A snow-making machine is disclosed which includes a first group of air-water snow-making nozzles and a second group of airless, water atomizing nozzles. A distributional air fan is driven by a water turbine. Water for the air-water snow-making nozzles is derived from the outlet side of the turbine, while water for the airless nozzles is derived from the intake side of the turbine. A novel construction of air-water manifold ring and air-water nozzles associated therewith is also described. The construction provides a high efficiency, low cost, lightweight snow-making unit, ideally suited for ski area snow-making operations.

RELATED APPLICATION 
This application is closely related to and constitutes an improvement over 
the subject matter of my copending U.S. application Ser. No. 705,042, 
filed Feb. 25, 1985, which is a continuation of Ser. No. 630,346, filed 
July 13, 1984, now abandoned, which is a continuation of Ser. No. 360,610, 
filed Mar. 22, 1982, now abandoned. 
BACKGROUND AND SUMMARY OF THE INVENTION 
In my above mentioned copending application, an improved snow-making system 
is described, in which the snow-making procedure at a mountain ski area is 
made substantially more efficient and economical by incorporating into the 
snow-making apparatus a turbine-driven fan, which provides a relatively 
high velocity stream of distributional air into which the atomized 
water/air mixtures are discharged. The system makes use of the mountain 
site supplies of pressurized water and air. However, by utilizing the 
energy available in the pressurized water system to drive a fan for 
distribution air, important economies can be realized in the snow-making 
operation itself, and the capital requirements of the installation may be 
kept at a minimum, as compared to systems of similar snow-making 
capability. 
The apparatus of the present invention makes use of the basic principles of 
my copending application, in providing for driving of the distribution air 
fan by means of a turbine motor operating from the pressurized water 
source prior to its discharge through snow-making nozzles. The apparatus 
of the present invention, however, further incorporates a number of novel 
and highly advantageous structural enhancements which add significantly to 
the snow-making efficiency of the unit and also provide for a great deal 
of flexibility in the operation of the unit, depending upon ambient 
conditions. 
In accordance with one of the more specific features of the invention, a 
snow-making apparatus is provided with a novel and advantageous 
arrangement and orientation of snow-making and nucleating nozzles 
providing enhanced cooperation and efficiencies in the combined 
snow-making capabilities of the several nozzles. In this respect, a series 
of snow-making and nucleating nozzles are arranged about a generally 
circular manifold structure. The snow-making nozzles are of a type to 
discharge a somewhat flat (as distinguished from purely circular) spray 
discharge pattern and these spray patterns are oriented and aimed in an 
advantageous way to achieve superior snow-making efficiency. 
In accordance with another feature of the invention, a unique water-air 
manifold structure is provided which accommodates direct mounting of the 
nozzles and which provides advantageously for the bathing of the nozzles, 
particularly in the area of the air-water intermixing zone, in the water 
mass of the water manifold. This arrangement significantly reduces the 
opportunity for nozzle freezeups, which can be a problem with snow-making 
equipment, particularly at shutdown, when residual water in the system, 
which is no longer in motion, can quickly freeze up in and around the 
various nozzle passages and openings. 
In accordance with a further aspect of the invention, provision is made in 
a snow-making apparatus having a water turbine-driven distribution fan, 
for diversion of some of the water from the inlet side of the turbine to a 
series of selectively operable water atomizing nozzles arrayed around and 
generally above the main stream of distribution air and air-water 
discharge from the various primary snow-making nozzles. The arrangement is 
such that, when ambient conditions permit (i.e., when temperatures are 
sufficiently below freezing) some or all of the auxiliary nozzles may be 
opened to discharge water alone, at high pressures through water atomizing 
nozzles. This discharge is directed generally into the main stream of 
distribution air and atomized air-water mixtures and provides for 
increased delivery of snow, as conditions permit. 
For a better understanding of the above and other features and advantages 
of the invention, reference should be made to the following detailed 
description of a preferred embodiment of the invention, and also to the 
accompanying drawings.

DESCRIPTION OF A PREFERRED EMBODIMENT 
Referring now to the drawing, and initially to FIG. 1 thereof, a typical 
snow-making apparatus according to the invention may include a sled 10 and 
tow bar 11 to provide mobility around the mountain site. Mounted on the 
sled 10 is a swivel base 12 on which is mounted a yoke 13 arranged for 
unlimited swiveling movement about a vertical axis. Water and air inlets, 
of which air inlet 14 is illustrated, are provided in the base 12, which 
is fixed to the sled. A rotary element 15, which is mounted on the base 12 
and carries the yoke elements 13 is also provided with air and water 
outlet conduits 16, 17 which lead to the snow-making equipment. 
The snow-making unit, generally designated by the reference numeral 18, is 
mounted by the yoke members 13 for tilting movement about a horizontal 
axis, being secured in an adjusted position by means of a locking handle 
19. 
The snow-making unit includes a main shroud 20 which mounts and encloses a 
fan F (FIG. 2) driven by a water turbine 21. At the rear, the housing has 
an outwardly flared skirt 22 forming an air intake. When the system is in 
operation, a relatively high velocity distributional airflow is provided 
by the tubine driven fan and is directed forwardly, through the annular 
discharge opening 23 at the forward end of the main shroud 20. In the 
particular embodiment shown, the shroud 20 also encloses a central housing 
24 for a tachometer generator or similar device for measuring the speed of 
the fan when the system is in operation. 
Mounted concentrically around the forward portion of the main shroud 20 is 
an annular air/water manifold ring 25 having annular manifold chambers 26, 
27 for air and water respectively (see FIG. 4). In accordance with one 
aspect of the invention, the manifold 25 is constructed of a pair of 
annular castings 28, 29 of open sided, U-shaped cross section. These are 
arranged, as shown in FIG. 4, to form facing front and rear housings. An 
annular separating ring 30 is positioned between the respective front and 
rear manifold housings, and resilient sealing rings 31, 32 are provided at 
the interfaces between the separating ring and the respective housings, to 
form fluid tight seals. Thus, when the front and back manifold housings 
28, 29 are clamped securely to the separating ring 30, the annular 
manifold chambers 26, 27, for air and water respectively are formed. Water 
and air inlet connections are provided to the manifold at 34, 35 (see FIG. 
2). These respective inlet connections are oriented at the bottom of the 
manifold to accommodate drainage at shut down. 
Assembly of the manifold 25, and mounting of the various nozzles thereon, 
involves certain unique and advantageous features to be described in more 
detail. The various nozzle assemblies, whether nucleating nozzles or 
regular snow-making nozzles, are generally in the form illustrated in 
FIGS. 5-10. Each nozzle includes an air tube 40 arranged to be received in 
a bore 41 in the manifold separating ring 30. The bores 41 advantageously 
are arranged at a slight angle to the central axis of the manifold ring, 
such that the nozzles converge toward the central axis at an angle of 
approximately five degrees thereto. The arrangement is such that the axes 
of all of the bores 41 nominally converge with the central longitudinal 
axis at a common point spaced well in front of the snow-making equipment. 
As will be later described, however, the nozzles themselves are oriented 
somewhat differently, to avoid convergence at a common point. 
As illustrated in FIG. 5, the central section 42 of the air tube 40 is of 
smooth cylindrical form and is arranged to fit snugly within the bore 41. 
The rearward end 43 of the tube is threaded, as shown at 43 and is 
arranged to project slightly into the air manifold chamber 26, to receive 
a nut 44. An annular groove 45 is formed between the cylindrical central 
section 42 and the threaded rear section 43 and receives a resilient 
O-ring 46. The O-ring forms an effective barrier to prevent leakage of air 
or water along the passages 41, between the air and water manifold 
chambers 26, 27. 
A portion of the air tube 40 projects into the water chamber 26 and, at its 
forward extremity 47, the air tube is threaded for engagement with a 
mixing sleeve 48. To the rear of the threaded portion 47 is a short 
section 49 which is exposed directly to the interior of the water chamber 
26, and that section advantageously is provided with heat transfer fins 50 
to optimize heat exchange with the ambient water in the manifold 26. 
The mixing sleeve 48 is provided at its forward end with a flange 51, 
desirably of hexagonal shape to accommodate engagement by a wrench or 
other tightening tool. The flange is received in a recess 52 in the front 
face of the water manifold housing 29, and a cylindrical portion 53 of the 
sleeve, located just behind the flange 51, is received in a through bore 
54 in the front face of the water manifold. The bore 54 is aligned at the 
same angle as the bore 41 in the separating ring, to provide for the 
approximately five degrees of nominal convergence of the nozzle mounting 
assembly. 
A fluid tight seal is provided between the mixing sleeve 48 and the 
manifold housing 29 by means of a soft metal washer 55 which is positioned 
under the flange 51. 
At the forward end of the mixing sleeve, internal threads 56 are provided 
which receive an adapter nipple 57. The nipple is itself provided with 
internal threads 58 at its forward end for engagement with the threaded 
end section 59 of a snow-making nozzle 60. The nozzle 60 may be a 
standard, commercially available snow-making nozzle, advantageously a 
Veejet nozzle as made available by Spray Systems Inc. One feature of this 
nozzle is the provision in its front face 61 of a transverse, V-shaped 
groove 62 which tends to shape and flatten somewhat the dicharged 
air-water mixture. 
In accordance with one aspect of the invention, certain of the adapter 
nipples 57, shown in detail in FIG. 10, are provided with internally 
threaded forward sections 58 aligned along axis disposed at an angle to 
the primary axis 63 of the nozzle holder assembly. To provide for an 
optimum pattern of nozzle orientation about the manifold ring 25, several 
forms of adapter nipples are provided, with different angular orientation 
of the forward threaded section 58. By appropriate selection of the 
adapters, and appropriate rotational orientation thereof, the individual 
nozzles may be aligned at different angles with respect to the central 
axis of the snow machine, while permitting all of the nozzle mounting 
assemblies to be arranged at a common angle of convergence, for 
simplification of the manufacturing and assembly operations. 
As shown in FIGS. 6-8, the mixing sleeve 48 is provided between front and 
rear threaded sections 56, 64 with a mixing chamber section 65. A water 
inlet bore 66 is provided in the wall of the sleeve 48 and, as shown in 
FIG. 5, the bore 66 communicates with the interior of the water manifold 
cavity 27 such that ambient water under pressure within the cavity can 
directly enter the mixing sleeve at high velocity through the small 
passage 66. Directly opposite the water passage 66 is a threaded bore 67 
arranged to receive an anvil screw 68, which projects well into the mixing 
chamber 65 and is provided with an anvil-forming end surface 69 positioned 
to intercept the high pressure water stream flowing into the mixing 
chamber through the passage 66 to assist in breaking up the water stream 
and initiating the process of mixing and atomizing the water. In the 
operation of the system, air under pressure is simultenaously entering the 
mixing chamber 65 through the hollow air tube 40, providing for a highly 
turbulent intermixing of water and air within the chamber 65. This 
turbulent mixture then flows through the adapter nipple 57 and into the 
inlet of the nozzle 60, to be discharged at high velocity through the 
nozzle opening 70 in a somewhat flattened spray pattern determined by the 
orientation of the nozzle axis and the rotational orientation of the 
V-shaped front groove 62. 
To great advantage, the orientation of the mixing sleeves 48 in the 
air-water manifold 20 is in all cases such that the water passage 66 faces 
vertically downward to accommodate drainage of the nozzle assembly upon 
shut down of the equipment. In addition, a flat surface 71 is milled in 
the outer wall of the mixing sleeve 48 to reduce the length of the water 
inlet passage 66. This both reduces the likelihood of freeze up upon shut 
down, and facilitates remelting and/or break out of any ice blockage in 
this passage when the equipment is started up, by reason of both the 
reduced thickness and the direct exposure of this area to the ambient body 
of water within the water manifold cavity 27. 
As shown in FIG. 4, securement of the front and back manifold housings 28, 
29 to the central separating ring 30 is accomplished by means of a 
plurality of circumferentially spaced bolts 80, securing the air manifold 
housing 28 to the separating ring 30, and by means of the several nozzle 
assemblies, which serve to secure the front or water manifold housing 29 
to the separating ring. In the assembly procedure, a plurality (typically 
six) of the clamping bolts 80 are initially inserted into the separating 
ring 30, and these bolts are provided with threaded portions 81 adjacent 
the head for threaded engagement with bores 82 in the separating ring 30. 
A soft metal washer 83 underlies the head 84 of each bolt such that, when 
the bolts are tightened down against the separating ring 30, a tight seal 
is formed, and the bolts are locked relatively tightly in place, with 
their ends projecting through the ring and rearwardly. 
After installation of the bolts 80, but before installation of the air 
manifold housing 28, the front manifold housing 29 is secured in place by 
means of the several nozzle assemblies. As reflected in FIG. 5, for 
example, an assembly air tube 40 and mixing sleeve 48 is inserted from the 
front of the manifold housing 29, through aligned bores 54, 41 in the 
housing 29 and separating ring 30 respectively. When the flange 51 and 
washer 55 are seated in the recess 52, the threaded end 43 of the air tube 
projects slightly rearwardly beyond the back face of the separating ring 
30 for reception of the nut 44. When all of the air tube-mixing sleeve 
assemblies are in place, the nuts 44 can be tightened down, securely 
clamping the front manifold housing 29 into the separating ring and 
forming a sealed chamber. During this operation, the mixing sleeve 48 are 
oriented with their respective water inlet passages 66 facing downward, 
and an appropriate index mark may be provided on the exterior of the 
flange 51 for this purpose. 
After assembly and tightening of the front manifold housing 29, the rear 
housing 28 may be placed over the projecting bolts 80, which are 
sufficiently long to project slightly through the back face of the 
housing. Cap nuts 85 or the like, together with soft metal washers 86, are 
applied to tightly secure the housing 28 in the separating ring 30 to 
complete the assembly of the manifold unit 25. 
Snow-making efficiency can be enhanced by proper aiming of the several 
nozzle assemblies, as well as proper orientation of the spray fans which 
are issuing therefrom. In the illustrated arrangement, there are three 
nucleating nozzle assemblies N1, N2 and N3 (see FIG. 3) spaced more or 
less uniformly around the manifold ring 25, with the nozzle N3 near the 
lower extremity of the ring, and the nozzles N1, N2 spaced about 
60.degree. on either side of the upper vertical. The adapter nipples 57 
for the three nucleating nozzles are arranged such that their 
nozzle-mounting sockets 58 are angled at approximately seven and one half 
degrees from the primary axis of the nozzle assembly. In the case of the 
upper nucleating nozzles N1, N2, these adapter nipples are oriented to 
tilt the respective nozzles radially outward. And, since the primary 
nozzle assemblies are initially directed at a five degree convergent 
angle, the net result is an approximate two and a half degree radially 
outward divergence of the nucleating streams from these two nozzles. In 
addition, the orientation of the Veejet nozzle groove 62 is more or less 
circumferential, as shown in FIG. 3. These two upper nucleating nozzles 
serve to provide nucleation for the main air-water snow-making nozzles and 
also for a series of water jet nozzles 90, which are mounted on a water 
ring manifold 91 extending circumferentially around the upper portion of 
the manifold ring 25, spaced radially outward therefrom. 
The seven and a half degree adapter nipple 57 for the lower nucleating 
nozzle N3 is oriented to the inside, such that, taking into account the 
initial five degree convergence of the primary nozzle assembly, its nozzle 
element is directed upward at approximately twelve and a half degrees to 
the central longitudinal axis of the snow maker. 
In the upper portion of the manifold ring 25 are four spaced snow-making 
nozzle assemblies S1. These assemblies are provided with adapter nipples 
57 providing for an approximately two and a half degree canting of the 
nozzle assemblies, and the orientation of these nipples is such as to cant 
radially outward. The two and a half degree outward cant, in conjunction 
with the five degree initial convergence of the nozzle assemblies 
provides, for an approximate two and a half degree convergence of the jets 
issued by these respective nozzles S1. Likewise, the nozzle elements 60 of 
the nozzle assemblies S1 are oriented to provide for the Veejet grooves 62 
to be oriented more or less radially, and this is true with respect to all 
of the air-water snow-making nozzles in the illustrated arrangement. 
At each side of the manifold ring 25, at approximately the mid level 
thereof, are provided pairs of snow-making nozzle assemblies S2. The 
adapter nipples 57 for these nozzle assemblies are straight through, such 
that the nozzle elements themselves discharge at the primary five degree 
convergence angle at which the nozzle assemblies are mounted in the 
manifold housing. 
Slightly below the nozzle S2 are opposed pairs of snow-making nozzle S3, in 
the lower quadrants of the manifold ring. The adapter nipples for the 
lower quadrant nozzles S3 are angled at two and a half degrees to the main 
axis and are oriented radially inward, such that the lower quadrant 
nozzles S3 are directed convergently at an angle of about seven and a half 
degrees. 
Although the specific nozzle pattern illustrated and described above is by 
no means critical, it has been found to produce highly effective results 
under typical snow-making conditions. 
As illustrated in FIGS. 1 and 2, the water ring manifold 91 is secured to 
the main structure by means of brackets 92 extending from a noise 
containment shroud 100 surrounding the main manifold housing 25 and the 
nozzles mounted thereon. The water ring manifold 91 extends over a working 
arc of slightly less than 180.degree., over the upper quadrants of the 
manifold housing 25. In one advantageous embodiment of the invention, 
wherein the primary nucleating and snow-making nozzles on the manifold 
housing 25 are spaced around ten inches from the central axis of the 
snow-making unit, the water ring manifold 91 was mounted on a radius of 
about twenty inches from that axis. In the illustrated arrangement, the 
water ring manifold mounts a series of eight nozzles 90, each provided 
with an individual on-off valve 93. The nozzles 90 are water atomizing 
only--that is, there is no provision for premixing with air. These nozzles 
are used selectively as ambient conditions permit. In other words, in 
marginal snow-making conditions, the water ring nozzles 90 might be not 
used at all. With progressively lower ambient temperatures, water ring 
nozzles may be selectively opened, at the discretion and judgment of the 
machine operator, to provide for increased snow-making capacity. 
Since the water ring nozzles 90 rely exclusively on water pressure for 
atomization, the apparatus of the present invention provides for delivery 
of water to the ring manifold 91 upstream of the water driven turbine 21. 
To this end, the water supply conduit 17 connects directly to one end 95 
of the water ring manifold through a main on-off valve 96. At its 
downstream end, the water ring manifold 91 joins with a conduit 97, which 
is connected with an inlet conduit 98 for the water turbine 21. As 
described more fully in my before mentioned copending application, the 
air/water nozzles, mounted on the manifold ring 25, receive water at a 
somewhat reduced pressure, from the exhaust side of the turbine 21. 
In the operation of the apparatus of the invention, the unit is towed to 
the snow-making site, typically by a snow cat. In this respect, however, 
the apparatus of the invention is very light in weight, in relation to its 
performance, with a typical apparatus weighing less than 400 pounds. 
Accordingly, a single unit may be easily moved by a snow mobile. Snow 
cats, being more powerful can easily tow several snow-making machines. 
At the snow-making site, the equipment is connected in the usual way to the 
mountain site sources of compressed air and water. To start up the 
equipment, the main water valve 96 is opened slowly. As soon as the 
turbine motor 21 begins to operate and drive the distributional air fan, 
the main compressed air valve may be opened. The operator then adjusts the 
fan speed (by control of water flow) until the desired quality of snow is 
being produced. In this respect, the more favorable the ambient 
conditions, the higher the ratio of water to compressed air that can be 
tolerated to achieve quality snow. This is to a large extent, although not 
exclusively, a function of ambient temperature. If snow-making conditions 
are such as to accommodate full operating speed of the turbine motor 21, 
the operator may commence to turn on the water ring nozzles 90 one at a 
time, as long as the snow being produced is of adequate quality. 
In the illustrated form of apparatus, the three nucleating nozzles N1-N3 
are adjusted to issue approximately one third gallon per minute of water 
in conjunction with approximately 25 cfm of air (measured at about 94 
psi). This promotes a highly efficient crystal formation from these 
nozzles which, according to known principles, stimulates crystal formation 
in the atomized streams issuing from other nozzles. 
Depending upon ambient conditions, the turbine driven fan may be operated 
at rpms ranging from a low of approximately 1900 up to approximately 4800. 
At the lower end of this range, the effective water pressure at the 
turbine is approximately 100 psi, and this results in the discharge of 
approximately fourteen gallons per minute of water from the various 
nozzles on the manifold housing 25, in conjunction with approximately 420 
cfm of compressed air (air always being measured at a pressure of about 94 
psi). This would represent an extreme set of conditions, with barely 
marginal snow-making capability. If ambient conditions admit, water 
pressure at the turbine motor 21 may be increased up to the maximum (for 
the particular installation) of about 350 psi, achieving fan rpms of 
approximately 4800. Under these conditions, approximately 54 gallons per 
minute is issued from the primary manifold nozzles, along with air 
consumption of about 368 cfm. Ambient conditions permitting, if individual 
valves 90 of the water ring manifold are open, approximately ten gallons 
per minute of water flow is added for each such valve opened, with no 
additional consumption of compressed air. Thus, the equipment provides for 
a high degree of flexibility in use, so that maximum advantage may be 
taken of ambient conditions to achieve optimum operating efficiencies. 
The chart of air and water flow data set forth below reflects typical 
consumptions of water and compressed air at various operating speeds, in 
an apparatus of the type specifically illustrated and described herein. 
__________________________________________________________________________ 
AIR AND WATER FLOW DATA 
Flow U.S. G.P.M. at 94 PSI Air Pressure 
Water 
AIR 
Air/Water No. of Outer Ring Valves Open 
Pressure 
CFM 
RPM Ring 1 2 3 4 5 6 7 8 PSI 94 PSI 
__________________________________________________________________________ 
1900 
14 21 
27 
34 
40 
47 54 60 67 100 420 
2850 
26 33 
40 
48 
55 
62 69 77 84 150 403 
3400 
34 42 
50 
58 
67 
75 83 91 99 200 392 
4000 
43 52 
60 
69 
77 
86 94 103 
111 
250 381 
4500 
50 59 
68 
77 
87 
96 105 
114 
123 
300 372 
4800 
54 64 
74 
84 
94 
104 
114 
124 
134 
350 368 
__________________________________________________________________________ 
The apparatus of the invention provides for a commercially advantageous 
unit for mountain site snow-making operations, which, in relation to its 
performance capabilities, is lightweight and inexpensive and, perhaps more 
important, enables substantial economies to be realized in the overall 
cost of man-made snow at commercial ski areas. Because the unit of the 
present invention effectively enables the mountain site pressurized water 
system to be utilized in the driving of a distributional air fan, a high 
efficiency, high capacity snow-making unit may be provided at a fraction 
of the expense of a more conventional commercial unit. The unit of the 
invention also involves a fraction of the weight of the more conventional 
units and thus can be more easily moved from place to place at the 
mountain site for more complete and effective snow coverage. 
It should be understood, of course, that the specific form of the invention 
herein illustrated and described is intended to be representative only, as 
certain changes may be made therein without departing from the clear 
teachings of the disclosure. Accordingly, reference should be made to the 
following appended claims in determining the full scope of the invention.