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CN-122014470-A - Flexible integrated needle valve with throttling structure

CN122014470ACN 122014470 ACN122014470 ACN 122014470ACN-122014470-A

Abstract

The invention belongs to the technical field of common rail injectors, and particularly discloses a flexible integrated needle valve with a throttling structure, which comprises the following components: the valve head, the valve tail and the interlude of connecting valve head and valve tail, the interlude is the connecting rod that possesses elastic deformation ability, and the valve tail outside is equipped with a plurality of throttle sections along circumference interval, and the one end surface that the throttle section is close to the connecting rod is equipped with the throttle platform, and each throttle platform is on the circumference at same centre of a circle. According to the invention, the needle valve stably controls the injection of fuel oil and the flow is stable in the transient process of starting or closing the needle valve through the connecting rod and the throttling table.

Inventors

  • ZHAO XING
  • LI YONGKUI
  • LUO YU
  • JIANG YU

Assignees

  • 重油高科电控燃油喷射系统有限公司

Dates

Publication Date
20260512
Application Date
20260324

Claims (10)

  1. 1. A flexible integrated needle valve with a throttling structure is characterized by comprising a valve head (1), a valve tail (2) and a middle section for connecting the valve head (1) and the valve tail (2), wherein the middle section is a connecting rod (3) with elastic deformation capacity, a plurality of throttling sections (21) are arranged at intervals on the outer side of the valve tail (2) along the circumference, throttling platforms (22) are arranged on one end surface of each throttling section (21) close to the connecting rod (3), and all throttling platforms (22) are arranged on the circumference of the same circle center.
  2. 2. Flexible integrated needle valve with throttle structure according to claim 1, characterized in that the connecting rod (3) is welded with the valve head 1 and the valve tail (2) respectively.
  3. 3. Flexible integrated needle valve with throttle structure according to claim 1 or 2, characterized in that the material of the connecting rod (3) is 16CrMn.
  4. 4. The flexible integrated needle valve with the throttling structure according to claim 1 or 2, characterized in that the ratio of the outer diameter to the length of the connecting rod (3) is 1:35-1:25.
  5. 5. Flexible integrated needle valve with throttle structure according to claim 4, characterized in that the ratio of the outer diameter to the length of the connecting rod (3) is 1:30.
  6. 6. The flexible integrated needle valve with a throttle structure according to claim 1, 2 or 5, characterized in that the throttle table (22) is an arc table, the upper surface of the arc table is a plane, and the width of the plane is 0.2-0.6 mm.
  7. 7. The flexible integrated needle valve with throttle structure of claim 6, wherein the width of the flat surface is 0.4mm.
  8. 8. The flexible integrated needle valve with a throttle structure according to claim 6, characterized in that the throttle table (22) has an isosceles trapezoid cross section, and the length of the plane is smaller than the overlapping length of the throttle table (22) and the throttle segment (21).
  9. 9. The flexible integrated needle valve with a throttle structure according to claim 7 or 8, characterized in that the cross-sectional radius of the plane of the throttle table (22) is 0.92 xr to 0.96 xr, r being the cross-sectional radius of the circular arc table.
  10. 10. A flexible integrated needle valve with throttle structure according to claim 1,2,5, 7 or 8, characterized in that the number of throttle segments (21) is three or four, and the surface of the throttle segments (21) is flat or concave.

Description

Flexible integrated needle valve with throttling structure Technical Field The invention belongs to the technical field of common rail fuel injectors, and particularly relates to a flexible integrated needle valve with a throttling structure. Background The high-pressure common rail fuel injection system can realize flexible control of fuel injection timing, fuel injection pulse width, fuel injection rate and injection times of the diesel engine, is recognized as the most advanced fuel injection technology, and is one of the main means for improving the economy of the diesel engine, optimizing the combustion process and reducing harmful emissions at present. The high-voltage common rail system is a complex system of electric-magnetic-mechanical-liquid mutual coupling. Research shows that the pressure fluctuation can be formed in the fuel injector during fuel injection, so that the motion characteristic and injection pressure of the needle valve are unstable, and especially in the transient process of starting or closing the needle valve, the condition that the actual fuel injection quantity is inconsistent with the theoretical control fuel injection quantity can occur, which can deteriorate the working state of the diesel engine, and the concrete steps are as follows: 1. When the needle valve moves axially in the cavity of the needle valve, hydraulic or mechanical impact is applied to the needle valve, so that the needle valve cannot stably control the injection process of fuel. 2. When the needle valve is started, high-pressure fuel flows through the needle valve, the flow speed is extremely high, an instantaneous opening state is formed, and when the needle valve is closed, the flow is rapidly released, the pressure is rapidly attenuated, and the flow opening or closing process is unstable. Disclosure of Invention The invention aims to provide a flexible integrated needle valve with a throttling structure, which can stably control fuel injection and has stable flow in the transient process of starting or closing the needle valve. The invention aims at realizing the technical scheme, and particularly provides a flexible integrated needle valve with a throttling structure, which comprises a valve head, a valve tail and a middle section for connecting the valve head and the valve tail, wherein the middle section is a connecting rod with elastic deformation capability, a plurality of throttling sections are arranged at intervals on the outer side of the valve tail along the circumference, throttling platforms are arranged on the surface of one end, close to the connecting rod, of each throttling section, and each throttling platform is arranged on the circumference of the same circle center. Preferably, the connecting rod is welded to the valve head and the valve tail respectively. Preferably, the material of the connecting rod is 16CrMn. Preferably, the ratio of the outer diameter to the length of the connecting rod is 1:35-1:25. Preferably, the connecting rod has an outer diameter to length ratio of 1:30. Preferably, the throttle table is an arc table, the upper surface of the arc table is a plane, and the width of the plane is 0.2-0.6 mm. Preferably, the width of the plane is 0.4mm. Preferably, the cross section of the throttling table is isosceles trapezoid, and the length of the plane is smaller than the superposition length of the throttling table and the throttling section. Preferably, the plane section radius of the throttling table is 0.92×r-0.96×r, and r is the section radius of the arc table. Preferably, the number of the throttling sections is three or four, and the surfaces of the throttling sections are flat or concave. Due to the adoption of the technical scheme, the invention has the following advantages: The needle valve adopts an integrated structure, eliminates the problems of unreliable fit clearance and force transmission between traditional components, adjusts flow and pressure change by arranging a throttling table in the transition stage of opening or closing fuel injection, slows down abrupt change of the movement speed of the needle valve by elastic expansion or bending deformation of a connecting rod, and improves the stability and reliability of the fuel injection control process by the combined action of the throttling table and the connecting rod. Drawings In order to more clearly illustrate the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described. Throughout the drawings, the elements or portions are not necessarily drawn to actual scale. FIG. 1 is a schematic view of a flexible integrated needle valve with a throttle structure according to the present invention; FIG. 2 is a schematic diagram of a high pressure common rail injector; FIG. 3 is an enlarged schematic view at A; FIG. 4 is a schematic view of a needle valve partially lifted; Fig. 5 is a schematic view showing the needle valve fully lifted. Refere