JP3692276B2 - Engine with fuel injection nozzle - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an engine provided with a fuel injection nozzle.
[0002]
[Prior art]
Conventionally, what is shown in FIG. 6 is known as an engine provided with a fuel injection nozzle. This is because the fuel injection nozzle (113) is accommodated in the head cover (105), the connecting pipe insertion hole (119) is provided in the peripheral side wall (105a) of the head cover (105), and the fuel injection nozzle (113) is provided from the peripheral side surface. The protruding fuel inlet pipe (114) is directed to the connection pipe insertion hole (119), and the connection pipe (120) provided at the outlet end of the fuel supply pipe (112) is passed through the connection pipe insertion hole (119). A tool engaging portion (120a) is provided on the outer portion of the head cover of the connecting pipe (120), and the inner portion of the head cover of the connecting pipe (120) is fitted and screwed into the fuel inlet pipe (114), so that the connecting pipe insertion hole ( 119) is fitted with an annular elastic seal (121).
In this prior art, only the tool engaging portion (120a) is provided on the outer portion of the head cover of the connecting pipe (120).
[0003]
[Problems to be solved by the invention]
The above prior art has the following problems.
<1> The annular elastic seal (121) is easily damaged.
When a tool such as a spanner is engaged with the tool engaging portion (120a) of the connecting pipe (120) and the connecting pipe (120) is screwed onto the fuel inlet pipe (114), the tool is engaged with the tool engaging portion (120a). It slides on the surface of this and hits the annular elastic seal (121), which is easily damaged. If the annular elastic seal (121) is damaged, the connecting tube insertion hole (119) cannot be properly sealed.
[0004]
<< 2 >> Washing water or the like easily enters the head cover (105) from the connecting pipe insertion hole (119).
When cleaning the engine, the cleaning water passing around the tool engaging portion (120a) directly hits the elastic annular seal (121), pushes it open, and enters the head cover (105) from the connecting pipe insertion hole (119). Easy to invade. Moreover, when an engine is mounted on a machine used in a wet paddy such as a rice planting machine, the flying muddy water is likely to enter the head cover (105) from the connection pipe insertion hole (119) for the same reason. The entry of these foreign substances into the head cover (105) contaminates the lubricating oil and shortens its useful life.
[0005]
The subject of this invention is providing the engine provided with the fuel-injection nozzle which can solve the said problem.
[0006]
[Means for Solving the Problems]
(Invention of Claim 1)
The configuration of the invention of claim 1 is as follows.
As shown in FIG. 2, the fuel injection nozzle (13) is accommodated in the head cover (5), the connecting pipe insertion hole (19) is provided in the peripheral side wall (5a) of the head cover (5), and the fuel injection nozzle (13). The fuel inlet pipe (14) protruding from the peripheral side of the fuel pipe is directed to the connecting pipe insertion hole (19), and the connecting pipe (20) provided at the outlet end of the fuel supply pipe (12) is connected to the connecting pipe insertion hole (19). A tool engaging portion (20a) is provided in the outer portion of the head cover of the connecting pipe (20), and the inner portion of the head cover of the connecting pipe (20) is fitted and screwed into the fuel inlet pipe (14) for connection. In an engine having a fuel injection nozzle in which an annular elastic seal (21) is fitted in a pipe insertion hole (19),
At a position closer to the annular elastic seal (21) than the tool engaging portion (20a), a tool receiving flange (20b) larger in diameter than the tool engaging portion (20a) is provided on the outer portion of the head cover of the connecting pipe (20). )
As shown in FIG. 1, the fulcrum portion (51), the force point portion (53), lever with the force output portion (52) (46) and the pressing bolt (47) and nozzle retainer having a (48) is provided, by pressing force point portion (53) of the lever (46) with a pressing portion (54) of the holding bolts (47), the action point portion of the lever (46) which swings about a fulcrum portion (51) (52) Then, the fuel injection nozzle (13) is pushed into the nozzle insertion hole (33) of the cylinder head (3), the pushing force (46a) fixes the fuel injection nozzle (13) to the cylinder head (3), and the stopper ( 49 ) An engine provided with a fuel injection nozzle, characterized by receiving an insulator ( 46 ) swinging around a fulcrum ( 51 ) and making the pushing force (46a) of the fuel injection nozzle (13) difficult to become excessive. .
[0007]
(Invention of Claim 2)
The configuration of the invention of claim 2 is as follows.
In the engine provided with the fuel injection nozzle according to claim 1, as shown in FIG. 2, an O-ring (22) is provided between the fitting surfaces of the connection pipe (20) and the fuel inlet pipe (14). An engine equipped with a fuel injection nozzle.
[0008]
(Invention of Claim 3)
The configuration of the invention of claim 3 is as follows.
In the engine provided with the fuel nozzle according to claim 1 or 2,
As shown in FIG. 2, the inner end portion (21 a) of the annular seal (21) is retreated in the projecting direction of the fuel inlet pipe (14) from the projecting end section (14 a) of the fuel inlet pipe (14). An engine equipped with a fuel injection nozzle.
[0010]
(Invention of Claim 4 )
The configuration of the invention of claim 4 is as follows.
In the engine provided with the fuel injection nozzle according to any one of claims 1 to 3 , as shown in FIG. 3 (A), a fuel injection nozzle (13) is formed at an action point portion (52) of the insulator (46). Engine equipped with a fuel injection nozzle characterized by
[0011]
[Action and effect of the invention]
(Invention of Claim 1)
The invention of claim 1 has the following effects.
<< 1 >> The annular elastic seal (21) is hardly damaged.
As apparent from FIG. 2, when a tool such as a spanner is engaged with the tool engaging portion (20a) of the connecting pipe (20) and the connecting pipe (20) is screwed to the fuel inlet pipe (14), the tool Even if the tool slides on the surface of the tool engaging portion (20a), the tool is received by the tool receiving flange (20b) and does not hit the annular elastic seal (21). For this reason, the annular elastic seal (21) is hardly damaged, and the connecting pipe insertion hole (19) can be properly sealed.
[0012]
<< 2 >> Washing water or the like hardly enters the head cover (5) from the connecting pipe insertion hole (19).
As is apparent from FIG. 2, when the engine is cleaned, the cleaning water passing around the tool engaging portion (20a) is received by the tool receiving flange (20b), and hardly hits the elastic annular seal (21). Therefore, it is difficult for cleaning water to enter the head cover (5) from the connecting pipe insertion hole (19). In addition, when an engine is mounted on a machine used in a wet paddy such as a rice planting machine, the flying muddy water is unlikely to enter the head cover (5) from the connection pipe insertion hole (19) for the same reason. In this way, by suppressing the intrusion of these foreign substances into the head cover (5), the lubricating oil is hardly contaminated and its useful life is extended.
<< 3 >> The direction of the fuel inlet pipe ( 14 ) with respect to the connecting pipe insertion hole ( 19 ) can be set appropriately.
As shown in FIG. 1, a fuel injection nozzle (13) for securing is pushed into the nozzle insertion hole of the cylinder head (3) (33), a fuel injection nozzle (13) is screwed into the nozzle insertion hole (33) Compared to the case of fixing, the direction of the fuel inlet pipe ( 14 ) with respect to the connecting pipe insertion hole ( 19 ) can be set appropriately. For this reason, the connecting pipe ( 20 ) has an appropriate posture in the connecting pipe insertion hole ( 19 ) , and an appropriate sealing force of the annular elastic seal ( 21 ) can be ensured.
<< 4 >> The position and orientation of the fuel inlet pipe ( 14 ) with respect to the connecting pipe insertion hole ( 19 ) can be set appropriately.
As is clear from FIG. 3 ( C ) , the tightening torque of the holding bolt ( 47 ) is insufficiently controlled, and the lever ( 46 ) is received by the stopper ( 49 ) even if the tightening torque is too strong. The pushing force ( 46a ) shown in FIG. 1 is unlikely to be excessive, the fuel injection nozzle ( 13 ) is not easily deformed or excessively pushed, and the position and orientation of the fuel inlet pipe ( 14 ) with respect to the connecting pipe insertion hole ( 19 ) . Can be set appropriately. For this reason, the connecting pipe ( 20 ) takes an appropriate position and posture in the connecting pipe insertion hole ( 19 ) , and an appropriate sealing force of the annular elastic seal ( 21 ) can be secured.
[0013]
(Invention of Claim 2)
The invention of claim 2 has the following effects in addition to the effects of the invention of claim 1.
<< 5 >> It is difficult for the fuel to enter the head cover (5) from the fitting portion between the connecting pipe (20) and the fuel inlet pipe (14).
As is apparent from FIG. 2, the fuel traveling from the fitting portion between the connecting pipe (20) and the fuel inlet pipe (14) into the head cover (5) is received by the O-ring (22), It is hard to invade. Thus, by suppressing the intrusion of the fuel into the head cover (5), the lubricating oil is hardly contaminated and its useful life is extended.
[0014]
(Invention of Claim 3)
The invention of claim 3 has the following effects in addition to the effects of the invention of claim 1 or claim 2.
<6> The head cover (5) can be easily attached and detached.
As is apparent from FIG. 2, the head cover (5) is attached to the cylinder head (3) with the fuel supply pipe (12) and its connecting pipe (20) not inserted into the annular elastic seal (21). When attaching and detaching, even if the annular elastic seal (21) is fitted in the connecting pipe insertion hole (19), the inner end portion (21a) of the annular elastic seal (21) is the protruding end portion of the fuel inlet pipe (14) ( 14a) is not caught. For this reason, when attaching / detaching the head cover (5), it is not necessary to insert and remove the annular elastic seal (21), and the head cover (5) can be attached / detached easily.
[0017]
(Invention of Claim 4 )
The invention of claim 4 has the following effects in addition to the effects of any one of claims 1 to 3 .
<< 7 >> The proper orientation of the fuel inlet pipe (14) with respect to the connecting pipe insertion hole (19) can be maintained.
As shown in FIG. 3 (A), since the fuel injection nozzle (13) is prevented from rotating, as is clear from FIG. 2, the proper orientation of the fuel inlet pipe (14) with respect to the connecting pipe insertion hole (19) is set. Can be maintained. For this reason, the connecting pipe (20) is maintained in an appropriate posture within the connecting pipe insertion hole (19), and an appropriate sealing force of the annular elastic seal (21) is maintained.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings. 1 to 5 are views for explaining a multi-cylinder vertical diesel engine according to an embodiment of the present invention. The configuration of the diesel engine (1) is as follows.
[0019]
As shown in FIG. 1, the cylinder head (3) is assembled to the upper part of the cylinder block (2), and the head cover (5) is assembled to the upper part of the cylinder head (3). A piston (31) is fitted in the cylinder (30) of the cylinder block (2), and a cavity (32) is formed in the piston (31). The diesel engine (1) includes a valve gear (4) and a fuel supply device.
[0020]
The configuration of the valve gear (4) is as follows.
As shown in FIG. 1, the valve operating device (4) is connected in order from a valve operating cam (36) to a tappet (43), a push rod (41), a rocker arm (40), and a valve bridge (42) shown in FIG. Then, the intake valve (26) and the exhaust valve (27) are opened and closed. 1 and 4, the reference numeral (40a) is an input end of the rocker arm (40), and (40b) is an output end. As shown in FIG. 4, the rocker arm (40) is pivotally supported by a rocker arm pivot (39) supported by a rocker arm bracket (37). As shown in FIG. 1, the rocker arm bracket (37) is fixed to the upper surface of the cylinder head (3) with a fixing bolt (38). The rocker arm bracket (37) and the rocker arm (40) are accommodated in the head cover (5).
[0021]
The configuration of the fuel supply device is as follows.
As shown in FIG. 1, the fuel supply device includes a fuel supply pipe (12) led out from a fuel supply pump (not shown) and a fuel injection nozzle (13). The fuel supply pipe (12) is provided with a connection pipe (20) at its outlet end. The fuel injection nozzle (13) is attached to the nozzle insertion hole (33) of the cylinder head (3) in a direction along the cylinder central axis (44). The fuel injection nozzle (13) includes a fuel inlet pipe (14), a nozzle portion (13a), and an overflow fuel outlet pipe (15). The fuel inlet pipe (14) protrudes laterally from the peripheral side surface of the fuel injection nozzle (13). The nozzle portion (13a) is provided at the lower end of the fuel injection nozzle (13) and faces the cavity (32) of the piston (31). The overflow fuel outlet pipe (15) is provided at the upper end of the fuel injection nozzle (13). The fuel injection nozzle (13) is accommodated in the head cover (5).
[0022]
An outlet insertion pipe (15a) is formed on the ceiling wall of the head cover (5), and an overflow fuel outlet pipe (15) is inserted vertically there. A gap between the outlet pipe insertion hole (15a) and the overflow fuel outlet pipe (15) is sealed with an annular elastic seal (15b) fitted in the outlet pipe insertion hole (15a). A connection pipe insertion hole (19) is provided in the peripheral side wall (5a) of the head cover (5), and the fuel inlet pipe (14) of the fuel injection nozzle (13) is directed to the connection pipe insertion hole (19). . On the other hand, the connecting pipe (20) of the fuel supply pipe (12) passes through the connecting pipe insertion hole (19). As shown in FIG. 2, a hexagonal nut-shaped tool engaging portion (20a) is provided in the outer portion of the head cover of the connecting pipe (20). A portion of the connecting pipe (20) in the head cover is externally fitted and screwed to the fuel inlet pipe (14) of the fuel injection nozzle (13). By this screwing, the fuel outlet of the fuel supply pipe (12) and the fuel inlet of the fuel inlet pipe (14) are connected in abutting manner. An O-ring (22) is provided between the fitting surfaces of the connecting pipe (20) and the fuel inlet pipe (14). The O-ring (22) is fitted in a groove (23) formed in the fuel inlet pipe (14).
[0023]
An annular elastic seal (21) is fitted in the connecting pipe insertion hole (19). The annular elastic seal (21) includes an insertion hole side pressure contact portion (21b) that is pressed against the inner peripheral surface of the connection tube insertion hole (19), and a connection tube side pressure contact portion that is pressed against the outer peripheral surface of the connection tube (20). (21c), an elastic part (21d) interposed therebetween, and a shape-retaining material (21e) for retaining the insertion hole-side pressure contact part (21b). The inner end portion (21a) of the annular elastic seal (21) retreats in the projecting direction of the fuel inlet pipe (14) from the projecting end portion (14a) of the fuel inlet pipe (14) of the fuel injection nozzle (13). ing. The gap between the connecting pipe insertion hole (19) and the connecting pipe (20) is sealed with this annular elastic seal (21). A tool receiving flange (20b) having a diameter larger than that of the tool engaging portion (20a) is provided on the outer portion of the head cover of the connecting pipe (20) at a position closer to the annular elastic seal (21) than the tool engaging portion (20a). It has been. The tool receiving flange (20b) is formed larger in diameter than the elastic part (21d) and the connecting pipe side pressure contact part (21c) of the annular elastic seal (21) so that they are not damaged when hitting the tool. At the same time, they are prevented from being pushed open by washing water or the like.
[0024]
The fixing structure of the fuel injection nozzle (13) is as follows.
As shown in FIG. 1, the rocker arm bracket (37) is provided with a nozzle pressing member (48). The nozzle pressing tool (48) includes a lever (46) and a pressing bolt (47). As shown in FIG. 3 (A), the insulator (46) is formed in a flat plate shape, a non-rotating hole (60) is formed at the distal end thereof, a bolt insertion hole (59) is formed at the central portion, and the proximal end A pin engaging hole (64) is formed in the portion. As shown in FIG. 1, the holding bolt (47) includes a nut serving as a pressing portion (54) at its upper end. A base end portion of the lever (46) is placed on the rocker arm bracket (37), and a knock pin (63) driven into the rocker arm bracket (37) is fitted into the pin fitting portion (64). As shown in FIG. 3A, the flat shaft portion (28) of the fuel injection nozzle (13) is fitted into the rotation stop hole (60) at the tip of the insulator (46). As shown in FIG. 3 (B), the tip of the insulator (46) is placed on the pressure receiving surface (58) of the fuel injection nozzle (13) at the lower part on both sides of the flat shaft portion (28) of the fuel injection nozzle (13). Have a close relationship.
[0025]
As shown in FIG. 1, the holding bolt (47) is erected on the cylinder head (3), and its upper end is inserted into the bolt insertion hole (59) of the insulator (46) to form the pressing portion (47). The central portion of the insulator (46) is pressed from above with a nut. For this reason, the base end portion of the insulator (46) is a fulcrum portion (51), the central portion is a force point portion (53), and the tip portion is an action point portion (52), and the fuel injection nozzle ( The pressure receiving surface (58) of 13) is pressed, the fuel injection nozzle (13) is pushed into the nozzle insertion hole (33), and is fixed to the cylinder head (3). A copper packing (61) is provided at the back end of the nozzle insertion hole (33), and the fuel injection nozzle (13) is pressed against this. As shown in FIGS. 3A and 3C, the rocker arm bracket (37) is provided with a stopper (49). The stopper (49) is disposed on both sides of the holding bolt (47) and receives the force point portion (53) of the lever (46). For this reason, the insulator (46) is not easily distorted, and the pushing force (46a) of the fuel injection nozzle (13) shown in FIG. 1 is unlikely to deviate from an appropriate value.
[0026]
As shown in FIG. 3D, a bolt fitting groove seat (50) is formed in the rocker arm bracket (37), and a holding bolt (47) is fitted therein. For this reason, the rocker arm bracket (37) is prevented from rotating by the holding bolt (47). Further, as shown in FIG. 1, the pressing force by the fixing bolt (38) for fixing the rocker arm bracket (37) to the cylinder head (3) and the pressing force by the fulcrum part (51) of the lever (46) are the rocker arm. It acts on mutually opposite portions (67) and (68) of the rocker arm bracket (37) with the pivot (39) interposed therebetween. For this reason, when the rocker arm (40) is actuated, lifting of the mutually opposite portions (67) and (68) of the rocker arm bracket (37) is suppressed, and the deviation of the intake and exhaust timing due to this is suppressed. In addition, the code | symbol (69) in FIG. 1 is a lubricating oil supply path to the rocker arm (40).
[0027]
As shown in FIG. 1, a plug insertion hole (34) is formed in the cylinder head (3), and a glow plug (35) is inserted into the cylinder head (3). The tip of the plug (35) is the cavity (32) of the piston (31). ) As shown in FIG. 5, when viewed in a direction parallel to the cylinder center axis (44), the fuel injection axes (70) and (70) adjacent to the fuel injection nozzle (13) are located on both sides of the glow plug (35). pass. For this reason, the direct injection of the injected fuel to the glow plug (35) hardly occurs, and it is possible to suppress the burning of the glow plug (35) due to this.
[Brief description of the drawings]
FIG. 1 is an upper longitudinal front view of an engine according to an embodiment of the present invention.
FIG. 2 is a longitudinal sectional front view of a main part of the engine of FIG.
3A is a cross-sectional view taken along line AA in FIG. 1, FIG. 3B is a cross-sectional view taken along line BB in FIG. 1, and FIG. 3C is a cross-sectional view taken along line CC in FIG. FIG. 3D is a cross-sectional view taken along the line DD of FIG.
4 is a plan view with the head cover of the engine of FIG. 1 removed. FIG.
5 is a schematic diagram for explaining the orientation of a glow plug and a fuel injection axis of the engine of FIG. 1. FIG.
FIG. 6 is a view corresponding to FIG. 2 of the prior art.
[Explanation of symbols]
(3) ... Cylinder head, (5) ... Head cover, (5a) ... Peripheral side wall, (12) ... Fuel supply pipe, (13) ... Fuel injection nozzle, (14) ... Fuel inlet pipe, (14a) ... Projection end Part, (19) ... connection pipe insertion hole, (20) ... connection pipe, (20a) ... tool engaging part, (20b) ... tool receiving flange, (21) ... annular elastic seal, (21a) ... inner end part , (22) ... O-ring, (33) ... Nozzle insertion hole, (46) ... insulator, (46a) ... Pushing force, (47) ... Presser bolt, (48) ... Nozzle presser, (49) ... Stopper, (52) ... action point part, (53) ... force point part, (54) ... pressing part.

Claims (4)

A fuel injection nozzle (13) is accommodated in the head cover (5), a connecting pipe insertion hole (19) is provided in the peripheral side wall (5a) of the head cover (5), and the fuel protrudes from the peripheral side surface of the fuel injection nozzle (13). The inlet pipe (14) faces the connection pipe insertion hole (19), and the connection pipe (20) provided at the outlet end of the fuel supply pipe (12) is passed through the connection pipe insertion hole (19). 20) A tool engaging portion (20a) is provided on the outer portion of the head cover, and the inner portion of the head cover of the connecting pipe (20) is fitted into the fuel inlet pipe (14) and screwed into the connecting pipe insertion hole (19). In an engine having a fuel injection nozzle fitted with an annular elastic seal (21),
At a position closer to the annular elastic seal (21) than the tool engaging portion (20a), a tool receiving flange (20b) larger in diameter than the tool engaging portion (20a) is provided on the outer portion of the head cover of the connecting pipe (20). )
Fulcrum (51), the force point portion (53), a nozzle retainer (48) is provided with a lever with the force output portion (52) (46) and the pressing bolt (47), pressing of the pressing bolt (47) parts by pressing the lever (46) point portion (53) in (54), the action point portion of the lever (46) which swings about a fulcrum portion (51) (52) fuel injection nozzle (13) Is pushed into the nozzle insertion hole (33) of the cylinder head (3), the fuel injection nozzle (13) is fixed to the cylinder head (3) by the pushing force (46a ) , and the fulcrum portion ( 51 ) is fixed by the stopper ( 49 ). An engine provided with a fuel injection nozzle, characterized by receiving an insulator ( 46 ) that swings as a center and making it difficult for the pushing force (46a) of the fuel injection nozzle (13) to become excessive. 2. An engine comprising a fuel injection nozzle according to claim 1, wherein an O-ring (22) is provided between the fitting surfaces of the connection pipe (20) and the fuel inlet pipe (14). An engine with an injection nozzle. In the engine provided with the fuel nozzle according to claim 1 or 2,
The inner end (21a) of the annular elastic seal (21) is retracted in the protruding direction of the fuel inlet pipe (14) from the protruding end (14a) of the fuel inlet pipe (14). An engine with a fuel injection nozzle. In the engine provided with the fuel injection nozzle according to any one of claims 1 to 3 , the fuel injection nozzle (13) is prevented from rotating at an action point portion (52) of the insulator (46). An engine equipped with a fuel injection nozzle.

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