摘要:
The steering system of some lightweight vehicles are electronically controlled and have a manually operated mechanical control as a backup. Such manual backup control would not be adequate for large earthmoving, construction and industrial type vehicles. The subject steering system includes an electrically controlled circuit actuated by rotation of a steering wheel for controlling a main pilot operated steering valve as the primary steering control. A hydraulic control circuit is also actuated by rotation of the steering wheel for controlling the same steering valve as a backup control when the electrically controlled circuit is not active. The hydraulic steering circuit is disabled when the electrically controlled circuit is activated. By using the same steering valve as an integral part of both circuits, the complexity and cost of the overall steering control system is reduced.
摘要:
The present invention provides a sensing system and method for providing information relating to a drivetrain during shifting operations. The drivetrain includes an engine, a torque converter and a transmission. The system includes sensors for detecting the output speed of the engine, the output speed of the torque converter, and the output speed of the transmission. The system detects the starting condition of a shifting operation, responsively determines a set of performance parameters, and produces a set of performance parameter signals.
摘要:
A vehicle such as an earthmoving wheel loader has an engine, a torque converter having an impeller element, a reactor element and a turbine element, and an input clutch connected between the engine and the impeller element. An electrohydraulic control device is provided to controllably engage the input clutch and that includes a microprocessor-based electronic control module, an actuator mechanism having a control member that is progressively movable between first, second and third positions to deliver a first electrical signal to the electronic control module, and a valve for directing fluid to the input clutch at a decreasing pressure level when the control member is moved from the first to the second positions in response to another signal from the electronic control module. The electronic control module is programmed to maintain at least a minimal pressure level to the actuating piston of the input clutch when the control member is between the second and third positions. Moreover, a service brake is increasingly engaged by a service brake mechanism in response to the control member moving between the second and third positions. Other logic functions are included to control the input clutch and a lockup clutch connected between the engine and the turbine element.
摘要:
Vehicles having front and rear pairs of steerable wheels are sometimes provided with large springs for moving one pair of the wheels to a straight-ahead position during emergency steering. Large amounts of hydraulic energy are expended solely for the compression of such springs every time the pair of wheels are steered. A back-up steering control system (19) of the present steering control arrangement (10) has a servo valve (76) operative to control the flow of pressurized fluid from a back-up pump (60) to a steering control valve (21) which in turn controls the flow of pressurized fluid from the back-up pump to a hydraulic actuator (13) to hydraulically move a first pair of steerable wheels (11) to a straight-ahead position during emergency steering conditions. A manual control valve (68) is operative to control the flow of pressurized fluid from the back-up pump (60) to another steering control valve (22) which in turn controls the flow of pressurized fluid to a hydraulic actuator (16) for effecting steering of a second pair of steerable wheels (12) during the emergency steering condition.
摘要:
In one aspect of the present invention, a sensor detects particles within a fluid. The sensor includes a housing that defines a cavity. A magnet is disposed adjacent the cavity bottom to attract particles into the cavity. A first coil is wound about the outer surface of the cavity. The induction of the first coil is responsive to the particle accumulation within the cavity. A second coil is wound about the magnet. The induction of the second coil is responsive to the temperature of the fluid and independent to the particle accumulation within the cavity.
摘要:
Vehicles (12) having implements (14) are typically used to perform repetitive functions in work cycles. Advantageously, such vehicles (12) include control systems (10) for maintaining a control lever (26) in a predetermined position until an associated work cycle function is completed. The subject control (10) includes a rocker bar (46) connected to the control lever (26) and a solenoid (50) having an actuator rod (52) disposed adjacent the rocker bar (46). The control (10) energizes the solenoid (50) to hold the control lever (26) in the predetermined position in response to a position of the implement (14), a position of the control lever (26), and a desired kickout position.
摘要:
An electrohydraulic control device for a drive train of a machine is disclosed. The drive train includes an engine, a transmission, and a torque converter having a rotating housing. The torque converter is drivingly connected between the engine and the transmission. The torque converter also includes an impeller element. An impeller clutch connects the impeller element to the rotating housing. An impeller clutch electrohydraulic valve produces fluid flow to the impeller clutch to controllably engage and disengage the impeller clutch. A torque converter speed sensor senses the output speed of the torque converter and responsively produces a torque converter speed signal. A electronic device receives the measured torque converter speed signal, determines a desired torque convertor speed signal, produces an error speed signal in response to a difference between the measured and desired torque converter speed signals, and controllably actuates the electrohydraulic valve to cause the speed error signal to approach zero.
摘要:
An overshot loader including a set of ground engaging members, a frame attached to the set of ground engaging members, and a linkage assembly movably connected to the frame and located within a longitudinal center portion of the frame.
摘要:
An anti-spin apparatus for a machine is disclosed. The machine is articulated and has at least one axle set with at least two driven wheels. The anti-spin apparatus includes braking mechanisms which controllably apply braking forces to each of the driven wheels. A controller produces a slip signal having a value responsive to the difference in rotational velocity between the wheels of the axle set. A transducer produces an articulation signal having a value responsive to the angle of articulation of the machine. Further, a microprocessor receives the slip signal and the articulation signal, and produces a braking control signal. One of the braking mechanisms receives the braking control signal and responsively applies the braking forces to the faster rotating wheel.