초록 ▼

A combination high pressure accumulator/bypass valve assembly suitable for vehicle control systems such as anti-lock braking systems and traction control systems employs a stationary seal and a reduced part count favoring economy of manufacture and assembly, and eliminates the dynamic seal/light all

A combination high pressure accumulator/bypass valve assembly suitable for vehicle control systems such as anti-lock braking systems and traction control systems employs a stationary seal and a reduced part count favoring economy of manufacture and assembly, and eliminates the dynamic seal/light alloy interface, significantly reducing the potential for failure due to pump body/seal abrasion. A caged spring assembly further encourages ease of assembly.

대표청구항 ▼

A high pressure accumulator/bypass valve suitable for use in vehicle control systems, comprising: a body having a stepped bore providing a first diameter and a second diameter immediately adjacent one another, said second diameter being larger than said first diameter, a radially extending shoulder

A high pressure accumulator/bypass valve suitable for use in vehicle control systems, comprising: a body having a stepped bore providing a first diameter and a second diameter immediately adjacent one another, said second diameter being larger than said first diameter, a radially extending shoulder located at the step between said first and second diameters; a cylindrical piston element having a high pressure end and a low pressure end, the diameter of said low pressure end providing a sliding fit within said bore of said first diameter; a cylindrical collar concentric to said piston, said collar having an outer diameter and an inner diameter, said inner diameter of said collar providing a sliding fit onto said piston element, the end faces of said collar defining a high pressure face and a low pressure face; a stationary seal located in said bore of second diameter between said radially extending shoulder and said low pressure face of said collar in a stationary seal retainer space as thereby defined, said stationary seal sealingly engaging said piston element; a hollow cylindrical retainer having a closed high pressure end, an open end and an internal diameter; a prestressed coil spring receiving said piston element and having an inner diameter and an outer diameter, the ends of said spring bearing against said piston element and said high pressure face of said collar; the interior of said retainer and that portion of said stepped bore located on the high pressure side of said stationary seal defining a high pressure fluid reservoir; a high pressure fluid passage communicating with said high pressure fluid reservoir; a fluid bypass passage communicating with that portion of said stepped bore located on the low pressure side of said stationary seal; a relief flow groove in said piston element proximate said collar, the position and length of said relief flow groove selected so as to extend past said stationary seal when said piston element is driven beyond a fixed distance against the pressure of said spring by high pressure fluid allowing fluid from said high pressure reservoir to bypass said stationary seal, said relief flow groove positioned so as to prevent bypass of fluid from said high pressure reservoir when said piston element is not driven beyond said fixed distance.