JP7110384B2 - Fuel pump - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle component, and more particularly to a fuel pump that pressurizes fuel and supplies it to an engine.

2. Description of the Related Art High-pressure fuel supply pumps for pressurizing fuel are widely used in direct-injection engines that directly inject fuel into combustion chambers of automobile engines (internal combustion engines). As a conventional technology of this high-pressure fuel supply pump, for example, there is one disclosed in Japanese Patent Application Laid-Open No. 2018-087548 (Patent Document 1). In this patent document 1, "a high-pressure valve mechanism 300 having an intake valve 30 for opening and closing the flow path on the upstream side of the pressurizing chamber 11 and an electromagnetic coil 43 for controlling the opening and closing of the intake valve 30 is provided. In the fuel supply pump, a groove 39c formed in the intake valve mechanism 300; ,” (see abstract).

JP 2018-087548 A

Since the fuel pump is mounted in a narrow space inside the engine, it is desirable that it be as small as possible. The intake valve mechanism 300 is inserted into the pump body from the outside in the radial direction, and is a mechanism that protrudes radially outside the pump body. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to reduce the size of a fuel pump by shortening the axial length of an electromagnetic suction valve mechanism.

In order to solve the above-described problems, the fuel pump of the present invention is arranged in a fixed core that attracts a movable core by a magnetic attraction force generated by energizing a coil, and a recess formed on the inner diameter side of the fixed core. a rod driven by the movable core and a spring member for urging; a magnetic member arranged axially outside the core and forming a magnetic circuit ; a terminal member for power supply disposed along a radial direction intersecting the axial direction and electrically connected to the coil, wherein the bottom surface of the recessed portion of the fixed core is axially outward of the magnetic member. The axially outer spring end surface of the spring member is arranged axially outwardly of the axially outer end surface of the magnetic member, and the terminal member is arranged axially outwardly of the axially outer end surface of the magnetic member. and the axially inner end surface .

According to the present invention constructed in this way, it is possible to reduce the length of the electromagnetic intake valve mechanism, particularly in the axial direction, and to reduce the size of the fuel pump. Configurations, functions, and effects of the present invention other than those described above will be described in detail in the following examples.

The block diagram of the engine system to which the fuel pump was applied is shown. It is a longitudinal cross-sectional view of a fuel pump. FIG. 4 is a horizontal cross-sectional view of the fuel pump as seen from above; FIG. 3 is a vertical cross-sectional view of the fuel pump as seen from a direction different from that in FIG. 2 ; 3 is an axial cross-sectional view for explaining the electromagnetic suction valve mechanism 3 of the embodiment of the present invention; FIG. Fig. 3 is an enlarged view of the electromagnetic intake valve mechanism 3 of the embodiment of the present invention; Fig. 3 is an exploded view showing the main parts of the electromagnetic suction valve mechanism 3 of the embodiment of the present invention;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

First, an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 7. FIG. The configuration and operation of the system will be described with reference to the overall configuration diagram of the engine system shown in FIG. A portion surrounded by a dashed line indicates the main body of a high-pressure fuel supply pump (hereinafter referred to as a fuel pump), and mechanisms and parts indicated within the dashed line are integrated with a body 1 (which may also be referred to as a pump body). Indicates built-in.

Fuel in a fuel tank 103 is pumped up from the fuel tank 103 by a feed pump 102 based on a signal from an engine control unit 101 (hereinafter referred to as ECU). This fuel is pressurized to a suitable feed pressure and sent through a fuel line 104 to the low pressure fuel inlet 10a of the fuel pump.

The fuel flowing from the low-pressure fuel inlet 10a of the suction pipe 5 (not shown in FIG. 1) passes through the pressure pulsation reduction mechanism 9 and the suction passage 10d and reaches the suction port 3k of the electromagnetic suction valve mechanism 3, which is a variable displacement mechanism. .

The fuel that has flowed into the electromagnetic intake valve mechanism 3 passes through the intake valve 3b, flows through the intake passage 1a formed in the body 1, and then flows into the pressurization chamber 11. As shown in FIG. Power for reciprocating motion is given to the plunger 2 by the cam mechanism 91 of the engine. Due to the reciprocating motion of the plunger 2, fuel is sucked from the intake valve 3b during the downward stroke of the plunger 2, and the fuel is pressurized during the upward stroke. When the pressure in the pressurization chamber 11 exceeds a set value, the discharge valve mechanism 8 is opened, and high pressure fuel is pressure-fed to the common rail 106 on which the pressure sensor 105 is mounted. Then, based on a signal from the ECU 101, the injector 107 injects fuel into the engine. This embodiment is a fuel pump applied to a so-called direct injection engine system in which an injector 107 directly injects fuel into a cylinder of an engine. The fuel pump discharges a desired flow rate of supplied fuel according to a signal from the ECU 101 to the electromagnetic intake valve mechanism 3 .

FIG. 2 shows a vertical cross-sectional view of the fuel pump of this embodiment, and FIG. 3 is a horizontal cross-sectional view of the fuel pump viewed from above. FIG. 4 is a longitudinal sectional view of the fuel pump as viewed in a vertical section different from that of FIG. The fuel pump of this embodiment is tightly attached to a fuel pump mounting portion 90 (FIGS. 2 and 4) of an engine (internal combustion engine) using a mounting flange 1e (FIG. 3) provided on the body 1, and fixed with a plurality of bolts (not shown). be done.

As shown in FIGS. 2 and 4, an O-ring 93 is fitted into the body 1 for sealing between the fuel pump mounting portion 90 and the body 1 to prevent engine oil from leaking to the outside. A cylinder 6 that guides the reciprocating motion of the plunger 2 and forms a pressure chamber 11 together with the body 1 is attached to the body 1 . Also provided are an electromagnetic intake valve mechanism 3 for supplying fuel to the pressurizing chamber 11 and a discharge valve mechanism 8 for discharging fuel from the pressurizing chamber 11 to the discharge passage.

The cylinder 6 is press-fitted with the body 1 on its outer peripheral side. Further, by deforming the body 1 to the inner peripheral side (inward in the radial direction), the fixing portion 6a of the cylinder 6 is pressed upward in the drawing, and the fuel pressurized in the pressure chamber 11 at the upper end surface of the cylinder 6 is released. It is sealed to prevent leakage to the low pressure side. That is, the pressurization chamber 11 is composed of the body 1 , the electromagnetic intake valve mechanism 3 , the plunger 2 , the cylinder 6 and the discharge valve mechanism 8 .

A tappet 92 is provided at the lower end of the plunger 2 to convert the rotary motion of a cam 91 attached to the camshaft of the engine into vertical motion and transmit the vertical motion to the plunger 2 . The plunger 2 is pressed against the tappet 92 by the spring 18 via the retainer 15 . As a result, the plunger 2 can be reciprocated up and down as the cam 91 rotates.

A plunger seal 13 held at the lower end portion of the inner periphery of the seal holder 7 is installed in a state of slidably contacting the outer periphery of the plunger 2 at the lower portion of the cylinder 6 in the drawing. As a result, when the plunger 2 slides, the fuel in the auxiliary chamber 7a is sealed and prevented from flowing into the engine. At the same time, it prevents lubricating oil (including engine oil) for lubricating sliding parts in the engine from flowing into the interior of the body 1 .

The relief valve mechanism 4 shown in FIGS. 2 and 3 is composed of a seat member 4e, a relief valve 4d, a relief valve holder 4c, a relief spring 4b, and a spring support member 4a. The spring support member 4a also functions as a relief body that encloses the relief spring 4b and forms a relief valve chamber. A spring support member 4a (relief body) of the relief valve mechanism 4 is press-fitted into a horizontal hole formed in the body 1 and fixed. One end of the relief spring 4b contacts the spring support member 4a, and the other end contacts the relief valve holder 4c. The relief valve 4d cuts off the fuel when the relief valve seat (seat member 4e) is pressed against the relief valve seat (seat member 4e) by the biasing force of the relief spring 4b acting through the relief valve holder 4c. The opening pressure of the relief valve 4d is determined by the biasing force of the relief spring 4b. In this embodiment, the relief valve mechanism 4 communicates with the pressure chamber 11 via the relief passage, but is not limited to this, and communicates with the low pressure passage (low pressure fuel chamber 10, intake passage 10d, etc.). You can make it work. The relief valve mechanism 4 is a valve configured to operate when some problem occurs in the common rail 106 or a member therebehind and the common rail 106 becomes abnormally high pressure.

That is, the relief valve mechanism 4 is configured such that the relief valve 4d opens against the biasing force of the relief spring 4b when the differential pressure between the upstream side and the downstream side of the relief valve 4d exceeds the set pressure. be. When the pressure in the common rail 106 and its members increases, the valve opens to return the fuel to the pressurization chamber 11 or the low pressure passage (low pressure fuel chamber 10 or intake passage 10d, etc.). 2 and 3 show a structure in which the relief valve mechanism 4 returns to the pressure chamber 11 when the valve is opened. Therefore, it is necessary to maintain the valve closed state below a predetermined pressure, and has a very strong relief spring 4b to resist the high pressure.

As shown in FIGS. 3 and 4, a suction pipe 5 is attached to the side surface of the body 1 . The intake pipe 5 is connected to a low-pressure pipe 104 for supplying fuel from a fuel tank 103 of the vehicle, and the fuel is supplied from here to the interior of the fuel pump. A suction filter 17 in the suction flow path 5a at the tip of the suction pipe 5 prevents foreign matter existing between the fuel tank 103 and the low-pressure fuel suction port 10a from being absorbed into the fuel pump by the flow of fuel. The fuel that has passed through the low pressure fuel inlet 10a reaches the suction port 3k of the electromagnetic suction valve mechanism 3 via the pressure pulsation reduction mechanism 9 and the low pressure fuel passage 10d (see FIG. 2).

In the intake stroke in which the plunger 2 moves in the direction of the cam 91 due to the rotation of the cam 91, the volume of the pressurizing chamber 11 increases and the fuel pressure in the pressurizing chamber 11 decreases. In the suction stroke, the electromagnetic coil 3g is in a non-energized state, and the rod 3i is urged in the valve opening direction (rightward direction in FIGS. 3 and 4) by the rod urging spring 3, so that the tip of the rod 3i moves the movable core Activate 3h. In this stroke, when the fuel pressure in the pressurizing chamber 11 becomes lower than the pressure in the intake port 3k and the biasing force of the rod biasing spring 3 becomes greater than the differential pressure across the intake valve 3b, the intake valve 3b closes to the intake valve. It leaves the seat portion 3a and becomes an open valve state. As a result, the fuel flows into the pressure chamber 11 through the opening 3f of the intake valve 3b. The rod 3i biased by the rod biasing spring 3 collides with the stopper 3n and is restricted from moving in the valve opening direction.

After the plunger 2 completes the suction stroke, the plunger 2 turns to ascending motion and shifts to the ascending stroke. Here, the electromagnetic coil 3g remains in a non-energized state and no magnetic biasing force acts. The rod biasing spring 3m is set to have a necessary and sufficient biasing force to keep the intake valve 3b open in a non-energized state. The volume of the pressurization chamber 11 decreases as the plunger 2 compresses, but in this state, the fuel once sucked into the pressurization chamber 11 is again sucked through the opening 3f of the intake valve 3b in the open state. Since it is returned to the passage 10d, the pressure in the pressurizing chamber does not rise. This stroke is called a return stroke.

In this state, when a control signal from the engine control unit 101 (hereinafter referred to as ECU) is applied to the electromagnetic intake valve mechanism 3, current flows through the electromagnetic coil 3g via the terminal 16. FIG. When a current flows through the electromagnetic coil 3g, a magnetic attraction force acts between the fixed core 3e (magnetic core) and the movable core 3h, and the fixed core 3e and the movable core 3h come into contact with each other at the magnetic attraction surface. The magnetic attraction force overcomes the biasing force of the rod biasing spring 3m to bias the movable core 3h, and the movable core 3h engages with the rod protrusion 3j to move the rod 3i away from the intake valve 3b.

Therefore, the intake valve 3b is closed by the fluid force caused by the urging force of the intake valve urging spring 3l and the fuel flowing into the intake passage 10d. After the valve is closed, the fuel pressure in the pressurizing chamber 11 rises with the upward motion of the plunger 2, and when it reaches or exceeds the pressure at the fuel discharge port 12a, high pressure fuel is discharged through the discharge valve mechanism 8 to the common rail 106. supplied. This stroke is called a discharge stroke. A discharge joint 12 is inserted into the lateral hole of the body 1, and the internal space of the discharge joint 12 forms a fuel discharge port 12a. The discharge joint 12 is fixed to the lateral hole of the body 1 by welding with a welded portion 12b.

That is, the upward stroke from the lower start point to the upper start point of the plunger 2 consists of a return stroke and a discharge stroke. By controlling the timing of energization of the coil 3g of the electromagnetic intake valve mechanism 3, the amount of high-pressure fuel to be discharged can be controlled. If the timing of energizing the electromagnetic coil 3g is advanced, the proportion of the return stroke in the upward stroke is small and the proportion of the discharge stroke is large. That is, less fuel is returned to the intake passage 10d, and more fuel is discharged at high pressure. On the other hand, if the timing of energization is delayed, the proportion of the return stroke in the ascending stroke is large and the proportion of the discharge stroke is small. That is, more fuel is returned to the intake passage 10d, and less fuel is discharged at high pressure. The timing of energization of the electromagnetic coil 3g is controlled by a command from the ECU 101. FIG.

By controlling the timing of energization of the electromagnetic coil 3g as described above, the amount of fuel discharged at high pressure can be controlled to the amount required by the engine. The discharge valve mechanism 8 on the outlet side of the pressurizing chamber 11 of the body 1 includes a discharge valve seat 8a, a discharge valve 8b that contacts and separates from the discharge valve seat 8a, and a discharge valve spring that biases the discharge valve 8b toward the discharge valve seat 8a. 8c, and a discharge valve stopper 8d that determines the stroke (movement distance) of the discharge valve 8b. The discharge valve stopper 8d is press-fitted into a plug 8e for blocking leakage of fuel to the outside. The plug 8e is joined by welding at the welded portion 8f. A discharge valve chamber 8g is formed on the secondary side of the discharge valve 8b, and the discharge valve chamber 8g communicates with the fuel discharge port 12a through a lateral hole formed in the body 1 in the horizontal direction.

When there is no fuel differential pressure between the pressure chamber 11 and the discharge valve chamber 8g, the discharge valve 8b is pressed against the discharge valve seat 8a by the biasing force of the discharge valve spring 8c and closed. Only when the fuel pressure in the pressure chamber 11 becomes higher than the fuel pressure in the discharge valve chamber 8g does the discharge valve 8b open against the biasing force of the discharge valve spring 8c. When the discharge valve 8b is opened, the high-pressure fuel in the pressure chamber 11 is discharged to the common rail 106 (see FIG. 1) through the discharge valve chamber 8g and the fuel discharge port 12a. With the configuration described above, the discharge valve mechanism 8 functions as a check valve that restricts the flow direction of the fuel.

A pressure pulsation reduction mechanism 9 is installed in the low-pressure fuel chamber 10 to reduce the pressure pulsation generated in the fuel pump from reaching the fuel pipe 104 . Once the fuel that has flowed into the pressurization chamber 11 is returned to the intake passage 10d through the intake valve body 3b in the open state again for capacity control, the fuel returned to the intake passage 10d causes the low-pressure fuel chamber 10 to Pressure pulsation occurs. However, the pressure pulsation reduction mechanism 9 provided in the low-pressure fuel chamber 10 is formed of a metal diaphragm damper in which two corrugated disk-shaped metal plates are pasted together at their outer circumferences and an inert gas such as argon is injected inside. The pressure pulsation is absorbed and reduced by the expansion and contraction of this metal damper.

The plunger 2 has a large diameter portion 2a and a small diameter portion 2b, and the volume of the pre-chamber 7a increases and decreases as the plunger reciprocates. The auxiliary chamber 7a communicates with the low-pressure fuel chamber 10 through a fuel passage 10e. Fuel flows from the auxiliary chamber 7a to the low-pressure fuel chamber 10 when the plunger 2 is lowered, and from the low-pressure fuel chamber 10 to the auxiliary chamber 7a when the plunger 2 is raised. As a result, it is possible to reduce the flow rate of fuel into and out of the pump during the suction stroke or return stroke of the pump, and has the function of reducing the pressure pulsation that occurs inside the fuel pump.

The fuel pump of this embodiment will be specifically described below with reference to FIGS. FIG. 5 shows an axial sectional view of the electromagnetic suction valve mechanism 3 of this embodiment, FIG. 6 is an enlarged drawing of the electromagnetic suction valve mechanism 3, and FIG. It is a drawing shown in FIG. As shown in FIG. 5, the fuel pump of this embodiment includes a bobbin 3p arranged radially outward of a fixed core 3e or a movable core 3h, on which a coil 3g is wound, and a terminal member 16 corresponding to the notch 3ra. It is connected to the bobbin 3p at the position where it does. Specifically, the fuel pump includes a cup-shaped yoke 3q arranged radially outside the coil 3g and the cover member 3r, and the terminal member 16 is arranged radially inside the cylindrical side surface of the yoke 3q to provide a bobbin. 3p. The cover member 3r is biased inward in the axial direction by the disc spring 3s, and the C ring 3t is fitted in a groove formed in the small diameter portion 3ea of the fixed core 3e, thereby maintaining the biased state of the disc spring 3s. The disc spring 3s is held as shown.

As shown in FIG. 7, the bobbin 3p has a projecting portion 3pa arranged from the radially inner side to the radially outer side with respect to the cylindrical side portion of the yoke 3q, and the terminal member 16 is fixed by the projecting portion 3pa. The bobbin 3p and the projecting portion 3pa are integrally made of a non-conductive material such as resin mold or plastic. A hole 3qc is formed in the bottom surface of the yoke 3q, and the inner peripheral portion of the hole 3qc is press-fitted to the outer peripheral portion of the anchor guide portion 3u. The inner peripheral portion of the anchor guide portion 3u guides the outer peripheral portion of the anchor 3h. The inner peripheral portion of the anchor guide portion 3u is press-fitted to the outer peripheral portion of the small-diameter portion of the sheet member 3v on the side opposite to the anchor 3h in the axial direction. The seat member 3v forms the seat portion 3a shown in FIGS. 2 and 3, and has an elongated hole formed in the center in the radial direction. The rod 3i is guided by the inner peripheral portion of the elongated hole.

Also, the coil 3g is connected to the terminal member 16 on the radially outer side of the yoke 3q. Specifically, the terminal member 16 clamps the wire from the coil 3g at the wire connecting portion 16a and fixes the wire by crimping. That is, the wire from the coil 3g is welded to the terminal member 16 at the wire connecting portion 16a. Note that the wire from this coil 3g is not shown in FIG. The bobbin 3p has a projection 3pb or a groove (not shown) formed along the axial direction of the coil 3g (horizontal direction in FIG. 5), and the wire of the coil 3g contacts the projection 3pb or the groove. It is desirable that the terminal member 16 be formed so as to be wound around the terminal member 16 in this state. In addition, the bobbin 3p is formed with a notch 3pc for disposing the coil 3g wound on the bobbin 3p axially outside the coil 3g, and axially inside the notch 3pc of the bobbin 3p (rightward in FIG. 5). The coil 3g arranged axially outward (leftward in FIG. 5) is formed toward the projection 3pb or groove located radially outward.

Here, as shown in FIGS. 5 and 6, the fuel pump of this embodiment includes a fixed core 3e that attracts the movable core by a magnetic attraction force generated by energizing the coil 3g, and a magnetic member ( and a cover member 3r). The magnetic member is arranged axially outside the fixed core 3e. The spring member 3m is arranged in a recessed portion 3ec formed on the inner diameter side of the fixed core 3e and biases the rod 3i driven by the movable core 3h. An axially outer spring end face 3ma of the spring member 3m is arranged axially outside (left side in FIG. 5) of the axially outer end face (axially outer cover end face 3rc) of the magnetic member. Further, it is desirable that the bottom surface 3ed of the recessed portion 3ec of the fixed core 3e is arranged axially outside the axially outer end surface (axially outer cover end surface 3rc) of the magnetic member.

The magnetic member described above is the cover member 3r arranged axially outside of the fixed core 3e, and the axially outer cover end surface of the cover member 3r and the axially outer end surface of the magnetic member are flush with each other. . In this embodiment, the fixed core 3e is made of Fe and contains C 0.18 wt%, Mo, Si, Al 12 wt% or less, Cu 2 wt%, Ni 4 wt%, Cr 9-20 wt%, Ti 0.5 wt% or less. and other impurity elements, the hardness of which is adjusted to about Hmv 350-450.

5 and 6, the fixed core 3e and the magnetic member (cover member 3r) are configured as separate members, but the present invention is not limited to this, and they may be integrated members. That is, in this case, the large-diameter portion 3ea and the cover member 3r are formed as an integral member, and the axially outer end surface of the integrated large-diameter portion is the axially outer cover end surface 3rc of the cover member 3r. show. Thereby, it becomes possible to move the position of the spring member 3m to the outside in the axial direction as compared with the conventional art. Therefore, since the axial length of the fixed core 3e can be shortened, the cost can be reduced.

5 and 6, the fixed core 3e and the cover member 3r are separate members, but the cover member 3r is also a magnetic member. The axially outer cover end surface 3rc of the cover member 3r and the axially outer end surface of the fixed core 3e are flush with each other. As a result, the space of the hole formed in the central portion of the cover member 3r can be effectively utilized, and the axial length of the fixed core 3e can be shortened. In addition, since the cover member 3r comes closer to the coil 3g, the size of the magnetic circuit can be reduced, and as a result, the efficiency of the magnetic circuit can be improved.

FIG. 6 is an enlarged view of the electromagnetic intake valve mechanism 3. As shown in FIG. The fixed core 3e has a large diameter portion 3ea and a small diameter portion 3eb, and the cover member 3r is arranged radially outside the small diameter portion 3eb and axially outside the large diameter portion 3ea. The small diameter portion 3eb of the fixed core 3e has a length L1 from the axially outer cover end surface 3rc of the cover member 3r to the axially outer small diameter end surface 3ee of the small diameter portion 3eb. It is configured to be equal to or longer than the length L2 from the axially inner large diameter end surface 3ef of 3ea. The small-diameter portion 3eb of the fixed core 3e has a length L3 from the axially outer yoke end surface 3qa of the yoke 3q to the axially outer small-diameter end surface 3ee of the small-diameter portion 3eb. It is configured to be larger than the length L4 to the axial outer yoke end surface 3qa. That is, by securing the length of L3, it is possible to secure the strength for withstanding the load received from the spring member 3m.

A terminal member 16 for power supply is electrically connected to the coil 3 g and arranged inside the connector 17 . The fixed core 3 e is configured such that the axially outer small diameter end surface 3 ee of the small diameter portion 3 eb is arranged axially outward with respect to the axially outer connector end surface 17 b of the connector 17 . Further, the terminal member 16 is arranged inside the connector 17 and along a direction (vertical direction in FIG. 6) intersecting the axial direction (horizontal direction in FIG. 6) of the coil 3g, and is electrically connected to the coil 3g. connected to The spring member 3m is disposed radially inward of the cover member 3r, and the axially outer spring end surface 3ma of the spring member 3m is axially outward with respect to the connecting portion (wire connecting portion 16a) between the terminal member and the coil 3g. Arranged to be arranged. Thereby, the length of L3 can be secured, and the strength for withstanding the load received from the spring member 3m can be secured.

As shown in FIG. 7, the yoke 3q is formed in a cylindrical shape, and a notch 3qb extending axially inward from a portion of the axially outer end surface 3qa of the yoke 3q in the circumferential direction is formed. The terminal member 16 extends from the radially inner side of the yoke 3q to the radially outer side of the yoke 3q, passing through the notch 3qb. As a result, the terminal member 16 can be protruded in the radial direction, so that the length in the axial direction can be shortened compared to the case where the terminal member 16 is protruded in the axial direction. can be The connector 17 is formed such that the radial length L5 is greater than the axial length L6, and the axial length L6 is substantially constant over the entire longitudinal (radial) region of the connector 17. It is desirable to form

According to the configuration of the present embodiment as described above, it is possible to improve the attractive force by which the movable core 3h is magnetically attracted when the coil 3g is energized, and it is possible to reduce the size of the electromagnetic suction valve mechanism 3. . That is, according to this embodiment, the magnetic circuit can be efficiently formed, so that the necessary magnetic attractive force can be generated even if the applied current is reduced, and the power consumption can be reduced.

1 Body 2 Plunger 3 Electromagnetic Intake Valve Mechanism 4 Relief Valve Mechanism 5 Intake Pipe 5a Intake Pipe Mounting Portion 6 Cylinder 7 Seal Holder 8 Discharge Valve Mechanism 9 Pressure Pulsation Reduction Mechanism 10a Low Pressure Fuel Suction Port 11 Pressurization Chamber 12 Discharge Joint 13 Plunger Seal

Claims (8)

a fixed core that attracts the movable core by a magnetic attraction force generated by energizing the coil;
a spring member disposed in a recess formed on the inner diameter side of the fixed core and biasing the rod driven by the movable core;
a magnetic member disposed axially outside the fixed core and forming a magnetic circuit;
a terminal member for feeding that is arranged inside the connector and along a radial direction that intersects the axial direction of the coil and is electrically connected to the coil ;
The fixed core has a large diameter portion and a small diameter portion,
an axially outer connector end face of the connector is arranged axially inward with respect to an axially outer small diameter end face of the small diameter portion;
a bottom surface of the recessed portion of the fixed core is arranged axially outside an axially outer end surface of the magnetic member;
an axially outer spring end surface of the spring member is arranged axially outside an axially outer end surface of the magnetic member ;
In the fuel pump, the terminal member extends radially from a position including a range between the axially outer end surface and the axially inner end surface of the magnetic member . A fuel pump according to claim 1,
The magnetic member is a cover member arranged axially outside the fixed core,
The fuel pump, wherein the axially outer cover end surface of the cover member and the axially outer end surface of the magnetic member are flush with each other. A fuel pump according to claim 2 ,
The cover member is arranged radially outside the small diameter portion and axially outside the large diameter portion. A fuel pump according to claim 3 ,
The small-diameter portion of the fixed core has a length from the axially outer cover end surface of the cover member to the axially outer small-diameter end surface of the small-diameter portion, which is the axis of the large-diameter portion from the axially inner cover end surface of the cover member. A fuel pump configured to have a length equal to or greater than the length to the large-diameter end surface on the inner side. A fuel pump according to claim 3 ,
a yoke arranged radially outward of the coil and the cover member;
The small-diameter portion of the fixed core has a length from the axially outer yoke end surface of the yoke to the axially outer small-diameter end surface of the small-diameter portion from the axially outer cover end surface of the cover member to the axially outer side of the yoke. A fuel pump configured to be large with respect to the length to the yoke end surface. A fuel pump according to claim 2 ,
The spring member is arranged radially inside the cover member,
The fuel pump is arranged such that the axially outer spring end surface of the spring member is arranged axially outward with respect to the connecting portion between the terminal member and the coil. A fuel pump according to claim 6 ,
a yoke arranged radially outward of the coil and the cover member;
The yoke is formed in a cylindrical shape and has a notch extending axially inward from a portion of the axially outer end surface of the yoke in the circumferential direction,
The terminal member passes through the notch from the radially inner side of the yoke and extends radially outwardly of the yoke. A fuel pump according to claim 6 ,
The connector is formed such that its radial length is greater than its axial length, and the fuel pump is formed such that the radial length is substantially constant over the entire lengthwise region of the connector. .

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