JP2018193924A - Reducing agent injection valve - Google Patents

Abstract

To provide a reducing agent injection valve that realizes a wider angle of injection of a reducing agent.SOLUTION: A reducing agent injection valve comprises an injection hole 51 for injecting urea water (a reducing agent), a supply flow passage for supplying the reducing agent to the injection hole 51, a valve element 32 for opening/closing the supply flow passage. The supply flow passage comprises a first passage part 53 and a second passage part 54 for passing the urea water in directions different from each other, and a merging part 55. The merging part 55 merges the urea water passed through the first passage part 53 and the urea water passed through the second passage part 54, and leads the merged urea water to the injection hole 51. A protruding member 45 protruding toward the injection hole 51 is arranged in the merging part 55.SELECTED DRAWING: Figure 3

Description

  The disclosure in this specification relates to a reducing agent injection valve that injects a reducing agent.

  Patent Document 1 discloses an injection valve that injects urea water to an upstream side of a purification device in an exhaust passage of an internal combustion engine. Then, ammonia produced from the urea water acts as a reducing agent on the reduction catalyst of the purification device, and NOx in the exhaust is reduced and purified.

JP 2014-238016 A

  Now, in recent years, it has been desired that the purifying apparatus is arranged close to the combustion chamber of the internal combustion engine in order to shorten the catalyst warm-up period at the time of cold start. Then, the distance between the injection valve and the purification device may have to be reduced. In this case, in order to spray the urea water uniformly on the exhaust inflow surface of the purification device, the spray from the injection valve is wide-angled. Is required.

  One object of the present invention is to provide a reducing agent injection valve that achieves a wide angle spray of reducing agent.

The reducing agent injection valve disclosed herein includes an injection hole (51) for injecting a reducing agent, a supply channel (30F) for supplying the reducing agent to the injection hole, and a valve body (32) for opening and closing the supply channel. A reducing agent injection valve for injecting a reducing agent to the upstream side of the purification device (20) in the exhaust passage (11a) of the internal combustion engine (10),
The supply flow path includes a first circulation part (53) and a second circulation part (54) that circulate the reducing agent in different directions, a reducing agent that circulates through the first circulation part, and a reducing agent that circulates through the second circulation part. And a joining part (55) for guiding the joined reducing agent to the nozzle hole,
The junction is a reducing agent injection valve in which a protruding member (45) protruding toward the injection hole is arranged.

  According to the reducing agent injection valve disclosed herein, when the reducing agents that have circulated in different directions merge, the main flow of the reducing agents of each other comes to join after colliding with the protruding member, A frontal collision is prevented from joining. Then, the reducing agent that has collided with the projecting member flows in a direction away from the projecting member as viewed from the projecting direction of the projecting member, spirals, and is then urged to join. As a result, the reducing agent after the merging is jetted from the nozzle hole while swirling so as to spread away from the center line of the nozzle hole, so that the angle of spraying of the reducing agent can be increased.

  The disclosed embodiments of the present specification employ different technical means to achieve each purpose. The reference numerals in parentheses described in the claims and this section exemplify the correspondence with the embodiments described later, and are not intended to limit the technical scope. The objects, features, and advantages disclosed in this specification will become more apparent with reference to the following detailed description and accompanying drawings.

The mimetic diagram showing the state where the reducing agent injection valve concerning a 1st embodiment was attached to the exhaust pipe. The figure which shows the single-piece | unit state of the reducing agent injection valve shown in FIG. Sectional drawing of the reducing agent injection valve shown in FIG. The enlarged view of FIG. The disassembled perspective view of FIG. FIG. 6 is a view taken in the direction of arrow VI in FIG. 5. The figure which shows the reducing agent injection valve which concerns on the 1st comparative example of 1st Embodiment. The VIII arrow line view of Drawing 4 showing typically the 1st distribution part, the 2nd distribution part, the merge part, and the projection member in a 1st embodiment. The figure which shows the reducing agent injection valve which concerns on the 2nd comparative example of 1st Embodiment. In 2nd Embodiment, the schematic diagram which looked at the 1st distribution part, the 2nd distribution part, the confluence | merging part, and the projection member from the nozzle hole side. In 3rd Embodiment, the schematic diagram which looked at the 1st distribution part, the 2nd distribution part, the confluence | merging part, and the projection member from the nozzle hole side. In 4th Embodiment, the schematic diagram which looked at the 1st distribution part, the 2nd distribution part, the confluence | merging part, and the projection member from the nozzle hole side. In 5th Embodiment, the schematic diagram which looked at the 1st distribution part, the 2nd distribution part, the confluence | merging part, and the protrusion member from the nozzle hole side. In 6th Embodiment, the schematic diagram which looked at the 1st distribution part, the 2nd distribution part, the confluence | merging part, and the protrusion member from the nozzle hole side. In 7th Embodiment, the schematic diagram which looked at the 1st distribution part, the 2nd distribution part, the confluence | merging part, and the protrusion member from the nozzle hole side.

  Hereinafter, a plurality of embodiments will be described with reference to the drawings. In each embodiment, portions corresponding to the matters described in the preceding embodiment may be denoted by the same reference numerals and redundant description may be omitted. In each embodiment, when only a part of the configuration is described, the other configurations described above can be applied to other portions of the configuration.

(First embodiment)
An internal combustion engine 10 shown in FIG. 1 is mounted on a vehicle and functions as a travel drive source. Exhaust gas discharged from the combustion chamber of the internal combustion engine 10 flows through the exhaust passage 11a inside the exhaust pipe 11, and after being purified by the purification device 20 or the like, is discharged to the atmosphere. The purification device 20 has a function of reducing and purifying NOx (nitrogen oxide) contained in exhaust gas and a function of collecting particulate matter (PM). The purification device 20 includes a passage member 21 connected to the exhaust pipe 11, a base material 22 accommodated in the passage member 21 to purify exhaust, and a catalyst layer supported by the base material 22.

  The substrate 22 is made of ceramic formed in a honeycomb shape, and the outer shape of the substrate 22 is a columnar shape extending in the exhaust flow direction. An end face on the upstream side of the exhaust flow among the both end faces of the cylinder of the base material 22 functions as the exhaust inlet 22a. The catalyst layer contains a reduction catalyst component and an adsorption component described below. The reduction catalyst component is a component for reducing NOx contained in the exhaust, and for example, platinum is used. Zeolite is used as the adsorbing component and physically adsorbs ammonia described later.

  A reducing agent injection valve 30 for injecting a reducing agent is attached to the upstream side of the purification device 20 in the exhaust pipe 11. In this embodiment, a liquid reducing agent (for example, urea water) is used. The urea water injected into the exhaust passage 11a is hydrolyzed by exhaust heat. As a result, gaseous ammonia is generated in the exhaust passage 11a. The generated ammonia flows into the base material 22 from the exhaust inlet 22a and is adsorbed by the catalyst layer. Specifically, ammonia is physically adsorbed on the adsorbing component contained in the catalyst layer.

  Part of the adsorbed ammonia reduces NOx contained in the exhaust gas on the reduction catalyst component contained in the catalyst layer. Therefore, strictly speaking, in the state of the urea water injected from the reducing agent injection valve 30, it cannot be said to be a reducing agent, and ammonia generated by hydrolysis of the urea water acts as a reducing agent. However, in this embodiment, urea water that can be said to be a raw material for ammonia may be simply referred to as a reducing agent, and this urea water corresponds to the reducing agent described in the claims.

  The reducing agent injection valve 30 includes a body 31, a valve body 32, and an electric actuator 33. The body 31 houses the valve body 32 and the electric actuator 33 therein. When the valve element 32 is opened by electromagnetic attraction generated by energization of the electric actuator 33, urea water is injected from the injection hole 51 (see FIG. 3) formed in the body 31 into the exhaust passage 11a.

  A part of the body 31 is located in the exhaust passage 11a and exposed to the exhaust. A nozzle hole 51 for injecting urea water is formed in a portion of the body 31 that is exposed to the exhaust gas. Although the reducing agent injection valve 30 according to the present embodiment includes one injection hole 51, a plurality of reduction holes may be provided. The urea water injected from the nozzle hole 51 forms a conical spray F (see FIG. 1).

  The vehicle is equipped with a tank 30T that stores urea water and a pump 30P that pumps the urea water stored in the tank 30T to the reducing agent injection valve 30. The pump 30P is an electric type driven by an electric motor. By controlling the electric power supplied to the pump 30P, the pressure of the urea water supplied to the reducing agent injection valve 30 is controlled, and consequently the injection pressure of the urea water from the nozzle hole 51 is controlled.

  An electronic control unit (not shown) (hereinafter referred to as ECU) controls the start and stop of the injection of urea water from the nozzle hole 51 by controlling energization to the electric actuator 33. Furthermore, ECU controls the injection pressure of urea water by controlling the electric power supplied to the electric motor which pump 30P has. The reducing agent injection system according to the present embodiment includes an ECU and a reducing agent injection valve 30. The exhaust purification system according to the present embodiment includes a purification device 20 in addition to the reducing agent injection system.

  Next, the structure of the reducing agent injection valve 30 will be described in detail with reference to FIG.

  The electric actuator 33 of the reducing agent injection valve 30 includes an electromagnetic coil 331, a fixed core 332, and a movable core 333. When the electromagnetic coil 331 is energized, a magnetic flux is generated in the fixed core 332 and the movable core 333, and the movable core 333 is attracted to the fixed core 332 by the electromagnetic attraction force by the magnetic flux. Since the movable core 333 is attached to the valve body 32, the valve body 32 reciprocates in the direction of the central axis C together with the movable core 333.

  The body 31 of the reducing agent injection valve 30 includes a proximal end body 311, a nonmagnetic member 312, a distal end body 313, a magnetic member 314, a plate member 40, and an injection hole member 50. The proximal end body 311 has a cylindrical shape that holds the fixed core 332 therein. The nonmagnetic member 312 is disposed between the proximal end body 311 and the distal end body 313 and blocks the magnetic flux described above. The distal end side body 313 has a cylindrical shape that accommodates the valve body 32 therein. A seat surface 313 s on which a seat surface 32 s provided at the tip of the valve element 32 is seated is formed on the inner circumferential surface of the tip body 313 (see FIG. 3).

  The urea water supplied from the base end of the base end side body 311 passes through the internal passage 311 a of the base end side body 311, the internal passage 332 a of the fixed core 332, the internal passage 333 a of the movable core 333, and the internal passage 32 a of the valve body 32. Circulate in order. Thereafter, the urea water in the internal passage 32a flows out from the outlet 32b (see FIG. 2) and the outlet 32c (FIG. 3) formed on the side wall of the valve body 32. Then, an annular passage 313 a formed between the inner peripheral surface of the distal end side body 313 and the outer peripheral surface of the valve body 32, and a joining passage 313 b along the distal end of the valve body 32 circulate in order. The annular passage 313a is opened and closed by the valve body 32 being seated on and off the seat surface 313s. The merge passage 313b merges the annularly distributed urea water in the annular passage 313a and distributes it in a disk shape including the central axis C. The central axes of the annular passage 313 a, the merge passage 313 b, and the injection hole 51 coincide with the central axis C of the valve body 32.

  As shown in FIGS. 2 to 4, the plate member 40 and the nozzle hole member 50 are attached to the tip of the tip side body 313. The plate member 40 is disposed between the distal end side body 313 and the injection hole member 50. For example, the front end body 313, the plate member 40, and the injection hole member 50 are joined by welding.

  The plate member 40 includes a disk-shaped plate 41 that covers the junction passage 313 b from the injection hole side, and a cylindrical portion 42 that extends from the outer peripheral end of the plate 41 along the outer peripheral surface of the distal end side body 313. The plate 41 is formed with a first through hole 43 and a second through hole 44 that communicate with the junction passage 313b. The first through hole 43 and the second through hole 44 are formed in a state of being separated from each other without being communicated within the plate 41.

  As shown in FIG. 5, the first through hole 43 and the second through hole 44 have an arc shape extending around the central axis C. The arc length of the first through hole 43 and the arc length of the second through hole 44 are the same. The radial positions of the outer peripheral edges of the first through holes 43 and the second through holes 44 are the same as the radial positions of the outer peripheral edges of the merge passage 313b. The surface of the plate 41 on the side opposite to the injection hole has a flat shape that extends perpendicularly to the central axis C. A protruding member 45 that protrudes toward the injection hole 51 is formed on the surface of the plate 41 on the injection hole side. The plate 41 is made of metal, and the protruding member 45 may be manufactured by pressing the plate 41, may be manufactured by cutting, or may be manufactured by welding to the plate 41.

  One injection hole 51 for injecting urea water is formed in the injection hole member 50. The injection hole 51 has a shape that extends in the direction of the central axis C along the central axis C of the injection hole member 50, and has a shape in which the passage cross-sectional area increases as it becomes downstream (see FIG. 5). The downstream end opening 51b of the nozzle hole 51 is circular with the central axis C as the center. An annular groove 52 surrounding the downstream end opening 51b is formed on the end surface of the nozzle hole member 50 opposite to the plate member 40. By forming the annular groove 52, urea water is prevented from adhering to the peripheral portion of the downstream end opening 51b in the end face of the injection hole member 50 due to surface tension.

  A first flow part 53 and a second flow part 54 that extend in different directions and flow urea water are formed on the surface of the nozzle hole member 50 that contacts the plate 41. These circulation portions have a groove shape opened to the plate 41 side, and the groove opening is covered with the plate 41. The first flow part 53 and the second flow part 54 are arranged so as to extend on the same plane, extend linearly in the radial direction, and extend in parallel to each other.

  Furthermore, the surface of the nozzle hole member 50 that contacts the plate 41 is joined with urea water that has circulated through the first circulation part 53 and urea water that has circulated through the second circulation part 54 at the center of the nozzle hole member 50, A joining portion 55 that guides the joined urea water to the nozzle hole 51 is formed. The merge part 55 has a vortex generator 55a and a vortex outlet 55b (see FIG. 4).

  The vortex generator 55a has a cylindrical shape extending in the direction of the central axis C. The vortex generating part 55 a communicates with the downstream end of the first circulation part 53 and the downstream end of the second circulation part 54. In the following description, the inlet flowing from the first circulation part 53 to the vortex generating part 55a is the first inlet 53a, and the inlet flowing from the second circulation part 54 to the vortex generating part 55a is the second inlet 54a. Call it.

  The vortex outflow portion 55b has a conical shape extending along the central axis C, and has a shape in which the cross-sectional area of the passage becomes smaller toward the downstream side. The upstream end of the vortex outlet 55 b communicates with the downstream end of the vortex generator 55 a, and the downstream end of the vortex outlet 55 b communicates with the upstream end of the nozzle hole 51.

  The protruding member 45 formed on the plate 41 is disposed in the vortex generating portion 55a. The protruding member 45 has a shape protruding perpendicularly to the surface of the plate 41, that is, a shape protruding in the direction of the central axis C (see FIGS. 3 and 4). The shape of the protruding member 45 viewed from the nozzle hole side is a quadrangle having four apexes (see FIG. 8). The protruding member 45 is disposed at a position facing the first inlet 53a and the second inlet 54a. When viewed from the flow direction of the first flow part 53, the protruding member 45 is sized to cover the first inflow port 53a, and the area of the protruding member 45 projected in the flow direction is larger than the area of the first inflow port 53a. large. When viewed from the flow direction of the second flow part 54, the protruding member 45 is sized to cover the second inlet 54a, and the area of the protruding member 45 projected in the flow direction is larger than the area of the first inlet 53a. large.

  The protruding length L1 of the protruding member 45 is longer than the depth dimension L2 of the first flow part 53 and the depth dimension L2 of the second flow part 54 in the opening / closing operation direction (center axis C direction) of the valve body 32 (see FIG. 4). That is, the protruding end surface 45a of the protruding member 45 is located closer to the injection hole than the first inflow port 53a and the second inflow port 54a. The depth dimension L2 of the first circulation part 53 and the depth dimension L2 of the second circulation part 54 are the same. Moreover, the protrusion length L1 of the protrusion member 45 is shorter than the depth dimension L3 of the junction part 55 (refer FIG. 4).

  The length L4 in the flow path direction of the protruding member 45, that is, the length dimension of the protruding member 45 in the flow direction of the first flow portion 53 and the second flow portion 54 is longer than the diameter D1 of the injection hole 51 (see FIG. 4). . Moreover, the flow path direction length L4 of the protrusion member 45 is shorter than the diameter of the confluence | merging part 55 (refer FIG. 4).

  The vortex generating part 55a has a shape in which the width dimension L5 of the first circulation part 53 and the width dimension L5 of the second circulation part 54 are widened as seen from the protruding direction of the protruding member 45. That is, the diameter D2 of the vortex generator 55a is larger than the width dimension L5 (see FIGS. 6 and 8). The width dimension L5 of the first circulation part 53 and the width dimension L5 of the second circulation part 54 are the same.

  The width dimension L6 of the protrusion member 45 (see FIG. 8), that is, the dimension in the direction perpendicular to the plane of FIG. 4 is the width dimension L5 of the first inlet 53a and the width of the second inlet 54a as viewed from the protrusion direction of the protrusion member 45. Larger than dimension L5.

  As shown in FIG. 8, the protruding member 45 has a first inclined surface 45t1 and a second inclined surface 45t2. The first inclined surface 45t1 has a shape that is inclined so as to gradually increase the width dimension seen from the protruding direction of the protruding member 45 from the first inflow port 53a toward the center of the protruding member 45. The second inclined surface 45t2 has a shape inclined so as to gradually increase the width dimension viewed from the protruding direction of the protruding member 45 from the second inflow port 54a toward the center of the protruding member 45. The first inclined surface 45t1 and the second inclined surface 45t2 have shapes that are curved in a direction to be recessed toward the center side of the protruding member 45.

  Next, the flow of urea water from the merging passage 313b to the downstream end opening 51b will be described in detail with reference to FIGS. In the following description, a portion of the first through hole 43 that communicates with the first flow portion 53 is referred to as a first communication portion 43a, and a portion of the second through hole 44 that communicates with the second flow portion 54 is a second. It is called the communication part 44a. Each of the first through hole 43 on the one end side and the other end side from the first communication portion 43a is referred to as a first passage 43b, 43c, and the second through hole 44 on the one end side from the second communication portion 44a. These portions and the other end portion are referred to as second passages 44b and 44c. The first communication portion 43a is disposed in the central portion of the first through hole 43, and the two first passages 43b and 43c have the same passage length. Similarly, the second communication portion 44a is disposed in the central portion of the second through hole 44, and the passage lengths of the two second passages 44b and 44c are the same.

  The urea water that has joined from the annular passage 313 a to the joining passage 313 b flows into the first through hole 43 and the second through hole 44. Specifically, the urea water located immediately above the first through hole 43 and the second through hole 44 in the junction passage 313 b flows into the first through hole 43 and the second through hole 44 as they are. As shown by the arrow F1 in FIG. 5, the urea water at a position that is off from the position directly above flows along the surface of the plate 41 and flows into the first through hole 43 and the second through hole 44.

  The urea water that has flowed into the first through hole 43 flows toward the first communication portion 43a. And the urea water (refer arrow F2) which flows toward the 1st communication part 43a from the one end side of the circular arc of the 1st through-hole 43, and the urea water (arrow F3) which flows toward the 1st communication part 43a from the other end side And a frontal collision at the first communication portion 43a. That is, the urea water that has flowed through the two first passages 43b and 43c collides with each other at the first communication portion 43a. Thereafter, the collided urea water flows into the radially outer end of both ends of the first flow part 53.

  Similarly, urea water that flows from one end of each arc end of the second through hole 44 toward the second communication portion 44a and urea water that flows from the other end toward the second communication portion 44a are connected to the second communication portion. Collision at part 44a. That is, the urea water that has flowed through the two second passages 44b and 44c collides frontally at the second communication portion 44a. Thereafter, the collided urea water flows into the radially outer end of both ends of the second flow portion 54.

  The urea water that has flowed into each of the first flow part 53 and the second flow part 54 flows toward the vortex generation part 55 a of the merge part 55. And the urea water (refer arrow F4) which flowed through the 1st distribution part 53 and flowed into the vortex production | generation part 55a from the 1st inflow port 53a, and the 2nd circulation part 54 flowed through the 2nd circulation part 54a and the vortex production | generation part 55a. The urea water (see arrow F5) that flows into the vortex collides at the vortex generator 55a.

  Strictly speaking, the main flow of the urea water first collides with the protruding member 45 in the vortex generating portion 55a, and flows so as to wind a vortex along the first inclined surface 45t1 and the second inclined surface 45t2 (arrow F6). F7). Then, urea water that collides with the first inclined surface 45t1 (see arrow F6) and urea water that collides with the second inclined surface 45t2 (see arrow F7) collide with each other at the vortex generator 55a and merge. To do.

  The swirling urea water circulates in order to the vortex outflow portion 55b and the nozzle hole 51 while increasing the diameter of the vortex, that is, expanding outward in the radial direction, and thereafter expands outward in the radial direction. Injected from the downstream end opening 51b while going off. For this reason, the angle of the spray F increases because it tends to expand radially outward even immediately after injection from the downstream end opening 51b.

  The internal passages 311a, 332a, 333a, 32a, the annular passage 313a, the merge passage 313b, the first through hole 43, the second through hole 44, the first flow portion 53, the second flow portion 54, and the merge portion 55 are jetted. This corresponds to the supply flow path 30 </ b> F that supplies the reducing agent to the holes 51. The first through hole 43 causes the urea water flowing from one end side and the urea water flowing from the other end side to collide with each other, and the first flow path portion that guides the urea water after the collision to the first circulation portion 53. It corresponds to. The second through hole 44 corresponds to a second flow path portion that collides the urea water flowing in from one end side with the urea water flowing in from the other end side, and guides the urea water after the collision to the second flow portion 54. To do.

  As described above, according to the present embodiment, the supply flow path 30 </ b> F that supplies urea water to the nozzle hole 51 has the first circulation part 53 and the second circulation part 54 that cause the urea water to circulate in different directions, and the merging part 55. And have. The merging unit 55 merges the urea water circulated through the first flow unit 53 and the urea water circulated through the second flow unit 54, and guides the merged urea water to the nozzle hole 51. A projecting member 45 that protrudes toward the injection hole 51 is disposed in the joining portion 55.

  Accordingly, when the urea waters flowing in different directions merge, the urea waters merge after colliding with the projecting member 45, and the urea waters are prevented from colliding due to a frontal collision. Then, as shown by arrows F6 and F7 in FIG. 8, the urea water that collided with the protruding member 45 flows to the outside in the radial direction of the vortex generating portion 55a when viewed from the protruding direction of the protruding member 45, and then spirals. Prompted to do. As a result, the combined urea water is jetted from the nozzle hole 51 while swirling in the direction of expanding in the radial direction, and the spray F can be widened.

  In addition, in the 2nd comparative example shown in FIG. 9, the protrusion member 45 which concerns on this embodiment is abolished. In this case, the vortex component resulting from the collision with the protruding member 45 as indicated by arrows F6 and F7 in FIG. 8 is not generated. Therefore, according to this embodiment provided with the protrusion member 45, the spray F becomes a wide angle compared with the 2nd comparative example which abolished the protrusion member 45. FIG.

  Further, in the present embodiment, the vortex generating portion 55a of the merging portion 55 has a shape in which the width dimension L5 of the first flow portion 53 and the width dimension L5 of the second flow portion 54 are widened when viewed from the protruding direction of the protruding member 45. It is. Therefore, the space necessary for the urea water to swirl in the vortex generating portion 55a can be sufficiently secured, and the vortex generation of the urea water can be promoted. As a result, the spray F can be promoted to expand in the radial direction.

  Furthermore, in this embodiment, the width dimension L6 of the protrusion member 45 is larger than the width dimension L5 of the first inlet 53a and the width dimension L5 of the second inlet 54a as viewed from the protruding direction of the protrusion member 45. According to this, it is possible to suppress a frontal collision between the main flow of urea water flowing into the vortex generating portion 55a from the first inlet 53a and the main flow of urea water flowing into the vortex generating portion 55a from the second inlet 54a. . For this reason, the hindrance to the generation of vortex due to the frontal collision can be suppressed and the spray F can be promoted to expand in the radial direction.

  Furthermore, in the present embodiment, the protruding end surface 45a of the protruding member 45 is located closer to the injection hole 51 than the first inlet 53a and the second inlet 54a. Therefore, of the urea water that has flowed into the vortex generator 55a from the first inlet 53a and the second inlet 54a, the component that flows into the vortex outlet 55b without colliding with the protruding member 45, that is, sufficient vortex generation occurs. The component which flows in into the vortex outflow part 55b without being reduced can be decreased. Therefore, the vortex generation of urea water can be promoted, and consequently, the spray F can be promoted to expand in the radial direction.

  Further, in the present embodiment, the protruding member 45 has a first inclined surface 45t1 and a second inclined surface 45t2. The first inclined surface 45t1 has a shape that is inclined so as to gradually increase the width dimension L6 viewed from the protruding direction of the protruding member 45 from the first inflow port 53a toward the center of the protruding member 45. The second inclined surface 45t2 has a shape inclined so as to gradually increase the width dimension L6 viewed from the protruding direction of the protruding member 45 from the second inflow port 54a toward the center of the protruding member 45.

  Therefore, the urea water flowing into the vortex generator 55a from the first inflow port 53a and colliding with the first inclined surface 45t1 flows along the first inclined surface 45t1, so that the flow direction is bent radially outward. Vortexing is promoted. Similarly, urea water that has flowed into the vortex generator 55a from the second inlet 54a and collided with the second inclined surface 45t2 flows along the second inclined surface 45t2, so that the flow direction is radially outward. Bending and swirling is facilitated. Therefore, the vortex generation of urea water can be promoted, and consequently, the spray F can be promoted to expand in the radial direction.

  Furthermore, in the present embodiment, the first inclined surface 45t1 and the second inclined surface 45t2 have shapes that are curved so as to be recessed toward the center side of the protruding member 45. Therefore, the urea water that flows along the first inclined surface 45t1 and the second inclined surface 45t2 is urged to become a vortex flow along the curved surface (see FIG. 8). Therefore, the vortex generation of urea water can be further promoted.

  Further, in the present embodiment, the first flow part 53 and the second flow part 54 are arranged on the same plane, that is, on a plane perpendicular to the central axis C, and the protruding member 45 is arranged in the flow direction of the first flow part 53 and the first flow direction. 2 is a shape protruding perpendicularly to the flow direction of the flow portion 54. Therefore, the inflow direction flowing from the first inlet 53a into the vortex generator 55a and the inflow direction flowing into the vortex generator 55a from the second inlet 54a are on the same plane, that is, on a plane perpendicular to the central axis C. Placed in. Therefore, it is urged that the spiral of urea water flowing in from the first inlet 53a and the spiral of urea water flowing in from the second inlet 54a are located on the same plane. Therefore, it is promoted that the urea water after merging is jetted from the nozzle hole 51 while swirling in a direction in which the urea water expands in the radial direction, and widening of the spray F can be promoted.

  Furthermore, in this embodiment, the 1st through-hole 43 which connects the confluence | merging channel | path 313b and the 1st distribution part 53, and the 2nd through-hole 44 which connects the confluence | merging path 313b and the 2nd distribution | circulation part 54 are provided. The first through hole 43 includes a first communication portion 43a and two first passages 43b and 43c. The first communication part 43 a communicates with the downstream ends of the two first passages 43 b and 43 c and also communicates with the first circulation part 53. The two first passages 43b and 43c cause urea water to circulate in different directions and lead to the first communication portion 43a for collision. The second communication portion 44 a communicates with the downstream ends of the two second passages 44 b and 44 c and also communicates with the second flow portion 54. The two second passages 44b and 44c cause urea water to circulate in different directions and lead to and collide with the second communication portion 44a.

  According to this, after the urea water collides with each of the first communication portion 43a and the second communication portion 44a, the urea water collides with the junction portion 55. Therefore, the urea water that circulates through the first circulation part 53 and the second circulation part 54 can be brought into a state in which many vortex components are included, that is, a state in which turbulent energy is high. As a result, the vortex generation of the urea water in the vortex generator 55a can be promoted, and as a result, the spray F can be promoted to expand in the radial direction. It can be said that the above-described turbulent energy is the sum of the kinetic energy of a plurality of vortices contained in urea water.

  In the first comparative example shown in FIG. 7, the first through hole 43 and the second through hole 44 according to the present embodiment are replaced with the first through hole 43P and the second passage 44b in which the first passages 43b and 43c are abolished. 44c is replaced with the second through hole 44P which has been abolished. In this case, since the urea water distributed in the merge passage 313b flows evenly from the periphery of the first through hole 43 and the second through hole 44, the urea water collides with the first through hole 43 and the second through hole 44. Hardly occurs. On the other hand, in the present embodiment, the first through hole 43P has the first passages 43b and 43c, and the second through hole 44P has the second passages 44b and 44c, so the first through hole 43 and the second through hole At 44, the urea water is urged to collide.

  Furthermore, in the present embodiment, the first communication portion 43a is disposed in the central portion of the first through hole 43, so that the two first passages 43b and 43c have the same passage length. In other words, of the channel lengths of the first through holes 43 (first channel portions), the channel length on one end side from the first communication portion 43a and the channel length on the other end side from the first communication portion 43a are: Are the same. Therefore, the collision position of the urea water can be set to the first communication portion 43 a, and the urea water immediately after the collision can be urged to flow into the first flow portion 53.

  Similarly, by disposing the second communication portion 44a at the center portion of the second through hole 44, the passage lengths of the two second passages 44b and 44c are made the same. In other words, of the channel length of the second through hole 44 (second channel portion), the channel length on one end side from the second communication portion 44a and the channel length on the other end side from the second communication portion 44a are: Are identical. Therefore, the collision position of the urea water can be the second communication portion 44a, and the urea water immediately after the collision can be encouraged to flow into the second flow portion 54.

(Second Embodiment)
In the protruding member 45 according to the first embodiment, the first inclined surface 45t1 and the second inclined surface 45t2 have a curved shape that is recessed toward the center side of the protruding member 45. On the other hand, in the protruding member 451 according to the present embodiment, as shown in FIG. 10, the first inclined surface 45t1 and the second inclined surface 45t2 have a flat tapered shape. Note that the first inclined surface 45t1 and the second inclined surface 45t1 according to the present embodiment are different in that the width dimension viewed from the protruding direction of the protruding member 45 is inclined so as to gradually increase as it approaches the center of the protruding member 45. The shape of the inclined surface 45t2 is the same as the shape according to the first embodiment. Also according to this embodiment, the same operation and effect as the first embodiment are exhibited.

(Third embodiment)
The shape of the protruding member 451 according to the second embodiment viewed from the protruding direction is a square. On the other hand, the shape seen from the protruding direction of the protruding member 452 according to the present embodiment is a rhombus flattened in a direction extending toward the first inlet 53a and the second inlet 54a, as shown in FIG. . That is, it is a rhombus in which the corners facing the first inlet 53a and the second inlet 54a are acute angles and the remaining corners are obtuse. Also according to this embodiment, the same operation and effect as the first embodiment are exhibited.

(Fourth embodiment)
The shape of the protruding member 451 according to the second embodiment viewed from the protruding direction is a quadrangle. On the other hand, the shape seen from the protruding direction of the protruding member 453 according to the present embodiment is circular as shown in FIG. Also according to this embodiment, the same operation and effect as the first embodiment are exhibited.

(Fifth embodiment)
The shape seen from the protruding direction of the protruding member 453 according to the fourth embodiment is a perfect circle. On the other hand, the shape seen from the protruding direction of the protruding member 454 according to the present embodiment is an elliptical shape as shown in FIG. That is, it is a circular shape that is flat in a direction extending toward the first inlet 53a and the second inlet 54a. Also according to this embodiment, the same operation and effect as the first embodiment are exhibited.

(Sixth embodiment)
In the first embodiment, the first circulation part 53 and the second circulation part 54 communicate with the vortex generating part 55a, and urea water flows from the two circulation parts into the vortex generating part 55a. On the other hand, in this embodiment, as shown in FIG. 14, urea water flows into the vortex generating part 55a from three circulation parts. Specifically, the nozzle hole member 50 according to the present embodiment includes a third circulation part 59 in addition to the first circulation part 53 and the second circulation part 54. These three flow passages are arranged at equal intervals in the circumferential direction. According to this embodiment, urea water flows into the vortex generator 55a from the three flow passages to form a vortex component.

(Seventh embodiment)
In this embodiment shown in FIG. 15, the circular protruding member 453 according to the sixth embodiment is changed to a polygonal protruding member 455. According to this embodiment, vortex generation is further promoted compared to the sixth embodiment.

(Other embodiments)
The reducing agent injection valve described in the claims is not limited to the embodiment described above, and can be implemented with various modifications as exemplified below. Not only combinations of parts that clearly show that combinations are possible in each embodiment, but also combinations of the embodiments even if they are not explicitly stated unless there is a problem with the combination. Is also possible.

  In the said 1st Embodiment, the 1st through-hole 43 and the 2nd through-hole 44 have 1st channel | path 43b, 43c and 2nd channel | path 44b, 44c. On the other hand, the first through hole 43P and the second through hole 44P as shown in FIG. 7, that is, a through hole in which the first passages 43b and 43c and the second passages 44b and 44c are eliminated may be used.

  In the first embodiment, the merging portion 55 has a shape in which the width dimension L5 of the first flow portion 53 and the width dimension L5 of the second flow portion 53 are widened as viewed from the protruding direction of the protruding member 45. The width L5 may be reduced. For example, the diameter D2 of the vortex generator 55a may be larger or smaller than the width dimension L5 of the first circulation part 53 and the second circulation part.

  In the said 1st Embodiment, although the width dimension L6 of the protrusion member 45 seen from the protrusion direction of the protrusion member 45 is large compared with the width dimension L5 of the 1st inflow port 53a and the 2nd inflow port 54a, these width dimensions. It may be smaller than L5.

  In the first embodiment, the protruding end surface 45a of the protruding member 45 is located closer to the injection hole than the first inflow port 53a and the second inflow port 54a, but may be located closer to the counter injection hole.

  The projecting member 45 according to the first embodiment includes the first inclined surface 45t1 and the second inclined surface 45t2 that are inclined in the direction in which the width dimension is gradually increased. However, these inclined surfaces may be eliminated.

  In the first embodiment, the first flow part 53 and the second flow part 54 are arranged on the same plane and have a shape extending perpendicular to the central axis C. On the other hand, the first flow part 53 and the second flow part 54 extend in a direction inclined with respect to a plane perpendicular to the central axis C in a cross-sectional view including the central axis C (see FIG. 4). Also good. For example, the first flow part 53 and the second flow part 54 may have a shape extending in a direction inclined with respect to a plane perpendicular to the central axis C.

  In each of the above embodiments, the diameter D2 of the merging portion 55 is set smaller than the flow path length of the second flow portion 54 or the merging portion 55, but may be set larger than these flow path lengths.

  In each of the above embodiments, the first through hole 43 and the second through hole 44 have the same shape, and the first flow part 53 and the second flow part 54 have the same shape, but may have different shapes. Further, instead of arranging them symmetrically with respect to the central axis C, they may be arranged asymmetrically.

  In each said embodiment, the number of the nozzle holes 51 formed in the nozzle member 50 is one. On the other hand, a plurality of injection holes 51 may be formed in the injection hole member 50. For example, a plurality of nozzle holes may be branched from one merging portion 55 so that urea water in the merging portion 55 is distributed to the plurality of nozzle holes.

  In each said embodiment, although the 1st through-hole 43 (1st flow-path part) and the 2nd through-hole 44 (2nd flow-path part) are isolate | separated without communicating directly, these through-holes 43, 44 may communicate with the plate member 40. For example, one end of the first passage 43 b of the first through hole 43 and one end of the second passage 44 b of the second through hole 44 may communicate with each other.

  In each of the above embodiments, among the channel lengths of the first through holes 43, the channel length on one end side from the first communication portion 43a and the channel length on the other end side from the first communication portion 43a are the same. These channel lengths may be different. Similarly, among the channel lengths of the second through hole 44, the channel length on one end side from the second communication portion 44a and the channel length on the other end side from the second communication portion 44a may be the same. It may be good or different.

  In each of the above embodiments, the first through hole 43 (first flow path portion) and the second through hole 44 (second flow) are formed in the plate member 40 disposed adjacent to the body 31 and the injection hole member 50. Road part) is formed. On the other hand, the plate member 40 may be abolished and the through holes 43 and 44 may be formed in the body 31 or the injection hole member 50.

  In each of the above embodiments, the material of the plate member 40 is made of metal, but may be made of resin. Similarly, the material of the nozzle hole member 50 is not limited to being made of metal, and may be made of resin. The reducing agent injection valve according to each of the above embodiments injects urea water as a reducing agent, but may inject a liquid hydrocarbon compound as a reducing agent.

  DESCRIPTION OF SYMBOLS 30 ... Reducing agent injection valve, 30F ... Supply flow path, 32 ... Valve body, 45 ... Projection member, 45a ... Projection end surface, 45t1 ... 1st inclined surface, 45t2 ... 2nd inclined surface, 51 ... Injection hole, 53 ... 1st 1 circulation part, 54 ... 2nd circulation part, 55 ... confluence | merging part, 53a ... 1st inlet, 54a ... 2nd inlet.

Claims (8)

An internal combustion engine (10), comprising an injection hole (51) for injecting a reducing agent, a supply passage (30F) for supplying the reducing agent to the injection hole, and a valve body (32) for opening and closing the supply passage. A reducing agent injection valve for injecting a reducing agent to the upstream side of the purification device (20) in the exhaust passage (11a).
The supply channel is
A first flow part (53) and a second flow part (54) for flowing the reducing agent in different directions;
A merging section (55) for bringing together the reducing agent that has circulated through the first circulation section and the reducing agent that has circulated through the second circulation section, and leading the merged reducing agent to the nozzle hole;
Have
A reducing agent injection valve in which a projecting member (45) protruding toward the injection hole is arranged at the junction.   2. The reducing agent injection valve according to claim 1, wherein the joining part has a shape in which a width dimension of the first circulation part and a width dimension of the second circulation part are widened when viewed from the projecting direction of the protruding member. The inflow port that flows from the first flow part to the merging part is a first inflow port (53a), and the inflow port that flows from the second flow part to the merging part is a second inflow port (54a),
The width dimension of the said protrusion member seen from the protrusion direction of the said protrusion member is large compared with the width dimension of the said 1st inflow port seen from the said protrusion direction, and the width dimension of the said 2nd inflow port. The reducing agent injection valve described. The inflow port that flows from the first flow part to the merging part is a first inflow port (53a), and the inflow port that flows from the second flow part to the merging part is a second inflow port (54a),
The reducing agent injection valve according to any one of claims 1 to 3, wherein a protruding end surface (45a) of the protruding member is located closer to the nozzle hole than the first inlet and the second inlet. The inflow port that flows from the first flow part to the merging part is a first inflow port (53a), and the inflow port that flows from the second flow part to the merging part is a second inflow port (54a),
The protruding member is
A first inclined surface (45t1) that is inclined in a direction in which a width dimension seen from the protruding direction of the protruding member gradually increases from the first inlet toward the center of the protruding member;
A second inclined surface (45t2) that is inclined in a direction in which a width dimension seen from the protruding direction gradually increases from the second inlet toward the center of the protruding member;
The reducing agent injection valve according to any one of claims 1 to 4. The first circulation part and the second circulation part have a shape extending on the same plane,
The reducing agent injection valve according to claim 1, wherein the protruding member has a shape protruding perpendicularly to the plane. The supply channel is
A first flow path portion (43) for causing the reducing agent flowing from one end side to collide with the reducing agent flowing from the other end side, and guiding the reducing agent after the collision to the first flow portion;
A second flow path portion (44) for causing the reducing agent flowing from one end side to collide with the reducing agent flowing from the other end side, and leading the reducing agent after the collision to the second flow portion;
The reducing agent injection valve according to any one of claims 1 to 6. A portion of the first flow path portion that communicates with the first flow portion is referred to as a first communication portion (43a),
A portion of the second flow path portion that communicates with the second flow portion is referred to as a second communication portion (44a),
Of the channel length of the first channel portion, the channel length on one end side from the first communication portion and the channel length on the other end side from the first communication portion are the same,
8. The flow path length on one end side from the second communication section and the flow path length on the other end side from the second communication section are the same among the flow path lengths of the second flow path section. Reducing agent injection valve.

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