JP-7857403-B2 - Solenoid valve mechanism and fuel pump

Inventors

• 飯塚 智
• 小俣 繁彦
• 高奥 淳司
• 秋山 壮嗣

Assignees

• Ａｓｔｅｍｏ株式会社

Dates

Publication Date

20260512

Application Date

20220607

Claims (7)

1. In a solenoid valve mechanism comprising a valve body, a rod that engages with the valve body, a movable core that engages with the rod, a fixed core that generates a magnetic attractive force between itself and the movable core, and a rod biasing spring that biases the rod away from the fixed core, The fixed core has a first recess having a bottom surface against which one end of the rod biasing spring abuts, a second recess formed on the bottom surface of the first recess, and an elastic member housed in the second recess. The elastic member is a solenoid valve mechanism that covers the entire inner wall surface of the second recess.
2. The solenoid valve mechanism according to claim 1, wherein the elastic member has a recess on the surface that comes into contact with the fuel.
3. The solenoid valve mechanism according to claim 1, wherein the elastic member protrudes from the bottom surface of the first recess toward the rod biasing spring.
4. The solenoid valve mechanism according to claim 1, wherein the elastic member is filled in the second recess and fixed or bonded to the second recess.
5. The solenoid valve mechanism according to claim 1, wherein the elastic member has a shape that does not contact the bottom surface of the first recess.
6. The solenoid valve mechanism according to claim 1, wherein the elastic member is shaped so that it is not interposed between the bottom surface of the first recess and the rod biasing spring.
7. A body equipped with a pressurized chamber, A plunger is supported on the body so as to be able to reciprocate, and the volume of the pressurizing chamber is increased or decreased by the reciprocating motion, The system includes a solenoid valve mechanism for discharging fuel into the pressurized chamber, The solenoid valve mechanism is, The valve comprises a valve body, a rod that engages with the valve body, a movable core that engages with the rod, a fixed core that generates a magnetic attractive force between itself and the movable core, and a rod biasing spring that biases the rod away from the fixed core. The fixed core has a first recess having a bottom surface against which one end of the rod biasing spring abuts, a second recess formed on the bottom surface of the first recess, and an elastic member housed in the second recess. The elastic member covers the entire inner wall surface of the second recess.

Description

This invention relates to a solenoid valve mechanism and a fuel pump equipped with the solenoid valve mechanism. As an example of a solenoid valve mechanism for a fuel pump, see Patent Document 1. The solenoid valve mechanism (solenoid design) described in Patent Document 1 has a rubber material pressed into a housing provided in a fixed core. The rubber material cushions the impact caused by cavitation collapse occurring within the fixed core. As a result, the occurrence of cavitation erosion is suppressed. International Publication No. 2020/100398 This is an overall configuration diagram of a fuel supply system using a high-pressure fuel supply pump according to the first embodiment of the present invention.This is a longitudinal cross-sectional view of a high-pressure fuel supply pump according to the first embodiment of the present invention.This is a horizontal cross-sectional view of a high-pressure fuel supply pump according to the first embodiment of the present invention, as seen from above.This is a longitudinal cross-sectional view of a high-pressure fuel supply pump according to the first embodiment of the present invention, viewed from a different direction than that shown in Figure 2.This is a longitudinal cross-sectional view of a solenoid valve mechanism according to the first embodiment of the present invention.Figures A and B show the mechanism by which cavitation erosion occurs in the recess of the fixed core when the fixed core and the movable core come into contact.Figures A and B show the mechanism by which cavitation erosion occurs in the recess of the fixed core when the fixed core and the movable core come into contact.Figures A and B show the mechanism by which cavitation erosion occurs in the recess of the fixed core when the fixed core and the movable core are separated.Figures A and B show the mechanism by which cavitation erosion occurs in the recess of the fixed core when the fixed core and the movable core are separated.Figures A and B show a conceptual diagram of a vibrating cavitation testing apparatus and the test results.This is an enlarged longitudinal cross-sectional view of the fixed core of the solenoid valve mechanism according to the first embodiment of the present invention.This is an enlarged longitudinal cross-sectional view of the fixed core of the solenoid valve mechanism according to the second embodiment of the present invention.This is an enlarged longitudinal cross-sectional view of the fixed core of the solenoid valve mechanism according to the third embodiment of the present invention.This is an enlarged longitudinal cross-sectional view of the fixed core of the solenoid valve mechanism according to the fourth embodiment of the present invention. 1. First Embodiment The solenoid valve mechanism and high-pressure fuel supply pump according to the first embodiment of the present invention will be described below. In each figure, common components are denoted by the same reference numerals. [Fuel supply system] First, a fuel supply system using the high-pressure fuel supply pump (fuel pump) according to this embodiment will be described with reference to Figure 1. Figure 1 is an overall diagram of the fuel supply system using the high-pressure fuel supply pump according to this embodiment. As shown in Figure 1, the fuel supply system comprises 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 incorporated into the pump body 1 (hereinafter referred to as "body 1"). Fuel from the fuel tank 103 is drawn up by a feed pump 102, which is driven based on a signal from the ECU 101. The drawn-up fuel is pressurized to an appropriate pressure by a pressure regulator (not shown) and sent through a low-pressure pipe 104 to the low-pressure fuel inlet 51 of the high-pressure fuel supply pump 100. The high-pressure fuel supply pump 100 pressurizes the fuel supplied from the fuel tank 103 and pumps it to the common rail 106. The common rail 106 is equipped with multiple injectors 107 and a fuel pressure sensor 105. Multiple injectors 107 are installed according to the number of cylinders (combustion chambers). The multiple 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 directly inject fuel into the cylinders of the engine. The fuel pressure sensor 105 outputs the detected pressure data to the ECU 101. The ECU 101 calculates the appropriate fuel injection amount (target fuel injection length) and appropriate fuel pressure (target fuel pressure) based on engine state variables obtained from various sensors (e.g., crank rotation angle, throttle opening, engine speed, fuel pressure, etc.). The ECU 101 controls the operation of the high-pressure fuel supply