Compact dual boost valve system for a hydraulic damper

A compact dual boost valve system for a hydraulic damper comprising:

• a piston assembly of the hydraulic damper, the piston assembly comprising:
• a damper rod;
• a boost post coupled to the damper rod on a first end of the boost post, the boost post comprising a central chamber extending along an axis of the boost post with an inlet orifice located a second end of the boost post and extending into the central chamber;
• a main piston coupled around the boost post;
• a compression deflecting disc shim stack coupled around the boost post on a compression side of the main piston for compression damping;
• and
• a rebound deflecting disc shim stack coupled around the boost post on a rebound side of the main piston for rebound damping;
• a pilot stage comprising a proportional pressure relief poppet valve coupled within a damper rod of the hydraulic damper, the poppet valve comprising:
• a poppet coupled to an armature retained within a cartridge, the poppet and the armature guided by a bearing surface of the cartridge;
• a poppet orifice located at the second end of the boost post and extending into the central chamber, wherein the poppet is biased against the poppet orifice by a poppet spring;
• and
• a bobbin carrying a solenoid coil coupled around the cartridge, the solenoid coil operating between a zero-power state and a 100% power state, wherein a powered state above the zero-power state reduces an amount of force the poppet applies to the poppet orifice, wherein the reduction in the amount of force increases until sufficient power is applied to overcome a spring force of the poppet valve reaching the 100% power state;
• a compression main stage comprising a compression damping boost valve assembly, the compression damping boost valve assembly comprising:
• a compression boost valve coupled around the boost post on a compression side of a main piston of the hydraulic damper, wherein the compression boost valve is biased against the compression deflecting disc shim stack by a boost valve compression spring;
• and
• a compression boost valve chamber coupled to the central chamber by a compression feed orifice;
• and
• a rebound main stage comprising a rebound damping boost valve assembly, the rebound damping boost valve assembly comprising:
• a rebound boost valve coupled around a boost nut, the boost nut coupled to the second end of the boost post, wherein the rebound boost valve is biased against the rebound deflecting disc shim stack by a boost valve rebound spring;
• and
• a rebound boost valve chamber fluidly coupled to the central chamber by a boost nut rebound feed orifice extending through the boost nut that interfaces with a boost post rebound feed orifice extending from the central chamber, wherein during a compression event at the zero-power state:
• the poppet is biased against the poppet orifice;
• the poppet valve operates to equalize pressure in the compression boost valve chamber and the rebound boost valve chamber with an upstream damper pressure to generate high levels of hydraulic pressure across the main piston until a blow-off pressure of the poppet valve is reached;
• and
• opening the poppet with the high levels of hydraulic pressure and generating a pressure drop across the inlet orifice and the poppet orifice in response to hydraulic flow through the poppet valve after the poppet valve opens.

A method of boosting damping a hydraulic damper, the method comprising:

• providing a compact dual boost valve system coupled to a piston assembly of the hydraulic damper, the compact dual boost valve system comprising:
• a pilot stage comprising a proportional pressure relief poppet valve coupled within a damper rod of the hydraulic damper, the poppet valve comprising:
• a poppet coupled to an armature retained within a cartridge, the poppet and the armature guided by a bearing surface of the cartridge;
• a poppet orifice located at the second end of the boost post and extending into the central chamber, wherein the poppet is biased against a poppet orifice by a poppet spring;
• and
• a bobbin carrying a solenoid coil coupled around the cartridge, the solenoid coil operating between a zero-power state and a 100% power state, wherein a powered state above the zero-power state reduces an amount of force the poppet applies to the poppet orifice, wherein the reduction in the amount of force increases until sufficient power is applied to overcome a spring force of the poppet valve reaching the 100% power state;
• a compression main stage comprising a compression damping boost valve coupled on a compression side of a main piston of the hydraulic damper;
• and
• a rebound main stage comprising a rebound damping boost valve coupled on a rebound side of a main piston of the hydraulic damper, the poppet valve in fluid communication with the compression damping boost valve assembly and the rebound damping boost valve assembly;
• performing a compression event in the zero-powered state during operation of the hydraulic damper with the poppet biased against the poppet orifice;
• equalizing pressure in the compression damping boost valve assembly and the rebound damping boost valve assembly with an upstream damper pressure in response to the poppet valve in the closed position to generate high levels of hydraulic pressure across the main piston until a blow-off pressure of the poppet valve is reached;
• and
• opening the poppet valve with the high levels of hydraulic pressure and generating a pressure drop across an inlet orifice and the poppet orifice in response to hydraulic flow through the poppet valve after the poppet moves away from the poppet orifice.