JP6733701B2 - Injector - Google Patents

Description

The present disclosure relates to injectors.

For example, Patent Document 1 discloses a fuel injection valve including a needle that opens and closes an injection hole, and a movable core that is provided separately from the needle valve. In this fuel injection valve, the needle valve moves in the valve opening direction together with the movable core that receives the magnetic attraction force from the fixed core. After the movable core contacts the fixed core, the needle valve separates from the movable core due to inertia, and further moves in the valve opening direction. After that, the needle valve is pushed back by the spring, moves in the valve closing direction, and again contacts the movable core.

JP, 2016-65545, A

In the above-mentioned fuel injection valve (injector), when the needle is pushed back by the spring and comes into contact with the movable core, a large impact force may be generated, and the contact portion between the needle and the movable core may be worn. Suppressing wear at the contact portion is an important issue regardless of whether the injector is a liquid fuel injector or a gaseous fuel injector. In particular, in the injector that injects the gaseous fuel, the squeeze force by the fuel that the contact portion receives when the needle and the movable core contact each other becomes smaller and the impact force becomes larger than that in the injector that injects the liquid fuel. The problem you have made becomes more prominent.

The present disclosure can be realized as the following modes.

According to one form of this indication, an injector (20, 20B, 20C, 20D, 20E) is provided. This injector has a cylindrical housing (30) having a nozzle hole (32) for injecting fuel and having a first flow path (101) communicating with the nozzle hole; fixed in the housing; A cylindrical fixed core (41) in which a second flow path (102) communicating with the first flow path is formed; and a shaft of the housing in the first flow path closer to the injection hole than the fixed core. A movable core (42) provided so as to be capable of reciprocating along the direction (AX), having an outer diameter larger than the inner diameter of the fixed core, and having a through hole (43) smaller than the inner diameter of the fixed core; A coil (44) for generating a magnetic field for moving the movable core toward the fixed core by energization; a shaft portion (51) passing through the through hole so as to reciprocate in the axial direction; A needle (50) formed at an end portion on the injection hole side and having a valve portion (52) capable of opening and closing the injection hole; and a spring (61) for urging the needle toward the injection hole side. And; The shaft portion has a first protruding portion (53) on the valve portion side and a second protruding portion (54) on the fixed core side with the movable core interposed therebetween; and the first protruding portion has a radial direction. And projecting outward from the edge of the through hole in the movable core ; the second projecting portion in the radial direction being outside the edge of the through hole in the movable core and within the fixed core. A first surface (531) which is a surface of the first protrusion on the fixed core side, and a second surface (541) which is a surface of the second protrusion on the valve portion side. A third surface (421), which is a surface of the movable core on the valve portion side, and a fourth surface (422), which is a surface of the movable core on the fixed core side, with respect to a distance along the axial direction. Has a smaller interval along the axial direction; an elastic member (55) is provided on at least one of the first surface and the third surface ; It has a notch (56) toward the outer peripheral side.

According to the injector of this aspect, since the first surface of the first protruding portion of the needle and the third surface of the movable core are in contact with each other via the elastic member, the impact when the first protruding portion and the movable core collide with each other. The force is reduced, and accordingly, the impact force when the second protrusion of the needle collides with the movable core is also reduced. Therefore, it is possible to suppress wear of the movable core, wear of the first protrusion contacting the movable core via the elastic member, and wear of the second protrusion contacting the movable core.

The present disclosure can be implemented in various forms other than the injector. For example, it can be realized in the form of a fuel injection device, a fuel injection method, or the like.

Explanatory drawing which shows schematic structure of the injector in 1st Embodiment. II-II sectional view taken on the line of the needle in 1st Embodiment. The 1st explanatory view showing the valve opening operation of the injector in a 1st embodiment. The 2nd explanatory view showing the valve opening operation of the injector in a 1st embodiment. The 3rd explanatory view showing the valve opening operation of the injector in a 1st embodiment. The 1st explanatory view showing the valve closing operation of the injector in a 1st embodiment. The 2nd explanatory view showing the valve closing operation of the injector in a 1st embodiment. The 3rd explanatory view showing the valve closing operation of the injector in a 1st embodiment. Explanatory drawing which shows schematic structure of the injector in 2nd Embodiment. Explanatory drawing which shows schematic structure of the injector in 3rd Embodiment. Explanatory drawing which shows schematic structure of the injector in 4th Embodiment. Explanatory drawing which shows schematic structure of the injector in 5th Embodiment. Explanatory drawing which shows the groove|channel provided in the movable core in other embodiment.

A. First embodiment:
As shown in FIG. 1, the injector 20 of the first embodiment includes a housing 30, a fixed core 41, a movable core 42, a coil 44, a needle 50, a first spring 61, a second spring 62, and And an elastic member 55. The injector 20 is a device for injecting fuel. The injector 20 of this embodiment injects hydrogen gas, which is a gaseous fuel, as fuel.

The housing 30 is a tubular member having an injection hole 32 for injecting fuel and a first flow path 101 communicating with the injection hole 32. The housing 30 of the present embodiment includes, in order from the injection hole 32 side, a nozzle tip portion 31 in which the injection hole 32 is formed, a first magnetic portion 34, a non-magnetic portion 36, a second magnetic portion 35, and an inlet portion. And 37. A valve seat 33 is provided around the injection hole 32 on the surface of the nozzle tip portion 31 inside the housing 30. Between the nozzle tip portion 31 and the first magnetic portion 34, between the first magnetic portion 34 and the non-magnetic portion 36, between the non-magnetic portion 36 and the second magnetic portion 35, the second magnetic portion 35 and the inlet portion. The welds 38 and 37 are welded to each other. In this embodiment, the nozzle tip portion 31 is made of martensitic stainless steel which is a non-magnetic material. The first magnetic portion 34 and the second magnetic portion 35 are formed of ferritic stainless steel which is a magnetic material. The non-magnetic portion 36 is formed of austenitic stainless steel which is a non-magnetic material.

A supply pipe (not shown) for supplying fuel to the injector 20 is connected to the inlet portion 37. The supply pipe is connected so as to come into contact with a backup ring 72 provided at the inlet portion 37. The O-ring 73 provided on the backup ring 72 seals between the supply pipe and the inlet 37. An inlet passage 103 is formed in the inlet portion 37. A filter 71 is provided in the inlet channel 103. The filter 71 collects foreign matter contained in the fuel supplied from the supply pipe and suppresses the foreign matter from flowing into the housing 30.

The fixed core 41 is a tubular member fixed in the housing 30. In the fixed core 41, a second channel 102 communicating with the first channel 101 is formed. The side of the second channel 102 opposite to the first channel 101 communicates with the inlet channel 103. In this embodiment, the fixed core 41 is made of ferritic stainless steel which is a magnetic material.

The movable core 42 is a tubular member provided so as to be capable of reciprocating along the axial direction AX of the housing 30 in the first flow path 101 on the injection hole 32 side with respect to the fixed core 41. The movable core 42 has an outer diameter larger than the inner diameter of the fixed core 41, and has a through hole 43 smaller than the inner diameter of the fixed core 41. The movable core 42 and the fixed core 41 are configured to be contactable in the axial direction AX. In this embodiment, the movable core 42 is formed of ferritic stainless steel which is a magnetic material.

The coil 44 is wound around the outer periphery of the housing 30. The outer circumference of the coil 44 is covered with a yoke 45 made of a ferritic stainless steel which is a magnetic material. The coil 44 generates a magnetic field that moves the movable core 42 toward the fixed core 41 side when energized. The current flowing through the coil 44 is supplied from a power supply source (not shown) such as a battery. The voltage applied from the power supply source is controlled by the controller (not shown).

The needle 50 includes a shaft portion 51, a valve portion 52, a stopper portion 53, and a flange portion 54. In addition, in this specification, the stopper portion 53 may be referred to as a first protruding portion, and the flange portion 54 may be referred to as a second protruding portion. The shaft portion 51 is provided so as to be capable of reciprocating in the through hole 43 of the movable core 42 along the axial direction AX. The central axis of the shaft portion 51 is the same as the central axis of the fixed core 41 and the central axis of the movable core 42. A communication passage 104 is formed inside the shaft portion 51 so that fuel flows from the second passage 102 toward the first passage 101.

The valve portion 52 is formed at the end portion of the shaft portion 51 on the injection hole 32 side. The valve portion 52 is configured to be in contact with the valve seat 33 provided on the nozzle tip portion 31, and is a valve body that opens and closes the injection hole 32 by reciprocating movement of the shaft portion 51 along the axial direction AX. .. The fuel that has flowed through the housing 30 in the order of the inlet flow passage 103, the second flow passage 102, the communication flow passage 104, and the first flow passage 101 is injected from the injection hole 32 by opening the injection hole 32. ..

The stopper portion 53 is a disk-shaped member located closer to the valve portion 52 than the movable core 42 of the shaft portion 51. The stopper portion 53 projects more than the diameter of the through hole 43 in the radial direction of the shaft portion 51. The stopper portion 53 has a first surface 531 on the fixed core 41 side. In the present embodiment, the stopper portion 53 is made of austenitic stainless steel, which is a non-magnetic material, and is press-fitted into the shaft portion 51.

The flange portion 54 is a disk-shaped member located closer to the fixed core 41 than the movable core 42 of the shaft portion 51. The flange portion 54 protrudes in the radial direction of the shaft portion 51 larger than the diameter of the through hole 43 and smaller than the inner diameter of the fixed core 41. The flange portion 54 has a second surface 541 on the valve portion 52 side. The distance between the first surface 531 of the stopper portion 53 and the second surface 541 of the flange portion 54 along the axial direction AX is the axial direction AX between the third surface 421 of the movable core 42 and the fourth surface 422 of the movable core 42. Greater than the spacing along. In other words, the thickness of the movable core 42 is smaller than the distance between the first surface 531 of the stopper portion 53 and the second surface 541 of the flange portion 54 along the axial direction AX. In this embodiment, the shaft portion 51, the valve portion 52, and the flange portion 54 are integrally formed. The shaft portion 51, the valve portion 52, and the flange portion 54 are formed of martensitic stainless steel which is a non-magnetic material.

The first spring 61 is arranged in the second flow path 102. The first spring 61 urges the flange portion 54 from the fixed core 41 side toward the injection hole 32 side. In this embodiment, the first spring 61 is a coil spring. An adjusting pipe 63 is provided on the upstream side of the first spring 61 in the second flow path 102. The force with which the first spring 61 pushes the flange portion 54 is configured to be adjustable by adjusting the position of the end portion of the adjusting pipe 63 on the injection hole 32 side.

The second spring 62 is disposed in the first flow path 101 and biases the movable core 42 from the injection hole 32 side toward the fixed core 41 side. The second spring 62 of the present embodiment is a coil spring. In the valve closed state, the movable core 42 is pushed by the second spring 62, and the second surface 541 of the flange portion 54 and the fourth surface 422 of the movable core 42 come into contact with each other.

In the present embodiment, the elastic member 55 is provided on the first surface 531 of the stopper portion 53. The elastic member 55 of this embodiment is rubber. As the rubber, for example, fluororubber or silicone rubber can be used. The elastic member 55 is bonded to the first surface 531 by vulcanization bonding, for example.

As shown in FIG. 2, the elastic member 55 is provided with a cutout portion 56 extending from the inner peripheral side to the outer peripheral side of the elastic member 55. In the present embodiment, the notch 56 is formed by adhering the elastic member 55 so that a part of the outer peripheral portion of the stopper 53 is exposed. The cutout portion 56 of the present embodiment extends linearly from the inner peripheral side to the outer peripheral side of the elastic member 55. The cutout portion 56 may have any shape as long as foreign matter is easily discharged from the inner peripheral side of the elastic member 55 toward the outer peripheral side thereof. A part of the outer peripheral portion of the stopper portion 53 is not exposed, and a groove extending from the inner peripheral side to the outer peripheral side of the elastic member 55 is formed on the elastic member 55, so that the cutout portion 56 is formed. Good.

The valve opening operation performed in the injector 20 of the present embodiment will be described with reference to FIGS. 1 and 3 to 5. As shown in FIG. 1, in the valve closed state, the valve portion 52 is in contact with the valve seat 33. In the valve closed state, the coil 44 is not energized. The flange portion 54 is pushed by the first spring 61 from the fixed core 41 side toward the injection hole 32 side. The movable core 42 is pushed by the second spring 62 from the injection hole 32 side toward the fixed core 41 side. Therefore, the second surface 541 of the flange portion 54 and the fourth surface 422 of the movable core 42 are in contact with each other. A predetermined space required for opening the valve is secured between the movable core 42 and the fixed core 41 in the valve closed state. In this specification, this state is also called an initial state.

As shown in FIG. 3, when the coil 44 is energized, the magnetic attraction force from the fixed core 41 acts on the movable core 42, and the movable core 42 moves from the injection hole 32 side toward the fixed core 41 side. The movable core 42 collides with the fixed core 41 by moving the movable core 42. This magnetic attraction force is generated by the magnetic field formed around the fixed core 41 as the coil 44 is energized. In the initial state, since the second surface 541 of the flange portion 54 and the fourth surface 422 of the movable core 42 are in contact with each other, when the movable core 42 moves from the injection hole 32 side toward the fixed core 41 side, the flange The second surface 541 of the portion 54 is pushed by the fourth surface 422 of the movable core 42, and the needle 50 moves together with the movable core 42. Therefore, the valve portion 52 separates from the valve seat 33, and the fuel injection from the injection hole 32 is started. As the needle 50 moves, the first spring 61 is pushed by the flange portion 54 and contracts, so that elastic energy is stored in the first spring 61.

As shown in FIG. 4, after the movable core 42 collides with the fixed core 41, the needle 50 separates from the movable core 42 due to inertia, and further moves toward the upstream side of the second flow path 102. The first surface 531 of the stopper portion 53 collides with the third surface 421 via the elastic member 55. The impact force due to the collision between the first surface 531 of the stopper portion 53 and the third surface 421 of the movable core 42 is absorbed by the elastic member 55. Therefore, the impact force when the first surface 531 of the stopper portion 53 and the third surface 421 of the movable core 42 collide with each other is reduced. The impact force due to the collision between the movable core 42 and the fixed core 41 is reduced by the needle 50 being separated from the movable core 42.

As shown in FIG. 5, after the first surface 531 of the stopper portion 53 and the third surface 421 of the movable core 42 collide with each other, the elastic energy stored in the first spring 61 is released as power for pushing back the needle 50. Accordingly, the needle 50 moves from the fixed core 41 side toward the injection hole 32 side, and the second surface 541 of the flange portion 54 again collides with the fourth surface 422 of the movable core 42. As the impact force when the first surface 531 of the stopper portion 53 and the third surface 421 of the movable core 42 collide is reduced by the elastic member 55, the rebound of the needle 50 is suppressed and the flange portion 54 The impact force when the second surface 541 and the fourth surface 422 of the movable core 42 collide again is reduced. After that, the second surface 541 of the flange portion 54 is supported by the fourth surface 422 of the movable core 42, so that the lift amount between the valve portion 52 and the valve seat 33 is secured. The valve opening operation of the injector 20 is completed by the series of operations described above.

The valve closing operation performed in the injector 20 of the present embodiment will be described with reference to FIGS. 6 to 8. As shown in FIG. 6, when the coil 44 is de-energized, the magnetic attraction force from the fixed core 41 acting on the movable core 42 is unloaded, and the needle urged by the first spring 61 is urged. The valve portion 52 collides with the valve seat 33 by moving 50 from the fixed core 41 side toward the injection hole 32 side. Therefore, the valve is closed, and the fuel injection from the injection hole 32 is stopped. When the needle 50 moves, the fourth surface 422 of the movable core 42 is pushed by the second surface 541 of the flange portion 54, so that the movable core 42 moves with the needle 50.

As shown in FIG. 7, after the valve portion 52 collides with the valve seat 33, the movable core 42 continues to move further from the fixed core 41 side toward the injection hole 32 side by inertia, so that the movable core 42 moves. The third surface 421 collides with the first surface 531 of the stopper portion 53 via the elastic member 55. The impact force due to the collision between the third surface 421 of the movable core 42 and the first surface 531 of the stopper portion 53 is absorbed by the elastic member 55. Therefore, the impact force when the first surface 531 of the stopper portion 53 and the third surface 421 of the movable core 42 collide with each other is reduced. The impact force caused by the collision between the valve portion 52 and the valve seat 33 is reduced by the movable core 42 continuing to move separately from the needle 50.

As shown in FIG. 8, the movable core 42 moves from the injection hole 32 side toward the fixed core 41 side by the impact force when the first surface 531 of the stopper portion 53 and the third surface 421 of the movable core 42 collide. The second surface 541 of the flange portion 54 and the fourth surface 422 of the movable core 42 collide with each other by bouncing back. As the impact force when the first surface 531 of the stopper portion 53 and the third surface 421 of the movable core 42 collide is reduced by the elastic member 55, the rebound of the movable core 42 is suppressed and the flange portion The impact force when the second surface 541 of 54 and the fourth surface 422 of the movable core 42 collide is reduced. Then, the movable core 42 is supported by the second spring 62 and returns to the initial state. The valve closing operation of the injector 20 is completed by the series of operations described above.

According to the injector 20 of the present embodiment described above, the first surface 531 of the stopper portion 53 and the third surface 421 of the movable core 42 come into contact with each other via the elastic member 55, and thus the first surface of the stopper portion 53. The impact force when 531 and the third surface 421 of the movable core 42 collide is reduced, and accordingly, the impact when the second surface 541 of the flange portion 54 and the fourth surface 422 of the movable core 42 collide. Power is also reduced. Therefore, it is possible to suppress wear of the movable core 42, wear of the first protruding portion 53 that contacts the movable core 42 via the elastic member 55, and wear of the second protruding portion 54 that contacts the movable core 42. In particular, when the injector 20 is in the form of injecting gaseous fuel as in the present embodiment, compared to the form of injecting liquid fuel, the first surface 531 of the stopper portion 53 and the third surface 421 of the movable core 42, Also, since the squeeze force due to the fuel when the second surface 541 of the flange portion 54 and the fourth surface 422 of the movable core 42 collide is small, the impact force becomes large. Therefore, the elastic member 55 has a great effect of suppressing wear of the movable core 42, the first protruding portion 53, and the second protruding portion 54.

Further, in the present embodiment, since rubber is used as the elastic member 55, wear of the movable core 42, the first protruding portion 53, and the second protruding portion 54 can be suppressed with a simple structure.

In addition, in the present embodiment, since the elastic member 55 is provided with the cutout portion 56, the dischargeability of foreign matter from the elastic member 55 is improved, and for example, the foreign matter passes through the filter 71 and is mixed into the flow path. Even if foreign matter or foreign matter generated due to wear of the flange portion 54 and the movable core 42 passes through the gap between the through hole 43 of the movable core 42 and the shaft portion 51 of the needle 50 and flows onto the elastic member 55, The first surface 531 of the stopper portion 53 and the third surface 421 of the movable core 42 are suppressed from colliding with each other with foreign matter interposed. Therefore, wear of the movable core 42 and the first protruding portion 53 is further suppressed.

B. Second embodiment:
As shown in FIG. 9, in the injector 20B of the second embodiment, the elastic member 55 is provided not on the first surface 531 of the stopper portion 53 but on the third surface 421 of the movable core 42 according to the first embodiment. Different from Other configurations and opening/closing operations are the same as those in the first embodiment.

Also in the injector 20B of this aspect, the first surface 531 of the stopper portion 53 and the third surface 421 of the movable core 42 contact each other via the elastic member 55, so that the first surface 531 of the stopper portion 53 and the movable core 42 are in contact with each other. The impact force when the third surface 421 collides is reduced, and accordingly, the impact force when the second surface 541 of the flange portion 54 and the fourth surface 422 of the movable core 42 collide is also reduced.

C. Third embodiment:
As shown in FIG. 10, in the injector 20C of the third embodiment, the elastic member 55 is provided on both the first surface 531 of the stopper portion 53 and the third surface 421 of the movable core 42 as the first embodiment. Different from the form. Other configurations and opening/closing operations are the same as those in the first embodiment.

According to the injector 20C of this aspect, since the elastic member 55 is provided on both the first surface 531 of the stopper portion 53 and the third surface 421 of the movable core 42, the injector 20C is movable with the first surface 531 of the stopper portion 53. The impact force when the third surface 421 of the core 42 collides is further reduced, and accordingly, the impact force when the second surface 541 of the flange portion 54 and the fourth surface 422 of the movable core 42 collide is further reduced. Will be reduced.

D. Fourth Embodiment:
As shown in FIG. 11, the injector 20D of the fourth embodiment is different from that of the first embodiment in that an elastic member 55 is also provided on the second surface 541 of the flange portion 54. Other configurations and opening/closing operations are the same as those in the first embodiment. The elastic member 55 may be provided on the fourth surface 422 of the movable core 42 instead of the second surface 541 of the flange portion 54, or the second surface 541 of the flange portion 54 and the fourth surface 422 of the movable core 42. The elastic member 55 may be provided on both of these.

According to the injector 20D of this aspect, since the second surface 541 of the flange portion 54 and the fourth surface 422 of the movable core 42 are in contact with each other via the elastic member 55, the second surface 541 of the flange portion 54 and the movable core 42 are in contact with each other. The impact force when colliding with the fourth surface 422 of 42 is further reduced.

E. Fifth embodiment:
As shown in FIG. 12, the injector 20E of the fifth embodiment differs from that of the first embodiment in that liquid fuel is injected as fuel. Further, the nozzle tip portion 31E is provided with a plurality of injection holes 32, which is different from the first embodiment. Other configurations and opening/closing operations are the same as those in the first embodiment. The liquid fuel is, for example, gasoline or light oil.

According to the injector 20E of this aspect, since the liquid fuel is injected, the first surface 531 of the stopper portion 53 and the third surface 421 of the movable core 42 collide with each other as compared with the case of injecting the gaseous fuel. At this time, and when the second surface 541 of the flange portion 54 and the fourth surface 422 of the movable core 42 collide with each other, the squeeze force due to the fuel increases and the impact force is reduced.

F. Other embodiments:
(F-1) In the injector 20 according to each of the above-described embodiments, the elastic member 55 is provided with the cutout portion 56. On the other hand, the elastic member 55 may not be provided with the cutout portion 56. In this case, the contact area of the elastic member 55 is larger than that in the case where the cutout portion 56 is provided. Therefore, the impact force when the first surface 531 of the stopper portion 53 and the third surface 421 of the movable core 42 collide is further reduced, and accordingly, the second surface 541 of the flange portion 54 and the first surface of the movable core 42 are reduced. The impact force when colliding with the four surfaces 422 is further reduced.

(F-2) In the injector 20 according to each of the above-described embodiments, the cutout portion 56 is provided in the elastic member 55 provided on the first surface 531 of the stopper portion 53. On the other hand, as shown in FIG. 13, of the first surface 531 of the stopper portion 53 and the third surface 421 of the movable core 42, the third surface 421 of the movable core 42 in which the elastic member 55 is not provided. However, it may have a groove 57 extending from the inner peripheral side to the outer peripheral side of the movable core 42. The groove 57 has a form that extends linearly from the inner peripheral side to the outer peripheral side of the movable core 42. The groove 57 may have any shape as long as foreign matter is easily discharged from the inner peripheral side to the outer peripheral side of the movable core 42. Further, when the injector 20 is in the form in which the elastic member 55 is provided on the third surface 421 of the movable core 42, the first surface 531 of the stopper portion 53 where the elastic member 55 is not provided is the stopper portion 53. You may have the groove which goes to the outer peripheral side from the inner peripheral side. Even in these cases, it is possible to prevent the first surface 531 of the stopper portion 53 and the third surface 421 of the movable core 42 from colliding with each other with foreign matter interposed.

(F-3) In the injector 20 in each of the above-described embodiments, rubber is used as the elastic member 55. On the other hand, the elastic member 55 may be an elastic body other than rubber. For example, it may be a thermoplastic elastomer or the like. The elastic member 55 may be any elastic body that can reduce the impact force.

The present disclosure is not limited to the above-described embodiments, and can be realized with various configurations without departing from the spirit thereof. For example, the technical features in the embodiments may be appropriately replaced or combined in order to solve some or all of the above problems or to achieve some or all of the above effects. Is possible. If the technical features are not described as essential in this specification, they can be deleted as appropriate.

20, 20B, 20C, 20D, 20E injector, 30 housing, 31, 31E nozzle tip part, 32 injection hole, 33 valve seat, 34 first magnetic part, 35 second magnetic part, 36 non-magnetic part, 37 inlet part, 38 welded part, 41 fixed core, 42 movable core, 43 through hole, 44 coil, 45 yoke, 50 needle, 51 shaft part, 52 valve part, 53 stopper part, 54 flange part, 55 elastic member, 56 notch part, 57 grooves, 61 first spring, 62 second spring, 63 adjusting pipe, 71 filter, 72 backup ring, 73 O-ring, 101 first flow path, 102 second flow path, 103 inlet flow path, 104 communication flow path , 421 third surface, 422 fourth surface, 531 first surface, 541 second surface, AX axis direction.

Claims (5)

Injectors (20, 20B, 20C, 20D, 20E),
A tubular housing (30) having an injection hole (32) for injecting fuel, and having a first flow path (101) communicating with the injection hole;
A tubular fixed core (41) fixed in the housing and having a second flow path (102) formed therein, the second flow path (102) communicating with the first flow path;
The first flow path on the injection hole side of the fixed core is provided so as to be capable of reciprocating along the axial direction (AX) of the housing, and has an outer diameter larger than the inner diameter of the fixed core. A movable core (42) having a through hole (43) smaller than the inner diameter of the fixed core;
A coil (44) that generates a magnetic field that moves the movable core toward the fixed core by energization;
A shaft portion (51) passing through the through hole so as to reciprocate in the axial direction; and a valve portion (52) formed at an end portion of the shaft portion on the injection hole side and capable of opening and closing the injection hole. A needle (50) having
A spring (61) for urging the needle toward the injection hole side;
Equipped with
The shaft portion has a first protruding portion (53) on the valve portion side and a second protruding portion (54) on the fixed core side with the movable core interposed therebetween.
The first protruding portion protrudes radially outward from an edge of the through hole in the movable core ,
The second projecting portion projects in the radial direction outside an edge of the through hole in the movable core and inside an inner peripheral edge of the fixed core ,
Along the axial direction, a first surface (531) that is a surface of the first protrusion on the fixed core side and a second surface (541) that is a surface of the second protrusion on the valve portion side. Along the axial direction, a third surface (421), which is the surface of the movable core on the valve portion side, and a fourth surface (422), which is the surface of the movable core on the fixed core side, are arranged with respect to the axial direction. The spacing is smaller,
An elastic member (55) is provided on at least one of the first surface and the third surface ,
The elastic member has a cutout portion (56) extending from the inner peripheral side toward the outer peripheral side,
Injector. The injector according to claim 1, wherein
The injector, wherein the elastic member is rubber. The injector according to claim 1 or claim 2 ,
The elastic member is provided on any one of the first surface and the third surface,
An injector having a groove (57) extending from an inner peripheral side toward an outer peripheral side on a surface of the first surface and the third surface where the elastic member is not provided. The injector according to any one of claims 1 to 3 , wherein:
An injector in which an elastic member (55) is provided on at least one of the second surface and the fourth surface. The injector according to any one of claims 1 to 4 , wherein:
An injector that injects gas as the fuel.

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