5 results about "Proportional valve" patented technology

The invention discloses an electro-hydraulic servo steering system and a steering control method of a multi-axle vehicle and the multi-axle vehicle with the steering system. The electro-hydraulic servo steering system comprises a hydraulic steering system and an electric control system, wherein the hydraulic steering system comprises a variable pump, power-assisted steering oil cylinders and a servo proportional valve; the power-assisted steering oil cylinders are at least arranged on various rear steering axles; the servo proportional valve is used for controlling the trend of an oil path and the flow adjustment; the electronic control system comprises a lower controller and an upper controller; the lower controller is in signal connection with the servo proportional valve on each steering axle and forms closed loop control; and the upper controller is used for calculating a target corner of each steering axle according to a first axle corner and a steering mode. According to the invention, the electronic control systems of a two-stage controller is optimized, so that the servo proportional valve and the lower controller form a small closed loop; the lower controller with high frequency response is matched with the servo proportional valve to ensure the precision; and a programmable logic controller is used for main calculation work and transmitting a corner instruction to the each lower controller. The invention has the advantages of simple structural arrangement, safety, reliability and favorable control stability.

The invention provides an electro-hydraulic proportional valve, and belongs to the technical field of hydraulic transmission. The electro-hydraulic proportional valve comprises a valve body, a valve core, a connecting block, a case, a moving ring, a circuit board and a reset mechanism, wherein the valve core is glidingly arranged in the valve body; the connecting block is fixedly arranged at one end of the valve body; an installing space is arranged on the connecting block; the case is fixedly arranged at one end, far away from the valve body, of the connecting block; a magnet is arranged in the case; the moving ring is glidingly arranged in the case and is arranged at the outer side of the magnet in a sleeving way; one end of the moving ring is provided with a fixing end part which extends into the installing space and is fixedly connected with the valve core; a protruding part protruding and extending out of one side of the case is arranged on the circuit board; and the reset mechanism is fixedly arranged at the other end of the valve body, and is elastically connected with the valve core. The electro-hydraulic proportional valve provided by the invention has the advantages thatby starting the reset mechanism, the valve core is regulated to slide in the valve body to a zero position; in addition, the normal movement of the valve core in the valve body cannot be influenced byelastic connection of the reset mechanism and the valve core; errors generated in the manufacturing and assembling processes are eliminated; and the control precision of the electro-hydraulic proportional valve is improved.

The invention discloses a six-mode double-oil-way oil supply system. The system comprises a six-position five-way electro-hydraulic proportional valve, wherein the six-position five-way electro-hydraulic proportional valve is provided with a first oil inlet, a second oil inlet, an oil return port, a first oil outlet and a second oil outlet; the first oil inlet is connected with a first hydraulic pump oil source through a first oil way; the second oil inlet is connected with a second hydraulic pump oil source through a second oil way; the first hydraulic pump oil source and the second hydraulic pump oil source are both connected with an oil tank; the first oil inlet is connected with a pilot overflow valve or a direct-acting overflow valve; and the second oil inlet is connected with a pilot overflow valve or a direct-acting overflow valve. The six-mode double-oil-way oil supply system is reasonable in whole layout, compact in structure, convenient for control, flexible in control, low in power loss, high in system efficiency and high in economic benefit.