High pressure fluid delivery system

An improved high pressure fluid delivery system has a hollow fluid delivery shaft connected at its discharge end to a spray delivery assembly and rotationally driven relative to a hollow housing which internally supports the shaft. The discharge end of a high pressure fluid inlet adapter fitting and the inlet end of the shaft are sealingly interconnected within a seal cartridge removably carried by the housing in a readily accessible location, the inlet fitting and the seal cartridge being clamped to the housing by a cap member threaded onto the housing. High pressure fluid leakage past the seal cartridge into the housing is vented in a manner preventing significant internal fluid pressurization of the housing, thereby permitting it to be formed from a relatively lightweight material such as aluminum. High pressure fluid leakage past the seal cartridge toward the cap member is vented outwardly through a plurality of vent openings formed in the cap member.

BACKGROUND OF THE INVENTION 
The present invention relates generally to high pressure fluid delivery 
systems, and more particularly provides a high pressure spray cleaning 
system having significantly improved sealing and venting means. 
Various high pressure fluid delivery systems have heretofore been utilized 
to convert a flow of high pressure fluid (such as water at 6,000-10,000 
psi or more), via nozzle means, to a high pressure spray used to clean a 
variety of objects. Systems of this general type are exemplified in U.S. 
Pat. Nos. 3,831,845; 3,834,621; 3,977,603; 3,986,523; and 4,128,207. Such 
systems typically comprise a hollow body into which the high pressure 
fluid is forced, and a hollow outlet member communicating with the 
interior of the body and operatively carrying at least one spray nozzle. A 
significant limitation of this type of high pressure fluid system is that 
because the fluid exerts a very high pressure on the interior of the body, 
the body must be of very strong, and therefore relatively heavy 
construction. Particularly in the case of large fluid delivery systems, 
this necessity can significantly increase the overall weight of the 
system. 
Additionally, it is often desirable to provide for driven rotation of the 
nozzle support member relative to the body to clean interior surfaces or 
simply to expand the effective nozzle spray area. In the fluid delivery 
system disclosed in U.S. Pat. No. 3,987,963, this result is achieved by 
connecting the rotationally driven nozzle support member to a hollow fluid 
delivery shaft which is rotatably supported within the hollow body and has 
an inlet end rotatably sealed to the interior surface of the body. High 
pressure fluid is forced into the inlet end of the shaft, through the 
shaft interior, and outwardly through the hollow nozzle support member and 
a spray nozzle carried on the outer end of the support member for rotation 
therewith. 
This construction is intended to isolate the fluid from the interior 
surface of the body which is intended merely to rotatably support the 
shaft portion disposed therein. During normal operation of the system, the 
body is indeed isolated from the high pressure of the supply fluid 
traversing the shaft. However, upon failure of the shaft seal, high 
pressure fluid can leak past the seal, along the shaft inlet portion and 
into the hollow body, thereby at least temporarily exposing the body's 
interior to essentially the full pressure of the supply fluid. 
Additionally, the positioning of the shaft-body seal renders it relatively 
inaccessible, and therefore fairly difficult to periodically inspect and 
replace. 
Accordingly, it is an object of the present invention to provide an 
improved high pressure fluid delivery system of the general type 
described, which eliminates or substantially minimizes above-mentioned and 
other limitations and disadvantages associated with conventional systems. 
SUMMARY OF THE INVENTION 
In carrying out principles of the present invention, in accordance with a 
preferred embodiment thereof, an improved high pressure fluid delivery 
system is provided which incorporates a unique shaft-to-body sealing 
mechanism which is readily accessible and quickly removable, and a body 
venting system which vents high pressure fluid seal leakage in a manner 
preventing the body from being significantly pressurized by the supply 
fluid. 
In a preferred embodiment thereof, the high pressure fluid delivery system 
of the present invention comprises a housing having intercommunicating 
first and second chambers, and a hollow, open-ended fluid delivery shaft 
extending through the first chamber and having an inlet end portion 
projecting into the second chamber, and an outlet end portion. Bearing 
means are positioned within the first chamber and support the shaft for 
rotation relative to the housing, the bearing means defining with the 
interior surface of the first chamber a subchamber interposed between the 
bearing means and the second chamber. A plurality of hollow, elongated 
spray arms are operatively connected to the outlet end portion of the 
fluid delivery shaft for rotation therewith and have connected at their 
outer ends high pressure spray nozzles. Motor and gear means are provided 
for rotating the shaft relative to the housing. 
An inlet member is provided which has an inlet opening for receiving high 
pressure fluid from a source thereof, a discharge portion facing and 
spaced from the shaft inlet end portion and adapted to discharge high 
pressure fluid into and through the shaft, and an internal flow passage 
extending from the inlet opening outwardly through the discharge portion. 
Cartridge seal means are removably positioned in the second chamber and 
sealingly interconnect the inlet member discharge portion and the inlet 
end portion of the shaft. The inlet member and the cartridge seal means 
are captively associated with the housing by a closure cap member which is 
screwed onto the housing and clamps the inlet member and the seal 
cartridge means to the housing. 
To prevent high pressure fluid leaking past the seal cartridge means, along 
the shaft inlet end portion and into the first housing chamber from 
significantly pressurizing the housing interior, the housing subchamber is 
directly vented by means of a vent opening extending outwardly through the 
housing from the interior surface of the housing subchamber. High pressure 
fluid leakage past the cartridge seal means toward the closure cap member 
is vented through a vent opening formed in the cartridge seal means and 
communicating with a plurality of vent openings extending outwardly 
through the closure cap. 
The cartridge seal means are readily accessible for inspection and 
replacement by simply unscrewing the closure cap and lifting the cartridge 
seal means out of the second housing chamber. Because of the direct 
venting of the housing subchamber, the housing is protected from the high 
pressure of the supply fluid and may be formed from a lightweight material 
such as aluminum. In addition to venting high pressure fluid leakage past 
the cartridge seal means, the vent openings give visual indications of 
seal leakage. 
In accordance with another aspect of the present invention, the bearing 
means comprise a spaced pair of annular ball bearing assemblies which 
define therebetween in the housing an annular lubrication subchamber which 
maybe filled with a suitable lubricant by means of a lubrication fitting 
installed on the housing. One of these bearing assemblies partially 
defines the first-mentioned housing subchamber and has an annular sealing 
element extending between its inner and outer races to provide a seal 
between the two housing subchambers. This seal cooperates with the housing 
vent passage to prevent high pressure seal leakage fluid from entering the 
lubrication subchamber.

DETAILED DESCRIPTION 
Illustrated in FIGS. 1 and 2 is an improved high pressure fluid delivery 
system 10 which is utilized to convert a flow of high pressure fluid (for 
example, water having a maximum pressure exceeding approximately 5,000 
psi) to a high pressure spray 12 which may be utilized to clean a variety 
of objects. The basic operating format of system 10 is as follows. Water 
14 from a suitable source 16 thereof is drawn into the inlet 18 of a high 
pressure pump 20 via an inlet pipe 22. Pump 20 discharges a flow of high 
pressure water into the inlet opening 24 of an inlet adapter fitting 26, 
secured to a hollow housing 28, via a discharge pipe 30. The high pressure 
water received by the inlet fitting 26 is forced downwardly through an 
internal flow passage 32 therein into an upper or inlet end portion 34 of 
a hollow, open-ended fluid delivery shaft 36 which is rotatably supported 
within housing 28 and rotationally driven relative thereto by an air motor 
38. A lower or outlet end portion 40 of shaft 36 has fixedly secured 
thereto a hollow fluid discharge hub member 42 which has connected thereto 
four outwardly projecting hollow tubular arm portions 44, each of which 
internally communicates with the open outlet end 40 of shaft 36 via the 
interior of the hub. Threaded into the open outer ends of the arm portions 
44 are four fluid supply tubes 46. Secured to the outer end of each of the 
supply tubes 46 is a hollow nozzle support member 48 which operatively 
carries, in a downwardly and inwardly canted orientation, a high pressure 
spray nozzle 50. During operation of system 10, high pressure water 14 is 
forced downwardly through the rotating shaft 36, and outwardly through the 
nozzles 50 as high pressure spray 12, via the spinning hub 42, supply 
tubes 46 and nozzle support members 48. 
As will be seen, the present invention provides significantly improved 
sealing means between the inlet adapter fitting 26 and the shaft inlet end 
portion 34, such sealing means being readily accessible for rapid removal 
and replacement. It will additionally be seen that the present invention 
uniquely provides means for venting high pressure fluid leakage from seal 
means 60 in a manner which protects the housing 28 from high internal 
fluid pressure, thereby allowing the housing to be formed from a 
relatively lightweight material such as aluminum. 
Housing 28 is of a generally cylindrical configuration, and has a 
vertically extending, annular base wall portion 62 which defines a 
cylindrical first chamber 64 within the housing. Adjacent the upper end of 
the base wall portion 62, the housing exterior wall surface slopes 
upwardly and inwardly to a reduced diameter, exteriorily threaded 
cylindrical upper end portion 66. A central cylindrical bore 68 is formed 
downwardly through the upper end portion 66 of the housing and defines 
therein a second chamber 68 which communicates with the lower chamber 64 
via a central circular opening 70 formed through a housing dividing wall 
72 interposed between the two chambers. 
Shaft 36 extends upwardly through the housing chamber 64 with the shaft 
inlet end portion 34, which is of a substantially smaller diameter than 
the balance of the shaft, extending through the dividing wall opening 70 
and projecting into the upper chamber 68, the opening 70 being of a 
slightly larger diameter than the shaft portion 34. Shaft 36 is supported 
for rotation relative to the housing 28 by means of upper and lower 
annular ball bearing assemblies 74 and 76 disposed within chamber 64 and 
vertically spaced apart by an annular spacer 78 which circumscribes the 
shaft 36. The inner race 74a of bearing 74 abuts the downwardly facing 
surface of an annular shaft flange 79 disposed beneath the dividing wall 
72, while the outer race 74b of bearing 74 abuts the downwardly facing 
surface of an annular interior shoulder portion 80 of the housing. 
As illustrated in FIG. 1, the upper end of bearing 74 defines with the 
interior surface of housing chamber 64 a generally annular subchamber 64a 
interposed between the dividing wall 72 and the bearing 74. The bearings 
74, 76 define therebetween in the chamber 64 an annular lubrication 
subchamber 64b which may be filled with a suitable lubricant via a 
lubrication fitting 82 threaded into an opening 84 formed through the 
housing wall 62 between the upper and lower bearings. An annular sealing 
member 86 extending between the inner and outer races 74a, 74b of bearing 
74 above its ball bearings 74c provides a seal between the subchambers 64a 
and 64b to prevent transfer of water or lubricant across the upper bearing 
74. 
The upper bearing 74 is a radial bearing, but the lower bearing 76 is a 
thrust bearing of the "angular-contact" type designed to accept both 
radial and axial thrust loads. Accordingly, lower bearing 76 accepts the 
axial thrust load imposed on the shaft 36 by the high pressure fluid force 
on its upper end. The unique use of an angular-contact type bearing in 
conjunction with the pure radial bearing as illustrated provides a 
particularly compact radial-and-thrust bearing structure within the 
housing 28. 
As illustrated in FIG. 1, a lower end portion of the shaft 36 extends 
downwardly through the upper and lower walls 90, 92 of a hollow gear 
housing 94, such lower end portion of the shaft projecting downwardly from 
the lower housing wall 92 and being threaded into a vertically extending 
hollow central cylindrical inlet portion 96 of the discharge hub 42. The 
lower end of the housing 28 is secured to the upper gear housing wall 90 
by bolts 98. Shaft 36 is rotationally sealed to upper housing wall 90 by a 
suitable annular seal 100, while the cylindrical hub member portion 96 is 
rotatably sealed to the lower housing wall 92 by an annular seal 102. The 
upper hub portion 96 is further secured to the outlet end portion of shaft 
36 by a small set screw 104 extending through hub portion 96 into an 
annular groove 106 formed in the periphery of lower shaft end portion 40. 
Air motor 38 is suitably secured to the upper gear housing wall 90 and has 
an output shaft 110 which extends into the interior of the gear housing 
and is rotationally locked to a small driving gear 112 therein by means of 
a set screw 114 extending through gear 112 into a longitudinally extending 
slot 116 formed on the shaft 110. Gear 112 meshes with a larger diameter 
driven gear 118 disposed within the gear housing and rotationally locked 
to the fluid delivery shaft 36 by means of a small key member 120. 
Rotation of the motor shaft 110 causes rotation of the fluid delivery 
shaft 36 relative to the housings 28, 94 and concomitant rotation (as 
indicated by the arrows 120 in FIG. 2) of the spray delivery assembly 
defined by the hub 42, the supply tubes 46, the nozzle support members 48 
and the spray nozzles 50. If desired, the annular shaft seal 100 could be 
deleted, and a suitable passage extending between subchamber 64b and the 
interior of gear housing 94 substituted therefor, so that lubricant forced 
into subchamber 64b via the fitting 82 would also be forced into the gear 
housing to lubricate the gears therein. 
The inlet adapter fitting 26 has a generally cylindrical configuration and 
has, adjacent its lower end, an annular external flange 122. Projecting 
downwardly from flange 122 is a reduced diameter cylindrical hub 124 
having a still smaller diameter cylindrical outlet portion 126 projecting 
downwardly therefrom. The downwardly extending inlet member passage 32 
opens outwardly through the lower end of discharge portion 126 which 
projects downwardly into the upper housing chamber 68 and is positioned in 
a spaced, facing relationship with the open upper end of the inlet end 
portion 34 of the hollow shaft 36, discharge portion 126 having an outer 
diameter equal to the outer diameter of the upper shaft end portion 34. It 
can be seen that discharge portion 126 is positioned to force high 
pressure water discharged therefrom into the inlet end portion 34 of the 
fluid delivery shaft 36. 
The sealing means 60 include a hollow, cylindrical seal cartridge 130 which 
is removably received in the upper housing chamber 68, the cartridge 
having a lower end wall 132 which abuts the upper surface of the dividing 
wall 72, and a hollow cylindrical body portion 134 which projects upwardly 
from the wall 132. Cartridge body 134 has, at its upper end, an annular 
external flange 136 which is spaced upwardly from the upper end of the 
threaded upper end portion 66 and abuts the inlet adapter flange 122. The 
inlet end portion 34 of shaft 36 is rotatably received in a circular bore 
138 formed through the bottom cartridge wall 132 and, like the discharge 
portion 126 of the inlet adapter 26, projects into the interior of the 
seal cartridge 130 with a lower end portion of adapter hub being received 
in an upper end portion of the cartridge interior. 
Positioned within the interior of seal cartridge 130 are an upper annular 
seal member 140, which forms an annular seal between the discharge portion 
126 and the interior of the seal cartridge 130, and a lower annular seal 
member 142 which forms an annular seal between the inlet end portion 34 of 
shaft 36 and the interior surface of the seal cartridge. Seals 140, 142 
are vertically spaced apart by a suitable annular seal spacer member 144 
disposed within the seal cartridge interior and circumscribing the facing 
portions of elements 34 and 126. 
The inlet adapter member 26 and the seal cartridge 130 are clamped to the 
housing 28 by means of a generally annular retaining or closure cap 146 
having an upper end wall 148 and an interiorly threaded annular wall 
depending therefrom which is screwed onto the threaded upper end portion 
66 of the housing 28. End wall 148 has a large, central circular opening 
152 formed therethrough which outwardly circumscribes a portion of the 
inlet fitting immediately above the inlet fitting flange 122. The inlet 
fitting flange 122 and the seal cartridge 130 are disposed within the cap 
146, the cap endwall 148 bearing against the inlet fitting flange 122 
which in turn bears against the seal cartridge upper flange 136. 
The seal means 60, which interconnect the discharge portion 126 and the 
shaft inlet end 34 with a sealed fluid passageway 154, are easily 
accessible for inspection, removal and replacement of the seals 140, 142 
by simply unscrewing the retainer cap 146 and lifting the seal cartridge 
130 out of the housing chamber 68. During normal operation of the system 
10, the seal means 60 function to completely isolate the housing 28 from 
the high pressure of the water 14 downwardly traversing the rotating fluid 
delivery shaft 36. This allows the housing 28 to function merely as a 
support member for the bearings 74 and 76, and other system components 
carried by the housing, thus allowing the housing 28 to be formed from a 
relatively light-weight material such as aluminum. 
However, it can be seen that in the event of failure of the lower cartridge 
seal 142, high pressure water can be forced downwardly between the seal 
142 and the upper shaft portion 34 into the interior of the housing 28, 
thereby potentially subjecting the housing to and internal fluid pressure 
of at least 5,000 psi. This potential high internal pressurization of the 
housing 28 is uniquely avoided in the present invention by the provision 
of a vent opening 160 which extends laterally outwardly through the 
housing wall 62 from the interior surface of the subchamber 64a. The vent 
opening 160 functions to directly vent subchamber 64a to limit potential 
fluid pressure therein, and to further prevent high pressure fluid 
entering such subchamber from being forced downwardly across the inner and 
outer annular peripheries of bearing 74 into the lubrication subchamber 
64b. 
Extending radially inwardly through the periphery of the shaft flange 79 is 
a circular bore 160a which is vertically aligned with the laterally 
extending vent passage 160. Bore 160afacilitates removal the hub 42 from 
the shaft 36, or its attachment thereto, in the following manner. With 
bore 160a facing the vent passage 160 a suitable rod or other locking 
member (not shown) may be inserted inwardly through vent passage 160 and 
into the bore 160a to thereby rotationally lock the shaft 36 relative to 
the housing 28. With the shaft rotationally locked in this manner, the hub 
42 may be easily screwed onto the lower end of shaft 36 or unscrewed 
therefrom. 
Additional means are provided for venting the seal cartridge 130 in the 
event that the upper cartridge seal 140 begins to leak. Specifically, 
upward fluid leakage across seal 140, between such seal and the interior 
surface of the seal cartridge 130, is forced upwardly into a small annular 
chamber 162 positioned between the cartridge flange 136 and the inlet 
fitting hub 124, and then outwardly through a vent opening 164 formed 
through the cartridge flange 136. High pressure fluid leakage exiting the 
vent passage 164 enters a small annular chamber 166 defined between the 
cartridge 130 and the cap wall 150 directly above the upper housing end 
portion 66, and is discharged through a plurality of vent openings 168 
formed through the annular cap body 150. In addition to performing the 
previously described leakage venting functions, the vent openings 160 and 
168 also provide an easy visual indication of failure of a seal portion of 
the seal means 60. 
It can be seen from the foregoing that the present invention provides a 
significantly improved, and more readily accessible, seal mechanism 
between the stationary inlet member 26 and the rotating shaft 36. 
Additionally, the seal means 60 effectively isolate the housing 28 from 
the very high pressure of the water 14. Moreover, by virtue of the housing 
vent opening 160, the housing is protected from such high fluid pressure 
even during periods of seal failure. 
The foregoing detailed description is to be clearly understood as given by 
way of illustration and example only, the spirit and scope of this 
invention being limited solely by the appended claims.