Hydraulic valve lifter

Claim 2

A self-adjusting hydraulic valve lifter including an outer member of cylindrical cup shape closed at one end by a head and provided with a cylindrical recess at its opposite end to receive the stem of a valve, said head having a central boss integral therewith extending axially into said recess, said boss having a stepped bore therein including a first bore of a predetermined diameter extending from the free end of said boss and a second bore of a larger diameter, said first bore and said second bore meeting coaxially with an intervening radial extending shoulder, a plunger of cylindrical cup shape journalled for reciprocal movement in said first bore of said outer member in oppositely presenting relation to said outer member, said plunger having a cylindrical recess extending from one end and a head closing the opposite end thereof, said plunger being of an axial length such that the closed end of said inner member extends axially outward of said first bore from said boss and the open end of said plunger extends into said second bore, said plunger defining with the peripheral surface around said second bore and the interior surface of said head within said outer member a fluid chamber, spring means positioned in said fluid chamber for abutment against said plunger and said outer member to normally bias said plunger in one axial direction relative to said outer member and, oil supply passage means including an O-ring valve for supplying and maintaining a body of hydraulic fluid in said fluid chamber, said oil supply passage means including at least one supply channel means in said outer member and at least one supply passge in communication with a V-shaped annular groove opening into said fluid chamber, said O-ring valve being positioned in said Vshaped groove for controlling the one-way flow of fluid from said supply passage to said fluid chamber.

Claim 3

A self-adjusting hydraulic valve lifter according to claim 1 wherein said V-shaped groove is in the outer peripheral surface of said plunger adjacent to the open end thereof and said O-ring is of an external diameter whereby, with said O-ring valve positioed in said V-shaped groove, the outer periphery of said O-ring valve will extend radially outward of the nominal outside diameter of the plunger to provide a shoulder on said plunger extending into said second bore whereby to limit axial movement of said plunger by engagement of said O-ring valve with said shoulder, and wherein said oil supply passage means further includes passage means in said plunger positioned in communication with said supply channel means in said outer member and with said supply passage, and wherein said supply passage is in said plunger.

Claim 4

A self-adjusting hydraulic valve lifter in accordance with claim 1 wherein said V-shaped groove is provided in the inner peripheral wall forming said second bore in said outer member, said V-shaped groove and said O-ring valve positioned therein being of such a diameter so as to be out of interference relationship with said plunger upon reciprocation of said plunger within said outer member.

Claim 5

A self-adjusting hydraulic valve lifter according to claim 1 wherein said V-shaped groove is in said head of said outer member at the axial end of said second bore in said boss, said V-shaped groove being concentric with said second bore, said supply passage extending axially in said head of said outer member and, wherein said valve lifter further includes a valve disc retainer positioned between said spring and said head in position to limit axial movement of said O-ring valve.

Claim 6

A self-adjusting hydraulic valve lifter according to claim 3 further including a retainer means positioned in an annular groove in the outer peripheral surface of said plunger adjacent the open end thereof to extend radially outward of said plunger into said second bore for engagement against said shoulder whereby said plunger, said O-ring valve and said spring are retained in unit assembly with said outer member.

Claim 7

A self-adjusting hydraulic valve lifter according to claim 4 further including a retainer means positioned in an annular groove in the outer peripheral surface of said plunger adjacent the open end thereof to extend radially outward of said plunger into said second bore for engagement against said shoulder whereby said plunger, said O-ring valve and said spring are retained as a unit assembly within said outer member.

Claim 8

In an overhead valve and camshaft engine having a valve with a generally upwardly extending valve stem, the housing of the engine having a lifter guide bore therein concentric with the valve stem and an engine oil supply passage extending to the lifter guide bore, a cam spaced above the valve stem and, a hydraulic valve lifter interposed between the vale stem and the cam; said hydraulic valve lifter comprising an inverted cup-shaped outer member reciprocable in the lifter guide bore, said outer member having a central, lower bore extending from its lower end and a larger upper bore meeting said lower bore coaxially with an intervening shoulder and a head closing off the upper end of said outer member, said outer member further having an oil supply passage means extending from said lower bore to the outer periphery of said outer member in position to receive oil from the engine oil supply passage, an oppositely presented, cup-shaped, plunger having a closed head at its lower end, said plunger being reciprocably received in said lower bore with its upper end extending into said upper bore to define therewith a fluid chamber, said plunger having a V-shaped groove in the outer periphery thereof opening into said fluid chamber and a passage means therein opening at one end into the apex of said V-shaped groove and terminating at its other end in a side port in communication with said oil supply passage means in said outer member, an O-ring valve positioned in said V-shaped groove, said O-ring valve serving as a one-way check valve to control oil flow from said V-shaped groove into said fluid chamber and also serving as a shoulder extending radially outward from said plunger to limit axial movement of said plunger in one direction by engagement of said O-ring valve with said shoulder in said outer member and, a spring positioned in said fluid chamber to abut against said outer member and said plunger for normally maintaining said head of said outer member abutting the cam and said closed head of said plunger abutting the valve stem.

Claim 9

In an overhead valve and camshaft engine having a valve with a generally upwardly extending valve stem, the housing of the engine having a lifter guide bore therein concentric with the valve stem and an engine oil supply passage extending to the lifter guide bore, a cam spaced above the valve stem and, a hydraulic valve lifter interposed between the vale stem and the cam; said hydraulic valve lifter comprising an inverted cup-shaped outer member reciprocable in the lifter guide bore, said outer member having a central, lower bore extending from its lower end and a larger upper bore meeting said lower bore coaxially with an intervening shoulder and a head closing off the upper end of said outer member, said outer member further having an oil supply passage means extending from said lower bore to the outer periphery of said outer member in position to receive oil from the engine oil supply passage, an oppositely presented, cup-shaped, plunger having a closed head at its lower end, said plunger being reciprocably received in said lower bore with its upper end extending into said upper bore to define therewith a fluid chamber, said plunger having a V-shaped groove in the outer periphery thereof opening into said fluid chamber and a passage means therein opening at one end into the apex of said V-shaped groove and terminating at its other end in a side port in communication with said oil supply passage means in said outer member, an O-ring valve positioned in said V-shaped groove, said O-ring valve serving as a one-way check valve to control oil flow from said V-shaped groove into said fluid chamber and also serving as a shoulder extending radially outward from said plunger to limit axial movement of said plunger in one direction by engagement of said O-ring valve with said shoulder in said outer member and, a spring positioned in said fluid chamber to abut against said outer member and said plunger for normally maintaining said head of said outer member abutting the cam and said closed head of said plunger abutting the valve stem.