AU621654B2 - Improved engine transaxle combination - Google Patents

Description

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AUSTRALIA

Patents Act COMPLETE SPECIFICATION

(ORIGINAL)

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Application Number: Lodged: Complete Specification Lodged: Accepted: Published: Priority: Related Art: 0

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Applicant(s): Address for Service: Deere Com-r.ny John Deere -oad Moline ILLINOIS UNITED STATES OF AMERICA Kawasaki Heavy Industries Inc World Trade Center Building 4-1, Hamamatsu-cho, 2-Chome Minato-Ku TOKYO

JAPAN

ARTHUR S. CAVE CO.

Patent Trade Mark Attornerys Level 10, 10 Barrack Street SYDNEY NSW 2000 Complete specification for the invention entitled "Improved engine transaxle combination".

The following statement is a full description of this best method of performing it known to me:invention, including the 1 5020 i~ 3037T/lfg 1 :IMPROVED ENGINE/TRANSAXLE COMBINATION Background of the Invention The present invention relates to engine/transaxle combinations used as driving means for working vehicles.

FIG. 2 shows a conventional working vehicle 10 equipped for lawn mowing. The conventional work vehicle 10 includes a steering wheel 11, an operator's seat 13 and a mower deck 16 or other working implement which is conventionally operatively connected to the vehicle through two traction bars 17, 18. A drive unit 20 which includes an engine 21 is positioned between the two front wheels 22 and/or two rear wheels 24. As shown a conventional transaxle 26 is positioned on the mower deck 16 side of the rear wheels 24. Driving power is provided from the engine 21 to the mower deck 16. A V-belt system 28 is *operatively positioned between the engine 21 and the mower deck f ':16 for transmitting power from the engine 21 to the mower deck or other implement.

In the central portion 30 of the transaxle, a speed reduction unit and a differential unit (not shown) are operatively positioned in close proximity to each other, as shown in Japanese Patent unexamined publication No. 56-23065.

In the conventional structure, a first V-belt 32 is provided for transmitting power between a belt pulley 33 operatively connected to the output end of the engine crankshaft 34 and a second belt pulley 36 operatively connected to an intermediate shaft 38 which is conventionally connected to the transaxle 26.

A second V-belt 40 is provided for transmitting power between a third belt pulley 41 operatively connected to the internediate shaft 28 and a fourth belt pulley 42 operatively connected to the input shaft 43 of the mower deck 16 or working implement.

With the conventional vehicles, the intermediate shaft 38 having the second 36 and third 38 pulleys is required because the relative thickness of the central portion 30 of the conventional transaxle prevents the mower deck 16 or other attached implements from having sufficient operational vertical movement or float relative to the work vehicle. Therefore, utilizing a single V-belt between the engine output shaft 24 and the input shaft 43 of the work implement to transmit power is not practical because the conventional intermediate shaft 38 with pulleys provides the ability for the V-belt connecting the la 1 intermediate shaft and the implement to float vertically in response to convex or concave conditions in the operating surface without interference between the belt and the conventional thick transaxle housing. Specifically, as shown, with the intermediate shaft 38, if the mower deck 16 is moved vertically, the second 40 V-belt will move vertically, but the first V-belt 32 will not move vertically. Therefore, with this conventional construction, the central thick portion 30 of the transaxle is prevented from contacting or interfering with the first V-belt.

However, in the above described conventional structure the distance between the intermediate shaft 38 and the implement input shaft 43 is relatively short dnd the second V-belt 40 will reach its maximum acceptable belt misalignment angle 80) for extended operations with rather limited vertical :movement of the mower deck when compared to the vertical movement possible by utilizing a longer belt. Thus, because of the conventional transaxle structure, two belts and an intermediate shaft and pulleys are required resulting in increased cost and complexity, not to mention the restricted vertical float. Further the conventional two belt system is apparently subjected to increased bending frequency thereby S resulting in reduced service lives for the V-belts.

In order to increase the actual ep vertical float distance, it appears necessary to increase the distance from the engine output shaft pulley to the implement input shaft pulley in order to increase the distance above and below the normal level implement position because which the implement can float. This is due to the acceptable belt misalignment angle mentioned above. Specifically, as the distance between the engine output crankshaft pulley and the implement input pulley decreases, the smaller the distance above and below the normal level implement position the implement can float without exceeding the belt misalignment angle. Because with the conventional pulley and belt system utilized to transmit power from the engine output crankshaft to the implement input shaft having two pulleys and an intermediate shaft, the conventional system is restricted relative to the belt's misalignment angle above and below the implement level plane. In other words, the shorter the distance f any one belt, the less the distance the implement can deviate 2-

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IIs 1 from both above and below the level implement position without exceeding the belt misalignment angle.

With the conventional structure, the intermediate shaft is required partially because the engine crankshaft and the transaxle centerline have been separated by such a relatively great distance. Therefore, utilization of one belt for transmitting power from the engine output shaft to the implement input shaft was impractical. Specifically, even if there were sufficient clearance between a single belt and a lower portion of the transaxle housing to enable the belt to pass thereunder and to allow some vertical float, since the distance separating the engine crankshaft and the transaxle housing was relatively •o.great, the vertical float angle provided at the engine crankshaft pulley was less in the vertical direction than the belt misalignment angle due to interference between the belt and the bottom portion of the transaxle.

OQ ~An additional problem encountered with conventional engine transaxle arrangements during the development of the present "es.

invention involved how you assemble the engine and transaxle into a unit while maintaining an acceptable vehicle center of gravity simultaneously with an acceptable clearance between the o bottom of the engine output shaft and the ground. With the S..engine and the conventional transaxle configured as a unit, the vehicle center of gravity was too high for use in front mount o2". mower-type vehicles and the conventional hydrostatic transaxle drive arrangement whereby the hydropump was conventionally driven by the engine crankshaft provided an adequate ground clearance for the engine crankshaft.

With conventional engine transaxle configurations, having hydrostatic transmissions, separate lubricating systems have been used to separately lubricate the engine, the differential and to provide hydraulic fluid for the hydrostatic transmission. If the hydrostatic fluid system and the engine lubricating fluid system along with the transaxle system could be interconnected, a simpler, more serviceable unit would result.

Accordingly, there is a need for an improved engine transaxle combination which eliminates the intermediate shaft and the two pulleys; which provides adequate clearance so that a single V-belt can be connected directly between the engine 3- I i.

0525k/SC 4 output shaft and the mower deck or other working implement input shaft; which simplifies the connection between the engine output shaft and the mower deck or other working implement.

SUMMARY OF THE INVENTION The present invention is a vehicle having ground engaging wheels, adapted to support a work implement capable of vertical float relative to the vehicle comprising: an engine carried on the vehicle and having an,,output shaft; an elongated transaxle housing carried by the vehicle and operatively positioned between the engine and the I implement, said transaxle housing including first and second spaced apart portions having a greater cross section than a S: third portion therebetween; axle means carried within the transaxle housing and operatively coupled to driven wheels; power transmission means coupled with and extending from the output shaft of the engine, between the first and second portions, adjacent to the third portion of the transaxle housing, and coupled to drive means of the implement for drivingly powering the implement asit.

encounters vertical float relative to said engine.

In the preferred embodiment of the engine/transaxle unit, a single V-belt connects the engine output shaft and the implement input shaft and passes under the transaxle without interfering with the transaxle through the entire range of implement vertical float. This direct connection between the engine output shaft and the implement input shaft is made possible by the disclosed configuration of the engine and transaxle combination and by the arrang nent in the transaxle housing of certain component parts of the hydrostatic transmission and the transaxle including the hydromotor, a speed reduction gear unit and a differential unit.

0525k/SC In the preferred embodiment, a portion of the transaxle housing is utilized as an integral portion of the engine to comprise a unitized engine transaxle. However, it should be noted that the advantages provided by the present invention do not require that the engine and the transaxle have a common housing only that the various component parts be positioned so that the advantages of the combination are accomplished without regard to the particular manner in which the various components are assembled together.

For example, an important feature of some embodiments of the present invention includes the relative physical positioning of the engine to the transaxle and whether they are merely operatively connected together by connection means such as bolts, rivets welded etc or whether part of the engine is assembled into a portion of the transaxle housing itself is immaterial.

An additional important aspect of preferred embodiments of the present invention includes the lowering of the vehicle's center of gravity by positioning the engine as close to the center line of the axle as possible and by lowering the engine relative to the axle's center line while maintaining adequate clearance between the engine output shaft and the ground. Specifically, adequate output shaft ground clearance is maintained by driving the hydropump, which is attached to the exterior of the engine, by a gear S"mechanism located inside the engine, by the engine cam shaft.

An even further preferred embodiment of the present invention includes the utilization of common fluid between the hydrostatic transaxle, the reduction gear and the differential gear of the transaxle.

A still further preferred embodiment of the present invention includes the utilization of common fluid to lubricate the engine and as hydraulic fluid for the hydrostatic transmission, the axle and/or as lubrication for the differential.

i-i T 0 0525k/SC 6 BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of a front mount mower incorporating the combination engine transaxle of the present invention; FIG. 2 is a schematic perspective view with partial cut away portions illustrating a conventional engine transaxle combination mounted on a buggy; FIG. 3 is a schematic perspective view with cut away portions illustrating the utilizatoin of the present invention as would be mounted on the buggy of FIG. 2; FIG. 4 is a side view with portions but away of the engine of one embodiment of the engine transaxle combination of the present invention; FIG. 5 is a plan view of the engine with portions of the S" transaxle housing removed showing the internal arrangements of the various components; and r FIG. 6 is a view taken along line 6--6 of FIG. 4.

oc DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in FIG. 1, the preferred embodiment of the present invention includes a front mount mower 50, having an operator's station 52 including an operator's seat 54 and a steering wheel 56. A front mounted implement or mower deck 58 is operatively connected to the vehicle by a pair of connection members 60. The preferred embodiment includes an engine/transaxle combinatoin (FIG. 4) which are assembled into a unit preferably having at least a common partial housing member but can be operatively connected utilizing separate housing members for the engine and the transaxle by other conventional methods. As shown, in FIGS. 1 and 3 to 6 the front axle of the front mount mower 50 is utilized to power or drive the front wheels 64, therefore, the engine and transaxle 72 are preferably located underneath the operator's station 52.

I- ~~i 1 In order for the mower deck 58 to be driven by a single Vbelt 74 (see FIG. 3) connected to the engine crankshaft 76, clearance means 80 must be provided for allowing the V-belt 74 to pass from the engine crankshaft 76 underneath the transaxle housing 82 to the front mower deck 28 input shaft 86 (see FIG.

This clearance 80 must be sufficient to allow the mower deck 58 to have adequate vertical float such that the transaxle housing 82 does not contact or operationally interfere with the V-belt 74 during the transfer of power from the engine crankshaft to the mower deck 58.

In order to accomplish this, as shown in FIGS. 3 6, the engine/transaxle combination 90 of the present invention is assembled together with the engine vertical crankshaft 76 being positioned as close to the axle center line 92 as possible in order to have the pulley 94 (FIGS. 3 and 4) on the engine crankshaft 76 as close to the transaxle housing 82 as possible.

T-lis arrangement minimizes possible interference between the belt 74 and the lower portion of transaxle housing 96.

In order to provide a low vehicle center of gravity while still maintaining adequate clearance between the pulley 94 connected to the engine crankshaft 76 and the ground 98 (see FIG. the engine 70 is connected to the transaxle 72 as close to the ground 98 as possible.

In order to provide adequate clearance for the V-belt 74 under the transaxle housing 82, the differential gear 100 is positioned inside the transaxle housing 82 at a location preferably proximate the right front wheel of the vehicle In vehicles equipped with hydrostatic transmissions (see FIG.

the hydromotor 104 is also preferably operatively positioned inside the transaxle housing 82 at a location proximate the left front wheel of the vehicle. A speed reduction gear 108 is operatively positioned inside the transaxle housing 82 proximate the hydromotor 104. The specific locations of the differential 100, the hydromotor 104 and the speed reduction gear 108 can be varied within the transaxle housing 82 according to specific requirements, it being understood that other arrangements of the various sub-component parts can be placed in other positions than those illustrated and still be within the scope of the present invention.

-7- ~I Y r i i 1 In particular, one critical aspect of the present invention is the amount of clearance required by the V-belt 74 which connects the engine crankshaft 76 with the mower deck 58 or front implement input means. In FIGS. 1 and 3, the mower deck 58 is shown operating in a level surface. The V-belt 74 mounted between the engine crankshaft 76 and the mower deck input shaft 84b (see FIG. is shown in its normal level operation position. However, when the mower deck is caused to move either above or below the level position shown such as when encountering rough uneven terrain, the mower deck and the belt connected thereto deflect either upwardly or downwardly from the level position. Since most belt manufacturers recommend only a 50 belt misalignment angle from the level position, obviously the greater the distance between the engine crankshaft 76 and the implement input shaft 94 the greater the deflection above or below the level position the mower deck or implement can move without exceeding the 50 belt misalignment angle limitation.

Thus, the requirement that there be adequate clearance between the V-belt 74 and the lower portion 96 of the transaxle housing 82 to prevent the transaxle housing from interfering with V-belt cperation. This clearance 80 is obtained by the arrangement of the various sub-components within the transaxle housing 82.

Another consideration in the location of the various subcomponents in the transaxle housing 82 is the fluid flow from the engine sump 110 to the hydropump 112, the hydromotor 104 and back to th- hydropump 112. Leakage from this fluid flow system is preferably utilized to lubricate the speed reduction 1 gear 108 and/or the differential 100. After lubrication of the speed reduction gear unit 108 and/or the differential unit 100, the fluid is returned to the engine fluid sump 110.

In order to provide for the above, the following component parts combination was determined as being one of a plurality of possible combinations was might be satisfactory. As shown in the preferred embodiment FIGS 1 and 3 6, the preferred engine transaxle combination 90 includes a tubular transaxle housing 82 operatively connected to the engine 70. The transaxle housing 82 preferably includes at least a portion 83 which at least partially encases the engine 70. As shown in FIG. 5, the hydromotor 104 is positioned within the transaxle housing 82 -8 1 along with the speed reduction unit 108, the differential unit 100 and the axle 106 itself.

The hydraulic motor 104 includes a hollow axle carrier 114 which is rotatably supported at both ends by ball bearings 118 and needle bearings 120. A disk-shaped cylinder block 122 is slidably engaged with splines formed in the outer periphery of the carrier. A plurality of pistons 124 are equiangularly provided in a conical surface of the cylinder block 122. A thrust plate 126 is provided for receiving thrust from the pistons 124 which are rotatably supported within the axial housing 32 through needle bearings 120, so that the thrust plate 126 may rotate in a forward direction or a reverse direction.

An eccentric circular sleeve 127 is formed at one end of the carrier 116. The cylinder block 122 is used as a brake drum, therefore, a band brake 128 is provided around the cylinder block 122 to simplify the brake mechanism. In order to complete the hydrostatic transaxle, a variable hydraulic pump 112 is operatively positioned on the engine 70 and is driven by a cam shaft mechanism 130 (see FIG. 6) operatively positions inside the engine and connected to the crankshaft for supplying the power for operating the hydraulic motor 104.

This particular arrangement is important to the overall success of the combination,, Specifically by positioning the hydropump 112 on the exterior of the engine 70 and by driving it by a cam shaft gear system positioned inside the engine, the engine could be connected to the transaxle 72 at a position relatively closer to the ground than before. This relatively lower positioning provides for vehicle with a lower center of :.gravity thereby improving stability and also reducing the length of the crankshaft which extends from the bottom of the engine including the necessary pulley 94 and clutch 95 connected thereto thereby providing relatively increased distance between the pulley 94 and the ground.

Additionally, by reducing the distance between the engine crankshaft and the transaxle housing, the vertical distance r which the single belt moved toward the lower portion 96 of 'he transaxle housing 82 was reduced thereby increasing the distance the front mounted implement could move above the level positioned without having the lower portion of the transaxle housing 96 interfere with the belt 74.

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1 As shown in FIG. 5, the hydropump 112 is preferably operatively connected to the left lower side portion of the engine 70 of the preferred unitized engirie-transaxle combination As shown in FIG. 4, two fluid lines 160, 162 are utilized in fluid communication between the hydropump 112 and the hydromotor 116 one line for flow in each direction therebetween, depending upon whether the vehicle is operating in the reverse or the forward direction. Further details of the unitized engine transaxle configuration related to the present invention can be found in U. S. Serial-No. 161,026, filed 26 February 1988 which is a continuation in part of U. S. Serial No. 07/089,146, filed 26 August 1987, both of which are hereby incorporated by S: reference.

As shown in FIG. 6, a cam 130 mechanism for transferring power directly from the engine crankshaft 76 to the hydropump *112 input shaft 113 is illustrated. The hydropump 112 is directly connected to the engine 70 with a cam shaft 130 having a cam gear 170 operatively connected thereto positioned intermediate and parallel to the engine crankshaft 76 and the hydrostatic pump input shaft 113. The cam gear 170 includes two separate portions 172, 174 each having teeth 176, 176. One of the cam gear portions 172 intermeshes with matching teeth 180 on e. the engine crankshaft 76 and the other cam gear portion 174 intermeshes with mating teeth 182 on a gear 18 connection to the hydrostatic pump input shaft 113 The cam gear mechanism 130 shaft including the cam 131 and cam gear 170 is positioned inside the engine.

The driving or powering of the hydrostatic pump 112 by the cam gear mechanism 130, which is contained inside the engine, provides for increased distance between the end of engine crankshaft which protrudes below the engine and the ground thereby providing for increased ground clearance. The hydrostatic pump 112 and the engine crankshaft are otherwise conventionally constructed.

This particular structure for powering the hydrostatic pump also provides for the engine to be positioned closer relative to the ground in order to reduce the vehicle center of gravity and thereby to increase vehicle stability.

The speed reduction unit 108 is a planetary gear reduction type. Planetary pinions 132 are meshed with an outer periphery 10 io 1 of the circular sleeve portion 127 of the carrier 116 through ball bearings and inner teeth of a ring gear 134 are fixed to the axle housing and are meshed with the outer teeth of the planetary pinions 132. Splines are formed in the inner periphery of the boss portions of the planetary pinions 132. As shown, it is preferred that the planetary pinions 132 have one less tooth than the ring gear 134.

The differential unit 100 includes a tubular differential gear box 136 which is rotatably supported through ball bearings 138 on the opposite side within the axle housing. Operatively connected to the differential gear box 136 is an end shaft 140 member. A pair of small bevel gears 142 are rotatably pivoted in the inner peripheral portion of the differential gear box 136. A pair of large bevel gears 144 that engage with a pair of small bevel gears 142 are rotatably supported by the inner *S 'peripheries of the differential gear box 136 and the end shaft 140. Splines 146 are formed in an end portion of the shaft 140. The splines 135 of the planetary pinion 132 are operatively connected to the splines 146 of the shaft by an axial hollow spline joint 150.

The axle unit also includes a long axle member 152 and a :short axle member 154. The long axle member 152 is operatively .•connected at one end to an inner periphery of one of the large bevel gears 144 and projects at the other end from one side of 8>::-the axle housing 156 passing through the hollow apertures of the carrier 116 and the spline joint 150. The other end of the long axle is rotatably supported in the carrier 116 and the axle 'housing 3.56 through the needle bearings 120 and the ball bearings 118. The short axle 154 is connected to one end of the inner periphery of the other large bevel gear 144 through the splines and is rotatably supported at the other end on the other side of the axle housing through ball bearings projecting to the outside. The drive wheels 64 are fixed to the projecting portions of the long and short axles respectively.

In the preferred embodiment, in order to provide adequate belt clearance 80 under the transaxle housing 82, the diameter of the transaxle housing 82 is reduced as much as yossible so that the central portion will not interfere with the revolution of the end portion on the planetary pinions 132 of the spline joints 135. At the same time, as shown in FIG. 3, the axle 11 -j ll j 1 housing center line x-x is located above the centerline of the axle y-y. Thus, the clearance or space 80 is formed which provides adequate clearance for the V-belt 74 which connects the engine 70 with the working implement 58 to operate and still provide adequate implement vertical float.

During the operation of the hydraulic motor 104, the working fluid which leaks therefrom, flows through the transaxle housing into the differential unit chamber 100, and is returned back to the variable hydraulic pump 112 through a return pipe 190. In the preferred embodiment, the fluid is returned to the engine sump through internal means (not shown). In order to increase flow rate from the leakage of the hydraulic motor 104 through the differential unit 100, the fluid diameter of the passage 9@ from that point over to the differential has been decreased as much as possible. The working fluid is cooled by cooling fins f S (not shown) formed around the central portion as the passes through the decreased diameter passage.

In operation, working fluid is supplied to the hydraulic *6#O motor by the variable hydraulic pump 112 which is driven by the engine crankshaft 76. Rotation of the cylinder block causes the circular sleeve of the carrier 116 to eccentrically rotate at the same rotational speed. Therefore, the planetary pinion 132 46 0l are meshed and revolve with the ring gear 134 so that the planetary pinions 132 are rotated about their own axis in the 2 reverse direction to the revolution produced by the hydromotor reduced by the tooth ratio. The rotational motions of the planetary pinions 132 are transmitted to the shaft through the

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•spline joint 150. The action of the revolution is adapted to raise the spline joint on the ring gear 135 side by though the effect of the spherical splines 146, but is not transported to the shaft 140.

The shaft causes the differential box 136 to rotate and also causes the long 152 and short 154 axles to rotate through the engaged small 142 and large bevel gears 144, thus, rotating both the driving wheels. With the inclusion of the differential unit 100, when the vehicle is advanced slightly, the driving wheels are rotated the same rotational speeds, but when the vehicle is advanced along a curved path, the drive wheel on the outside of the curve path is rotated at a higher speed than the other drive wheel on the inside of the curve path which is conventional.

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i 1 On the other hand, the crankshaft 76 of the engine 70 is operatively positioned to drive the implement input shaft through the belt pulley. The V-belt 74 and the belt pulley 86 are operatively connected to the working implement through the clearance or space 80 created by the selective positioning of the transaxle components. Thus, even if the front mounted implement is moved vertically in response to the vehicles traversing uneven ground which may have hills and such, the space and the transaxle through which the V-belt passes is of a sufficient width and height so that the V-belt will not "interfere with the bottom surface of the transaxle housing.

":""With this construction, there is no need for the conventional %%intermediate shaft and the use of two belts, one from the engine to the intermediate shaft and the other from the intermediate shaft to the working implement. The result is significantly greater vertical float, decreased material manufacture and assembly cost and a lower vehicle center of gravity while maintaining adequate ground clearance for the engine output shaft 76.

While the method and operation herein described constitute preferred embodiments of the invention, it is to be understood that the invention is not limited to this precise method and operation, and the changes may be made therein without departing from the scope of the invention which is defined in the appended 5o', claims.

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Claims (10)

1. 2. The invention as defined in claim 1 wherein speed reduction means is carried in the first portion and o differential means is carried in the second portion of said c, transaxle.
2. 3. The invention defined in claim 2 wherein tubular drive means extends between the speed reduction means and the differential means, said tubular drive means passing though the third portion of the housing.
3. 4. The invention as defined in any one of claims i, 2 or 3 wherein the power transmission means includes a V-belt extending between the engine output shaft and the implement drive means. The work vehicle of claim 4 wherein said belt means comprises: first pulley means operatively connected to said engine output shaft; second pulley means operatively connected to said implement drive means; and RA4~ g. I i L .4 Vu L 1- V= UCI 3CILI .LaYLL ILLtLen dL1yJ. dUVVt: clIU UJALUW Lilt1 implement level plane. In other words, the shorter the distance of any one belt, the less the distance the implement can deviate S- S-2- 15 a single elastomeric belt operatively positioned in each of said first and second pulley means so that the rotation of said output shaft rotates said first pulley means thereby rotating said second pulley means for transferring power to said implement.
4. 6. The work vehicle of any one of claims 1 to 7 wherein a hydrostatic pump is operatively connected to said engine and a hydrostatic motor is operatively positioned in said transaxle.
5. 7. The work vehicle of any one of claims 1.to 6 wherein the output shaft is the crankshaft of the engine.
6. 8. The work vehicle of claim 7 wherein the crankshaft is vertical. p9. The work vehicle of any one of claims 6 to 8 further comprising: i- gear means operatively positioned inside said engine for transmitting power from said engine output shaft to said ean hydrostatic pump. The work vehicle of claim 9 wherein said gear means further comprises: ."hydcrankshaft gear teeth operatively connected to the crankshaft; -a cam shaft; and a a cam gear, operatively connected to said cam shaft, said cam gear having an upper and a lower portion each Shaving teeth means for interacting with said crankshaft teeth means and said hydrostatic pump input shaft.
7. 11. The work vehicle of claim 9 wherein said upper portion of said cam gear interacts with said crankshaft teeth and said lower portion of said cam gear interacts with said hydrostatic pump input shaft so that power is transmitted from.said engine crankshaft to said hydrostatic pump input shaft.
8. 12. The work vehicle of any one of claims 1 to 11 wherein said engine and said transaxle are operatively connected to form a unitized combination. L) transaxie comoDnation wnicn eliminates cne invueLiu.aa i onaiL and the two pulleys; which provides adequate clearance so that a single V-belt can be connected directly between the engine 3 1491 i ~i~r BI rr 0495k/SC 16
9. 13. The work vehicle of any one of claims 6 to 11 wherein: said hydrostatic pump is positioned on the same side of said engine as the end of said transaxle housing in which said hydrostatic motor is positioned.
10. 14. A work vehicle as substantially hereinbefore described and with reference to figs 1 and 3 to 6. DATED this 24th day of September, iiYl. DEERE COMPANY and KAWASAKI HEAVY INDUSTRIES INC. By Their Patent Attorneys ARTHUR S. CAVE CO. I .00V 0 sees 0 0 so** 0.04 S L I i; iL- i :r F( Y/1 i -I