A brake system for controlling a brake of a unit hauled by a vehicle, the brake system including a first pedal for braking a right rear wheel of the vehicle through a first braking circuit, a second pedal for braking a left rear wheel of the vehicle through a second braking circuit, an input line arrangement including a first input line for receiving a fluid from the first braking circuit and a second input line for receiving a fluid from the second braking circuit, at least one output line for sending a fluid to the brake of the hauled unit, and a selective connector for selectively connecting the input line arrangement to the output line by setting a first connection configuration when the vehicle has a speed greater than a threshold value and a second connection configuration when the vehicle has a speed lower than the threshold value, whereby in the first connection configuration pushing any of the pedals activates the brake of the hauled unit, and in the second connection configuration pushing only one of the pedals leaves the brake of the hauled unit inactive, so that the vehicle can be steered by braking.

A steer/brake system for a vehicle (with wheels and/or tracks) is disclosed. The system may comprise a steering system with an operator control and braking system for each side of the vehicle with a master cylinder for the brake mechanism and an interface between the braking system and the operator control. Operation may provide a phase where the interface is at least partially engaged and force may be applied through the interface to the master cylinder to engage the brake mechanism to provide modulation for the operator control. A steering emulation system may comprise the interface and a compliant element configured to provide modulation for the operator control. The system may comprise a shared hydraulic system; the brake mechanism may comprise the steering brake mechanism and the service brake mechanism.

A hydraulic brake assembly (12) includes a housing (24) having first and second side-by-side bores (30), each defining a respective master cylinder assembly. Each master cylinder assembly includes a master cylinder piston (32) slidably movable by actuation of a respective brake pedal (18a, 18b) to and between an active position and an inactive position. A spool (74) slidably disposed within a piston bore (70) of the master cylinder piston (32) is operable in a first mode to direct hydraulic fluid from a quick-fill chamber (62) to a master cylinder chamber (50) at a first pressure upon initial movement of the master cylinder piston (32) from the inactive position toward the active position. The spool (74) is operable in a second mode to direct hydraulic fluid from the quick-fill chamber (62) to a tank (20) when pressure in the master cylinder chamber (50) reaches a predefined threshold.

A hydraulic brake assembly (12) includes a housing (24) having first and second side-by-side bores (30), each defining a respective master cylinder assembly. Each master cylinder assembly includes a master cylinder piston (32) slidably movable by actuation of a respective brake pedal (18a, 18b) to and between an active position and an inactive position. A spool (74) slidably disposed within a piston bore (70) of the master cylinder piston (32) is operable in a first mode to direct hydraulic fluid from a quick-fill chamber (62) to a master cylinder chamber (50) at a first pressure upon initial movement of the master cylinder piston (32) from the inactive position toward the active position. The spool (74) is operable in a second mode to direct hydraulic fluid from the quick-fill chamber (62) to a tank (20) when pressure in the master cylinder chamber (50) reaches a predefined threshold.

A method of brake steering in a four-wheel drive utility vehicle having a driven front axle carrying at least two front wheels, a driven rear axle carrying at least two rear wheels, a powertrain delivering torque to the front and rear axles via a connecting shaft, a controlled clutch arrangement in the connecting shaft operable to vary the distribution of delivered torque between the front and rear axles, and independently operable service brakes on each of the front and rear wheels. The method comprises, on the vehicle entering a turn, applying the service brakes of the front and rear wheels on the inside of the turn and adjusting the clutch arrangement to adapt the share of the available torque between the front and rear axles. Additional braking force may be applied from independently operable park brakes on the rear wheels in inverse relationship to the level of service brake force applied.

A method of brake steering in a four-wheel drive utility vehicle having a driven front axle carrying at least two front wheels, a driven rear axle carrying at least two rear wheels, a powertrain delivering torque to the front and rear axles via a connecting shaft, a controlled clutch arrangement in the connecting shaft operable to vary the distribution of delivered torque between the front and rear axles, and independently operable service brakes on each of the front and rear wheels. The method comprises, on the vehicle entering a turn, applying the service brakes of the front and rear wheels on the inside of the turn and adjusting the clutch arrangement to adapt the share of the available torque between the front and rear axles. Additional braking force may be applied from independently operable park brakes on the rear wheels in inverse relationship to the level of service brake force applied.

When left and right steering levers are both operated and the operation amount of the left lever is larger than that of the right lever, a controller calculates a correction left operation amount of the left lever according to the operation amount of the right lever, and controls a left steering clutch so as to cause a vehicle body to turn toward the left in accordance with the correction left operation amount. When left and right steering levers are both operated and the operation amount of the right lever is larger than that of the left lever, the controller calculates a correction right operation amount of the right lever according to the operation amount of the left lever, and controls a right steering clutch so as to cause the vehicle body to turn toward the right in accordance with the correction right operation amount.

When left and right steering levers are both operated and the operation amount of the left lever is larger than that of the right lever, a controller calculates a correction left operation amount of the left lever according to the operation amount of the right lever, and controls a left steering clutch so as to cause a vehicle body to turn toward the left in accordance with the correction left operation amount. When left and right steering levers are both operated and the operation amount of the right lever is larger than that of the left lever, the controller calculates a correction right operation amount of the right lever according to the operation amount of the left lever, and controls a right steering clutch so as to cause the vehicle body to turn toward the right in accordance with the correction right operation amount.

A riding lawn care vehicle (10) may include a frame (60), a steering assembly (30), a brake assembly (110), and a mechanical brake linkage assembly (120). At least a first drive wheel (32) and a second drive wheel (32) of the riding lawn care vehicle (10) may be attachable to the frame (60). The steering assembly (30) may include a first steering lever (34) and a second steering lever (34), where the first and second steering levers (34) are operably coupled to the first and second drive wheels (32) respectively to facilitate turning of the riding lawn care vehicle (10) based on drive speed control of the first and second drive wheels (32) responsive to positioning of the first and second steering levers (34) along a first direction when the first and second steering levers are in an operating position. The brake assembly may be operably coupled to the first and second drive wheels (32) to enable brakes to be selectively applied to the first and second drive wheels (32). The mechanical brake linkage assembly (120) may be configured to activate the brake assembly (110) relative to the first and second drive wheels (32) in response to movement of the first and second steering levers (34) in a direction parallel to the first direction after the first and second steering levers (34) have been moved from the operating position to a non-operating position.

A steer/brake system for a vehicle (with wheels and/or tracks) is disclosed. The system may comprise a steering system with an operator control and braking system for each side of the vehicle with a master cylinder for the brake mechanism and an interface between the braking system and the operator control. Operation may provide a phase where the interface is at least partially engaged and force may be applied through the interface to the master cylinder to engage the brake mechanism to provide modulation for the operator control. A steering emulation system may comprise the interface and a compliant element configured to provide modulation for the operator control. The system may comprise a shared hydraulic system; the brake mechanism may comprise the steering brake mechanism and the service brake mechanism.