Qinetiq Limited

Renk America LLC

Other

Robert William Thompson

Robert John Bonner Flaxman

A drive unit for a skid steered vehicle includes a controlled differential positioned between two shafts. The end of each shaft forms an output of the drive unit connected directly to the differential outputs via the shafts. A steer motor is in driveable communication with the differential, and an electric propulsion motor is in driveable communication with the shaft outputs. A gear reduction unit, and optional gear change unit, is positioned between the differential and the electric propulsion motor. The electric propulsion motor, the gear reduction unit and optional gear change unit are connected in a parallel connection with an output of the differential to the shaft outputs. The optional gear change unit includes an epicyclic gear reduction unit having an input and an output which provides drive input from the gear change unit to the shaft. A gear change set has a master gear that receives drive output from the electric propulsion motor, and slave gears which are driven by the master gear via one or more gear chains. A dog clutch slideably engages the input of the gear reduction unit and selectively engages with the master gear or slave gears so that the selected position of the dog clutch determines which gear is engaged.

Drive system for a skid steered vehicle

Gearboxes for a skid steered vehicle including layouts in which all electric propulsion drive motors and electric steering motors are located on one side of the gearbox, and layouts in which the drive inputs of the electric propulsion drive motors are located face to face. Gear change units and gear packaging configurations suitable for such gearboxes.

Some embodiments are directed toward a transmission having a torque input and output, drive members selectively engageable for sequentially changing gear ratio between the torque input and output, the transmission also having a shaft with a shifting feature. The transmission includes a drum having a track around its outer perimeter and arranged such that torque can be transferred by rotating the shaft, the drum capable of being moved along the length of the shaft, a biasing mechanism for urging the drum towards a rest position along the length of the shaft, and a drive member selector member provided in operative relation to the track, wherein by rotating the shaft the drive member selector member can be selectively urged into contact with a first drive member for drivingly engaging therewith in a first torque connection or into contact with a second drive member for drivingly engaging in a second torque connection.

Transmission for blocking upshifts and downshifts under certain torque conditions

Some embodiments are directed to a gearing assembly including a rotary input member, a rotary output member and a gearing arrangement between the input member and the output member selectively engageable to effect a driving engagement between the input member and the output member through at least a first torque connection having a first gear ratio and a second torque connection having a second gear ratio. One of the rotary input member and the rotary output member includes a first shaft and the first torque connection includes a first dog clutch including a dog hub having a hub set of teeth and a surrounding dog ring including a ring set of teeth. The hub and ring sets of teeth are radially projecting and mutually engageable. The dog hub is mounted on the first shaft so as to allow axial movement of the dog hub relative to the shaft.

Gearing assemblies and apparatus

Some embodiments are directed to a transmission including a plurality of shafts, each carrying a plurality of drive members, the drive members on each shaft arranged to operatively cooperate with those carried by at least one other shaft for transferring load between a torque input and a torque output of the transmission in use, the transmission being configured such that respective resultant gear ratios between the torque input and the torque output can be selected in use from each of a plurality of groups thereof by changing a load path between the torque input and the torque output, wherein each group of selectable resultant gear ratios has a load path feature for transferring load between a pair of the shafts which is common to the selectable resultant gear ratios within that group.

Multiple gear range transmission

Some embodiments are directed to a gearbox including first and second rotational members, the first rotational member having a shaft portion extending away from the gearbox, the first rotational member carrying one or more projections, the second rotational member carrying one or more complementary projections, the projections carried by the first rotational member being configured to be drivingly engaged with the complementary projections carried by the second rotational member to transmit torque in a first torque connection but not in a torque connection that is opposed to the first torque connection. The gearbox further includes a one way clutch adapted such that the first and second rotational members can be drivingly engaged to transmit torque in a second torque connection, wherein the second torque connection is opposed to the first torque connection.

Gearbox improvements

A gearing assembly includes a rotary input member, a rotary output member, and a gearing arrangement between the input member and the output member selectively able to effect a driving engagement between the input member and the output member through at least a first torque connection having a first gear ratio. A second torque connection has a second gear ratio and a third torque connection having a third gear ratio. The gearing arrangement includes a first engagement member operable selectively to effect the first torque connection in a 1:1 ratio, a first planetary gear stage, and a second planetary gear stage. A second engagement member is operable selectively to effect the second torque connection, and a third engagement member operable selectively to effect the third torque connection, respectively, through one or more of the planetary gear stages.

Gearing assembly, vehicle drivetrain and electric wheel hub therewith

A drive member selection mechanism is described, including at least one drive member and at least two selector members, wherein the drive member includes a first and second face, and further includes, on each face, at least one projection, and the selector members include, on at least one face thereof, at least one complementary projection arranged to selectively engage with a projection of a drive member, the arrangement being such that the projection(s) of a selector member and the projection(s) of the first face of a drive member may be drivingly engaged in a first torque connection and the projection(s) of a selector member and the projection(s) of the second face of a drive member may be drivingly engaged in a second torque connection, wherein the second torque connection is opposed to the first torque connection.

Drive member selection

A shifting apparatus including a shaft extending along an axis, and at least one shifting feature, each of the at least one shifting feature including: a multi-part pin having first and second parts arranged to rotate relative to each other that extend through respective slots extending along the shaft; a drum arranged around the shaft and having channels extending along the length thereof wherein the first and second parts of the multi-part pin are respectively received for enabling torque transfer to the drum when the shaft is rotated, the drum also defining a track at least partially around its outer surface; a biasing mechanism for urging the drum towards a rest position along the length of the shaft; and a drive member selector member provided in operative relation to the track. The drive member selector member can be controlled to selectively engage a drive member.

Shifting apparatus

A chainless drive mechanism for a bicycle using pedal arms, one on each side of the bicycle, each pedal arm carrying a pedal engageable with a rider's foot. Each pedal arm is mounted to a crank by a rotating joint and connected to the frame of the bicycle by a link, each link having rotating joints at each end. The cranks are connected by a shaft passing through the hub of to the driven wheel of the bicycle. The cranks may be connected to the driven wheel by a multi ratio free wheeling gear mechanism.

Bicycle transmission

A drive configuration for a skid steered vehicle comprises a pair of electric motors for propulsion of the vehicle, one each coupled to drive a respective track on a respective side of the vehicle, and one or more electric steer motors coupled through a differential gear mechanism to impose a speed difference between the tracks. An associated control system controls the current to each motor so that substantial contributions to the differential torque to turn the vehicle are made both by the steer motors and by the propulsion motors, in variable proportions preferably as a function of the vehicle speed.

Drive configuration for skid steered vehicles

A controlled differential, particularly for exercising steering control of skid steered vehicles, having a compound planetary gear set coupling two shafts. Respective ring gears turn with the shafts and mesh with a compound planet gear in a planet carrier, the ratios of the number of gear teeth between each ring gear and the respective gear of the compound planet being unequal so that when the planet carrier is stationary the two shafts are coupled through the differential to turn together in the same sense but with a speed difference, and controlled rotation of the planet carrier varies the speed difference between the shafts in accordance with the sense and speed of rotation of the planet carrier.

Controlled differential

A drive configuration for a skid steered vehicle incorporates a controlled differential for use in exercising steering control of the vehicle, comprising a compound planetary gear set () coupling two shafts (). Respective sun gears () and () turn with the shafts and mesh with compound planet gears () in a common planet carrier (), the ratios of the number of gear teeth between each sun gear and the respective gears () or () of the compound planets being unequal so that when the planet carrier is stationary the two shafts are coupled through the differential to turn together in the same sense but with a speed difference, and controlled rotation of the planet carrier varies the speed difference between the shafts in accordance with the sense and speed of rotation of the planet carrier.

Compound planet steer differential

An electric drive transmission for a skid steered vehicle has a central casing housing a pair of propulsion motors comprising respective stators and rotors, each rotor being coupled to drive a respective through shaft via a respective epicyclic gear change mechanism. The through shafts are coupled at their inboard ends to a controlled differential with an input from a steer motor, and are coupled at their outboard ends to respective epicyclic gear reduction mechanisms. The through shafts are supported in the casing by respective bearings and the propulsion motor rotors are supported on the through shafts by respective bearings. By supporting the rotors on the through shafts rather than in separate bearings to the casing the diameter and speed rating of the requisite rotor bearings can be reduced.

Electric drive transmission

A gear change mechanism coupling a pair of shafts employs a planetary gear set comprising a sun gear fast with a first of the shafts, planet gears in a planet carrier, and an annulus or ring gear, the latter being fixed. A selector hub slidable on the other of the shafts has sets of radially spaced dogs to engage with corresponding dogs on the planet carrier and sun gear respectively, so as to couple the shafts at two different ratios depending on the axial position of the selector hub. This results in a more axially compact package than conventional dog clutch gear changers. In an alternative embodiment a reversing mechanism is provided by fixing the planet carrier and engaging the selector hub with the sun gear or annulus depending on its axial position.

Growing community of inventors

Camberley, United Kingdom

Robert William Thompson