阅读说明：本技术 用于动力单元的毂-毂连接 (Hub-hub connection for a power unit ) 是由 弗兰克·奥柏里斯特 奥利弗·奥柏里斯特 于 2019-10-09 设计创作，主要内容包括：本发明涉及一种动力单元,特别是用于混合动力车辆的动力单元,所述动力单元具有往复式活塞发动机和具有至少一个可与所述往复式活塞发动机驱动连接的发电机(40),其中,所述往复式活塞发动机具有至少两个活塞(44)和两个通过连杆(31)与所述活塞(44)连接的、反向旋转的曲轴(22),所述活塞(44)在至少两个串联布置中的气缸(29)中被引导,所述曲轴(22)被机械地同相地耦联。所述往复式活塞发动机包括带有第一连接装置的毂-毂连接,所述第一连接装置连接第一毂和第二毂,其中,在所述第一毂和所述第二毂之间的角度位置在组装期间是能够无级调节的。所述毂-毂连接具有连接盘(10)形式的第二连接装置,所述连接盘具有支承面(12),所述第一毂和所述第二毂分别抵靠在所述支承面上。此外,所述第二连接装置具有基体,所述基体具有嵌入其中的硬质材料元件,特别是金刚石碎片,所述硬质材料元件被布置在所述支承面(12)中。此外,本发明涉及一种具有动力单元的车辆,特别是混合动力车辆。(The invention relates to a power unit, in particular for a hybrid vehicle, having a reciprocating piston engine and having at least one generator (40) which can be connected in a driving manner to the reciprocating piston engine, wherein the reciprocating piston engine has at least two pistons (44) and two counterrotating crankshafts (22) which are connected to the pistons (44) by means of connecting rods (31), the pistons (44) being guided in at least two cylinders (29) arranged in series, the crankshafts (22) being mechanically coupled in phase. The reciprocating piston engine comprises a hub-hub connection with first connecting means connecting a first hub and a second hub, wherein the angular position between the first hub and the second hub is steplessly adjustable during assembly. The hub-hub connection has a second connection device in the form of a connection plate (10) having a bearing surface (12) against which the first hub and the second hub respectively bear. The second connecting device also has a base body with hard material elements, in particular diamond chips, embedded therein, which are arranged in the bearing surface (12). The invention further relates to a vehicle, in particular a hybrid vehicle, having a power unit.)

1. A power unit, in particular for a hybrid vehicle, having a reciprocating piston engine and having at least one generator (40) which can be connected in a driving manner to the reciprocating piston engine, wherein the reciprocating piston engine has at least two pistons (44) and two counterrotating crankshafts (22) which are connected to the pistons (44) by means of connecting rods (31), the pistons (44) being guided in at least two cylinders (29) arranged in series, the crankshafts (22) being coupled mechanically in phase,

it is characterized in that the preparation method is characterized in that,

-the reciprocating piston engine has a hub-hub connection with first connecting means connecting a first hub and a second hub,

-the angular position between the first hub and the second hub is steplessly adjustable during assembly, and

-the hub-hub connection having a second connection device in the form of a connection disc (10) having a bearing surface (12) against which the first hub and the second hub each bear, and having a base body with hard material elements, in particular diamond chips, embedded therein, which hard material elements are arranged in the bearing surface (12).

2. The power unit as set forth in claim 1,

it is characterized in that the preparation method is characterized in that,

the first hub comprises a crankshaft (22) and the second hub comprises an output hub, in particular a toothed sprocket (21) or a pulley.

3. The power unit as claimed in claim 1 or 2,

it is characterized in that the preparation method is characterized in that,

the first connecting means comprise a screw (20) screwed together with the internal thread of the first hub or a hub nut screwed together with the external thread of the first hub.

4. The power unit as claimed in any one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the first connecting means, in particular the screw (20), extends through the second connecting means.

5. The power unit as claimed in any one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the first connecting means, in particular the screw (20), exert a pressure force acting in the longitudinal direction on the second connecting means.

6. The power unit as claimed in any one of claims 2 to 5,

it is characterized in that the preparation method is characterized in that,

the first connecting device, in particular the screw (20), is screwed to the output hub in such a way that the torque transmission is directed against the screwing direction of the first connecting device.

7. The power unit as claimed in any one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the first hub and the second hub form parallel end faces which abut against the bearing surface of the second connecting device.

8. The power unit as claimed in any one of claims 2 to 7,

it is characterized in that the preparation method is characterized in that,

the at least one generator (40) is connected to the output hub via a gear transmission or via a traction device.

9. The power unit as set forth in claim 8,

it is characterized in that the preparation method is characterized in that,

the traction device comprises a chain or a toothed belt.

10. The power unit as claimed in any one of claims 8 or 9,

it is characterized in that the preparation method is characterized in that,

a first traction device connects the first generator (40) with the first crankshaft (22), and a second traction device connects the second generator (40) with the second crankshaft (22).

11. The power unit as claimed in any one of claims 1 to 9, wherein the at least one generator (40) is rotatable co-directionally with the first crankshaft (47) and counter-directionally with the second crankshaft (48), and a balance shaft (49) rotatable co-directionally with the second crankshaft (48) and counter-directionally with the first crankshaft (47), wherein the generator (40) is in direct driving connection with the first crankshaft (47) via a first traction device (50) or a first gear transmission and the balance shaft (49) is in direct driving connection with the second crankshaft (48) via a second traction device (51), wherein the balance shaft (49) and/or the second crankshaft (48) carries a flywheel element (52).

12. Vehicle, in particular a hybrid vehicle, having a power unit according to one of the preceding claims.

Technical Field

The invention relates to a power unit, in particular for a hybrid vehicle, having a reciprocating piston engine and at least one generator which can be connected in a driving manner to the reciprocating piston engine, according to the preamble of claim 1. The invention further relates to a vehicle, in particular a hybrid vehicle, having a power unit according to the invention.

Background

Document WO2012/056275a1 discloses a machine combination comprising an internal combustion engine and a generator for charging a battery of a hybrid drive. Known internal combustion engines have two cylinder-piston units arranged parallel to one another, wherein the pistons in the cylinders are each in driving connection with a crankshaft via a connecting rod. The generator is driven by one of the crankshafts via a gear. For this purpose, spur gears may be provided which connect the two crankshafts to one another. One of these gears can be in driving connection, directly or via an intermediate gear, with a spur gear fixed on the rotor shaft of the generator.

It is known to establish a connection between the crankshaft and the gear transmission, for example via external or internal toothing of the crankshaft. Such connections are expensive. Meshing teeth generally imply high manufacturing costs and complex manufacturing processes. Additionally, rapid mechanical wear occurs under dynamic loading.

Alternatively, it is known from practice to establish a connection between the crankshaft and the gear wheel via a cone connection. The cone connection comprises, for example, a cone-clamping element or a cone-double clamping assembly. Due to the use of such space-consuming clamping elements, care must be taken that the gears to be connected have a sufficient wall thickness. Therefore, the gears have no flexible design.

Disclosure of Invention

The object of the invention is therefore to improve a drive unit of the type described above in such a way that a simple, cost-effective and safe connection is generally established between the crankshaft and the gear mechanism between the two hubs. The invention also aims to provide a vehicle with the power unit.

According to the invention, this object is achieved by a power unit having the features of claim 1 and a vehicle having the features of claim 12.

In particular, the object is achieved by a power unit, in particular for a hybrid vehicle, having a reciprocating piston engine and having at least one generator which can be drivingly connected to the reciprocating piston engine, wherein the reciprocating piston engine has at least two pistons and two counterrotating crankshafts which are connected to the pistons by connecting rods and which are guided in at least two cylinders arranged in series, the crankshafts being mechanically coupled in phase. The reciprocating piston engine comprises a hub-hub connection with first connecting means connecting a first hub and a second hub, wherein the angular position between the first hub and the second hub is steplessly adjustable during assembly. The hub-hub connection has a second connection means in the form of a connection disc having a bearing surface against which the first hub and the second hub respectively bear. Furthermore, the second connecting device has a base body with hard material elements, in particular diamond chips, embedded therein, which are arranged in the bearing surface.

In a preferred embodiment of the invention, the first hub comprises a crankshaft and the second hub comprises an output hub. The output hub may advantageously be formed by a toothed sprocket or a pulley.

It is generally contemplated that the first hub comprises a crankshaft and the second hub comprises a drive hub. The drive hub may be formed of a toothed sprocket or pulley similar to the output hub.

It is also generally conceivable that the first hub comprises a generator shaft. It should be noted that the invention is not limited to the mentioned components here. Alternatively, each component of a reciprocating piston engine, in particular a rotating component, may be equipped with a hub-to-hub connection according to the present invention. For example, a hub-to-hub connection may be formed between the camshaft and the toothed sprocket.

The hub-hub connection according to the invention has a first connection means. The first coupling means may comprise a screw screwed to the internal thread of the first hub. For example, the toothed sprocket wheel can be screwed onto the crankshaft and thus connected in a force-fitting connection.

Alternatively, the first connecting means may comprise a hub nut which is screwed onto the external thread of the first hub.

The use of screws as the first connection means of the hub-to-hub connection according to the invention is a simple form of connection, which facilitates repair and assembly and disassembly of the connection in the presence of damage. This consequently results in low manufacturing and assembly costs. By means of the threaded connection, for example, the toothing of the crankshaft can be omitted, which in turn reduces the production costs of the power unit.

The hub-hub connection according to the invention has a second connection means. The second coupling means is designed in the form of a coupling disc having a bearing surface against which the first hub and the second hub respectively abut. A space-saving friction-fit connection between the hubs can be achieved using the connecting discs. In this respect, the connecting disc is preferably designed for a friction-fit connection of the hub, in particular the crankshaft and the toothed sprocket wheel, with one another.

It is particularly advantageous if the connecting disk has a base body with hard material elements in order to increase the friction between the two components. In this case, parts that are clamped together can be used, which are preferably screwed together and connected to one another in a force-fitting manner. This may involve, for example, clamping between the toothed sprocket and the crankshaft. The connecting disk having a basic body with hard material elements embedded therein additionally increases the static friction between the threaded crankshaft and the toothed sprocket. Thereby providing a secure connection between the crankshaft and the toothed sprocket.

Ideally, the land has a matrix with diamond chips embedded therein. A micro form-fitting connection will thereby be produced. It has been shown that the coefficient of friction between the toothed sprocket and the crankshaft is increased by a factor of two to four. By increasing the coefficient of friction, the connecting disc according to the invention achieves an efficient torque transmission between the crankshaft and the toothed sprocket. This in turn ensures efficient engine control, particularly for hybrid vehicles, and thus low fuel consumption.

Another advantage of the hub-hub connection according to the invention is that the angular position between the first hub and the second hub can be adjusted steplessly during assembly. The infinitely definable adjustment of, for example, the crankshaft results in an improvement of the efficiency of the reciprocating engine. The starting process of the reciprocating piston engine and thus of the hybrid vehicle can also be accelerated considerably if the initial angular position of the crankshaft is steplessly adjustable, and the emission of harmful substances can therefore also be reduced. The simple design of the hub-to-hub connection facilitates adjustment not only between the angular position of the crankshaft and the toothed sprocket, but also between the crankshaft and the generator.

In a preferred embodiment, the first connecting means, in particular a screw, extends through the second connecting means. For example, the toothed sprocket may have a central screw for fixing to the crankshaft. The connecting disc may be mounted between the gear and the crankshaft. In this case, a screw for fixing extends centrally through the connection plate. The invention is not limited to a single screw. It is contemplated that the connecting disc has a plurality of openings so that a plurality of screws may extend through the connecting disc. Advantageously, the first connecting device, in particular the single first connecting device, extends centrally through the second connecting device. This ensures stable fixation.

In a preferred embodiment, the first connecting means, in particular a screw, exerts a pressure force acting in the longitudinal direction on the second connecting means. In this case, for example, a screw for fastening the toothed sprocket to the crankshaft can exert a pressure on the connecting disk between the toothed sprocket and the crankshaft. This additionally enhances the friction fit connection of the connection pads. Thus, there is a safe and stable connection between the toothed sprocket and the crankshaft.

Ideally, the first connecting device, in particular a screw, is screwed to the output hub in such a way that the torque transmission is directed against the screwing direction of the first connecting device. This prevents the screws from loosening during the commissioning of the reciprocating piston engine.

In a preferred embodiment of the invention, the first hub and the second hub form parallel end faces which bear against a bearing surface of the second connecting device. For example, the coated connecting disc may be disposed directly between the crankshaft and the toothed sprocket. The end face of the toothed sprocket is in this case oriented parallel to the end face of the crankshaft. The left side bearing surface and the right side bearing surface of the connecting disc are respectively in direct contact with the end surface of the toothed chain wheel and the end surface of the crankshaft.

The larger the bearing surface between the connecting disc and the crankshaft and toothed sprocket, the more effective the friction-fit connection between the components and the torque transmission between the toothed sprocket and the crankshaft. This also means that the connecting disk can advantageously have a base body with embedded hard material elements on both sides.

In a further preferred embodiment, the at least one generator can be connected to the crankshaft via a gear mechanism or via a traction mechanism. Ideally, this embodiment enables the power unit for the hybrid vehicle to operate with low noise.

The traction means may for example comprise a chain or a toothed belt. The first traction device advantageously connects the first generator with the first crankshaft and the second traction device connects the second generator with the second crankshaft. In this case, the traction means can be designed to be relatively short and thus space-saving.

In another preferred embodiment, a power unit may be provided that includes at least one generator rotatable in a same direction as the first crankshaft and in a reverse direction to the second crankshaft, and a balance shaft rotatable in a same direction as the second crankshaft and in a reverse direction to the first crankshaft. The generator is in this case directly in driving connection with the first crankshaft via the first traction means or the first gear mechanism, wherein the balancing shaft is directly in driving connection with the second crankshaft via the second traction means. The balance shaft and/or the second crankshaft carry a flywheel element.

The invention is based on the idea of replacing the second generator with a flywheel element on the balance shaft and/or the second crankshaft, as is provided, for example, in the prior art according to DE102014115042a 1. The smooth running that is also provided by the known power unit is achieved by the flywheel element. Thus, the power is not reduced with further impact on the advantages of the known power unit.

At the same time, the same components as in other previously known power units having higher power levels may be used. This results in a component system with which power units having different power levels can be produced at low cost. In particular, it is thus possible to keep the two-cylinder reciprocating piston engine, which is the basic module of the component system, the same for different power levels. Thereby significantly reducing costs in mass production.

Within the scope of the invention, a vehicle, in particular a hybrid vehicle, with a power unit according to the invention is also claimed.

Drawings

The invention is explained in more detail below with reference to the drawings. Shown in the attached drawings:

fig. 1 shows a perspective view of a coated connection pad according to an exemplary embodiment of the present invention according to claim 1;

FIG. 2 illustrates a partial cross-sectional view through a reciprocating piston engine for a power unit according to an exemplary embodiment of the present invention along a rotational axis of a crankshaft;

FIG. 3 illustrates a front cross-sectional view through a power unit according to an exemplary embodiment of the present invention;

FIG. 4 illustrates a power unit in which a flywheel element is carried by a balance shaft, according to an exemplary embodiment of the present invention; and

FIG. 5 illustrates a power unit in accordance with another exemplary embodiment of the present invention, wherein a flywheel element is carried by the second crankshaft.

Detailed Description

Fig. 1 shows a perspective view of a coated connecting disk 10 for a power unit according to the invention according to claim 1. The connecting disk 10 is designed to be annular and flat. It has right and left bearing surfaces 12. Centrally, a central opening 14 is provided, through which a screw 20 can extend through the connecting plate 10 in order to be fixed between the toothed sprocket 21 and the crankshaft 22.

In general, the connection pad 10 may have a coating 11. The coating 11 here enhances the friction-fit connection between the hub-hub connection according to the invention. In a preferred embodiment, the connecting disk 10 has a coating 11, which coating 11 has hard material elements embedded therein. The connecting disk 10 can be coated on the right-hand or left-hand bearing surface 12 or advantageously on both bearing surfaces 12. Ideally, the coating 11 has diamond chips. Thereby ensuring an increased friction fit connection. The coating 11 may partially or completely cover the connection pad 10. The layer thickness of the coating 11 can be greater than the thickness of the terminal pad 10. It is generally applicable that a thicker layer of the land 10 enables an increased friction fit connection.

Figure 2 shows a partial cross-sectional view through a reciprocating piston engine for use with a power unit according to an exemplary embodiment of the present invention. The cross-section extends through the cylinder 29 and through the axis of rotation of the crankshaft 22. The reciprocating piston engine has a crankcase 26. The crankshaft 22 is disposed in a lower portion of the crankcase 26. The crankshaft 22 may be surrounded by an oil collection zone 27 below the crankshaft 22.

The crankshaft 22 illustratively includes two crank arms 23. The crank pin 23a is mounted on the crank arm 23 on the left side. The crank arm 23 and the crank pin 23a on the left have holes in the middle for the screws 20. The toothed sprocket wheel 21 is fixed to the crank arm 23 in a rotationally fixed and force-fitting manner by means of the screw 20. The toothed sprocket 21 has a toothed hub 21a on the side facing the crankshaft 22. The hole extends horizontally through the crank arm 23 and the crank pin 23a, and passes through the toothed sprocket 21 and the toothed hub 21a in the middle. The screws 20 therefore project from the toothed sprocket 21 into the crank arms 23. The screw 20 is in this case located deep in the toothed sprocket 21.

The threads may extend through the crank arm 23 and crank pin 23 a. Furthermore, the thread can extend all the way into the toothed hub 21 a. The holes illustratively extend through almost the entire length of the crank arms 23. The screw diameter is here preferably approximately as large as the crank pin 23 a. In particular, the screw diameter may have a dimension corresponding to between 50% and 80% of the dimension of the crank pin diameter. This increases the stability of the hub-to-hub connection.

A screw 20 extends centrally through the connecting plate 10. In particular, the screw 20 and the connection disc 10 are arranged coaxially. Here, the axial pressure of the screw 20 acts on the connection plate 10. The connecting plate 10 has right and left bearing surfaces 12 against which the end surface 13a of the crank pin 23a and the end surface 13 of the sprocket hub 21a abut, respectively. The connecting disc 10 has the same diameter as the end face 13a of the crank pin 23a and the end face 13 of the toothed hub 21 a.

A plurality of crankshaft bearings 24, designed as rolling bearings 25, are arranged on the crankshaft 22. The rolling bearing 25 includes an inner ring 25a and an outer ring 25 b. A circular rolling body 25d is arranged centrally between the inner race 25a and the outer race 25 b. On the side of the crankshaft 22 facing the toothed hub 21a, a rolling bearing 25 is mounted, which is locked with a locking element 25 c. The locking element 25c is arranged between the rolling bearing 25 and the toothed sprocket 21.

The rolling bearing 25 circumferentially engages the sprocket hub 21a, the crank pin 23a and the connecting plate 10.

In this case, the outer peripheral surface of the land 10 abuts on the inner ring 25a of the rolling bearing 25.

A connecting rod bearing 30 is mounted on the crankshaft 22 between the crank arms 23. The connecting rod bearing 30 connects the crankshaft 22 with the connecting rod 31. The task of the crankshaft 22 in this case is to receive the force transmitted via the connecting rod 31 and to convert this force into a torque. This torque may then be further transferred to the generator 40.

The connecting rod 31 is connected to a piston 44, not shown, which can execute an oscillating movement in the cylinder 29 and thus exert a pressure on the fuel mixture present in the cylinder 29.

Figure 3 shows a front cross-sectional view through a power unit with a reciprocating piston engine according to the present invention. The reciprocating piston engine has two crankshafts 22 and two cylinders 29 in a series arrangement. In this case, the cylinders 29 are arranged in parallel with each other. On the crankshaft 22, toothed chain wheels 21 are arranged, which toothed chain wheels 21 mesh with one another and drive the crankshaft 22, which is coupled mechanically in phase, in a counter-rotating manner.

The connecting rods 31 are each connected in an articulated manner to a piston 44, which is each guided in one of the two parallel cylinders 29. The connecting rod 31 can perform an oscillating movement in the upward and downward direction.

Above the cylinder 29 are mounted inlet and outlet valves 45, 46, which are connected to the inlet and outlet ducts, respectively. These valves are typically operated by a camshaft via control levers and rocker arms during each firing stroke of the reciprocating piston engine.

The crankshaft 22 is connected to one of the two generators 40 via a not shown traction device, such as a chain, a toothed chain or a toothed belt, respectively. Above the two generators 40, accommodating chambers 41 for electronic equipment are respectively installed. Such a power unit with a reciprocating piston engine and two generators 40 can be advantageously used as a drive unit for a hybrid vehicle. The hub-hub connection according to the invention can be installed, for example, between a crankshaft and a toothed sprocket or between a generator and a gear connected to its drive.

In fig. 4 a power unit according to an exemplary embodiment of the present invention is shown, which is essentially formed by a reciprocating piston engine, a generator 40 and a balance shaft 49. The reciprocating piston engine has two cylinders 29 arranged in series, in particular parallel to each other. In the cylinder 29, a piston 44 is guided, which is coupled in an articulated manner to the crankshafts 47, 48 by a connecting rod 31. The crankshafts 47, 48 are rotatable in opposite directions and have gears 50, 51, respectively, on the end faces, which mesh with each other to synchronize the movement of the pistons 44. It is preferably provided that the distance between the articulated connections between the connecting rod 31 and the piston 44 is smaller than the distance between the crankshaft axes. The cylinders 29 are thus arranged offset inwardly with respect to the crankshafts 47, 48. This results in a slight angle between the connecting rod 31 and the crankshaft axis at the top dead center of the piston, whereby the piston skirt friction is reduced. This results in a particularly smooth engine start.

In the exemplary embodiment according to fig. 4, a flywheel element 52 is fixed on the balance shaft 49. In particular, the balance shaft 49 carries a flywheel element 52. The flywheel element 52 is connected to the balance shaft 49 in a rotationally fixed manner. In this embodiment of the power unit, gears or belt pulleys are mounted with the same diameter on the generator 40 and the balance shaft 49, said gears or belt pulleys being in engagement with the respective traction means 50, 51. This causes the generator 40 and the balance shaft 49 to rotate at the same rotational speed, so that the rotating mass of the generator 40 and the flywheel mass of the flywheel element 52 are balanced with each other. In this way, in particular the second moment of inertia is compensated.

In the exemplary embodiment according to fig. 5, the flywheel element 52 is arranged on the second crankshaft 48. In particular, the second crankshaft 48 carries a flywheel element 52. However, the flywheel element 52 is preferably coupled indirectly via a transmission with the second crankshaft 48, so that the flywheel element 52 rotates in operation at twice the speed relative to the second crankshaft 48.

List of reference numerals

10 connecting disc

11 coating layer

12 bearing surface

End face of 13-tooth chain hub

13a end face of crank pin

14 opening

20 screw

21-tooth chain wheel

21a tooth chain hub

22 crankshaft

23 crank arm

23a crank pin

24 crankshaft bearing

25 rolling bearing

25a inner ring

25b outer ring

25c locking element

25d rolling element

26 crankcase

27 oil collecting area

29 cylinder

30 connecting rod bearing

31 connecting rod

40 electric generator

41 housing chamber

44 piston

45 air inlet valve

46 exhaust valve

47 first crankshaft

48 second crankshaft

49 balance shaft

50 first traction device

51 second traction device

52 flywheel component