阅读说明：本技术 一种调压弹簧上置式喷油器 (Pressure regulating spring overhead type oil sprayer ) 是由 范永新 秦龙 左照伟 韩彪 刘建石 于 2021-08-19 设计创作，主要内容包括：本发明公开了一种调压弹簧上置式喷油器,包括喷油器壳体、电磁控制阀、针阀以及控制杆；所述控制杆包括等径结构的上承压段和等径结构的下承压段,其中上承压段的端部插装在控制阀套内,下承压段的端部抵接针阀升程调整垫；在控制阀套安装腔室内控制阀套下端面至控制阀套安装腔室底部之间形成调压空间；在调压空间内所述控制杆的上承压段上套装有调压弹簧,调压弹簧的上部与控制阀套的下端面抵接,调压弹簧的下端所述上承压段上设有环槽,所述凹槽内设有开口挡圈,所述调压弹簧的下端部与开口挡圈之间设有弹簧力调整垫；上述控制杆安装腔为等径结构。本发明加工便利、降低加工成本,同时的可以最大程度保证控制杆与针阀不会有脱开的情况发生。(The invention discloses a pressure regulating spring overhead type oil sprayer which comprises an oil sprayer shell, an electromagnetic control valve, a needle valve and a control rod, wherein the electromagnetic control valve is arranged on the oil sprayer shell; the control rod comprises an upper pressure-bearing section with an equal-diameter structure and a lower pressure-bearing section with an equal-diameter structure, wherein the end part of the upper pressure-bearing section is inserted into the control valve sleeve, and the end part of the lower pressure-bearing section is abutted against the needle valve lift adjusting pad; a pressure regulating space is formed between the lower end surface of the control valve sleeve in the control valve sleeve mounting cavity and the bottom of the control valve sleeve mounting cavity; a pressure regulating spring is sleeved on the upper pressure bearing section of the control rod in the pressure regulating space, the upper part of the pressure regulating spring is abutted against the lower end face of the control valve sleeve, the upper pressure bearing section at the lower end of the pressure regulating spring is provided with a ring groove, a split retainer ring is arranged in the groove, and a spring force adjusting pad is arranged between the lower end part of the pressure regulating spring and the split retainer ring; the control rod installation cavity is of an equal-diameter structure. The invention has convenient processing, reduces the processing cost and can ensure that the control rod and the needle valve are not separated to the maximum extent.)

1. A pressure regulating spring overhead type oil sprayer comprises an oil sprayer shell; an electromagnetic control valve installation cavity, a control valve sleeve installation cavity and a control rod installation cavity are sequentially arranged in the fuel injector shell, one end of the fuel injector shell is provided with an electromagnetic control valve, the other end of the fuel injector shell is provided with a needle valve, and a control rod for connecting the electromagnetic control valve and the needle valve is arranged in the fuel injector shell; one end of the control rod is inserted into a control valve sleeve of the electromagnetic control valve; the other end of the control valve rod extends to a needle valve rod of the needle valve, and a needle valve lift adjusting pad is arranged between the control valve rod and the needle valve rod; wherein the end part of the upper pressure-bearing section is inserted in the control valve sleeve, and the end part of the lower pressure-bearing section is abutted against the needle valve lift adjusting pad;

a pressure regulating space is formed between the lower end surface of the control valve sleeve in the control valve sleeve mounting cavity and the bottom of the control valve sleeve mounting cavity; a pressure regulating spring is sleeved on the upper pressure bearing section of the control rod in the pressure regulating space, the upper part of the pressure regulating spring is abutted against the lower end face of the control valve sleeve, the upper pressure bearing section at the lower end of the pressure regulating spring is provided with a ring groove, a split retainer ring is arranged in the groove, and a spring force adjusting pad is arranged between the lower end part of the pressure regulating spring and the split retainer ring; the control rod installation cavity is of an equal-diameter structure.

2. The pressure regulating spring-top fuel injector of claim 1, characterized in that: the lower end face of the lower pressure bearing section is provided with a groove, and the needle valve lift adjusting pad is installed in the groove.

3. The pressure regulating spring-top fuel injector of claim 1, characterized in that: the lower end part of the lower pressure-bearing section is sleeved with a guide sleeve, the needle valve lift adjusting pad is installed in the guide sleeve, and a needle valve rod is inserted into the guide sleeve and is abutted against the needle valve lift adjusting pad.

4. The pressure regulating spring-top fuel injector of claim 1, characterized in that: the valve rod of the needle valve is inserted into the guide sleeve by 0.5-1 mm.

5. The pressure regulating spring-top fuel injector of claim 1, characterized in that: the diameter of the control rod installation cavity is phi 5.6-phi 7.3 mm; the diameter of the control valve sleeve installation cavity is phi 10 mm; the diameter of the pressure regulating space is phi 8.2 mm.

Technical Field

The invention belongs to the technical field of common rail fuel injection systems, and particularly relates to a pressure regulating spring overhead fuel injector.

Background

As is well known, a common rail injection type oil supply system is composed of a high pressure oil pump, a common oil supply pipe, an oil injector, an Electronic Control Unit (ECU) and some pipeline pressure sensors, wherein each oil injector in the system is connected with the common oil supply pipe through a respective high pressure oil pipe, and the common oil supply pipe performs a hydraulic pressure accumulation function on the oil injector. When the high-pressure oil pump works, fuel oil is conveyed to the public oil supply pipe by the high pressure oil pump, the high-pressure oil pump, the pressure sensor and the ECU form closed-loop work, the oil pressure in the public oil supply pipe is accurately controlled, and the phenomenon that the oil supply pressure changes along with the rotating speed of an engine is thoroughly changed.

Referring to fig. 3, a conventional common rail injector pressure regulating spring is disposed at a needle valve connecting end (a small end of an injector housing) in an injector housing 1, and on a control rod at the needle valve connecting end, one end is supported on a spring seat 11 placed at an inner step surface of a hole, the other end is supported on an upper end surface of a bush, and the inner step surface of the bush is supported on the upper end surface of a needle valve 3. Therefore, the pressure of the pressure regulating spring acts on the moving member needle valve stem. In addition, the inner part of the bushing 12 is a stepped hole which is in clearance fit with the control rod and the needle valve rod respectively. And, a needle lift adjusting pad 5 is disposed between the control lever and the needle valve stem to precisely adjust the lift of the needle valve.

The prior art has the following defects: because the diameters of the two ends of the control rod are not consistent, the forming centerless grinder with higher precision is needed to ensure the coaxiality of the control rod, and when the length of the control rod is changed, the grinding wheel and the supporting plate need to be correspondingly modified, so the processing cost is higher, and the model change is inconvenient. Two inner holes and inner step surfaces of the bushing are ground, so that the machining difficulty is high, and the cost is high. The spring hole at the small end of the injector shell needs to be clamped at the large end for processing, when the injector shell is longer, the swinging amount is larger during processing, the processing difficulty is large, and the cost is higher. The structure of integrating the three positions of the control rod, the bushing and the spring hole at the small end of the injector shell has the advantages of high processing difficulty and high processing cost of the traditional injector.

In addition, the pressure of the pressure regulating spring acts on the valve rod of the needle valve, and the situation that the control rod is separated from the valve rod of the needle valve in the oil injection opening or closing process is possible to occur at low rail pressure, so that the needle valve is not stably seated, and the oil injection quantity fluctuates.

Therefore, the pressure regulating spring upper-mounted fuel injector is convenient to process, low in cost and capable of ensuring that the control rod and the needle valve are not separated to the maximum extent.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a pressure regulating spring overhead type oil sprayer.

The invention is realized in this way, a pressure regulating spring upper-mounted fuel injector, including the fuel injector body; an electromagnetic control valve installation cavity, a control valve sleeve installation cavity and a control rod installation cavity are sequentially arranged in the fuel injector shell, one end of the fuel injector shell is provided with an electromagnetic control valve, the other end of the fuel injector shell is provided with a needle valve, and a control rod for connecting the electromagnetic control valve and the needle valve is arranged in the fuel injector shell; one end of the control rod is inserted into a control valve sleeve of the electromagnetic control valve; the other end of the control valve rod extends to a needle valve rod of the needle valve, and a needle valve lift adjusting pad is arranged between the control valve rod and the needle valve rod; wherein the end part of the upper pressure-bearing section is inserted in the control valve sleeve, and the end part of the lower pressure-bearing section is abutted against the needle valve lift adjusting pad;

a pressure regulating space is formed between the lower end surface of the control valve sleeve in the control valve sleeve mounting cavity and the bottom of the control valve sleeve mounting cavity; a pressure regulating spring is sleeved on the upper pressure bearing section of the control rod in the pressure regulating space, the upper part of the pressure regulating spring is abutted against the lower end face of the control valve sleeve, the upper pressure bearing section at the lower end of the pressure regulating spring is provided with a ring groove, a split retainer ring is arranged in the groove, and a spring force adjusting pad is arranged between the lower end part of the pressure regulating spring and the split retainer ring; the control rod installation cavity is of an equal-diameter structure.

Preferably, a groove is formed in the lower end face of the lower pressure bearing section, and the needle valve lift adjusting pad is installed in the groove.

Preferably, the lower end part of the lower pressure-bearing section is sleeved with a guide sleeve, the needle valve lift adjusting pad is installed in the guide sleeve, and a needle valve rod is inserted into the guide sleeve and is abutted against the needle valve lift adjusting pad.

Preferably, the valve rod of the needle valve is inserted into the guide sleeve by 0.5-1mm

Preferably, the diameter of the control rod installation cavity is phi 5.6-phi 7.3 mm; the diameter of the control valve sleeve installation cavity is phi 10 mm; the diameter of the pressure regulating space is phi 8.2 mm.

The invention has the advantages and technical effects that: due to the adoption of the technical scheme, the control rod can be processed by adopting a through type centerless grinding method, and the control rod is insensitive to length change, convenient to process and low in cost. The guide sleeve can be made of non-quenched and tempered steel or quenched and tempered materials, and a middle hole is drilled and reamed or finely turned, so that grinding is not needed, and the processing cost is greatly reduced. The needle valve mounting end of the oil injector shell is free of a step hole and is formed by machining from an electromagnetic control valve gun drill when the needle valve mounting end is clamped; when the electromagnetic control valve end is clamped, an inner hole machining task is omitted, and machining difficulty and cost are greatly reduced. In addition, the invention adopts the mode of arranging the pressure regulating spring upwards, the acting force of the pressure regulating spring acts on the control rod, and the control rod and the needle valve can be ensured not to be separated to the greatest extent.

Drawings

FIG. 1 is a schematic structural view of example 1 of the present invention;

FIG. 2 is a schematic structural view of example 2 of the present invention;

fig. 3 is a schematic diagram of a prior art structure.

In the figure, 1, a fuel injector shell; 1-1, installing a cavity of an electromagnetic control valve; 1-2, controlling a valve sleeve installation cavity; 1-3, a control rod installation cavity; 2. an electromagnetic control valve; 2-1, controlling a valve sleeve; 3. a needle valve; 4. a control lever; 4-1, an upper pressure-bearing section; 4-2, a lower pressure-bearing section; 4-3, a ring groove; 4-4, a groove; 5. a needle valve lift adjustment pad; 6. a pressure regulating space; 7. a pressure regulating spring; 8. a split washer; 9. a spring force adjustment pad; 10. a guide sleeve; 11. a spring seat; 12. a bushing.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Embodiment 1, please refer to fig. 1, a pressure regulating spring top-mounted fuel injector includes a fuel injector housing 1, an electromagnetic control valve 2 installed at one end of the fuel injector housing, a needle valve 3 installed at the other end of the fuel injector housing, and a control rod 4 connecting the electromagnetic control valve and the needle valve in the fuel injector housing; one end of the control rod is inserted into a control valve sleeve of the electromagnetic control valve; the other end of the control valve rod extends to a needle valve rod of a needle valve, a needle valve lift adjusting pad 5 is arranged between the control valve rod and the needle valve rod, the components form the basis of the oil injector, the working principle of the oil injector is the same as that of the oil injector in the prior art,

wherein the solenoid control valve is configured to: the fuel injector actuator controls the injection starting time and the fuel injection duration of the fuel injector so as to control the fuel injection quantity;

the needle valve is used for: the needle valve reciprocates in the needle valve body to control the start and the end of oil injection;

the control lever is used for: the transmission rod piece is used for controlling the opening and closing of the needle valve by the electromagnetic valve;

the needle valve lift adjusting pad is used for adjusting the lift of the needle valve; controlling the consistency of the fuel injection quantity of the non-ballistic region of the fuel injector;

because the diameters of the two ends of the existing control rod are not consistent, a forming centerless grinder with higher precision is needed to ensure the coaxiality of the control rod, when the length of the control rod is changed, a grinding wheel and a supporting plate need to be correspondingly modified, the processing cost is higher, and the model change is inconvenient; meanwhile, two inner holes and an inner step surface of the bushing are ground, so that the machining difficulty is high, and the cost is high. The spring hole at the small end of the injector shell needs to be clamped at the large end for processing, when the injector shell is longer, the swinging amount is larger during processing, the processing difficulty is large, and the cost is higher. The structure of integrating the three positions of the control rod, the bushing and the spring hole at the small end of the injector shell has the advantages of high processing difficulty and high processing cost of the traditional injector.

In order to facilitate processing, reduce processing cost and simultaneously ensure that the control rod and the needle valve are not separated to the maximum extent, the invention aims at the prior art to make the following improvements:

an electromagnetic control valve installation cavity 1-1, a control valve sleeve installation cavity 1-2 and a control rod installation cavity 1-3 are sequentially arranged in the fuel injector shell, wherein the control rod installation cavity is of an equal-diameter structure. Preferably, the diameter of the control rod installation cavity is phi 5.6-phi 7.3 mm; the diameter of the control valve sleeve installation cavity is phi 10 mm; the diameter of the pressure regulating space is phi 8.2 mm.

The three cavities of the oil sprayer shell are machined when the outer circle of the small end is clamped by adopting the structural design; when the outer circle of the large end (the electromagnetic control valve end) is held, no inner hole machining task is available, and the machining difficulty is reduced; meanwhile, the tip can be supported on a chamfer of an inner hole of the small end (needle valve mounting end) of the oil injector shell, so that the clamping rigidity is enhanced, and the processing precision of the excircle and the small end face of the small end of the oil injector shell is improved.

The control rod 4 comprises an upper pressure-bearing section 4-1 with an equal-diameter structure and a lower pressure-bearing section 4-2 with an equal-diameter structure, and the outer diameter of the upper pressure-bearing section is smaller than that of the lower pressure-bearing section, so that the light weight design concept is met; the control rod can be processed by adopting a through type centerless grinder, so that the processing difficulty and the cost are greatly reduced. And when the length of the control rod is changed due to the change of the model of the oil injector, the machining process of the control rod is hardly influenced. Optimally, in order to reduce the mass of the control rod, an outer circle with a smaller diameter can be arranged at one or more positions in the middle of the control rod, and the part can be finely turned before heat treatment without grinding. Wherein the end part of the upper pressure-bearing section is inserted in the control valve sleeve 2-1, and the end part of the lower pressure-bearing section is abutted against the needle valve lift adjusting pad 5; a pressure regulating space 6 is formed between the lower end surface of the control valve sleeve in the control valve sleeve mounting cavity and the bottom of the control valve sleeve mounting cavity; in the pressure regulating space, the upper pressure bearing section of the control rod is sleeved with a pressure regulating spring 7, and the pressure regulating spring is positioned by clearance fit with the excircle of the control rod. The upper part of the pressure regulating spring is abutted against the lower end face of the control valve sleeve, the lower end of the pressure regulating spring is provided with an annular groove 4-3 on the upper pressure bearing section, the annular groove is used for supporting the pressure regulating spring, and the annular groove is arranged at a certain fixed position at the upper end of the control rod and is not changed due to the change of the length of the control rod. Be equipped with split ring 8 in the recess, be equipped with spring force adjusting pad 9 between the lower tip of pressure regulating spring and the split ring for adjust pressure regulating spring's pretightning force. The spring force adjusting pads are graded according to at least 0.01mm, the numerical value of the pretightening force of the pressure adjusting spring can be accurately controlled, and the oil mass precision of the oil sprayer is improved; the central hole of the spring force adjusting pad is in clearance fit with the excircle of the control rod.

In this embodiment, preferably, the lower end part of the lower pressure-bearing section is sleeved with a guide sleeve 10 and is connected by transition fit or small interference fit; the needle valve lift adjusting pad is installed in the guide sleeve, and a needle valve rod is inserted into the guide sleeve and is abutted to the needle valve lift adjusting pad 5. The needle valve lift adjusting pad is placed in a central hole of the guide sleeve and is positioned by clearance fit with the central hole of the guide sleeve; the guide sleeve can be made of non-quenched and tempered steel or quenched and tempered materials, and a middle hole is drilled and reamed or finely turned, so that grinding is not needed, and the processing cost is greatly reduced.

Preferably, the valve rod of the needle valve is inserted into the guide sleeve by 0.5-1mm, so that the lift adjusting pad is ensured to be completely immersed into the guide sleeve and is completely in clearance fit with the guide sleeve;

in embodiment 2, referring to fig. 2, preferably, a groove 4-4 is formed in the lower end surface of the lower pressure bearing section, and the needle lift adjusting pad 5 is installed in the groove. The aperture of the groove is in clearance fit with the outer diameter of the needle lift adjusting pad to position, and at least 0.2mm of the needle lift adjusting pad extends out of the lower end face of the control rod to prevent the control rod from contacting with a needle valve rod. The other structures are the same as those of embodiment 1.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.