Piston and connecting rod assembly

• US 5,115,725 A
• Filed: 03/27/1991
• Issued: 05/26/1992
• Est. Priority Date: 03/30/1990
• Status: Expired due to Term

• Current Assignee: Isuzu Motors Limited
• Original Assignee: Isuzu Motors Limited
• Inventors: Horiuchi, Shigeaki
• Primary Examiner(s): Look, Edward K.
• Assistant Examiner(s): LOPEZ, FRANK D
• Application Number:
  US07/675,771
• Time in Patent Office: 426 Days
• Field of Search: 92/187, 92/158, 92/159, 403/124, 403/125, 403/127, 74/579 E
• US Class Current: 92/157
• CPC Class Codes: F02B 23/0672 Omega-piston bowl, i.e. the combustion space having a central projection pointing towards the cylinder head and the surrounding wall being inclined towards the cylinder center axis the surrounding wall being exactly vertical F02B23/0696
• CPC Class Codes: F02B 3/06 with compression ignition compression ignition engines using air or gas for blowing fuel into compressed air in cylinder F02B13/02
• CPC Class Codes: F02F 2200/04 Forging of engine parts
• CPC Class Codes: F02F 3/00 Pistons
• CPC Class Codes: F16J 1/14 with connecting-rods, i.e. pivotal connections
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y10T 403/32655 Interposed concavo-convex component

Abstract

An arrangement wherein a concave portion on a support end of a connecting rod is slidably engaged with a convex portion formed in a lower part of a piston, and a retainer ring member supported on a skirt portion of the piston is placed in contact with the lower part of the concave rod end.

Claims

1. Internal combustion engine apparatus comprising:

a piston means having one end defining a crown surface and another end defining an annular piston engagement surface;

connecting rod means having an elongated middle portion, one end adapted for connection to a crank shaft and an opposite end defining an annular rod engagement surface slidably engaged with said piston engagement surface along an annular junction;

said rod engagement surface and said piston engagement surface being shaped and arranged to provide for said connecting rod means a center of oscillation substantially displaced from said engaged surfaces in a direction toward said crown surface;

a chamber formed between said piston means and said opposite end of said rod means;

said chamber disposed within said annular junction, intersecting said annular junction, and extending transversely to the axis of said elongated middle portion of said rod means so as to substantially reduce the width of said annular junction;

passage means providing an oil flow path to said chamber; and

retainer means coupled between said piston means and said connecting rod means and adapted to maintain said piston engagement surface engaged with said rod engagement surface.

2. An apparatus according to claim 1 wherein said opposite end further defines a convex support surface, and said retainer means defines a concave retainer surface engaged with said support surface.

3. An apparatus according to claim 2 wherein said piston means comprises a central body portion defining said piston engagement surface, and a skirt portion projecting from said crown surface and spaced from said body portion so as to form therewith an annular cavity intersecting said annular junction.

4. An apparatus according to claim 3 wherein an outer surface of said skirt portion defines an annular recess, said skirt portion defines a plurality of orifices communicating with said recess, and said retainer means defines a plurality of openings communicating with said orifices.

5. An apparatus according to claim 3 wherein said retainer means comprises annular means surrounding said rod means and fixed to said skirt portion.

6. An apparatus according to claim 5 wherein said passage means further provides an oil flow path to said annular cavity.

7. An apparatus according to claim 6 wherein said middle portion and said opposite end are detachably secured.

8. An apparatus according to claim 5 wherein said retainer means comprises a ring defining said retainer surface and a threaded nut engaging said skirt portion and maintaining engagement between said retainer surface and said support surface.

9. An apparatus according to claim 2 wherein said piston means comprises a piston member defining at opposing ends said crown surface and a base surface, and a slide member defining said piston engagement surface and a slide surface slidably engaged with said base surface;

and said slide member is adapted to accommodate relative transverse motion between said connecting rod means and said piston member.

10. An apparatus according to claim 9 wherein said slide member and said opposite end define said chamber.

11. An apparatus according to claim 10 wherein said base surface and said slide surface are substantially planar, said rod engagement surface is concave and said piston engagement surface is convex.

12. An apparatus according to claim 11 wherein all of said concave and convex surfaces are spherical.

13. An apparatus according to claim 10 wherein said base surface and said rod engagement surface are concave, and said piston engagement surface and said slide surface are convex.

14. An apparatus according to claim 13 wherein all of said concave and convex surfaces are spherical.

15. An apparatus according to claim 10 wherein said piston engagement surface and said base surface are convex, and said rod engagement surface and said slide surface are concave.

16. An apparatus according to claim 15 wherein all of said concave and convex surfaces are spherical.

17. An apparatus according to claim 10 wherein said piston engagement surface and said rod engagement surface are shaped to produce annular, substantially linear engagement therebetween.

18. An apparatus according to claim 17 wherein said piston engagement surface and said rod engagement surface are spherical with different centers.

19. An apparatus according to claim 17 wherein one of said piston engagement surface and said rod engagement surface is spherical and the other is conical.

20. An apparatus according to claim 10 wherein said body portion and said slide member define an auxiliary chamber, and said passage means further provides an oil flow path to said auxiliary chamber.

21. An apparatus according to claim 9 wherein said piston means comprises a central body portion defining said piston engagement surface, and a skirt portion projecting from said crown surface and spaced from said body portion so as to form therewith an annular cavity intersecting said annular junction.

22. An apparatus according to claim 21 wherein said retainer means comprises annular means surrounding said rod means and fixed to said skirt portion.

23. An apparatus according to claim 21 including an annular insert retained between said body portion and said skirt portion, said insert dividing said annular cavity into two annular portions and defining oil inlet and oil outlet openings.

24. An apparatus according to claim 9 including ball bearing means disposed between at least one of said support and retainer surfaces and said rod and piston engagement surfaces.