Hydraulic cylinder capable of automatically controlling displacement and hoist

Abstract

The invention provides a hydraulic cylinder capable of automatically controlling displacement and a hoist. The hydraulic cylinder comprises a cylinder body and further comprises a piston movably arranged in the cylinder body; the piston is fixedly connected with a piston rod; a magnetic displacement sensor is arranged at the end of the piston rod; a hole which penetrates through the piston and communicates with a rodless cavity is formed in the piston rod; the magnetic displacement sensor is fixedly connected with a detection rod, and the detection rod is located in the hole; a fixing rod is further arranged, one end of the fixing rod is fixedly connected with the bottom of the rodless cavity of the cylinder body, and the other end of the fixing rod is located in the hole; and a magnetic ring is arranged at the end of the fixing rod and connected with the detection rod in a sleeving mode, and relative displacement between the piston and the cylinder body is detected through relative movement of the detection rod and the magnetic ring. In the hoist, the cylinder body of a hydraulic cylinder is fixedly connected with a gate, a rack is arranged above the gate, and the piston rod is connected with the rack; and the end of the piston rod of the hydraulic cylinder is located at the top of the rack. By means of the structure, the magnetic displacement sensor is prevented from being soaked in water for a long time, and on-site maintenance and replacement are facilitated.

Description

technical field [0001] The invention relates to the field of headstock machines, in particular to a hydraulic cylinder with automatic displacement control and a headstock machine. Background technique [0002] With the widespread application of hydraulic hoists in domestic water conservancy and hydropower projects, upside-down hydraulic hoists are often used to vertically open and close working gates and emergency gates in urban river landscape projects and lake drainage pumping stations. In order to detect the opening value of the gate opening and closing, it is necessary to set a displacement sensor for stroke detection, especially the double lifting point hydraulic hoist also needs to obtain the piston displacement value of the two oil cylinders to synchronously control the deviation value on both sides of the gate to avoid the gate Jamming due to out of sync on both sides. The piston rod of the upside-down hydraulic hoist cylinder usually faces upwards, and the top end ...

AI Technical Summary

Problems solved by technology

[0003] In the prior art, the following schemes are usually adopted in order to detect the displacement of the hydraulic cylinder: 1. An external steel wire rope displacement sensor. The waterproof performance in this scheme is relatively poor. Ingress of impurities is prone to jamming or chaotic grooves

Once there are aquatic plants or branches and miscellaneous trees in the water, it is easy to be entangled on the wire rope, and the wire rope is not pulled up normally, resulting in signal acquisition failure

2. The built-in wire rope displacement sensor has many mechanical parts, and the measurement accuracy is greatly affected by the mechanical parts

Laser displacement sensors are susceptible to temperature drift, which affects the accuracy of measurement accuracy and repeatability

Especially when used in an upside-down hydraulic hoist, the high water level will cause the laser sensor to fail to detect any data from the moving gate or cylinder block

4. Ultrasonic displacement sensor, ultrasonic displacement sensor is the same as laser displacement sensor, there are problems of precision and measurement accuracy

However, in this scheme, the magnetic ring and the sensor rod are blocked by the outer wall of the piston rod, and the measurement accuracy is affected

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