JP4683035B2 - Injector - Google Patents

Description

  The present invention relates to an injector that injects fuel into an internal combustion engine.

  2. Description of the Related Art An injector having a cylindrical body that has a nozzle hole at its tip and supports a nozzle having a needle for controlling opening and closing of the nozzle hole at its end is known (see Patent Document 1). The injector body has a high-pressure passage for supplying high-pressure fuel to the nozzle, a low-pressure passage for discharging excess fuel that has not been injected by the nozzle, and a housing hole for housing a driving means for controlling the opening and closing operation of the needle. It is formed in the direction.

The inlet side opening of the high pressure passage is formed at the end of the body. The opening on the outlet side of the low-pressure passage and the opening of the accommodation hole for taking out a lead wire or the like for supplying power to the driving means are formed on the outer peripheral wall of the body.
JP 2006-233853 A

  Various pipes, electrical wirings, and the like are attached to an internal combustion engine (hereinafter referred to as an engine) to which an injector is attached. As described above, the injector is connected to at least the high-pressure fuel pipe connected to the high-pressure passage, the electric wiring for supplying power to the driving means, and the low-pressure fuel pipe connected to the low-pressure passage. In addition to the pipes and electrical wiring connected to the injectors described above, various pipes, electrical wirings, and auxiliary machines are attached to an internal combustion engine (hereinafter referred to as an engine) to which the injector is attached. Under these circumstances, the arrangement of pipes and electrical wiring connected to the injector may be limited by the arrangement of other pipes and electrical wiring.

  For this reason, depending on the pipe and electrical wiring attached to the engine, the injector main body may be attached to the engine, but the low pressure fuel pipe may not be attached to the low pressure passage of the injector.

  About this, it is thought that it can respond by changing the formation position of the exit side opening part of a low pressure passage. However, since the high-pressure passage and the accommodation hole are formed in the body in addition to the low-pressure passage as described above, the range of the formation position of the outlet side opening of the low-pressure passage is limited. When the low-pressure fuel pipe is arranged outside the range where the outlet opening can be formed, a body suitable for the arrangement of the pipe must be prepared, and it is very difficult to share the injector body. It was.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide an injector that can be attached to various types of engines.

According to the first aspect of the present invention, there is provided a nozzle having a nozzle hole at the tip and a needle for controlling opening and closing of the nozzle hole inside, a cylindrical shape, supporting the nozzle at the end, A high-pressure passage for supplying fuel to the nozzle, a low-pressure passage for discharging surplus fuel not injected by the nozzle to the low-pressure side, and a housing hole for housing a driving means for controlling the opening / closing operation of the needle extend in the axial direction. A body having a low-pressure passage opening formed on an outer peripheral wall, and an injector comprising:
By covering the outer peripheral wall of the body, a fuel passage is formed between the inner peripheral wall and the outer peripheral wall so as to communicate with the opening and distribute excess fuel discharged from the opening in the circumferential direction. The connector further includes a passage member having an extraction portion communicating with the connector, and is formed of resin at an end opposite to the side where the body nozzle is attached, and supports a wire for supplying power to the driving means. And the passage member is embedded in the resin forming the connector .

According to this configuration, by attaching the passage member to the outer peripheral wall of the body, the excess fuel discharged from the opening in the circumferential direction is communicated with the opening of the low-pressure passage between the inner peripheral wall and the outer peripheral wall. A fuel passage for circulation is formed. The passage member is formed with an extraction portion communicating with the fuel passage. According to this, the circumferential direction position of the extraction part can be set to an arbitrary place only by changing the attachment position of the passage member. That is, the degree of freedom of the circumferential position of the extraction portion can be increased as compared with the conventional injector. As a result, it is possible to attach to various types of engines without changing the arrangement of the high-pressure passage, the low-pressure passage and the accommodation hole formed in the body. In addition, since the passage member is embedded in the resin forming the connector that supports the electric wire that supplies power to the driving means, the passage member can be fixed to the body simultaneously with the molding of the connector.

  The invention according to claim 2 of the present invention is characterized in that a passage groove portion extending in the circumferential direction is formed on the inner peripheral wall of the passage member or the outer peripheral wall facing the inner peripheral wall of the passage member of the body. . According to this configuration, a groove-shaped passage groove portion having a simple structure is provided on either the inner peripheral wall of the passage member or the outer peripheral wall of the body, and the passage groove portion is attached to the body so as to communicate with the opening of the low-pressure passage. Only by this, the fuel passage can be easily formed.

  The invention described in claim 3 of the present invention is characterized in that a seal member surrounding the fuel passage is provided between the inner peripheral wall of the passage member and the outer peripheral wall of the body. According to this configuration, since the seal member that surrounds the fuel passage is provided between the inner peripheral wall of the passage member and the outer peripheral wall of the body, it is possible to prevent the fuel from leaking from the gap between the passage member and the body. . Since the sealing member is provided, fuel leakage can be prevented even if a slight gap is generated between the inner peripheral wall of the passage member and the outer peripheral wall of the body, so that the manufacturing cost is increased by increasing the processing accuracy of the passage member. Can be suppressed.

  The invention according to claim 4 of the present invention is characterized in that the seal member is fitted into a seal groove formed in the inner peripheral wall of the passage member or the outer peripheral wall of the body. According to this configuration, it is possible to prevent the seal member from shifting from a predetermined position when the passage member is fitted into the outer peripheral wall of the body.

According to a sixth aspect of the present invention, there is provided a nozzle having a nozzle hole at the tip and a needle for controlling the opening and closing of the nozzle hole inside, a cylindrical shape, supporting the nozzle at the end, A high-pressure passage for supplying fuel to the nozzle, a low-pressure passage for discharging surplus fuel not injected by the nozzle to the low-pressure side, and a housing hole for housing a driving means for controlling the opening / closing operation of the needle extend in the axial direction. A body having a low-pressure passage opening formed on an outer peripheral wall, and an injector comprising:
By covering the outer peripheral wall of the body, a fuel passage is formed between the inner peripheral wall and the outer peripheral wall so as to communicate with the opening and distribute excess fuel discharged from the opening in the circumferential direction. A passage member having a take-out portion communicating with the outer peripheral wall of the body is provided with a projecting portion projecting in a radial direction, and one end portion of the inner peripheral wall of the passage member opens at an axial end surface of the passage member. However, the groove portion is formed such that the convex portion can be inserted through the opening, and the groove portion becomes narrower as the convex portion is inserted from one end portion toward the other end portion.

According to this configuration, by attaching the passage member to the outer peripheral wall of the body, the excess fuel discharged from the opening in the circumferential direction is communicated with the opening of the low-pressure passage between the inner peripheral wall and the outer peripheral wall. A fuel passage for circulation is formed. The passage member is formed with an extraction portion communicating with the fuel passage. According to this, the circumferential direction position of the extraction part can be set to an arbitrary place only by changing the attachment position of the passage member. That is, the degree of freedom of the circumferential position of the extraction portion can be increased as compared with the conventional injector. As a result, it is possible to attach to various types of engines without changing the arrangement of the high-pressure passage, the low-pressure passage and the accommodation hole formed in the body. Further, by inserting a convex portion protruding from the outer peripheral wall of the body into the groove formed on the inner peripheral wall of the passage member, the passage member can be attached to a predetermined position on the outer peripheral wall of the body. Further, since the groove width of the groove portion becomes narrower toward the other end portion, the convex portion can be press-fitted into the groove portion, and the passage member can be firmly fixed to the outer peripheral wall of the body.

According to a seventh aspect of the present invention, the inner peripheral wall of the passage member or the inner periphery of the body passage member is provided.
The outer peripheral wall facing the wall is formed with a passage groove portion extending in the circumferential direction.
The According to this configuration, the structure is provided on either the inner peripheral wall of the passage member or the outer peripheral wall of the body.
A simple groove-shaped passage groove is provided on the body so that the passage groove communicates with the opening of the low-pressure passage.
A fuel passage can be easily formed only by attaching.

The invention according to claim 8 of the present invention is characterized in that a seal member surrounding the fuel passage is provided between the inner peripheral wall of the passage member and the outer peripheral wall of the body. According to this configuration, since the seal member that surrounds the fuel passage is provided between the inner peripheral wall of the passage member and the outer peripheral wall of the body, it is possible to prevent the fuel from leaking from the gap between the passage member and the body. . Since the sealing member is provided, fuel leakage can be prevented even if a slight gap is generated between the inner peripheral wall of the passage member and the outer peripheral wall of the body, so that the manufacturing cost is increased by increasing the processing accuracy of the passage member. Can be suppressed.

The invention according to claim 9 of the present invention is characterized in that the seal member is fitted in a seal groove formed in the inner peripheral wall of the passage member or the outer peripheral wall of the body. According to this configuration, it is possible to prevent the seal member from shifting from a predetermined position when the passage member is fitted into the outer peripheral wall of the body.

The invention according to claim 10 of the present invention is characterized in that the passage member is embedded in a resin provided on the outer peripheral wall of the body. According to this configuration, the passage member can be firmly fixed to the body.

According to an eleventh aspect of the present invention, the groove portion is connected to the axial groove portion having one end portion extending in the axial direction of the passage member and having a groove width larger than the width of the convex portion, and the axial groove portion. It is characterized by comprising a circumferential groove that extends in the circumferential direction of the passage member and narrows toward the other end. According to this configuration, after the passage member is attached to the body, the passage member can be reliably prevented from moving in the axial direction.

According to a twelfth aspect of the present invention, the passage member is fitted in a recess formed in the outer peripheral wall of the body. According to this configuration, since the passage member is fitted in the recess formed in the outer peripheral wall of the body, an increase in the outer diameter of the injector when the passage member is fixed to the body can be suppressed as much as possible.

According to a thirteenth aspect of the present invention, there is provided a connector for supporting an electric wire that is formed of resin at the end opposite to the side where the body nozzle is attached and supplies power to the driving means. The passage member is embedded in a resin different from the resin forming the connector.
When the connector is formed of resin, at least the body and the electric wire are fixed at predetermined positions in the mold, and then the molten resin is poured into the mold. On the other hand, when the passage member is embedded in the resin, similarly, at least the body and the passage member are fixed at predetermined positions in the mold, and then the molten resin is poured into the mold. If the process of forming the connector and the process of fixing the passage member are performed at the same time, the number of members (body, electric wire, passage member) to be fixed in the molding die increases, and on the contrary, the work efficiency decreases and the manufacturing cost increases. There is a fear.
According to this configuration, the number of members to be fixed in the mold can be reduced by separately forming the connector and fixing the passage member, thereby suppressing a decrease in work efficiency and increasing the manufacturing cost. Can be suppressed.

  Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
A cross section of an injector according to a first embodiment of the present invention is shown in FIG. The injector 10 is used, for example, in a common rail fuel injection device for a diesel engine, and injects high pressure fuel supplied from a common rail (not shown) into a combustion chamber of the engine. 2 is an enlarged cross-sectional view of a main part of the injector 10, and FIG. 3 is a cross-sectional view taken along line III-III in FIG.

  The injector 10 includes a nozzle 20, an orifice plate 40, a valve body 50, a control valve 60, a lower body 70, a piezo actuator 90, a driving force transmission unit 93, and the like. The injector 10 is laminated in the order of the nozzle 20, the orifice plate 40, the valve body 50, and the lower body 70 from below in the figure, and is fixed to each other by a retaining nut 110.

  The nozzle 20 includes a nozzle body 21, a needle 30, a coil spring 36, a cylinder 37, and the like. A nozzle hole 22 is formed in the nozzle body 21 from the upper end portion to the vicinity of the lower end portion. By disposing the orifice plate 40 at the upper end of the nozzle body 21, the nozzle hole 22 becomes a closed space.

  A plurality of nozzle holes 23 through which the nozzle hole 22 and the outer wall of the nozzle body 21 pass are formed at the tip of the nozzle body 21. In the nozzle hole 22, a valve seat 24 is formed on the upstream side of the opening of the injection hole 23. A guide portion 25 that supports the needle 30 so as to be slidable in the axial direction is formed on the side wall of the nozzle hole 22. In the nozzle hole 22, a needle 30, a coil spring 36, and a cylinder 37 are accommodated.

  The needle 30 is formed in a rod shape. A valve body portion 31 that controls the opening and closing of the nozzle hole 23 by being attached to and detached from the valve seat 24 is formed at the tip thereof. A cylinder sliding portion 32 is formed at the end of the needle 30 opposite to the valve body portion 31. The cylinder sliding portion 32 is a sliding portion that is slidably supported in the axial direction on an inner peripheral wall 38 of a cylinder 37 formed in a substantially cylindrical shape that is accommodated in the nozzle hole 22.

  A body sliding portion 33 is formed between the valve body portion 31 and the cylinder sliding portion 32. The body sliding portion 33 is a sliding portion that is supported by the guide portion 25 of the nozzle hole 22 so as to be slidable in the axial direction. A notch 34 for forming a gap with the side wall of the nozzle hole 22 is formed at a portion where the body sliding portion 33 is formed. Since the notch portion 34 is formed in the needle 30, fuel can be circulated from the cylinder sliding portion 32 side to the valve body portion 31 side.

  The outer diameter between the cylinder sliding portion 32 and the body sliding portion 33 is smaller than the outer diameter of both the sliding portions 32, 33, and a step portion 35 is formed on the upper portion of the body sliding portion 33. Has been. A support ring 39 that supports a lower end portion of a coil spring 36 that urges the needle 30 downward, that is, in a direction in which the valve body portion 31 is seated on the valve seat 24, is attached to the step portion 35.

  The coil spring 36 is disposed between the support ring 39 and the cylinder 37 in a state compressed to some extent in the axial direction. Accordingly, the cylinder 37 is pressed against the lower end surface 41 of the orifice plate 40, and the needle 30 is pressed downward.

  As shown in FIG. 1, when the coil spring 36, the needle 30, and the cylinder 37 are accommodated in the nozzle hole 22, the fuel reservoir chamber 26 surrounded by the side wall of the nozzle hole 22, the needle 30, and the outer peripheral wall of the cylinder 37. Is formed. And the pressure control chamber 27 surrounded by the upper end part of the cylinder sliding part 32 of the needle 30, the inner peripheral wall 38 of the cylinder 37, and the lower end surface 41 of the orifice plate 40 is formed.

  The fuel reservoir chamber 26 is a space for accumulating high-pressure fuel injected from the injection hole 23 and communicates with the injection hole 23. When the needle 30 is seated on the valve seat 24, the communication between the fuel reservoir chamber 26 and the injection hole 23 is blocked, and fuel is not injected from the injection hole 23. When the needle 30 is separated from the valve seat 24, the fuel reservoir chamber 26 and the injection hole 23 communicate with each other, and fuel is injected from the injection hole 23.

  The pressure control chamber 27 is a space for accumulating high-pressure fuel that controls the axial movement of the needle 30. When fuel is supplied to the pressure control chamber 27, the pressure of the fuel acts on the upper end portion of the cylinder sliding portion 32, and a force for moving the needle 30 downward is generated. A method for controlling the movement of the needle 30 in the axial direction will be described later.

  The orifice plate 40 is formed in a substantially disk shape and is disposed between the nozzle body 21 and the valve body 50. In the orifice plate 40, a fuel supply passage 42, a first series passage 43, and a second communication passage 44 are formed so as to penetrate both end faces of the plate 40.

  One end of the fuel supply passage 42 is open to the fuel reservoir chamber 26 and is a passage for supplying high-pressure fuel in the common rail to the fuel reservoir chamber 26. The first series passage 43 is a passage that communicates the fuel reservoir chamber 26 with a valve chamber 52 formed in a valve body 50 described later. A substantially annular groove is formed in the lower end surface 41 of the orifice plate 40, and a fuel supply passage 42 and a first series passage 43 are opened at the bottom of the groove. The second communication passage 44 is a passage that communicates the pressure control chamber 27 and the valve chamber 52.

  The valve body 50 is formed in a substantially disk shape and is disposed between the orifice plate 40 and the lower body 70. In the valve body 50, a fuel supply passage 51, a valve chamber 52, a third communication passage 53, and a fuel passage 54 are formed.

  The fuel supply passage 51 communicates with the fuel supply passage 42 of the orifice plate 40 and is a passage for supplying high-pressure fuel to the fuel reservoir chamber 26 via the fuel supply passage 42.

  The valve chamber 52 accommodates the control valve 60 and the coil spring 63. The lower end of the valve chamber 52 is open. The valve chamber 52 communicates with the first and second communication passages 43 and 44.

  The third communication passage 53 is a passage that opens at the upper end surface of the valve chamber 52 and communicates the valve chamber 52 with a receiving hole 73 formed in a lower body 70 described later. A fuel passage 54 is opened at the upper end surface of the valve chamber 52. The fuel passage 54 is a passage for discharging surplus fuel not injected from the nozzle 20 to the low pressure side.

  The control valve 60 controls the flow of fuel in the first, second, and third communication passages 43, 44, 53 and the fuel passage 54. The control valve 60 has a low-pressure side seat 61 seated on the upper end surface of the valve chamber 52 and a high-pressure side seat 62 seated on the lower end surface of the valve chamber 52 (upper end surface of the orifice plate 40). The coil spring 63 always urges the control valve 60 toward the upper end surface of the valve chamber 52.

  When the low-pressure side seat 61 is seated on the upper end surface of the valve chamber 52, each of the third communication passage 53 and the fuel passage 54 is closed and the first series passage 43 is opened. As a result, the high-pressure fuel in the fuel reservoir chamber 26 is supplied to the pressure control chamber 27 through the first series passage 43 and the second communication passage. As a result, the pressure in the pressure control chamber 27 increases.

  When the high-pressure side seat 62 is seated on the lower end surface of the valve chamber 52, the first series passage 43 is closed and the third communication passage 53 and the fuel passage 54 are opened. As a result, the high-pressure fuel in the pressure control chamber 27 once flows into the valve chamber 52 through the second communication passage 44 and then flows into the third communication passage 53 and the fuel passage 54. As a result, the pressure in the pressure control chamber 27 decreases. Thus, the pressure in the pressure control chamber 27 is adjusted by operating the control valve 60 in the valve chamber 52.

  The lower body 70 is formed in a cylindrical shape, and an accommodation hole 73, a high pressure passage 75, and a low pressure passage 76 are formed therein. The housing hole 73, the high pressure passage 75 and the low pressure passage 76 are formed to extend in the axial direction of the lower body 70.

  The accommodation hole 73 accommodates the piezo actuator 90 and the driving force transmission portion 93. The lower end portion of the accommodation hole 73 communicates with the third communication passage 53 of the valve body 50. An opening 74 is formed in the outer peripheral wall 71 of the lower body 70. The upper end portion of the accommodation hole 73 is bent from the central axis side of the lower body 70 toward the outer peripheral wall 71 and communicates with the opening 74.

  The piezoelectric actuator 90 is obtained by alternately stacking piezoelectric ceramic layers such as PZT and electrode layers. A lead wire 91 is connected to the electrode layer, and charging / discharging by a drive circuit (not shown) causes the piezoelectric actuator 90 to expand and contract in the stacking direction (vertical direction). The lead wire 91 is taken out from the lower body 70 through an opening 74 of the accommodation hole 73 formed in the outer peripheral wall 71.

  As shown in FIG. 1, a connector 81 is formed on the lower body 70 with a resin 80 covering the opening 74. The lead wire 91 and the terminal 92 connected to the lead wire 91 are supported by the resin 80.

  The driving force transmission unit 93 is disposed below the piezo actuator 90 and transmits the displacement of the piezo actuator 90 to the control valve 60 via a pin 94 accommodated in the third communication path 53.

  When the piezo actuator 90 is energized via the drive circuit, the piezo actuator 90 expands. The driving force transmission unit 93 transmits the displacement in the extending direction of the piezo actuator 90 to the control valve 60 via the pin 94. As a result, the control valve 60 moves downward. As a result, the low pressure side seat 61 is separated from the upper end surface of the valve chamber 52, and the high pressure side seat 62 is seated on the lower end surface of the valve chamber 52.

  When the energization to the piezo actuator 90 is stopped, the electric charge of the piezo actuator 90 is released and the piezo actuator 90 contracts. The control valve 60 moves upward by the biasing force of the coil spring 63. As a result, the low pressure side seat 61 is seated on the upper end surface of the valve chamber 52, and the high pressure side seat 62 is separated from the lower end surface of the valve chamber 52.

  The high-pressure passage 75 is a passage for supplying high-pressure fuel from the common rail to the fuel reservoir chamber 26, and one end opens at the upper end portion of the lower body 70 and the other end communicates with the fuel supply passage 51 of the valve body 50. A male screw part 78 to which a fuel pipe for supplying high pressure fuel to the high pressure passage 75 is connected is formed at the upper end of the lower body 70.

  Further, as indicated by a broken line in FIG. 1, a low pressure passage 76 is formed in the lower body 70 in addition to the accommodation hole 73 and the high pressure passage 75. The low pressure passage 76 is a passage for discharging excess fuel that is not injected from the nozzle 20 to the outside of the injector 10. One end of the low pressure passage 76 communicates with the fuel passage 54 formed in the valve body 50. Further, as shown in FIGS. 2 and 3, an opening 77 is formed in the outer peripheral wall 71 of the lower body 70, and the other end of the low pressure passage 76 communicates with the opening 77.

  According to this configuration, the concave groove 102 having a simple structure is provided on the inner peripheral wall 101 of the ring member 100, and it is only attached to the outer peripheral wall 71 of the lower body 70 so that the concave groove 102 communicates with the opening 77 of the low pressure passage 76. Thus, the fuel passage 105 can be easily formed.

  As shown in FIGS. 2 and 3, a ring member 100 formed in an annular shape is provided on the outer peripheral wall 71 of the lower body 70. The ring member 100 covers the outer peripheral wall 71 of the lower body 70 over the entire circumference.

  An annular groove 102 is formed in the inner peripheral wall 101 of the ring member 100. By providing the ring member 100 on the outer peripheral wall 71 of the lower body 70, a fuel passage 105 formed by the concave groove 102 and the outer peripheral wall 71 is formed between the inner peripheral wall 101 of the ring member 100 and the outer peripheral wall 71 of the lower body 70. It is formed. The ring member 100 is provided at a position where the concave groove 102 communicates with the opening 77 of the low pressure passage 76.

  Two grooves 72 are formed on the outer peripheral wall 71 of the lower body 70 over the entire circumference. These grooves 72 are formed side by side in the axial direction so as to sandwich the opening 77 of the low pressure passage 76. An annular seal member 79 is fitted in the groove 72. As shown in FIG. 2, by attaching the ring member 100 to the outer peripheral wall 71, the ring member 100 comes into contact with the inner peripheral wall 101 of the ring member 100. As a result, the fuel passage 105 is sealed.

  A through hole 103 that communicates the fuel passage 105 with the outside of the ring member 100 is formed at the upper end in the axial direction of the ring member 100. A pipe 104 is connected to the through hole 103. The ring member 100 is embedded in the resin 80 forming the connector 81 and is fixed to the lower body 70. A part of the pipe 104 is also embedded in the resin 80. A fuel pipe that discharges excess fuel to the low pressure side (for example, a fuel tank) is connected to the pipe 104.

  Excess fuel discharged from the opening 77 of the low-pressure passage 76 flows in the circumferential direction along the outer peripheral wall 71 as shown by arrows in FIGS. 2 and 3, passes through the through-hole 103 and the pipe 104, and is injected into the injector 10. It is discharged outside.

  As described above, since the ring member 100 that forms the fuel passage 105 communicating with the opening 77 of the low pressure passage 76 is provided on the outer peripheral wall 71 of the lower body 70, the ring member 100 is simply rotated in the circumferential direction. The circumferential positions of the through-hole 103 and the pipe 104 communicating with the fuel pipe discharged to the pipe can be set at arbitrary positions. Thereby, the freedom degree of the circumferential position of the through-hole 103 and the pipe 104 connected to a fuel pipe can be increased compared with the conventional one.

  As a result, it is possible to attach to various types of engines without changing the arrangement of the high pressure passage 75, the low pressure passage 76 and the accommodation hole 73 formed in the lower body 70. That is, the lower body 70 can be shared. For this reason, it is not necessary to prepare the lower body 70 of the injector 10 for each type of engine, and the cost increase of the injector 10 can be suppressed.

  In the present embodiment, the concave groove 102 formed in the inner peripheral wall 101 of the ring member 100 may be arcuate rather than annular. It is sufficient that at least the concave groove 102 communicates with the opening 77 of the low pressure passage 76. Further, the ring member 100 itself does not need to be formed in an annular shape, like the concave groove 102.

  In the present embodiment, the surplus fuel is discharged from the pipe 104 connected to the through hole 103. However, the fuel pipe attached directly to the injector 10 is directly attached to the through hole 103. Also good.

  Next, the operation of the injector 10 configured as described above will be described with reference to FIG. When energization to the piezo actuator 90 is stopped and the internal charge is released, the piezo actuator 90 contracts, and the control valve 60 opens the first series passage 43 and opens the third communication passage 53 and the fuel passage 54. Block it. As a result, the high-pressure fuel supplied to the fuel reservoir chamber 26 flows into the pressure control chamber 27 through the first series passage 43 and the second communication passage 44.

  In the needle 30, the high pressure fuel in the pressure control chamber 27 acts on the upper end portion of the needle 30 to move the needle 30 downward (in the valve closing direction), and the urging force of the coil spring 36 moves the needle 30 downward. A force and a force that moves the needle 30 upward (in the valve opening direction) by the high pressure fuel in the fuel reservoir chamber 26 acting in the vicinity of the valve body portion 31 are acting.

  In the state where the high pressure fuel is supplied to the pressure control chamber 27, the force acting on the needle 30 is superior to the force to move upward than the force to move upward. The fuel is not injected from the nozzle hole 23.

  When the piezo actuator 90 is energized, the piezo actuator 90 extends, and the control valve 60 closes the first series passage 43 and opens the third communication passage 53 and the fuel passage 54. As a result, the high-pressure fuel in the pressure control chamber 27 flows into the fuel passage 54 through the second communication passage 44 and the valve chamber 52. The fuel that has flowed into the fuel passage 54 flows into the low pressure passage 76 formed in the lower body 70. The fuel discharged from the opening 77 of the low pressure passage 76 is discharged from the pipe 104 to the outside of the injector 10 through the fuel passage 105 formed by the ring member 100. As a result, the fuel pressure in the pressure control chamber 27 decreases.

  At this time, the force acting on the needle 30 is superior to the force that moves downward than the force that moves downward, so that the valve body 31 is separated from the valve seat 24 and fuel is injected from the injection hole 23. .

  Next, a method for attaching and fixing the ring member 100 will be described.

  First, the seal member 79 is attached to the lower body 70 in which the valve body 50, the orifice plate 40 and the nozzle 20 are assembled. Thereafter, the ring member 100 is inserted from the nozzle 20 side and attached to the lower body 70. At this time, the lead wire 91 and the terminal 92 of the piezoelectric actuator 90 are taken out of the lower body 70 from the opening 74 of the accommodation hole 73.

  In the present embodiment, since the fuel passage 105 is sealed by the seal member 79, it is not necessary to increase the accuracy of the inner diameter of the ring member 100. For this reason, it is not necessary to increase the dimensional accuracy of the outer diameters of the ring member 100 and the lower body 70. As a result, an increase in manufacturing cost of the injector 10 can be suppressed.

  Further, when the ring member 100 is annular, the relationship between the ring member 100 and the lower body 70 can be a clearance fit, so that the ring member 100 can be easily inserted from the end of the lower body 70.

  Furthermore, since the seal member 79 is fitted in the groove 72, the seal member 79 can be prevented from being displaced from a predetermined position when the ring member 100 is inserted into the lower body 70.

  Thereafter, the connector 81 is formed by covering the lower body 70 with the resin 80. The thing of the state mentioned above is installed in a metal mold | die. When installed in the mold, the lower body 70, the ring member 100, the pipe 104, and the terminal 92 are fixed at predetermined positions. Thereafter, molten resin 80 is poured into the mold. Here, the mold is formed so as to form a connector 81 and cover part of the ring member 100 and the pipe 104 when the resin 80 is poured. Thereby, the connector 81 is formed by the resin 80, and at the same time, the ring member 100 and the pipe 104 are firmly fixed to the injector 10.

(Modification of the first embodiment)
FIG. 4 shows a modification of the first embodiment. Components that are substantially the same as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted. In the modification shown in FIG. 4, the groove 72 a for accommodating the seal member 79 is formed not on the outer peripheral wall 71 of the lower body 70 but on the inner peripheral wall 101 of the ring member 100.

(Second Embodiment)
FIG. 5 shows a second embodiment, and FIG. 6 shows a modification thereof. Components that are substantially the same as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  In the second embodiment shown in FIG. 5, a recess 71 a that is recessed toward the central axis of the lower body 70 is formed in a portion where the opening 77 of the low pressure passage 76 of the lower body 70 is formed. Further, a groove 72 for accommodating the seal member 79 is formed in the recess 71a.

  The ring member 100 is attached to the recess 71a. Furthermore, the outer peripheral wall of the ring member 100 is covered with the resin 80 as in the first embodiment. Thereby, it can suppress that the outer diameter of the injector 10 when the outer peripheral side of the ring member 100 is covered with the resin 80 becomes large.

  In the modification shown in FIG. 6, a groove 72 a that accommodates the seal member 79 is formed in the inner peripheral wall 101 of the ring member 100 as in the modification of the first embodiment.

(Third embodiment)
FIG. 7 shows a third embodiment, and FIG. 8 shows a modification thereof. Constituent parts that are substantially the same as those in the embodiments are given the same reference numerals, and descriptions thereof are omitted.

  In the third embodiment shown in FIG. 7, the resin 80 a that covers the ring member 100 attached to the lower body 70 is separate from the resin 80 that forms the connector 81. In this way, the ring member 100 is fixed to the lower body 70 by the resin 80a different from the resin 80, so that the manufacture is facilitated.

  When the resin 80 forming the connector 81 also serves as a resin for fixing the ring member 100, as described in the first embodiment, before the resin 80 is poured into the molding die for molding the connector 81, The lower body 70, the terminal 92, the ring member 100, and the pipe 104 must be fixed at predetermined positions. The more members that are preliminarily fixed in the mold, the lower the work efficiency and the higher the production cost.

  In the present embodiment, the resin 80 a that fixes the ring member 100 is separated from the resin 80 that forms the connector 81. According to this, although the molding of the connector 81 and the fixing of the ring member 100 cannot be performed at the same time, the number of members to be previously fixed in the molding die can be reduced in each process. As a result, a decrease in work efficiency can be suppressed and an increase in manufacturing cost can be suppressed.

  In the modification shown in FIG. 8, a groove 72 a that accommodates the seal member 79 is formed in the inner peripheral wall 101 of the ring member 100 as in the modification of each embodiment.

(Fourth embodiment)
FIG. 9 shows a fourth embodiment, and FIG. 10 shows a modification thereof. Constituent parts that are substantially the same as those in the embodiments are given the same reference numerals, and descriptions thereof are omitted.

  In the fourth embodiment shown in FIG. 9, the concave groove 102 a forming the fuel passage 105 is formed not on the inner peripheral wall 101 of the ring member 100 but on the outer peripheral wall 71 of the lower body 70. A groove 72 for accommodating the seal member 79 is formed below and above the concave groove 102a. The outer peripheral wall of the ring member 100 is covered with the resin 80 that forms the connector 81 as in the first embodiment.

  In the modification shown in FIG. 10, a groove 72 a that accommodates the seal member 79 is formed in the inner peripheral wall 101 of the ring member 100 as in the modification of each embodiment.

(Fifth embodiment)
11 to 13 show a fifth embodiment, and FIG. 14 shows a modification thereof. Components that are substantially the same as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  The fifth embodiment shown in FIGS. 11 to 13 is different from the first to fourth embodiments in which the ring member 100 is fixed to the lower body 70 using the resins 80 and 80a, and the lower body 70 without using the resins 80 and 80a. The ring member 100 is fixed to the ring.

  Specifically, the ring member 100 is fixed to the lower body 70 by press-fitting and fixing a convex portion 711 protruding radially from the outer peripheral wall 71 of the lower body 70 into a groove portion 106 formed in the inner peripheral wall 101 of the ring member 100. Yes.

  As shown in FIGS. 11 and 12, a convex portion 711 protruding in the radial direction is formed on the outer peripheral wall 71 of the lower body 70. On the other hand, a groove 106 is formed in the inner peripheral wall 101 of the ring member 100 as shown in FIGS. As shown in FIG. 12, one end portion of the groove portion 106 opens on the end surface in the axial direction of the ring member 100.

  As shown in FIG. 13, the groove 106 is formed in a substantially L shape. The groove 106 includes an axial groove 107 extending in the axial direction from the opening 109 and a circumferential groove 108 connected to the axial groove 107 and extending in the circumferential direction. The groove width of the axial groove portion 107 is larger than the width of the convex portion 711. The groove width of the circumferential groove 108 becomes narrower toward the tip.

  The ring member 100 in which the groove 106 is formed is moved upward from below the lower body 70, and the convex portion 711 of the lower body 70 is inserted into the opening 109 of the groove 106. Then, the ring member 100 is moved further upward while guiding the convex portion 711 to the axial groove portion 107 as it is. Thereafter, the ring member 100 is rotated in the circumferential direction so that the circumferential groove 108 guides the convex portion 711. Since the groove width of the circumferential groove portion 108 becomes narrower toward the tip, the convex portion 711 is press-fitted into the circumferential groove portion 108. In this way, the ring member 100 is fixed to the lower body 70.

  In this embodiment, the groove portion 106 includes an axial groove portion 107 and a circumferential groove portion 108, and the convex portion 711 is press-fitted into the circumferential groove portion 108. According to this, the movement of the ring member 100 in the axial direction can be reliably prevented.

  In the modification shown in FIG. 14, a groove 72 a that accommodates the seal member 79 is formed in the inner peripheral wall 101 of the ring member 100 as in the modification of each embodiment.

It is sectional drawing of the injector by 1st Embodiment of this invention. It is sectional drawing to which the principal part of the injector by 1st Embodiment of this invention was expanded. It is sectional drawing of the part of the III-III line in FIG. It is sectional drawing to which the principal part of the injector by the modification of 1st Embodiment of this invention was expanded. It is sectional drawing to which the principal part of the injector by 2nd Embodiment of this invention was expanded. It is sectional drawing to which the principal part of the injector by the modification of 2nd Embodiment of this invention was expanded. It is sectional drawing to which the principal part of the injector by 3rd Embodiment of this invention was expanded. It is sectional drawing to which the principal part of the injector by the modification of 3rd Embodiment of this invention was expanded. It is sectional drawing to which the principal part of the injector by 4th Embodiment of this invention was expanded. It is sectional drawing to which the principal part of the injector by the modification of 4th Embodiment of this invention was expanded. It is sectional drawing to which the principal part of the injector by 5th Embodiment of this invention was expanded. It is sectional drawing of the XII-XII line | wire in FIG. It is sectional drawing of the XIII-XIII line | wire in FIG. It is sectional drawing to which the principal part of the injector by the modification of 5th Embodiment of this invention was expanded.

Explanation of symbols

  10 injector, 20 nozzle, 21 nozzle body, 22 nozzle hole, 23 nozzle hole, 26 fuel reservoir chamber, 27 pressure control chamber, 30 needle, 36 coil spring, 37 cylinder, 40 orifice plate, 42 fuel supply passage, 43 1st series Passage, 44 second communication passage, 50 valve body, 51 fuel supply passage, 52 valve chamber, 53 third communication passage, 54 fuel passage, 60 control valve, 63 coil spring, 70 lower body (body), 71 outer peripheral wall, 72 Groove, 73 receiving hole, 74 opening, 75 high pressure passage, 76 low pressure passage, 77 opening (opening), 79 seal member, 80 resin, 81 connector, 90 piezo actuator (driving means), 91 lead wire (driving means) ), 92 terminal, 93 driving force transmission part, 94 pin, 100 ring member (Passage member), 101 inner peripheral wall, 102 concave groove, 103 through hole (extraction part), 104 pipe (extraction part), 105 fuel passage (fuel passage), 110 retaining nut

Claims (13)

A nozzle having a nozzle hole at the tip and a needle for controlling the opening and closing of the nozzle hole inside;
A high-pressure passage that is formed in a cylindrical shape, supports the nozzle at an end, and supplies fuel to the nozzle inside, a low-pressure passage that discharges excess fuel not injected by the nozzle to a low-pressure side, and the needle A body in which housing holes for housing driving means for controlling the opening and closing operations are respectively formed extending in the axial direction, and an opening of the low-pressure passage is formed in the outer peripheral wall;
By covering the outer peripheral wall of the body, a fuel passage is formed between the inner peripheral wall and the outer peripheral wall so as to communicate with the opening and distribute the surplus fuel discharged from the opening in the circumferential direction. And further comprising a passage member having an extraction portion communicating with the fuel passage ,
At the end of the body opposite to the side where the nozzle is attached, a connector is provided that supports an electric wire that is formed of resin and supplies power to the driving means.
The injector , wherein the passage member is embedded in the resin forming the connector .   2. The passage groove portion extending in the circumferential direction is formed on the inner peripheral wall of the passage member or the outer peripheral wall facing the inner peripheral wall of the passage member of the body. Injector.   The injector according to claim 1, wherein a seal member that surrounds the fuel passage is provided between the inner peripheral wall of the passage member and the outer peripheral wall of the body.   The injector according to claim 3, wherein the seal member is fitted into a seal groove formed in the inner peripheral wall of the passage member or the outer peripheral wall of the body. The injector according to any one of claims 1 to 4, wherein the passage member is fitted in a recess formed in the outer peripheral wall of the body. A nozzle having a nozzle hole at the tip and a needle for controlling the opening and closing of the nozzle hole inside;
A high-pressure passage that is formed in a cylindrical shape, supports the nozzle at an end, and supplies fuel to the nozzle inside, a low-pressure passage that discharges excess fuel not injected by the nozzle to a low-pressure side, and the needle A body in which housing holes for housing driving means for controlling the opening and closing operations are respectively formed extending in the axial direction, and an opening of the low-pressure passage is formed in the outer peripheral wall;
By covering the outer peripheral wall of the body, a fuel passage is formed between the inner peripheral wall and the outer peripheral wall so as to communicate with the opening and distribute the surplus fuel discharged from the opening in the circumferential direction. And further comprising a passage member having an extraction portion communicating with the fuel passage,
The outer peripheral wall of the body is provided with a convex portion protruding in the radial direction,
One end of the inner peripheral wall of the passage member is open to an axial end surface of the passage member, and the convex portion is a groove portion that can be inserted from the opening, and the convex portion is extended from the one end portion to the other end portion. features and to Louis Njekuta that the groove groove width as is inserted narrows toward the formed. Said outer peripheral wall facing the inner wall or the inner wall of the passage member of said body, said passage member is as claimed in claim 6, characterized in that passage groove extending in the circumferential direction is formed Injector. The injector according to claim 6 or 7 , wherein a seal member surrounding the fuel passage is provided between the inner peripheral wall of the passage member and the outer peripheral wall of the body . The injector according to claim 8, wherein the seal member is fitted into a seal groove formed in the inner peripheral wall of the passage member or the outer peripheral wall of the body . The injector according to any one of claims 6 to 9 , wherein the passage member is embedded in a resin provided on the outer peripheral wall of the body . The groove portion has one end side extending in the axial direction of the passage member, the groove width being larger than the width of the convex portion, and being connected to the axial groove in the circumferential direction of the passage member. The injector according to any one of claims 6 to 10, wherein the injector extends from the circumferential direction groove portion and the groove width becomes narrower toward the other end portion side. The injector according to any one of claims 6 to 11, wherein the passage member is fitted in a recess formed in the outer peripheral wall of the body. At the end of the body opposite to the side where the nozzle is attached, a connector is provided that supports an electric wire that is formed of resin and supplies power to the driving means.
  The injector according to any one of claims 6 to 12, wherein the passage member is embedded in a resin different from the resin forming the connector.

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