US3267666A - Combined marine propulsion and steering means - Google Patents

Description

Aug. 23, 1966 KiRALY ET AL COMBINED MARINE PROPULSION AND STEERING MEANS Filed Nov. 23. 1962 5 Sheets-Sheet 1 H MHHHHN 1 I l I I I IHH millil all 2 INVENTORS Arron/vs Y Jasem L /(/RAL Y BY ERNEST C. WEBB 5 Sheets-Sheet 2 J. L. KIRALY ET AL COMBINED MARINE PROPULSION AND STEERING MEANS Filed Nov. 23. 1962 all 3 34 62 Aug. 23, 1966 mm Y mg w m m V r H flA P5 5 w; JP 0 Aug. 23, 1966 J. L. KIRALY ET AL COMBINED MARINE PROPULSION AND STEERING MEANS 5 Sheets-Sheet 5 Filed Nov. 23,

Armmvay REGULATGR ELL 7 9 INVENTORS J55PH L A mAL y BY ERNEST 6. W588 aaemwqflk P 3,257,555 Patented August 23, 1966 3,267,666 COMBINED MARINE PROPULSION AND STEERING MEANS Joseph L. Kiraly, Spring Lake, Micln, and Ernest C.

Webb, Cleveland, Ohio, assignors to Lakewood Manufacturing (30., Westlake, Qhio, a corporation of Ohio Filed Nov. 23, 1962, Ser. No. 239,681 7 Claims. (Cl. 60-35.54)

Our invention relates to marine propulsion and steering by hydraulic jet means and to control mechamsm therefor, and further relates more particularly to such means which are adaptable to inboard-outboard or actual outboard use.

It is one of the objects of this invention to provide means for controlling the direction of a jet stream to effect forward, reverse, steering and/ or trim of a watercraft in motion, and to control the jet stream to effect substantial idling of the craft.

Another object of the invention is to provide means for raising or lowering the jet head and jet stream relative to the bottom of the boat whether at rest or in motion to insure smoothness, maximum control and high efiiciency.

Another object is to provide a compact control unit for jet propulsion and jet steering of a marine craft which may readily be attached to the craft as an inboard-outboard unit wherein the pump or turbine is located exteriorly of the hull or primarily as an outboard unit wherein the pump or turbine is located within the hull of the craft and has communication with the jet control mechanism located outboard of the craft.

Still another object of the invention is to provide a novel means for reversing the jet stream regardless of the directional position of the jet head and without the necessity of rotating the jet head to reverse the jet stream.

Another object of this invention is to effect a maximum of operating efficiency with a high degree of safety.

A further object of the invention is to provide a jet head construction which can be raised or lowered to selectively position the jet stream with respect to the bottom of the boat whereby to obtain maximum control and response for steering by jet at low speeds with high efficiency and performance.

Another object of this invention is to selectively position the jet stream at a relatively raised level to attain maximum performance and efliciency at high speeds.

Still another object of the invention is to provide means of the character described which will materially increase the safety and efficiency of the operation of a watercraft equipped therewith at all speeds, and to provide for quick and responsive maneuverability of the craft under running and docking conditions.

A still further object of this invention is to provide jet propulsion and steering means including a jet nozzle associated with movable flaps and means whereby the flaps may be adjusted to vary the area of the discharge opening at the nozzle and thus establish a selected relationship of jet stream pressure and volume, pump rpm. and boat speed thereby assuring maximum control and performauce of the craft.

Another object consists in the provision of jet head flaps disposed in the stream together with means for moving the flaps selectively throughout the range from closed to fully opened position to select and adjust the stream exit area through the head to obtain an optimum thrust under such conditions as the speed of the craft and the rpm. of the turbine supplying the jet stream.

Still another object of the invention is to provide means whereby a predetermined external pressure may be applied to normally urge the flaps of a jet head to closed position but which are urged toward fully opened position in response to a selected hydraulic pressure of the jet stream passing therethrough thereby to obtain maximum performance at all speeds of the craft.

A still further object is the provision of means of the above named character which is mechanically simple of construction and positive in operation.

An additional object of the invention is the provision of means whereby to manually or automatically adjust the discharge area of the jet relative to engine or pump speed, discharge pressure and/or craft speed.

Other objects and advantages of this invention will become more apparent as the following description of an embodiment thereof progresses, reference being made to the accompanying drawings in which like reference charactors are employed to designate like parts throughout the same.

In the drawings:

FIGURE 1 illustrates an inboard-outboard application of an embodiment of our invention to a watercraft;

FIGURE 2 illustrates an outboard application of an embodiment of our invention in use;

FIGURE 3 is a view in vertical section and in partial side elevation of an outboard application of the invention to a Watercraft, and is taken on line 3-3 of FIGURE 7;

FIGURE 4 is a rear end View of a jet head showing the jet flaps in one position and normally urged to relatively closed position by external mechanical pressure thereagainst;

FIGURE 5 is a view similar to that of FIGURE 4 and shows a modified form of means for adjusting the jet flaps manually and remotely;

FIGURE 6 is a section taken on line 6-6 of FIG- URE 5;

FIGURE 7 is an end view of the unit as viewed from the right in FIGURE 3;

FIGURE 8 is a diagrammatic view of manually operated control means to regulate the jet discharge area; and

FIGURE 9 is a diagrammatic view of automatic control means to regulate the jet discharge area.

In carrying out our invention, we provide as a compact unit, a propulsion and steering head of the hydraulic jet type which may readily be employed as an outboard or inboard-outboard unit secured through the transom or stem of a watercraft, as illustrated in FIGURES 1 and 2, respectively, whereby to control the direction, speed and trim of the craft by remote control within the craft itself and with a high degree of safety, ease of operation and at maximum efliciency at the will of the operator.

Referring now more particularly to the drawings in which we have illustrated an embodiment of the invention and a modified form of jet flap adjusting means, FIGURES 1 and 2 show two applications of the unit in use, and FIGURES 3, 4 and 7 show, in more detail, an embodiment which is secured outboard to the transom 1 of a boat by suitable means.

The unit includes a passageway 2 for a hydraulic fluid under pressure which may be in the form of a reversely curved tube having an inlet 3 at its lower level in communication with the discharge of a pump or turbine 4 driven by a prime mover 5, there being a screened water intake 6 for the pump.

The passageway 2 terminates in an outlet 7 communicating with a cylinder 8 suspended from and adjacent the outlet end of the passageway 2.

The bore of the cylinder 8 is substantially the same as that of the passageway 2 and the cylinder is suspended from the passageway 2 by means of a flat ring 10 which is concentric with the outlet of the passageway and which is clamped to the latter by means of a clamping ring 1'1 and a plurality of bolts 12. The flat ring 10 extends inwardly circumferentially to seat Within an annular groove 13 formed in the upper end of the cylinder 8 and thus serves to suspend the cylinder 8 within the housing 9. A

anemone packing ring 14 is interposed between the upper end of the cylinder 3 and the flange of the passageway to seal these members against leakage of fluid pressure therebetween.

The lower end of the cylinder 8 is provided with a packing supporting ring to support an annular packing 16 having sealing engagement with the inner cylinder wall 17 of the housing 9.

The housing 9 consists of that portion surrounding the cylinder 8 and a portion 18 extending upwardly beyond the passageway 2, and terminates in a support 19 for control means such as a trim control, a reverse control, and the tiller, as will be more fully described hereinafter.

The lower portion of the housing 9 surrounding the cylinder 8 carries a jet head or nozzle which is indicated generally at 20 and which is rotatably mounted within the housing for substantially a full 360 rotation in response to a manipulation of the tiller arm 21.

The jet head 26 is mounted within the lower housing 9 for rotative movement about a substantially vertical axis, there being a ring type ball bearing 22 carried in the lower housing 9 and in the jet head 24). A lubrication duct 23 is provided to communicate lubricant from a source of supply to the bearing 22. Suitable removable clamp rings for the bearing, one of which is carried by the jet head 24}, as indicated at 24, and the other of which is carried by the lower end of the housing 9, as at 25, are provided as illustrated in FIGURE 3. These clamping rings each carry packing rings 2d to seal the relatively movable housing and jet head against fluid pressure leakage.

The jet head 20 as a unit is not only rotatable through substantially a full 360 within the housing 9 but is also adjustable as a unit with the housing 9 and the upwardly extending colum 1% along the common vertical axis of these members.

The jet head 20 is a substantially hollow member communicating with the incoming fluid pressure passing from the passageway 2 through the cylinder 8 and is provided with a discharge nozzle, as indicated generally at 27, to direct the jet fluid pressure rearwardly of the jet head and the craft to which it is attached to impart forward motion to the craft when the head is in the position shown in FIGURE 3. The jet head is also provided in this position with a forwardly disposed discharge nozzle or opening 28 through which the fluid pressure may be diverted by means of a rockable reversing vane 29 which may be actuated to close this forward opening 28 during jet propulsion of the craft in a substantially forward direction, as shown, but which is operable to open the forward discharge 28 and to close the rear discharge opening 27 to divert the jet discharge 180 with respect to the rear discharge so as to impart reverse movement to the craft, as illustrated in the broken line position of the reversing vane 29.

The vane 29 may also be positioned between the limits of its movement to a point where the fluid pressure column entering the jet head from the cylinder 8 may be divided and directed simultaneously partly to the forward nozzle opening 27 and partly to the rear nozzle opening 28 to effect neither a decided rearward nor a forward movement to the craft by substantially equalizing the thrust of the stream is opposite directions, thus permitting idling of the craft even during operation of the turbine impeller.

The rear jet discharge end of the nozzle is provided with a plurality of flaps 30 pivotally carried at 31 and extending rearwardly from the pivots where they are connected at their rear ends to an adjusting yoke 31'. Intermediate the flaps 30 is a rocker arm 32 pivotally carried at 33 in the jet head or nozzle wall adjacent thereto, the portion 34 of the rocker arm member extending forwardly toward the craft where it is pivotally connected at 35 with one end of a connecting link 36. The portion 34 of the rocker arm 32 extends rearwardly for connection with the yoke 31. The opposite end of the connecting link is pivotally connected at 37 with a stud 38 which is secured to the outer tube 3? near thelower end thereof. The outer tube 39 carries within it an inner tube 49 in telescopic fashion and these tubes are relatively movable along the longitudinal axis thereof and terminate at their upper ends, one below the other. Each of the upper ends of the outer and inner tubes is provided with a collar carrying ring 41 on which is mounted a collar 4-2 having an annular groove or channel 43 for receiving the inner ends of diametrically opposed pins 44 carried by the arms %5 of a crank pivotally mounted on a wall as which is detachably suspended below the head 47 of the column 18 by means of bolts 48.

One crank (indicated at 49, is pivotally carried in a wall of the column, as at St and carries at its upper free end a pivot pin 51 by which the control and operating rod 52 is operatively connected to the crank. The crank 53 is pivotally mounted at 54 in the wall 46 and extends upwardly terminating in a pivot pin 55 by which the control and operating rod 56 is pivotally connected with this crank.

Telescopically carried within the inner tube or sleeve it) is an actuating rod 57 which extends upwardly beyond the upper extremity of the inner tube or sleeve for keyed connection with the tiller 21, as indicated at 53. The rod 57 extends below the lower extremity of the inner tube or sleeve 41? and has a lower portion reduced in diameter, as indicated at 60, and is secured in a seat 61 formed in the base of the jet head whereupon rotation of the rod 57 about its vertical longitudinal axis will impart angular rotation to the jet head.

We provide means supported by the lower end of the cylinder 4%) and which is responsive to axial movement of the sleeve to effect a 180 reversal of the jet stream to selectively control forward and rearward motion of the craft to which the mechanism is applied.

This last named means includes a gate or vane 29 which is pivotally connected at the jet head 62 and which has a rearwardly extending portion 63 and a forwardly extending portion 64. It will be seen from FIGURE 3 that this gate is rockable about the pivot 62 and that such motion is imparted by means of a link 65, pivotally connected at 66, to a support 67 which is fixedly connected upon the outer wall of the inner sleeve or tube 49 at its lower end and is connected at 68 to the forward end of the gate.

It will be noted that relative movement of the telescoped sleeves 39 and 40 along their longitudinal axes in effecting an adjustment of the flaps 3t? and in actuating the reversing vane w respectivcly, with respect to the tiller rod 57, is permitted by the provision of slots 70 and 71 in the sleeves 39 and 4%, respectively, in which a headed stud 72 carried by the tiller rod 57 travels. Since the limits of longitudinal movement of the sleeves 39 and 40 may not necessarily be the same, these slots 7t) and 71 may be of such length as to individually permit suflicient movement of the respective sleeves to accomplish the proper flap adjustment and to actuate the reversing vane to either of its extreme positions, either to close the forward opening and open the rear opening in the jet head to effect forward travel of the craft, or to close the rear opening and open the forward jet opening to effect a reversal of travel.

In this connection, by virtue of the stud 72 operating in the slots 70 and 71, any angular rotation imparted to the tiller rod 57 will swing or rotate the jet head 20 for effecting a predetermined steering course without in any way interfering with the simultaneous adjustment and movement of the flaps or the reversing vane.

A suitable packed bearing 73 is provided for properly supporting the telescopic tube and rod assembly for relative movement therein.

We have also provided means whereby the jet head may be lowered or located with respect to the hull bottom to selectively position or locate the jet stream to obtain maximum control and response for steering at relatively low speeds at high efiiciency and performance, or to raise the level of the jet stream to attain maximum performance and efiiciency at high speeds. Referring more particularly to FIGURES 3 and 7, such means may include a control lever fulcrumed at 74 to the member 2 and having an arm 75 extending upwardly for pivotal connection with the control rod 76. A forked arm 77 of shorter length extends rearwardly and is pivotally connected at its free forked ends at 78 with the upper ends of links 79. The lower ends of the links are pivotally connected at 80 with a portion of the housing 9. Cushioning stops 81 are mounted on the member 2 and are in the path of movement of the forks 77 to limit their downward movement when lowering the housing and jet head assembly to the broken line position in FIGURE 3.

As will be observed from FIGURE 3, the housing 9 and the cylinder 8 are relatively movable along their common longitudinal axis in raising and lowering the housing, jet head and control assembly. In this manner, by manipulation of the control rod 76, the vertical position of the jet head with respect to the hull bottom is easily and quickly selected without interference with the operation of the flap control or the angular position of the head about its longitudinal axis, whether the craft is docked or running.

Again referring to FIGURE 3, we have illustrated one form of means whereby the jet flaps are normally urged to a substantially closed position by a predetermined mechanical force of compression thereagainst, but which will automatically open in response to the force of hydraulic pressure and volume of the water flow as it passes from the outlet of the jet head and between the flaps.

Thus a balanced relationship or ratio is established between the volume of flow and forces of compression imposed upon the fiaps both mechanically and hydraulically resulting in maximum and eflicient control and performance at all speeds.

In this connection, a selected mechanical force of compression is imposed on the flaps to normally urge them to substantially closed position by opposed compression springs 82 carried in the opposed cylinders 83 and axially along the yoke rods 31'. The cylinders are in turn mounted on the arms 32 and the respective flaps 30. The force of compression of the springs 82 can be adjusted by the adjusting nuts '84.

In FIGURES 5 and 6, we have illustrated an alternative form of means for adjusting the flaps, which may be manually or mechanically operated from a remote point by :means of a cable or Bowden wire 90 operating in a tube 91 mounted on the jet head and .has a control handle, knob or other suitable means at its remote end (not shown) by which the cable or wire may be rotated and/or axially moved within the tube.

The cable or wire is connected at its lower end to a head 92 carried on the upper end of a screw member 93 having right and left hand threads as at 94 and 95 operating in correspondingly threaded connectors 96 mounted on the flaps 30 The adjacent ends of the right and left hand screws are coupled for rotation in a yoke 97 carried on the outer end of the arm- 98 which in turn is pivotally supported at 99 in the exit opening of the jet head 20.

Thus the ratio of pressure and volume can be con trolled by opening or closing the jet flaps to selectively enlarge or restrict the area of the exit opening of the jet head.

The operation of our invention may be described as follows:

With the turbine running to supply water under pressure through the passageway 2, the cylinder 8 and the jet head 20, land if it is desired to drive the watercraft forward by jet stream, the vane or gate 29 in the full line position in FIGURE 3 will close the reverse exit in the head and will open the forward exit to the flaps 30. With the flap adjusting means set as shown in this figure, the jet flow will, of course, exit between the lfiaps and, depending upon the selected force of compression of the springs 82, a balanced pressure and volume ratio will be established at different horsepower input values.

Thus the craft is driven forwardly at a speed determined by the pressure-volume ratio of the jet stream. The higher the adjustment of the jet and control assembly, that is, the nearer to the surface of the water medium supporting the craft, the higher the speed of the craft and, conversely, the lower the position of the jet stream, the slower the speed at a given volume-pressure ratio, but in both instances and at all speeds, the maximum of performance and efficiency of operation is assured.

The jet stream also is utilized for steering the craft by virtue of the provision of a rotatable jet head and control means by which the head may be angularly rotated through substantially a full 360 by the tiller 21 Without impairing the volume-pressure balance.

To operate the craft in reverse without rotating the head 180 from the position shown, it is merely neces sary to actuate the control rod 56 to slide the sleeve 40 downwardly. This will cause the vane or gate 29 to assume the broken line position in FIGURE 3, opening the reversing exit of the head and closing the forward exit. The jet stream will then be directed forwardly toward the craft to move it at a reduced speed in reverse.

By operating the control rod 52, the outer sleeve 39 may be moved along its axis to trim the angular disposition of the flaps 30 whereby the craft may trim its bow upwardly by lowering the sleeve 39 to tilt the flaps upwardly, or the bow may be brought lower in the water by trimming the flaps or vanes 30 in an opposite angular position. In either instance, the trim may be effected without disturbing the pressure-volume ratio acting on and through the flaps.

In FIGURE 8 we have illustrated diagrammatically a control means whereby the area of the jet stream at its discharge from the jet head may be regulated by adjusting or setting the angular positions of the flaps 30 or 30 in the manner described hereinbefore either by the selected compression of the springs 82 or by turning the screws 94 and 95, respectively.

This control of the jet discharge area in relation to the rpm. of the pump 4, the fluid pressure in the jet head just before discharge, and the speed of the craft, may be accomplished manually or automatically.

More specifically, in FIGURE 8, we have illustrated an indicator at 100 conveniently located and which by means of a pointer 101 movable over a scale 102, graduated to indicate setting of the relative angular positions of the flaps 30 or 30 will enable the operator to determine the angular disposition of the flaps and thus the selected discharge area of the jet.

By correlating the flap position or discharge area of the jet with the rpm. of the pump by means of the indicator 103, the fluid pressure indicated on the pressure gauge 104 through suitable pick-up means 105 exposed to the interior of the jet head adjacent the flaps but upstream thereof, and/or the craft speed indicated on the meter 106 having connection with a pick-up tube 107 submerged in the water with its intake pointed in the forward direction of the boat, it will be seen that the operator has merely to observe the indicators 103, 104 and 106 and adjust the angle of the flaps 30 by turning the knob 108 which is geared to the pointer shaft on the indicator 102, simultaneously actuating the Bowden wire to set the flaps.

While we have shown and described manual means for correlating the flap position to the pump r.p.m., the fluid pressure in the head and/or the craft speed, it is within the intent of this invention that suitable means may be employed to automatically provide for such correlation.

A typical means for automatically correlating the variables of craft speed, jet chamber pressure and engine rpm. in relation to the area of jet discharge opening is illustrated diagrammatically in FIGURE 9. In this arrangement, an hydraulic or pneumatic positioning unit 109 is employed to position the knob 108 governing the area of the jet discharge opening in relation to the fluid pressure in the line 110 which is connected at one end with a fixed fluid pressure supply. Suitable bleed-type regulators 103*, 10 and 106 are actuated by changes in the rpm. of the engine, the fluid pressure in the jet chamber and the craft .speed, respectively. The eifect of each of these regulators on the positioning unit 109 may be individually varied by adjustable means 111 and the overall effect on the pressure at 110 is modified by adjustment means 112.

It will be seen that by manually or automatically selecting the several relationships With the cross sectional area of the jet discharge, efficient operation, maneuverability and control of the craft under all conditions is assured.

Various changes may be made in the details of con struction and arrangement of parts of the invention without departing from the spirit thereof or the scope of the appended claims.

\Ve claim:

1. Marine propulsion and steering means for a watercraft comprising a housing having a fluid passageway therein with a fluid pressure inlet thereto, a jet head car ried in said housing and communicating with said passageway, said head being movable in said housing along and about a substantially vertical axis for jet running depth regulation and steering, respectively, said jet head having forward thrust and reverse thrust openings, means in the jet head for selectively directing the fluid pressure to either the forward or the reverse openings, means in the jet head for directing the fluid pressure about a horizontal axis for watercraft trim control, and for maintaining a balanced fluid-volume pressure ratio through at least one of said outlets.

2. In hydraulic jet propulsion and steering means for watercraft, a jet head adjustable along and rotatable about a substantially vertical axis, a source of hydraulic fluid under pressure, a passageway connecting the head with the fluid pressure source, said head having an outlet for the jet stream, a plurality of flaps pivotally mounted in the outlet and movable differentially to adjust the outlet area whereby to control the volume-pressure ratio and thrust of the jet leaving the head, means for coupling the flaps, and means for angularly adjusting the coupled flaps to trim the craft about a substantially horizontal transverse axis.

3. The invention as set forth in claim 2 and coupled flap drive means automatically responsive to the variables of craft speed, jet chamber outlet pressure and engine rpm. to actuate the coupled flaps to thereby correlate the outlet area with the said variables, and means for indicating the angular disposition of the coupled flaps with respect to the outlet opening of the head.

4. The invention defined in claim 2 in which the coupled flap angular adjusting means includes a remote flap position indicator, a control means having driving connection with said coupled flaps and with said indicator whereby the flap angular position may be simultaneously controlled and visibly displayed at a location remote from the flaps.

5. The invention defined in claim 2 with remote control drive means for varying and determining the angular position of the flaps with respect to the jet head outlet opening including a flap angle position indicator, drive means connecting the flap angle position indicator with the flap tilting means, and means for indicating engine r.p.m., craft speed and jet outlet opening area, said last indicator means determining the desired angular setting of the flaps.

6. In hydraulic jet propulsion and steering means for watercraft, a jet head having a jet directing outlet, a source of hydraulic fluid under pressure, a tube having a passageway connecting the head with the fluid pressure source, a support mounted on and movable relative to the tube, said jet head being rotatably carried in said support, means for raising and lowering the support and jet head as a unit with respect to the tube, a plurality of flaps pivotally carried in the jet head outlet opening, means for tilting the flaps in unison, means for exerting a selected initial force of compression against said flaps to urge them toward closed position, and control means on the support for moving the jet to a selected position in angular rotation.

7. In hydraulic jet propulsion and steering means for watercraft, a jet head having opposed jet directing outlets, a tubular member for communicating fluid under pressure from a source to the jet head, a gate movable to selectively open one outlet and close the other outlet, a support mounted on and movable relative to the tubular member, said jet head being rotatably carried in said support, means for selectively turning, raising and lowering the support and jet head as a unit with respect to the tubular member, a plurality of flaps pivotally carried in one of the jet head outlet openings, means for tilting the flapsin unison, means for exerting a selected initial force of compression against said flaps to urge them toward closed position, control means on the support for moving the jet to a selected position in angular rotation, and means on the support for actuating said gate.

References Cited by the Examiner UNITED STATES PATENTS 1,842,858 1/1932 Couzinet 115l2 2,243,800 5/1941 Goodyear 6035.54

2,671,620 6/ 1948 Andrews .s 244-767 2,488,174 11/1949 Clegern.

3,040,523 6/1962 Price 6035.6

3,040,525 6/1962 Cochran 60-3555 3,040,527 6/1962 Christensen et al. 6035.55

MARK NEWMAN, Primary Examiner.

SAMUEL LEVINE, Examiner.

T. BLUMENSTOCK, RD. BLAKESLEE,

Assistant Examiners.

Claims (1)

1. MARINE PROPULSION AND STEERING MEANS FOR A WATERCRAFT COMPRISING A HOUSING HAVING A FLUID PASSAGEWAY THEREIN WITH A FLUID PRESSURE INLET THERETO, A JET HEAD CARRIED IN SAID HOUSING AND COMMUNICATING WITH SAID PASSAGEWAY, SAID HEAD BEING MOVABLE IN SAID HOUSING ALONG AND ABOUT A SUBSTANTIALLY VERTICAL AXIS FOR JET RUNNING DEPTH REGULATION AND STEERING, RESPECTIVELY, SAID JET HEAD HAVING FORWARD THRUST AND REVERSE THRUST OPENINGS, MEANS IN THE JET HEAD FOR SELECTIVELY DIRECTING THE FLUID PRESSURE TO EITHER THE FORWARD OR THE REVERSE OPENINGS, MEANS IN THE JET HEAD FOR DIRECTING THE FLUID PRESSURE ABOUT A HORI-

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