US3836293A

US3836293A - Rotary piston internal combustion engine of trochoidal construction

Info

Publication number: US3836293A
Application number: US00329194A
Authority: US
Inventors: H Lamm
Original assignee: Daimler Benz AG
Current assignee: Daimler Benz AG
Priority date: 1972-02-03
Filing date: 1973-02-02
Publication date: 1974-09-17
Anticipated expiration: 1991-09-17
Also published as: DE2205015A1; JPS4887210A; FR2170736A5

Abstract

A rotary piston internal combustion engine of trochoidal construction which consists essentially of lateral parts and at least of one housing casing, in case of multi-disk internal combustion engines, of one or several intermediate parts, provided with hollow spaces for the accommodation of the cooling medium in each housing part and with ribs arranged in the hollow spaces; the ribs and/or the inner walls of the housing parts, particularly of the housing casing are provided with turbulenceproducing projections, preferably within the area of the minor axis in the hot arc.

Description

1 States Patent 1' [451 Sept. 17, 11974 1 ROTARY PISTON INTERNAL COMBUSTION ENGINE OlF TROCIIOIDAL CONSTRUCTION [75] Inventor: Heinz lLaimm, Esslingen-St.

Bernhardt, Germany [73] Assignee: Daimler-Benz Aktiengesellschaft,

Stuttgart, Germany 22 Filed: Feb. 2, 1973 21 Appl. No.: 329,194

[30] Foreign Application Priority Data Feb. 3, 1972 Germany 2205015 [52] US. C1. 418/83, 123/801 [51] Int. Cl.... F0lc 21/06, F040 29/04, F02b 55/10 [58] Field of Search 418/60, 61 A, 83;

[56] References Cited UNITED STATES PATENTS Froede 418/83 3,313,276 4/1967 Ito ct n1. 418/83 3,561,894 2/1971 King 418/61 A 3,588,296 6/1971 Toyuma r t r 418/83 3,644,070 2/1972 Lcrmusiaux 418/83 Primary Examiner-John J. Vrablik Attorney, Agent, or FirmCraig & Antonelli [5 7] ABSTRACT A rotary piston internal combustion engine of trochoidal construction which consists essentially of lateral parts and at least of one housing casing, in case of multi-disk internal combustion engines, of one or several intermediate parts, provided with hollow spaces for the accommodation of the cooling medium in each housing part and with ribs arranged in the hollow spaces; the ribs and/or the inner walls of the housing parts, particularly of the housing casing are provided with turbulence-producing projections, preferably within the area of the minor axis in the hot arc.

28 C1aims,'4 Drawing Figures MENIEHSEPI mm SHEET 1 BF 2 HG. f

The present invention relates to a rotary piston internal combustion engine of trochoidal construction, consisting essentially of lateral housing parts and of at least one housing casing, inmulti-disk internal combustion engines of one or several intermediate parts, with hollow spaces for the accommodation of a cooling medium in each housing part and with ribs arranged in the hollow spaces.

In rotary piston internal combustion engines which are adapted to be loaded highly, temperatures occur ever so often at the casing running surfaces, especially in the spark plug proximity which exceed the permissive limits.

These temperatures may be due both to the combustion as also to an inadequate cooling.

During unfavorable operating conditions of the internal combustion engine, steam or vapor bubbles form at the hottest places along the rough skin of the casting of the housing parts, which have the effect of an insulating layer and negatively influence the cooling effect. Additionally, they also enhance the formation of deposits out of the cooling medium (for example, lime) locally at these places.

Furthermore, a trouble-free feed of the cooling medium is not assured by the tom-along and enclosed vapor bubbles in the cooling medium.

It is the aim of the present invention to undertake measures which prevent beforehand locally occurring overheating appearances in that the produced heat is rapidly and reliably conducted away from the casing running surface.

The underlying problems are solved according to the present invention in that the ribs and/or inner walls of the housing parts, especially of the housing casing are provided in the hot arc with turbulence-producing projections preferably within the area of the minor axis.

In an advantageous embodiment according to the present invention, the projections may be constructed nose-like.

Not only a turbulence preventing the vapor bubble formation is produced by the arrangement of the projections in the hollow spaces, which turbulence remains nearly preserved over a longer distance, but also a surface enlargement favorable for the heat removal is attained thereby.

Accordingly, it is an object of the present invention to provide a rotary piston internal combustion engine of trochoidal construction which avoids by simple means the aforementioned shortcomings and drawbacks encountered in the prior art.

Another object of the present invention resides in a rotary piston internal combustion engine of trochoidal construction which effectively prevents temperatures at the casing running surface that exceed the permissive limits.

A further object of the present invention resides in a rotary piston internal combustion engine which is characterized by an improved cooling efficiency.

Still a further object of the present invention resides in a rotary piston internal combustion engine of trochoidal construction which effectively eliminates the formation of vapor bubbles thereby improving the cooling effectiveness.

Another object of the present invention resides in a cooling system for a rotary piston internal combustion engine, especially of trochoidal construction, which far-reachingly precludes the formation of deposits out of the cooling medium.

These and further objects, features and advantages of the present invention will become more apparent from the following description when taken in connection with the accompanying drawing which shows, for purposes of illustration only, one embodiment in accordance with the present invention, and wherein:

FIG. 1 is a partial cross-sectional view through a housing casing in proximity of the minor axis of an engme;

FIG. 2 is a cross-sectional view, on an enlarged scale, through the inner wall of the housing casing facing the running surface.

FIG. 3 is a partial cross-sectional view of a rotary piston internal combustion engine taken along the line Ill- -III of FIG. 1; and

FIG. 4 is a partial cross-sectional view of a multi-disk rotary piston internal combustion engine according to the present invention.

Referring now to the drawing wherein like reference numerals are used throughout the various views to designate like parts, and more particularly to FIG. I, a housing casing generally designated by reference numeral I of a rotary piston internal combustion engine is, according to this figure, provided with a hollow space 2 for the accommodation of a cooling medium. Ribs 3 and 4 are arranged in the hollow space 2 which extend both at a predetermined angle (ribs 3) as also parallel to the flow direction of the cooling medium (ribs 4).

Within the area of the hot arc of the internal combustion engine, i.e., -as viewed in the direction of rotation of the piston P-from a point upstream or in front of the minor axis a (FIG. 3) in the hot arc up to shortly in front or upstream of the minor axis in the cold arc between the exhaust channel 13 and inlet channel 114 FIG. 3, nose-like projections are arranged at the ribs 3 and 4 as well as at a spark plug boss 5 disposed ahead of the minor axis a and at each inner wall 6 of the housing casing ll, which projections produce a turbulence advantageous for the cooling medium and effective over the entire width of the housing casing.

The projections which are designated by reference numeral 7 are disposed over the entire circumference of the spark plug boss 5. Two projections 8 each are arranged at the ribs 3 and 41- at each longitudinal side thereof.

Especially the inner wall 6 facing the casing running surface 10 is provided according to FIG. 2 with a large number of projections 9 whereas the projections 12 arranged at the lateral walls llll of the housing casing I have a larger spacing from one another.

FIG. 4 illustrates a multi-disk construction wherein a pair of housing casings l are provided with an intermediate housing part 15 disposed between the casings. Each of the casings are provided with a hollow space 2 for the accommodation of a cooling medium and include ribs, only one of which is shown in FIG. 5, and nose-

like projections

8, 9, 12 arranged at the ribs, running surface and lateral walls, respectively, of the casings ll.

Possibly also the adjacent lateral or intermediate parts may be provided within the adjoining area of the trochoidal contour of the casing running surface-within the area near the spark plug bosswith projections serving for creating a turbulence of the cooling medium.

The danger of the vapor bubble formation and therewith an impairment of the cooling medium supply is thereby completely eliminated.

While I have shown and described two embodiments in accordance with the present invention, it is understood that the same is not limited thereto but is susceptible of numerous changes and modifications as known to those skilled in the art, and I therefore do not wish to be limited to the details shown and described herein but intend to cover all such changes and modifications as are encompassed by the scope of the appended claims.

What I claim is:

1. An arrangement for a rotary piston internal combustion engine including at least one housing casing and lateral housing parts, the housing casing being provided with hollow spaces for the accommodation of a cooling medium the arrangement comprising: at least one first rib means disposed in the hollow space arranged parallel to the flow direction of the cooling medium, at least one second rib means disposed in the hollow space arranged at a predetermined angle to the flow direction of the cooling medium, and projection means provided on at least one of said first and second rib means for producing turbulence of the cooling medium.

2. A rotary piston internal combustion engine arrangement according to claim 1, wherein the housing casing includes inner walls, and wherein at least one of said inner walls is provided with projection means.

3. A rotary piston internal combustion engine arrangement according to claim 1, including a spark plug boss means projecting into a respective hollow space and wherein projection means are provided about the entire circumference of said spark plug boss means 4. A rotary piston internal combustion engine arrangement according to claim 1, wherein said housing casing includes a running surface and inner wall, and wherein at least one of said inner walls adjoins said running surface, projection means being disposed on said last-mentioned inner wall and extending in a direction facing away from said running surface.

5. A rotary piston internal combustion engine arrangement according to claim 1, wherein said projection means are of noselike construction.

6. A rotary piston internal combustion engine arrangement according to claim 5, wherein said turbulence-producing projection means are arranged at least within the area of the minor axis in thehot arc of the engine.

7. A rotary piston internal combustion engine arrangement according to claim 1, wherein said first and second rib means are of elongated configuration, said projection means being provided along the longitudinal sides thereof.

8. A rotary piston internal combustion engine arrangement according to claim 7, wherein said first rib means extends in the longitudinal direction of a respective hollow space.

9. A rotary piston internal combustion engine arrangement according to claim 8, wherein said first rib means are disposed substantially centrally in the hollow space said second rib means being disposed laterally of the center longitudinal plane of the hollow space.

10. A rotary piston internal combustion engine arrangement according to claim 1, wherein said projection means includes a plurality of spaced noselike projections provided on both of said first and second rib means.

11. A rotary piston internal combustion engine arrangement according to claim 10, wherein said housing casing includes a pair of spaced lateral inner walls, and wherein spaced projection means are disposed on at least one of said lateral inner walls.

12. A rotary piston internal combustion engine arrangement according to claim 1, wherein said housing casing includes a pair of spaced lateral inner walls, and wherein projection means are disposed on at least one of said lateral inner walls.

13. A rotary piston internal combustion engine arrangement according to claim 12, wherein projection means are disposed on both of said lateral inner walls.

14. A rotary piston internal combustion engine arrangement according to claim 13, wherein said housing casing includes a running surface and an inner wall adjoining said running surface, and wherein projection means are disposed on said last-mentioned inner wall.

15. A rotary piston internal combustion engine arrangement according to claim 13, wherein projection means are disposed on both of said lateral inner walls.

16. A rotary piston internal combustion engine arrangement according to claim 15, wherein said housing casing includes a running surface and an inner wall adjoining said running surface, and wherein projection means are disposed on said last-mentioned inner wall.

17. A rotary piston internal combustion engine arrangement according to claim 1, wherein said turbulence-producing projection means are arranged at least within the area of the minor axis in the hot arc of the engine.

18. A rotary piston internal combustion engine arrangement according to claim 17, wherein the engine is of trochoidal construction.

19. A rotary piston internal combustion engine arrangement according to claim 17, wherein the internal combustion engine is of multi-disk construction, and wherein at least one intermediate housing part is disposed between two adjoining housing casing, each of said housing casings including a hollow space for the accommodation of a cooling medium.

20. A rotary piston internal combustion engine according to claim 17, wherein the housing casing in cludes inner walls, and wherein at least one of said inner walls is provided with turbulence-producing projection means.

21. A rotary piston internal combustion engine arrangement according to claim 20, wherein said projection means are of nose-like construction.

22. A rotary piston internal combustion engine arrangement according to claim 21, including a spark plug boss means projecting into a respective hollow space, and wherein projection means are provided about the entire circumference of said spark plug boss means.

23. A rotary piston internal combustion engine arrangement according to claim 22, wherein said first and second rib means are of elongated configuration, said projection means being provided along the longitudinal sides thereof.

24. A rotary piston internal combustion engine arrangement according to claim 23, wherein said first rib means extends in the longitudinal direction of a respective hollow space.

25. A rotary piston internal combustion engine arrangement according to claim 24, wherein said first rib means are disposed substantially centrally in the hollow space, said second rib means being disposed laterally of the center longitudinal plane of the hollow space.

26. A rotary piston internal combustion engine arrangement according to claim 25, wherein said housing casing includes a running surface, and wherein said at least one of said inner walls of said housing casing adjoins said running surface, projection means being disposed on said last mentioned inner wall and extending in a direction away from said running surface.

27. A rotary piston internal combustion engine arrangement according to claim 26, wherein said housing casing includes a pair of spaced lateral inner walls, and wherein projection means are disposed on at least one of said lateral inner walls.

28. A rotary piston internal combustion engine arrangement according to claim 27, wherein projection means are disposed on both of said lateral inner walls. l

Claims

3. A rotary piston internal combustion engine arrangement according to claim 1, including a spark plug boss means projecting into a respective hollow space and wherein projection means are provided about the entire circumference of said spark plug boss means

4. A rotary piston internal combustion engine arrangement according to claim 1, wherein said housing casing includes a running surface and inner wall, and wherein at least one of said inner walls adjoins said running surface, projection means being disposed on said last-mentioned inner wall and extending in a direction facing away from said running surface.

6. A rotary piston internal combustion engine arrangement according to claim 5, wherein said turbulence-producing projection means are arranged at least within the area of the minor axis in the hot arc of the engine.

20. A rotary piston internal combustion engine according to claim 17, wherein the housing casing includes inner walls, and wherein at least one of said inner walls is provided with turbulence-producing projection means.

28. A rotary piston internal combustion engine arrangement according to claim 27, wherein projection means are disposed on both of said lateral inner walls.