High-capacity pressure storage cavity type oil sprayer

Abstract

The invention belongs to the technical field of oil sprayers, and discloses a large-capacity pressure storage cavity type oil sprayer which comprises an oil inlet block, a device body and a flow limiting valve assembly, the oil inlet block and the device body are coaxially arranged and connected with each other, the oil inlet block is provided with multiple oil inlets and high-pressure oil inlet channels, the high-pressure oil inlet channels are arranged in the axial direction of the oil inlet block, and the multiple oil inlets are arranged in the circumferential direction of the oil inlet block; any oil inlet extends in the radial direction of the oil inlet block and communicates with the high-pressure oil inlet channel. The device body is provided with a pressure storage cavity in the axial direction of the device body, the high-pressure oil inlet channel communicates with the pressure storage cavity, the flow limiting valve assembly is arranged at the communicating position of the high-pressure oil inlet channel and the pressure storage cavity, and the flow limiting valve assembly is used for making the high-pressure oil inlet channel communicate with the pressure storage cavity or blocking communication of the high-pressure oil inlet channel and the pressure storage cavity. The invention relates to a large-capacity pressure storage cavity type oil injector which integrates the functions of a common rail pipe and a flow-limiting valve, has the advantages of being compact in structure and small in occupied space, can be conveniently applied to a space-limited environment, and meanwhile can achieve high-power output and meet the requirements of emission regulations.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of fuel injectors, and particularly relates to a large-volume pressure accumulation chamber type fuel injector. BACKGROUND

[0002] In a conventional common rail fuel system, a large-volume common rail pipe is usually configured as a core component for storing high-pressure fuel and realizing uniform distribution of the fuel. A flow limiting valve assembly is often independently installed on the common rail pipe for adjusting the flow state of the fuel. This design leads to a complex overall structure of the system, involves multiple key installation positions, requires high assembly precision, and significantly increases the difficulty of guaranteeing operation reliability.

[0003] Due to the large volume of the common rail pipe, the entire system occupies a large space, making the space arrangement requirement extremely prominent. In a space-limited application environment, such as some internal combustion engine vehicles, small ship power devices or compact power generation equipment, it is difficult to accommodate such a large common rail fuel system. If the large common rail system is abandoned, the physical size of the diesel engine will be restricted by the limited space, resulting in the inability to achieve high-power output and difficulty in meeting the strict requirements of modern emission regulations for pollution control. The contradiction between space efficiency and performance demand is increasingly prominent, and the existing technology is difficult to balance high-power output and emission compliance in a limited space, and a compact and functionally integrated solution is urgently needed.

[0004] In view of the above problems, the existing technology needs to be improved. SUMMARY

[0005] The present application aims to provide a large-volume pressure accumulation chamber type fuel injector, which integrates the functions of the common rail pipe and the flow limiting valve, has the advantages of compact structure and small space occupation, is convenient to apply in a space-limited environment, and can realize high-power output and meet the requirements of emission regulations.

[0006] In order to achieve the above-mentioned purpose, the technical scheme of the present application is as follows: a large-volume pressure accumulation chamber type fuel injector, comprising an oil inlet block, a body and a flow limiting valve assembly, the oil inlet block and the body are coaxially arranged and connected to each other, the oil inlet block is provided with an oil inlet port and a high-pressure oil inlet channel, the high-pressure oil inlet channel is arranged along the axial direction of the oil inlet block, the oil inlet port is arranged in multiple along the circumferential direction of the oil inlet block, and any oil inlet port extends along the radial direction of the oil inlet block and communicates with the high-pressure oil inlet channel; the body is provided with a pressure accumulation chamber along the axial direction of the body, the high-pressure oil inlet channel communicates with the pressure accumulation chamber, the flow limiting valve assembly is arranged at the communication position of the high-pressure oil inlet channel and the pressure accumulation chamber, and the flow limiting valve assembly is used to make the high-pressure oil inlet channel communicate with the pressure accumulation chamber or block the communication of the high-pressure oil inlet channel and the pressure accumulation chamber.

[0007] Further, the flow limiting valve assembly comprises a valve body and a cut-off steel ball arranged in the valve body, the front end of the valve body is inserted into the oil inlet block, the rear end of the valve body is inserted into the device body, the valve body is provided with a through inner channel along the central axis of the valve body, the high-pressure oil inlet channel and the pressure accumulation cavity are communicated through the inner channel; the front part of the inner channel is a volume cavity, the volume cavity is provided with a cut-off part, the cut-off part is a horn-shaped structure with a gradually decreasing radial size from front to back, the cut-off steel ball is arranged in the volume cavity and located in front of the cut-off part, the cut-off steel ball divides the volume cavity into volume cavity A and volume cavity B; the cut-off steel ball can be driven to move axially and abut against the cut-off part to cut off the inner channel, and the cut-off steel ball can also be driven to move axially and away from the cut-off part to communicate the high-pressure oil inlet channel and the pressure accumulation cavity.

[0008] Further, the flow limiting valve assembly further comprises a flow limiting valve spring, the flow limiting valve spring is installed in the volume cavity and located behind the cut-off steel ball, the flow limiting valve spring is in a pre-pressed state in the installed state, and the cut-off steel ball has a tendency to move away from the cut-off part under the elastic force of the flow limiting valve spring.

[0009] Further, the flow limiting valve assembly further comprises a filter element, the rear part of the inner channel is a filter cavity, and the filter element is installed in the filter cavity of the inner channel.

[0010] Further, the radial size of the end of the inner channel is reduced to form a throttling hole, and the filter cavity and the throttling hole are transitionally connected through a horn mouth structure.

[0011] Further, the high-pressure oil inlet channel is composed of a plurality of parallel oil inlet branches.

[0012] Further, the locking connection sleeve is provided, and the two ends of the locking connection sleeve are respectively sleeved with the rear end of the oil inlet block and the front end of the device body, so that the oil inlet block and the device body form a detachable connection.

[0013] Further, the high-pressure seal I and the high-pressure seal II are further provided, the high-pressure seal I is arranged at the position of the contact surface between the rear end face of the oil inlet block and the valve body, and the high-pressure seal II is arranged at the position of the contact surface between the rear end face of the valve body and the device body.

[0014] Further, the inner part of the oil inlet block is provided with a leakage oil channel, the gaps among the oil inlet block, the valve body, the device body and the locking connection sleeve form a leakage oil cavity, and the leakage oil cavity is communicated with the oil inlet through the leakage oil channel.

[0015] Further, the flow limiting valve assembly further comprises an adjusting gasket, the adjusting gasket is installed at the end of the volume cavity, one end of the flow limiting valve spring abuts against the adjusting gasket, and the other end abuts against the cut-off steel ball.

[0016] The beneficial effects of the technical scheme are as follows:

[0017] This invention relates to a large-capacity accumulator injector. By incorporating an accumulator chamber within the injector body, and in conjunction with an inlet block having multiple inlets, multiple injectors can be used in series to replace the traditional common rail. This reduces the number of high-pressure interfaces in the fuel system, improves reliability, and makes it possible to install a high-power common rail fuel system within a limited space. Simultaneously, an independent flow-limiting valve assembly is integrated within the injector, ensuring stable injector operation while preventing the injector from occupying the accumulator chamber volume. This further ensures that the accumulator chamber volume meets requirements, thus replacing the common rail. Compared to existing technologies, the injector of this invention, through its integrated design, reduces space occupation, has a compact structure, is easy to apply in space-constrained environments, and simultaneously achieves high power output while meeting emission regulations. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a large-capacity accumulator injector according to the present invention. Detailed Implementation

[0019] The following detailed description illustrates the specific implementation method:

[0020] The reference numerals in the accompanying drawings include: oil inlet block 1, high-pressure oil inlet channel 2, leakage oil channel 3, volume chamber A4, cut-off steel ball 5, volume chamber B6, flow limiting valve spring 7, adjusting shim 8, filter element 9, locking connecting sleeve 10, valve body 11, accumulator chamber 12, device body 13, throttling orifice 14, high-pressure seal I 15, and high-pressure seal II 16.

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. 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. In this embodiment, the terms "before," "after," "first," and "last" are all determined based on the direction of medium flow, that is, along the axial direction, the fluid that flows first is "before" or "first," and vice versa; this is understandable to those skilled in the art and will not be elaborated here.

[0022] The basic implementation examples are as follows: Figure 1As shown: A large-capacity accumulator injector includes an inlet block 1, a body 13, and a flow restrictor assembly. The inlet block 1 and the body 13 are coaxially arranged and connected to each other. The inlet block 1 is provided with an inlet port and a high-pressure inlet channel 2. The high-pressure inlet channel 2 is arranged along the axial direction of the inlet block 1. Multiple inlets are arranged along the circumference of the inlet block 1, and each inlet extends radially along the inlet block 1 and communicates with the high-pressure inlet channel 2. The body 13 is provided with an accumulator 12 along its own axial direction. The high-pressure inlet channel 2 is connected to the accumulator 12. The flow restrictor assembly is arranged at the communication position between the high-pressure inlet channel 2 and the accumulator 12. The flow restrictor assembly is used to connect the high-pressure inlet channel 2 and the accumulator 12 or to block the communication between the high-pressure inlet channel 2 and the accumulator 12. Specifically, the fuel inlet block 1 is a component in the injector used to receive external high-pressure fuel and guide it into the internal flow channel. It is usually connected to the external fuel supply system and serves as a structural support for the front end of the injector. In this embodiment, the fuel inlet block 1 is provided with multiple fuel inlets for connecting to external high-pressure fuel lines. In this embodiment, two radially symmetrical inlets are preferred to ensure that multiple injectors can be connected in series to form a common fuel passage for injectors. The body 13 is the main structure in the injector used to support the accumulator chamber 12 and other internal components. The body 13 is connected to the fuel inlet block 1 and together they form the main support structure of the injector. The accumulator chamber 12 is the core volume inside the injector used to store high-pressure fuel. It can be machined into a cylindrical, conical, or irregularly shaped chamber as the accumulator chamber 12, with its axis aligned with the central axis of the body 13 to optimize fuel storage and pressure stability. The flow restrictor assembly controls the opening and closing of the oil circuit based on the pressure difference across the assembly, ensuring stable system operation. Under normal conditions, the pressure in the accumulator chamber 12 is the same as the inlet pressure of the high-pressure inlet channel 2, and the flow restrictor assembly is normally open, allowing normal fuel flow. When the injector malfunctions and injects too much fuel, the accumulator chamber 12 fails to replenish fuel in time, causing a pressure drop. At this time, the pressure in the high-pressure inlet channel 2 is higher than the pressure in the accumulator chamber 12, and the flow restrictor assembly closes under the pressure difference, cutting off the fuel flow path. It reopens after normal operation is restored. The flow restrictor assembly can be a simple valve core structure, controlled by an external drive mechanism to move the valve core axially or radially under a set pressure condition, thereby opening or closing the flow path. Alternatively, the flow restrictor assembly can be a one-way valve structure driven by an elastic element, automatically opening and closing the flow path under specific pressure conditions. The entire flow restrictor assembly can be installed inside the connection between the inlet block 1 and the body 13, spanning the boundary area between the high-pressure inlet channel 2 and the accumulator chamber 12, or integrated inside one of the components. Thus, this technical solution integrates the oil inlet block 1, the device body 13, and the flow restrictor valve assembly, and internally sets up an independent accumulator chamber 12 and a high-pressure oil inlet channel 2, effectively avoiding the dependence of traditional common rail fuel systems on independent common rail pipes and external flow restrictors.This injector significantly reduces the overall system's space footprint, enabling high-power output and meeting stringent emission requirements in space-constrained applications such as internal combustion locomotives.

[0023] In this embodiment, the flow limiting valve assembly includes a valve body 11 and a cutting-off steel ball 5 disposed within the valve body 11. The front end of the valve body 11 is inserted into the oil inlet block 1, and the rear end of the valve body 11 is inserted into the device body 13. The valve body 11 has a through-passage inner channel along its central axis. The high-pressure oil inlet channel 2 and the accumulator chamber 12 are connected through the inner channel. The front part of the inner channel is a volume chamber, and the volume chamber is provided with a flow-blocking part. The flow-blocking part is a trumpet-shaped structure with radial dimensions gradually decreasing from front to back. The cutting-off steel ball 5 is disposed in the volume chamber and located in front of the flow-blocking part. The cutting-off steel ball 5 divides the volume chamber into volume chamber A4 and volume chamber B6. The cutting-off steel ball 5 can be driven to move axially and abut against the flow-blocking part to cut off the inner channel. The cutting-off steel ball 5 can also be driven to move axially away from the flow-blocking part so that the high-pressure oil inlet channel 2 is connected to the accumulator chamber 12. Specifically, this embodiment introduces a valve structure by combining the valve body 11 and the cutting-off steel ball 5. Oil flow through the gap between the cutting-off steel ball 5 and the cavity wall replaces the traditional valve core oil flow. The pressure balance between cavity A4 and cavity B6 changes to close the flow-limiting valve, thereby cutting off the oil supply flow-limiting valve assembly and controlling the flow of high-pressure fluid. The through-flow channel along the central axis of the valve body 11 is the only path for high-pressure fluid to flow from the high-pressure inlet 2 to the accumulator 12. This internal channel design ensures directional fluid flow and provides space for the movement of the cutting-off steel ball 5, thus achieving effective control of the fluid path. In this embodiment, the inner channel is a stepped, continuous multi-chamber structure composed of multiple cavities with progressively decreasing diameters. The front part is a volume chamber, which itself is composed of two chambers. The volume chamber is provided with a flow-blocking section, which connects the two chambers to form a complete volume chamber. The cutting steel ball 5 is located in the front chamber of the volume chamber, that is, in front of the flow-blocking section. The flow-blocking section is a trumpet-shaped structure with radial dimensions gradually decreasing from front to back. This conical or trumpet-shaped design provides a precise sealing surface for the cutting steel ball 5. When the cutting steel ball 5 cooperates with the flow-blocking section, a reliable line contact or surface contact seal can be formed, effectively blocking the fluid passage. Meanwhile, after installation, the cutting-off steel ball 5 naturally divides the entire volume chamber into dynamically existing volume chambers A4 and B6. That is, as the steel ball 5 moves, the volumes of volume chambers A4 and B6 also change accordingly. The pressure value corresponding to volume chamber A4 represents the inlet pressure of the high-pressure oil inlet channel 2, and the pressure value corresponding to volume chamber B6 represents the pressure of the accumulator chamber 12. The cutting-off steel ball 5 moves according to the pressure difference between volume chambers A4 and B6 to connect or cut off the flow of the medium.The driving force for the cutting-off steel ball 5 can be internal, external, or both. Driven by either external or internal force, the cutting-off steel ball 5 moves axially along the valve body 11. When driven and pressed against the trumpet-shaped throttling part, a tight fit is formed between the steel ball 5 and the throttling part, effectively cutting off the inner channel and preventing high-pressure fluid from flowing from the high-pressure inlet channel 2 to the accumulator chamber 12. This pressing method utilizes the hardness of the steel ball 5 and the conical surface of the throttling part to achieve a reliable seal. When it is necessary to connect the high-pressure inlet channel 2 and the accumulator chamber 12, the cutting-off steel ball 5 is driven axially to disengage from the throttling part. Once the steel ball 5 is away from the throttling part, the inner channel is opened, allowing high-pressure fluid to freely pass through the inner channel and enter the accumulator chamber 12 from the high-pressure inlet channel 2. This movement ensures rapid opening of the fluid passage. As a preferred embodiment, after installation, the end of the inlet block 1 is also inserted into the front end of the body 13, thus forming a multi-layer nested structure to improve the overall sealing performance of the injector. Thus, the flow-limiting valve assembly, consisting of a valve body 11 and a cutting-off steel ball 5, forms a compact and functionally defined valve. Under the action of high-pressure fluid or external drive, the cutting-off steel ball 5 can move precisely axially and fit tightly with the trumpet-shaped throttling section. When the cutting-off steel ball 5 is pressed against the throttling section, its spherical surface forms a reliable line contact seal with the conical throttling section, effectively blocking the high-pressure fluid passage and preventing high-pressure oil from entering the accumulator chamber 12 during the non-injection phase, thereby avoiding unnecessary pressure loss and injector malfunction. Conversely, when the cutting-off steel ball 5 moves away from the throttling section, the internal channel opens rapidly, allowing high-pressure oil to quickly and smoothly enter the accumulator chamber 12, ensuring that the injector can accumulate high-pressure fuel in a timely manner when needed. This design utilizes the wear resistance and high-pressure self-sealing characteristics of the steel ball 5, improving the valve's response speed and sealing reliability, while simplifying the valve structure, reducing manufacturing costs and maintenance difficulty, and ensuring the stability and durability of the injector under high-pressure operating conditions.

[0024] In this embodiment, the flow limiting valve assembly also includes a flow limiting valve spring 7. The flow limiting valve spring 7 is installed within the volume chamber and located after the cut-off steel ball 5. In its installed state, the flow limiting valve spring 7 is in a pre-compressed state, and the cut-off steel ball 5 tends to move away from the choke point under the elastic force of the flow limiting valve spring 7. Specifically, the flow limiting valve spring 7 is an elastic element whose main function is to provide a continuous elastic force to drive the cut-off steel ball 5 to move in a specific direction. The flow limiting valve spring 7 is typically made of high-strength, fatigue-resistant elastic material, such as stainless steel or alloy steel, and can be designed as a helical compression spring, wave spring, or conical spring to adapt to different space constraints and mechanical requirements. In this embodiment, the flow limiting spring 7 is installed within the volume chamber B6, specifically in the latter section of the volume chamber (i.e., the chamber corresponding to the cut-off point) and extends into the former section of the volume chamber to abut against the surface of the cut-off steel ball 5. During installation, the flow restrictor spring 7 is pre-compressed to a certain degree, ensuring it maintains a preset elastic force even when the injector is not operating or in a specific state. This pre-compression guarantees that the flow restrictor spring 7 can provide immediate and stable thrust, avoiding lag in its initial response. Therefore, under the elastic force of the flow restrictor spring 7, the cut-off steel ball 5 is continuously pushed away from the cut-off section, thus tending to keep the internal channel open.

[0025] Thus, in this technical solution, the introduction of the flow-limiting valve spring 7 provides an active restoring force for the cut-off steel ball 5. Under normal operating conditions, the preload elastic force of the flow-limiting valve spring 7 can quickly and reliably push the cut-off steel ball 5 away from the choke point, ensuring the continuous opening of the inner channel, so that high-pressure oil can continuously and smoothly enter the accumulator chamber 12. When the injector malfunctions and injects too much oil, the accumulator chamber 12 is not replenished with oil in time, resulting in a pressure drop. At this time, the pressure in the volume chamber B6 drops, and the pressure in the volume chamber A4 is greater than the combined force of the pressure in the volume chamber B6 and the elastic force of the flow-limiting valve spring 7. The steel ball 5 falls to the choke point, the flow-limiting valve assembly closes, and the injector stops injecting oil. After the oil injection returns to normal, as the accumulator chamber 12 is filled with oil, the pressure in the volume chamber A4, the pressure in the volume chamber B6, and the elastic force of the flow-limiting valve spring 7 re-establish a pressure balance relationship. Under the action of the elastic force of the flow-limiting valve spring 7, the cut-off steel ball 5 moves away from the choke point and returns to the normal operating position. This effectively solves the problem of response lag or incomplete reset that may be caused by relying solely on the fluid pressure difference to drive the cut-off steel ball 5, and significantly improves the response speed and working stability of the injector in the open state. Furthermore, the continuous action of the flow-limiting valve spring 7 helps prevent the cut-off steel ball 5 from getting stuck due to friction or other resistance under specific operating conditions, further ensuring the reliability and efficiency of the injector operation. The specific elastic force of the flow-limiting valve spring 7 can be selected according to the actual system pressure and the specific value of the pressure difference when the cut-off action is required, which is understandable to those skilled in the art and will not be elaborated here.

[0026] In this embodiment, the flow restrictor assembly also includes a filter element 9. The rear part of the inner channel is a filter chamber, and the filter element 9 is installed in the filter chamber of the inner channel. Specifically, the filter element 9 is a device for removing solid particulate impurities from a fluid. It is typically made of a filter material with a specific pore size, such as a wire mesh, sintered metal, cellulose, or polymer membrane. Its function is to allow fuel to pass through while trapping solid impurities in the fuel, thereby purifying the fuel. The filter element 9 is installed inside the flow restrictor body 11 to prevent large particulate impurities from entering and causing abnormal injector operation. The rear part of the inner channel is designed as a filter chamber. The filter chamber is part of the inner channel of the valve body 11, and its structure and dimensions are optimized to provide a stable installation space and working environment for the filter element 9. The filter chamber ensures that the fuel can flow sufficiently through the filter element 9 before entering the core working area of ​​the flow restrictor assembly, thereby achieving effective filtration.

[0027] In this embodiment, the radial dimension at the end of the inner channel is reduced to form a throttling orifice 14, and the filter chamber and the throttling orifice 14 are connected by a flared structure. Specifically, the throttling orifice 14 is a narrow channel formed after the radial dimension at the end of the inner channel is reduced. Its main function is to limit the flow rate of high-pressure fuel, thereby controlling the speed and pressure of fuel entering the accumulator chamber 12. This prevents pressure overshoot in the entire system during the filling and releasing process of the accumulator chamber 12, while ensuring the stability of the pressure in the B6 volume chamber and preventing abnormal closure of the flow restrictor valve. As a preferred embodiment, the throttling orifice 14 in this embodiment is a cylindrical channel with a specific diameter and length opened on the end face of the valve body 11. Its machining accuracy directly affects the accuracy of fuel metering. The flared structure is a transition structure with a gradually narrowing cross-sectional shape, used here to connect the filter chamber and the throttling orifice 14. This structure can provide a smooth flow channel transition, avoiding severe eddies, cavitation, or fluid separation at the point of abrupt change in cross-section. The introduction of the throttle orifice 14 helps to maintain the stability of the pressure inside the accumulator chamber 12, thereby improving the response speed of the injector and the accuracy of fuel injection.

[0028] In this embodiment, the high-pressure fuel inlet channel 2 is composed of multiple parallel fuel inlet branches. Specifically, there are two fuel inlet branches in this embodiment, with each end of any one branch connected to the fuel inlet and the volume chamber, respectively. By configuring the high-pressure fuel inlet channel 2 with this multi-parallel fuel inlet structure, multiple parallel fuel inlet paths are essentially formed. This design is to keep the flow restrictor valve in a normally open state. Furthermore, by designing the high-pressure fuel inlet channel 2 as composed of multiple parallel fuel inlet branches, the effective flow cross-sectional area of ​​the high-pressure fuel is significantly increased, thereby effectively reducing the flow resistance of the fuel during its entry into the accumulator chamber 12. This allows the high-pressure fuel to quickly fill the accumulator chamber 12 with a higher flow rate and a more sufficient flow, solving the problem of insufficient fuel supply or low filling efficiency that may be caused by a single fuel inlet channel. Especially when the injector needs to respond quickly or perform high-flow injection, multiple parallel fuel inlet branches can ensure that the accumulator chamber 12 receives a stable and sufficient fuel supply, thereby improving the filling efficiency of the accumulator chamber 12 and the response speed and operational stability of the injector.

[0029] In this embodiment, a locking connecting sleeve 10 is also included. The two ends of the locking connecting sleeve 10 are respectively fitted onto the rear end of the oil inlet block 1 and the front end of the device body 13, so that the oil inlet block 1 and the device body 13 form a detachable connection. Specifically, the locking connecting sleeve 10 is a sleeve-shaped connector with internal threads at both axial ends. The locking connecting sleeve 10 is connected to the oil inlet block 1 by a reverse thread, and the locking connecting sleeve 10 is connected to the device body 13 by a positive thread, so that the device body 13 and the oil inlet block 1 form a detachable connection.

[0030] This embodiment also includes high-pressure seal I 15 and high-pressure seal II 16. High-pressure seal I 15 is located at the contact surface between the rear end face of the oil inlet block 1 and the valve body 11, and high-pressure seal II 16 is located at the contact surface between the rear end face of the valve body 11 and the device body 13. Specifically, both high-pressure seal I 15 and high-pressure seal II 16 are seals used to prevent fluid leakage from the connection interface in a high-pressure fluid environment. High-pressure seal I 15 is specifically used to seal the connection interface between the oil inlet block 1 and the valve body 11 (i.e., the interface where the rear end face of the oil inlet block 1 contacts the valve body 11 and closes the connection position after installation); high-pressure seal II 16 is specifically used to seal the connection interface between the valve body 11 and the device body 13 (i.e., the interface where the rear end face of the valve body 11 contacts the device body 13 and closes the connection position after installation). In a preferred embodiment, the high-pressure seal I 15 between the valve body 11 and the inlet block 1 adopts a planar compression seal, and the high-pressure seal II 16 between the valve body 11 and the injector body 13 adopts a conical and spherical compression seal. Simultaneously, in conjunction with the bidirectional threaded connection structure of the locking sleeve 10, the operator can achieve a compression seal by turning the locking sleeve 10. The introduction of these two high-pressure seals not only maintains precise pressure control within the injector, preventing performance degradation and safety hazards caused by fuel leakage, but also, combined with the detachable connection provided by the locking sleeve 10, allows for convenient disassembly and reassembly of the injector during maintenance and repair, while ensuring the reliability of the seal after reassembly, significantly improving the overall operational stability and service life of the injector.

[0031] In this embodiment, a leakage oil channel 3 is provided inside the oil inlet block 1. The gap between the oil inlet block 1, valve body 11, device body 13, and locking connecting sleeve 10 constitutes a leakage oil cavity, which is connected to the oil inlet through the leakage oil channel 3. Specifically, the leakage oil channel 3 refers to a channel pre-designed and machined inside the oil inlet block 1. Its main function is to collect and guide the trace amounts of leaked oil that may be generated inside the injector. The leakage oil channel 3 can be designed as an axial or inclined hole according to the structural characteristics of the oil inlet block 1. Its cross-sectional shape can be circular, elliptical, or irregular to adapt to different oil flow rates and structural space constraints. By setting the leakage oil channel 3, it is possible to ensure that the leaked oil is effectively discharged, avoiding accumulation in unexpected areas, thereby maintaining the stability of the internal pressure of the injector and the normal operation of each component. At the same time, the leakage oil cavity refers to the internal space that is naturally formed or generated through a specific structural design when multiple components such as the oil inlet block 1, valve body 11, device body 13, and locking connecting sleeve 10 cooperate and connect with each other. These gaps are typically due to component fit tolerances or small clearances reserved for ease of assembly. The leakage oil chamber serves as a buffer and collection area for leaked oil, effectively collecting oil seeping from high-pressure areas and providing an inlet for leakage oil passage 3, ensuring that leaked oil is collected and directed to a pre-set discharge path. The oil collected in the leakage oil chamber is guided through the pre-set leakage oil passage 3 to the inlet on the inlet block 1. The inlet is the interface connecting the injector to the external fuel supply system. Returning leaked oil to the inlet allows it to re-enter the fuel circulation system, achieving oil recycling and preventing oil loss or environmental pollution. Simultaneously, this design ensures the cleanliness and functional stability of the injector's internal components, preventing leaked oil from corroding or clogging other precision parts. As a preferred method, the leakage oil channels 3 in this embodiment are two inclined and symmetrically arranged channels that connect the annular chamber formed by the oil inlet block 1, the valve body 11, and the device body 13. All leakage from other areas eventually flows into this area and is then discharged to the oil inlet through the two leakage oil channels 3, so as to realize the recycling and reuse of the oil.

[0032] In this embodiment, the flow restrictor assembly also includes an adjusting shim 8, which is installed at the end of the volume chamber. One end of the flow restrictor spring 7 abuts against the adjusting shim 8, and the other end abuts against the cut-off steel ball 5. In this embodiment, by introducing the adjusting shim 8, the elastic force of the flow restrictor spring 7 is adjusted. Simultaneously, the adjusting shim 8, in cooperation with the flow restrictor spring 7, can axially limit the filter element 9 within the filter chamber. Specifically, by changing the thickness or number of adjusting shims 8, the initial compression of the flow restrictor spring 7 can be easily changed, thereby precisely controlling the preload force of the flow restrictor spring 7 acting on the cut-off steel ball 5. This precise preload adjustment capability allows the opening pressure and response characteristics of the flow restrictor assembly to be finely matched and optimized according to actual needs. For example, it can compensate for the influence of machining tolerances of the flow restrictor spring 7 or valve body 11, ensuring the consistency of performance between different injectors; it can also adjust the response speed of the flow restrictor assembly according to different fuel pressures or injection strategies, thereby improving the accuracy and efficiency of fuel injection. Therefore, the introduction of the adjusting shim 8 significantly improves the adjustability, stability and reliability of the injector performance.

[0033] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0034] The above descriptions are merely embodiments of the present invention. Commonly known structures and characteristics are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are aware of all existing technologies in that field, and have the ability to apply conventional experimental methods prior to that date. Those skilled in the art can, under the guidance of this application, improve and implement this solution in combination with their own capabilities. Some typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention. These should also be considered within the scope of protection of the present invention, and will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A large-capacity accumulator injector, characterized in that: The device includes an oil inlet block, a body, and a flow limiting valve assembly. The oil inlet block and the body are coaxially arranged and interconnected. The oil inlet block is provided with an oil inlet port and a high-pressure oil inlet channel. The high-pressure oil inlet channel is arranged along the axial direction of the oil inlet block. Multiple oil inlets are arranged along the circumference of the oil inlet block, and each oil inlet extends radially along the oil inlet block and communicates with the high-pressure oil inlet channel. The body is provided with a pressure accumulator chamber along its own axial direction. The high-pressure oil inlet channel is connected to the pressure accumulator chamber. The flow limiting valve assembly is arranged at the connection position between the high-pressure oil inlet channel and the pressure accumulator chamber. The flow limiting valve assembly is used to connect or block the connection between the high-pressure oil inlet channel and the pressure accumulator chamber.

2. The large-capacity accumulator injector according to claim 1, characterized in that: The flow-limiting valve assembly includes a valve body and a cutting-off steel ball disposed within the valve body. The front end of the valve body is inserted into the oil inlet block, and the rear end of the valve body is inserted into the device body. The valve body has a through-hole inner channel along its central axis. The high-pressure oil inlet channel is connected to the accumulator chamber through the inner channel. The front part of the inner channel is a volume chamber, and the volume chamber is provided with a flow-blocking part. The flow-blocking part is a trumpet-shaped structure with its radial dimensions gradually decreasing from front to back. The cutting-off steel ball is disposed in the volume chamber and located in front of the flow-blocking part. The cutting-off steel ball can be driven to move axially and abut against the flow-blocking part to block the inner channel. The cutting-off steel ball can also be driven to move axially away from the flow-blocking part to connect the high-pressure oil inlet channel with the accumulator chamber.

3. A large-capacity accumulator injector according to claim 2, characterized in that: The flow limiting valve assembly also includes a flow limiting valve spring, which is installed in the volume cavity and located after the cut-off steel ball. The flow limiting valve spring is in a pre-compressed state when installed, and the cut-off steel ball tends to move away from the cut-off part under the action of the elastic force of the flow limiting valve spring.

4. A large-capacity accumulator injector according to claim 2, characterized in that: The flow limiting valve assembly also includes a filter element, and the rear part of the inner channel is a filter chamber, with the filter element installed in the filter chamber of the inner channel.

5. A large-capacity accumulator injector according to claim 4, characterized in that: The radial dimension at the end of the inner channel is reduced to form a throttling orifice, and the filter cavity and the throttling orifice are connected by a flared structure.

6. A large-capacity accumulator injector according to claim 1, characterized in that: The high-pressure oil inlet channel consists of multiple parallel oil inlet branches.

7. A large-capacity accumulator injector according to claim 2, characterized in that: It also includes a locking connecting sleeve, the two ends of which are respectively sleeved on the rear end of the oil inlet block and the front end of the device body, so that the oil inlet block and the device body form a detachable connection.

8. A large-capacity accumulator injector according to claim 7, characterized in that: It also includes high-pressure seal I and high-pressure seal II. High-pressure seal I is located at the contact surface between the rear end face of the oil inlet block and the valve body, and high-pressure seal II is located at the contact surface between the rear end face of the valve body and the device body.

9. A large-capacity accumulator injector according to claim 8, characterized in that: The oil inlet block has a leakage oil passage inside. The gap between the oil inlet block, valve body, device body and locking connecting sleeve constitutes a leakage oil cavity. The leakage oil cavity is connected to the oil inlet through the leakage oil passage.

10. A large-capacity accumulator injector according to claim 3, characterized in that: The flow limiting valve assembly also includes an adjusting shim, which is installed at the end of the volume chamber. One end of the flow limiting valve spring abuts against the adjusting shim, and the other end abuts against the cut-off steel ball.

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