EP0045922A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Automatic transaxle control system
Assignee: Ford-Werke GmbH
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Filing: 1981-08-01
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Granted: —
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Expires: 2001-08-01
Abstract
Abstract An automatic control system for a multiple ratio power transmission mechanism having a hydrokinetic torque converter (12) and multiple ratio gearing (32), the speed ratio of which is controlled by selectively engageable clutches (Cl 1 , Cl 2 , und C1 3 ) and brakes (B,) the control system including a timing valve circuit (302, 322) that is effective to establish optimum timing between the clutch (Cl 1 ,) and brake (B 1 ) engagement and release pattern during ratio changes at various driving torques and at various magnitudes of transmission throttle valve pressures, the latter being an indicator of the operator's demand for driving torque.
Inventors
- 👤 Douglas A. Whitney
- 👤 Sergio Kavalhuna
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 11:08
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/04; F16H61/06; F16H61/065; F16H61/02; F16H61/0262; F16H61/0265; F16H61/0267; F16H61/068; F16H61/08; F16H61/10
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
413 words
A control system for an automatic transmission mechanism comprising : planetary gear elements adapted to provide multiple speed ratios as torque is transferred therethrough from a driving member to a driven member ; clutch means (Cl 1 and Cl 2 ) for connecting together two of said gear elements (S 3 and R 2 ) for rotation in unison to establish a high speed ratio of unity ; brake means (B 1 ) for anchoring one of said gear elements (S 2 ) to establish an underdrive speed ratio, said brake means (B 1 ) including a double acting servo (58) with a piston having a pressure apply area and a pressure release area, friction brake means connected to said piston and energized thereby when said pressure apply area is pressurized ; a pressure source (70) ; conduit structure connecting said pressure source (70) to said clutch means(Cl and Cl 2 ) and to said servo (58) including portions communicating with each of said piston areas ; shift valve means (142 and 144) in said conduit structure for controlling pressure distribution to said clutch and brake means ; throttle valve means (1 0 6) for developing a pressure signal proportional to torque on said driving member ; governor valve means (100) for developing a pressure signal proportional to the speed of said driven member ; multiple position manual valve means (80) in said conduit structure for distributing pressure selectively to different regions of said conduit structure whereby said control system is conditioned for automatic ratio changes between said direct drive and underdrive ratios when it assumes one position and whereby operation in said direct drive range is prevented when it assumes a second position characterized in that, said shift valve means (142 and 144) being subjected to said throttle pressure signal and said governor pressure signal which establish opposed forces thereon ; a shift modulator valve means (214) between siad throttle valve means (106) and said shift valve means (144) for establishing a downshifting force on the latter which effects a desired upshift point upon increases in said speed signal ; and a downshift control valve means (280) communicating with said clutch means (C1 2 ) and said shift modulator valve means (214) for developing a modulated pressure signal that affects the modulating action of the shift modulator valve means (214) to effect a desired downshift point that is independent of the speed at which an upshift occurs for any given throttle pressure.
Claim 2
Dependent Claim
413 words
A control system for an automatic transmission mechanism comprising : planetary gear elements adapted to provide multiple speed ratios as torque is transferred therethrough from a driving member to a driven member ; clutch means (Cl 1 and Cl 2 ) for connecting together two of said gear elements (S 3 and R 2 ) for rotation in unison to establish a high speed ratio of unity ; brake means (B 1 ) for anchoring one of said gear elements (S 2 ) to establish an underdrive speed ratio, said brake means (B 1 ) including a double acting servo (58) with a piston having a pressure apply area and a pressure release area, friction brake means connected to said piston and energized thereby when said pressure apply area is pressurized ; a pressure source (70) ; conduit structure connecting said pressure source (70) to said clutch means(Cl and Cl 2 ) and to said servo (58) including portions communicating with each of said piston areas ; shift valve means (142 and 144) in said conduit structure for controlling pressure distribution to said clutch and brake means ; throttle valve means (1 0 6) for developing a pressure signal proportional to torque on said driving member ; governor valve means (100) for developing a pressure signal proportional to the speed of said driven member ; multiple position manual valve means (80) in said conduit structure for distributing pressure selectively to different regions of said conduit structure whereby said control system is conditioned for automatic ratio changes between said direct drive and underdrive ratios when it assumes one position and whereby operation in said direct drive range is prevented when it assumes a second position characterized in that, said shift valve means (142 and 144) being subjected to said throttle pressure signal and said governor pressure signal which establish opposed forces thereon ; a shift modulator valve means (214) between siad throttle valve means (106) and said shift valve means (144) for establishing a downshifting force on the latter which effects a desired upshift point upon increases in said speed signal ; and a downshift control valve means (280) communicating with said clutch means (C1 2 ) and said shift modulator valve means (214) for developing a modulated pressure signal that affects the modulating action of the shift modulator valve means (214) to effect a desired downshift point that is independent of the speed at which an upshift occurs for any given throttle pressure.
Claim 3
Dependent Claim
101 words
The combination as set forth in Claim 1 characterized in that, said shift modulator valve means (214) comprises a modulating valve element and a spring (282) acting thereon tending to restrict the degree of communication between said throttle valve means (106) and said shift valve means (144), the modulated torque signal developed by said shift modulator valve means (214) acting on said valve element to assist the force of said spring ; said downshift control valve means (280) and said shift modulator valve means (214) being connected whereby the signal from the former affects the shift point established by the latter.
Claim 4
Dependent Claim
37 words
The combination as set forth in Claim 1 and 2, characterized in that, the signal from said downshift control valve means (280) which acts on said shift modulator valve means (214) opposes the force of said spring.
Claim 5
Dependent Claim
47 words
The combination as set forth in Claim 1 to 3, characterized in that, said downshift control valve means (280) is connected to said manual valve means (80) and subjected to pressure distributed to it from said manual valve means (80) when the latter assumes said second position.
Claim 6
Dependent Claim
312 words
A control system for an automatic transmission according to Claim 1, characterized in that, said transmission assuming a high speed ratio (3 rd ) ) condition when said clutch means (C1 1 ) and said release pressure chamber are pressurized simultaneously and assuming an underdrive condition (2 nd ) when said clutch means (Cl 2 ) and said pressure release chamber are exhausted ; separate exhaust pressure flow paths for said clutch means (Cl 1 ) and said release pressure chamber including a common flow path portion (220), said shift valve means (204) being disposed in and forming a part of said common flow path protion (220) ; a downshift kick-down timing valve means (302) and a downshift torque demand timing valve means (322) in the exhaust flow path (202) for said pressure release chamber, each timing valve means being responsive to said speed pressure signal ; the exhaust flow path (202) extending from said release pressure having parallel branches, said downshift kick-down timing valve means (302) being on the exhaust flow upstream side of said downshift torque demand timing valve means (322) ; a plurality of orifices in said exhaust flow paths (202, 220), a first of said orifices (236) being in the exhaust flow path for both the said clutch means (Cl 1 ) and said release pressure chamber and a second of said orifices (320) being in the flow path (202) for said pressure release chamber only ; said timing valve means (302 and 322) each responding to said speed pressure signal to provide a flow path through a first set of said orifices (312, 314, 316) at speeds of said driven member less than a predetermined value (2, 03 kp/cm 2 ) and through a second set (324, 334) of said orifices at speeds of said driven member greater than said predetermined value (3,08 kp/ cm 2 ).
Claim 7
Dependent Claim
112 words
The combination as set forth in Claim 5, characterized in that said timing valve means (302 and 322) each responds to said speed pressure signal to provide a flow path through first ones of said orifices (312, 314, 316) at speeds of said driven member less than a first predetermined value (2, 03 Kp/cm ) and through second ones of said orificies (324, 334) at speeds of said driven member between said first predetermined value (2,03 kp/cm ) and a second predetermined value (3,08 km/cm ) and through third ones of said orificies (324, 236) at speeds of said driven member greater than said second predetermined value (3, 08 kp/cm 2 ).
Claim 8
Dependent Claim
77 words
The combination as set forth in Claim 5, chracterized in that said first orifice (334) is located in one of said parallel branches and in the exhaust flow path (202) for said clutch means and the second orifice (324) is located in the other of said parallel branches, said timing valve means (302 and 322) responding to changes in said speed signal to distribute selectively fluid from said pressure release chamber to each of said parallel branches.
Claim 9
Dependent Claim
25 words
The combination as set forth in Claim 5 to 7, characterized in that said common flow path portion includes additional calibrated flow control orificies (236).
Claim 10
Dependent Claim
45 words
' The combination as set forth in Claim 7, characterized in that said first orifice (320) is located in said one of said parallel branches in series relationship with said downshift kick-down timing valve means (302) and said downshift torque demand timing valve means (322).
Claim 11
Dependent Claim
148 words
The combination as set forth in Claim 1 to 5, characterized in that, a manual downshift modulating valve means (228) in said conduit structure between said shift valve means (204) and said clutch means (Cl 1 ) whereby the pressure flow path between said pressure source (70) and said clutch means (Cl 1 ) includes a first pressure,line (96) extending from said source (70) and a second pressure line extending from said shift valve means (144), said manual downshift modulating valve means (228) responding to pressure distributed to it through said second pressure line following a downshift of said shift valve means (144) to effect controlled communication between said clutch means (Cl 1 ) and said first pressure line, said manual downshift modulating valve means (228) modulating the pressure delivered to it through said first pressure line in response to a pressure buildup in said seconds pressure line.
References Cited (Backward Citations)
No citation records indexed.
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