US3439660A

US3439660A - Tappet metering disk

Info

Publication number: US3439660A
Application number: US639849A
Authority: US
Inventors: Kenneth W Lesher
Original assignee: Standard Screw Co
Current assignee: Stanadyne LLC
Priority date: 1967-05-19
Filing date: 1967-05-19
Publication date: 1969-04-22
Anticipated expiration: 1986-04-22

Description

p i 69 K. w. LESHER 3,439,660

TAPPET METERING DISK Filed May 19, 1967 Sheet or'sfi/lf/g Zak); W 1 4% fa/far ///amgm April 1969 K w. LIESHEQR 3,439,660

TAPPET METERING DISK .Z-iled ma 19, 1967 Sheet .8 of s April 1959 K. w. LESHER 3,439,660

TAPPET METERING DISK Filed May 19, 1967 iiim0 i Z/k/ K221 United States Patent US. "Cl. 123-90 6 Claims ABSTRACT OF THE DISCLOSURE The device disclosed comprises a hollow hydraulic tappet, to the interior of which lubricant is conducted from the engine in which the tappet is positioned. Lubricant fluid is discharged from the hydraulic tappet toward the valve operating means and furnishes lubrication to the valve operating means including the rocker arm and associated parts. The tappet disclosed is associated with a hollow pushrod which leads to the rocker arm which moves an engine valve. Means are provided in the tappet to meter the flow of lubricant to the pushrod. This means comprises a generally flat disk provided on each face with a ring-like raised portion which is shaped with a gap or open space in the ring. The ends of the ring are separated. They overlap each other in one form. The rings are of non-uniform radial disposition with respect to the disk. A flat seat for the disk is provided within the tappet about the opening through which lubricant flows to the pushrod. When the disk is seated on the seat, lubricant can flow outwardly only through the gap between the ends of the ring and it is metered by the size of the gap between the ends of the ring.

This invention relates to improvements in a hydraulic tappet and particularly to hydraulic tappets characterized by metering means for metering lubricant fluid as it moves from the tappet to a point where lubrication is required.

The invention has for one object to provide a metering assembly in a hydraulic tappet which provides means for controlling the lubricant which can flow from the interior of the tappet to a pushrod of a lubricating system.

A still further object is to provide a metering disk upon which seating portions are formed and arranged so that wear between the seating portions and the seat upon which they sit is widely distributed and is not concentrated in a pattern identical with the pattern or plan of the seating portions of the tappet.

A further object is to provide a metering disk with the properties above mentioned and provided with seating portions on each side so that it is immaterial which side of the disk faces the seating portion within the tappet on which the disk is seated.

Other objects will appear from time to time in the following specification and claims.

The invention is illustrated diagrammatically in the accompanying drawings wherein:

FIGURE 1 is a sectional view through a conventional engine and valve operating gear showing a hydraulic tappet in position in the valve operating means,

FIGURE 2 is a vertical section on an enlarged scale showing the tappet of this invention,

FIGURE 3 is a plan view of one form of the disk,

FIGURE 4 is a transverse section taken at line 44 of FIGURE 3,

FIGURE 5 is a plan view of a modified form of disk embodying the invention,

FIGURE 6 is a transverse section taken at line 6-6 of FIGURE 5,

FIGURE 7 is a plan view of a further modification of the disk,

FIGURE 8 is a transverse section taken at line 8-8 of FIGURE 7,

FIGURE 9 is a plan view of a further modification in which the seating portion is in the form of an ellipse, and

FIGURE 10 is a transverse section taken at line 10 10 of FIGURE 9.

Like numerals will be used to describe like parts in the following description of the drawings.

The invention is illustrated in FIGURE 1 in a conventional internal combustion engine comprising a cylinder 1, a cylinder head 2, a valve 3, a valve spring 4, and a rocker arm 5, supported at 6 upon a stud 7. The rocker arm is adapted to be moved by a hollow pushrod 8 which is seated in a cup 9, having an orifice 10 formed in it. The cup is positioned in the hollow plunger 11 of a hydraulic tappet. It is mounted for reciprocation within a tappet cylinder or barrel which is provided with a closed bottom 13. The barrel 12 is perforated at 14 to permit engine lubricant to enter the tappet. The barrel is also perforated at 15 and is enlarged at 16 and shouldered at 17. The plunger may be reduced in external diameter at its inner end at 18 and may be provided intermediate its ends with a groove or channel 19 from which a perforation or passage 20 leads to the hollow interior 21 of the plunger.

At its inner end, the tappet plunger is provided with an opening 22 which may be closed by a valve 23 held in suitable relationship to the inner end of the plunger by a valve cage 24 which has openings 25 in its sides. It is also open at its bottom 26.

A spring 27, positioned within the barrel 12 and beneath the plunger 11, bears against a flange 28 of the valve cage 24 and is biased to move the plunger to the outermost position away from the closed bottom 13. Although the valve cage 24 is positioned upon the reduced extension 29' of the plunger 11 with a press fit, should any looseness occur, it will be held in position by the contact of the spring 27 with the flange 28.

A locking ring 30 is positioned in a suitable groove adjacent the open end 31 of the tappet barrel 12 and prevents accidental displacement of the plunger from the barrel.

A spring 32 may be positioned between the disk 23 and an adjacent portion of the valve cage 24. If present, it will be biased to move the valve 23 to the seating position of FIGURE 2.

The inner face of the cuplike member is provided with a flat seat 33, against which the seating portion of the disk 34 is adapted to seat to produce the metering etfect.

Any of the forms of disks shown in the drawings herewith may be used to effect metering. Each is held at a position adjacent the seat 33 by the shoulder 35 formed in the plunger 11. Several disks will be described in detail in connection with FIGURES 3 to 10 inclusive.

All reference numerals have not been applied to FIG- URE 1 because of the relatively small scale of the figure. The reference numerals are applied to FIGURES 2 to 10 inclusive and are used in the detailed discussion of these figures.

All of the forms of disks shown have a common important feature, namely that each disk is provided with two seating portions adapted to be seated against the seat 33. The two seating portions of each disk are positioned one on each face of the disk. This is clear, for example, from FIGURE 4 and other sectional views of disks. It is obvious that only one seating portion of a disk can be seated against the seat 33. The reason for two seating portions is that in assembly, if there were but one seating portion or ringlike member, the disk might be improperly assembled so that its single ringlike seating portion would be faced away from the seat 33. Should that occur, the disk when seated would not carry out a metering effect but would simply close the passage 10. By providing a seating portion or ringlike member on each face of the disk, it is certain that one of such seating portions will always be in opposition to the seat 33 and when the disk is moved to the seating portion, the ringlike portion will seat upon the seat 33 and the metering opening will be available to carry out the metering function. Only one of the ringlike seating portions can seat at a time. The other is merely to make sure that a metering part will always be in contact with the seat 33 when the disk has been moved to contact that seat.

The contact of the disk with the seat 33 is limited to the ringlike or C-like member on whichever side of the disk is facing the seat 33. In all forms of the disks, there is thus on each face of the disk a more or less C-like member whose ends do not meet. There is thus provided between the ends of each C-like member a gap which is effective as the metering gap.

A problem which is encountered in the use of the metering valve shown is that the metering valve will inevitably shift and rotate so that in effect its rotary movement, in whatever direction it takes place, will gradually wear the seat 33. When this occurs, there is always the possibility that the raised C portion will penetrate into a worn portion on the seat 33 and will thus reduce the clearance through the metering opening. It is one of the objects of the various structures shown to distribute the wear to as wide an area as possible over the surface of the flat seat 33. To accomplish this purpose, the raised seating portions or C-like members may be positioned not concentric with the disk or they may themselves be noncircular in plan so as to be of nonuniform radius from the center of the disk. In either arrangement, a wider surface is presented to the flat seat 33 when the disk is in the metering position and therefore in contact with the seat. Thus the wear of the disk on the seat is more widely distributed than otherwise would be the case.

The disk is generally identified by the numeral 34. The modifications, since they are embodied in the C-like or ringlike seating portions are indicated by different numerals.

In the forms of FIGURES 3 and 4, the seating portions comprise C-

like members

36 and 37 positioned, as shown particularly in FIGURE 4, on opposing faces of the disk. These two

portions

36 and 37 are provided respectively with flattened seating faces 38 and 39. Each has a gap or metering opening. The C-ring 36 has a metering opening 40 and the C-ring 37 has a metering opening 41.

The C-ring of FIGURES 3 and 4, although concentric with each other, are not concentric with the disk 34. An inspection of FIGURE 3 makes it clear that the outer C-ring 37 is closer to the periphery of the disk 34 at the lower side of FIGURE 3 than at its upper side of the figure. This arrangement of the C-rings results in spreading the Wear on the seat 33 over a wider area than is the case when the C-rings are concentric with the disk in which they are formed.

The precise contour of the

Crings

36 and 37 of FIG-

URES

3 and 4 is not a limiting factor of the invention because the arrangement of C-rings so that they will not be concentric with the disk in which they are formed can be carried out no matter what the precise shape or contour of the C-rings may be.

As shown in FIGURES and 6, a modified construction appears in which the C-rings are circular and concentric with each other and with the disk in which they are formed and the raised portions are therefore of uniform radial disposition with respect to the disk. Thus the disk 42 has a C-ring 43 in one surface and a C-ring 44 in the other surface. The C-ring 43 defines a metering opening 45 and the C-ring 44 defines a metering opening 46. The difference between the contours or shapes of the C-

rings

43 and 44 and those of FIGURES 3 and 4 is merely illustrative of the fact that the rings may take many different forms without departing from the spirit of the invention and while it is preferable that the rings be not concentric with the disk, it is recognized that that arrangement is possible. The invention is, therefore, not limited to any particular shape of C-ring or equivalent member.

In the form of FIGURE 7, the contour of the C-rings is substantially the same as that of FIGURES 5 and 6, although they are not identical. In the form of FIGURES 7 and 8, the disk 47 carries on one face a C-ring 48 and on the opposite face, a C-ring 49.

Metering openings

50 and 51 are formed respectively in the C-rings 48 and 49'. From an inspection of FIGURE 7 in particular, it is obvious that the C-rings in that form of the invention are not concentric with the disk 47. Hence, the arrangement of the C-rings in the form shown in FIGURES 7 and 8 is essentially the same as that shown in 3 and 4 in which the rings are not concentric with the disk in which they are formed.

In the form of FIGURES 9 and 10, the disk is provided with C-rings which are not circular in plan. As shown, they are elliptical. The invention is not limited to any particular type of curved shape or arrangement of C-rings. In fact it is not limited to curved seating members at all. However, as shown in FIGURES 9 and 10, the disk 52 has formed on one surface a C-ring 53 which provides a metering opening 54- and on its opposite surface the disk 52 has formed a C-ring 55 which provides between its ends a metering opening or gap 56.

As is the case with all of the forms of metering disks shown, a ring or ringlike member is formed on each face of the disk and only one at a time can be seated against the seat 33. The form of FIGURES 9 and 10 may have the

rings

53 and 55 formed concentric with each other or they may not be concentric. They may be concentric with the disk 52 or they may not be.

One of the advantages of the form shown in FIGURES 9 and 10 is that since the C-rings are elliptical rather than truly circular, whatever wear will occur on the seat due to rotation of the disk is spread over a relatively wider area than would be the case if the rings were circular and were also concentric with the circular disk. Therefore, the form of FIGURES 9 and 10 accomplish the purpose of spreading wear on the seat 33' in the same manner as do the forms of FIGURES 3 and 7.

I claim:

1. In combination in a hydraulic valve lifter,

a barrel and a plunger mounted therein for reciprocation,

a pushrod receiving member in said plunger,

a lubricant passage through the wall of said barrel and through the wall of said plunger and through said pushrod receiving member, and

means for controlling the flow of fluid through said last mentioned passage,

said means comprising a valve seat about said passage and a relatively fiat valve disk movably mounted adjacent said valve seat and provided on each surface with a raised seating portion and a metering passage formed through each of said seating portions,

said raised seating portions being of nonuniform radial disposition with respect to the center of said disk.

2. The combination of claim 1 further characterized by the fact that the raised seating portions of the valve disk are noncircular.

3. The combination of claim -1 further characterized by the fact that the raised seating portions are nonconcentric with said disk.

4. In combination in a hydraulic valve lifter,

a barrel and a plunger mounted therein for reciprocation,

a pushrod receiving member in said plunger,

3,439,660 5 6 means for controlling the flow of fluid through said fact that the raised portions are out of center with respect last mentioned a age, to the plan of the valve disk. said means comprising a valve seat about said passage The CQmbiPatiOII of claim 4 chafacterized y f d a relatively fi t valve disk movably mounted fact that the raised portions are nonclrcular and posiadjacent Said valve seat and provided on each Sup 5 tloned upon the valve disk concentrically wlth respect to face with a raised seating portion and a metering the plan of the disk S plassagedformted throuigolileach 0; said selzraltingspgltioins, References Cited at raise sea lng por s corn r1s1ng can 0 1S- tributing the wear of the raised portion upon the UNITED STATES PATENTS valve seat over an area greater than that of the con- 10 1,899,251 2/ 1933 Zerk 13842 X tacting area of the raised portion, said means com- 2,840,063 6/ 1958 Pllr as. prising the arrangement of the raised portion upon 3,273,547 9/ 1966 Leshen the valve disk such that the radius of the raised portion with respect to the center of the disk is non- 15 AL LAWRENCE SMITH 'i Exammer' uniform. US. Cl. X.R.

5. The combination of claim 4 characterized by the