US2873729A

US2873729A - Self-contained type hydraulic valve lifter

Info

Publication number: US2873729A
Application number: US470305A
Authority: US
Inventors: Louis J Van Slooten
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1954-11-22
Filing date: 1954-11-22
Publication date: 1959-02-17
Anticipated expiration: 1976-02-17

Description

\U\ r Feb. 17, 1959 .1. VAN SLOOTEN ,8 9. S ELF-CONTAlNED' TYPE HYDRAULIC VALVE LIFTER Filed Nov. 22, 1954 INVENTOR United States Patent SELF-CONTAINED TYPE HYDRAULIC VALVE LIFTER Louis J. Van Slooten, Holland, Mich., assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application November 22, 1954, Serial No. 470,305

9 Claims. (Cl. 123-90) This invention relates to automatically extensible thrust transmitting devices such as hydraulic valve lifters used in the valve trains of internal combustion engines and the like, and particularly to such devices of the self contained type in which the fluid is sealed within the assembly with no provision for its replenishment from any external source during operation.

It is the principal object of the invention to provide an improved lifter device of the aforementioned type employing a cylinder, a plunger and a bellows seal between the thrust transmitting end of the plunger and its associated end of the cylinder.

A more specific object of the invention is to provide such a sealing construction in the form of a metallic tubular bellows having piston and cylinder connecting means associated with the respective ends of the bellows which serve in a particularly advantageous manner to support the adjacent bellows pleats against excessive localized bending stresses in operation.

A further object of the invention is to form the connecting means between the cylinder member and its associated end of the bellows with a rigid portion which serves both to protect the bellows from external injury and to prevent excessive movement of its piston associated end in the direction tending to collapse the bellows.

- A still further object of the invention is to provide a bellows sealed hydraulic valve lifter which comprises a minimum number of parts of light weight and simple design which can be economically manufactured and assembled into a unit unsusceptible to damage in handling and capable of long service in operation.

The means by which these and other objects of the invention are attained will be more clearly understood from the following description of a preferred embodiment, having reference to the drawing wherein:

Figure 1 is a sectional view of a portion of an internal combustion engine having a valve operating train incorporating my improved lifter device.

Figure 2 is an enlarged sectional view similar to Figure 1, showing the internal construction of the lifter device.

Referring now in detail .to the drawing, there is shown in Figure 1 an engine cylinder block and crankcase structure designated generally by the numeral 1 in which is located a working cylinder 2 having the usual piston 3. Closing the upper end of the cylinder 2 and forming a combustion chamber 4 above the piston is a cylinder head 6. 'At 7 is a poppet valve controlling communication between a cylinder head port 8 and the combustion chamber 4 and having a stem 9 slidably mounted for reciprocation in the cylinder head. In conventional manner, reciprocal movements of the valve 7 are effected by rotation of a cam 11 which is suitably supported in they crankcase 1 and driven in timed relation with movements of the piston 3. Completing the valve operating train, I have shown my lifter 12 operatively engaging the cam 11 and slidably supported for reciprocation in a lifter ice bore 13 formed in the crankcase 1. Upward movements of the lifterare transmitted by the usual push rod 14 to an adjusting screw 16 fixed in one end of the rocker 17, which latter is arranged to oscillate about an axis represented by the rocker shaft 18 suitably supported on the cylinder head 6, the other end of the rocker being in driving engagement with the upper end of the valve stem 9. A valve return spring 19 having one end secured to the valve stem and its other end seated against the cylinder headserves to maintain the valve in closed position as illustrated in Figure l.

As shown in Figure 2, the lifter 12 comprises telescoping cup-shaped cylinder and plunger members 21 and 22 arranged in nesting relation. Between the closed end of the cylinder 21 and the adjacent end of the lifter plunger 22 is a fluid pressure chamber 23 which is normally maintained filled with fluid for transmitting thrust from the cylinder to the plunger during opening movements of the engine valve 7. This pressure chamber includes a well- 24 which opens upwardly into an enlarged diameter portion 26 of preferably greater diameter than the bore 27 of the cylinder and extending upwardly on the lower end of the plunger outer periphcry. The lower end of the plunger has an extension 28 of reduced diameter forming a shoulder 29 at its juncture with the main body to the plunger. Loosely journalled on the extension 28 and having an external flange 31 rotatably seated against the shoulder 29 is a cup-shaped cage member 32 whose end wall is provided with one or more apertures 33 providing communication between the interior of the cage member and the portion of the chamber 23 externally thereof. The side walls of the well 24 loosely fit the plunger biasing spring 34 whose upper end loosely embraces the cage member 32 and maintains the flange 31 of the cage seated against the shoulder 29 of the plunger. Extending through the end or bottom wall of the plunger and its extension 28 is .a fluid supply passage 36, through which fluid may pass to the pressure chamber 23 from reservoir 35 interiorly of the hollow plunger. A check valve accommodating such flow but preventing flow in the reverse or upward direction through the passage 36 is provided in the form of a ball 37 which is of larger diameter than the passage 36. The seat ,for this ball 37 is formed by the lower end of the plunger extension 28 and when the ball is in engagement with this seat and the cage flange 31 is in abutment with, the plunger shoulder. 29 only a predetermined small clearance (on the order of .004-.008 in.) exists between the ball and the bottom wall of the cage member.

Above the shoulder 29 the plunger side walls 40 have a close sliding fit in the cylinder bore 27. The cylinder bore 27 extends only a limited distance above the pressure chamber enlargement 26, the upper side walls 41 of the cylinder being relieved on their internal periphery to form an annular extension 42 of the reservoir 35. The piston side walls 43 have their external periphery also relieved adjacent the open end and are provided with one or more apertures 44 interconnecting the reservoir 35 and its extension 42. The upper end of the plunger side walls 43 terminate within the lower end of the reservoir extension 42, and resting on the open end of the plunger is a push rod seat member 45 which serves to transmit plunger thrust to and forms a lower seat for the push rod 14. This seat member 45 has a depending portion 46 extending a short distance into and having a slip fit with the plunger upper side walls 43, the plunger thrust being taken by a shoulder 47 surrounding this depending portion 46. The upper surface of the seat member, including its central push rod seating surface 48 which is preferably made concave as shown, and

the surrounding annular surface 49 which is preferably made flat are both imperforate and form part of the sealing means preventingrescape offluid from theyliften device.

Also included in the sealing means is a rigid-member 50, conveniently formed as-a sheet metal stamping, and including a tubular portion 51 and a flangeportion SZ. The tubular portion 51 is of a diameter larger thanthe push rod, 14 and extends coaxially of the cylinder a sufficient distance inwardly thereof to serve as aplunger stop means limiting outward movement of the plunger by abutment with the annularsurface 49'. The flange 52 which connects the upper end of thisitubulargportion to, the open end of the cylinder, as by a spinningror any other suitable sealed connection 53,: forms-.a;pocket 54 facing the annular surface 49.-

- Adjacent one. marginal extremityofitherportion of the pocket 54 are the opposite ends of a tubular bellws 56 which loosely surrounds the tubular portion-51; and :com

pleting the sealed connection between the-cylinder open,

end and the push rod seat 451111? upper and, lower annular bodies 57 and, 58 of solder or other;rela tively 11OW' melting point metal in which the longitudinally out-turned: upper and lower flanged ends 59 zandgtl, of the bellows It will be observed; thatthe lower end pleat 61 ofthe bellows abuts the flatannularsurface- 49- are imbedded.

adjacent the recess 55, and the solderSS-in this'recess is of such-depth-that its upper sunface-isr-flush withthe;

annulansurfaceil towcooperate in gsupporting the end Pleat 61.

avoided and its resultant-fatigue failure has beenpracti cally-.eliminated. Ill-addition, the arrangement whereby the bellows end fianges 60- and 59 are 'imbedded in thesolder further=ensures that all endwise loading of the, bellows is ;-substantially coaxial, whether in tension or'-. compression, The provision of the recess SSand -the pocket 54 -facilitate-convenient assembly of thebellows to the push rod seat 45 and the rigid member 50 in production-since the depjosits =0f solder can beinitially installed int-each, after which first one end of the bellows andthen; the other maybe imbeddedwhile maintaining the .solder- The spinning or crimping; of the sheet metal flange toforrn the connection -53;with the.

in molten condition.

cylindenis preferably doneafter completing the Sub-2&- sembly-of the last three mentioned parts.

The tubular portion 51, in addition to serving as, a stop.,li1niting contraction of the bellows, shields the internal periphery of-rthe bellows from external damageduring-handling of the lifter? and during insertion and removal of the push rod learn the engine. The tubularportion 5l' also serves to support the bellows against any abnormal: lateral deformation resulting -from i an excessive pressure developing within the reservoir and its extension eliand the flange portion 52 of thecsheet metal/stamping serves to cooperate with the tubular. portion in shielding the bellows upperrend against damage,

in handling.

While only a single preferred'embodiment of the invention has 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 Similarly, the upper-body .of, solder .SZ -is de posited to such a depth inthe pocket 54=as toprovide (a; fiat surface-62 adjacent the bellowsend: flange 5940, abuttably support the upper end;pleat 63 ofthmbellovvs;

4 and scope of the inventionas defined in the following claims.

I claim:

1. In an automatically extensible and contractible thrust transmitting device of the self-contained-fluid typehavinga cylinder and a plunger reciprocable therein, a body'of fluid within the cylinder, said'cylinder and plunger having means respectively movable therewith presenting facing longitudinally spaced apart surfaces, one of said surfaces being formed at least in part by a body of relatively low melting point material, and a bellows expandible longitudinally of the cylinder-having at least one of its ends defined by a surface facing and parallel to said one surface .andaflange, said bellows surface being in abutment with said one surface and said flange being embedded in said material.

2. In an automatic longitudinally adjustable thrust transmitting device comprising slidably interfitted plunger and cylinder members, a body of fluid for transmitting thrust between the plunger member and one end of said cylinder member, at least one of said members having side walls defining a reservoir for fluidto be supplied to and returned from said body with change in length of said device, a stop member limiting movement of the plunger member away from said, body, saidrstop, member and-the other'of said first two namedmembers having facing surfaces in longitudinally spaced apart relation, each of said surfaces being formed at "least in part by a body of relativelytlow melting point material, and a tubular bellowshaving endpleatsiabutting said surfaces and longitudinally extending flanges embedded in said material.

3, Ahydraulic valve lifter of the self-contained-fluid type comprising generally cup-shaped cylinder and plunger members in slidably nesting relation and-forming a fluid pressure chamber between their respective end walls, an imperforate push rod seat abutting the open end of the plunger member, a push rod seat retainer having an elongated portion extending longitudinally of the cylinder member above said push rod seat and an imperforate flange connected to the open end of the cylinder member in a sealing relationship, an annular body of relatively low melting point metal bonded'to both said push rod seat and said flange, and a-tubula'r bellows looselysurrounding said elongated portion having end pleats abutting said annular bodies and terminating with oppositely directed longitudinally extending flanges embedded in said annular bodies.

4. A hydraulic valve lifter of the self-contained-fluid type comprising nesting generally cup-shaped cylinder and plunger members having slidably interfitted side wall portions spaced inwardly from their respective open ends and radially spaced other side wall portions adjacent their open ends, an imperforate push rod seat abutting the open end of the plunger member having an annular surface facing outwardly of the cylinder member, said surface having an annular recess therein; a push rod seat retainer including a tubular portion extending into the cylinder member and a flange portionsealingly connected to said other side Wall portion of the cylinder member, said tubular and flange portions forming an annular pocket at their juncture facing said recess, an annular body of low melting point material within said recess and bonded therein to said push rod,

type having a cylinder member open at one end, a hollow plunger reciprocable therein and having its corresponding end open and spaced inwardly of'the cylinder member from said cylinder member end, said plunger having its open end defining side Walls radially spaced from the open end defining side walls of the cylinder member, said plunger side walls being apertured to provide communication between the interior of the plunger and the open end of the cylinder member, and means sealing the cylinder member open end to the plunger open end and limiting movement of the plunger outwardly of the cylinder member, said means including a rigid tubular member extending into the open end of the cylinder member, a push rod seat socketably fitting the plunger open end and having an imperforate annular surface facing the extended end of said tubular member, said tubular member having an out-turned flange at its other end sealingly connected to the cylinder member open end, and a tubular bellows loosely embracing said tubular member and bonded at its respective opposite ends to said surface and said flange.

6. A hydraulic valve lifter of the self-contained-fiuid type having a cylinder member open at one end, a hollow plunger reciprocable therein and having its corresponding end open and spaced inwardly of the cylinder member from said cylinder member end, said plunger having its open end defining side walls radially spaced from the open end defining side walls of the cylinder member, said plunger side walls being apertured to provide communication between the interior of the plunger and the open end of the cylinder member, and means sealing the cylinder member open end to the plunger open end and limiting movement ofthe plunger outwardly of the cylinder member, said means including a rigid tubular member extending into the open end of the cylinder member, a push rod seat socketably fitting the plunger open end and having an imperforate annular surface facing the extended end of said tubular member, said annular surface being relieved adjacent one marginal extremity thereof by an annular recess, said tubular member having an outturned flange at its other end sealingly secured to the cylinder member open end, an annular body of solder substantially filling said recess and bonded therein to said push rod, an annular body of solder bonded to said flange and defining a surface facing said annular surface, and a tubular bellows having end pleats abutting said surfaces 7 and terminating with longitudinally extending flanges embedded in said bodies of solder.

7. In a hydraulic valve lifter having nestably associated cup-shaped plunger and cylinder members defining a chamber for a thrust transmitting body of fluid between their respective end walls and a reservoir above the plug er end wall for fluid entering and leaving said chamber, said plunger and cylinder members having their side walls adjacent their open ends radially spaced from each other, a push rod seat member abutting the plunger open end and having an imperforate push rod seating surface and a surrounding imperforate flat annular surface both facing outwardly of the cylinder member, a sheet metal retainer member including a tube extending longitudinally of the cylinder member having one end abuttable with said annular surface adjacent said seating surface and its other end provided with an external flange overlying the space between said plunger and cylinder side walls, said flange being sealingly secured to the cylinder member open end, and a tubular bellows sealingly interconnecting said annular surface and said flange externally of said tube, one of said plunger and retainer members having a passageway for flow of fluid between said space and the interior of the plunger member.

8. In a hydraulic valve lifter including a cylinder open at one end, a plunger reciprocable in the cylinder, and means for sealingly closing the open end of the cylinder including a tubular member disposed between the plunger and the open end of the cylinder and longitudinally extensible in response to plunger reciprocation-relative to the cylinder, and a rigid member fixed to the cylinder member outwardly thereof from said tubular member and having a tubular portion extending inwardly of and shielding the internal periphery of said tubular member, said tubular portion being open at both ends to accommodate passage therethrough of external means in thrust transmitting relation with the plunger.

9. The invention defined in claim 8, wherein the plunger adjacent end of said tubular portion is operatively abuttable with the plunger to limit plunger movement outwardly of the cylinder.

References Cited in the file of this patent UNITED STATES PATENTS 2,096,257 Moorhouse Oct. 19, 1937 2,109,809 Van Ranst Mar. 1, 1938 2,153,097 Moorhouse Apr. 4, 1939 2,278,963 Arola Apr. 7, 1942 2,553,756 Engemann May 22, 1951 2,689,555 Van Slooten Sept. 21, 1954 2,746,437 Van Slooten .4. May 22, 1956 FOREIGN PATENTS 121,417 Australia May 16, 1946