WO2012069200A2

WO2012069200A2 - Rotary piston machine comprising a counterweight that is designed as a blower

Info

Publication number: WO2012069200A2
Application number: PCT/EP2011/005927
Authority: WO
Inventors: Michael Steinbauer; Andreas Krobath; Karl Knaus
Original assignee: Avl List Gmbh
Priority date: 2010-11-25
Filing date: 2011-11-24
Publication date: 2012-05-31
Also published as: AT510700A4; WO2012069200A3; AT510700B1

Abstract

The invention relates to a rotary piston machine, especially for use as a range extender combined with a generator in electric motor vehicles, which machine comprises at least one piston that co-rotates with an eccentric section of a drive shaft, a counterweight designed as a blower being arranged on the drive shaft.

Description

Rotary piston machine designed as a fan

counterweight

The present invention relates to a rotary piston machine and more particularly to a rotary engine.

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

An important requirement of such rotary piston machines is a space-saving, compact design. Due to the eccentric arrangement of the piston on the drive shaft results in an imbalance, which causes vibration or vibration, noise and wear of the drive elements and thus a shorter life of the components associated therewith. Such a so-called imbalance on the drive shaft can be avoided by attaching balancing weights.

The avoidance of imbalance takes place by balancing the mass distribution of the rotating body, which can be positive or negative. When positive compensation additional balancing weights are attached, z. B. by welding, gluing or screwing weights. In the case of negative compensation, masses are removed at suitable points of the rotating elements, for example by machining processes.

The object of the invention is to provide a compact design possible rotary piston machine available. This object is achieved by a device according to claim 1, to preferred developments of this device are the subject of the dependent claims.

To solve this problem, a rotary piston machine is proposed which has at least one piston rotating with an eccentric portion of a drive shaft and in which a balancing weight designed as a fan is arranged on the drive shaft.

Under a rotary piston machine according to the present invention, an internal combustion engine is to be understood in which chemically bound energy, preferably by an internal combustion due to an exothermic reaction, is converted into mechanical power by a so-called rotary piston during operation of the internal combustion engine in the housing in particular a Rotation about a major axis executes, the piston rotates on the one hand about its own axis, this axis but on the other hand also moves on its own circular path. The - -

Drive shaft of the rotary piston machine according to the invention preferably has an eccentric portion on which the piston or pistons of the internal combustion engine are mounted.

A special case of the rotary piston machine is a rotary piston machine in which a substantially triangular-shaped piston rotates on an eccentric shaft arranged in a motor housing. However, the invention is also applicable to a rotary engine with two, four or more piston corners and can generally be used in rotary piston engines or rotary piston engines with two, three or more juxtaposed pistons.

In this context, a balancing weight is to be understood as meaning a spatial mass arrangement on the drive shaft which is suitable for at least approximately compensating for an imbalance occurring in the absence of the balancing weight. An imbalance is generally referred to in rotating bodies whose mass is not rotationally symmetric distributed. In order to avoid oscillations or wear as a result, as far as possible, imbalances are balanced by counterweights.

In this context, a fan is to be understood as meaning a device which is suitable for causing an air movement when the drive shaft is rotating or for conveying another goose-shaped medium, preferably to generate an air flow. Fans are often referred to as fans or blowers. They preferably have at least one rotating impeller, in particular an axial impeller or a radial impeller. An impeller preferably consists of a ring of blades, also referred to as blades or rotor blades, which are held on the shaft via a suitable attachment.

Fans with axial impellers or radial impellers are referred to as axial fans or radial fans. In the axial fans, the axis of rotation of the axial impeller or axially to the air flow. The air is moved by the axial impeller, similar to an aircraft or ship propeller. Advantages of axial fans are the small dimensions in relation to the high air flow rate. For some designs, a lower pressure increase in relation to the centrifugal fan is to be accepted. Centrifugal fans are preferably used where, compared to axial fans on larger pressure increase with the same amount of air arrives. The air is sucked in parallel or axially to the drive axis of the centrifugal fan and deflected by the rotation of the radial impeller by 90 ° and blown radially.

According to a preferred embodiment of the invention, a rotary piston machine is provided in which the fan is an axial fan. An advantage of this embodiment of the invention is to see that the axial fan an axial so one for - -

Drive axis generates parallel air flow, which is particularly suitable to cool the rotary piston machine.

According to a preferred embodiment of the invention, a rotary piston machine is provided in which the fan is a radial fan or a cross-flow fan. One advantage of these embodiments of the invention is to be seen, can be represented by these types of fans a particular space-saving arrangement.

According to a further preferred embodiment of the invention, a rotary piston machine is provided, in which the balance weight is designed as a transmitter wheel. In this context, a sender wheel is an angular position sensor, that is to say a sensor in the general sense, which is suitable for generating a signal from which the angular position or a change in the angular position of the drive shaft can be deduced. A large number of different versions of such angular position sensors are known to the person skilled in the art whose even approximately representative representation would go beyond the scope of these statements. By way of example, only so-called incremental encoders and absolute encoders are mentioned here.

Incremental encoders are used for the digital relative detection of the angular position. Other common names for such incremental encoders are rotary encoders, incremental encoders or rotary encoders. Incremental encoders preferably have a periodic counting track, which is preferably arranged on a wheel-shaped object. The measurement is based on a direction determination and a count. Incremental encoders, for example, can be scanned photoelectrically, magnetically or in another way. In the photoelectric scanning can be distinguished between the so-called imaging measurement principle and the so-called interference measurement principle. The imaging measurement principle is suitable for graduation periods down to 20 microns, whereas the interferential measurement principle allows graduation periods as low as 4 microns. In the arrangement of the measuring tracks on sufficiently large radii very high angular accuracies can be achieved in this way.

In the imaging measuring principle, the scanning of the incremental encoder is carried out with the aid of a light beam, which is passed through the counting track on a photo-optical component, for example on a phototransistor. The counting track is in the simplest case a simple grating with different degrees of optical extinction. When the encoder wheel rotates, the light beam between the light source and the photo-optical component is periodically modulated, for example, in accordance with the design of the bar grating on the cell track. As an alternative to this transmitted light method, an incident light method is also occasionally used in which different reflections of the grating are used to modulate the light beam.

In the so-called interference measurement principle diffraction phenomena are used on a grid to generate a measurement signal. For this purpose, the light beam is - - Preferably passed through a condenser on a material measure, there reflected and returned by the condenser to the photoelectric sensors. The transparent scanning plate carrying a phase grating ensures that preferably three diffracted beam portions are generated. After the reflection at the also carrying a phase grating measuring scale, the scanning is again passed through the beams, wherein the zeroth diffraction order is canceled out by interference. Subsequently, the positive first and negative first diffraction order are imaged on three photoelements so that they generate a signal offset by 120 ° in each case. These three signals are then converted in a subsequent electronics in the industry-suitable two-signal form.

In the case of an incremental measuring system with magnetic scanning, the material measure consists of a preferably hard-magnetic carrier in which a division has been impressed by magnetization. The pitch period can be down to 5 mm in this system. The achievable angular resolution then results taking into account the radius of the carrier. The magnetic scanning is preferably used when encapsulation of the measuring system causes problems. It is largely insensitive to liquids and dirt as long as foreign objects do not enter the scanning gap. Another possibility is to scan a toothing made of non-magnetized ferromagnetic material, e.g. Iron by means of one or more DC applied induction coils. The fixed coils have a matching iron core for toothing. In the coils, an alternating voltage is induced during movement, which is evaluated according to polarity and phase angle.

Absolute encoders are angle encoders that output position information in the form of a digital numerical value that is unique over the entire resolution range of the absolute encoder. In such absolute value encoders, a preferably annular carrier has a preferably annular code ruler, which preferably consists of several parallel digitally encoded tracks, the different binary values being characterized by different extinction or reflection behavior or by other physical properties of the elements of the code -Lineals are determined. Such code rulers, like the cell tracks of incremental encoders, can be optically or magnetically scanned or otherwise scanned.

Angle encoders preferably have incremental, to be counted, or absolute material measures as a bar pattern, in the form of a magnetization or in the form of other, physically detectable quantities. In the case of a permanent magnetization, the magnetic field modulation can be evaluated by magnetic sensors, such as Hall sensors, AMR or GMR sensors or by inductive sensors. For incremental inductive sensors often also a non-magnetic toothing is sufficient.

According to a further preferred embodiment of the invention, a rotary piston machine is provided, in which the balance weight is used as an impeller with a multiplier. - - Number of arranged on the drive shaft blades is equipped. By a suitable arrangement of these blades or by a suitable distribution of the masses within these blades or between these blades, it is possible to achieve almost any required of the rotational symmetry mass distribution, in particular such a mass distribution, as for the construction of a balancing an imbalance appropriate balance weight is needed.

Such a balanced counterweight works at the same time as a fan and can work with suitable, preferably optical or magnetic scanning of the position of the blades, for example with the aid of magnetic or optical sensors additionally as a sender wheel. The blades themselves or on the blades or on a construction element of the balance weight attached to the vanes serve from tangible structures as material measures in the sense of the example described or other, familiar to those skilled embodiments of angular position sensors.

Preferably, at least one first blade of this balancing weight designed as a fan wheel has a mass that is different from the mass of at least one second blade. By a suitable choice of the blade masses and by a suitable arrangement of the blades with different masses in the impeller-like balance weight balancing of an existing on the drive shaft imbalance in this embodiment is possible only by an appropriate choice and arrangement of the blade masses, ie without further balancing weights.

A further preferred embodiment of the invention provides for a rotary piston machine in which at least one blade of a balancing weight designed as a fan wheel has an inhomogeneous mass distribution. By a suitable choice of the mass distribution of at least one blade a particularly effective balancing of imbalances on the drive shaft is possible, which helps to avoid unwanted weight increases the overall arrangement at the same time. Particularly advantageous are such mass distributions within a blade, in which the masses radially outward as possible, that is concentrated away from the center of the drive shaft, because relatively large effects can be achieved in the balancing of imbalances in this way even with relatively small overall masses.

According to a further preferred embodiment of the invention, a rotary piston machine is provided in which at least one first blade of a balancing weight designed as a fan has a shape that is different from the shape of at least one second blade.

Preferably, in this case, differences in the shape of the blades are designed so that in the intended speed range of the drive shaft through this - -

Differences aerodynamically generated non-axial torques are as small as possible. This has the advantage that non-axial torques of aerodynamic origin due to shape differences of the blades, which are regularly speed-dependent, can not lead to speed-dependent imbalances.

According to a further preferred embodiment of the invention, a rotary piston machine is provided, in which the balance weight has an approximately axially symmetrical wheel-shaped or annular component which is arranged concentrically to the drive shaft. Preferably, this is a so-called shroud, which connects the radially outwardly directed ends of the blades together and thus can stabilize mechanically. Such a shroud or a corresponding other approximately axially symmetrical wheel or annular component can preferably be provided with scannable structures that can be used as a material measure for a sensor wheel.

In a further preferred embodiment of the invention, a rotary piston machine is provided, in which the approximately axially symmetrical wheel or annular component of the balance weight has or carries a spatial or material structure which can act as an angle encoder. Preferably, these structures are serrated or toothed, preferably annular structures or oppositely magnetized areas of a magnetic coating or structures of materials having different optical reflection or extinction behaviors.

According to a further preferred embodiment of the invention, a rotary piston machine is provided, in which the structure acting as an angle encoder structure is provided for an optical scanning. With optical scanning very high angular resolutions can be achieved.

In a further preferred embodiment of the invention, a rotary piston machine is provided in which the structure acting as an angle encoder structure is provided for a magnetic scanning. Magnetic scans are particularly insensitive to optical interference from the environment.

Particularly preferred embodiments of the invention have in common that the balance weight is preferably designed and arranged on the drive shaft, that a large part of its mass is arranged at the greatest possible distance from the axis of rotation of the drive shaft. The mass can be made in one piece with a structural component of a fan impeller, preferably with the or some blades of the impeller. In another embodiment, the leveling compound can be connected to a structural component of a fan impeller by means of an integral connection such as, for example, a weld or gluing, a non-positive connection such as a screw connection or a positive connection such as riveting or a positive connection. be attached to the or some blades of the fan or integrated into it. In this case, the balance weight can be executed in one piece as well as in several parts. Also, the balance weight can be made of different materials, in multi-part balancing weights and sub-masses may consist of different materials.

The features of these and other embodiments of the invention may be combined with one another to form further embodiments of the invention.

In the following the invention will be described in more detail by means of preferred embodiments with the aid of figures. Showing:

Figure 1 shows schematically a first preferred embodiment of a balance weight according to the invention and

2 shows schematically a second preferred embodiment of a balance weight according to the invention.

The first embodiment shown in Figure 1 of a balance weight according to the invention has the shape of a fan or fan with impeller blades (103 and 104) which are mounted on a cylindrically symmetrical center body (105).

This cylindrically symmetrical central body (105) is mounted on the drive shaft (106) by means of a fastener (107) so that the balance weight (impeller or impeller) moves with the drive shaft (106). On a ring-shaped shroud (101) of the impeller, which connects the ends of the impeller blades together, a mass (102) is arranged, which breaks the otherwise symmetrical mass arrangement of the impeller, whereby the entire impeller assumes a non-rotationally symmetric mass distribution. With a suitable arrangement of this mass (102), the arrangement shown in Figure 1 acts as a balance weight for an imbalance on the drive shaft (106).

As an alternative to, or in addition to, the mass (102) mounted on the annular structure (101), the mass distributions of individual blades (103, 104) may be different, thereby resulting in a non-rotationally symmetric mass distribution, such as compensating for an imbalance on the drive shaft (106) is needed.

For example, the blade (103) may have a larger mass than any other blade, or the mass of individual blades may be concentrated in the vicinity of the coronal member (101). To produce a suitable balance weight to balance the imbalance on the drive shaft (106), these measures of individual impeller blades may be different than other impeller blades. - -

In addition, masses (102) may be disposed on the impeller. It is advantageous to arrange the non-rotationally symmetric masses radially as far as possible outside, and if possible also combined in a suitable manner. So it can be different, the mass of individual impeller blades or it can reach the mass distributions large balancing effect with the lowest possible mass use.

Also shown in Figure 2 second embodiment of a balance weight according to the invention has the shape of a fan or fan with impeller blades (203 and 204) which are attached to a cylindrically symmetrical center body (205).

This cylindrically symmetrical central body (205) is mounted on the drive shaft (206) by means of a fastener (207) so that the balance weight (impeller or impeller) moves with the drive shaft (206). On a ring-shaped shroud (201) of the impeller, which connects the ends of the impeller blades together, a mass (202) is arranged, which breaks the otherwise symmetrical mass arrangement of the impeller, whereby the entire impeller assumes a non-rotationally symmetric mass distribution. With a suitable arrangement of this mass (202), the arrangement shown in Figure 1 acts as a balance weight for an imbalance on the drive shaft (206).

The embodiment shown in Figure 2 of a balance weight according to the invention differs from the embodiment shown in Figure 1 by the arrangement of a coding track (208) on the center body (205). This coding track can be scanned by sensors mounted adjacent to this coding track, whereby a signal pattern corresponding to the coding track (208) is produced when the drive shaft (106) rotates.

Claims

claims

1. Rotationskoibenmaschine, in particular for use as a range extender in conjunction with a generator in electrically powered motor vehicles, which at least one with an eccentric portion of a

Drive shaft rotating piston has and

characterized in that

arranged as a fan balancing weight on the drive shaft (106, 206) is arranged.

2. Rotationskoibenmaschine according to claim 1, characterized in that the fan is an axial fan.

3. Rotationskoibenmaschine according to any one of the preceding claims, characterized in that

the balance weight is designed as a donor wheel.

4. Rotationskoibenmaschine according to any one of the preceding claims, characterized in that

the balance weight as an impeller with a plurality of on the drive shaft (106, 206) arranged blades (103, 203, 104, 204) is configured.

A rotary plate machine according to claim 4, characterized in that at least one first blade (103, 203) has a mass different from the mass of at least one second blade (104, 204).

6. Rotationskoibenmaschine according to any one of claims 4 or 5, characterized

marked that

at least one blade (103, 203, 104, 204) is an inhomogeneous one

Has mass distribution.

7. Rotary piston machine according to one of claims 4 to 6, characterized

marked that

at least one first blade (103, 203) has a shape that is different from the shape of at least one second blade (104, 204).

8. Rotary piston machine according to claim 7, characterized in that differences in the shape of the blades (103, 203, 104, 204) are designed so that in the proper speed range of

Drive shaft (106, 206) by these differences aerodynamically generated non-axial torques are as small as possible.

9. Rotary piston machine according to one of the preceding claims, characterized in that

the balance weight has an approximately axially symmetric wheel or annular component which is arranged concentrically to the drive shaft (106, 206).

10. Rotary piston machine according to claim 9, characterized in that the approximately axially symmetric wheel or rim-shaped component of the balance weight has or carries a spatial or material structure (208) which can act as an angle encoder.

11. Rotary piston machine according to claim 10, characterized in that the acting as an angle encoder structure (208) is provided for an optical scanning.

12. Rotary piston machine according to claim 10, characterized in that the angle sensor acting as a structure (208) is provided for a magnetic scanning.

13. Rotary piston machine according to claim 1, characterized in that the fan is a radial fan or a cross-flow fan.