Crankcase gas separator

Abstract

The present disclosure relates to a crankcase gas separator (2) comprising: a separator housing (4) defining at least a portion of a separation space (6); a rotor (8) arranged in the separation space (6); a gas outlet channel (10) from the separation space (6); and a gas pressure regulating valve (12) arranged in fluid communication with the gas outlet channel (10). The rotor (8) comprises a separation aid in the form of a stack (26) of separation discs (28). The gas pressure regulating valve (12) includes a valve seat (32) and a diaphragm (34) configured to seal against the valve seat (32) and provide a flow direction for gas from the gas outlet passage (10) through the gas pressure regulating valve (12). The diaphragm (34) is arranged downstream of the valve seat (32) with respect to the flow direction.

Description

Technical Field

[0001] The invention relates to a crankcase gas separator. Background Art

[0002] Crankcase gases are vented from the crankcase of an internal combustion engine (ICE). Crankcase gases are the result of high pressure within the cylinders of the ICE forcing some of the combustion gases and liquid and solid residues down past the piston rings into the crankcase of the ICE. If not vented, the increased pressure within the crankcase may impede ICE operation, may cause engine oil to leak out of the ICE, and / or may cause liquid and solid residues to contaminate and / or dilute the engine lubricating oil.

[0003] The exhaust crankcase gases can be treated in an environmentally friendly manner instead of being discharged to the atmosphere in untreated form. For certain types of combustion engines, it is a legal requirement to treat the crankcase gases in an environmentally friendly manner.

[0004] The crankcase gas comprises combustion gases, oil, other liquid hydrocarbons, soot and other solid combustion residues. In order to properly treat the crankcase gas, the gas is separated from the oil, soot and other residues. The separated gas can be directed to the intake of the combustion engine or discharged to the atmosphere, and the oil can be directed back to the oil sump of the combustion engine, optionally via an oil filter for removing soot and other solid residues from the oil.

[0005] A separator may be used to process the crankcase gas. In the separator, the crankcase gas is separated into heavy components of the crankcase gas (such as oil and soot) and a purified gas phase. Depending on the type of separator used, the heavy components are collected in the separator or directed out of the separator via an outlet. The gas phase is directed out of the separator via a gas outlet and may be directed to the intake of an ICE.

[0006] The pressure at the air intake of an ICE is usually below atmospheric pressure, for example, due to the ICE's turbocharger rotating at high speed to compress the air that has been drawn into the ICE. Therefore, this sub-atmospheric pressure also prevails at the gas outlet of the crankcase gas separator connected to the air intake. A gas pressure regulating valve may be arranged at the gas outlet in order to prevent excessive sub-atmospheric pressure from propagating through the crankcase gas separator to the crankcase of the associated ICE, which is undesirable.

[0007] On the other hand, when the turbocharger is not rotating or is rotating only at a low speed, it does not build up any sub-atmospheric pressure that can propagate through the crankcase gas separator.

[0008] There are different types of crankcase gas separators. One way to categorize crankcase gas separators may be into passive and active types.

[0009] In a passive type of crankcase gas separator, the overpressure of the crankcase (i.e., a pressure above atmospheric pressure at the inlet of the crankcase gas separator) and the pressure below atmospheric pressure at the gas outlet of the crankcase gas separator convey the gas through the separator. In other words, no energy is supplied to the crankcase gas flowing through the separator in the crankcase gas separator itself.

[0010] Passive type crankcase gas separators may rely on a filter element (such as a mesh filter) and / or rely on a change in direction of gas flow through the crankcase gas separator to separate heavy components from the crankcase gases.

[0011] In ICE operating conditions, when the turbocharger does not build up any pressure below atmospheric pressure, a passive type crankcase gas separator does not contribute to extracting crankcase gases from the associated ICE. Instead, the overpressure generated in the crankcase of the ICE forms the only way to guide the crankcase gases through the separator. This may not always be sufficient to remove the heavy components from the crankcase gases.

[0012] In an active type of crankcase gas separator, energy is supplied in the separator to the crankcase gases flowing therethrough. Thus, in ICE operating conditions, when the turbocharger does not build up any pressure below atmospheric pressure, the crankcase gases are extracted from the associated ICE by the crankcase gas separator and their heavy components are removed therein.

[0013] One type of active crankcase gas separator comprises a rotor that is actively driven in rotation. The rotation generates centrifugal forces acting on the heavy components of the crankcase gas, thus promoting and / or improving their separation. In addition, the rotor has a pumping effect, i.e. a pressure increasing effect, on the crankcase gas and the purified gas passing through the crankcase gas separator.

[0014] Therefore, since the passive type crankcase gas separator relies on the gas pressure outside the separator and the pressure drop across the separator to separate the heavy components, and since the active type crankcase gas separator is driven to separate the heavy components, the pressure distribution within the corresponding separator type, the pressure drop across the corresponding separator type, and the gas flow conditions within the corresponding separator type are significantly different in the passive type crankcase gas separator and the active type crankcase gas separator.

[0015] Therefore, any valve operating to control the flow of gas through a separator of the passive type has operating conditions that are significantly different from those of a valve of a separator of the active type. Among other things, the valve of a separator of the passive type must ensure sufficient gas passage to enable separation of the heavy components, while the valve of an active type separator must be adapted to operate under the pressure increase caused by the rotor.

[0016] For example, US7704300 and WO2010 / 051994 show crankcase gas separators of active type, wherein the gas outlet is provided with a gas pressure regulating valve adapted to operate under conditions of pressure increase caused by the rotor of the associated separator. Summary of the invention

[0017] Improving the efficiency of internal combustion engines is a goal in the development of such engines. In other words, it is desirable to reduce the energy consumption of the engine (including its auxiliary components, such as active crankcase gas separators).

[0018] It would therefore be desirable to provide a crankcase gas separator comprising a rotor having lower energy consumption than any crankcase gas separator disclosed in US7704300 or WO2010 / 051994. To better address one or more of these problems, a crankcase gas separator is provided having the features defined in the independent claims.

[0019] According to one aspect of the present invention, a crankcase gas separator is provided, which includes: a separator housing, which defines at least a portion of a separation space; a rotor, which is arranged in the separation space; a gas outlet channel from the separation space; and a gas pressure regulating valve, which is arranged to be fluidically connected to the gas outlet channel, wherein the gas pressure regulating valve includes a valve seat and a diaphragm, the diaphragm is configured to seal against the valve seat and provide a flow direction for gas from the gas outlet channel through the gas pressure regulating valve, wherein the diaphragm is arranged downstream of the valve seat relative to the flow direction.

[0020] Since the diaphragm is arranged downstream of the valve seat relative to the flow direction, the pressure drop prevailing over the gas pressure regulating valve when the valve is open is lower than the pressure drop in regulating valves of the type shown in US7704300 and WO2010 / 051994, each of which has a diaphragm arranged upstream of the valve seat.

[0021] Since the pumping of crankcase gas and purge gas actuated by the rotating rotor operates against this lower pressure drop across the regulating valve, less energy is required to pump gas out of the crankcase gas separator than in a crankcase gas separator having a valve with its diaphragm arranged upstream of the valve seat. Consequently, less energy is consumed by the present crankcase gas separator and, consequently, also by the internal combustion engine comprising the crankcase gas separator.

[0022] Furthermore, in regulating valves of the type shown in US7704300 and WO2010 / 051994, where the diaphragm is arranged upstream of the valve seat, a small valve seat is required in order to provide the desired uniform valve characteristic. A small valve seat generates a higher pressure drop than a larger valve seat.

[0023] It has been realised by the inventors that in the present gas pressure regulating valve, where the diaphragm is arranged downstream of the valve seat, the situation is reversed and a large valve seat is required in order to provide the desired uniform valve characteristic. Thus, a uniform valve characteristic is provided in a valve with a low pressure drop, compared to a small valve seat in a regulating valve of the type shown in US7704300 and WO2010 / 051994.

[0024] In this context, a large valve seat may be defined as a valve seat with a flow area in the range of 2x Amin to 5x Aclose. The flow area of ​​the valve seat may be viewed perpendicular to the valve seat. Amin is the minimum cross-sectional area through which the gas passes in the separator. Depending on the separator, Amin may be the total area of ​​the gaps between the separation aids at the crankcase gas inlet of the separator, at the center of the rotor, at the gas outlet channel upstream of the gas pressure regulating valve, etc. Aclose is the closing area of ​​the diaphragm, i.e. the area of ​​the diaphragm outside the valve seat, see further below.

[0025] The crankcase gas separator is arranged for purifying crankcase gases from an internal combustion engine (ICE).Such an ICE may be configured for propelling a vehicle, a ship, or may be a stationary combustion engine, for example for driving a generator to generate electric current.

[0026] The crankcase gas separator is configured to separate the heavy components of the crankcase gas as a liquid phase from the gas phase. Thus, the liquid phase may include one or more of oil, other liquid hydrocarbons, soot, and other solid combustion residues.

[0027] Crankcase gases, also known as blow-by gases, may be exhausted from the crankcase of the ICE via a crankcase ventilation system. A centrifugal separator may form part of the crankcase ventilation system.

[0028] In the separation space and rotor of the crankcase gas separator, the crankcase gas is separated into a liquid phase and a gas phase.

[0029] The crankcase gas separator is a centrifugal separator, as it comprises a rotor arranged in a separation space. The rotor may be connected to a rotor shaft, which is journalled in a separator housing and arranged to rotate about a rotation axis.

[0030] If not stated otherwise, axial and radial references and directions used herein are defined relative to the axis of rotation of the rotor.

[0031] In this document, the crankcase gas separator may alternatively be simply referred to as a separator, or as a centrifugal separator; the gas pressure regulating valve may alternatively be referred to as a pressure regulating valve, a regulating valve, or as a valve.

[0032] The separator comprises an inlet for crankcase gas. The inlet is arranged to be in fluid communication with the separation space. A gas outlet channel is also arranged to be in fluid communication with the separation space. The gas outlet channel forms part of a gas outlet for the gas phase separated in the separator. The crankcase gas separator comprises a liquid outlet for the liquid phase separated in the separator. The liquid outlet is also arranged to be in fluid communication with the separation space.

[0033] In operation of the centrifugal separator, crankcase gas is guided into the separation space and the rotor via an inlet for crankcase gas. The crankcase gas enters the rotor from its central part. As the rotor rotates, heavy components are separated therein and are pushed as droplets from the outer periphery of the rotor against the circumferential inner wall surface of the separator housing. The droplets form a separated liquid phase, which is guided out of the centrifugal separator via a liquid outlet. The gas phase, i.e. the crankcase gas from which its heavy components have been removed, is guided out of the centrifugal separator via a gas outlet channel and a gas pressure regulating valve.

[0034] The rotation of the rotor has a pumping effect on the crankcase gases and the gas phase, which increases the gas pressure between the inlet and gas outlet passages for the crankcase gases.

[0035] The centrifugal separator can be configured to separate simultaneously. That is, the two separated phases travel in the same direction through the rotor of the centrifugal separator. More specifically, as discussed above, the liquid phase travels from the inside of the rotor to its periphery. Similarly, the gas phase is formed when the crankcase gas separates from the heavy components as it travels from the central portion of the rotor to its periphery. Therefore, both the liquid phase and the gas phase leave the rotor at the periphery of the rotor.

[0036] The rotor may include separation aids, such as a plurality of separation elements, which improve the separation of the heavy components from the crankcase gas. The separation aids may include separation elements, such as in the form of axially extending guide vanes or axially stacked frustoconical separation disks directed radially from the rotor shaft. As the rotor rotates, the heavy components are forced against radially inward surfaces of the separation elements, forming liquid phase droplets thereon and flowing toward the periphery of the rotor.

[0037] The separator housing is stationary relative to the ICE. The rotor shaft and rotor are arranged to rotate relative to the separator housing. The rotor shaft may be rotated by a drive member, such as a turbine wheel, an electric, pneumatic or hydraulic motor, etc.

[0038] The gas pressure regulating valve is configured to regulate the gas pressure in the separation space. For example, the pressure regulating valve can ensure that the minimum pressure level in the separation space does not drop below the minimum pressure level. That is, below the minimum pressure level, the pressure regulating valve can close the gas outlet channel, and above the minimum pressure level, the pressure regulating valve can open the gas outlet channel.

[0039] The gas outlet channel may extend at least upstream of the valve seat, ie form at least a part of the flow path between the separation space and the valve seat.

[0040] In this context, the diaphragm being configured to abut and / or seal against the valve seat does not necessarily mean a gas-tight seal, but rather that at least a portion of the diaphragm abuts against a portion of the valve seat. Thus, the abutment and / or sealing achieved may more or less reduce the gas passage.

[0041] For example, the diaphragm may generally extend substantially perpendicular to a plane including the valve seat, for example, the plane of the abutment area of ​​the diaphragm may extend within a range of 0-5 degrees relative to a plane including the valve seat. For example, if there is an angle between the two planes, as the pressure differential across the valve seat increases, the diaphragm will gradually abut against the valve seat, with the lower pressure being on the downstream side of the regulating valve.

[0042] The terms upstream and downstream refer to directions or positions viewed along the flow direction, i.e. upstream is closer to the flow source and downstream is further away from the flow source. For example, in the present case, the diaphragm being arranged downstream of the valve seat means that components of the gas flowing through the pressure regulating valve will reach the valve seat before reaching the diaphragm.

[0043] The expression "flow direction of gas from the gas outlet passage through the gas pressure regulating valve" generally refers to the flow direction through the regulating valve from its inlet to its outlet. Thus, along this flow direction, the physical path of the gas flowing through the regulating valve may change direction one or more times.

[0044] A spring or other resilient member may be arranged to interact with the diaphragm to provide the desired opening and / or closing characteristics of the valve.

[0045] According to an embodiment, viewed perpendicularly to a plane including the valve seat, a gas flow area inside the valve seat and an area of ​​the diaphragm outside the valve seat may have a ratio in the range of 1:1.25 to 1:5. In this way, a smooth valve characteristic may be provided.

[0046] Furthermore, within this range, the characteristic of a regulating valve can be achieved, namely the valve is closed by means of a diaphragm arranged downstream of the valve seat to prevent an excessively low pressure downstream of the valve from propagating through the valve and the separator.

[0047] The gas flow area in the valve seat, or more specifically its projected area on the diaphragm, serves as the opening area of ​​the valve / diaphragm. The area of ​​the diaphragm outside the valve seat, i.e. the area having an annular shape in the case of a substantially circular diaphragm, serves as the closing area of ​​the valve / diaphragm.

[0048] According to an embodiment, the center of the diaphragm can be offset from the center of the valve seat when viewed perpendicular to the general plane of the diaphragm. In this way, the pressure drop characteristics of the regulating valve can be adjusted in response to the physical positioning of the components of the regulating valve. For example, relative to a gas outlet conduit for the gas phase of the regulating valve, the conduit being arranged downstream of the diaphragm.

[0049] The general plane of the diaphragm is the flat plane that extends parallel to the widest part of the diaphragm.

[0050] According to an embodiment, the center of the diaphragm may be offset from the center of the valve seat towards the gas outlet conduit. In this way, a low pressure drop may be provided compared to a diaphragm centered relative to the valve seat.

[0051] According to an embodiment, a plane comprising the plane of the valve seat and an abutment area of ​​the diaphragm (which is configured to abut against the valve seat) can be arranged at an angle to each other. In this way, oscillating vibrations in the diaphragm and / or oscillating closing and opening movements of the diaphragm against the valve seat can be avoided, because the diaphragm can gradually come into contact with the entire valve seat.

[0052] Further features of, and advantages with, the present invention will become apparent when studying the appended claims and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Various aspects and / or embodiments of the present invention, including particular features and advantages thereof, will be readily understood from the example embodiments discussed in the following detailed description and accompanying drawings, in which:

[0054] Figure 1 schematically shows a cross section through a crankcase gas separator according to an embodiment,

[0055] Figure 2 Schematically shows the Figure 1 A cross section of a portion of a crankcase gas separator is shown in FIG. 1 , and

[0056] Figure 3a and 3b An embodiment of a gas pressure regulating valve of a crankcase gas separator is schematically shown. DETAILED DESCRIPTION

[0057] Aspects and / or embodiments of the present invention will now be described more fully. Like numbers throughout the text represent like elements. For the sake of brevity and / or clarity, well-known functions or structures will not necessarily be described in detail.

[0058] Figure 1 A cross section through a crankcase gas separator 2 according to an embodiment is schematically shown.

[0059] The separator 2 is a centrifugal separator and is configured to separate a liquid phase and a gas phase from crankcase gas from an internal combustion engine (ICE).

[0060] The separator 2 comprises a separator housing 4 delimiting at least a part of a separation space 6 and a rotor 8 arranged in the separation space 6. During use of the separator 2, crankcase gas is separated in the rotor 8 into a liquid phase and a gas phase.

[0061] The separator 2 further comprises a gas outlet channel 10 from the separation space 6 and a gas pressure regulating valve 12 arranged in fluid communication with the gas outlet channel 10 .

[0062] The gas outlet channel 10 is configured for conducting the separated gas phase out of the separation space 6 and towards the valve 12. Thus, the separation space 6 is arranged in fluid communication with the regulating valve 12 via the gas outlet channel 10.

[0063] Downstream of the regulating valve 12, a gas outlet 13 is provided for the gas phase coming from the separator 2. The gas outlet 13 may be connected to the air intake of the associated ICE upstream of its turbocharger.

[0064] Figure 1 Schematically indicated in the figure is a gas pressure regulating valve 12. The valve 12 may be a biased valve configured to open when a predetermined minimum gas pressure level prevails in the separation space 6. Thus, the valve 12 ensures that the gas pressure within the separation space 6 is above the predetermined minimum gas pressure level. The valve 12 prevents an excessively low pressure of a gas outlet 13 connected to the valve 12 from extracting an excessive amount of crankcase gas from the associated ICE through the separator 2.

[0065] The rotor shaft 14 extends in an axial direction through the separation space 6. The rotor 8 is connected to the rotor shaft 14. The rotor 8 and the rotor shaft 14 are arranged to rotate about an axis of rotation 16.

[0066] The rotor shaft 14 is rotated about the rotation axis 16 by the drive member 18. Figure 1 In the embodiment shown in FIG, drive component 18 is a turbine wheel connected to rotor shaft 14. The turbine wheel is driven by a flow of oil (such as engine lubricating oil) directed toward the turbine wheel.

[0067] The rotor shaft 14 is journaled in the separator housing 4. The rotor shaft 14 can be journaled, for example, in a ball bearing, a roller bearing or a plain bearing.

[0068] In the illustrated embodiment, the operating position of the separator 2 is shown with the rotation axis 16 in a vertical orientation. In alternative embodiments, the operating position may be with the rotation axis in a horizontal orientation or in an orientation between vertical and horizontal.

[0069] Suitably, the separator 2 also comprises an inlet 22 for the crankcase gases to enter the separation space 6 and a liquid outlet 24 for the separated liquid phase.

[0070] exist Figure 1 In the embodiment of the present invention, the separated liquid phase flows from the separation space 6 through the lower bearing to the liquid outlet 24. Additionally or alternatively, other flow paths for the liquid phase from the separation space 6 to the liquid outlet 24 may be provided.

[0071] The rotor 8 comprises a separation aid in the form of a stack 26 of separation discs 28, each of which has a frustoconical shape. Gaps are formed between the separation discs 28 in the stack 26, through which the crankcase gas travels from the inner periphery to the outer periphery while being separated into a liquid phase and a gas phase as the rotor 8 rotates. Figure 1 Only some of the separation discs 28 are indicated.

[0072] In these embodiments, the frustoconical separation discs 28 are stacked so that their wide ends face downwards. In alternative embodiments, the frustoconical separation discs may be stacked so that their wide ends face upwards.

[0073] In alternative embodiments, other types of separation aids may be utilized, such as, for example, axially extending guide vanes that project radially outward from the rotor shaft.

[0074] The centrifugal separator 2 is configured for simultaneous separation. During use of the separator 2, crankcase gas enters the rotor 8 from the central portion of the rotor 8. As the rotor 8 rotates, heavy components separate therein and are pushed as droplets from the outer periphery of the rotor 8 against the circumferential inner wall surface 30, which extends circumferentially around the rotor 8 and may form part of the housing 4.

[0075] When, as shown, the separator 2 is configured to be positioned such that the rotation axis 16 extends substantially vertically during use of the separator 2, the liquid outlet 24 is arranged at the lower end of the housing 4. Thus, the separated liquid phase can be conveyed towards the liquid outlet 24 by gravity.

[0076] If the separator is suitably configured for a different orientation during use, the liquid outlet is arranged at the lower end of the housing in the relevant orientation.

[0077] Figure 1 The flow of crankcase gas, gas phase and liquid phase through separator 2 is indicated by small arrows.

[0078] Figure 2 Schematically shows the Figure 1 A cross section of a portion of the crankcase gas separator 2 is shown in FIG. Figure 2 The gas pressure regulating valve 12 is shown in more detail in FIG. Figure 1 .

[0079] The gas pressure regulating valve 12 includes a valve seat 32 and a diaphragm 34 configured to seal against the valve seat 32. The regulating valve 12 provides a flow direction of gas from the gas outlet channel 10 through the gas pressure regulating valve 12. The flow direction of gas from the gas outlet channel 10 through the regulating valve 12 and to the gas outlet 13 of the separator 2 is Figure 2 Therefore, the gas outlet 13 of the separator 2 is arranged downstream of the membrane 34 .

[0080] The diaphragm 34 is arranged downstream of the valve seat 32 with respect to the flow direction of the gas from the gas outlet channel 10 .

[0081] The regulating valve 12 is arranged to regulate the pressure in the separation space 6 of the separator 2. The relatively high pressure in the separation space 6 acts on the central part of the diaphragm 34 via the gas outlet channel 10 to separate the diaphragm 34 from the valve seat 32, so as to open the valve 12. The relatively low pressure connected to the gas outlet 13 of the separator 2 acts on the peripheral part of the diaphragm 34 to seal the diaphragm 34 against the valve seat 32, so as to close the valve 12.

[0082] Mentioned merely as an example, at least a portion of the diaphragm 34 may be made from an elastomer, such as a thermoplastic elastomer, natural rubber, or synthetic rubber.

[0083] The ratio of the gas flow area in the valve seat 32 to the area of ​​the diaphragm 34 outside the valve seat 32 can be in the range of 1:1.25 to 1:5 when viewed perpendicularly to the plane 38 including the valve seat 32. Figure 2 It is indicated by a dotted line 38 in the middle.

[0084] By way of example, in the case of a circular valve seat 32 with a flow area having a diameter d and a circular diaphragm 34 having a diameter D, the above-mentioned ratio can be expressed as: 1: (D x D / 4 - dxd / 4) / (dxd / 4).

[0085] The diaphragm 34 may generally extend substantially parallel to a plane 38 including the valve seat 32. For example, an abutment plane 39 of the diaphragm 34 configured to abut against the valve seat 32 may extend relative to the plane 38 including the valve seat 32 within a range of 0 to 5 degrees.

[0086] The abutment plane 39 of the diaphragm 34 is a plane of the abutment area of ​​the diaphragm 34 that is configured to abut against the valve seat 32. Figure 2 It is indicated by a dotted line 39 in the middle.

[0087] The gas pressure regulating valve 12 further comprises a biasing member 36 arranged to bias the diaphragm 34 in a direction away from the valve seat 32. In this way, the temperature dependence of the diaphragm characteristics can be equalized or at least reduced. That is, in this way, the physical properties of the diaphragm 34 and the biasing member 36 jointly determine the characteristics of the valve 12.

[0088] In the illustrated embodiment, the biasing member 36 is schematically illustrated as a compression spring. That is, when the diaphragm 34 moves toward the valve seat 32, the compression spring is compressed by the diaphragm 34. The spring force that forces the compression spring to return to its initial length biases the diaphragm 34 in a direction away from the valve seat 32.

[0089] Any alternative other suitable element may be used as the biasing member 36 .

[0090] Biasing member 36 biases diaphragm 34 to an open position, thereby allowing gas phase to flow through valve 12, such as Figure 2 . However, if the pressure downstream of the diaphragm 34 (i.e., at the gas outlet 13) is at such a low level that the resulting force affecting the diaphragm 34 exceeds the sum of the force of the biasing member 36, the force of the inherent elasticity of the diaphragm 34, and the force caused by the pressure affecting the diaphragm 34 upstream of the valve seat 32, the valve 12 will close. Once the pressure difference between upstream and downstream of the valve seat 32 is such that the sum of the force of the biasing member 36, the force of the inherent elasticity of the diaphragm 34, and the force caused by the pressure affecting the diaphragm 34 upstream of the valve seat 32 causes the diaphragm 34 to move away from the valve seat 32, the valve 12 will open again.

[0091] According to some embodiments, such as the illustrated embodiment, the gas outlet channel 10 from the separation space 6 can be connected to the inlet channel 40 of the gas pressure regulating valve 12, wherein the inlet channel 40 leads to the valve seat 32. In this way, the gas outlet channel 10 from the separation space 6 can transition into the inlet channel 40 of the gas pressure regulating valve 12.

[0092] According to an embodiment, such as the one shown, the inlet channel 40 of the gas pressure regulating valve 12 may extend substantially perpendicularly to the plane 38 including the valve seat 32. In this way, the regulating valve 12 may be adapted to be positioned so that the plane 38 of the valve seat 32 extends substantially tangentially to the separation space 6. This in turn provides a compact separator 2, since the diaphragm 34 may thus also be positioned to extend substantially tangentially to the separation space 6. Thus, in this way, the valve 12 may be designed to be arranged close to the housing 4 of the separator 2.

[0093] According to embodiments, such as the one shown, the valve closing movement of the diaphragm 34 may be in a direction opposite to the direction of gas flow into the gas pressure regulating valve 12. This arrangement is a result of the diaphragm 34 being arranged downstream of the valve seat 32.

[0094] The direction of gas flowing into the gas pressure regulating valve 12 is provided by the inlet passage 40 of the regulating valve 12 being directed towards the diaphragm 34 .

[0095] The direction of the gas flowing into the regulating valve 12 has a physical direction as it flows through the inlet passage 40 of the regulating valve 12 to the valve seat 32 thereof.

[0096] According to an embodiment, such as the one shown, the gas pressure regulating valve 12 may comprise a gas outlet duct 42 downstream of the diaphragm 34, wherein the gas outlet duct 42 may extend substantially parallel to the diaphragm 34. In this way, a compact separator 2 may be provided, since the gas outlet duct 42 may be arranged to lead parallel to a tangent to the separation space 6 and the housing 4 of the separator 2.

[0097] Depending on the associated ICE relative to which the separator 2 is to be mounted, the gas outlet conduit 42 may be arranged to point in a suitable direction while extending substantially parallel to the membrane 34 .

[0098] Further ducting (not shown) leading from the gas outlet duct 42 to, for example, a turbocharger of an associated ICE may have to be directed away from the separator 2 in order to reach the turbocharger. However, the gas outlet duct 42 extends substantially parallel to the membrane 34 so that the separator 2 can be easily positioned relative to the ICE.

[0099] The expression "substantially parallel to the diaphragm 34" in this context may be, for example, within a range of -10 degrees to 10 degrees of the plane of the diaphragm 34, such as the indicated abutment plane 39 or the general plane of the diaphragm 34. As mentioned above, the general plane of the diaphragm 34 is a flat plane extending parallel to the widest portion of the diaphragm 34.

[0100] Figure 3a and 3b The gas pressure regulating valve 12 according to an embodiment is schematically shown. The regulating valve 12 is a valve of a crankcase gas separator including a rotor, such as the one described above with reference to Figure 1 and 2 Discussed separator 2. Figure 3a shows a cross section through valve 12, and Figure 3b A top view of selected components of valve 12 is shown.

[0101] Figure 3a and 3b The regulating valve 12 and Figure 2 The control valve 12 of FIG. 1 is very similar to that of FIG. 1 . Therefore, the differences will be mainly discussed below.

[0102] Again, the valve 12 comprises a valve seat 32 and a diaphragm 34 configured to seal against the valve seat 32. Downstream of the diaphragm 34, a gas outlet 13 for the gas phase of an associated crankcase gas separator is arranged.

[0103] Again, the regulating valve 12 provides a flow direction of gas from the gas outlet channel 10 through the gas pressure regulating valve 12. With respect to the flow direction of gas from the gas outlet channel 10, the diaphragm 34 is arranged downstream of the valve seat 32.

[0104] Again, viewed perpendicularly to the plane 38 including the valve seat 32, the gas flow area inside the valve seat 32 and the area of ​​the diaphragm 34 outside the valve seat 32 have a ratio in the range of 1:1.25 to 1:5. Figure 3a It is indicated by a dot-dash line 38 in the middle.

[0105] exist Figure 3a and 3b In FIG. 1 , the valve 12 is shown in the open state and the flow of the separated gas phase through the valve seat 32, through the membrane 34 and through the gas outlet 13 for the gas phase is shown in FIG. Figure 3b Indicated by arrows.

[0106] Again, the valve 12 includes a biasing member 36 arranged to bias the diaphragm 34 in a direction away from the valve seat 32 .

[0107] In these embodiments, the biasing member 36 is schematically illustrated as a tension spring connected to the diaphragm 34 and the housing components of the valve 12. Thus, when the diaphragm 34 moves toward the valve seat 32, the tension spring is extended by the diaphragm 34. The spring force urging the tension spring to return to its initial length biases the diaphragm 34 in a direction away from the valve seat 32.

[0108] Again, the gas outlet channel 10 from the separation space 6 can be connected to an inlet channel 40 of the gas pressure regulating valve 12 , which inlet channel 40 opens into the valve seat 32 .

[0109] Again, the inlet passage 40 of the gas pressure regulating valve 12 may extend substantially perpendicular to the plane 38 including the valve seat 32 .

[0110] In the present context, the expression “substantially perpendicular to a plane 38 comprising the valve seat 32 ” may, for example, relate to a minimum angle β between the plane 38 and a center line 41 extending along the inlet channel 40 in the range of 90 to 85 degrees.

[0111] Again, the gas pressure regulating valve 12 may include a gas outlet conduit 42 downstream of the diaphragm 34 , the gas outlet conduit 42 extending substantially parallel to the diaphragm 34 .

[0112] according to Figure 3a and 3b In the embodiments of the present invention, the center 46 of the diaphragm 34 is offset from the center 48 of the valve seat 32 when viewed perpendicular to the general plane 39 of the diaphragm 34. In these embodiments, the center 46 of the diaphragm 34 is offset from the center 48 of the valve seat 32 toward the gas outlet conduit 42 and the gas outlet 13.

[0113] Thus, the pressure drop in the valve 12 may be reduced compared to a diaphragm that is centered relative to the valve seat.

[0114] Figure 3a The center 46 of the diaphragm 34 and the center 48 of the valve seat 32 are marked with lines. The center 48 of the valve seat 32 can coincide with the center line 41 of the inlet passage 40, as shown in FIG. Figure 3a Displayed in.

[0115] exist Figure 3a 3, the general plane 39 of the diaphragm is indicated as coinciding with the abutment plane 39 of the diaphragm 34. Again, the abutment plane 39 of the diaphragm 34 is the plane 39 of the abutment area 44 of the diaphragm 34 that is configured to abut against the valve seat 32.

[0116] If the valve seat 32 has a generally circular shape, then the abutment area 44 also has a generally circular shape.

[0117] according to Figure 3a and 3b In the embodiment of FIG. 3 , the plane 38 comprising the valve seat 32 and the plane 39 comprising the adjoining region 44 of the diaphragm 34 are arranged at an angle α to each other.

[0118] For example, the plane 39 of the abutment region 44 , ie, the abutment plane 39 , may extend within a range of 0.25 degrees to 10 degrees relative to the plane 38 including the valve seat 32 .

[0119] The arrangement of the two planes 38, 49 at an angle α can prevent vibrations in the diaphragm 34 and / or oscillating closing and opening movements of the diaphragm 34 against the valve seat 32. That is, as the diaphragm 34 moves into abutment with the valve seat 32, the abutment area 44 of the diaphragm 34 will gradually come into contact with the valve seat 32. That is, initially the contact area between the abutment area 44 of the diaphragm 34 and the valve seat 32 will be small, but if the pressure difference across the valve 12 increases, the contact area will also increase until the abutment area 44 of the diaphragm 34 contacts the entire valve seat 32.

[0120] According to alternative embodiments of the valve 12 , it may be provided such that the center 46 of the diaphragm 34 is offset from the center 48 of the valve seat 32 , or such that a plane 39 comprising the plane 38 of the valve seat 32 and the adjoining region 44 of the diaphragm 34 is arranged at an angle α to each other.

[0121] It will be understood that the foregoing describes only various example embodiments, and the present invention is limited only by the appended claims. Those skilled in the art will recognize that the example embodiments may be modified, and that different features of the example embodiments may be combined to create embodiments other than those described herein, without departing from the scope of the present invention as defined by the appended claims.

Claims

1. A crankcase gas separator (2), comprising: a separator housing (4) which delimits at least a portion of the separation space (6), a rotor (8) arranged in the separation space (6), wherein the rotor (8) comprises a separation aid in the form of a stack (26) of separation discs (28), a gas outlet channel (10) from the separation space (6), and a gas pressure regulating valve (12) arranged in fluid communication with the gas outlet passage (10), wherein The gas pressure regulating valve (12) comprises a valve seat (32) and a diaphragm (34), wherein the diaphragm (34) is configured to seal against the valve seat (32) and provide a flow direction for gas from the gas outlet passage (10) through the gas pressure regulating valve (12), and wherein The diaphragm (34) is arranged downstream of the valve seat (32) with respect to the flow direction.

2. The crankcase gas separator (2) according to claim 1, wherein: Viewed perpendicularly to a plane (28) including the valve seat (32), a gas flow area within the valve seat (32) and an area of ​​the diaphragm (34) outside the valve seat (32) may have a ratio in the range of 1:1.25 to 1:

5.

3. The crankcase gas separator (2) according to claim 1 or 2, wherein: The gas outlet channel (10) from the separation space (6) is connected to an inlet channel (40) of the gas pressure regulating valve (12), and wherein the inlet channel (40) opens into the valve seat (32).

4. The crankcase gas separator (2) according to claim 3, wherein: The inlet passage (40) of the gas pressure regulating valve (12) extends substantially perpendicular to a plane (38) including the valve seat (32).

5. The crankcase gas separator (2) according to any one of the preceding claims, wherein: The valve closing movement of the diaphragm (34) is in the direction opposite to the direction in which gas flows into the gas pressure regulating valve (12).

6. The crankcase gas separator (2) according to any one of the preceding claims, wherein: The gas pressure regulating valve (12) comprises a gas outlet conduit (42) downstream of the diaphragm (34), and wherein the gas outlet conduit (42) extends substantially parallel to the diaphragm (34).

7. The crankcase gas separator (2) according to any one of the preceding claims, wherein: The center (46) of the diaphragm (34) is offset from the center (48) of the valve seat (32) when viewed perpendicular to the general plane (39) of the diaphragm (34).

8. The crankcase gas separator (2) according to claims 6 and 7, wherein: The center (46) of the diaphragm (34) is offset from the center (48) of the valve seat (32) toward the gas outlet conduit (42).

9. The crankcase gas separator (2) according to any one of the preceding claims, wherein: A plane (39) including a plane (38) of the valve seat (32) and an abutment region (44) of the diaphragm (34) configured to abut against the valve seat (32) are arranged at an angle (α) to each other.

10. The crankcase gas separator (2) according to any one of the preceding claims, wherein: The gas pressure regulating valve (12) further includes a biasing member (36) arranged to bias the diaphragm (34) in a direction away from the valve seat (32).

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