Noise mitigating hydraulic control unit assembly for a vehicle braking system

A blow-off metering valve for a hydraulic control unit assembly of a brake system of a vehicle for reducing noise from a pump, comprising;

• a valve seat for being located in a bore of the hydraulic control unit assembly, the valve seat including a wall generally having a sleeve shape and extending about an axis and extending axially between a first end and a second end;
• the wall defining a passage extending axially between the first and second ends for transmitting a fluid through the valve seat;
• an annular flange extending axially from the second end of the wall toward the first end of the wall and tapering radially inwardly to define an annular flange;
• a blocking member axially aligned with the annular flange and axially movable toward and away from the annular flange for creating a seal to inhibit the flow of fluid through the passage of the valve seat when the blocking member engages the annular flange;
• a compression spring biasing the blocking member toward the annular flange, the compression spring including a plurality of windings, wherein the plurality of windings include a plurality of outer windings and a plurality of inner windings, wherein the outer windings have a smaller radius than the inner windings for eliminating spring stack and allowing fluid to more easily pass through the spring.

A hydraulic control unit assembly for controlling hydraulic brake pressure at a brake cylinder, comprising:

• a housing defining at least one bore defined by an inner wall extending between an inlet and an outlet, wherein the inlet is for being connected with a pump, and wherein the outlet is for being connected to a brake cylinder;
• a blow-off metering valve for reducing noise from the pump located in the bore, the blo-off metering valve including:
• a valve seat for being located in a bore of the hydraulic control unit assembly, the valve seat including a wall generally having a sleeve shape and extending about an axis and extending axially between a first end and a second end;
• the wall defining a passage extending axially between the first and second ends for transmitting a fluid through the valve seat;
• an annular flange extending axially from the second end of the wall toward the first end of the wall and tapering radially inwardly to define an annular flange;
• a blocking member axially aligned with the annular flange and axially movable toward and away from the annular flange for creating a seal to inhibit the flow of fluid through the passage of the valve seat when the blocking member engages the annular flange;
• a biasing element biasing the blocking member toward the annular flange;
• the annular flange terminating at a distal end being radially spaced from the wall;
• and
• the annular flange defining at least one flow channel for allowing fluid to bypass the blocking member when the blocking member engages the annular flange.