US2834313A - Marine propelling and steering mechanism - Google Patents

Description

May 13, 1958 w. o. FROHLICH 2,334,313

MARINE PROPELLING AND STEERING MECHANISM Filed Oct. 19, 1955 4 Sheets-Sheet 2 INVENTOR.

Wll-kY 0. FROHLI H BY XWK May 13, 1958 w. o. FROHLICH MARINE PROPELLING AND STEERING MECHANISM 4 Sheets-Sheet 3 Filed Oct. 19, 1955 ooocooo H m L m w w m 2 6 m o m m & u w I!!! 1 W v 0 9 xm v y 1958 w. o. FROHLICH 2,834,313

MARINE PROPELLING AND STEERING MECHANISM Filed Oct. 19, 1955 4 Sheets-Sheet 4 INVENTOR.

WH-LY o. FROHLICH nTmQnx-II MARINE PROPELLING AND STEERING MECHANISM Willy 0. Frohlich, Philadelphia, Pa.

Application October 19, 1955, Serial No. 541,425

8 Claims. (Cl. 115-35) This invention relates generally to propelling and steering mechanisms for marine vessels and particularly to improvements in the construction and design of an inboard type of such mechanism.

A principal object of the present invention is to provide for a marine vessel an inboard propelling and steering mechanism in which the propeller is rotatable about a horizontal axis for propelling the vessel and additionally angularly adjustable about a vertical axis for steering the vessel, and in which the propeller is carried by and mounted directly upon the shaft of a propeller actuating electric motor, whereby the organization, while simple in design and construction and comparatively inexpensive to manufacture, is nevertheless highly efficient in operanon.

Another principal object of the present invention is of sea water into any of the rotary parts of the turret,

all of the main rotary parts of the turret being suitably journalled within anti-friction means to insure free and easy rotation of the relatively movable parts of the turret.

Still another principal object of the present invention is to provide a compact organization which is adapted for use in small as well as large vessels to serve both as a propelling and steering mechanism, and which is designed to supply driving power to the propeller directly from an electric motor that is encased in a housing which is revoluble, for purposes of steering, about a vertical axis while the electric motor is operating to supply driving power to the propeller, the arrangement being such that the propeller shaft may be quickly rotated through an arc of 180 degrees for reversing the direction of move ment of the vessel, whereby the use of separate reversing gears is eliminated.

Other objects and advantages of the present invention will appear more fully hereinafter, it being understood that the present invention consists substantially in the combination, construction, location and relative arrangement of parts, all as described in detail hereinafter, as shown in the accompanying drawings and as finally pointed out in the appended claims.

in the accompanying drawings, which illustrate a preferred construction embodying the principles of the present invention:

Figure 1 is a vertical view, partially in cross section, of a propulsion-steering turret mounted in the hull of a vessel in accordance with the present invention;

Figure 2 is an enlarged fragmentary vertical section showing details of the means for sealing the turret receiving opening in the hull of the vessel against the entry of seawater;

Figure 3 is a horizontal view, as indicated by the line 3-3 in Figure 1;

Figure 4 is a side elevation of the electric motor housing and the propeller depending from the turret below the bottom of the vessel, as indicated by the line 44 of Figure 1, parts being broken away for the sake of clarity;

Figure 5 is a vertical view, partially in cross section, generally along the line 5--5 of Figure 4;

Figures 6 and 7 are vertical sections respectively on lines 6-6 and 7-7 of Figure 4;

Figure 8 is a horizontal view, partially in cross section, along the line 8-8 of Figure 5;

Figure 9 shows a member for retaining a sealing ring that is operative to seal the propeller shaft receiving opening in the electric motor housing;

Figure 10 is a section on line 10-10 of Figure 9;

Figure 11 is a vertical section on line 11-11 of Figure 12; and

Figure 12 is a horizontal view of the electric motor housing, partially broken away to expose its contents and cross sectioned for the sake of clarity.

In the illustrated propulsion-steering turret, constructed in accordance with and embodying the principles of the present invention, a main support 10 of generally circular, hollow form is suitably mountedin fixed position upon the hull of the vessel in the region of its stern. As most clearly appears in Figures 1, 2 and 3, this stern region of the vessel is fitted with a plurality of radially extending l-beams 11 each of a height sufiicient to fit snugly between the inner and outer hulls 12 and 13 of the vessel, the inner ends 14 of the radially extending beams each terminating near the edge of the circular opening provided in the hull bottom for mounting of the propelling and steering mechanism.

Referring particularly to Figure 2, the main support 10 is provided with a lower end portion that is enlarged in diameter and which is undercut, as at 16, to provide an annular groove'for accommodating therein an annular water sealing assembly 17 to be described hereinafter.

Extending radially outwardly from the enlarged portion of the main support 10 are a pair of vertically spaced annular flanges 18 and 19, the flange '18 being secured, as by bolts 20,- to the outer hull 13 of the vessel and the flange 19 being secured, as by studs 21, to the upper flanges 22 of the radially disposed I-beams 11. In the installation of the main support 10 within the vessel, the preferred procedure would be to lay and suitably secure the radially extending I-beams 11 i of the vessel formed by its outer hull 13 and then mount the support 10 within the hull opening located between the inner ends of the I-beams, the support 10 being then secured to thehull 13 by the bolts 20 and to the I-bearns .11 by the studs 21 so that it is strongly and adequately supported by the hull and its reinforcing I-beams 11.

Thereafter, the inner hull 12 may be laid to fully enclose the region immediately surrounding the mounted support 10.

Referring particularly to Figure l, the upper end of the vertically disposed support 10 is preferably provided with an outwardly flared annular section 23 that internally accommodates a correspondingly tapering annular roller bearing assembly 24. Formed internally of the member 10 at a point intermediate its opposite ends is an annular fiange 25 that is undercut, as at 26, to provide an annular recess for accommodating therein an annular roller bearing assembly 27, most clearly shown in Figure 2.

R-otatably supported within the stationary main supporting member 10 is a so-called turret assembly comprising an upper member 28 and a lower member 29 suitably secured together by a plurality of circumferentially spaced, bolts preferably arranged in two sets 30 and 31 concentric with respect to each, the inner set 31 of these bolts being projected through registering lugs 32 and 33 Patented May 13, was

respectively formed as integral internal elements of the turret members 28 and 29. The proximate ends of the turret members 28 and 29 abut one another along the horizontally extending median plane of the internal annular flange ,of the stationary main supporting member 10 and are externally recessed so as to conjointly form an annular groove 34 that receives the flange 25, whereby the turret assembly is secured against axial displacement.

The upper end of the vertically disposed turret member 28 is provided with an outwardly flared annular section 35 that terminates in a portion the circular outer edge of which is provided with a set of detents to form a spur gear 35' disposed for rotation in a horizontal plane. The upper turret member 28 fits snugly with-in the upper portion of the stationary support 10 and is supported for rotation therein by the roller bearing assembly 24 suitably interposed between the flaring annular sections 23 and 35 respectively of the stationary member 10 and the turret member 28.

The lower turret member 29 is nested in the lower portion of the stationary support 10, being provided with a short cylindrical thick wall portion 36 that is radially spaced inwardly from and concentric with a cylindrical wall portion 37 which depends from the stationary support 10, between the undercuts 16 and 26. The lower turret member 29 is provided with a horizontally extending bottom wall 38 bounded by an external radially extending annular flange 39 that closely underlies the cylindrical wall portion 37 of the stationary support 10 and which spans across the groove formed by the undercut 16 to abut the outer side wall of the groove, designated 40. As indicated h'ereinbefore, fitted between the concentric walls 36 and 37 respectively of the lower turret member 29 and the stationary member 10 is the annular roller bearing assembly 27 which serves conjointly with the annular roller bearing assembly 24 to provide'for easy rotation of the turret assembly within the stationary support 10.

It will be apparent, of course, that in assembling the turret for rotation within its support, the upper turret member 28 is inserted downwardly into the top portion of the support 10, while the lower turret member 29 is projected upwardly into the bottom portion of the support 10, the two members 28 and 29 being then secured together by the bolts 30 and 31. The internal flange 25 of the support 10 then functions in the nature of a key or spline to prevent axial movement of the turret assembly relative to its stationary support while permitting free rotation of the turret within the stationary support.

In order to insure against the entry of sea water into the vessel by passage between the relatively movable turret assembly and support 10 and also to protect the roller bearing 27 against sea water damage, an effective water seal is interposed between these relatively movable parts, as will now be described. As most clearly appears in Figures 1, 2 and 3, the annular flange 39 of the lower turret member 29 in effect constitutes a bottom closure member for the annular groove formed by the undercut 16 in the stationary support 10. Disposed'within this enclosed groove are a pair of sealing rings 41-42 formed of Teflon, fiber or any other material resistant to the deleterious effects of salt water, pressure and friction. These sealing rings are carried by the flange 39, the ring 41 being of a lesser diameter than the ring 42 and being disposed in concentric radially spaced relation thereto.

Likewise located within this enclosed groove is a generally flat annular pressure shoe 43 that is carried by the sealing rings 41-42, this pressure shoe being radially of such a width as to fully span the enclosed groove, and being vertically spaced from the underlying flange 39. The sealing rings 41-42 are generally rectangular in transverse cross section, their opposed circumferentially extending edges being rounded or tapered, as shown. The pressure shoe 43 is undercut, as at 44-44, to provide annular recesses for accommodating respectively the upper portions of the sealing rings 41-42, and the flange 39 is recessed, as at 45, and grooved, as at 46, for accommodating respectively the lower ends of the sealing rings 41-42. When these sealing rings are accommodated in the manner aforesaid, the inner circumferentially extending edge of the sealing ring 41 and the outer circumferentially extending edge of the sealing ring 42 are disposed respectively in abutting relation to the opposite side walls of the enclosed groove.

The annular pressure shoe 43 is designed to press the sealing rings outwardly of each other and downwardly against the flange 39 to thereby effect a water-tight seal between the stationary support 10 and the rotatable turret assembly. The necessary pressure is imposed upon the pressure shoe 43 by a plurality of circumferentially spaced pressure-applying devices 45 suitably mounted in the support 10. Each of these devices comprises a roller 46 that is engaged with an annular rib 47 formed on top of the pressure shoe 43. The roller 46 is carried by a plunger having a head 48 in which the roller 46 is mounted to revolve freely and a square shank 49 embraced by a coil compression spring 50. The assembly comprising the roller 46, roller mounting plunger 48-49, and the spring is slidably fitted in a bore 51 that extends vertically through the enlarged lower end of the support 10 and which communicates with the underlying enclosed groove containing the pressure shoe 43. The upper end of the bore 51 is closed by a member 52 that is provided with a centrally located square aperture which slidably receives the shank 49 of the plunger. The member 52 serves to keep the plunger from turning about its axis and as a seat for the coil spring 50. By employing an adequate number of the pressure devices 45 uniformly spaced circumferentially about the pressure shoe 43, effective water-tight sealing is obtained uniformly about the full circumference of the rotatable turret assembly and for all positions into which it may be rotated.

As most clearly appears in Figure 1, underlying the turret assembly is a hollow water-tight housing comprising a pair of hanger or auxiliary twin rudder sections 53-53 that depend from the lower turret member 29 and carry a horizontally disposed motor housing section, generally indicated by the numeral 54, positioned a substantial distance below the bottom of the vessel. ring particularly to Figures 4, 5 and 8, each of the hangers or auxiliary rudders 53 is a hollow flat tubular member comprising a pair of upright opposite side walls 55-56 connected together by a pair of upright side wall portions 57-58, the hanger being open at its upper and lower ends. provided with coplanar external flanges 59-59 that abut the under surface of the lower turret member 29, these flanges being provided with a plurality of apertures, as at 60, to receive a set of studs 61 that are threaded into the lower turret member 29, whereby the hangers 53-53 are secured to the latter. The lower ends of the side walls 55-55 of the hangers 53-53 are' provided with coplanar external flanges 62-62, and the lower ends of the side walls 56-56 of the hangers 53-53 are provided with depending thickened wall portions 63-63. I

Referring particularly to Figures 4 through 7, the motor housing section 54 is provided with longitudinally extending thickened wall portions 64-64 and upstanding formations 64a-64a and 64b-64b, each portion 64 and its associated portions .64a-64b being positioned to conjointly fully underlie the hanger 53 and being arranged and formed complementally to the lower end of the hanger 53 so. as to snugly receive the latter. The lower ends of the hangers 53-53 are provided with a plurality of apertures to receive sets of studs 65-6511 that are threaded into the thickened wall portions 64-64 of the motor housing section 54, whereby the motor housing section 54 is secured to the hangers 53-53.

The thickened top wall portion 6'4-64 of the motor housing section 54 are cut away, as at 66-66, so as to Refer- I The upper ends of the hangers 53-53 are' provide longitudinally extending ledges 67-67 that are located just inside the thickened wall portions 63-63 of the hanger side walls 56-56, these ledges 67-67 (see Figures 4 and 6) terminating, as at 68-69, a substantial distance short of the front and rear of the hangers 53-53, whereby vertically extending openings 70-70 are formed, these openings being respectively in communication with a pair of openings 72-72 that are formed in the upright housing portions 64a-64a and which lead into the interior of the motor housing section, and whereby vertically extending openings 71-71 are also formed, these latter openings being respectively in communication with a pair of openings 73-73 that are formed in the upright housing portions 6411-6412 and which likewise lead into the interior of the motor housing section.

The horizontally disposed motor housing section 54 comprises three members 82-83-34 (see Figures 4, 8, and 12) that are suitably fitted and secured to one another in end to end relation, as by a plurality of bolts 85-8511 to form the main body part of the section 54. The members 82-83 are provided respectively with a pair of centrally apertured opposite end walls 74-75, and extending inwardly respectively from the end walls 74-75 are a pair of coaxially alined cylindrical internal walls 76-77 the hollow interiors of which correspond in diameter to and register with the central apertures in the end walls 74-75 Intermediate the opposite end portions respectively of these cylindrical portions 76-77 are a pair of centrally apertured auxiliary walls 78-79, and extending radially outwardly respectively from the cylindrical internal walls 76-77 are a plurality of spider arms 80-81 that secure the internal walls 76-77'to the cylindrical outer walls respectively of the members 82-83.

The motor housing section 54 additionally comprises an annular motor bilge head or housing tail part 86 located immediately to the rear of the member 83. This part 86 has an axially flaring outer wall 87 and a cylindrical inner wall 88 joined together by a centrally apertured end wall 89 and a plurality of radially extending,

spider arms 90. The large diameter end of the tail part 86 is suitably fitted to the end wall 75 of the member 83 and is secured thereto by a plurality of studs 91, as shown.

Referring particularly to Figure 12, at the front end of the main body part of the motor housing section 54 is a ball bearing unit designated generally by the numeral 92, mounted in the centrally apertured auxiliary Wall portion 78, and at the rear end of the main body part of the motor housing section 54 is a roller bearing assembly,

designated generally by the numeral 93, on the outer side of the auxiliary wall 79. Extending through the main body part of the motor housing section 54 and through the motor housing tail part 86 is a propeller shaft 94 a front end portion of which is journaled in the ball bearing unit 92 and a rear end portion of which is journaled in the roller bearing assembly 93, whereby the pro peller shaft is mounted to rotate freely about its axis. For securing the propeller shaft 94 against axial displacement, on each side of the auxiliary wall 78, is a tapered roller bearing unit, designated generally by the numeral 95, which bearing has associated therewith a suitable annular thrust collar 96. The front end portion of the propeller shaft 94 is reduced in diameter to provide an annular thrust transmitting shoulder 97 that abuts the inner thrust collar 96' and is fitted with a pair of thrust transmitting nuts 98-98 that abut the outer thrust collar 96.

Immediately in advance of the member 82 of the motor t3 fitted with a suitable sealing plate 101 that is secured thereto by a plurality of studs 102, as shown.

It will be understood that in effecting the connections between the turret assembly and the underlying housing and between the several parts of the latter that are de tachably secured together in the manner aforesaid, suitable gaskets (not shown) are employed in order to make the construction water-tight. Referring particularlyto Figure 12, for effectively sealing the propeller end of the shaft 94 against the entry of sea water, a sealing ring retainer in suitable fitted between the member 83 and the motor housing tail part 86. This retainer is in the form of a centrally apertured plate 103 that suitably receives and retains an inner sealing ring 104 which sealingly embraces the propeller shaft 94. Atthe opposite end of the tail part 86 is a second sealing ring retainer in the form of an annular centrally apertured member 105. This member is provided with an annular external flange 1.06 that is fitted to the end Wall 89 of the tail part 36, the flange being provided with a plurality of apertures, as at 107, to receive a set of studs 108 that are threaded into the tail part 86, and is internally grooved to receive and retain an outer sealing ring 109 that sealingly embraces the propeller shaft 94. Between the retainer members 103 and is an assembly of four complementally axially tapered sealing rings 110, 111, 112 and 113 nested together against the retainer member 105 and held thereagainst by a coil compression spring 114 that embraces the shaft 94 and which is seated against the retainer member 103. The sealing rings 104 and 109 through 113 are formed of Teflon, fiber or any other material resistant to the deterious effects of salt water. posed upon the sealing rings 110, 111, 112' and 113 by the coil spring 114 is sufiicient to press these sealing rings into sealing contact with one'another and additionally by wedging action, to slightly contract the sealing rings and 112 into sealing contact with the shaft 94 and to slightly expand the sealing rings 111 and 113 into sealing contact with the inner wall 88 of the housing nose part 86. In this connection, a slight amount of seepage of sea water into the housing tail part 86 is desirable for purposes of lubrication, this seepage being evacuated from the interior of the housing tail part 86 in a manner to be described. A propeller 115 is removably fitted on the freely projecting end of the shaft 94 in any suitable manner.

Referring particularly to Figures 7 and 12, within the intermediate member 84 of the main body part of the motor housing section 54 is an electric motor rotor element 116 that is carried by the propeller shaft 94 and which is mounted for rotation with the latter. The rotor element 116 includes a suitable hub 117 that extendsrearwardly freely into the internal wall 77 of the main body part end member 83 and which is insulated from the shaft 94 by a sleeve 118 formed of suitable material.

rotor element 116, in operative association with the lat-l ter, is an electric motor stator element 122, from which: conductor Wire leads, designated 123, extend upwardly on one side and interiorly of the water-tight housing, being passed through the communicating openings 73-71 and the hollow interior of the hanger section 53. These. leads 121-123 continue upwardly into the hollow inte-.

rior of the turret assembly, being passed respectively through openings 124-124 that are formed in the lower The pressure imturret member'bottom wall 38 and which register respectively with the hollow interiors of the hanger sections 53-53.

Referring particularly to Figures 1 and 3, the several leads l21-123 are operatively connected respectively to an assembly of concentric radially spacedconductor rings, designated generally by the numeral 125, that are suitably mounted upon the top of a horizontally extending annular member 126 which is formed of insulating material. The member 126 is conveniently mounted for rotation with the turret assembly by suitably fitting the same over the reduced diameter upper end portion of a hollow cylindrical post 127 that is centrally located within the turret assembly and which is rigidly secured to the lower turret member bottom wall 38.

Overlying the annular member 126 is a second annular member 128 that is formed of insulating material and which mounts an assembly of brushes depending from the under surface thereof, designated generally by the numeral 129, and operatively engaged respectively with the conductor rings of the assembly 125. This member 128 is stationarily mounted conveniently by suitably fitting and securing the same, as by a plurality of studs 130, to a horizontally extendnig cover plate 131 for the turret assembly, this cover plate being secured to the upper turret member 28, as by a plurality of studs 132. Thus, the leads 121 are operatively connected respectively through certain conductor rings 125 and brushes 129 to conductor wire leads designated 133, while the leads 123 are operatively connected respectively through certain other conductor rings 125 and brushes 129 to conductor wire leads designated 134. The leads 133 are operatively associated with a suitable electric power source for energizing the electric motor comprising the electric rotor element 116 and the stator element 122, whereby the propeller shaft 94 and the propeller 115 that is mounted thereon are actuated. These leads are likewise operatively associated with suitable switching gear 135 for reversal of operation. The leads 123 are associated with a resistor unit 136 for controlling speed of operation.

For lubrication of the propeller shaft bearings, a pair of tubular lines 139139 are suitably connected to the base portions of the post 127 and extend downwardly through the water-tight housing to selected points, as at 140141, these lines being routed through the hollow interiors of the hanger sections 5353 and the communicating passages 70- 72 and 7173. If desired, portions of these lines 139-139 and/or of the conductor wire leads 121-123 may run over the ledges 6767 along the top of the motor housing main body part. A suction line 142 havinga suitable 'rotojoint 142a extends downwardly through the post member 127, and branches thereof, designated"143143, extend laterally through the wall of the post member 127 and downwardly to selected points, as at 14-1145, these branches being routed in generally the same manner as the oil lines l'39--139. The interior of the base portion of the post member 127 serves asa reservoir for oil, which is conducted through the lines 139-139 to selected parts in need of lubrication, and undesirable accumulations of spent oil in the motor housing are evacuated by suction induced by means (not shown) suitably connected with the upper end of the suction line 142. In this connection, oil is supplied to the bearings at the front end of the propeller shaft through the oil line 140, from whence it is evacuated through the suction line 144. In addition, oil is supplied to the bearing at the rear end of the propeller shaft through the oil line 141. Any excess oil spills into the housing tail part 86 through a suitable aperture (not shown) in the retainer member 103, from which it is evacuated, together with any sea water seepage, through the suction line 145.

To efiect disassembly of the propeller shaft organization for purposes of service, maintenance and repair,

8 the motor housing nose part 99 is removed so as to expose the thrust nuts 98-98 that'are threaded on the end of the propeller shaft 94. After removing the nuts 9898 from the shaft 94, the end member 82 of the motor housing main body part is removed. Now the propeller is removed from the shaft 94, whereupon the assembled shaft 94 and electric motor rotor element 116 are removed as a unit by drawing the shaft 94 forwardly soas to slip the propeller end thereof through the end member 83 of the motor housing main body part.

Rotation of the turret assembly and of the propeller assembly as a unitary organization for purposes of steering the vessel is effected by means of a power driven pinion 146 in mesh with the turret gear 35. The pinion 146 is revolubly mounted upon an axially fixed shaft 147 and is preferably driven by a reversible electric motor 148 through a suitable speed reduction unit 149 of the worm gear type. For emergency use, as upon failure of electric power to the motor 148, an auxiliary driving mechanism may be provided for manual operation of the steering turret, which auxiliary steering mechanism may include a hand wheel operated bevel gear set 150 that is operatively associated with the pinion 146 and which is adapted to be thrown into and out of operation by any suitable clutch mechanism, not shown in detail.

It will be understood, of course, that the present invention is susceptible of various changes and modifications which may be made from time to time wthout departing from the general principles or real spirit of the invention, and it is accordingly intended to claim the same broadly, as well as specifically as indicated in the appended claims.

What is claimed as new and useful is:

1. In a marine propelling and steering mechanism, in combination, a hollow main support fixedly mounted above an opening in the hull of a vessel, a hollow turret assembly revolubly nested within and fixed against axial displacement relative to said support, a water-tight housing depending from said turret and arranged beneath the opening in said hull for rotation with said turret, a shaft revolubly journaled in and fixed against axial displacement relative to said housing, a propeller mounted upon a terminal portion of said shaft extending through the wall of said housing, electric motor elements within said housing operatively associated with said shaft,

J. and means for supplying said motor elements with electric current for actuating the same and thereby turning said shaft and propeller, said supply means including stationary brush means carried by said main support and mounted over the hollow interior of said turret, and conductor ring means carried by said turret and mounted therein for rotation with said turret in contact with said brushes.

2. In a marine propelling and steering mechanism as defined in claim 1 wherein the conductor ring means is mounted upon a hollow upright central post within said turret mounted for rotation with the latter, the lower end of said post being closed for use of the interior of the post as an oil reservoir.

3. In a marine propelling and steering mechanism as defined in claim 2 wherein a system of oil lines extend from the interior of said post to the interior of said housing and to selected points of lubrication within the latter.

4. In a marine propelling and steering mechanism as defined in claim 3 wherein a suction line extends centrally through the hollow interior of said post and branches off to selected locations within said housing for withdrawing spent oil therefrom, said system of suction lines being mounted for rotation with said turret.

5. In a marine propelling and steering mechanism, in combination, a hollow main support fixedly mounted above an opening in the hull of a vessel, a hollow turret assembly revolubly nested within and fixed against axial displacement relative to said support, a water-tight housing depending from said turret and positioned beneath the opening in said hull and rotatable with said turret including a main body part having a pair of cylindrical walls extending inwardly toward one another respectively from opposite ends of said main body part, closure means for said cylindrical walls conjointly forming therewith a pair of enclosures, a bilge head extending rearwardly from said main body part and provided internally with a cylindrical wall, anti-friction bearing means respectively housed in said enclosures, a shaft extending into said housing through said bilge head and having longitudinally spaced portions respectively journalled in said anti-friction bearing means, a propeller mounted upon a terminal portion of said shaft, means within the cylindrical wall of said bilge head for sealing the bilge head against entry of water, and vacuum inducing means extending through said main body part and into said bilge head for evacuating any water that might accumulate therein.

6. In a marine propelling and steering mechanism as defined in claim 5 wherein the interior of the bilge head communicates with the adjacent one of the bearing enclosures, said enclosures communicate with a source of oil for lubricating said bearings, and said vacuum inducing means extends into the other one of the bearing enclosures and is operative to evacuate water and oil accummulations from said enclosures and bilge and to induce circulation of air.

7. In a marine propelling and steering mechanism as defined in claim 5 wherein the bilge head sealing means comprises an assembly of complementally axially tapered flexible sealing rings axially spring pressed to wedgingly contract certain of said rings and expand others, whereby the former closely embrace the propeller shaft and the later firmly engage the cylindrical bilge head wall.

8. In a marine propelling and steering mechanism as defined in claim 5 wherein closure members are provided respectively at opposite ends of the cylindrical bilge head wall for conjointly forming therewith the enclosure for the bilge head sealing means, and said members are fitted respectively with additional sealing rings closely embracing the propeller shaft, said members being operative to furnish seats respectively for said assembly of flexible rings and the spring means for axially compressing the same.

References Cited in the file of this patent UNITED STATES PATENTS

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