POSITIVE CRANKCASE VENTILATION (PCV) SYSTEM WITH ONE PCV VALVE

Abstract

Methods and systems for a positive crankcase ventilation (PCV) valve are provided. In one example, the PCV valve comprises a housing, a perforated plate positioned within the housing, and a piston pre-tensioned by a spring and configured to move axially through the perforated plate. Within the PCV valve, several longitudinal ribs extend from an outer surface of the piston along its entire length or along an inner surface of the housing and are configured to restrict a section of the piston with a reduced diameter.

Description

Area The present description generally relates to a positive crankcase ventilation (PCV) system with a PCV valve incorporating ribs designed to reduce noise, vibration, and harshness (NVH) during valve operation. General state of the art Vehicles with internal combustion engines include exhaust systems that capture gases from the engine and ultimately expel them into the surrounding environment. Certain internal combustion engines incorporate positive crankcase ventilation (PCV) systems to vent gases from the crankcase into an intake manifold, thus purging gases from the crankcase and reducing the negative impact on various engine components within the crankcase. PCV valves are used to manage the airflow drawn from the crankcase into the intake system. Brief description The inventors recognized the potential benefit of reducing noise, vibration, and harshness (NVH) that can occur in piston-type PCV valves under certain operating conditions. Specifically, vacuum pulses passing through the valve can cause resonance, generating NVH under certain conditions. To achieve NVH reductions and at least partially overcome other challenges, the inventors developed a PCV valve. In one example, the PCV valve comprises a housing, a perforated plate positioned within the housing, and a spring-loaded piston configured to move axially through the perforated plate. Furthermore, the valve features multiple longitudinal ribs extending from an outer surface of the piston along its entire length, or along an inner surface of the housing, to the perforated plate. These ribs interact with the perforated plate or the piston to reduce off-axis piston movement and, in particular, to decrease the likelihood of piston resonance. In this way, NVH is reduced during valve operation. In one example, the multiple longitudinal ribs can be evenly spaced around a central axis. In particular, in such an example, the multiple longitudinal ribs can include a pair of ribs arranged 180° apart around the central axis. This further reduces the probability of the piston resonating with the perforated plate. It is understood that the foregoing summary is provided to introduce, in simplified form, a selection of concepts that are described in greater detail in the detailed description. It is not intended to identify important or decisive features of the claimed subject matter, the scope of which is defined solely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that remedy any of the disadvantages mentioned above or in any part of this disclosure. Brief description of the drawings Fig. 1 shows a schematic diagram of an internal combustion engine system for a vehicle system. Fig. 2 shows an example of a positive crankcase ventilation (PCV) system. Figs. 3-4 show an example of a PCV valve for a PCV system. Fig. 5 shows another example of a PCV valve. Figs. 6-9 show different views of the PCV valve shown in Figs. 3-4. Detailed description The following description concerns positive crankcase ventilation (PCV) systems with PCV valves that exhibit reduced noise, vibration, and harshness (NVH). Figure 1 shows an example of a vehicle, and Figure 2 shows an example of a PCV system that includes a PCV valve venting leakage gas from a crankcase to an intake system. Figures 3-4 and 6-9 show an example of a PCV valve that includes a piston with fins (e.g., grooves) that reduce cyclic piston movement during valve operation and, in particular, decrease the likelihood of piston resonance, thereby reducing NVH during valve operation. Figure 5 shows another example of a PCV valve with a housing that includes fins extending along an inner surface to a perforated plate. Figure 1 illustrates an exemplary vehicle propulsion system 100 in a vehicle 101. The vehicle propulsion system 100 includes a fuel-burning internal combustion engine 110 and an electric motor 120. As a non-restrictive example, the internal combustion engine 110 is an internal combustion engine (ICE), and the electric motor 120 is an electric motor. The electric motor 120 can be configured to utilize or consume a different energy source than the internal combustion engine 110. For example, the internal combustion engine 110 can consume a liquid fuel (e.g., gasoline) to produce an internal combustion engine output, while the electric motor 120 can consume electrical energy to produce an electric motor output. Thus, the vehicle 101 with the propulsion system 100 can be a hybrid electric vehicle (HEV).In one such example, vehicle 101 includes an electric motor, a traction battery, and the like, as described in more detail in this document. In the hybrid vehicle example, the traction motor and the internal combustion engine can have a variety of suitable architectures, as described in more detail in this document. In other examples, however, the vehicle may be an ICE vehicle. The vehicle drive system 100 can utilize a variety of different operating modes depending on the operating conditions to which it is exposed. Some of these modes can allow the internal combustion engine 110 to be kept in a switched-off state (e.g., set to a shut-off state) in which the combustion of fuel in the internal combustion engine is interrupted. For example, under selected operating conditions, the electric motor 120 can drive the vehicle via the drive wheel 130, as indicated by arrow 122, while the internal combustion engine 110 is switched off. During other operating conditions, the internal combustion engine 110 can be set to a switched-off state (as described above), while the electric motor 120 can be operated to charge the energy storage device 150. For example, the electric motor 120 can receive wheel torque from the drive wheel 130, as indicated by arrow 122, whereby the electric motor can convert the vehicle's kinetic energy into electrical energy for storage in the energy storage device 150, as indicated by arrow 124. This process can be described as regenerative deceleration of the vehicle. Thus, in some embodiments, the electric motor 120 can provide a generator function.In other examples, however, a generator 160 can instead receive a wheel torque from the drive wheel 130, whereby the generator can convert the kinetic energy of the vehicle into electrical energy for storage in the energy storage device 150, as indicated by the arrow 162. Under other operating conditions, the internal combustion engine 110 can be operated by burning fuel received from a fuel system 140, as indicated by arrow 142. For example, the internal combustion engine 110 can be operated to drive the vehicle via the drive wheel 130, as indicated by arrow 112, while the electric motor 120 is switched off. Under other operating conditions, both the internal combustion engine 110 and the electric motor 120 can each be operated to drive the vehicle via the drive wheel 130, as indicated by arrows 112 and 122, respectively. A configuration in which both the internal combustion engine and the electric motor can selectively drive the vehicle can be described as a parallel-type vehicle propulsion system.It should be noted that in some embodiments the electric motor 120 can drive the vehicle via a first set of drive wheels and the internal combustion engine 110 can drive the vehicle via a second set of drive wheels. In other embodiments, the vehicle drive system 100 can be configured as an in-line vehicle drive system in which the internal combustion engine does not directly drive the drive wheels. Instead, the internal combustion engine 110 can be operated to supply power to the electric motor 120, which in turn can drive the vehicle via the drive wheel 130, as indicated by arrow 122. For example, under selected operating conditions, the internal combustion engine 110 can drive the generator 160, as indicated by arrow 116, which in turn can supply electrical energy to one or more of the electric motors 120, as indicated by arrow 114, or to the energy storage device 150, as indicated by arrow 162.As another example, the internal combustion engine 110 can be operated to drive the electric motor 120, which in turn can provide a generator function to convert the internal combustion engine output into electrical energy, with the electrical energy being stored in the energy storage device 150 for later use by the electric motor. The fuel system 140 may include one or more fuel storage tanks 144 for storing fuel on board the vehicle. For example, the fuel tank(s) 144 may store one or more liquid fuels, including, without limitation, gasoline, diesel, and alcoholic fuels. In some examples, the fuel may be stored on board the vehicle as a mixture of two or more different fuels. For example, the fuel tank(s) 144 may be configured to store a mixture of gasoline and ethanol (e.g., E10, E85, etc.) or a mixture of gasoline and methanol (e.g., M10, M85, etc.), with these fuels or fuel mixtures being available for delivery to the internal combustion engine 110, as indicated by arrow 142.Other suitable fuels or fuel mixtures can be supplied to the internal combustion engine 110, which can be burned in the internal combustion engine to produce an internal combustion engine output. The internal combustion engine output can be used to propel the vehicle, as indicated by arrow 112, or to charge the energy storage device 150 via the electric motor 120 and / or the generator 160. The internal combustion engine 110 and the other internal combustion engines described in this document can be configured for compression and / or spark ignition. In some embodiments, the energy storage device 150 can be configured to store electrical energy that can be supplied to other electrical consumers (other than the electric motor) located on board the vehicle, including cabin heating and air conditioning, combustion engine starting, headlights, cabin audio and video systems, etc. As a non-limiting example, the energy storage device 150 can include one or more batteries and / or capacitors. A control system 190 can communicate with one or more of the internal combustion engine 110, the electric motor 120, the fuel system 140, the energy storage device 150, and the generator 160. The control system 190 can receive sensor feedback information from one or more of the internal combustion engine 110, the electric motor 120, the fuel system 140, the energy storage device 150, and the generator 160. Furthermore, in response to this sensor feedback, the control system 190 can send control signals to one or more of the internal combustion engine 110, the electric motor 120, the fuel system 140, the energy storage device 150, and the generator 160. The control system 190 can receive an output request from the vehicle propulsion system by a driver 102.For example, the control system 190 can receive sensory feedback from a pedal position sensor 189, which communicates with a pedal 187. The pedal 191 can schematically refer to a speed reduction pedal and / or a speed setting pedal. The control system 190 includes a controller 191. The controller 191 is shown in Fig. 1 as a conventional microcomputer, which includes: a microprocessor unit 192, input / output ports 193, read-only memory 194 (e.g. persistent memory), random access memory 195, keep-alive memory 196 and a conventional data bus.According to the illustration, the control unit 191 receives various signals from sensors coupled to the internal combustion engine 110, which, in addition to the signals discussed above, include the following: engine coolant temperature (ECT) from a temperature sensor coupled to a cooling sleeve; a position sensor coupled to a driver-activated pedal to detect a force exerted by a human foot; a position sensor coupled to a brake caliper control pedal to detect a force exerted by a foot; a manifold pressure (MAP) measurement from a pressure sensor coupled to the intake manifold; an engine position sensor from a position sensor detecting the crankshaft position; a measurement of the mass of air entering the internal combustion engine from a sensor; and a throttle position measurement from a sensor.Air pressure can also be measured and processed by the control unit 191. A position sensor can generate a predetermined number of evenly spaced pulses with each revolution of the crankshaft, from which the internal combustion engine speed (rpm) can be determined. The control unit 191 can receive various signals from sensors connected to the internal combustion engine 110, including a manifold airflow pressure (MAP) sensor reading; an engine coolant temperature (ECT) reading from the temperature sensor; an exhaust air-fuel ratio reading from the exhaust gas sensor; a crankcase pressure (CKCP) sensor; a pressure boost (BP) sensor; a temperature-intake (TIP) sensor, etc. Furthermore, the control unit can monitor and adjust the position of various actuators based on inputs received from these sensors. These actuators can include, for example, the throttle and intake and exhaust valve systems.A read-only storage medium 194 may contain computer-readable data that represents instructions which can be executed by the processor 192 to carry out the procedures described below, as well as other variants which are assumed and not explicitly listed. During operation, each cylinder within the 110 engine typically goes through a four-stroke cycle; the cycle includes an intake stroke, a compression stroke, a power stroke, and an exhaust stroke. During the intake stroke, the exhaust valve generally closes and the intake valve opens. Air is drawn into the combustion chamber via the intake manifold, and the piston moves toward the bottom of the cylinder to increase the volume within the combustion chamber. The position at which the piston is near the bottom of the cylinder and at the end of its stroke (e.g., when the combustion chamber has reached its maximum volume) is typically referred to by someone skilled in the art as bottom dead center (BDC). During the compression stroke, the intake and exhaust valves are closed. The piston moves toward the cylinder head to compress the air within the combustion chamber. The point at which the piston is closest to the cylinder head at the end of its stroke (e.g., when the combustion chamber has its smallest volume) is generally referred to by those skilled in the art as top dead center (TDC). In a process referred to below as injection, fuel is introduced into the combustion chamber. In a process referred to below as ignition, the injected fuel is ignited by known ignition devices such as a spark plug and / or compression ignition, resulting in combustion. During the power stroke, the expanding gases push the piston back to bottom dead center (BDC). The crankshaft converts the piston movement into torque at the crankshaft. Finally, during the exhaust stroke, the exhaust valve opens to release the burnt air-fuel mixture into the exhaust manifold, and the piston returns to top dead center (TDC). It should be noted that the above is shown only as an example and that the timing of the opening and / or closing of the intake and exhaust valves can vary, for example, to provide positive or negative valve overlap, late intake valve closing, or various other effects. The energy storage device 150 can regularly receive electrical energy from a power source 180 located outside the vehicle (which, for example, is not part of the vehicle), as indicated by arrow 184. As a non-restrictive example, the vehicle drive system 100 can be configured as a plug-in HEV, allowing electrical energy to be supplied from the power source 180 to the energy storage device 150 via an electrical power transmission cable 182. During a charging process of the energy storage device 150 from the power source 180, the electrical transmission cable 182 can electrically couple the energy storage device 150 and the power source 180. While the vehicle drive system 100 is operating to propel the vehicle, the electrical transmission cable 182 between the power source 180 and the energy storage device 150 can be disconnected.The control system 190 can identify and / or control the amount of electrical energy stored in the energy storage device, which can be referred to as the state of charge (SOC). In other embodiments, the electrical transmission cable 182 can be omitted, and electrical energy from the power source 180 can be received wirelessly by the energy storage device 150. For example, the energy storage device 150 can receive electrical energy from the power source 180 via one or more methods of electromagnetic induction, radio waves, and electromagnetic resonance. It is understood that any suitable approach can be used to charge the energy storage device 150 from a power source that is not part of the vehicle, such as solar or wind power.In this way, the electric motor 120 can power the vehicle by using a different energy source than the fuel used by the internal combustion engine 110. The fuel system 140 can regularly receive fuel from a fuel source located outside the vehicle. As a non-limiting example, the vehicle propulsion system 100 can be refueled by receiving fuel via a fuel delivery device 170, as indicated by an arrow 172. In some embodiments, the fuel tank 144 can be configured to store the fuel received from the fuel delivery device 170 until it is supplied to the internal combustion engine 110 for combustion. In some embodiments, the control system 190 can receive an indication of the fuel level stored in the fuel tank 144 via a fuel level sensor. The fuel level stored in the fuel tank 144 (such as...)(identified by the fuel level sensor) can be communicated to the driver 102, for example, via a fuel gauge or a display on a vehicle instrument panel 197. The vehicle propulsion system 100 may also include an ambient temperature / humidity sensor 198 and the like. The vehicle instrument panel 197 may include indicator light(s) and / or a text-based display that shows messages to an operator. The vehicle dashboard 197 may also include various input sections for receiving operator input, such as buttons, touchscreens, voice input / recognition, etc. The internal combustion engine 110 shown in Fig. 1 can be a turbocharged internal combustion engine, which includes a turbocharger with a compressor and an exhaust gas turbine. Alternatively, the internal combustion engine 110 can be self-priming. With reference to Fig. 2, this figure shows an exemplary system configuration for an internal combustion engine 200, which may be included in a motor vehicle drive system. In one example, the internal combustion engine 200 may be an example of the internal combustion engine 110 from Fig. 1 in the vehicle drive system 100 from Fig. 1. As shown in Fig. 2, the internal combustion engine 200 may include at least one cylinder 202 formed by a cylinder head 204 and a cylinder block 206 therein. The cylinder block 206 may include a crankcase 208 containing an oil reservoir 210 (e.g., an oil pan) with oil in it, and a crankshaft 212 coupled to a piston 214. Cam covers 216 and 220 may be coupled to the cylinder head 204. A PCV system 218 can also be incorporated more generally into the internal combustion engine 200 and / or the vehicle. In one example, the PCV system 218 can include an oil separator (e.g., a partial-load (traction) oil separator) that is integrated into or coupled to the cam cover 216. The oil separator can be in fluid communication with the crankcase 208 and is configured to remove oil (e.g., oil droplets) from the gases flowing through it and can return the oil to the oil reservoir 210. The PCV system 218 further includes a PCV valve 222, which is in fluid communication with an intake manifold 224 via a PCV line 226 (e.g., a PCV channel). In the illustrated example, the PCV valve 222 is coupled to the cam cover 216. However, other PCV valve positions are also possible. The PCV valve 222 controls the flow rate of gases through it. The adjustment of the gas flow rate can depend on the intake manifold vacuum. An example of a PCV valve is shown in Fig. 3-4 and is discussed in more detail in this document. As illustrated in Fig. 2, the intake manifold 224 is included in an intake system 228, which supplies gas to the cylinder 202 via an intake valve 272. A throttle 230 may also be included in the intake system 228, which controls the gas flow to the cylinder 202. A compressor 232 (which may be included in a turbocharger or a supercharger) may also be included in the intake system 228. In other examples, however, the internal combustion engine may be configured as a self-priming engine. The intake system 228 may further include an air filter 234 in an intake duct 236 upstream of the throttle 230 and, in the case of a turbocharged internal combustion engine, the compressor 232. It is understood that the PCV system 218 may include additional components, such as another oil separator in the cam cover 220, valves in the cam covers that divert oil around the separators, combinations thereof, and the like. Furthermore, an exhaust valve 273 is coupled to the cylinder and allows exhaust gas from the cylinder 202 to flow to an exhaust system. The engine 200 can be configured to implement a four-stroke combustion cycle, such as the combustion cycle discussed above with reference to Fig. 1. The internal combustion engine 200 can be controlled at least partially by a control system, such as a control system with a controller (e.g. the control system 190 and the controller 191 shown in Fig. 1). Fig. 2 illustrates the general flow pattern in the PCV system 218 during a lower load condition (e.g., part load) / uncharged operating condition. Arrows 275 indicate in particular the general flow direction of crankcase gases and arrows 276 indicate the general direction of intake air. As shown, crankcase gases flow from the crankcase to the camshaft, into the PCV line 226, and then into the intake manifold 224. Conversely, fresh air flows from the intake manifold 236 via the PCV line 240 to the camshaft cover 220. From the camshaft cover, fresh air flows into the crankcase 208. Furthermore, oil can flow from the cylinder head 204 to the cylinder block 206 and then to the oil reservoir 210 in the crankcase 208. Thus, oil can move past the piston ring(s) in the internal combustion engine. An axis system is provided in Fig. 2 and Figs. 3-4 for reference. In one example, the z-axis can be a vertical axis (e.g., parallel to a gravitational axis), the x-axis can be a longitudinal axis (e.g., a horizontal axis), and / or the y-axis can be a lateral axis. In other examples, however, the axes may have different orientations. Figures 3-4 show an example of a PCV valve 300. It is understood that the PCV valve 300 serves as an example of the PCV valve 222 shown in Figure 2. The PCV valve 300 shown in Figures 3-4 comprises a housing 302 with a perforated plate 304 arranged in an interior 306 of the housing. In the illustrated example, the perforated plate 304 is constructed separately from the housing 302. However, in other examples, the housing and the perforated plate may be constructed as a single component. Furthermore, in the illustrated example, the perforated plate 304 is arranged in a recess 308 in an inner surface 310 of the housing 302. In this way, axial movement of the hole is restricted. The perforated plate 304 also includes a central hole 311 through which crankcase gases flow during valve operation. The PCV valve 300 further includes a piston 312, which is arranged in the housing 302. A spring 314 also biases the piston 312 within the valve. Specifically, the spring 314 is positioned circumferentially outwards from the piston 312. In the illustrated example, the spring 314 is a coil spring. However, other suitable types of springs can be used in the PCV valve in other examples. The piston 312 moves up and down along a central axis 344 to open and close the valve. Furthermore, in the illustrated example, the housing 302 includes several flanges 316. For clarification, the housing 302 includes an upper flange 318 and a lower flange 320. However, the housing can be designed with alternative structural features. For example, in other examples, one or both of the flanges can be omitted from the housing. A seal 322 can be arranged in a recess 324 in an outer surface 326 of the housing 302. The seal 322 enables the PCV valve 300, for example, to be attached to the crankcase in a sealing manner. In the illustrated example, the piston 312 comprises a reduced-diameter section 328, a body 330, and a base 332. More precisely, the reduced-diameter section 328 has a diameter 334 that is smaller than the diameter 336 of the body 330. Furthermore, the base 332 has a diameter 338 that is larger than the diameter 336 of the body 330. The reduced-diameter section 328 can have a constant diameter along its axial length. Likewise, the body 330 can have a constant diameter along its axial length. A tapered section 340 of the piston 312 can be arranged between the reduced-diameter section 328 and the body 330. During valve operation, the piston 312 moves up and down along the axis 344 as previously described.In a closed position, the tapered section 340 of the piston seals against the perforated plate 304. Conversely, in an open position, the tapered section 340 of the piston moves away from the perforated plate 304 to allow crankcase gas to flow through it. The piston 312 further incorporates ribs 342 which interact with the perforated plate 304 to reduce the tilting movement of the piston 312 away from a central axis 344. More precisely, during PCV valve operation, the piston 312 moves along the central axis 344 based on crankcase pressure and intake manifold pressure. However, the ribs 342 restrict the piston 312 from moving into an off-axis position with respect to the central axis 344. In particular, the ribs 342 can form a sliding-fit interface 346 with a surface 348 of the perforated plate 304. The ribs 342 extend longitudinally from an upper end 347 of the piston 312 to a lower end 357 of the piston body 330. "Longitudinally" in this case refers to a direction parallel to the axis 344. This increases the stability of the piston 312 as it moves between an open and a closed position, thereby reducing the likelihood of NVH during valve operation. Each of the ribs 342 can have an inner surface 360 ​​and lateral surfaces 362 extending from the inner surface to the body 330 and the reduced-diameter section 328. These surfaces can be planar in one example. However, the inner surface 360 ​​can be curved to conform to the curvature of the perforated plate surface 348, and the lateral surfaces 362 can be planar. The ribs 342 can be evenly spaced around the central axis 344 on the piston 312. More precisely, the ribs 342 can include a set of ribs 349 with ribs 350 and 351, which are arranged 180° apart from each other around the central axis 344. Furthermore, in the illustrated example, another set of ribs 352, comprising ribs 353 and 354, is included in the piston, and they are arranged 180° apart from each other around the central axis 344. In particular, the ribs 342 in the illustrated example are separated by 90° around the axis 344. However, in other examples, other suitable arrangements of the ribs in the piston can be used. In one example, the ribs 342 can be formed integrally within the piston 312. In other examples, however, the ribs 342 can be welded, bonded, or otherwise attached to the piston 312. Furthermore, the ribs 342 and the piston 312 can be constructed from suitable materials, such as one or more metals, polymers, and the like. The PCV valve 300, shown in Fig. 3-4, further includes a lower plate 370 with a central opening 372 to allow crankcase gases to flow through it. The lower plate 370 fits into an interior of the housing 302. Fig. 5 shows another example of a PCV valve 500. The PCV valve 500 again comprises a housing 502, a piston 504, a spring 506, a perforated plate 508, and a bottom plate 510. The piston 504 again comprises a base 512, a body 514, and a reduced-diameter section 516. However, the piston 504 shown in Fig. 5 does not include any ribs in the illustrated example. On the other hand, the housing 502 includes the ribs 518. More precisely, the ribs 518 are configured to interact with the reduced-diameter section 516 of the piston 504 to reduce off-axis movement of the piston during valve operation, thereby reducing NVH (noise, vibration, and harshness). Specifically, ribs 518 include a first set of ribs 520 and 522 and a second set of ribs 524 and 526.More precisely, in the illustrated example, ribs 520 and 522 in the first set of ribs are separated by 180° with respect to a central axis 550. Similarly, ribs 524 and 526 in the second set of ribs are separated by 180° with respect to a central axis 550 in the illustrated example. However, other rib positions may be used in other examples. Furthermore, in other examples, the housing may contain only one pair of ribs or more than two pairs of ribs. The upper sides 528 or the ribs 518 are positioned below an upper opening 530 in the housing 502. Furthermore, the ribs 518 can be positioned above the perforated plate 508 with a gap 532 between them. A seal 534 is again positioned in an outer recess of the housing 502. As piston 504 moves upwards, section 516, with its reduced piston diameter, engages with ribs 520, 522, 524, and 526. This reduces the off-axis movement of piston 504, thereby reducing NVH (noise, vibration, and harshness). Fig. 6 shows an exploded view of the PCV valve 300. The housing 302, the perforated plate 304, the piston 312, the spring 314, and the lower plate 370 are shown again. The ribs 342 in the piston 312 are also shown in Fig. 6. In addition, the reduced-diameter section 328, the body 330, and the base 332 of the piston 312 are further illustrated in Fig. 6. Fig. 7 shows another assembled cross-sectional view of the PCV valve 300. The housing 302, the perforated plate 304, the piston 312, the spring 314, and the lower plate 370 are shown again. In the illustrated example, the base 332 of the piston 312 contacts the lower plate 370. Fig. 8 shows a top view of the PCV valve 300. The ribs 342 of the piston 312 contact an inner surface 800 of the perforated plate 304, as shown. In this way, the movement of the piston off-axis is restricted, thereby reducing NVH during valve operation. Fig. 9 shows a detailed view of the piston 312. The ribs 342 in the piston 312 are also shown. In addition, the reduced-diameter section 328, the body 330, and the base 332 of the piston 312 are further illustrated in Fig. 9. Figures 3-9 are shown approximately to scale. In alternative embodiments, however, the components may have different relative dimensions. Figures 1-9 show exemplary configurations with a relative positioning of the various components. If such elements are shown to be in direct contact or directly coupled to one another, they may be described as directly contacting or directly coupled, at least in one example, unless otherwise noted. Likewise, elements shown to be connected or adjacent to one another may be described as connected or adjacent, at least in one example. For example, components that are in surface-dividing contact with one another may be described as being in surface-dividing contact. Another example is that elements positioned separately from one another, with only a gap between them and no other components, may be described as such, at least in one example.As another example, elements shown above / below each other, on opposite sides, or to the left / right of each other can be described in this way relative to one another. Furthermore, as shown in the figures, a topmost element or the highest point of an element can be referred to as the "top" of the component in at least one example, and a bottommost element or the lowest point of the element can be referred to as the "bottom" of the component. In the sense used here, top / bottom, upper / lower, and above / below can refer to a vertical axis of the figures and be used to describe the arrangement of elements of the figures in relation to one another. Thus, in one example, elements shown above other elements are positioned vertically above the other elements.As another example, the shapes of elements depicted within the figures can be described as having these shapes (such as circular, straight, planar, curved, rounded, beveled, angled, or the like). Furthermore, elements shown intersecting each other can, in at least one example, be described as intersecting elements or as intersecting each other. Even further, an element shown within another element or shown outside another element can, in one example, be described as such. In one embodiment, a positive crankcase ventilation (PCV) valve is provided, comprising a housing; a perforated plate positioned within the housing; and a piston that is spring-loaded and configured to move axially through the perforated plate, with multiple longitudinal ribs extending from an outer surface of the piston along its entire length. In one example, the multiple longitudinal ribs may be uniformly spaced about a central axis. Furthermore, in another example, the multiple longitudinal ribs may include a pair of ribs arranged about the central axis 180° apart from each other. In yet another example, the multiple longitudinal ribs may include two pairs of ribs, each pair arranged about the central axis 180° apart from each other.In another example, the piston may include an upper section with a reduced diameter and a body. In another example, the piston may include a base positioned beneath the body. In yet another example, the PCV valve may further include a seal located in a recess in the housing. The spring may be a coil spring in yet another example. In another example, the multiple longitudinal ribs may be integrally formed with the housing. In another embodiment, a positive crankcase ventilation (PCV) system is provided in an internal combustion engine, comprising a PCV valve including: a housing; a perforated plate positioned within the housing; a spring axially constrained by the perforated plate; and a piston biased by the spring and configured to move axially through the perforated plate, with multiple longitudinal ribs extending from an outer surface of the piston along its entire length. In one example, the multiple longitudinal ribs may include a first pair of ribs. In another example, the first pair of ribs may be arranged 180° apart from each other around a central axis. In yet another example, the multiple longitudinal ribs may include a second pair of ribs.In another example, the first pair of ribs can be arranged 180° apart around a central axis. In another example, the piston can include a reduced-diameter upper section and a body; and the piston can include a base positioned beneath the body. In one example, the internal combustion engine can be a turbocharged engine. In yet another example, the internal combustion engine can be a naturally aspirated engine. In another example, the multiple longitudinal ribs can be formed integrally with the casing. In another illustration, a valve is provided in a positive crankcase ventilation (PCV) system comprising an axially movable piston with grooves forming a sliding fit interface with a perforated plate. It should be noted that the exemplary control and estimation routines contained in this document can be used with various internal combustion engine and / or vehicle system configurations. The control procedures and routines disclosed in this document can be stored as executable instructions in non-transitory memory and can be executed by the control system, in combination with the various sensors, actuators, and other engine hardware. The specific routines described in this document can represent one or more of any number of processing strategies, such as event-driven, interrupt-driven, multitasking, multithreading, and the like. Accordingly, various illustrated actions, operations, and / or functions can be performed in the illustrated sequence or in parallel, or in some cases, omitted.Likewise, the processing sequence is not strictly necessary to achieve the features and advantages of the exemplary embodiments described in this document, but is provided for the sake of clarity and description. One or more of the illustrated actions, processes, and / or functions can be performed repeatedly, depending on the specific strategy employed. Furthermore, the described actions, processes, and / or functions can graphically represent code to be programmed into non-transient memory of the computer-readable storage medium in the engine control system, with the described actions being executed by carrying out the instructions in a system that includes the various engine hardware components in combination with the electronic control unit. It is understood that the configurations and routines disclosed in this document are exemplary and that these specific embodiments are not to be interpreted in a limiting sense, as numerous variations are possible. For example, the foregoing technology can be applied to V6, I4, I6, V12, 4-cylinder boxer, and other engine types. Furthermore, unless expressly stated otherwise, the terms "first," "second," "third," and the like are not intended to denote any order, position, quantity, or significance, but are used merely to distinguish one element from another. The subject matter of this disclosure includes all novel and non-obvious combinations and subcombinations of the various systems and configurations, as well as other features, functions, and / or properties disclosed herein. In the present context, the term "approximately" is meant to mean plus or minus five percent of the range, unless otherwise specified. The following claims highlight specific combinations and subcombinations that are considered novel and not obvious. These claims may refer to "one" element, "a first" element, or the equivalent thereof. Such claims are to be understood as including one or more such elements and neither requiring nor excluding two or more such elements. Other combinations and subcombinations of the disclosed features, functions, elements, and / or properties may be claimed by amending the present claims or by filing new claims in this or a related application.Such patent claims, regardless of whether they have a broader, narrower, the same or different scope compared to the original patent claims, are also considered to be included in the subject matter of the present disclosure. According to the present invention, a positive crankcase ventilation (PCV) valve is provided, comprising: a housing; a perforated plate positioned within the housing; and a piston that is spring-loaded and configured to move axially through the perforated plate; wherein the housing or the piston includes several longitudinal ribs extending along an outer surface of the piston or an inner surface of the housing to the perforated plate. According to one embodiment, the multiple longitudinal ribs are uniformly spaced around a central axis. According to one embodiment, the multiple longitudinal ribs include a pair of ribs arranged 180° apart around the central axis. According to one embodiment, the multiple longitudinal ribs include a pair of ribs arranged 180° apart from each other around a central axis. According to one embodiment, the piston includes an upper section with a reduced diameter and a body. According to one embodiment, the piston includes a base that is positioned below the body. According to one embodiment, the invention is further characterized by a seal which is arranged in a recess in the housing. According to one embodiment, the spring is a coil spring. According to one embodiment, the multiple longitudinal ribs form a sliding-fit interface with the perforated plate. According to one embodiment, the multiple longitudinal ribs are formed integrally with the housing. According to the present invention, a positive crankcase ventilation (PCV) system is provided in an internal combustion engine, comprising: a PCV valve comprising: a housing; a perforated plate positioned within the housing; a spring axially constrained by the perforated plate; and a piston biased by the spring and configured to move axially through the perforated plate, wherein several longitudinal ribs extend along: an outer surface of the piston along the entire length of the piston; or along an inner surface of the housing to the perforated plate and configured to constrain According to one embodiment, the multiple longitudinal ribs include a first pair of ribs. According to one embodiment, the first pair of ribs is arranged 180° apart from each other around a central axis. According to one embodiment, the multiple longitudinal ribs include a second pair of ribs. According to one embodiment, the first pair of ribs is arranged 180° apart from each other around a central axis. According to one embodiment: the piston includes an upper section with a reduced diameter and a body; and the piston includes a base that is positioned below the body. According to one embodiment, the internal combustion engine is a turbocharged internal combustion engine. According to one embodiment, the internal combustion engine is a self-priming internal combustion engine. According to one embodiment, the multiple longitudinal ribs form a sliding-fit interface with the perforated plate. According to one embodiment, the multiple longitudinal ribs are formed integrally with the housing.

Claims

Positive crankcase ventilation (PCV) valve, comprising: a housing; a perforated plate positioned within the housing; and a piston pre-tensioned by a spring and configured to move axially through the perforated plate; wherein the housing or the piston includes several longitudinal ribs extending along an outer surface of the piston or an inner surface of the housing to the perforated plate. PCV valve according to claim 1, wherein the multiple longitudinal ribs are evenly spaced around a central axis. PCV valve according to claim 2, wherein the multiple longitudinal ribs comprise a pair of ribs arranged 180° apart from each other around the central axis. PCV valve according to claim 1, wherein the multiple longitudinal ribs comprise two pairs of ribs, each arranged 180° apart from the other around a central axis. PCV valve according to claim 1, wherein the piston includes an upper section with a reduced diameter and a body. PCV valve according to claim 5, wherein the piston includes a base positioned below the body. PCV valve according to claim 1, further comprising a seal arranged in a recess in the housing. PCV valve according to claim 1, wherein the spring is a coil spring. PCV valve according to claim 1, wherein the multiple longitudinal ribs form a sliding fit interface with the perforated plate. PCV valve according to claim 1, wherein the multiple longitudinal ribs are formed integrally with the housing. PCV valve according to claim 3, wherein the multiple longitudinal ribs include a second pair of ribs. PCV valve according to claim 11, wherein the second pair of ribs is arranged 180° apart from each other around the central axis. PCV valve according to claim 1, wherein: the piston includes an upper section with a reduced diameter and a body; and the piston includes a base positioned below the body. PCV valve according to claim 1, wherein the PCV valve is included in a turbocharged internal combustion engine. PCV valve according to claim 1, wherein the PCV valve is included in a self-priming internal combustion engine.

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