JP6051154B2 - diesel engine - Google Patents

Description

  The present invention relates to a diesel engine, and more particularly to a diesel engine in which an engine body, a DPF case, and an SCR catalyst case can be arranged in a compact manner.

  Conventionally, a diesel engine includes an engine body, a DPF case, and an SCR catalyst case. The DPF case contains a DPF, and the SCR catalyst case contains an SCR catalyst (see, for example, Patent Document 1). .

  According to this type of engine, there is an advantage that PM in exhaust gas can be captured by the DPF and NOx in exhaust gas can be reduced by the SCR catalyst.

  However, in the thing of patent document 1, since an engine main body, a DPF case, and an SCR catalyst case are arrange | positioned separately, there exists a problem.

JP 2011-32946 A (see FIG. 1)

<< Problem >> The engine body, the DPF case, and the SCR catalyst case cannot be arranged compactly.
In the thing of patent document 1, since an engine main body, a DPF case, and an SCR catalyst case are arrange | positioned separately, an engine main body, a DPF case, and an SCR catalyst case cannot be arrange | positioned compactly.

  The subject of this invention is providing the diesel engine which can arrange | position an engine main body, a DPF case, and an SCR catalyst case compactly.

Invention specific matters of the invention according to claim 1 are as follows.
As illustrated in FIGS. 1 to 3, an engine body (1), a DPF case (2), and an SCR catalyst case (3) are provided.
In the diesel engine in which the DPF case (2) contains the DPF (4) and the SCR catalyst case (3) contains the SCR catalyst (5),
DPF case (2) and SCR catalyst case (3) are mounted on the engine body (1).
As illustrated in FIG. 1 to FIG. 3, a DPF support base (10) and a pair of SCR support stays (11) and (11) are provided.
The DPF support (10) is provided at the upper part of the flywheel housing (6), and the flywheel housing (6) is a casting disposed at the end of the cylinder block (12). The DPF support (10) The DPF case (2) is mounted on the DPF support (10), and is formed by the built-up portion of the cast flywheel housing (6).
The pair of SCR support stays (11) and (11) is a casting, and each lower part is fixed to a flywheel housing (6) including a DPF support (10), and an SCR catalyst case (3) is supported on each upper part. The parts (3b) and (3c) are placed and fixed,
As illustrated in FIG. 1, the SCR catalyst case (3) is oriented in a direction along the longitudinal direction of the DPF case (2),
As shown in FIGS. 1 to 5A, the DPF case (2) is a flywheel with the crankshaft central axis (19) extending in the front-rear direction and the flywheel housing (6) side as the rear side. Located directly above the wheel housing (6) and directly behind the cylinder head cover (7),
A pair of SCR support stays (11), (11) covers the DPF case (2) from both ends thereof, and the SCR catalyst case (3) is supported by the pair of SCR support stays (11), (11). Is a diesel engine, which is arranged directly above the DPF case (2).

(Invention of Claim 1)
The invention according to claim 1 has the following effects.
<Effect> The engine body, the DPF case, and the SCR catalyst case can be arranged in a compact manner.
As illustrated in FIGS. 1 to 3, since the DPF case (2) and the SCR catalyst case (3) are mounted on the engine body (1), the engine body (1), the DPF case (2), and the SCR The catalyst case (3) can be arranged compactly.

<Effect> Easier to install on engine-equipped machines.
As illustrated in FIGS. 1 to 3, since the DPF case (2) and the SCR catalyst case (3) are mounted on the engine body (1), the engine body (1) can be mounted on an engine-equipped machine. The DPF case (2) and the SCR catalyst case (3) are also collectively mounted on the engine-equipped machine, and can be easily mounted on the engine-equipped machine.

<Effect> The DPF case and the SCR catalyst case can be firmly supported by the engine body.
As illustrated in FIGS. 1 to 3, the DPF support (10) is provided on the top of the flywheel housing (6), and the flywheel housing (6) is disposed at the end of the cylinder block (12). Since the DPF support base (10) is a casting, it is formed by the built-up part of the flywheel housing (6) by casting, and the DPF case (2) is mounted on the DPF support base (10). The DPF case (2) can be firmly supported by the engine body (1) by the DPF support (10) having high rigidity.
Further, the pair of SCR support stays (11) and (11) are cast, and each lower part is fixed to a flywheel housing (6) including a DPF support base (10), and an SCR catalyst case (3) is provided on each upper part. Since the supported portions (3b) and (3c) are placed and fixed, the SCR catalyst case (3) is provided with a highly rigid DPF support base via a pair of highly rigid SCR support stays (11) and (11). Supported by (10), the SCR catalyst case (3) can be firmly supported by the engine body (1).

<Effect> The engine body, the DPF case, and the SCR catalyst case can be arranged in a compact manner.
As illustrated in FIG. 1, since the SCR catalyst case (3) is oriented in the direction along the longitudinal direction of the DPF case (2), the SCR catalyst case (3) does not intersect the DPF case (2). The engine body (1), the DPF case (2), and the SCR catalyst case (3) can be arranged in a compact manner.

<Effect> The engine body, the DPF case, and the SCR catalyst case can be arranged in a compact manner.
As illustrated in FIGS. 1 to 5A, the DPF case (2) is disposed directly above the flywheel housing (6) and directly behind the cylinder head cover (7), and the SCR catalyst case (3) is Because it is arranged directly above the DPF case (2), the engine body (1), the DPF case (2), and the SCR catalyst case (3) can be made compact by making effective use of the empty space in the engine body (1). Can be arranged.
<Effect> DPF regeneration efficiency is high.
As illustrated in FIG. 1 to FIG. 5 (A), since the DPF case (2) is covered from both ends by the pair of SCR support stays (11) and (11), the DPF case (2) is separated from the DPF case (2). Heat dissipation is limited by the SCR support stays (11) and (11), the DPF (4) is maintained at a high temperature, and the regeneration efficiency of the DPF (4) that incinerates and removes PM by exhaust heat is high.

(Invention of Claim 2 )
The invention according to claim 2 has the following effect in addition to the effect of the invention according to claim 1 .
<Effect> The straight pipe portion of the exhaust relay pipe, the DPF case, and the SCR catalyst case can be arranged in a compact manner.
As illustrated in FIG. 4, the straight pipe portion (14a) of the exhaust relay pipe (14) is oriented in the direction along the longitudinal direction of the DPF case (2) and the SCR catalyst case (3). The straight pipe portion (14a) of the relay pipe (14) does not intersect the DPF case (2) and the SCR catalyst case (3), and the straight pipe section (14a) of the exhaust relay pipe (14) and the DPF case (2) The SCR catalyst case (3) can be arranged compactly.

(Invention of Claim 3 )
The invention according to claim 3 has the following effect in addition to the effect of the invention according to claim 2 .
<Effect> It is possible to suppress the problem of urea water crystals sticking in the straight pipe portion.
As illustrated in FIG. 9, the straight pipe portion (14 a) of the exhaust relay pipe (14) is disposed in front of the lower part of the SCR catalyst case (3) and directly above the cylinder head cover (7). Overheating of the straight pipe part (14a) due to heat radiation from the DPF case (2) can be prevented, and a problem that the urea water (18) crystals are stuck in the straight pipe part (14a) can be suppressed.

<Effect> The engine height can be kept low.
As illustrated in FIG. 9, the straight pipe portion (14 a) of the exhaust relay pipe (14) is disposed in front of the lower part of the SCR catalyst case (3) and directly above the cylinder head cover (7). The straight pipe portion (14a) of the exhaust relay pipe (14) does not jump out to the upper side of the SCR catalyst case (3), and the height of the engine can be kept low.

(Invention of Claim 4 )
The invention according to claim 4 has the following effect in addition to the effect of the invention according to claim 2 or claim 3 .
<Effect> Distortion of each part such as piping can be prevented.
As illustrated in FIGS. 8 and 9, slip joint portions (17) and (17) are provided, and the slip joint portions (17) are disposed at both ends of the exhaust relay pipe (14), as illustrated in FIG. 10. The pipe portions (17a) and (17b) are fitted so as to be extendable and slidable in the axial direction, and the pipe portions (17a and 17b) are fixed at a predetermined extension and slide position by the fastening portion (17c). After the DPF case (2) and the SCR catalyst case (3) are mounted on the engine body (1), once the slip joint (17) is loosened, it is twisted or misaligned. Stress generated in each part such as piping can be released, and distortion of each part such as piping can be prevented.

(Invention according to claim 5 )
The invention according to claim 5 has the following effects in addition to the effects of the invention according to any one of claims 2 to 4 .
<Effect> An increase in exhaust pressure can be suppressed.
The structure of the exhaust lead-out pipe (2a) of the DPF case (2), the exhaust introduction pipe (3a) of the SCR catalyst case (3), and the exhaust relay pipe (14) illustrated in FIG. The exhaust (15) can be passed through the SCR catalyst case (3) with little resistance, and an increase in exhaust pressure can be suppressed.

(Invention of Claim 6 )
The invention according to claim 6 has the following effects in addition to the effects of the inventions according to claims 1 to 5 .
<Effect> Support for the SCR catalyst case can be strengthened.
As illustrated in FIG. 1, an X-shaped reinforcing member (28) is provided, and each upper end portion of the reinforcing member (28) is fixed to a pair of SCR support stays (11) and (11). Since each lower end is fixed to the DPF support base (10), the SCR support stays (11) and (11) are reinforced with the reinforcing material (28), so that the support of the SCR catalyst case (3) can be strengthened. it can.

It is a rear view of the diesel engine which concerns on embodiment of this invention. It is a right view of the engine of FIG. It is a left view of the engine of FIG. It is a top view of the engine of FIG. 5A is a partially longitudinal rear view of the engine of FIG. 1, and FIG. 5B is a longitudinal rear view of the exhaust relay pipe. It is a partial cross-sectional top view of the engine of FIG. It is the perspective view which looked down at the engine of FIG. 1 from back upper right. It is the perspective view which looked down at the engine of Drawing 1 from the front upper right. It is the perspective view which looked down at the engine of Drawing 1 from front upper left. It is a principle explanatory view of the slip joint part used with the engine of FIG.

  1 to 10 are diagrams for explaining a diesel engine according to an embodiment of the present invention. In this embodiment, a vertical in-line multi-cylinder diesel engine will be described.

The outline of the engine is as follows.
As shown in FIG. 2, the cylinder head (20) is assembled to the upper part of the cylinder block (12), and the cylinder head cover (7) is assembled to the upper part of the cylinder head (20). A gear case (21) is assembled, a flywheel housing (6) is assembled to the rear of the cylinder block (12), and an oil pan (23) is assembled to the lower part of the cylinder block (12).
As shown in FIG. 2, an intake manifold (24) is assembled on one side of the cylinder head (20), and an exhaust manifold (25) is assembled on the other side as shown in FIG. .

As shown in FIGS. 1-3, the engine main body (1), the DPF case (2), and the SCR catalyst case (3) are provided.
The DPF case (2) contains the DPF (4), and the SCR catalyst case (3) contains the SCR catalyst (5).
A DPF case (2) and an SCR catalyst case (3) are mounted on the engine body (1).

  As shown in FIG. 1, in the DPF case (2), the DOC (26) is accommodated on the upstream side, and the DPF (4) is accommodated on the downstream side. DPF is an abbreviation for diesel particulate filter, and DOC is an abbreviation for diesel oxidation catalyst. In the SCR catalyst case (3), the SCR catalyst (5) is accommodated on the upstream side, and the oxidation catalyst (27) is accommodated on the downstream side to prevent ammonia slip. SCR is an abbreviation for selective catalytic reduction. As shown in FIG. 6, the exhaust lead-out pipe (22c) of the supercharger (22) is connected to the exhaust lead-in pipe (2c) of the DPF (2).

As shown in FIGS. 1 to 3, a DPF support base (10) and a pair of SCR support stays (11) and (11) are provided.
The DPF support (10) is provided at the upper part of the flywheel housing (6), and the flywheel housing (6) is a casting disposed at the end of the cylinder block (12). The DPF support (10) The DPF case (2) is mounted and mounted on the DPF support (10).
The flywheel housing (6) is attached to the rear end of the cylinder block (12), and a transmission case (not shown) is connected to the rear side of the flywheel housing (6). The wheel housing (6) and the transmission case are used as a main frame of a traveling machine body such as a tractor.
The pair of SCR support stays (11) and (11) is a casting, and each lower part is fixed to a flywheel housing (6) including a DPF support (10), and an SCR catalyst case (3) is supported on each upper part. The parts (3b) and (3c) are placed and fixed.

The DPF case (2) is mounted on the DPF base bracket (8), and the DPF base bracket (8) is mounted on the DPF support (10). That is, the DPF case (2) is mounted on the DPF support base (10) via the DPF base bracket (8).
The supported portions (3b) and (3c) of the SCR catalyst case (3) are supported brackets provided on the SCR catalyst case (3).

As shown in FIG. 1, the SCR catalyst case (3) is oriented in a direction along the longitudinal direction of the DPF case (2).
As shown in FIGS. 1 to 5A, the DPF case (2) is a flywheel with the crankshaft central axis (19) extending in the front-rear direction and the flywheel housing (6) side as the rear side. Located just above the wheel housing (6) and just behind the cylinder head cover (7).
A pair of SCR support stays (11), (11) covers the DPF case (2) from both ends thereof, and the SCR catalyst case (3) is supported by the pair of SCR support stays (11), (11). Is disposed directly above the DPF case (2).

As shown in FIGS. 5 and 6, the pair of SCR support stays (11) and (11) are formed in a U-shape in both a longitudinal section and a transverse section.
As shown in FIG. 2, the SCR catalyst case (3) includes a front lead-out stay (9) led out forward, and the front lead-out stay (9) passes through the front support stay (29) through the cylinder head (20). ). Thereby, the back-and-forth swing of the SCR catalyst case (3) is suppressed.

As shown in FIG. 4, an exhaust outlet pipe (2a) of the DPF case (2), an exhaust introduction pipe (3a) of the SCR catalyst case (3), and an exhaust relay pipe (14) are provided.
The exhaust relay pipe (14) is interposed between the exhaust outlet pipe (2a) of the DPF case (2) and the exhaust introduction pipe (3a) of the SCR catalyst case (3), and is a straight pipe of the exhaust relay pipe (14). In the section (14a), the exhaust (15) derived from the DPF case (2) and the urea water (18) injected from the urea water injector (16) are mixed.
The straight pipe portion (14a) of the exhaust relay pipe (14) is oriented in the direction along the longitudinal direction of the DPF case (2) and the SCR catalyst case (3).
As shown in FIG. 5 (B), a mixer plate (30) is provided in the straight pipe portion (14a) of the exhaust relay pipe (14) to mix the exhaust (15) and the urea water (18). Promotion is planned.

  As shown in FIG. 9, the straight pipe portion (14 a) of the exhaust relay pipe (14) is disposed directly above the cylinder head cover (7) in front of the lower part of the SCR catalyst case (3).

As shown in FIGS. 8 and 9, slip joint portions (17) and (17) are provided, and the slip joint portions (17) are arranged at both ends of the exhaust relay pipe (14).
As shown in FIG. 10, in principle, the slip joint portion (17) is fitted so that the pipe portions (17a) and (17b) can be expanded and contracted in the axial length direction, and the fastening portion (17c) allows a predetermined amount. The pipe portions (17a) and (17b) are configured to be fixed at the telescopic sliding position. The slip joint portion (17) is fitted so that the pipe portions (17a) and (17b) can rotate and slide in the circumferential direction, and the pipe portion (17a) ( 17b) is fixed.
A fastening part (17c) is a fastening band and fastens and fixes the pipe parts (17a) and (17b). A space between the pipe portions (17a) and (17b) is sealed with a gasket (17d).

  As shown in FIG. 6, the exhaust lead-out pipe (2a) of the DPF case (2) is led out from the peripheral wall on one end side of the DPF case (2) to the rear side in the radial direction, and then reversed to the front side. It passes through the side of the SCR support stay (11) that covers one end of (2) and is led out to the front.

  As shown in FIG. 4, of the both ends of the SCR catalyst case (3), the same side as the exhaust outlet pipe (2a) side of the DPF case (2) is one end side, and the opposite side is the other end side. The exhaust introduction pipe (3a) of (3) is led out from the peripheral wall on the other end side while being curved toward one end side.

  The exhaust relay pipe (14) includes a curved pipe part (14b) and a straight pipe part (14a), and the curved pipe part (14b) is a lead-out end part (2) of the exhaust lead-out pipe (2a) of the DPF case (2). 2b), is led out from the outlet end (2b) of the exhaust outlet pipe (2a) while being curved toward the exhaust inlet pipe (3a) of the SCR catalyst case (3), and the straight pipe part (14a) is The straight pipe portion (14a) is led straight out from the lead-out end portion (14c) of the curved pipe portion (14b) toward the exhaust introduction pipe (3a) of the SCR catalyst case (3). It is connected to the exhaust introduction pipe (3a) of the catalyst case (3).

  As shown in FIG. 2, an inlet-side NOx sensor (33) is attached to the lead-out end (2b) of the exhaust lead-out pipe (2a), and as shown in FIG. 4, the curved pipe part of the exhaust relay pipe (14). A urea water injector (16) is attached to (14b), an exhaust temperature sensor (35) is attached to the exhaust introduction pipe (3a) of the SCR catalyst case (3), and an exhaust outlet pipe of the SCR catalyst case (3). A NOx sensor (34) is attached to (3d).

As shown in FIG. 1, an X-shaped reinforcing member (28) is provided, and each upper end of the reinforcing member (28) is fixed to a pair of SCR support stays (11) and (11). The lower end is fixed to the DPF support (10).
Each lower end portion of the reinforcing member (28) is attached to the DPF base bracket (8). That is, each lower end portion of the reinforcing member (28) is fixed to the DPF support (10) via the DPF base bracket (8).

(1) Engine body
(2) DPF case
(2a) Exhaust outlet pipe
(2b) Lead-out end
(3) SCR catalyst case
(3a) Exhaust pipe
(3b) Supported part
(3c) Supported part
(4) DPF
(5) SCR catalyst
(6) Flywheel housing
(7) Cylinder head cover
(10) DPF support
(11) SCR support stay
(12) Cylinder block
(14) Exhaust relay pipe
(14a) Straight pipe
(14b) Curved tube
(14c) Lead-out end
(14d) Lead-out end
(15) Exhaust
(16) Urea water injector
(17) Slip joint
(17a) Pipe section
(17b) Pipe section
(17c) Fastening part
(18) Urea solution
(19) Crankshaft center axis

Claims (6)

An engine body (1), a DPF case (2), and an SCR catalyst case (3);
In the diesel engine in which the DPF case (2) contains the DPF (4) and the SCR catalyst case (3) contains the SCR catalyst (5),
DPF case (2) and SCR catalyst case (3) are mounted on the engine body (1).
A DPF support base (10) and a pair of SCR support stays (11) (11);
The DPF support (10) is provided at the upper part of the flywheel housing (6), and the flywheel housing (6) is a casting disposed at the end of the cylinder block (12). The DPF support (10) The DPF case (2) is mounted on the DPF support (10), and is formed by the built-up portion of the cast flywheel housing (6).
The pair of SCR support stays (11) and (11) is a casting, and each lower part is fixed to a flywheel housing (6) including a DPF support (10), and an SCR catalyst case (3) is supported on each upper part. The parts (3b) and (3c) are placed and fixed,
The SCR catalyst case (3) is oriented along the longitudinal direction of the DPF case (2) ,
The direction in which the crankshaft central axis (19) extends is the front-rear direction, the side with the flywheel housing (6) is the rear side, and the DPF case (2) is directly above the flywheel housing (6), and the cylinder head cover (7 ) Immediately after
A pair of SCR support stays (11), (11) covers the DPF case (2) from both ends thereof, and the SCR catalyst case (3) is supported by the pair of SCR support stays (11), (11). Is a diesel engine, which is arranged directly above the DPF case (2). The diesel engine according to claim 1 ,
An exhaust outlet pipe (2a) of the DPF case (2), an exhaust introduction pipe (3a) of the SCR catalyst case (3), and an exhaust relay pipe (14);
The exhaust relay pipe (14) is interposed between the exhaust outlet pipe (2a) of the DPF case (2) and the exhaust introduction pipe (3a) of the SCR catalyst case (3), and is a straight pipe of the exhaust relay pipe (14). In the section (14a), the exhaust (15) led out from the DPF case (2) and the urea water (18) injected from the urea water injector (16) are mixed,
The diesel engine characterized in that the straight pipe portion (14a) of the exhaust relay pipe (14) is oriented in a direction along the longitudinal direction of the DPF case (2) and the SCR catalyst case (3). The diesel engine according to claim 2 ,
A diesel engine characterized in that the straight pipe portion (14a) of the exhaust relay pipe (14) is disposed right above the cylinder head cover (7) in front of the lower part of the SCR catalyst case (3). In the diesel engine according to claim 2 or 3 ,
Slip joint part (17) (17)
The slip joint portion (17) is disposed at both ends of the exhaust relay pipe (14), and the pipe portions (17a) and (17b) are fitted so as to be extendable and slidable in the axial direction, and are determined by the fastening portion (17c). A diesel engine characterized in that the pipe portions (17a) and (17b) are fixed at the telescopic sliding position . In the diesel engine according to any one of claims 2 to 4 ,
The exhaust lead-out pipe (2a) of the DPF case (2) is led out from the peripheral wall on one end side of the DPF case (2) to the rear side in the radial direction, and then reversed to the front side so that one end side of the DPF case (2) Passing through the side of the covering SCR support stay (11) and led out to the front side,
Of the both ends of the SCR catalyst case (3), the same side as the exhaust outlet pipe (2a) side of the DPF case (2) is one end side, and the opposite side is the other end side.
The exhaust introduction pipe (3a) of the SCR catalyst case (3) is led out from the peripheral wall on the other end side while being curved toward one end side,
The exhaust relay pipe (14) includes a curved pipe part (14b) and a straight pipe part (14a), and the curved pipe part (14b) is a lead-out end part (2) of the exhaust lead-out pipe (2a) of the DPF case (2). 2b), is led out from the outlet end (2b) of the exhaust outlet pipe (2a) while being curved toward the exhaust inlet pipe (3a) of the SCR catalyst case (3), and the straight pipe part (14a) is The straight pipe portion (14a) is led straight out from the lead-out end portion (14c) of the curved pipe portion (14b) toward the exhaust introduction pipe (3a) of the SCR catalyst case (3). A diesel engine characterized in that it is connected to an exhaust introduction pipe (3a) of a catalyst case (3). In the diesel engine according to any one of claims 1 to 5 ,
An X-shaped reinforcing material (28) is provided, each upper end portion of the reinforcing material (28) is fixed to a pair of SCR support stays (11), (11), and each lower end portion of the reinforcing material (28) is a DPF support base ( A diesel engine characterized by being fixed to 10).

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