Amplitude-changing leveling hydraulic control system for boom type aerial work platform

Abstract

The invention discloses an amplitude-changing leveling hydraulic control system for a boom type aerial work platform. The system comprises an amplitude-changing oil cylinder and a leveling oil cylinder, and further comprises a hydraulic oil tank as well as a load-sensitive pump, an emergency power unit and a rotary table control valve which are connected with the hydraulic oil tank respectively, a gravity descending valve is arranged on the amplitude-changing oil cylinder, a leveling balance valve is arranged on the leveling oil cylinder, and the leveling balance valve is connected with a platform control valve; and the power end of the load-sensitive pump is connected with a power device. The system has the advantages that when an arm support raises in an amplitude-changing mode, the stability and accuracy of amplitude changing and leveling are ensured; when the arm support falls in an amplitude-changing mode, the stability of variable changing and leveling is guaranteed, meanwhile, the problems that shaking is is prone to occur, the stability is poor and the energy consumption is large in an existing scheme are solved; the system is efficient and capable of saving energy in whole, good in amplitude-changing stability, high in leveling precision, particularly simple in emergency falling control and high in reliability; and when an electric control system and a power system of a complete machine fail, safe arm falling can still be realized on the premise of ensuring the leveling performance of the work platform.

Description

technical field [0001] The invention relates to a control system for an aerial work platform, in particular to a boom-type aerial work platform luffing and leveling hydraulic control system. Background technique [0002] Aerial work platforms can replace traditional high-altitude equipment such as scaffolding and hanging baskets, which can increase efficiency by 25-50%, ensure safety, avoid personal accidents, and reduce costs by 30-60%. In recent years, with the rapid development of China's economy and technology and the emphasis on safe operations, aerial work platforms, especially boom-type aerial work platforms, have been widely used in China. For its control system, the current industry is generally in the Double-cylinder hydraulic leveling is usually used on aerial work platforms with a working height of less than 30 meters, and electric proportional leveling is used on aerial work platforms with a working height greater than 30 meters. With the development of hydrauli...

AI Technical Summary

Problems solved by technology

In recent years, with the rapid development of China's economy and technology and the emphasis on safe operations, aerial work platforms, especially boom-type aerial work platforms, have been widely used in China. For its control system, the current industry is generally in the Double-cylinder hydraulic leveling is usually used on aerial work platforms with a working height of less than 30 meters, and electric proportional leveling is used on aerial work platforms with a working height greater than 30 meters. With the development of hydraulic and electronic control technology, electric proportional leveling Because of its advantages of fast response, high leveling accuracy, and no influence from the deflection of the telescopic arm, it is gradually replacing dual-cylinder hydraulic leveling and has become the mainstream leveling solution for boom-type aerial work platforms newly developed by major OEMs. However, Practice has proved that the above-mentioned existing aerial work platform luffing leveling scheme has problems such as energy consumption and poor stability when the boom is luffing and falling, and the oil cylinder is subjected to negative loads, and the balance valve is used to control the luffing oil cylinder. A utility model patent for a gravity lowering control system of an aerial work vehicle is disclosed. It can make the boom lower by its own weight and can achieve a certain energy-saving effect. However, when it works with the electric proportional leveling system, it still needs to be driven by a power source. The energy-saving effect of the leveling cylinder is poor; when the equipment engine, emergency power unit, controller, etc. fail, if the electric proportional leveling scheme is adopted, the existing emergency lowering means cannot keep working during the luffing and lowering process The level of the platform, people and equipment in the working platform will have great potential safety hazards. Chinese patent CN209572272U discloses a utility model patent for an emergency lowering electric control box of an arm vehicle. The power relay is used to or connect the power supply of the emergency lowering electric control box, but its electrical equipment still has the risk of failure, which cannot substantially solve the above problems

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