US3791239A — Vehicle transmission control system for vehicles

Claim 1

Independent Claim 279 words

In combination with an engine and a transmission driven by the engine at a plurality of different drive ratios, a pair of speed sensing devices respectively driven by the engine and the transmission for generating fluid signal pressures, means for modulating the signal pressure produced by the engine driven speed sensing device as a function of the drive ratio of the transmission, and drive control means responsive to the modulated signal pressure and the signal pressure produced by the transmission driven speed sensing device for changing the drive ratio of the transmission, the modulating means including a first piston device having a signal pressure chamber to which the engine driven speed sensing device is connected, a pressure face responsive to signal pressure applied from the engine driven speed sensing device and control chamber means for opposing displacement of the signal pressure face a second piston device having opposed pressure chambers and pressure faces therein, first throttling valve means connected to the signal pressure chamber of the first piston device for supplying a reduced signal pressure fluid to one of the opposed pressure chambers of the second piston device, second throttling valve means connected to the first throttling valve means for further reducing the signal pressure to produce said modulated signal pressure applied to the drive control means, and selectively controlled valve means actuated by the drive control means including a shifting member for controlling the application of reduced signal pressure to the control chambers means of said first piston device and the other of the opposed pressure chambers of said second piston device respectively, to vary the reductions in signal pressure by the first and second throttling valve means.

Claim 2

Dependent Claim 279 words

In combination with an engine and a transmission driven by the engine at a plurality of different drive ratios, a pair of speed sensing devices respectively driven by the engine and the transmission for generating fluid signal pressures, means for modulating the signal pressure produced by the engine driven speed sensing device as a function of the drive ratio of the transmission, and drive control means responsive to the modulated signal pressure and the signal pressure produced by the transmission driven speed sensing device for changing the drive ratio of the transmission, the modulating means including a first piston device having a signal pressure chamber to which the engine driven speed sensing device is connected, a pressure face responsive to signal pressure applied from the engine driven speed sensing device and control chamber means for opposing displacement of the signal pressure face a second piston device having opposed pressure chambers and pressure faces therein, first throttling valve means connected to the signal pressure chamber of the first piston device for supplying a reduced signal pressure fluid to one of the opposed pressure chambers of the second piston device, second throttling valve means connected to the first throttling valve means for further reducing the signal pressure to produce said modulated signal pressure applied to the drive control means, and selectively controlled valve means actuated by the drive control means including a shifting member for controlling the application of reduced signal pressure to the control chambers means of said first piston device and the other of the opposed pressure chambers of said second piston device respectively, to vary the reductions in signal pressure by the first and second throttling valve means.

Claim 3

Dependent Claim 118 words

The combination of claim 1 wherein the first piston device further includes a plurality of control pressure faces within the control chamber means having pressure exposed areas progressively larger than the area of the signal pressure responsive face, the pressurE face in said other of the opposed pressure chambers of the second piston device having a larger area than that of the pressure face in said one of the opposed chambers, the ratio of pressure face areas in the second piston device being a predetermined progression factor and the face area ratios of the control pressure faces to the signal pressure responsive face of the first piston device being greater than said progression factor by increasing powers thereof.

Claim 4

Dependent Claim 64 words

The combination of claim 2 wherein the first piston device further includes a reciprocable element having said signal pressure face at one axial end and a flange axially spaced therefrom, and a plurality of sleeves telescopingly mounted on the element in abutment with the flange, the control pressure faces in the control chamber means being formed on the sleeves at ends remote from flange.

Claim 5

Dependent Claim 92 words

The combination of claim 3 including a transmission having a drive ratios, wherein the drive control means includes a shifting member engageable with said selectively controlled valve means, while the area ratio of the opposed pressure faces effective when shifting into a determined drive ratio to the signal pressure responsive face is ( phi a n), where n represents the drive gear condition number and ( phi ) the progression factor of the drive ratios which is equal to the area ratio of the opposed pressure faces in the second piston device.

Claim 6

Dependent Claim 92 words

The combination of claim 2 including a transmission having a drive ratios wherein the drive control means includes a shifting member engageable with said selectively controlled valve means, while the area ratio of the opposed pressure faces effective when shifting into a determined drive ratio to the signal pressure responsive face is ( phi a n), where n represents the drive gear condition number and ( phi ) the progression factor of the drive ratios which is equal to the area ratio of the opposed pressure faces in the second piston device.

Claim 7

Dependent Claim 131 words

The combination of claim 2, wherein the drive control means includes a shifting member engageable with one of the control valve means associated either with said first piston device (A, B, C) or with said second piston device (D) and with two of said valve means combined (A + D; B + D . . . ) to attain area ratios of the control pressure faces to the signal pressure responsive face of the first piston device, which ratios being powers of the progression factor ( phi ) the exponents of said powers ( phi 1, phi 3, phi 5 . . . ; phi 2, phi 4, phi 6 . . . ) forming a series of whole numbers each two consecutive members of which differ by the number two.

Claim 8

Dependent Claim 30 words

The combination of claim 1, including engine control means operatively connected to the drive control means for effecting synchronism between the engine and the transmission in response to pressure signals.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1977-02-11	1977-08-13	1978-02-12	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1981-02-11	1981-08-13	1982-02-12	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1985-02-11	1985-08-13	1986-02-12	$7700.00	Window Closed / Lapsed

Vehicle transmission control system for vehicles

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