US3195521A

US3195521A - Engine

Info

Publication number: US3195521A
Application number: US328813A
Authority: US
Inventors: Robert T Larsen
Original assignee: Outboard Marine Corp
Current assignee: Outboard Marine Corp
Priority date: 1963-12-09
Filing date: 1963-12-09
Publication date: 1965-07-20
Anticipated expiration: 1982-07-20

Description

July-2o, 1965 R. T. LARSEN 3,195,521

ENGINE Filed Deo. 9, 1963 2 Sheets-Sheet 2 if; f2s/ 56,5, /2 f4 l fzf if Il [I6/IVE 27/ 242 INVENTOR.

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United States Patent O 3,I95,521 ENGINE Robert T. Larsen, Iena-mener: Failsgwis., assigner to @utbcard Marine Corporation, Waukegan, Ill., a corporation of Delaware Fiied Dec. 9, i963, Ser. No. 328,3?13 9 Claims. (CI. 12S-41.47)

The invention relates generally to marine propulsion devices, such as outboard motors.

The invention provides a sound isolating barrier between the power head and the lower unit or strut. The barrier comprises a pair of mounting plates adapted to be respectively secured to the head and to the lower unit, and a sheet of resilient material, such as rubber, which is bonded to and between said plates throughout substantially the entire area thereof. Connection of the power head and lower unit to the plates therefore results in a unitary assembly including a layer or barrier of resilient material which excludes sound and also serves to dampen vibration.

In the preferred construction, the barrier includes means affording communication between an engine exhaust gas discharge port and an exhaust gas passage in the lower unit, together with means affording communication between a water pump in the lower unit and an engine cooling jacket. Preferably, passage of coolant water through the barrier is arranged to effect cooling of the barrier, and particularly, cooling of the resilient material in the area surrounding the iiow of exhaust gas. The barrier also includes an aperture or bore for the passage of the engine crankshaft or the lower unit driveshaft to facilitate their driving connection.

Other objects and advantages of the invention will become known by reference to the following description and accompanying drawings in which FIGURE l is a partially broken away and sectioned view of an outboard motor embodying various of the features of the invention;

FIGURE 2 is an enlarged view, partially in section, of a portion of the outboard motor shown in FIGURE l;

FIGURE 3 is a sectional View taken along line 3 3 of FIGURE 2;

FIGURE 4 is an enlarged fragmentary sectional view taken along line 4 4 of FIGURE 3;

FIGURE 5 is a View similar to FIGURE 2 showing a modified construction;

FIGURE 6 is a sectional view taken along line d-e of FIGURE 5;

FIGURE 7 is a view similar to FIGURE 5 showing another modied construction;

FIGURE 8 is a fragmentary sectional view taken along line S-8 of FIGURE 7;

FIGURE 9 is a fragmentary sectional view taken along line 9-9 of FIGURE 7; i

FIGURE l0 is a fragmentary sectional view taken along line IIL-I0 of FIGURE 7;

FIGURE 11 is a view similar to FIGURES 3 and 5 showing another modified construction; and

FIGURE l2 is a sectional view taken along line IZ-IZ of FIGURE ll.

Shown in FIGURE l is an outboard motor II of generally conventional construction except that the power head 13 is connected to the lower unit I5 to form a unitary propulsion unit by a sound isolating barrier 17 inrice terposed between the power head and the lower unit. As is common practice, the power head I3 includes an internal combustion engine I9 having a crankshaft 21, a coolant jacket 23, and an exhaust gas discharge port 25.

The iower unit I5 is constructed with an exhaust gas discharge passage or conduit 27, and mounts a driveshaft 29 which is drivingly connected to a propeller 31 and which is also drivingly connected to the engine crankshaft 2l. In addition, the lower unit 15 supports a water pump 33 which is driven by the driveshaft 29 and which communicates with the engine water jacket 23 by means not shown in FIGURES l through 4.

The assemblage of the lower unit I5 and the power head I3 is supported by vibration and sound damping mountings in a shroud .35 including an engine cover 37, as disclosed in the Watkins Patent No. 3,002,489. The shroud 35 is pivotally mounted on a swivel bracket 39 which, in turn, is supported by a transom bracket 4I adapted to be mounted on the transom 43 of a boat. The power head and lower unit therefore vibrate independently of and within the shroud 35.

If desired, the motor cover can be directly connected with the assemblage of the power head and lower unit, which assemblage can be supported from a transom bracket by vibration and sound damping mountings as disclosed in the Irgens Patent No. 2,740,368. However, in order to take advantage of the present invention, it is desirable to connect the engine cover to the lower unit independently of any rigid connection with the power head.

The barrier I7 serves to at least partially exclude the transmission of sound from the power head 13 to the lower unit I5, to assist in damping vibrations set up in the power head 13, and to connect the power head 13 and the lower unit I5. The barrier I7 comprises a sheet 45 of resilient material which is interposed between and bonded to a pair of mounting plates 47 and 49. The mounting plate t7 is bolted or otherwise secured to the power head 13 while the other mounting plate 49 is bolted or otherwise secured to the lower unit l5. The sheet 45 extends generally continuously between the mounting plates 47 and 49 and can be fabricated of resilient material such as rubber.

The barrier I7 also includes provision for affording communication between the exhaust gas discharge port Z5 of the engine and the exhaust gas passage 27 in the lower unit I5. In the illustrated construction, such means takes the form of an aperture 51 extending through the barrier, and an exhaust port sleeve 53 which extends from the engine I9 through the aperture 5l and to the exhaust gas passage 27 in the lower unit I5. It is. to be noted that the portion of the aperture 51 extending through the lower mounting plate 4:9 is free of direct contact with the sleeve 53 and with the engine 19 as a whole.

Preferably, the portion of the barrier surrounding the exhaust gas aperture 5I is cooled to prevent deterioration of the resilient material and to otherwise reduce the temperature in this area. In the embodiment shown in FIGURES 1, 2, and 3, the sheet 45 an-d the adjacent faces of the mounting plates 47 and 49 are formed to provide a conduit means including a circular passage 55 generally surrounding the exhaust aperture 5I. At its ends, the passage 55 communicates with respective bores 57 and 59 extending through the lower mounting plate 49. The

, 3 i bore 57 communicates through rconduit 61 with the discharge port of the water pump 33 while the bore 59 communicates through a conduit 63 which empties into the exhaust gas passage 27. Thus, during engine operation, the portion of the barrier 17 around the exhaust gas aperture 51 is continuously cooled.

In addition to the provision for exhaust gas flow, the barrier 17 also includes another aperture 65 for passage of the crankshaft 21 or of the driveshait 29 to permit their interconnectionin driving engagement. In the construction shown in the drawings, the driveshatt 29`extends through the aperture'd without contacting theY barrier 17 and Vis splined tothe crankshaft at a point above the barrier.

When the power head is adapted to be water cooled, provision is also made for. the passage of coolant through the barrier. In the embodiment shown in FIGURE 2, separate bores (not shown) are provided for passing 'supply and discharge coolant'water through the-barrier. Such coolant flow is preferably employed to cool the portion of the barrier 17 Vsurrounding the exhaust gas aperture 51. Thus, in the embodiment shown in FIGURE 5, the vconduit 161 carrying the discharge from the water pump 133' communicates with a bore 157 extending through the lower mounting plate 149. In turn, the bore 157 communicates with one end of a circularly extending recessed passage 155 similar to ythe passage 55. At its other end, the passage 155 is connected with abore 15? which extends through the upper mounting plate 147fand which is in communication with'the coolingl jacket 123 of the engine 119. l

Discharge tlow from the engine cooling jacket 123 passies through a bore 169 extending through the barrier 117 and communicating with a'conduit 163 which, inthe case of a bypass cooling system, discharges into the exhaust gas passage 127 or, inthe case of a recirculating system, discharges into 'a supplyy port in the waterpump 133.' In some recirculating systems, the .thermostat `controlling'coolant recirculation'i's located in the power head. Under these circumstances, another borej(not shown)`can beV provided through the barrier; Y j

- In the embodiment shown in FIGURE 7, a pair of circularly extendingpassages '255e and 2551i, Ylocated respectivelyY inthe mounting plates 247. and 249, are

connected in series to cool the kbarrier'2il7 in thev area of the exhaust gas aperture 251.Y Specically, the conduit 261 extending from the water pump discharge communicates with a'bore 257 extending thnough the mounting plate 249, which bore is connected to one end of the passage 255b surrounding the exhaust Agas aperture 251; y

In the embodiment shown inYFIGURE ll, both vthey ycoolant flow to the water jacket V323 and the discharge flow from the water jacket are employedto cool the barrier 317 in the area'of the exhaust gas'dischargeKV flow..

Specitically, the conduit slwextending from the water pump discharge communicates, through `a bore 357g Vin the mounting plate 345i,k with one end of an Aarcuately shaped passage 355a whichhextends partiallyrarounid the exhaust gas aperture351. At its other end, the passage 355a communicates with a bore 357b through the upper 347 and communicates with one end of an arcuate passage 355b in the barrier, which passage also extends partially around the exhaust gas aperture. Atv its other end,

' the passage 3551: communicates with a bore 35951 which extends through the lower mounting plate 349 Vand which j is in communication with a conduit 363 connected with a discharge outlet or with a supply port on the water pump, as desired.

As seen in FIGURE 12, the arcuate passages 35551 and 355b substantially completely surround the exhaust gas aperture 351. As in the other embodiments, an additional 1.' An outboard motor including a power head, a' lower unit, and means lconnecting said power head and said lowerunit including a -pair of mounting lplates and a resilient sheet bonded to and between said plates, one

of said plates being connected to said power head and the other of said plates being connected to said lower unit.

2. An outboard motor including a power head including an internal combustion'en'g'ine having an exhaust gas discharge port, and a coolantwater jacket, 'a' lower unit including a water pump, and an exhaust gas passage, and barrier means connecting said power head and said lower unitand including a pair of mounting plates and a resilient sheet bonded to and between-said plates, one of said plates being connected to Vsaid power head and the other Vof said plates being connected to vsaid lower'unit, said barrier means also including means affording communication through said barrier meansbetween saidV exhaust gas passageand said exhaust gas discharge port, and means Y adording communication through said ybarrier means between said water pump and lsaid Water coolant jacket.

3;"An. outboard motor in accordance-with claim 2 wherein said means affording Acommunication between said water pump and said coolant jacket includes conduit meansk extending through said barrier means in the area adjacent to saidmeans affording` communication between said exhaust gaspassage and said exhaust gas discharge port. Y

4. An outboard motor' in' accordance with claim3 y wherein'said conduit means extendsfsubstantially commounting plate 347.. In turn, the bore 357i; communi- Y cates with the engine water jacket 323. .Discharge from the engine water jacket. 323 is carried by another bore l359]: which extends through the upper mounting plate pletely k:around saidmeans affording communication bel-V tweensaid exhaust gas passage and said exhaust gas discharge port. Y 5. An outboard motor in accordance with claim 4 wherein said conduit means includes a passage located Y.at-least partially in said resilient/sheet and at least partially encircling said means affording communication Vbetween said exhaust gas passage and.` said exhaust-gas discharge port. f 6. An outboard'motor in `accordance with claim 4 wherein said conduit means includes passages located entirely in saidV mounting platesjand at least partially encircling'said means affording communication between said exhaust gas passage and said exhaust gas discharge port. '7. An`outboard motorl in accordance with claim 3 wherein said conduit means Aincludes' a rst passage' at least partially encircling said means affording 'communication between said Vexhaust gasV passage and'said exhaust gas discharge porttor supplyingcoolant Vto said engine jacket, andV arsecond, passage atleast partially encircling said meansaffording communication between said exhaust gas passage and said exhaust gas discharge port for discharging coolant fromsaidjengine jacket.V

Vsages each `substantially. encircling saidiv means affording 5 6 communcaton between said exhaust gas passage and References Cited by the Examiner sald exhaust gas dlscharge port. 1 t UNITED ST AT1-S PATENTS 9. An outboard motor 1n accomance wlth clmm l 2772 6(19 17/5, G nshem 115 17 he e* wh n a' 1 *O e @I W 1' 1n sald means after 11g coumuruc non between 8901674 6/59 Rose 115 18 said exhaust gas passage and said exhaust gas discharge 5 o 1 port comprises an aperture in said barrier means and said Klehaefer 12?195 X ,L l Mohr s 11S-17 engme mcludes an exhaust gas dlscnarge tube extendmg v through said aperture free of Contact with said other RlCHARD B- WILKNSON, Pllmay Exammeplate. V; KARL J. ALBRECHT, Examiner.

Claims

2. AN OUTBOARD MOTOR INCLUDING A POWER HEAD INCLUDING AN INTERNAL COMBUSTION ENGINE HAVING AN EXHAUST GAS DISCHARGE PORT, AND A COOLANT WATER JACKET, A LOWER UNIT INCLUDING A WATER PUMP, AND AN EXHAUST GAS PASSAGE, AND BARRIER MEANS CONNECTING SAID POWER HEAD AND SAID LOWER UNIT AND INCLUDING A PAIR OF MOUNTING PLATES AND A RESILIENT SHEET BONDED TO AND BETWEEN SAID PLATES, ONE OF SAID PLATES BEING CONNECTED TO SAID POWER HEAD AND THE OTHER OF SAID PLATES BEING CONNECTED TO SAID LOWER UNIT, SAID BARRIER MEANS ALSO INCLUDING MEANS AFFORDING COMMUNICATION THROUGH SAID BARRIER MEANS BETWEEN SAID EXHAUST GAS PASSAGE AND SAID EXHAUST GAS DISCHARGE PORT, AND MEANS AFFORDING COMMUNICATION THROUGH SAID BARRIER MEANS BETWEEN SAID WATER PUMP AND SAID WATER COOLANT JACKET.