Patent Application
20190032528
The invention relates to an apparatus for ventilating a crankcase of an internal combustion engine, to a method for ventilating a crankcase of an internal combustion engine, and to a vehicle, in particular utility vehicle, having the apparatus and/or for carrying out the method.
It is known to provide, on an internal combustion engine, a crankcase ventilation device by which gases that flow into a crank chamber of the internal combustion engine during the operation of the internal combustion engine, in particular blow-by gases, are conducted out of the crank chamber again and introduced into an intake tract of the internal combustion engine. This counteracts, for example, corrosion of a crankcase of the internal combustion engine and a contamination of the oil sump oil, which has collected in an oil sump of the internal combustion engine, by the gases flowing into the crank chamber. Here, the gases are conventionally conveyed out of the crank chamber by the negative pressure prevailing in the intake tract.
It is furthermore also known for a crankcase ventilation device to be formed with multiple ventilation channels, wherein gas inlet openings, which open into the crank chamber of the internal combustion engine, of the multiple ventilation channels are arranged such that it is always the case, regardless of the inclination or orientation of the internal combustion engine, that at least one ventilation channel does not dip with its gas inlet opening into the oil sump oil. It is thereby ensured that the crank chamber or the crankcase chamber is ventilated even in the case of extreme lateral inclinations, or during uphill and downhill travel, of a vehicle that has the internal combustion engine.
For example, DE 102 38 422 A1 has disclosed a crankcase ventilation device in the case of which, at a clutch side, facing toward a vehicle transmission, of a crankcase, and at an end side of the crankcase situated opposite the clutch side, there is arranged in each case one ventilation line which projects into a crank chamber of the crankcase and which serves for ventilating the crankcase. By this arrangement of the ventilation lines, it is ensured that, when a vehicle that has the internal combustion engine is traveling uphill or downhill, at least one ventilation line is always situated with its gas inlet opening above the oil level of the oil that has collected in an oil sump of the internal combustion engine. It is thereby achieved that the crankcase is reliably ventilated even during uphill and downhill travel.
In the case of such a ventilation arrangement, however, problems arise if a ventilation line dips with its gas inlet opening into the oil sump oil and then a large quantity of oil sump oil is conveyed via the ventilation line into the intake tract of the internal combustion engine. In the worst case, this can lead to severe engine damage.
It is therefore an object of one aspect of the invention to provide a device and a method for ventilating a crankcase of an internal combustion engine for a vehicle, in particular for a utility vehicle, by which the functioning of the crankcase ventilation device is reliably ensured and, at the same time, an introduction of oil into the intake tract of the internal combustion engine is prevented.
An apparatus for ventilating a crankcase of an internal combustion engine for a vehicle, in particular for a utility vehicle, having multiple ventilation channels by which gases flowing into a crankcase chamber of the crankcase are conducted out of the crankcase chamber again, preferably are conducted from the crankcase chamber into an intake tract of the internal combustion engine, wherein gas inlet openings, which open into the crankcase chamber, of the multiple ventilation channels are arranged such that, in a first inclination position of the internal combustion engine, a first ventilation channel does not dip with its gas inlet opening into oil sump oil that has collected in an oil sump of the internal combustion engine and a second ventilation channel dips with its gas inlet opening into the oil sump oil, wherein, in a second defined inclination position, which differs from the first inclination position, of the internal combustion engine, the first ventilation channel dips with its gas inlet opening into the oil sump oil and the second ventilation channel does not dip with its gas inlet opening into the oil sump oil. According to the invention, a control device is provided by which, in particular in order to prevent an introduction of oil sump oil into the intake tract, a fluid flow through the ventilation channels can be shut off and enabled in terms of flow, in particular automatically, in a manner dependent on the inclination of the internal combustion engine, wherein, in the first inclination position of the internal combustion engine, the control device opens up the first ventilation channel and shuts off the second ventilation channel, and wherein, in the second inclination position of the internal combustion engine, the control device opens up the second ventilation channel and shuts off the first ventilation channel.
In this way, the functioning of the crankcase ventilation device is reliably ensured, because, both in the first inclination position and in the second inclination position of the internal combustion engine, it is always the case that one ventilation channel does not dip with its gas inlet opening into the oil sump oil, and the fluid flow through the ventilation channel that does not dip into the oil sump oil is enabled by the control device. At the same time, the apparatus according to one aspect of the invention also prevents an introduction of relatively large oil quantities into the intake tract of the internal combustion engine, because, both in the first inclination position and in the second inclination position of the internal combustion engine, the fluid flow through the ventilation channel that dips into the oil sump oil is shut off by the control device.
Here, the expression “inclination position” is expressly to be understood in a broad sense. Accordingly, the first or the second inclination position of the internal combustion engine may be formed for example by a basic position of the internal combustion engine in which the internal combustion engine is situated when the vehicle that has the internal combustion engine is situated on a level or horizontal plane. Likewise, the first or the second inclination position may however also be formed by a position of the internal combustion engine in which the internal combustion engine has been rotated or pivoted relative to said basic position. Here, it is essential that the internal combustion engine is inclined differently, or oriented differently, in the first inclination position than in the second inclination position.
Furthermore, the apparatus according to the invention is not restricted to a construction with two ventilation channels that open into the crank chamber. It is self-evidently also possible for more than two channels that open into the crank chamber to be provided for ventilating the crankcase.
Here, the gases that flow into the crankcase chamber are preferably conducted from the crankcase chamber into the intake tract of the internal combustion engine by the ventilation channels. It would however alternatively also be conceivable for the gases that flow into the crankcase chamber to be conducted by the ventilation channels directly into the atmosphere or into the surroundings of the apparatus, such that an “open” ventilation arrangement is realized.
In a preferred design embodiment of the apparatus according to one aspect of the invention, the gas inlet openings of the multiple ventilation channels are arranged such that, regardless of the inclination or orientation of the internal combustion engine, it is always the case that at least one ventilation channel does not dip into the oil sump oil. In this way, the functioning of the crankcase ventilation device is ensured in a particularly reliable manner.
It is furthermore preferable if, as viewed in a fluid flow direction, there is provided upstream of the intake tract at least one oil separator element by which oil can be separated off from the fluid flowing via the ventilation channels into the intake tract. An oil separator element of said type serves to prevent no oil from passing via the ventilation channels into the intake tract. Provision is preferably made here whereby, in the first inclination position of the internal combustion engine, the control device shuts off a fluid flow through the second ventilation channel to the at least one oil separator element, and in the second inclination position of the internal combustion engine, said control device shuts off a fluid flow through the first ventilation channel to the at least one oil separator element. This prevents such a large quantity of oil being supplied to the oil separator element that the latter is overloaded or cannot separate off the oil to a sufficient extent.
In a preferred specific design embodiment, the control device has a first shut-off valve for shutting off and opening up the first ventilation channel and a second shut-off valve for shutting off and opening up the second ventilation channel. Using such shut-off valves, the shutting-off and opening-up of the ventilation channels in accordance with the invention can be realized in a simple and functionally reliable manner. It is however self-evidently basically also possible for more than two shut-off valves to be provided for shutting off and opening up the ventilation channels.
The first and/or the second shut-off valve may basically be arranged for example downstream of the at least one oil separator element as viewed in a fluid flow direction. It is however preferable if, as viewed in a fluid flow direction, the first and/or the second shut-off valve is arranged upstream of the at least one oil separator element in order to counteract an overloading of the at least one oil separator element if the respective ventilation channel dips with its gas inlet opening into the oil sump oil.
Preferably, the first and/or the second shut-off valve are assigned to a cylinder head, in particular to a cylinder head cover, of the internal combustion engine, in order to realize a simple and low-maintenance construction. Alternatively and/or in addition, the first and/or the second shut-off valve may however also be assigned to the crankcase of the internal combustion engine in order to ensure that as small an oil quantity as possible flows into the respective ventilation channel if the latter dips into the oil sump oil. This has the advantage inter alia that the oil level in the oil sump is kept higher, and a situation in which an intake opening of an oil pump of the internal combustion engine lies above the oil level is counteracted.
It is furthermore preferable for the first shut-off valve to be arranged in a defined vicinity in the region of the gas inlet opening of the first ventilation channel. In this way, a flow of oil sump oil into the first ventilation channel is counteracted in an effective manner. Alternatively and/or in addition, the second shut-off valve may also be arranged in a defined vicinity in the region of the gas inlet opening of the second ventilation channel.
In a further preferred refinement, the first shut-off valve and at least one oil separator element form a structural unit or installation unit. In this way, the installation of the first shut-off valve and of the at least one oil separator element is considerably simplified. Alternatively and/or in addition, provision may however also be made for the second shut-off valve and at least one oil separator element to form a structural unit. Further alternatively and/or in addition, provision may also be made for the first shut-off valve, the second shut-off valve and at least one oil separator element to form a structural unit, in order to further simplify the installation process and realize a particularly compact construction. Here, the first and the second shut-off valve respectively may be arranged for example at an oil inlet region or at an oil outlet region of the structural unit.
The control device preferably has an inclination detection device by which the present inclination or orientation of the internal combustion engine can be detected, wherein the first and/or the second shut-off valve can be automatically activated or actuated by a control unit of the control device in a manner dependent on the detected present inclination of the internal combustion engine in order to shut off or open up the respective ventilation channel. In this way, a fluid flow through the ventilation channels can be reliably and easily shut off and enabled in terms of flow in a manner dependent on the present inclination of the internal combustion engine.
The inclination detection device is preferably formed by at least one oil quantity sensor by which the oil quantity flowing through the first and/or the second ventilation channel can be measured. By an oil level sensor of said type, the present inclination of the internal combustion engine can be estimated with sufficient accuracy, because, in the situation in which a ventilation channel dips into the oil sump oil, a considerably greater oil quantity is conveyed through the respective ventilation channel than in the situation in which the respective ventilation channel does not dip into the oil sump oil. Furthermore, by an oil quantity sensor of said type, it is possible to detect whether an excessively large oil quantity flows through the respective ventilation channel even independently of whether or not the respective ventilation channel dips into the oil sump oil. Thus, by the oil quantity sensor, the introduction of an excessively large oil quantity into the intake tract is prevented in a particularly reliable manner. The oil quantity flowing through the ventilation channel may in this case be determined for example by the density of the fluid flowing through the ventilation channel or by the oil fraction in the fluid flowing through the ventilation channel.
Alternatively and/or in addition to the oil quantity sensor, the inclination detection device may also be formed by an oil level sensor, by which the level of the oil sump oil that has collected in the oil sump can be measured. The present inclination or orientation of the internal combustion engine can likewise be reliably estimated by the level of the oil sump oil that has collected in the oil sump. Further alternatively and/or in addition, the inclination detection device may also be formed by an inclination sensor, by which the inclination or the orientation of the internal combustion engine can be measured. An inclination sensor of said type may be formed for example by an acceleration sensor.
Alternatively and/or in addition to the activation of the first and/or of the second shut-off valve by the control unit, the first and/or second shut-off valve may also be formed by a float valve, in order for the first and/or second shut-off valve to be designed to be particularly fast-reacting. Provision is preferably made here for a float body of the float valve to be formed as a sealing element, which can be pressed against a corresponding sealing seat in order to shut off the fluid flow through the respective ventilation channel and which opens up a defined flow cross section in order to enable the fluid flow through the respective ventilation channel. The float valve can thus be realized in a simple and functionally reliable form.
The float valve preferably has at least one loading element, in particular a spring element, which preloads the float body arranged in its closed position into its open position. By a loading element of said type, it is reliably ensured that the float valve always opens and closes as desired. In particular, by the loading element, it is possible to prevent the float valve from closing already in the presence of relatively high gas throughputs. The float valve is further preferably arranged in a U limb of a substantially U-shaped ventilation channel section, the U base of which has at least one base-wall-side oil outflow opening for the discharge of oil that has collected in the U base and/or in the U limbs. In this way, a simple and functionally reliable construction is realized. Furthermore, the labyrinthine, U-shaped ventilation channel section acts as a coarse separator for the oil flowing through the ventilation channel.
Alternatively and/or in addition to the embodiment as a float valve, the first and/or the second shut-off valve may also have a sealing body with a defined flow contour, which is pressed against a corresponding sealing seat, in order to shut off the fluid flow through the respective ventilation channel, by the fluid flow and which opens up a defined flow cross section in order to enable the fluid flow through the respective ventilation channel. Accordingly, the first and/or the second shut-off valve can likewise be designed to be particularly fast-reacting and reliable. The sealing body may in this case for example be pressed against the corresponding sealing seat by the fluid flowing through the ventilation channel if the oil quantity flowing through the ventilation channel exceeds a defined oil quantity threshold value. If the oil quantity flowing through the ventilation channel falls below the defined oil quantity threshold value again, the sealing element may then open up a defined flow cross section again. The opening-up and shutting-off of the ventilation channel is in this case thus dependent on the impetus or the dynamic pressure exerted on the sealing body by the fluid flow. This pressure increases with increasing flow speed and increasing density of the fluid flow. The oil quantity threshold value is in this case preferably formed by a defined gas-oil ratio. Provision is preferably furthermore made for the sealing element to be of spherical and/or plate-shaped form and/or to have a defined flow resistance value or cw value.
Further preferably, at least one loading element, in particular a spring element, is provided, which preloads the sealing body arranged in its closed position into its open position in order to be able at all times to open up and shut off the respective ventilation channel as desired by the sealing body. It is furthermore preferable if, as viewed in a fluid flow direction, the sealing body is arranged directly upstream of at least one active or driveable oil separator element, in particular a centrifuge or a disk separator.
Alternatively and/or in addition to the sealing body, the first and/or the second shut-off valve may also have a shut-off element, which is fixed so as to be rotatable relative to the respective ventilation channel about an axis of rotation and which, in a first rotational position, opens up the respective ventilation channel and, in a second rotational position, shuts off the respective ventilation channel, wherein the shut-off element is connected by at least one lever element to a counterweight element that has a defined mass, in such a way that the shut-off element always has the same orientation relative to the horizontal regardless of the inclination of the internal combustion engine about an inclination axis running in a direction of the axis of rotation. By a shut-off valve designed in this way, the shutting-off and opening-up of the respective ventilation channel in accordance with the invention can be realized in a reliable and fast-reacting manner. Provision is preferably made here for the at least one shut-off valve to be formed by a throttle flap and/or by a rotary slide.
To achieve the object stated above, a method for ventilating a crankcase of an internal combustion engine for a vehicle, in particular for a utility vehicle, is furthermore claimed, having multiple ventilation channels by which gases flowing into a crankcase chamber of the crankcase are conducted out of the crankcase chamber again, preferably are conducted from the crankcase chamber into an intake tract of the internal combustion engine, wherein gas inlet openings, which open into the crankcase chamber, of the multiple ventilation channels are arranged such that, in a first defined inclination position of the internal combustion engine, a first ventilation channel does not dip with its gas inlet opening into oil sump oil that has collected in an oil sump of the internal combustion engine, wherein, in a second defined inclination position, which differs from the first inclination position, of the internal combustion engine, the first ventilation channel dips with its gas inlet opening into the oil sump oil and the second ventilation channel does not dip with its gas inlet opening into the oil sump oil. According to the invention, a control device is provided by which, in particular in order to prevent an introduction of oil sump oil into the intake tract, a fluid flow through the ventilation channels is shut off and enabled in terms of flow, in particular automatically, in a manner dependent on the inclination of the internal combustion engine, wherein, in the first inclination position of the internal combustion engine, the control device opens up the first ventilation channel and shuts off the second ventilation channel, and wherein, in the second inclination position of the internal combustion engine, the control device opens up the second ventilation channel and shuts off the first ventilation channel.
The advantages that arise from the method implementation according to the invention are identical to the already-discussed advantages of the apparatus according to the invention, and will not be repeated at this juncture.
Also claimed is a vehicle, in particular a utility vehicle, having the apparatus according to the invention and/or for carrying out the method according to the invention. The advantages that arise from this equate to the already-discussed advantages of the apparatus according to the invention and will likewise not be repeated here. Preferably, the vehicle is formed here by a vehicle which is subject to increased longitudinal and/or transverse acceleration, because it is here that the apparatus according to the invention and the method according to the invention are particularly effective. A vehicle of said type may be formed for example by an off-road vehicle or by a ship.
The advantageous embodiments and/or refinements of the invention discussed above and/or defined in the subclaims may—other than for example in the cases of unique dependencies or non-combinable alternatives—be used individually or else in any desired combination with one another.
The invention and the advantageous embodiments and/or refinements thereof, and the advantages thereof, will be discussed in more detail below, merely by way of example, on the basis of drawings.
In the drawings:
The ventilation channels 13, 15 are formed here for example by pipelines that are joined in each case by one end region to the crankcase 7 and by their other end region to a joining region 27 to the ventilation channel 17, which in this case is likewise formed as a pipeline. Gas inlet openings 29 of the ventilation channels 13, 15 are in this case arranged, as viewed in an internal combustion engine transverse direction y, opposite one another laterally at the outside on the crankcase 7. By this arrangement, it is achieved that, in the case of any regular inclination of the internal combustion engine 3 about a longitudinal axis formed by the internal combustion engine longitudinal direction x (
Furthermore, in this case, the gas inlet openings 29 of the ventilation channels 13, 15 are also arranged such that, in defined first inclination positions of the internal combustion engine, the ventilation channel 13 does not dip with its gas inlet opening 29 into the oil sump oil that has collected in the oil sump 5, and the ventilation channel 15 dips with its gas inlet opening 29 into the oil sump oil that has collected in the oil sump 5. In defined second inclination positions of the internal combustion engine 3, however, the ventilation channel 13 dips with its gas inlet opening 29 into the oil sump oil, whereas the ventilation channel 15 in this case then does not dip with its gas inlet opening 29 into the oil sump oil.
As can also be seen from
Here, the actuation of the shut-off valves 31, 33 is performed in a manner dependent on the inclination of the internal combustion engine 3. Specifically, in this case, in the abovementioned first inclination positions of the internal combustion engine 3, for example beyond an inclination of 20° of the internal combustion engine in a first direction about the longitudinal axis, the ventilation channel 13 is opened up by the shut-off valve 31 and the ventilation channel 15 is shut off by the shut-off valve 33. Furthermore, in the likewise abovementioned second inclination positions of the internal combustion engine 3, for example beyond an inclination of 20° of the internal combustion engine in a second direction, which is opposite to the first direction, about the longitudinal axis, the ventilation channel 15 is opened up by the shut-off valve 33 and the ventilation channel 13 is shut off by the shut-off valve 31. In this way, it is reliably ensured that the oil sump oil is not conducted or conveyed into the intake tract 21 of the internal combustion engine 3 via a ventilation channel 13, 15 that is dipping into the oil sump oil. Exemplary embodiments of the shut-off valves 31, 33 will be discussed in more detail further below. Further embodiments of the apparatus according to the invention will now be discussed in more detail below. The basic functioning of these apparatuses is however identical to the functioning of the first embodiment discussed above.
Furthermore, here, each ventilation channel 13, 15 is assigned an oil separator element 35, which is arranged downstream of the respective shut-off valve 31, 33 as viewed in a fluid flow direction and by which oil can be separated off from the fluid flowing through the respective ventilation channel 13, 15. The shut-off valve 31 and the oil separator element 35 of the ventilation channel 13 in this case furthermore form a structural unit 41. The shut-off valve 33 and the oil separator element 35 of the ventilation channel 15 also form a structural unit 43 here. It is furthermore also the case here that each ventilation channel 13, 15 opens into the intake tract 21 (not illustrated in
Furthermore, gas inlet openings 73 of the ventilation channels 67 are in this case arranged so as to be distributed uniformly over the crank chamber 19 in an internal combustion engine longitudinal direction x. It is achieved in this way that, in any inclination of the internal combustion engine 3 about a transverse axis formed by the internal combustion engine transverse direction y (
Here, it is furthermore the case that the four ventilation channels 67 are joined, at a joining region 77, to form three ventilation channels or ventilation lines 79. Here, each ventilation channel 79 is furthermore assigned an oil separator element 81 for separating off oil from the fluid flowing in the respective ventilation channel 79. It is furthermore the case here that the ventilation channels 79 open into the intake tract 21 (not illustrated in
As can be seen from
Here, if the oil quantity measured by the oil quantity sensor 89 exceeds a defined oil quantity threshold value the shut-off valve 31 is activated by the control unit 91 such that the shut-off valve 31 shuts off the ventilation channel 13. If the oil quantity measured by the oil quantity sensor 89 falls below the defined oil quantity threshold value, the shut-off valve 31 is activated by the control unit 91 such that the shut-off valve 31 opens up the ventilation channel 13.
The shut-off valve 31 has in this case a float body 101 formed as a sealing element and which is pressed against a corresponding sealing seat 103 in order to shut off the fluid flow through the ventilation channel 13 and which opens up a defined flow cross section in order to enable the fluid flow through the ventilation channel 13. Here,
Furthermore, the float body 101 in this case also has, by way of example, a flow-optimized region 104, the cross section of which in this case, by way of example, increases in a fluid flow direction. The flow-optimized region 104 is in this case formed such that the float body 101 is pressed against the sealing seat 103, in order to shut off the fluid flow through the ventilation channel 13, by the fluid flow and opens up a defined flow cross section in order to enable the fluid flow through the ventilation channel 13.
As can also be seen from
Here,
Here,
While there have been shown, described and pointed out fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions and substitutions and changes in the form and details of the methods described and the devices illustrated, and in theft operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, it is expressly intended that all combinations of those elements and/or method steps which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Moreover, it should be recognized that structures and/or elements and/or method steps shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102016000632.3 | Jan 2016 | DE | national |
This is a U.S. national stage of application No. PCT/EP2017/000048 filed 18 Jan. 2017. Priority is claimed on European Application No. 10 2016 000 632.3 filed 25 Jan. 2016, the content of which is incorporated herein by reference in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2017/000048 | 1/18/2017 | WO | 00 |
