JP6932629B2 - High pressure fuel pump - Google Patents

Description

The present invention relates to a high pressure fuel pump.

In the electromagnetic suction valve mechanism of a high-pressure fuel pump, a yoke is arranged around the electromagnetic coil to form a magnetic circuit. Such a yoke is fixed by press-fitting as an example (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2016-191367

In the technique disclosed in Patent Document 1, since it is necessary to strictly control the dimensions of the press-fitting portion, the manufacturing cost is remarkably increased. On the other hand, the inventor of the present application has found a method of fixing the yoke using a retaining ring.

On the other hand, in the retaining ring for a shaft or a hole, a retaining ring provided with a partial notch (slit) is widely used. These retaining rings are generally delivered in a stack form in which they are arranged in a rod shape and attached with tape, and the shape is not suitable for general parts supply equipment such as a parts feeder. In addition, the insertability of the retaining ring has not been sufficiently examined.

Here, in the case of a retaining ring having a slit formed, if the retaining ring is scattered like a bag, the retaining rings are entangled with each other from the slit and cannot be easily released. Delivery in the form of a stack is effective for this problem, but it causes a significant increase in cost. Further, regarding the insertability into the product, there is a lack of ingenuity in mounting the insertion guide jig and facilitating the insertability in the product itself.

An object of the present invention is to provide a high pressure fuel pump in which the yoke can be easily fixed by a retaining ring that does not get entangled or can be easily released from the entanglement.

In order to achieve the above object, the present invention has an anchor, a first surface that magnetically attracts the anchor, and a second surface opposite to the first surface, and the second surface. A fixed core having a convex portion, a yoke that is inserted through the convex portion and is in contact with the second surface, an elastic body that is inserted through the convex portion and urges the yoke, and is inserted through the convex portion. A high-pressure fuel pump comprising a retaining ring for fixing one end of the elastic body, wherein the retaining ring has a slit having a width larger than the maximum radial width of the retaining ring or smaller than the plate thickness of the retaining ring. The convex portion has a conical portion, a first groove portion on which the retaining ring and the elastic body are arranged, in the order from the tip of the convex portion to the root, and the diameter of the first groove portion. Is larger than the minimum diameter of the conical portion and smaller than the maximum diameter of the conical portion .

According to the present invention, the yoke can be easily fixed by a retaining ring that does not get entangled or can be easily released from the entanglement. Issues, configurations and effects other than those described above will be clarified by the description of the following embodiments.

FIG. 5 is an overall cross-sectional view showing the high-pressure fuel pump according to the embodiment of the present invention cut in the axial direction of the plunger. The high-pressure fuel pump of the embodiment of the present invention is an overall cross-sectional view shown by cutting in a direction perpendicular to the axial direction of the plunger, and is a cross-sectional view at the center of the intake port shaft and the center of the discharge port shaft of the fuel. It is an overall cross-sectional view of the high pressure fuel pump of the embodiment of the present invention at an angle different from FIG. 1, and is a cross-sectional view at the center of the suction joint shaft. It is an enlarged view of the vertical sectional view of the electromagnetic suction valve mechanism of the high pressure fuel pump of the embodiment of this invention. It is a figure which shows the whole structure of the system including the high pressure fuel pump of embodiment of this invention. It is an enlarged vertical sectional view of the structure in the vicinity of the solenoid valve mechanism part surrounded by the round frame A of FIG. It is a vertical cross-sectional view which shows the example of changing the shape of the member constituting the fixed core of FIG. 6 by enlarging the solenoid valve mechanism part surrounded by the round frame A of FIG. It is a vertical cross-sectional view which enlarges and shows the vicinity of a part of the fixed core surrounded by the broken line B of FIG. FIG. 5 is an enlarged vertical cross-sectional view showing a part of the vicinity of the fixed core surrounded by the broken line B in FIG. 7. It is a perspective view of the member which constitutes a retaining ring. It is an arrow view from the Z1 direction of FIG. 9 about the member constituting a retaining ring. It is a perspective view of the example of changing the shape of the member constituting a retaining ring. It is an arrow view from the Z2 direction of FIG. 11 about the member constituting a retaining ring.

Hereinafter, the configuration of the high-pressure fuel pump (high-pressure fuel supply pump) according to the embodiment of the present invention will be described with reference to the drawings. In each figure, the same reference numerals indicate the same parts.

(Embodiment 1)
First, the configuration and operation of the system will be described with reference to the overall configuration diagram of the engine system shown in FIG. The part surrounded by the broken line indicates the main body of the high-pressure fuel pump, and the mechanism / component shown in the broken line indicates that the pump body 1 (pump housing) is integrally incorporated.

The fuel in the fuel tank 20 is pumped by the feed pump 21 based on a signal from the engine control unit 27 (hereinafter referred to as an ECU). This fuel is pressurized to an appropriate feed pressure and sent to the low pressure fuel suction port 10a of the high pressure fuel pump through the suction pipe 28.

The fuel that has passed through the suction joint 51 (see FIG. 2) from the low-pressure fuel suction port 10a passes through the metal damper 9 (pressure pulsation reduction mechanism) and the suction passage 10d, and the suction port 31b of the electromagnetic suction valve mechanism 300 that constitutes the capacity variable mechanism. To.

The fuel that has flowed into the electromagnetic suction valve mechanism 300 passes through the suction valve 30 and flows into the pressurizing chamber 11. The cam 93 (see FIG. 1) of the engine (internal combustion engine) gives the plunger 2 the power to reciprocate. Due to the reciprocating motion of the plunger 2, fuel is sucked from the suction valve 30 in the descending stroke of the plunger 2, and the fuel is pressurized in the ascending stroke. Fuel is pumped to the common rail 23 on which the pressure sensor 26 is mounted via the discharge valve mechanism 8. Then, the injector 24 injects fuel into the engine based on the signal from the ECU 27. This embodiment is a high-pressure fuel pump applied to a so-called direct injection engine system in which the injector 24 injects fuel directly into the cylinder cylinder of the engine.

The high-pressure fuel pump discharges a desired fuel flow rate of the supplied fuel by a signal from the ECU 27 to the electromagnetic suction valve mechanism 300.

Next, the configuration of the high-pressure fuel pump will be described with reference to FIGS. 1 to 4. FIG. 1 shows a vertical cross-sectional view of the high-pressure fuel pump, and FIG. 2 is a horizontal cross-sectional view of the high-pressure fuel pump as viewed from above. Further, FIG. 3 is a vertical sectional view of the high-pressure fuel pump viewed from a direction different from that of FIG. FIG. 4 is an enlarged view of the electromagnetic suction valve mechanism 300.

As shown in FIG. 1, the high-pressure fuel pump is attached to a metal damper 9, a pump body 1 (pump body) in which a damper accommodating portion 1p accommodating the metal damper 9 is formed, and a damper accommodating portion. A damper cover 14 (housing cover) that covers 1p and holds the metal damper 9 between the pump body 1 and a holding member 9a that is fixed to the damper cover 14 and holds the metal damper 9 from the opposite side to the damper cover 14. , Is equipped. The holding member 9a is arranged between the metal damper 9 and the pump body 1, and holds the metal damper 9 from the side of the pump body 1.

The high-pressure fuel pump is brought into close contact with the high-pressure fuel pump mounting portion 90 of the internal combustion engine using a mounting flange 1e (see FIG. 2) provided on the pump body 1 and fixed with a plurality of bolts.

As shown in FIG. 1, an O-ring 61 is fitted into the pump body 1 for a seal between the high-pressure fuel pump mounting portion 90 and the pump 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 pressurizing chamber 11 together with the pump body 1 is attached to the pump body 1. Further, an electromagnetic suction valve mechanism 300 for supplying fuel to the pressurizing chamber 11 and a discharge valve mechanism 8 (see FIG. 2) for discharging fuel from the pressurizing chamber 11 into the discharge passage are provided.

As shown in FIG. 1, the cylinder 6 is press-fitted into the pump body 1 on the outer peripheral side thereof, and further, at the fixing portion 6a, the body is deformed to the inner peripheral side to press the cylinder 6 upward in the drawing, and the cylinder 6 is pressed. The fuel pressurized in the pressurizing chamber 11 is sealed on the upper end surface of the cylinder so as not to leak to the low pressure side.

At the lower end of the plunger 2, a tappet 92 is provided that converts the rotational motion of the cam 93 (cam mechanism) attached to the camshaft of the internal combustion engine into vertical motion and transmits it to the plunger 2. The plunger 2 is crimped to the tappet 92 by a spring 4 via a retainer 15. As a result, the plunger 2 can be reciprocated up and down with the rotational movement of the cam 93.

Further, the plunger seal 13 held at the lower end of the inner circumference of the seal holder 7 is installed in a slidable contact with the outer periphery of the plunger 2 at the lower portion in the drawing of the cylinder 6. As a result, when the plunger 2 slides, the fuel in the sub chamber 7a is sealed and prevented from flowing into the internal combustion engine. At the same time, it prevents the lubricating oil (including the engine oil) that lubricates the sliding portion in the internal combustion engine from flowing into the pump body 1.

A suction joint 51 is attached to the side surface of the pump body 1 of the high-pressure fuel pump. The suction joint 51 is connected to a low-pressure pipe that supplies fuel from the fuel tank 20 of the vehicle, from which fuel is supplied to the inside of the high-pressure fuel pump. The suction filter 52 (see FIG. 3) in the suction joint 51 has a role of preventing foreign matter existing between the fuel tank 20 and the low-pressure fuel suction port 10a from being absorbed into the high-pressure fuel pump by the flow of fuel.

As shown in FIG. 1, the fuel that has passed through the low-pressure fuel suction port 10a reaches the suction port 31b of the electromagnetic suction valve mechanism 300 via the metal damper 9 and the suction passage 10d (low-pressure fuel flow path).

The electromagnetic suction valve mechanism 300 will be described in detail with reference to FIG. The coil portion includes a first yoke 42, a coil 43 (electromagnetic coil), a second yoke 44, a bobbin 45, a terminal 46 (see FIG. 1), and a connector 47 (see FIG. 1). A coil 43 in which a copper wire is wound around the bobbin 45 a plurality of times is arranged so as to be surrounded by a first yoke 42 and a second yoke 44, and is molded and fixed integrally with a connector which is a resin member. Each end of the two terminals 46 is connected to both ends of the copper wire of the coil so as to be energized. The terminal 46 is molded integrally with the connector 47, and the remaining end can be connected to the engine control unit side.

The coil portion is fixed by press-fitting the outer core 38 into the hole portion at the center of the first yoke 42. At that time, the inner diameter side of the second yoke 44 is configured to be in contact with or close to the fixed core 39 (magnetic core) with a slight clearance.

Both the first yoke 42 and the second yoke 44 are made of magnetic stainless steel in order to form a magnetic circuit and in consideration of corrosion resistance, and the bobbin 45 and the connector 47 are made of high-strength heat-resistant resin in consideration of strength characteristics and heat resistance characteristics. .. The coil 43 is made of copper, and the terminal 46 is made of brass plated with metal.

In this way, when a magnetic circuit is formed by the outer core 38, the first yoke 42, the second yoke 44, the fixed core 39, and the anchor 36 and a current is applied to the coil, a magnetic attraction force is generated between the fixed core 39 and the anchor 36. It is generated and a force that attracts each other is generated. In the outer core 38, by making the axial portion where the fixed core 39 and the anchor 36 generate magnetic attraction with each other as thin as possible, almost all of the magnetic flux passes between the fixed core 39 and the anchor 36, which is efficient. A good magnetic attraction can be obtained.

As shown in FIG. 4, the fixed core 39 has a magnetic attraction surface 39S0 (first surface) that magnetically attracts the anchor 36 and a flat surface portion 39S2 (second surface) opposite to the magnetic attraction surface 39S0. It has a convex portion 39p on the flat surface portion 39S2. Details of the shape of the convex portion 39p will be described later with reference to FIG. 6 and the like.

The solenoid mechanism portion includes a rod 35 which is a movable portion, an anchor 36, a rod guide 37 which is a fixed portion, an outer core 38, a fixed core 39, a rod urging spring 40, and an anchor urging spring 41.

The rod 35 and the anchor 36, which are movable parts, are formed as separate members. The rod 35 is slidably held on the inner peripheral side of the rod guide 37 in the axial direction, and the inner peripheral side of the anchor 36 is slidably held on the outer peripheral side of the rod 35. That is, both the rod 35 and the anchor 36 are configured to be slidable in the axial direction within a range geometrically regulated.

Since the anchor 36 moves freely and smoothly in the axial direction in the fuel, the anchor 36 has one or more through holes 36a penetrating in the axial direction of the component, and the restriction of movement due to the pressure difference between the front and rear of the anchor is eliminated as much as possible.

The rod guide 37 is inserted in the radial direction on the inner peripheral side of the hole into which the suction valve of the pump body 1 (high pressure fuel pump body) is inserted, and is abutted against one end of the suction valve seat in the axial direction. The outer core 38, which is welded and fixed to the pump body 1, and the pump body 1 are sandwiched between the outer core 38 and the pump body 1. Like the anchor 36, the rod guide 37 is also provided with a through hole 37a that penetrates in the axial direction so that the pressure in the fuel chamber on the anchor side does not hinder the movement of the anchor so that the anchor can move freely and smoothly. It is configured.

The outer core 38 has a thin-walled cylindrical shape on the side opposite to the portion to be welded to the pump body 1, and is welded and fixed by inserting the fixing core 39 on the inner peripheral side thereof. A rod urging spring 40 is arranged on the inner peripheral side of the fixed core 39 with a small diameter portion of the rod 35 as a guide, and the rod 35 comes into contact with the suction valve 30 and pulls the suction valve away from the suction valve seat 31a. That is, an urging force is applied in the valve opening direction of the suction valve.

The anchor urging spring 41 is arranged to give urging force to the anchor 36 in the direction of the brim portion 35a of the rod 35 while maintaining the coaxiality by inserting the direction end into the cylindrical central bearing portion 37b provided on the center side of the rod guide 37. It is supposed to be. The movement amount 36e of the anchor 36 is set to be larger than the movement amount 30e of the suction valve 30. This is because the suction valve 30 is surely closed.

Since the rod 35 and the rod guide 37 slide on each other and the rod 35 repeatedly collides with the suction valve 30, martensitic stainless steel that has been heat-treated is used in consideration of hardness and corrosion resistance. Magnetic stainless steel is used for the anchor 36 and the fixed core 39 to form a magnetic circuit, and austenitic stainless steel is used for the rod urging spring 40 and the anchor urging spring 41 in consideration of corrosion resistance.

According to the above configuration, three springs are organically arranged in the suction valve portion and the solenoid mechanism portion. The suction valve urging spring 33 formed in the suction valve portion, the rod urging spring 40 formed in the solenoid mechanism portion, and the anchor urging spring 41 correspond to this. In the present embodiment, coil springs are used for all the springs, but any spring can be configured as long as it can obtain an urging force.

As shown in FIG. 2, the discharge valve mechanism 8 provided at the outlet of the pressurizing chamber 11 directs the discharge valve seat 8a, the discharge valve 8b that comes into contact with and separates from the discharge valve seat 8a, and the discharge valve 8b toward the discharge valve seat 8a. It is composed of a discharge valve spring 8c for urging and a discharge valve stopper 8d for determining a stroke (moving distance) of the discharge valve 8b. The discharge valve stopper 8d and the pump body 1 are joined by welding at the contact portion 8e to shield the fuel from the outside.

When there is no fuel differential pressure between the pressurizing chamber 11 and the discharge valve chamber 12a, the discharge valve 8b is crimped to the discharge valve seat 8a by the urging force of the discharge valve spring 8c to be in a closed state. Only when the fuel pressure in the pressurizing chamber 11 becomes higher than the fuel pressure in the discharge valve chamber 12a does the discharge valve 8b open against the discharge valve spring 8c. Then, the high-pressure fuel in the pressurizing chamber 11 is discharged to the common rail 23 through the discharge valve chamber 12a, the fuel discharge passage 12b, and the fuel discharge port 12.

When the discharge valve 8b is opened, it comes into contact with the discharge valve stopper 8d and the stroke is limited. Therefore, the stroke of the discharge valve 8b is appropriately determined by the discharge valve stopper 8d. As a result, it is possible to prevent the fuel discharged at high pressure into the discharge valve chamber 12a from flowing back into the pressurizing chamber 11 due to the delay in closing the discharge valve 8b due to the stroke being too large, and the efficiency of the high pressure fuel pump is reduced. Can be suppressed. Further, when the discharge valve 8b repeats the valve opening and closing movements, the discharge valve 8b is guided by the outer peripheral surface of the discharge valve stopper 8d so that the discharge valve 8b moves only in the stroke direction. By doing so, the discharge valve mechanism 8 becomes a check valve that limits the fuel flow direction.

The pressurizing chamber 11 is composed of a pump body 1 (pump housing), an electromagnetic suction valve mechanism 300, a plunger 2, a cylinder 6, and a discharge valve mechanism 8.

When the plunger 2 moves in the direction of the cam 93 due to the rotation of the cam 93 and is in the suction stroke state, the volume of the pressurizing chamber 11 increases and the fuel pressure in the pressurizing chamber 11 decreases. When the fuel pressure in the pressurizing chamber 11 becomes lower than the pressure in the suction port 31b in this stroke, the suction valve 30 is opened. As shown in FIG. 4, the fuel passes through the opening 31c of the suction valve 30 and flows into the pressurizing chamber 11.

After the plunger 2 finishes the inhalation stroke, the plunger 2 shifts to an ascending motion and shifts to a compression stroke. Here, the coil 43 remains in a non-energized state and no magnetic urging force acts on it. The rod urging spring 40 is set to have a urging force necessary and sufficient to keep the suction valve 30 open in a non-energized state. The volume of the pressurizing chamber 11 decreases with the compression movement of the plunger 2. In this state, the fuel once sucked into the pressurizing chamber 11 is sucked again through the opening 31c of the suction valve 30 in the opened state. Since it is returned to the passage 10d, the pressure in the pressurizing chamber does not rise. This process is called the return process.

In this state, when the control signal from the ECU 27 is applied to the electromagnetic suction valve mechanism 300, a current flows through the coil 43 via the terminal 46. Then, a magnetic attraction force acts between the fixed core 39 and the anchor, whereby the magnetic urging force overcomes the urging force of the rod urging spring 40 and the rod 35 moves in the direction away from the suction valve 30. Therefore, the suction valve 30 is closed by the urging force of the suction valve urging spring 33 and the fluid force caused by the fuel flowing into the suction passage 10d. After the valve is closed, the fuel pressure in the pressurizing chamber 11 rises with the ascending motion of the plunger 2, and when the pressure exceeds the pressure of the fuel discharge port 12, high-pressure fuel is discharged through the discharge valve mechanism 8 to the common rail 23. Be supplied. This process is called a discharge process.

That is, the compression stroke of the plunger 2 (the ascending stroke from the lower start point to the upper start point) consists of a return stroke and a discharge stroke. Then, by controlling the energization timing of the electromagnetic suction valve mechanism 300 to the coil 43, the amount of high-pressure fuel discharged can be controlled. If the timing of energizing the coil 43 is advanced, the ratio of the return stroke in the compression stroke is small and the ratio of the discharge stroke is large. That is, less fuel is returned to the suction passage 10d, and more fuel is discharged at high pressure. On the other hand, if the energization timing is delayed, the ratio of the return stroke is large and the ratio of the discharge stroke is small during the compression stroke. That is, more fuel is returned to the suction passage 10d, and less fuel is discharged at high pressure. The timing of energizing the coil 43 is controlled by a command from the ECU 27. By controlling the energization timing of the coil 43 as described above, the amount of fuel discharged at high pressure can be controlled to the amount required by the internal combustion engine.

As shown in FIG. 1, a metal damper 9 is installed in the low-pressure fuel chamber 10 to reduce the pressure pulsation generated in the high-pressure fuel pump from spreading to the suction pipe 28 (fuel pipe). When the fuel that has once flowed into the pressurizing chamber 11 is returned to the suction passage 10d through the suction valve 30 (suction valve body) in the opened state again for capacity control, the low pressure fuel is produced by the fuel returned to the suction passage 10d. Pressure pulsation occurs in the chamber 10. However, the metal damper 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 bonded together on the outer periphery thereof and an inert gas such as argon is injected therein. 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 sub chamber 7a increases or decreases due to the reciprocating motion of the plunger 2. The sub chamber 7a communicates with the low pressure fuel chamber 10 by a fuel passage 10e (see FIG. 3). When the plunger 2 is lowered, a fuel flow is generated from the sub chamber 7a to the low pressure fuel chamber 10, and when the plunger 2 is raised, a fuel flow is generated from the low pressure fuel chamber 10 to the sub chamber 7a.

As a result, it is possible to reduce the fuel flow rate inside and outside the pump during the suction stroke or the return stroke of the pump, and it has a function of reducing the pressure pulsation generated inside the high-pressure fuel pump.

Next, the relief valve mechanism 200 shown in FIGS. 1 and 2 will be described.

The relief valve mechanism 200 includes a relief body 201, a relief valve 202, a relief valve holder 203, a relief spring 204, and a spring stopper 205. The relief body 201 is provided with a seat portion. In the relief valve 202, the load of the relief spring 204 is applied via the relief valve holder 203, is pressed against the seat portion of the relief body 201, and shuts off the fuel in cooperation with the seat portion. The valve opening pressure of the relief valve 202 is determined by the load of the relief spring 204. The spring stopper 205 is press-fitted and fixed to the relief body 201, and the load of the relief spring 204 is adjusted according to the press-fitting and fixing position.

Here, when the fuel in the pressurizing chamber 11 is pressurized and the discharge valve 8b is opened, the high-pressure fuel in the pressurizing chamber 11 passes through the discharge valve chamber 12a and the fuel discharge passage 12b and is transmitted from the fuel discharge port 12. It is discharged. The fuel discharge port 12 is formed in a discharge joint, and the discharge joint is welded and fixed to the pump body 1 to secure a fuel passage.

When the pressure of the fuel discharge port 12 becomes abnormally high due to a failure of the electromagnetic suction valve mechanism 300 of the high-pressure fuel pump and becomes larger than the set pressure of the relief valve mechanism 200, the abnormally high-pressure fuel enters the pressurizing chamber via the relief passage 210. Relieved to 11.

Hereinafter, the structure of the electromagnetic suction valve mechanism of the present embodiment will be described in detail with reference to FIGS. 6 to 8.

Two parts, a leaf spring 80 inserted into the fixed core 39 and a retaining ring 70 for fixing the leaf spring 80, are arranged on the opposite side of the end surface 44S that comes into contact with the fixed core 39 of the second yoke 44. Specifically, the retaining ring 70, the leaf spring 80, and the second yoke 44 are arranged in this order from the side closer to the end surface 39S1 of the fixed core 39. That is, the retaining ring 70, the leaf spring 80 (elastic body), and the second yoke 44 (yoke) are arranged in order from the tip of the convex portion 39p toward the root.

The retaining ring 70 makes it possible to compress and fix the leaf spring 80. The leaf spring 80 is compressed to generate a desired urging force, and the second yoke 44 can be urged to the fixed core 39. Further, the inner diameter side of the second yoke 44 is configured to be in contact with or close to the fixed core 39 with a slight clearance.

Here, the fixed core 39 has a convex shape on the side opposite to the end face facing the anchor 36. That is, the fixed core 39 includes a convex portion 39p protruding to the left side of FIG. Further, the fixed core 39 includes a flat surface portion 39S2 in which a convex portion 39p is arranged and is formed from the outermost diameter, so that the end surface 44S (lower end surface) of the second yoke 44 comes into contact with the flat surface portion 39S2 of the fixed core 39. It is configured.

Further, the fixed core 39 has a columnar portion 39a formed by expanding the outer diameter portion, and as shown in FIG. 8A, the flat surface portion 39a-1 of the columnar portion 39a and the end surface 70-1 of the retaining ring 70 ( The upper end surface) is configured to abut.

In other words, as shown in FIG. 6, the second yoke 44 (yoke) is inserted through the convex portion 39p and is in contact with the flat surface portion 39S2 (second surface) of the fixed core 39. The leaf spring 80 (elastic body) is inserted through the convex portion 39p and urges the second yoke 44 (yoke). The retaining ring 70 is inserted through the convex portion 39p to fix one end of the leaf spring 80 (elastic body).

As a result, the retaining ring 70 is held by the fixed core 39 in the axial direction, so that the retaining ring 70 can be made difficult to separate in the axial direction opposite to the leaf spring 80, and the axial direction of the leaf spring 80 can be prevented. It becomes possible to fix the second yoke 44 by receiving the urging force of.

Further, as shown in FIG. 8A, the fixed core 39 has a groove portion 39d into which the leaf spring 80 or the retaining ring 70 is inserted, and has an end surface (a surface facing the anchor 36) constituting the magnetic pole of the fixed core 39. A cylindrical portion 39c, a tapered portion 39b (conical portion), and a cylindrical portion 39a are formed between the end surface 39S1 on the opposite side and the groove portion 39d. As shown in FIG. 8B, only the tapered portion 39b and the cylindrical portion 39a are formed between the end surface 39S1 and the groove portion 39d, and the cylindrical portion 39c may not be formed.

In other words, the convex portion 39p of the fixed core 39 has a tapered portion 39b (conical portion) as shown in FIG. 8A or FIG. 8B. Further, as shown in FIG. 8A, the convex portion 39p of the fixed core 39 has a cylindrical portion 39c (cylindrical portion). The cylindrical portion 39c and the tapered portion 39b (conical portion) are arranged in order from the tip of the convex portion 39p toward the root.

As a result, the cylindrical portion 39c can function as a guide portion for the leaf spring 80 or the retaining ring 70. Further, the tapered portion 39b can prevent the insertion load from becoming excessive and improve the assembling property. Further, it becomes possible to fix the assembly assisting jig of the part to be inserted into the fixing core 39.

As shown in FIG. 8A, the convex portion 39p of the fixed core 39 has a groove portion 39d (first groove portion), and the groove portion 39d2 (second groove portion) is located at the bottom of the groove portion 39d on the tip side of the convex portion 39p. ). As a result, for example, the degree of freedom of R (fillet radius) of the retaining ring 70 is improved.

As shown in FIGS. 9 and 10, the retaining ring 70 provided in the fixed core 39 includes a slit portion 70a (notch portion) in a part thereof, and the slit portion 70a has a maximum width Wmax of the retaining ring 70. It is composed of the above. That is, the retaining ring 70 has a slit portion 70a (slit) having a width larger than the maximum width Wmax in the radial direction of the retaining ring 70. As a result, even if the retaining rings 70 are entangled with each other, the entanglement can be easily released.

Further, as shown in FIGS. 11 and 12, the slit portion 70a of the retaining ring 70 may be formed with a plate thickness t or less. That is, the retaining ring 70 has a slit portion 70a (slit) having a width smaller than the plate thickness of the retaining ring 70. This makes it possible to suppress the entanglement of the retaining rings 70.

As described above, according to the present embodiment, the yoke can be easily fixed by a retaining ring that does not get entangled or can be easily released from the entanglement.

The present invention is not limited to the above-described embodiment, and includes various modifications. For example, the above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to the one including all the configurations. Further, it is possible to add / delete / replace a part of the configuration of the embodiment with another configuration.

In the above embodiment, the leaf spring 80 is used to urge the second yoke 44, but an elastic body such as a disc spring may be used.

The embodiment of the present invention may have the following aspects.

(1). A first yoke including an electromagnetic drive unit having a coil, a fixed core, and an anchor portion, and a rod driven by the electromagnetic drive unit to operate an on-off valve, and forming a magnetic path so as to surround the lower end surface and the outer peripheral side of the coil. A second yoke forming a magnetic path is provided on the upper end surface side of the coil, and the coil and the first yoke are fixed by a connector formed of resin, and the coil and the first yoke are attached to the first yoke. The provided central hole is press-fitted and fixed at a position facing the end face forming the magnetic pole of the fixed core with the outer peripheral portion of the outer core coupled to the fixed core by a ring member to form the magnetic pole of the fixed core. In the electromagnetic suction valve mechanism in which the end face of the rod faces the rod with a gap formed in the operation direction of the on-off valve of the rod and the rod moves between the gaps by energizing the coil, the second yoke is used. On the opposite side of the end face that comes into contact with the fixed core, two parts, a leaf spring inserted into the fixed core and a retaining ring for fixing the leaf spring, are inserted into the fixed core from the end face direction. An electromagnetic suction valve mechanism characterized in that a leaf spring and the second yoke are configured in this order.

(2). The retaining ring provided in the electromagnetic suction valve mechanism according to (1) is characterized in that the retaining ring is partially provided with a notch, and the width of the notch is equal to or larger than the maximum width of the retaining ring.

(3). The retaining ring provided in the electromagnetic suction valve mechanism according to (1) is characterized in that the retaining ring is partially provided with a notch, and the notch is formed so as to be smaller than the plate thickness of the retaining ring.

(4). In the electromagnetic suction valve mechanism according to (1), the fixed core has a cylindrical portion formed by expanding the outer diameter portion of the fixed core, and is above the end surface of the cylindrical portion and the retaining ring. An electromagnetic suction valve mechanism characterized in that the end faces are in contact with each other.

(5). In the electromagnetic suction valve mechanism according to (1), the fixed core has a groove into which the second yoke, the leaf spring, and the retaining ring are inserted, and is opposite to the end face forming the magnetic pole of the fixed core. An electromagnetic suction valve mechanism characterized by having a cylindrical portion and a conical portion between the groove and the other end / surface of the above.

(6). In the electromagnetic suction valve mechanism according to (5), the fixed core has a conical portion between the groove on the opposite side of the end surface forming the magnetic pole of the fixed core and the other end surface. Valve mechanism.

According to (1) to (6), the assemblability of the high-pressure fuel pump is dramatically improved.

1 ... Pump body 1e ... Flange 1p ... Damper accommodating part 2 ... Plunger 2a ... Large diameter part 2b ... Small diameter part 4 ... Spring 6 ... Cylinder 6a ... Fixed part 7 ... Seal holder 7a ... Sub chamber 8 ... Discharge valve mechanism 8a ... Discharge Valve seat 8b ... Discharge valve 8c ... Discharge valve spring 8d ... Discharge valve stopper 8e ... Contact portion 9 ... Metal damper 9a ... Holding member 10 ... Low pressure fuel chamber 10a ... Low pressure fuel suction port 10d ... Suction passage 10e ... Fuel passage 11 ... Pressurizing chamber 12 ... Fuel discharge port 12a ... Discharge valve chamber 12b ... Fuel discharge passage 13 ... Plunger seal 14 ... Damper cover 15 ... Retainer 20 ... Fuel tank 21 ... Feed pump 23 ... Common rail 24 ... Injector 26 ... Pressure sensor 27 ... Engine Control unit 28 ... Suction pipe 30 ... Suction valve 30e ... Movement amount 31a ... Suction valve seat 31b ... Suction port 31c ... Opening 33 ... Suction valve urging spring 35 ... Rod 35a ... Brim 36 ... Anchor 36a ... Through hole 36e ... Amount of movement 37 ... Rod guide 37a ... Through hole 37b ... Central bearing portion 38 ... Outer core 39 ... Fixed core 39a ... Column portion 39a-1 ... Flat portion 39b ... Tapered portion 39c ... Column portion 39d ... Groove portion 39p ... Convex portion 39S1 ... End face 39S2 ... Flat surface 40 ... Rod urging spring 41 ... Anchor urging spring 42 ... First yoke 43 ... Coil 44 ... Second yoke 44S ... End face 45 ... Bobbin 46 ... Terminal 47 ... Connector 51 ... Suction joint 52 ... Suction filter 61 ... O-ring 70 ... Stop ring 70-1 ... End face 70a ... Slit portion 80 ... Leaf spring 90 ... High-pressure fuel pump mounting portion 92 ... Tappet 93 ... Cam 200 ... Relief valve mechanism 201 ... Relief body 202 ... Relief valve 203 ... Relief Valve holder 204 ... Relief spring 205 ... Spring stopper 210 ... Relief passage 300 ... Electromagnetic suction valve mechanism

Claims (5)

Anchor and
A fixed core having a first surface that magnetically attracts the anchor, a second surface opposite to the first surface, and a protrusion on the second surface.
A yoke that is inserted through the convex portion and is in contact with the second surface,
An elastic body that is inserted through the convex portion and urges the yoke,
A retaining ring that is inserted through the convex portion and fixes one end of the elastic body is provided.
The retaining ring
A high-pressure fuel pump having a slit having a width larger than the maximum radial width of the retaining ring or smaller than the plate thickness of the retaining ring.
The convex portion has a conical portion and a first groove portion in which the retaining ring and the elastic body are arranged in the order from the tip of the convex portion to the root.
A high-pressure fuel pump characterized in that the diameter of the first groove portion is larger than the minimum diameter of the conical portion and smaller than the maximum diameter of the conical portion. The high-pressure fuel pump according to claim 1.
The retaining ring, the elastic body, and the yoke are
A high-pressure fuel pump characterized in that it is arranged in order from the tip of the convex portion toward the root. The high-pressure fuel pump according to claim 1.
The high-pressure fuel pump is characterized in that the convex portion has a first columnar portion between the conical portion and the first groove portion. The high-pressure fuel pump according to claim 3.
The convex part is
It also has a second columnar part,
The second columnar portion , the conical portion, and the first columnar portion are
A high-pressure fuel pump characterized in that it is arranged in order from the tip of the convex portion toward the root. The high-pressure fuel pump according to claim 1 .
At the bottom of the first groove on the tip side of the convex portion,
A high-pressure fuel pump characterized by having a second groove.

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