Abstract: A drivetrain for an agricultural vehicle and method for controlling the same. The drivetrain includes first and second driven axles with a variable pivot angle hydraulic motor connectable to drive the first axle through engagement of a first clutch mechanism. A further motor is connected to drive the second axle. In operation, the pivot angle of the variable pivot angle hydraulic motor is reduced with variation in a vehicle parameter value, such as transmission ratio or ground speed, to a point at which the pivot angle reaches zero at a first parameter value. With the pivot angle at zero and parameter value continuing to vary due to the drive of the further motor, the first clutch mechanism is disengaged at a second parameter value, with the first and second parameter values separated by an interval determined at least partly by an operating characteristic of the first clutch mechanism.

Abstract: A tire pressurization arrangement on a vehicle in which the pressurization of the tire is controlled by a vehicle control unit and the vehicle control unit is notified of a desired tire pressure or desired tire volume. An air flow rate in a supply line to the tire is established so that the time to pressurize the tire to the desired tire pressure/volume is calculable, or the time taken to pressurize the tire to an interval pressure/volume is calculable, said interval pressure/volume being between a current tire pressure/volume and the desired pressure/volume, and if the time to pressurize the tire to the desired pressure is exceeded, the control unit gives a warning signal and/or stops deflation or inflation.

Abstract: An air supply system on a vehicle having a tire. The system includes a compressor having a supply mode for supplying air to a consumer connected to the compressor. The consumer is provided with a reservoir and the compressor switches to an idle mode when the pressure of the reservoir attains a first predetermined reservoir pressure. During a supply period when the consumer is supplied with air from the compressor, the pressure of at least one tire is measured and prior to a subsequent tire pressure measurement, air is discharged from the reservoir so that the compressor remains in the supply mode and the consumer and/or reservoir continues to be supplied with air.

Abstract: A drivetrain for an agricultural vehicle and method for controlling the same. The drivetrain includes first and second driven axles with a variable pivot angle hydraulic motor connectable to drive the first axle through engagement of a first clutch mechanism. A further motor is connected to drive the second axle. In operation, the pivot angle of the variable pivot angle hydraulic motor is reduced with variation in a vehicle parameter value, such as transmission ratio or ground speed, to a point at which the pivot angle reaches zero at a first parameter value. With the pivot angle at zero and parameter value continuing to vary due to the drive of the further motor, the first clutch mechanism is disengaged at a second parameter value, with the first and second parameter values separated by an interval determined at least partly by an operating characteristic of the first clutch mechanism.

Abstract: A method of inflating and deflating a tire on a vehicle, said vehicle having a rotatable air passage connectable to a tire and a non rotatable air passage through which air is conducted from a pressurized air supply. One of the passages has an associated sealing means for co-operating with a contact component associated with the other passage and wherein prior to inflation and deflation of the tire, one of the passages is pressurized to ensure the integrity of the sealing means with the contact component.

Abstract: A tire pressurization arrangement on a vehicle in which the pressurization of the tire is controlled by a vehicle control unit and the vehicle control unit is notified of a desired tire pressure or desired tire volume. An air flow rate in a supply line to the tire is established so that the time to pressurize the tire to the desired tire pressure/volume is calculable, or the time taken to pressurize the tire to an interval pressure/volume is calculable, said interval pressure/volume being between a current tire pressure/volume and the desired pressure/volume, and if the time to pressurize the tire to the desired pressure is exceeded, the control unit gives a warning signal and/or stops deflation or inflation.

Abstract: A tire pressure control arrangement for a vehicle having at least two tires connected to an air supply. Each tire is connected to the air supply via a supply line having a first valve connected to a second valve. The arrangement further includes a pressure sensor between the two valves. The first valve is closed while the supply line is connected to a pressure supply and the pressure in the supply line is monitored for a pre-determined period of time by a control system on the vehicle to detect whether there are any leaks in the arrangement.

Abstract: A tire pressurization arrangement on a vehicle in which the pressurization of the tire is controlled by a vehicle control unit and the vehicle control unit is notified of a desired tire pressure or desired tire volume. An air flow rate in a supply line to the tire is established so that the time to pressurize the tire to the desired tire pressure/volume is calculable, or the time taken to pressurize the tire to an interval pressure/volume is calculable, said interval pressure/volume being between a current tire pressure/volume and the desired pressure/volume.

Abstract: An air supply system on a vehicle having a tire. The system includes a compressor having a supply mode for supplying air to a consumer connected to the compressor. The consumer is provided with a reservoir and the compressor switches to an idle mode when the pressure of the reservoir attains a first predetermined reservoir pressure. During a supply period when the consumer is supplied with air from the compressor, the pressure of at least one tire is measured and prior to a subsequent tire pressure measurement, air is discharged from the reservoir so that the compressor remains in the supply mode and the consumer and/or reservoir continues to be supplied with air.

Abstract: A pilot controlled valve including an air inlet passage, an air outlet passage and a slider. The slider is moveable within a bore between a closed position and an open position in which the connection between the passages is closed and opened respectively. The slider is provided with a resilient member to bias the slider into the closed position. A part of the slider registers with the bore to define a chamber within the bore, and the slider is provided with a discharge passage that connects the chamber to the inlet passage so that an increase in pressure in the chamber resulting from a leak can be released.

Abstract: A tyre pressurisation arrangement on a vehicle in which the pressurisation of the tyre is controlled by a vehicle control unit and the vehicle control unit is notified of a desired tyre pressure or desired tyre volume. An air flow rate in a supply line to the tyre is established so that the time to pressurise the tyre to the desired tyre pressure/volume is calculable, or the time taken to pressurise the tyre to an interval pressure/volume is calculable, said interval pressure/volume being between a current tyre pressure/volume and the desired pressure/volume.

Abstract: A method of inflating and deflating a tyre on a vehicle, said vehicle having a rotatable air passage connectable to a tyre and a non rotatable air passage through which air is conducted from a pressurised air supply. One of the passages has an associated sealing means for co-operating with a contact component associated with the other passage and wherein prior to inflation and deflation of the tyre, one of the passages is pressurised to ensure the integrity of the sealing means with the contact component.

Abstract: A tire inflation arrangement on a vehicle, said arrangement comprising a rotatable part with a rotatable air passage connected to an air supply and a tire. The arrangement comprises a non-rotatable part on, or through which air from the air supply is conducted. One of said parts is provided with a sealing means for co-operating with a contact surface of the other part. A first valve means (222) and a second valve means (223) are positioned in series along a supply line which extends between the tire and the air supply and each of said valve means (222, 223) is moveable between an open and a closed position in which the flow of air along the supply line is permitted and blocked respectively.

Abstract: A tire pressure control arrangement for a vehicle having at least two tires connected to an air supply. Each tire is connected to an air supply via a respective supply line having a respective valve means (223) and the respective valve means is connected to a second valve means (222). The arrangement further comprises a pressures sensor (38) between the respective valve means (223) and the second valve means (222). The respective valve means (223) is closed while the supply line is connected to a reference pressure supply and the reference pressure in the supply line is monitored for a pre-determined period of time by a control system on the vehicle to detect whether there are any leaks in the arrangement.