Injection valve heat insulation device and vehicle
By introducing a flow guide and cooling chamber structure into the injection valve, and utilizing the coolant to absorb and conduct high-temperature heat, the stability and cost issues of the injection valve in high-temperature environments are solved, thereby improving the reliability and cost-effectiveness of the injection valve.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- FAW JIEFANG AUTOMOTIVE CO
- Filing Date
- 2026-03-19
- Publication Date
- 2026-05-05
AI Technical Summary
In the prior art, the valve body of the injection valve undergoes secondary tempering in a high-temperature environment, which leads to a decrease in stability and sealing reliability. Furthermore, using high-temperature alloy materials with better heat resistance is costly and complex to process.
The jet valve heat insulation device includes a valve body and a guide shield. A cooling cavity is formed between the guide shield and the valve body. The coolant absorbs high-temperature heat and conducts it to the outside of the valve body through the cooling oil passage, which avoids high-temperature backfire and reduces costs.
It effectively blocks or diverts the conduction of high combustion temperatures, improves the stability and sealing reliability of the injection valve, reduces costs, and ensures injection performance and vehicle power and stability.
Smart Images
Figure CN121976901A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of vehicle technology, and more particularly to a jet valve heat insulation device and a vehicle. Background Technology
[0002] As a core precision component of the internal combustion engine's fuel supply system, the fuel injection valve's performance directly affects the engine's combustion efficiency, power output, and emissions levels. An injection valve typically includes a valve body, a needle valve assembly housed within the valve body, and a drive mechanism. The needle valve body is the key moving component that withstands high-pressure fuel and achieves high-frequency opening and closing to complete precise injection. During engine operation, especially in direct injection engines, the nozzle portion of the injection valve is directly exposed to or very close to the high-temperature, high-pressure combustion chamber environment. This means the needle valve body not only bears mechanical loads but also continuously withstands the high-temperature thermal loads from the combustion chamber.
[0003] In the existing technology, the high temperature generated by fuel combustion in the combustion chamber is directly conducted inward through the valve body wall of the injection valve. When the temperature of the area where the needle valve body is located exceeds the tempering temperature of its material heat treatment for a long time, the material of the needle valve body will undergo secondary tempering. The continuous softening and aging of the material at high temperature seriously affects the stability and sealing reliability of the injection valve.
[0004] To address these issues, high-temperature alloys and other materials with superior heat resistance are used for the needle valve body. However, these materials are extremely expensive and their processing is complex, leading to a significant increase in the overall manufacturing cost of the injection valve. Therefore, effectively blocking or diverting the transmission of high combustion temperatures to the valve body without significantly increasing material costs or changing the materials themselves has become a critical technical challenge for improving the reliability and reducing the cost of injection valves. Summary of the Invention
[0005] The purpose of this invention is to provide a heat insulation device for an injection valve and a vehicle to solve the aforementioned problems of injection valves in the related art.
[0006] To address the aforementioned problems in the existing technology, the present invention adopts the following technical solution:
[0007] The jet valve heat insulation device includes:
[0008] The valve body has a first end and a second end, the first end having a cooling oil passage and the second end having a mating sealing surface.
[0009] A flow guide is fitted onto the valve body. The flow guide has a first opening and a second opening. The first opening is sealed to the valve body. The flow guide has a sealing cone surface located at the second opening and sealed to the mating sealing surface. Along the circumferential direction of the flow guide, there is a cooling cavity between the flow guide and the valve body for containing coolant. The cooling cavity is connected to the cooling oil passage.
[0010] As an optional technical solution, the jet valve heat insulation device further includes a sealing element. The flow guide is provided with a sealing groove, which is located at the first opening. The sealing element is disposed in the sealing groove and is sealed to the valve body.
[0011] As an optional technical solution, the jet valve heat insulation device further includes a heat exchanger, which is connected to the cooling oil passage and is used to exchange heat with the cooling cavity.
[0012] As an optional technical solution, the injection valve heat insulation device further includes a thermostat, which is disposed in the cooling oil passage. The thermostat is used to detect the oil temperature of the cooling chamber. When the oil temperature of the cooling chamber is lower than a set value, the thermostat closes the cooling oil passage. When the oil temperature of the cooling chamber is higher than the set value, the thermostat opens the cooling oil passage.
[0013] As an optional technical solution, the outer periphery of the valve body is provided with external threads, the inner ring of the first opening is provided with internal threads, and the valve body is threadedly connected to the flow guide cover.
[0014] As an optional technical solution, the angle between the sealing cone surface and the horizontal plane is 60°, the horizontal plane is parallel to the first direction, and the angle between the mating sealing surface and the horizontal plane is 60°.
[0015] As an optional technical solution, the jet valve heat insulation device further includes a heat insulation layer, which is disposed on the outer periphery of the flow guide shroud.
[0016] As an optional technical solution, the heat insulation layer is made of high-temperature resistant material.
[0017] As an optional technical solution, the thickness of the insulation layer ranges from 0.5 to 2.5 mm.
[0018] To achieve the above objectives, the present invention also provides a vehicle, including an engine and the above-mentioned injection valve heat insulation device, wherein the injection valve heat insulation device is installed on the engine.
[0019] The jet valve heat insulation device and vehicle provided by the present invention have at least the following beneficial effects:
[0020] The heat insulation device for the injection valve includes a valve body and a guide shield. The valve body has a first end and a second end. The first end has a cooling oil passage, and the second end has a mating sealing surface. The guide shield is fitted onto the valve body and has a first opening and a second opening. The first opening is sealed to the valve body, and the guide shield has a sealing cone surface located at the second opening, which is sealed to the mating sealing surface. Along the circumference of the guide shield, there is a cooling chamber between the guide shield and the valve body for containing coolant. The cooling chamber is connected to the cooling oil passage. When the engine combustion chamber generates high temperatures, the coolant in the cooling chamber absorbs the high-temperature heat from outside the guide shield. Then, the coolant conducts the heat to the valve body through the cooling oil passage, effectively preventing high-temperature backfire from being conducted to the valve body and reducing its structural strength, thus improving the stability of the valve body's operation. This ensures the injection effect of the injection valve, and the valve body does not need to use new materials to cope with the high-temperature combustion environment, reducing costs.
[0021] The vehicle includes an engine and a heat insulation device for the injection valve, with the heat insulation device mounted on the engine. The fairing has a sealing cone surface, and the second end of the valve body has a mating sealing surface. The sealing cone surface and the mating sealing surface are sealed together. The first opening of the fairing is sealed to the valve body. Furthermore, along the circumference of the fairing, there is a cooling chamber between the fairing and the valve body for containing coolant. During combustion, the engine combustion chamber continuously generates high-temperature heat. The coolant in the cooling chamber absorbs the high-temperature heat from outside the fairing. Then, the coolant conducts the heat to the valve body through cooling oil passages, preventing direct heat transfer to the valve body and thus avoiding impact on its structural strength. This ensures the injection effect of the injection valve, thereby guaranteeing the vehicle's power and stability. Attached Figure Description
[0022] Figure 1 This is a schematic diagram of the structure of the jet valve heat insulation device in an embodiment of the present invention;
[0023] Figure 2 This is a schematic diagram of the structure of the flow guide in an embodiment of the present invention.
[0024] In the picture:
[0025] 1. Valve body; 11. Cooling oil passage; 12. Mating sealing surface;
[0026] 2. Shielding; 21. Sealing cone surface; 22. Sealing groove;
[0027] 3. Cooling chamber;
[0028] 4. Sealing components;
[0029] 5. Insulation layer. Detailed Implementation
[0030] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0031] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions. Furthermore, "above," "on top of," and "over" the first feature in relation to the second feature includes the first feature directly above and diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "under," and "below" the first feature in relation to the second feature includes the first feature directly below and diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0032] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0033] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.
[0034] like Figures 1 to 2As shown, this embodiment provides a heat insulation device for an injection valve, which includes a valve body 1 and a flow guide 2. The valve body 1 has a first end and a second end. The first end has a cooling oil passage 11, and the second end has a mating sealing surface 12. The flow guide 2 is fitted onto the valve body 1 and has a first opening and a second opening. The first opening is sealed to the valve body 1. The flow guide 2 has a sealing cone surface 21 located at the second opening and sealed to the mating sealing surface 12. Along the circumferential direction of the flow guide 2, a cooling chamber 3 for containing coolant is provided between the flow guide 2 and the valve body 1. The cooling chamber 3 is connected to the cooling oil passage 11.
[0035] For example, a needle valve is elastically provided inside the valve body 1 by a spring. Under the action of the spring, the needle valve can slide relative to the valve body 1 to open or close the oil injection hole of the valve body 1 to inject oil.
[0036] Along the circumferential direction of the valve body 1, a flow guide 2 is fixedly fitted onto the outer circumference of the valve body 1. The first opening of the flow guide 2 is sealed to the first end of the valve body 1. The second opening of the flow guide 2 is provided with a sealing cone surface 21. A mating sealing surface 12 is provided at the second end of the valve body 1, and the cone angle of the mating sealing surface 12 matches that of the sealing cone surface 21, ensuring a tight seal and forming a sealing ring. A cooling chamber 3 is formed between the flow guide 2 and the valve body 1. Along the axial direction of the valve body 1, the cooling chamber 3 is located between the sealing ring and the first opening, forming a relatively sealed cavity. The cooling chamber 3 contains a coolant, specifically cooling oil, used to cool the heat of the valve body 1. A cooling oil passage 11 is provided at the first end of the valve body 1. The coolant in the cooling chamber 3 can only be transferred through the cooling oil passage 11, and the equivalent diameter of the cooling chamber 3 is at least twice the diameter of the cooling oil passage 11. When the combustion chamber of the engine generates high temperature, the coolant in the cooling cavity 3 will absorb the high temperature heat generated by combustion and transport it to the outside of the valve body 1 through the cooling oil passage 11. This effectively prevents the high temperature backfire from being conducted to the valve body 1 and reducing its structural strength, thereby improving the working stability of the valve body 1. The valve body 1 of the injection valve does not need to use new materials to cope with the high temperature environment of combustion, thus reducing costs.
[0037] The working process of the injection valve heat insulation device is as follows: During the combustion process, the engine combustion chamber will continuously generate high temperature heat. The coolant in the cooling chamber 3 absorbs the high temperature heat outside the guide shroud 2. Then, the coolant conducts the heat to the outside of the valve body 1 through the cooling oil passage 11, avoiding the high temperature heat from being directly conducted to the valve body 1 and affecting the structural strength of the valve body 1, thereby ensuring the injection effect of the injection valve.
[0038] Furthermore, referring to Figures 1-2The jet valve heat insulation device also includes a sealing element 4. The flow guide shroud 2 has a sealing groove 22, which is located at the first opening. The sealing element 4 is disposed in the sealing groove 22 and is sealed to the valve body 1.
[0039] The sealing element 4 is a sealing ring made of rubber. The inner wall of the first opening of the flow guide 2 is provided with a sealing groove 22, which has an annular structure. The flow guide 2 is fixedly sleeved on the outer periphery of the valve body 1. The inner side of the first opening of the flow guide 2 is sealed to the outer periphery of the first end of the valve body 1 through the sealing element 4. The sealing element 4 is set in the sealing groove 22 and abuts against the first end of the valve body 1. Under the action of the sealing element 4, the first end of the valve body 1 and the first opening of the flow guide 2 are sealed together, ensuring the sealing of the cooling chamber 3. The coolant in the cooling chamber 3 can only be transported through the cooling oil passage 11, avoiding the leakage of coolant in the cooling chamber 3 and affecting the normal operation of the injection valve.
[0040] Optionally, the sealing groove 22 is a stepped groove with a rectangular longitudinal section, and the bottom width of the sealing groove 22 is greater than the opening width. Correspondingly, the sealing element 4 is a shaped sealing ring with matching dimensions. After being installed in the stepped sealing groove 22, the sealing ring has a larger contact area and better resistance to extrusion deformation. In particular, the sidewall of the sealing groove 22 can be set as a guide slope to facilitate the installation of the sealing element 4. When the sealing element 4 is under pressure, its upper and lower sealing lips tightly fit the outer surface of the valve body 1 and the bottom of the sealing groove 22, respectively, realizing a combination of bidirectional axial sealing and radial sealing. For the injection valve, which has slight axial movement, it has better sealing adaptability and a longer service life.
[0041] Furthermore, referring to Figures 1-2 The jet valve heat insulation device also includes a heat exchanger and a thermostat. The heat exchanger is connected to the cooling oil passage 11 and is used for heat exchange with the cooling chamber 3. The thermostat is located in the cooling oil passage 11 and is used to detect the oil temperature of the cooling chamber 3. When the oil temperature of the cooling chamber 3 is lower than the set value, the thermostat closes the cooling oil passage 11; when the oil temperature of the cooling chamber 3 is higher than the set value, the thermostat opens the cooling oil passage 11.
[0042] The heat exchanger is located outside the flow guide shroud 2. The input end of the heat exchanger is connected to the cooling oil passage 11. The flow guide shroud 2 also has a return oil passage connected to the cooling chamber 3, which in turn connects to the output end of the heat exchanger. Considering the actual temperature requirements of the injection valve, when the thermostat detects that the coolant oil temperature in the cooling chamber 3 is below 85°C, the thermostat is closed, meaning the cooling oil passage 11 is disconnected, and the coolant in the cooling chamber 3 remains in a natural cooling state, unable to enter or exit through the cooling oil passage 11 or the return oil passage. When the thermostat detects that the coolant oil temperature in the cooling chamber 3 is above 85°C, the thermostat is open, and the coolant in the cooling chamber 3 enters the heat exchanger through the cooling oil passage 11. The heat exchanger cools and lowers the high-temperature heat carried out by the coolant and returns it to the cooling chamber 3 through the return oil passage, thus ensuring that the cooling chamber 3 is in a state of circulating cooling.
[0043] Furthermore, referring to Figures 1-2 The outer circumference of the valve body 1 is provided with external threads, and the inner ring of the first opening is provided with internal threads. The valve body 1 is threadedly connected to the flow guide shroud 2.
[0044] The outer peripheral wall of the first end of the valve body 1 is machined with an external thread, and the inner ring corresponding to the first opening of the flow guide shroud 2 is machined with an internal thread. The threaded engagement between the external and internal threads allows for a detachable connection between the flow guide shroud 2 and the valve body 1. Furthermore, by screwing the flow guide sleeve along the axial direction of the valve body 1, the lower end face of the valve body 1 can press against the seal 4 on the flow guide shroud 2 and the upper end face where the seal 4 is located, ensuring that the compression of the seal 4 is within the normal range. Under the action of the seal 4, a sealing connection is achieved between the surfaces of the valve body 1 and the flow guide shroud 2, ensuring the sealing of the coolant within the cooling chamber 3.
[0045] During assembly, the seal 4 is first placed into the sealing groove 22 of the air guide 2. Then, the air guide 2 is aligned with the valve body 1 and screwed on. At this time, the seal 4 is compressed between the valve body 1 and the sealing groove 22 to form a seal. After the cooling oil circuit is connected to the cooling chamber 3, a complete cooling circuit is formed. The threaded connection provides uniform locking force in both the circumferential and axial directions, which can resist the vibration and impact during engine operation, prevent the air guide 2 from loosening, and ensure the stability of the cooling chamber 3 structure.
[0046] The injection valve operates under high temperature and vibration conditions for extended periods. The external thread profile is specially designed, employing a thread profile with a 30° wedge-shaped bevel. When the flow guide shroud 2 is tightened onto the valve body 1, the wedge-shaped surfaces of the threads mesh, generating a normal force far greater than that of ordinary threads. Its radial component forms a powerful anti-loosening friction force. Optionally, a deformed thread section or thread-locking adhesive can be applied to the end of the internal thread. When tightened to this position, additional resistance torque is generated, achieving mechanical or chemical anti-loosening. Optionally, after the flow guide shroud 2 is tightened in place, a radial locking pin hole can be drilled at the joint between the valve body 1 and the flow guide shroud 2, and a locking pin can be driven in. This locking pin passes through the wall thickness of both the valve body 1 and the flow guide shroud 2, preventing the possibility of relative rotation between them, suitable for applications requiring extremely high reliability of the injection valve.
[0047] Furthermore, referring to Figures 1-2 The sealing cone surface 21 has an angle of 60° with the horizontal plane, the horizontal plane is set parallel to the first direction, and the mating sealing surface 12 has an angle of 60° with the horizontal plane.
[0048] The first direction is direction AB in the diagram. Using the horizontal plane of the first direction as a reference, the inner side of the second opening of the flow guide 2 is set at a conical angle; that is, the angle between the sealing cone surface 21 of the flow guide 2 and the horizontal plane is the outer cone angle, which is 60 degrees. The outer periphery of the second end of the valve body 1 is set at a conical angle; that is, the angle between the mating sealing surface 12 of the valve body 1 and the horizontal plane is the inner cone angle, which is 60 degrees. The angle difference between the inner and outer cone angles is 1 to 2 degrees. The cone angles of the mating sealing surface 12 and the sealing cone surface 21 match, allowing the sealing cone surface 21 and the mating sealing surface 12 to seal and fit together to form a sealing ring. A torque force of 50 Nm acts on the flow guide 2, forming a relatively sealed cooling chamber 3 between the valve body 1 and the flow guide 2.
[0049] Furthermore, referring to Figures 1-2 The jet valve heat insulation device also includes a heat insulation layer 5, which is disposed on the outer periphery of the flow guide shroud 2.
[0050] The heat insulation layer 5 is made of a high-temperature resistant material, and its thickness ranges from 0.5 to 2.5 mm. In this embodiment, the outer layer of the flow guide 2 is coated with the heat insulation layer 5, which has a thickness of 1 mm. The material of the heat insulation layer 5 is niobium carbide, which has a melting point between 2300°C and 3500°C. It has an extremely high melting point and excellent high-temperature stability, and can isolate most of the high-temperature heat outside the flow guide 2. The remaining high-temperature heat is conducted through the heat insulation layer 5 to the cooling cavity 3 for absorption by the coolant. Optionally, the material of the heat insulation layer 5 includes, but is not limited to, composite heat insulation materials composed of ceramic matrix composites, aerogel felt, high-performance heat insulation coatings, or multilayer metal reflective foils.
[0051] Considering the temperature gradient along the axial direction of the fairing 2, the thickness of the heat insulation layer 5 can vary along the axial direction. The temperature is highest at the lower part of the fairing 2 near the combustion chamber, corresponding to a thicker heat insulation layer 5 or the use of a material with superior heat insulation performance. Conversely, the temperature is lowest at the upper part of the fairing 2 near the combustion chamber, allowing for a thinner heat insulation layer 5. This achieves optimized distribution of the heat insulation performance of the heat insulation layer 5, ensuring the best heat insulation effect while controlling overall weight and cost.
[0052] This embodiment also provides a vehicle, including an engine and the injection valve heat insulation device described above, which is installed on the engine. The deflector 2 is provided with a sealing cone surface 21, and the second end of the valve body 1 is provided with a mating sealing surface 12. The sealing cone surface 21 and the mating sealing surface 12 are sealed together. The first opening of the deflector 2 is sealed together with the valve body 1. Furthermore, along the circumferential direction of the deflector 2, a cooling chamber 3 for containing coolant is provided between the deflector 2 and the valve body 1. During combustion, the engine combustion chamber continuously generates high-temperature heat. The coolant in the cooling chamber 3 absorbs the high-temperature heat from outside the deflector 2. Then, the coolant conducts the heat to the outside of the valve body 1 through the cooling oil passage 11, preventing the high-temperature heat from being directly conducted to the valve body 1 and affecting its structural strength, thus ensuring the injection effect of the injection valve and guaranteeing the vehicle's power and stability.
[0053] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.
Claims
1. A heat insulation device for a jet valve, characterized in that, include: The valve body (1) has a first end and a second end. The first end is provided with a cooling oil passage (11), and the second end is provided with a mating sealing surface (12). A flow guide (2) is fitted onto the valve body (1). The flow guide (2) has a first opening and a second opening. The first opening is sealed to the valve body (1). The flow guide (2) is provided with a sealing cone surface (21). The sealing cone surface (21) is located at the second opening and is sealed to the mating sealing surface (12). Along the circumferential direction of the flow guide (2), there is a cooling chamber (3) between the flow guide (2) and the valve body (1) for containing coolant. The cooling chamber (3) is connected to the cooling oil passage (11).
2. The jet valve heat insulation device according to claim 1, characterized in that, The jet valve heat insulation device also includes a sealing element (4), the flow guide (2) has a sealing groove (22), the sealing groove (22) is located at the first opening, the sealing element (4) is disposed in the sealing groove (22), and the sealing element (4) is sealed to the valve body (1).
3. The jet valve heat insulation device according to claim 1, characterized in that, The jet valve heat insulation device also includes a heat exchanger, which is connected to the cooling oil passage (11) and is used to exchange heat with the cooling cavity (3).
4. The jet valve heat insulation device according to claim 1, characterized in that, The jet valve heat insulation device also includes a thermostat, which is located in the cooling oil passage (11). The thermostat is used to detect the oil temperature of the cooling chamber (3). When the oil temperature of the cooling chamber (3) is lower than the set value, the thermostat closes the cooling oil passage (11). When the oil temperature of the cooling chamber (3) is higher than the set value, the thermostat opens the cooling oil passage (11).
5. The jet valve heat insulation device according to claim 1, characterized in that, The valve body (1) has an external thread on its outer periphery and an internal thread on the inner ring of the first opening. The valve body (1) is threadedly connected to the flow guide (2).
6. The jet valve heat insulation device according to claim 1, characterized in that, The angle between the sealing cone surface (21) and the horizontal plane is 60°, the horizontal plane is parallel to the first direction, and the angle between the mating sealing surface (12) and the horizontal plane is 60°.
7. The jet valve heat insulation device according to claim 1, characterized in that, The jet valve heat insulation device also includes a heat insulation layer (5), which is disposed on the outer periphery of the flow guide (2).
8. The jet valve heat insulation device according to claim 7, characterized in that, The heat insulation layer (5) is made of high-temperature resistant material.
9. The jet valve heat insulation device according to claim 7, characterized in that, The thickness of the insulation layer (5) ranges from 0.5 to 2.5 mm.
10. A vehicle, characterized in that, The invention includes an engine and the injection valve heat insulation device as described in any one of claims 1-9, wherein the injection valve heat insulation device is installed in the engine.