Lightweight normally open solenoid valve

Abstract

The invention discloses a light-weight normally-open electromagnetic valve, which belongs to the field of electromagnetic valves, and comprises a valve shell, a valve seat and a valve core assembly arranged between the valve shell and the valve seat, the valve core assembly comprises a static iron core fixed in the valve shell, an electromagnetic coil sleeved on the outer side of the static iron core through a coil framework, a movable iron core arranged at the bottom of the static iron core and a spring assembly, the valve is characterized in that the valve shell and the valve seat are both formed by compression molding of a composite material composed of a polyether-ether-ketone matrix and a 3D woven carbon fiber reinforcement, the volume ratio of carbon fibers is 25%-35%, the material density is smaller than or equal to 1.5 g / cm < 3 >, and the tensile strength is larger than or equal to 200 MPa; the movable iron core and the static iron core are both of a hollow cylinder structure. By the adoption of the light-weight normally-open electromagnetic valve, through application of the 3D woven carbon fiber reinforced PEEK composite material, the problem that a traditional plastic valve shell is insufficient in strength is solved, and unification of light weight and high strength is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of solenoid valves, and in particular to a lightweight normally open solenoid valve. Background Art

[0002] The normally open solenoid valve for vehicle brake is mainly used in active safety braking systems such as ABS and ESC. The control system of the active safety braking system controls the output of braking torque by controlling the solenoid valve, so that the vehicle can drive safely and stably.

[0003] Existing normally open solenoid valves use a charged coil to generate a magnetic field, which causes the movable iron core to move downward, closing the valve. When the coil is deenergized, the electromagnetic field disappears, and a spring resets the movable iron core, resetting the valve and opening it. Existing normally open solenoid valves have the following drawbacks: 1. Weight: Traditional solenoid valves, including valve bodies and valve cores, are often made of stainless steel or cast iron, resulting in a high overall weight and limiting their use in weight-sensitive applications. 2. Energy consumption: To overcome the spring resistance and close the valve, a continuous high current is required, wasting energy and easily causing the coil to heat up and age. Summary of the Invention

[0004] The purpose of the present invention is to provide a lightweight normally open solenoid valve to solve the above technical problems.

[0005] To achieve the above-mentioned object, the present invention provides a lightweight normally open solenoid valve, comprising a valve housing, a valve seat, and a valve core assembly arranged between the valve housing and the valve seat. The valve core assembly comprises a static iron core fixed inside the valve housing, an electromagnetic coil sleeved on the outside of the static iron core via a coil skeleton, a movable iron core arranged at the bottom of the static iron core, and a spring assembly. The valve housing and the valve seat are both made of a composite material composed of a polyetheretherketone matrix and a 3D woven carbon fiber reinforcement by molding, and the carbon fiber volume accounts for 25%-35%, and the material density is ≤1.5g / cm 3 , tensile strength ≥ 200MPa;

[0006] Both the moving iron core and the static iron core are hollow cylindrical structures.

[0007] Preferably, a flow channel is provided in the valve seat, a conical sealing head is provided at the bottom end of the moving iron core and at a position corresponding to the flow channel, a conical guide hole is provided on the flow channel and at a position corresponding to the conical sealing head, a spiral guide groove is provided on the inner wall of the conical guide hole, and the depth of the spiral guide groove is 1mm-2mm.

[0008] Preferably, the conical sealing head is made of titanium alloy TC4, which is integrated with the moving iron core by vacuum diffusion welding, and the shear strength of the welding interface is ≥300 MPa.

[0009] Preferably, the contact angle between the conical sealing head and the conical guide hole is 45°±1°, and the surface of the conical guide hole is covered with a tungsten carbide-cobalt alloy coating with a thickness of 0.2-0.4 mm by a plasma spraying process.

[0010] Preferably, the winding of the electromagnetic coil adopts Litz wire with a diameter of 0.1mm-0.15mm, with a turn density of ≥150 turns per square centimeter, and the coil skeleton adopts a hollow structure design with a hollow ratio ≥35%.

[0011] Preferably, the spring assembly is a two-stage spring structure, which includes a first spring arranged between the moving iron core and the valve housing and a second spring arranged between the coil skeleton and the moving iron core, and the elastic coefficient of the first spring is 4-6 times the elastic coefficient of the second spring.

[0012] Preferably, the first spring is made of Ti-6Al-4V, and the second spring is made of 17-7PH stainless steel.

[0013] Preferably, a nickel-phosphorus alloy layer with a thickness of 0.051 mm to 0.1 mm is deposited on the outer surface of the composite material of the valve housing by a chemical plating process, and the surface roughness Ra is ≤ 0.8 μm.

[0014] Therefore, the present invention adopts the above-mentioned lightweight normally open solenoid valve, which has the following beneficial effects:

[0015] 1. The valve housing and valve seat are made of 3D woven carbon fiber reinforced PEEK composite material (carbon fiber volume accounts for 25%-35%), with a density of ≤1.5g / cm 3 , with a tensile strength of ≥200MPa, it is 60%-70% lighter than traditional stainless steel / cast iron materials, while meeting the structural strength requirements under high-pressure conditions (pressure bearing ≥10MPa); both the moving iron core and the static iron core are hollow cylinders, further reducing the amount of metal material used and reducing the weight of core moving parts by more than 40%;

[0016] 2. The inner wall of the tapered guide hole in the valve seat flow channel is provided with a spiral guide groove with a depth of 1-2mm to guide the fluid to form a swirl flow, reduce turbulent loss, reduce the flow resistance coefficient by 20%-30% compared with the traditional straight flow channel, and increase the flow coefficient to above 1.3 (the traditional structure is about 0.9);

[0017] 3. The conical sealing head (titanium alloy TC4) and the moving iron core are formed into a whole through vacuum diffusion welding. The shear strength of the welding interface is ≥300MPa, which eliminates the assembly gap and avoids the leakage risk of traditional threaded connections. The surface of the conical guide hole is sprayed with a 0.2mm-0.4mm tungsten carbide-cobalt alloy coating (hardness ≥HV1200), and the sealing surface wear rate is ≤0.001mm. 3 / N·m, service life extended to more than 10 million times (traditional rubber seals are about 5 million times);

[0018] 4. Dual-spring coordinated control: The first spring (high-rigidity titanium alloy) provides the reset force in the normally open state, and the second spring (low-rigidity stainless steel) assists the electromagnetic force to close the valve, reducing the electromagnetic driving force requirement by more than 40%. The steady-state power consumption is ≤1.5W (conventional solenoid valve ≥5W). Combined with Litz wire winding, it reduces copper and iron losses, achieving significant energy-saving effects.

[0019] 5. The lightweight design with a hollowing rate of ≥35% reduces the coil weight by 30%-40%, while improving the heat dissipation efficiency and the coil temperature rise is ≤35K;

[0020] 6. Corrosion resistance treatment: The outer surface of the composite valve body is electrolessly plated with nickel-phosphorus alloy layer (thickness 0.05mm-0.1mm, roughness Ra≤0.8μm), and has no corrosion after 1000 hours of salt spray test. It is suitable for harsh environments such as humidity, acid and alkali.

[0021] In summary, the present invention achieves breakthroughs in key indicators such as lightweight, low power consumption, response speed, and reliability through material replacement (composite materials + titanium alloy), structural integration (hollow iron core + integrated sealing head) and fluid optimization (spiral guide groove), solving the application bottleneck of traditional normally open solenoid valves in vehicle braking scenarios.

[0022] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A cross-sectional view of a lightweight normally open solenoid valve of the present invention;

[0024] Figure 2 This is an appearance diagram of a lightweight normally open solenoid valve of the present invention.

[0025] Reference numerals

[0026] 1. Static iron core; 2. Valve housing; 3. Coil skeleton; 4. Solenoid coil; 5. Moving iron core; 6. First spring; 7. Second spring; 8. Conical sealing head; 9. Valve seat; 10. Flow channel. DETAILED DESCRIPTION

[0027] In order to make the purposes, technical solutions and advantages disclosed in the embodiments of the present invention clearer, the embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the embodiments of the present invention and are not intended to limit the embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. Examples of the embodiments are shown in the accompanying drawings, where the same or similar numbers throughout represent the same or similar elements or elements with the same or similar functions.

[0028] It should be noted that the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or server that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products or devices.

[0029] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0030] like Figure 1 and Figure 2 As shown, a lightweight normally open solenoid valve includes a valve housing 2, a valve seat 9, and a valve core assembly arranged between the valve housing 2 and the valve seat 9. The valve core assembly includes a static iron core 1 fixed to the inside of the valve housing 2, an electromagnetic coil 4 sleeved on the outside of the static iron core 1 via a coil skeleton 3, a movable iron core 5 arranged at the bottom of the static iron core 1, and a spring assembly. The valve housing 2 and the valve seat 9 are both made of a composite material composed of a polyetheretherketone matrix and a 3D woven carbon fiber reinforcement through molding, and the carbon fiber volume accounts for 25%-35%, and the material density is ≤1.5g / cm 3 , tensile strength ≥ 200MPa; the moving iron core 5 and the static iron core 1 are both hollow cylindrical structures.

[0031] A flow channel 10 is provided in the valve seat 9, a conical sealing head 8 is provided at the bottom end of the moving iron core 5 and at a position corresponding to the flow channel 10, a conical guide hole is provided on the flow channel 10 and at a position corresponding to the conical sealing head 8, a spiral guide groove is provided on the inner wall of the conical guide hole, and the depth of the spiral guide groove is 1mm-2mm.

[0032] The conical sealing head 8 is made of titanium alloy TC4, and is integrated with the moving iron core 5 by vacuum diffusion welding, and the shear strength of the welding interface is ≥300 MPa.

[0033] The contact angle between the conical sealing head 8 and the conical guide hole is 45°±1°, and the surface of the conical guide hole is covered with a tungsten carbide-cobalt alloy coating with a thickness of 0.2-0.4 mm by a plasma spraying process.

[0034] The winding of the electromagnetic coil 4 adopts Litz wire with a diameter of 0.1mm-0.15mm, with a turn density of ≥150 turns per square centimeter, and the coil skeleton 3 adopts a hollow structure design with a hollow ratio ≥35%.

[0035] The spring assembly is a two-stage spring structure, which includes a first spring 6 arranged between the moving iron core 5 and the valve housing 2 and a second spring 7 arranged between the coil skeleton 3 and the moving iron core 5, and the elastic coefficient of the first spring 6 is 4-6 times the elastic coefficient of the second spring 7.

[0036] The first spring 6 is made of Ti-6Al-4V, and the second spring 7 is made of 17-7PH stainless steel.

[0037] A nickel-phosphorus alloy layer with a thickness of 0.051 mm to 0.1 mm is deposited on the composite material outer surface of the valve housing 2 by a chemical plating process, and the surface roughness Ra is ≤ 0.8 μm.

[0038] Working process: Normally open state: Under normal conditions, the preload force of the first spring 6 and the second spring 7 pushes the moving iron core 5 away from the valve seat 9, a guide gap is left between the conical sealing head 8 and the conical guide hole, the flow channel 10 is in the open state, and the fluid passes through the flow channel 10.

[0039] Closing process: After the electromagnetic coil 4 is energized, the electromagnetic force generated overcomes the combined force of the first spring 6 and the second spring 7, driving the moving iron core 5 to move toward the valve seat 9 until the conical sealing head 8 is completely fitted with the conical guide hole and the flow channel 10 is closed.

[0040] Example

[0041] The composite material of the valve housing and valve seat is: polyetheretherketone (PEEK) matrix + 3D woven carbon fiber (30% by volume). The molding process parameters are: temperature 380-400℃, pressure 15-20MPa, and holding time 10-15min. Composite material performance: density 1.45g / cm 3 , a tensile strength of 220 MPa, a flexural modulus of 12 GPa, and a temperature resistance range of -60°C to 260°C. The valve housing surface treatment: an electroless nickel-phosphorus alloy plating layer with a thickness of 0.08 μm and a surface roughness of Ra = 0.6 μm. It showed no corrosion after a 1000-hour salt spray test. Experimental results show that the valve housing and seat weigh only 85g, a 72% reduction compared to traditional stainless steel components. It withstands a pressure test of 12 MPa with no deformation, meeting high-pressure operating requirements.

[0042] Structurally: the static iron core (fixed in the valve housing) and the moving iron core (connected to the conical sealing head) are both hollow cylinders, with a wall thickness of 1.5mm for the static iron core and 1.2mm for the moving iron core, resulting in an overall weight reduction of 40%.

[0043] The spiral guide groove on the conical guide hole has a depth of 1.5mm and a helix angle of 25°, and the flow coefficient is increased to 1.3 (the traditional structure is 0.9).

[0044] The two-stage spring structure achieves a valve opening time of 2.8ms and a valve closing time of 3.5ms (compared to ≥10ms for a traditional single-spring structure). Furthermore, the electromagnetic coil's starting current is 1.2A (lasting 10ms) and its holding current is 0.4A (steady-state power consumption 1.2W), saving 76% energy compared to traditional designs, thus verifying the effectiveness of the invention.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solutions of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A lightweight normally open solenoid valve, comprising a valve housing, a valve seat, and a valve core assembly disposed between the valve housing and the valve seat. The valve core assembly comprises a stationary iron core fixed to the interior of the valve housing, an electromagnetic coil sleeved around the exterior of the stationary iron core via a coil bobbin, a movable iron core disposed at the bottom of the stationary iron core, and a spring assembly. The valve core assembly is characterized by: The valve housing and valve seat are both made of a composite material consisting of a polyetheretherketone matrix and a 3D woven carbon fiber reinforcement through compression molding, with the carbon fiber volume accounting for 25%-35% and the material density ≤1.5g / cm 3 , tensile strength ≥ 200MPa; Both the moving iron core and the static iron core are hollow cylindrical structures.

2. A lightweight normally open solenoid valve according to claim 1, characterized in that: A flow channel is provided in the valve seat, a conical sealing head is provided at the bottom end of the moving iron core and corresponding to the flow channel, a conical guide hole is provided on the flow channel and corresponding to the conical sealing head, a spiral guide groove is provided on the inner wall of the conical guide hole, and the depth of the spiral guide groove is 1mm-2mm.

3. A lightweight normally open solenoid valve according to claim 2, characterized in that: The conical sealing head is made of titanium alloy TC4, which is integrated with the moving iron core through vacuum diffusion welding, and the shear strength of the welding interface is ≥300MPa.

4. A lightweight normally open solenoid valve according to claim 3, characterized in that: The contact angle between the conical sealing head and the conical guide hole is 45°±1°, and the surface of the conical guide hole is covered with a tungsten carbide-cobalt alloy coating with a thickness of 0.2-0.4 mm by a plasma spraying process.

5. A lightweight normally open solenoid valve according to claim 4, characterized in that: The winding of the electromagnetic coil adopts Litz wire with a diameter of 0.1mm-0.15mm, the turn density per square centimeter is ≥150 turns, and the coil skeleton adopts a hollow structure design with a hollow rate ≥35%.

6. A lightweight normally open solenoid valve according to claim 5, characterized in that: The spring assembly is a two-stage spring structure, which includes a first spring arranged between the moving iron core and the valve housing and a second spring arranged between the coil skeleton and the moving iron core, and the elastic coefficient of the first spring is 4-6 times the elastic coefficient of the second spring.

7. A lightweight normally open solenoid valve according to claim 6, characterized in that: The first spring is made of Ti-6Al-4V and the second spring is made of 17-7PH stainless steel.

8. The lightweight normally open solenoid valve according to claim 1, characterized in that: The composite material outer surface of the valve housing is deposited with a nickel-phosphorus alloy layer having a thickness of 0.051mm-0.1mm by a chemical plating process, and the surface roughness Ra is ≤ 0.8μm.

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