JP5240019B2 - Fuel injection valve and internal electric connection method of fuel injection valve - Google Patents

Description

  The present invention relates to a fuel injection valve that is mounted on an internal combustion engine and injects fuel for combustion from an injection hole.

  In order to accurately control the output torque and the emission state of the internal combustion engine, it is important to accurately control the injection state such as the injection start timing and the injection amount of the fuel injected from the fuel injection valve. Therefore, conventionally, there has been proposed a technique for detecting an actual injection state by detecting the pressure of fuel that fluctuates with the injection. For example, the actual injection start time can be detected by detecting the time when the fuel pressure starts to decrease with the start of injection, or the actual injection end time can be determined by detecting the time when the increase in fuel pressure has stopped with the end of injection. It is detected (see Patent Document 1).

  When detecting such fluctuations in fuel pressure, the fuel pressure sensor (rail pressure sensor) installed directly on the common rail (accumulation vessel) buffers the fuel pressure fluctuation caused by injection in the common rail. Variation cannot be detected. Therefore, in the invention described in Patent Document 1, by mounting a fuel pressure sensor on the fuel injection valve, the fuel pressure fluctuation is detected before the fuel pressure fluctuation caused by the injection is buffered in the common rail.

JP 2008-144749

  The present inventors have studied a structure in which a screw part is formed in the fuel pressure sensor and the fuel pressure sensor is screwed to the body of the fuel injection valve. However, in this structure, when the screw fastening is completed by rotating the fuel pressure sensor, the rotational position of the fuel pressure sensor is not fixed at a specific position. Therefore, the rotational direction position of the terminal (sensor terminal) provided in the fuel pressure sensor is unspecified.

  On the other hand, since the connector attached to the body needs to be attached to a specific predetermined position in the body, the connector terminal (connector terminal) arranged on the body in this way and the sensor terminal whose rotational direction position is unspecified. It is difficult to electrically connect the two. In other words, it is difficult to perform screw fastening so that the sensor terminal is positioned at a pinpoint position facing the connector terminal when the screw fastening is completed.

  In addition, these terminals include not only a terminal for outputting a detection signal of the fuel pressure sensor, but also a terminal for supplying power, a grounding terminal, and the like. Therefore, each of the plurality of connector terminals and sensor terminals must be electrically connected. Don't be. Therefore, for example, even if it is going to connect both terminals with an electric wire, adjacent electric wires will interfere and it will short-circuit. Moreover, even if it tries to avoid a short circuit using the electric wire which carried out the insulation coating of the conducting wire, there is a concern that the interfering electric wires vibrate together with the vibration of the internal combustion engine, resulting in disconnection due to friction.

  SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems. An object of the present invention is to provide a fuel injection valve including a fuel pressure sensor that is screw-fastened, and a connector terminal attached to a body and a fuel pressure sensor terminal. It is an object of the present invention to provide a fuel injection valve that can be easily electrically connected, and an internal electrical connection method of the fuel injection valve.

  Hereinafter, means for solving the above-described problems and the operation and effects thereof will be described.

  According to the first aspect of the present invention, there is provided a body that forms a high-pressure passage through which high-pressure fuel flows into the nozzle hole, a fuel pressure sensor that is attached to the body and detects the pressure of the high-pressure fuel, and the fuel pressure sensor. A plurality of sensor terminals including at least a terminal for outputting a detection signal of the fuel pressure sensor; a plurality of connector terminals held in a connector housing attached to the body; and each of the connector terminal and the sensor terminal is electrically connected And a plurality of electrodes to be connected.

  The fuel pressure sensor includes a screw portion that is screwed to the body, and is configured to rotate together with the sensor terminal when the screw portion is fastened. The plurality of electrodes are the rotation centers of the fuel pressure sensor. It has an arcuate connection part that is formed in a shape extending in an arcuate shape and is electrically connected to either the connector terminal or the sensor terminal, and each of the arcuate connection parts extends along the rotation center direction of the fuel pressure sensor. Thus, a plurality of layers are arranged side by side in different positions.

  According to this, since both terminals are electrically connected via the arc-shaped connection portion extending in an arc shape around the rotation center of the fuel pressure sensor, the rotational direction position of the fuel pressure sensor at the time when the screw fastening is completed is unspecified. However, if the part (hereinafter referred to as “connection part”) of both terminals that is electrically connected to the arcuate connection part is located in the arc range of the arcuate connection part, the terminal connection part and the arcuate connection part And can be easily electrically connected.

  For example, when the fuel pressure sensor is rotated in a state where the electrode is connected to the sensor terminal, the arc range of the arc-shaped connection portion at the time of completion of screw fastening may be positioned at the connection portion of the connector terminal. In addition, when the fuel pressure sensor is rotated without connecting the electrode to the sensor terminal, it is only necessary that the connection portion of the sensor terminal at the time of completion of screw fastening is located in the arc range of the arc-shaped connection portion.

  As described above, according to the present invention, it is possible to easily make the terminal connection portion and the arc-shaped connection portion face each other without having to set the rotational position of the fuel pressure sensor at the time of completion of screw fastening to a predetermined pinpoint position. It is possible to easily realize electrical connection between both terminals via the electrodes.

  Further, in the above invention, since each of the arc-shaped connecting portions is arranged in a plurality of layers in a layered manner along the rotation center direction of the fuel pressure sensor, a plurality of terminal connection portions are arranged in the rotation center direction. If it arrange | positions facing an arc-shaped connection part, interference of adjacent electrical connection paths can be avoided easily.

Furthermore, in the above invention, since the portion (arc-shaped connecting portion) of the electrode connected to the terminal connection portion is formed in an arc shape, compared to the case where it is formed in an annular shape as in the first invention described later, As described, the electrodes can be easily formed. That is, in the case of an arc shape, the electrode can be developed in a planar shape, so that the electrode can be formed on a metal plate as a base material by planar development and press forming. On the other hand, in the case of an annular shape, it is difficult to expand the electrode in a planar shape, and thus it is difficult to form the electrode by press molding. Therefore, it is more advantageous to use an arc than an annular shape in terms of electrode formability.

  According to a second aspect of the present invention, the connector terminal has at least two welded portions that can contact the arcuate connection portion, and the fuel pressure sensor is electrically connected to the sensor terminal. The distance between the two welded portions (see symbol L1 in FIG. 3A) is the distance between the arc ends of the arc-shaped connecting portion (see FIG. 3A). It is characterized in that it is set longer than the reference L2 in the figure).

  According to this, the connection part (welding part) of a connector terminal is formed in two or more places, and the interval between the two welding parts is set to be longer than the distance between the arc ends of the arcuate connection part. Even if one welded part is not located in the arc range, the other welded part is always located in the arc range. Therefore, the welded portion of the connector terminal and the arc-shaped connecting portion of the electrode can be reliably electrically connected regardless of the rotational direction position of the fuel pressure sensor.

In the first invention, a body that forms a high-pressure passage for circulating high-pressure fuel to the nozzle hole, a fuel pressure sensor that is attached to the body and detects the pressure of the high-pressure fuel, and provided in the fuel pressure sensor, A plurality of sensor terminals including at least a terminal for outputting a detection signal of a fuel pressure sensor, a plurality of connector terminals held in a connector housing attached to the body, and each of the connector terminals and the sensor terminals are electrically connected. And a plurality of electrodes.

The fuel pressure sensor has a screw portion that is screwed to the body, and is configured to rotate together with the sensor terminal when the screw portion is fastened.
The plurality of electrodes have an annular connection part formed in an annular shape around the rotation center of the fuel pressure sensor and electrically connected to either the connector terminal or the sensor terminal,
Each of the annular connecting portions is arranged concentrically by arranging a plurality of layers in a layered manner along the rotational center direction of the fuel pressure sensor.

  According to this, in the above invention, since both terminals are electrically connected via the annular connecting portion extending in an annular shape around the rotation center of the fuel pressure sensor, the rotational position of the fuel pressure sensor at the time when the screw fastening is completed. Regardless of this, the part (connection part) that is electrically connected to the annular connection part of both terminals faces the annular connection part. Therefore, since it is not necessary to set the rotational position of the fuel pressure sensor at the time of completion of screw fastening to a predetermined pinpoint position, the connection portion of the terminal and the annular connection portion can be easily opposed to each other, so that both terminals are connected via the electrodes. Can be easily connected to each other.

  Further, in the above invention, since each of the annular connecting portions is arranged in a concentric circle in a layered manner along the direction of the rotation center of the fuel pressure sensor and arranged in layers, a plurality of terminal connection portions are arranged in the direction of the rotation center. If they are arranged side by side and opposed to the respective annular connection portions, interference between adjacent electrical connection paths can be easily avoided.

The electrode may be electrically connected to the sensor terminal before the fuel pressure sensor is screwed as in the second invention , or may be electrically connected to the sensor terminal after the fuel pressure sensor is screwed. And, in the case of the second invention to be connected before screw fastening, a welded portion that is electrically connected to the annular connection portion may be formed on the connector terminal, and when connecting after screw fastening, What is necessary is just to form the welding part electrically connected to the said annular | circular shaped connection part in the said sensor terminal. In addition, if the welding part of a terminal is made into the shape which protruded toward the connection part, especially in the case of laser welding, it is suitable for concentrating the energy of a laser to a welding part.

According to a third aspect of the present invention, the electrode is molded with a mold resin in a state where the connection surface of the connection portion is exposed, and the electrode has a groove portion that is recessed from the connection surface. The electrode is molded so that the mold resin flows into the groove.

  If the groove portion is not formed contrary to the above invention, there is a concern that the electrode connection portion (arc-shaped connection portion or annular connection portion) is lifted off from the mold resin. On the other hand, in the above invention, a groove portion that is depressed from the connection surface exposed from the mold resin is formed, and the mold resin flows into the groove portion. The arc-shaped connecting portion or the annular connecting portion) is locked so that the lifting does not occur. Therefore, the above concerns can be resolved.

According to a fourth aspect of the present invention, the connection surfaces of the connection portions are arranged on the same plane.

  Therefore, it is possible to reduce the size of the electrode in the rotational radial direction of the fuel pressure sensor compared to the case where the connection surfaces are not arranged in the same plane but at different positions in the rotational radial direction. Can be reduced in size in the rotational radial direction. In addition, for example, when laser welding a plurality of connection portions, welding can be improved because the laser irradiation position can be moved on the same plane and welding can be performed.

According to a fifth aspect of the present invention, the apparatus includes a driving unit for driving a needle that opens and closes the high-pressure passage, and a driving terminal that supplies power to the driving unit, and the driving terminal is held by the connector housing. The connector terminal and the drive terminal are configured as a common connector.

  In short, a common connector housing holds a drive terminal to which electric power is supplied to the drive means for driving the needle and a sensor terminal for outputting a detection signal from the fuel pressure sensor to the outside. And one connector is comprised by a drive terminal.

  Therefore, a fuel pressure sensor can be mounted on the fuel injection valve without increasing the number of connectors, and a harness for connecting an external device such as an engine ECU and the connector is gathered from one connector provided on the fuel injection valve. It will be extended. Therefore, the handling of the harness can be simplified. Further, it is possible to avoid an increase in labor for connector connection work.

The invention according to claim 6 is an internal electrical connection method of the fuel injection valve, wherein a sensor terminal connection step of electrically connecting the electrode to the sensor terminal, and after the sensor terminal connection step, the fuel pressure sensor is connected to the sensor terminal. A fastening step of rotating together with the sensor terminal and the electrode to screw the fuel pressure sensor to the body; and a connector terminal connecting step of electrically connecting the connector terminal to the connecting portion of the electrode after the fastening step; It is characterized by including.

  According to this, at the time when the screw fastening of the fuel pressure sensor is completed by the fastening process, the rotational direction positions of the sensor terminal and the electrode are unspecified, but the electrode connection part (arc-shaped connection part or annular connection part) The position facing the connection portion of the connector terminal can be easily realized as compared with the case where the rotational position of the fuel pressure sensor is set to a predetermined pinpoint position. Therefore, in the subsequent connector terminal connection step, the electrode connection portion and the connector terminal can be easily electrically connected, and as a result, both the terminals can be easily electrically connected via the electrode.

By the way, as a specific example of the structure in which the fuel pressure sensor is screwed to the body as in the invention of the first aspect and the first invention , there is a structure in which a screw part is formed on the outer peripheral surface of the cylindrical part described below.

  That is, the fuel pressure sensor is positioned so as to close the other end of the cylindrical portion having a cylindrical portion formed at one end with an introduction port for introducing the high pressure fuel therein, and receives the pressure of the high pressure fuel. A disk-shaped diaphragm part that is elastically deformed, and a sensor element that is attached to the diaphragm part, converts the magnitude of distortion generated in the diaphragm part into an electrical signal, and outputs it as the detection signal. The screw portion is formed on the outer peripheral surface of the cylindrical portion.

It is a typical sectional view showing an outline internal composition of an injector concerning a 1st embodiment of the present invention. The enlarged view of FIG. 1 which shows the assembly | attachment structure to the injector of a fuel pressure sensor. In 1st Embodiment, (a) is a figure which shows the connection structure of an electrode, (b) is AA sectional drawing of (a). In 2nd Embodiment of this invention, (a) is a figure which shows the connection structure of an electrode, (b) is AA sectional drawing of (a). The figure which shows the connection structure of an electrode in 3rd Embodiment of this invention. In the reference example of this invention, (a) is a figure which shows the connection structure of an electrode, (b) is AA sectional drawing of (a). In 4th Embodiment of this invention, (a) is a figure which shows the connection structure of an electrode, (b) is AA sectional drawing of (a).

  Hereinafter, embodiments embodying the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other are denoted by the same reference numerals in the drawings, and the description of the same reference numerals is used.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic sectional view showing a schematic internal configuration of an injector (fuel injection valve) according to the present embodiment. First, the basic configuration and operation of the injector will be described with reference to FIG.

  The injector is for injecting high pressure fuel stored in a common rail (pressure accumulating vessel) (not shown) into a combustion chamber E1 formed in a cylinder of a diesel internal combustion engine. An electric actuator 2 (drive means) that is supplied and driven, and a back pressure control mechanism 3 that is driven by the electric actuator 2 to control the back pressure of the nozzle 1 are provided.

  The nozzle 1 includes a nozzle body 12 in which an injection hole 11 is formed, a needle 13 that opens and closes the injection hole 11 in contact with and away from the valve seat of the nozzle body 12, and a spring 14 that urges the needle 13 in a valve closing direction.

  The electric actuator 2 employs a piezo actuator composed of a laminated body (piezo stack) formed by laminating a large number of piezo elements. By switching between charging and discharging of the piezo elements, an extension state and a contraction state are achieved. Is switched. Accordingly, the piezo stack functions as an actuator that operates the needle 13. In place of the piezo actuator, an electromagnetic actuator constituted by a stator and an armature may be employed.

  The valve body 31 of the back pressure control mechanism 3 is driven by a piston 32 that moves following the expansion and contraction of the piezoelectric actuator 2, a disc spring 33 that biases the piston 32 toward the piezoelectric actuator 2, and a piston 32. A spherical valve element 34 is accommodated.

  The substantially cylindrical injector body 4 is formed with a stepped columnar storage hole 41 extending in the axial direction of the injector (vertical direction in FIG. 1) at the center in the radial direction. And the back pressure control mechanism 3 is accommodated. Further, the nozzle 1 is held at the end of the injector body 4 by screwing the substantially cylindrical retainer 5 into the injector body 4.

  The nozzle body 12, the injector body 4, and the valve body 31 are formed with a high-pressure passage 6 to which high-pressure fuel is always supplied from the common rail, and a low-pressure passage 7 connected to a fuel tank (not shown). These bodies 12, 4 and 31 are made of metal, and are inserted into an insertion hole E3 formed in the cylinder head E2 of the internal combustion engine. The injector body 4 is formed with an engaging portion 42 that engages with one end of the clamp K. By tightening the other end of the clamp K to the cylinder head E2 with a bolt, one end of the clamp K inserts the engaging portion 42. It will be pressed toward the hole E3. Thereby, an injector is fixed in the state pressed in insertion hole E3.

  A high pressure chamber 15 serving as a part of the high pressure passage 6 is formed between the outer peripheral surface of the needle 13 on the nozzle hole 11 side and the inner peripheral surface of the nozzle body 12. The high pressure chamber 15 communicates with the nozzle hole 11 when the needle 13 is displaced in the valve opening direction. A back pressure chamber 16 is formed on the side opposite to the injection hole of the needle 13. In the back pressure chamber 16, the above-described spring 14 is disposed.

  The valve body 31 is formed with a high-pressure seat surface 35 in a path communicating the high-pressure passage 6 in the valve body 31 and the back pressure chamber 16 of the nozzle 1, and the back of the low-pressure passage 7 in the valve body 31 and the nozzle 1. A low-pressure seat surface 36 is formed in a path communicating with the pressure chamber 16. The valve body 34 described above is disposed between the high pressure seat surface 35 and the low pressure seat surface 36.

  The injector body 4 is formed with a high pressure port 43 (high pressure piping connection portion) connected to a high pressure piping (not shown) and a low pressure port 44 (low pressure piping connection portion) connected to a low pressure piping (not shown). The fuel supplied from the common rail to the high-pressure port 43 through the high-pressure pipe is supplied from the outer peripheral surface side of the cylindrical injector body 4. The fuel supplied to the injector flows into the high pressure chamber 15 and the back pressure chamber 16 through the high pressure passage 6.

  In the high-pressure passage 6, a branch passage 6 a that branches to the side opposite to the injection hole of the injector body 4 is formed. By this branch passage 6a, the fuel in the high pressure passage 6 is introduced into a fuel pressure sensor 50 described later.

  A connector 60 is attached to the upper part of the injector body 4 on the side opposite to the injection hole. The electric power supplied from the outside to the terminal of the connector 60 (drive connector terminal 62) is supplied to the piezo actuator 2 via the lead wire 21, whereby the piezo actuator 2 expands and contracts when the power supply is stopped.

  In the above configuration, when the piezo actuator 2 is contracted, the valve body 34 is in contact with the low pressure seat surface 36 and the back pressure chamber 16 is connected to the high pressure passage 6 as shown in FIG. Fuel pressure is introduced. The needle 13 is urged in the valve closing direction by the fuel pressure in the back pressure chamber 16 and the spring 14 to close the nozzle hole 11.

  On the other hand, when a voltage is applied to the piezo actuator 2 and the piezo actuator 2 is extended, the valve body 34 is in contact with the high pressure seat surface 35, the back pressure chamber 16 is connected to the low pressure passage 7, and the back pressure chamber 16 has a low pressure. become. The needle 13 is urged in the valve opening direction by the fuel pressure in the high pressure chamber 15 to open the injection hole 11, and fuel is injected from the injection hole 11 into the combustion chamber E <b> 1.

  Here, the pressure of the high-pressure fuel in the high-pressure passage 6 varies with fuel injection from the nozzle hole 11. A fuel pressure sensor 50 that detects this pressure fluctuation is attached to the injector body 4. In the pressure fluctuation waveform detected by the fuel pressure sensor 50, the actual injection start timing can be detected by detecting the timing when the fuel pressure starts to decrease with the start of injection from the nozzle hole 11. Moreover, the actual injection end time can be detected by detecting the time when the fuel pressure starts to increase with the end of injection. Further, in addition to the injection start timing and the injection end timing, the injection amount can be detected by detecting the maximum value of the fuel pressure decrease amount caused by the injection.

  Next, the single-piece | unit structure of the fuel pressure sensor 50 and the attachment structure to the injector body 4 of the fuel pressure sensor 50 are demonstrated using FIG.

  The fuel pressure sensor 50 receives a pressure of the high-pressure fuel in the branch passage 6a and elastically deforms the stem 51 (a strain generating body), and converts the magnitude of the strain generated in the stem 51 into an electric signal as a pressure detection value. A strain gauge 52 (sensor element) for output, a mold IC 54 for processing a detection signal output from the strain gauge 52, a plate 53 for holding the mold IC 54, and the like are provided.

  The stem 51 includes a cylindrical cylindrical portion 51b having an inlet 51a for introducing high-pressure fuel therein, and a disc-shaped diaphragm portion 51c closing the other end of the cylindrical portion 51b. ing. The pressure of the high-pressure fuel flowing into the cylindrical portion 51b from the introduction port 51a is received by the inner surface of the cylindrical portion 51b and the diaphragm portion 51c, whereby the entire stem 51 is elastically deformed.

  A concave portion 45 into which the cylindrical portion 51b of the stem 51 is inserted is formed on the end surface of the cylindrical injector body 4 on the side opposite to the injection hole. A female screw portion is formed on the inner peripheral surface of the recess 45, and a male screw portion 51d is formed on the outer peripheral surface of the cylindrical portion 51b. The fuel pressure sensor 50 is attached to the injector body 4 by screwing the male screw portion 51 d of the stem 51 into the recess 45 of the injector body 4.

  The strain gauge 52 is attached to the diaphragm portion 51c. More specifically, the strain gauge 52 is fixed by being sealed (baked) by the glass member 52b while being disposed on the diaphragm portion 51c. Therefore, when the stem 51 is elastically deformed so as to expand due to the pressure of the high-pressure fuel flowing into the cylindrical portion 51b, the strain gauge 52 detects the magnitude of the strain (elastic deformation amount) generated in the diaphragm portion 51c. .

  A disc-shaped metal plate 53 is attached to the stem 51, and a mold IC 54 described in detail later is fixedly supported on the plate 53.

  The mold IC 54 is electrically connected to the strain gauge 52 by wire bond W, and the electronic component 54a and sensor terminals 54b, 54c, 54d, 54e (see FIG. 3A) are sealed with a mold resin 54m. Has been. The electronic component 54a constitutes an amplifier circuit that amplifies the detection signal output from the strain gauge 52, a filtering circuit that removes noise superimposed on the detection signal, a circuit that applies a voltage to the strain gauge 52, and the like.

  Note that the strain gauge 52 to which a voltage is applied from the voltage application circuit constitutes a bridge circuit whose resistance value changes in accordance with the magnitude of the strain generated in the diaphragm portion 51c. As a result, the output voltage of the bridge circuit changes according to the distortion of the diaphragm portion 51c, and the output voltage is output to the amplification circuit of the mold IC 54 as the pressure detection value of the high-pressure fuel. The amplifier circuit amplifies the pressure detection value output from the strain gauge 52 (bridge circuit), and outputs the amplified signal from the sensor terminal 54b.

  The mold resin 54m is formed in a cylindrical shape extending annularly along the outer peripheral surface of the cylindrical portion 51b of the stem 51. A plurality of sensor terminals 54b to 54e extend from the outer peripheral surface of the mold resin 54m. These sensor terminals 54b to 54e are electrically connected to the electronic component 54a inside the mold IC 54, and function as terminals for outputting detection signals of the fuel pressure sensor, terminals for supplying power, terminals for grounding, and the like. .

  Of these sensor terminals 54b to 54e, portions extending in the horizontal direction from the outer peripheral surface of the mold resin 54m are bent so as to extend toward the counter-injection hole in the axial direction of the injector (vertical direction in FIG. 2). ing. The extended upper end portion functions as a connection portion 55 that is electrically connected to electrodes 71 to 74 described later by welding or the like, and the injector axial direction position of the connection portion 55 is any of the plurality of sensor terminals 54b to 54e. Is in the same position.

  A case 56 is attached to the outer peripheral end of the plate 53. In the case 56 and the plate 53, a portion of the cylindrical portion 51b of the stem 51 excluding the male screw portion 51d, the strain gauge 52, and the mold IC 54 are accommodated. Thereby, the metal case 56 and the plate 53 block external noise and protect the strain gauge 52 and the mold IC 54. An opening 56a is formed on the outer peripheral surface of the case 56, and the sensor terminals 54b to 54e extend from the inside of the case 56 to the outside through the opening 56a.

  The housing 61 of the connector 60 described above holds the sensor connector terminals 81, 82, 83, and 84 (see FIG. 3A) together with the drive connector terminal 62. The connector 60 is connected to a connector of an external harness that is connected to an external device such as an engine ECU (not shown). Thereby, the pressure detection signal output from mold IC54 is input into engine ECU via an external harness.

  Each of the portions extending in the horizontal direction from the connector housing 61 of the sensor connector terminals 81 to 84 is disposed at the same position in the axial direction of the injector. These connector terminals 81 to 84 and sensor terminals 54b to 54e are electrically connected by electrodes 71, 72, 73, and 74, which will be described in detail later. In the present embodiment, the electrodes 71 to 74 and the terminals 81 to 84, 54b to 54e are electrically connected by laser welding, but may be connected by means such as soldering, fusing welding, resistance welding or the like.

  Next, the electrodes 71 to 74, which are the main parts of the present embodiment, will be described in detail with reference to FIG.

  FIG. 3 is a view showing the assembly As and the connector terminals 81 to 84 in which the fuel pressure sensor 50, the plate 53, the mold IC 54, the case 56, and the electrodes 71 to 74 are integrated, and FIG. FIG. 2 shows an AA cross section of FIG.

  The plurality of electrodes 71 to 74 are disposed above the case 56. The electrodes 71 to 74 include arcuate connection portions 71a, 72a, 73a, and 74a that are electrically connected to the connector terminals 81 to 84, and extending portions 71b, 72b, 73b, and 74b that are electrically connected to the sensor terminals 54b to 54e. Have

  The arc-shaped connecting portions 71 a to 74 a have a shape extending in an arc shape around the rotation center of the stem 51, and the outer peripheral surface of the arc is connected to the connector terminals 81 to 84. Further, the plurality of arcuate connection portions 71 a to 74 a are provided at different positions by being arranged in the direction of the rotation center of the stem 51 (the vertical direction in FIG. 3B). Thereby, it arrange | positions at layer form so that each outer peripheral surface of circular arc-shaped connection part 71a-74a may be located in the same plane shape.

  The extending portions 71b to 74b have a shape that hangs in the direction of the rotation center from the inner peripheral side of the arc-shaped connecting portions 71a to 74a toward the sensor terminals 54b to 54e, and the extending end portions of the extending portions 71b to 74b are It is electrically welded to the connecting portion 55 of the sensor terminals 54b to 54e.

  The connector terminals 81 to 84 can form first contact points (welded portions 80P) between the external connection portions 81a, 82a, 83a and 84a connected to an external connector (not shown) and the arc-shaped connection portions 71a to 74a. 1 extension part 81b, 82b, 83b, 84b and 2nd extension part 81c, 82c, 83c, 84c which can form the 2nd contact point (welding part 80Q) with circular arc-shaped connection part 71a-74a. Have.

  The plurality of external connection portions 81a to 84a are arranged horizontally on the same plane. The plurality of first extending portions 81b to 84b are arranged in the vertical direction so as to face the outer peripheral surfaces of the arc-shaped connecting portions 71a to 74a. Moreover, the 1st extension parts 81b-84b are the shapes extended linearly in the tangent direction of the arc-shaped connection parts 71a-74a, and are in point contact with the arc-shaped connection parts 71a-74a. This point contact portion becomes the above-described welded portion 80P.

  Second extending portions 81c to 84c extend in the horizontal direction from the extending ends of the first extending portions 81b to 84b. Similarly to the first extending portions 81b to 84b, the second extending portions 81c to 84c are arranged side by side in the vertical direction so as to face the outer peripheral surfaces of the arc connecting portions 71a to 74a, and the arc connecting portions 71a to 74a. The shape extends linearly in the direction of the tangent to the arc-shaped connecting portions 71a to 74a. This point contact portion becomes the above-described welded portion 80Q.

  Accordingly, the first extending portions 81b to 84b and the second extending portions 81c to 84c extend in different directions, and contact at different portions (welded portions 80P and 80Q) of the arc-shaped connecting portions 71a to 74a. Become. And the space | interval L1 of the two welding parts 80P and 80Q is set longer than the space | interval L2 of the circular arc both ends of circular arc-shaped connection part 71a-74a.

  Next, a procedure for attaching the fuel pressure sensor 50 and the like to the injector body 4 and a procedure for electrically connecting the terminals 81 to 84 and 54b to 54e via the electrodes 71 to 74 will be described.

  First, the assembly As shown in FIG. 3 is assembled. Specifically, the plate 53 is assembled to the stem 51 to which the strain gauge 52 is attached, and then the mold IC 54 is fixed to the plate 53. Thereafter, the mold IC 54 and the strain gauge 52 are connected by the wire bond W using a bonding machine. Thereafter, the case 56 is attached to the plate 53.

  Next, the extending portions 71b to 74b of the electrodes 71 to 74 and the connecting portions 55 of the sensor terminals 54b to 54e are electrically connected by laser welding or the like (sensor terminal connecting step). Thus, the assembly of the assembly As is completed.

  The plurality of electrodes 71 to 74 are punched out from a base material plate (not shown) by pressing, and then the portions corresponding to the arc-shaped connecting portions 71a to 74a are bent into an arc shape to correspond to the extending portions 71b to 74b. The part is formed by bending.

  Next, the assembly As is attached to the injector body 4. Specifically, the male screw portion 51d of the stem 51 is screwed to the concave portion 45 of the injector body 4 (fastening process).

  Next, the connector terminals 62 and 81 to 84 are positioned with respect to the injector body 4. That is, the sensor connector terminals 81 to 84 are arranged at predetermined positions in the axial direction, the radial direction, and the circumferential direction of the injector body 4.

  Next, the drive connector terminal 62 and the lead wire 21 are electrically connected, and the sensor connector terminals 81 to 84 and the electrodes 71 to 74 are electrically connected by laser welding or the like (connector terminal connection step). That is, laser welding is performed on the welded portions 80P and 80Q of the extending portions 81b to 84b and 81c to 84c and the outer peripheral surfaces of the arc-shaped connecting portions 71a to 74a. Irrespective of whether or not the welded portions 80P and 80Q are at positions facing the arc-shaped connecting portions 71a to 74a, laser irradiation is performed on all the welded portions 80P and 80Q. And laser welding will be performed about welding part 80P and 80Q in the position which opposes circular arc-shaped connection part 71a-74a.

  Next, the connector terminals 81 to 84 and the assembly As are molded with a mold resin while being attached to the injector body 4. This mold resin becomes the connector housing 61 described above. Thus, the attachment of the fuel pressure sensor 50 and the like to the injector body 4 and the internal electrical connection are completed.

  Here, when the stem 51 is screwed to the injector body 4 by rotating the assembly As, the rotational position of the stem 51 is not fixed at a specific position when the screw fastening is completed. This means that the rotational positions of the sensor terminals 54b to 54e of the mold IC constituting the assembly As are also unspecified when the screw fastening of the stem 51 is completed.

  On the other hand, according to the present embodiment described in detail above, arc-shaped connection portions 71 a to 74 a extending in an arc shape around the rotation center of the stem 51 are formed on the electrodes 71 to 74. On the other hand, in each of the connector terminals 81 to 84, two welded portions 80P and 80Q are formed, and the interval L1 between the two welded portions 80P and 80Q is larger than the interval L2 between the arc ends of the arc-shaped connecting portions 71a to 74a. Set longer.

  Therefore, although the rotational direction positions of the sensor terminals 54b to 54e at the time when the screw fastening is completed are unspecified, at least one of the two welded portions 80P and 80Q is opposed to the arc-shaped connecting portions 71a to 74a. Will be located. As described above, the sensor terminals 54b to 54e whose rotational direction positions are unspecified and the connector terminals 81 to 84 arranged at the specified positions can be easily electrically connected via the electrodes 71 to 74.

  Furthermore, according to this embodiment, the following effects are also exhibited.

  Each of the arc-shaped connecting portions 71a to 74a of the electrodes 71 to 74 is arranged side by side in the direction of the rotation center of the stem 51 and arranged on the same plane, and a plurality of connector terminals 81 to 84 are also arranged in the direction of the rotation center. Arrange them side by side and arrange them on the same plane. Therefore, interference between adjacent electrical connection paths can be easily avoided.

  -Since the portions (arc-shaped connecting portions 71a-74a) connected to the welded portions 80P, 80Q of the electrodes 71-74 are formed in an arc shape, the electrodes 71-74 are developed in a plane on the metal plate as the base material. The electrode can be formed by press molding. Therefore, the electrodes 71 to 74 can be easily formed.

  Since the arc-shaped connecting portions 71a to 74a of the electrodes 71 to 74 are arranged on the same plane, the physique of the electrodes 71 to 74 in the rotational radial direction of the stem 51 can be reduced, and as a result, the physique of the injector in the rotational radial direction Can be downsized.

  The drive connector terminal 62 and the sensor connector terminals 81 to 84 are held in the same connector housing 61, whereby both terminals 62, 81 to 84 are configured as a common connector 60. Therefore, the fuel pressure sensor 50 can be mounted on the injector without increasing the number of connectors, and a harness for connecting an external device such as an engine ECU and the connector is gathered from one connector 60 provided on the injector body 4. It will be extended. Therefore, the handling of the harness can be simplified. Further, it is possible to avoid an increase in labor for connector connection work.

(Second Embodiment)
4A and 4B are diagrams showing the electrodes 71 to 74 according to the present embodiment, wherein FIG. 4A is a top view and FIG. 4B is a cross-sectional view taken along line AA of FIG. In the present embodiment, the plurality of electrodes 71 to 74 are integrated by primary molding with a molding resin 70m.

  More specifically, the mold resin 70m is formed in a cylindrical shape, and the connection surfaces of the arc-shaped connection portions 71a to 74a are exposed from the outer peripheral surface of the mold resin 70m. Further, portions of the extending portions 71b to 74b that are connected to the sensor terminals 54b to 54e are exposed from the mold resin 70m.

  Each of the arc-shaped connection portions 71 a to 74 a is formed with a plurality of groove portions 75 that are recessed inward in the radial direction from the connection surfaces with the connector terminals 81 to 84, and the mold resin 70 m flows into the groove portions 75. The electrodes 71 to 74 are molded so as to be in a state. In addition, the structure of the injector concerning this embodiment is the same as the said 1st Embodiment except the said primary mold being made | formed and the groove part 75 being formed.

  As described above, according to the present embodiment, since the electrodes 71 to 74 can be welded to the sensor terminals 54b to 54e in a state of being primary molded with the mold resin 70m, the workability of the welding can be improved.

  Each of the arc-shaped connection portions 71a to 74a is formed with a plurality of groove portions 75 that are recessed from the connection surface, and the electrodes 71 to 74 are molded so that the mold resin 70m flows into the groove portions 75. To do. Therefore, it is possible to suppress the arcuate connection portions 71a to 74a from being lifted and removed from the mold resin 70m in the radial direction.

(Third embodiment)
In the first embodiment, the first extending portions 81b to 84b and the second extending portions 81c to 84c forming the two welded portions 80P and 80Q are linearly formed in the tangential direction of the arc-shaped connecting portions 71a to 74a. It is formed in an extending shape. On the other hand, in the present embodiment shown in FIG. 5A, the first and second extending portions 81b to 84b and 81c to 84c are changed to arc-shaped extending portions 81d. Two welded portions 81P and 81Q are formed in each of the protruding portions 81d.

  Moreover, in order to concentrate the energy of a laser on the welding parts 81P and 81Q, the welding parts 81P and 81Q are formed in the shape (for example, hemispherical shape) protruded toward the circular arc-shaped connection parts 71a-74a. And the space | interval L3 of the two welding parts 81P and 81Q is set longer than the space | interval L2 of the circular arc both ends of the circular arc-shaped connection parts 71a-74a. Accordingly, at least one of the two welded portions 81P and 81Q is positioned so as to face the arcuate connection portions 71a to 74a.

  Or as shown in FIG.5 (b), you may form several welding part 80R in the outer peripheral surface of circular arc-shaped connection part 71a-74a at equal intervals. These welded portions 80R are formed in a shape (for example, a hemispherical shape) protruding toward the inner surface of the arc-shaped extending portion 81d. In this case, the arc length L5 of the arc-shaped connecting portions 71a to 74a is set longer than the interval L4 between the adjacent welded portions 80R. As a result, at least one of the plurality of welds 80R is positioned to face the inner surface of the arcuate extension 81d.

  As described above, also in the present embodiment shown in FIG. 5A or 5B, the sensor terminals 54b to 54e whose rotational direction positions are unspecified and the connector terminals 81 to 84 arranged at the specified positions are Electrical connection can be easily made through the electrodes 71 to 74.

( Reference example )
In the said 1st Embodiment, while the part (arc-shaped connection part 71a-74a) connected to welding part 80P, 80Q among the electrodes 71-74 is formed in circular arc shape, this reference example shown in FIG. Then, the part (annular connection part 71c, 72c, 73c, 74c) connected to the welding part 80P among the electrodes 71-74 is formed in the shape extended circularly around the rotation center of the stem 51. As shown in FIG.

In the first embodiment, the first extending portions 81b to 84b and the second extending portions 81c to 84c are formed on the connector terminals 81 to 84, so that one of the two welded portions 80P and 80Q has an arc shape. Even if it does not oppose connection part 71a-74a, the other opposes arcuate connection part 71a-74a, and welding is enabled. On the other hand, in this reference example , since the circular connection portions 71c to 74c are used instead of the arc-shaped connection portions 71a to 74a, the welding portion 80P can always be welded so as to face the circular connection portions 71c to 74c. Therefore, one weld 80P is sufficient. Therefore, the 2nd extension parts 81c-84c which were required in the said 1st Embodiment are abolished.

According to the reference example having the above-described configuration, the annular connection portions 71 c to 74 c extending in an annular shape around the rotation center of the stem 51 are formed in the electrodes 71 to 74. Therefore, regardless of the rotational direction positions of the sensor terminals 54b to 54e, the welded portions 80P of the connector terminals 81 to 84 are positioned so as to face the annular connection portions 71c to 74c. Therefore, the sensor terminals 54b to 54e whose rotational direction positions are unspecified and the connector terminals 81 to 84 arranged at the specified positions can be easily electrically connected via the electrodes 71 to 74.

  Further, each of the annular connection portions 71c to 74c included in the electrodes 71 to 74 is arranged side by side in the rotation center direction of the stem 51 and arranged on the same plane, and the first extension of the connector terminals 81 to 84 is performed. A plurality of parts 81b to 84b are also arranged side by side in the rotation center direction and arranged on the same plane. Therefore, interference between adjacent electrical connection paths can be easily avoided.

( Fourth embodiment)
In the first embodiment, the mold IC 54 is positioned below (injection hole side) the arc-shaped connection portions 71a to 74a, whereas in the present embodiment shown in FIG. 7, the arc-shaped connection portions 71a to 74a The case 56 (that is, the mold IC 54 and the strain gauge 52) is positioned inside the arc. Thereby, since the space inside the circular arc of the circular arc connecting portions 71a to 74a can be effectively used as the arrangement space for the mold IC 54, the strain gauge 52, etc., the physique in the axial direction of the injector can be reduced in size.

(Other embodiments)
The present invention is not limited to the description of the above embodiment, and may be modified as follows. Moreover, you may make it combine the characteristic structure of each embodiment arbitrarily, respectively.

In the second embodiment, the arc-shaped connecting portions 71a to 74a according to the first embodiment are primarily molded with the mold resin 70m. However, the arc-shaped extending portion 81d according to the third embodiment and the reference example are applied. The annular connection portions 71c to 74c may be primarily molded with a molding resin 70m.

  In each of the above embodiments, the stem 51 is screwed to the injector body 4 with the electrodes 71 to 74 connected to the sensor terminals 54b to 54e, and after the screw is fastened, the arc-shaped connecting portions 71a to 74a or the annular connecting portion 71c. To 74c are connected to the connector terminals 81 to 84. On the other hand, the stem 51 is screw-fastened in a state where the electrodes 71 to 74 are not connected to the sensor terminals 54b to 54e, and the arc-like connection portions 71a to 74a or the annular connection portions 71c to 74c are connected to the sensor terminals after the screw fastening. You may comprise so that it may connect to 54b-54e.

  In the first embodiment, the sensor terminals 54b to 54e and the electrodes 71 to 74 are molded separately (for example, press molding), but the sensor terminals 54b to 54e and the electrodes 71 to 74 are molded integrally (for example, Press forming).

  In each of the above embodiments, the present invention is applied to an injector configured to form the high pressure port 43 on the outer peripheral surface side of the injector body 4 and supply high pressure fuel from the outer peripheral surface side. The high-pressure port 43 may be formed on the side of the anti-injection hole in the axial direction, and the high-pressure fuel may be supplied from the side of the anti-injection hole.

  In each of the above embodiments, the drive connector terminal 62 and the sensor connector terminals 81 to 84 are held in the same connector housing 61 so that the terminals 62 and 81 to 84 are configured as the common connector 60. The drive connector terminal 62 and the sensor connector terminals 81 to 84 may be held in separate connector housings to constitute separate connectors.

  In each of the above embodiments, the screw portion 51 d is formed on the stem 51 and the stem 51 is screwed to the body 4. On the other hand, for example, a screw portion may be formed on the plate 53 or the case 56 and the body 4 may be screwed.

  In each of the above embodiments, the strain gauge 52 is employed as a sensor element that detects the strain amount of the stem 51, but other sensor elements such as a piezoelectric element may be employed.

  In each of the above embodiments, the present invention is applied to an injector of a diesel engine. However, the present invention may be applied to a gasoline engine, particularly, a direct injection gasoline engine that directly injects fuel into the combustion chamber E1.

  2 ... Electric actuator (driving means), 4 ... Injector body (body), 6 ... High pressure passage, 50 ... Fuel pressure sensor, 51c ... Diaphragm part, 51d ... Screw part, 52 ... Strain gauge (sensor element), 70m ... Mold resin 54b to 54e ... sensor terminals, 61 ... connector housing, 62 ... drive connector terminals (drive terminals), 81-84 ... sensor connector terminals (connector terminals), 71-74 ... electrodes, 71a-74a ... arc connection Part, 71c-74c ... annular connection part, 80P, 80Q, 81P, 81Q ... welding part.

Claims (6)

In a fuel injection valve mounted on an internal combustion engine and injecting fuel from a nozzle hole,
A body that internally forms a high-pressure passage through which high-pressure fuel flows to the nozzle hole;
A fuel pressure sensor attached to the body for detecting the pressure of the high-pressure fuel;
A plurality of sensor terminals provided at the fuel pressure sensor and including at least a terminal for outputting a detection signal of the fuel pressure sensor;
A plurality of connector terminals held in a connector housing attached to the body;
A plurality of electrodes that electrically connect each of the connector terminal and the sensor terminal;
With
The fuel pressure sensor has a screw part that is screwed to the body, and is configured to rotate together with the sensor terminal when the screw part is fastened.
The plurality of electrodes have an arcuate connection portion that is formed in an arc shape around the rotation center of the fuel pressure sensor and is electrically connected to either the connector terminal or the sensor terminal,
A fuel injection valve, wherein each of the arc-shaped connecting portions is arranged in a plurality of layers in a layered manner along the rotation center direction of the fuel pressure sensor. The connector terminal is formed with at least two welds that can come into contact with the arcuate connection part,
The fuel pressure sensor is configured to rotate together with the electrode electrically connected to the sensor terminal to be screwed.
2. The fuel injection valve according to claim 1, wherein an interval between the two welded portions is set to be longer than an interval between arc ends of the arc-shaped connecting portion. The electrode is molded with a mold resin in a state where the connection surface of the connection portion is exposed,
The electrode is formed with a groove having a shape recessed from the connection surface,
The fuel injection valve according to claim 1 or 2 , wherein the electrode is molded so that the mold resin flows into the groove. Each connecting surface of the connecting portion, the fuel injection valve according to any one of claims 1-3, characterized in that it is arranged on the same plane. A driving means for driving a needle for opening and closing the high-pressure passage, and a driving terminal for supplying power to the driving means,
The fuel injection valve according to any one of claims 1 to 4 , wherein the connector terminal and the drive terminal are configured as a common connector by holding the drive terminal in the connector housing. An internal electrical connection method for a fuel injection valve according to any one of claims 1 to 5 ,
A sensor terminal connection step of electrically connecting the electrode to the sensor terminal;
After the sensor terminal connecting step, the fuel pressure sensor is rotated together with the sensor terminal and the electrode, and a fastening step of screwing the fuel pressure sensor to the body;
After the fastening step, a connector terminal connecting step of electrically connecting the connector terminal to the connecting portion of the electrode;
An internal electrical connection method for a fuel injection valve, comprising:

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