← Back to Patent Explorer
US5289738A Expired / Lapsed US ⏱️ 0.0 years remaining

Hydrostatic transaxle assembly and improved coupling arrangement therefor

Assignee: Eaton Corp
•
Filing: 1992-11-23
•
Granted: 1994-03-01
•
Expires: 2012-11-23
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A hydrostatic transaxle is disclosed of the type including a hydrostatic transmission (11;221), a differential gear means (19;243), and first (21;213) and second (23;215) axle shafts. The hydrostatic transmission includes a transmission case (34;229,231) having a second case portion (31;231) including an output hub portion (97;235). The transaxle includes axle housing casing halves 133,135:209,211) joined together on a plane containing the axis of rotation of the axle shafts, and including an output portion (163,165;209,211) in tight engagement about the output hub portion. Another portion (173;229,231,249) of the transmission case cooperates with one of the axle casing halves to define a secondary mounting means and a torque reaction means which, together with the output hub portion, comprise the only portions of the transmission case operatively associated with the axle housing (131;208). The disclosed mounting or coupling of the hydrostatic transmission and the axle housing makes it possible to integrate the hydrostatic transmission and gear axle assembly, while at the same time segregating the hydraulic fluid of the hydrostatic transmission from the lubricant of the gear axle assembly, but still simplifying the overall structure of the assembly.

Inventors

  • 👤 Dennis E. Szulczewski

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 05:32
CPC Classifications
F; F16; F16H; F16H57/00; F16H57/02; F16H57/037; B; B60; B60K; B60K17/00; B60K17/04; B60K17/10; B60K17/105; F16H2057/02039; F16H2057/02043; F16H2057/02052; F16H2057/02056; F16H57/023; F16H2057/0235; Y; Y10; Y10T; Y10T74/00; Y10T74/21; Y10T74/2186

Claims Analysis

Total Claims: 22
Claim 1
Independent Claim 282 words
A hydrostatic transaxle of the type including a hydrostatic transmission having an input means, a hydrostatic pump driven by said input means, a hydrostatic motor, and an output means driven by said motor; and an axle assembly having a differential gear means including an input gear and first and second output gears, first and second axle shafts driven by said first and second output gears, respectively, and an output gear train operable to transmit torque from said output means of said hydrostatic transmission to said input gear of said differential gear means, said axle assembly further having an axle housing comprising an upper casing half and a lower casing half, said casing halves being joined together on a first plane containing an axis of rotation of said first and second axle shafts and being operable to journal said axle shafts therebetween; characterized by: (a) said hydrostatic transmission further including a transmission case comprising a first case portion and a second case portion, said case portions being joined together on a second plane oriented generally perpendicular to an axis of rotation defined by said output means; (b) said second case portion including an output hub portion surrounding said output means; (c) said axle housing casing halves including an input portion in cooperative engagement about said output hub portion of said second case portion; (d) another portion of said transmission case cooperating with a portion of at least one of said axle casing halves to define a secondary mounting means and a torque reaction means; and (e) said output hub portion, said secondary mounting means, and said torque reaction means comprising the only portions of said transmission case fixedly secured with said axle housing.
Claim 2
Dependent Claim 282 words
A hydrostatic transaxle of the type including a hydrostatic transmission having an input means, a hydrostatic pump driven by said input means, a hydrostatic motor, and an output means driven by said motor; and an axle assembly having a differential gear means including an input gear and first and second output gears, first and second axle shafts driven by said first and second output gears, respectively, and an output gear train operable to transmit torque from said output means of said hydrostatic transmission to said input gear of said differential gear means, said axle assembly further having an axle housing comprising an upper casing half and a lower casing half, said casing halves being joined together on a first plane containing an axis of rotation of said first and second axle shafts and being operable to journal said axle shafts therebetween; characterized by: (a) said hydrostatic transmission further including a transmission case comprising a first case portion and a second case portion, said case portions being joined together on a second plane oriented generally perpendicular to an axis of rotation defined by said output means; (b) said second case portion including an output hub portion surrounding said output means; (c) said axle housing casing halves including an input portion in cooperative engagement about said output hub portion of said second case portion; (d) another portion of said transmission case cooperating with a portion of at least one of said axle casing halves to define a secondary mounting means and a torque reaction means; and (e) said output hub portion, said secondary mounting means, and said torque reaction means comprising the only portions of said transmission case fixedly secured with said axle housing.
Claim 3
Dependent Claim 37 words
A hydrostatic transaxle as claimed in claim 1, characterized by output seal means disposed between said output means and said output hub portion, said output seal means being operable to retain hydraulic fluid within said transmission case.
Claim 4
Dependent Claim 69 words
A hydrostatic transaxle as claimed in claim 1, characterized by said transmission case including said torque reaction means being formed integrally therewith and oriented generally parallel to said axis of rotation of said first and second axle shafts, said torque reaction means being disposed parallel to one of said axle housing upper and lower casing halves to prevent rotation of said hydrostatic transmission case, relative to said axle housing.
Claim 5
Dependent Claim 80 words
A hydrostatic transaxle as claimed in claim 1, characterized by an output gear train being disposed within said axle housing, and in operable engagement with said output means of said hydrostatic transmission, said output gear train including at least one gear shaft in operable engagement with said output means, and oriented generally parallel to said axis of rotation of said first and second axle shafts, said axle housing upper and lower casing halves being operable to journal said gear shaft.
Claim 6
Dependent Claim 46 words
A hydrostatic transaxle as claimed in claim 1, characterized by substantially every element disposed within said axle housing having an axis and being symmetrical about said axis, said axis lying on said second plane containing said axes of rotation of said first and second axle shafts.
Claim 7
Dependent Claim 48 words
A hydrostatic transaxle as claimed in claim 1, characterized by said output hub portion defining a taper, whereby the outside diameter of said output hub portion decreases in a direction extending away from said hydrostatic motor, said input portion of said axle housing halves defining a corresponding taper.
Claim 8
Dependent Claim 236 words
A hydrostatic transaxle of the type including a hydrostatic transmission comprising a fluid pump including input means and a fluid motor including output means; an axle assembly having a differential gear means operable to transmit drive torque to first and second axle shafts; an output gear train operable to transmit torque from said output means of said fluid motor to said differential gear means; said axle assembly further having an axle housing comprising an upper casing half and a lower casing half, said casing halves being joined together on a plane containing an axis of rotation of said first and second axle shafts and being operable to journal said axle shafts therebetween; characterized by: (a) said input means of said fluid pump and said output means of said fluid motor defining a common axis of rotation; (b) said hydrostatic transmission further including a transmission case comprising a first case portion and a second case portion, said case portions being joined together on a plane oriented generally perpendicular to said common axis of rotation; (c) said first case portion including an input hub portion and said second case portion including an output hub portion, said hub portions being disposed at opposite axial ends of said hydrostatic transmission; (d) said axle housing casing halves including an input portion in cooperative engagement about said input hub portion, and an output portion in cooperative engagement about said output hub portion.
Claim 9
Dependent Claim 236 words
A hydrostatic transaxle of the type including a hydrostatic transmission comprising a fluid pump including input means and a fluid motor including output means; an axle assembly having a differential gear means operable to transmit drive torque to first and second axle shafts; an output gear train operable to transmit torque from said output means of said fluid motor to said differential gear means; said axle assembly further having an axle housing comprising an upper casing half and a lower casing half, said casing halves being joined together on a plane containing an axis of rotation of said first and second axle shafts and being operable to journal said axle shafts therebetween; characterized by: (a) said input means of said fluid pump and said output means of said fluid motor defining a common axis of rotation; (b) said hydrostatic transmission further including a transmission case comprising a first case portion and a second case portion, said case portions being joined together on a plane oriented generally perpendicular to said common axis of rotation; (c) said first case portion including an input hub portion and said second case portion including an output hub portion, said hub portions being disposed at opposite axial ends of said hydrostatic transmission; (d) said axle housing casing halves including an input portion in cooperative engagement about said input hub portion, and an output portion in cooperative engagement about said output hub portion.
Claim 10
Dependent Claim 49 words
A hydrostatic transaxle as claimed in claim 7, characterized by said transmission case including a portion operably associated with at least one of said axle casing halves to provide a torque reaction means, operable to resist rotational torque acting on said hydrostatic transmission, about said common axis of rotation.
Claim 11
Dependent Claim 37 words
A hydrostatic transaxle as claimed in claim 8, characterized by said input hub portion, said output hub portion, and said torque reaction portion comprising the only portions of said transmission case fixedly secured with said axle housing.
Claim 12
Dependent Claim 39 words
A hydrostatic transaxle as claimed in claim 7, characterized by substantially every element disposed within said axle housing being symmetrical about an axis lying on said plane containing said axes of rotation of said first and second axle shafts.
Claim 13
Dependent Claim 64 words
A hydrostatic transaxle as claimed in claim 7, characterized by said input hub portion and said output hub portion each defining a taper, whereby the outside diameters of said hub portions decreases in a direction extending axially away from said fluid pump and said fluid motor, respectively; said input portion and said output portion defined by said axle housing casing halves defining corresponding tapers.
Claim 14
Dependent Claim 257 words
A hydrostatic transaxle of the type including a hydrostatic transmission having an input means, a hydrostatic pump driven by said input means, a hydrostatic motor, and an output means driven by said motor; and an axle assembly having a differential gear means including an input gear and first and second output gears, first and second axle shafts driven by said first and second output gears, respectively, and an output gear train operable to transmit torque from said output means of said hydrostatic transmission to said input gear of said differential gear means, said axle assembly further having an axle housing comprising an upper casing half and a lower casing half, said casing halves being joined together on a plane containing an axis of rotation of said first and second axle shafts and being operable to journal said axle shafts therebetween; characterized by: (a) said hydrostatic transmission further including a transmission case comprising a first case portion and a second case portion, said case portions being joined together on a plane oriented generally perpendicular to an axis of rotation defined by said output means; (b) said axle housing casing halves including a receiving portion disposed to surround said output means of said hydrostatic transmission; (c) another portion of said transmission case cooperating with at least one portion of said axle casing halves to define mounting means and a torque reaction means; and (d) said output means, said mounting means and said torque reaction means comprising the only portions of said transmission case fixedly secured to said axle housing.
Claim 15
Dependent Claim 257 words
A hydrostatic transaxle of the type including a hydrostatic transmission having an input means, a hydrostatic pump driven by said input means, a hydrostatic motor, and an output means driven by said motor; and an axle assembly having a differential gear means including an input gear and first and second output gears, first and second axle shafts driven by said first and second output gears, respectively, and an output gear train operable to transmit torque from said output means of said hydrostatic transmission to said input gear of said differential gear means, said axle assembly further having an axle housing comprising an upper casing half and a lower casing half, said casing halves being joined together on a plane containing an axis of rotation of said first and second axle shafts and being operable to journal said axle shafts therebetween; characterized by: (a) said hydrostatic transmission further including a transmission case comprising a first case portion and a second case portion, said case portions being joined together on a plane oriented generally perpendicular to an axis of rotation defined by said output means; (b) said axle housing casing halves including a receiving portion disposed to surround said output means of said hydrostatic transmission; (c) another portion of said transmission case cooperating with at least one portion of said axle casing halves to define mounting means and a torque reaction means; and (d) said output means, said mounting means and said torque reaction means comprising the only portions of said transmission case fixedly secured to said axle housing.
Claim 16
Dependent Claim 28 words
A hydrostatic transaxle as claimed in claim 12, characterized by said output means comprising the only location of said hydrostatic transmission surrounded by said axle housing casing halves.
Claim 17
Dependent Claim 41 words
A hydrostatic transaxle as claimed in claim 12, characterized by said second case portion including an output hub portion surrounding said output means and defining a generally cylindrical pilot surface piloted within said receiving portion of said axle housing casing halves.
Claim 18
Dependent Claim 264 words
A hydrostatic transaxle of the type including a hydrostatic transmission having an input means, a hydrostatic pump driven by said input means, a hydrostatic motor, and an output means driven by said motor; and an axle assembly having a differential gear means including an input gear and first and second output gears, first and second axle shafts driven by said first and second output gears, respectively, and an output gear train operable to transmit torque from said output means of said hydrostatic transmission to said input gear of said differential gear means, said axle assembly further having an axle housing comprising an upper casing half and a lower casing half, said casing halves being joined together on a plane containing an axis of rotation of said first and second axle shafts and being operable to journal said axle shafts therebetween; characterized by: (a) said hydrostatic transmission further including a transmission case comprising a first case portion and a second case portion, said case portions being joined together to define a main transmission case, and output hub portion, and at least one mounting portion extending radially outwardly from said main transmission case portion; (b) said axle housing casing halves including a receiving portion disposed to surround said output means of said hydrostatic transmission, and a mounting means in fixed engagement with said mounting portion of said transmission case; and (c) said surrounding relationship of said receiving portion and said output means, and said engagement of said mounting means and said mounting portion comprising substantially the only engagement of said transmission case and said axle housing.
Claim 19
Dependent Claim 264 words
A hydrostatic transaxle of the type including a hydrostatic transmission having an input means, a hydrostatic pump driven by said input means, a hydrostatic motor, and an output means driven by said motor; and an axle assembly having a differential gear means including an input gear and first and second output gears, first and second axle shafts driven by said first and second output gears, respectively, and an output gear train operable to transmit torque from said output means of said hydrostatic transmission to said input gear of said differential gear means, said axle assembly further having an axle housing comprising an upper casing half and a lower casing half, said casing halves being joined together on a plane containing an axis of rotation of said first and second axle shafts and being operable to journal said axle shafts therebetween; characterized by: (a) said hydrostatic transmission further including a transmission case comprising a first case portion and a second case portion, said case portions being joined together to define a main transmission case, and output hub portion, and at least one mounting portion extending radially outwardly from said main transmission case portion; (b) said axle housing casing halves including a receiving portion disposed to surround said output means of said hydrostatic transmission, and a mounting means in fixed engagement with said mounting portion of said transmission case; and (c) said surrounding relationship of said receiving portion and said output means, and said engagement of said mounting means and said mounting portion comprising substantially the only engagement of said transmission case and said axle housing.
Claim 20
Dependent Claim 24 words
A hydrostatic transaxle as claimed in claim 15, characterized by said main transmission case portion being disposed out of contact with said axle housing.
Claim 21
Dependent Claim 36 words
A hydrostatic transaxle as claimed in claim 15, characterized by said output hub portion surrounding said output means and defining a generally cylindrical pilot surface piloted within said receiving portion of said axle housing casing halves.
Claim 22
Dependent Claim 39 words
A hydrostatic transaxle as claimed in claim 15, characterized by said receiving portion defined by said axle housing casing halves being disposed in cooperative engagement with said output hub portion defined by said first and second transmission case portions.

References Cited (Backward Citations)

US3902567A Cited
US4726256A Cited
US4756208A Cited
US4870820A Cited
US4856368A Cited
US4979583A Cited
US4893524A Cited
US4891943A Cited
US4905472A Cited
US4986073A Cited
US4953426A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-02-28 1997-08-30 1998-03-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-02-28 2001-08-30 2002-03-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-02-28 2005-08-30 2006-03-01 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag