US3048156A - Submerged type hydraulic valve lifter - Google Patents

Description

1962 J. VAN SLOOTEN 3,048,156

SUBMERGED TYPE HYDRAULIC VALVE LIFTER Filed April 17, 1961 2 Sheets-Sheet l {NVENTOIL 43w; d 16w $70056 AT TORN EY Aug. 7, 1962 J. VAN SLOOTEN SUBMERGED TYPE HYDRAULIC VALVE LIFTER 2 Sheets-Sheet 2 Filed April 17, 1961 INVENTOR. fiwdlayovz? A TORNEY- United htates Ratch t a 048,156 'SUBMERGED TYPE HYDRAULIC VALVE LIFTER Louis J. Van Slooten, West Olive, Mich, assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed Apr. 17, 1961, Ser. No. 103,297 Claims. (Cl. 123--90) This invention relates to hydraulic valve lifters such as are used tor operating the valves of overhead valve type internal combustion engines, and particularly to the means for supplying such lifters with hydraulic fluid.

While it has long been common practice to supply such lifters with oil under pressure from the engine lubricating system, either via side ports in the lifter body and plunger from an engine oil gallery in the crankcase or cylinder block, or by gravity feed via the push rod from the rocker lubricating passages, the valve lifters in all successful such arrangements have necessarily included a push rod seat member for transmitting the thrust motion between the lower end of the push rod and the plunger of the lifter. The requirement of this additional part has added to the cost and weight of the valve lifter, and has the further disadvantage of tending to'inc-rease the necessary length of the lifter body and plunger since the transmission of thrust to the push rod with this arrangement necessarily occurs at the upper end of the plunger and sulficient lateral bearing area must be provided on the plunger and lifter body to maintain side loading pressures on these parts within acceptable limits for While attempts have been made to eliminate plunger, difliculty has been encounted in maintaining a satisfactory supply of air-free oil to the check valve controlled passage which leads through the plunger to the oil cushion chamber below it in the bottom of the lifter body. The high speed of lifter reciprocation under operating conditions tends to aerate the oil in the plunger and prevent its ready availability for supplying the check valve passage. While the crankcase structure forming the lifter guide bore can be extended upwardly to provide a larger storage reservoir for oil to be supplied to the plunger, such an expedient considerably increases the cost of'the engine, makes servicing of the litters more difficult, and requires special provisions for insuring an adequate head of oil above the lifter under all conditions of engine operation.

The desired objective of eliminating the requirement for the aforementioned push rod seat part is accomplished in a verysimple and economical manner in accordance with my invention through the use of a removable standpipe which surrounds the push rod. The standpipe can be easily mounted so as to seal at its lower end to the lifter bore shelf which projects laterally from the crankcase of the conventional engine. Adjacent its upper end the standpipe can be conveniently supported by a bracket, such as a stamping clamped to the top of the cylinder head in any desired manner.

If desired, the standpipe can be periodically refilled as to conduct the oil from the rocker oil passages 21 similar overflow port can be provided in the side of the push rod for the same purpose.

The invention will be more clearly understood from the following description, having reference to the drawings, wherein:

FIGRE l is a transverse sectional view through a portion of one side of an internal combustion V-type engine embodying one form of the invention.

FIGURE 2 is a fragmentary view similar to FIGURE 1, but'showing a slightly different arrangement or" the standpipe.

FIGURE 3 is an enlarged perspective view of the diaphragm shown in FIGURE 2.

FIGURE 4 is a fragmentary view similar to FIGURES 1 and 2, but showing a still further embodiment of the invention.

As shown in FIGURE 1, the invention is embodied in an internal combustion engine comprising a crankcase 1, integrally tormed with which is an engine working cylinder 2 extending upwardly at an angle to the vertical, it being understood that one or more additional such cylinders 2 may form one bank of a V-type engine and a similar bank of cylinders (not shown) are inclined oppositely to form the other half of the V. The engine is of the so-called overhead valve type in which each cylinder has a downwardly opening poppet valve 4 mounted in the cylinder head 3 to control a port 4 in the combustion chamber 5 above the power piston 6. The valve 4 is normally held in its closed position as shown by a spring 7 and openable against the biasing force of the spring by a valve rocker 8 journaled on a shaft 9 which is suitably supported on the cylinder head by one or more pedestals 10*. The driven end 11 of the rocker engages the upper end of a push rod 12 which extends toward the crankcase and seats at its lower. end

' in the plunger 13 of a hydraulic valve lifter designated necessary, with oil or other hydraulic fluid to be used in the lifter, a sliding laterally flexible seal being provided between the push rod and the standpipe adjacent its upper end. Alternatively, the'standpipe can be arranged to receive and store oil flowing thereinto along the push rod from the rocker lubricating system, the interior of the standpipe being bafiled to prevent undesirable agi-tation and surge of the oil therein in the vicinity above the lifter. By providing a side port in the standpipe intermediate its ends the head of oil therein can be maintained as desired, and if the push rod is made hollow generally by the numeral 14. The pluinger 13 is slidably reciproca-ble in the cup-shaped body of the lifter whose side Walls are indicated at 15 and its end Wall at 16. The end wall .16 of the lifter abuts the usual engine camshaft 17 and is slidably guided tor reciprocation thereby in a litter bore 18 formed in a shelf 19extending laterally of the crankcase from the working cylinder 2. The opposite corresponding hydraulic valve lifter associted with the other bank of the engine is indicated at 20. The interior of the lifter body below the plunger 13 forms an oil cushion chamber 21, to which oil may flow via a one-way passage 22 centrally through the plunger13, the one-way flow being effected by a check valve 23. Slots 24 formed in the plunger opposite the lower end of the push rod permit oil to enter the passage 22 from the interior of the plunger and the interior of the lifter body above the plunger.

Surrounding the push rod is a standpipe 25 which extends upwardly from the shelf 19 and/is sealed thereto adjacent the bore 18 by any suitable sealing means such as the O-ring 26. By extending the standpipe up through the push rod openings 27 and 28 in the cylinder block structure and head 3, respectively, an adequately large oil storage capacity is obtained for oil supplied to the lifter, and the end of the standpipe can be conveniently supported by a bracket 29 in the form of a stamping clamped to the top of the cylinder head'by the rocker pedestal ltl. In the particular engine shown, oil for lubricating the rocker is conducted through the gallery 3t formed by the hollow rocker seal 9. A pair of connecting passages 31 and 32 in the rocker connect its bearing surface on the shaft 9 with the upper end of the push rod 12, and the excess oil delivered thereby drains down the push rod into the standpipe 25 for supplying the hydraulic lifter. To prevent any execessive aoaazee agitation of the oil collected in the lower portion of the standpipe, there is provided a baille 33 extending inwardly from the internal wall surfaces of the latter and provided With a central opening 34 sufiiciently large to accommodate all movements of the push rod.

Instead of relying on the continuous oil fed from the valve rocker, the standpipe 25 may be periodically filled with the oil or other fluid to be used in the hydraulic lifter. In such case, a laterally flexible seal 35 in the form of a diaphragm may be inserted between the push rod and the inner wall surfaces of the standpipe as shown in FIGURE 2. Such diaphragm as best illustrated in FIGURE 3 is reinforced at its outer periphery by a rigid metal ring 35', which may be press-fitted into the standpipe 25, and its internal periphery is oppositely flanged as at 36 to effect a sliding seal on the push rod 12. Each such filling of the standpipe can be readily effected after removal of the push rod 12 and directing the oil or other fluid to be used through the central opening in the diaphragm.

Where desired to limit the head of oil within the standpipe, as supplied from the rocker oil passages 32 and 31, an overflow port 37 is provided in the side wall of the standpipe. This is illustrated in FIGURE 4. As also showvn therein, a hollow push rod 12 may be used to conduct the oil from the valve rocker, and an overflow side port 38 in the push rod serves to limit the head of oil obtainable.

Each of the various arrangements above described accomplishes the principal objective of enabling the push rod 12 to connect at its lower end directly with the plunger 13 of the lifter, obviating the requirement of a push rod seat to transmit the thrust between these two parts. A shorter and therefore less expensive hydraulic lifter results, together with all the advantages of submerged type lifter operation which is not dependent upon delay-s in pressure feeding from the engine lubricating system, yet avoids the additional weight and complication embodied in previous proposals for obtaining the necessary oil storage capacity by an enlargement of extension of the crankcase and cylinder structure.

While only three preferred embodiments of the invention have been disclosed, it is appreciated that numerous minor changes in the construction and arrangement of the parts may be made without departing from the spirit and scope of the invention as defined in the follow ing claims.

I claim:

1. In an internal combustion engine of the overhead valve type having a cylinder head, a valve operating rocker mounted on the head, an engine crankcase having a rocker driving camshaft therein spaced below the driven end of the rocker, a hydraulic valve lifter includ ing a cup-shaped body having its end wall abutting the camshaft and a plunger reciprocably slidable in said body, a shelf extending laterally from the crankcase and provided with a bore slidably guiding said body for reciprocation by the camshaft, a push rod thrustably connecting the plunger to the driven end of the rocker, said plunger having a oneway passage for introducing oil into the body below the plunger for thrustably supporti ing the plunger therein, means for conducting oil to the push rod at the driven end of the rocker, a removable standpipe defining an oil storage chamber surrounding the push rod above said lifter guiding bore, said standpipe having sealing means connecting it to the shelf a-djacent said bore, and a standpipe supporting bracket fixed to the upper end of the standpipe and to the cylinder head below the rocker, said standpipe having an internal baffle surrounding the push rod and spaced above said shelf.

2. In an internal combustion engine of the overhead valve type having a crankcase, a working cylinder extending generally upwardly therefrom, a cylinder head, a valve operating rocker mounted on the cylinder head, a camshaft rotatable in the crankcase laterally of the cylinder, said crankcase having a shelf extending laterally of the cylinder above the camshaft, said shelf having a bore extending therethrough, a hydraulic valve lifter including a generally cup-shaped body having an end wall abutting the camshaft and side walls slidably fitting said bore, an upwardly open generally cup-shaped plunger in said body, a push rod extending into and seated against the lower end of said plunger, said push rod extending into driving engagement at its other end with the rocker, said plunger having a close sliding fit with the internal surfaces of the body side walls and a check valve controlled passage accommodating one-way flow of fluid through the plunger toward said body end wall, said passage being open to the interior of said plunger and of said body above the plunger, and a removable standpipe surrounding the push rod and extending upwardly from said shelf, seal-ing means surrounding said lifter bore between said shelf and the lower end of said standpipe, and a bracket securing said standpipe to the engine above said shelf.

3. The invention of claim 2, wherein said rocker isprovided with an oil passage leading to the upper end of the push rod, said push rod being hollow and open at its upper end to said rocker passage and having a side port intermediate its ends for delivery of oil to said interior of the lifter body above the plunger via said standpipe.

4..The invention of claim 3, wherein said standpipe has a side port intermediate its ends through which oil therealbove within the standpipe is by-passed to the crankcase.

5. The invention of claim 2, wherein a laterally flexible diaphragm surrounds the push rod within the upper portion of the standpipe, said diaphragm having its outer periphery fixedly sealed to the internal wall surface of the standpipe and its inner periphery in slidable sealing engagement with the push rod.

References Cited in the file of this patent UNITED STATES PATENTS 1,993,875 Daub Mar. 12, 1935 2,025,836 Treiber Dec. 31, 1935 2,306,554 Morehouse Dec. 29, 1942 2,386,317 Jenny et a1. Oct. 9, 1945 2,657,679 Powell Nov. 3, 1953 2,667,149 Purchas et a1. Jan. 26, 1954

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