JP2005146972A - Breather equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a breather device capable of surely discharging oil when the oil separated and removed from blow-by gas is reserved once. <P>SOLUTION: The breather device 1 is provided with an oil separator 2 and an oil reservoir tank 6 provided below the oil separator 2. An oil discharge opening 61 for oil L is formed on a bottom wall of the oil reservoir tank 6 and a check valve 7 is provided at an outer part. The check valve 7 closes the oil discharge opening 61 by negative pressure when an internal combustion engine 101 is operated and is forcibly driven to open the oil discharge opening 61 when the internal combustion engine 101 stops, by a link mechanism 8 having a pressure receiving surface 84a formed and having a pressure receiving plate 84 and a coil spring 85 provided. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a breather device that performs gas-liquid separation of blow-by gas.

  In general, blowby gas leaking into a crankcase from between a piston and a cylinder in a compression process or an expansion process of an internal combustion engine is mixed with mist-like oil particles to become oil mist. As described above, the blow-by gas containing the oil component and the gas component is usually subjected to gas-liquid separation, and then the oil component is recovered and the gas component is reduced to the internal combustion engine side. At this time, if the gas-liquid separation is insufficient, the oil consumption increases, so various gas-liquid separation structures or devices such as an oil separator and a breather device have been proposed.

  As an example of such a gas-liquid separation structure or apparatus, Patent Document 1 describes a blow-by gas separator that includes a separation chamber and a valve mechanism provided below the separation chamber. The valve mechanism has an inlet on the separation chamber side and an outlet on the oil drop passage side, and a first valve body and a second valve body are disposed between the inlet and the outlet, respectively. Both valve bodies are interlocked according to the pressure difference between the chamber and the oil dropping passage, and the other valve body is configured to open when one valve body is closed.

In this conventional apparatus, the interlocking valve body is pulled up to the separation chamber side by the negative pressure in the separation chamber, and conversely, when the separation chamber becomes positive pressure, the positive pressure, the weight of the valve body and the oil It is pulled down to the oil drop passage by weight. Thus, it is intended to reliably return the oil temporarily accumulated in the separator to the crank chamber side through the oil dropping passage without flowing back to the intake manifold side.
JP 2003-13723 A

  However, if a valve mechanism that drains oil by opening and closing the valve body is used, the oil around the valve body or attached to the valve body will deteriorate over time and its viscosity will increase. There is a risk of sticking to the member. In the above-described conventional device, it is considered that the valve body tends to stick, particularly when the valve body is pulled down by its own weight. At this time, if the valve body is firmly fixed, the conventional separator uses a pressure difference between the separation chamber and the oil dropping passage as power for opening and closing the valve body, so that a sufficient driving force cannot be realized, A state in which the valve body does not operate may occur.

  If this happens, oil will not be discharged from the separator, and depending on the relationship between the magnitude of negative pressure on the intake side and the amount of oil accumulated in the separator, a large amount of oil will flow into the internal combustion engine such as the engine at once through the blow-by gas passage. There is a risk that. In this case, the engine performance is reduced due to the impact at that time, and in some cases, engine peripheral parts such as the engine and the intake system are damaged.

  Therefore, the present invention has been made in view of such circumstances, and when the oil component separated and removed from the blow-by gas is once stored, the oil component can be reliably discharged, whereby the oil component can be discharged into the internal combustion engine. It aims at providing the breather apparatus which can prevent flowing in at a stretch.

  In order to solve the above problems, a breather device according to the present invention is connected to an internal combustion engine, is supplied with blow-by gas containing an oil component and a gas component, and a gas-liquid separation unit that performs gas-liquid separation of the blow-by gas And an oil holding part in which the oil component separated from the blow-by gas is stored and a discharge port for the oil is provided, a valve body, and And an opening / closing mechanism having a drive unit that is connected to the valve body and drives the valve body so as to open / close the discharge port according to the state of the internal combustion engine.

  In the breather device configured as described above, blow-by gas generated by the operation of the internal combustion engine is introduced into the gas-liquid separator, and the oil component and the gas component are separated from each other. The gas component is usually returned to the intake system of the internal combustion engine in which the breather device is installed, while the oil component is sent to the oil holding unit connected to the gas-liquid separation unit. When the discharge port provided in the oil holding part is closed by the valve body, the oil content is temporarily stored in the oil holding part, and when the discharge port is opened by the valve body, the stored oil content is stored. Is discharged to the outside of the oil holding portion and finally returned to the internal combustion engine side.

  At this time, the opening and closing of the valve body is forcibly performed according to the state of the internal combustion engine by the drive unit of the opening and closing mechanism, so even if the valve body is stuck, the sticking is canceled and the valve body is opened. Can be moved. In this case, if the driving force of the valve body by the drive unit exceeds the assumed fixing force of the valve body, the sticking of the valve body is more reliably prevented. Accordingly, it is possible to prevent the amount of oil that exceeds the allowable value from being accumulated in the oil holding portion. As a result, even if an excessive intake system negative pressure is applied, a sudden and large amount of oil is prevented from flowing back to the internal combustion engine side through the gas-liquid separator.

  In addition, when the internal combustion engine is in an operating state, the open / close mechanism is provided with an oil holding portion when the internal combustion engine is in operation to prevent backflow of oil from the oil recovery system due to negative pressure on the intake system. It is preferable that the exhaust port is closed, and when the internal combustion engine is stopped, the exhaust port is opened to discharge the oil stored in the oil holding portion to the outside.

  More specifically, the opening / closing mechanism is applied with a first force that moves the valve body so that the discharge port is closed or a second force that moves the valve body so that the discharge port is opened. Therefore, it is useful to have a surface formed so as to interlock with the valve body. If it does in this way, the 1st force or the 2nd force will be transmitted to a valve element via the surface, and the opening and closing operation of an outlet will be performed.

  Further, in relation to the state of the internal combustion engine, the opening / closing mechanism is configured such that the first force is applied to the surface when the internal combustion engine is operated and the second force is applied when the internal combustion engine is stopped. More preferably, the above force is applied to the surface.

  Examples of the first force applied to the surface include pressure generated in the intake system connected to the internal combustion engine. In this case, strictly speaking, the first force is a value obtained by multiplying the pressure by the effective area of the surface, and may be considered as a vector amount or a scalar amount. Specifically, for example, a valve body is provided outside the oil holding portion, a member connected to the valve body and having a pressure receiving surface is sealed in a certain space, and the space is divided into a plurality of spaces. Preferably, one space region is communicated with an appropriate negative pressure generating portion such as an intake system, for example, an intake manifold, and the pressure receiving surface is biased toward the other space side.

  The valve body is separated from the discharge port in such a state that the pressure receiving surface is urged as such, and when the negative pressure is applied to the pressure receiving surface and sucked, the valve body covers the discharge port. It is preferable to provide a movable mechanism (link mechanism) that comes into contact with the frame. Examples of the means for urging the pressure receiving surface include elastic bodies such as various springs installed so as to press the pressure receiving surface, and the pressing force acts on the pressure receiving surface as a second force.

  With this configuration, when the internal combustion engine is in an operating state, the negative pressure generated at the negative pressure generation site such as the intake manifold is applied to the pressure receiving surface. When the tensile force (attraction force) due to the negative pressure exceeds the pressing force acting in the opposite direction by a spring or the like, the member on which the pressure receiving surface is formed moves to the negative pressure side, and the valve body connected thereto moves to the outlet port. It drives so that it may contact | abut to the circumference | surroundings, and, thereby, the state which the discharge port was closed is maintained.

  On the contrary, when the internal combustion engine is in a stopped state, the inside of the negative pressure generating part such as the intake manifold is at atmospheric pressure, and the pressure receiving surface is applied with a pressing force by a spring or the like to move to the opposite side of the negative pressure generating part. Then, the valve body connected thereto is driven away from the discharge port, and the state where the discharge port is opened is maintained. Thus, the forced opening and closing of the discharge port is realized with a simple mechanism.

  According to the breather device of the present invention, it is possible to reliably prevent sticking of the valve body that opens and closes the discharge port provided in the oil holding portion in which the oil component separated and removed from the blow-by gas is temporarily stored. Oil can be prevented from accumulating in the oil holding part. In addition, it is possible to reliably prevent the oil component from flowing into the internal combustion engine at once, and to eliminate the possibility that the internal combustion engine and its peripheral parts are damaged.

  Hereinafter, embodiments of the present invention will be described in detail. The positional relationship such as up, down, left, and right is based on the positional relationship shown in the drawings unless otherwise specified. Further, the dimensional ratios in the drawings are not limited to the illustrated ratios.

  FIG. 1 is a diagram showing a configuration and a cross-sectional view of a main part of a preferred embodiment of a breather apparatus according to the present invention. The breather apparatus 1 constitutes a PCV (Positive Crankcase Ventilation) system connected to an internal combustion engine 101, an intake system 102, and an oil recovery system 103 provided in a vehicle, moving equipment, or the like (not shown).

  In the breather device 1, an oil separator 2 (gas-liquid separation unit) is connected to a rear stage of a pre-separator (not shown) connected to, for example, a crankcase (not shown) of the internal combustion engine 101 via a pipe P1, and further below that. The oil holding tank 6 (oil holding part) is provided. The oil separator 2 is a cyclone separator, and includes a barrel portion 211 and a reverse cone portion 212 having a reverse cup shape, and an oil discharge pipe 213 is joined to the lower end of the reverse cone portion 212.

  A gas supply pipe 3 extending from the pipe P <b> 1 is connected to the gas inlet 3 a provided on the side wall of the trunk portion 211. In addition, a gas discharge pipe 4 through which the blow-by gas from which the oil component has been separated and discharged is extended and extended from the pipe P2 is installed through the upper wall of the body 211.

  The oil holding tank 6 has an oil introduction port 2a formed in the upper wall of a container having a constant space volume and having an oil discharge port 61 (discharge port) provided on the bottom wall. The lower end of the oil discharge pipe 213 of the oil separator 2 is joined to the oil introduction port 2a. In addition, one end of an oil discharge portion 70 that is connected to the oil recovery system 103 via the pipe P3 and has a tubular shape is joined to the outer periphery of the oil discharge port 61. Furthermore, a check valve 7 (valve element) that has an area that can cover the entire oil discharge port 61 and is movable is provided inside the oil discharge portion 70.

  The check valve 7 is connected to the link mechanism 8 connected to the negative pressure adjusting unit 105 via the pipe 9. The negative pressure adjustment unit 105 is provided so as to communicate with, for example, an intake manifold (not shown) of the internal combustion engine 101 via the pipe P5. The negative pressure adjustment unit 105 is connected to a monitor unit 104 that monitors the state of the internal combustion engine 101 and / or conditions during operation. The monitor unit 104 is preferably provided as one of control functions in a control unit such as an internal combustion engine mounted on a vehicle or the like.

  The link mechanism 8 has a connecting portion in which the connecting tools 81, 82, 83 are connected in this order and a pressure receiving portion accommodated in the housing 86. The connector 81 is arranged so as to have a cross-sectional pattern and extend in a substantially vertical direction, and an upper end portion thereof is pivotally coupled to a substantially central portion of the lower surface of the check valve 7 and a lower end portion thereof. Is pivotally coupled to one end of the connector 82. The connecting tool 82 has a substantially U-shaped cross section, and is pivotally coupled to the fixed support member 90 at the bent portion.

  Further, the connector 83 is arranged so as to have a cross-sectional pattern and extend in a substantially horizontal direction, and one end thereof is pivotally joined to the other end of the connector 82. Furthermore, the other end of the connector 83 is coupled to the substantially central portion of the pressure receiving plate 84 provided in the housing 86.

  The pressure receiving plate 84 is a substantially flat plate member, and the end wall of the peripheral edge is slidably in contact with the inner wall of the housing 86 over the entire circumference. Thereby, space regions Kb and Kf are defined inside the housing 86. A winding spring 85 is disposed between a surface 84 a of the pressure receiving plate 84 to which the coupling tool 83 is not coupled (hereinafter referred to as “pressure receiving surface 84 a”) and the inner wall of the housing 86. Both end portions of the winding spring 85 are in contact with the pressure receiving surface 84a and the inner wall surface of the housing 86 facing the pressure receiving surface 84a. Further, a through hole 9a is provided in the peripheral wall of the casing 86 with which the winding spring 85 abuts, and the pipe 9 connected to the negative pressure adjusting unit 105 described above is joined to the through hole 9a. .

  In the breather device 1 configured as described above, a blow-by gas that is a gas-liquid mixture of oil particles (oil component) and combustion gas (gas component) is first supplied to a pre-separator (not shown), Among the contained oil particles, those having a relatively large diameter are separated and removed. Next, the blow-by gas is supplied into the body portion 211 of the oil separator 2 along the tangential direction. Thus, the oil separator 2 functions as a tangential inflow type cyclone separator.

  The flow of blow-by gas introduced into the oil separator 2 changes from a linear flow to a vortex flow in the body 211, and descends spirally while rotating along the inner wall of the body 211. Then, when it reaches the reverse cone part 212, it further descends while increasing the rotation speed, reversely rises in the vicinity of the lower end of the reverse cone part 212, and rises while rotating the substantial center part of the body part 211.

  At this time, relatively fine oil particles that have not been separated and removed from the blow-by gas obtain a centrifugal force by the swivel motion, move in the horizontal direction toward the inner wall of the body 211, and collide with the inner wall to lose the momentum. . The oil particles are collected while sequentially flowing down the inner walls of the body portion 211 and the inverted conical portion 212, and are dropped from the lower end of the oil discharge pipe 213 into the oil holding tank 6 through the oil introduction port 2a.

  Thus, the gas-liquid separation of the blow-by gas is performed, and the gas rising in the body 211 of the oil separator 2 becomes a clarified gas from which the oil has been separated, and is sucked into the gas discharge pipe 4 from the lower end 4a of the gas discharge pipe 4 Then, it is sent to the intake system 102 through the pipe P2.

  On the other hand, the oil L dropped in the oil holding tank 6 is temporarily stored in the oil holding tank 6 and discharged from there depending on the state of the internal combustion engine 101. In the present embodiment, the operation state of the check valve 7 is different depending on whether the internal combustion engine 101 is in the operating state or the stopped state as the state of the internal combustion engine 101.

  First, when the internal combustion engine 101 is in a stopped state, the inside thereof and the inside of the portion communicating with the internal combustion engine 101 are maintained at atmospheric pressure. Therefore, the negative pressure adjusting unit 105 and the space region Kb inside the casing 86 communicating with the negative pressure adjusting unit 105 are also set to atmospheric pressure. Further, the other space region Kf defined by the pressure receiving plate 84 is also at atmospheric pressure, and there is no significant difference between the internal pressures of both space regions Kb and Kf.

  At this time, since the casing 86 is fixed, a pressing pressure (second pressure) by the winding spring 85 is constantly applied to the pressure receiving surface 84a of the pressure receiving plate 84 that contacts the winding spring 85 inside. . Therefore, since the space areas Kb and Kf have the same atmospheric pressure, the pressure receiving surface 84a is pressed to the space area Kf side. Thereby, the connection tool 83 is pushed in the direction shown by the illustrated arrow Dp. By the way, the connection part 8c between the connection tool 83 and the connection tool 82 and the connection part 8a between the connection tool 82 and the connection tool 81 are non-fixed ends, that is, gangs. In addition, the junction part with the non-return valve 7 in the connection tool 81 is also a non-fixed end. On the other hand, the joint portion 8b of the connector 82 to the support member is a fixed end, that is, a static node.

  Therefore, when the connecting tool 83 moves in the direction indicated by the arrow Dp in the drawing, the connecting portion 8c moves in the same direction, and the connecting tool 82 rotates about the joint portion 8b, so that the connecting portion 8a and thus the connecting tool 81 moves. Move downward (in the direction indicated by the arrow Dd in the figure). Accordingly, the check valve 7 joined to the connector 81 is pulled down so as to move away from the oil discharge port 61 in conjunction with the connector 81. With this operation, when the oil discharge port 61 is opened and the oil component L is stored in the oil holding tank 6, the oil component L is sent to the oil recovery system 103 through the oil discharge unit 70.

  On the other hand, when the internal combustion engine 101 is in an operating state, an atmospheric pressure that is significantly smaller than the atmospheric pressure, that is, a negative pressure is generated inside the intake system (negative pressure generating portion) such as an intake manifold. Further, the negative pressure adjusting unit 105 communicating with such a part and the space region Kb in the housing 86 are also set to negative pressure. At this time, the negative pressure values in the negative pressure adjusting unit 105 and the space region Kb are adjusted by the monitor unit 104 so as to be constant and in a desired pressure range according to the operating state or operating conditions of the internal combustion engine 101.

  When the absolute value of the value obtained by multiplying the negative pressure in the space region Kb by the effective area of the pressure receiving surface 84a exceeds the absolute value of the pressing force applied by the winding spring 85 applied to the pressure receiving surface 84a, the pressure receiving plate 84 and the coupler 83 are It moves in the direction indicated by the arrow Dr. When this happens, the connecting portion 8c moves in the same direction, the connecting tool 82 rotates about the joint portion 8b, and the connecting portion 8a and thus the connecting tool 81 moves upward (in the direction indicated by the arrow Du in the drawing). Accordingly, the check valve 7 joined to the connector 81 is driven upward so as to approach the oil discharge port 61 in conjunction with the connector 81. With this operation, the check valve 7 comes into contact with the periphery of the oil discharge port 61 so as to cover it, and the oil discharge port 61 is closed. Therefore, the oil component L separated from the blow-by gas generated by the operation of the internal combustion engine 101 is stored in the oil holding tank 6.

  Therefore, according to the breather device 1, as described above, the check valve 7, the link mechanism 8, and the negative pressure adjusting unit 105 constitute an opening / closing mechanism, whereby the opening / closing operation of the oil discharge port 61 is performed by the internal combustion engine 101. It is forcibly executed according to the state (run / stop). As a result, the check valve 7 can be reliably prevented from sticking in a state of covering the oil discharge port 61 due to an increase in viscosity due to the deterioration of the oil component L or the like. Therefore, since the oil component L can be reliably discharged from the oil holding tank 6, it is possible to prevent the excessive amount of the oil component L from exceeding the permissible value from accumulating therein.

  Therefore, it is possible to sufficiently prevent a large amount of oil L from flowing from the oil holding tank 6 to the intake system 102 and then to the internal combustion engine 101 through the oil separator 2 instantly. As a result, it is possible to prevent performance degradation and damage due to load impact applied to the internal combustion engine 101 and the intake system 102.

  In addition, this invention is not limited to embodiment mentioned above, A various deformation | transformation is possible in the limit which does not deviate from the summary. For example, the monitor unit 104 and the negative pressure adjusting unit 105 are not necessarily required, and the casing 86 may be directly connected to the internal combustion engine 101 or the negative pressure generating unit in the intake system 102. In this case, the range of negative pressure assumed according to the operating conditions of the internal combustion engine 101 and the balance between the effective area of the pressure receiving surface 84a and the pressing force by the winding spring 85 are obtained in advance, and based on the results. The pressing force of the winding spring 85 against the pressure receiving plate 84 and / or the effective area of the pressure receiving plate 84 can be appropriately adjusted. By appropriately changing the effective area of the pressure receiving plate 84, the drag force against the pressing force of the winding spring 85, that is, the tensile force acting on the entire pressure receiving plate 84 can be easily adjusted even if the negative pressure value is the same.

  Further, a negative pressure other than the internal combustion engine 101 or the intake system 102, for example, a negative pressure forcibly generated by a decompression pump or the like may be used. From the viewpoint of further simplifying the configuration of the vehicle or the like, the internal combustion engine 101 It is desirable to use the negative pressure of the intake system 102. Furthermore, oil separators other than the cyclone separator may be used. Furthermore, a plurality of oil separators 2 may be provided. Furthermore, the shape of the oil holding tank 6 is not limited. For example, the lower part may have an inverted conical shape, the oil discharge port 61 may be provided at the lower end thereof, and the check valve 7 and the oil discharge part 70 may be connected thereto. .

  The breather device according to the present invention can reliably prevent sticking of the valve body that opens and closes the discharge port provided in the oil holding portion where the oil component separated and removed from the blow-by gas is temporarily stored. It can be reliably discharged from the holding part. Therefore, it is possible to prevent an excessive amount of oil from accumulating in the oil holding portion. In addition, it is possible to reliably prevent the oil component from flowing into the internal combustion engine at once, and to eliminate the risk of damage to the internal combustion engine and its surrounding parts. The present invention can be widely used for an internal combustion engine that is designed and for which further reliability and safety are sought, and equipment, motives, equipment, and the like equipped with such an internal combustion engine.

It is a figure which shows the structure and principal part cross section of suitable one Embodiment of the breather apparatus by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Breather apparatus, 2 ... Oil separator, 2a ... Oil introduction port, 3 ... Gas supply pipe, 3a ... Gas introduction port, 4 ... Gas discharge pipe, 4a ... Lower end, 6 ... Oil holding tank (oil holding part), 7 ... Check valve (valve element), 8 ... Link mechanism, 8b ... Joint part, 8a, 8c ... Connection part, 9a ... Through hole, 9, P1, P2, P3, P5 ... Pipe, 61 ... Oil discharge port (exhaust) Outlet), 70 ... oil discharge part, 81, 82, 83 ... connector, 84 ... pressure receiving plate, 84a ... pressure receiving surface (surface), 85 ... coil spring (elastic body), 86 ... housing, 90 ... support member, DESCRIPTION OF SYMBOLS 101 ... Internal combustion engine, 102 ... Intake system, 103 ... Oil recovery system, 104 ... Monitor part, 105 ... Negative pressure adjustment part, 211 ... Trunk part, 212 ... Reverse cone part, 213 ... Oil discharge pipe, Kb, Kf ... Space Area, L ... oil content.

Claims (4)

A gas-liquid separation unit that is connected to the internal combustion engine, is supplied with blow-by gas containing oil and gas, and performs gas-liquid separation of the blow-by gas;
An oil holding portion connected to the gas-liquid separation portion, storing an oil component separated from the blow-by gas, and provided with an outlet for the oil;
An opening / closing mechanism having a valve body and a drive unit that is connected to the valve body and drives the valve body to open and close the discharge port according to the state of the internal combustion engine;
A breather device. The opening / closing mechanism closes the discharge port when the internal combustion engine is operated, and opens the discharge port when the internal combustion engine is stopped.
The breather device according to claim 1. The opening / closing mechanism is applied with a first force that moves the valve body so that the discharge port is closed or a second force that moves the valve body so that the discharge port is opened. Having a surface formed so as to interlock with the valve body,
The breather apparatus according to claim 1 or 2. The opening / closing mechanism applies the first force to the surface when the internal combustion engine is operating, and applies the second force to the surface when the internal combustion engine is stopped. Is,
The breather device according to claim 3.

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