JP2021110240A - Industrial engine - Google Patents

Abstract

[Problem] To solve the above-mentioned problems (1) and (2) by devising a structure based on the idea of positively utilizing the heat of the engine, and achieving a clear anti-freezing effect on the blow-by gas path while reducing costs. To provide an industrial engine improved to obtain A valve mechanism (a) arranged below an in-cover gas passage (W), configured to guide blow-by gas from a crankcase through an in-cover gas passage (W) provided inside a head cover (3) and then to an intake passage. , an oil ejection port 26 for scattering engine oil upward is provided, and the engine oil splashed from the oil ejection port 26 comes into contact with the partition member or the bottom wall 17 forming the gas passage W in the cover. Configured industrial engine. [Selection drawing] Fig. 10

Description

The present invention relates to an engine mounted on an agricultural machine or a construction machine, and has a structure in which a blow-by gas passage is provided in a head cover.

The blow-by gas from the crankcase passes through the gas passage in the cover of the head cover, or the gas passage in the cover and the exterior oil separator, and then is taken out of the head cover and returned to the intake passage by a pipe or the like. For example, in the engine disclosed in Patent Document 1, the head cover and the exterior oil separator are connected by using a pair of supply / discharge pipes (14, 15).

In cold regions such as winter and northern countries, the oil separator and its supply / discharge pipe may be cooled and frozen, so measures such as wrapping a heat insulating material around the pipe or installing a heater in place may be taken. many. These measures are devised to prevent problems such as freezing at low temperatures, deterioration of blow-by function due to the freezing, and oil leakage as much as possible.

In recent years, the following problems (1) and (2) and improvements have been raised.
(1) There are measures to prevent the blow-by gas path from getting cold as much as possible by shortening the blow-by gas path and devising the arrangement, but the effect of preventing cold is not good, so it cannot be dealt with at extremely low temperatures.
(2) A means for providing a heat source such as a heater has a problem of increasing the power burden and cost.

JP-A-2018-3629

An object of the present invention is to solve the above-mentioned problems (1) and (2) by devising a structure based on the idea of actively utilizing the heat of the engine, in order to solve the above-mentioned problems (1) and (2). The point is to provide an improved industrial engine so that the antifreeze effect can be obtained.

The present invention relates to an industrial engine.
The blow-by gas from the crankcase is configured to be guided to the intake passage after passing through the gas passage in the cover provided inside the head cover.
The valve operating mechanism arranged below the gas passage in the cover is provided with an oil spout that disperses engine oil upward.
The engine oil scattered from the oil spout is configured to come into contact with the partition member or the bottom wall forming the gas passage in the cover.

Regarding the present invention, refer to claims 2 to 6 for feature configurations and means other than the above-mentioned configurations (means).

According to the present invention, if the engine is running, the oil continues to scatter (spout) upward from the spout of the valve mechanism, so that the spattered oil is scattered on the partition member or the bottom wall. A situation of continuous hits has been brought about. That is, since the heat of the warm (hot) oil can be used to heat the partition member or the bottom wall, that is, the gas passage in the cover, the temperature of the blow-by gas can also be raised.

Therefore, when the blow-by gas passes through the gas passage in the cover, the temperature of the blow-by gas is also raised by the partition plate that is constantly warmed by the ejected oil, and the temperature of the water contained in the gas is maintained at 0 ° C. or higher and frozen. Will be prevented. Since the temperature of the blow-by gas itself is raised, the moisture is not frozen even in the external piping that is exposed to the outside and the junction with the intake passage.

As a result, by devising a structure based on the idea of actively utilizing the heat of the engine, in order to solve the problems related to (1) and (2) mentioned above, the effect of preventing freezing of the blow-by gas route is clear while saving cost. It is possible to provide an improved industrial engine so that

Top view of industrial diesel engine Right side view of the engine of FIG. Top view of head cover Bottom view of the head cover of FIG. Right side view of the head cover of FIG. Cross-sectional view of the ZZ line in the head cover of FIG. The principle structure of the blow-by gas recirculation device at the head cover part is shown, (A) is a schematic diagram of the separator exterior specification, and (B) is a schematic diagram of the separator interior specification. Bottom view of engine head cover with separator interior Left side view of a partial notch showing the internal structure of the engine of FIG. Perspective view of the main part showing the anti-freezing structure inside the head cover

Hereinafter, an embodiment of an industrial engine according to the present invention will be described with reference to the drawings in the case of an in-line multi-cylinder diesel engine having a blow-by gas recirculation device applied to an agricultural tractor or the like. First, an explanation will be given regarding general industrial engines with separator exterior specifications and common head covers, and then a description regarding prevention of freezing of the blow-by path according to the present invention will be given.

1 and 2 show an in-line 4-cylinder industrial diesel engine (hereinafter simply abbreviated as "engine") E with a blow-by gas recirculation device. In this engine E, the cylinder head 2 is assembled on the cylinder block 1, and the head cover (engine head cover) 3 is assembled on the cylinder head 2. The lower part of the cylinder block 1 is the crankcase 1A, and the oil pan 4 is assembled under the crankcase 1A.

A cooling fan 5, an alternator (cell dynamo) 6, a belt transmission mechanism 7, and the like are arranged in the front part of the engine E, and a flywheel housing 8 is provided in the rear part of the engine E. The alternator 6, the intake manifold 30, the oil separator (engine exterior oil separator) 9, and the like are arranged on the right side of the engine E, and the intake manifold (marked omitted) and the supercharger (turbo) are arranged on the left side of the engine E. ) 11, EGR cooler (notation omitted), etc. are arranged.

The engine E has a specification in which an oil separator 9 for removing an oil component in blow-by gas is arranged outside the head cover 3 as a dedicated component (engine exterior oil separator specification, hereinafter referred to as "separator exterior specification"). Although not shown, the basics are the same as this engine E, but the details are different (eg, the displacement is slightly larger or smaller, the output is different, etc.), so the specification is that the oil separator is inside the head cover (head cover interior oil separator). The engine of the specifications, hereinafter referred to as "separator interior specifications") is also set.

[About the head cover 3 with separator exterior specifications]
In the engine E (engine shown in FIGS. 1 and 2) having a separator exterior, it is necessary to provide a blow-by gas outlet (gas intermediate outlet) and an inlet (gas intermediate inlet) for the exterior oil separator 9 on the head cover 3. However, such outlets and inlets are not required for head covers in engines with separator interior specifications. Therefore, since the head cover 3 with the separator exterior specification and the head cover 33 with the separator interior specification (see FIG. 8) are separate parts, it is a conventional technical common sense that a mold for molding is required for each. rice field.

On the other hand, in the present embodiment, it has succeeded in making it possible to mold the head covers 3 and 33 of each specification with one mold mainly by structurally devising the gas intermediate outlet portion and the gas intermediate inlet portion. Next, the head cover with the above-mentioned structural ingenuity will be described with reference to the head cover 3 having a separator exterior specification.

As shown in FIGS. 3 to 6, the head cover 3 used for the engine E having a separator exterior specification is a stage provided with a protruding cover portion 3A having a part of the upper left portion projecting upward and a main cover portion 3B. It is a bottomless box-shaped part with a cover. The protruding cover portion 3A has a cover ceiling wall 3a and a peripheral wall 3s, and the internal space thereof is a gas passage W in the cover for passing blow-by gas. The main cover portion 3B has a cover upper wall 3b, a cover front wall 3f, a cover rear wall 3r, a cover left wall 3c, and a cover right wall 3d, and the internal space thereof is a valve operating mechanism such as a rocker arm (not shown). It is a valve chamber S for arranging.

3 to 6, 12 is an injector hole, 13 is an oil filler port hole, and 14 is a pressure regulating valve 15 (PCV valve or the like, see FIG. 1) formed at the front end of the protruding cover portion 3A. It is a standing wall. A substantially loop-shaped mounting seat 16 that faces downward and is long in the front-rear direction is formed on the inner bottom portion of the protruding cover portion 3A (see FIG. 4). In the actual machine, the partition plate 17 is bolted to the mounting seat 16. Will be done. The partition plate 17 is a bottom plate member that separates the valve chamber S from the valve chamber S in order to separate (isolate) the gas passage W in the cover, which is a passage for blow-by gas.

That is, the gas passage W in the cover in the separator exterior specification is formed in the head cover 3 as an internal space of the box-shaped structure B composed of the protruding cover portion 3A (cover ceiling wall 3a and peripheral wall 3s) and the partition plate 17. .. In the simple-shaped head cover that does not have the protruding cover portion 3A, the box-shaped structure B may be formed so as to protrude downward from the head cover wall such as the cover upper wall 3b [see FIG. 7 (A), of course. , The configuration may have a protruding cover portion 3A.

At a position slightly rearward of the center of the front and rear of the cover ceiling wall 3a of the protruding cover portion 3A, the gas intermediate outlet portion 18 having an outlet-side through hole 18a communicating with the valve chamber S and the gas passage W in the cover communicate with each other. A gas intermediate inlet portion 19 having a through hole 19a on the inlet side is formed. The right vertical seat portion 16a of the portion corresponding to the gas intermediate outlet portion 18 in the mounting seat 16 is formed in a shape that is recessed to the left in a large arc shape, and the left and right width of the gas passage W in the cover of that portion is on the left side. It is compressed to.

Each of the gas intermediate outlet portion 18 and the gas intermediate inlet portion 19, which are inclined structures, have laterally oblique outlet-side and inlet-side through holes 18a and 19a having an inclination connecting the upper right and the lower left, respectively. It is formed by machining, that is, post-processing, after molding the material of. The gas intermediate outlet portion 18 is arranged slightly to the right of the gas intermediate inlet portion 19 on the rear side in order to open the through hole 18a on the outlet side to the valve chamber S.

A tubular supply passage 24 for sending blow-by gas to the oil separator 9 is connected to the gas intermediate outlet portion 18, and a tubular supply passage 24 for sending blow-by gas from the oil separator 9 to the head cover 3 is connected to the gas intermediate inlet portion 19. The discharge passage 25 of the above is connected. The through hole 19a on the inlet side is arranged and formed so as to face the start end portion (rear end portion) of the gas passage W in the cover. That is, the gas intermediate outlet portion 18 is set to face the outside of the box-shaped structure B, and the gas intermediate inlet portion is set to face the inside of the box-shaped structure B.

A gas outlet 20 for sending blow-by gas that has passed through the pressure regulating valve 15 to a supercharger (an example of an intake passage) 11 is formed on the cover ceiling wall 3a on the front side of the upright wall 14. A recirculation duct 23 connected to the compressor side of the turbocharger 11 is communicated with the gas outlet 20 in a posture of facing diagonally forward to the right. The pressure regulating valve 15 and the upright wall 14 are arranged at the end portion (front end portion) of the gas passage W in the cover.

In an engine having a separator exterior specification, as shown in a schematic diagram in FIG. 7A, blow-by gas g coming up from the cylinder head 2 passes through a valve chamber S and passes through a supply passage 24 from a gas intermediate outlet portion 18. It passes through and enters the oil separator 9. The blow-by gas g after the oil component has been removed by the oil separator 9 enters the gas passage W in the cover through the discharge passage 25 and the gas intermediate inlet portion 19, and also undergoes a slight oil removing action when flowing there. After that, the oil is sent to the recirculation duct 23 through the pressure regulating valve 15 and the gas outlet 20.

[About the head cover with separator interior specifications]
As shown in FIGS. 7B and 8, the head cover 33 of the engine (not shown) having a separator interior specification is located upstream of the gas intermediate outlet portion 18 in the cover ceiling wall 3a in the blow-by gas flow direction. A boss portion 21 in which a female screw portion 22 for screwing the gas passage forming member 34 (or 35) in the cover of the closed specification is formed is provided. The boss portion 21 (see FIG. 8) is also provided in the head cover 3 having a separator exterior specification (see FIG. 4).

The through holes 18a and 19a are not post-processed in the gas intermediate outlet portion 18 and the gas intermediate inlet portion 19 and remain as a cast surface, that is, are closed, and the female screw portion 22 is formed in the boss portion 21 by post-processing. Has been done. Three female threaded portions 22 are also provided at appropriate positions on the mounting seat 16 by post-processing. Therefore, using a total of four female threaded portions 22, the bottom plate member 34 for forming the gas passage W in the cover, or a dedicated part, having a gas outlet and a gas inlet facing the inside of the upright wall 14. A small oil separator (or a blow-by gas passage structure with a built-in separator) 35 can be provided inside the head cover 3.

In an engine with a separator interior specification, as shown in a schematic diagram in FIG. 7B, the blow-by gas g from the cylinder head 2 is transmitted from the gas passage W in the cover by the bottom plate member 34 or the gas inlet 36 of the small oil separator 35. After entering and removing the oil component with the oil filter (or oil separator) 37, the blow-by gas g goes out through the pressure regulating valve 15 and the gas outlet 20. Since the gas intermediate outlet portion 18 and the gas intermediate inlet portion 19 are closed, a separate gas inlet 36 is required. The small oil separator 35 has a gas outlet (not shown).

As described above, the head covers 3 and 33 are integrally formed with a gas intermediate outlet portion 18 having no through holes 18a and 19a, a gas intermediate inlet portion 19, and a boss portion 21 having no female screw portion 22 at the time of mold molding. In this state, the head cover 3 with the separator exterior specification and the head cover 33 with the separator interior specification are exactly the same parts, and therefore only one type of molding die (mold) is required. If the through hole 18a of the gas intermediate outlet portion 18 and the through hole 19a of the gas intermediate inlet portion 19 are made by post-processing on the unprocessed (non-machined state) head cover in the mold molding state to make the opening specification, the separator is used. It can be an exterior specification head cover 3. Then, if the female screw portion 22 is formed in the boss portion 21 by post-processing to have a closing specification that does not form through holes 18a and 19a, the head cover 33 having a separator interior specification can be obtained.

That is, when viewed as a separator exterior specification, the head cover 3 includes a gas passage W in the cover for guiding blow-by gas from the crank case 1A to the intake passage 11, and a cover ceiling wall (head cover wall) at the end of the gas passage W in the cover. ) The gas outlet 20 formed in 3a and the gas intermediate outlet 18 formed in the cover ceiling wall (head cover wall) 3a while facing the valve chamber (the space inside the cover other than the gas passage W in the cover) S. The cover has an intermediate inlet portion 19 formed on the cover ceiling wall (head cover wall) 3a so as to face the gas passage W in the cover.

Then, the gas intermediate outlet portion 18 and / or the gas intermediate inlet portion 19 penetrates the cover ceiling wall (head cover wall) 3a so as to enable the communication connection of the blow-by gas supply / discharge passages 24 and 25 to the engine exterior oil separator 9. There is a choice between an opening specification in which the through holes 18a and 19a are formed, and a closing specification in which the through holes 18a and 19a are not formed so that the oil separator can be arranged on the inner side of the cover ceiling wall (head cover wall) 3a. It is possible.

Therefore, the two types of head covers 3 and 33, which are engines in which the separator exterior specifications and the separator interior specifications are set according to the conditions such as the engine displacement and the usage conditions of the exporting country, and the finishing configurations are different from each other, are the same. Only one type of mold is required, which has the advantage of being able to reduce production costs, parts costs, and parts management costs.

As shown in FIGS. 9 and 10, a valve operating mechanism a provided on the cylinder head 2 is configured inside the head cover 3. The valve operating mechanism a is composed of a push rod (not shown), a rocker arm 27, an intake / exhaust valve (not shown), a rocker arm shaft 28 that pivotally supports the rocker arm 27 so as to swing the balance, and the like. A plurality of bracket portions 29 for axially supporting the rocker arm shaft 28 are projected from the cylinder head 2.

The valve operating mechanism a arranged below the gas passage W in the cover is provided with an oil spout 26 for scattering engine oil upward, and the engine oil scattered from the oil spout 26 is discharged from the gas passage in the cover. It is configured to be in contact with a partition plate (an example of a partition member) 17 forming W.

The oil outlet 26 is provided as a vertical hole that opens in the upper surface 27a of the rocker arm 27, and its position in the left-right direction is located above the rocker arm shaft 28 in the rocker arm 27. The oil (engine oil) discharged from the oil pump (not shown) is supplied to the rocker arm 27 via the bracket portion 29 and the rocker arm shaft 28 and exits from the oil outlet 26, but this structure itself is a public land. Therefore, further explanation is omitted.

By the way, as shown in FIG. 10, when the engine E is rotating and starting, the oil is always scattered (spouted) upward from the oil ejection port 26 of the rocker arm 27, so that the partition plate 17 The bottom surface of the rocker is constantly exposed to scattered oil. That is, since the partition plate 17, that is, the gas passage W in the cover can be heated by using the heat of the warm (hot) oil, the temperature of the blow-by gas can also be raised.

When the blow-by gas passes through the gas passage W in the cover, the temperature of the blow-by gas is also raised by the partition plate 17 which is constantly heated by the ejected oil so that the temperature of the water contained in the gas is maintained at 0 ° C. or higher. And freeze is prevented. Since the temperature of the blow-by gas itself is raised, the moisture is not frozen even in the external piping that is exposed to the outside and the junction with the intake passage.

Since the gas passage W in the cover, that is, the partition plate 17 is a long one that is long in the cylinder series direction (front-rear direction), as shown in FIG. 10, a plurality of oil spouts 26, 26 arranged in the front-rear direction are arranged. In addition to being able to receive the oil injection from 26 and 26, there is an advantage that the temperature rise time of the blow-by gas becomes long and the gas temperature can be raised efficiently.

Further, if the partition plate 17 is made of a metal having excellent heat transfer efficiency such as a rolled steel plate, a mechanical structure steel plate, or an aluminum alloy, the blow-by gas temperature raising action by oil ejection using the valve operating mechanism a is more efficient. It will be possible to make good use of it.

[Another Embodiment]
The present invention can also be applied to a structure in which an independent oil separator is installed in the head cover [see FIG. 7 (B)], and the ejected oil is applied to the bottom wall 34 of the oil separator 35 to apply the sprayed oil to the inside of the oil separator 35. It is possible to raise the temperature of the blow-by gas flowing through the gas passage W in the cover.

1A Crankcase 3 Head cover 11 Intake passage 17 Partition member or bottom wall 26 Oil spout 27 Rocker arm 28 Rocker arm shaft W Gas passage in cover a Valve mechanism

Claims (6)

The blow-by gas from the crankcase is configured to be guided to the intake passage after passing through the gas passage in the cover provided inside the head cover.
The valve operating mechanism arranged below the gas passage in the cover is provided with an oil spout that disperses engine oil upward.
An industrial engine configured such that engine oil scattered from the oil spout comes into contact with a partition member or a bottom wall forming the gas passage in the cover. The industrial engine according to claim 1, wherein the partition member or the bottom wall is formed in a long shape long along the cylinder series direction. The industrial engine according to claim 1 or 2, wherein the oil spout is provided so as to open on the upper surface of the rocker arm. The industrial engine according to claim 3, wherein the oil spout is set at a position above the rocker arm shaft in the rocker arm. Any of claims 1 to 4, wherein a partition member for dividing the inside of the head cover into upper and lower parts is provided, a space above the partition member is formed in the gas passage in the cover, and the partition member is made of a plate material. The industrial engine described in paragraph 1. The industrial engine according to claim 5, wherein the material of the partition member made of a plate material is a metal material.

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