A vane fluid pump for a vehicle component is provided with an inner rotor supported within a cam. The inner rotor has an outer wall extending between first and second end faces, the outer wall defining a series of slots spaced apart about the outer wall to provide a series of outer wall sections. One of the wall sections defines a groove. Another of the wall sections is independent of grooves or is ungrooved. The pump has vanes positioned within respective slots of the inner rotor and extending outwardly to contact the continuous inner wall of the cam. The groove on the inner rotor is configured fluidly couple with a notch on the housing to provide fluid flow to the discharge port from an upstream pumping chamber to disrupt harmonics during operation to reduce pressure ripples and associated tonal noise.

On a plane orthogonal to the rotation shaft, an upper muffler chamber has a plurality of flared portions that are flared from a center of a rotation shaft toward between penetrating bolts and a plurality of small-diameter portions that connect between the flared portions, are apart from penetrating bolts, and are formed on a center side of the rotation shaft from the penetrating bolts. A muffler outlet is provided in each flared portion. A second outlet and a refrigerant path hole of an upper end plate are positioned on an inside of one of a plurality of flared portions, and an opening area of the muffler outlet of one flared portion is greater than an opening area of the muffler outlet of each of the other flared portions.

A system, apparatus, and method for attenuating pulsations in a pumping system.

The present application provides a slide valve, wherein the slide valve is configured to regulate a load of a twin-screw compressor. The slide valve comprises a slide valve body, wherein the slide valve body has a connecting end and a free end, the connecting end is configured to connect to a slide valve connecting rod of the twin-screw compressor, and the slide valve is driven to slide by the slide valve connecting rod. A cavity is formed in the free end of the slide valve body, and the slide valve has a passage configured to fluidly couple the cavity with an external fluid to reduce air flow pulsations on a suction side of the twin-screw compressor and thereby reduce overall air flow pulsations in the twin-screw compressor.