Hand operated suction dredge head and hydraulic submersible pump assembly

A portable and lightweight suction dredge head which is held by a diver and is hand operated so as to be easily moved about in the working position. These heads are, for example of sizes from three inches to eight inches in intake diameter. The dredge head is used for excavating under water and is of the suction type wherein the material is conveyed away from a suction pipe from the dredge head. A jet digger may also be used with the dredge head. A manually operated valve on the dredge head permits the operator to regulate the amount of suction at the inlet of the dredge head and is capable of reducing the amount of suction so as to permit the operator to (1) adjust the density of the material being conveyed, that is regulate the amount of sludge or trash relative to the amount of water that is being conveyed, (2) control the digging aggressiveness of the dredge head, or (3) easily remove foreign material such as rocks, cans or other matter from the inlet of the dredge head or free his hand or foot if it accidently is grabbed by the dredge head. The head is rotatably mounted on the suction pipe which leads to a remote location whereby the head can be easily rotated at the most desirable digging position, and means are provided for insuring that the swivel coupling remains clear of sand or the like and freely operative. The above dredge head together with a hydraulically driven submersible pump assembly act to eliminate pump priming difficulties and pump sealing problems due to abrasive material, and provides good net positive head, horsepower, speed control, safety and mobility.

BACKGROUND OF THE INVENTION 
Various underwater mining devices, dragheads or earth moving suction 
nozzles have been provided for the purpose of excavating underwater by 
means of suction, with or without jet diggers, or for mining or in situ 
disintegration of material below the surface of the water. These devices 
usually form part of the large apparatus which is moved about as part of 
large excavating equipment. One example of that type of hydraulic suction 
nozzle is shown in the U.S. Pat. No. 2,774,569 issued Dec. 18, 1956 and 
entitled "Earth Moving Hydraulic Suction Nozzles" and wherein the clogging 
of these nozzles by rocks or other objects is acknowledged as a chief 
cause of difficulty. In that particular patent, the tubular nozzle has 
strainer bars and a helical spring at its inlet end in an attempt to 
remedy that difficulty, however, such an arrangement tends in itself to 
restrict the in-flow of the material to be removed and becomes clogged 
itself. Another example of an "Underwater Mining Device" is shown in the 
U.S. Pat. No. 2,605,090 issued July 29, 1952. That device can be used only 
for picking up small objects, such as particles of gold or other precious 
metals underwater and has a very small nozzle area to suction pipe area 
for that purpose. 
A third type of prior art device is shown in U.S. Pat. No. 2,280,066 which 
issued Apr. 21, 1942 entitled "Draghead For Dredging Apparatus" in which 
the draghead is used and a central water supply is used to relieve the 
pressure of the draghead on the surface of the river channel to effect a 
scouring action. 
The above and other prior art devices have had certain shortcomings, among 
which is the fact that they are incapable of being firmly and positively 
controlled by the operator who must hold the dredge head in his hands and 
work for considerable periods of time in a sometimes dark location and 
under difficult circumstances. 
Other type prior art dredging apparatus such as air lifts or hydraulic 
lifts have not been satisfactory because, among other things, of their 
lower head capabilities, poor capacity and inability to use them in any 
position. 
SUMMARY OF THE PRESENT INVENTION 
The present invention provides a portable, light-weight, hand operated, 
suction dredge head which the operator can positively, accurately and 
easily control as to its functions. The dredge head provided by the 
present invention includes a tubular section nozzle having an inlet end 
including a gridwork that prevents the entry of foreign material into the 
nozzle. At the other end of the suction nozzle is located a hand operated 
valve which adjusts the amount of water admitted into that end of the 
suction nozzle and consequently adjusts the amount of suction at the inlet 
of the suction nozzle. The size of these hand operated heads, by way of 
example, are only from three to eight inches in nozzle diameter. The 
dredge head further includes a discharge branch extending from the suction 
nozzle intermediate its length and through which the material from the 
suction nozzle is discharged into a suction pipe that leads to a rather 
remote discharge area. A swivel or ball type coupling is provided between 
the dredge head and the discharge suction pipe which permits rotation or 
complete swivelling action of the head by the operator. The swivel or ball 
joint coupling is easily connected and disconnected and means are 
furthermore provided for using the action of the moving water which is 
being discharged to flush the coupling clear by this jet pressure and 
prevent its "freezing" due to accumulation of sand or the like. Optional 
means may also be provided on the suction nozzle for providing a jet 
digging action at the area of the nozzle intake to thereby assist in 
digging and loosening the material to be excavated. 
In operation, the present hand dredge nozzle acts to pull itself toward or 
into the area in which it is digging, that is, the nozzle attempts to "get 
away" from the operator. 
A valve is provided for adjusting the amount of suction at the inlet of the 
nozzle, and by opening the valve to the desired degree, the suction effect 
of the nozzle can be reduced thus acting to balance the aggressiveness of 
the nozzle for better operator control. This valve has spring biasing 
means to prevent oscillation or "chatter" of the valve. Replaceable 
bushings are also provided for mounting the valve in the nozzle and for 
maintaining the valve in an adjusted position without further attention 
from the operator. 
In this manner, the present hand operated dredge has means by which the 
flow passing through the dredge can be quickly regulated, more 
specifically, the suction at the inlet of the dredge can be quickly 
adjusted for good control characteristics, which permits restrictions to 
be removed from the inlet area, which permits the operator to free his 
hand or foot which may accidently be engaged by the nozzle, and which 
furthermore and importantly permits the operator to vary the sledge/water 
ratio being conveyed through the dredge, that is, to in effect vary the 
"density" of the material being removed. This complete and positive 
control of the dredge is necessary because the operator must often depend 
only on the sound or vibration of the dredge head to ascertain its 
characteristics and operating conditions as above mentioned. 
A jet digger attachment may also be provided for the above mentioned hand 
dredge nozzle, which attachment can also be adjusted to help regulate or 
"balance" the digging aggressiveness of the nozzle by counterbalancing its 
downward thrust, thereby making the nozzle more easily controlled by the 
operator. In addition, the jet digger attachment stirs up and agitates the 
surrounding material, thereby aiding in its excavation. 
The present invention also provides a dredging system which includes the 
above mentioned suction dredge head when used in combination with a 
hydraulically driven submersible pump assembly and which system eliminates 
pump priming difficulties and also pump sealing problems due to the 
abrasive material being handled, and which system furthermore provides 
good net position suction head, horsepower, speed control, safety and 
mobility. 
These and other objects and advantages of the present invention will appear 
hereinafter as this disclosure progresses, reference being had to the 
accompanying drawings.

DESCRIPTION OF A PREFERRED EMBODIMENT 
The present invention finds particular utility in working in restricted 
areas and for rather localized excavation. For example, certain underwater 
pumping equipment sometimes becomes lost or buried in the floor of the 
body of water and is difficult, if not impossible to retrieve. An example 
of this type of equipment are trash pumps TP shown in my U.S. Pat. No. 
3,910,728 issued Oct. 7, 1975 and which pumps sometimes dig themselves 
into and bury themselves in the floor of the lake or ocean. The present 
invention is utilized to follow the hydraulic lines of such a pump 
downwardly into the ground and find the pump by excavating the area around 
it. Furthermore, these dredging operations occur in places where 
visibility is very poor and the operator must have complete control of the 
dredge head to be able to manipulate it easily and quickly and positively 
in any direction. Frequently the inlet of the dredge head becomes clogged 
with foreign material and due to the suction in the inlet, it is difficult 
to remove the foreign material or the operator's hand or foot if caught in 
the nozzle. 
The present invention can be used in many underwater environments such as 
shallow ponds, lakes or excavations. As shown in FIG. 1 however, it is 
shown as used in connection with a vessel on the surface of the water, 
such as a barge B on which is located the power source PS for operating 
the hydraulically operated submersible pump HSP located underwater and 
which in turn is connected to a flexible suction conduit 3. Conduit 3 is 
connected to the discharge of the dredge head DH. The power source may 
take the form of the power source PS shown and described in my said U.S. 
Pat. No. 3,910,728 and which includes an internal combustion engine E that 
drives a positive displacement pressure fluid pump 2 that directs pressure 
fluid via flexible conduit 2a to a hydraulic motor 4 on the hydraulically 
operated submersible pump HSP. Flexible conduit 2b returns the fluid to 
the reservoir tank T of the power source PS. The hydraulic motor 4 drives 
the pump impeller I (FIG. 6) to move water and sludge through conduit 3 
and then pump it through discharge conduit 3a to a location above the 
water surface and which is remote from the dredge head DH. The hydraulic 
submersible pump has a plate 5 secured across its inlet side and a nipple 
5a extends therefrom for attachment to conduit 3. 
Conduit 3 has an inlet end 3b which is adapted to be swivelly connected to 
the dredge head DH to be described. FIG. 1 shows the operator 6 in the 
working position and who is furnished oxygen for his diving equipment via 
line 7 from the compressor and oxygen source 8 on the barge. It should be 
mentioned that an operator utilizing the dredge head of the present 
invention may often work for hours beneath the surface of the water. 
The dredge head DH provided by the present invention is preferably made 
primarily of an aluminum alloy and is lightweight and easily portable by 
the operator. Furthermore, the dredge head DH is rather compact and 
relatively small and has all of its parts within easy reach of the 
operator. Furthermore, the arrangement and construction of the parts of 
the dredge head are such that the operator can control the dredge head in 
the operating position and thereby positively and accurately control its 
functions and components. 
More specifically, the dredge head includes an elongated tubular section 
nozzle 10 having a lower end to which is welded or otherwise secured a 
shield or grill 11 fabricated from aluminum alloy rods. This grill 
prevents relatively large material such as rocks, cans or other foreign 
material from entering the dredge head. The upper or opposite end of the 
tubular section nozzle is relatively open except for the rods 12 welded 
thereacross which prevent inadvertent entry of material therein. Adjacent 
the upper end of the suction nozzle 10 is a circulate plate, butterfly 
type valve 14, fixed to and oscillatably mounted on its shaft 15. Shaft 15 
is mounted in bushings 16 mounted in the suction nozzle 10. A U-shaped 
operator's handle 17 is fixed to the shaft 15 by bolts 19 extending 
through the cup-shaped members 18 that in turn are welded to the handle. 
Spring 20 is located within one of these cup-shaped members and urges the 
valve assembly in one direction to prevent oscillation and chatter of the 
valve when the head is operating. The bushings 16 act to hold the valve in 
any one of its positions to which it has been adjusted by the operator. 
The valve is swingable to any one of a number of adjusted positions 
between a closed position where it prevents water from entering the upper 
end of the nozzle to a fully open position where water can freely enter 
the upper end of the nozzle due to the suction in the conduit 3. Bushings 
may be of brass or resilient material. 
The dredge head also includes a tubular discharge branch 24 which is welded 
to the tubular suction nozzle 10 intermediate the length of the latter and 
is thereby in fluid communication therewith. It will be noted that the 
branch 24 extends at an angle to the nozzle 10 which, as indicated in FIG. 
1, places the nozzle at a convenient working angle relative to the 
operator straddled thereover. The rear or discharge end of the branch 24 
is secured to the inlet end of the suction conduit 3 by means of a swivel 
coupling 24 that includes an annular collar 27 formed on the end of the 
branch 24 and which receives a ring 28 secured on the end 3b of the 
suction conduit 3. The ring 28 has a groove 29 around its periphery in 
which the inner ends 30 of the clamp 31 are engageable. This groove and 
clamp connection provides a swivel connection between the dredge head and 
the suction conduit 3 so the head can be rotated relative to the conduit 3 
by the operator to any suitable position. 
A jet digger attachment 35 may be provided on the nozzle and has discharge 
ends 36 through which fluid, such as air or water, under pressure is 
discharged into the area being dredged to thereby stir up and agitate the 
material to be pumped and facilitate its excavation. A pressurized water 
pipe 33 furnishes the pressurized air or water to the jet digger 
attachment 35 and a valve 34 is provided for operator adjustment of the 
flow. For instance, this "jet fluid" is provided at a pressure of 90-150 
p.s.i. for example, which is required for working with hard mud. On the 
other hand and if silt is being excavated, the "jet fluid" attachment may 
not be needed. This jet digger attachment can also be used to regulate the 
aggressiveness of the nozzle by counterbalancing the downward thrust of 
the nozzle, also rendering the nozzle easy to control by the operator. 
A pair of U-shaped handles 40 are welded to the discharge branch 24 and the 
operator can conveniently grasp these two handles and firmly hold the 
dredge head for manipulation to any desired digging position. It should be 
noted that both the handle 17 and the handles 40 have no free ends around 
which air, suction or other lines can become entangled and this is 
important in operations of the type where the present invention finds 
great utility. The handles 40 afford the operator positive and complete 
control of positioning and operating the dredge head and provides a good 
attitude of the working end of the dredge head relative to the operator 
with complete visibility thereof. 
As shown in FIG. 5, the handles 40 are tubular and have their ends 41 and 
42 in communication, respectively, with the interior of the swivel joint 
formed by the swivel coupling and the interior or branch 24. Water which 
may contain foreign material such as sand, mud, gravel or the like, seeps 
into the joint from the outside of the dredge head and is thus caused to 
flow through the handles and then be discharged as shown in the 
curvilinear arrows into the discharge branch. This jet pressure of the 
water which is provided by the flow of water through the discharge branch 
acts to flush the swivel joint and prevent accumulation of sand and the 
like and keeps the swivel coupling clear of foreign matter to insure free 
operation of the joint. 
OPERATION 
If the inlet end of the dredge head becomes obstructed by foreign material 
such as rocks, cans or other debris or if his hand or foot is accidently 
engaged by the nozzle, the operator can move the valve 14 simply by 
swinging the handle 17 to an open or partially open position which 
immediately reduces the suction at the inlet of the dredge head and 
thereby permits the operator to remedy the problem. Once the nozzle is 
unobstructed, the operator can immediately close the valve to reinstate 
the suction forces at the inlet of the dredge head. 
The butterfly valve 14 permits the operator to quickly vary the digging 
aggressiveness of the nozzle and affords good control thereof. 
Even though the operator may be working in a dark location, if the inlet of 
the dredge head becomes clogged or if too much sludge is being conveyed in 
comparison to the amount of water being conveyed, he is able to ascertain 
that by the sound or he can feel it because of the vibration or rumbling 
of the dredge head and accordingly can vary the density of the 
sludge/water being conveyed. 
The present invention permits the operator to remedy any problems with the 
dredge head at the source of the problem rather than signalling the barge 
operator of any trouble. The present dredging apparatus with the dredge 
head located on the inlet side of the submersed hydraulically driven pump 
and the pump HSP being located beneath the surface, insures that pump 
priming problems are avoided. 
The present invention provides a particularly efficient dredging system 
having a hydraulically driven submersible pump acting to provide the 
suction for the portable hand operated dredge head and which results in 
relatively low power requirements and eliminates pump priming difficulties 
in prior art dredging apparatus. Furthermore, the present dredging system 
is safe in operation, capable of good operator control, eliminates seal 
failure of the submersible pump due to abrasive material being conveyed, 
is highly mobile and is highly efficient in providing good positive 
suction head.