Abstract: A rotary vacuum pump includes a housing defining a pump chamber therein and a rotor extending through a first axial end panel into the pump chamber and carrying at least one vane for rotary movement of the vane within the pump chamber. The rotor comprises an annular axial end face configured to seal against a corresponding contact surface of a second axial end panel. An annular groove for reducing noise generation of the rotary vacuum pump during operation is formed at the annular axial end face of the rotor and/or the contact surface of the second axial end panel.

Abstract: A vacuum pump suitable for mounting to an engine includes a casing, a cavity in the casing having with an inlet and an outlet, a moveable member arranged for rotation inside the cavity, wherein the movable member is movable to draw fluid into the cavity through the inlet and out of the cavity through the outlet so as to induce a reduction in pressure at the inlet, an oil supply conduit for supplying oil from a reservoir to the cavity, and a check valve having a check valve body arranged in the oil supply conduit. The check valve meters the oil flow to the cavity dependent on an oil pressure so that on exceeding an upper oil pressure threshold the supply of oil to the cavity is stopped by means of the check valve.

Abstract: A rotary vacuum pump includes a housing defining a pump chamber therein and a rotor extending through a first axial end panel into the pump chamber and carrying at least one vane for rotary movement of the vane within the pump chamber. The rotor comprises an annular axial end face configured to seal against a corresponding contact surface of a second axial end panel. An annular groove for reducing noise generation of the rotary vacuum pump during operation is formed at the annular axial end face of the rotor and/or the contact surface of the second axial end panel.

Abstract: A vacuum pump suitable for mounting to an engine includes a casing, a cavity in the casing having with an inlet and an outlet, a moveable member arranged for rotation inside the cavity, wherein the movable member is movable to draw fluid into the cavity through the inlet and out of the cavity through the outlet so as to induce a reduction in pressure at the inlet, an oil supply conduit for supplying oil from a reservoir to the cavity, and a check valve having a check valve body arranged in the oil supply conduit. The check valve meters the oil flow to the cavity dependent on an oil pressure so that on exceeding an upper oil pressure threshold the supply of oil to the cavity is stopped by means of the check valve.