EP2643552B1 - Rotary piston machine - Google Patents

Description

The present invention relates to a rotary piston machine, in particular a rotary engine, according to the preamble of claim 1.

The invention will be described below with reference to a rotary piston engine in which a substantially triangular rotary piston rotates on an eccentric shaft arranged in the motor housing. However, the invention is also applicable to a rotary piston engine with two, four or more piston corners and can generally also with rotary piston engines, which have a centric in the motor housing rotating piston, are used. Furthermore, the invention can also be used in rotary-piston machines with two, three or more juxtaposed rotary pistons.

The present invention is preferably used in motor vehicles and in connection with a power generator, which is particularly suitable for use as a so-called range extender in electrically powered vehicles.

In motor vehicles with electric drive and range extender, the internal combustion engine of the range extender is usually started and stopped while driving without immediate action of the driver, in particular depending on the state of charge of the battery of the electric drive. In contrast to motor vehicles with a pure engine drive, the internal combustion engine of the range extender in such vehicles is not continuously but only temporarily operated and usually has longer downtime.

When starting and stopping the internal combustion engine of the range extender, it is important that the eccentric shaft and with it the rotary piston have a defined rotational position so as to achieve a reliable start or an advantageous holding position. In addition, it may be desirable to detect the speed and, where appropriate, their fluctuations during operation of the internal combustion engine.

For these purposes, a donor wheel coupled to the eccentric shaft is usually provided, which has in its peripheral region a defined structure, for example in the form of teeth and tooth spaces, which can be sensed by a rotation of the donor wheel. In this way, information about the current rotational position and speed of the encoder wheel or the shaft can be obtained.

It is an object of the present invention to provide a rotary piston machine with a simplified structure.

This object is achieved by a rotary piston machine according to claim 1.

The rotary piston engine according to the invention, in particular rotary engine, has a shaft and a sensor wheel with a first structure, based on which by scanning by means of a pickup, the rotational speed and / or rotational position of the shaft can be determined, and is characterized in that the encoder wheel for generating a Imbalance has a non-rotationally symmetric mass distribution.

The detection of the rotational speed and the rotational position of the shaft of a motor assembly by means of a transmitter wheel is from the document WO2008 / 054582 known.

The invention is based on the idea to design for the determination of rotational position and / or speed of the shaft encoder wheel so that it has an imbalance that is sufficiently large to one or more commonly arranged on the shaft balancing weights, to compensate for Imbalance of the eccentric shaft serve, at least partially replace.

In this way, can be dispensed with an additional balance weight, which significantly simplifies the construction and production of the rotary piston machine according to the invention.

Under a non-rotationally symmetric mass distribution in the context of the invention is to be understood that the mass of the encoder wheel is not distributed rotationally symmetrical about the axis of rotation of the encoder wheel. The mass of the encoder wheel is in this case distributed so that only a rotation about the axis of rotation by an angle of 360 °, the encoder wheel maps to itself, which, however, is not the case with a rotation at any other angle.

Preferably, the encoder wheel comprises a Geberradscheibe on which the first structure is, wherein the Geberradscheibe has a non-rotationally symmetric mass distribution. The first structure is in this case in particular on the outer circumference of the encoder wheel and may have a substantially rotationally symmetric mass distribution. In this embodiment, the imbalance of the encoder wheel is essentially realized by the design of the Geberradscheibe, in which the majority of the mass of the encoder wheel, without this having an effect on the first structure and thus on the reliability in determining the speed and / or rotational position of the sender wheel has.

In a further embodiment of the invention, the Geberradscheibe at least a first sector, which has a higher moment of inertia than a corresponding to the first sector and this opposite second sector of the Geberradscheibe. In particular, the encoder wheel disk has a greater thickness and / or mass density in at least one region of the first sector than in the corresponding region of the second sector. In this case, it is preferable for the region of the first sector to extend in the direction of the circumference of the encoder wheel disk. By these measures, a non-rotationally symmetric mass distribution and the resulting imbalance can be realized in a simple and reliable manner, without the total mass of the encoder wheel is unnecessarily large.

It is also preferred to design the mass distribution of the encoder wheel in such a way that the unbalance resulting from a rotation of the encoder wheel reduces or compensates for an imbalance of the rotating shaft. In this embodiment, the encoder wheel can be on one or more additional balance weights that compensate for an imbalance of the shaft, in particular the eccentric shaft, usually be waived, which further simplifies the construction of the engine.

The first structure, by means of which by scanning the rotational position and / or rotational speed of the shaft or the encoder wheel can be determined, preferably has at least partially a periodic course. Thereby, the rotational position or speed of the shaft can be determined in a particularly simple manner.

In a further advantageous variant of the invention, the encoder wheel has a second structure, with which cooperate a starter device and thereby can set the encoder wheel in rotation. Preferably, the second structure has the form of a ring gear, a so-called starter ring, which can be set in rotation by a gear of the starter device, which may itself be part of the rotary piston engine according to the invention. The integration of the sprocket and sender wheel in just one component, which can be mounted on the eccentric shaft, the installation of the engine is simplified, otherwise both the sender wheel and the ring gear would have to be mounted in separate assembly steps. In addition, this simplifies the construction of the engine and increases its compactness.

It is preferred that the sender wheel including the first and / or second structure is made in one piece. As a result, both the production of the encoder wheel including the first and second structure and their mounting on the shaft are simplified.

In particular, the encoder wheel including the first and / or second structure is realized as a cast part, whereby a particularly simple and reliable realization of the non-rotationally symmetrical mass distribution or the ring gear is made possible.

In an alternative embodiment, the second structure can be manufactured as a separate part and pressed onto the sender wheel. In this case, the production-technical characteristics in the production of the sprocket in particular can be taken into account without compromising the simplicity and compactness of the structure of the sender wheel.

Preferably, the encoder wheel is rotatably connected to the shaft. The shaft is in particular an eccentric shaft. The inventively non-rotationally symmetric mass distribution in the encoder wheel is used here in a particularly advantageous manner by imbalances in the rotation of the eccentric shaft to simple and reliable Way compensated or at least reduced, whereby the otherwise necessary balancing weights can be saved

Advantageously, the rotary piston machine comprises a transducer for scanning the first structure of the encoder wheel and an evaluation device for deriving the rotational speed and / or the rotational position of the shaft attachment of the sampled first structure of the encoder wheel.

Fig. 1

einen schematischen Querschnitt durch einen Kreiskolbenmotor bei unterschiedlichen Kolbenstellungen;

Fig. 2

ein Beispiel für ein Geberrad zusammen mit Einrichtungen zur Ermittlung der Drehstellung und/oder Drehzahl und zur Steuerung des Motors;

Fig. 3

ein Beispiel für ein Geberrad mit integrierter Unwucht;

Fig. 4

das in Fig. 3 gezeigte Beispiel in Vorder- und Seitenansicht;

Fig. 5

ein weiteres Beispiel für ein Geberrad mit integrierter Unwucht;

Fig. 6

ein weiteres Beispiel für ein Geberrad mit integrierter Unwucht;

Fig. 7

ein Beispiel für ein Geberrad mit Starterkranz;

Fig. 8

ein Beispiel für ein Geberrad mit Starterkranz und integrierter Unwucht;

Fig. 9

ein Beispiel für ein Geberrad mit Starterkranz zusammen mit einer Startereinrichtung zum Antreiben des Geberrades.

Further advantages, features and possible applications of the present invention will become apparent from the following description in conjunction with the figures. Show it:

Fig. 1

a schematic cross section through a rotary engine at different piston positions;

Fig. 2

an example of a sender wheel together with means for determining the rotational position and / or speed and for controlling the motor;

Fig. 3

an example of a sender wheel with integrated imbalance;

Fig. 4

this in Fig. 3 Example shown in front and side view;

Fig. 5

another example of a sensor wheel with integrated imbalance;

Fig. 6

another example of a sensor wheel with integrated imbalance;

Fig. 7

an example of a donor wheel with starter ring;

Fig. 8

an example of a donor wheel with starter ring and integrated imbalance;

Fig. 9

an example of a starter ring with a starter ring for driving the encoder wheel.

Fig. 1 shows a cross section through a rotary engine at different piston positions. A rotary piston 11 in the form of a triangle composed of flattened circular arcs circumscribes on a control disk 12 of an eccentric shaft 13 arranged in a motor housing 10 and causes it to rotate. The position of the axis of rotation 14 of the eccentric shaft 13 is stationary.

At the eccentric shaft 13, in particular at the end face, a sender wheel is arranged, which for reasons of clarity in Fig. 1 is not shown and subsequently based on the in Fig. 2 shown example is explained in more detail.

Fig. 2 shows an example of a donor wheel 20 having in the region of its outer periphery a structure or pattern in the form of a plurality of teeth 21 and tooth gaps 22 of substantially identical width. In addition, the one shown here

Example of a donor wheel 20, a further tooth 23 provided with about three times the width. Depending on the application, it may be advantageous to choose the width of the teeth 21 and the width of the tooth gaps 22 differently. In addition, it is possible to provide a tooth gap instead of a tooth 23 with a different width from the other teeth 21, which has a deviating from the remaining tooth gaps 22 width.

By a rotation of the eccentric shaft 13 about the rotation axis 14 (see Fig. 1 ) is coupled with this rotatably coupled encoder disc 20 also in rotation, so that their teeth 21, 23 and tooth gaps 22 arranged near the circumference of the encoder wheel 20 pickup 25, which is formed for example as an optical or inductive sensor, and from This can be scanned.

The sensor signals obtained during the scanning of the individual teeth 21, 23 or tooth spaces 22 of the rotating encoder wheel 20 are fed to an evaluation device 26 where they are processed and / or evaluated in such a way that information about the current rotational position and / or rotational speed of the encoder wheel 20 is obtained.

For example, it is possible to deduce the sensor signals obtained when scanning the wider tooth 23 passing through the pickup 25 to a defined rotational position of the encoder wheel 20. By a simple counting of the subsequently passing and the pickup 25 passing and scanned teeth 21 and tooth gaps 22 then the current angular position of the encoder wheel 20 can be determined relative to the defined rotational position. In addition, can be determined by temporary or continuous counting of the transducer 25 passing teeth 21, 23 and / or tooth gaps 22, a speed of the rotating encoder disc 20 and possibly closed to speed fluctuations.

The information derived in the evaluation device 26 is fed to a control device 27, which can control or regulate the rotary piston machine in a predetermined manner.

Preferably, the control device 27 controls a generator 28 through which the eccentric shaft 13 and the rotary piston 11 running around it in a defined position; especially at the time of starting and / or after stopping the rotary piston machine, can be brought.

Fig. 3 shows an example of a sensor wheel 30, for which the embodiments in connection with the in Fig. 2 shown example of a sensor wheel 20 apply accordingly.

In an area of the encoder wheel 30, an additional mass 31 is provided, which generates an imbalance upon rotation of the encoder wheel 30 about the rotation axis 14. In the example shown, the mass 31 is arranged in a region of the encoder wheel 30, which runs on the outer edge of a circle segment 32 of the encoder wheel disk 33. Under the encoder wheel 33 here is the circular disk-shaped inner portion of the encoder wheel 30 without the arranged in its peripheral region teeth 21, 23 and tooth gaps 22 to understand.

The mass 31 is preferably an integral part of the encoder wheel 30, in particular the encoder wheel 33, and is manufactured with this in one piece, for example in the form of a single casting.

The described arrangement of the mass 31, a mass distribution is achieved, which is not rotationally symmetrical with respect to the axis of rotation 14 of the encoder wheel 30. The sector 32 of the Geberradscheibe 33 thereby has an inertial moment which is greater than the moment of inertia of a corresponding sector 32 ', which with respect to the rotation axis 14 of the sector 32 opposite, with the same sector surface.

Fig. 4 shows that in connection with Fig. 3 described encoder wheel 30 both in front view (left figure) and in a sectional view in side view (right figure), in which the encoder wheel 33, which are arranged on the periphery of the encoder wheel 33 wider tooth 23 and the additional mass 31 in the form of a projection recognizable.

Alternatively or in addition to the projection shown here, it is possible to realize the additional mass 31 in whole or in part by forming in a corresponding region in or on the encoder wheel disk 33 a material with a mass density which is greater than the mass density of the encoder wheel disk 33. is provided. In the example shown, this would mean that the projection in the region of the mass 31 would be smaller or might even be omitted.

The FIGS. 5 and 6 show alternatives to that in the Fig. 3 and 4 shown example of the encoder wheel 30, in which a non-rotationally symmetric mass distribution for generating an imbalance by an over a circular sector of the encoder wheel 33, preferably uniformly distributed additional mass 35 or provided in the edge region of the Geberradscheibe 33 additional mass elements 36 is realized.

In principle, the imbalance in the rotation of the encoder wheel 30 about the rotation axis 14 can be generated by a plurality of further embodiments. Decisive here is that the mass of the encoder wheel 30 is distributed around the axis of rotation 14 of the encoder wheel 30 so that only a rotation through an angle of 360 °, but not at a rotation about any other angle to the rotation axis 14, the encoder wheel 30 on depicting yourself.

Fig. 7 shows an example of a donor wheel 40 with teeth 21, 23 and tooth gaps 22, which compared to the in Fig. 2 donor wheel 20 shown additionally a sprocket 50, in which a starter device (not shown) engage and thereby the encoder wheel 40 and the eccentric shaft 13 coupled thereto (see Fig. 1 ) can set in rotation about the axis of rotation 14. Because of this functional relationship, the ring gear 50 is also referred to as a starter ring.

In principle, the function of the ring gear 50 can also be realized by a differently designed structure with which the starter device can cooperate, for example by one or more recesses or openings in the sender wheel 40, into which e.g. a circumferential pin can engage a corresponding starter device.

The encoder wheel 40 is preferably made in one piece with the ring gear 50, for example, by machining and / or forming a piece of metal or by casting a the gear wheel 40 and the ring gear 50 comprehensive casting.

Alternatively, it is also possible to manufacture the encoder wheel 40 and the ring gear 50 individually, preferably by the o.g. Manufacturing techniques, and then connect them together, in particular by pressing the ring gear 50 to the encoder wheel 40th

By the described integration of ring gear 50 and encoder wheel 40 in a component which on the eccentric shaft 13 (see Fig. 1 ) can be mounted, an assembly step, namely the attachment of an additional sprocket or encoder wheel on the eccentric shaft 13, saved in the production of the engine. In addition, this simplifies the construction of the engine and increases its compactness.

Fig. 8 shows an example of a sensor wheel, which in addition to the ring gear 50 has a mass 31 through which a non-rotationally symmetric mass distribution is realized to produce an imbalance.

In this example, the advantageous effects of the provided with a ring gear 50 encoder wheel 40 (see. Fig. 7 ) combined with the advantages of a sensor wheel 30 with integrated unbalance. For the possible embodiments of the encoder wheel 40 with respect to the mass distribution, the above statements apply in connection with the in the FIGS. 3 to 6 according to examples shown.

Fig. 9 shows a schematic side view of an example of a sensor wheel 40 with starter ring 50 together with a starter device for driving the encoder wheel 40th

The encoder wheel 40 provided with teeth 21, 23 and tooth gaps 22 is non-rotatably coupled to the eccentric shaft 13 of a rotary piston engine and additionally has a toothed rim 50, which is an integral part of the encoder wheel 40 or is subsequently attached to the encoder wheel 40, for example by pressing or welding.

Upon rotation of the encoder wheel 40, the teeth 21, 23 and tooth gaps 22 pass through a transducer 25, which in the already associated with Fig. 2 scans described manner, from which information regarding the rotational position and / or speed of the shaft can be derived.

The optionally provided mass 31 (see. Fig. 8 ) is realized in this example as located on the sprocket 50 projection, for which the statements in connection with the in the Figures 3 and 4 apply according to examples shown.

The projection may, as described in more detail above, together with the encoder wheel 40 and the ring gear 50 in one piece, e.g. as a casting.

Alternatively, it is also possible to provide the projection on the encoder wheel 40, in particular on the encoder wheel, and to carry out this in one piece. In this alternative, it may be necessary for the ring gear 50 to have a correspondingly shaped recess through which the projection located on the encoder wheel 40 can pass.

On a starter shaft 52 driven by an electric motor 53, there is a starter pinion 51, which can intervene in the direction of the ring gear 50 by displacing the starter shaft 52, possibly including the electric motor 53, and can rotate it together with the encoder wheel 40. Because of this principle of operation, the device composed of starter pinion 51, starter shaft 52 and electric motor 53 may also be referred to as an engagement starter.

Claims (16)

1. A rotary piston machine, especially a rotary engine, with a shaft (12, 13) and a shaft encoder (20, 30, 40) that comprises a first structure (21 - 23), based on which the rotational speed and/or the rotational position of the shaft (12, 13) can be determined by sampling by means of a transducer (25), characterized in that the shaft encoder (20, 30, 40) has a non-rotationally symmetrical mass distribution in order to produce an imbalance.
2. A rotary piston machine according to claim 1, wherein the shaft encoder (30) comprises an encoder disk (33), on which the first structure (21-23) is arranged, wherein the encoder disk (33) comprises a non-rotationally symmetrical mass distribution.
3. A rotary piston machine according to claim 2, wherein the first structure (21 - 23) is arranged on the outer circumference of the encoder disk (33).
4. A rotary piston machine according to claim 2 or 3, wherein the encoder disk (33) comprises at least one first sector (32) that comprises a higher moment of inertia than a second sector (32') of the encoder disk (33) that corresponds to the first sector and lies opposite thereof.
5. A rotary piston machine according to claim 4, wherein the encoder disk (33) comprises in at least one region (31) of the first sector (32) a greater thickness and/or mass density and in the corresponding region of the second sector (32').
6. A rotary piston machine according to claim 5, wherein the region (31) of the first sector (32) extends in the direction of the circumference of the encoder disk (33).
7. A rotary piston machine according to any one of the preceding claims, wherein the mass distribution of the shaft encoder (20, 30, 40) and the resulting imbalance is realized in such a way that it can reduce or counterbalance an imbalance of the shaft (12, 13).
8. A rotary piston machine according to any one of the preceding claims, wherein the shaft encoder (40) comprises a second structure (50) that can cooperate with a starter apparatus (51 - 53) and thereby set the shaft encoder (40) in rotation.
9. A rotary piston machine according to claim 8, wherein the second structure (50) of the shaft encoder comprises a ring gear that can be set in rotation by a gear wheel (51) of the starter apparatus (51 - 53).
10. A rotary piston machine according to claim 8 or 9 with a starter apparatus, which can engage into the second structure of the shaft encoder and thereby set this in rotation.
11. A rotary piston machine according to any one of the preceding claims, wherein the shaft encoder (20, 40, 40) including the first and/or second structure (21 - 23 resp. 50) is made in one piece.
12. A rotary piston machine according to any one of the preceding claims, wherein the shaft encoder (20, 30, 40) including the first and/or second structure (21 - 23 resp. 50) is a cast part.
13. A rotary piston machine according to any one of the claims 8 - 10, wherein the second structure (50) is pressed onto the shaft encoder (40)
14. A rotary piston machine according to any one of the preceding claims, wherein the shaft encoder (20, 30, 40) is connected with the shaft (12, 13) in a torque proof manner.
15. A rotary piston machine according to any one of the preceding claims, wherein the shaft (12, 13) is an eccentric shaft.
16. A rotary piston machine according to any one of the preceding claims with a transducer (25) for sampling of the first structure (21 - 23) of the shaft encoder (20, 30, 40) and an evaluation apparatus (26) for deriving the rotational speed and/or the rotational position of the shaft (12, 13) based on the sampled first structure (21 - 23) of the shaft encoder (20, 30, 40).

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