Patent US3760918A successfully refreshed from Google Patents.
US3760918A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tractor pto and propulsion clutch assembly including lubrication means
Assignee: Deere and Co
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Filing: 1972-04-20
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Granted: 1973-09-25
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Expires: 1992-04-20
Abstract
Abstract A tractor transmission includes a hollow PTO input drive shaft having a propulsion input drive shaft located therein, the ends of the shafts terminating adjacent an engine flywheel and carrying PTO and propulsion clutch elements for selectively fixing one or the other or both of the shafts to the flywheel for rotation therewith. The clutch elements are respectively actuated into engagement with a backing plate carried by the flywheel by means of a pair of concentrically arranged fluid-operated pistons. A pilot-operated clutch-lubrication-fluid control valve shifts in response to the operating pressure acting on the pistons to block the flow of fluid to the clutches when both clutches are disengaged, to permit a predetermined amount of fluid to flow to both clutches when both or only the propulsion clutch is engaged and to permit a lesser amount of fluid than said predetermined amount to flow toward the clutches when only the PTO clutch is engaged. A restriction is located in the lubrication fluid passage between the connection of the passage with the PTO and propulsion clutches and the restriction acts to cause substantially all of the lesser amount of fluid to flow to the PTO clutch when only the PTO clutch is engaged.
Inventors
- 👤 W Weissenfluh
- 👤 P Wetrich
- 👤 L Madson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:58
CPC Classifications
F; F16; F16D; F16D21/00; F16D21/02; F16D21/06; F16D25/00; F16D25/08; F16D25/082; F16D25/10; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/86493; Y10T137/86574; Y10T137/86582
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
370 words
In an agricultural tractor of the type including an engine flywheel having a clutch backing plate means secured thereto for rotation therewith, traction wheel and power take-off drive means respectively including first and second concentrically arranged input drive shafts disposed coaxially with said flywheel and having ends terminating in the vicinity of the backing plate means, first and second clutch members respectively fixed for rotation with the first and second input drive shafts, the first and second clutch members respectively including friction disc elements axially shiftably mounted for engagement and disengagement with the opposite axial faces of the backing plate means, first and second pressure plate means respectively mounted for rotation with and for axial movement relative to said flywheel at respective positions confronting the faces of the disc elements remote from the backing plate means; first and second sets of levers connected for selectively moving the first and second pressure plate means axially in opposite directions when the levers are moved in a common direction; the improvement comprising: a pair of concentric annular hydraulic pistons disposed concentrically about the first and second drive input shafts; said first and second sets of levers being respectively located in the path of movement of the pair of pistons; spring means normally biasing said pressure plate means away from engagement with the backing plate; hydraulic control means for selectively actuating one or the other or both of the pair of pistons for respectively effecting engagement of one or the other or both of the pressure plate means respectively with one or the other of the friction disc means to engage the latter with a respective side of the backing plate; and a source of lubrication fluid; passage means fluid-connecting said source to the opposed faces of the friction disc means and the backing and pressure plate means; pressure responsive valve means interposed in said passage means and responsive to the respective operating pressures of said pair of pistons for blocking the flow of lubrication oil to said clutch members when both pistons are deactivated and for permitting the flow of lubrication oil to the opposed faces of the friction disc means and the backing and pressure plate means when both pistons are activated.
Claim 2
Dependent Claim
370 words
In an agricultural tractor of the type including an engine flywheel having a clutch backing plate means secured thereto for rotation therewith, traction wheel and power take-off drive means respectively including first and second concentrically arranged input drive shafts disposed coaxially with said flywheel and having ends terminating in the vicinity of the backing plate means, first and second clutch members respectively fixed for rotation with the first and second input drive shafts, the first and second clutch members respectively including friction disc elements axially shiftably mounted for engagement and disengagement with the opposite axial faces of the backing plate means, first and second pressure plate means respectively mounted for rotation with and for axial movement relative to said flywheel at respective positions confronting the faces of the disc elements remote from the backing plate means; first and second sets of levers connected for selectively moving the first and second pressure plate means axially in opposite directions when the levers are moved in a common direction; the improvement comprising: a pair of concentric annular hydraulic pistons disposed concentrically about the first and second drive input shafts; said first and second sets of levers being respectively located in the path of movement of the pair of pistons; spring means normally biasing said pressure plate means away from engagement with the backing plate; hydraulic control means for selectively actuating one or the other or both of the pair of pistons for respectively effecting engagement of one or the other or both of the pressure plate means respectively with one or the other of the friction disc means to engage the latter with a respective side of the backing plate; and a source of lubrication fluid; passage means fluid-connecting said source to the opposed faces of the friction disc means and the backing and pressure plate means; pressure responsive valve means interposed in said passage means and responsive to the respective operating pressures of said pair of pistons for blocking the flow of lubrication oil to said clutch members when both pistons are deactivated and for permitting the flow of lubrication oil to the opposed faces of the friction disc means and the backing and pressure plate means when both pistons are activated.
Claim 3
Dependent Claim
76 words
The invention defined in claim 1 wherein said valve means further includes means for directing a preselected limited flow of lubrication fluid to said passage means when only the piston for operating the second set of levers is activated; and said passage means including flow restriction means for directing substantially the entire amount of said limited flow to the opposed faces of said second friction disc element, said second pressure plate means and said backing plate.
Claim 4
Dependent Claim
214 words
The invention defined in claim 2 wherein the first input drive shaft is located interiorly of said second input drive shaft; said first and second clutch members respectively having hubs splined to said first and second input drive shafts; said fluid passage means including: a first space between said first and second input drive shafts and a second space between the hub of the second clutch member and the second input drive shaft, the spaces being interconnected by opening means extending through the second input drive shaft; said second space including first and second enlarged portions interconnected by a restricted passage, said first enlarged portion being upstream from said second enlarged portion; said first and second enlarged portions being respectively connected to first and second radial passage means leading respectively to the friction disc elements of the second clutch member and friction disc elements of the first clutch member; and said restricted passage being sized such that when said valve means is directing said preselected limited flow of fluid to the passage means, as when only the second clutch member is engaged, substantially all of the flow is blocked from the second enlarged portion and caused to flow through said first radial passage means to said friction disc element of the second clutch member.
Claim 5
Dependent Claim
292 words
A tractor transmission assembly, comprising: a powered shaft having clutch backing plate means secured thereto for rotation therewith; traction wheel and power take-off drive means respectively including first and second drive input shafts disposed coaxially with said powered shaft and having ends terminating in the vicinity of the backing plate means, first and second clutch members respectively fixed for rotation with said first and second drive input shafts and respectively including first and second axially shiftable friction disc elements disposed for engagement with the backing plate means; control means including first and second hydraulic actuator means for selectively engaging and disengaging said first and second friction disc elements with said backing plate means for establishing a driving connection between the powered shaft and one or the other or both of the traction wheels and power take-off drive means, the improvement comprising: said first and second friction disc elements being oil cooled; supplying means for providing cooling oil including first and second pilot lines respectively connected to the first and second hydraulic actuator means to monitor the clutch activating pressure thereat; a source of fluid pressure, a cooling oil direction control valve means including a valve bore connected to the source of fluid pressure, the sump and the first and second pilot lines; fluid passage means connecting said valve bore to said first and second friction disc elements to provide cooling oil to the latter; and pressure responsive valve member means shiftably mounted in said bore for blocking the flow of fluid from the source of fluid pressure to the first and second friction disc elements when both hydraulic actuator means are depressurized and for connecting the source of fluid pressure to the friction disc elements when both hydraulic actuator means are pressurized.
Claim 6
Dependent Claim
292 words
A tractor transmission assembly, comprising: a powered shaft having clutch backing plate means secured thereto for rotation therewith; traction wheel and power take-off drive means respectively including first and second drive input shafts disposed coaxially with said powered shaft and having ends terminating in the vicinity of the backing plate means, first and second clutch members respectively fixed for rotation with said first and second drive input shafts and respectively including first and second axially shiftable friction disc elements disposed for engagement with the backing plate means; control means including first and second hydraulic actuator means for selectively engaging and disengaging said first and second friction disc elements with said backing plate means for establishing a driving connection between the powered shaft and one or the other or both of the traction wheels and power take-off drive means, the improvement comprising: said first and second friction disc elements being oil cooled; supplying means for providing cooling oil including first and second pilot lines respectively connected to the first and second hydraulic actuator means to monitor the clutch activating pressure thereat; a source of fluid pressure, a cooling oil direction control valve means including a valve bore connected to the source of fluid pressure, the sump and the first and second pilot lines; fluid passage means connecting said valve bore to said first and second friction disc elements to provide cooling oil to the latter; and pressure responsive valve member means shiftably mounted in said bore for blocking the flow of fluid from the source of fluid pressure to the first and second friction disc elements when both hydraulic actuator means are depressurized and for connecting the source of fluid pressure to the friction disc elements when both hydraulic actuator means are pressurized.
Claim 7
Dependent Claim
68 words
The invention defined in claim 4 wherein said valve member means includes means for directing a flow of fluid no greater than a preselected limited flow of lubrication fluid to said fluid passage means when only the second hydraulic actuator means is being pressurized; and said passage means including flow restriction means for directing substantially the entire amount of said limited flow to the second friction disc elements.
Claim 8
Dependent Claim
147 words
The invention defined in claim 4 wherein said valve member means includes a spool member having opposite first and second ends; a stop means being located in said bore in the path of movement of said first end; biasing means acting on said second end and normally positioning said spool member in a first position, against said stop means, wherein said source of fluid pressure is blocked from fluid communication with said fluid passage means; said first pilot line being connected to said bore in direct communication with said first end of the spool member; and said spool member being shiftable away from the stop means against said biasing means, in response to fluid pressure in said first pilot line, to a second position wherein flow greater than a preselected limited amount of flow is permitted between said source of fluid pressure and said fluid passage means.
Claim 9
Dependent Claim
255 words
The invention defined in claim 6 wherein said second pilot line is connected to said bore at a location spaced axially both from the first end of the spool member and the location whereat the first pilot line connects to the bore; a pilot pin being axially shiftably mounted in the bore between, and preventing fluid flow between the locations whereat the first and second pilot lines are connected to the bore; said pilot pin having one end positioned for contacting the first end of the spool member and having an opposite end in fluid communication with the second pilot line; said pilot pin being shiftable against said spool member for moving the latter against said biasing means in response to fluid pressure in said sEcond pilot line; second stop means located in said bore in the path of movement of said pilot pin in the direction of the spool member, the stop means being positioned to contact the one end of the pilot pin after the valve member is shifted to an intermediate position between said first and second positions, permitting flow no greater than said preselected limited amount of flow to occur between said source of fluid pressure and the fluid passage means; and fluid restriction means being positioned in said fluid passage means between said first and second friction disc elements for permitting flow to said first friction disc elements only when the flow from the source of fluid pressure to the fluid passage means is greater than said preselected limited amount.
Claim 10
Dependent Claim
31 words
The invention defined in claim 7 wherein the first-mentioned stop means and said second stop means are defined by the opposite sides of a stop pin fixed transversely in the bore.
Claim 11
Dependent Claim
210 words
The invention defined in claim 4 wherein the first input drive shaft is located concentric with and interiorly of said second input drive shaft; said first and second clutch members including respective hubs splined to said first and second input drive shafts; said fluid passage means including: a first space between said first and second input drive shafts and a second space between the hub of the second clutch member and the second input drive shaft, the spaces being interconnected by opening means extending through the second input drive shaft; said second space including first and second enlarged portions interconnected by a restricted passage, said first enlarged portion being upstream from said second enlarged portion; said first and second enlarged portions being respectively connected to first and second radial passage means leading to the friction disc elements of the second and first clutch members; said restricted passage means being sized such that substantially all flow below a preselected minimum flow will be directed to the friction disc elements of said second clutch member; and said valve member means including means for directing a flow of fluid no greater than said preselected limited flow of fluid, to said fluid passage means when only the second hydraulic actuator means is being pressurized.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-24 | 1977-03-26 | 1977-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-24 | 1981-03-26 | 1981-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-24 | 1985-03-26 | 1985-09-25 | $7700.00 | Window Closed / Lapsed |