Self regulating fluid bearing high pressure rotary retarder nozzle
A rotary nozzle having a rotating shaft operating within a cylindrical housing is balanced by allowing passage of a small amount of pressurized fluid to be bled to an area between the outside of the opposite end of the shaft and the inside of the housing where the fluid force acts axially in an opposing direction upon the shaft to balance the axial inlet force exerted by the pressurized fluid. The balance of axial forces is self-regulating by controlling escape of the fluid through a tapered or frusto-conical region between the shaft and housing. A plurality of centrifugal weight segments around the inlet end of the shaft are thrust outwardly against the cylindrical housing to retard rotational speed while pressurized fluid around the centrifugal weight segments provides a fluid bearing between the weights and the housing.
1 . A nozzle assembly for spraying pressurized fluid against an object, the nozzle assembly comprising:
a cylindrical housing body;
a tubular shaft member coaxially and rotatably carried within the cylindrical housing body and having an inlet end within and near one end of the cylindrical housing body, the tubular shaft member having an outlet end near a second end of the cylindrical housing body for securing a spray head thereto for rotation with the tubular shaft member, the tubular shaft member having a central passage to conduct fluid from the inlet end of the tubular shaft member to the outlet end of the tubular shaft member;
a regulating passage formed between the cylindrical housing body and an outer surface of the tubular shaft member;
one or more bores communicating between the central passage of the tubular shaft member and the regulating passage, wherein pressure of the fluid within the regulating passage acts axially upon the tubular shaft member to counterbalance axial force on the tubular shaft member exerted by fluid pressure acting upon the inlet end of the tubular shaft member;
a plurality of partial annular segments disposed on the tubular shaft member in the cylindrical housing body and captured on a rail extending laterally across the central passage between the inlet end of the tubular shaft member and the cylindrical housing body, wherein the plurality of annular segments are rotationally fixed to a raised rib extending outwardly from the rail to constrain the plurality of partial annular segments to rotate with the tubular shaft member, and wherein the plurality of partial annular segments are separable in an outward direction from the tubular shaft member and press against the cylindrical housing body thereby reducing rotational speed of the tubular shaft member within the cylindrical housing body during nozzle operation; and
wherein each segment of the plurality of partial annular segments engages the rib to preclude axial movement of the plurality of partial annular segments.
2 . The nozzle assembly according to claim 1 wherein the regulating passage is a tapered frusto-conical gap defined between the tubular shaft member and the cylindrical housing body.
3 . The nozzle assembly according to claim 1 wherein each segment of the plurality of partial annular segments is a half annular segment disposed on the tubular shaft member between the regulating passage and an inlet bearing area of the cylindrical housing body.
4 . The nozzle assembly according to claim 3 wherein the rail is formed on the tubular shaft member between the inlet end of the tubular shaft member and a tapered surface portion of the tubular shaft member.
5 . The nozzle assembly according to claim 1 wherein the rail is formed between the inlet end of the tubular shaft member and a tapered surface portion of the tubular shaft member.
6 . The nozzle assembly according to claim 1 wherein each segment of the plurality of partial annular segments has a partial internal recess facing the tubular shaft member.
7 . The nozzle assembly according to claim 1 wherein the rail has a constant cross sectional shape and carries the plurality of partial annular segments.
8 . The nozzle assembly according to claim 7 wherein each segment of the plurality of partial annular segments has a shape complementary to a cross sectional shape of the rail.
9 . The nozzle assembly according to claim 7 wherein each segment of the plurality of partial annular segments has a groove complementary to the rib to constrain movement of the plurality of partial annular segments in a radial direction toward or away from the central passage through the tubular shaft member.
10 . The nozzle assembly according to claim 9 wherein each segment of the plurality of partial annular segments has a partial axially flat outer surface.
11 . The nozzle assembly of claim 1 , wherein the plurality of partial annular segments is configured to travel radially outward upon rotation of the tubular nozzle shaft.
12 . A nozzle assembly for spraying pressurized fluid against an object, the nozzle assembly comprising:
a housing body;
a tubular shaft member coaxially and rotatably carried within the housing body and having an inlet end and an outlet end, the tubular shaft member having a central passage to conduct fluid from the inlet end to the outlet end;
a regulating passage formed between the housing body and an outer surface of the tubular shaft member, wherein fluid pressure within the regulating passage counterbalances a force exerted by fluid moving through the central passage of the tubular shaft member;
a plurality of partial annular segments;
a rail having a raised rib that extends outward from the rail, wherein the rail extends laterally across the central passage;
wherein the plurality of annular segments are rotationally fixed to the raised rib to constrain the plurality of partial annular segments to rotate with the tubular shaft member, and wherein the plurality of partial annular segments are separable along the rail in an outward direction in response to a centrifugal force generated by rotation of the tubular shaft member, wherein the plurality of partial annular segments press against the housing body thereby reducing rotational speed of the tubular shaft member within the housing body during nozzle operation; and
wherein each segment of the plurality of partial annular segments engages the rib to preclude axial movement of the plurality of partial annular segments.
13 . The nozzle assembly according to claim 12 wherein each segment of the plurality of partial annular segments is a half annular segment disposed on the tubular shaft member between the regulating passage and an inlet bearing area of the housing body.
14 . The nozzle assembly according to claim 12 wherein the rail is formed between the inlet end of the tubular shaft member and a tapered surface portion of the tubular shaft member.
15 . The nozzle assembly according to claim 12 wherein the rail has a constant cross sectional shape and carries the plurality of partial annular segments.
16 . The nozzle assembly according to claim 15 wherein each segment of the plurality of partial annular segments has a shape complementary to a cross sectional shape of the rail.
17 . The nozzle assembly according to claim 15 wherein each segment of the plurality of partial annular segments has a groove complementary to the rib to constrain movement of the plurality of partial annular segments in a radial direction toward or away from the central passage through the tubular shaft member.
18 . The nozzle assembly of claim 12 , wherein the plurality of partial annular segments is configured to travel radially outward upon rotation of the tubular nozzle shaft.