JP2017044144A - Engine device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an engine device which can prevent rapid increase of a pressure in a crankcase of the engine device, and can avoid leakage of lubricating oil in the crankcase even when a pipe line of blow-by gas leaked from a combustion chamber is closed even in use at a cold district, especially at a very cold district of -20°C or lower.SOLUTION: An engine device includes pressure adjusting parts (21, 25, and 29) having a blow-by gas passage through which blow-by gas from a combustion chamber flows, a reducing hose (12) connected to the blow-by gas passage, and blow-by gas mixing joints (20, 20A, 20B, and 20C) for introducing the blow-by gas flowing in the reducing hose to an intake pipe. The pressure adjusting part communicates the blow-by gas passage with the outside when the pressure in the blow-by gas passage exceeds a prescribed pressure.SELECTED DRAWING: Figure 3

Description

  The present disclosure relates to an engine device such as a diesel engine mounted as a power source in various power devices such as work vehicles, agricultural machines, generators, and refrigerators, and in particular, a blow-by gas reduction mechanism that reduces blow-by gas to an intake system. It is related with an engine apparatus provided with.

  In recent years, exhaust gas regulations for engine devices that are internal combustion engines have become stricter year by year, and various countermeasures have been proposed for engine devices in order to comply with exhaust gas regulations. As a countermeasure for exhaust gas in conventional diesel engines, etc., an exhaust gas recirculation (EGR) device that reduces a part of the exhaust gas to the intake side is installed to keep the combustion temperature low and in the exhaust gas. Measures have been taken to reduce the amount of NOx (nitrogen oxide). For example, a configuration in which an exhaust gas purification device used in a diesel engine is improved (for example, see Patent Document 1), or a configuration in which the number of parts of the blow-by gas reduction device is reduced and maintenance inspection work is simplified (for example, Patent Document 2). Have been proposed). Further, a technique has been proposed in which lubricating oil is separated from blow-by gas leaking from the combustion chamber, and the blow-by gas from which the lubricating oil has been separated is returned to the intake system and recirculated.

JP2013-13396A JP2013-148010A

  In the configuration in which the blow-by gas in the crankcase leaking from the combustion chamber is returned to the intake system, the blow-by gas contains moisture as well as the oil that is the lubricating oil, so use in cold regions, especially in extremely cold regions of -20 ° C or lower. Had a big problem. In cold regions, particularly in extremely cold regions of −20 ° C. or lower, the blow-by gas is rapidly cooled at the joint portion between the intake air (external air) and the blow-by gas, the moisture contained in the blow-by gas freezes, and the blow-by gas flows. The phenomenon of icing on the pipeline occurs. As a result, the blow-by gas conduit is blocked by ice, the pressure in the crankcase of the engine device increases, and the lubricating oil inside the crankcase leaks. Furthermore, as a result of leakage of the lubricating oil, the lubricating oil is insufficient, and there is a possibility that the equipment (for example, the supercharger) is damaged.

  The present disclosure solves the above-described problem, and even in use in a cold region, particularly in an extremely cold region of −20 ° C. or lower, even if the blow-by gas leaked from the combustion chamber is blocked, the engine An object of the present invention is to provide a highly reliable and safe engine device in which the pressure in the crankcase of the device is prevented from suddenly rising and the lubricating oil inside the crankcase does not leak.

One aspect according to the present disclosure is an engine apparatus having a blow-by gas reduction mechanism that recirculates blow-by gas leaking from a combustion chamber to an intake pipe through which intake air flows.
A pressure adjusting unit having a blow-by gas passage through which the blow-by gas from the combustion chamber flows;
A reduction hose connected to the blow-by gas passage;
A blow-by gas mixing joint for introducing the blow-by gas flowing through the reduction hose into the intake pipe; and
The pressure adjusting unit includes a pressure adjusting valve that communicates the blow-by gas passage with the outside when the pressure in the blow-by gas passage exceeds a predetermined pressure.

  According to the present disclosure, even in cold regions, particularly in extremely cold regions where the outside air temperature is −20 ° C. or less, the blow-by gas pipes leaking from the combustion chamber, particularly, intake air (external air: fresh air) and blow-by gas A highly reliable and safe engine device in which the pressure in the crankcase is maintained at a desired pressure even if the pipe near the mixing area where it merges is icing and the pipe is blocked with ice. Can be provided.

The perspective view which shows the diesel engine of Embodiment 1 which concerns on this indication. The perspective view which shows the vicinity of the head cover which covers the upper surface part of the cylinder head in the diesel engine of Embodiment 1. FIG. The top view which looked at one part including the head cover in the diesel engine of Embodiment 1 from upper direction Sectional drawing which cut | disconnected the pressure adjustment part provided in the reduction | restoration hose in the diesel engine of Embodiment 1 along the flow direction of blow-by gas. Sectional drawing which cut | disconnected the pressure adjustment part in the VV line | wire in FIG. Sectional drawing which cut | disconnected the pressure adjustment part in the diesel engine of Embodiment 2 which concerns on this indication along the flow direction of blow-by gas. Sectional drawing which cut | disconnected the pressure adjustment part in the VII-VII line in FIG. The figure which shows schematic arrangement | positioning of the reduction | restoration hose which the blowby gas flows from the exhaust port of an engine main body to the blowby gas mixing joint in the diesel engine of Embodiment 3 which concerns on this indication. Schematic which shows the structure of the reduction | restoration hose in the diesel engine of Embodiment 3. FIG.

A first aspect according to the present disclosure is an engine apparatus having a blow-by gas reduction mechanism that recirculates blow-by gas leaking from a combustion chamber to an intake pipe through which intake air flows.
A pressure adjusting unit having a blow-by gas passage through which the blow-by gas from the combustion chamber flows;
A reduction hose connected to the blow-by gas passage;
A blow-by gas mixing joint for introducing the blow-by gas flowing through the reduction hose into the intake pipe; and
The pressure adjusting unit includes a pressure adjusting valve that communicates the blow-by gas passage with the outside when the pressure in the blow-by gas passage exceeds a predetermined pressure.

  The engine device according to the first aspect of the present disclosure configured as described above is a blow-by gas conduit leaking from a combustion chamber, particularly in a cold region, particularly in an extremely cold region where the outside air temperature is −20 ° C. or less. Even if the pipe near the mixing area where the intake air (external air: fresh air) and blow-by gas merge and icing and the pipe is blocked with ice, the pressure inside the engine body becomes the desired pressure. Maintained.

  In the engine device according to the second aspect of the present disclosure, the pressure adjusting unit according to the first aspect includes a storage portion below the blow-by gas passage, and the storage portion is blow-by passing through the blow-by gas passage. You may comprise so that the liquid component contained in gas may be collected. In the engine device according to the second aspect of the present disclosure configured as described above, liquid components such as moisture and / or oil contained in the blow-by gas introduced from the engine main body to the blow-by gas mixing joint in the blow-by gas passage. Because it is configured to be removed, for example, even in the use in extremely cold regions, icing of the pipeline in the mixing region of the intake air and blow-by gas in the blow-by gas mixing joint is suppressed, and unnecessary oil is removed. Is possible.

  An engine device according to a third aspect of the present disclosure is configured such that the pressure regulating valve according to the second aspect is configured to open an opening on the bottom surface of the reservoir by the weight of the liquid accumulated in the reservoir. May be. In the engine device according to the third aspect of the present disclosure thus configured, it is possible to automatically move liquid such as water and / or lubricating oil removed in the blow-by gas passage to another region. The maintenance management is easy.

  The engine apparatus of the 4th aspect which concerns on this indication may connect the said reduction | restoration hose in the said 1st aspect so that blowby gas may be introduced into the said blowby gas mixing joint from the downward direction. In the engine device according to the fourth aspect of the present disclosure thus configured, it is possible to store liquid components such as moisture and oil contained in the blow-by gas introduced from the engine body into the blow-by gas mixing joint. Become.

  In the engine device according to the fifth aspect of the present disclosure, the pressure adjusting unit according to the fourth aspect is disposed at a lowermost position in a path through which blow-by gas flows from the combustion chamber to the blow-by gas mixing joint. The liquid component contained in the blow-by gas may be discharged. In the engine device according to the fifth aspect of the present disclosure configured as described above, liquid components such as moisture and / or oil contained in the blow-by gas introduced from the engine body to the blow-by gas mixing joint with a simple configuration. It can be removed.

  Hereinafter, embodiments according to the present disclosure will be described with reference to the accompanying drawings. The configuration of the present invention is not limited by the configuration described in the following embodiments. In the engine device of the present disclosure, a diesel engine will be described as an example in the following embodiment, but the present invention is not limited to the configuration of the diesel engine in the embodiment, and the technical idea described in the embodiment. It includes an engine device configured based on an equivalent technical idea.

(Embodiment 1)
A diesel engine as an engine device of Embodiment 1 according to the present disclosure will be described with reference to the accompanying drawings. In the figure, the direction of the arrow UP will be described as the upward direction.

  FIG. 1 is a perspective view showing an overall configuration of a diesel engine 1 according to Embodiment 1 of the present disclosure. FIG. 2 is a perspective view showing the vicinity of the head cover that covers the upper surface portion of the cylinder head in the diesel engine 1 of the first embodiment, and a part thereof is shown in cross section. The diesel engine 1 according to the first embodiment includes a continuously regenerative exhaust gas purification device 2.

  The diesel engine 1 of the first embodiment is provided with a blow-by gas reduction mechanism 3 (see FIG. 2) that recirculates the blow-by gas in the crankcase leaking from the combustion chamber to the intake system (intake pipe). A blow-by gas reduction mechanism 3 is provided on a head cover 10 that covers an intake valve and an exhaust valve provided on an upper surface portion of a cylinder head of the diesel engine 1. The blow-by gas reduction mechanism 3 has a gas pressure adjusting unit 4 formed by partially bulging upward the upper surface of the head cover 10. A blow-by gas intake chamber 5 into which blow-by gas leaked from the combustion chamber of the diesel engine 1 and the like and a blow-by gas in the blow-by gas intake chamber 5 are supplied to the inside of the gas pressure adjusting unit 4 through a gas pressure adjusting valve. A blow-by gas expansion chamber 6 is formed. When a lubricating oil component accumulates in the blow-by gas expansion chamber 6 on the bottom surface of the blow-by gas expansion chamber 6, the check valve rotates by the weight of the lubricating oil component and drops the lubricating oil component to the upper surface side of the cylinder head. For example, a leaf spring that bends downward due to weight is provided. As described above, the lubricating oil component accumulated in the blow-by gas expansion chamber 6 falls to the upper surface side of the cylinder head and is collected in the diesel engine 1.

  In the configuration of the first embodiment, since a check valve, which is a leaf spring, is provided on the bottom surface of the blow-by gas expansion chamber 6, the lubricating oil scatters from the upper surface side of the cylinder head toward the check valve. However, the scattered lubricating oil is prevented from entering the blow-by gas expansion chamber 6.

  In the blow-by gas expansion chamber 6, for example, a plurality of partition plates are provided to form a plurality of labyrinth-like passages, and when the blow-by gas swells in the plurality of labyrinth-like passages, a lubricating oil component in the blow-by gas Is a configuration in which is removed. The removed lubricating oil component accumulates on the bottom surface of the blow-by gas expansion chamber 6, the leaf spring is bent by its own weight, falls to the upper surface side of the cylinder head, and is collected in the diesel engine.

  On the other hand, the blow-by gas from which the lubricating oil component has been removed in the blow-by gas expansion chamber 6 is introduced into the intake pipe via the conduit of the reduction hose 12 (see FIG. 2) connected to the exhaust port 11 of the blow-by gas expansion chamber 6. 13 (refer to FIG. 3 described later) is configured to be fed into the pipeline. An exhaust port 11 of the blow-by gas expansion chamber 6 is integrally formed with the head cover 10 and protrudes from the upper surface of the head cover 10.

  FIG. 3 is a plan view of a part of the diesel engine 1 including the head cover 10 as viewed from above, and a reduction hose 12 between the exhaust port 11 of the blow-by gas expansion chamber 6 formed in the head cover 10 and the intake pipe 13. The connection state is shown by.

  An intake pipe 13 shown in FIG. 3 is an intake pipe through which intake air (external air: fresh air) flows toward a supercharger (turbocharger) 7 via an air cleaner (not shown). In the pipe 13, the intake air flows from top to bottom. A blow-by gas mixing joint 20 for introducing blow-by gas from the blow-by gas expansion chamber 6 in the head cover 10 into the intake pipe 13 is provided on the pipe line of the intake pipe 13. The reduction hose 12 that connects the blow-by gas mixing joint 20 connected to the intake pipe 13 and the exhaust port 11 (valve arm chamber outlet) of the diesel engine body via a pressure adjusting unit 21 described later has heat resistance and cold resistance. It is made of a flexible material such as a rubber material.

  FIG. 4 is a cross-sectional view showing the pressure adjusting unit 21 provided in the reduction hose 12 that connects the exhaust port 11 of the engine body and the blow-by gas mixing joint 20, and is cut along the flow direction of the blow-by gas. It is a cross section. FIG. 5 is a cross-sectional view of the pressure adjusting unit 21 taken along the line VV in FIG.

  As shown in FIGS. 4 and 5, the pressure adjusting unit 21 has a blow-by gas passage 21 a that is a conduit for flowing blow-by gas exhausted from the exhaust port 11 (valve arm chamber outlet) to the reduction hose 12. Yes. That is, one end of the blow-by gas passage 21 a formed by the pressure adjustment unit 21 is connected to the exhaust port 11, and the other end of the blow-by gas passage 21 a is connected to the reduction hose joint 12 a provided at one end of the reduction hose 12. Yes. In the configuration of the first embodiment, the pressure adjusting unit 21 is bonded to the exhaust port 11 of the engine body and the end of the reduction hose joint 12a by a joining means 24, for example, a band, sealed with a sealing material, and screwed. Joined by fixing with an adhesive or the like.

  The blow-by gas sent to the reduction hose 12 from the blow-by gas passage 21 a of the pressure adjusting unit 21 is mixed with the intake air from the intake pipe 13 in the blow-by gas mixing joint 20. The blow-by gas mixing joint 20 has a three-way joint structure, and has a structure in which a blow-by gas inlet is provided in an intake passage connected to a pipe line of the intake pipe 13. The other end of the reduction hose 12 is connected to the blow-by gas inlet. The blow-by gas mixing joint 20 is provided with a temperature sensor 14 to detect the intake air temperature in the intake passage of the blow-by gas mixing joint 20.

  As described above, the pressure adjusting unit 21 provided in the diesel engine 1 according to the first embodiment is configured to flow the blow-by gas exhausted from the exhaust port 11 that is the blow-by gas outlet from the engine body to the reduction hose 12. The blow-by gas passage 21a is formed with a pressure adjusting hole 21b that can communicate with the outside. In FIG. 4, the pressure adjustment hole 21b is formed above the blow-by gas passage 21a, and the upper end of the pressure adjustment hole 21b is opened. The pressure adjusting unit 21 is provided with a pressure adjusting valve 22 that closes the upper end opening of the pressure adjusting hole 21b in a normal state. In the diesel engine 1 of the first embodiment, a leaf spring that starts to bend when a predetermined pressure is received is used as the pressure regulating valve 22. The predetermined pressure in the first embodiment is set within a range of 5 kPa to 8 kPa, for example, 5 kPa.

  In the first embodiment, the pressure regulating valve 22 is configured such that the upper end opening of the pressure regulating hole 21b is closed in an airtight state by the pressure regulating valve 22 that is a leaf spring in a normal state in which the inside of the blow-by gas passage 21a is equal to or lower than a predetermined pressure. It is. In the first embodiment, an example in which a leaf spring is used as the pressure regulating valve 22 and a screw is used as the fixing means 23 will be described. However, the present disclosure is not limited to such a configuration. In other words, the blow-by gas passage 21a may be opened when the inside of the blow-by gas passage 21a becomes equal to or higher than a predetermined pressure.

  Hereinafter, the operation of the pressure adjusting unit 21 in the diesel engine 1 of the first embodiment configured as described above will be described.

  As described above, in the configuration of the first embodiment, the supercharger 7 (see FIG. 3) is provided on the downstream side of the blow-by gas mixing joint 20 connected to the intake pipe 13 through which intake air flows. For this reason, the inside of the blow-by gas passage 21a of the pressure adjusting unit 21 connected to the blow-by gas mixing joint 20 via the reduction hose 12 is in a negative pressure state. Therefore, the blow-by gas discharged from the exhaust port 11 of the engine body flows through the blow-by gas passage 21 a of the pressure adjusting unit 21 and flows to the blow-by gas mixing joint 20 via the reduction hose 12.

  In the normal state where the blow-by gas flows as described above, the blow-by gas from the exhaust port 11 of the engine main body passes through the pressure adjusting unit 21 and the reduction hose 12 and is introduced into the blow-by gas mixing joint 20 so that the blow-by gas and the intake air are introduced. Are mixed and sucked into the supercharger 7. In such a normal state, the blow-by gas passage 21a is in a negative pressure state in the pressure adjusting unit 21, and the leaf spring as the pressure adjusting valve 22 does not operate.

  For example, when the diesel engine 1 of the first embodiment is used as a power source in an extremely cold region (for example, the outside air temperature is −20 ° C.), when the blowby gas and the intake air are mixed in the blowby gas mixing joint 20, Moisture contained in the gas instantly freezes due to the intake air (for example, the intake air temperature is −20 ° C.), and a phenomenon occurs in which the tube wall near the mixed region of the blow-by gas and the intake air is icing. If the ice icing on the pipe wall closes the pipe, the reducing hose 12, which is the blow-by gas pipe upstream from the closed position, the blow-by gas passage 21a of the pressure adjusting unit 21, the crank of the engine body The internal pressure inside the case increases. At this time, when the internal pressure of the blow-by gas passage 21a of the pressure adjusting unit 21 reaches a predetermined pressure (for example, 5 kPa), the leaf spring that is the pressure adjusting valve 22 starts to bend, and the upper end opening of the pressure adjusting hole 21b is opened. Opened. As a result, the blow-by gas in the blow-by gas passage 21a of the pressure adjusting unit 21 is released to the outside, and the internal pressure of the crankcase decreases. Accordingly, it is possible to reliably prevent a problem that the pressure in the crankcase abnormally increases and the engine oil in the crankcase leaks.

  As described above, for example, even when the pipeline near the mixed region of blow-by gas and intake air is blocked by ice, the leaf spring that is the pressure regulating valve 22 in the pressure regulating unit 21 functions to regulate the pressure. Thus, the pressure in the blow-by gas pipe upstream of the closed pipe does not increase, and the pressure inside the crankcase is kept below a predetermined pressure. In addition, when the pipe line closed by freezing is communicated due to an increase in temperature, a heating process of the frozen part, or the like, the inside of the pipe line becomes a predetermined pressure or lower, so that the leaf spring which is the pressure adjustment valve 22 of the pressure adjustment unit 21 Returns to the normal state, and the upper end opening of the pressure adjusting hole 21b is hermetically closed.

  In the configuration of the first embodiment, the pressure adjustment unit 21 will be described as being directly connected to the exhaust port 11 of the engine body, and the pressure adjustment valve 22 of the pressure adjustment unit 21 is provided in the vicinity of the exhaust port 11 of the engine body. ing. In a passage where blow-by gas flows from the engine body (valve arm chamber) to the blow-by gas mixing joint 20, the pressure adjusting unit 21 is a position where the temperature of the blow-by gas does not freeze even when the temperature of the blow-by gas is high and the outside air temperature is low. That is, it is preferable to provide it as close as possible to the valve arm chamber of the engine body.

  The engine device according to the first embodiment of the present disclosure configured as described above includes a blow-by gas and intake air (outside air) leaking from the combustion chamber even in a cold region, particularly in an extremely cold region of −20 ° C. or lower. Even if the pipe in the mixing area is blocked by icing, the pressure inside the crankcase is maintained at a predetermined pressure, and the lubricating oil inside the crankcase does not leak out. It becomes a high engine device.

(Embodiment 2)
Next, a diesel engine as an engine apparatus according to Embodiment 2 of the present disclosure will be described focusing on differences from Embodiment 1 described above. In the diesel engine of the second embodiment, the difference from the configuration of the first embodiment is the configuration of the pressure adjusting unit, and the other configurations are the same as those of the first embodiment. Therefore, in the description of the second embodiment, elements having the same functions, configurations, and functions as those of the first embodiment are denoted by the same reference numerals, and detailed descriptions of the elements having the same reference numerals are omitted. To do.

  FIG. 6 is a cross-sectional view showing the pressure adjusting unit 25 in the diesel engine 1 according to the second embodiment of the present disclosure, which is a cross section cut along the flow direction of blow-by gas. 7 is a cross-sectional view of the pressure adjusting unit 25 taken along the line VII-VII in FIG.

  As shown in FIGS. 6 and 7, the pressure adjusting unit 25 has a blow-by gas passage 25 a that is a conduit for flowing blow-by gas exhausted from the exhaust port 11 of the engine body to the reduction hose 12. That is, one end of the blow-by gas passage 25a formed by the pressure adjustment unit 25 in the second embodiment is connected to the exhaust port 11 of the engine body, and the other end of the blow-by gas passage 25a is connected to one end of the reduction hose 12. It is connected to the provided reduction hose joint 12a. In the configuration of the second embodiment, the pressure adjustment unit 25 is joined to the exhaust port 11 of the engine body and the end of the reduction hose joint 12a by a joining means 24, for example, a band, sealed with a sealing material, and screwed. Joined by fixing with an adhesive or the like.

  The blowby gas sent to the reduction hose 12 from the blowby gas passage 25a of the pressure adjusting unit 25 is mixed with the intake air from the intake pipe 13 in the blowby gas mixing joint 20 (see FIG. 3).

  As described above, the pressure adjusting unit 25 provided in the diesel engine 1 according to the second embodiment is configured to flow the blow-by gas exhausted from the exhaust port 11 that is the blow-by gas outlet from the engine body to the reduction hose 12. Blow-by gas passage 25a is provided. A storage portion 25c as a space is formed below the blow-by gas passage 25a. A pressure adjusting hole 25b that can communicate with the outside is formed on the bottom surface of the reservoir 25c. That is, the pressure adjustment hole 25b is formed below the blow-by gas passage 25a, and the lower end of the pressure adjustment hole 25b is opened. The pressure adjusting unit 25 is provided with a pressure adjusting valve 26 that closes the lower end opening of the pressure adjusting hole 25b in a normal state. In the diesel engine 1 of the second embodiment, a leaf spring that starts to bend when a predetermined pressure is received is used as the pressure regulating valve 26. The predetermined pressure in the second embodiment is set within a range of 5 kPa to 8 kPa, for example, 5 kPa.

  In the pressure regulating valve 26 according to the second embodiment, the lower end opening of the pressure regulating hole 25b is closed in an airtight state by the pressure regulating valve 26, which is a leaf spring, in the normal state where the inside of the blow-by gas passage 25a is equal to or lower than a predetermined pressure. It is configured. In the second embodiment, a configuration example in which a leaf spring is used as the pressure regulating valve 26 and a screw is used as the fixing means 27 will be described. However, the present disclosure is limited to such a configuration. Instead, the blow-by gas passage 25a may be opened when the inside of the blow-by gas passage 25a reaches a predetermined pressure or higher.

  Hereinafter, the operation of the pressure adjustment unit 25 in the diesel engine 1 of the second embodiment configured as described above will be described.

  Similar to the configuration of the first embodiment described above, the inside of the blow-by gas passage 25a of the pressure adjusting unit 25 in the second embodiment is in a negative pressure state. Accordingly, the blow-by gas from the exhaust port 11 of the engine body passes through the blow-by gas passage 25a of the pressure adjusting unit 25 and flows to the blow-by gas mixing joint 20 via the reduction hose 12.

  In the normal state where the blow-by gas flows as described above, the blow-by gas discharged from the exhaust port 11 of the engine body passes through the pressure adjusting unit 25 and the reduction hose 12 and is introduced into the blow-by gas mixing joint 20 to be blow-by gas. And the intake air are mixed and sucked into the supercharger 7 (see FIG. 3). Thus, in the normal state where blow-by gas flows, the blow-by gas passage 25a is in a negative pressure state in the pressure adjusting unit 25, and the leaf spring as the pressure adjusting valve 26 does not operate.

  For example, when the diesel engine 1 of the second embodiment is used as a power source in an extremely cold region (for example, the outside air temperature is −20 ° C.), when the blowby gas and the intake air are mixed in the blowby gas mixing joint 20, Moisture contained in the gas instantly freezes due to the intake air (for example, the intake air temperature is −20 ° C.), and a phenomenon occurs in which the tube wall near the mixed region of the blow-by gas and the intake air is icing. If the ice icing on the pipe wall closes the pipe, the reducing hose 12 which is the blow-by gas pipe upstream from the closed position, the blow-by gas passage 25a of the pressure adjusting unit 25, the crank of the engine body The internal pressure inside the case increases. At this time, when the internal pressure of the blow-by gas passage 25a of the pressure adjusting unit 25 reaches a predetermined pressure (for example, 5 kPa), the leaf spring which is the pressure adjusting valve 26 starts to bend, and the lower end opening of the pressure adjusting hole 25b is opened. Opened. As a result, the blow-by gas in the blow-by gas passage 25a of the pressure adjusting unit 25 is released to the outside, and the internal pressure of the crankcase decreases. Therefore, in the configuration of the second embodiment, it is possible to reliably prevent a problem that the pressure in the crankcase abnormally increases and the engine oil inside the crankcase leaks.

  Furthermore, in the configuration of the second embodiment, the pressure adjusting unit 25 has a storage unit 25c below the blow-by gas passage 25a. The blow-by gas discharged from the exhaust port 11 of the engine body contains moisture. The blow-by gas discharged from the exhaust port 11 of the engine body is rapidly cooled by the pressure adjusting unit 25 particularly when the outside air temperature is low. For this reason, in the pressure adjustment part 25, the water | moisture content of blow-by gas liquefies and it accumulates in the storage part 25c which exists under the blow-by gas channel | path 25a.

  In the reservoir 25c, the leaf spring as the pressure adjustment valve 26 is bent by the dead weight of the accumulated water, the lower end opening of the pressure adjustment hole 25b is opened, and the water in the reservoir 25c is released. Thus, in the configuration of the second embodiment, for example, when ice closes the pipeline through which the blow-by gas flows, the blow-by gas pipeline upstream of the closed position is opened and mixed with the intake air. Reducing the moisture in the blow-by gas, reducing the formation amount and formation speed of ice formed when the blow-by gas is mixed with the intake air, and the pipe line near the mixing region where the blow-by gas is mixed with the intake air. It is reduced from being closed by ice.

  As described above, for example, even when the pipe line near the mixed region of blow-by gas and intake air is blocked by ice, the leaf spring that is the pressure adjustment valve 26 in the pressure adjustment unit 25 functions to adjust the pressure. As a result, the pressure in the blow-by gas pipe upstream of the closed pipe does not increase, and the pressure inside the crankcase is kept below a predetermined pressure. In addition, when the pipe line closed by freezing is communicated due to an increase in temperature, a heating process of the frozen part, or the like, the inside of the pipe line becomes a predetermined pressure or lower, so that the plate that is the pressure regulating valve 26 of the pressure regulating unit 25 The spring returns to the state where the lower end opening of the pressure adjusting hole 25b is closed in an airtight manner.

  In the configuration of the second embodiment, the pressure adjustment unit 25 is described as being connected directly to the exhaust port 11 of the engine body, and the pressure adjustment valve 26 of the pressure adjustment unit 25 is provided in the vicinity of the exhaust port 11 of the engine body. ing. In the passage where blow-by gas flows from the engine body (valve arm chamber) to the blow-by gas mixing joint 20, the pressure adjustment unit 25 is a position where the temperature of the blow-by gas does not freeze even when the temperature of the blow-by gas is high and the outside air temperature is low. That is, it is preferable to provide it as close as possible to the valve arm chamber of the engine body.

  The engine device according to the second embodiment of the present disclosure configured as described above includes a blow-by gas and intake air (outside air) leaking from the combustion chamber even in a cold region, particularly in an extremely cold region of −20 ° C. or lower. The ice in the pipe line in the vicinity of the mixing region can be suppressed from being closed, and even if the pipe line is blocked by icing, the pressure in the crankcase is maintained at a predetermined pressure. This makes the engine device highly reliable and safe without leakage of the internal lubricating oil.

(Embodiment 3)
Next, a diesel engine as an engine device of Embodiment 3 according to the present disclosure will be described focusing on differences from Embodiment 1 described above. In the diesel engine of the third embodiment, the difference from the configuration of the first embodiment is the configuration of a reduction hose through which blow-by gas flows from the engine body to the blow-by gas mixing joint, and other configurations are the same as those of the first embodiment. Is the same. Therefore, in the description of the third embodiment, elements having the same functions, configurations, and functions as those of the first embodiment are denoted by the same reference numerals, and detailed descriptions of the elements having the same reference numerals are omitted. .

  FIG. 8 is a diagram illustrating a schematic arrangement of reducing hoses through which blow-by gas flows from the exhaust port of the engine body to the blow-by gas mixing joint in the diesel engine 1 according to Embodiment 3 of the present disclosure. FIG. 9 is a diagram illustrating a configuration of a reduction hose in the diesel engine 1 according to the third embodiment.

  As shown in FIG. 8, the reduction hose 30 in the diesel engine 1 of the third embodiment is an upstream reduction hose arranged downward so as to flow downward from the exhaust port 11 (see FIG. 3) of the engine body. 12A and a downstream side reduction hose 12B for flowing blow-by gas to the blow-by gas mixing joint 20 (see FIG. 3) via the reduction hose intermediate connecting portion 29. That is, in the reduction hose 30, the reduction hose intermediate connection portion 29 is disposed at the lowermost position, and the upstream reduction hose 12A and the downstream reduction hose 12B are led out upward from the reduction hose intermediate connection portion 29. It is installed. Further, a discharge pipe 32 is provided from the reduction hose intermediate connecting portion 29 toward the oil pan. In the configuration of the third embodiment, the reduction hose intermediate connecting portion 29 has the function of the pressure adjusting portion in the first and second embodiments.

  As shown in FIG. 9, a substantially U-shaped blow-by gas passage 28 is formed in the reduction hose intermediate connecting portion 29, and the upstream-side reduction hose 12 </ b> A and the downstream-side reduction hose are formed at respective ends of the blow-by gas passage 28. Each hose 12B is connected. An opening is formed in the lowermost end portion of the reduction hose intermediate connecting portion 29, and a pressure regulating valve 31, for example, a leaf spring is provided so as to close the opening. The pressure regulating valve 31 in the third embodiment has the same function as the pressure regulating valve (22, 26) of the pressure regulating section (21, 25) in the above-described embodiment, and blow-by gas from the engine body is When the pressure is higher than the pressure set in the flowing reduction hose (for example, a pressure of 5 kPa or more), the reduction hose has a function of communicating with the outside.

  Further, in the reduction hose intermediate connecting portion 29, since blow-by gas from the engine body toward the blow-by gas mixing joint 20 flows through the substantially U-shaped blow-by gas passage 28, the lower end portion of the blow-by gas passage 28 is included in the blow-by gas. Reservoir 28a is formed so that the accumulated moisture is accumulated. Therefore, the pressure regulating valve 31 is disposed on the bottom surface of the reservoir 28a. The leaf spring that is the pressure regulating valve 31 bends due to the weight of the water accumulated in the reservoir 28 a, and the opening at the lowermost end portion of the reducing hose intermediate connecting portion 29 is opened. As a result, the water accumulated in the reservoir 28 a is discharged from the discharge pipe 32 connected to the opening to the oil pan below the diesel engine 1.

  The engine device according to the third embodiment of the present disclosure configured as described above includes blow-by gas and intake air (external air) leaking from the combustion chamber even in a cold region, particularly in an extremely cold region of −20 ° C. or lower. The ice in the pipe line in the vicinity of the mixing region can be suppressed from being closed, and even if the pipe line is blocked by icing, the pressure in the crankcase is maintained at a predetermined pressure. This makes the engine device highly reliable and safe without leakage of the internal lubricating oil.

  As described above, in the engine device of the present disclosure, the blow-by gas reduction mechanism that recirculates the blow-by gas in the crankcase leaking from the combustion chamber to the intake system is provided, and the pressure adjustment mechanism is provided in the blow-by gas reduction mechanism. Provided. Thus, by providing the pressure adjustment mechanism in the blow-by gas reduction mechanism, for example, even when the engine device of the present disclosure is used as a power source in a cold region or a very cold region, it is included in the blow-by gas in the blow-by gas mixing joint. Even if the water freezes and the pipe is closed, the pressure in the engine body is maintained at a predetermined pressure, and the engine device is highly reliable and safe without leakage of lubricating oil.

  It should be noted that, by appropriately combining arbitrary configurations among the configurations described in the above embodiments, the excellent effects of each can be achieved.

  Although the present disclosure has been fully described in connection with preferred embodiments with reference to the accompanying drawings, various variations and modifications will be apparent to those skilled in the art. Such changes and modifications are to be understood as included within the scope of the present disclosure as set forth in the appended claims.

  The present disclosure is used for an engine device such as a diesel engine mounted as a power source in various power devices such as a work vehicle, an agricultural machine, a generator, and a refrigerator, and particularly in an engine device used in a cold region or a very cold region. Useful.

1 Diesel engine (engine equipment)
DESCRIPTION OF SYMBOLS 10 Head cover 11 Engine exhaust port 12, 30 Reduction hose 12a Reduction hose joint 12A Upstream reduction hose 12B Downstream reduction hose 13 Intake pipe 14 Temperature sensor 20 Blow-by gas mixing joint 21, 25 Pressure adjustment part 21a, 25a Blow-by gas Passage 21b, 25b Pressure adjustment hole 22, 26, 31 Pressure adjustment valve 23, 27 Fixing means 24 Joining means 25c, 28a Storage part 26 Pressure adjustment valve 28 Blow-by gas passage 29 Reduction hose intermediate connection part 32 Discharge pipe

Claims (5)

In an engine apparatus having a blow-by gas reduction mechanism for recirculating blow-by gas leaking from a combustion chamber to an intake pipe through which intake air flows,
A pressure adjusting unit having a blow-by gas passage through which the blow-by gas from the combustion chamber flows;
A reduction hose connected to the blow-by gas passage;
A blow-by gas mixing joint for introducing the blow-by gas flowing through the reduction hose into the intake pipe; and
The said pressure adjustment part is an engine apparatus comprised by having connected the said blow-by gas passage with the exterior and having a pressure adjustment valve, when the pressure in the said blow-by gas passage exceeds predetermined pressure.   2. The engine according to claim 1, wherein the pressure adjusting unit includes a storage part below the blow-by gas passage, and the storage part stores liquid contained in blow-by gas passing through the blow-by gas passage. apparatus.   The engine device according to claim 2, wherein the pressure adjusting valve is configured to open an opening on a bottom surface of the storage portion by a dead weight of liquid stored in the storage portion.   The engine device according to claim 1, wherein the reduction hose is connected to the blow-by gas mixing joint so as to introduce blow-by gas from below.   The pressure adjusting unit is disposed at a lowermost position in a path through which blow-by gas flows from the combustion chamber to the blow-by gas mixing joint, and is configured to discharge a liquid component contained in the blow-by gas. The engine device described.

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