US3921593A - Cooling system for the cooling of the housing of a rotary piston internal combustion engine - Google Patents

Cooling system for the cooling of the housing of a rotary piston internal combustion engine Download PDF

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Publication number
US3921593A
US3921593A US295481A US29548172A US3921593A US 3921593 A US3921593 A US 3921593A US 295481 A US295481 A US 295481A US 29548172 A US29548172 A US 29548172A US 3921593 A US3921593 A US 3921593A
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United States
Prior art keywords
cooling
space
piston
running surface
end part
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Expired - Lifetime
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US295481A
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English (en)
Inventor
Heinz Lamm
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Daimler Benz AG
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Daimler Benz AG
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Publication of USB295481I5 publication Critical patent/USB295481I5/en
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B55/00—Internal-combustion aspects of rotary pistons; Outer members for co-operation with rotary pistons
    • F02B55/08—Outer members for co-operation with rotary pistons; Casings
    • F02B55/10—Cooling thereof
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B53/00—Internal-combustion aspects of rotary-piston or oscillating-piston engines
    • F02B2053/005—Wankel engines

Definitions

  • a cooling system with a liquid cooling medium for cooling the housing of a rotary piston internal combustion engine especially of trochoidal construction, which consists of at least one casing, of end parts and possibly of one or several intermediate parts, in which the cooling system consists of at least two cooling circulations which are completely separated from one another; the cooling media of the two cooling circulations may thereby have different temperatures.
  • FIGI COOLING SYSTEM FOR THE COOLING OF THE HOUSING OF A ROTARY PISTON INTERNAL COMBUSTION ENGINE as well as of the intermediate and end parts changes only slightly and that the gas-tightness between the individual housing parts is considerably improved. This gas-tightness cannot be assured in the prior art cooling
  • the present invention relates to a cooling system 5 systems since none of the customary elastic seals can be with a liquid cooling medium for purposes of cooling a housing consisting at least of a casing, of end parts and possibly of one or several intermediate parts of a rotary piston internal combustion engine, especially of trochoidal type of construction.
  • Such types of prior art cooling systems consist of one cooling circulation which especially in rotary piston internal combustion engines with several disks, represents a widely extended and branched system. Since in a rotary piston internal combustion engine, in contrast, for example, to a reciprocating piston internal combustion engine, the heat yield, i.e., the amount of heat produced is very different in the individual areas, the cooling system has to be matched very carefully. Thus, throttling places for the cooling medium are installed in order to supply the individual areas with different quantities of cooling medium. This entails the disadvantage that the cooling medium pump has to be dimensioned very large and that it possesses a very high input power. Notwithstanding a careful matching, however, local overheatings cannot be avoided by reason of an unfavorable distribution of the cooling medium or by reason of inadequate venting.
  • the present invention is concerned with the task to avoid the aforementioned shortcomings.
  • the underlying problems are solved according to the present invention in that the cooling system consists of at least two completely separate cooling circulatory systems.
  • the cooling medium quantities in each cooling medium circulation are considerably smaller than if only one single cooling circulation were present. Throttling places are not necessary in the cooling system, and the matching of 'the cooling system is considerably facilitated. Also, the small cooling medium quantity in each cooling circulatory system brings about a very rapid heat-up of the cooling medium after a cold start.
  • the cooling system is further improved according to an advantageous embodiment of the present invention in that the cooling media of the difi'erent cooling circulatory systems have differently high temperatures.
  • the cooling media may thereby consist of different substances depending on the temperature.
  • the cooling system is further improved according to the present invention in that the cooling media of the different cooling circulatory systems cool different areas of the housing having differing heat yield or heat production. These differing heat quantities can be conducted away either by differing cooling medium quantities or with the aid of different cooling medium temperatures if a cooling circulatory system with lower cooling medium temperature is consequently coordinated to an area of the housing with higher heat yield.
  • the temperature of the hottest cooling medium is selected sufficiently high, heat can be given off from the cooling medium to the housing in individual, particularly cool areas of the housing.
  • the housing assumes everywhere an approximately equal temperature which also signifies a uniform housing expansion.
  • the cooling medium of one cooling circulatory system enters the housing at the place of the area to be cooled where the largest heat quantity of this area is produced or in proximity 15 thereof, and leaves at the place with lowest heat yield or in proximity thereof.
  • the temperature of the housing can thus be kept approximately the same also at the individual places of an area since the entering relatively cool cooling water absorbs a larger amount of heat then the already heated discharged cooling water.
  • the cooling system of this invention may consist of two cooling circulations with differing temperatures, of which the cooler cooling circulation flows through the area of the casing opposite the inlet and outlet channel whereas the hotter cooling medium flows through the adjacent area of the casing adjoining in the direction of the piston up to the area of the inlet channel or therebeyond up to the area in which the combustion gases are present during the beginning of the suction cycle.
  • the cooler cooling medium thus cools the area with the greatest heat yield, therefore that area in which the combustion gases give off heat to the casing at the end of the compression and during the combustion whereas 0 the hotter cooling medium cools the area of the casing inclusive the outlet channel in which the combustion gases give off heat during the expansion and exhaust cycle.
  • the cooling media of the two cooling circulations enter into the casing at adjacent places of the two areas, then they cool at first the hottest places of the rotary piston internal combustion engine; namely, the vicinity thereof in which the combustion gases are present at the beginning of the expansion cycle, and then flow toward the coolest places for the respective areas thereof.
  • the cooling medium may additionally flow through the housing end parts and possibly the housing intermediate parts in those areas which directly adjoin the area disposed within the casing and traversed by the same, whereas the hotter cooling medium flows through the areas of the end parts and possibly of the intermediate parts adjoining these areas in the direction toward the center longitudinal axis of the rotary piston internal combustion engine.
  • the areas traversed by the cooler cooling medium are thus disposed, as viewed in the direction of the longitudinal axis of the rotary piston internal combustion engine, all one behind the other so that the inlet and outlet of the cooling medium is particularly simple.
  • the heating medium of the vehicle heater can be heated up in an advantageous manner by the hottest cooling medium whereby the heating effect commences particularly rapidly and intensively.
  • Another object of the present invention resides in a cooling system for cooling the housing of a rotary piston internal combustion engine in which not only the cooling medium pump does not have to be selected very large, but also the difficulties in matching the cooling system to the local, individual requirements is farreachingly dispensed with.
  • a further object of the present invention resides in a cooling system for cooling the housing of a rotary piston internal combustion engine, particularly of trochoidal construction, which effectively avoids local overheating by the use of at least two completely separate cooling circulations.
  • Still a further object of the present invention resides in a cooling system for cooling the housing of a rotary piston internal combustion engine which obviates the need for throttling places as well as complicated designs of the passages for the cooling medium.
  • Still another object of the present invention resides in a cooling system for rotary piston internal combustion engines which also improves the heat-up of the cooling medium after a cold start.
  • a further object of the present invention resides in a cooling system for rotary piston internal combustion engines in which the different cooling circulations cool different areas of the housing with differing heat yield so as to optimize the cooling effect and match it to the local requirements.
  • a further object of the present invention resides in a cooling system for a rotary piston internal combustion engine which assures uniform thermal expansion of the housing as well as improved gas-tightness between individual housing parts.
  • Another object of the present invention resides in a cooling system for rotary piston internal combustion engines which also improves the heating effect of the heater of the motor vehicle.
  • FIG. 1 is a cross-sectional view through the casing of a rotary piston internal combustion engine in accordance with the present invention taken at right angle to the engine axis;
  • FIG. 2 is a similar cross-sectional view through an end portion of the same rotary piston internal combustion engine in accordance with the present invention.
  • the casing l of FIG. 1 is delimited toward the inside thereof by a two-arched trochoidal running surface 2, along which slides the rotating piston 4 with its piston corners 5 in the direction of arrow 3.
  • An inlet channel 6 and an exhaust channel 7 are arranged in the casing 1 along one longitudinal side.
  • An aperture 8 for a spark plug (not shown) is provided in the casing 1 along the oppositely disposed longitudinal side while an aperture 9 for an injection nozzle (not shown) is provided between the aperture 8 for the spark plug and the inlet channel 6.
  • Through-passage openings 10 for tie rods are provided distributed over the circumference which hold together the individual housing parts.
  • the casing l is cooled by cooling media of different temperatures flowing in two cooling circulatory systems completely separate from one another.
  • the cooler cooling medium which, for example, has a temperature of C., flows through a cooling chamber 11 disposed in the casing 1 which extends along the entire longitudinal side on which is disposed the spark plug, up to the trochoidal running surface 2.
  • the opening 8 for the spark plug is surrounded by the cooling chamber 11.
  • the inlet channel 12 into the cooling chamber 11 is located at the end thereof, as viewed in the direction of rotation 3 of the piston 4, whereas the outlet channel 13 is disposed at the other end so that the cooling medium flows through the cooling chamber 11 opposite the direction of rotation 3 of the piston 4.
  • a cooling chamber 14 of the second cooling circulatory system whose cooling medium has a temperature of, for example, C., adjoins the cooling chamber 11 in the direction of rotation 3 of the piston 4 and extends up to the inlet channel 6 whereby it surrounds the exhaust channel 7.
  • the inlet channel 15 into the cooling chamber 14 is disposed in proximity to the inlet channel 12 of the other cooling chamber 11 whereas the outlet channel 16 is disposed in proximity of the inlet channel 6.
  • the continuation of this outlet channel 16 is represented by the channel 28 in the end part 17 (FIG. 2) and possibly in the intermediate parts.
  • the cooling medium of the two cooling circulations thus enter into the cooling chambers 11 and 14 within an area in which the combustion gases have the highest temperature and in which the largest heat quantity is thus produced, and flow in the cooling chambers 11 and 14 toward those places in which the smallest heat quantity for the corresponding areas to be cooled is produced.
  • cooling chambers 18 and 19 which belong to the same cooling circulations as the cooling chambers 11 and 14, respectively.
  • the cooling chamber 18 traversed by the cooler cooling medium is disposed directly adjacent the cooling chamber 1 l of the casing I so that all cooling chambers l1, l8 belonging to this cooling circulation are arranged approximately aligned one behind the other as viewed in the direction of the center longitudinal axis 20 (FIG. 2) of the rotary piston internal combustion engine.
  • the same is also true for the inlet channels 21 and outlet channels 22 in relation to the inlet channels 12 and the outlet channels 13 in the casing l.
  • a very simple guidance and conduction of the cooling medium stream results therefrom.
  • the cooling chamber 19 adjoins the cooling chamber 18 in the direction toward the center of the rotary piston internal combustion engine. Ribs 27 arranged therein are to assure a good cooling medium guidance and conduction.
  • the inlet channel 23 is disposed accurately in front or to the rear of the inlet channel 15 within the casing 1 whereas the outlet channel 24 is disposed in proximity of the outlet channel 22.
  • the continuation of the outlet channel 24 is represented by the channel 25 in the casing 1 (FIG. 1).
  • the areas of the end part 17 not cooled by the cooling media of the two cooling circulations are cooled by lubricating oil which emerges out of the bearing of the piston 4 and leaves the housing by way of the aperture 26.
  • the cooler medium not only flows through the chamber 11 in the casing 1 but additionally flows through the end parts 17 and possibly through intermediate parts of a multi-disk construction by way of chambers 18 located in those areas which directly adjoin the area traversed by the cooler cooling medium in the casing 1 by way of chamber 11;
  • the hotter cooling medium in turn, not only flows through the chamber 14 in the casing l, but also through the end parts 17 and possibly intermediate parts of a multi-disk construction by way of chambers 19 located in those areas directly adjoining the areas of the chambers 18 in the direction toward the center longitudinal axis 20 of the rotary piston internal combustion engine.
  • the hottest cooling medium which may be heated by the exhaust gases of the rotary piston internal combustion engine can be used to heat the heating medium of the vehicle heater. (See schematic showing of the vehicle heater in FIG. 1).
  • the casing means having an inwardly facing running surface engageable with outer portions of the lobes of the piston during rotation thereof, the engine including inlet and outlet channels for respectively accommodating entry of combustible materials into the combustion space and exit of exhaust gases from the combustion space, the running surface and piston being so configured and the inlet and outlet channels being so positioned that combustion gases of differing temperatures are in contact with different circumferential portions of the running surface during operation of the engine;
  • said cooling system comprising:
  • a first cooling circuit for accommodating circulation of a first cooling fluid.
  • said first cooling circuit including a first cooling space formed in said casing means and extending adjacent a first portion of the circumference of said running surface with a cooling fluid inlet to said first cooling space positioned adjacent the circumferential portion of the running surface which is in contact with the hottest combustion gases during operation of the engine,
  • said first cooling space extends around the circumference of said running surface in a direction opposite the rotational direction of the piston from said cooling fluid inlet to a cooling fluid outlet positioned adjacent the circumferential portion of the running surface which is in contact with the coolest combustion gases during operation of the engine.
  • said second cooling circuit includes a second cooling space formed in said casing means and extending adjacent a second portion of the circumference of said running surface which is circumferentially spaced from said first portion of the running surface.
  • a cooling system wherein said second cooling space extends in the direction of rotation of the piston from a cooling fluid inlet thereof located adjacent the cooling fluid inlet of said first cooling space to a cooling fluid outlet thereof.
  • said running surface includes openings for said inlet and outlet channels and for said ignition means, wherein the openings for said inlet and outlet channels are disposed at the opposite side of said combustion space with respect to said opening for the ignition means, and wherein said inlets for said first and second cooling spaces are positioned intermediate the opening for the ignition means and the opening for the outlet channel as seen in the direction of rotation of the piston.
  • a cooling system wherein the opening for the outlet channel, the opening for the inlet channel, and the opening for the ignition means are serially arranged with respect to one another as seen in the direction of rotation of the piston.
  • outlet for the second cooling space is disposed at the side of the opening for the outlet channel closest to the opening for the ignition means as seen in the direction of rotation of the piston.
  • said second cooling circuit includes further cooling spaces formed in said casing means between said openings for the inlet and outlet channels and adjacent the outlet for said first cooling space.
  • said second cooling circuit includes further cooling spaces formed in said casing means between said openings for the inlet and outlet channels and adjacent the outlet for said first cooling space.
  • a cooling system according to claim 5, wherein said running surface is of two-arched trochoidal construction, wherein said piston is a three lobed piston, and wherein the first cooling fluid is maintained cooler than the second cooling fluid.
  • a cooling system according to claim 1, wherein said running surface is of two-arched trochoidal con struction, wherein said piston is a three lobed piston, and wherein the first cooling fluid is maintained cooler than the second cooling fluid.
  • a cooling system according to claim 9, wherein said running surface is of two-arched trochoidal construction, wherein said piston is a three lobed piston, and wherein the first cooling fluid is maintained cooler than the second cooling fluid.
  • a cooling system for cooling housing means of a rotary piston internal combustion engine of the type having housing means enclosing a combustion space within which a multi-lobed rotary piston rotates, the housing means including a casing means circumferentially surrounding the piston, the casing means having an inwardly facing running surface engageable with outer portions of the lobes of the piston during rotation thereof, the engine including inlet and outlet channels for respectively accommodating entry of combustible materials into the combustion space and exit of exhaust gases from the combustion space, the running surface and piston being so configured and the inlet and outlet channels being so positioned that combustion gases of differing temperatures are in contact with different circumferential portions of the running surface during operation of the engine; said cooling system comprising:
  • a first cooling circuit for accommodating circulation of a first cooling fluid
  • said first cooling circuit including a first cooling space formed in said casing means and extending adjacent a first portion of the circumference of said running surface with a cooling fluid inlet said first cooling space positioned adjacent the circumferential portion of the running surface which is in contact with the hottest combustion gases during operation of the engine,
  • said housing means includes an end part adjacent said casing means for laterally closing an axial end of said combustion space, wherein said first cooling circuit includes a cooling space formed in said end part, wherein said second cooling circuit includes a cooling space formed in said end part, and wherein the cooling space in said end part of said first cooling circuit is axially aligned and immediately adjacent the first cooling space.
  • cooling space in said end part of said second cooling circuit extends circumferentially adjacent to and radially inwardly of said cooling space in said end part of said first cooling circuit such that both of said cooling spaces in said end part are disposed at the same side of the rotational axis of the piston.
  • a cooling system according to claim 16 wherein the circumferential extent of the cooling space in said end part of said second cooling circuit is greater than the circumferential extent of the cooling space in said end part of said first cooling circuit with the respective inlets and outlets of the cooling space of said second cooling circuit spaced circumferentially outside of the respective inlets and outlets of the cooling space of said first cooling circuit.
  • a cooling system according to claim 15, wherein said running surface is of two-arched trochoidal construction, wherein said piston is a three lobed piston, and wherein the first cooling fluid is maintained cooler than the second cooling fluid.
  • a cooling system further comprising a vehicle heater means, wherein said second cooling circuit includes means for accommodating heat exchange between the second fluid medium and said vehicle heater means, and wherein said second cooling medium is maintained at a higher temperature than is said first cooling medium.
  • a first cooling circuit for accommodating circulation of a first cooling fluid
  • said first and second cooling circuits including respective separate cooling spaces formed in said end part, the cooling space in said end part of said second cooling circuit extending circumferentially adjacent to and radially inwardly of said cooling space in said end part of said first cooling circuit such that both of said cooling spaces in said end part are disposed at the same side of the rotational axis of the piston.
  • said first cooling circuit includes a first cooling space formed in said casing means and extending adjacent a first portion of the circumference of said running surface, and wherein the cooling space in said end part of said first cooling circuit is axially aligned and immediately adjacent the first cooling space.
  • a cooling system according to claim 27, wherein said running surface is of two-arched trochoidal construction, wherein said piston is a three lobed piston, and wherein the first cooling fluid is maintained cooler than the second cooling fluid.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Pistons, Piston Rings, And Cylinders (AREA)
  • Lubrication Of Internal Combustion Engines (AREA)
US295481A 1971-10-09 1972-10-06 Cooling system for the cooling of the housing of a rotary piston internal combustion engine Expired - Lifetime US3921593A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19712150478 DE2150478A1 (de) 1971-10-09 1971-10-09 Kuehlsystem zum kuehlen des gehaeuses einer rotationskolben-brennkraftmaschine

Publications (2)

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USB295481I5 USB295481I5 (enExample) 1975-01-28
US3921593A true US3921593A (en) 1975-11-25

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US295481A Expired - Lifetime US3921593A (en) 1971-10-09 1972-10-06 Cooling system for the cooling of the housing of a rotary piston internal combustion engine

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US (1) US3921593A (enExample)
JP (1) JPS4845706A (enExample)
DE (1) DE2150478A1 (enExample)
FR (1) FR2155675A5 (enExample)
GB (1) GB1396567A (enExample)
IT (1) IT966249B (enExample)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4021163A (en) * 1974-10-11 1977-05-03 Toyo Kogyo Co., Ltd. Rotary-piston engine housing
US4037999A (en) * 1975-03-15 1977-07-26 Audi Nsu Auto Union Aktiengesellschaft Liquid-cooled rotary piston internal combustion engine with housing
US6139290A (en) * 1998-05-29 2000-10-31 Masterson; Frederick Method to seal a planetary rotor engine
US6481989B2 (en) * 2000-05-27 2002-11-19 Brandenburgische Forschungs-Und Entwicklungsgesellschaft Cottbus Mbh Trochoidal design rotary piston engine and method of making same

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112127990A (zh) * 2020-10-27 2020-12-25 湘潭大学 一种多向冷却的转子发动机液冷装置及系统

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3298330A (en) * 1964-04-22 1967-01-17 Yanmar Diesel Engine Co Rotary piston engine
US3444845A (en) * 1966-02-23 1969-05-20 List Hans Internal combustion engine

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3298330A (en) * 1964-04-22 1967-01-17 Yanmar Diesel Engine Co Rotary piston engine
US3444845A (en) * 1966-02-23 1969-05-20 List Hans Internal combustion engine

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
"Curtiss-Wright's Experimental Rotating Combustion Engines," by Dr. Max Bentele, (Received 10-14-63) *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4021163A (en) * 1974-10-11 1977-05-03 Toyo Kogyo Co., Ltd. Rotary-piston engine housing
US4037999A (en) * 1975-03-15 1977-07-26 Audi Nsu Auto Union Aktiengesellschaft Liquid-cooled rotary piston internal combustion engine with housing
US6139290A (en) * 1998-05-29 2000-10-31 Masterson; Frederick Method to seal a planetary rotor engine
US6481989B2 (en) * 2000-05-27 2002-11-19 Brandenburgische Forschungs-Und Entwicklungsgesellschaft Cottbus Mbh Trochoidal design rotary piston engine and method of making same

Also Published As

Publication number Publication date
JPS4845706A (enExample) 1973-06-29
IT966249B (it) 1974-02-11
GB1396567A (en) 1975-06-04
FR2155675A5 (enExample) 1973-05-18
DE2150478A1 (de) 1973-04-12
USB295481I5 (enExample) 1975-01-28

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