Solenoid valve mechanism and fuel pump

Abstract

The present invention suppresses wear of a rod or a member in contact with the rod. An electromagnetic suction valve mechanism (solenoid valve mechanism) includes a suction valve (valve body), a rod engaged with the suction valve, and a magnetic attraction force generating portion generating a magnetic attraction force for moving the rod in an axial direction. The rod is provided with a low friction portion. The low-friction portion is set to a friction coefficient such that a friction force generated between the rod and a rod contact member in contact with the rod is smaller than a rotational propulsive force of the rod.

Description

Technical Field

[0001] The present invention relates to a solenoid valve mechanism and a fuel pump having the solenoid valve mechanism. Background Art

[0002] As a solenoid valve mechanism for a fuel pump, for example, there is one described in Patent Document 1. The solenoid valve mechanism (solenoid draft) described in Patent Document 1 presses a rubber material into a receiving portion provided in a fixed core. The rubber material cushions the impact caused by cavitation rupture generated in the fixed core. As a result, the generation of cavitation / erosion is suppressed. Prior art literature Patent Literature

[0003] Patent Document 1: International Publication No. 2020 / 100398 Summary of the invention Technical problem to be solved by the invention

[0004] However, in the solenoid valve mechanism described in Patent Document 1, the housing portion of the fixed core formed of a metal material is filled with fuel. Therefore, cavitation and erosion cannot be suppressed in the entire housing portion of the fixed core.

[0005] In view of the above problems, an object of the present invention is to provide a solenoid valve mechanism and a fuel pump capable of suppressing cavitation and erosion occurring in a fixed core. Technical means for solving technical problems

[0006] In order to solve the above technical problems and achieve the purpose of the present invention, the solenoid valve mechanism of the present invention includes a valve body, a rod engaged with the valve body, a movable core engaged with the rod, a fixed core that generates a magnetic attraction between the movable cores, and a rod force spring that applies force to the rod in a direction away from the fixed core. The fixed core has: a first recess having a bottom surface that abuts against one end of the rod force spring; a second recess formed on the bottom surface of the first recess; and an elastic member that is accommodated in the second recess. The elastic member covers the entire inner wall surface of the second recess.

[0007] In addition, the fuel pump of the present invention includes: a main body, which includes a pressurizing chamber; a plunger, which is supported by the main body for reciprocating movement and increases or decreases the capacity of the pressurizing chamber through reciprocating movement; and the above-mentioned solenoid valve mechanism, which discharges fuel into the pressurizing chamber. Effects of the Invention

[0008] According to the solenoid valve mechanism and the fuel pump having the above-described structure, cavitation and erosion occurring in the fixed core can be suppressed. Other problems, structures, and effects than those described above will become more apparent through the following description of the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is an overall configuration diagram of a fuel supply system using the high-pressure fuel supply pump according to the first embodiment of the present invention. Figure 2 It is a longitudinal sectional view of the high-pressure fuel supply pump according to the first embodiment of the present invention. Figure 3 This is a horizontal cross-sectional view of the high-pressure fuel supply pump according to the first embodiment of the present invention as viewed from above. Figure 4 It is from Figure 2 A longitudinal cross-sectional view of the high-pressure fuel supply pump according to the first embodiment of the present invention, viewed from a different direction. Figure 5 It is a longitudinal sectional view of the solenoid valve mechanism according to the first embodiment of the present invention. Fig. 6A , B is a diagram showing a mechanism of cavitation / erosion occurring in the recessed portion of the fixed core when the fixed core and the movable core are in contact with each other. Fig. 7A , B is a diagram showing a mechanism of cavitation / erosion occurring in the recessed portion of the fixed core when the fixed core and the movable core are in contact with each other. Fig. 8A , B is a diagram showing a mechanism of cavitation / erosion occurring in the recessed portion of the fixed core when the fixed core and the movable core are separated. Fig.9A , B is a diagram showing a mechanism of cavitation / erosion occurring in the recessed portion of the fixed core when the fixed core and the movable core are separated. Fig. 10A , B is a conceptual diagram showing a vibration-type cavitation test device and a diagram showing test results. Fig.11 It is an enlarged longitudinal sectional view of a fixed core of the solenoid valve mechanism according to the first embodiment of the present invention. Fig.12 It is an enlarged longitudinal sectional view of a fixed core of the solenoid valve mechanism according to Embodiment 2 of the present invention. Fig.13 It is an enlarged longitudinal sectional view of a fixed core of the solenoid valve mechanism according to the third embodiment of the present invention. Fig.14 It is an enlarged longitudinal sectional view of a fixed core of a solenoid valve mechanism according to a fourth embodiment of the present invention. DETAILED DESCRIPTION

[0010] 1. Implementation Method 1 Hereinafter, a solenoid valve mechanism and a high-pressure fuel supply pump according to Embodiment 1 of the present invention will be described. In the drawings, the same reference numerals are given to common components.

[0011] [Fuel supply system] First, use Figure 1 A fuel supply system using the high-pressure fuel supply pump (fuel pump) according to the present embodiment will be described. Figure 1 It is an overall configuration diagram of a fuel supply system using the high-pressure fuel supply pump according to the present embodiment.

[0012] like Figure 1 As shown, the fuel supply system includes a high-pressure fuel supply pump (fuel pump) 100, an ECU (Engine Control Unit) 101, a fuel tank 103, a common rail 106, and a plurality of injectors 107. The components of the high-pressure fuel supply pump 100 are integrally assembled in a pump body 1 (hereinafter referred to as "body 1").

[0013] Fuel in the fuel tank 103 is drawn by a feed pump 102 driven based on a signal from the ECU 101. The drawn fuel is pressurized to an appropriate pressure by a pressure regulator (not shown) and sent to the low-pressure fuel suction port 51 of the high-pressure fuel supply pump 100 through the low-pressure pipe 104.

[0014] The high-pressure fuel supply pump 100 pressurizes the fuel supplied from the fuel tank 103 and pressure-feeds it to the common rail 106. A plurality of injectors 107 and a fuel pressure sensor 105 are mounted on the common rail 106.

[0015] The plurality of injectors 107 are installed in accordance with the number of cylinders (combustion chambers). The plurality of injectors 107 inject fuel according to the drive current output from the ECU 101. The fuel supply system of this embodiment is a so-called direct injection engine system in which the injectors 107 inject fuel directly into the cylinders of the engine.

[0016] The fuel pressure sensor 105 outputs the detected pressure data to the ECU 101. The ECU 101 calculates the appropriate injection fuel amount (target injection fuel length), the appropriate fuel pressure (target fuel pressure), etc. based on the engine state quantities (e.g., crank angle, throttle opening, engine speed, fuel pressure, etc.) obtained from various sensors.

[0017] The ECU 101 controls the driving of the high-pressure fuel supply pump 100 and the plurality of injectors 107 based on the calculation results of the fuel pressure (target fuel pressure) etc. That is, the ECU 101 includes a pump control unit for controlling the high-pressure fuel supply pump 100 and an injector control unit for controlling the injectors 107.

[0018] The high-pressure fuel supply pump 100 includes a pressure pulsation reduction mechanism 9, an electromagnetic suction valve mechanism (electromagnetic valve mechanism) 3 as a capacity variable mechanism, and a relief valve mechanism 4 (see Figure 2 ) and the discharge valve mechanism 8. The fuel flowing in from the low-pressure fuel suction port 51 reaches the suction port 31b of the electromagnetic suction valve mechanism 3 via the pressure pulsation reduction mechanism 9 and the suction passage 10b.

[0019] The fuel flowing into the electromagnetic suction valve mechanism 3 passes through the suction valve 32 and flows through the suction passage 1a formed in the main body 1, and then flows into the pressurizing chamber 11. The plunger 2 is slidably held in the pressurizing chamber 11. The plunger 2 is moved by the cam 91 (refer to Figure 2 ) to transmit power and reciprocate.

[0020] In the pressurizing chamber 11, fuel is sucked from the electromagnetic suction valve mechanism 3 during the descending stroke of the plunger 2, and the fuel is pressurized during the ascending stroke. If the fuel pressure in the pressurizing chamber 11 exceeds a predetermined value, the discharge valve mechanism 8 opens, and the high-pressure fuel is pressure-sent to the common rail 106 through the fuel discharge port 12a. The fuel discharge of the high-pressure fuel supply pump 100 is operated by the opening and closing of the electromagnetic suction valve mechanism 3. Moreover, the opening and closing of the electromagnetic suction valve mechanism 3 is controlled by the ECU 101.

[0021] [High-pressure fuel supply pump] Next, we will use Figure 2 to Figure 4 The structure of the high-pressure fuel supply pump 100 will be described. Figure 2 2 is a longitudinal sectional view of the high-pressure fuel supply pump 100 . Figure 3 It is a horizontal cross-sectional view viewed on a cross section perpendicular to the vertical direction of the high-pressure fuel supply pump 100 . Figure 4 It is from Figure 2 Longitudinal cross-sectional views of the high-pressure fuel supply pump 100 as viewed from different directions.

[0022] like Figure 2 and Figure 3 As shown, the main body 1 of the high pressure fuel supply pump 100 is provided with the above-mentioned suction passage 1a and the mounting flange 1b (refer to Figure 3 ). The mounting flange 1b is in close contact with the fuel pump mounting portion 90 of the engine (internal combustion engine). The mounting flange 1b is fixed to the fuel pump mounting portion 90 by a plurality of bolts (screws) not shown. That is, the high-pressure fuel supply pump 100 is fixed to the fuel pump mounting portion 90 via the mounting flange 1b.

[0023] like Figure 2 and Figure 4 As shown, an O-ring 93 showing a specific example of a sheet-like member is interposed between the fuel pump mounting portion 90 and the body 1. The O-ring 93 prevents the engine oil from leaking to the outside of the engine (internal combustion engine) through between the fuel pump mounting portion 90 and the body 1.

[0024] In addition, a cylinder 6 for guiding the reciprocating motion of the plunger 2 is mounted on the main body 1 of the high-pressure fuel supply pump 100. The cylinder 6 is formed in a cylindrical shape. The outer periphery of the cylinder 6 is pressed into a cylinder receiving recess provided on the main body 1. The main body 1 and the cylinder 6 are connected with the electromagnetic suction valve mechanism 3, the plunger 2, and the discharge valve mechanism 8 (see Figure 3 ) together form a pressurized chamber 11.

[0025] The main body 1 is provided with a fixing portion 1c that engages with the central portion of the cylinder 6 in the axial direction. The fixing portion 1c of the main body 1 is oriented upward ( Figure 2 The cylinder 6 is pressed by the upper end surface of the cylinder 6 (in the upper part). Thus, the fuel pressurized in the pressurizing chamber 11 can be prevented from leaking from between the upper end surface of the cylinder 6 and the main body 1.

[0026] The tappet 92 is provided at the lower end of the plunger 2. The tappet 92 converts the rotational motion of the cam 91 mounted on the camshaft of the engine into an up-and-down motion and transmits it to the plunger 2. The plunger 2 is urged toward the cam 91 side by the spring 16 via the retainer 15. As a result, the lower end of the plunger 2 is pressed against the tappet 92. The tappet 92 reciprocates as the cam 91 rotates. The plunger 2 reciprocates together with the tappet 92, thereby changing the volume of the pressurized chamber 11.

[0027] The seal holder 17 is disposed between the cylinder 6 and the retainer 15. The seal holder 17 is formed in a cylindrical shape to be inserted into the plunger 2. A sub chamber 17a is formed between the upper portion of the seal holder 17 and the body 1. In addition, the seal holder 17 retains the plunger seal 18 at the lower end portion on the retainer 15 side.

[0028] The plunger seal 18 is slidably in contact with the outer periphery of the plunger 2. When the plunger 2 reciprocates, the plunger seal 18 seals the fuel in the sub-chamber 17a, thereby preventing the fuel in the sub-chamber 17a from flowing into the engine. In addition, the plunger seal 18 prevents lubricating oil (including engine oil) for lubricating sliding parts in the engine from flowing into the body 1.

[0029] exist Figure 2 In the embodiment, the plunger 2 reciprocates in the up-down direction. If the plunger 2 descends, the volume of the pressurized chamber 11 increases, and if the plunger 2 ascends, the volume of the pressurized chamber 11 decreases. In other words, the plunger 2 is configured to reciprocate in the direction of increasing and decreasing the volume of the pressurized chamber 11.

[0030] The plunger 2 has a large diameter portion 2a and a small diameter portion 2b. When the plunger 2 reciprocates, the large diameter portion 2a and the small diameter portion 2b are located in the auxiliary chamber 17a. Therefore, the volume of the auxiliary chamber 17a increases or decreases by the reciprocating motion of the plunger 2.

[0031] The auxiliary chamber 17a is connected to the fuel passage 10c (see Figure 3) is connected to the low-pressure fuel chamber 10. When the plunger 2 descends, a flow of fuel is generated from the sub-chamber 17a to the low-pressure fuel chamber 10. When the plunger 2 rises, a flow of fuel is generated from the low-pressure fuel chamber 10 to the sub-chamber 17a. As a result, the fuel flow rate to the inside and outside of the pump during the suction stroke or return stroke of the high-pressure fuel supply pump 100 can be reduced. As a result, the pressure pulsation generated inside the high-pressure fuel supply pump 100 can be reduced.

[0032] like Figure 3 and Figure 4 As shown, a suction joint 5 is installed on the side of the main body 1. The suction joint 5 is connected to the low-pressure pipe 104 (see Figure 1 ), the low-pressure piping 104 allows the fuel supplied from the fuel tank 103 to pass through. The fuel in the fuel tank 103 is supplied to the interior of the high-pressure fuel supply pump 100 from the suction joint 5.

[0033] The suction joint 5 has a low-pressure fuel suction port 51 connected to the low-pressure pipe 104 and a suction flow path 52 communicating with the low-pressure fuel suction port 51. Figure 4 As shown in FIG. 1 , a suction filter 53 is arranged in the fuel passage connected to the suction flow passage 52. The suction filter 53 removes foreign matter present in the fuel and prevents the foreign matter from entering the high-pressure fuel supply pump 100. The fuel passing through the suction flow passage 52 is passed through the pressure pulsation reduction mechanism 9 provided in the low-pressure fuel chamber 10 and the suction passage 10b (see FIG. 1 ). Figure 2 ) reaches the suction port 31b of the electromagnetic suction valve mechanism 3 (refer to Figure 2 ).

[0034] like Figure 2 As shown, a low-pressure fuel chamber 10 is provided in the main body 1 of the high-pressure fuel supply pump 100. The low-pressure fuel chamber 10 is covered by a damping cover 14. The low-pressure fuel chamber 10 is provided with a low-pressure fuel flow path 10a and a suction path 10b. The suction path 10b is connected to the suction port 31b of the electromagnetic suction valve mechanism 3 (see Figure 2 The fuel passing through the low-pressure fuel flow path 10a reaches the suction port 31b of the electromagnetic suction valve 3 via the suction passage 10b.

[0035] The low-pressure fuel flow path 10a is provided with a pressure pulsation reduction mechanism 9. When the fuel flowing into the pressurizing chamber 11 is returned to the suction passage 10b again through the electromagnetic suction valve mechanism 3 in the valve open state (refer to Figure 2 ), pressure pulsation occurs in the low pressure fuel chamber 10. The pressure pulsation reducing mechanism 9 reduces the pressure pulsation generated in the high pressure fuel supply pump 100 from affecting the low pressure pipe 104.

[0036] The pressure pulsation reduction mechanism 9 has a metal diaphragm damper having two corrugated disc-shaped metal plates bonded to its outer periphery. An inert gas such as argon is injected into the metal diaphragm damper. The metal diaphragm damper absorbs or reduces pressure pulsation by expansion / contraction.

[0037] like Figure 3 As shown, the discharge valve mechanism 8 is connected to the outlet side of the pressurizing chamber 11. The discharge valve mechanism 8 is accommodated in the discharge valve chamber 1d formed in the main body 1. The discharge valve mechanism 8 includes a discharge valve seat member 81 and a discharge valve 82 that contacts and separates from the discharge valve seat member 81. In addition, the discharge valve mechanism 8 includes a discharge valve spring 83 that urges the discharge valve 82 toward the discharge valve seat member 81 and a discharge valve stopper 84 that determines the lift amount (movement distance) of the discharge valve 82. The discharge valve stopper 84 and the main body 1 are joined at the abutment portion 85 by welding.

[0038] The discharge valve chamber 1d is a substantially cylindrical space extending in the horizontal direction. One end of the discharge valve chamber 1d communicates with the pressurizing chamber 11. The other end of the discharge valve chamber 1d opens to the side surface of the main body 1. The opening of the other end of the discharge valve chamber 1d is sealed by the discharge valve stopper 84.

[0039] The discharge joint 12 is joined to the main body 1 by a welded portion 12b. The discharge joint 12 has a fuel discharge port 12a. The fuel discharge port 12a is connected to the discharge valve chamber 1d via a discharge passage 1f. The discharge passage 1f extends horizontally inside the main body 1. The fuel discharge port 12a is connected to the common rail 106 (see Figure 1 ).

[0040] When the fuel pressure in the pressurizing chamber 11 is lower than the fuel pressure in the discharge valve chamber 1d, the discharge valve 82 is pressed against the discharge valve seat member 81 by the differential pressure acting on the discharge valve 82 and the force of the discharge valve spring 83. As a result, the discharge valve mechanism 8 is in a closed valve state. On the other hand, when the fuel pressure in the pressurizing chamber 11 is higher than the fuel pressure in the discharge valve chamber 1d and the differential pressure acting on the discharge valve 82 is higher than the force of the discharge valve spring 83, the discharge valve 82 is separated from the discharge valve seat member 81. As a result, the discharge valve mechanism 8 is in an open valve state.

[0041] When the discharge valve mechanism 8 is in the open state, the fuel in the pressurizing chamber 11 flows to the common rail 106 (see FIG. 1 ) through the discharge valve chamber 1d, the discharge passage 1f, and the fuel discharge port 12a of the discharge joint 12. Figure 1 ) is discharged. With the above structure, the discharge valve mechanism 8 functions as a check valve that restricts the flow direction of the fuel.

[0042] like Figure 2 and Figure 3As shown, the main body 1 is provided with a relief valve mechanism 4 communicating with the pressurizing chamber 11. The relief valve mechanism 4 has a relief spring 41, a relief valve holder 42, a relief valve 43, a sheet member 44 and a spring support member 45.

[0043] The sheet member 44 is formed in a bottomed cylindrical shape. The sheet member 44 contains the relief spring 41, the relief valve holder 42, the relief valve 43 and the support member 45. The support member 45 is arranged on the side of the pressurizing chamber 11. The bottom of the sheet member 44 is located on the side opposite to the pressurizing chamber 11. A through hole serving as a fuel passage is formed at the bottom of the sheet member 44.

[0044] One end of the relief spring 41 contacts the spring support member 45. The other end of the relief spring 41 contacts the relief valve holder 42. The relief spring 41 urges the relief valve holder 42 toward the bottom of the sheet member 44. The relief valve 43 is disposed between the relief valve holder 42 and the bottom of the sheet member 44.

[0045] The relief valve 43 is engaged with the relief valve holder 42. The relief valve 43 and the relief valve holder 42 apply force to the bottom side of the sheet member 44. As a result, the relief valve 43 blocks the fuel passage of the sheet member 44. The fuel passage of the sheet member 44 is connected to the discharge passage 1f (see Figure 3 The movement of fuel between the pressurizing chamber 11 (upstream side) and the sheet-like member 44 (downstream side) is cut off by the relief valve 43 being in contact with (adhering to) the sheet-like member 44.

[0046] When the pressure of the fuel in the common rail 106 or the member in front of it becomes high, the fuel on the side of the sheet member 44 presses the relief valve 43. As a result, the relief valve 43 moves against the force of the relief spring 41. As a result, the relief valve mechanism 4 opens, and the fuel in the discharge passage 1f returns to the pressurizing chamber 11 through the fuel passage of the sheet member 44. Therefore, the pressure for opening the relief valve 43 is determined by the force of the relief spring 41.

[0047] The relief valve mechanism 4 of this embodiment communicates with the pressurizing chamber 11, but the present invention is not limited thereto. The relief valve mechanism according to the present invention may communicate with a low-pressure passage (low-pressure fuel suction port 51 or suction passage 10b, etc.), for example.

[0048] [Solenoid suction valve mechanism] Next, refer to Figure 5 The electromagnetic suction valve mechanism 3 will be described. Figure 5 It is an enlarged longitudinal sectional view of the electromagnetic suction valve mechanism 3 of the high-pressure fuel supply pump 100 , and shows the valve-opening state of the electromagnetic suction valve mechanism 3 .

[0049] like Figure 5As shown, the electromagnetic suction valve mechanism 3 is inserted into the lateral hole formed in the main body 1. The electromagnetic suction valve mechanism 3 includes a suction valve seat 31 pressed into the lateral hole formed in the main body 1, a suction valve 32, a rod 33, a rod urging spring 34, an electromagnetic coil 35, and an anchor 36. The suction valve 32 represents a specific example of the valve body involved in the present invention. The anchor 36 represents a specific example of the movable core involved in the present invention.

[0050] The suction valve seat 31 is formed in a cylindrical shape. A seat portion 31a is provided on the inner periphery of the suction valve seat 31. A suction port 31b extending from the outer periphery to the inner periphery is formed in the suction valve seat 31. The suction port 31b communicates with the suction passage 10b in the low pressure fuel chamber 10.

[0051] The suction valve seat 31 has a rod guide 31c through which the rod 33 passes. The rod guide 31c is formed in a cylindrical shape. In addition to the cylindrical hole through which the rod 33 passes, the rod guide 31c is provided with a communication passage 31d that passes in the axial direction. Thus, when the anchor 36 moves in the axial direction, the movement of the fuel in the electromagnetic suction valve mechanism 3 can be prevented.

[0052] A stopper 37 is disposed in the lateral hole formed in the body 1 so as to face the seat portion 31a of the suction valve seat 31. The suction valve 32 is disposed between the stopper 37 and the seat portion 31a. In addition, a valve biasing spring 38 is interposed between the stopper 37 and the suction valve 32. The valve biasing spring 38 biases the suction valve 32 toward the seat portion 31 a .

[0053] The suction valve 32 abuts against the seat portion 31a to close the communication portion between the suction port 31b and the pressurizing chamber 11. As a result, the electromagnetic suction valve mechanism 3 is in a closed valve state. On the other hand, the suction valve 32 abuts against the stopper 37 to open the communication portion between the suction port 31b and the pressurizing chamber 11. As a result, the electromagnetic suction valve mechanism 3 is in an open valve state.

[0054] The rod 33 passes through the rod guide 31c and the anchor 36 of the suction valve seat 31. A rod flange 33a is formed on the rod 33. The rod flange 33a engages with one end of the rod urging spring 34. The other end of the rod urging spring 34 engages with a fixed core 39 surrounding the rod urging spring 34. The rod urging spring 34 urges the suction valve 32 in the valve opening direction as the stopper 37 side via the rod 33.

[0055] The anchor 36 is formed in a substantially cylindrical shape. In addition to the cylindrical hole through which the rod 33 passes, the anchor 36 is provided with a communication passage 36a that passes through in the axial direction. Thus, when the anchor 36 moves in the axial direction, the movement of the fuel in the electromagnetic suction valve mechanism 3 can be prevented.

[0056] One end of the anchor urging spring 40 contacts one axial end of the anchor 36. The other axial end of the anchor 36 faces the end surface of the fixed core 39. The other axial end of the anchor 36 has a flange contact portion that contacts the rod flange portion 33a of the rod 33.

[0057] The other end of the anchor urging spring 40 abuts against the rod guide 31c. The anchor urging spring 40 urges the anchor 36 toward the rod flange 33a side of the rod 33. The movable distance 36e of the anchor 36 is set longer than the movable distance 32e of the suction valve 32. As a result, the suction valve 32 can be reliably abutted against the seat portion 31a (seated). As a result, the electromagnetic suction valve mechanism 3 can be reliably in a closed valve state.

[0058] The fixed core 39 is formed into a bottomed cylindrical shape. That is, the fixed core 39 has a recess extending in the axial direction. The rod urging spring 34 is inserted into the recess of the fixed core 39. The other end of the rod urging spring 34 abuts against the bottom surface of the recess of the fixed core 39. Fig.11 The recessed portion of the fixing core 39 will be described.

[0059] The outer core 310 is connected to the opening of the transverse hole formed in the main body 1. The outer core 310 is formed in a substantially cylindrical shape. The outer peripheral portion of one axial end of the outer core 310 is fitted into the transverse hole formed in the main body 1. The outer core 310 is fixed to the main body 1 by welding.

[0060] The anchor 36 is slidably engaged with the inner periphery of the outer core 310. That is, the anchor 36 is guided to the inner periphery of the outer core 310 and moves in the axial direction (valve opening direction and valve closing direction). The other axial end of the outer core 310 protrudes from the main body 1. The first yoke 320 is embedded in the outer periphery of the other axial end of the outer core 310. The outer core 310 is pressed and fixed on the first yoke 320.

[0061] The first yoke 320 is formed in a bottomed cylindrical shape surrounding the electromagnetic coil 35. The fixed core 39 protrudes from the opening side of the first yoke 320. A fitting hole for fitting with the outer core 310 is formed at the center of the bottom of the first yoke 320.

[0062] The opening of the first yoke 320 is blocked by the second yoke 330. The second yoke 330 is composed of a substantially annular plate. A circular through hole is formed substantially in the center of the second yoke 330. The fixed core 39 passes through the through hole of the second yoke 330. A fixing pin 39a is fixed to a portion of the fixed core 39 protruding from the second yoke 330. The fixing pin 39a applies force to the second yoke 330 toward the anchor 36 side.

[0063] The first yoke 320 and the second yoke 330 form a magnetic circuit. The second yoke 330 is formed of the same material as the first yoke 320. As the material of the first yoke 320 and the second yoke 330, for example, a magnetic stainless steel material can be cited.

[0064] The electromagnetic coil 35 is arranged inside the first magnetic yoke 320 so as to be wound around the fixed core 39. The electromagnetic coil 35 is composed of a copper wire wound multiple times around a wire tube 35a. The terminal member 30 (see Figure 2 ). Current flows through the electromagnetic coil 35 via the terminal member 30.

[0065] In the de-energized state where no current flows through the electromagnetic coil 35, the rod 33 is urged in the valve opening direction by the force of the rod urging spring 34, pressing the suction valve 32 in the valve opening direction. As a result, the suction valve 32 leaves the seat portion 31a and abuts against the stopper 37, and the electromagnetic suction valve mechanism 3 is in the valve opening state. In other words, the electromagnetic suction valve mechanism 3 is a normally open type that opens the valve in the de-energized state.

[0066] The terminal member 30 is disposed in a recessed portion of the connector 30a (see Figure 2 ). The connector 30a is integrally molded with the terminal member 30 and the electromagnetic coil 35. The connector 30a passes through the cutout portion of the first magnetic yoke 320. The lower portion of the connector 30a faces the second magnetic yoke 330. The second magnetic yoke 330 has a cutout for avoiding interference with the connector 30a.

[0067] A seal 340 is provided on the inner peripheral side of the electromagnetic coil 35. The seal 340 is formed in a cylindrical shape. The outer core 310 is inserted into one axial end of the seal 340. The fixed core 39 is inserted into the other axial end of the seal 340.

[0068] The outer peripheral surfaces of the fixed core 39 and the outer core 310 form the same peripheral surface as the outer peripheral surface of the seal 340 when the seal 340 is inserted. This makes it easy to mount other components such as the wire tube 35a.

[0069] The seal 340 is formed of a thin and deformable (expandable) material. The elongation of the seal 340 is greater than that of the fixed core 39 and the anchor 36. The seal 340 has an elongation of, for example, 35% or more. In addition, the seal 340 is a non-magnetic body. As a material for the seal 340, for example, austenitic stainless steel is preferred.

[0070] If the electromagnetic suction valve mechanism 3 is in the valve open state, the fuel in the suction port 31b flows into the pressurized chamber 11 through the space between the suction valve 32 and the seat 31a, and through the plurality of fuel passage holes (not shown) of the stopper 37 and the suction passage 1a. In the valve open state of the electromagnetic suction valve mechanism 3, the suction valve 32 contacts the stopper 37, so that the position of the suction valve 32 in the valve opening direction is restricted. In the valve open state of the electromagnetic suction valve mechanism 3, the gap between the suction valve 32 and the seat 31a is the movable distance 32e of the suction valve 32, which becomes the valve opening stroke.

[0071] When current flows through the electromagnetic coil 35, magnetic flux is generated. The generated magnetic flux passes through the fixed core 39, the second magnetic yoke 330, the first magnetic yoke 320, the outer core 310, and the anchor 36 as a magnetic circuit. Then, the magnetic attraction acts on the magnetic attraction surface S of each of the anchor 36 and the fixed core 39. As a result, the anchor 36 moves against the force of the rod urging spring 34 and contacts the fixed core 39.

[0072] When the anchor 36 moves toward the fixed core 39 side, that is, in the valve closing direction, the rod 33 engaged with the anchor 36 moves together with the anchor 36. As a result, the suction valve 32 is released from the force in the valve opening direction and moves in the valve closing direction by the force of the valve biasing spring 38. Furthermore, when the suction valve 32 contacts the seat portion 31a of the suction valve seat 31, the electromagnetic suction valve mechanism 3 is in the valve closing state.

[0073] [Operation of the high-pressure fuel supply pump] Next, use Figure 2 The operation of the high-pressure fuel pump according to the present embodiment will be described.

[0074] exist Figure 2 In the embodiment, when the plunger 2 descends, if the electromagnetic suction valve mechanism 3 opens, the fuel flows from the suction passage 1a into the pressurizing chamber 11. Hereinafter, the stroke of the plunger 2 descending is referred to as the suction stroke. On the other hand, when the plunger 2 ascends, if the electromagnetic suction valve mechanism 3 closes, the fuel in the pressurizing chamber 11 is pressurized. As a result, the fuel in the pressurizing chamber 11 passes through the discharge valve mechanism 8 and is pressure-fed to the common rail 106 (see FIG. 1 ). Figure 1 ) Hereinafter, the process of the plunger 2 rising is referred to as a compression stroke.

[0075] If the electromagnetic suction valve mechanism 3 is closed during the compression stroke, the fuel sucked into the pressurizing chamber 11 during the suction stroke is pressurized and discharged to the common rail 106. On the other hand, if the electromagnetic suction valve mechanism 3 is opened during the compression stroke, the fuel in the pressurizing chamber 11 is pressed back to the suction passage 1a side and is not discharged to the common rail 106. Thus, the discharge of the fuel of the high-pressure fuel supply pump 100 is operated by the opening and closing of the electromagnetic suction valve 3. Moreover, the opening and closing of the electromagnetic suction valve mechanism 3 is controlled by the ECU 101.

[0076] During the suction stroke, the volume of the pressurizing chamber 11 increases, and the fuel pressure in the pressurizing chamber 11 decreases. As a result, the fuel pressure in the pressurizing chamber 11 is lower than the fuel pressure in the suction port 31b. Moreover, when the force generated by the differential pressure between the two exceeds the force generated by the valve biasing spring 38, the suction valve 32 moves away from the seat 31a. As a result, the electromagnetic suction valve mechanism 3 is in a closed valve state. As a result, the fuel on the suction port 31b side flows into the pressurizing chamber 11 through the plurality of holes provided on the stopper 37 between the suction valve 32 and the seat 31a.

[0077] After the suction stroke is completed, the process shifts to the compression stroke. At this time, the electromagnetic coil 35 remains in a non-energized state, and the magnetic attraction does not act between the anchor 36 and the fixed core 39. Moreover, a force in the valve opening direction corresponding to the difference between the forces of the anchor urging spring 40 and the rod urging spring 34 is applied to the suction valve 32. In addition, the fluid force (pressing force in the valve closing direction) generated when the fuel flows back from the pressurized chamber 11 to the low-pressure fuel flow path 10a is applied to the suction valve 32.

[0078] In this state, in order to keep the electromagnetic suction valve mechanism 3 in the valve open state, the difference in force between the anchor urging spring 40 and the rod urging spring 34 is set to be greater than the fluid force. The volume of the pressurizing chamber 11 decreases as the plunger 2 rises. Therefore, the fuel sucked into the pressurizing chamber 11 passes between the suction valve 32 and the suction valve seat 31 and returns to the suction port 31b. Therefore, the fuel pressure inside the pressurizing chamber 11 does not rise. This stroke is called a return stroke.

[0079] In the return trip, if the ECU 101 (refer to Figure 1 ) is applied to the electromagnetic suction valve mechanism 3, and current flows to the electromagnetic coil 35 via the terminal member 30. If current flows through the electromagnetic coil 35, the magnetic attraction acts on the magnetic attraction surface S of the fixed core 39 and the anchor 36, and the anchor 36 is attracted to the fixed core 39.

[0080] Furthermore, when the magnetic attraction force is greater than the force of the rod urging spring 34, the anchor 36 overcomes the force of the rod urging spring 34 and moves toward the fixed core 39 side (valve closing direction). As a result, the rod 33 engaged with the anchor 36 moves in a direction away from the suction valve 32. As a result, the suction valve 32 is seated on the seat portion 31a due to the force of the valve urging spring 38 and the fluid force generated by the fuel flowing into the suction passage 10b. When the suction valve 32 is seated on the seat portion 31a, the electromagnetic suction valve mechanism 3 is in a valve closing state.

[0081] After the electromagnetic suction valve mechanism 3 is in the closed valve state, the fuel in the pressurizing chamber 11 is pressurized as the plunger 2 rises. When the pressure reaches a predetermined pressure or above, the fuel in the pressurizing chamber 11 is discharged to the common rail 106 (see Figure 1 ). This stroke is called the discharge stroke. That is, the compression stroke from the lower starting point to the upper starting point of the plunger 2 is composed of a return stroke and a discharge stroke. Moreover, by controlling the timing of power supply to the electromagnetic coil 35 of the electromagnetic suction valve mechanism 3, the amount of high-pressure fuel discharged can be controlled.

[0082] If the timing of energizing the electromagnetic coil 35 is made earlier, the proportion of the return stroke in the compression stroke becomes smaller, and the proportion of the discharge stroke becomes larger. As a result, the amount of fuel returned to the intake passage 10b becomes less, and the amount of fuel discharged at high pressure becomes more. On the other hand, if the timing of energizing the electromagnetic coil 35 is made later, the proportion of the return stroke in the compression stroke becomes larger, and the proportion of the discharge stroke becomes smaller. As a result, the amount of fuel returned to the intake passage 10b becomes more, and the amount of fuel discharged at high pressure becomes less. Therefore, by controlling the timing of energizing the electromagnetic coil 35, the amount of fuel discharged at high pressure can be controlled to the amount required by the engine (internal combustion engine).

[0083] [Cavitation / erosion on the stationary core] Next, cavitation and erosion occurring in the recessed portion of the fixed core 39 will be described with reference to FIGS. 6 to 9 .

[0084] (When the fixed core and the movable core are in contact) First, cavitation and erosion occurring in the recessed portion of the fixed core 39 when the fixed core 39 and the anchor 36 come into contact with each other will be described with reference to FIGS. 6 and 7 . Fig. 6A The diagram shows a state where the fixed core 39 and the anchor 36 are in the separated positions. Figure 6B This is a diagram showing the moment when the anchor 36 and the fixed core 39 come into contact with each other. Fig. 7A This is a diagram showing a state where the anchor 36 and the fixed core 39 are in contact with each other and cavitation occurs. Figure 7B This is a diagram showing a state where erosion occurs.

[0085] like Fig. 6A As shown, by energizing the electromagnetic coil 35, a magnetic attraction force is generated on the magnetic attraction surface S of the fixed core 39 and the anchor 36. As a result, the anchor 36 moves in a direction close to the fixed core 39 ( Fig. 6A left direction).

[0086] When the anchor 36 approaches the fixed core 39, the fluid (fuel) between the anchor 36 and the fixed core 39 flows into the communication path 36a of the anchor 36 and the recessed portion of the fixed core 39 (hereinafter, the recessed portion of the fixed core 39 is referred to as the "fixed core recessed portion"). At this time, there is no escape path for the fluid in the region V near the bottom surface of the fixed core recessed portion. As a result, the fuel in the region V becomes high pressure.

[0087] like Figure 6B As shown, when the anchor 36 moves in a direction approaching the fixed core 39, the anchor 36 collides with the fixed core 39. As a result, the movement of the anchor 36 stops, and the anchor 36 is brought into contact with the fixed core 39.

[0088] When the anchor 36 stops, the fluid stops flowing into the fixed core recess, and the high-pressure fluid in the fixed core recess flows out from the fixed core recess to the communication path 36a of the anchor 36. As a result, the pressure of the fluid in the region V of the fixed core recess gradually decreases.

[0089] like Fig. 7A As shown, the fluid in the fixed core recess continues to flow out to the communication path 36a side by inertial force. As a result, the pressure of the fluid in the region V of the fixed core recess continues to decrease. Moreover, when the pressure of the fluid in the region V is lower than the saturated vapor pressure, cavitation C is generated in the region V of the fixed core recess.

[0090] like Figure 7B As shown, the pressure of the fluid in the cavitation region V is then restored. This is caused by the pressure wave generated by the fluid flowing out of the fixed core recess colliding with the surrounding components and reflecting, or by the fluid flowing back into the fixed core recess due to the lowering of the pressure of the fluid in the fixed core recess.

[0091] When the fluid pressure in the region V of the fixed core recess is restored, the cavitation C generated in the region V of the fixed core recess is broken. As a result, the fixed core 39 is broken due to the impact force when the cavitation is broken, and erosion E is generated.

[0092] (When the fixed core and the movable core are separated) Next, cavitation and erosion occurring in the recessed portion of the fixed core 39 when the fixed core 39 and the anchor 36 are separated will be described with reference to FIGS. 8 and 9 . Fig. 8A This is a diagram showing a state in which the fixed core 39 and the anchor 36 are in contact with each other. Figure 8B This is a diagram showing a state where the anchor 36 is in the process of leaving the fixed core 39 . Fig.9A This is a diagram showing a state where cavitation occurs when the anchor 36 is in the middle of leaving the fixed core 39 . Fig. 9B This is a diagram showing a state where erosion occurs.

[0093] like Fig. 8A As shown, the anchor 36 is in contact with the fixed core 39, and before the anchor 36 leaves the fixed core 39, there is no volume change near the fixed core recess inside the electromagnetic suction valve mechanism 3. Therefore, there is no pressure change in the fluid in the region V of the fixed core recess. As a result, the fluid is in a static pressure state.

[0094] like Figure 8B As shown, when the anchor 36 moves away from the fixed core 39 (rightward in FIG. 8 ), the fluid flows from the communication path 36a and the fixed core recess into between the fixed core 39 and the anchor 36. As a result, the pressure of the fluid in the region V of the fixed core recess decreases.

[0095] like Fig.9A As shown in FIG. 1 , if the pressure of the fluid in the region V of the fixed core recess continues to decrease, the pressure of the fluid in the region V becomes lower than the saturated vapor pressure. Thus, cavitation C is generated in the region V of the fixed core recess.

[0096] like Fig. 9B As shown, the pressure of the fluid in the cavitation-generated region V is then restored. This is caused by a pressure wave generated when the anchor 36 stops moving, or by a re-inflow of the fluid into the stationary core recess due to a decrease in the pressure of the fluid in the stationary core recess.

[0097] When the pressure of the fluid in the region V of the fixed core recess is restored, the cavitation C generated in the region V of the fixed core recess is broken. As a result, the fixed core 39 is broken due to the impact force when the cavitation is broken, and erosion E is generated.

[0098] The greater the moving speed of the anchor 36, the more severe the environment of cavitation / erosion is to the region V of the recessed portion of the fixed core. On the other hand, in recent years, it is desired to increase the discharge pressure and flow rate of high-pressure fuel pumps. Therefore, it is necessary to increase the lift amount of the cam 91. Moreover, the moving speed of the anchor 36 is qualitatively related to the lift amount of the cam 91. Therefore, in order to cope with the high discharge pressure and flow rate of the high-pressure fuel pump, it is necessary to improve the toughness of the region V of the recessed portion of the fixed core against cavitation / erosion.

[0099] In recent years, the diversification of fuels has been advancing. On the other hand, fuels with low saturated vapor pressure are prone to cavitation. Therefore, the diversification of fuels requires an improvement in the toughness against cavitation / erosion.

[0100] If cavitation / erosion occurs and the parts of the electromagnetic suction valve mechanism 3 are damaged, there is a possibility that holes will be formed in the parts, causing fuel leakage. In addition, even if there are no holes in the parts, there are cases where the cut parts become foreign matter and cause malfunction of the electromagnetic suction valve mechanism 3. Therefore, it is required to improve the toughness against cavitation / erosion.

[0101] [Corrosion resistance of rubber materials] Next, the corrosion resistance of the rubber material will be described with reference to FIG. 10 . Fig. 10A This is a conceptual diagram of a vibration cavitation test device. Fig. 10B This is a diagram showing the test results using a vibration-type cavitation test device.

[0102] The vibration type cavitation test device generates cavitation by causing pressure fluctuations by longitudinally vibrating the horn 200. The test piece 202 faces the front end 201 of the horn 200. The vibration type cavitation test device can confirm the progress of erosion of the test piece 202 due to cavitation.

[0103] The test results under certain test conditions are as follows Fig. 10B shown. Fig. 10B The horizontal axis is hardness (Vickers hardness), Fig. 10B The vertical axis is the incubation period until erosion occurs. Fig. 10B As shown, for materials with a hardness of Hv400 or more, the incubation period is about 40 to 60 minutes. On the other hand, the incubation period of rubber materials is more than 120 minutes, which confirms that they have excellent corrosion resistance. Rubber materials cannot be expressed by Vickers hardness. Therefore, Fig. 10B The incubation period for rubber materials is not depicted.

[0104] [Structure of fixed core] Next, refer to Fig.11 The structure of the fixed core 39 according to the first embodiment will be described. Fig.11 This is an enlarged longitudinal sectional view of the fixed core 39 according to the first embodiment.

[0105] like Fig.11 As shown, the fixed core 39 has a fixed core body 391 and a rubber member 392 mounted on the fixed core body 391. The fixed core body 391 is formed of a metal material into a bottomed cylindrical shape. The fixed core body 391 has a first recess 391a for inserting the rod urging spring 34 and a second recess 391b opened at the bottom surface of the first recess 391a.

[0106] The first recess 391a is formed in a substantially cylindrical shape. The other end of the rod urging spring 34 abuts against the bottom surface of the first recess 391a. The second recess 391b opens at the center of the bottom surface of the first recess 391a. The second recess 391b is opposite to the axial hole of the rod urging spring 34. The second recess 391b is formed in a substantially cylindrical shape.

[0107] The rubber member 392 corresponds to the elastic member involved in the present invention. The rubber member 392 is formed into a substantially cylindrical shape having a diameter substantially the same as that of the second recess 391b. The rubber member 392 is press-fitted and fixed to the second recess 391b. The rubber member 392 covers the entire inner wall surface of the second recess 391b.

[0108] The rubber member 392 is set to have a shape substantially the same as the second recess 391b. The end surface of the rubber member 392 on the rod urging spring 34 side forms the same plane as the bottom surface of the first recess 391a. The rubber member 392 is shaped so as not to contact the bottom surface of the first recess 391a. In other words, the rubber member 392 is not interposed between the bottom surface of the first recess 391a and the rod urging spring 34.

[0109] The rubber member 392 is provided with a recessed portion 392a. The recessed portion 392a is open at the end surface of the rubber member 392 on the rod biasing spring 34 side. Considering the moldability of the rubber material, the recessed portion 392a is formed into a substantially egg shape. The fuel enters the first recessed portion 391a of the fixed core body 391 and the recessed portion 392a of the rubber member 392. On the other hand, the fuel does not enter the second recessed portion 391b of the fixed core body 391.

[0110] In the electromagnetic suction valve mechanism 3 using such a fixed core 39, cavitation and erosion concentrate in the recessed portion 392a of the rubber member 392. Therefore, cavitation and erosion can be suppressed from occurring on the rod urging spring 34 side (first recessed portion 391a) of the rubber member 392.

[0111] In addition, the inner wall surface of the second recess 391b of the fixed core body 391 does not contact the fuel. Therefore, erosion on the inner wall surface of the second recess 391b can be suppressed. Therefore, by installing the rubber member 392 in the second recess 391b, erosion on the fixed core body 391 made of a metal material can be suppressed.

[0112] The bottom surface of the second recessed portion 391b according to the present embodiment is formed as a flat surface. However, in consideration of ease of processing, the bottom surface of the second recessed portion 391b according to the present invention may also be a curved surface or a tapered surface.

[0113] 2. Implementation Method 2 Next, refer to Fig.12 An electromagnetic suction valve mechanism according to a second embodiment of the present invention will be described. Fig.12 This is an enlarged longitudinal sectional view of the fixed core according to the second embodiment.

[0114] The electromagnetic suction valve mechanism 3A according to the second embodiment has the same structure as the electromagnetic suction valve mechanism 3 according to the first embodiment. The electromagnetic suction valve mechanism 3A is different from the electromagnetic suction valve mechanism 3 in the fixed core 39A. Therefore, the fixed core 39A will be described here, and the description of the structure common to the electromagnetic suction valve mechanism 3 will be omitted.

[0115] like Fig.12 As shown in FIG. 1 , the fixed core 39A includes a fixed core body 391 and a rubber member 393 attached to the fixed core body 391. The fixed core body 391 is the same as that of the first embodiment.

[0116] The rubber member 393 corresponds to the elastic member involved in the present invention. The rubber member 393 is formed into a substantially cylindrical shape having a diameter substantially the same as that of the second recess 391b. The rubber member 393 is press-fitted and fixed to the second recess 391b. The rubber member 393 covers the entire inner wall surface of the second recess 391b.

[0117] The rubber member 393 is set to be substantially the same shape as the second recess 391b. The end surface of the rubber member 393 on the rod urging spring 34 side forms the same plane as the bottom surface of the first recess 391a. The rubber member 393 is shaped so as not to contact the bottom surface of the first recess 391a. In other words, the rubber member 393 is not interposed between the bottom surface of the first recess 391a and the rod urging spring 34.

[0118] The rubber member 393 is provided with a recessed portion 393a. The recessed portion 393a is open at the end surface of the rubber member 392 on the rod biasing spring 34 side. The recessed portion 393a is formed in a substantially cylindrical shape. The bottom surface of the recessed portion 393a is formed in a hemispherical curved surface.

[0119] A protrusion 393b protruding toward the opening side is formed at the center of the bottom surface of the recess 393a. The end surface of the protrusion 393b is located in the recess 393a. The position of the protrusion 393b is set in consideration of the insertion position of the mold and nozzle used to mold the rubber member 393. Therefore, the rubber member involved in the present invention only needs to have a recess where cavitation / erosion is concentrated, and the shape of the recess can be appropriately set.

[0120] The fuel enters the first recess 391a of the fixed core body 391 and the recess 393a of the rubber member 393. On the other hand, the fuel does not enter the second recess 391b of the fixed core body 391. In the electromagnetic suction valve mechanism 3A using such a fixed core 39A, cavitation / erosion is concentrated in the recess 393a of the rubber member 393. Therefore, it is possible to suppress the occurrence of cavitation / erosion on the side closer to the rod urging spring 34 than the rubber member 393 (the first recess 391a).

[0121] In addition, the inner wall surface of the second recess 391b of the fixed core body 391 does not contact the fuel. Therefore, erosion on the inner wall surface of the second recess 391b can be suppressed. Therefore, by installing the rubber member 393 on the second recess 391b, erosion on the fixed core body 391 made of a metal material can be suppressed.

[0122] 3. Implementation Method 3 Next, refer to Fig.13 An electromagnetic suction valve mechanism according to a third embodiment of the present invention will be described. Fig.13 This is an enlarged longitudinal sectional view of the fixed core according to the third embodiment.

[0123] The electromagnetic suction valve mechanism 3B according to the third embodiment has the same structure as the electromagnetic suction valve mechanism 3 according to the first embodiment. The electromagnetic suction valve mechanism 3B is different from the electromagnetic suction valve mechanism 3 in the fixed core 39B. Therefore, the fixed core 39B will be described here, and the description of the structure common to the electromagnetic suction valve mechanism 3 will be omitted.

[0124] like Fig.13 As shown, the fixed core 39B has a fixed core body 394 and a rubber member 395 mounted on the fixed core body 394. The fixed core body 394 is formed of a metal material into a bottomed cylindrical shape. The fixed core body 394 has a first recess 394a for inserting the rod urging spring 34, a second recess 394b opened at the bottom surface of the first recess 394a, and a communication port 394c opened at the bottom surface of the second recess 394b.

[0125] The first recess 394a is formed in a generally cylindrical shape. The other end of the rod urging spring 34 is in contact with the bottom surface of the first recess 394a. The second recess 394b is opened in the central portion of the bottom surface of the first recess 394a. The second recess 394b is opposite to the axial hole of the rod urging spring 34. The second recess 394b is formed in a generally cylindrical shape. The connecting port 394c extends to the end surface that reaches the bottom side of the fixed core body 394.

[0126] The rubber member 395 corresponds to the elastic member involved in the present invention. The rubber member 395 is integrally molded with the fixed core body 394 (for example, insert molding). When the fixed core 39B is molded, the rubber material is ejected from the connecting port 394c to the second recess 394b. As a result, the nozzle for ejecting the rubber material does not interfere with the fixed core body 394. As a result, the rubber member 395 can be easily molded.

[0127] The second recessed portion 394b and the communication port 394c are filled with the rubber member 395. Therefore, the rubber member 395 covers the inner wall surface of the second recessed portion 394b and the entire inner wall surface of the communication port 394c.

[0128] The rubber member 395 is set to be substantially the same shape as the second recess 394b and the communication port 394c. The end surface of the rubber member 395 on the rod urging spring 34 side forms the same plane as the bottom surface of the first recess 394a. The rubber member 395 is in a shape that does not contact the bottom surface of the first recess 394a. In other words, the rubber member 395 is not interposed between the bottom surface of the first recess 394a and the rod urging spring 34.

[0129] The rubber member 395 is provided with a recessed portion 395a. The recessed portion 395a is open at the end surface of the rubber member 395 on the rod biasing spring 34 side. Considering the moldability of the rubber material, the recessed portion 395a is formed into a substantially egg shape. The fuel enters the first recessed portion 394a of the fixed core body 394 and the recessed portion 395a of the rubber member 395. On the other hand, the fuel does not enter the second recessed portion 394b of the fixed core body 394 and the communication port 394c.

[0130] In the electromagnetic suction valve mechanism 3B using such a fixed core 39B, cavitation and erosion are concentrated in the recessed portion 395a of the rubber member 395. Therefore, cavitation and erosion can be suppressed from occurring on the rod urging spring 34 side (first recessed portion 394a) of the rubber member 395.

[0131] In addition, the inner wall surface of the second recess 394b of the fixed core body 394 does not contact the fuel. Therefore, erosion on the inner wall surface of the second recess 394b can be suppressed. Therefore, by installing the rubber member 395 in the second recess 394b, erosion on the fixed core body 394 made of a metal material can be suppressed.

[0132] 4. Implementation Method 4 Next, refer to Fig.14 An electromagnetic suction valve mechanism according to a fourth embodiment of the present invention will be described. Fig.14 This is an enlarged longitudinal sectional view of the fixed core according to the fourth embodiment.

[0133] The electromagnetic suction valve mechanism 3C according to the fourth embodiment has the same structure as the electromagnetic suction valve mechanism 3 according to the first embodiment. The difference between the electromagnetic suction valve mechanism 3C and the electromagnetic suction valve mechanism 3 is the fixed core 39C. Therefore, the fixed core 39C will be described here, and the description of the structure common to the electromagnetic suction valve mechanism 3 will be omitted.

[0134] like Fig.14As shown, the fixed core 39C has a fixed core body 396 and a rubber member 397 mounted on the fixed core body 396. The fixed core body 396 is formed of a metal material into a bottomed cylindrical shape. The fixed core body 396 has a first recess 396a into which the rod urging spring 34 is inserted, a second recess 396b opened at the bottom surface of the first recess 396a, and a communication port 396c opened at the bottom surface of the second recess 396b.

[0135] The first recess 396a is formed in a substantially cylindrical shape. The other end of the rod urging spring 34 abuts against the bottom surface of the first recess 396a. The second recess 396b opens at the center of the bottom surface of the first recess 396a. The second recess 396b is opposite to the axial hole of the rod urging spring 34. The second recess 396b is formed in a substantially cylindrical shape.

[0136] The communication port 396c extends to the end surface on the bottom side of the fixed core body 394. The communication port 396c is in the shape of two cylinders of different diameters arranged in the axial direction. The communication port 396c has a large diameter portion opened on the bottom side of the fixed core body 394 and a small diameter portion connected to the large diameter portion and the second recess 396b. The diameter of the large diameter portion is larger than that of the small diameter portion.

[0137] The rubber member 397 corresponds to the elastic member involved in the present invention. The rubber member 397 is integrally formed with the fixed core body 396 (for example, insert molding). When the fixed core 39C is molded, the rubber material is ejected from the connecting port 396c to the second recess 396b. As a result, the nozzle for ejecting the rubber material does not interfere with the fixed core body 394. As a result, the rubber member 397 can be easily molded.

[0138] The large diameter portion on the inlet side (opposite to the second recess 396b) of the communication port 396c is a larger space than the small diameter portion on the second recess 396b side. Therefore, various sizes of nozzles for injecting rubber material can be accommodated.

[0139] The second recessed portion 396b and the communication port 396c are filled with the rubber member 397. Therefore, the rubber member 397 covers the inner wall surface of the second recessed portion 396b and the entire inner wall surface of the communication port 396c.

[0140] The rubber member 397 is set to be substantially the same shape as the second recess 396b and the communication port 396c. The end surface of the rubber member 397 on the rod urging spring 34 side forms the same plane as the bottom surface of the first recess 396a. The rubber member 397 is shaped so as not to contact the bottom surface of the first recess 396a. In other words, the rubber member 397 is not interposed between the bottom surface of the first recess 396a and the rod urging spring 34.

[0141] The rubber member 397 is provided with a recessed portion 397a. The recessed portion 397a is open at the end surface of the rubber member 397 on the rod biasing spring 34 side. Considering the moldability of the rubber material, the recessed portion 397a is formed into a substantially egg shape. The fuel enters the first recessed portion 396a of the fixed core body 396 and the recessed portion 397a of the rubber member 397. On the other hand, the fuel does not enter the second recessed portion 396b of the fixed core body 396 and the communication port 396c.

[0142] In the electromagnetic suction valve mechanism 3C using such a fixed core 39C, cavitation and erosion are concentrated in the recessed portion 397a of the rubber member 397. Therefore, cavitation and erosion can be suppressed from occurring on the rod urging spring 34 side (first recessed portion 394a) of the rubber member 397.

[0143] In addition, the inner wall surface of the second recess 396b of the fixed core body 396 does not contact the fuel. Therefore, erosion of the inner wall surface of the second recess 396b can be suppressed. Therefore, by installing the rubber member 397 in the second recess 396b, erosion of the fixed core body 396 made of a metal material can be suppressed.

[0144] 5. Summary As described above, the electromagnetic suction valve mechanism 3 (electromagnetic valve mechanism) includes the suction valve 32 (valve body), the rod 33 engaged with the suction valve 32, and the anchor 36 (movable core) engaged with the rod 33. In addition, the electromagnetic suction valve mechanism 3 includes: a fixed core 39 that generates a magnetic attraction force between the anchor 36; and a rod urging spring 34 that urges the rod 33 in a direction away from the fixed core 39. The fixed core 39 has: a first recess 391a having a bottom surface that abuts against one end of the rod urging spring 34; a second recess 391b formed on the bottom surface of the first recess 391a; and a rubber member 392 (elastic member) accommodated in the second recess 391b. The rubber member 392 covers the entire inner wall surface of the second recess 391b. Thus, the fuel does not enter the second recessed portion 391b of the fixed core 39. As a result, it is possible to suppress the occurrence of erosion on the inner wall surface of the second recessed portion 391b.

[0145] The rubber member 392 (elastic member) of the electromagnetic suction valve mechanism 3 (electromagnetic valve mechanism) is provided with a recessed portion 392a on the surface that comes into contact with the fuel. Thus, cavitation and erosion are concentrated in the recessed portion 392 a of the rubber member 392 . Therefore, it is possible to suppress the occurrence of cavitation and erosion in the first recessed portion 391 a located on the rod urging spring 34 side of the rubber member 392 .

[0146] The rubber member 392 (elastic member) of the electromagnetic suction valve mechanism 3 (electromagnetic valve mechanism) may protrude toward the rod urging spring 34 side from the bottom surface of the first recessed portion 391 a . Thus, the axial dimension of the rubber member 392 can be made longer than the depth of the second recess 391 b. As a result, the minimum allowable dimension of the rubber member 392 can be made the depth of the second recess 391 b, and the rubber member 392 can be easily manufactured.

[0147] The rubber member 395 (elastic member) of the electromagnetic suction valve mechanism 3B (electromagnetic valve mechanism) is filled in the second recess 394b and is fixed or adhered to the second recess 394b. Thus, the rubber member 395 that covers the entire inner wall surface of the second recessed portion 394 b can be easily formed.

[0148] The rubber member 392 (elastic member) of the electromagnetic suction valve mechanism 3 (electromagnetic valve mechanism) is shaped so as not to come into contact with the bottom surface of the first recessed portion 391 a . Thus, the rubber member 392 can be removed from the bottom surface of the first recess 391a and the rod urging spring 34. As a result, the length of the rod urging spring 34 in the compressed state can be made not shorter than the set length. Therefore, the rod urging spring 34 can urge the anchor 36 with an appropriate urging force.

[0149] The rubber member 392 (elastic member) of the electromagnetic suction valve mechanism 3 (electromagnetic valve mechanism) is shaped so as not to be interposed between the bottom surface of the first recessed portion 391 a and the rod urging spring 34 . This makes it possible to prevent the length of the rod urging spring 34 in the compressed state from being shorter than the set length. As a result, the rod urging spring 34 can urge the anchor 36 with an appropriate urging force.

[0150] The above-mentioned high-pressure fuel supply pump 100 (fuel pump) includes: a main body 1 having a pressurizing chamber 11; a plunger 2 which is reciprocatably supported on the main body 1 and increases or decreases the capacity of the pressurizing chamber 11 through reciprocating motion; and the above-mentioned electromagnetic suction valve mechanism 3 (electromagnetic valve mechanism) which discharges fuel into the pressurizing chamber 11. Thus, the fuel does not enter the second recessed portion 391b of the fixed core 39 in the electromagnetic suction valve mechanism 3. As a result, it is possible to suppress the occurrence of erosion on the inner wall surface of the second recessed portion 391b.

[0151] The above describes the embodiments of the solenoid valve mechanism and the fuel pump of the present invention, including their effects. However, the solenoid valve mechanism and the fuel pump of the present invention are not limited to the above embodiments, and various modifications can be implemented within the scope of the invention described in the claims.

[0152] In addition, the above-mentioned embodiments are detailed descriptions for the purpose of explaining the present invention in an understandable manner, and the present invention is not limited to including all the structures described. In addition, a part of the structure of a certain embodiment may be replaced with the structure of another embodiment, and the structure of another embodiment may be added to the structure of a certain embodiment. In addition, other structures may be added, deleted, or replaced with a part of the structure of each embodiment.

[0153] For example, in the above-mentioned Embodiments 1 and 2, the rubber members 392 and 393 are press-fitted and fixed to the second recess 391b. However, the rubber member (elastic member) according to the present invention may be bonded to the inner wall surface of the second recess using an adhesive material.

[0154] In the above-mentioned embodiment, the elastic member of the present invention is applied as rubber member 392, 393, 395, 397. However, the elastic member of the present invention is not limited to the rubber member, and the material can be appropriately determined as long as it is an elastic member that can buffer the shock wave caused by cavitation rupture. The elastic member of the present invention is preferably a member having a Poisson's ratio of 0.45 or more and 0.55 or less. Description of symbols

[0155] 1…Main body, 2…Plunger, 3, 3A, 3B, 3C…Electromagnetic suction valve mechanism (solenoid valve mechanism), 4…Relief valve mechanism, 5…Suction joint, 6…Cylinder, 8…Discharge valve mechanism, 9…Pressure pulsation reduction mechanism, 10…Low-pressure fuel chamber, 11…Pressurizing chamber, 12…Discharge joint, 14…Damper cover, 15…Retainer, 17…Seal holder, 18…Plunger seal, 30…Terminal member, 31…Suction valve Seat, 31a… Seating portion, 31b… Intake port, 31c… Rod guide, 31d… Communication path, 32… Intake valve, 33… Rod, 33a… Rod flange, 35… Solenoid, 35a… Wire tube, 36… Anchor (movable core), 36a… Communication path, 37… Stopper, 39, 39A, 39B, 39C… Fixed core, 39a… Fixed pin, 51… Low-pressure fuel intake port, 52… Intake flow path , 53…suction filter, 90…fuel pump mounting portion, 91…cam, 92…tappet, 93…O-ring, 100…high pressure fuel supply pump, 101…ECU, 102…feed pump, 103…fuel tank, 104…low pressure piping, 105…fuel pressure sensor, 106…common rail, 107…injector, 200…horn, 201…front end, 202…test piece, 310…outer core, 320… first yoke, 330…second yoke, 340…seal, 391, 394, 396…fixed core body, 391a, 394a, 396a…first recess, 391b, 394b, 396b…second recess, 392, 393, 395, 397…rubber member, 392a, 393a, 395a, 397a…recess, 393b…protrusion, 394c, 396c…connecting port.

Claims

1. A solenoid valve mechanism, comprising: The electromagnetic valve mechanism comprises a valve body, a rod engaged with the valve body, a movable core engaged with the rod, a fixed core generating a magnetic attraction force between the fixed core and the movable core, and a rod urging spring urging the rod in a direction away from the fixed core. The electromagnetic valve mechanism is characterized in that: The fixed core has: a first recess having a bottom surface abutting against one end of the rod urging spring; and a second recess formed on the bottom surface of the first recess; and an elastic member received in the second recess, The elastic member covers the entire inner wall surface of the second recess.

2. The solenoid valve mechanism according to claim 1, characterized in that: The elastic member has a recessed portion on a surface that contacts the fuel.

3. The solenoid valve mechanism according to claim 1, characterized in that: The elastic member protrudes toward the lever urging spring from the bottom surface of the first recessed portion.

4. The solenoid valve mechanism according to claim 1, characterized in that: The elastic member fills the second recess and is fixed or bonded to the second recess.

5. The solenoid valve mechanism according to claim 1, characterized in that: The elastic member has a shape that does not contact the bottom surface of the first recessed portion.

6. The solenoid valve mechanism according to claim 1, characterized in that: The elastic member has a shape not interposed between the bottom surface of the first recess and the lever urging spring.

7. A fuel pump, characterized in that: include: a main body including a pressurized chamber; a plunger supported by the body so as to be reciprocatable and capable of increasing or decreasing the capacity of the pressurizing chamber by reciprocating motion; and a solenoid valve mechanism for discharging fuel into the pressurizing chamber, In the solenoid valve mechanism, The invention comprises a valve body, a rod engaged with the valve body, a movable core engaged with the rod, a fixed core generating a magnetic attraction force between the fixed core and the movable core, and a rod urging spring urging the rod in a direction away from the fixed core. The fixed core has: a first recess having a bottom surface abutting against one end of the rod urging spring; and a second recess formed on the bottom surface of the first recess; and an elastic member received in the second recess, The elastic member covers the entire inner wall surface of the second recess.

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