shaft assembly comprising:
a shaft having an inner surface that defines a bore, the bore defining an axis, wherein the shaft has a first fluid port that communicates a fluid to the bore and a second fluid port that communicates the fluid from the bore, wherein the first fluid port is located a distance along the axis from the second fluid port; and
a fluid transfer insert located within the bore and coaxial with the axis, the fluid transfer insert having an outer surface sealingly engaged with the inner surface of the shaft, the outer surface having a first end wall, a second end wall, and a pair of side walls that extend into the fluid transfer insert to define a fluid channel having a length at least greater than the distance between the first fluid port and the second fluid port, the fluid channel parallel to the axis and in communication with the first fluid port and the second fluid port; and
wherein the fluid communicates from the first fluid port through the fluid channel to the second fluid port.
2. The shaft assembly of claim 1 wherein the fluid channel has a bottom surface defined by the outer surface of the fluid transfer insert and a top surface defined by the inner surface of the shaft.
3. The shaft assembly of claim 2 wherein each of the pair of side walls are at a right angle with respect to the bottom surface.
4. The shaft assembly of claim 1 wherein the shaft includes at least eight fluid ports and wherein the fluid transfer insert includes four fluid channels, and wherein each of the fluid channels is in fluid communication with at least two of the plurality of fluid ports such that fluid communicates from four of the eight fluid ports through the four fluid channels to another four of the eight fluid ports.
5. The shaft assembly of claim 4 wherein a first and second of the four fluid channels have a length greater than a length of a third and fourth of the four fluid channels.
6. The shaft assembly of claim 5 wherein the four fluid channels are spaced equally circumferentially apart on the outer surface of the fluid transfer insert.
7. The shaft assembly of claim 1 wherein the fluid transfer insert includes a radial flange that abuts a stepped portion located in the bore of the shaft.
8. The shaft assembly of claim 7 wherein the fluid transfer insert includes a protuberance that engages an aperture located in the bore of the shaft in order to prevent the fluid transfer insert from rotating relative to the shaft.
9. The shaft assembly of claim 1 further comprising a snap ring that engages the inner surface of the bore and is positioned near an end of the fluid transfer insert in order to secure the fluid transfer insert in the bore.
10. The shaft assembly of claim 1 wherein the shaft includes a third fluid port for communicating a fluid to the bore and a fourth fluid port for receiving the fluid from the bore, wherein the fluid transfer insert includes an inner surface that defines a central passage coaxial with the axis of the bore, an opening in an end of the fluid transfer insert that communicates with the central passage, and a fluid port located on the outer surface of the fluid transfer insert that communicates with the central passage, and wherein the fluid communicates from the third fluid port, through the bore, through the opening in the fluid transfer insert, through the central passage, through the fluid port in the fluid transfer insert, and to the fourth fluid port in the shaft.
11. A fluid transfer insert for communicating fluid between a plurality of fluid ports in a shaft assembly, the fluid transfer insert comprising:
a cylindrical outer surface sealingly engaged with the shaft assembly, the outer surface having a plurality of fluid channels each defined by a bottom surface, a pair of end walls that extend into the fluid transfer insert, and a pair of side walls that extend into the fluid transfer insert, wherein each of the fluid channels is in fluid communication with at least a pair of fluid ports in the shaft assembly;
an inner surface that defines a central passage coaxial with the shaft and defines a fluid port that communicates with the central passage and with a fluid port in the shaft assembly;
a first end that defines an opening that communicates with the central passage and at least one of the fluid ports in the shaft assembly;
a second end that includes a radial flange for abutting the shaft assembly; and
a protuberance that extends out from the radial flange for engaging the shaft assembly in order to prevent the fluid transfer insert from rotating relative to the shaft assembly; and
wherein fluid flow communicates from one of the fluid ports in the shaft assembly, through one of the fluid channels and central passage, to another of the fluid ports in the shaft assembly.
12. The fluid transfer insert of claim 11 wherein each of the pair of side walls are at a right angle with respect to the bottom surfaces.
13. The fluid transfer insert of claim 12 wherein the fluid channels are spaced equally circumferentially apart on the outer surface of the fluid transfer insert.
14. The fluid transfer insert of claim 13 wherein a first and second of the fluid channels have a length greater than a length of a third and fourth of the fluid channels.
15. The fluid transfer insert of claim 13 wherein a length of each of the fluid channels is at least equal to a distance between the pair of ports that communicate with each of the fluid channels.