Roller follower hydraulic tappet

• US 4,607,599 A
• Filed: 05/15/1985
• Issued: 08/26/1986
• Est. Priority Date: 05/15/1985
• Status: Expired due to Term

• Current Assignee: Eaton Corp. (Wisconsin) (Eaton Corporation PLC.)
• Original Assignee: Eaton Corp. (Wisconsin) (Eaton Corporation PLC.)
• Inventors: Clark, David P., Buente, Stephen M.
• Primary Examiner(s): Lazarus, Ira S.
• Application Number:
  US06/734,634
• Time in Patent Office: 468 Days
• Field of Search: 123/90.5, 123/90.55, 123/90.48
• US Class Current: 123/90.5
• CPC Class Codes: F01L 1/255 between cam and rocker arm
• CPC Class Codes: F01L 2305/00 Valve arrangements comprising rollers

Abstract

A hydraulic lash adjusting tappet for an internal combustion engine of the type supplying oil to a passage communicating with the tappet-receiving guide bore in the engine. The tappet has a roller follower on the cam end and a registration means adjacent the opposite end for orienting the roller with respect to the engine cam. The tappet body has at least one localized collector recess disposed longitudinally coincident and peripherally spaced with the registration means. In one embodiment the registration comprises a pair of oppositely disposed flats and the tappet has a pair of diametrically opposed collector recesses interconnected by a peripheral groove spaced longitudinally therefrom to by-pass the flats and provide sufficient surface for leakage control. An oil inlet hole is formed in one of the collector recesses for supplying the lash adjuster valve in the tappet. The localized recess is aligned with the engine supply passage by the orientation of the registration surface.

Claims

1. A hydraulic lash adjusting tappet for use in the valve gear of an internal combustion engine comprising:

(a) body means having the outer periphery thereof adapted for sliding movement in a bore provided in the engine, said bore of the type supplied by an oil passage communicating therewith;

(b) roller follower means rotatably received on one end of said body means, said roller follower means adapted for rolling contact with an engine camshaft;

(c) registration surface means adapted for moveable registration thereagainst comprising at least one especially configured surface formed on said body means remote from said follower means and adapted for registration thereagainst for orienting said body means in said bore for ensuring proper alignment of said roller means with the engine camshaft;

(d) plunger means, including hydraulic lash adjusting means, said plunger means moveably received in a cavity formed in said body means, said plunger formed to interfit said cavity so as to form a hydraulic pressure chamber and define precision leakdown surfaces therebetween;

(e) said body means defining a fluid inlet port disposed on the periphery thereof for communicating with said engine bore oil passage when said body means is oriented in said bore by said registration means, said body means further defining a pair of localized collector surface means diametrically opposite thereon, said collector surface means disposed axially coincident with and circumferentially spaced from said registration surface means to provide a circumferentially staggered and on the periphery of said body means for leakage control between said body means and said engine oil bore one of said surface means disposed to communicate with said fluid inlet port, said collector surface means further including passage means operable to maintain communication of said engine bore oil passage with said fluid inlet port during movement of said body means in said engine bore caused by contact of said roller means with said engine camshaft.

2. The device defined in claim 1, wherein registration means comprises a pair of flats disposed on oppoiste sides of said body means and said fluid inlet port and collector surface means are located peripherally in quadrature with said flats.

3. The lash adjuster defined in claim 1, wherein said pasage means comprises a collector groove extending around the periphery thereof and communicating with said localized collector surface means.

4. A hydraulic lash adjuster for use in the valve gear of an internal combustion engine comprising:

(a) body means having the outer periphery thereof adapted for sliding movement in a bore provided in the engine, said bore of the type supplied by an oil passage communicating therewith;

(b) roller follower means rotatably received on one end of said body means, said roller follower means adapted for rolling contact with an engine camshaft;

(c) said body means defining a cavity and having plunger means slidably received therein, to form a high pressure chamber said plunger means including one-way valve means supplying said chamber;

(d) orientation means comprising at least one registration surface formed on said body means and adapted for being contacted to align said roller follower means with the engine camshaft;

(e) fluid inlet means formed in said body means for communicating fluid from said engine oil passages to said one way valve means, said inlet means comprising,

(i) a localized collector recess formed on the periphery of said body at orientation with respect to said at least one at a generally common longitudinal station along said body means with said at least one registration surface and circumferentially spaced therefrom to provide a circumferentially staggered land on a periphery of said body means for leakage control between said body means and said engine oil bore,

(ii) a feed aperture formed through the wall of said body means and communicating with said cavity, said feed aperture disposed circumferentially in quadrature and at a common longitudinal station along said body means with said localized collector means,

(iii) connector groove means formed in the periphery of said body means and extending circumferentially thereabout for interconnecting said localized collector means and said feed aperture;

wherein said connector groove means provides a circumferential by-pass about said orientation means.

5. The hydraulic lash adjuster defined in claim 4, wherein said registration means comprises a pair of flats disposed oppositely on said body means in spaced parallel relationship.

6. The hydraulic lash adjuster defined in claim 4, wherein said registration means comprises a pair of flats disposed oppositely on said body means in spaced parallel relationship, and said localized collector means comprises a pair of oppositely disposed recesses located circumferentially intermediate said flats.

7. The hydraulic lash adjuster defined in claim 4, wherein said registration means comprises a pair of flats disposed oppositely on said body means in spaced parallel relationship and said collector groove means is longitudinally intermediate said flats and said roller follower means.

8. The hydraulic lash adjuster defined in claim 4, wherein said localized collector means comprises a pair of oppositely disposed recesses and said feed aperture is formed in one of said recesses.

9. The hydraulic lash adjuster defined in claim 4, wherein said localized collector means is disposed on said body means intermediate said orientation means and said connector groove.

10. A hydraulic lash adjusting tappet for use in the valve gear of an internal combustion engine of the type having a bore provided therein with an oil passage communicating therewith and a camshaft for periodic tappet movement, said tappet comprising:

(a) body means having the outer periphery thereof adapted for sliding movement in said bore;

(b) roller follower means rotatably received on one end of said body means, said roller follower means adapted for rolling contact with said engine camshaft;

(c) registration surface means adapted for moveable registration thereagainst comprising at least one especially configured surface formed on said body means remote from said follower means and adapted for registration thereaginst for orienting said body means in said bore for ensuring proper alignment of said roller means with the engine camshaft;

(d) plunger means, including hydraulic lash adjusting means, said plunger means moveably received in a cavity formed in said body means, said plunger formed interfit said cavity so as to form a hydraulic pressure chamber and define precision leakdown surfaces therebetween; and

,

(e) said body means further comprising at least one localized collector surface means disposed on the periphery of said body means and spaced circumferentially from said especially one configured surface and longitudinally at a common station therewith, said collector surface means having a fluid inlet passage located therein communicating with said hydraulic lash adjusting means, said collector surface configured to extend longitudinally an amount sufficient to maintain said fluid communication between said engine oil passage and said fluid inlet passage during sliding movement of said tappet in said engine bore, said collector surface means disposed to define a circumferentially staggered land on the periphery of said body means for leakage control between said body means and said engine oil bore for preventing pressure loss from oil flow from said engine passage to said especially one configured surface, wherein, upon receipt of said tappet in said engine bore and contact with said registration means, said localized collector surface means is oriented in said bore with said engine oil passage.