WO2020052657A1

WO2020052657A1 - Filter-type engine oil-gas separation device

Info

Publication number: WO2020052657A1
Application number: PCT/CN2019/105737
Authority: WO
Inventors: 覃星念; 朱雄; 赵宁宁; 韦福观; 叶双超; 余晓强
Original assignee: 广西玉柴机器股份有限公司
Priority date: 2018-09-14
Filing date: 2019-09-12
Publication date: 2020-03-19
Also published as: CN109209559A

Abstract

A filter-type engine oil-gas separation device comprises a pre-separation device (200) disposed in a cylinder head cover (100). The pre-separation device (200) is provided with a gas inlet hole (212) and a gas discharge hole (213). The cylinder head cover (100) and the pre-separation device (200) are combined to form an oil-gas channel. The pre-separation device (200) comprises: a filter plate (202) arranged on a base plate (201), and a rough separation device and a fine separation device parallel to each other and arranged on the base plate (201), wherein the fine separation device is located behind the rough separation device, and the gas discharge hole (213) is disposed behind the fine separation device. The filter-type engine oil-gas separation device performs secondary acceleration on an oil-gas mixture, such that a large oil drop and a small oil drop are respectively separated and flow out of oil return cavities (208, 210), thereby improving separation efficiency. During absorption of small oil drops, the impact force of the secondary acceleration prevents a filter element (206) from being clogged with residue, thereby eliminating the need to replace the filter element (206) regularly, and solving the issue of regular replacement and maintenance.

Description

Filter type engine oil-gas separation device

Technical field

The invention belongs to the technical field of oil-gas separation, and particularly relates to a filter-type engine oil-gas separation device.

Background technique

The high-temperature gas generated by the engine during operation can penetrate into the crankcase through the gap between the piston group and the cylinder, causing gas leakage. The components of blow-by gas are unburned fuel gas, water vapor, and exhaust gas. Water vapour condenses and dilutes the oil in the engine oil, reducing the performance of the engine oil; sulfur dioxide in the exhaust gas encounters air oxidation to generate sulfuric acid, which accelerates the oxidative deterioration of the engine oil, which will cause corrosion and accelerated wear of engine parts; blow-by gas will also cause the crankcase to Excessive pressure will damage the seal of the crankcase, causing oil leakage and loss; accelerating the aging of the oil and reducing reliability. Therefore, a crankcase ventilation system is required to control blow-by gas. When the blow-by gas flows through the crankcase ventilation system, it will carry a large amount of oil and gas, causing oil loss and worsening emissions. Therefore, oil and gas must be separated to reduce oil loss. By integrating the oil and gas separator in the cylinder head cover to separate the oil and gas exhausted by the engine, the traditional cylinder head cover can only perform a single separation, and the effect is not as expected.

For example, the Chinese utility model patent “A cylinder head cover” with the publication number of CN205559013U includes a cylinder head cover body, and an oil and gas pre-separation chamber is formed inside the cylinder head cover body. The oil and gas pre-separation chamber is provided with a pre-separation air inlet. And a pre-separation gas outlet, in the oil-gas pre-separation chamber from the pre-separation air inlet to the pre-separation gas outlet, a plurality of lateral partitions arranged in a vertical direction and a labyrinth space in a horizontal direction are sequentially arranged. A plurality of vertical partitions, a horizontal partition and a vertical partition form a labyrinth-type oil and gas passage that communicates with the pre-separated air inlet and the pre-separated air outlet, and an oil-gas separator is integrated on the outer side wall of the cylinder head cover. From the above, it can be found that the core of the pre-separation of oil and gas in the cylinder head cover in the prior art lies in the labyrinth-like oil and gas passage formed between the horizontal partition and the vertical partition, but its single-layer structure has poor oil and gas separation capabilities and cannot separate fine oil. drop.

For example, the Chinese invention patent application with publication number CN108049937A, "Built-in oil and gas separation system in cylinder head cover", includes a built-in oil and gas separator, including: a cover body, a labyrinth cavity and a bottom cover provided on one side of the cover body, the labyrinth One end of the cavity is provided with an air outlet pipe extending to the outside of the cover, and a ventilator socket is opened at the top; the labyrinth cavity is provided with a coarse filter plate, a circuitous rectification structure, a fine filter plate and a partition plate. From the above, it can be found that, in the prior art, the oil and gas pre-separation device of the cylinder head cover is provided with a coarse filter orifice plate and a circuitous rectification structure, which can be used for oil and gas separation, but the large oil droplets (oil droplets with a diameter greater than 10um) are Oil droplets (referring to the diameter of oil droplets of 2 to 10um) are easy to mix, and do not have the effect of oil droplet adsorption and diversion, which will cause the diameter of the oil droplets entering the fine filter orifice plate to remain large. For the treatment of small oil droplets (referring to oil droplets) (Diameter of 0.1 to 2um) has a very large impact; the circuitous rectification structure disclosed in the prior art cannot solve the problem of secondary fragmentation (collision splash) of oil droplets generated by high-speed collisions of oil and gas mixtures, and the oil droplets flow through the collision circuitous After the rectifying structure cannot be recovered by adsorption, it will still follow the flow of the oil and gas mixture to the outlet, resulting in low separation efficiency.

Summary of the Invention

The purpose of the present invention is to overcome the shortcomings of the prior art described above, and provide a new separator gas-driven engine oil-gas separation device that can not only classify ultra-large oil droplets, large oil droplets, and small oil droplets, but also has high separation efficiency, It can solve the problems of oil droplet adsorption and recovery and collision and splashing, and it does not require regular maintenance and replacement of the filter element, which can meet the requirements of the National VI engine.

The object of the present invention is achieved by the following technical solutions:

The invention provides a filter-type engine oil-gas separation device, comprising: a pre-separation device provided in a cylinder head cover, the pre-separation device is provided with an air inlet hole for receiving an oil-gas mixture in a crankcase and a device for separating After exhaust gas is exhausted, the cylinder head cover and a pre-separation device are combined to form an oil and gas channel. The pre-separation device includes a filter plate arranged on the bottom plate, and the air inlet hole is arranged on the filter plate. The oil and gas mixture in the crankcase flows from the air inlet on the filter plate. Due to the effect of the filter plate, when the oil and gas mixture enters, some large oil droplets will collide with the filter plate and flow back; A coarse separation device composed of a filter plate, a first filter baffle, a first oil return cavity on the bottom plate, and a first oil return pipe below the coarse separation device, the coarse separation device is located behind the filter screen plate and is used for conducting oil and gas mixtures. Accelerating collision to further separate large oil droplets; a fine separation device consisting of a second filter plate, a filter element and a second filter baffle, a second oil return chamber on the bottom plate, and a second oil return pipe below, arranged in parallel on the bottom plate,所述细 The fine The crude off means located behind the separating apparatus, fuel-air mixture for again further separated oil droplet collision acceleration, the exhaust hole is provided at the rear of the fine separation device, the exhaust hole for discharging gas after separation.

The first filter plate in the coarse separation device is provided with coarse filter holes for accelerating the oil-gas mixture. In one embodiment, a filter rib is provided on the first filter baffle for guiding oil droplets to the first oil return cavity. In another embodiment, a useful filter baffle is provided on the first filter baffle. Needle-shaped protrusions for increasing the contact area of oil-gas collision, the needle-like protrusions can effectively prevent secondary breakage of oil droplets due to high-speed collision, and improve the efficiency of oil-gas separation. The first oil return chamber is disposed below the first filter baffle. The first filter baffle is a non-closed opening structure for the flow of the oil and gas mixture. The first oil return pipe is provided in the first oil return chamber. bottom.

In one embodiment, a second filter plate, a filter element and a second filter baffle in the fine separation device are closely arranged on the bottom plate; A secondary acceleration fine filter hole, the second filter baffle is provided with two filter ribs for collisionally separating small oil droplets and guiding the small oil droplets to a second oil return cavity, and the second oil return cavity is provided Behind the second filter baffle, the second filter baffle is a non-closed opening structure, and the second oil return pipe is disposed at the bottom of the second oil return cavity.

In one embodiment, the first oil return pipe and the second oil return pipe are further provided with an umbrella-shaped oil return valve that prevents exhaust gas from recoiling into the pre-separation device, which can effectively prevent the gas oil pre-separation efficiency from being affected by the exhaust gas recoil.

In one embodiment, the material of the filter element is any one of non-woven fabric, felt, glass fiber, and synthetic fiber.

In an embodiment, the distance between the first filter plate and the first filter baffle is 2 to 5 mm, and the diameter of the coarse filter hole can be set to 3 to 6 mm according to the amount of air intake of the air inlet. The number of coarse filter holes is set to 10 to 45, so that the flow rate through the first filter plate is controlled at 5 to 8 m / s, and the oil and gas mixture flowing through the first filter plate is in contact with the first filter baffle within this flow rate range. The effect of separating large oil droplets is good.

In one embodiment, according to the amount of air intake of the air inlet hole, the pore diameter of the fine filter hole can be set to 2 to 3 mm, and the number of the fine filter holes is set to 8 to 54 to pass through the second filter. The flow rate of the orifice plate is controlled at 15-30 m / s, and the oil and gas mixture flowing through the second filter orifice plate has a good effect of separating small oil droplets by colliding with the second filter baffle within this flow rate range.

Compared with the prior art, the advantages of the present invention are:

The filter-type engine oil and gas separation device can block the inhalation of some large oil droplets during the intake phase, and can also accelerate the oil and gas mixture twice to separate the large oil droplets and small oil droplets and flow out through the oil return cavity. The separation efficiency High; in the adsorption of small oil droplets, the filter element will not be blocked by residue due to the impact of the secondary acceleration, so there is no need to replace the filter element regularly, which can solve the problem of periodic replacement and maintenance. In addition, the filter-type engine oil-gas separation device can also According to the size of the air intake, the specifications of the coarse filter holes and the fine filter holes (including the pore size and the number of filter holes) are preset to ensure the flow rate after the primary acceleration and the secondary acceleration, and improve the efficiency of separating and separating oil droplets.

BRIEF DESCRIPTION OF THE DRAWINGS

The following further describes the embodiments of the present invention with reference to the drawings, in which:

1 is a schematic diagram of an internal structure of a cylinder head cover according to an embodiment of the present invention;

2 is a three-dimensional structure diagram of a pre-separation device according to an embodiment of the present invention;

3 is a schematic plan view of a pre-separation device according to an embodiment of the present invention;

4 is a schematic structural diagram of a filter screen according to an embodiment of the present invention;

5 is a three-dimensional structure diagram of a first filter plate and a first filter baffle according to an embodiment of the present invention;

6 is a schematic diagram of a three-dimensional structure of a first filter baffle provided with needle-shaped protrusions according to an embodiment of the present invention;

FIG. 7 is a schematic three-dimensional structure diagram of a second filter plate, a filter element, and a second filter baffle according to an embodiment of the present invention.

In the figure, 100 is the cylinder head cover, 200 is the pre-separation device, 201 is the bottom plate, 202 is the screen plate, 203 is the first filter plate, 204 is the first filter baffle, 205 is the second filter plate, and 206 Is the filter element, 207 is the second filter baffle, 208 is the first oil return chamber, 209 is the first oil return pipe, 210 is the second oil return chamber, 211 is the second oil return pipe, 212 is the air inlet hole, and 213 is exhaust Holes, 215 are coarse filter holes, 216 is a filter bar, 217 is a fine filter hole, 218 is a two filter bar, and 220 is a needle-shaped protrusion.

detailed description

In order to make the objectives, technical solutions, and advantages of the present invention clearer, the following further describes the present invention in detail through specific embodiments with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

In the embodiment of the present invention, a filter-type engine oil-gas separation device is provided. A pre-separation device provided in a cylinder head cover, the pre-separation device is provided with an air inlet hole and an exhaust hole. The pre-separation device can Part of the oil droplets are separated during the intake phase of the oil and gas mixture, and then two accelerated collision separations are performed in the pre-separation device, and the oil droplets are discharged through the oil return pipe. FIG. 1 is a cylinder head cover according to an embodiment of the present invention for providing a fixed installation position of the pre-separation device. As shown in FIG. 1, FIG. 2 and FIG. 3, the cylinder head cover 100 is provided with a pre-separation device 200. The pre-separation device 200 includes:

A filter plate 202 arranged on the bottom plate 201, and the air inlet hole 212 is provided on the filter plate 202 (as shown in Figs. 3 and 4) for sucking the oil and gas mixture in the crankcase of the engine, and the oil and gas mixture enters the pre-separation When the device 200 is installed, due to the function of the filter plate 202, some large oil droplets (oil droplets larger than 10um in diameter) will collide with the filter plate 202 and return, and the remaining oil and gas mixture will enter the pre-separation device 200 through the air inlet hole 212;

A coarse separation device consisting of a first filter plate 203 and a first filter baffle 204 arranged in parallel on the bottom plate 201, a first oil return chamber 208 on the bottom plate 201, and a first oil return pipe 209 thereunder, said rough separation The device is located behind the filter plate 202 and is used to process large oil droplets (referring to the diameter of the oil droplets of 2 to 10um) in the oil and gas mixture; the second filter plate 205, the filter element 206 and the second filter block arranged in parallel on the base plate 201 A fine separation device consisting of a second oil return chamber 210 on the plate 207, a second oil return chamber 210 on the bottom plate 201, and a second oil return pipe 211 therebelow. The fine separation device is located behind the coarse separation device and is used to process small oil droplets in the oil-gas mixture ( (Refers to the diameter of the oil droplets 0.1 to 2um); the exhaust hole 213 is provided behind the fine separation device for exhausting the exhaust gas after separating the oil droplets, the air inlet hole 212, the fine separation device, the coarse separation device and the exhaust hole 213 forms an oil and gas channel.

As shown in FIG. 5, the first filter plate 203 and the first filter baffle 204 in the coarse separation device are arranged in parallel on the bottom plate 201 (refer to FIG. 3); The coarse filter 215 is accelerated once for the oil and gas mixture. In one embodiment, a filter rib is provided on the first filter baffle 204 for colliding and separating large oil droplets (referring to the diameter of the oil droplets of 2 to 10um) and guiding the large oil droplets to the first oil return cavity 208. Strip 216, the first oil return cavity 208 is disposed below the first filter baffle 204, and the first filter baffle 204 is a non-closed opening structure (easy to form an oil and gas channel), and the first oil return pipe 209 It is set at the bottom of the first oil return chamber 208; after the oil and gas mixture flows through the first filter plate 203 and accelerates, it collides with the first filter baffle 204, and large oil droplets will flow into the first oil return chamber through a filter rib 216 208, the remaining oil and gas mixture flows out through the opening portion (oil and gas channel) of the first filter baffle 204; in another embodiment, as shown in FIG. 6, the first filter baffle 204 is provided for increasing oil and gas Collision of the needle-shaped protrusions 220 on the contact area, the needle-shaped protrusions 220 can effectively absorb large oil droplets that collide with the first filter baffle 204 at high speed and guide the oil droplets to the first oil return cavity 208 to prevent large Due to the high-speed collision of oil droplets, secondary fragmentation is caused (large oil droplet collisions are prone to splashing), which improves the efficiency of oil and gas separation. Droplets through the needle into the first boss portion 220 back to the oil chamber 208, the remaining hydrocarbon mixture flowing through the first baffle opening portion was filtered (oil passage) 204 outflow.

In one embodiment, if the air intake volume of the air inlet holes 212 is 60 L / min, the diameter of the coarse filter holes 215 is set to 3 mm, the number of the coarse filter holes 215 is set to 27, and the first The distance between the filter plate 203 and the first filter baffle 204 is set to 2 mm, so that the flow velocity through the first filter plate 203 is controlled at about 5 m / s. At this time, the oil and gas mixture flowing through the first filter plate 203 is at the flow rate. The effect of separating large oil droplets with the first filter baffle 204 is good under the setting of the distance and the spacing. In another embodiment, if the air intake volume of the air inlet hole 212 is 100 L / min, the diameter of the coarse filter hole 215 It is set to 6 mm, the number of the coarse filter holes 215 is set to 10, and the distance between the first filter plate 203 and the first filter baffle 204 is set to 3 mm, so that the flow rate through the first filter plate 203 is controlled At about 6m / s, at this time, the oil and gas mixture flowing through the first filter plate 203 hits the first filter baffle 204 to separate large oil droplets under the setting of the flow velocity and spacing. In another embodiment, For example, if the air intake volume of the air inlet hole 212 is 150 L / min, the diameter of the coarse filter hole 215 is set to 5 mm, the number of the coarse filter holes 215 is set to 25, and the first filter The distance between the plate 203 and the first filter baffle 204 is set to 5 mm, so that the flow velocity through the first filter plate 203 is controlled at about 5 m / s. At this time, the oil and gas mixture flowing through the first filter plate 203 is at the flow rate and distance. The effect of separating large oil droplets with the first filter baffle 204 under the setting is good; in another embodiment, if the air intake of the air inlet 212 is 270L / min, the diameter of the coarse filter 215 is set to 6 mm, the number of the coarse filter holes 215 is set to 20, and the distance between the first filter plate 203 and the first filter baffle 204 is set to 4 mm, so that the flow velocity through the first filter plate 203 is controlled to about 8m / s, at this time, the oil and gas mixture flowing through the first filter plate 203 collides with the first filter baffle 204 under the setting of the flow velocity and spacing to separate large oil droplets. In another embodiment, such as The air intake of the air holes 212 is 270 L / min, the diameter of the coarse filter holes 215 is set to 3 mm, the number of the coarse filter holes 215 is set to 45, the first filter plate 203 and the first filter The distance between the baffles 204 is set to 4 mm, so that the flow velocity through the first filter plate 203 is controlled at about 8 m / s. At this time, the oil and gas mixture flowing through the first filter plate 203 is at this flow rate. A first flap 204 strikes the filter effect good separation of large droplets of the pitch setting.

In one embodiment, as shown in FIGS. 3 and 7, the second filter plate 205, the filter element 206, and the second filter baffle 207 in the fine separation device are closely arranged on the bottom plate 201; The second filter plate 205 is provided with a fine filter hole 217 for secondary acceleration of the oil and gas mixture. When the oil and gas mixture flows through the second filter plate 205, the oil and gas mixture is accelerated twice under the action of the fine filter hole 217 The oil and gas mixture will impact the filter element 206 at a high speed. The lower portion of the filter element 206 is an open structure to facilitate the formation of oil and gas channels. The filter element 206 is used to adsorb small oil droplets after the oil and gas mixture is accelerated twice (referring to the diameter of the oil droplets of 0.1). ~ 2um), where the material of the filter element 206 can be non-woven fabric, felt, glass fiber or synthetic fiber. The filter element 206 uses these materials to absorb oil droplets effectively, and the surface of the filter element 206 is not affected by the high-speed impact of secondary acceleration. Residues can be accumulated, so regular replacement maintenance can be avoided (the filter is directly used in the prior art for oil and gas separation, although its efficiency is high, but it needs to be replaced and maintained regularly, and its maintenance cost is high); said second The filter baffle 207 is provided with two filter ribs 218 for colliding and separating small oil droplets and guiding the small oil droplets to the second oil return cavity 212. The lower part of the second filter baffle 207 is a non-closed opening structure ( Forming an oil and gas channel) to facilitate the flow of the oil and gas mixture. After the oil and gas mixture flows through the filter element 206, under the impact of the second filter baffle 207, small oil droplets flow into the second oil return chamber through the two filter ribs 218, and the remaining oil and gas mixture passes through The opening structure (oil and gas passage) of the second filter baffle 207 enters the next-stage separation device. In one embodiment, if the air intake of the air inlet 212 is 60 L / min, the diameter of the fine filter 217 is set to 2mm, the number of the fine filter holes 217 is set to 18, so that the flow velocity through the second filter plate 205 is controlled at about 18m / s, at this time, the oil and gas mixture flowing through the second filter plate 205 is at this flow rate Shock the filter element 206. After the filter element 206 absorbs small oil droplets, the oil and gas mixture continues to hit the second filter baffle 207 at this flow rate, and a better small oil droplet separation effect can be obtained. In another embodiment, such as the air inlet 212 The air intake is 60 L / min, and the diameter of the fine filter 217 is set to 3 mm. The number of filter holes 217 is set to eight so that the flow velocity through the second filter plate 205 is controlled at about 18 m / s. At this time, the air-fuel mixture flowing through the second filter plate 205 impacts the filter element 206 at this flow rate. After the small oil droplets are adsorbed by 206, the oil-gas mixture continues to hit the second filter baffle 207 at this flow rate, and a better small oil droplet separation effect can be obtained; in another embodiment, the intake air volume of the air intake hole 212 is 120L / min, the pore diameter of the fine filter holes 217 is set to 2.5 mm, and the number of the fine filter holes 217 is set to 20 so that the flow velocity through the second filter plate 205 is controlled to about 20 m / s. At this time, The oil and gas mixture flowing through the second filter plate 205 impacts the filter element 206 at this flow rate. After the filter element 206 absorbs small oil droplets, the oil and gas mixture continues to hit the second filter baffle 207 at this flow rate, and a better small oil droplet separation effect can be obtained. In another embodiment, if the air intake volume of the air inlet holes 212 is 180 L / min, the diameter of the fine filter holes 217 is set to 2.5 mm, and the number of the fine filter holes 217 is set to 23, so that The flow velocity through the second filter plate 205 is controlled at about 27 m / s. At this time, the oil and gas mixture flowing through the second filter plate 205 is at The filter element 206 is impacted at a flow rate. After the filter element 206 absorbs small oil droplets, the oil and gas mixture continues to hit the second filter baffle 207 at the flow rate, and a better small oil droplet separation effect can be obtained. In another embodiment, such as an air intake hole The air intake of 212 is 260 L / min, the diameter of the fine filter holes 217 is set to 3 mm, and the number of the fine filter holes 217 is set to 24, so that the flow velocity through the second filter plate 205 is controlled to about 27 m. / s, at this time, the oil and gas mixture flowing through the second filter plate 205 impinges on the filter element 206 at this flow rate. After the filter element 206 absorbs small oil droplets, the oil and gas mixture continues to hit the second filter baffle 207 at this flow rate. Separation effect of small oil droplets; in another embodiment, for example, if the air intake volume of the air inlet 212 is 270L / min, the diameter of the fine filter holes 217 is set to 2mm, and the number of the fine filter holes 217 is set It is 54 so that the flow velocity through the second filter plate 205 is controlled at about 30 m / s. At this time, the oil and gas mixture flowing through the second filter plate 205 impacts the filter element 206 at this flow rate, and the filter element 206 absorbs small oil droplets after the oil and gas The mixture continues to hit the second filter baffle 207 at this flow rate to obtain better small oil droplets. seperate effect.

In one embodiment, referring to FIG. 2, the first oil return pipe 209 and the second oil return pipe 211 are further provided with an umbrella-shaped oil return valve (not shown in the figure) to prevent exhaust gas from recoiling into the pre-separation device 200. It can effectively prevent the pre-separation efficiency of oil and gas due to exhaust gas recoil.

As can be seen from the above embodiments, compared with the prior art, the filter-type engine oil-gas separation device according to the embodiment of the present invention can separate part of the oil droplets during the intake phase of the oil-gas mixture, and then accelerate the oil-gas mixture twice, respectively Separate large oil droplets and small oil droplets and flow out through the oil return chamber, the separation efficiency is high; the specifications of the coarse filter holes and the fine filter holes (including the pore size and the number of filter holes) can be preset according to the amount of air intake. This guarantees the flow rate after the primary acceleration and secondary acceleration, improves the efficiency of impacting and separating oil droplets, and can finally meet the national VI emission standards.

References to "some embodiments", "one embodiment", or "an embodiment" in this specification refer to a particular feature, structure, or property described in connection with the embodiment being included in at least one embodiment . Thus, the appearances of the phrases "in various embodiments", "in some embodiments", "in one embodiment", or "in embodiments" and the like in various places throughout the specification do not necessarily refer to the same implementation example. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. Thus, a particular feature, structure, or property shown or described in connection with one embodiment can be combined, in whole or in part, with a feature, structure, or property of one or more other embodiments without limitation, as long as the combination is not a non- Logical or not working. In addition, each element in the drawings of the present application is for illustrative purposes only, and is not drawn to scale.

Several aspects of at least one embodiment of the present invention are thus described, and it will be understood that various changes, modifications, and improvements can be easily made by those skilled in the art. Such changes, modifications, and improvements are intended to be within the spirit and scope of the invention.

Claims

A filter-type engine oil-gas separation device includes a pre-separation device provided in a cylinder head cover, the pre-separation device is provided with an air inlet hole and an exhaust hole, and the cylinder head cover and the pre-separation device are combined to form oil and gas. A channel, wherein the pre-separation device includes:

A filter plate arranged on the bottom plate, and the air inlet holes are arranged on the filter plate;

A coarse separation device consisting of a first filter plate and a first filter baffle arranged in parallel on the bottom plate, a first oil return cavity on the bottom plate, and a first oil return pipe below, the coarse separation device is located behind the screen plate ;

A fine separation device consisting of a second filter plate, a filter element and a second filter baffle arranged in parallel on the bottom plate, a second oil return cavity on the bottom plate, and a second oil return pipe below, the fine separation device is located in the coarse separation Behind the device, the exhaust hole is provided behind the fine separation device.
The filter-type engine oil-gas separation device according to claim 1, wherein a coarse filter hole is provided on a first filter plate in the coarse separation device, and a filter rib is provided on the first filter baffle plate. Strip or needle-like protrusion, the first oil return cavity is disposed below the first filter baffle, the first filter baffle is a non-closed opening structure, and the first oil return pipe is disposed on the first The bottom of the oil cavity.
The filter-type engine oil-gas separation device according to claim 1, characterized in that: the second filter orifice plate, the filter element and the second filter baffle in the fine separation device are closely arranged on the bottom plate; The second filter plate is provided with fine filter holes, the second filter baffle is provided with two filter ribs, the second oil return cavity is disposed behind the second filter baffle, and the second filter baffle is provided. It is a non-closed open structure, and the second oil return pipe is disposed at the bottom of the second oil return cavity.
The filter-type engine oil-gas separation device according to claim 1, wherein the material of the filter element is any one of non-woven fabric, felt, glass fiber, or synthetic fiber.
The filter-type engine oil-gas separation device according to claim 1, wherein an umbrella-shaped oil return valve is provided on the first oil return pipe and the second oil return pipe to prevent exhaust gas from recoiling into the pre-separation device.
The filter-type engine oil-gas separation device according to claim 2, wherein the distance between the first filter plate and the first filter baffle is 2 to 5 mm, and the diameter of the coarse filter hole is 3 to 6 mm. The number of the coarse filtering holes is 10 to 45.
The filter-type engine oil-gas separation device according to claim 3, wherein the diameter of the fine filter holes is 2 to 3 mm, and the number of the fine filter holes is 8 to 54.