EP1134381A1 - Piston machine - Google Patents

Abstract

The internal combustion motor has a gearing between the pistons and the crankshaft with a swing lever (13,18) on a center pivot axis (14,20) in a gear housing (25). A rotating roller (15,19) is at the lever ends, on axes at right angles to the lever swing axis, to ride on a path (16,24) at the shaft (17) between them. The ends of the levers are linked to the pistons (7-10) by connecting rods (12).

Description

The present invention relates to a piston engine according to the preamble of claim 1.

Such piston machines are known. In particular, reciprocating engines are known by the Otto or Diesel process, in which the linear reciprocation of the pistons via connecting rods, which with a Interacting crankshaft can be converted into a rotational movement. The movement of the pistons is thus sinusoidal, the sequence of movements the piston cannot be influenced, an optimization of the combustion process, for example in the case of internal combustion engines with regard to Low pollutant combustion cannot be achieved.

In EP-A-0 702 128 a mechanism is shown by means of which the linear reciprocation of the piston over a cam is converted into a rotational movement of a shaft. By using it a cam disc can show the movement characteristics of the piston the desired process can be adjusted and optimized by the one shown here However, the arrangement is subject to changing forces, in particular transverse forces, on the walls of the piston, which negatively affects the frictional relationships affects and thus increases the wear of the corresponding friction surfaces becomes. Furthermore, the cam disc has a large difference between largest radius and smallest radius, whereby the rolling on it Roll when the shaft is essentially a constant angular velocity during a revolution of the shaft from a maximum speed slowed down a minimum speed and back to maximum speed is accelerated. It happens because of fast running engines the inertia of the mass of the roll for sliding movements between the roll surface and cam surface, which also causes wear here becomes relatively large.

From publication No. WO 88/05858 is an internal combustion engine removable, in which the pistons interact in pairs are arranged, and their linear reciprocating movement over to the Piston-mounted rollers are transferred to a curve that takes the form of a Has ring surface, which is provided with ridges and depressions, and the is firmly connected to the shaft. Through this choice of curved surfaces, the Speed fluctuation of the rollers in the use described above of cams is very large, significantly reduced. By using it of cambered cylindrical rollers, which means that the load capacity is very high drops sharply, and thereby the drilling movement that occur with cylindrical rollers would, can be avoided, remains an axial shift of the rollers in the slopes of the cam still exist, making a relative major wear and tear cannot be prevented. Furthermore, also works this embodiment, a reaction force via the piston to the cylinder wall, which also creates a lot of friction here.

The publication WO 98/04820 also describes an internal combustion engine shown, which is constructed essentially the same as that previously described, being instead of a curved path that acts as a curved surface is embedded in a hollow cylinder, a rib is used, the circumferential is placed on a cylinder body. With this arrangement, however get exactly the same disadvantages as the one previously described Embodiment.

The object of the present invention is now one To design the piston engine so that the conversion of the linear reciprocation the piston get into a rotary motion of the shaft and vice versa can be that the friction and wear are as low as possible can be held. Furthermore, the structure of what is required for this Mechanism to be simple and inexpensive.

According to the invention this object is achieved by the Features listed claim 1.

By using a swivel lever, the reaction forces can be optimally taken up by the housing, so that practical no lateral forces act on the pistons.

An advantageous embodiment of the invention is that the The path on which the rollers roll runs in a hollow spherical shell, the Center at the intersection of the pivot axis of the pivot lever with the axis of rotation the shaft lies, and the surface of the track in the radial direction against that Center is directed, and that the two rollers are in the shape of a truncated cone have, the tip of the cone defined by the truncated cone also lies in the center defined above. This ensures an optimal rolling process reached the rollers on the track, there is no drilling movement, one axial displacement of the roller is avoided, the load capacity is due to the line contact between roll and web big, the wear becomes extreme kept to a minimum.

Another advantageous embodiment of the invention consists in that the respective coupling rod is firmly connected to the corresponding piston and in the area in which it is articulated on the swivel lever in a linear guide is guided, which is aligned parallel to the cylinder axis is. This ensures optimal guidance of the pistons in the cylinder Friction between piston and cylinder is very low, which leads to wear and the efficiency is improved accordingly.

The articulation between the pivot lever and Coupling rod designed so that the pivot point in the pivot lever essentially against its pivot axis and slidable away from it is stored. This allows the arc movement of the pivot lever and the Linear movement of the coupling rod compensated without an additional intermediate link become.

Another advantageous embodiment of the invention consists in that the pivot lever is formed from a frame between the two parallel legs the shaft runs and the two legs with each are equipped with a journal, through which the pivot axis is formed is and the trunnions are each stored in a bearing, which bearings each are held in a tab, which tabs are fixed to the housing are connected. This construction ensures optimal absorption of the Forces resulting from the torque acting on the swivel lever reached, the friction can be kept extremely low.

Advantageously, the bearings in the tabs with the Housing are firmly connected, adjustable, which makes the pivot lever becomes adjustable and the two rollers interact optimally with the web can.

The shaft is advantageously provided with means for transmitting the Rotational movement equipped on other transmission elements, for example to control the valves and to drive other units.

Another object of the invention is a valve device for opening and closing inlet and outlet openings in one Cylinder of a piston engine, in particular a piston engine previously described way of creating, which is simple in construction and which has little wear.

According to the invention this object is achieved by the Claim 8 features listed. By using a sealing plate, which is hinged to a pivotable lever, and which in the closed state covers the respective opening in the cylinder, an optimal seal achieved without complex surfaces being ground on each other have to.

The sealing surface of the sealing plate is advantageously flat, the corresponding area of the cylinder surface that the respective opening surrounds can also be flat, these surfaces can in easily obtained.

There is a further advantageous embodiment of this valve device in that the sealing plate with respect to the pivot axis of the pivotable Lever is held so that the sealing surface of the sealing plate adjusts itself automatically with respect to the area surrounding the respective opening. This ensures optimal tightness.

There is a further advantageous embodiment of this valve device in that a counterweight is attached to the sealing plate, which is arranged such that during the opening and closing movement of the sealing plate this is essentially stationary with respect to the pivot lever. There practically no movement takes place between the sealing plate and the swivel lever, it is not necessary to provide lubrication, which makes the structure is significantly simplified.

Another advantageous embodiment of the invention consists in that at least the sealing plate is made of a ceramic material is. This provides the required temperature resistance without cooling, a warpage and thermal stress in the sealing plate caused by the cooling could result, are therefore eliminated.

Fig. 1 in schematischer Darstellung eine als Wärmemotor ausgebildete erfindungsgemässe Kolbenmaschine;

Fig. 2 eine Ansicht einer Gruppe der Zylinderanordnung in konstruktiver Ausgestaltung, zum Teil im Schnitt, des Wärmemotors gemäss Fig. 1;

Fig. 3 eine Schnittdarstellung durch den Schwenkhebel entlang Linie III-III der Darstellung gemäss Fig. 2;

Fig. 4 eine Schnittdarstellung entlang Linie IV-IV durch den Schwenkhebel gemäss Fig. 3;

Fig. 5 eine Ansicht auf eine erste Ausführungsform einer Ventileinrichtung;

Fig. 6 eine Draufsicht auf die Ventileinrichtung gemäss Fig. 5, zum Teil im Schnitt;

Fig. 7 eine Ansicht auf eine weitere Ausführungsform einer Ventileinrichtung; und

Fig. 8 eine Draufsicht auf die Ventileinrichtung gemäss Fig. 7, zum Teil im Schnitt.

Embodiments of the devices according to the invention are explained in more detail below by way of example with reference to the accompanying drawing. It shows

1 shows a schematic representation of a piston engine according to the invention designed as a heat motor;

FIG. 2 shows a view of a group of the cylinder arrangement in a constructive configuration, partly in section, of the heat engine according to FIG. 1;

3 shows a sectional illustration through the pivoting lever along line III-III of the illustration according to FIG. 2;

4 shows a sectional view along line IV-IV through the pivoting lever according to FIG. 3;

5 shows a view of a first embodiment of a valve device;

FIG. 6 shows a top view of the valve device according to FIG. 5, partly in section;

7 shows a view of a further embodiment of a valve device; and

Fig. 8 is a plan view of the valve device of FIG. 7, partly in section.

The piston engine designed as a heat engine, as shown in FIG. 1 is shown schematically, comprises two groups 1 and 2 of four cylinders each 3, 4, 5 and 6. In each cylinder 3, 4, 5 and 6 there is a piston 7, 8, 9 or 10 arranged linearly. Each cylinder 3 to 6 is with one Valve device 11 equipped with which the inlet and outlet openings of the respective cylinder 3 to 6 can be opened and closed, which valve devices 11 will be described in detail later.

A coupling rod 12 is attached to each of the pistons 7, 8, 9 and 10. The coupling rod 12, which is connected to the piston 7, which is in the cylinder 3 moves, is hinged to an end portion of a pivot lever 13. The coupling rod 12 of the piston 8, which moves in the cylinder 4, is on the other end portion of the pivot lever 13 articulated. The pivot lever 13 is pivotable centrally about a pivot axis 14, which is in the housing of the piston machine is held, as will be described later.

Is also at the two end regions of the pivot lever 13 a roller 15 is arranged, the axes of rotation of which are perpendicular to each Stand pivot axis 14 of the pivot lever 13. The rollers 15 roll on one Path 16, which is fixedly connected to a centrally arranged shaft 17, and which is provided with elevations and depressions, as described later becomes.

In the same way, the coupling rod 12 of the piston 9 is in the cylinder 5 is movable back and forth at one end of another Pivoted lever 18 articulated, while the coupling rod 12 of the piston 10, which can be moved back and forth in the cylinder 6, further at the other end region Swivel lever 18 is articulated. This further pivot lever 18 is also Equipped with rollers 19 in the same way as the pivot lever 13. The further pivot lever 18 is pivotable about the pivot axis 20, the axes of rotation the rollers 19 are also perpendicular to this pivot axis 20, which is also held on the housing.

The rollers 19 also roll on a web 24 which is fixed to the Wave 17 is connected.

The operation of this heat engine is described below. By rotating the shaft 17 is alternately by the Pistons 7 and 8, respectively, via the coupling rods 12 and the pivot lever 13 in the cylinders 3 and 4 can be moved back and forth via an intake duct 21 a gaseous medium is sucked in and compressed, the valve device 11 opens and closes the inlet and outlet openings in a controlled manner. The compressed gas is expelled into a high pressure chamber 22. Through the Arrangement of four cylinders 3 and 4 (two per group 1 and group 2) and the appropriately designed and trained track 16 has each of the Pistons 7 and 8 each slightly over a quarter of a revolution of the shaft 17 available for pushing out the compressed gas, which makes the Pushing out can take place at low gas speed and the flow losses are correspondingly low. The course of the web 16 with their Raises and depressions is the characteristic of the valve device 11 and the corresponding flow conditions, so that from cylinders 3 and 4 are practically continuous and almost uniform Gas flow flows into the high pressure chamber 22.

Heat is supplied to the compressed gas in the high-pressure chamber 22, what, for example, by burning an appropriate fuel can take place in the high pressure chamber 22, represented by reference numerals 23. The heat can also be supplied by a heat exchanger, which can be operated, for example, by an external heat source. This external heat source can be operated practically as desired. By this supply of heat expands the combustion gas and flows over it Valve device 11 into cylinders 5 and 6. The gas expands, the pistons 9 and 10 alternate back and drive over the coupling rod 12, via the further pivot lever 18, the rollers 19 and the web 24 Wave 17 on. The expanded gas leaves cylinders 5 and 6 through the valve device 11 controlled outlet openings. Also in cylinders 5 and 6, the combustion gas is again filled by slow Overflow and with little loss of energy. The valve devices 11 are in a known manner on the shaft 17 with the corresponding Drive mechanism controlled.

In such a heat engine, for example, the gas in the high pressure chamber at a pressure of approx. 15 to 20 bar to a temperature of about 1500 Kelvin. The stroke volume of the cylinders the heated gas is about 2.5 times the stroke volume the cylinders that suck in and compress the gas. The temperature of the escaping gas is then about 470 Kelvin.

In the intake duct 21 in the area of the valve devices 11 throttle disks 56 known per se (FIG. 2) can be used. Appropriate Throttle disks are also in the area of the valve devices 11 the cylinders 5 and 6 used. This allows the filling of cylinders 3 and 4, which suck in and compress the gas. With not When completely filled, the compression pressure becomes smaller, resulting in a smaller one Pressure in the combustion chamber. So much is in the combustion chamber Heat is supplied in connection with the removal of the heated gas a constant pressure is set in cylinders 5 and 6. This pressure can measured and regulated via the heat supply. With the appropriate Throttle disks can prevent gas from entering cylinders 5 and 6 can flow back.

The example described above uses an open gas circuit described. Of course, it is also conceivable to close the heat engine Design cycle. Here, the heat supply done by a heat exchanger, which for example via solar energy is heated. The gas expelled from cylinders 5 and 6 could be supplied to a low pressure chamber in which the gas Heat is removed, after which this gas is returned to cylinders 3 and 4 could be.

From Fig. 2, in which a group 1 of those described in Fig. 1 Piston engine is shown, it can be seen how the cylinders 3, 4, 5 and 6 and the shaft 17 are arranged in the housing 25. Also on the housing 25 is the pivot axis, not shown, mounted, as will be described later, about which the pivot lever 13 is pivotable. As already mentioned, they are Rollers 15 are each rotatably mounted on an end region of the pivot lever 13 and roll on the web 16. This track 16 is designed as a kind of ring surface, which is formed by a hollow spherical shell 26. This hollow spherical shell 26 has a flattened part 27 on which, for example, a gear 28 is fixed, and which is fixed to the shaft 17. The center the hollow spherical shell 26 is located at the intersection of the pivot axis 14 of the pivot lever 13 with the axis of rotation 29 of the shaft 17. This has the in the hollow spherical shell 26 extending track 16, the elevations and depressions always the same distance from the center mentioned above.

These hollow spherical shells 26 with the flattened parts and the further gears 28, etc. mounted on the shaft 17 serve simultaneously as a flywheel, which ensures that the piston machine runs smoothly is.

The surface of the web 16 is always against that in the radial direction Center directed. The rollers 15, which roll on the web 16, have the shape of a truncated cone, the tip of which is defined by the truncated cone Kegels is also in the center.

This arrangement results for the rollers 15 on the whole Length of the web 16 always optimal rolling conditions, so it is created no drilling movement of the roll with respect to the web, an axial shift the roll is avoided, the wear is therefore very low. By steady Line contact between roller 15 and track 16 is also the load capacity large.

In the same way, the rollers 19 roll on the further pivot lever 18 are attached, on a correspondingly shaped track 24, whereby pistons 9 and 10 (FIG. 1) are moved back and forth in cylinders 5 and 6, so that a detailed description can be dispensed with. Also here is an optimal rolling process of the rollers 19 on the corresponding Lane 24 reached.

The coupling rods 12 are with the pistons 7 and 8, as shown in FIG. 2 is shown, firmly connected. The coupling rods are also in the same way 12 firmly connected to the pistons 9 and 10, which are in the cylinders 5 and 6 to move back and fourth. Therefore, in the area of the respective pivot lever 13 or 18, the coupling rod 12 each guided in a linear guide 30. The connection between coupling rod 12 and pivot lever 13 or 18 is designed that the articulation point essentially against the pivot axis 14 or 20 of the pivot lever 13 or 18 to and from it is mounted so that the arc movement of the pivot lever 13 or 18 and the linear movement of the coupling rod 12 without an additional intermediate member can be compensated. This ensures that pistons 7, 8, 9 and 10 in the respective cylinders 3, 4, 5 and 6 reached.

As can also be seen from FIG. 2, the shaft 17 can still drive further units, as shown in the lower part of FIG. 2, such as the control of the valve devices 11.

As can also be seen from FIG. 2, the piston surfaces the pistons 7, 8, 9 and 10 are provided with a heat-insulating layer 57 his. Accordingly, the high pressure chamber 22 (Fig. 1) with heat insulating Material lined.

From Fig. 3 it can be seen that the pivot lever 13 and the other Swivel lever 18 has the shape of a frame 31. This frame 31 is formed from two legs 32 and 33, between which the shaft 17 extends. A bearing journal 34 is fastened to each of the two legs 32 and 33, which engages in a bearing 35, which is each held in a tab 36, which tab 36 is attached to the housing. Through these two journals 34 thus the pivot axis 14 and 20 is formed.

By using a swivel lever for motion transmission only two rollers between two pistons and the web required, which simplifies the construction. To an optimal location of the To be able to reach rolls with respect to the web, the bearings 35, in which the pivot pins of the pivot lever are mounted in a known manner be adjustable, for example by means of adjusting screws.

The two legs 32 and 33 are at the end region with a connecting web 37 connected to each other. In this connecting web 37 is a Bearing pin 38 attached, on which the roller 15 and 19 rotatable and against axial displacement is stored securely. There are two on the bearing pin 38 Fastened webs 39 and 40, each provided with a longitudinal slot 41 are. A bearing bush 42 is inserted into these longitudinal slots 41 so as to be longitudinally displaceable, in which an axle piece 43 is held. This axis piece 43 is on both sides guided in the linear guides 30. Is held on the bearing bush 42 each the corresponding end of the coupling rod 12. Through this storage is the arcuate pivoting movement of the pivot lever 13 or 18 to the Linear movement of the coupling rod 12 can be compensated.

5 and 6 show a valve device 44 with which one Inlet or outlet opening 45 opened in a cylinder of a piston engine and can be locked. This valve device 44 consists of a pivot axis 46 to which a lever 47 is attached. The pivot axis 46 is pivotable and stationary with respect to the corresponding cylinder stored. The pivotable lever 47 has a slot-shaped recess 48 provided, in which a web 49 comes to rest, which on the sealing plate 50th is attached. The pivotable lever 47 and the web 49 are continuous Provide bore in which an axle piece 51 is inserted. in the the central region, the axle piece 51 has a spherical shape, on which the web 49 is mounted. By the proposed game between the slit-shaped Recess 48 and the web 49, this is both by the Axis piece 51 formed axis as well as a transverse axis swiveling a small amount.

The sealing plate 50, which in the closed state the inlet or Closes outlet opening, is supported with its flat sealing surface 52 on the surface 53 of the cylinder surface surrounding the respective opening 45. Due to the possibility of pivoting the web 49 with respect to the axle piece 51 the sealing surface 52 of the sealing plate 50 adapts to the surface 53. This makes the seal optimal, the processing of the sealing surfaces is corresponding simple. This configuration also allows thermal expansion of the corresponding material.

As already mentioned, opening and closing takes place via the Swiveling the pivot axis 46. The drive mechanism can one have known structure, the use of a pivot lever would also be conceivable with a roll that rolls on a track as it moves the Piston is used in the previously described piston machine.

Because these movements are very fast piston engines done quickly, it should be avoided that the sealing plate 50 with respect to each other of the axle piece 51 moved too much. Therefore is on the web 49 on the sealing plate 50 opposite side a counterweight 54 is arranged. This Counterweight 54 is arranged and designed so that the opening and closing movement of the valve device, the sealing plate 50, the web 49 and the counterweight 54 practical because of the inertia with respect to the axle piece 51 not moved. Thus, it is also not necessary for a lubrication device is provided with which the bearing of the sealing plate is lubricated should be. This simplifies the construction of this valve device.

In order to be able to omit cooling, the material of the Sealing plate 50, the web 49 and the counterweight 54 selected accordingly be, for example, it is advantageous to make this part from a ceramic To manufacture material.

7 and 8 is an embodiment of a valve device 44, which has essentially the same structure as the previously described but the axle pin 51 is no longer spherical Middle piece is provided and thus the sealing plate 50 with respect to this axis piece 51 is only pivotable about an axis and that the pivotability around the axis perpendicular to the axis piece 51 by a further bolt 55 is reached, around which the pivotable lever 47 about the pivot axis 46 is slightly pivotable. This also optimally achieves that the flat sealing surface 52 of the sealing plate 50 adapts to the surface 53. Here too, attaching the counterweight 54 ensures that the sealing plate 50, the web 49 and the counterweight 54 with respect to the axes of rotation move as little as possible so that lubrication is also avoided here can be.

This valve device 44 can be used for piston machines of any kind are used, for example, heat engines, as previously described heat pumps, but also compressors etc.

Claims (12)

Piston machine with a housing (25) which has at least two cylinders (3, 4; 5, 6) with inlet openings and outlet openings which can be opened and closed by means of controllable valves, in which cylinders (3, 4, 5, 6) each Piston (7, 8, 9, 10) is linearly reciprocable, and comprises at least one shaft (17) rotatably mounted in the housing (25), and in which the piston (7, 8, 9, 10) and the shaft (17) are coupled to one another via a gear device, by means of which gear device the linear back and forth movement of the pistons (7, 8, 9, 10) can be converted into a rotational movement of the shaft (17), or the rotational movement of the shaft (17) can be converted into a linear reciprocating movement of the pistons (7, 8, 9, 10), characterized in that the gear device comprises a pivoting lever (13; 18) which is pivotable about a pivot axis (14; 20) arranged in the center, which is mounted in the housing (25) and on which pivot lever (13; 18) a rotatable roller (15; 19) is arranged, the axes of rotation of which are perpendicular to the pivot axis (14; 20), which rollers (15; 19) roll on a track (16; 24) which is connected to the shaft (17) which is arranged in such a way that it runs between the two rollers (15; 19), is firmly connected, and is provided with elevations and depressions which are coordinated with one another in such a way that the rollers (15; 19) arranged on the swivel lever (13; 18) lie opposite one another are in contact with the web, and that furthermore a coupling rod (12) is articulated on each of the two end regions of the pivoting lever (13; 18) and is connected to the corresponding piston (7, 8, 9, 10). Piston machine according to claim 1, characterized in that the track runs in a hollow spherical shell (26), the center of which lies at the intersection of the pivot axis (14; 20) of the pivot lever (13; 18) with the axis of rotation of the shaft (17), and the surface the path is directed radially towards the center, and that the two rollers (15; 19) which roll on the path (16; 24) have the shape of a truncated cone, the apex of the cone defined by the truncated cone in the center lies. Piston machine according to claim 1 or 2, characterized in that the respective coupling rod (12) is fixedly connected to the corresponding piston (7, 8, 9, 10) and in the region in which it is articulated on the swivel lever (13; 18), is guided in a linear guide (30) which is aligned parallel to the cylinder axis. Piston machine according to claim 3, characterized in that the articulation between the pivot lever (13; 18) and coupling rod (12) is designed such that the articulation point in the pivot lever (13; 18) essentially against its pivot axis (14; 20) back and forth this is slidably mounted away. Piston machine according to one of claims 1 to 4, characterized in that the pivot lever (13; 18) is formed from a frame (31), between the two legs (32, 33) of which the shaft (17) runs, and the two legs ( 32, 33) are each equipped with a bearing pin (34), by which the pivot axis is formed, and the bearing pins (34) are each mounted in a bearing (35), which bearings (35) are each held in a bracket (36) are which tabs (36) are firmly connected to the housing (25). Piston machine according to claim 5, characterized in that the bearings (35) in the tabs (36) which are fixedly connected to the housing (25) are designed to be adjustable. Piston machine according to one of claims 1 to 6, characterized in that means are provided on the shaft for transmitting the rotational movement to further transmission elements. Valve device for opening and closing inlet and outlet openings (45) in a cylinder of a piston machine, in particular a piston machine according to one of claims 1 to 7, characterized in that for each inlet and outlet opening (45) around a pivot axis (46 ) pivotable lever (47) is provided, which pivot axis (46) is mounted in a stationary manner with respect to the cylinder, and to which pivotable lever (47) a sealing plate (50) is articulated, which covers the respective opening in the cylinder in the closed state. Valve device according to claim 8, characterized in that the sealing surface (52) formed by the sealing plate (50) is substantially flat and in the closed state rests on a corresponding surface (53) of the cylinder surface surrounding the respective opening. Valve device according to claim 11, characterized in that the sealing plate (50) with respect to the pivot axis (46) of the pivotable lever (47) is held so that the sealing surface (52) of the sealing plate (50) with respect to the surface surrounding the respective opening (53) automatically sets. Valve device according to one of Claims 8 to 10, characterized in that a counterweight (54) is attached to the sealing plate (50) and is arranged in such a way that when the sealing plate (50) opens and closes, it moves with respect to the pivoting lever (47 ) is essentially stationary. Valve device according to one of claims 8 to 11, characterized in that at least the sealing plate (50) is made of a ceramic material.

Images