JP2011252462A - Oil mist separator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oil mist separator capable of preventing re-scattering of oil trapped by a filter to improve efficiency of oil mist trap.SOLUTION: An oil mist separation chamber 16 partitioned by a baffle plate 12 is formed in a cylinder head cover 11. In the oil mist separation chamber 16, a filter 17 is supported, oil mist in blowby gas is trapped by the filter 17, and the trapped oil is returned from a recovery hole 24 of the baffle plate 12 to a crank case. The blowby gas from which the oil mist is removed is supplied from a supply hole 26 of the cylinder head cover 11 to an intake system of an engine. A guide member 28 collecting the oil oozing from the filter 17 and guiding it to the recovery hole 24 of the baffle plate 12 is provided downstream of the filter 17.

Description

  The present invention relates to an oil mist separator for efficiently separating oil mist from blow-by gas generated in an engine combustion chamber.

  When fuel burns in the combustion chamber of an automobile engine, unburned gas (blow-by gas) leaks into the crankcase from the gap between the cylinder block and the piston or piston ring. If this blow-by gas is discharged as it is, the load on the environment is large, and therefore a system has been implemented in which the blow-by gas is returned to the intake manifold for combustion. In this case, since oil mist is contained in the blow-by gas, an oil mist separator for separating the oil mist has been conventionally proposed.

  As this type of oil mist separator, for example, one having a structure described in Patent Document 1 is known. That is, the oil mist separation structure includes a filter element for separating oil, and the filter element is configured such that blow-by gas passes from top to bottom. Therefore, the oil in the filter element collected from the blow-by gas falls by its own weight, and the oil can be pushed downward by the flow from the top to the bottom of the blow-by gas.

JP 2006-152890 A

  In the oil mist separation structure described in Patent Document 1, the oil in the filter element (filter) collected from blow-by gas falls on the baffle plate provided between the lower end portion and the crankcase. Then, it is returned to the crankcase from a hole provided in the baffle plate. However, since the oil falls from the entire lower surface of the filter element and the particle diameter of the oil is small, there is a possibility that when the oil falls from the filter element, it is scattered again by the flow of blow-by gas. For this reason, the recovery rate is deteriorated by the amount of oil once trapped by the filter element, and therefore the oil mist capturing efficiency is low.

  Accordingly, an object of the present invention is to provide an oil mist separator that can suppress re-scattering of oil captured by a filter and improve oil mist capturing efficiency.

  In order to achieve the above object, in the oil mist separator according to the first aspect of the present invention, an oil mist separation chamber is formed in the cylinder head cover of the engine, and a filter is supported in the oil mist separation chamber. The oil mist in the blow-by gas introduced into the separation chamber is captured by the filter, and the captured oil is returned to the cylinder head side, and the blow-by gas from which the oil mist has been removed passes through the supply hole of the cylinder head cover and the intake system of the engine The oil mist separator is configured to be supplied to the bottom of the filter, and is provided with a guide member that collects the oil exuded from the filter and guides it to the cylinder head side at the bottom of the filter. .

An oil mist separator according to a second aspect of the invention is characterized in that, in the invention according to the first aspect, the guide member is integrally formed with a filter.
The oil mist separator according to a third aspect of the invention is characterized in that, in the invention according to the first aspect, the guide member is formed by adhering a hard resin separate from the filter to the filter.

  The oil mist separator according to a fourth aspect of the present invention is the invention according to any one of the first to third aspects, wherein the guide member has a guide groove that becomes lower toward the downstream side of the blow-by gas. To do.

  An oil mist separator according to a fifth aspect of the invention is characterized in that, in the invention according to any one of the first to fourth aspects, the guide member is formed wider toward the downstream side of the blow-by gas. To do.

According to the present invention, the following effects can be exhibited.
In the oil mist separator of the present invention, a guide member is provided at the bottom of the downstream side of the filter to collect oil that oozes from the filter and guides it to the cylinder head side. For this reason, the oil that oozes out from the filter is collected by the guide member and guided to the cylinder head side, and is less susceptible to the influence of blow-by gas.

  Therefore, according to the oil mist separator of the present invention, re-scattering of the oil captured by the filter can be suppressed, and the efficiency of capturing the oil mist can be improved.

The schematic sectional drawing which shows the oil mist separator in embodiment of this invention. (A) is a cross-sectional view showing an oil mist separator, (b) is a cross-sectional view taken along line 2b-2b of (a), and (c) is a cross-sectional view showing a filter and a guide member. Sectional drawing which shows another example of a guide member. Sectional drawing which shows another example of a guide member. Sectional drawing which shows a guide member in case the filter is arrange | positioned in the perpendicular direction.

Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2.
As shown in FIG. 1, a cylinder head cover 11 is attached to a cylinder head of an automobile engine, and a baffle plate 12 is supported inside the cylinder head cover 11. The upstream partition wall 14 and the downstream partition wall 15 that are installed between the top wall 13 of the cylinder head cover 11 and the baffle plate 12 are arranged so as to face each other, and the upstream partition wall 14 and the downstream partition wall thereof are arranged. 15, an oil mist separation chamber 16 is formed. In the oil mist separation chamber 16, the filter 17 is horizontally disposed by being supported by the upstream partition wall 14 and the downstream partition wall 15 at the support portions 18 at both ends thereof. This filter 17 is comprised, for example with the nonwoven fabric etc. which were formed with polyester resins, such as polyethylene terephthalate resin (PET).

  As shown in FIGS. 2A and 2B, the filter 17 includes a pair of filter portions 17a and 17b having a substantially trapezoidal cross section. The filter parts 17a and 17b are adapted to capture oil mist in the blow-by gas.

  As shown in FIG. 1, a space surrounded by the upstream partition wall 14, the cylinder head cover 11 and the baffle plate 12 becomes an upstream space portion 19, and a space surrounded by the downstream partition wall 15, the cylinder head cover 11 and the baffle plate 12. Is the downstream space 20. The baffle plate 12 is provided with a communication hole 21 communicating with the upstream space 19 so that blow-by gas in the crank chamber is guided to the upstream space 19. A blow-by gas inflow hole 22 is opened in the upper part of the upstream partition wall 14, and a blow-by gas outflow hole 23 is opened in the lower part of the downstream partition wall 15. The blow-by gas in the upstream space portion 19 flows into the oil mist separation chamber 16 from the inflow hole 22, and after the oil mist is captured by the filter 17, it flows into the downstream space portion 20 from the outflow hole 23. It has become.

  An oil recovery hole 24 is opened in the baffle plate 12 on the downstream side of the oil mist separation chamber 16. A gas supply pipe 25 communicating with the downstream space 20 is penetrated and supported in the cylinder head cover 11 so that blow-by gas in the downstream space 20 is sent from the supply hole 26 of the gas supply pipe 25 to the intake system of the engine. It has become.

  A guide member 28 that guides the oil 27 that oozes out from the filter 17 to the recovery hole 24 of the baffle plate 12 is integrally formed at the bottom of the filter 17 on the downstream side. The guide member 28 is formed by compressing and solidifying the nonwoven fabric of the filter 17 and is formed in a bowl shape. As shown in FIGS. 2B and 2C, the guide member 28 extends in the left-right direction in FIG. 2C at the center thereof, and has a V-shaped cross section that becomes lower toward the recovery hole 24 side of the baffle plate 12. There is a groove 29, and an opening 30 through which oil 27 falls is formed at the downstream end of the guide groove 29. Therefore, as shown in FIG. 1, the oil 27 oozing out from the filter 17 through the guide groove 29 is guided to the recovery hole 24.

  As shown by the broken line in FIG. 2A, the guide member 28 is disposed in the downstream half of the blow-by gas flow direction of the filter 17, and is formed in a tapered shape that gradually increases in width from the upstream side toward the downstream side. Has been. The oil mist separator 10 includes the cylinder head cover 11, the baffle plate 12, the recovery hole 24, the filter 17, the guide member 28, and the like.

The operation of the oil mist separator 10 configured as described above will be described.
As shown in FIG. 1, when separating the oil mist in the blow-by gas, the blow-by gas in the crank chamber enters the upstream space portion 19 from the communication hole 21, and the oil mist separation chamber from the inflow hole 22 of the upstream partition wall 14. 16 flows in. In the oil mist separation chamber 16, blow-by gas flows through the filter 17 as shown by the arrows in the figure.

  At this time, the oil mist in the blow-by gas is captured in the nonwoven fabric of the filter 17, and a part of the oil mist falls on the baffle plate 12 from the portion of the filter 17 where the guide member 28 is not present, and the rest reaches the guide member 28. In this case, oil mist having a large particle diameter is likely to fall and is captured upstream of the filter 17, and oil mist having a small particle diameter is captured downstream of the filter 17. The oil 27 dropped on the baffle plate 12 flows on the baffle plate 12 and reaches the cylinder head side from the recovery hole 24.

  In the guide member 28, the oil 27 is collected in the guide groove 29 and falls from the opening 30 toward the collection hole 24 of the baffle plate 12. The blow-by gas after the oil mist is separated enters the downstream space portion 20 through the outflow hole 23 of the downstream partition wall 15, is discharged from the supply hole 26 of the gas supply pipe 25, and is sent to the intake system of the engine. .

The effects exhibited by the oil mist separator 10 of the embodiment described in detail above will be collectively described below.
(1) In the oil mist separator 10 of the present embodiment, a guide member 28 is provided on the downstream side of the filter 17 to collect the oil 27 oozing out from the filter 17 and guide it to the recovery hole 24 of the baffle plate 12. At this time, since the blow-by gas does not pass through the guide member 28, the oil 27 oozing out from the filter 17 is less likely to be re-scattered when guided by the guide member 28 and guided to the collection hole 24 of the baffle plate 12. . As a result, the oil 27 falls into the collection hole 24 of the baffle plate 12 and is collected into the crank chamber.

  Therefore, according to the oil mist separator 10 of the present embodiment, the oil 27 captured by the filter 17 can be returned to the crank chamber without being scattered again, and the oil mist capturing efficiency can be remarkably improved.

  (2) The guide member 28 has a guide groove 29 that becomes lower toward the collection hole 24 side of the baffle plate 12. For this reason, the oil 27 that has oozed out of the filter 17 quickly flows to the collection hole 24 side of the baffle plate 12 and can be collected smoothly.

(3) Since the non-woven fabric is compressed and hard, the guide member 28 can mechanically reinforce the filter 17.
(4) Since the guide member 28 is formed in a taper shape that is wider toward the downstream side of the blow-by gas, the oil 27 captured by the filter 17 can be sufficiently collected by the guide member 28 and the capture efficiency is increased. be able to.

It should be noted that the above embodiment can be modified as follows.
As shown in FIG. 3, the upper surface of the guide member 28 is separated from the lower surface of the filter 17, and an inclined surface 31 that becomes lower toward the guide groove 29 side can be provided. In this case, the oil 27 oozing out from the filter 17 can be easily guided from the inclined surface 31 to the guide groove 29.

  As shown in FIG. 4, the guide member 28 can be made of a hard material separate from the filter 17, and the guide member 28 can be bonded to the lower surface of the filter 17. In this case, since the surface of the guide member 28 is smooth, the oil 27 can be guided smoothly.

  As shown in FIG. 5, in the oil mist separator 10 in which the filter 17 is arranged in the vertical direction and blow-by gas flows from right to left in the drawing, the guide member 28 can be arranged obliquely on the downstream side of the filter 17. . In this case, the oil 27 oozing out from the filter 17 flows down along the guide member 28 and can be guided to the recovery hole 24 of the baffle plate 12.

It is also possible to form the lowermost end portion of the guide member 28 so as to extend into the recovery hole 24 of the baffle plate 12.
The guide groove 29 of the guide member 28 may be formed in a smooth curved surface such as an arc shape so that the collection hole 24 side of the baffle plate 12 is lowered.

  DESCRIPTION OF SYMBOLS 10 ... Oil mist separator, 11 ... Cylinder head cover, 16 ... Oil mist separation chamber, 17 ... Filter, 26 ... Supply hole, 27 ... Oil, 28 ... Guide member, 29 ... Guide groove.

Claims (5)

An oil mist separation chamber is formed in the cylinder head cover of the engine, a filter is supported in the oil mist separation chamber, and the oil mist in the blow-by gas introduced into the oil mist separation chamber is captured and captured by the filter. The oil is returned to the cylinder head side, and the blow-by gas from which the oil mist has been removed is an oil mist separator configured to be supplied from the supply hole of the cylinder head cover to the intake system of the engine,
An oil mist separator, characterized in that a guide member is provided at the bottom of the filter on the downstream side to collect oil that oozes from the filter and guide it to the cylinder head side. The oil mist separator according to claim 1, wherein the guide member is integrally formed with the filter. The oil mist separator according to claim 1, wherein the guide member is configured by bonding a hard resin separate from the filter to the filter. The oil mist separator according to any one of claims 1 to 3, wherein the guide member has a guide groove that becomes lower toward a downstream side of the blow-by gas. The oil mist separator according to any one of claims 1 to 4, wherein the guide member is formed wider toward a downstream side of the blow-by gas.

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