JP6961998B2 - Reducing agent injection valve - Google Patents

Description

The disclosure herein relates to a reducing agent injection valve that injects a reducing agent.

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

Japanese Unexamined Patent Publication No. 2014-238016

By the way, in recent years, it has become desired to arrange the purification device 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 that case, the spray from the injection valve is wide-angled so that the urea water is uniformly sprayed on the exhaust inflow surface of the purification device. Is required.

One object disclosed is to provide a reducing agent injection valve with a wide angle of spraying of the reducing agent.

The reducing agent injection valve disclosed here includes a injection hole (51) for injecting a reducing agent, a supply flow path (30F) for supplying the reducing agent to the injection hole, and a valve body (32) for opening and closing the supply flow path. A reducing agent injection valve that injects a reducing agent onto the upstream side of the purification device (20) in the exhaust passage (11a) of the internal combustion engine (10).
The supply channels are the first distribution section (53) and the second distribution section (54) that distribute the reducing agents in different directions, and the reducing agent that flows through the first distribution section and the reducing agent that flows through the second distribution section. Has a merging portion (55), which merges with and guides the merging reducing agent to the injection hole.
A protrusion member (45) protruding toward the injection hole is arranged at the confluence .
The first flow section and the second flow section are reducing agent injection valves extending in the radial direction from the confluence portion extending along the central axis (C) of the valve body toward opposite sides via the central axis.
The disclosed reducing agent injection valve includes a injection hole (51) for injecting a reducing agent, a supply flow path (30F) for supplying the reducing agent to the injection hole, and a valve body (32) for opening and closing the supply flow path. A reducing agent injection valve that injects 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 channel is
The first distribution section (53) and the second distribution section (54), which distribute the reducing agents in different directions,
A confluence section (55) that merges the reducing agent that has flowed through the first distribution section and the reducing agent that has flowed through the second distribution section, and guides the merged reducing agent to the injection hole.
A first flow path portion (43) that collides the reducing agent that has flowed in from one end side with the reducing agent that has flowed in from the other end side and guides the reducing agent after the collision to the first distribution unit.
A second flow path portion (44) that collides the reducing agent that has flowed in from one end side with the reducing agent that has flowed in from the other end side and guides the reducing agent after the collision to the second distribution section.
Have,
A reducing agent injection valve in which a protrusion member (45) projecting toward the injection hole is arranged at the merging portion.

According to the reducing agent injection valve disclosed here, when the reducing agents distributed in different directions merge, the mainstreams of the reducing agents merge after colliding with the protruding member, and the reducing agents of each other merge. It is suppressed that they collide head-on and merge. Then, the reducing agent that collides with the protrusion member flows in a direction away from the protrusion member when viewed from the protrusion direction of the protrusion member, swirls, and is urged to join thereafter. As a result, the reducing agent after merging is ejected from the injection hole while swirling so as to spread away from the center line of the injection hole, so that the spraying of the reducing agent can be widened.

The disclosed aspects herein employ different technical means to achieve their respective objectives. The claims and the reference numerals in parentheses described in this section exemplify the correspondence with the parts of the embodiments described later, and are not intended to limit the technical scope. The objectives, features, and effects disclosed herein will be made clearer by reference to the subsequent detailed description and accompanying drawings.

The schematic diagram which shows the state which the reducing agent injection valve which concerns on 1st Embodiment is attached to an exhaust pipe. The figure which shows the simple substance state of the reducing agent injection valve shown in FIG. FIG. 2 is a cross-sectional view of the reducing agent injection valve shown in FIG. Enlarged view of FIG. The exploded perspective view of FIG. FIG. 5 is a view taken along the line VI of FIG. The figure which shows the reducing agent injection valve which concerns on 1st comparative example of 1st Embodiment. VIII arrow view of FIG. 4, schematically showing a first distribution section, a second distribution section, a confluence section, and a protrusion member in the first embodiment. The figure which shows the reducing agent injection valve which concerns on 2nd comparative example of 1st Embodiment. In the second embodiment, a schematic view of a first distribution section, a second distribution section, a confluence section, and a protrusion member as viewed from the injection hole side. FIG. 3 is a schematic view of a first distribution section, a second distribution section, a confluence section, and a protrusion member as viewed from the injection hole side in the third embodiment. FIG. 4 is a schematic view of a first distribution section, a second distribution section, a confluence section, and a protrusion member as viewed from the injection hole side in the fourth embodiment. FIG. 5 is a schematic view of a first distribution section, a second distribution section, a confluence section, and a protrusion member as viewed from the injection hole side in the fifth embodiment. FIG. 6 is a schematic view of a first distribution section, a second distribution section, a confluence section, and a protrusion member as viewed from the injection hole side in the sixth embodiment. FIG. 7 is a schematic view of a first distribution section, a second distribution section, a confluence section, and a protrusion member as viewed from the injection hole side in the seventh embodiment.

Hereinafter, a plurality of embodiments will be described with reference to the drawings. In each form, the same reference numerals may be given to the parts corresponding to the matters described in the preceding forms, and duplicate explanations may be omitted. In each form, when only a part of the configuration is described, the other parts of the configuration can be applied with reference to the other forms described above.

(First Embodiment)
The internal combustion engine 10 shown in FIG. 1 is mounted on a vehicle and functions as a traveling drive source. The exhaust gas discharged from the combustion chamber of the internal combustion engine 10 flows through the exhaust passage 11a inside the exhaust pipe 11, is purified by the purification device 20 or the like, and then is discharged to the atmosphere. The purification device 20 has a function of reducing and purifying NOx (nitrogen oxide) contained in the 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 housed inside the passage member 21 to purify the exhaust gas, and a catalyst layer supported by the base material 22.

The base material 22 is made of ceramic formed in a honeycomb shape, and the outer shape of the base material 22 is a cylindrical shape extending in the exhaust flow direction. Of both end faces of the cylinder of the base material 22, the end faces on the upstream side of the exhaust flow function as the exhaust inflow port 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 gas, and for example, platinum is used. Zeolite is used as the adsorbing component, and it physically adsorbs ammonia, which will be described later.

A reducing agent injection valve 30 for injecting a reducing agent is attached to the upstream portion 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 the 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 on the catalyst layer. Specifically, ammonia is physically adsorbed on the adsorbed component contained in the catalyst layer.

A part of the adsorbed ammonia reduces NOx contained in the exhaust gas on the reducing catalyst component contained in the catalyst layer. Therefore, strictly speaking, it cannot be said to be a reducing agent in the state of urea water injected from the reducing agent injection valve 30, and ammonia produced by hydrolysis of the urea water acts as a reducing agent. However, in the present embodiment, urea water, which 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 inside. When the valve body 32 is opened by the electromagnetic attraction generated by energizing the electric actuator 33, urea water is injected into the exhaust passage 11a from the injection hole 51 (see FIG. 3) formed in the body 31.

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

The vehicle is equipped with a tank 30T for storing urea water and a pump 30P for pumping 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 by extension, the injection pressure of the urea water from the injection hole 51 is controlled.

An electronic control device (hereinafter referred to as ECU) (not shown) controls the start and stop of injection of urea water from the injection hole 51 by controlling the energization of the electric actuator 33. Further, the ECU controls the injection pressure of urea water by controlling the power supplied to the electric motor of the pump 30P. The reducing agent injection system according to the present embodiment includes an ECU and a reducing agent injection valve 30. The exhaust gas 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 has an electromagnetic coil 331, a fixed core 332, and a movable core 333. When the electromagnetic coil 331 is energized, 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 due to the magnetic flux. Since the movable core 333 is attached to the valve body 32, the valve body 32 reciprocates together with the movable core 333 in the central axis C direction.

The body 31 of the reducing agent injection valve 30 has a base end side body 311, a non-magnetic member 312, a tip end side body 313, a magnetic member 314, a plate member 40, and a jet hole member 50. The base end side body 311 has a cylindrical shape that holds a fixed core 332 inside. The non-magnetic member 312 is arranged between the base end side body 311 and the tip end side body 313, and blocks the above-mentioned magnetic flux. The tip side body 313 has a cylindrical shape that houses the valve body 32 inside. A seat surface 313s on which the seat surface 32s provided at the tip of the valve body 32 is detached and seated is formed on the inner peripheral surface of the cylinder of the tip side 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 311a of the base end side body 311, the internal passage 332a of the fixed core 332, the internal passage 333a of the movable core 333, and the internal passage 32a of the valve body 32. It will be distributed in order. After that, the urea water in the internal passage 32a flows out from the outlet 32b (see FIG. 2) and the outlet 32c (FIG. 3 and) formed on the side wall of the valve body 32. Then, the annular passage 313a formed between the inner peripheral surface of the tip side body 313 and the outer peripheral surface of the valve body 32 and the merging passage 313b along the tip of the valve body 32 are sequentially circulated. The annular aisle 313a is opened and closed when the valve body 32 is taken off and seated on the seat surface 313s. In the merging passage 313b, urea water distributed in a ring shape in the annular passage 313a is merged and distributed in a disk shape including the central axis C. The central axis of the annular passage 313a, the merging passage 313b, and the injection hole 51 coincides with the central axis C of the valve body 32.

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

The plate member 40 has a disk-shaped plate 41 that covers the confluence passage 313b 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 tip side body 313. The plate 41 is formed with a first through hole 43 and a second through hole 44 that communicate with the merging passage 313b. The first through hole 43 and the second through hole 44 are formed in a state of being separated from each other in the plate 41 without communicating with each other.

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 hole 43 and the second through hole 44 are the same as the radial positions of the outer peripheral edges of the merging passage 313b. The surface of the plate 41 on the anti-injection hole side has a flat shape extending perpendicular to the central axis C. A protrusion 45 that projects 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 protrusion member 45 may be manufactured by pressing the plate 41, cutting it, or welding it to the plate 41.

The injection hole member 50 is formed with one injection hole 51 for injecting urea water. The injection hole 51 has a shape extending in the central axis C direction along the central axis C of the injection hole member 50, and has a shape in which the passage cross-sectional area becomes larger toward the downstream side (see FIG. 5). The downstream end opening 51b of the injection hole 51 has a circular shape centered on the central axis C. An annular groove 52 surrounding the downstream end opening 51b is formed on the end surface of the injection hole member 50 on the side opposite to the plate member 40. By forming the annular groove 52, it is possible to prevent urea water from adhering to the peripheral portion of the downstream end opening 51b of the end surface of the injection hole member 50 due to surface tension.

On the surface of the injection hole member 50 that contacts the plate 41, a first distribution section 53 and a second flow section 54 that extend in different directions to flow urea water are formed. These distribution portions have a groove shape that opens toward the plate 41, and the groove opening is covered by the plate 41. The first distribution unit 53 and the second distribution unit 54 are arranged so as to extend on the same plane, extend linearly in the radial direction, and extend in parallel with each other.

Further, on the surface of the injection hole member 50 that contacts the plate 41, the urea water that has flowed through the first distribution section 53 and the urea water that has flowed through the second distribution section 54 are merged at the center of the injection hole member 50. A merging portion 55 is formed to guide the merging urea water to the injection hole 51. The merging portion 55 has a vortex generation portion 55a and a vortex outflow portion 55b (see FIG. 4).

The vortex generation portion 55a has a cylindrical shape extending in the central axis C direction. The vortex generation unit 55a communicates with the downstream end of the first distribution unit 53 and the downstream end of the second distribution unit 54. In the following description, the inflow port flowing from the first distribution section 53 into the vortex generation section 55a is the first inflow port 53a, and the inflow port flowing from the second distribution section 54 into the vortex generation section 55a is the second inflow port 54a. Called.

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

The protrusion member 45 formed on the plate 41 is arranged in the vortex generation portion 55a. The protrusion member 45 has a shape that protrudes perpendicularly to the surface of the plate 41, that is, a shape that protrudes in the central axis C direction (see FIGS. 3 and 4). The shape of the protrusion member 45 as seen from the injection hole side is a quadrangle having four vertices (see FIG. 8). The protrusion member 45 is arranged at a position facing the first inflow port 53a and the second inflow port 54a. The protrusion member 45 has a size that covers the first inflow port 53a when viewed from the flow direction of the first distribution section 53, and the area of the protrusion member 45 projected in the flow direction is larger than the area of the first inflow port 53a. big. The protrusion member 45 has a size that covers the second inflow port 54a when viewed from the flow direction of the second distribution section 54, and the area of the protrusion member 45 projected in the flow direction is larger than the area of the first inflow port 53a. big.

The protrusion length L1 of the protrusion member 45 is longer than the depth dimension L2 of the first flow section 53 and the depth dimension L2 of the second flow section 54 in the opening / closing operation direction (central axis C direction) of the valve body 32 (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 distribution section 53 and the depth dimension L2 of the second distribution section 54 are the same. Further, the protruding length L1 of the protruding member 45 is shorter than the depth dimension L3 of the merging portion 55 (see FIG. 4).

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

The vortex generation portion 55a has a shape in which the width dimension L5 of the first distribution portion 53 and the width dimension L5 of the second distribution portion 54 are widened when viewed from the protrusion direction of the protrusion member 45. That is, the diameter D2 of the vortex generation portion 55a is larger than the width dimension L5 (see FIGS. 6 and 8). The width dimension L5 of the first distribution section 53 and the width dimension L5 of the second distribution section 54 are the same.

The width dimension L6 of the protrusion member 45 (see FIG. 8), that is, the dimension in the vertical direction on the paper surface of FIG. 4, is the width dimension L5 of the first inflow port 53a and the width of the second inflow port 54a as seen from the protrusion direction of the protrusion member 45. It is larger than the 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 in a direction in which the width dimension of the protruding member 45 as seen from the protruding direction is gradually expanded from the first inflow port 53a toward the center of the protruding member 45. The second inclined surface 45t2 has a shape that is inclined in a direction in which the width dimension of the protruding member 45 as seen from the protruding direction is gradually expanded 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 a shape curved in a direction recessed toward the center side of the protrusion 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. 5 to 9. In the following description, the portion of the first through hole 43 that communicates with the first communication section 53 is referred to as the first communication section 43a, and the portion of the second through hole 44 that communicates with the second communication section 54 is the second. It is called the communication unit 44a. The portion of the first through hole 43 on one end side and the other end side of the first communication portion 43a are referred to as first passages 43b and 43c, and one end side of the second through hole 44 with respect to the second communication portion 44a. The portion and the portion on the other end side are referred to as the second passages 44b and 44c, respectively. The first communication portion 43a is arranged in the central portion of the first through hole 43, and the passage lengths of the two first passages 43b and 43c are the same. Similarly, the second communication portion 44a is arranged 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 merged from the annular passage 313a to the merging passage 313b flows into the first through hole 43 and the second through hole 44. Specifically, the urea water located directly above the first through hole 43 and the second through hole 44 in the merging passage 313b flows into the first through hole 43 and the second through hole 44 as it is. As shown by the arrow F1 in FIG. 5, the urea water at a position deviated from 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. Then, urea water flowing from one end side of both ends of the arc of the first through hole 43 toward the first communication portion 43a (see arrow F2) and urea water flowing from the other end side toward the first communication portion 43a (arrow F3). (See) collides head-on with the first communication portion 43a. That is, the urea water flowing through the two first passages 43b and 43c collide with each other at the first communication portion 43a. After that, the collided urea water flows into the radial outer ends of both ends of the first flow unit 53.

Similarly, the urea water flowing from one end side of both ends of the arc of the second through hole 44 toward the second communication portion 44a and the urea water flowing from the other end side toward the second communication portion 44a are in the second communication. Collision at part 44a. That is, the urea water flowing through the two second passages 44b and 44c respectively collide head-on at the second communication portion 44a. After that, the collided urea water flows into the radial outer ends of both ends of the second flow unit 54.

The urea water that has flowed into each of the first distribution section 53 and the second distribution section 54 flows toward the vortex generation section 55a of the confluence section 55. Then, the urea water (see arrow F4) that flows through the first flow section 53 and flows into the vortex generation section 55a from the first inflow port 53a and the vortex generation section 55a that flows through the second flow section 54 and flows from the second inflow port 54a to the vortex generation section 55a. The urea water (see arrow F5) that has flowed into the vortex generating portion 55a collides with the urea water.

Strictly speaking, the mainstream of these urea waters first collides with the protrusion member 45 in the vortex generation portion 55a, and flows in a swirling manner along the first inclined surface 45t1 and the second inclined surface 45t2 (arrow F6). , See F7). Then, the urea water that collides with the first inclined surface 45t1 and swirls (see arrow F6) and the urea water that collides with the second inclined surface 45t2 and swirls (see arrow F7) collide with each other at the vortex generation portion 55a and merge. do.

The urea water swirling in this way circulates in order to the vortex outflow portion 55b and the injection hole 51 while trying to increase the diameter of the vortex, that is, to expand radially outward, and then expands radially outward. It is ejected from the downstream end opening 51b while trying to squeeze. Therefore, even immediately after the injection is performed from the downstream end opening 51b, the spray F tends to spread outward in the radial direction, so that the angle of the spray F becomes large.

The internal passages 311a, 332a, 333a, 32a, the annular passage 313a, the merging passage 313b, the first through hole 43, the second through hole 44, the first distribution section 53, the second distribution section 54, and the merging section 55 are sprayed. It corresponds to the supply flow path 30F for supplying the reducing agent to the hole 51. Further, the first through hole 43 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 first flow section 53. 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 distribution section 54. do.

Based on the above, according to the present embodiment, the supply flow path 30F for supplying urea water to the injection hole 51 has the first distribution section 53 and the second distribution section 54 that circulate the urea water in different directions from each other, and the confluence section 55. And have. The merging section 55 merges the urea water that has flowed through the first distribution section 53 with the urea water that has flowed through the second distribution section 54, and guides the merged urea water to the injection hole 51. A protrusion 45 that projects toward the injection hole 51 is arranged at the merging portion 55.

Therefore, when the urea waters flowing in different directions merge with each other, the urea waters with each other collide with the protrusion member 45 and then merge with each other, so that the urea waters with each other collide head-on and merge with each other. Then, as shown by arrows F6 and F7 in FIG. 8, the urea water that has collided with the protrusion member 45 flows outward in the radial direction of the vortex generation portion 55a when viewed from the protrusion direction of the protrusion member 45, swirls, and then merges. You will be prompted to do so. As a result, the urea water after merging is ejected from the injection hole 51 while swirling in the direction of spreading in the radial direction, and the spray F can be wide-angled.

In the second comparative example shown in FIG. 9, the protrusion member 45 according to the present embodiment is abolished. In this case, the vortex component due to the collision with the protrusion member 45 as shown by the arrows F6 and F7 in FIG. 8 is not generated. Therefore, according to the present embodiment including the protrusion member 45, the spray F has a wider angle than the second comparative example in which the protrusion member 45 is abolished.

Further, in the present embodiment, the vortex generation portion 55a of the merging portion 55 has a shape in which the width dimension L5 of the first distribution portion 53 and the width dimension L5 of the second distribution portion 54 are widened when viewed from the protrusion direction of the protrusion member 45. Is. Therefore, the space required for the urea water to swirl can be sufficiently secured in the vortex generation unit 55a, the vortex generation of the urea water can be promoted, and the spray F can be promoted to spread in the radial direction.

Further, in the present embodiment, the width dimension L6 of the protrusion member 45 is larger than the width dimension L5 of the first inflow port 53a and the width dimension L5 of the second inflow port 54a seen from the protrusion direction of the protrusion member 45. According to this, it is possible to prevent a head-on collision between the mainstream of urea water flowing from the first inflow port 53a into the vortex generation section 55a and the mainstream of urea water flowing from the second inflow port 54a into the vortex generation section 55a. .. Therefore, the inhibition of spiral generation due to a head-on collision can be suppressed, and the spray F can be promoted to spread in the radial direction.

Further, in the present embodiment, the protruding end surface 45a of the protrusion member 45 is located closer to the injection hole 51 than the first inflow port 53a and the second inflow port 54a. Therefore, of the urea water flowing into the vortex generation section 55a from the first inflow port 53a and the second inflow port 54a, a component that flows into the vortex outflow section 55b without colliding with the protrusion member 45, that is, sufficient vortex generation is performed. The amount of components flowing into the vortex outflow portion 55b without being prevented can be reduced. Therefore, the formation of vortices of urea water can be promoted, and by extension, the spray F can be promoted to spread in the radial direction.

Further, in the present embodiment, the protrusion member 45 has a first inclined surface 45t1 and a second inclined surface 45t2. The first inclined surface 45t1 has a shape in which the width dimension L6 seen from the protruding direction of the protruding member 45 is gradually expanded from the first inflow port 53a toward the center of the protruding member 45. The second inclined surface 45t2 has a shape in which the width dimension L6 seen from the protruding direction of the protruding member 45 is gradually expanded from the second inflow port 54a toward the center of the protruding member 45.

Therefore, the urea water that flows from the first inflow port 53a into the vortex generation portion 55a and collides with the first inclined surface 45t1 flows along the first inclined surface 45t1, so that the direction of the flow is bent outward in the radial direction. Is promoted to swirl. Similarly, the urea water that flows from the second inflow port 54a into the vortex generation portion 55a and collides with the second inclined surface 45t2 flows along the second inclined surface 45t2, so that the direction of the flow is outward in the radial direction. It is promoted to be bent and swirled. Therefore, the formation of vortices of urea water can be promoted, and by extension, the spray F can be promoted to spread in the radial direction.

Further, in the present embodiment, the first inclined surface 45t1 and the second inclined surface 45t2 have a shape curved in a direction recessed toward the center side of the protrusion member 45. Therefore, the urea water flowing along the first inclined surface 45t1 and the second inclined surface 45t2 is promoted 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 distribution unit 53 and the second distribution unit 54 are arranged on the same plane, that is, on a plane perpendicular to the central axis C, and the protrusion member 45 is arranged in the distribution direction of the first distribution unit 53 and the first. 2 The shape is such that it projects perpendicularly to the distribution direction of the distribution unit 54. Therefore, the inflow direction from the first inflow port 53a into the vortex generation section 55a and the inflow direction from the second inflow port 54a into the vortex generation section 55a are on the same plane, that is, on a plane perpendicular to the central axis C. Is placed in. Therefore, it is promoted that the swirl of the urea water flowing in from the first inflow port 53a and the swirl of the urea water flowing in from the second inflow port 54a are located on the same plane. Therefore, it is promoted that the urea water after merging is ejected from the injection hole 51 while swirling in the direction of spreading in the radial direction, and the widening of the spray F can be promoted.

Further, the present embodiment includes a first through hole 43 for communicating the merging passage 313b and the first distribution section 53, and a second through hole 44 for communicating the merging passage 313b and the second distribution section 54. The first through hole 43 has a first communication portion 43a and two first passages 43b and 43c. The first communication unit 43a communicates with the downstream ends of the two first passages 43b and 43c, and also communicates with the first distribution unit 53. The two first passages 43b and 43c circulate urea water in different directions to guide the urea water to the first communication portion 43a and cause the two passages 43b and 43c to collide with each other. The second communication section 44a communicates with the downstream ends of the two second passages 44b and 44c and also communicates with the second distribution section 54. The two second passages 44b and 44c circulate urea water in different directions to guide the urea water to the second communication portion 44a and cause the two passages 44b and 44c to collide with each other.

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 confluence portion 55. Therefore, the urea water flowing through the first distribution unit 53 and the second distribution unit 54 can be brought into a state containing a large number of vortex components, that is, a state having high turbulent energy. As a result, the vortex generation of urea water in the vortex generation unit 55a can be promoted, and by extension, the spray F can be promoted to spread in the radial direction. The above-mentioned turbulent energy can be said to be the sum of the kinetic energies 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 the first through hole 43P and the second through hole 44b in which the first passage 43b and 43c are abolished. The 44c is replaced with the abolished second through hole 44P. In this case, the urea water distributed in the merging passage 313b flows evenly from around the first through hole 43 and the second through hole 44, so that the urea water collides with the first through hole 43 and the second through hole 44. Rarely 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. At 44, urea water is urged to collide.

Further, in the present embodiment, the passage lengths of the two first passages 43b and 43c are made the same by arranging the first communication portion 43a in the central portion of the first through hole 43. In other words, of the flow path lengths of the first through hole 43 (first flow path portion), the flow path length on one end side of the first communication portion 43a and the flow path length on the other end side of the first communication portion 43a are It is the same. Therefore, the collision position of the urea water can be set to the first communication portion 43a, and the urea water immediately after the collision can be promoted to flow into the first distribution portion 53.

Similarly, by arranging the second communication portion 44a in the central 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 flow path lengths of the second through hole 44 (second flow path portion), the flow path length on one end side of the second communication portion 44a and the flow path length on the other end side of the second communication portion 44a are It is the same. Therefore, the collision position of the urea water can be set to the second communication portion 44a, and the urea water immediately after the collision can be promoted to flow into the second distribution portion 54.

(Second Embodiment)
In the protrusion member 45 according to the first embodiment, the first inclined surface 45t1 and the second inclined surface 45t2 have a shape curved in a direction recessed toward the center side of the protrusion member 45. On the other hand, in the protrusion 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. The first inclined surface 45t1 and the second inclined surface 45t1 according to the present embodiment are in that the width dimension seen from the protruding direction of the protruding member 45 is inclined in a direction of gradually expanding 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. This embodiment also exerts the same actions and effects as those of the first embodiment.

(Third Embodiment)
The shape of the protrusion member 451 according to the second embodiment as seen from the protrusion direction is square. On the other hand, the shape of the protrusion member 452 according to the present embodiment as seen from the protrusion direction is a rhombus flattened in a direction extending toward the first inflow port 53a and the second inflow port 54a, as shown in FIG. .. That is, it is a rhombus in which the corners facing the first inflow port 53a and the second inflow port 54a are acute angles and the remaining corners are obtuse angles. This embodiment also exerts the same actions and effects as those of the first embodiment.

(Fourth Embodiment)
The shape of the protrusion member 451 according to the second embodiment as seen from the protrusion direction is a quadrangle. On the other hand, the shape of the protrusion member 453 according to the present embodiment as seen from the protrusion direction is circular as shown in FIG. This embodiment also exerts the same actions and effects as those of the first embodiment.

(Fifth Embodiment)
The shape of the protrusion member 453 according to the fourth embodiment as seen from the protrusion direction is a perfect circle. On the other hand, the shape of the protrusion member 454 according to the present embodiment as seen from the protrusion direction is an elliptical shape as shown in FIG. That is, it is a circular shape flattened in a direction extending toward the first inflow port 53a and the second inflow port 54a. This embodiment also exerts the same actions and effects as those of the first embodiment.

(Sixth Embodiment)
In the first embodiment, the first distribution unit 53 and the second distribution unit 54 communicate with the vortex generation unit 55a, and urea water flows into the vortex generation unit 55a from the two distribution units. On the other hand, in the present embodiment, as shown in FIG. 14, urea water flows into the vortex generation section 55a from the three distribution sections. Specifically, the injection hole member 50 according to the present embodiment has a third distribution unit 59 in addition to the first distribution unit 53 and the second distribution unit 54. These three flow passages are arranged at equal intervals in the circumferential direction. According to the present embodiment, urea water flows into the vortex generation portion 55a from the three flow passages to form a vortex component.

(7th Embodiment)
In the present embodiment shown in FIG. 15, the circular protrusion member 453 according to the sixth embodiment is changed to the polygonal protrusion member 455. According to the present embodiment, vortex generation is further promoted as compared with the sixth embodiment.

(Other embodiments)
The reducing agent injection valve described in the claims can be implemented in various modifications as illustrated below without being limited to the above-described embodiment. Not only the combination of the parts that clearly indicate that the combination is possible in each embodiment, but also the partial combination of the embodiments even if the combination is not specified if there is no problem in the combination. Is also possible.

In the first embodiment, the first through hole 43 and the second through hole 44 have the first passages 43b and 43c and the second passages 44b and 44c. On the other hand, the first through hole 43P and the second through hole 44P as shown in FIG. 7, that is, the through holes in which the first passages 43b and 43c and the second passages 44b and 44c are abolished may be used.

In the first embodiment, the merging portion 55 has a shape in which the width dimension L5 of the first distribution portion 53 and the width dimension L5 of the second distribution portion are widened when viewed from the protrusion direction of the protrusion member 45. The width dimension L5 of the above may be reduced. For example, the diameter D2 of the vortex generation unit 55a may be larger or smaller than the width dimension L5 of the first distribution unit 53 and the second distribution unit.

In the first embodiment, the width dimension L6 of the protrusion member 45 when viewed from the protrusion direction of the protrusion member 45 is larger than the width dimension L5 of the first inflow port 53a and the second inflow port 54a, but these width dimensions It may be smaller than L5.

In the first embodiment, the protruding end surface 45a of the protrusion member 45 is located on the injection hole side with respect to the first inflow port 53a and the second inflow port 54a, but may be located on the anti-injection hole side.

The protrusion member 45 according to the first embodiment has a first inclined surface 45t1 and a second inclined surface 45t2 that are inclined in a direction in which the width dimension is gradually increased, but these inclined surfaces may be abolished.

In the first embodiment, the first distribution unit 53 and the second distribution unit 54 are arranged on the same plane and have a shape extending perpendicular to the central axis C. On the other hand, the first distribution unit 53 and the second distribution unit 54 have a shape extending 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). May be good. For example, the first distribution unit 53 and the second distribution unit 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 to be smaller than the flow path length of the second distribution section 54 or the merging section 55, but may be set to be 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 distribution unit 53 and the second distribution unit 54 have the same shape, but they may have different shapes. Further, instead of arranging them symmetrically with respect to the central axis C, they may be arranged asymmetrically.

In each of the above embodiments, the number of injection holes 51 formed in the injection hole 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 injection holes may be branched from one merging portion 55 so that the urea water in the merging portion 55 is distributed to the plurality of injection holes.

In each of the above embodiments, the first through hole 43 (first flow path portion) and the second through hole 44 (second flow path portion) are separated without direct communication, but these through holes 43, 44 may communicate with the plate member 40. For example, one end of the first passage 43b of the first through hole 43 and one end of the second passage 44b of the second through hole 44 may communicate with each other.

In each of the above embodiments, among the flow path lengths of the first through hole 43, the flow path length on one end side of the first communication portion 43a and the flow path length on the other end side of the first communication portion 43a are the same. , These flow path lengths may be different. Similarly, of the flow path lengths of the second communication hole 44, even if the flow path length on one end side of the second communication portion 44a and the flow path length on the other end side of the second communication portion 44a are the same. It may or may not be 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 arranged 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 metal, but it may be made of resin. Similarly, the material of the injection hole member 50 is not limited to metal, but may be 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.

30 ... Reducing agent injection valve, 30F ... Supply flow path, 32 ... Valve body, 45 ... Protruding member, 45a ... Protruding end surface, 45t1 ... First inclined surface, 45t2 ... Second inclined surface, 51 ... Injection hole, 53 ... No. 1 distribution section, 54 ... second distribution section, 55 ... confluence section, 53a ... first inflow port, 54a ... second inflow port.

Claims (9)

An internal combustion engine (10) including a injection hole (51) for injecting a reducing agent, a supply flow path (30F) for supplying the reducing agent to the injection hole, and a valve body (32) for opening and closing the supply flow path. ), Which is a reducing agent injection valve that injects the reducing agent to the upstream side of the purification device (20) in the exhaust passage (11a).
The supply flow path is
The first distribution section (53) and the second distribution section (54), which distribute the reducing agents in different directions,
A confluence section (55) that merges the reducing agent that has flowed through the first distribution section and the reducing agent that has flowed through the second distribution section, and guides the merged reducing agent to the injection hole.
Have,
A protrusion member (45) projecting toward the injection hole is arranged at the merging portion .
The first flow section and the second flow section are reducing agents extending in the radial direction from the confluence portion extending along the central axis (C) of the valve body toward opposite sides via the central axis. Injection valve. The supply flow path is
A first flow path portion (43) that collides the reducing agent that has flowed in from one end side with the reducing agent that has flowed in from the other end side and guides the reducing agent after the collision to the first distribution unit.
A second flow path portion (44) that collides the reducing agent that has flowed in from one end side with the reducing agent that has flowed in from the other end side and guides the reducing agent after the collision to the second distribution unit.
The reducing agent injection valve according to claim 1. An internal combustion engine (10) including a injection hole (51) for injecting a reducing agent, a supply flow path (30F) for supplying the reducing agent to the injection hole, and a valve body (32) for opening and closing the supply flow path. ), Which is a reducing agent injection valve that injects the reducing agent to the upstream side of the purification device (20) in the exhaust passage (11a).
The supply flow path is
The first distribution section (53) and the second distribution section (54), which distribute the reducing agents in different directions,
A confluence section (55) that merges the reducing agent that has flowed through the first distribution section and the reducing agent that has flowed through the second distribution section, and guides the merged reducing agent to the injection hole.
A first flow path portion (43) that collides the reducing agent that has flowed in from one end side with the reducing agent that has flowed in from the other end side and guides the reducing agent after the collision to the first distribution unit.
A second flow path portion (44) that collides the reducing agent that has flowed in from one end side with the reducing agent that has flowed in from the other end side and guides the reducing agent after the collision to the second distribution unit.
Have,
A reducing agent injection valve in which a protruding member (45) projecting toward the injection hole is arranged at the merging portion. The portion of the first flow path portion that communicates with the first communication portion is referred to as a first communication portion (43a).
The portion of the second flow path portion that communicates with the second communication portion is referred to as a second communication portion (44a).
Of the flow path lengths of the first communication portion, the flow path length on one end side of the first communication portion and the flow path length on the other end side of the first communication portion are the same.
Of the flow path length of the second flow passage portion, to claim 2 or 3 wherein the second communicating unit flow path length of one side of a flow path length of the other end side of the second communicating portion are identical The reducing agent injection valve described. The merging portion has a shape obtained by widening the width dimension of the first flow section and the width dimension of the second flow section when viewed from the projecting direction of the protrusion member, according to any one of claims 1 to 4. The reducing agent injection valve described. The inflow port flowing from the first distribution section to the confluence section is referred to as the first inflow port (53a), and the inflow port flowing from the second distribution section to the confluence section is referred to as the second inflow port (54a).
The width dimension of the protrusion member seen from the protrusion direction of the protrusion member is larger than the width dimension of the first inflow port and the width dimension of the second inflow port seen from the protrusion direction, according to claims 1 to 5. The reducing agent injection valve according to any one. The inflow port flowing from the first distribution section to the confluence section is referred to as the first inflow port (53a), and the inflow port flowing from the second distribution section to the confluence section is referred to as the second inflow port (54a).
The reducing agent injection valve according to any one of claims 1 to 6 , wherein the protruding end surface (45a) of the protruding member is located closer to the injection hole than the first inflow port and the second inflow port. The inflow port flowing from the first distribution section to the confluence section is referred to as the first inflow port (53a), and the inflow port flowing from the second distribution section to the confluence section is referred to as the second inflow port (54a).
The protrusion member
A first inclined surface (45t1) that is inclined in a direction in which the width dimension seen from the protruding direction of the protruding member gradually expands as it approaches the center of the protruding member from the first inflow port.
A second inclined surface (45t2) that inclines in a direction in which the width dimension seen from the protruding direction gradually expands as it approaches the center of the protruding member from the second inflow port.
The reducing agent injection valve according to any one of claims 1 to 7. The first distribution section and the second distribution section have a shape extending on the same plane.
The reducing agent injection valve according to any one of claims 1 to 8 , wherein the protruding member has a shape that protrudes perpendicularly to the plane.

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