POWER STEERING SYSTEM FOR A VEHICLE
First Claim
1. A power steering system for a vehicle, the vehicle comprising a traction engine designed to drive wheels through a driveline comprising an upstream portion which is connected to the engine and a downstream portion which is permanently connected to the drive wheels, the power steering system comprisinga hydraulic circuit including a fluid tank and a steering actuator,a first pump which is driven by mechanical power from the downstream portion of the driveline;
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wherein the first and second pumps are arranged in parallel between the fluid tank and the steering actuator and are capable of supplying fluid from the fluid tank to the steering actuator at the same time.
3 Assignments
0 Petitions
Accused Products
Abstract
In a vehicle including a traction engine designed to drive wheels through a driveline that includes an upstream portion which is connected to the engine and a downstream portion which is permanently connected to the drive wheels, the power steering system includes a hydraulic circuit including a fluid tank and a steering actuator. The power steering system further includes a first pump which is driven by mechanical power from the downstream portion of the driveline, and a second pump which is driven by an electric motor. The first and second pumps are arranged in parallel between the fluid tank and the steering actuator and are capable of supplying fluid from the fluid tank to the steering actuator at the same time.
14 Citations
14 Claims
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1. A power steering system for a vehicle, the vehicle comprising a traction engine designed to drive wheels through a driveline comprising an upstream portion which is connected to the engine and a downstream portion which is permanently connected to the drive wheels, the power steering system comprising
a hydraulic circuit including a fluid tank and a steering actuator, a first pump which is driven by mechanical power from the downstream portion of the driveline; - and
a second pump which is driven by an electric motor; wherein the first and second pumps are arranged in parallel between the fluid tank and the steering actuator and are capable of supplying fluid from the fluid tank to the steering actuator at the same time. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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10. A vehicle comprising
a traction engine designed to drive wheels through a driveline comprising an upstream portion which is connected to the engine and a downstream portion which is permanently connected to the drive wheels, and a power steering system for a vehicle, the vehicle comprising a traction engine designed to drive wheels through a driveline comprising an upstream portion which is connected to the engine and a downstream portion which is permanently connected to the drive wheels, the power steering system comprising a hydraulic circuit including a fluid tank and a steering actuator, a first pump which is driven by mechanical power from the downstream portion of the driveline; - and
a second pump which is driven by an electric motor; wherein the first and second pumps are arranged in parallel between the fluid tank and the steering actuator and are capable of supplying fluid from the fluid tank to the steering actuator at the same time. - View Dependent Claims (11)
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12. A method for controlling a power steering system for a vehicle, the vehicle comprising a traction engine designed to drive wheels through a driveline comprising an upstream portion which is connected to the engine and a downstream portion which is permanently connected to the drive wheels, the power steering system comprising
a hydraulic circuit including a fluid tank and a steering actuator, a first pump which is driven by mechanical power from the downstream portion of the driveline; - and
a second pump which is driven by an electric motor; wherein the first and second pumps are arranged in parallel between the fluid tank and the steering actuator and are capable of supplying fluid from the fluid tank to the steering actuator at the same time, the method comprising controlling operation of the first pump and/or the second pump so that, at low vehicle speed, the second pump delivers a fluid flow high enough to compensate for the low fluid flow delivered by the first pump, in order to ensure a sufficient fluid supply to the steering actuator. - View Dependent Claims (13, 14)
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Specification