Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
  • F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
  • F04C18/08—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
  • F04C18/12—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type
  • F04C18/14—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with toothed rotary pistons
  • F04C18/16—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with toothed rotary pistons with helical teeth, e.g. chevron-shaped, screw type
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01C—ROTARY-PISTON OR OSCILLATING-PISTON MACHINES OR ENGINES
  • F01C1/00—Rotary-piston machines or engines
  • F01C1/08—Rotary-piston machines or engines of intermeshing engagement type, i.e. with engagement of co- operating members similar to that of toothed gearing
  • F01C1/082—Details specially related to intermeshing engagement type machines or engines
  • F01C1/084—Toothed wheels
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01C—ROTARY-PISTON OR OSCILLATING-PISTON MACHINES OR ENGINES
  • F01C1/00—Rotary-piston machines or engines
  • F01C1/08—Rotary-piston machines or engines of intermeshing engagement type, i.e. with engagement of co- operating members similar to that of toothed gearing
  • F01C1/12—Rotary-piston machines or engines of intermeshing engagement type, i.e. with engagement of co- operating members similar to that of toothed gearing of other than internal-axis type
  • F01C1/14—Rotary-piston machines or engines of intermeshing engagement type, i.e. with engagement of co- operating members similar to that of toothed gearing of other than internal-axis type with toothed rotary pistons
  • F01C1/16—Rotary-piston machines or engines of intermeshing engagement type, i.e. with engagement of co- operating members similar to that of toothed gearing of other than internal-axis type with toothed rotary pistons with helical teeth, e.g. chevron-shaped, screw type
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
  • F04C2240/00—Components
  • F04C2240/20—Rotors
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
  • F04C2240/00—Components
  • F04C2240/30—Casings or housings
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
  • F04C2240/00—Components
  • F04C2240/60—Shafts

Definitions

• the invention relates generally to a pressure reducer (also called Popepander”) for rotary internal combustion engines, and more specifically, to a pressure reducer having intermeshing rotors.
• a pressure reducer also called Popepander
• Rotary internal combustion engines take advantage of a cycle of distinct intake, compression, combustion-expansion and exhaust processes as in a four stroke cycle. Pressure reducers are used in the combustion cycle for expanding gases passing through the engine before they are exhausted.
• a stator is in the shape of a two-lobed epitrochoid and a rotor is a trochoid.
• This symmetrical trochoid rotor revolves on a large bearing on the crank arm of the crankshaft which is an eccentric on the driveshaft.
• the three tips of the trochoid rotor have tip seals.
• a later development of a rotary internal combustion engine is described in US 3, 724, 427.
• a plurality of segregated chambers are arranged in communicating relation with one another for compression, combustion and expansion of the gases.
• Each of the chambers comprise a rotary pump for example in the form of a pair of multi-lobed intermeshing rotors mounted on two parallel drive shafts within a housing.
• the rotors together with the housing establish chambers, the volume of which is changing when the rotors are rotating with in the housing, such that the changing volume can cause the expansion of the combustion gases.
• Such arrangements often are subject to a high level of wear, which impacts the expansion capacity of the engine.
• a pressure reducer for a rotary internal combustion engine comprises a housing, which accommodates a first shaft and a second shaft running parallel to each other through the housing. Further the pressure reducer comprises a first rotor on the first shaft and a second rotor on the second shaft.
• the first rotor and the second rotor are configured in a meshing arrangement, when the first shaft and the second shaft rotate in counter direction to each other.
• the first rotor comprises several radial extensions having non-circular convex shaped outer flanks
• the second rotor comprises several radial wings defining indentations in between two wings having a non-circular concave shaped surface.
• the pressure expansion chamber is defined by a volume between a convex shaped flank of one of the extensions of the first rotor and a concave shaped surface of one of the indentations of the second rotor.
• the convex flank lies opposite of the convex surface, when the extensions reaches into the indentation.
• An outer tip of the radial extension abuts on the concave shaped surface of the indentation and an outer edge of the indentation, that means an edge of the wing, abuts on the convex shaped surface of the extension.
• the shapes of the convex flanks and the concave surfaces are realized such, that in rotation the indentation and extension contact each other simultaneously at only two distinct contact points at said outer tip of the extension on the concave shaped surface on the one end and at the outer edge of the indentation on the convex shaped flank of the extension on the other end.
• the expansion of the pressure expansion chamber is used to reduce the pressure of gases trapped with in the chamber during the rotation of the to rotors within the housing.
• the pressure expansion provided by the pressure expansion chamber according to the invention guarantees a reliable pressure release of high efficiency due to the well-defined work space between the meshing rotors.
• the housing comprises an inlet opening culminating in an inlet chamber within the housing.
• the inlet chamber is defined by a convex flank of the first rotor, a concave surface of the second rotor and a first inner surface of the housing.
• the extension of the convex flank and the indentation of the concave surface are not yet in a meshing engagement .
• the extension reaches into the indentation.
• the pressure expansion chamber is established and the gas present in the inlet chamber is trapped within the pressure expansion chamber.
• the housing On the opposite side of the inlet opening the housing comprises an outlet opening out of an outlet chamber defined within the housing.
• the outlet chamber is defined by a further convex flank of the first rotor, a further concave surface of the second rotor and a second inner surface of the housing.
• the second inner surface is opposing the first inner surface.
• the housing has a first portion of at least half cylindrical shape for housing the first rotor and a second portion of at least half cylindrical shape for housing the second rotor.
• the first and the second portions are connected to realize the housing.
• the housing has an elongated cross section with rounded opposite ends.
• the first and the second portions show a cylindrical shape for more than half of their circumference the housing will have a tapered or 8-like shape.
• the inner surface of the half cylindrical portions of the housing are flush with outer ends of the wings and the tips of the extensions, respectively.
• the number of indentations on the second rotor is larger than the number of extensions on the first rotor. That means the rotors show a design, which results in an enhancement of the expansion efficiency.
• the second rotor comprises two wings resulting in two indentations with a concave surface and the first rotor comprises four, five, six or seven extensions resulting in an equal number of convex flanks.
• the second rotor may have four wings with four indentations in between them and five, six or seven extensions.
• the abutting surfaces and flanks of the first and second rotor are lubricated to seal the pressure expansion chamber and enclose the gas in the chamber.
• an oil film on the convex flanks and the concave surfaces can be used as lubricant .
• meshing toothed wheels are fixed on the first shaft and on the second shaft for synchronizing the revolting movement of the shafts.
• a first toothed wheel is fixed on the first shaft and a second toothed wheel is fixed on the second shaft engaging with the first toothed wheel.
• the interacting toothed wheels allow for a precise coordination of the rotors, which is important in particular in case the pressure reducer is set up with an asymmetric rotor design as described above.
• the first shaft and the second shaft comprise means for reducing a pressure exerted on the shafts during operation of the rotary internal combustion engine, in particular means for reducing a mechanical pressure on the shafts.
• the means for reducing the pressure include for example ball bearings for the shafts, bearings having a low friction surface, like synthetic material bearings, or an enlargement of the bearing surface between the rotating shafts and stationary elements of the housing.
• Other means for reducing a pressure exerted on the first shaft and the second shaft during operation of the rotary internal combustion engine are possible.
• a rotary internal combustion engine according to the present invention takes advantage of a pressure reducer as described above.
• a rotary internal combustion engine using such a pressure reducer has an enhanced pressure expansion after the combustion step of the engine cycle resulting in a high efficiency level of the engine.
• the inlet chamber is connected to a combustion chamber of the engine to directly facilitate the expansion of the combustion gases.
• Fig. 1 a schematic cross section of a pressure reducer according to the invention
• Fig. 2 a three-dimensional view of the pressure reducer shown in figure 1. Description of a preferred example of the invention
• FIG. 1 shows a cross-sectional view of a pressure reducer according to the invention.
• the pressure reducer comprises a housing 1 with a first half cylindrically shaped portion 2 and a second half cylindrically shaped portion 3.
• the portions 2 and 3 of the housing 1 are connected, although in figure 1 they are depicted unconnected due to an inlet opening 4 into the housing and an outlet opening 5 out of the housing .
• the first half cylindrically shaped portion 2 of the housing 1 accommodates a first shaft 6 carrying a first rotor 7.
• the second half cylindrically shaped portion 3 accommodates a second shaft 8 carrying a second rotor 9.
• the shafts run parallel through the housing 1 and can be supported by bearings in opposing walls of the housing 1.
• the first rotor 7 comprises several radial extensions or lobes 10.
• the rotor 7 has four extensions 10.
• the extensions or lobes 10 have non-circular, elliptical or ovoidal, convex shaped outer flanks 11 extending from a central mounting hub of the rotor 7 on shaft 6, said elliptically shaped flanks 11 joining radially in to form an outer tip 12 of each extensions or lobes 10.
• the second rotor 9 comprises several radial wings 13 extending from a central mounting hub of the second rotor 9 on shaft 8.
• the rotor 9 has six radial wings 13.
• the wings 13 define indentations or grooves 14 between each other.
• the indentations or grooves 14 are designed with a non-circular, elliptical or ovoidal, concave shaped surface 15.
• the wings 13 terminate in edges 16 at their radially outer most points.
• the first shaft 6 and the second shaft 8 are distanced in the housing 1 and the radial extensions 10 of the first rotor 7 and the indentations 14 of the second rotor 1 are respectively configured in such a way that said extensions 10 mesh in the indentations 14 in a non-mating fashion, i.e. the radius or curvature of the flanks 11 differ from that of the inner surface of the grooves or indentations 14, more specifically the radius or curvature of the flanks 11 is larger than that of the inner surface 15 of the grooves or indentations 14 such that, as represented in fig.
• a pressure expansion chamber 17 is established upon meshing of an extension 10a in an indentation or groove 14a between a flank 11a of said extension 10a and the inner surface 15a of said indentation or groove 14a.
• the outer tip 12a of the radial extension 10a abuts at a first point on the concave shaped surface 15a of the indentation 14a, while an outer edge 16a of the indentation 14a abuts at a second point different from said first point on the convex shaped flank 11a of the extension 10a, defining a croissant-shaped inner volume forming the expansion chamber 17 between said extension 10a of the first rotor 7 and concave surface 15a of the indentation 14a.
• the tip 12a slides over the concave surface 15a of the indentation 14a and the edge 16a of the indentation 14a slides along the convex flank 11a, while the shafts 6 and 8 rotate in counter direction.
• the tip 12a contacts the concave surface 15a shortly behind the edge 16a.
• the tip 12a slides down the concave surface 15a.
• the edge 16a slides along the convex flank 11a from the tip 12a to the bottom of the flank.
• the outer flank 11a of an extension 10a of the first rotor 7 and the inner concave surface 15a of a corresponding indention 14a of the second rotor 9 are contacting each other simultaneously during a meshing engagement of the rotor 7, 9 at only two distinct contact points at said outer tip 12a of the radial extension 10a on the concave shaped surface 15a on the one end and at the outer edge 16a of the indentation 14a on the convex shaped flank 11a of the extension 10a on the other end.
• an expansion chamber 17 is permanently defined and arranged therebetween, the volume of which varies upon rotation of the rotors 7, 9 until disengagement of the extension 10a with the indentation 14a.
• the meshing between rotors 7, 9 never results in either a continuous linear contact or a single contact point between mating surfaces of the extensions 10 of the first rotor 7 and corresponding indentations 14 of the second rotor 9.
• This specific configuration of the rotors 7, 9 of the pressure expander of the invention and relative movement in operation results in expanding the volume of the pressure expansion chamber 17 upon rotation in opposite directions of the rotors 7, 9.
• the inlet opening 4 of the housing 1 culminates in an inlet chamber 18, which is defined by a convex flank 11 of the first rotor 7, a concave surface 15 of the second rotor 9 and a first inner surface 19 of the housing.
• the housing 1 comprises an outlet chamber 20 defined by a convex flank 11 of the first rotor 7, a concave surface 15 of the second rotor 9 and a second inner surface 21 of the housing 1 on the opposite side of the first inner surface 19.
• gas enters the inlet opening 4 into inlet chamber 18.
• the revolution of the shafts 7 and 9 moves the convex flank 11 towards the concave surface 15, which define the inlet chamber 18 towards each other until the tip 12 abuts on the concave surface 15 and traps the gas in the pressure expansion chamber 17.
• revolution enlarges the volume of the pressure expansion chamber 17 and the gas inside the chamber expands.
• Figure 2 shows a three-dimensional semi-transparent view of the housing 1 of the pressure reducer according to the invention.
• the first shaft 6 carrying the first rotor 7 and the second shaft 8 carrying the second rotor 9 are supported in bearings 30.
• the inlet opening 4 of the housing 1 is located at the same axial position than the rotors 7 and 9.
• the housing accommodating the shafts 6 and 8 and the rotors 7 and 9 represents a compact construction unit for the rotary internal combustion engine that is made up of only a few parts and can be produced at low costs. Further the unit can be easily exchanged and/ or maintained.
• the bearings 30 may comprise means for reducing a pressure exerted on the first shaft 6 and the second shaft 8 during operation of the rotary internal combustion engine.
• ball bearings may be arranged between the housing 1 and each of the shafts 6 and 8.
• Other means for reducing the pressure on the shafts are known to a person skilled in the art, like for example an advantageous static construction of the housing and the shafts.
• the pressure reducing means helps to decrease the pressure exerted on the shafts 6 and 8 during the process of expanding the volume of the pressure expansion chamber 17.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Hydraulic Motors (AREA)
• Rotary Pumps (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=60164544

Family Applications (1)

Country Status (4)

Families Citing this family (1)

Family Cites Families (6)

• 2018
  • 2018-04-20 CA CA3060013A patent/CA3060013A1/en not_active Abandoned
  • 2018-04-20 WO PCT/EP2018/060228 patent/WO2018193112A1/en unknown
  • 2018-04-20 EP EP18718165.6A patent/EP3612720A1/de not_active Withdrawn
  • 2018-04-20 US US16/605,861 patent/US20210123345A1/en not_active Abandoned

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