JP2021059991A - High pressure fuel supply pump - Google Patents

Abstract

To provide a high pressure fuel supply pump that downsizes a solenoid valve mechanism and improves a layout property.SOLUTION: A high pressure fuel supply pump 1 has a solenoid valve mechanism 300. The solenoid valve mechanism 300 is equipped with a fixed core 44, a moving core 45 disposed at a position opposite to the fixed core 44, a guide member 46 fixed so as to fix the moving core 45 to the fixed core 44 in a separating/contacting direction, and a housing 42 that stores the fixed core 44, the moving core 45, and the guide member 46. The guide member 46 has a collar portion 46c bulging outward in a diametrical direction, and the collar portion 46c is fixed by being held between the housing 42 and the fixed core 44.SELECTED DRAWING: Figure 3

Description

The present invention relates to a high pressure fuel supply pump for an internal combustion engine of an automobile.

Some high-pressure fuel supply pumps for internal combustion engines of automobiles use a solenoid valve mechanism (solenoid intake valve unit) for adjusting the fuel flow rate. The solenoid valve mechanism controls the opening / closing motion of the valve by energizing the coil.

In the solenoid valve mechanism, when energization of the coil is started, a magnetic attraction force is generated between the movable core (movable core) and the fixed core (fixed core), and the movement of the movable core to the fixed core side is started. ..

As a prior art of a high-pressure fuel supply pump, a high-pressure fuel supply pump described in Japanese Patent Application Laid-Open No. 2015-108409 (Patent Document 1) is known. Conventionally, when the movable iron core moves the distance of the gap formed between the fixed core and the movable core, it generally collides with the fixed core and stops. However, the high-pressure fuel supply pump of Patent Document 1 has a structure that avoids a collision between the movable core and the fixed core by providing a collision portion as a means for defining the amount of movement of the moving parts in addition to the movable core and the fixed core. It is equipped with a solenoid valve (solenoid valve mechanism) (see summary).

Specifically, the solenoid valve mechanism is provided with a ring-shaped component that is press-fitted and fixed on the inner diameter side of the fixed core, and the ring-shaped component collides with a rod provided on the inner diameter side of the movable core to cause the movable core and the fixed core. Avoid collisions with (see paragraphs 0028 and Figures 3 and 4).

Japanese Unexamined Patent Publication No. 2015-108409

The solenoid valve mechanism of Patent Document 1 has a structure in which a ring-shaped component is press-fitted and fixed inward in the radial direction of a fixed iron core. In this way, in the structure in which the part (press-fitted part) is press-fitted and fixed inside the fixed iron core in the radial direction, the press-fitted part (ring-shaped part of Patent Document 1) and the member length of the fixed iron core are set in order to secure the press-fitting length. It is necessary to secure it, and the solenoid valve mechanism may become large and the layout of the high-pressure fuel supply pump may be deteriorated.

An object of the present invention is to provide a high-pressure fuel supply pump having an improved layout by downsizing the solenoid valve mechanism.

In order to achieve the above object, the high pressure fuel supply pump of the present invention
A high-pressure fuel supply pump with a solenoid valve mechanism
The solenoid valve mechanism is
With a fixed core
A movable core arranged at a position facing the fixed core,
A guide member fixed so as to guide the movable core in a direction in which the movable core is brought into contact with or separated from the fixed core.
A housing that houses the fixed core, the movable core, and the guide member,
With
The guide member has a brim portion that projects outward in the radial direction, and the brim portion is sandwiched and fixed between the housing and the fixing core.

According to the present invention, in a high-pressure fuel supply pump provided with a guide member of a movable core inside the fixed core of the solenoid valve mechanism in the radial direction, the solenoid valve mechanism is provided by providing a fixing portion by a non-press-fit portion as a fixing portion of the guide member. The size can be reduced and the layout of the high-pressure fuel supply pump can be improved.
Issues, configurations and effects other than the above will be clarified by the following description of the embodiments.

It is a block diagram which shows the fuel supply system of the internal combustion engine including the high pressure fuel supply pump provided with the solenoid valve mechanism which concerns on 1st Embodiment of this invention. It is sectional drawing which shows the high pressure fuel supply pump provided with the solenoid valve mechanism which concerns on 1st Embodiment of this invention. It is an enlarged view of the solenoid valve mechanism shown in FIG. It is the schematic which shows the guide structure of the movable core in the solenoid valve mechanism shown in FIG. It is an enlarged view of the solenoid valve mechanism which concerns on 2nd Embodiment of this invention.

Hereinafter, an embodiment of the high-pressure fuel supply pump of the present invention will be described with reference to the drawings. In the following description, the vertical direction may be specified, but this vertical direction is based on the vertical direction of FIGS. 1 and 2, and specifies the vertical direction in the mounted state of the high-pressure fuel supply pump. is not it.

[Example 1]
(Fuel supply system)
First, the configuration of the high-pressure fuel supply pump 1 provided with the solenoid valve mechanism and the configuration of the fuel supply system of the internal combustion engine including the high-pressure fuel supply pump 1 according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 2. To do. FIG. 1 is a configuration diagram showing a fuel supply system of an internal combustion engine including a high-pressure fuel supply pump provided with a solenoid valve mechanism according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view showing a high-pressure fuel supply pump provided with a solenoid valve mechanism according to the first embodiment of the present invention.

In FIG. 1, the fuel supply system of the internal combustion engine pressurizes, for example, a fuel tank 101 for storing fuel, a feed pump 102 for pumping and delivering fuel in the fuel tank 101, and fuel sent from the feed pump 102. It includes a high-pressure fuel supply pump 1 for discharging the fuel, and a plurality of injectors 103 for injecting the high-pressure fuel pumped from the high-pressure fuel supply pump 1. This system is a so-called direct injection engine system that injects fuel directly into the cylinder cylinder of an engine as an internal combustion engine.

The high-pressure fuel supply pump 1 is connected to the feed pump 102 via the suction pipe 104 and is connected to the injector 103 via the common rail 105. The injectors 103 are mounted on the common rail 105 in an number corresponding to the number of cylinders of the engine, and are controlled to open or close in response to a control signal from the engine control unit (hereinafter, referred to as an ECU) 107. The common rail 105 is equipped with a pressure sensor 106 that detects the pressure of the fuel discharged from the high-pressure fuel supply pump 1. The pressure sensor 106 outputs a pressure detection signal to the ECU 107.

The high-pressure fuel supply pump 1 includes a pump housing 1a having a pressurizing chamber 4 for pressurizing fuel inside, a plunger 5 assembled to the pump housing 1a, an electromagnetic valve mechanism (electromagnetic suction valve unit) 300, and discharge. It includes a valve unit 500 and. The plunger 5 pressurizes the fuel in the pressurizing chamber 4 by reciprocating motion. The solenoid valve mechanism 300 functions as a capacity variable mechanism for adjusting the flow rate of fuel sucked into the pressurizing chamber 4, and is controlled by a control signal from the ECU 107. The discharge valve unit 500 discharges the fuel pressurized by the plunger 5 to the common rail 105 side. Although not shown, the high-pressure fuel supply pump 1 includes a relief valve that relieves the fuel on the common rail 105 side that has become abnormally high pressure into the pressurizing chamber 4 or the fuel passage on the low-pressure side.

As shown in FIGS. 1 and 2, a bottomed tubular (cup-shaped) damper cover 10 is fixed to the tip end side (upper end portion side in FIGS. 1 and 2) of the pump housing 1a. A suction joint 11 is attached to the damper cover 10, and the suction joint 11 forms a low-pressure fuel suction port 2a of the high-pressure fuel supply pump 1. A suction filter 12 is installed in the suction joint 11. The suction filter 12 has a role of preventing foreign matter existing between the fuel tank 101 and the low-pressure fuel suction port 2a from being absorbed into the high-pressure fuel supply pump 1 by the flow of fuel.

A low-pressure fuel chamber 2b as a part of the fuel flow path is formed on the upstream side of the pressurizing chamber 4 by the tip end portion of the pump housing 1a and the damper cover 10. A pressure pulsation reducing mechanism 14 is arranged in the low pressure fuel chamber 2b. The pressure pulsation reducing mechanism 14 reduces the spread of the pressure pulsation generated in the high-pressure fuel supply pump 1 to the suction pipe 104, and is formed on the upstream side of the solenoid valve mechanism 300.

A tappet 6 is provided on the tip end side (lower end side in FIG. 1) of the plunger 5 to convert the rotational motion of the cam 108 of the engine into a linear reciprocating motion. The plunger 5 is crimped to the tappet 6 by the urging force of the spring 8 via the retainer 7 fixed to the tip of the plunger 5. As a result, the plunger 5 can be reciprocated with the rotational movement of the cam 108.

A solenoid valve mechanism 300 is provided on the inlet side of the pressurizing chamber 4 of the pump housing 1a. The details of the configuration of the solenoid valve mechanism 300 will be described later, but the suction valve 31 is configured to open and close based on the control signal of the ECU 107.

As shown in FIG. 2, a discharge passage 2c is formed on the outlet side of the pressurizing chamber 4 of the pump housing 1a, and a discharge valve unit 500 is provided in the discharge passage 2c. A discharge joint 16 is provided on the downstream side of the discharge valve unit 500 in the discharge passage 2c, and the discharge joint 16 forms the fuel discharge port 2e of the high-pressure fuel supply pump 1.

The discharge valve unit 500 includes a discharge valve seat 51, a discharge valve 52 that comes into contact with and separates from the discharge valve seat 51, a discharge valve spring 53 that urges the discharge valve 52 toward the discharge valve seat 51, and a discharge valve seat 51. It is partially composed of a discharge valve holder 54 for accommodating a discharge valve 52 and a discharge valve spring 53. The discharge valve seat 51 is press-fitted and held in the discharge passage 2c of the pump housing 1a, for example. In the discharge valve unit 500, the discharge valve seat 51 and the discharge valve holder 54 are joined by welding to form a unit in which the discharge valve seat 51, the discharge valve 52, the discharge valve spring 53, and the discharge valve holder 54 are integrated. There is.

In the discharge valve unit 500, the discharge valve 52 is pressed against the discharge valve seat 51 by the urging force of the discharge valve spring 53 in a state where there is no fuel differential pressure between the pressurizing chamber 4 and the inside of the discharge joint 16, and the valve is closed. It is configured to be. On the other hand, when the fuel pressure in the pressurizing chamber 4 becomes higher than the fuel pressure inside the discharge joint 16, the discharge valve 52 is configured to open against the urging force of the discharge valve spring 53. Further, the inner peripheral surface of the discharge valve holder 54 guides the discharge valve 52, and the discharge valve 52 is configured to move only in the lift direction during the valve opening and closing movements. With the above configuration, the discharge valve unit 500 functions as a check valve that limits the fuel flow direction in one direction to prevent backflow.

In this fuel supply system, as shown in FIGS. 1 and 2, the fuel in the fuel tank 101 is pumped by the feed pump 102 and pressurized to an appropriate feed pressure, and the high pressure fuel supply pump 1 passes through the suction pipe 104. It is sent to the low pressure fuel suction port 2a. The fuel that has passed through the low-pressure fuel suction port 2a passes through the suction filter 12 and reaches the solenoid valve mechanism 300 via the pressure pulsation reduction mechanism 14 in the low-pressure fuel chamber 2b. The fuel that has flowed into the solenoid valve mechanism 300 passes through the suction valve 31 that opens and closes based on the control signal of the ECU 107. The fuel that has passed through the suction valve 31 is sucked into the pressurizing chamber 4 in the descending stroke of the reciprocating plunger 5, and is pressurized in the pressurizing chamber 4 in the ascending stroke of the plunger 5. The fuel pressurized in the pressurizing chamber 4 passes through the discharge valve unit 500, is pumped to the common rail 105 through the fuel discharge port 2d. The high-pressure fuel in the common rail 105 is injected into the cylinder cylinder of the engine by the injector 103. The high-pressure fuel supply pump 1 discharges a desired flow rate fuel in response to a control signal from the ECU 107 to the solenoid valve mechanism 300.

Next, the configuration and details of the structure of the solenoid valve mechanism 300 according to the first embodiment of the present invention will be described with reference to FIGS. 3 and 4. FIG. 3 is an enlarged view of the solenoid valve mechanism shown in FIG. FIG. 4 is a schematic view showing a guide structure of a movable core in the solenoid valve mechanism shown in FIG. Note that FIG. 3 shows a state in which the solenoid valve mechanism 300 is not energized.

In FIG. 3, the solenoid valve mechanism 300 is roughly classified into a valve mechanism portion including a suction valve 31 and a solenoid mechanism portion including a coil 41 and a movable core 45. The valve mechanism portion includes a suction valve 31, a suction valve seat member 32, a suction valve stopper 33, and a first urging spring 34.

The suction valve seat member 32 is, for example, a bottomed tubular member that opens on one side (right side in FIG. 3) and has a central axis A1. That is, the suction valve seat member 32 has a tubular portion (cylindrical portion) 32A centered on the central axis A1 and a bottom portion 32B that closes the end portion of the tubular portion 32A on the fixed core 44 side.

The suction valve seat member 32 has an annular valve seat portion 32a on which the suction valve 31 can be seated at an intermediate position in the axial direction (direction along the central axis A1) of the tubular portion 32A. That is, inside the tubular portion 32A of the suction valve seat member 32, the suction valve 31 is movably arranged so as to be seated or separated from the valve seat portion 32a. The tubular portion 32A of the suction valve seat member 32 is provided with a plurality of suction ports 32b communicating with the low pressure fuel chamber 2b (see FIG. 2) at intervals in the circumferential direction.

The bottom portion 32B of the suction valve seat member 32 is provided with a guide hole 32c that penetrates along the central axis A1 of the suction valve seat 32. The bottom portion 32B of the suction valve seat member 32 having the guide hole 32c functions as a rod guide portion that slidably supports (guides) the rod 48 described later along the central axis A1 of the suction valve seat member 32. On the outer peripheral side of the guide hole 32c in the bottom portion 32B of the suction valve seat member 32, a through hole 32d penetrating the inside of the tubular portion is provided. The through hole 32d constitutes a flow path for enabling the movement of fuel in the solenoid valve mechanism 300 with the movement (displacement) of the movable core 45 described later.

A suction valve stopper 33 is press-fitted and fixed to the opening (the end opposite to the bottom portion 32B) of the suction valve seat member 32. The suction valve stopper 33 has a function of regulating the displacement of the suction valve 31 away from the valve seat portion 32a. A first urging spring 34 is arranged between the suction valve 31 and the suction valve stopper 33. That is, the first urging spring 34 has one end in contact with the suction valve 31 and the other end in contact with the suction valve stopper 33, and urges the suction valve 31 toward the valve seat portion 32a (in the direction of closing the valve). ing.

The solenoid mechanism includes, for example, a coil 41 provided in an annular shape, a housing 42 arranged radially inside the coil 41, an annular yoke 43 surrounding the coil 41 and fixed to the outer peripheral portion of the housing 42, and a housing. It is composed of a fixed core 44 housed in the 42, a movable core 45, a guide member 46, a guided member 47, a rod 48, and a second urging spring 49. A control signal from the ECU 107 (see FIG. 1) is input to the coil 41 via a terminal (not shown). In the solenoid mechanism, the yoke 43, the housing 42, the fixed core 44, and the movable core 45 form a magnetic circuit, and the movable core 45, the guided member 47, and the rod 48 form a movable part that drives the suction valve 31. In the movable portion, the movable core 45 and the guided member 47 are integrally provided, but the rod 48 has a separate structure that can be brought into contact with and separated from the movable core 45 and the guided member 47. The present embodiment is characterized by a guide structure that guides the movement of the movable core 45.

The housing 42 is, for example, a bottomed tubular member that opens to one side (the right side in FIG. 3, that is, the suction valve 31 side), and has a central axis A2. That is, the housing 42 has a bottomed tubular shape having a tubular portion 42b into which the fixed core 44 is press-fitted and a bottom portion 42a that closes the end portion of the tubular portion 42b opposite to the movable core 45. The housing 42 and the suction valve seat member 32 are fixed so as to be coaxial with each other. That is, the housing 42 is arranged so that its central axis A2 coincides with the central axis A1 of the suction valve seat member 32. The inner surface of the bottom portion 42a of the housing 42 is formed in a plane orthogonal to the second central axis A2. Here, the coincidence between the central axis A1 and the central axis A2, and the orthogonality between the inner surface of the bottom portion 42a and the second central axis A2 include a deviation based on a tolerance.

A fixed core 44 is arranged on the bottom portion 42a side in the housing 42. The fixed core 44 is formed so as to extend in the axial direction of the housing 42 (direction along the central axis A2), and is fixed by press-fitting the outer peripheral surface thereof into the housing 42, for example. That is, the fixed core 44 is a member having a cylindrical shape centered on the central axis A2, and is press-fitted and fixed in the housing 42.

An accommodating portion 44a capable of accommodating most of the guide member 46 is provided at a position (diametrically central portion) inside the fixed core 44 in the radial direction. The accommodating portion 44a is formed as, for example, a hole portion penetrating in the axial direction. The fixed core 44 forms a part of a magnetic circuit and is made of a magnetic material. As the magnetic material, for example, a material having a Vickers hardness of 200 HV or less is used. The end surface of the fixed core 44 on the housing opening side (movable core 45 side) constitutes a magnetic attraction surface on which a magnetic attraction force acts.

On the opening side in the housing 42, the movable core 45 is arranged so as to face the fixed core 44. The movable core 45 is formed so as to form a gap between the movable core 45 and the inner peripheral surface of the housing 42, and is movable within the housing 42. The movable core 45 forms a part of a magnetic circuit together with the fixed core 44, and is made of a magnetic material. As the magnetic material, for example, a material having a Vickers hardness of 200 HV or less is used as in the case of the fixed core 44.

The housing 42 and the yoke 43 constituting the magnetic circuit are also made of a magnetic material like the fixed core 44 and the movable core 45.

The surface of the movable core 45 facing the fixed core 44 constitutes a magnetic attraction surface on which a magnetic attraction force acts. A fitting portion 45a into which the guided member 47 is fitted is formed at a position inside the movable core 45 in the radial direction (center portion in the radial direction). The fitting portion 45a is formed as, for example, a hole portion penetrating in the axial direction of the housing 42.

A guide member 46 having a central axis A3 is arranged in the accommodating portion 44a of the fixed core 44. The guide member 46 supports the movable core 45 via the guided member 47 at a position inside the movable core 45 in the radial direction (inside the fitting portion 45a), and supports the movable core 45 along the central axis A3 of the guide member 46. It guides the fixed core 44 in the direction of contact and separation.

The guide member 46 has a base portion 46a inserted into the accommodating portion 44a inside the fixed core 44 in the radial direction and an outer diameter larger than that of the base portion 46a, and the bottom portion 42a of the housing 42 and the end of the fixed core 44 on the anti-movable core 45 side. A guide body that has a smaller outer diameter than the base 46a and has a smaller outer diameter than the base 46a and extends from the base 46a to guide the movable core 45 via the guided member 47. It is configured to include 46b and. That is, the guide member 46 has a large-diameter portion formed of the base portion 46a, a small-diameter portion formed of the guide main body 46b, and a brim portion 46c protruding outward in the radial direction from the outer peripheral surface of the large-diameter portion. In other words, the guide member 46 includes a base portion 46a provided with a brim portion 46c at one end, and a guide body 46b provided on the side of the movable core 45 from the other end of the base portion 46a and having a diameter smaller than that of the base portion 46a. Then, the movable core 45 is guided on the end side of the guide body 46c opposite to the base portion 46a.

The cross section perpendicular to the axial direction (direction along the central axis A3) of the base portion 46a, the guide main body 46b, and the brim portion 46c forms a circular shape, and the outer peripheral surfaces of the base portion 46a, the guide main body 46b, and the brim portion 46c form a cylindrical surface. ing.

When the base portion 46a of the guide member 46 is press-fitted into the accommodating portion 44a of the fixed core 44 and fixed to the fixed core 44 only by the base portion 46a, it is necessary to secure (lengthen) the press-fitting length in order to secure the fixing force. However, the brim portion 46c of the guide member 46 is sandwiched between the bottom portion 42a of the housing 42 and the end portion 44b of the fixed core 44 and is abutted and fixed, so that the axial length of the guide member 46 can be reduced. It will be possible. That is, the brim portion 46c is sandwiched between the end portion of the fixed core 44 opposite to the movable core 45 and the bottom portion 42a of the housing 42.

Further, a gap S1 is formed between the accommodating portion (inner circumference) 44a inside the fixed core 44 in the radial direction and the outer diameter (outer peripheral surface) 46d of the base portion 46a of the guide member 46, and the inner peripheral portion (inner circumference) of the housing 42 is formed. The fixed core 44, the guide member 46, and the housing 42 are arranged so that a gap S2 is formed between the peripheral surface) 42b1 and the outer diameter (outer circumference) 46e of the brim portion 46c of the guide member 46.

By adopting the gap structure as described above, the press-fitting process can be eliminated for the structure in which the guide member 46 is press-fitted into the housing 42, so that the assembling property is improved.

Further, in the press-fitting structure, a closed space S2 is formed between the housing 42 and the guide member 46, and the guide member 46 may be lifted by the compressed air. However, as described above, the gap S1 is formed and the gap S1 is formed. By making the guide member 46 non-fixed to the fixed core 44, the gap S2 can secure an air passage communicating with the opening side of the housing 42 through the gap S1. As a result, a closed space is not created between the housing 42 and the guide member 46, that is, the gap S2 does not become a closed space, and the guide member 46 can be prevented from rising.

In order to make this more reliable, the groove portion 46f extending in the radial direction as described in the second embodiment on the surface of the brim portion 46c of the guide member 46 facing the end portion 44b of the fixed core 44. May be provided.

The tip end portion (right end portion in FIG. 3) of the guide main body 46b is formed in a tapered shape. The end surface 46a1 of the base portion 46a on one side in the axial direction of the guide member 46 is formed in a plane orthogonal to the central axis A3. The guide member 46 is arranged so that the end surface 46a1 of the base portion 46a is in contact with the inner surface of the bottom portion 42a of the housing 42, and the central axis A3 thereof is fixed so as to coincide with the central axis A2 of the housing 42. Here, the coincidence between the central axis A2 and the central axis A3 and the orthogonality between the end surface 46a1 of the base portion 46a and the second central axis A3 include a deviation based on a tolerance.

Since the guide member 46 is a portion that comes into contact with the guided member 47 as a movable portion, a material having higher hardness and excellent wear resistance than the fixed core 44 or the movable core 45, for example, austenitic stainless steel or martensitic. It is made of austenitic stainless steel. When austenitic stainless steel is used, the strength can be increased by performing a treatment such as carburizing. When martensitic stainless steel is used, the strength can be increased by heat treatment such as quenching. As a material having excellent wear resistance, for example, a material having a Vickers hardness of about 500 to 800 HV is used.

A guided member 47 is press-fitted into the fitting portion 45a of the movable core 45 to be integrally formed with the movable core 45. The guided member 47 is a bottomed tubular member that opens on one side (the left side in FIG. 3, that is, the fixed core 44 side), and the guide member 46 is arranged inside and is slidable with respect to the guide member 46. It is composed of a tubular portion 47a and a closing portion (bottom portion) 47b that closes an opening on the opposite side (anti-fixing core side) of the tubular portion 47a from the fixed core 44. That is, the guided member 47 has a bottomed tubular shape.

The movable core 45 is supported by the guide member 46 via the guided member 47, and the movable core 45 and the guided member 47 are integrally movable along the central axis A3 of the guide member 46. .. A through hole 47c is provided in the closed portion 47b of the guided member 47. The through hole 47c reduces the fluid resistance when the guided member 47 moves and facilitates the movement of the guided member 47. The guided member 47 is arranged so that the end surface (end portion) of the tubular portion 47a opposite to the closing portion 47b is located inside the fitting portion 45a of the movable core 45.

Since the guided member 47 is a member that slides on the guide member 46, it is preferably formed of a material having substantially the same hardness as the material of the guide member 46. That is, the guided member 47 is formed of a high-strength material having excellent wear resistance, such as austenitic stainless steel and martensitic stainless steel, like the guide member 46. As a material having excellent wear resistance, a material having a Vickers hardness of about 500 to 800 HV is used as in the guide member 46.

The rod 48 has one end in the axial direction (the left end in FIG. 3, that is, the end on the movable core 45 side) that can be brought into contact with and separated from the closed portion 47b of the guided member 47, and the other end in the axial direction. (In FIG. 3, the right end portion, that is, the suction valve 31 side end portion) is configured to be in contact with and detached from the suction valve 31. The rod 48 is inserted into the guide hole 32c of the suction valve seat member 32 and slidably supported by the suction valve seat member 32. That is, the movement of the rod 48 is guided by the inner peripheral wall surface of the guide hole 32c.

The second urging spring 49 is configured to be arranged in the accommodating portion 44a of the fixed core 44, in the fitting portion 45a of the movable core 45, and radially outside the guide main body 46b of the guide member 46. There is. One end of the second urging spring 49 is in contact with the base 46a of the guide member 46, and the other end is in contact with the end surface of the tubular portion 47a of the guided member 47. The second urging spring 49 urges the movable core 45 in a direction away from the fixed core 44 via the guided member 47.

The second urging spring 49 is configured such that the urging force thereof is larger than the urging force of the first urging spring 34. Therefore, when the coil 41 is not energized, the difference between the urging force of the second urging spring 49 and the urging force of the first urging spring 34 causes the integral movable core 45 and the guided member 47 to come into contact with each other. The rod 48 is in contact with the suction valve 31 and urges the suction valve 31 in a direction away from the valve seat portion 32a of the suction valve seat member 32. At this time, the suction valve 31 is opened or closed depending on the pressure in the pressurizing chamber 4 (see FIG. 2).

In the solenoid mechanism portion, the slidable length (guide length) S between the guide member 46 and the guided member 47 is a distance G1 that allows the movable core 45 to move toward the fixed core 44 side by energizing the coil 41. That is, it is configured to be larger than the stroke length of the movable core 45. In this embodiment, the distance G1 is equal to the length of the gap formed between the movable core 45 and the fixed core 44 when the coil 41 is not energized. With this configuration, the movable core 45 and the guided member 47 are reliably and slidably supported by the guide member 46 within the range of the stroke length G1 of the movable core 45.

Further, in the solenoid mechanism portion, as shown in FIG. 4, the difference between the inner diameter D1 of the tubular portion 47a of the guided member 47 and the outer diameter d2 of the guide body 46b of the guide member 46 is movable with the inner diameter D3 of the housing 42. The core 45 is configured to be smaller than the difference from the outer diameter d4. With this configuration, the movable core 45 is reliably supported by the guide member 46 via the guided member 47 without sliding on the inner peripheral portion 42b1 of the housing 42.

(Operation of high-pressure fuel supply pump)
Next, the operation of the high-pressure fuel supply pump 1 will be described with reference to FIGS. 2 and 3. First, the operation of the suction process of the high-pressure fuel supply pump 1 will be described.

In the suction stroke in which the plunger 5 shown in FIG. 2 descends from the top dead center position T indicated by the broken line, the coil 41 of the solenoid valve mechanism 300 is in a non-energized state. When the coil 41 is not energized, in the solenoid valve mechanism 300 shown in FIG. 3, as described above, the movable core is caused by the difference between the urging force of the second urging spring 49 and the urging force of the first urging spring 34. The rod 48 is urged to the suction valve 31 side (right side in FIG. 3) via a guided member 47 integrally formed with the 45.

As a result, the suction valve 31 in contact with the rod 48 is separated from the valve seat portion 32a of the suction valve seat member 32, and the low-pressure fuel chamber 2b and the pressurizing chamber 4 shown in FIG. 2 communicate with each other. Therefore, the fuel in the low-pressure fuel chamber 2b flows into the pressurizing chamber 4 through the gap between the suction valve 31 and the valve seat portion 32a as the plunger 5 descends. Due to the pressure drop of the fuel flowing through the gap between the suction valve 31 and the valve seat portion 32a, a force acts on the suction valve 31 in the valve opening direction (right direction in FIG. 3).

Next, the operation of the discharge process of the high-pressure fuel supply pump 1 will be described. The coil 41 is energized from the ECU 107 (see FIG. 1) in a state where the plunger 5 has exceeded the bottom dead center and has started to rise. A magnetic circuit is formed through the yoke 43, the fixed core 44, the housing 42, and the movable core 45 through which the magnetic flux generated around the coil 41 flows, and a magnetic attraction force is generated between the facing surfaces of the movable core 45 and the fixed core 44. To do. When this magnetic attraction exceeds the difference between the urging force of the second urging spring 49 and the urging force of the first urging valve spring, the movable core 45, together with the guided member 47, joins the movable core 45 and the fixed core 44. The length G1 of the gap between them is displaced, and the movable core 45 comes into contact with the fixed core 44, and the operation of the movable core 45 and the guided member 47 is stopped.

At this time, in the guided member 47 integrally provided with the fitting portion 45a on the inner side in the radial direction of the movable core 45, the inner peripheral surface of the tubular portion 47a slides on the outer peripheral surface of the guide member 46, and the guide member 46 Moves to the fixed core 44 side along the extending direction of. That is, the movement of the movable core 45 to the fixed core 44 side by the magnetic attraction force is guided by the guide member 46 via the guided member 47. As described above, in the present embodiment, the guide member 46 fixed to the fixed core 44 is configured to support and guide the movable core 45 via the guided member 47 integrally provided with the movable core 45. ing.

When the movable core 45 and the guided member 47 are attracted to the fixed core 44 side by the magnetic attraction force, the urging force that separates the suction valve 31 from the valve seat portion 32a disappears, and the urging force of the first urging spring 34 causes the suction valve 31 to be separated from the valve seat portion 32a. The suction valve 31 starts moving toward the valve seat portion 32a. The suction valve 31 displaces the length G2 of the gap between the suction valve 31 and the valve seat portion 32a generated by the difference between the urging force of the second urging spring 49 and the urging force of the first urging spring 34. , The valve is closed.

At this time, the pressure difference between the pressure in the gap space on the pressurizing chamber 4 side (right side in FIG. 3) of the suction valve 31 and the pressure on the suction port 32b side communicating with the low pressure fuel chamber 2b is the pressure difference in the pressurizing chamber 4. As the pressure rises, the pressure in the gap space on the pressurizing chamber 4 side of the suction valve 31 becomes higher than the pressure on the low pressure fuel chamber 2b side, which helps the suction valve 31 to close. After that, when the plunger 5 continues to rise, the volume in the pressurizing chamber 4 decreases and the pressure in the pressurizing chamber 4 rises. As a result, the discharge valve 52 of the discharge valve unit 500 shown in FIG. 2 overcomes the urging force of the discharge valve spring 53 and separates from the discharge valve seat 51, and the fuel passes through the common rail 105 (see FIG. 1) and the injector 103 (see FIG. 1). Is supplied to.

After the suction valve 31 is completely closed, the pressure in the pressurizing chamber 4 rises, and high-pressure discharge is started, the energization of the coil 41 is stopped. As a result, the magnetic attraction force generated between the facing surfaces of the fixed core 44 and the movable core 45 disappears, and the magnetic attraction force becomes smaller than the urging force of the second urging spring 49. Therefore, the urging force of the second urging spring 49 moves the movable core 45, the guided portion, and the movable portion of the rod 48 toward the suction valve 31 side.

At this time, in the guided member 47 provided on the movable core 45, the inner peripheral surface of the tubular portion 47a slides on the outer peripheral surface of the guide member 46, and the suction valve 31 side is along the extending direction of the guide member 46. Move to. That is, the movement of the movable core 45 toward the suction valve 31 by the urging force of the second urging spring 49 is guided by the guide member 46 via the guided member 47.

When the movable core 45, the guided portion, and the movable portion of the rod 48 move and the rod 48 comes into contact with the suction valve 31, the operation (movement) of the movable portion is stopped by the suction valve 31. This is because the valve closing force acting on the suction valve 31 due to the pressure in the pressurizing chamber 4 is larger than the urging force of the second urging spring 49. Therefore, even if the rod 48 pushes the suction valve 31, the suction valve 31 does not open. In this state, the rod 48 prepares to urge the suction valve 31 in the valve opening direction at the moment when the plunger 5 turns from the top dead center to the descending direction.

In the solenoid valve mechanism 300, the flow rate of the fuel discharged at high pressure can be adjusted by controlling the timing of energizing the coil 41 based on the command from the ECU 107. If the energization timing is controlled so that the suction valve 31 closes immediately after the plunger 5 shifts from the bottom dead center to the top dead center, the fuel stays less and the amount of fuel discharged at high pressure increases. it can. As described above, the high-pressure fuel supply pump 1 is configured to control the closing time of the suction valve 31 by controlling the energization time of the coil 41 so that the suction valve 31 can be discharged to a desired flow rate.

The high-pressure fuel supply pump 1 of this embodiment is a high-pressure fuel supply pump 1 having a solenoid valve mechanism 300, and the solenoid valve mechanism 300 is a fixed core 44 and a movable core arranged at a position facing the fixed core 44. A 45, a guide member 46 fixed so as to guide the movable core 45 in a direction in which the movable core 45 is brought into contact with the fixed core 44, and a housing 42 for accommodating the fixed core 44, the movable core 45, and the guide member 46 are provided. The guide member 46 has a brim portion 46c that projects outward in the radial direction, and the brim portion 46c is sandwiched and fixed between the housing 42 and the fixing core 44. That is, it has a brim portion 46c of a guide member 46 that is sandwiched between the bottom portion 42a of the housing 42 and the end portion 44b of the fixing core 44 and fixed by contact. As a result, the axial length of the guide member 46 can be reduced with respect to the press-fitting structure, the solenoid valve mechanism 300 can be miniaturized, and the layout of the high-pressure fuel supply pump 1 is improved.

[Example 2]
The solenoid valve mechanism 300 according to the second embodiment of the present invention will be described with reference to FIG. FIG. 5 is an enlarged view of the solenoid valve mechanism according to the second embodiment of the present invention. The same components as those in the first embodiment are designated by the same reference numerals as those in the first embodiment, and the description thereof will be omitted. Hereinafter, a configuration different from that of the first embodiment will be described.

In this embodiment, the base portion 46a of the guide member 46 is press-fitted into the accommodating portion 44a on the radial inner side of the fixed core 44. In this embodiment, similarly to the first embodiment, the brim portion 46c of the guide member 46 is sandwiched between the bottom portion 42a of the housing 42 and the end portion 44b of the fixing core 44 and is abutted and fixed. Therefore, it is not necessary to increase the axial length of the base portion 46a of the guide member 46, and it is possible to reduce the axial length of the guide member 46.

In this embodiment, in order to secure an air passage that communicates the gap S2 with the opening side of the housing 42, a groove portion 46g extending in the axial direction is provided on the outer peripheral surface 46d of the base portion 46a of the guide member 46. Further, a groove portion 46f extending in the radial direction is provided on the surface of the brim portion 46c of the guide member 46 facing the end portion 44b of the fixed core 44. That is, the guide member 46 has a groove portion 46g extending in the axial direction on the outer peripheral surface 46d of the base portion 46a, and extends in the radial direction on the end surface 46c1 facing the end surface (end surface) 44b of the fixed core 44 of the brim portion 46c. The groove portion 46f is formed, the base portion 46a is press-fitted into the inner peripheral surface (accommodation portion) 44a of the fixed core 44, and the gap S2 communicates with the opening side of the housing 42 through the groove portion 46f and the groove portion 46g.

Other than the above-described configuration, it is the same as that of the first embodiment, and the same action and effect as that of the first embodiment can be obtained. In particular, in this embodiment, since the base portion 46a of the guide member 46 is press-fitted into the housing portion (inner peripheral surface) 44a of the fixed core 44, the axial center of the guide member 46 (center axis A3) and the axial center of the fixed core 44 (center). The alignment of the axis A2) with the axis of the housing 42 (central axis A1) can be facilitated, and the gap between the outer peripheral surface of the movable core 45 and the inner peripheral portion 42b1 of the housing 42 can be reduced. As a result, the magnetic attraction force acting between the fixed core 44 and the movable core 45 can be increased, enabling high-speed operation of the solenoid valve mechanism 300, or reducing the input power required for the operation of the solenoid valve mechanism 300. Can be reduced.

The present invention is not limited to the above-described embodiment, and includes various modifications. The above-described embodiments have been described in detail in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the described configurations. It is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. It is also possible to add, delete, or replace a part of the configuration of each embodiment with another configuration.

For example, the guide member 46 of the above-described embodiment has an integral structure, but may be a guide member having a separate structure.

1 ... High-pressure fuel supply pump, 42 ... Housing, 42a ... Bottom of housing 42, 42b ... Cylindrical part of housing 42, 44 ... Fixed core, 44a ... Inner peripheral surface (accommodation part) of fixed core 44, 45 ... Movable core , 46 ... guide member, 46a ... base of guide member, 46b ... guide body of guide member 46, 46c ... brim of guide member, 46c1 ... end face of fixed core 44 of brim 46c facing end face 44b, 46d ... Outer peripheral surface of the base 46a of the guide member 46, 46f ... groove, 46g ... groove, S1 ... gap, S2 ... gap, 300 ... solenoid valve mechanism.

Claims (5)

A high-pressure fuel supply pump with a solenoid valve mechanism
The solenoid valve mechanism is
With a fixed core
A movable core arranged at a position facing the fixed core,
A guide member fixed so as to guide the movable core in a direction in which the movable core is brought into contact with or separated from the fixed core.
A housing that houses the fixed core, the movable core, and the guide member,
With
The guide member is a high-pressure fuel supply pump having a brim portion that projects outward in the radial direction, and the brim portion is sandwiched and fixed between the housing and the fixed core. In the high-pressure fuel supply pump according to claim 1,
The housing has a bottomed tubular shape having a tubular portion into which the fixed core is press-fitted and a bottom portion of the tubular portion that closes an end opposite to the movable core.
A high-pressure fuel supply pump characterized in that the brim portion is sandwiched between an end portion of the fixed core opposite to the movable core and the bottom portion of the housing. In the high-pressure fuel supply pump according to claim 2.
The guide member has a base portion provided with the brim portion at one end portion, and a guide body provided on the side of the movable core from the other end portion of the base portion and having a diameter smaller than that of the base portion.
A high-pressure fuel supply pump characterized in that the movable core is guided by an end side of the guide body opposite to the base portion. In the high-pressure fuel supply pump according to claim 3,
A high-pressure fuel supply pump having a gap between the inner circumference of the fixed core and the outer circumference of the base portion of the guide member. In the high-pressure fuel supply pump according to claim 3,
The guide member has a groove portion extending in the axial direction on the outer peripheral surface of the base portion, and has a groove portion extending in the radial direction on the end surface of the brim portion facing the end portion of the fixed core. A high-pressure fuel supply pump, characterized in that the base is press-fitted into the inner peripheral surface of the fixed core.

Images