Hydraulic time-delay double-stage braking hoister hydraulic station

Abstract

The invention relates to a hydraulic station for a hydraulic delay secondary braking hoister. An electric motor drives an oil pump, an oil passage of the oil pump is connected with a proportional relief valve, and an oil passage of the proportional relief valve is connected with a shuttle valve which is connected with a brake through a first electromagnetic reversing valve; an oil passage of the first electromagnetic reversing valve communicated with the brake is provided with a one-way throttle valve, and two ends of the one-way throttle valve are connected with a power accumulator and a hydraulically operated directional control valve respectively; two ends of a one-way speed control valve are connected with control oil ports of the relief valve and the hydraulically operated directional control valve respectively, and an oil passage of the one-way speed control valve is communicated with an oil passage of the shuttle valve; the relief valve is connected between the oil passage of the electromagnetic reversing valve communicated with the brake and the oil passage of the one-way speed control valve communicated with the electromagnetic reversing valve; and a common oil passage ofthe one-way speed control valve and the relief valve is connected with a second brake through a third electromagnetic reversing valve. The hydraulic station has simple adjustment to the primary braking pressure, eliminates pressure drop phenomenon when the primary braking oil pressure is delayed, and ensures the reliability of the secondary braking performance.

Description

technical field [0001] The invention particularly relates to a hydraulic time-delay secondary brake hoist hydraulic station used for hoist safety braking by hydraulic technology for mine winches, cable cars for docks, cableways, etc. Background technique [0002] Various lifting and transporting machinery are usually completed by hydraulic delay secondary braking. Hydraulic time-delay secondary braking is one of the important performances of various lifting and transportation machinery. If the winch used for various lifting and transportation machinery does not have secondary braking, the fast-moving winch will encounter a sudden power failure. , All the brakes are suddenly locked and braked, which will shake the wire rope, and the people in the winch are easily injured. If the wire of the winch is broken, it will cause a major safety accident. At present, the hoist hydraulic station has two forms of electrical delay secondary braking and hydraulic delay secondary braking. ...

AI Technical Summary

Problems solved by technology

However, the effect of the secondary braking of the hydraulic station of the hydraulic delay secondary braking hoist still cannot reach the ideal state, mainly as follows: (1) The primary brake oil pressure drops greatly within the action time; (2) ) Since the primary brake oil pressure is set by the relief valve and the relief valve, and the pressure setting value of the relief valve is 0.2-0.3Mpa higher than the pressure relief valve pressure setting value, the adjustment of the primary brake oil pressure Complicated, it is necessary to coordinate the pressure reducing valve with the relief valve, which requires high technical requirements for the commissioning personnel; (3) When the primary brake oil pressure setting value is less than 2.5Mpa, its pressure retention is poor, causing delay time is short

Especially when the load carried by the winch is large and the slope of the winch is large, it is necessary to adjust the primary pressure to be lower than 2.5Mpa. There is still leakage in the oil storage, the delay time of the pressure holding of the hydraulic station is very short, and the system basically does not have a first-level brake. When a sudden power failure occurs, the brake will also be suddenly locked and the wire rope will vibrate, resulting in a safety accident.

Therefore, the current hydraulic delay secondary brake hoist hydraulic station has the disadvantages of unstable primary braking pressure and poor secondary braking performance.

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