Clearance control method of symmetrical balance-type free piston compressor

Abstract

The invention discloses a symmetrical balance-type free piston compressor, in particular to a clearance control method of a symmetrical balance-type free piston compressor, which comprises the following steps of: (1) setting a target clearance H and an initial steering position S on a control device; (2) confirming the steering position Sn of the same gas cylinder piston in the current compression period Tn according to delta Hn; (3) sending a steering instruction to a hydraulic device according to the Sn and the gas cylinder piston position signal measured by a displacement sensor; and (4) measuring the practical endpoint position of the current compression period Tn by the displacement sensor, calculating a practical clearance Hn. before the step (2) of the current compression period orafter the step (4) of the last compression period Tn-1, calculating the gas correction value delta Hn of the gas cylinder piston in the current compression period Tn according to H and the practical clearance Hn-1 of the last compression period, wherein the steering position of the first compression period T1 is S. By compensating H, the invention prevents the practical clearance from increasing with a pressure difference and improves the efficiency of the compressor.

Description

technical field [0001] The invention relates to a symmetrically balanced free-piston compressor, in particular to a clearance control method for a symmetrically balanced free-piston compressor. Background technique [0002] Symmetrically balanced free piston compressors usually include two or more cylinders symmetrically arranged on both sides of the oil cylinder. The compressor can be a one-stage compression compressor, and the above-mentioned cylinders are the compression cylinders; A cylinder is divided into two compression cylinders by the cylinder piston. By analogy, when both ends of the hydraulic cylinder of the compressor are coaxial and symmetrical in series with multiple cylinders, each cylinder is separated by a partition, and each cylinder has a cylinder piston that is divided into two compression chambers, each cylinder piston and the oil cylinder piston. The same piston rod is fixedly connected and can move freely together to become a multi-stage compression c...

AI Technical Summary

Problems solved by technology

However, the above-mentioned various types of clearance air volume adjustment devices are mainly adapted to the characteristics of forced air intake and exhaust inherent in the rigid drive mode of the mechanical connecting rod of the traditional compressor, and the gas pressure difference has no effect on the piston stroke.

For valve-distributed free-piston compressors, the unique movement stroke is variable and not fixed, so that the traditional clearance adjustment method cannot be implemented for this type of compressor or the cost is too high and the economy is not good.

Therefore, at present, this type of free-piston compressor that adopts valve distribution type has difficulty in clearance control. Existing similar models adopt extensive control such as proximity switch plus back pressure damping, and the control accuracy is not good. High, resulting in large changes in the actual operating clearance, which restricts its actual compression efficiency and poor market acceptance

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