Massey-ferguson Services N.v.

Massey Ferguson, S.a.

Massey-ferguson Inc.

Jean J Lasoen

Paul R Chervenak

Transmissions

A system for controlling the selection of the operative ratio of a vehicle powershift transmission driven from an engine via a main clutch. The system includes a clutch status sensor for sensing engaged and disengaged conditions of the main clutch. A selector is provided for selecting the operative ratio of the transmission. Also, a control circuit is provided which includes a ratio-change modulating function which, when the main clutch is engaged and a change to a non-adjacent ratio is selected, invokes a serial routine which ensures that each intermediate ratio between the current ratio and the selected ratio is engaged for a moment to ensure a smooth substantially jerk-free progression between the current ratio and the selected ratio. When the main clutch is disengaged and a change to a non-adjacent ratio is selected, the control circuit invokes a direct routine which permits changes from a current ratio to a non-adjacent selected ratio without engagement of any intermediate ratio.

Controlling powershift transmissions

A control system for the control of a fluid pressure-operated clutch (12) is provided. It includes a fluid pressure-operated clutch actuator (14) and a source of pressurized fluid (15). A fluid flow control valve (18) controls the flow of pressurized fluid to and exhaust of fluid from the actuator. A manually operable clutch control member (19) (e.g. a pedal) is connected via a linkage (20) to the valve (18) to enable engagement/disengagement of the clutch by operation of the control member. An electrical actuator (33) is also provided for operation of the valve, and hence clutch, independently of the manually operable clutch control member. The system further includes a sensor (19a) for sensing the position of the clutch control member and an electrical control circuit (21) for independent control of the valve in response to predetermined vehicle operating criteria. The electrical control circuit is capable of commanding complete disengagement of the clutch irrespective of the position of the clutch control member but is only capable of commanding a level of clutch engagement up to that set by the clutch control member position.

Control system for fluid pressure operated clutch

A transmission selector mechanism including two selector members (50, 51) connected with two coupling members (6, 7) each coupling member being axially slidable in both directions either side of a neutral position to couple a selected one of a pair of gears (10, 12: 11, 13) to an associated shaft (4, 5). The coupling members are connected with the selector members via an epicyclic gear train (56, 55, 54, 52). A first element (52) of the epicyclic is connected with one selector member (50), a second element (56) of the epicyclic is connected with one coupling member (6), and a third element (55) of the epicyclic is connected with the other selector member (5) and the other coupling member (7). The arrangement is such that by appropriate movement of the two selector members (50, 51) both coupling members (6, 7) can be positioned either on the same or opposite sides of their respective neutral positions. The other selector member (51) may operate in a control gate (51' ) in part of which the other selector member (51) is disconnected from the other coupling member (7) and selects operative ratios of an additional transmission stage or stages.

Transmission ratio selector mechanism

Gearbox selector mechanism

A power take-off drive unit for use at the front of a tractor, in which a housing supports input and output shafts for rotation with the input shaft above the output shaft and a gear train connecting the two shafts. An oil-cooled clutch is provided within the housing which is mounted concentrically with the higher input shaft. Coolant oil is supplied to cool the clutch and a scavenging pump is driven from the input shaft for scavenging coolant oil from within the housing to ensure an oil level within the housing below the clutch to minimize the power losses due to churning of the clutch within the coolant oil while still immersing at least part of the gear train. A bearing support for a pivot of a front axle of the tractor is also carried by the housing.

Power take-off drive unit

Vehicle transmission

Tractor draft sensing apparatus with sensing unit positioned outboard of

A tractor draft sensing apparatus in which an elongated sensing shaft is supported in spaced fulcrum supports and carries a pair of draft links on its end portions located outward of the supports. Draft force signals are provided by an elongate member which is attached at one end to the shaft, extends generally parallel to the shaft, and carries at its other end a follower which engages a cam and pivots the cam to give a signal proportional to shaft bending and hence to the draft forces applied to the shaft. The elongate member also carries a separate follower which engages a guide surface on a guidance member to ensure that the elongate member moves relative to the shaft generally in a horizontal plane only during shaft bending. The shaft may also be shaped so that its neutral axis between the fulcrum supports is displaced transversely of the shaft, generally in the direction of application of the draft force, relative to its neutral axis location within the supports.

Draft sensing apparatus

A brake assembly for engaging the periphery of a rotatable member, the brake assembly being energized by rotation of the rotatable member in either direction. The brake assembly includes a movable brake shoe which may be forced into contact with the periphery of the rotating member. The brake shoe has spaced apart rollers which are held in engagement with converging ramps on a wedge block. The brake shoe is permitted to shift laterally with respect to the ramps, and as the brake shoe engages the rotating member one of the rollers will move downwardly along one of the ramps to affect self-energization of the brake shoe. The wedge block is provided with a downwardly extending projection which is disposed between the converging ramps, the projection being received within a recess formed in the brake shoe, the recess being of greater width than the projection. The recess and projection limits the lateral shifting of the brake shoe which takes place during self-energization and permits disengagement of the brake shoe even when a lateral shifting force is being imparted to the brake shoe by the rotatable member which would normally cause further self-energization.

Growing community of inventors

Villepreux, France

Jean J Lasoen