DE102016217271A1 - Crankcase breather - Google Patents

Abstract

The invention relates to a crankcase ventilation device for an internal combustion engine (12) with a suction line (24), the blow-by gas from a crankcase (14) of the internal combustion engine (12) derived, with a Ölnebelabscheideeinrichtung (28) in the suction line (24 ), and a pumping device (26) for driving the blow-by gas disposed in the suction pipe (24). In order to improve the efficiency, it is proposed that the pumping device (26) is drive-coupled to the internal combustion engine (12) via a variable speed converter (30).

Description

The invention relates to a crankcase ventilation device for an internal combustion engine with a suction line, the blow-by gas derived from a crankcase of the internal combustion engine, with a Ölnebelabscheideeinrichtung disposed in the suction line, and with a pump device for driving the blow-by gas is arranged in the suction line. Furthermore, the invention relates to an internal combustion engine with such a crankcase ventilation device.

It is known to use pumping devices for crankcase ventilation devices in order to have a sufficient differential pressure for oil mist separation. This makes sense especially in supercharged internal combustion engines. There are various ways conceivable how the pumping device can be driven. For example, electrical, hydraulic or mechanical direct drives are possible by the internal combustion engine itself. The best efficiency would be achieved by a direct mechanical drive via the internal combustion engine. However, then the pumping device can not be set operating point dependent on the expected or occurring blow-by gas volume flows. As a result, the system usually has to be designed in such a direct drive in such a way that the pumping device in any case provides sufficient pumping power. As a result, in pump operation, for example in the partial load range, in which less blow-by gas is generated, unnecessary pump power is applied and thus energy is wasted.

For example, is from the DE 101 53 120 A1 Such a crankcase ventilation device is known, in which the pumping device is driven directly by the internal combustion engine. The pressure control in the crankcase is effected by pressure control valves, which thus lead to a loss of power.

The present invention has for its object to provide an improved or at least other embodiment of a crankcase ventilation device or an internal combustion engine with such a crankcase ventilation device, which is characterized in particular by a better efficiency.

The invention is based on the general idea that the pumping device is drive-coupled to the internal combustion engine via a variable speed converter. As a result, the rotational speed of the pump device can be set at least independently of the rotational speed of the internal combustion engine. As a result, the power of the pumping device can be reduced to operating pumps which have a low blow-by gas volume flow than the maximum blow-by gas flow. The amount of blow-by gas depends on the one hand on the speed of the internal combustion engine, on the other hand by the torque generated by the internal combustion engine. The performance map of the pumping device is usually also such that with increasing speed, an increased volume flow can be pumped out. Thus, the speed dependence of the occurring blow-by gas volume flow compensated by the speed dependence of the pump power of the pumping device. Only the torque dependence of the blow-by gas volume flow must be taken into account. If the maximum torque is not generated by the internal combustion engine, the speed of rotation of the pump device can be reduced by the variable speed converter, so that there is an adapted pumping power.

A favorable possibility provides that the variable speed converter has a hydraulic clutch. Such hydraulic clutches are known and proven in the automotive sector. Typically, most motor vehicles have a hydraulic system that can be used to control the hydraulic clutch. With a hydraulic clutch can be quickly and easily reduced the speed of the pumping device relative to the speed of the internal combustion engine.

Another favorable possibility provides that the speed converter has a transmission which has a ratio which is designed such that the pumping device, with the hydraulic clutch closed, at least pumps off a volume flow which occurs at full load on blow-by gas. This results in a design of the crankcase ventilation device, in which, when the hydraulic clutch is closed, in any case, the entire resulting blow-by gas volume flow can be pumped out. To adapt to other operating points, in which less blow-by gas volume flow obtained, the pump power can be adapted to the given blow-by gas volume flow by opening the hydraulic clutch and the consequent reduction of the speed of the pump device. Thus, a more efficient operation can be achieved.

Although occur through the speed reduction by means of the hydraulic clutch losses in the clutch. However, the losses are less than the losses that would occur in the pumping device due to the excessive pumping power.

An advantageous solution provides that the variable speed converter is formed by a hydraulic clutch. So can an additional Transmission between the pumping device and the internal combustion engine are omitted. As a result, the losses occurring in the transmission can be avoided.

A further advantageous solution provides that the hydraulic clutch has a first shaft and a wide shaft, that the hydraulic clutch has a working space in which first fins, which are coupled to the first shaft and second fins, which are coupled to the second shaft are arranged, and that for controlling and / or regulating the transmitting torque between the first shaft and the second shaft, a working fluid can be introduced and discharged into the working space. Thereby, by controlling the flow of the working fluid, a transmitted torque between the first and the second shaft can be achieved. At the same time, this embodiment allows a slip between the first and the second shaft, so that depending on the filling amount of working fluid in the working space, a speed reduction between the first shaft and the second shaft can be achieved. Therefore, such a hydraulic clutch can be used very favorably for the present crankcase ventilation device.

A particularly advantageous solution provides that the variable speed converter has a transmission with a variable transmission ratio. As a result, the variable speed ratio of the pump device can be optimally adjusted to the respective operating point or the resulting amount of blow-by gas at this operating point.

A favorable variant provides that the variable speed converter has a friction ring gear, in which between two conical wheels, a friction ring, which transmits a torque between the two conical wheels by friction. By shifting the friction ring in a gap extending between the two conical wheels, thus, a transmission ratio between the two conical wheels can be adjusted.

A further favorable variant provides that the variable speed converter has a belt transmission, in which two conical wheels are arranged against each other on the drive side and driven side, between which a belt or a chain is guided and which are adjustable in the axial direction, so that in each case an axial Adjusting the distance between the drive-side conical wheels and between the output-side conical wheels, so that a radial distance of the belt or the chain can be adjusted to the respective axis of the conical wheels. Due to the adjustability of the radial distances to the axes and the transmission ratio between the drive-side and output side cone wheels can be adjusted.

An advantageous possibility provides that the variable speed converter has a Torusgetriebe that the Torusgetriebe having a first Torusrad and a second Torusrad that the first and the second Torusrad each having a friction surface, which form at least a portion of a Torusfläche that the first Torusrad and the second torus gear are arranged coaxially with each other and the respective friction surfaces face each other, that the torus gear has at least one transmission gear abutting against the friction surface of the first torus gear and the friction surface of the second torus gear, and an axis of rotation of the transmission wheel is inclinable. Due to the inclination of the axis of rotation of the transmission wheel, the contact points of the transmission wheel move on the two toroidal gears. This also shifts a radial distance to the axis of rotation of the two torus wheels, so that a transmission ratio between the two torus wheels can be adjusted.

A particularly advantageous possibility provides that the pumping device is coupled to a crankshaft, a camshaft or a balancer shaft of the internal combustion engine. These shafts rotate at speeds that are proportional to the speed of the engine. Thus, these waves provide a favorable coupling possibility for the pumping device.

Further, the invention is based on the general idea of equipping an internal combustion engine with a crankcase ventilation device as described above, wherein the suction line of the crankcase ventilation device directs the blow-by gases from the crankcase to an intake tract of the internal combustion engine.

Other important features and advantages of the invention will become apparent from the dependent claims, from the drawings and from the associated figure description with reference to the drawings.

It is understood that the features mentioned above and those yet to be explained below can be used not only in the particular combination given, but also in other combinations or in isolation, without departing from the scope of the present invention.

Preferred embodiments of the invention are illustrated in the drawings and will be explained in more detail in the following description, wherein like reference numerals to the same or refer to similar or functionally identical components.

It show, each schematically

1 a schematic representation of an internal combustion engine with a crankcase ventilation device,

2 a sectional view through a viscous coupling,

3 a diagram of the power consumption of a pump device and the viscous coupling,

4 a schematic diagram of an internal combustion engine according to a second embodiment,

5 a sectional view through a variable friction-ring,

6 a perspective view of a variable belt transmission,

7 a schematic diagram of a variable torque transmission in a first position,

8th a schematic diagram of the Torusgetriebes 7 in a second position, and

9 a schematic diagram of the Torusgetriebes 7 in a third position.

One in the 1 to 3 illustrated first embodiment of a crankcase ventilation device 10 for an internal combustion engine 12 Used to blow-by gas from a crankcase 14 the internal combustion engine 12 derive. The internal combustion engine 12 preferably has a charging device 16 , in particular a turbocharger with a turbine 18 and a compressor 20 on. The compressor 20 is in an intake tract 22 the internal combustion engine 12 arranged and compressed fresh air to the internal combustion engine 12 charge.

To get the blow-by gases out of the crankcase 14 derive, the crankcase ventilation device 10 a suction line 24 on which of the crankcase 14 up to the intake tract 22 runs. The suction line 24 directs blow-by gases out of the crankcase 14 in the intake tract 22 ,

In the suction line 24 is a pumping device 26 arranged to drive the blow-by gases. The pumping device 26 For example, it may be a centrifugal compressor or a side channel compressor. Other pumping devices 26 are also possible.

Furthermore, in the suction line 24 an oil mist separator 28 formed, the oil mist, which is carried in the blow-by gas, separates from the blow-by gas, so that the blow-by gas safely the intake tract 22 can be supplied. The oil mist separator 28 works preferably inertia-based. For example, the Ölnebelabscheideeinrichtung 28 be designed as an impactor or cyclone.

The pumping device 26 is intended for a supercharged internal combustion engine 12 a sufficiently high differential pressure for the oil mist separation in the Ölnebelabscheideeinrichtung 28 to provide. To a low-loss drive of the pumping device 26 to enable is the pumping device 26 with the internal combustion engine 12 drive-coupled. The pumping device is according to the invention via a variable speed converter 30 with the internal combustion engine 12 drive-coupled. The coupling can be at different rotating parts of the internal combustion engine 12 , For example, the crankshaft, a camshaft or a balancer shaft.

The variable speed converter 30 has a gearbox 32 and a hydraulic clutch 34 on. The gear 32 may be formed, for example, as a belt or gear transmission or a mixture thereof. The gear 32 has a ratio, which is the speed of the internal combustion engine 12 in a certain ratio to the pumping device 26 passes.

Furthermore, the variable speed converter 30 a hydraulic clutch 34 on, which allows a slip. That is, the pumping device actually rotates slower than through the transmission 32 driven.

This allows the speed of the pump device 26 be reduced to unnecessarily high losses in the pumping device 26 to prevent. For this purpose, first, the translation of the transmission to the internal combustion engine 12 and the pumping device 26 adapted, that even in the worst case, the accumulating amount of blow-by gas through the pumping device 26 can be sucked off. The design is carried out, for example, such that at the operating point at which the internal combustion engine 12 generates the largest blow-by gas volume flow, namely at the maximum speed and the maximum torque, the pumping device 26 having a speed at which the pumping device 26 can dissipate this volume flow.

For cases in which due to a lower torque less blow-by gas is generated, with the help of the hydraulic clutch 34 the speed of the pumping device 26 reduced be to the pumping power of the pumping device 26 to throttle and thus save energy.

In the hydraulic clutch 34 although there are also losses. However, these are lower than the losses caused by the higher speed of the pumping device 26 would occur. The power consumption of the pumping device 26 increases with the cube of the speed, while the losses in the hydraulic clutch 34 only increase linearly with the speed.

In 3 By way of example, a diagram illustrating the power losses 36 in the pumping device 26 without the use of a hydraulic clutch 34 with the power losses 39 , which together in the pumping device 26 and the hydraulic clutch 34 but occur at a reduced speed.

Through the hydraulic coupling 34 becomes the pumping device 26 at a reduced speed 38 facing one from the gearbox 32 predetermined speed 37 is reduced, operated. At the hydraulic clutch 34 So is a differential speed from the reduced speed 38 and by the gear 32 predetermined speed, which leads to a loss of power. Since this increases linearly with the differential speed, this is less than the power loss in the pumping device 26 would have incurred. The difference is with the reference number 40 shown.

As exemplified in 2 is shown, the hydraulic coupling 34 a first wave 42 on, and first slats 44 , which are non-rotatable to the first shaft 42 are coupled. Preferably, the first fins 44 at the first wave 42 held. Furthermore, the hydraulic clutch 34 a second wave 46 on and second fins 48 , which is non-rotatable with the second shaft 46 are coupled. Preferably, the second fins 48 at one of a working space 52 enclosing bell 50 held against rotation, which in turn rotationally fixed to the second shaft 46 is attached. The first wave 42 extends into the work space 52 so that the first slats 44 and the second fins 48 in the workroom 52 can lie adjacent to each other and rotate. By introducing a working fluid, for example hydraulic oil, a torque transmission between the first lamellae caused by the viscosity of the hydraulic oil can occur 44 and the second fins 48 be achieved. This allows a torque transmission between the first shaft 42 and the second wave 46 be achieved. By adjusting the filling amount of the working fluid in the working space 52 the hydraulic clutch 34 Thus, the transmitted torque can be adjusted. As a result, in turn, a differential speed between the first shaft 42 and the second wave 46 be achieved.

By using this hydraulic clutch 34 in the speed converter 30 Can the gearbox 32 and the internal combustion engine 12 specified speed 37 be reduced. Thus, the pumping device 26 at a reduced speed 38 be driven according to demand.

An in 4 illustrated first embodiment of the crankcase ventilation device 10 is different from the one in the 1 to 3 shown first embodiment of the crankcase ventilation device 10 in that no gear 32 is provided. The adaptation of the pump power to the occurring blow-by gas volume flow, for example, by the dimensioning of the pumping device 26 be achieved. The reduction of the speed of the pumping device 26 takes place according to the crankcase ventilation device 10 according to the first embodiment, by the hydraulic clutch 34 ,

Incidentally, the in 4 illustrated second embodiment of the crankcase ventilation device 10 with the in the 1 to 3 shown first embodiment of the crankcase ventilation device 10 with regard to structure and function, to the above description of which reference is made.

An in 5 illustrated third embodiment of a crankcase ventilation device 10 is different from the one in 4 illustrated second embodiment of the crankcase ventilation device 10 in that the speed converter 30 through a transmission 53 is formed with variable transmission ratio. This allows for a hydraulic clutch 34 to reduce the speed.

The gear 53 With variable transmission ratio can in a first variant of the third embodiment of the crankcase ventilation device 10 , such as in 5 is represented by a friction ring gear 54 be formed. The friction ring gear has two cone wheels 56 on, which are arranged side by side, leaving a gap 58 between the two cone wheels 56 is formed. In the gap 58 runs a friction ring 60 , on the two cone wheels 56 rests and thus via frictional torque between the two conical wheels 56 can transfer. Depending on the position of the friction ring 60 in the gap 58 In each case, the radial distance to the axes of the respective conical wheels varies 56 , Therefore, by moving the friction ring 60 in the gap 58 a gear ratio between the two cone wheels 56 be set.

In a second variant of the third embodiment of the crankcase ventilation device 10 that exemplifies in 6 is shown, is the transmission 53 with variable transmission ratio through a belt drive 62 educated. The belt drive 62 has two drive wheels on the drive side and output side 64 on. These cone wheels 64 have a cone-shaped friction surface 66 on. The drive-side cone wheels 64 and the output side cone wheels 64 are each arranged coaxially with each other so that the friction surfaces 66 facing each other. Between the cone wheels 64 is both the drive side and the output side, a friction ring or a chain 68 guided. The radial position to the respective axis of the conical wheels 64 results from the distance between the conical wheels 64 and the width of the friction ring or the chain 68 , If these are far apart, the friction ring or the chain can 68 closer to the axis. Lie the cone wheels 64 closer together, becomes the friction ring or the chain 68 pushed outward.

Now become the drive side and the output side cone wheels 64 shifted simultaneously and complementary to each other, thus a ratio between the drive-side conical wheels 64 and the output side cone wheels 64 be set.

One in the 7 to 9 illustrated third variant of the third embodiment of the crankcase ventilation device 10 uses a torus gear 70 as a transmission 53 with variable transmission ratio. The torus gear 70 has a first torus wheel 72 and a second torus wheel 74 on, each one a friction surface 76 have, which form at least a portion of a Torusfläche. The first torus wheel 72 and the second torus wheel 74 are arranged coaxially with each other, so that the two friction surfaces 76 facing each other. The two toroidal friction surfaces 76 are preferably spaced apart such that they each form a portion of the same Torusfläche. As a result, the friction surfaces in a projection perpendicular to the axes of the torus wheels 72 . 74 two partial circular arcs.

The torus gear 70 has at least one, preferably two transmission wheels 78 on that around an axis of rotation 80 are rotatably mounted. The rotation axis 80 and thus the transmission wheel 78 are about a pivot axis 82 pivotable. The transmission wheels 78 are now arranged so that they both on the first torus 72 as well as on the second torus wheel 74 issue. The pivot axes 82 the transmission wheels 78 are preferably in the centers of the circles that belong to the two partial arcs that are projected through the toroidal friction surfaces 76 the torus wheels 72 and 74 are formed. This can be achieved by tilting the transmission wheels 78 around the pivot axis 82 be achieved that the transmission wheel along the friction surfaces 76 the torus wheels 72 . 74 moves and thus at different radial positions on the torus wheels 72 and 74 can be present.

In a first position, exemplified in 7 is shown, the transmission wheels 78 to the first torus wheel 72 turned back. This causes the transmission wheels 78 at the first torus wheel 72 radially further out than at the second torus wheel 74 , As a result, the first torus wheel rotates in the third position 72 slower than the second torus wheel 74 ,

At an in 8th shown second position are the transmission wheels 78 at the same radial positions on the torus wheels 72 and 74 at. This gives a 1: 1 translation, so that the first torus wheel 72 the same speed as the second torus wheel 74 ,

At an in 9 shown third position are the transmission wheels 78 to the second torus wheel 74 turned back. This causes the transmission wheels 78 at the first torus wheel 72 radially further inward than at the second torus wheel 74 , As a result, the first torus wheel rotates in the third position 72 faster than the second torus wheel 74 ,

Incidentally, the right in the 5 to 9 illustrated third embodiment of the crankcase ventilation device 10 with the in 4 illustrated second embodiment of the crankcase ventilation device 10 with regard to structure and function, to the above description of which reference is made.

A non-illustrated fourth embodiment of the crankcase ventilation device 10 is different from the one in the 5 to 9 illustrated third embodiment of the crankcase ventilation device 10 in that in addition to the transmission 53 with variable gear ratio a hydraulic clutch 34 is provided, as for example, from the first embodiment and from 2 is known.

Incidentally, the fourth embodiment of the crankcase ventilation device is correct 10 with the in the 5 to 9 illustrated third embodiment of the crankcase ventilation device 10 with regard to structure and function, to the above description of which reference is made.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 10153120 A1 [0003]

Claims (11)

Crankcase ventilation device for an internal combustion engine ( 12 ) with a suction line ( 24 ), the blow-by gas from a crankcase ( 14 ) of the internal combustion engine ( 12 ), with an oil mist separator ( 28 ) in the suction line ( 24 ) is arranged, and with a pumping device ( 26 ) for driving the blow-by gas in the suction line ( 24 ), characterized in that the pumping device ( 26 ) via a variable speed converter ( 30 ) with the internal combustion engine ( 12 ) is drive-coupled. Crankcase ventilation device according to claim 1, characterized in that the variable speed converter ( 30 ) a hydraulic clutch ( 34 ) having. Crankcase ventilation device according to claim 2, characterized in that the speed converter ( 30 ) a gearbox ( 32 ), which has a translation which is designed such that the pump device ( 26 ) with closed hydraulic clutch ( 34 ) evacuates at least one volume flow, which is produced at full load to blow-by gas. Crankcase ventilation device according to claim 1, characterized in that the variable speed converter ( 30 ) by a variable hydraulic coupling ( 34 ) is formed. Crankcase ventilation device according to one of claims 2 to 4, characterized in that - the hydraulic coupling ( 34 ) a first wave ( 42 ) and a second wave ( 46 ), - that the hydraulic coupling ( 34 ) a work space ( 52 ), in which first lamellae ( 44 ), with the first wave ( 42 ), and second fins ( 48 ), with the second wave ( 46 ) are arranged, and - that for controlling and / or regulating the transmitted torque between the first shaft ( 42 ) and the second wave ( 46 ) a working fluid into the working space ( 52 ) can be introduced and discharged. Crankcase ventilation device according to one of claims 1 to 3 and 5, characterized in that the variable speed converter ( 30 ) a gearbox ( 53 ) having a variable transmission ratio. Crankcase ventilation device according to one of claims 1 to 3 and 5 and 6, characterized in that the variable speed converter ( 30 ) a friction ring gear ( 54 ), in which between two conical wheels ( 56 ) a friction ring ( 60 ), which by friction torque between the two conical wheels ( 56 ) transmits. Crankcase ventilation device according to one of claims 1 to 3 and 5 to 7, characterized in that the variable speed converter ( 30 ) a belt drive ( 62 ), in which the drive side and the output side each two cone wheels ( 64 ) are arranged against each other, between which a belt ( 68 ) or a chain ( 68 ) is guided and which are adjustable in the axial direction, so that in each case the distance between the drive-side conical wheels ( 64 ) and between the output side conical wheels ( 64 ) so that a radial distance of the belt ( 68 ) or the chain ( 68 ) to the respective axis of the conical wheels ( 64 ). Crankcase ventilation device according to one of claims 1 to 3 and 5 to 8, characterized in that - the variable speed converter ( 30 ) a torus transmission ( 70 ), - that the Torusgetriebe ( 70 ) a first torus wheel ( 72 ) and a second torus wheel ( 74 ), - that the first torus wheel ( 71 ) and the second torus wheel ( 74 ) each have a friction surface ( 76 ), which form at least a portion of a torus surface, - that the first torus wheel ( 72 ) and the second torus wheel ( 74 ) are arranged coaxially to each other and the respective friction surfaces ( 76 ) are facing each other, - that the Torusgetriebe ( 70 ) at least one transmission wheel ( 78 ), which at the friction surface ( 76 ) of the first torus wheel ( 72 ) and at the friction surface ( 76 ) of the second torus wheel ( 74 ), and - that a rotation axis ( 80 ) of the transmission wheel ( 78 ) is tiltable. Crankcase ventilation device according to one of claims 1 to 9, characterized in that the pumping device ( 26 ) with a crankshaft, a camshaft or a balance shaft of the internal combustion engine ( 12 ) is coupled. Internal combustion engine with a crankcase ventilation device ( 10 ) according to one of claims 1 to 10, wherein the suction line ( 24 ) of the crankcase ventilation device ( 10 ) the blow-by gases from the crankcase ( 14 ) to an intake tract ( 22 ) of the internal combustion engine ( 12 ).

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