US3128740A - Water jet drive - Google Patents

Description

April 14, 1964 K. H. BURGIN 3,128,740

WATER JET DRIVE I Filed May 16, 1963 4 Sheets-Sheet 1 IINVENTUR KERMIT H. BQRBIN April 14, 1964 Filed May 1e, 1963 IElErrZ K. H. BURGIN @3,128,740

WATER JET DRIVE 4 Sheets-Sheet 2 IINVENTDR KERMIT H. ELIRGIN EVM ATTURNEY Apr 4 sheets-sheet s' Filed May 16, 1963 MINIMUM] 4o 69 IIIII ss` HIIHL.

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ATTUQNEY K. H. BURGIN WATER vJET DRIVE 4 Sheets-Sheet 4 Filed May 16, 1963 lllll IINVENTDR KERMIT H. EURE-IN mY/QM m ATTURNEY United States Patent Oiiice 3,128,740 Patented Apr. 14, 1964 3,128,740 WATER JET DRIVE Kermit H. Burgin, R.R. 1, Whitestown, Ind., assigner oi eighty percent to Frederick B. Cline, Indianapolis, Ind. Filed May 16, 1963, Ser. No. 280,794 Claims. (Cl. 11S-12) This invention relates primarily to means for producing a high velocity of water through a rotatable nozzle for the purpose of driving a boat selectively in fore and aft directions and in turni g the boat in an extremely short radius. Reference is made to my copending application Serial No. 198,945 which has been allowed and is to issue May 21, 1963, under Patent No. 3,090,346. The invention herein set forth discloses a pump device unique in itself and capable of producing a greater velocity and higher volume of water flow than was possible in the structure of the above indicated copending application.

My invention herein set forth may be employed either with an outboard motor drive or an inboard motor drive as may be desired. All that is necessary for the interchange of one form of drive to the other is to replace an engine at the head of the device used in an outboard mounting by a transmission device which may be coupled to an engine within the boat for the inboard drive.

It is a known fact that when a iiuid is accelerated or given a momentum change, a force is required to produce this acceleration in the lluid and, at the same time, there is an equal and opposite reaction force which is called the thrust. The principle of jet propulsion is based on this reactive principle. Then the eiiiciency of the drive depends upon the exhaust velocity of the mass of water being hurled from the jet nozzle.

It is also well known that a properly designed centrifugal pump is ideally suited to variable speed operation which means that in a water boat propulsion device, this type of pump will operatae very well not only at high speeds, but at low speeds.

In reference to the centrifugal pump, water is admitted into a central axial zone to the interior edges of a set of moving turbine-like buckets which discharge the water by outer edges of those buckets with kinetic energy suliicient to give the desired velocity of the water through a gradually enlarging spiral passage which transforms kinetic energy into pressure energy in turn setting up the desired velocity of the water through a conduit and out a discharging nozzle. A centrifugal pump in its elemental form generally requires priming in order to ll the center zone of the buckets with water at the initial start of rotation of the buckets. It is necessary of course that the centrifugal pump as in a reaction turbine should run with all of its parts full of water.

In the present invention, a centrifugal pump of a special design is employed to have two discharge passageways from a single set of buckets. By so doing, the exit nozzles may be spaced laterally one from the other in order to counteract a rotative reaction force set up by the employment of only one nozzle. Also in the present invention, the centrifugal pump is located above the water level at the rear of the boat to be propelled, and the discharge nozzle must be above that water level in order to obtain the maximum reactive effect.

Further, in the present invention, an auxiliary auger type of pump is employed to deliver water at a predetermined velocity into the central zone of the buckets of the centrifugal pump not only in order to be assured that the spaces within the pump and between the buckets be completely filled with water at all times, but also to give an overall higher velocity of the water at the exit of the discharge nozzles.

One particular form of the invention is illustrated in the accompanying drawings, in which FIG. l is a view in side elevation and partial section of a device embodying the invention;

FIG. 2 is a view in fragmentary vertical, diametrical section through the device, on a slightly enlarged scale;

FIG. 3 is a horizontal section on the line 3-3 in FIG. 2 and on a much reduced scale;

FIG. 4 is a view in transverse section on the line 4-4 in FIG. l;

FIG. 5 is a view in transverse section on the line 5-5 in FIG. l on an enlarged scale;

FIG. 6 is a vertical sectional View on a greatly enlarged scale of the exit end of a water conduit and a discharge nozzle attached thereto;

FIG. 7 is a view in section on the line 7-7 in FIG. 6;

FIG. 8 is a View in section on the line 8-8 in FIG. 6; and

FIG. 9 is a view in transverse section on a much reduced scale on the line 9-9 in FIG. 2.

In the present form of the invention, there is employed a base generally designated by the numeral 1t) which is truste-conical in and hollow in shape. Within this base 10 there is freely, rotatively carried a second frustoconical member 11. Then within the member 11 there is a third frusto-conical member 12. This member 12, while hollow, is preferably closed at both ends against entrance of water therewithin. The third member 12 has a base 13 which is much less in diameter than is the internal base diameter of the member 11, FIG. 2. The third member 12 is substantially of the same height as is the member 11. This relationship of the two members 11 and 12 provides an annular chamber between the member 11 and 12 which decreases in volume from bottom to top.

There is a spiral lift member 14 extending throughout this annular spacing 15 between the members 11 and 12. This lift member 14 constitutes a screw-like spiral member, the inner edge of which is secured to the member 12 and the outer edge of which is secured to the wall of the member 11 so that there is a closed water passage from the bottom of the member 11 between ascending turns of the member 14 to the top open end of the space 15. As indicated in FIG. decreases from a large pitch adjacent the lower end of the member 11 to a much less pitch at the upper end.

There is a vertical drive shaft 16 extending axially through the member 12 and xed thereto in rotative driving relation. Across the lower end of the housing 10 is fixed a drive shaft bearing support member generally designated by the numeral 17. This member 17 has an outer circular liange-like ring 18 in the nature of an annulus which lits up against an outturned ange 19 about the base of the member 10. This member 17 is clamped against the ange 19 by means of bolts 20 passing therethrough, and also through an underlying flange 21 which extends from the upper portion of a water scoop generally designatedby the numeral 22. The member 17 is provided with a plurality of spokes 23, herein shown as four in number with entirely open areas 24 therebetween. The spokes 23 converge toward and are an integral part of a bearing cup 25 which carries at least one thrust bearing 26. This thrust bearing in the present form surrounds a collar 27 which extends downwardly about the shaft 16, this collar 27 being herein shown as an integral part of the base 13 of the member 12.

The upper end of the housing .10 is provided in the present showing with an outwardly extending, horizontally disposed ange 28 extending therearound. A centrifugal pump housing 29 is secured to this ange 28 by any suitable means, herein indicated as one possibility by cap screws 30.

Within the housing 29 is carried a plurality of buckets 2, the pitch of this spiral member 14 v 31 which are integrally secured to a top plate 32, FIG. 2. This top plate is provided with an upturned sleeve 33 through which the shaft 16 passes and is secured in rotative driving connection.

The housing cover plate 34 covers over the housing 29 with a close running t over the bucket plate 32, and is secured to the housing 29 in any suitable manner herein indicated as by the cap screws 35. The central area of this plate 34 is open, and an upstanding, tubular support 36 has a lower end portion surrounding this plate open ing and extends upwardly therefrom, the housing 36 being indicated herein although not necessarily so, as an integral part of the plate 34. Within the lower end portion of the housing 36, there is a transverse floor 37 against which a radial and thrust bearing 38 bears, and also fits around the collar 33 to take the radial as well as vertical upward thrust. A spacing collar 39 may be employed between the bearing 38 and the topside of the plate 32 in order to secure the desired clearance between the plate 32 and the housing cover 34. The housing member 36 may better be termed as a tubular pedestal.

The shaft 16 extends upwardly through the pedestal 36 to a device generally designated by the numeral 37 mounted on the top of the pedestal 36. This device 37 may consist as above indicated either of a driving engine or may be a transmission device for the inboard motor connection. In any event, whatever the driving motor may be is not a. part of the invention per se. The essential feature is that there be a shaft 16 available for the drive as may be selected.

Referring now to the centrifugal pump primarily, as best illustrated in FIG. 5, the central inlet opening is designated by the numeral 38a. From this opening the blades 31 curve in close proximity with adjacent blades, and then diverge widely to their outer peripheral ends in true centrifugal pump design. It is to be noted particularly that there are two scrolls 40 and 41 receiving water discharging from between the blades 31, these blades 31 constituting the buckets. Each of these scrolls extend circumferentially around the housing 29 substantially 180 degrees. The scroll 40 cross-sectional area starts from zero at the zone 42 and gradually increases in cross-sectional area to the zone 43 where the scroll merges into the discharge conduit 44. The scroll 41 starts at the zone 43 and leaves the housing at the zone 4Z to discharge into the second water conduit 45. Thus both of the conduits 44 and 45 are directed rearwardly in relation to forward drive of the boat (not shown).

On the outer ends of these conduits 44 and 45 there is rotatively carried a discharge nozzle 46, both nozzles 46 being identical, and therefore the mounting of one nozzle and its inner shape may be described in reference to FIG. 6 where but one nozzle is indicated, as attached to the conduit 44. The outer open end of the conduit 44 (as well as that of the conduit 45) turns downwardly and terminates in a plane which may range from twelve to twenty degrees upwardly from the horizontal, a fifteen degree angle being preferred. The outer circumferential edge portion ot the conduit 44 is screw-threaded as at 47.

A nozzle 48 has a bend of aproximately seventy-tive degrees where the angle of the discharge opening of the conduit 44 may be fteen degrees. The nozzle 48 has a sleeve end 49 which rotatably ts within the conduit 44, FIG. 6, with a sliding iit. This sleeve 49 in conjunction with a portion of the wall of the nozzle 48 forms a Venturi construction. The inside of the sleeve 49 curves from a thin lip edge 50 inwardly ofthe nozzle and around again back to the wall of the nozzle at a zone 51 wherein the passageway through the nozzle opens up to substantially the full cross-sectional area of that of the conduit 44.

In regard to the angles above mentioned, it is assumed that the conduit 44 before turning downwardly toward its terminal end is horizontally disposed as indicated in 4 FlG. 6. The open end of the nozzle 48 designated by the numeral 52 is substantially in a vertical plane. The angle of this plane may vary somewhat, although the vertical is preferred.

The end of the nozzle adjacent the end of the conduit 44 in addition to having a sleeve 49 tting therewithin, has an external collar 53 which fits slidingly over the end of the conduit 44 with a sliding fit so that the end of the conduit is received in eifect within a groove 54. A shoulder 55 surrounds the collar 53 and forms an abutment for a union nut 56 which is slidably carried around the collar 53 and screwhreadedly engages with the threads 47. Packing may be carried either within the groove 54, or between the free edge of the collar 53 and an abutment 57, the packing being indicated by the numeral 58.

In the normal straight ahead travel of the boat, the nozzle 48 will be in the position as indicated in solid lines in FIG. 6. However to turn the boat or to reverse it, the nozzle 48 is rotated to have the sleeve 50 and the collar 53 slide around the end of the conduit 44 engaged therebetween. Various devices may be employed for rotating the nozzle, but a simple form is herein illustrated wherein there is a shaft 59 engaged to a cross member 6) extending diametrically across substantially at the lesser diameter of the Venturi. Preferably this cross bar 60 is given a shape such as is indicated in FIG. 8 to prevent eddy currents being set up as the water ows thcrearound and therepast. The shaft 59 extends on up substantially at right angles to the bar 60, being perpendicular to the plane of rotation, and extends out through a guide boss 61 which also serves as a packing joint to have a packing 62 compressively urged against the shaft 59 by means of the nut 63.

The shaft 59 extends on above the nut 63 a distance and has a spur gear 64 fixed thereon. The two gears 64 are interconnected by a rack bar 65 slidably guided through suitable brackets 66 and 67 so that both nozzles 46 are turned in unison, that is both nozzles will simultaneously be turned to the left or to the right or downwardly as the case may be. The bar 65 is actuated in its longitudinal travel through the brackets 66 and 67 by any suitable means, one such means being indicated in FIG. 4, where there is a post 68 fixed to the bar and in turn has a cable 69 xed thereto. From the post 68 the cable 69 diverges rearwardly and outwardly to pass around pulleys 70 and 71 and thence across behind the pedestal 36 to extend forwardly to the boat for suitable operation normally connected to a steering wheel (not shown). By suitable travel of the rack bar 65, the nozzles 48 may be turned to the position indicated by the dash lines in FIG. 6 which is the position for reverse travel. In this position of each of the nozzles, the water jet is directed rearwardly and downwardly so that the jet does not strike the stern of the boat, but is directed toward the surface of the water immediately therebehind. Of course for turning to the left or right, the nozzles 48 will be turned to some intermediate position depending upon the degree of turn desired.

By reason of the peculiar construction of the centrifugal pump to have the two discharging conduits, both conduits discharging in the same direction, any torque reac tion set up by one nozzle is counteracted by the opposite rotative action of the other nozzle so that regardless of the position of the nozzles, there is no tendency for the nozzles to be so acting as to tend to rotate the entire device as above described.

Reference has been made above to the scoop 22 which is an essential part of the overall device. This scoop 22 has a housing which is generally rounded at the rear portion 73 from the flange 21, from which portion, the housing extends forwardly and upwardly as indicated in FIG. 1. On the rear of the housing there are stabilizing tins 74 vertically disposed and 75 horizontally disposed. The fin 75 serves to stabilize the depth of the device in the water upon sudden increase of water intake while the vertical n 74 tends to stabilize the boat in lateral directions making steering a smooth as opposed to an erratic operation. In the forwardly inclined portion 76 of the housing, there are a plurality of slots 77 through which rake bars 78 may reciprocate. These bars 78 are much narrower in Vwidth than is the width of the slot in each instance. Thus even though there is the presence of a rake bar 78 in a slot 77, there is suicient water intake space on both sides of the rake to supply the necessary volume of water required. These bars 78 are tied one to the other by cross members 79 and 80, and a pair of these rake bars 78 herein shown as the outermost rake bars are mounted on eccentrics 81 xed on a shaft 82 so that when the shaft 82 is rotated, these bars 78 will travel not only longitudinally of their respective slots 77, but alsoy will have an up and down action withdrawing teeth 83 on the underside of the bar upwardly through the slot. The forward end of the gang of rake bars is tied through links 84 to the housing so that the greatest lift of the bars 73 is at their rear ends. The structure so far described is a duplicate of that shown in my copending application Serial No. 203,513 entitled Water Intake Cleaner. The shaft 82 carries a bevel gear 85 which is drivingly connected to the shaft but is free to slide longitudinally therealong. The gear 85 is in a position to be selectively meshed with a bevel gear 86 fixed on the lower. end of the shaft 16, FIG. 2. The structure so far described is of course intended to be available when needed to clean olf accumulations of trash or weeds which may be encountered in driving the boat in certain types of waters, and since the boat will not always be subjected to such conditions, the rake bar 78 need not be operated continuously. In order to provide for the intermittent drive, the gear 85 as one form of a disconnecting device is shifted along the shaft 82 out of mesh with the gear 86 by an arm 87 rockably carried within the housing 22 on the lower end of a shaft 8S rockably carried to the exterior of the housing and in the present form, FIG. 1, has an upper operating lever 89 available immediately below the pump honsing 29. Thus the shaft 88 may be rotated at will depending upon whether or not there is an occasion to clean weeds oif of the intake openings of the scoop housing 22. The housing 22 has an upper extension portion 94) which will normally t up against the underside of the boat hull, so that the openings 77 extend practically to the underside of the hull and as the boat travels forwardly, water will be pulled in through these openings by action of the pump aiding movement of the boat rather than retarding it by having the scoop as a drag. Preferably the vertical fin '74 extends around under the housing to its lowest point as indicated in FIG. l as a protecting device. Itis rounded olf at its rear end for the same purpose such as in rearward travel of the boat.

Assuming that the shaft 16 is rotating in a driving manner, the combined units 11, 12, and 14 are turning in that direction which will elevate water from the scoop housing 22 upwardly to the central zone openings 38a of the blades 31. The housing 1t) will normally be submerged in the water about one-third of its height so that water is always available in the lower end portion of the space 15 to be available for this elevating action. Since the pitch of the blade 14 is reduced as the elevation increases, the elevating water will be gradually given an increased discharging speed, since the larger volume picked up at the lower end is carried upwardly to discharge through a smaller opening. The blades 31 are simultaneously turning, and water entering under pressure into the zone 38a spreads immediately out between the blades 31 where it is given added impetus and its major velocity as it leaves the outer edges of those blades 31 and enters the two scrolls 40 and 41. By entering the central neutral zone of the blades 31, there is no conllict between flow of Water entering therein and that discharge from the outer ends of the blades. It has been noted in one or two instances of prior structures that an attempt has been made to ow water to what has been termed a centrifugal pump by discharging the elevated water or water flowing horizontally directly into outer portions of the blades, and this of course nullies the normal action of a centrifugal pump. The overall diameters of the outer edges of the blades 31 are suiciently great in connection with the number of blades employed to supply suicient water to the two conduits 44 and 45 to permit the required reactive effects being had at the nozzles immediately at Venturi structure thereof. This Venturi structure not only serves to prevent sand and foreign matter from getting into the joint between the nozzle and the end of the conduit in each instance, but also aids considerably in obtaining the highest possible reactive effect immediately following the Venturi in each instance. The slight loss in pressure in passing the Venturi structure, is of little or no effect in the final reactive push, and in fact, by its location, aids in increasing that reactive effect.

The entire structure may be attached to the boat in the usual manner by a bracket connection designated generally by the numeral 100, FIG. l. This is generally hung over the transom, and is so spaced that surface 9i) will be preferably snugly against the boat hull bottom.

While I have herein shown and described my invention in one particular form, it is obvious that structural changes may be made particularly in the exterior contours of the various members, all without departing from the spirit of the invention, and I therefore do not desire to be limited to that precise form beyond the limitations which may be imposed by the following claims.

I claim:

1. A jet boat drive comprising a base member;

a centrifugal pump mounted at the top of said base and having a unit of spirally diverging blades rotatable about a vertical axis, and having a central, axial water intake chamber from which water flows between inner end portions of the blades exposed around said chamber;

a drive shaft connected to said unit and through which said axis extends;

an auxiliary screw-type pump having a rotatable unit defined by a central, inner frusto-conical member fixed to said shaft, an outer frusto-conical member, open at its base and apex ends, and a spiral screwblade winding around the outside of the inner conical member within the outer conical member, the screwblade being xed by its edges to both of said conical members thereby forming a unit lifting water between the two rotating conical members;

said rotatable unit being revoluble within said base member;

a water scoop carried by the lower end portion of said base member;

said scoop having water intake openings at its forward end in respect to forward travel of a boat;

a pair of horizontally spiralling scrolls fixed around said centrifugal pump and receiving water from said diverging vanes;

each of said scrolls extending approximately one hundred eighty degrees in a common direction, one following the other about the diverging blade unit;

a discharge conduit leading from each of said scrolls and having horizontally spaced apart discharging ends each terminating in approximately a common plane and at the same elevation therein;

said plane being inclined rearwardly and upwardly from the horizontal within the range of from ten to twenty degrees;

a nozzle rotatively mounted on said conduit end portions in each instance; to rotate about an axis normal to said plane; and

forward and downward direction. 2. The structure of claim 1, in which said conduit end portions are downwardly directed, and said nozzles are normally rearwardly directed.

3. the structure of claim 1, in which there is a sliding interconnection between each nozzle and its conduit;

said interconnection comprising a sleeve on and extending from the nozzle slidingly engaging within the conduit extending therein beyond the open end ofthe conduit; and

said sleeve forming a portion of a venturi throat, the balance of which extends into the nozzle a distance.

4. The structure of claim 3, in which said nozzle is curved from said conduit end portion through an angle of approximately ninety degrees less than the angle of said plane to have the discharge end of the nozzle in each instance in approximately a vertical plane in said normally directed positions.

5. The structure of claim 1, in which said shaft extends from a driven end portion above said centrifugal pump, through said auxiliary pump unit and enters said scoop;

a weed raking mechanism carried in said scoop externally moving weeds and grasses from said scoop water intake openings; and

means selectively drivingly interconnecting said mechanism and said shaft.

6. The structure of claim 1, in which said screw-blade has a pitch decreasing from that near the base end of the frusto-conical members to the top discharge end thereof.

7. The structure of claim l, in which said frusto-conical members have diiering wall slopes, the outer conical member sloping from base-to-top at a less angle than that of the inner conical member to provide an annular space therearound within which the spiral blade is fixed decreasing in diameter from bases to tops thereof.

8. The structure of claim 7 in which said inner conical member is closed to entrance of water therein.

9. The structure of claim 1, in which a general horizontal vane mounted on said scoop and extending rearwardly thereof; and

a generally vertical vane also mounted on the scoop;

said vanes tending to stabilize steering throughout various degrees of rotation of said nozzles.

10. The structure of claim l, in which there is means mounting said drive on a boat to locate the base end of said auxiliary pump frusto-conical members below level of water in which the boat iioats.

No references cited.

Claims (1)

1. A JET BOAT DRIVE COMPRISING A BASE MEMBER; A CENTRIFUGAL PUMP MOUNTED AT THE TOP OF SAID BASE AND HAVING A UNIT OF SPIRALLY DIVERGING BLADES ROTATABLE ABOUT A VERTICAL AXIS, AND HAVING A CENTRAL, AXIAL WATER INTAKE CHAMBER FROM WHICH WATER FLOWS BETWEEN INNER END PORTIONS OF THE BLADES EXPOSED AROUND SAID CHAMBER; A DRIVE SHAFT CONNECTED TO SAID UNIT AND THROUGH WHICH SAID AXIS EXTENDS; AN AUXILIARY SCREW-TYPE PUMP HAVING A ROTATABLE UNIT DEFINED BY A CENTRAL, INNER FRUSTO-CONICAL MEMBER FIXED TO SAID SHAFT, AN OUTER FRUSTO-CONICAL MEMBER, OPEN AT ITS BASE AND APEX ENDS, AND A SPIRAL SCREWBLADE WINDING AROUND THE OUTSIDE OF THE INNER CONICAL MEMBER WITHIN THE OUTER CONICAL MEMBER, THE SCREWBLADE BEING FIXED BY ITS EDGES TO BOTH OF SAID CONICAL MEMBERS THEREBY FORMING A UNIT LIFTING WATER BETWEEN THE TWO ROTATING CONICAL MEMBERS; SAID ROTATABLE UNIT BEING REVOLUBLE WITHIN SAID BASE MEMBER; A WATER SCOOP CARRIED BY THE LOWER END PORTION OF SAID BASE MEMBER; SAID SCOOP HAVING WATER INTAKE OPENINGS AT ITS FORWARD END IN RESPECT TO FORWARD TRAVEL OF A BOAT;

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