Plural output path torque transmitting mechanism-hydraulic clutch for four wheel drive vehicles

Claim 2

A multiple path drive system for a vehicle having at least two pairs of traction wheels, a transmission conditionable for either forward or reverse drive and a plurality of drive axle assemblies including a plurality of torque transmitting members, each of said members connected to an axle assembly; a torque transfer mechanism comprising driven means for receiving an input torque from said transmission, a differential gear mechanism connected to said driven means including an input element driven by said driven means and a pair of output elements driven by said input element, said differential gear mechanism allowing relative rotation between said input element and each of said output elements, clutch means associated with at least one of said output elements, said clutch means including a driving member connected to said one of said output elements, a driven member connected to one of said torque transmitting members, and a pressure applying means actuable to urge said clutch means into an engaged condition; a source of fluid pressure associated with said transmission; means for receiving fluid pressure from said pressure source; valve means associated with said transmission operative when said transmission is conditioned for forward drive to direct fluid from said pressure source to fluid pressure receiving means and means connected between said fluid pressure receiving means and said pressure applying means such that fluid pressure is communicated to said pressure applying means to engage said clutch when said transmission is conditioned for forward drive.

Claim 3

A multiple path drive system as in claim 1 including one-way driving means disposed between any two elements of said differential gear mechanism and adapted to allow relative overspeed of one of said eLements with respect to the other in a single direction of rotation.

Claim 4

A multiple path drive system as in claim 1 including one-way driving means disposed between said input element of said differential gear mechanism and said output element associated with said clutch means, said one-way driving means allowing relative overspeed of said output element with respect to said input element in a single direction of rotation.

Claim 5

A multiple path drive system as in claim 1 including a drive chain connecting said driving member to one of said output elements.

Claim 6

A multiple path drive system as in claim 1 in which said differential gear mechanism includes a planetary gear set, said input element comprising a planetary carrier driven by said driven means, and a plurality of planet gears on said planet carrier, said output elements comprising a ring gear and a sun gear meshing with said planet gears and driven by said planet carrier and said planet gears.

Claim 7

A multiple path drive system as in claim 1 in which said clutch means includes at least one friction surface associated with said driving member and at least one friction surface associated with said driven member.

Claim 8

A multiple path drive system as in claim 1 in which said transmission includes a hydraulic pump and a forward clutch wherein said source of fluid pressure is said hydraulic pump and said fluid pressure receiving means is said forward clutch.

Claim 9

A multiple path drive system for a vehicle operable in either forward or reverse directions, said vehicle having at least two pairs of traction wheels and an automatic transmission including a source of hydraulic pressure, said transmission conditionable for either forward or reverse drive, said multiple path drive system including a plurality of drive axle assemblies; a plurality of torque transmitting members, each of said members connected to an axle assembly; a torque transfer mechanism comprising driven means for receiving an input torque from said transmission, a differential gear mechanism connected to said driven means including an input element driven by said driven means; a first output element driven by said input element and connected to one of said torque transmitting members, a second output element driven by said input element and connected to the other of said torque transmitting members, said differential gear mechanism dividing torque between said pairs of traction wheels in a ratio relationship thereby allowing differentiation between said first and second output elements, one-way driving means connected between any two elements of said differential gear mechanism whereby when one of said elements overspeeds the other element, said one-way driving means locks said elements together for rotation permitting no differentiation therebetween but when said other element overspeeds said one element, a ratio relationship exists between said output elements for any speed variations, a rotary drive element connected to said second output element, a driven element driven by said rotary drive element, a driving element connectable to said one of said torque transmitting members, clutch means associated with said driven element and said driving element; means for receiving hydraulic pressure from said hydraulic pressure source; valve means associated with said transmission operative when said transmission is conditioned for forward drive to direct hydraulic fluid from said pressure source to said pressure receiving means and means connected between said pressure receiving means and said clutch means such that hydraulic pressure is communicated to said clutch means to urge said clutch means into a fully engaged condition only when said transmission is conditioned for forward drive.

Claim 10

A multiple path drive system for a vehicle operable in either forward or reverse directions, said vehicle having at least two pairs of traction wheels and an automatic transmission including a source of hydraulic pressure, said transmission conditionable for either forward or reverse drive, said multiple path drive system including a plurality of drive axle assemblies; a plurality of torque transmitting members, each of said members connected to an axle assembly; a torque transfer mechanism comprising driven means for receiving an input torque from said transmission, a differential gear mechanism connected to said driven means including an input element driven by said driven means; a first output element driven by said input element and connected to one of said torque transmitting members, a second output element driven by said input element and connected to the other of said torque transmitting members, said differential gear mechanism dividing torque between said pairs of traction wheels in a ratio relationship thereby allowing differentiation between said first and second output elements, one-way driving means connected between any two elements of said differential gear mechanism whereby when one of said elements overspeeds the other element, said one-way driving means locks said elements together for rotation permitting no differentiation therebetween but when said other element overspeeds said one element, a ratio relationship exists between said output elements for any speed variations, a rotary drive element connected to said second output element, a driven element driven by said rotary drive element, a driving element connectable to said one of said torque transmitting members, clutch means associated with said driven element and said driving element; means for receiving hydraulic pressure from said hydraulic pressure source; valve means associated with said transmission operative when said transmission is conditioned for forward drive to direct hydraulic fluid from said pressure source to said pressure receiving means and means connected between said pressure receiving means and said clutch means such that hydraulic pressure is communicated to said clutch means to urge said clutch means into a fully engaged condition only when said transmission is conditioned for forward drive.

Claim 11

A multiple path drive system as in claim 8 in which the one-way driving means are disposed between said input element of said differential gear mechanism and said output element associated with said clutch means, said one-way driving means allowing relative oVerspeed of said output element with respect to said input element in a single direction of rotation.

Claim 12

A multiple path drive system as in claim 8 including a drive chain connecting said driving member to one of said output elements.

Claim 13

A multiple path drive system as in claim 8 in which said differential gear mechanism includes a planetary gear set, said input element comprising a planetary carrier driven by said driven means and a plurality of planet gears on said planet carrier, said output elements comprising a ring gear and a sun gear meshing with said planet gears and driven by said planet carrier and said planet gears.

Claim 14

A multiple path drive system as in claim 8 in which said clutch means includes at least one friction surface associated with said driving member and at least one friction surface associated with said driven member.

Claim 15

A multiple path drive system as in claim 8 in which said transmission includes a forward clutch wherein said fluid pressure receiving means is said forward clutch.

Claim 16

A multiple path drive system as in claim 1 including first and second fluid circuits connected between said valve means associated with said transmission and said clutch applying means whereby said valve means is operative to direct fluid pressure from said pressure source to said first fluid circuit when said transmission is conditioned for forward drive and to direct fluid pressure from said pressure source to said second fluid circuit when said transmission is conditioned for reverse drive.

Claim 17

A multiple path drive system as in claim 14 in which said second fluid circuit includes second valve means adapted to substantially decrease the pressure transmitted from said pressure source to said clutch applying means.