Double-arc gear pump

Abstract

The invention relates to a double-arc gear pump. A pump body is internally provided with a driving double-arc gear and a driven double-arc gear which are in instantaneous single-point meshing transmission; the driving double-arc line gear and the driven double-arc line gear are line gears provided with a plurality of line teeth; each linear tooth is provided with a tooth top, a transition curved surface and a tooth root which are connected in sequence; the tooth crest and the tooth root are in a conjugate arc tooth shape; the transition curved surface is tangent to the tooth root; the transition curved surface is provided with a contact line formed by a plurality of instantaneous meshing points; the contact line is a cylindrical spiral line; the pitch radius of the line gear is equal to the meshing radius of the contact line. The arc main gear and the arc auxiliary gear only have a contact point on the end face where the instantaneous meshing point is located, the two gears on the other end faces are in a disengaged state, and a closed oil trapping volume cannot be formed, so that the oil trapping phenomenon in the gear pump is avoided, the phenomenon that the instantaneous meshing line continuously changes is avoided, and the service life of the gear pump is prolonged. The constant radial leakage at the gear meshing position in the meshing process is guaranteed, and the stability of the output flow of the gear pump is improved.

Description

technical field [0001] The invention relates to the technical field of fluid machinery, in particular to a double arc gear pump. Background technique [0002] External gear pumps are widely used in fluid transmission, automation and aerospace fields. Among them, the most widely used tooth shape is the involute tooth shape, but the gear pump with this tooth shape will cause oil trapping during the transmission process, which will cause the gears, shafts and bearings to be subjected to a large radial force, and will also damage the gears. The dynamic performance such as the output flow and output pressure of the pump will have a serious impact. [0003] The conventional method to alleviate the oil trapping phenomenon is to open different forms of pressure relief grooves or pressure relief holes, but it cannot fundamentally eliminate the oil trapping phenomenon of the gear pump, and it will also increase the difficulty of manufacturing the gear pump. [0004] The prior art di...

AI Technical Summary

Problems solved by technology

[0005] It has the following technical problems: in the process of a pair of teeth from entering meshing to exiting meshing, the length of the instantaneous meshing line will inevitably become longer first and then shorter, resulting in the radial leakage of the gear meshing first becoming smaller After that, it will become larger, which will cause the output flow of the gear pump to fluctuate, which is not conducive to the application of the gear pump in the hydraulic system of aerospace engines that require low output flow pulsation.

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