A Proportional Metering Oil Needle with Load Pressure Displacement Feedback

Abstract

The invention discloses a proportional metering oil needle for load pressure displacement feedback, which adopts a double-movable cylinder body of a valve sleeve and a valve core and a hollow oil needle structure with a constraint spring, and adapts the load fluctuation by designing the spring stiffness to make the metering oil needle output The flow rate is basically constant, and only the external mechanism controls the displacement of the valve sleeve body to achieve the purpose of flow ratio adjustment. The spring seat of the metering oil needle is rigidly connected with the outer cylinder, the adjusting bolt can adjust the spring preload, and the oil needle is supported by the spring. The external drive mechanism adjusts the position of the inner cylinder to control the opening of the oil needle. When the position of the inner cylinder remains unchanged, the oil needle changes the expansion and contraction amount through the spring to balance the load pressure, so that the metering oil needle moves in a small range to realize the fine adjustment of its opening. The spring stiffness is designed according to the flow equation, so that the change of the opening offsets the change of the flow area caused by the pressure difference fluctuation. The invention realizes the accurate proportional control of the flow rate, and simultaneously simplifies the structure of the metering device containing the oil needle, and has great practical value.

Description

technical field [0001] The invention relates to a metering oil needle, in particular to a proportional metering oil needle with load pressure displacement feedback. Background technique [0002] Metering devices, as one of the important components of hydraulic or fuel systems, have been widely used in many fields such as industry, agriculture, national defense, food, and medical treatment. The metering needle is a key component of the metering device, and its structure and characteristics have a direct impact on the flow control effect. With the continuous improvement of the control accuracy and response speed requirements for hydraulic or fuel flow, especially the high-performance metering technology under the condition of small flow and small disturbance is one of the important key issues that need to be solved urgently. [0003] The working principle of the traditional metering needle is mainly to control the pressure difference between the inlet and outlet to keep const...

AI Technical Summary

Problems solved by technology

The traditional metering needle adopts the flow control method of maintaining a constant pressure difference and adjusting the opening area of ​​the needle. There is no literature report on the nested double-cylinder pressure-sensitive metering needle.

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