Патент USA US2111325код для вставки
March 15, 1938., ‘ ‘ o. c. LINTHWAITE " OUTBOARD v 2,111,325 MOTOR _ Filed June 4, _l935 2 Sheets-Sheet ,1 D } mmvron; OWEN MC. Lmmwmr" BY ATTORNEY V March 15, 1938- ‘ _ 0. c. LINTHWAITE 2,111,325 OUTBOARD MOTOR Filed June 4, 1955 2 ‘Sheets-Sheet 2 INVENTOR. ' Oman ‘C. Lmmwanr BY _ ATTORNEY 2,111,325 Patented Mar. 15, 1938 UNITED STATES PATENT OFFICE 2,111,325 ' ' 1 OUTBOARD MOTOR Owen o. Lin’thwaite, South Bend, Ind., assignor to Bendix Products Corporation, South Bend, Ind., a corporation of Indiana , Application June 4, 1935, Serial No. 24.898 6 Claims. (Cl. 115-17) Figure 5 is a view similar to Figure 2, showing a This invention relates to outboard motors ‘for the propulsion of watercraft, and more particu modi?ed form of the invention; Figure 6 is an end elevation of Figure 5; larly to‘ a novel streamlined lower unit therefor. In the operation of outboard motors, it has 5 been found dif?cult to provide suitable means for disposing of the exhaust gases from the engine in such a manner as to avoid noise without un necessarily adding to the weight by employing ‘a conventional type muffler as ordinarily used in lo connection with internal combustion engines in Figure '7 is a view on' the line 1-1 of Figure 5; Figure 8 is a view similar to Figure 2,‘showlng 5 a further modi?cation of the invention; Figure 9 is an end elevation of Figure 8; Figure 10 is a view on the line Ill-l0 of Fig ure 8; 1 It has also been found that to obtain maximum efficiency from a propeller, means must be pro Figure 11 is a view similar to Figure 2, show- 10 ing a further, modi?cation of the invention; Figure 12 is an end elevation of Figure 11; Figure 13 is a view on the line l3-l3 of Figure vided to’ prevent the propeller from cavitating 11; and other arts. . 15 due to a depression in the ?uid immediately ad Figure 14 is a view similar to Figure-2, show- 15 _ jacent and following ' the power transmitting housing, In the past this difficulty has ' been ing' a still further modi?cation of the invention. Referring more particularly to Figure 1, there avoided by positioning a ?at anticavitation plate to overlie the propeller and to avoid the forma 20 'tion of a depression in the ?uid adjacent the pro is shown an outboard motor assembly including peller. , an internal combustion engine‘ provided with a stream-lined hood 20, an upper housing section 20 22, and a lower stream-lined housing section 24. An. object of this invention is therefore to‘ pro vicle a novel stream-lined lower unit wherein an expansion chamber for exhaust gases is provided, 25 and means are employed to discharge the exhaust adapted to‘be ?xed to the transom 25 of aboat by means of an adjustable clamp 28, A lever 30, gases below the surfaceof the water at such an tion 22, is provided to turn the outboard motor The outboard motor assembly thus formed is > operably connected with the upper housing sec- 25, angle with respect to the propeller as to avoid in--v assembly about arpivot point to effect‘ steering terference with the successful operation "of the " operations'of the boat.v Fuel is supplied for the operation of the engine from a fuel tank 32 posi-' propeller. ' 30v 30 Another object of the-invention 15.110. provide'a' -tioned below thefstream-lined hood 20. . The upper housing'section .22 is'formed‘with. stream-lined lower unit-for an outboard motor so ‘designed that‘ it maybe formed‘by'ai'die-casting _ two longitudinal passages‘ 34 and 3G. ‘The lower ' operation‘. . . . . . ' Another object of_the'invention.is to- provide 35 means for quietly ‘and e?ic'iently disposing of the exhaust gases of anoutboard motor so as to avoid back pressure on the engine and ‘to minimize the‘ energy required to discharge the gases. ‘ Other objects and advantages of the present 40 invention will appear in the following detailed de scription, taken in connection with the accom panying drawings, submitted‘ for purposes of i1 lustration only, and not intended to de?ne the scope of the invention, reference being had for 45 that purpose to the subjoined claims. 'In the drawings,‘ wherein similar reference characters refer to similar parts throughout the several views: , ' _ housing. section'24;is‘formed with two longitudif 'nal passages 38 and “separated by a partition, wall 42 which adds stiffness and strength'to the 35 lower housing 24. , _ ' v The lower housing section 24 is provided with - a propeller shaft housing 44, and a propeller pro tecting fln 46 designed to travel ahead of the pro peller‘ 48 to prevent the propeller 48 from strik- 40 ing an object which would damage the propeller. An anti-cavitation plate 50 is provided to over lie the propeller 48 to prevent the formation of a depression in the fluid, adjacent and following the lower housing section 24, and to prevent the 45 formation of air pockets in fluid through which the propeller is passing. A stream-lined ?n 5|, - to facilitate steering operations, is carried by the lower housing 24 immediately above the anti 50‘ motor clamped to the transom of a boat; > , vcavitation plate 50, as shown. 50 Power from the engine is transmitted to the Figure 2 is an elevational view, partly in ‘sec-1 tiongon an enlarged scale, of the lower portion propeller 48 through an engine drive shaft 52 ex 1f 1 Figure 1 is a view in elevation of an outboard of Figure 1; 55 ; , Figure 3 .is an end elevation of Figure 2; Figure 4 is a view on the line 4--4 of Figure 2; tending through the longitudinal passages 34 and 38 respectively of the upper and lower housing sections 22 and 24. ' 55 2 2,111,825 Exhaust gases from the engine are conducted from the engine to the longitudinal passage 36 in the upper housing 22 through a connection 81 interposed between the exhaust port oi’ the engine and the upper section of the housing 22. The longitudinal passage 36 is of progressively increasing cross sectional area downwardly, and communicates with the longitudinal passage 40 formed in the lower section 24. The longitudinal 10 passage 40 provides a convenient expansion chamber for the exhaust gases to prevent back pressure on the engine cylinder. The exhaust gases are cooled as they travel downwardly through the longitudinal ‘passages 36 and 40. 15 The normal water level through which the lower unit 24 is passing is above the stream-lined ?n 5| so that a chilling effect of the exhaust gases takes place to contract the ‘gases. The volume of the gases is therefore _decreased and vback 20 pressure is reduced to a minimum. The gases are discharged beneath the lower surface of the anti-cavitation plate 50 and above the propeller 48 through a rearwardly extending aperture 54, having a downwardly projecting lip 56. The lip 25 56 operates to form a section of reduced ?uid preferably positioned forwardly of the trailing edge of the anti-cavitation plate ill as clearly shown in Figure 10. Figures 11, 12, and 13 illustrate a further modi ?ed form of the invention wherein a stream-lined section III is formed by extending a portion of the housing 24 below the anti-cavitation plate 50. The stream-lined section 80 is provided with an exhaust discharge opening 82 projecting be~ low the anti-cavitation plate 50 and reinforced by a ?n 84 projecting between the stream-lined section 80 and the anti-cavitation plate 50. In this embodiment, the exhaust gases are dis charged below the anti-cavitation plate. It has been found by experiment that the arrangement 15 shown herein will not cause the propeller 48 to cavitate. Figure 14 shows a further modi?ed form or the invention wherein the lower section 24 is cast or otherwise formed integral with the anti-cavi 20 tation plate 50, as in the other modi?cations pre viously discussed. The stream-lined ?n and the exhaust outlet are not cast integral therewith, however, but are formed by a stamping 90 adapt ed to be ?xed to the lower unit by any suitable 25 pressures to the rear of the opening 54 thereby means such as a bolt 92 engaging a boss 94 to facilitating the ?ow of the exhaust gases from securely hold the stream-lined ?n 90, and the the passage 40 as the lower housing section 24 ' exhaust passageway securely tothe lower hous ing section 24. In this embodiment of the in moves through the water. vention the casting of the lower unit 24 is much 30 It has been found from experiment that ex 30 haust gases discharged above the propeller, but ‘ simpler in view of the fact that the stream below the anti-cavitation plate in the manner described above will not cause the propeller to cavitate, and will not subject the engine to back 35 pressure. lined ?n and the exhaust opening are not cast integral with the housing 24; This application is a continuation-in-part of my co-pending application Serial No. 2,085, filed ‘ In operation when the engine is running, the January 16, 1935. While several illustrative embodiments of the exhaust gases are discharged from the engine through the connector 31 to the passage 36 of invention have been illustrated and described, it the upper housing section 22, communicating is not my intention to limit the scope of the in with the passage 40 of the lower housing 24. The vention to the embodiments shown nor other 40 wise than by the terms of the following claims. exhaust gases pass ‘through a passageway of pro gressively increasing cross sectional area, and are subjected to a progressively decreasing tem perature, causing them to contract as they movev 45 downwardly, heat being conducted through the walls of the housing 24 to the water through which it is passing. The gases are drawn out through the opening 54, extending through the anti-cavitation plate 50 because of the move 50 ment of the ?uid over the downwardly projecting lip 56. Figures 5, 6, and 7 illustrate a modi?ed form of the invention wherein the anti-cavitation plate 50 has a ?at lower surface designed to overlie the propeller 48. The exhaust gases are discharged from the passageway 40 through an opening 60, formed by an expansion of the ?n 5| to form the rectangular shaped opening 60 above the anti-cavitation plate 50. The opening 60 is po 60 sitioned to discharge the exhaust gases at a point intermediate the trailing edge of the anti-cavi tation plate 50, and the forward edge thereof. This embodiment of the invention is more par ticularly described in my copending application, 65 Serial No. 2,085, ?led January 16, 1935. Figures 8, 9,\and 10 illustrate an embodiment of the invention wherein a rectangular housing I claim: 1. In an outboard motor, a hollow housing, an anti-cavitation plate, a stream~1ined ?n ?xed to the housing and connected with the anti-cavita tion plate by a reinforcing web extending from the mid-section of the ?n to the plate, and-a rearwardly directed opening of rectangular ‘cross section in the central portion of the trailing edge of the ?n anterior to the trailing edge of the anti 50 cavitation plate and above said plate. 2. In an outboard motor, an internal combus tion engine, a propeller to drivethe motor, a hollow stream-lined housing extending between the engine and‘the propeller, means to conduct exhaust gases from the engine to the housing, an anti-cavitation plate carried by the housing and positioned to. overlie the propeller, a portion of the housing being shaped to form a stream— lined ?n extending between the housing and the 60 plate, the lower portion‘ of the ?n being extended laterally to form a single rectangular shaped rearwardly directed opening above the anti cavitation plate to permit the escape of exhaust gases from the housing, and a reinforcing web 65 extending longitudinally between the lower por tion of the ?n and the upper portion of the anti ‘III is formed above the anti-cavitation, plate 50, and is supported by a ?n ‘l2 projecting from the housing ‘III to the anti-cavitation plate 50. The housing 10 is stream-lined. into the ?n 5| cavitation plate. and forms an exhaust discharge opening 14 com the engine and the propeller, means to conduct 3. In an outboard motor, an internal combus tion engine, a propeller to drive the motor, a hollow stream-lined housing extending between municating with the longitudinal passageway 40, exhaust gases from the engine to the housing, formed in the lower housing section 24. In this and an anti-cavitation plate carried by the hous ing and positioned to overlie the propeller, a por embodiment of the invention the housing 10' is 75 2,111,325 tion of the housing ‘being shaped to form a stream-lined ?n extending between the housing and the plate, the lower portion of the ?n being extended laterally to form a single rectangular shaped rearwardly disposed opening in the central portion of the ?n discharging at a point interme diate the extreme ends of, the anti-cavitation plate and slightly above said plate to permit the escape of exhaust gases from the housing at a point below the surface of the ‘water. 4. In an outboard motor, an internal combus tion engine, a. propeller, a single hollow housing including two separate chambers extending be tween the engine and the propeller, means to con 15 duct exhaust gases from the engine to one of the chambers of the housing, a drive shaft in the other of said chambers, an anti-cavitation plate carried ».by the ‘housing and positioned to overlie the propeller, a portion of the housing being shaped to form a stream-lined ?n extending to the anti-cavitation plate,v the central portion of the ?n being extended laterally to form a single rectangular shaped rearwardly directed opening bounded by four walls separate and independent 25 from the upper surface of the anti-cavitation plate, and reinforcing means betweenthe ?n and l the anti-cavitation plate. I 3 5. In an outboard motor, a combustion'engine, a propeller, a housing extending between en gine and the propeller; means to direct exhaust gases from the engine to the housing,‘ an anti cavitation plate carried by the housing, and ex haust outlet means including an expanded ?n connected to the housing andextending longitu dinally above the anti-cavitation plate and con nected thereto by a reinforcing web to discharge exhaust gases from the housing at a point above 10 the anti-cavitation plate but below the normal water level. 6. In an outboard motor, an ‘internal combus tion engine, a water propeller, a housing extend ing between the engine and the propeller, means to conduct exhaust gases from the engine to the housing, an anti-cavitation plate carried by the housing, and means comprising a stream-lined ?n including a rearw‘ardly directed exhaust out- ' let supported by the housing above the plate, a reinforcing web between the fin and, the anti cavitation plate to support the ?n to discharge exhaust gases from the housing below the normal water level but above the anti-cavitation plate.‘ OWENv C. LINTHWAITE.