Two speed transmission with reverse for a watercraft

Information

  • Patent Grant
  • 6435923
  • Patent Number
    6,435,923
  • Date Filed
    Monday, July 10, 2000
    24 years ago
  • Date Issued
    Tuesday, August 20, 2002
    22 years ago
Abstract
A two-speed transmission (30) with reverse gearing for a watercraft (10). The transmission is disposed in the gimbal housing (25) passing through the transom (14) of the watercraft. A pair of planetary gears (46,80) share a common ring gear (40) to provide both forward-reverse and first-second gearing in a very compact package. The transmission housing may be formed in two portions, a first housing (32) containing the forward-reverse gear mechanisms and a second housing (62) containing the first-second gear mechanism. The transmission output shaft (64) is connected to the drive shaft (122) of a vertical drive unit (24) by a double universal joint (74) that may be replaced without disassembling the transmission components.
Description




BACKGROUND OF THE INVENTION




The present invention relates generally to the field of watercraft, and more particularly to the field of marine propulsion systems, and specifically to a two speed transmission with forward-reverse gearing for a watercraft wherein the transmission housing forms the gimbal housing of an in-board/out-board drive unit.




In conventional single speed marine drives, an engine is mechanically coupled to a propeller either directly or through a gear box to provide a single gearing ratio. It is known that a single gear ratio connection between the engine and propeller will provide less than optimal performance for many applications. There have been efforts to improve the performance of marine propulsion systems by the use of multi-speed and hydraulically coupled transmissions. It is known that the performance of a watercraft may be improved by providing a higher gear ratio connection between the engine and the propeller for low speed operation and acceleration, and by providing a direct drive or overdrive gear ratio between the engine and the propeller for high speed operation. In this manner, the engine may be operated at a point closer to its peak power output during a wider range of operating conditions.




U.S. Pat. No. 5,711,742 issued on Jan. 27, 1998, to Leinonen, et. al., incorporated by reference herein, describes a multi-speed marine propulsion system with an automatic shifting mechanism. An automatic transmission is interposed between the engine and the in-board/out-board drive apparatus. Although providing improved performance when compared to prior art single speed propulsion systems, the device of Leinonen creates an excessively long drive line which necessitates the placement of the engine in a more forward position within the watercraft hull than may otherwise be desirable.




U.S. Pat. No. 4,820,209 issued on Apr. 11, 1989, to Newman, incorporated by reference herein, describes a marine propulsion system having a fluid coupling with a variable power output. While this system avoids the long drive line of the Leinonen apparatus, it does so at the expense of multi-speed gear ratios. In lieu of multi-speed gears, the device of Newman provides for a controlled slippage between the engine and the propeller in order to improve low speed watercraft operation. The hydraulic coupling and forward-reverse gearing of the Newman transmission are enclosed within a housing passing through the transom of the watercraft, which in turn connects to the vertical drive unit containing the propeller. The device of Newman fails to provide a direct mechanical connection between the engine and the propeller at a plurality of gearing ratios.




BRIEF SUMMARY OF THE INVENTION




Thus, there is a particular need for an improved multi-speed mechanical drive transmission for a watercraft. Accordingly, a transmission for a watercraft is described herein as including: a first housing adapted for attachment to a motor; an input shaft rotatably supported by the first housing; a first housing output gear rotatably supported by the first housing; a forward-reverse shifting apparatus supported in the first housing for selective engagement between the input shaft and the first housing output gear in one of a forward and a reverse directions; a second housing attached to the first housing; an output shaft rotatably supported by the second housing; and a connection between the first housing output gear and the output shaft for providing rotation of the output shaft in response to rotation of the first housing output gear.




One embodiment of such a transmission is disclosed herein as including a housing; a input shaft rotatably supported by the housing; a output shaft rotatably supported by the housing; a first sun gear attached to and concentric with the input shaft for rotation therewith; a ring gear; a first planetary gear engaged between the first sun gear and the ring gear, the first planetary gear having a axis of rotation affixed to a carrier; a forward clutch disposed between the input shaft and the carrier and operable for selective engagement therebetween; a reverse clutch disposed between the housing and the carrier and operable for selective engagement therebetween; a second sun gear; a second planetary gear engaged between the second sun gear and the ring gear, the second planetary gear attached to the output shaft for rotation therewith; a first gear clutch disposed between the sun gear and the housing and operable for selective engagement therebetween; a second gear clutch disposed between the output shaft and the sun gear for selective engagement therebetween.




A marine propulsion apparatus is described herein as having: an engine having an output; a first housing attached to the engine; an input shaft rotatably supported by the first housing; a first sun gear attached to and concentric with the input shaft for rotation therewith; a ring gear; a first planetary gear engaged between the first sun gear and the ring gear, the first planetary gear having a axis of rotation affixed to a carrier; a forward clutch disposed between the input shaft and the carrier and operable for selective engagement therebetween; a reverse clutch disposed between the housing and the carrier and operable for selective engagement therebetween; a second housing adapted for attachment to the first housing; an output shaft rotatably supported by the second housing and operatively connected to the ring gear for rotation therewith; a vertical drive housing attached to the second housing; a drive shaft rotatably supported by the vertical drive housing and attached to the output shaft; and a propeller connected to the drive shaft.




The transmission described herein may be incorporated into a watercraft including: a hull having a transom; an engine disposed within the hull and having an output; a gimbal housing attached to the engine and passing through the transom; a vertical drive housing rotatably attached to the gimbal housing; a transmission comprising a first-second gear shifting apparatus disposed within the gimbal housing, the transmission having an input attached to the engine output and an output; a drive shaft rotatably disposed in the vertical drive housing and having an input end attached to the transmission output and an output end; and a propeller attached to the drive shaft output end.











BRIEF DESCRIPTION OF THE DRAWINGS




The features and advantages of the present invention will become apparent from the following detailed description of the invention when read with the accompanying drawings. Similar parts appearing in multiple figures may be numbered consistently among the figures, in which:





FIG. 1

is a partial sectional view of a watercraft having an in-board/out-board propulsion system including a two-speed transmission with reverse gearing disposed in the gimbal housing passing through the transom of the watercraft.





FIG. 2

is a partial sectional view of a forward-reverse housing portion of one embodiment of a transmission that may be used in the watercraft of FIG.


1


.





FIG. 3

is a partial sectional view of a first-second gear housing portion of a transmission that may be coupled to the forward-reverse housing portion of FIG.


2


.





FIG. 4

is a schematic illustration of a shift control apparatus that may be used to control the shifting of the transmission of FIGS.


1


and


2


.











DETAILED DESCRIPTION OF THE INVENTION





FIG. 1

illustrates a watercraft


10


having a hull


12


including a transom


14


. A marine propulsion apparatus


16


for the watercraft


10


includes an engine


18


attached to the hull


12


by one or more engine mounts


20


as is customary in the art. Attached to the engine


18


and extending through an opening


22


in transom


14


is gimbal housing


25


which forms a part of and is the housing for a multi-speed automatic transmission


30


. A vertical drive housing


24


is pivotally attached to an outboard portion of gimbal housing


25


and includes a torpedo section


26


disposed ahead of a propeller


28


. The gimbal housing


25


and the vertical drive housing


24


together are referred to as a stern drive unit. The vertical drive housing


24


may be rotated about both vertical and horizontal axes for steering and trimming the watercraft and for raising the propeller


28


to an uppermost position for operation in shallow water and for ground transportation. As will be described more fully below with respect to

FIGS. 2 and 3

, gimbal housing


25


encloses and supports both a forward-reverse shifting apparatus


42


and first-second gear shifting apparatus


78


. By incorporating a multi-speed transmission with reverse gearing into the gimbal housing


25


, the propulsion apparatus


16


is adapted to be used in place of a standard single speed inboard/outboard marine propulsion system. The inventor has found that by using two sets of planetary gears having a common ring gear, that a two-speed transmission with reverse gearing capability may be provided as a very compact unit, thus permitting it to be packaged within the space provided by the gimbal housing of an inboard/outboard marine propulsion unit.





FIG. 2

is a partial cross-sectional view of one embodiment of transmission


30


as may be used for watercraft


10


. Transmission


30


includes a forward-reverse housing


32


which may form a forward inboard portion of gimbal housing


25


of FIG.


1


. Housing


32


is adapted to be attached to engine


18


and is formed to fit around the engine output flywheel


34


. An input shaft


36


is rotatably supported within the housing


32


by one or more bearings


38


. Input shaft


36


is mechanically connected to and concentric with flywheel


34


for conveying mechanical energy into the transmission


30


via rotation with the output


34


of engine


18


. Mechanical energy is conveyed out of the forward-reverse housing


32


via a forward-reverse housing output such as ring gear


40


, which is operatively engaged with input shaft


36


. A forward-reverse shifting apparatus


42


is supported by housing


32


for selective engagement between the input shaft


36


and the output ring gear


40


in one of a forward and a reverse direction. Forward-reverse shifting apparatus


42


includes a sun gear


44


attached to and concentric with the input shaft


36


for rotation therewith, and one or more first planetary gears


46


engaged between the first sun gear


44


and the ring gear


40


. Planetary gears


46


are disposed between the first sun gear


44


and the ring gear


40


about the axis of rotation of input shaft


36


, as is in known in the art of planetary gears. Each of the planetary gears


46


is rotatable about an axis of rotation


48


that is supported by a carrier


50


. Carrier


50


is supported for rotation about input shaft


36


by bushings. Forward-reverse shifting apparatus


42


also includes a forward gear clutch


52


disposed between the input shaft


36


and the carrier


50


. Forward gear clutch


52


may be any design clutch known in the art, and may be a hydraulically actuated clutch operable for selective engagement and disengagement between input shaft


36


and carrier


50


. A reverse gear clutch


54


is disposed between the carrier


50


and the housing


32


and is operable for selective engagement therebetween.




Forward-reverse shifting apparatus


42


is operable to engage input shaft


36


to ring gear


40


for rotation of ring gear


40


alternatively in a forward direction or in a reverse direction. For forward operation, forward gear clutch


52


is engaged to prevent relative movement between the carrier


50


and the input shaft


36


, and reverse gear clutch


54


is disengaged to allow relative movement between the carrier


50


and the housing


32


. The engagement and disengagement of the clutches may be controlled by alternatively connecting and disconnecting a supply of pressurized hydraulic fluid, as will be described more fully below. The rotation of input shaft


36


will thereby cause the axis of rotation


48


of planetary gear


46


to rotate with sun gear


44


. As is known in the art of planetary gears, by locking the relative positions of the sun gear


44


and planetary gears


46


, ring gear


40


is caused to rotate in the same direction as input shaft


36


, i.e. in a forward direction. For reverse operation, forward gear clutch


52


is released to allow input shaft


36


to rotate relative to carrier


50


, and reverse gear clutch


54


is engaged to affix carrier


50


relative to housing


32


. With carrier


50


in a fixed position, planetary gears


46


are free to rotate about their respective axes of rotation


48


in response to the rotation of input shaft


36


and its attached first sun gear


44


. Due to the rotation of planetary gears


46


about their axis of rotation


48


, ring gear


40


is caused to rotate in a direction opposite to that of input shaft


36


, i.e. in a reverse direction. It may be appreciated that in the forward direction, the rate of rotation of ring gear


40


will be equal to the rate of rotation of input shaft


36


. However, in the reverse direction, the rate of rotation of ring gear


40


may be a ratio of the rate of rotation of input shaft


36


due to the action of the planetary gear set


44


,


46


,


40


. A predetermined gearing ratio in the reverse direction may be selected to provide ring gear


40


with a desired higher rate of rotation in the reverse direction, such as a 1.5:1 ratio, for example.





FIG. 2

also illustrates a geroter pump


56


attached to input shaft


36


. Geroter pump


56


provides hydraulic fluid at an elevated pressure through output


58


. One such geroter pump known in the art is provided by Nichols Portland, Inc. Pressurized hydraulic fluid provided by pump


56


may be utilized to operate first and second gear clutches


52


,


54


. One or more seal rings


60


may be provided on input shaft


36


on one or both sides of geroter pump


56


in order to limit the leakage from the pump and thereby to improve the low speed performance of pump


56


.





FIG. 3

illustrates a partial cross-sectional view of a first-second gear portion of transmission


30


showing first-second gear housing


62


which is adapted for connection to the forward-reverse housing


32


illustrated on FIG.


2


. An output shaft


64


is rotatably supported within housing


62


by one or more bearings, such as double ball bearing


66


. Output shaft


64


has an input end


68


operable to be journalled to an output end


70


of input shaft


36


, as illustrated on

FIG. 2

, for providing additional support between the shafts when housing


32


is connected to housing


62


. Output shaft


64


is connected at its output end


72


to a double universal joint


74


, as will be described more fully below. Housing


62


is adapted to extend through opening


22


of transom


14


as illustrated on

FIG. 1. A

transom seal flange


76


is adapted for connection to a flexible boot (not shown) for providing a water tight seal between first-second gear housing


62


and transom


14


.




Gimbal housing


25


and vertical drive housing


24


are supported in cantilever fashion from engine


18


, as shown in FIG.


1


. Because it is flexible, the boot forming the water tight seal between the propulsion apparatus


16


and the transom


14


is not capable of carrying any substantial support load. Thus, the stern drive unit is effectively isolated from the hull


12


by its support through the engine


18


and engine mounts


20


.




A first-second gear shifting apparatus


78


is disposed within housing


62


for providing a selective gearing connection between output shaft


64


and ring gear


40


. Ring gear


40


is illustrated in phantom in

FIG. 3

to illustrate its position when housing


62


is attached to housing


32


. Ring gear


40


provides a mechanical energy input through forward-reverse housing


32


from engine


18


. A second planetary gear


80


is engaged between ring gear


40


and a second sun gear


82


to form a planetary gear set for providing multi-speed capability for transmission


30


. One or a plurality of second planetary gears


80


are supported for rotation about their respective axes of rotation


84


by a carrier


86


which is attached to and rotates with output shaft


64


. A first gear clutch


88


is positioned for selective engagement between second sun gear


82


and housing


62


. A second gear clutch


90


is positioned for selective engagement between second sun gear


82


and output shaft


64


. Thus by selectively engaging and disengaging clutches


88


,


90


, sun gear


82


may be made free to rotate concentrically about output shaft


64


or to be locked into a fixed position around output shaft


64


.




Mechanical energy from engine


18


is delivered in the form of forward or a reverse direction rotation of ring gear


40


, as described above. For first gear operation, first gear clutch


88


is engaged to prevent the relative movement of sun gear


82


with respect to housing


62


, while second gear clutch


90


is disengaged to permit the rotation of output shaft


64


within second sun gear


82


. Because second sun gear


82


is in a fixed position, the rotation of ring gear


40


will induce the rotation of carrier


86


and its attached output shaft


64


due to the rotational movement of second planetary gear


80


about its axis of rotation


84


. The direction of rotation of output shaft


64


will be the same as the direction of rotation of ring gear


40


, however a predetermined gearing ratio, such as for example 1.33:1, will be developed through the action of the second planetary gear


80


. This gearing ratio provides a low gear operating capability for transmission


30


.




For operation in second gear, first gear clutch plate


88


is disengaged and second gear clutch plate


90


is engaged, thereby causing second sun gear


82


to rotate with output shaft


64


. In this alignment, because carrier


86


is attached for rotation with output shaft


64


, the rotation of ring gear


40


will cause the coupled rotation of second planetary gear


80


, second sun gear


82


, and output shaft


64


in the same direction and at the same speed as ring gear


40


.




In one embodiment, first-second gear shifting apparatus


78


, or alternatively a much simpler mechanism not having planetary gears or clutches, is locked in the second gear configuration to provide a direct drive connection between ring gear


40


and output shaft


64


. For example, a single gear attached to output shaft


64


and engaging ring gear


40


may be used to replace second sun gear


82


, second planetary gear


80


and clutches


88


,


90


. Such an embodiment may be a lower cost option for a watercraft


10


where first-second gear transmission capability is not provided. This may be especially useful where the gimbal housing


24


is provided as having two portions


32


,


62


. First-second gear housing


62


may be provided in a one speed form without first-second gear shifting apparatus


78


or in a two-speed form with first-second gear shifting apparatus


78


. Shifting apparatus


78


may optionally be added at a later date, either as a gearing kit or as a complete first-second gear housing unit.





FIG. 4

is a schematic illustration of a control system for the transmission


30


of

FIGS. 2 and 3

. Pump


56


provides pressurized hydraulic fluid to clutches


52


,


54


,


88


,


90


through respective valves


92


,


93


,


94


,


96


. The control of pressurized hydraulic fluid to each clutch is preferably controlled independently, with a valve aligned with each respective clutch plate. Valves


92


,


93


,


94


,


96


may be any type of valve known in the art of hydraulic fluid control, such as a mechanical rotor valve or an electrical solenoid valve. Depending upon the desired control scheme, the function of any two of the valves may be provided by a double acting solenoid valve operable to provide pressurized hydraulic fluid from pump


56


alternatively to either of two clutches. Valves


92


,


93


,


94


,


96


are controlled by control signals


98


,


100


,


102


,


104


respectively. The control signals are generated by controller


106


in response to pre-programmed logic operating on predetermined input signals. Controller


106


may be any controller known in the art, such as a microprocessor, personal computer, or even a mechanical device. Controller


106


is illustrated as a microprocessor containing logic operative to receive as inputs a gear selector signal


108


, an engine speed signal


110


, an engine vacuum signal


112


, a throttle position signal


114


, and/or a propeller lock signal


116


. Any one or more of these inputs may be used and processed by any desired logic to provide a desired shifting pattern. Logic within controller


106


is operable to select the appropriate gear and to generate appropriate valve control signals


98


,


100


,


102


,


104


in response to the various input signals. For example, when the gear selector signal


108


indicates that the operator desires to move the watercraft


10


in a forward direction, and the engine speed signal


110


, vacuum signal


112


, and throttle position signal


114


indicate that the watercraft is accelerating from a slow speed, logic within controller


106


may select the forward-first gear for transmission


30


. Accordingly, clutches


52


,


90


must be moved to the engaged position and clutches


54


,


88


must be moved to the disengaged position. To achieve this configuration, controller


106


will generate appropriate output signals


98


,


100


,


102


,


104


to position valves


92


,


93


,


94


,


96


accordingly. Various other combinations of such signals may be generated when appropriate to place the transmission


30


into other gears, as illustrated in the following matrix of valve positions.



















GEAR




Valve 92




Valve 93




Valve 94




Valve 96











first forward




open




closed




closed




open






second forward




open




closed




open




closed






first reverse




closed




open




closed




open






second reverse




closed




open




open




closed






neutral




open




closed




closed




closed






prop lock




closed




closed




open




open














The “prop lock” gear refers to a gear where the propeller


28


is locked to prevent its rotation even with the engine


18


operating. Many prior art marine transmissions cause the propeller to rotate slowly when the transmission is in a neutral position. This unintended propeller rotation is the result of various mechanical interferences and hydraulic couplings acting through the transmission when it is in a neutral position. While the propeller will generally rotate at a speed slower than the engine idle speed, even such a slow movement of the propeller is sufficient to propel a watercraft through the water. Controller


106


may be programmed to mechanically lock the propeller


28


in relation to hull


12


when transmission


30


is in either a neutral or a special Propeller Lock position. In such a configuration, signals


98


,


100


,


102


,


104


are generated to position valves


92


,


93


,


94


,


96


to provide pressurized hydraulic fluid to each of clutches


88


and


90


but not to clutches


52


and


54


. In this manner, output shaft


64


is mechanically affixed to housing


62


through second sun gear


82


, as illustrated in

FIG. 3

, and ring gear


40


is free to rotate with the engine


18


.




In one embodiment, a single rotary spool valve may be used to provide the functions of valves


92


,


93


to engage and disengage forward clutch


52


and reverse clutch


54


, together with a single two-position double acting spring loaded solenoid valve to provide the functions of valves


94


,


96


to engage and disengage first gear clutch


88


and second gear clutch


90


. The solenoid is preferably spring biased toward the second gear position so that in the event of an electrical failure, the transmission will stay in second (higher) gear.




Referring again to

FIG. 3

, it can be seen that double universal joint


74


is affixed at one end to output shaft


64


by fastener


120


threadably engaged with the output end


72


of output shaft


64


. The opposed end of universal joint


74


is inserted into and splined to a portion of a drive shaft


122


which is rotatably supported within vertical drive housing


24


, as illustrated in FIG.


1


. The drive shaft


122


may include one or more gears for transferring power from the universal joint


74


to propeller


28


. A flexible bellows


124


is sealingly attached to both the vertical drive housing


24


and the gimbal housing


24


in order to prevent water from coming into contact with universal joint


74


. In the event that the universal joint


74


must be replaced, as sometimes happens due to the leakage of water past bellows


124


, such replacement may be conveniently accomplished without the removal of the gimbal housing


24


or any of the associated parts of transmission


30


. Once the vertical drive housing


24


is detached from first housing


62


, the universal joint


74


may be partially disassembled to provide access to fastener


120


. Fastener


120


is then removed to allow removal of the remainder of the yoke


126


of universal joint


74


and the installation of the replacement part.




Referring again to

FIG. 2

, it can be seen that hydraulic fluid is drawn from a sump (not shown) to both sides of the inlet of gerotor pump


56


by passages


128


,


130


. Pressurized hydraulic fluid is directed away from the pump outlet by passage


132


toward valves


92


,


93


,


94


,


96


which may be mounted atop the housing


32


. A plurality of channels are shown to be formed in input shaft


36


for the passage of pressurized hydraulic fluid. A first channel


134


directs pressurized hydraulic fluid to a plurality of outlets associated with the various gears of forward-reverse shifting apparatus


42


. A second channel


136


extending into output shaft


64


directs pressurized hydraulic fluid to second gear clutch


90


, and a third channel


138


directs pressurized hydraulic fluid to forward clutch assembly


52


. Additional channels are formed in front bearing housing


144


which forms one half of the housing for geroter pump


56


. The second half of the pump housing is formed by plate


146


. Front bearing housing


144


and plate


146


are sealed against outer housing


32


by O-rings


148


,


150


. Item


149


indicates the location of a drive key on shaft


36


for gerotor pump


56


, although the drive key is not visible in the view of FIG.


2


.




Forward clutch assembly


52


includes clutch disks


152


,


154


and friction disk


156


which are urged together against hub


158


by piston


159


. Retaining ring


160


provides the reaction force for the forward clutch assembly


52


. Spring


162


, supported by retaining ring


161


, thrust bearing


163


, and thrust washer


165


, provides the return force to release the clutch when pressure is removed.




Reverse clutch assembly


54


includes clutch disks


164


,


166


,


168


and friction disk


170


urged together by piston


172


. Retaining ring


174


provides the reaction force for return spring


176


, and retaining ring


178


retains the opposed side of the clutch assembly.




Sun gear


40


is retained on input shaft


36


by retaining ring


180


. Axial loads transmitted through retaining ring


184


from ring gear


40


are reacted by hub and bushing assembly


182


. A thrust bearing


186


is located on each side of sun gear


40


, with thrust washer


188


being interposed between thrust bearing


186


and retaining ring


180


.




Ball bearing


190


is held in position against input shaft


36


by retaining rings


192


and against front bearing housing


144


by retaining ring


194


. Oil seal


196


provides a seal between the shaft


36


and housing


36


. Needle bearing


198


provides additional support for shaft


36


against plate


146


. Other various seal rings and O-rings can be seen in

FIG. 2

for providing appropriate protection against leakage and pressure boundaries for the pressurized hydraulic fluid.




Referring again to

FIG. 3

, it can be seen that first gear clutch assembly


88


includes clutch disks


200


,


202


and friction disk


204


urged together by piston


206


. Spring assembly


208


, supported by retaining rings


210


,


212


, provides a return force for releasing the clutch when hydraulic pressure is released. Clutch disk


200


is made to be L-shaped to provide room for locating spring assembly


208


.




Second gear clutch assembly


90


includes clutch disks


214


,


216


and friction disk


218


, urged together between hub


219


and retaining ring


221


by piston and check valve assembly


220


. The check valve portion of piston and check valve assembly


220


allows the pressurized hydraulic fluid to drain out of the piston once it has been depressurized.




First-second shifting apparatus is retained on output shaft


64


by retaining ring


222


. Seal


224


provides an oil barrier between yoke


126


and bearing retainer


224


, while O-ring


226


seals the opposed side of yoke


126


against shaft


64


. Other various seal rings and O-rings can be seen in

FIG. 3

for providing appropriate protection against leakage and pressure boundaries for the pressurized hydraulic fluid.




While the preferred embodiments of the present invention have been shown and described herein, it will be obvious that such embodiments are provided by way of example only. Numerous variations, changes and substitutions will occur to those of skill in the art without departing from the invention herein. Accordingly, it is intended that the invention be limited only by the spirit and scope of the appended claims.



Claims
  • 1. A transmission for a watercraft comprising:a housing; an input shaft rotatably supported by the housing; an output shaft rotatably supported by the housing; a first gear attached to and concentric with the input shaft for rotation therewith; a ring gear; a first planetary gear engaged between the first sun gear and the ring gear, the first planetary gear having an axis of rotation affixed to a carrier; a forward clutch disposed between the input shaft and the carrier and operable for selective engagement therebetween; a reverse clutch disposed between the housing and the carrier and operable for selective engagement therebetween; a second sun gear; a second planetary gear engaged between the second sun gear and the ring gear, the second planetary gear attached to the output shaft for rotation therewith; a first gear clutch disposed between the second sun gear and the housing and operable for selective engagement therebetween; and a second gear clutch disposed between the output shaft and the sun gear for selective engagement therebetween.
  • 2. The transmission of claim 1, further comprising:a geroter pump attached to the input shaft for providing pressurized hydraulic fluid to each of the forward clutch, reverse clutch, first gear clutch and second gear clutch, and a valve in fluid communication between the geroter pump and each of the forward clutch, reverse clutch, first gear clutch and second gear clutch for controlling the selective engagement of the respective clutch.
  • 3. The transmission of claim 2, further comprising:a double acting solenoid valve in fluid communication between the geroter pump and each of the forward clutch and the reverse clutch for alternatively selecting engagement of one of the forward clutch and the reverse clutch.
  • 4. The transmission of claim 2, further comprising:a controller connected to each respective valve for controlling the selective engagement of each respective clutch.
  • 5. The transmission of claim 4, further comprising logic in the controller operable to simultaneously engage the first gear clutch and the second gear clutch and to disengage the forward clutch and the reverse clutch.
  • 6. The transmission of claim 2, further comprising at least one seal ring disposed to be in sealing contact with the input shaft proximate the geroter pump.
  • 7. The transmission of claim 1, further comprising:the input shaft having an input end adapted for connection to an engine and an output end; the output shaft having an output end adapted for connection to a propeller and an input end; the input end of the output shaft being journalled to the output end of the input shaft.
  • 8. The transmission of claim 2, further comprising:a double acting solenoid valve in fluid communication between the geroter pump and each of the first gear clutch and the second gear clutch for alternatively selecting engagement of one of the first gear clutch and the second gear clutch; wherein the double acting solenoid valve is spring biased toward the second gear position.
  • 9. A transmission for a marine stern drive propulsion apparatus, the transmission comprising:a first housing adapted for attachment to an engine; an input shaft rotatably supported by the first housing; a first sun gear attached to and concentric with the input shaft for rotation therewith; a ring gear; a first planetary gear engaged between the first sun gear and the ring gear, the first planetary gear having a axis of rotation affixed to a carrier; a forward clutch disposed between the input shaft and the carrier and operable for selective engagement therebetween; a reverse clutch disposed between the housing and the carrier and operable for selective engagement therebetween; a second housing adapted for attachment to the first housing; an output shaft rotatably supported by the second housing and adapted for connection to a propeller drive shaft, the output shaft connected to the ring gear for rotation therewith.
  • 10. The transmission of claim 9, further comprising:a second sun gear; a second planetary gear engaged between the second sun gear and the ring gear, the second planetary gear having an axis of rotation attached to the output shaft for rotation therewith; a first gear clutch disposed between the sun gear and the housing and operable for selective engagement therebetween; a second gear clutch disposed between the output shaft and the sun gear for selective engagement therebetween.
  • 11. A transmission for a marine stern drive propulsion apparatus, the transmission comprising:a first housing adapted for attachment to a motor; an input shaft rotatably supported by the first housing; a first housing output gear rotatably supported by the first housing; a forward-reverse shifting apparatus supported in the first housing for selective engagement between the input shaft and the first housing output gear in one of a forward and a reverse directions; a second housing attached to the first housing; an output shaft rotatably supported by the second housing; a connection between the first housing output gear and the output shaft for providing rotation of the output shaft in response to rotation of the first housing output gear.
  • 12. The transmission of claim 11, wherein the connection between the first housing output gear and the output shaft further comprises a first-second gear shifting apparatus for selective engagement between the first housing output gear and the output shaft at one of a first gear ratio and a second gear ratio.
  • 13. The transmission of claim 11, wherein the forward-reverse shifting apparatus further comprises:a first sun gear attached to and concentric with the input shaft; a first planetary gear engaged between the first sun gear and the first housing output gear, the first housing output gear comprising a ring gear; and wherein the connection between the first housing output gear and the output shaft further a first-second shifting apparatus comprising: a second sun gear; and a second planetary gear having an axis of rotation attached to the output shaft, the second planetary gear engaged between the first housing output gear and the second sun gear.
  • 14. A marine propulsion apparatus comprising:an engine having an output; a transmission housing attached to the engine and adapted for passing through the transom of a boat; an input shaft rotatably supported by the transmission housing and connected to the engine output for rotation therewith; a output shaft rotatably supported by the transmission housing; a vertical drive housing rotatably connected to the transmission housing; a drive shaft rotatably supported by the vertical drive housing and connected to the output shaft; a propeller connected to the drive shaft; a first sun gear attached to and concentric with the input shaft for rotation therewith; a ring gear disposed in the transmission housing; a first planetary gear engaged between the first sun gear and the ring gear, the first planetary gear having a axis of rotation affixed to a carrier; a forward clutch disposed between the input shaft and the carrier and operable for selective engagement therebetween; a reverse clutch disposed between the transmission housing and the carrier and operable for selective engagement therebetween; a second sun gear disposed in the transmission housing; a second planetary gear engaged between the second sun gear and the ring gear, the second planetary gear having an axis of rotation attached to the output shaft for rotation therewith; a first gear clutch disposed between the sun gear and the transmission housing and operable for selective engagement therebetween; a second gear clutch disposed between the output shaft and the sun gear for selective engagement therebetween.
  • 15. The marine propulsion apparatus of claim 14, further comprising:a double universal joint connected between the output shaft and the drive shaft, the double universal joint comprising a first yoke in splined connection with the output shaft; and a connector for removeably retaining the first yoke on the output shaft.
  • 16. A marine propulsion apparatus comprising:an engine having an output; a first housing attached to the engine; an input shaft rotatably supported by the first housing and connected to the engine output for rotation therewith; a first housing output gear; a forward-reverse shifting apparatus in the first housing for selective engagement between the input shaft and the first housing output gear in one of a forward direction and a reverse direction; a second housing attached to the first housing; an output shaft rotatably supported by the second housing; a connection between the first housing output gear and the output shaft for providing rotation of the output shaft in response to rotation of the first housing output gear; a vertical drive housing attached to the second housing; a drive shaft rotatably supported by the vertical drive housing; and a propeller connected to the drive shaft.
  • 17. The marine propulsion apparatus of claim 16, wherein the forward-reverse shifting apparatus further comprises:a first sun gear attached to and concentric with the input shaft; a first planetary gear engaged between the first sun gear and the first housing output gear, the first housing output gear comprising a ring gear; a forward clutch disposed between the input shaft and the carrier and operable for selective engagement therebetween; a reverse clutch disposed between the housing and the carrier and operable for selective engagement therebetween; and wherein the connection between the first housing output gear and the output shaft further comprises a first-second shifting apparatus comprising: a second sun gear; a second planetary gear having an axis of rotation attached to the output shaft, the second planetary gear engaged between the first housing output gear and the second sun gear; a first gear clutch disposed between the sun gear and the housing and operable for selective engagement therebetween; and a second gear clutch disposed between the output shaft and the sun gear for selective engagement therebetween.
  • 18. A marine propulsion apparatus comprising:an engine having an output; a first housing attached to the engine; an input shaft rotatably supported by the first housing; a first sun gear attached to and concentric with the input shaft for rotation therewith; a ring gear; a first planetary gear engaged between the first sun gear and the ring gear, the first planetary gear having a axis of rotation affixed to a carrier; a forward clutch disposed between the input shaft and the carrier and operable for selective engagement therebetween; a reverse clutch disposed between the housing and the carrier and operable for selective engagement therebetween; a second housing adapted for attachment to the first housing; an output shaft rotatably supported by the second housing and operatively connected to the ring gear for rotation therewith; a vertical drive housing attached to the second housing; a drive shaft rotatably supported by the vertical drive housing and attached to the output shaft; a propeller connected to the drive shaft.
  • 19. A watercraft comprising:a hull having a transom; an engine disposed in the hull and having an output; a transmission housing attached to the engine; a input shaft rotatably supported by the transmission housing and connected to the engine output; a output shaft rotatably supported by the transmission housing; a first sun gear attached to and concentric with the input shaft for rotation therewith; a ring gear; a first planetary gear engaged between the first sun gear and the ring gear, the first planetary gear having a axis of rotation affixed to a carrier; a forward clutch disposed between the input shaft and the carrier and operable for selective engagement therebetween; a reverse clutch disposed between the transmission housing and the carrier and operable for selective engagement therebetween; a second sun gear; a second planetary gear engaged between the second sun gear and the ring gear, the second planetary gear attached to the output shaft for rotation therewith; a first gear clutch disposed between the sun gear and the transmission housing and operable for selective engagement therebetween; a second gear clutch disposed between the output shaft and the sun gear for selective engagement therebetween; a vertical drive housing attached to the transmission housing and passing through the transom; a drive shaft rotatably supported by the vertical drive housing and connected to the output shaft; a propeller connected to the drive shaft.
  • 20. The watercraft of claim 19, further comprising:a geroter pump attached to the input shaft for providing pressurized hydraulic fluid to each of the forward clutch, reverse clutch, first gear clutch and second gear clutch, and a valve in fluid communication between the geroter pump and each of the forward clutch, reverse clutch, first gear clutch and second gear clutch for controlling the selective engagement of the respective clutch.
  • 21. The watercraft of claim 20, further comprising a controller connected to each respective valve for controlling the selective engagement of each respective clutch.
  • 22. The watercraft of claim 21, further comprising logic in the controller operable to simultaneously engage the first gear clutch and the second gear clutch and to disengage the forward clutch and the reverse clutch, thereby locking the position of the propeller in relation to the position of the hull while allowing the engine output to rotate in relation to the hull.
  • 23. A watercraft comprising:a hull having a transom; an engine disposed in the hull and having an output; a first housing attached to the engine; an input shaft rotatably supported by the first housing and attached to the engine output for rotation therewith; a first housing output gear; a forward-reverse shifting apparatus disposed in the first housing for selective engagement between the input shaft and the first housing output gear in one of a forward direction and a reverse direction; a second housing attached to the first housing an passing through an opening in the transom; an output shaft rotatably disposed in the second housing; a first-second gear shifting apparatus connected between the first housing output gear and the output shaft for providing rotation of the output shaft in response to rotation of the first housing output gear at a selected one of a first gear ratio and a second gear ratio; a vertical drive housing attached to the second housing; a drive shaft rotatably supported by the vertical drive housing; and a propeller connected to the drive shaft.
  • 24. The watercraft of claim 23, wherein the forward-reverse shifting apparatus further comprises:a first sun gear attached to and concentric with the input shaft; a first planetary gear engaged between the first sun gear and the first housing output gear, the first housing output gear comprising a ring gear; a forward clutch disposed between the input shaft and the carrier and operable for selective engagement therebetween; a reverse clutch disposed between the housing and the carrier and operable for selective engagement therebetween.
  • 25. The watercraft of claim 24, wherein the first-second gear shifting apparatus comprises:a second sun gear in the second housing; and a second planetary gear having an axis of rotation attached to the output shaft, the second planetary gear engaged between the ring gear and the second sun gear; a first gear clutch disposed between the sun gear and the housing and operable for selective engagement therebetween; a second gear clutch disposed between the output shaft and the sun gear for selective engagement therebetween.
  • 26. A watercraft comprising:a hull having a transom; an engine disposed within the hull and having an output; a gimbal housing attached to the engine and passing through the transom; a vertical drive housing rotatably attached to the gimbal housing; a transmission comprising a first-second gear shifting apparatus disposed within the gimbal housing, the transmission having an input attached to the engine output and an output; a drive shaft rotatably disposed in the vertical drive housing and having an input end attached to the transmission output and an output end; a propeller attached to the drive shaft output end.
  • 27. The watercraft of claim 26, wherein the transmission comprises a first-second gear shifting apparatus and forward-reverse shifting apparatus.
  • 28. The watercraft of claim 26, further comprising:a double universal joint connecting the drive shaft input end and the transmission output, the double universal joint having a transmission end shaft connected to the transmission output; and a connector for removeably retaining the transmission end shaft in contact with the transmission output.
Parent Case Info

This application is a continuation-in-part of U.S. patent application Ser. No. 09/543,437 filed on Apr. 5, 2000, now U.S. Pat. No. 6,305,997.

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Entry
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Continuation in Parts (1)
Number Date Country
Parent 09/543437 Apr 2000 US
Child 09/613093 US