The object of the invention is to provide a compact drive unit with or for a propeller. A further object of the invention is to provide a propeller with a drive unit or propeller-drive units. Propellers or propeller drives of this type can be used for example in the case of missiles, in particular propeller-driven aeroplanes or drive pods for aircraft or watercraft of any type.
The drive unit should be accommodated in the propeller spinner and should utilize the otherwise unused space in an aerodynamically ideal manner, so that it is possible to dispense with bulky engine spaces in the body and a power transmission—possibly complicated—to the propeller. The seats for the pilot and additional persons should be provided immediately adjacent to the propeller. In addition, in view of the limited space available in the propeller spinner, the drive unit should be designed in a mechanically simple manner and should be capable of high performance, and the drive unit, in particular in the form of a drive pod for aircraft and watercraft, should permit an aerodynamically ideal shape.
In the case of a propeller or propeller drive in accordance with the type defined in the introduction, these objects are attained with the features set out in claim 1.
By means of the arrangement, according to the invention, of a gas turbine on a drive shaft situated in front of the propeller, i.e. in front in the propulsion direction, a smoothly running and compact high-performance drive unit is made possible.
In this case it is particularly advantageous for the features of claim 2 to be used in accordance with the power of the turbine. In the case of lower-powered turbines, it is structurally advantageous for the compressor stage to be arranged in front of the turbine. If higher performances are desired, a multiple-stage axial turbine with a compressor stage arranged to the rear contrary to the propulsion direction is used, these in turn being jointly arranged in front of the propeller in the propulsion direction.
The compressor stage can be at least one radial compressor stage, or an axial compressor stage or combined versions. The turbine can be a single- or multiple-stage radial or axial turbine or a combined version. It is provided in a space-saving manner that a radial compressor is provided as the compressor stage and an optionally multiple-stage radial turbine is provided as the turbine.
A particularly space-saving design is produced with the features of claim 3 when the turbine and the compressor stage are formed by a single component mounted on the drive shaft. The component has on one of its sides the compressor blades of the turbine stage and on its other side the turbine blades. In this way, very short structural lengths can be achieved, so that account is taken of the limited space in the propeller spinner. In addition, a component of this type does not project to an excessive degree radially, so that the said component can be accommodated in the forward end region of the propeller spinner in a satisfactory manner in terms of space.
The features of claim 4 are advantageous in a further advantageous utilization of the restricted availability of space in the propeller spinner. If the said structural elements are constructed in this arrangement, this increases the compactness of the drive unit and allows it to be accommodated in the propeller spinner in an advantageous manner. This compact arrangement is assisted by the features set out in claim 7. The radial extension of the individual structural elements provided can advantageously be selected in such a way that despite a high power output the internal contour of the propeller spinner is approximated and so the space is filled up tightly. The features of claims 5 and/or 11 are advantageous, since a very short design in the axial and longitudinal direction of the drive unit is made possible in this way.
For mounting purposes and for the assembly and the stable retention of the gear mechanism it is advantageous when the features of claim 6 are provided.
It is advantageous when the features of claims 12 and/or 13 are implemented. In the case of an arrangement of this type the bearings are situated as far as possible from the hot turbine or a suitable lubrication of the support shaft can take place at the same time as cooling of the oil in the oil cooler.
The features of claims 14 to 17 relate to advantageous arrangements which in turn contribute to the compact design and a transmission of the driving forces delivered by the turbine to the propeller with as little loss as possible.
The features of claim 19 are advantageous in the case of an axial turbine.
Advantageous embodiments of the invention are set out in the following description and in the drawings.
A drive shaft 6 with bearings 8 and 9 respectively at the ends is mounted on the second part 3′ [sic—recte 3″] in a rotatable manner. In its end region facing away from the propeller the drive shaft 6 carries a compressor stage 7 with radial or axial wheels or blades 87. A gas turbine 55 is arranged immediately following the compressor stage 7 in the direction of the propeller 23. The compressor stage 7 and the turbine 55 are advantageously constructed in the form of a one-piece component 86, i.e. the vanes 87 of the compressor stage 7 are formed on one side on a main component 6 and the blades or vanes 88 of the turbine 55 are situated on the axially opposite side.
In principle, a plurality of compressor stages or a plurality of turbines can be provided. The compressor stage and the turbine can be both radial or axial and combined units.
The combustion air supplied through a suction opening 5 in the propeller spinner 1 enters the compressor stage 7 through a central suction opening 56 and is introduced into a suction manifold 57 through the radially extending blades 87 of the compressor stage 7 and passes from there into a reverse combustion chamber 11. The said combustion chamber 11 is used for shortening the structural length of the drive unit. In the same way, a conventional combustion chamber could be provided, in which case the turbine 55 would have to be arranged at the end of the combustion chamber so as to be spatially separate from the compressor stage 7.
On grounds of space it may be advisable for the combustion chamber 11 to be constructed in the form of a reverse combustion chamber, the inlet of which is connected to the air outlet of the compressor stage 7 situated directly in front of the combustion chamber 11 in the longitudinal direction of the support shaft 3 and the outlet of which is connected to the inlet of the turbine 55 situated directly in front of the combustion chamber or surrounded by the combustion chamber 11 at least in part.
The forward part of the housing 65 of the combustion chamber 11 is used for receiving the air compressed by the compressor stage 7, so that the compressor stage 7 conveys directly into the combustion chamber 11, a reversal of air taking place in the region 57. The combustion gases, which flow out of the reverse combustion chamber 11, are likewise reversed radially by way of an outlet manifold 59 and encounter the vanes 88 of the turbine 55 in the radial direction. The outlet openings or the gas ducts are part of the combustion-chamber housing 65. The turbine 55 is bounded radially on the outside by the inner wall of the combustion-chamber housing 65, or a separate housing for the turbine 55 is not necessary if the turbine 55 is bounded by the inner wall of the combustion-chamber housing 65. The inner wall of the combustion-chamber housing 65 then leads the escaping exhaust-gas flows directly to the exhaust-gas diffuser 12.
Fuel is sprayed into the combustion chamber 11 by means of a fuel-injection device 58. The air supplied by the compressor stage 7 is introduced into the combustion chamber 11, in particular through openings 89 formed in the walls of the combustion chamber 11. The combustion gases passing out of the reverse combustion chamber 11 are supplied to the turbine 55 by way of the outlet manifold 59 in the radial direction and set the said turbine 55 in a corresponding rotation which the drive shaft 6 and the compressor stage 7 follow.
The gases passing out of the turbine 55 arrive in an exhaust-gas diffuser 12. The exhaust-gas diffuser 12 imparts a rotation to the gases and the jet of exhaust gas set in rotation in this way is removed, by way of an exhaust [duct] 13 adapted to the flow and preferably omega-shaped, to the outside. As shown in
The driving power is transmitted from the drive shaft 6 to a gear unit 14 in which a reduction gear 15 is preferably arranged. An oil cooler 16, an oil pump 17 and an oil filter 18 are carried by the gear mechanism 14, starting in a direction towards the propeller spinner 1. The mechanical drives for a fuel pump 19 and a fuel-control device 20 are provided in the centrally arranged apertures in the oil cooler.
The gear unit 14 steps down the rotational speed of the turbine 55 or the drive shaft 6 to the rotational speed of the propeller 23 and incorporates the oil pump 17, an oil tank 17′, an oil filter 18 and the oil cooler 16 in a very narrow design, as shown in greater detail in
The end of the drive shaft 6 towards the propeller is provided with a driving gearwheel 100 which meshes with a gearwheel 101 which carries a gearwheel 102. The gearwheel 102 meshes with a further gearwheel 103 which has a take-off gearwheel 104. The said take-off gearwheel 104 meshes with the take-off wheel 106 of the gear mechanism 105. The said take-off wheel 105 carries the propeller take-off flange 22 which is optionally mounted on a bearing 60 of the first part 3′ of the hollow shaft 3. The take-off wheel 105 meshes with the driving wheel 106 of the oil pump. In this way, a very flat gear mechanism is produced, which can also drive the oil pump or can also convey the fuel by way of further gearwheels or can drive a fuel pump. The said gearwheels are mounted in the gear-mechanism housing, which in turn is fastened on the hollow shaft 3 in a fixed manner in the region of the location of the join of the parts 3′ and 3″.
The driving moment is transmitted from the gear mechanism 14 by way of a gearing take-off flange 22 to the propeller 23 which can have an integrated jointly rotating blade-adjustment device 24. The blade-adjustment device 24 is actuated by way of adjustment means arranged on the drive-unit support 2 and actuable from the interior of the body 53. As shown in
The driving force necessary for starting or for generating current is transmitted by way of the propeller take-off flange 25 with a toothed-belt pulley 26 connected thereto. The belt drive 27 represents the mechanical link with the starter or to the generator 28.
The axial and radial fastening of the hollow shaft 3 on the drive-unit support is preferably carried out with clamping elements 29 and a toothing1 anti-twisting device 30 or with an axial Seeger circlip ring 31.
1N.B. The word Verzahlung was not found in any reference consulted, but on the basis of Internet searches appears to mean “co-operation” or “collaboration”, which makes little sense in this context. It has been assumed in the translation that it is a typographical error for Verzahnung meaning “toothing” etc.
The gear mechanism 14 is fastened or fixed on the hollow shaft 3. This fastening or fixing takes place in particular in the portion of the hollow shaft 3 in which the first part 3′ is connected to the second part 3″. This simplifies the mounting of the drive unit; first the mounting of the gear unit 14 on the first part 3′ takes place and then the fastening of the second part 3″ to the first part 3′, optionally accompanied by clamping the gear unit 14 on the first part 3′ in a fixed manner when the two parts 3′ and 3″ are joined.
It is clear from
As may be seen from
It is advantageous for the support shaft 3 to be constructed in the form of a hollow shaft, since in this case a supporting or actuating rod 63 for the displacement of the spinner 1, which can be adjusted in the longitudinal direction of the support shaft 3 by the said supporting or actuating rod 63, can be guided in the hollow shaft. The purpose of this is that, in the case where the propeller 23 is constructed in the form of a folding propeller, the propeller spinner 1 can be displaced forwards in order to form the gap for the propeller 23.
It is also advantageous for the compressor 7 and the turbine 55 to be arranged directly in the foremost region of the propeller spinner 1, since the air entering through a suction opening 5 formed in the spinner 1 can be drawn in this way directly into the suction opening 56 of the compressor housing.
It is also possible for the turbine housing or compressor housing and optionally the combustion-chamber housing 65 to be supported on the support shaft 3 in the end region of the latter remote from the propeller. In particular, a bearing 63 axially displaceable on the support shaft 3 can be provided for this case, in order to be able to compensate thermal expansion, in particular of the combustion-chamber housing 65.
The bearing 63 is illustrated only in outline in
The support of the housing 64 of the compressor stage 7 and the housing 65 of the combustion chamber 11 takes place primarily by way of the gear-mechanism housing and it does not affect the mounting of the revolving drive shaft 6 which rotates about the stationary support shaft 3.
The bearings 8 and 9 of the drive shaft 6 are arranged in the region of or on the axial ends of the drive shaft 6 in order to optimize the cooling. In order that at least the bearing 8 arranged on the side of the compressor stage should be lubricated to an adequate degree, an oil circuit with pump conveying is provided, which provides an adequate lubricating film of oil-spray.
The numeral 21 indicates an exit point or an outlet for control and supply lines out of the interior space of the first part 3′ of the hollow shaft 3, in order to be able to supply the drive unit with fuel or to control it.
As may be seen from
a shows a propeller, which is constructed in the form of a folding propeller, in its setting with the blades folded down. In this case the spinner 1 can be adjusted by the support and actuating rod 63 in such a way that the propeller spinner 1 rests against the body or adjoins the body directly without a gap. In
In the case of the drives according to the invention, it is possible for propellers capable of being pivoted in or propellers not capable of being pivoted in to be provided in the same manner. These may be rigid propellers or propellers adjustable with respect to their angle of incidence.
The compressor stage 7 situated between the turbine 55 and the gear-mechanism housing 14 comprises compressor vanes 87 which either rotate with the drive shaft 6 or, as in the present case, are formed in a stationary manner on the compressor housing 64 and/or on the combustion-chamber housing 65. The supply of combustion air takes place by way of an inlet 5 formed in the spinner 1. The air entering through the inlet 5 flows—as indicated by arrows—by way of the oil cooler 16 as a result of a suitable suction action into the compressor stage 7, in which case the air flowing in is led by way of baffle plates 111.
The fuel-injection units provided in the turbine housing or combustion-chamber housing 65 are not shown.
The compressor-stage housing 64 and the combustion-chamber housing 65 are supported in a bearing 63 on the support shaft 3. A lubricant circuit is formed in the gap between the drive shaft 6 and the support shaft 3.
The exhaust-gas duct or outlet for the combustion gases from the combustion-chamber housing 65 is not shown in
The annular combustion chamber arranged in front of the turbine 55 charges the combustion air supplied and this charged air is relaxed in the turbine stage and is removed by way of the outlet duct (not shown) situated in the forward region of the spinner.
The propeller 23 is driven in a comparable manner to what is illustrated in
In the case of the embodiment as shown in
1N.B. The syntax of the original German is uncertain. Omitted text or dittography might perhaps be involved.
Since the turbine 55 is arranged in front of the compressor 7, a satisfactory thermal separation from the propeller 23 is achieved.
In order to ensure the optimum thermal separation of the exhaust gas and the propeller 23, the gear mechanism 14 and the propeller unit 23 are arranged behind the compressor stage 7 contrary to the propulsion direction. This thermal separation takes place independently of the nature of the turbine used.
In the embodiment as shown in
In the case of the propeller drive unit as shown in
Number | Date | Country | Kind |
---|---|---|---|
102005043615.3 | Sep 2005 | DE | national |