JP4157691B2 - Diesel engine swirl chamber combustion chamber - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a vortex chamber combustion chamber of a diesel engine.
[0002]
[Prerequisite configuration]
  The vortex chamber combustion chamber of the diesel engine according to the present invention is intended for the one having the following premise configuration as shown in FIGS. 1 and 2 (present invention) or FIG. 7 (prior art), for example.
[0003]
  1 and 2 show Embodiment 1 of a vortex chamber type combustion chamber of a diesel engine of the present invention. FIG. 2 is a vertical right side view of a vortex chamber combustion chamber of a diesel engine. 1A is a vertical right side view of the nozzle mouthpiece, and FIG. 1B is a plan view of FIG. FIG. 1C is an enlarged view of a main part of the nozzle hole in FIG. 1D is a plan view of FIG. 1C, FIG. 1E is a bottom view of FIG. 1C, and FIG. 1F is a view taken in the direction of arrow F in FIG. FIG. 1G is a perspective view of the nozzle hole of FIG. 1C viewed from obliquely above, and FIG. 1H is a perspective view of the nozzle hole of FIG. 1C viewed obliquely from below.
[0004]
  FIG. 7 shows the shape of the nozzle hole according to the prior art. FIG. 7A is a vertical right side view of the nozzle hole. 7B is a plan view of FIG. 7A, FIG. 7C is a bottom view of FIG. 7A, and FIG. 7D is a view as viewed from the direction of arrow D in FIG. 7A. FIG. 7E is a perspective view of the nozzle hole of FIG. 7A viewed from obliquely above, and FIG. 7F is a perspective view of the nozzle hole of FIG. 7A viewed obliquely from below.
[0005]
  The vortex chamber (2) is communicated with the main chamber (1) of the vortex chamber type combustion chamber of the diesel engine through the nozzle (3). The compressed air flow (6) that has been press-fitted into the vortex chamber (2) from the main chamber (1) through the nozzle (3) in the compression process turns into an air vortex (7) in the vortex chamber (2). To be configured. The fuel injection nozzle (8) faces the vortex chamber (2).
  The shape of the nozzle hole (3) is formed by connecting the lateral sides of the pair of left and right side nozzle holes (22), (22) to the left and right sides of the main nozzle hole (21). The axial centers (23) and (23) of the side nozzle holes (22) and (22) are inclined to each other at a converging point and intersect at an intersection (24). This intersection (24) is located closer to the vortex chamber peripheral surface (12) of the vortex chamber (2) than the axis (25) of the main nozzle hole (21).
[0006]
[Prior art]
  In the above premise configuration, there is a conventional shape shown in FIG. 7 as a specific shape of the nozzle hole (3).
  FIG. 7 shows the shape of the nozzle hole according to the prior art. FIG. 7A is a vertical right side view of the nozzle hole. 7B is a plan view of FIG. 7A, FIG. 7C is a bottom view of FIG. 7A, and FIG. 7D is a view as viewed from the direction of arrow D in FIG. 7A. FIG. 7E is a perspective view of the nozzle hole of FIG. 7A viewed from obliquely above, and FIG. 7F is a perspective view of the nozzle hole of FIG. 7A viewed obliquely from below.
[0007]
  The main injection hole (21) and the side injection holes (22) and (22) constituting the injection hole (3) are simply formed in a cylindrical shape, and open to the peripheral surface (12) of the vortex flow chamber (2). Just doing.
  Along each of the front and left and right boundary portions of the front and left and right boundary holes formed by the main nozzle hole (21) and the left and right side nozzle holes (22) and (22), respectively, A micro eddy current generating groove (32) (32) is formed, and the end of the micro eddy current generating groove (32) (32) is opened to the peripheral surface (12) of the vortex chamber (2). is there.
[0008]
[Problems to be solved by the invention]
  The above prior art has the following problems.
  [ I. Since the compressed air flow (6) flows straight into the vortex chamber (2) from the nozzle (3), the air vortex (7) spreads widely from the central space portion in the vortex chamber (2) to the left and right side space portions. As much as it is difficult to reach, the mixing performance of air and fuel in the vortex chamber (2) is difficult to improve, and the air utilization rate is difficult to improve. ]
[0009]
  FIG. 4 (A) is a diagram schematically showing the function of a conventional nozzle, and FIG. 4 (B) is a cross-sectional view taken along the line BB of FIG. 4 (A). As shown in FIGS. 4 (A) and 4 (B), the compressed air flow (6) pressed into the vortex chamber (2) from the main chamber (1) through the nozzle (2) in the compression step is At the stage of passing through 3), it goes straight through the nozzle (3) and flows straight into the vortex chamber (2).
[0010]
  Therefore, the air vortex flow (7) is mixed with air and fuel in the vortex flow chamber (2) by the amount that is difficult to spread from the central space portion to the left and right side space portions in the vortex flow chamber (2). It is difficult to increase the air utilization rate.
  Thereby, PM (particulate material = particulate matter) cannot be reduced without deteriorating NOx (nitrogen oxide) in the combustion exhaust gas.
[0011]
  [B. Since the air vortex (7) is difficult to reach because it spreads widely to the left and right sides of the vortex chamber (2), the micro vortex (46) in FIG. Increases the contact rate and contact speed between air and fuel, and the ignition delay time from the start of fuel injection to the start of ignition cannot be shortened, and the amount of NOx (nitrogen oxide) generated in the combustion exhaust gas is reduced I can't. ]
[0012]
  Since the compressed air flow (6) flows straight into the vortex chamber (2) from the nozzle (3), the air vortex (7) spreads widely from the central space portion in the vortex chamber (2) to the left and right side space portions. It is hard to go. Thereby, the micro eddy current (46) generated by the groove passing air flow (45) that has passed through the micro eddy current generating groove (32) of FIG. 3 (C) is widely diffused in the lateral width direction of the air vortex (7). It is hard to go. For this reason, the micro eddy current (46) increases the contact rate / contact speed between the air and the fuel, so that the ignition delay time from the start of fuel injection to the start of ignition cannot be shortened. ) Cannot be reduced.
[0013]
  An object of the present invention is to do as follows.
  (I). In the vortex chamber, the air vortex is broadly expanded from the central space portion to the left and right side space portions in the vortex chamber, so that the mixing performance of air and fuel is improved and the air utilization rate is improved. (Particulate material = particulate matter) is reduced.
[0014]
  (B). In the vortex chamber, the air vortex is broadly expanded from the central space portion to the left and right side space portions in the vortex chamber, so that the micro vortex flow (46) generated by the groove passing air flow (45) in FIG. ) Is widely diffused in the lateral direction of the air vortex, and the micro vortex increases the contact rate and contact speed between the air and the fuel to shorten the ignition delay time from the start of fuel injection to the start of ignition. Reduce the amount of NOx (nitrogen oxide) generated in the exhaust gas.
[0015]
[Means for Solving the Problems]
  The vortex chamber combustion chamber of the diesel engine according to the present invention has the following feature configuration as shown in FIG. 1 to FIG. 5 or FIG. Features.
[0016]
  FIG. 1 to FIG. 5 (A) show Embodiment 1 of the vortex chamber type combustion chamber of the diesel engine of the present invention. 1A is a vertical right side view of the nozzle mouthpiece, and FIG. 1B is a plan view of FIG. FIG. 1C is an enlarged view of a main part of the nozzle hole in FIG. 1D is a plan view of FIG. 1C, FIG. 1E is a bottom view of FIG. 1C, and FIG. 1F is a view taken in the direction of arrow F in FIG. FIG. 1G is a perspective view of the nozzle hole of FIG. 1C viewed from obliquely above, and FIG. 1H is a perspective view of the nozzle hole of FIG. 1C viewed obliquely from below.
[0017]
  FIG. 2 is a vertical right side view of a vortex chamber combustion chamber of a diesel engine. 3A is a longitudinal front view schematically showing the function of the main nozzle hole and the side nozzle hole of the nozzle hole, and FIG. 3B is a vertical right side view of FIG. 3A. FIG. 3C is a front view of a longitudinal section of a main part schematically showing the function of the micro eddy current generating groove. FIG. 4 is a diagram schematically showing the function of the nozzle hole. 4A is a vertical right side view of a conventional nozzle and vortex chamber, and FIG. 4B is a cross-sectional view taken along line BB in FIG. 4A. 4C is a longitudinal right side view of the nozzle and vortex chamber of the present invention, and FIG. 4D is a cross-sectional view taken along line DD of FIG. 4C.
[0018]
  FIG. 5 is a vertical right side view of the smooth connection surface of the nozzle hole showing the first, second, and third embodiments of the present invention. 5A shows the first embodiment, FIG. 5B shows the second embodiment, and FIG. 5C shows the third embodiment.
[0019]
  FIG. 6 shows the shape of a nozzle hole according to Embodiment 4 of the present invention. FIG. 6A is a vertical right side view of the nozzle hole. 6 (B) is a plan view of FIG. 6 (A), FIG. 6 (C) is a bottom view of FIG. 6 (A), and FIG. 6 (D) is a view taken in the direction of arrow D in FIG. 6E is a perspective view of the nozzle hole of FIG. 6A viewed from obliquely above, and FIG. 6F is a perspective view of the nozzle hole of FIG. 6A viewed from diagonally below.
[0020]
    ○ Invention 1. Claim 1.1-5reference.
  The present invention 1 is characterized in that the following feature configuration is added to the premise configuration.
  Of the main nozzle hole peripheral edge (9) where the main nozzle hole (21) is connected to the vortex chamber (2), the main nozzle hole (21) is seen from the center (5) of the vortex chamber (2). In the outer peripheral side peripheral portion (10) located outside the axis (25), the outer peripheral portion (11) closer to the outer periphery of the main nozzle hole (21) and the vortex chamber peripheral surface (12) of the vortex chamber (2) The main nozzle hole smooth connection surface (13) for smoothly connecting the two is formed.
[0021]
  In the inner peripheral side peripheral portion (14) located on the opposite side of the outer peripheral side peripheral portion (10) of the main injection hole end peripheral portion (9), the inner peripheral peripheral surface portion ( 15) and the vortex chamber peripheral surface (12) of the vortex chamber (2) can be directly connected with an acute angle.
  Along the front and right and left and right boundary portions of the front and right and left and right side nozzle holes (22) and (22), respectively, at least two front and left boundary portions, The micro eddy current generating grooves (32) and (32) are formed respectively. The groove end portions of the micro eddy current generating grooves (32) and (32) are formed by opening the peripheral surface (12) of the vortex chamber (2).,
  Each side nozzle hole (twenty two) Vortex chamber ( 2 ) The peripheral edge of the end of the side nozzle hole (26) The side nozzle hole (twenty two) Peripheral part of (28) And vortex chamber ( 2 ) Eddy current chamber (12) Side nozzle holes for smooth connection (29) Is formed.
[0022]
    ○ Invention 2. Claim 2. See FIGS. 1 and 5B.
  This invention 2Prerequisite configurationThe following feature configuration is added.
  Main nozzle hole (twenty one) Vortex chamber ( 2 ) The peripheral edge of the main nozzle hole ( 9 ) Of the vortex chamber ( 2 ) Heart of ( 5 ) Main nozzle hole seen from (twenty one) Axis of (twenty five) Outer periphery side peripheral part located outside (Ten) At the main nozzle hole (twenty one) The outer surface of the outer surface (11) And vortex chamber ( 2 ) Eddy current chamber (12) Smooth connection surface for main nozzle holes (13) Form the
Main nozzle hole peripheral edge ( 9 ) Of the outer periphery side peripheral portion (Ten) Inner periphery side peripheral edge located on the opposite side (14) At the main nozzle hole (twenty one) The inner surface of the peripheral surface (15) And vortex chamber ( 2 ) Eddy current chamber (12) Can be directly connected to form an acute angle,
Main nozzle hole (twenty one) And left and right side nozzle holes (22) (22) Grooves for generating micro eddy currents along at least the two front and right boundary parts of the total of four front and rear boundary parts (32) (32) This micro eddy current generating groove is formed (32) (32) The vortex chamber at the end of the groove ( 2 ) Eddy current chamber (12) Open to
  The vertical cross-sectional shape of the main nozzle hole smooth connection surface (13) gradually approaches from the outer peripheral surface portion (11) of the main nozzle hole (21) to the vortex chamber peripheral surface (12) of the vortex chamber (2). It consists of a multi-step bent continuous inclined surface (16).
[0023]
    ○ Invention 3. Claim 3. See FIGS. 1 and 5C.
  This invention 3Prerequisite configurationThe following feature configuration is added.
  Main nozzle hole (twenty one) Vortex chamber ( 2 ) The peripheral edge of the main nozzle hole ( 9 ) Of the vortex chamber ( 2 ) Heart of ( 5 ) Main nozzle hole seen from (twenty one) Axis of (twenty five) Outer periphery side peripheral part located outside (Ten) At the main nozzle hole (twenty one) The outer surface of the outer surface (11) And vortex chamber ( 2 ) Eddy current chamber (12) Smooth connection surface for main nozzle holes (13) Form the
Main nozzle hole peripheral edge ( 9 ) Of the outer periphery side peripheral portion (Ten) Inner periphery side peripheral edge located on the opposite side (14) At the main nozzle hole (twenty one) The inner surface of the peripheral surface (15) And vortex chamber ( 2 ) Eddy current chamber (12) Can be directly connected to form an acute angle,
Main nozzle hole (twenty one) And left and right side nozzle holes (22) (22) Grooves for generating micro eddy currents along at least the two front and right boundary parts of the total of four front and rear boundary parts (32) (32) This micro eddy current generating groove is formed (32) (32) The vortex chamber at the end of the groove ( 2 ) Eddy current chamber (12) Open to
  The vertical cross-sectional shape of the main nozzle hole smooth connection surface (13) gradually approaches from the outer peripheral surface portion (11) of the main nozzle hole (21) to the vortex chamber peripheral surface (12) of the vortex chamber (2). Consists of gently convex curved surface (17).
[0024]
    ○ Invention 4. Claim 4. See FIG.
  This invention 4 is the above invention.2 or 3The following feature configuration is added.
  In the peripheral edge portion (26) of the side nozzle hole where the side nozzle holes (22) are connected to the vortex chamber (2), the peripheral surface portion (28) of the side nozzle hole (22) and the vortex flow in the vortex chamber (2) A side injection hole smooth connection surface (29) for smoothly connecting the chamber peripheral surface (12) was formed.
[0025]
    ○ Invention 5. Claim 5. See FIGS. 1 and 5B.
  This invention 5 is the above invention.1 or4 is characterized in that the following feature configuration is added.
  The vertical cross-sectional shape of the side nozzle hole smooth connection surface (29) gradually approaches the peripheral surface portion (28) of the side nozzle hole (22) from the peripheral surface (12) of the vortex chamber (2). It consists of a multi-step bent continuous inclined surface (30).
[0026]
    ○ Invention 6. Claim 6. See FIGS. 1 and 5C.
  This invention 6 is the above invention.1 or4 is characterized in that the following feature configuration is added.
  The vertical cross-sectional shape of the side nozzle hole smooth connection surface (29) gradually approaches the peripheral surface portion (28) of the side nozzle hole (22) from the peripheral surface (12) of the vortex chamber (2). It consists of a gentle convex surface (31).
[0027]
【The invention's effect】
  The vortex chamber combustion chamber of the diesel engine of the present invention has the following effects.
    ○ Invention 1. Claim 1.1-5reference.
  [ I.1.The main air vortex (43) and the pair of left and right side air vortices (44) (44) spread over a wide range from the central space portion of the vortex chamber (2) to the left and right side space portions;2.The negative pressure of the main nozzle hole smooth connection surface (13) attracts the lateral width of the main air vortex (43), and3.Accelerating the collision and reflection of the pair of left and right side compressed air flows (42) and (42) by the negative pressure pulling action of the main compressed air flow (41) on the main nozzle hole smooth connection surface (13) As a result of the synergistic effect of the person, the mixing performance and air utilization rate of air and fuel in the vortex chamber (2) are greatly improved, and PM is reduced without deteriorating NOx in the combustion exhaust gas.
  ]
[0028]
  "Action1. The main air vortex flow (43) and the pair of left and right side air vortex flows (44) and (44) spread over a wide range from the central space portion of the vortex flow chamber (2) to the left and right side space portions. Utilization rate is improved. "
[0029]
  As shown in FIGS. 3A and 3B, in the compression stroke, the main compressed air passes from the main chamber (1) through the main nozzle hole (21) and the pair of left and right side nozzle holes (22) and (22). The flow (41) and the compressed air flows (42) (42) on both sides are pressed into the vortex chamber (2) in parallel.
[0030]
  First, the main compressed air flow (41) that has passed through the main nozzle hole (21) swirls in the vortex chamber (2) to become the main air vortex flow (43), mainly in the center in the vortex chamber (2). Spread left and right near the space.
  Next, the left and right side compressed air streams (42) and (42) that have passed through the pair of left and right side nozzle holes (22) and (22) enter the vortex chamber (2) and proceed a little, and then the main compressed air stream (41) Collide with each other at the intersection (24) farther below (24), reflect, and spread left and right. For this reason, the air vortices (44) (44) on both sides mainly separate from the central space portion in the vortex chamber (2) and spread to the left and right side space portions.
[0031]
  As a result, the main air vortex (43) and the pair of left and right side air vortices (44) (44) spread widely from the central space portion of the vortex chamber (2) to both side space portions. For this reason, the mixing performance of air and fuel in the vortex chamber (2) is improved, and the air utilization rate is improved.
[0032]
  "Action2. The lateral width of the main air vortex (43) is expanded by the negative pressure pulling action of the main nozzle hole smooth connection surface (13). "
[0033]
  As shown in FIGS. 4 (C) and 4 (D), the main compressed air flow (41) that is press-fitted into the vortex chamber (2) from the main chamber (1) through the main nozzle hole (21) in the compression step is: In the stage of passing through the main nozzle hole (21), after being guided by the main nozzle hole (21) and going straight, the stage of passing over the main nozzle hole smooth connection surface (13), the main nozzle hole smooth connection surface ( Due to the negative pressure generated on the 13) side, it draws toward the main nozzle hole smooth connection surface (13) side and bends, and quickly and strongly presses against the vortex chamber peripheral surface (12) of the vortex chamber (2) from an early stage. It is done and pushed to the left and right.
[0034]
  Along with this, the main air vortex (43) is pushed and expanded from the central space portion in the vortex chamber (2) toward the left and right space portions, and the air and fuel in the vortex chamber (2) The mixing performance is improved, and the air utilization rate is improved.
[0035]
  "Action 3. Collision and reflection of the pair of left and right side compressed air flows (42) and (42) are accelerated by the negative pressure pulling action of the main compressed air flow (41) on the main nozzle hole smooth connection surface (13). "
[0036]
  The above action2When the main compressed air flow (41) is strongly pressed against the peripheral surface (12) of the vortex flow chamber by the negative pressure drawing action of the main nozzle hole smooth connection surface (13), The side compressed air flow (42), (42) is impacted and reflected at the intersection (24) and pressed strongly from above to accelerate the collision / reflection.
[0037]
  As a result, both side air vortex flows (44) and (44) are spread over a wide range of both side space portions in the vortex flow chamber (12), so the mixing performance in the vortex flow chamber (2) The air utilization rate is further improved.
[0038]
  "Action 4. The above action1-3Synergism of "
  The above action1-3As a result, the mixing performance of air and fuel in the vortex chamber (2) is enhanced, and the air utilization rate is greatly improved. Thereby, PM (particulate material = particulate matter) could be reduced without deteriorating NOx (nitrogen oxide) in the combustion exhaust gas.
[0039]
  [B.6).The groove-passing air flow (45) that has passed through the micro-eddy current generating groove (32) generates a large amount of micro-eddy current (46).7).As the lateral width of the main air vortex flow (43) is expanded by the negative pressure pulling action of the main nozzle hole smooth connection surface (13), the micro vortex flow (46) generated in the groove passing air flow (45) is the main. Spreading widely in the transverse direction of the air vortex (43), and8).Accompanied by acceleration of collision and reflection between the pair of left and right side compressed air flows (42) and (42) by the negative pressure pulling action of the main compressed air flow (41) on the main nozzle hole smooth connection surface (13) Thus, due to the synergistic action of the three, the micro vortex flow (46) generated in the groove passing air flow (45) is diffused rapidly and widely in the lateral width direction of the side compressed air flow (42) (42). A large amount of micro vortex (46) diffuses rapidly over a wide range in the vortex chamber (21), increasing the contact rate and contact speed between air and fuel, and the ignition delay time from the start of fuel injection to the start of ignition To reduce the amount of NOx (nitrogen oxide) generated in the combustion exhaust gas. ]
[0040]
  "Action6. The groove passing air flow (45) passing through the micro eddy current generating groove (32) generates a large amount of micro eddy current (46). "
  As shown in FIG. 3 (C), the groove passing air flow (45) that has passed through the micro eddy current generating groove (32) jumps into the vortex chamber (21), and near the vortex chamber peripheral surface (12). The air in the space is engulfed by negative pressure and entrained while actively generating a large amount of micro eddy current (46).
[0041]
  "Action7. As the lateral width of the main air vortex flow (43) is expanded by the negative pressure pulling action of the main nozzle hole smooth connection surface (13), the micro vortex flow (46) generated in the groove passing air flow (45) is the main. It is diffused widely in the width direction of the air vortex (43). "
  “Action” of the above effect [I]2As shown in FIGS. 4 (C) and 4 (D), the lateral width of the main air vortex (43) is expanded by the negative pressure pulling action of the main nozzle hole smooth connection surface (13). go. Along with this, the micro vortex flow (46) generated in the groove passing air flow (45) is pushed in the lateral width direction of the main air vortex flow (43) and rapidly spreads widely.
[0042]
  [Action8. Accompanied by acceleration of collision and reflection between the pair of left and right side compressed air flows (42) and (42) by the negative pressure pulling action of the main compressed air flow (41) on the main nozzle hole smooth connection surface (13) Thus, the micro vortex flow (46) generated in the groove passing air flow (45) is rapidly and widely diffused in the lateral width direction of the side compressed air flow (42) (42). "
[0043]
  “Action” of the above effect [I]32 (A) and 2 (B), as shown in FIGS. 2 (A) and 2 (B), the main compressed air flow (41) at the main nozzle hole smooth connection surface (13) attracts the left and right sides by the negative pressure pulling action. Accelerates collision and reflection between compressed air flows (42) and (42).
  Along with this, as shown in FIG. 3C, the micro vortex flow (46) generated in the groove passing air flow (45) is involved in the collision and reflection between the side compressed air flows (42) and (42). Then, it rides on this collision / reflected flow and rapidly spreads widely in the lateral width direction in the side compressed air flow (42) (42).
[0044]
  "Action9. The above action6-8Synergy. "
  The above action6-8As a result of this synergistic action, a large amount of micro vortex flow (46) diffuses rapidly over a wide range in the vortex flow chamber (21), increasing the contact rate and contact speed between air and fuel, and starting ignition from the start of fuel injection. The ignition delay time is shortened, and the amount of NOx (nitrogen oxide) generated in the combustion exhaust gas is reduced.
  [E. Side nozzle surface for smooth connection (29) Side air vortex due to negative pressure generated on the side (44) Vortex chamber ( 2 ) The vortex chamber is as wide as it spreads over a wider area to the corners of the left and right sides of the interior. ( 2 ) The mixing performance and air utilization rate in the interior are dramatically improved, PM is greatly reduced, and the vortex chamber ( 2 ) Micro vortex flow in (46) Diffuses better and reduces NOx better. ]
[0045]
    ○ Invention 2. Claim 2. See FIG. 4 (C), (D), and FIG. 5 (B).
  The invention 2 has the following effects in addition to the effects [A] and [B] of the invention 1.
  [C. The main compressed air flow (41) is bent in multiple stages and is drawn more smoothly toward the side of the continuous inclined surface (16). The mixing performance and air utilization rate in the chamber (2) are improved and PM is further reduced, and the micro eddy current (46) in the vortex chamber (2) is better diffused to further reduce NOx. Reduce well. ]
[0046]
  As shown in FIG. 5 (B), the main nozzle hole smooth connection surface (13) is shown in FIGS. 4 (C) and (D) by the amount improved to the multi-step bent continuous inclined surface (16). The main compressed air flow (41) bends in a multi-stage bent continuous sloping surface (16) side and is bent more smoothly, and is strongly pressed by the peripheral surface (12) of the vortex chamber. It will be spread.
[0047]
  As a result, the above effects [A] and [B] can be improved by the amount that the main air vortex (43) spreads more widely from the central space portion in the vortex chamber (2) to the left and right side space portions. That is, the improvement of the mixing performance and the air utilization rate in the vortex chamber (2) was further improved, and PM (particulate material = particulate matter) could be further reduced.
[0048]
  Furthermore, when the main air vortex (43) spreads widely, the micro eddy current (46) generated in large quantities due to the air flow (45) passing through the grooves (32) and (32) for generating micro eddy currents is also The eddy current (43) spreads over a wider area and was able to reduce NOx (nitrogen oxide) better.
[0049]
    ○ Invention 3. Claim 3. See FIG. 4 (C), (D), and FIG. 5 (C).
  The invention 3 has the following effects in addition to the effects [A] and [B] of the invention 1.
  [D. As the main compressed air flow (41) is further smoothly drawn and bent toward the gentle convex curved surface (17), the main air vortex flow (43) is further expanded widely and the vortex chamber ( 2) Mixing performance and air utilization rate in the interior are further improved, PM is further reduced, and the micro eddy current (46) in the vortex chamber (2) is further diffused to further improve NOx. Reduce better. ]
[0050]
  As shown in FIG. 5 (C), the main compressed air shown in FIGS. 4 (C) and 4 (D) is obtained by improving the smooth connecting surface (17) of the main nozzle hole smooth connection surface (13). The flow (41) is more smoothly drawn toward the gentle convex curved surface (17) side, bent, and pressed more strongly against the peripheral surface (12) of the vortex flow chamber, and is further broadened to the left and right. Go.
[0051]
  As a result, the main air vortex flow (43) is further expanded widely from the central space portion to the left and right side space portions in the vortex flow chamber (2), and the mixing performance / air in the vortex flow chamber (2) is increased. The utilization rate was further improved and PM (particulate material = particulate matter) could be further reduced.
[0052]
  Furthermore, when the main air vortex (43) spreads widely, the micro eddy current (46) generated in large quantities due to the air flow (45) passing through the grooves (32) and (32) for generating micro eddy currents is also The eddy current (43) spreads over a wider area and was able to reduce NOx (nitrogen oxide) better.
[0053]
    ○ Invention 4. Claim 4. See FIG. 1, FIG. 3, FIG. 4 (C) and (D).
  This invention 4 is the above invention.2 or 3 effectsIn addition to the following effects.
  [E. The side air vortex flow (44) spreads over a wider area to the corners of the left and right side spaces in the vortex chamber (2) due to the negative pressure generated on the side nozzle smooth connection surface (29) side. However, the mixing performance and air utilization rate in the vortex chamber (2) are greatly improved, the PM is significantly reduced, and the micro vortex (46) in the vortex chamber (2) is better diffused. Reduce NOx better. ]
[0054]
  The side compressed air flow (42) shown in FIG. 3 is attracted by the negative pressure action by the side nozzle hole smooth connection surface (29) shown in FIG. 1, and is further strongly and strongly pressed against the peripheral surface (12) of the vortex chamber. It is done, and it is pushed to the left and right.
[0055]
  As a result, the side air vortex flow (44) extends to the corners of the left and right side space portions in the vortex flow chamber (2) in a wider range, and the mixing performance and air utilization obtained by the above effect [A] are obtained. The improvement of the rate was significantly improved, and PM (particulate material = particulate matter) could be reduced significantly without deteriorating NOx (nitrogen oxide) in the combustion exhaust gas.
[0056]
  Moreover, when the side air vortex (44) spreads widely, the micro eddy current (46) generated in a large amount by the groove passing air flow (45) of the micro eddy current generating groove (32) (32) is also The eddy current (44) spreads over a wider area and was able to reduce NOx (nitrogen oxide) better.
[0057]
    ○ Invention 5. Claim 5. See FIG. 1, FIG. 3 and FIG. 5 (B).
  This invention 5 is the above invention.1 orFoureffectIn addition to the following effects.
  [F. The side compressed air flow (42) is bent in multiple steps, and the side air vortex flow (44) is expanded more smoothly by bending more smoothly toward the continuous inclined surface (30) side. The mixing performance and air utilization rate in the chamber (2) are improved and PM is further reduced, and the micro eddy current (46) in the vortex chamber (2) is better diffused to further reduce NOx. Reduce well. ]
[0058]
  As shown in FIG. 5 (B), the side compressed air flow (42) shown in FIG. 3 is equivalent to the improvement of the side injection hole smooth connection surface (29) into a multi-step bent continuous inclined surface (30). Is bent more smoothly toward the side of the continuous inclined surface (30) and bent, and is strongly pressed by the peripheral surface (12) of the vortex chamber to be spread more widely to the left and right.
[0059]
  As a result, the side air vortex flow (44) is more widely spread from the central space portion in the vortex flow chamber (2) to the left and right side space portions, and the vortex flow chamber (2) obtained by the above effect [d] The improvement of the mixing performance and the air utilization rate in the inside is improved, and PM (particulate material = particulate material) can be further reduced.
[0060]
  Moreover, when the side air vortex (44) spreads widely, the micro eddy current (46) generated in a large amount by the groove passing air flow (45) of the micro eddy current generating groove (32) (32) is also The eddy current (44) spreads over a wider area and was able to reduce NOx (nitrogen oxide) better.
[0061]
    ○ Invention 6. Claim 6. See FIGS. 3 and 5C.
  This invention 6 is the above invention.1 orFoureffectIn addition to the following effects.
  [G. As the side compressed air flow (42) is further smoothly drawn and bent toward the gently convex curved surface (31) side, the side air vortex flow (44) is further expanded more widely and the vortex chamber ( 2) Mixing performance and air utilization rate in the interior are further improved, PM is further reduced, and the micro eddy current (46) in the vortex chamber (2) is better diffused to further reduce NOx. Reduce well. ]
[0062]
  As shown in FIG. 5 (C), the side compressed air flow (42) shown in FIG. 3 is gentle by the amount that the side nozzle hole smooth connection surface (29) is improved to a gentle convex surface (31). The curved surface is further smoothly drawn toward the convex curved surface (31), and is further strongly pressed against the peripheral surface (12) of the vortex chamber to be further broadened to the left and right.
[0063]
  As a result, the side air vortex flow (44) is further expanded widely in the left and right side space portions in the vortex flow chamber (2), and the vortex flow flow in the vortex flow chamber (2) obtained by the above effect [d] The improvement in the mixing performance and the air utilization rate of the material was further improved, and PM (particulate material = particulate material) could be further reduced.
[0064]
  Moreover, when the side air vortex (44) spreads widely, the micro eddy current (46) generated in a large amount by the groove passing air flow (45) of the micro eddy current generating groove (32) (32) is also The eddy current (44) spreads over a wider area and was able to reduce NOx (nitrogen oxide) better.
[0065]
DETAILED DESCRIPTION OF THE INVENTION
  Embodiments of a vortex chamber combustion chamber of a diesel engine according to the present invention will be described below with reference to the drawings.
    Embodiment 1 Claims 1, 4, and 7. See FIG. 1 to FIG.
[0066]
  FIG. 1 to FIG. 5 (A) show Embodiment 1 of the vortex chamber type combustion chamber of the diesel engine of the present invention. 1A is a vertical right side view of the nozzle mouthpiece, and FIG. 1B is a plan view of FIG. FIG. 1C is an enlarged view of a main part of the nozzle hole in FIG. 1D is a plan view of FIG. 1C, FIG. 1E is a bottom view of FIG. 1C, and FIG. 1F is a view taken in the direction of arrow F in FIG. FIG. 1G is a perspective view of the nozzle hole of FIG. 1C viewed from obliquely above, and FIG. 1H is a perspective view of the nozzle hole of FIG. 1C viewed obliquely from below.
[0067]
  FIG. 2 is a vertical right side view of a vortex chamber combustion chamber of a diesel engine. 3A is a longitudinal front view schematically showing the function of the main nozzle hole and the side nozzle hole of the nozzle hole, and FIG. 3B is a vertical right side view of FIG. 3A. FIG. 3C is a front view of a longitudinal section of a main part schematically showing the function of the micro eddy current generating groove.
[0068]
  FIG. 4 is a diagram schematically showing the function of the nozzle hole. 4A is a vertical right side view of a conventional nozzle and vortex chamber, and FIG. 4B is a cross-sectional view taken along line BB in FIG. 4A. 4C is a longitudinal right side view of the nozzle and vortex chamber of the present invention, and FIG. 4D is a cross-sectional view taken along line DD of FIG. 4C. FIG. 5A is a vertical right side view of the smooth connection surface of the nozzle hole.
[0069]
  In FIG. 2, reference numeral (51) denotes a cylinder of a water-cooled vertical multi-cylinder diesel engine, (52) denotes a cylinder head, (53) denotes a piston, and (54) denotes a vortex chamber base of the vortex chamber type combustion chamber.
  As shown in FIG. 1, a vortex chamber (2) is communicated with a main chamber (1) of a vortex chamber type combustion chamber of a diesel engine through a nozzle (3). The compressed air flow (6) that has been press-fitted into the vortex chamber (2) from the main chamber (1) through the nozzle (3) in the compression process turns into an air vortex (7) in the vortex chamber (2). To be configured. The fuel injection nozzle (8) faces the vortex chamber (2).
[0070]
  The shape of the nozzle hole (3) is formed by connecting the lateral sides of the pair of left and right side nozzle holes (22), (22) to the left and right sides of the main nozzle hole (21). The axial centers (23) and (23) of the side nozzle holes (22) and (22) are inclined to each other at a converging point and intersect at an intersection (24). This intersection (24) is located closer to the vortex chamber peripheral surface (12) of the vortex chamber (2) than the axis (25) of the main nozzle hole (21). The main injection hole (21) is formed in a cylindrical shape. The side injection holes (22) and (22) are formed in a truncated conical shape with an upper concavity.
[0071]
  Of the main nozzle hole peripheral edge (9) where the main nozzle hole (21) is connected to the vortex chamber (2), the main nozzle hole (21) is seen from the center (5) of the vortex chamber (2). In the outer peripheral side peripheral portion (10) located outside the axis (25), the outer peripheral portion (11) closer to the outer periphery of the main nozzle hole (21) and the vortex chamber peripheral surface (12) of the vortex chamber (2) The main nozzle hole smooth connection surface (13) for smoothly connecting the two is formed.
[0072]
  As shown in FIG. 5 (A), the vertical cross-sectional shape of the main nozzle hole smooth connection surface (13) is a vortex flow between the outer peripheral surface portion (11) of the main nozzle hole (21) and the vortex chamber (2). It is a one-step inclined surface that is gently inclined with respect to both the chamber peripheral surface (12). The angle at which the main nozzle hole smooth connection surface (13) is inclined with respect to the outer circumferential surface portion (11) of the nozzle hole (3) is in the range of 15.2 ° to 16 °.
[0073]
  In the inner peripheral side peripheral portion (14) located on the opposite side of the outer peripheral side peripheral portion (10) of the main injection hole end peripheral portion (9), the inner peripheral peripheral surface portion ( 15) and the vortex chamber peripheral surface (12) of the vortex chamber (2) can be directly connected with an acute angle.
[0074]
  In the peripheral edge portion (26) of the side nozzle hole where the side nozzle holes (22) are connected to the vortex chamber (2), the peripheral surface portion (28) of the side nozzle hole (22) and the vortex flow in the vortex chamber (2) A side injection hole smooth connection surface (29) for smoothly connecting the chamber peripheral surface (12) is formed.
[0075]
  As shown in FIG. 5 (A), the vertical cross-sectional shape of the side nozzle hole smooth connection surface (29) is the peripheral surface portion (28) of the side nozzle hole (22) and the vortex chamber circumference of the vortex chamber (2). It is a one-step inclined surface that is gently inclined with respect to both the surface (12). The angle at which the side injection hole smooth connection surface (29) is inclined with respect to the peripheral surface portion (28) of the side injection hole (22) is in the range of 15.2 ° to 16 °.
[0076]
  Grooves for generating micro eddy currents along all the boundary parts of the total of four boundary parts before and after the main nozzle hole (21) and the left and right side nozzle holes (22) and (22). (32) (32) ・ (33) (33) are formed, and the groove end of this micro eddy current generation groove (32) (32) ・ (33) (33) is the circumference of the vortex chamber (2). It is an opening in the surface (12).
[0077]
    ○ Other embodiments.
  In the second, third, and fourth embodiments described below, a part of the configuration of the first embodiment is changed as follows.
    Embodiment 2 Claims 2 and 5. See FIGS. 1 and 5B.
  FIG. 5B is a vertical right side view of the smooth connection surface of the nozzle hole according to the second embodiment.
[0078]
  In the second embodiment, a part of the configuration of the first embodiment is changed as follows.
  The vertical cross-sectional shape of the main nozzle hole smooth connection surface (13) gradually approaches from the outer peripheral surface portion (11) of the main nozzle hole (21) to the vortex chamber peripheral surface (12) of the vortex chamber (2). It consists of a multi-step bent continuous inclined surface (16).
[0079]
  The vertical cross-sectional shape of the side nozzle hole smooth connection surface (29) gradually approaches the peripheral surface portion (28) of the side nozzle hole (22) from the peripheral surface (12) of the vortex chamber (2). It consists of a multi-step bent continuous inclined surface (30).
[0080]
  In the main nozzle hole smooth connection surface (13) and the side nozzle hole smooth connection surface (29), the first inclined surface of the two-stage bent continuous inclined surfaces (16) is the injection port ( 3) The angle (Θ1) for inclining with respect to the peripheral surface portion (11) closer to the outer periphery is set to 16 °, and the angle (2 Θ2) is set to 6 °.
[0081]
    Embodiment 3 Claims 3 and 6. See FIGS. 1 and 5C.
  FIG. 5C is a vertical right side view of the smooth connection surface of the nozzle hole according to the third embodiment.
  The third embodiment is obtained by changing a part of the configuration of the first embodiment as follows.
[0082]
  The vertical cross-sectional shape of the main nozzle hole smooth connection surface (13) gradually approaches from the outer peripheral surface portion (11) of the main nozzle hole (21) to the vortex chamber peripheral surface (12) of the vortex chamber (2). Consists of gently convex curved surface (17).
[0083]
  The vertical cross-sectional shape of the side nozzle hole smooth connection surface (29) gradually approaches the peripheral surface portion (28) of the side nozzle hole (22) from the peripheral surface (12) of the vortex chamber (2). It consists of a gentle convex surface (31).
[0084]
    Embodiment 4 Claim2.3. See FIG.
  FIG. 6 shows the shape of a nozzle hole according to Embodiment 4 of the present invention. FIG. 6A is a vertical right side view of the nozzle hole. 6 (B) is a plan view of FIG. 6 (A), FIG. 6 (C) is a bottom view of FIG. 6 (A), and FIG. 6 (D) is a view taken in the direction of arrow D in FIG. 6E is a perspective view of the nozzle hole of FIG. 6A viewed from obliquely above, and FIG. 6F is a perspective view of the nozzle hole of FIG. 6A viewed from diagonally below.
[0085]
  In the fourth embodiment, a part of the configuration of the first, second, or third embodiment is changed as follows.
  That is, the side injection hole smooth connection surface (29) of the main injection hole smooth connection surface (13) and the side injection hole smooth connection surface (29) shown in FIG. The connection surface (13) is left.
[0086]
    ○ Other embodiments. The figure is omitted.
  In Embodiment 1-4, the shape of the main injection hole (21) is changed from a cylindrical shape to an elliptical column shape, a triangular column shape, a quadrangular column shape, a pentagonal column shape, a hexagonal column shape, or any other arbitrary shape. It is possible to change. It is also conceivable to change each of these columnar shapes to a tapered shape with an upward constriction.
[0087]
  The shape of the side nozzle hole (22) may be a truncated conical shape, a cylindrical shape, an elliptical column shape, a triangular column shape, a quadrangular column shape, a pentagonal column shape, a hexagonal column shape, or any other arbitrary shape. It is conceivable to change the shape. It is also conceivable to change each of these columnar shapes to a tapered shape with an upward constriction.
[Brief description of the drawings]
FIG. 1 to FIG. 5 (A) show Embodiment 1 of a vortex chamber type combustion chamber of a diesel engine of the present invention. 1A is a vertical right side view of the nozzle mouthpiece, and FIG. 1B is a plan view of FIG. FIG. 1C is an enlarged view of a main part of the nozzle hole in FIG. 1D is a plan view of FIG. 1C, FIG. 1E is a bottom view of FIG. 1C, and FIG. 1F is a view taken in the direction of arrow F in FIG. FIG. 1G is a perspective view of the nozzle hole of FIG. 1C viewed from obliquely above, and FIG. 1H is a perspective view of the nozzle hole of FIG. 1C viewed obliquely from below.
FIG. 2 is a vertical right side view of a vortex chamber combustion chamber of a diesel engine.
3A is a longitudinal front view schematically showing the functions of the main nozzle hole and the side nozzle hole of the nozzle hole, and FIG. 3B is a vertical right side view of FIG. 3A. FIG. 3C is a front view of a longitudinal section of a main part schematically showing the function of the micro eddy current generating groove.
FIG. 4 is a diagram schematically showing the function of a nozzle hole. 4A is a vertical right side view of a conventional nozzle and vortex chamber, and FIG. 4B is a cross-sectional view taken along line BB in FIG. 4A. 4C is a vertical right side view of the nozzle hole and the vortex chamber of the present invention, and FIG. 4D is a cross-sectional view taken along the line DD of FIG.
FIG. 5 is a vertical right side view of a smooth connection surface of an injection hole showing Embodiments 1, 2, and 3 of the present invention. 5A shows the first embodiment, FIG. 5B shows the second embodiment, and FIG. 5C shows the third embodiment.
FIG. 6 shows the shape of a nozzle hole according to Embodiment 4 of the present invention. FIG. 6A is a vertical right side view of the nozzle hole. 6 (B) is a plan view of FIG. 6 (A), FIG. 6 (C) is a bottom view of FIG. 6 (A), and FIG. 6 (D) is a view taken in the direction of arrow D in FIG. 6E is a perspective view of the nozzle hole of FIG. 6A viewed from obliquely above, and FIG. 6F is a perspective view of the nozzle hole of FIG. 6A viewed obliquely from below.
FIG. 7 shows the shape of a nozzle hole according to the prior art. FIG. 7A is a vertical right side view of the nozzle hole. 7B is a plan view of FIG. 7A, FIG. 7C is a bottom view of FIG. 7A, and FIG. 7D is a view as viewed from the direction of arrow D in FIG. 7A. FIG. 7E is a perspective view of the nozzle hole of FIG. 7A viewed from obliquely above, and FIG. 7F is a perspective view of the nozzle hole of FIG. 7A viewed from diagonally below.
[Explanation of symbols]
  DESCRIPTION OF SYMBOLS 1 ... Main chamber, 2 ... Swirl chamber, 3 ... Jet hole, 5 ... Center of vortex chamber, 6 ... Compressed air flow, 7 ... Air vortex flow, 8 ... Fuel injection nozzle, 9 ... Main nozzle end peripheral part, 10 ... Outer circumference side Peripheral part, 11 ... Outer peripheral surface part, 12 ... Eddy current chamber peripheral surface, 13 ... Main nozzle hole smooth connection surface, 14 ... Inner peripheral side peripheral part, 15 ... Inner peripheral side peripheral surface part, 16 ... Continuously bent in multiple steps Inclined surface, 17: gentle convex curved surface, 21 ... main injection hole, 22 ... side injection hole, 23 ... axis of side injection hole, 24 ... intersection, 25 ... axis of main injection hole, 26 ... end of side injection hole Peripheral part, 28 ... peripheral surface part, 29 ... side nozzle hole smooth connection surface, 30 ... multi-stage bent continuous inclined surface, 31 ... gentle convex curved surface 32 ... groove for generating micro eddy currents.

Claims (6)

The vortex chamber (2) is communicated with the main chamber (1) of the vortex chamber type combustion chamber of the diesel engine through the nozzle (3), and the vortex chamber (2) from the main chamber (1) through the nozzle (3) in the compression process. ) The compressed air flow (6) that has been press-fitted into the vortex chamber (2) is swirled as an air vortex flow (7) in the vortex chamber (2). ,
The shape of the nozzle hole (3) is formed by connecting the left and right side holes of the pair of left and right side nozzle holes (22) and (22) to the right and left sides of the main nozzle hole (21). 22) (22) axis centers (23) and (23) are inclined to each other and intersect at an intersection (24), and this intersection (24) is the axis (25) of the main nozzle hole (21). ) Is located closer to the peripheral surface (12) of the vortex chamber (2) than
In the vortex chamber combustion chamber of a diesel engine constructed
Of the main nozzle hole peripheral edge (9) where the main nozzle hole (21) is connected to the vortex chamber (2), the main nozzle hole (21) is seen from the center (5) of the vortex chamber (2). In the outer peripheral side peripheral portion (10) located outside the axis (25), the outer peripheral portion (11) closer to the outer periphery of the main nozzle hole (21) and the vortex chamber peripheral surface (12) of the vortex chamber (2) Forming the main nozzle hole smooth connection surface (13) to connect smoothly,
In the inner peripheral side peripheral portion (14) located on the opposite side of the outer peripheral side peripheral portion (10) of the main injection hole end peripheral portion (9), the inner peripheral peripheral surface portion ( 15) and the vortex chamber peripheral surface (12) of the vortex chamber (2) can be connected directly at an acute angle,
Along the front and right and left and right boundary portions of the front and right and left and right side nozzle holes (22) and (22), respectively, at least two front and left boundary portions, The micro eddy current generating grooves (32) and (32) are formed respectively, and the groove end portions of the micro eddy current generating grooves (32) and (32) are opened to the peripheral surface (12) of the vortex chamber (2),
Wherein the side nozzle hole end periphery (26) of the portion each side nozzle hole (22) is connected to the swirl chamber (2), the peripheral surface portion (28) and the swirl chamber of the side injection hole (22) a vortex (2) A side nozzle hole smooth connection surface (29) for smoothly connecting the chamber peripheral surface (12) is formed,
A vortex chamber type combustion chamber of a diesel engine characterized by comprising Swirl chamber type combustion chamber of the main chamber of the diesel engine (1) to the vortex chamber (2) the injection port (3) communicates through a main chamber in the compression process from (1) through the nozzle hole (3) swirl chamber (2 ) compressed air stream that has been pressed into (6), swirl chamber (2) in an air vortex (7) and is configured to pivot, the fuel injection nozzle into the swirl chamber (2) (8) ,
The shape of the nozzle hole (3) is formed to communicate with the lateral sides of the left and right of each side injection holes in both right and left lateral sides of the main nozzle hole (21) (22) (22), both sides nozzle hole ( 22) (22) axis centers (23) and (23) are inclined to each other and intersect at an intersection (24) , and this intersection (24) is the axis (25 ) of the main nozzle hole (21). ) Is located closer to the vortex chamber peripheral surface (12 ) than the vortex chamber ( 2 ) ,
In the vortex chamber combustion chamber of a diesel engine constructed
Said main injection hole (21) is a main nozzle hole end circumference of the portion leading to the swirl chamber (2) of the (9), the main injection hole viewed from the center (5) of the swirl chamber (2) (21) in the axial outer-side peripheral portion located outside the (25) (10), outer loop near the peripheral surface portion of the main nozzle hole (21) and (11) swirl chamber peripheral surface of the swirl chamber (2) and (12) Forming the main nozzle hole smooth connection surface (13) to connect smoothly ,
In the inner periphery side peripheral portion (14) located on the opposite side of the outer periphery side peripheral portion (10) of the main injection hole end peripheral portion ( 9 ) , the peripheral surface portion (14) closer to the inner periphery of the main injection hole (21) ( 15) and the vortex chamber peripheral surface (12) of the vortex chamber ( 2 ) can be connected directly at an acute angle,
The main nozzle hole (21) and left and right side injection holes (22) (22) and is out of the boundary portion of the total four places of the right and left front and rear forming and along a respective boundary of two portions of at least the front left and right, The micro eddy current generating grooves (32) and (32) are formed, respectively, and the groove end portions of the micro eddy current generating grooves (32) and (32 ) are opened to the vortex chamber peripheral surface (12) of the vortex chamber ( 2 ) ,
The vertical cross-sectional shape of the main nozzle hole smooth connection surface (13) gradually approaches from the outer peripheral surface portion (11) of the main nozzle hole (21) to the vortex chamber peripheral surface (12) of the vortex chamber (2). It consists of a multi-step bent continuous inclined surface (16). Swirl chamber type combustion chamber of the main chamber of the diesel engine (1) to the vortex chamber (2) the injection port (3) communicates through a main chamber in the compression process from (1) through the nozzle hole (3) swirl chamber (2 ) compressed air stream that has been pressed into (6), swirl chamber (2) in an air vortex (7) and is configured to pivot, the fuel injection nozzle into the swirl chamber (2) (8) ,
The shape of the nozzle hole (3) is formed to communicate with the lateral sides of the left and right of each side injection holes in both right and left lateral sides of the main nozzle hole (21) (22) (22), both sides nozzle hole ( 22) (22) axis centers (23) and (23) are inclined to each other and intersect at an intersection (24) , and this intersection (24) is the axis (25 ) of the main nozzle hole (21). ) Is located closer to the vortex chamber peripheral surface (12 ) than the vortex chamber ( 2 ) ,
In the vortex chamber combustion chamber of a diesel engine constructed
Said main injection hole (21) is a main nozzle hole end circumference of the portion leading to the swirl chamber (2) of the (9), the main injection hole viewed from the center (5) of the swirl chamber (2) (21) in the axial outer-side peripheral portion located outside the (25) (10), outer loop near the peripheral surface portion of the main nozzle hole (21) and (11) swirl chamber peripheral surface of the swirl chamber (2) and (12) Forming the main nozzle hole smooth connection surface (13) to connect smoothly ,
In the inner periphery side peripheral portion (14) located on the opposite side of the outer periphery side peripheral portion (10) of the main injection hole end peripheral portion ( 9 ) , the peripheral surface portion (14) closer to the inner periphery of the main injection hole (21) ( 15) and the vortex chamber peripheral surface (12) of the vortex chamber ( 2 ) can be connected directly at an acute angle,
The main nozzle hole (21) and left and right side injection holes (22) (22) and is out of the boundary portion of the total four places of the right and left front and rear forming and along a respective boundary of two portions of at least the front left and right, The micro eddy current generating grooves (32) and (32) are formed, respectively, and the groove end portions of the micro eddy current generating grooves (32) and (32 ) are opened to the vortex chamber peripheral surface (12) of the vortex chamber ( 2 ) ,
The vertical cross-sectional shape of the main nozzle hole smooth connection surface (13) gradually approaches from the outer peripheral surface portion (11) of the main nozzle hole (21) to the vortex chamber peripheral surface (12) of the vortex chamber (2). It consists of a gently convex curved surface (17). In the vortex chamber combustion chamber of the diesel engine according to claim 2 or 3 ,
In the peripheral edge portion (26) of the side nozzle hole where the side nozzle holes (22) are connected to the vortex chamber (2), the peripheral surface portion (28) of the side nozzle hole (22) and the vortex flow in the vortex chamber (2) A side nozzle hole smooth connection surface (29) for smoothly connecting the chamber peripheral surface (12) is formed. In the vortex chamber combustion chamber of the diesel engine according to claim 1 or 4,
The vertical cross-sectional shape of the side nozzle hole smooth connection surface (29) gradually approaches the peripheral surface portion (28) of the side nozzle hole (22) from the peripheral surface (12) of the vortex chamber (2). It consists of a multi-step bent continuous inclined surface (30). In the vortex chamber combustion chamber of the diesel engine according to claim 1 or 4,
The vertical cross-sectional shape of the side nozzle hole smooth connection surface (29) gradually approaches the peripheral surface portion (28) of the side nozzle hole (22) from the peripheral surface (12) of the vortex chamber (2). It consists of a gentle convex curved surface (31).

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