JP4252962B2 - Vortex chamber type diesel engine - Google Patents

Description

  The present invention relates to a vortex chamber type diesel engine, and more particularly to a vortex chamber type diesel engine capable of improving exhaust gas characteristics.

As a conventional vortex chamber type diesel engine, as in the present invention, a vortex chamber with a fuel injection nozzle facing the cylinder head is formed, and the main combustion chamber is communicated with the vortex chamber via an injection port so that There is one in which a plug is inserted (see, for example, Patent Document 1).
In this type of vortex chamber type diesel engine, the fuel injection pressure is lower than that of a direct injection type diesel engine, and an inexpensive fuel injection device can be used, and the startability can be improved by a glow plug. There is.

  However, in the conventional vortex chamber type diesel engine, only measures such as changing the shape of the nozzle hole are taken to improve the combustibility, and a glow plug having no edge on the surface is used. ing.

JP 2001-271648 A (see FIGS. 1 and 2)

The above prior art has the following problems.
<Problem> There is a limit to the improvement of exhaust gas characteristics.
When combustibility is improved only by measures such as changing the shape of the nozzle, even if PM (particulate matter) is reduced, nitrogen oxides that generally have a trade-off relationship with this increase in exhaust gas characteristics. There is a limit to the improvement.

  An object of the present invention is to provide a vortex chamber type diesel engine that can solve the above-described problems, that is, a vortex chamber type diesel engine that can improve exhaust gas characteristics.

(common part)
The common parts of the invention specifying matters of the inventions according to claims 1 to 3 are as follows.
As illustrated in FIG. 1A, a vortex chamber (3) facing the fuel injection nozzle (2) is formed in the cylinder head (1), and the vortex chamber (3) is provided with an injection port (4). In the vortex chamber type diesel engine in which the main combustion chamber (5) is communicated and the tip (7) of the glow plug (6) is inserted into the vortex chamber (3).
As shown in FIGS. 2 (G), (H) and FIGS. 3 (A) to 3 (D), the tip of the glow plug (6) is provided when the edge (8) is provided at the tip (7) of the plug (6). The edge (8) is formed by the surface periphery (9), the edge (8) located closer to the center of the glow plug than the edge (8) of the tip surface periphery (9) is formed, and the edge ( 8) faced the downstream side of the vortex (13) at the tip of the glow plug (6).
(Unique part)
The specific parts of the invention-specific matters of the invention according to claims 1 to 3 are as follows.
As for claim 1, as illustrated in FIGS. 2 (G) (H), a cross-shaped tip is formed on the tip surface (14) of the glow plug (6) directed downstream of the vortex (13) of the vortex chamber (3). A face groove (19) was formed, and an edge (8) positioned closer to the center of the glow plug than the edge (8) of the tip face peripheral edge (9) was formed at the opening edge (20) of the tip face groove (19). In the point.
With respect to claim 2, as illustrated in FIGS. 3A and 3B, a plurality of parallel grooves (on the tip surface of the glow plug 6 toward the downstream of the vortex 13 of the vortex chamber 3) 21), and the edge (8) located closer to the center of the glow plug than the edge (8) of the tip surface peripheral edge (9) is formed at the opening edge (22) of the parallel groove (21).
With respect to claim 3, as illustrated in FIGS. 3C and 3D, a plurality of plugs are provided on the tip surface (14) of the glow plug (6) directed downstream of the vortex (13) of the vortex chamber (3). A concentric annular groove (23) was provided, and an edge (8) located closer to the center of the glow plug than the edge (8) of the peripheral edge (9) was formed at the opening edge (24) of the annular groove (23). In the point.

( Effects common to the inventions according to claims 1 to 3 )
<Effect> The exhaust gas characteristics can be improved.
Nitrogen oxide can be reduced without increasing PM, and exhaust gas characteristics can be improved. The reason is considered as follows. Since the edge (8) becomes a heat point, the timing of ignition is advanced, and the combustion is performed slowly over a long time, so that the maximum combustion temperature is lowered and nitrogen oxides can be reduced. Moreover, since the heat point is the edge (8) provided at the tip (7) of the glow plug (6), the vortex flow (13) is different from the case where the heat point forming member is newly introduced into the vortex chamber (3). There is no hindrance to the flow. For this reason, combustion does not deteriorate and PM does not increase.

( Effect of the invention according to claim 1 )
<Effect> The flow of the vortex is not disturbed by the edge.
As illustrated in FIGS. 2G and 2H , a cross-shaped tip surface groove (19) is formed on the tip surface (14) of the glow plug (6) directed downstream of the vortex (13) of the vortex chamber (3). Since the edge (8) is formed by the opening edge (20) of the tip end surface groove (19), the vortex (13) does not collide with the edge (8), and the flow of the vortex (13) becomes the edge (8). Will not be disturbed.

( Effect of the invention according to claim 2 )
<Effect> The number of heat points is increased.
As illustrated in FIGS. 3A and 3B, a plurality of parallel grooves (21) are provided on the tip surface of the glow plug (6), and an edge (8) is formed at the opening edge (22) of the parallel grooves (21). ) Is formed, the total distance of the edge (8) is increased, and the number of occurrences of heat points is increased.

( Effect of the invention according to claim 3 )
<Effect> The number of heat points is increased.
As illustrated in FIGS. 3C and 3D, a plurality of concentric annular grooves (23) are provided on the tip surface (14) of the glow plug (6), and an opening edge (24 of the annular groove (23) is provided. ) To form the edge (8), the total distance of the edge (8) becomes long, and the number of heat point occurrences increases.

(Effect of the invention according to claim 4)
In addition to the effects of the invention according to any one of claims 1 to 3, the following effects are provided.
<Effect> Edge formation is easy.
As illustrated in FIGS. 2 (G) (H) and FIGS. 3 (A) to (D), the tip (7) of the glow plug (6) is formed in a cylindrical shape, and the tip of the glow plug (6) is formed. Since the circular edge (8) is formed at the periphery (9), the formation of the edge (8) is easy.

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram for explaining a vortex chamber type diesel engine according to a first embodiment of the present invention.

The outline of the first reference embodiment of the present invention is as follows.
As shown in FIG. 1 (A), a cylinder (28) is provided on the upper part of the cylinder block (27), and the cylinder head (1) is assembled on the upper part of the cylinder (28). A vortex chamber (3) facing the fuel injection nozzle (2) is formed in the cylinder head (1), and the main combustion chamber (5) is communicated with the vortex chamber (3) through the injection port (4). The tip (7) of the glow plug (6) is made to enter the vortex chamber (3).

The specific structure of the combustion chamber is as follows.
The cylinder head (1) is provided with a lower opening recess (29) upward from its lower surface, and a nozzle mouthpiece (30) is fitted into the lower opening recess (29) so that the lower opening recess (29) is located below. The opening hemisphere part (31) and the upper opening hemisphere part (32) of the nozzle mouthpiece (30) form a substantially spherical vortex chamber (3). A piston (33) is fitted into the cylinder (28), and a main combustion chamber (5) is formed in the cylinder (28) between the piston (33) and the cylinder head (1). The nozzle hole (4) is formed in the nozzle hole (30). The glow plug (6) is assembled to the cylinder head (1), and its tip (7) enters the lower opening hemisphere (31), and the vortex flow in the vortex chamber (3) against the fuel injection nozzle (2). (13) Located downstream. A cylinder jacket (34) is provided around the cylinder (28), a head jacket (35) is provided around the vortex chamber (3), and a water cooling jacket is formed by the cylinder jacket (34) and the head jacket (35). is doing.

The idea of the glow plug is as follows.
An edge (8) is provided at the tip (7) of the glow plug (6). Specifically, as shown in FIGS. 1 (B) and 1 (C), the tip (7) of the glow plug (6) is formed in a cylindrical shape, and circular at the peripheral edge (9) of the tip of the glow plug (6). The edge (8) is formed. The structure of the glow plug (6) may be modified and arranged at the same position downstream of the vortex chamber (3) in the vortex chamber (3) with respect to the fuel injection nozzle (2).

The structure of the glow plug used in the second to fifth reference embodiments and the first to third embodiments is as follows.
The glow plug (6) used in the first reference form of FIG. 1 has a tip portion (7) having a simple cylindrical shape and does not have a groove or a depression on the circumferential side or the tip surface. In contrast, the glow plugs used in the second to fifth reference embodiments and the first to third embodiments are different in the following points. The glow plug (6) used in the second reference form shown in FIGS. 2 (A) and 2 (B) has a tip portion (7) formed in a cylindrical shape, and extends along the circumferential direction on the circumferential side of the tip portion (7). A plurality of circumferential grooves (11) are formed, and a circular edge (8) is formed at the opening edge (12) of each circumferential groove (11). In the second reference embodiment , a circular edge (8) formed by the peripheral edge (9) of the tip surface of the glow plug (6) is formed by a circular edge formed by the opening edge (12) of each circumferential groove (11). (8) will be added.

The glow plug (6) used in the third reference form shown in FIGS. 2 (C) and (D) has a tip (7) formed in a cylindrical shape and directed downstream of the vortex (13) in the vortex chamber (3). A recess (15) is formed on the tip surface (14) of the glow plug (6), and an edge (8) is formed by the opening edge (16) of the recess (15). The recess (15) is a disk-shaped recess. In the third reference embodiment , a circular edge (8) formed by the opening edge (16) of the recess (15) is formed on the circular edge (8) formed by the peripheral edge (9) of the tip surface of the glow plug (6). ) Will be added.

The glow plug (6) used in the fourth embodiment shown in FIGS. 2 (E) and 2 (F) has a tip (7) formed in a cylindrical shape and directed downstream of the vortex (13) in the vortex chamber (3). The glow plug (6) is formed with a conical conical recess (17) whose entire front end surface is retracted, and an opening edge (18) of the conical recess (17) forms a circular edge (8). In the fourth reference embodiment , the circular edge (8) formed on the peripheral edge (18) of the tip surface of the glow plug (6) is formed at an acute angle.

The glow plug (6) used in the first embodiment shown in FIGS. 2 (G) (H) has a tip (7) formed in a cylindrical shape and directed downstream of the vortex (13) in the vortex chamber (3). A front end surface groove (19) is formed on the front end surface (14) of the glow plug (6), and an edge (8) is formed by an opening edge (20) of the front end surface groove (19). This front end surface groove (19) is formed in a cross shape. In this first embodiment , a circular edge (8) formed on the peripheral edge (9) of the tip surface of the glow plug (6) and an edge (8) formed on the opening edge (20) of the tip surface groove (19). ) Will be added. That is, in this first embodiment, the edge (8) located closer to the center of the glow plug than the edge (8) of the tip surface peripheral edge (9) is formed at the opening edge (20) of the tip surface groove (19), The edge (8) near the center of the glow plug is made to face the downstream side of the vortex (13) at the tip of the glow plug (6).

The glow plug (6) used in the second embodiment shown in FIGS. 3 (A) and 3 (B) has a tip (7) formed in a cylindrical shape and directed downstream of the vortex (13) in the vortex chamber (3). A plurality of parallel grooves (21) are provided on the tip surface of the glow plug (6), and an edge (8) is formed by an opening edge (22) of the parallel grooves (21). In this second embodiment , the edge (8) formed by the opening edge (22) of the parallel groove (21) on the circular edge (8) formed by the peripheral edge (9) of the tip surface of the glow plug (6). Will be added. That is, in the second embodiment, the opening edge (22) of the parallel groove (21) forms an edge (8) closer to the center of the glow plug than the edge (8) of the tip surface peripheral edge (9). The edge (8) closer to the center is made to face the downstream side of the vortex (13) at the tip of the glow plug (6).

The glow plug (6) used in the third embodiment shown in FIGS. 3 (C) and 3 (D) has a tip (7) formed in a cylindrical shape and directed downstream of the vortex (13) of the vortex chamber (3). A plurality of concentric annular grooves (23) are provided on the tip face (14) of the glow plug (6), and an edge (8) is formed by an opening edge (24) of the annular groove (23). In the third embodiment , the edge (8) formed by the opening edge (24) of the annular groove (23) is formed on the circular edge (8) formed by the front end surface periphery (9) of the glow plug (6). Will be added. That is, in this third embodiment, an edge (8) positioned closer to the center of the glow plug than the edge (8) of the tip surface peripheral edge (9) is formed at the opening edge (24) of the annular groove (23). The edge (8) near the center of the glow plug is made to face the downstream side of the vortex (13) at the tip of the glow plug (6).

The glow plug (6) used in the fifth reference embodiment shown in FIGS. 3 (E) and 3 (F) has a tip (7) formed in a cylindrical shape and directed downstream of the vortex (13) in the vortex chamber (3). A cylindrical columnar projection (25) is provided at the tip of the glow plug (6), and a circular edge (8) is formed at the peripheral edge portion (26) of the tip surface of the columnar projection (25). In the fifth reference embodiment , a circular edge (8) formed at the peripheral edge (9) of the tip surface of the glow plug (6) has a circular shape formed at the peripheral edge portion (26) of the columnar protrusion (25). Edge (8) will be added. That is, in the fifth reference embodiment, the edge (8) positioned closer to the center of the glow plug than the edge (8) of the tip surface periphery (9) is formed at the tip surface periphery (26) of the columnar protrusion (25). The edge (8) near the center of the glow plug is made to face the downstream side of the vortex (13) at the tip of the glow plug (6).

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure explaining the eddy current type diesel engine which concerns on 1st reference form of this invention, FIG. 1 (A) is a longitudinal cross-sectional view, FIG.1 (B) is a side view of the front-end | tip part of a glow plug, FIG. It is a C direction arrow directional view of Drawing 1 (B). FIG. 2A is a side view of the glow plug used in the second reference embodiment, and FIG. 2B is a diagram illustrating the glow plug used in the second to fourth reference embodiments and the first embodiment of the present invention. 2 (A) is a view in the B direction, FIG. 2 (C) is a side view of the glow plug used in the third embodiment, FIG. 2 (D) is a view in the direction D of FIG. 2 (C), and FIG. E) is a side view of a glow plug used in the fourth reference embodiment , FIG. 2F is a view taken in the direction of the arrow F in FIG. 2E, and FIG. 2G is a side view of the glow plug used in the first embodiment . FIG. 2 (H) is a view in the direction of arrow H in FIG. 2 (G). FIGS. 3A and 3B are diagrams illustrating glow plugs used in the second to third embodiments and the fifth reference embodiment of the present invention, FIG. 3A is a side view of the glow plug used in the second embodiment , and FIG. 3 (A) is a view in the B direction, FIG. 3 (C) is a side view of the glow plug used in the third embodiment , FIG. 3 (D) is a view in the direction D of FIG. 3 (C), and FIG. E) is a side view of the glow plug used in the fifth reference embodiment, and FIG. 3F is a view in the direction of arrow F in FIG.

Explanation of symbols

(1) Cylinder head
(2) Fuel injection nozzle
(3) Vortex chamber
(4) Spout
(5) Main combustion chamber
(6) Glow plug
(7) Tip
(8) Edge
(9) Tip edge
(13) Eddy current
(14) Tip surface
(19) Tip groove
(20) Open edge
(21) Parallel groove
(22) Open edge
(23) Annular groove
(24) Open edge

Claims (4)

A vortex chamber (3) facing the fuel injection nozzle (2) is formed in the cylinder head (1), and the main combustion chamber (5) is communicated with the vortex chamber (3) through the injection port (4). In the vortex chamber type diesel engine in which the tip (7) of the glow plug (6) has entered the vortex chamber (3),
In providing the edge (8) at the tip (7) of the glow plug (6),
An edge (8) is formed at the peripheral edge (9) of the tip surface of the glow plug (6),
A cross-shaped front end surface groove (19) is formed on the front end surface (14) of the glow plug (6) directed downstream of the vortex flow (13) of the vortex chamber (3), and the opening edge ( 20), an edge (8) located closer to the center of the glow plug than the edge (8) of the peripheral edge (9 ) of the tip surface is formed, and this edge (8) near the center of the glow plug is formed at the tip of the glow plug (6). A vortex chamber type diesel engine characterized by facing the downstream side of the vortex (13) . A vortex chamber (3) facing the fuel injection nozzle (2) is formed in the cylinder head (1), and the main combustion chamber (5) is communicated with the vortex chamber (3) through the injection port (4). In the vortex chamber type diesel engine in which the tip (7) of the glow plug (6) has entered the vortex chamber (3),
In providing the edge (8) at the tip (7) of the glow plug (6),
An edge (8) is formed at the peripheral edge (9) of the tip surface of the glow plug (6),
Vortex chamber (3) vortex parallel grooves (21) of the plurality of the distal end surface of the glow plug (6) toward the downstream (13) provided in the tip surface in the opening edge (22) of the parallel grooves (21) An edge (8) closer to the center of the glow plug than the edge (8) of the peripheral edge (9) is formed, and this edge (8) closer to the center of the glow plug is formed downstream of the vortex (13) at the tip of the glow plug (6). facing was a vortex chamber type diesel engine, characterized in that the. A vortex chamber (3) facing the fuel injection nozzle (2) is formed in the cylinder head (1), and the main combustion chamber (5) is communicated with the vortex chamber (3) through the injection port (4). In the vortex chamber type diesel engine in which the tip (7) of the glow plug (6) has entered the vortex chamber (3),
In providing the edge (8) at the tip (7) of the glow plug (6),
An edge (8) is formed at the peripheral edge (9) of the tip surface of the glow plug (6),
A plurality of concentric annular grooves (23) are provided on the tip surface (14) of the glow plug (6) directed downstream of the vortex flow (13) of the vortex chamber (3), and an opening edge ( 24) forms an edge (8) located closer to the center of the glow plug than the edge (8) of the peripheral edge (9 ) of the tip surface , and this edge (8) closer to the center of the glow plug is formed at the tip of the glow plug (6). A vortex chamber type diesel engine characterized by facing the downstream side of the vortex (13) . In the vortex chamber type diesel engine according to any one of claims 1 to 3 ,
A vortex chamber type diesel engine characterized in that a tip part (7) of a glow plug (6) is formed in a cylindrical shape and a circular edge (8) is formed at a peripheral edge (9) of the tip end surface of the glow plug (6). engine.

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