US3667309A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multi speed drive transmission
Assignee: Caterpillar Inc
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Filing: 1970-10-14
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Granted: 1972-06-06
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Expires: 1990-10-14
Abstract
Abstract A drive transmission for powered vehicles and the like has change speed gears which may be shifted to provide a selected one of a plurality of drive ratios and has clutches at both the input and output ends whereby the gears may be decoupled from both the driving engine and driven shaft and may then be braked to a stop to facilitate shifting. Brakes are provided at both the input and output ends of the gearing section and a pneumatic control system responds to movement of the operator''s shift lever by operating the clutches and brakes in a programmed sequence which assures smooth shifting and avoids damage. Upon movement of the operator''s shift lever to a selected setting, the control system simultaneously disengages both clutches and applies both brakes. The control system then energizes fluid operated means for making the appropriate gear interconnections and then sequentially releases the input brake and the output brake. The input clutch is then engaged and finally the output clutch is engaged to reestablish a driving connection between the engine and driven elements. The delay between release of the input and output brakes assures that abutted teeth in the gearing section engage easily at low relative speeds and under only light loading.
Inventors
- 👤 Maurice F Franz
- 👤 Charles H Herr
- 👤 Harry B Newman
- 👤 Philip S Webber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 14:28
CPC Classifications
F; F16; F16H; F16H3/00; F16H3/02; F16H3/08; F16H3/087; F16H3/093; F16H3/097; F16H61/00; F16H61/04; F16H61/0403; F16H61/70; F16H61/705; F16H2003/0803; F16H2061/0411; F16H2061/047; F16H2200/00; F16H2200/003; F16H2200/0065; F16H2200/0082; F16H2200/0086; F16H2306/00; F16H2306/40; F16H2306/44; F16H2306/46; F16H2306/48; F16H2306/50; F16H2306/52; F16H61/08; F16H61/68; F16H61/682; Y; Y10; Y10T; Y10T74/00; Y10T74/19; Y10T74/19219; Y10T74/19284; Y10T74/19288
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
220 words
A drive transmission for coupling an engine to a driven load at any selected one of a plurality of drive ratios comprising: a gear section having an input shaft and an output shaft and a plurality of change speed gears and having shift means for interconnecting said gears in any of a plurality of predetermined relationships to provide said plurality of drive ratios, an input clutch for coupling said gear section input shaft to said engine and having an engaged position and a disengaged position, an input brake operative on said gear section input shaft and having an engaged position and a disengaged position, an output clutch for coupling said driven load and said gear section output shaft and having an engaged position and a disengaged position, an output brake operative on said gear section output shaft and having an engaged position and a disengaged position, an operator''s shift initiating element movable between a plurality of positions each corresponding to a separate one of said drive ratios, and shift control means initiating disengagement of said input and output clutches and engagement of said input and output brakes in response to movement of said shift initiating element to any of said positions thereof and subsequently initiating disengagement of said input and output brakes and engagement of said input and output clutches.
Claim 2
Dependent Claim
220 words
A drive transmission for coupling an engine to a driven load at any selected one of a plurality of drive ratios comprising: a gear section having an input shaft and an output shaft and a plurality of change speed gears and having shift means for interconnecting said gears in any of a plurality of predetermined relationships to provide said plurality of drive ratios, an input clutch for coupling said gear section input shaft to said engine and having an engaged position and a disengaged position, an input brake operative on said gear section input shaft and having an engaged position and a disengaged position, an output clutch for coupling said driven load and said gear section output shaft and having an engaged position and a disengaged position, an output brake operative on said gear section output shaft and having an engaged position and a disengaged position, an operator''s shift initiating element movable between a plurality of positions each corresponding to a separate one of said drive ratios, and shift control means initiating disengagement of said input and output clutches and engagement of said input and output brakes in response to movement of said shift initiating element to any of said positions thereof and subsequently initiating disengagement of said input and output brakes and engagement of said input and output clutches.
Claim 3
Dependent Claim
37 words
The combination defined in claim 1 wherein said shift control means delays engagement of one of said brakes relative to the other thereof following said movement of said shift initiating element into one of said positions thereof.
Claim 4
Dependent Claim
28 words
The combination defined in claim 1 wherein said shift control means includes delay means which delays disengagement of said output brake relative to disengagement of said input brake.
Claim 5
Dependent Claim
60 words
The combination defined in claim 1 wherein said shift control means responds to said movement of shift initiating element into one of said positions thereof by disengaging said clutches and engaging said brakes, operating said shift means and sequentially disengaging said front brake and then disengaging said rear brake, then engaging said front clutch, and then engaging said rear clutch.
Claim 6
Dependent Claim
119 words
The combination defined in claim 1 wherein said input brake and said output brake are fluid pressure operated and wherein said shift control means comprises an input brake valve for supplying fluid under pressure to said input brake, an output brake valve for supplying fluid under pressure to said output brake, and sequencing means responding to said movement of said shift initiating element into one of said positions thereof by operating said input brake valve and subsequently operating said output brake valve whereby said input brake is disengaged prior to disengagement of said output brake to provide for rotation of said gear section input shaft while said output shaft thereof is braked to facilitate engagement of said gears therein.
Claim 7
Dependent Claim
204 words
The combination defined in claim 1 wherein each of said clutches and brakes are controlled by fluid pressure and wherein said shift control means comprises an input clutch control valve for supplying pressurized fluid to said input clutch, an input brake control valve for supplying pressurized fluid to aid input brake, an output clutch control valve for supplying pressurized fluid to said output clutch, an output brake control valve for supplying pressurized fluid to said output brake and fluid pressure sequencing means which responds to said movement of said shift initiating element into one of said positions thereof by first operating said input clutch valve and said output clutch valve to disengage said input and output clutches and then subsequently operates said input and output brake valves to engage said input and output brakes, and then subsequently operates said shift means of said gear section, and then subsequently operates said input brake valve to disengage said input brake, and then subsequently operates said output brake valve to disengage said output brake and then subsequently operates said input clutch valve to reengage said input clutch, and then subsequently operates said output clutch valve to reengage said output clutch to restore torque transmission through said transmission.
Claim 8
Dependent Claim
249 words
The combination defined in claim 1 wherein said output clutch and said output brake are contained within an output coupler section of said transmission between said gear section and said driven load, said output coupler section comprising: a housing, having said gear section output shaft extending therein and having a driven member extending therein in coaxial relationship to said gear section output member, a first output clutch disc disposed in said housing and being splined to said gear section output shaft for rotation therewith, a second output clutch disc disposed in said housing adjacent said first clutch disc and being splined to said driven member for rotation therewith, a pressure plate in said housing splined To said gear section output shaft for rotation therewith, said pressure plate being movable axially to compress said first clutch disc against said second clutch disc whereby said gear section output shaft is drivingly coupled to said driven member, a spring bearing against said pressure plate in a direction tending to relieve the pressure of said plate against said clutch disc, an output clutch piston in said housing movable to exert force against said pressure plate in opposition to the force of said spring thereon to cause said pressure plate to engage said clutch disc, means for directing fluid pressure to said output clutch piston for producing said movement thereof, and a braking means in said housing for exerting a clamping force on said gear section output shaft while said clutch discs are disengaged.
Claim 9
Dependent Claim
95 words
The combination defined in claim 7 wherein said braking means comprises a first brake disc splined to said gear section output shaft for rotation therewith and being movable axially relative thereto, a second brake disc disposed adjacent said first brake disc and being fixed against rotation relative to said housing, and an output brake piston disposed in said housing and being movable to force said first brake disc against said second brake disc, and means for applying fluid pressure to said second piston for selectively causing said output brake piston to engage said brake discs.
Claim 10
Dependent Claim
218 words
An output coupler mechanism for a drive transmission having change speed gearing comprising: a housing, rotatable drive means extending into said housing for transmitting drive from said change speed gearing, rotatable driven means extending out of said housing, a first clutch disc disposed in said housing and being splined to said drive means for rotation therewith, a second clutch disc disposed in said housing adjacent said first clutch disc and being splined to said driven means for rotation therewith, a pressure plate in said housing splined to said drive means for rotation therewith, said pressure plate being movable axially to compress said first clutch disc against said second clutch disc whereby said drive means is drivingly coupled to said driven means, a spring bearing against said pressure plate in a direction tending to relieve the pressure of said plate against said clutch disc, a clutch piston in said housing movable to exert a force against said pressure plate in opposition to the force of said spring thereon to cause said pressure plate to engage said clutch discs, means for selectively and controllably applying fluid pressure to said clutch piston for producing said movement thereof, and means for braking said drive member while said clutch discs are disengaged whereby said change speed gearing is stopped to facilitate shifting thereof.
Claim 11
Dependent Claim
218 words
An output coupler mechanism for a drive transmission having change speed gearing comprising: a housing, rotatable drive means extending into said housing for transmitting drive from said change speed gearing, rotatable driven means extending out of said housing, a first clutch disc disposed in said housing and being splined to said drive means for rotation therewith, a second clutch disc disposed in said housing adjacent said first clutch disc and being splined to said driven means for rotation therewith, a pressure plate in said housing splined to said drive means for rotation therewith, said pressure plate being movable axially to compress said first clutch disc against said second clutch disc whereby said drive means is drivingly coupled to said driven means, a spring bearing against said pressure plate in a direction tending to relieve the pressure of said plate against said clutch disc, a clutch piston in said housing movable to exert a force against said pressure plate in opposition to the force of said spring thereon to cause said pressure plate to engage said clutch discs, means for selectively and controllably applying fluid pressure to said clutch piston for producing said movement thereof, and means for braking said drive member while said clutch discs are disengaged whereby said change speed gearing is stopped to facilitate shifting thereof.
Claim 12
Dependent Claim
64 words
The combination defined in claim 9 wherein said drive means and driven means and said clutch discs and said pressure plate and said clutch piston are coaxial annular elements and further comprising means for constraining said clutch piston against rotation and bearing means disposed between said clutch piston and said pressure plate for transmitting axial movement of said clutch piston to said pressure plate.
Claim 13
Dependent Claim
61 words
The combination defined in claim 10 wherein said driven means comprises an output shaft and an output member splined thereto, and a tapered roller thrust bearing disposed coaxially between said output member and said stationary housing whereby the force of said clutch piston against said pressure plate and said clutch disc is sustained by said bearing rather than said output shaft.
Claim 14
Dependent Claim
93 words
The combination defined in claim 9 wherein said means for braking said drive means comprises a first brake disc splined to said drive means for rotation therewith and being movable axially relative thereto, a second brake disc disposed adjacent said first brake disc and being fixed against rotation relative to said housing, a brake piston disposed in said housing and being movablE to compress said first brake disc against said second brake disc, and means for applying fluid pressure to said brake piston for selectively causing said piston to compress said brake discs.
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) | 1975-06-06 | 1975-12-06 | 1976-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-06 | 1979-12-06 | 1980-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-06 | 1983-12-06 | 1984-06-06 | $7700.00 | Window Closed / Lapsed |