A small-inertia high-reliability conical valve high-pressure common rail fuel injector

Abstract

A kind of small inertia high reliability cone valve high pressure common rail oil injector, including electromagnet component, electromagnet spring, armature rod, oil injector body and spring washer, the electromagnet spring is placed between the armature rod and the spring washer in the hole in the top end of the electromagnet component, the spring washer bottom is placed with armature piece, the armature piece inside is opened with annularly distributed weight-reducing hole and oil groove, the armature piece bottom end is equipped with upper valve seat, the armature rod bottom end outer wall is equipped with double cone valve sleeve, the upper valve seat bottom end is connected with shunt plate, the shunt plate bottom end is connected with lower valve seat.The hydraulic pressure greatly reduced by double cone valve sleeve, the pre-tightening force of electromagnet spring is reduced, and then the suction requirement of electromagnet can be reduced, the manufacturing cost of electromagnet can be reduced, the heating in the working process of electromagnet can be reduced, the working reliability and service life of electromagnet can be improved.

Description

Technical Field

[0001] This invention relates to the field of fuel injector technology, specifically a cone valve high-pressure common rail fuel injector. Background Technology

[0002] Existing common rail injector assemblies, such as Figure 1 As shown, it includes an electromagnet component 1, an electromagnet spring 2, an armature rod 3, an armature plate 4, an upper valve seat 5, an upper armature seat 6A, a lower valve seat 7, an injector body 8, a push rod 9, a nozzle spring 10, a transition block 11, a nozzle needle valve body 12, a nozzle needle valve stem 13, a flow divider 14, and a nozzle gasket 15. The lift of the nozzle needle valve stem 13 is controlled by the push rod 9. The upper outer cylinder of the push rod 9 is paired with the lower hole 83 of the injector body. The upper end of the nozzle spring 10 is limited by the nozzle gasket 15.

[0003] In the existing injector assembly, because the armature rod 3 is constantly subjected to upward high-pressure hydraulic force, the preload of the electromagnet spring 2 must be greater than the high-pressure hydraulic force on the armature rod 3 when the injector is not working to meet the static sealing conditions. However, when the injector is to work, the attraction force of the electromagnet component 1 must be greater than the preload force of the electromagnet spring 2 to allow the armature rod 3 to move upward. In the existing injector structure, the force-bearing cross section of the armature rod 3 is the maximum diameter of the armature rod 3. Therefore, in the existing injector structure, the armature rod 3 is an integral structure with a conical structure at its lower end. The armature rod 3 requires mating with the upper armature seat 6A and the lower valve seat 7. It is relatively long and heavy, resulting in a large attraction force on the electromagnet component 1. Consequently, the current passing through the electromagnet component 1 is large, and both the preload force of the electromagnet spring 2 and the required electromagnet attraction force are too large. This leads to the following disadvantages:

[0004] (1) The requirement for greater attraction force will increase the difficulty of manufacturing electromagnets;

[0005] (2) The greater suction force required will increase the heat generated when the electromagnet is working, which will increase the malfunction of the electromagnet and reduce its service life.

[0006] (3) Excessive preload will increase wear on the valve stem, upper armature seat and lower valve seat during movement, which will result in deterioration of performance and reliability.

[0007] On the other hand, since the upper section of the limit rod 9 of the control nozzle needle valve rod 13 is paired with the injector body 8, it is not only difficult to process and costly, but also often gets stuck due to impurities in the oil, causing the entire injector to malfunction and have poor reliability. Summary of the Invention:

[0008] The purpose of this invention is to provide a low-inertia, high-reliability cone valve high-pressure common rail injector to solve the problems mentioned in the background art.

[0009] To achieve the above objectives, the present invention provides the following technical solution:

[0010] A low-inertia, high-reliability cone valve high-pressure common rail injector includes an electromagnet component, an electromagnet spring, an armature rod, an injector body, and a spring washer. The electromagnet spring is disposed between the concave end face of the electromagnet component and the spring washer, and is fitted onto the upper section of the armature rod. An armature plate is placed at the bottom of the spring washer. The injector body features a central hole at its center, a weight-reducing hole and an oil groove on its top surface, an upper valve seat at the bottom of the armature plate, a double cone valve sleeve fitted onto the lower section of the armature rod, a flow divider connected to the bottom of the upper valve seat, a lower valve seat connected to the bottom of the flow divider, a nozzle needle valve rod at the bottom of the injector body, a push rod connected to the top of the nozzle needle valve rod, a nozzle washer placed on the outside of the push rod, a nozzle spring fitted onto the upper section of the push rod, and a transition block between the lower end of the injector body and the nozzle assembly. The push rod and nozzle spring are fitted together and positioned in the central hole of the transition block.

[0011] Furthermore, the upper valve seat is provided with a top central hole, an upper guide hole, an oil storage chamber, a lower guide hole, and an upper conical hole in sequence from top to bottom at the center. The oil storage chamber is located between the upper guide hole and the lower guide hole, and the upper conical hole is located at the lower end of the lower guide hole. An oil return inclined hole is provided between the oil storage chamber and the bottom surface of the upper valve seat.

[0012] Furthermore, a lower inner groove and a lower conical hole are provided at the top center of the lower valve seat. The lower conical hole is located at the upper port of the lower inner groove. A lower oil passage is provided between the lower inner groove and the lower end face of the lower valve seat. Oil passage one and oil passage two are also provided between the upper end face and the lower end face of the lower valve seat.

[0013] Furthermore, the double-cone valve sleeve includes a guide hole, an upper guide post, a lower guide post, an upper conical surface, and a lower conical surface arranged coaxially. The upper conical surface is located at both ends of the lower guide post. The guide hole mates with the armature rod assembly. The upper guide post mates with the upper guide hole and the lower guide hole assembly. The outer diameter of the lower guide post is larger than the outer diameter of the upper guide post. The upper conical surface seals and corresponds to the oil storage cavity of the upper valve seat. The lower conical surface seals and connects with the lower conical hole of the lower valve seat.

[0014] Furthermore, the lower end face of the armature plate and the upper end face of the double cone valve sleeve are mechanically sealed together, and the armature plate, the double cone valve sleeve and the top hole form a damping cavity.

[0015] Furthermore, the lower end of the push rod contacts the upper end of the nozzle needle valve rod.

[0016] Furthermore, the push rod includes a spring post and a spring seat, the oil nozzle spring is fitted on the spring post, the lower end of the oil nozzle spring contacts the upper end face of the spring seat, and the lower end face of the spring seat contacts the upper end of the oil nozzle needle valve rod.

[0017] Furthermore, the top surface of the armature plate is provided with three or more weight-reducing holes and three or more oil grooves evenly distributed along the circumference, and the weight-reducing holes and oil grooves are distributed at intervals.

[0018] Furthermore, the weight-reducing hole is a blind hole.

[0019] Furthermore, clearance grooves are provided at intervals along the axis in the guide hole to reduce the actual contact area with the armature rod.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] (i) By modifying the existing integral armature rod into a split assembly structure, the control of the common rail injector's inlet end only requires moving the double cone valve sleeve up and down. The force required to move the double cone valve sleeve is much smaller than the force required to move the armature rod and the double cone valve sleeve assembly. The actual force-bearing area of ​​the double cone valve sleeve bearing the high-pressure oil pressure in the lower inner groove of the lower valve seat is reduced, thus reducing the hydraulic pressure borne by the double cone valve sleeve. This reduces the preload of the electromagnet spring, thereby reducing the electromagnet's attraction force requirement and manufacturing cost. The reduced attraction force requirement also reduces the heat generated during the electromagnet's operation, improving its reliability and service life. The reduced preload of the electromagnet spring on the lower valve seat reduces the impact force and wear on the lower valve seat during operation, improving the stability and reliability of the injector's inlet end and extending the service life of the injector assembly.

[0022] (ii) Due to the improved structure of the lift control component of the nozzle needle valve rod, a push rod limit is adopted. The push rod and the injector body are fitted with a gap, which does not require a guide. Therefore, the jamming between the two in the existing structure is eliminated from the structure. This not only reduces the machining accuracy of the push rod and the injector body and reduces the machining cost, but also eliminates the jamming defect. It can greatly improve the stability and reliability of the injector's oil outlet end, thereby extending the service life of the injector assembly. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of an existing cone valve high-pressure common rail injector;

[0024] Figure 2 This is a schematic diagram of the structure of the present invention;

[0025] Figure 3 This is a schematic diagram of the injector body.

[0026] Figure 4 A schematic diagram of the low-damping control valve assembly for oil inlet;

[0027] Figure 5 A schematic diagram of the assembly structure between the armature rod, armature plate, and double cone valve sleeve;

[0028] Figure 6 This is a schematic diagram of the structure of a double cone valve sleeve;

[0029] Figure 7 This is a schematic diagram of the armature plate.

[0030] Figure 8 for Figure 7 Top view;

[0031] Figure 9 This is a schematic diagram of the upper valve seat.

[0032] Figure 10 This is a schematic diagram of the lower valve seat.

[0033] Figure 11 This is a schematic diagram of the top rod structure;

[0034] In the diagram: 1-Electromagnet component; 2-Electromagnet spring; 3-Armature rod; 4-Armature plate; 5-Upper valve seat; 6-Double cone valve sleeve; 6A-Upper armature seat; 7-Lower valve seat; 8-Injector body; 9-Push rod; 10-Nose spring; 11-Transition block; 12-Nose needle valve body; 13-Nose needle valve rod; 14-Diverter plate; 15-Nose gasket; 16-Spring gasket; 17-Damping chamber; 18-High pressure chamber; 41-Center hole; 42-Weight reduction hole; 43 - Oil groove; 51- Top center hole; 52- Upper guide hole; 53- Oil storage cavity; 54- Lower guide hole; 55- Upper conical hole; 56- Oil return inclined hole; 61- Guide hole; 62- Upper guide post; 63- Lower guide post; 64- Upper conical surface; 65- Lower conical surface; 71- Lower inner groove; 72- Lower conical hole; 73- Lower oil passage; 74- Oil passage two; 75- Oil passage one; 81- Oil inlet passage; 82- Main oil passage; 83- Lower hole; 91- Spring post; 92- Spring seat. Detailed implementation method:

[0035] A low-inertia, high-reliability cone valve high-pressure common rail injector, such as Figure 2-11As shown, the device includes an electromagnet component 1, an electromagnet spring 2, an armature rod 3, an injector body 8, and a spring washer 16. The electromagnet spring 2 is positioned between the concave end face of the electromagnet component 1 and the spring washer 16, and is fitted onto the upper section of the armature rod 3. An armature plate 4 is placed at the bottom of the spring washer 16, and a central hole 41 is formed at the center of the armature plate 4. Three weight-reducing holes 42 and three oil grooves 43 are evenly distributed circumferentially on the top surface of the armature plate 4, with the weight-reducing holes 42 and oil grooves 43 spaced apart. An upper valve seat 5 is installed at the bottom end of the armature plate 4, and a double cone valve sleeve 6 is fitted onto the lower section of the armature rod 3. A flow divider plate 14 is connected to the bottom end of the upper valve seat 5, and a lower valve seat 7 is connected to the bottom end of the flow divider plate 14. A valve is installed at the bottom end of the injector body 8. There is a nozzle needle valve stem 13, and a push rod 9 is connected to the top of the nozzle needle valve stem 13. A nozzle gasket 15 is placed on the outside of the push rod 9. A nozzle spring 10 is fitted on the upper part of the push rod 9. A transition block 11 is provided between the lower end of the injector body 8 and the nozzle assembly. After the push rod 9 and the nozzle spring 10 are fitted, they are placed in the center hole of the transition block 11. At the center of the upper valve seat 5, from top to bottom, there are a top central hole 51, an upper guide hole 52, an oil storage chamber 53, a lower guide hole 54, and an upper conical hole 55. The oil storage chamber 53 is located between the upper guide hole 52 and the lower guide hole 54. The upper conical hole 55 is located at the lower end of the lower guide hole 54. A return oil inclined hole 56 is provided between the oil storage chamber 53 and the bottom surface of the upper valve seat 5. At the center of the lower valve seat 7 The top end is provided with a lower inner groove 71 and a lower conical hole 72. The lower conical hole 72 is located at the upper port of the lower inner groove 71. A lower oil passage 73 is provided between the lower inner groove 71 and the lower end face of the lower valve seat 7. Oil passage one 75 and oil passage two 74 are also provided between the upper end face and the lower end face of the lower valve seat 7. The double cone valve sleeve 6 includes a guide hole 61, an upper guide post 62, a lower guide post 63, an upper conical surface 64, and a lower conical surface 65 arranged coaxially. The upper conical surface 64 is located at both ends of the lower guide post 63. The guide hole 61 cooperates with the armature rod 3. The upper guide post 62 cooperates with the upper guide hole 52 and the lower guide hole 54. The outer diameter of the lower guide post 63 is larger than the outer diameter of the upper guide post 62. The upper conical surface 64 corresponds to the oil storage cavity 53 of the upper valve seat 5 in a sealed manner. The lower conical hole 72 of the lower valve seat 7 is sealed and connected to the upper conical hole 62 of the armature plate 4; the lower end face of the armature plate 4 and the upper end face of the double conical valve sleeve 6 are mechanically sealed together. The armature plate 4, the double conical valve sleeve 6 and the top central hole 51 form a damping cavity 17; the lower end of the push rod 9 contacts the upper end of the nozzle needle valve rod 13; the push rod 9 includes a spring column 91 and a spring seat 92. The nozzle spring 10 is fitted on the spring column 91. The lower end of the nozzle spring 10 contacts the upper end face of the spring seat 92, and the lower end face of the spring seat 92 contacts the upper end of the nozzle needle valve rod 13; three or more weight-reducing holes 42 and three or more oil grooves 43 are evenly provided circumferentially on the top surface of the armature plate 4, and the weight-reducing holes 42 and oil grooves 43 are spaced apart. The weight-reducing holes 42 can be through holes or blind holes.

[0036] In order to further reduce the sliding friction between the armature rod 3 and the double cone valve sleeve 6, clearance grooves are provided at intervals along the axis in the guide hole 61 to reduce the actual contact area with the armature rod 3.

[0037] The working principle of this invention is:

[0038] High-pressure oil enters the lower oil passage 73 and lower inner groove 71 of the lower valve seat 7 sequentially through the oil inlet passage 81 of the injector body 8. When the electromagnet component 1 is not energized, under the preload of the electromagnet spring 2, the conical surface of the double-cone valve sleeve 6 mechanically seals with the lower conical opening 72 of the lower valve seat 7, preventing high-pressure oil from entering the high-pressure chamber of the nozzle assembly. Under the preload of the nozzle spring 10, the nozzle needle valve rod 13 mechanically seals with the nozzle needle valve body 12, and the injector does not spray oil. When the electromagnet component 1 is energized, due to the electromagnetic force, the armature plate... 4. As the double cone valve sleeve 6 moves upward under the action of high-pressure oil in the lower inner groove 71, the cone surface of the double cone valve sleeve 6 leaves the lower cone opening 72 of the lower valve seat 7. The high-pressure oil enters the channel of the distributor plate 14, and then along the channel, the oil passage 75 of the lower valve seat 7, and the main oil passage 82 of the injector body 8, into the high-pressure chamber 18 of the nozzle assembly. When the hydraulic pressure of the high-pressure chamber 18 on the nozzle needle valve rod 13 overcomes the preload of the nozzle spring 10, the nozzle needle valve rod 13 moves upward, the injector sprays oil, and the upper valve seat 5 provides control for the oil circuit of the device. For manufacturing purposes, the armature rod 3 and the double cone valve sleeve 6 are paired components. The outer circle of the double cone valve sleeve 6 is paired with the upper guide hole 52 and the lower guide hole 54 of the upper valve seat 5, which increases the accuracy of the device operation. The actual force-bearing area of ​​the double cone valve sleeve 6 bearing the high-pressure oil pressure of the lower inner groove 71 of the lower valve seat 7 is greatly reduced, and the hydraulic pressure borne by the double cone valve sleeve 6 is greatly reduced. This can reduce the preload of the electromagnet spring 2, and the preload of the electromagnet spring 2 borne by the lower valve seat 7 can be reduced, which can reduce the impact force of the lower valve seat 7 during operation. To improve the stability and reliability of the injector and extend the service life of the injector assembly, the armature plate 4, the double cone valve sleeve 6, and the upper cone hole 55 are integrated to form a damping cavity 17. The end face of the push rod 9 is in mechanical contact with the upper end face of the nozzle needle valve rod 13. The lift of the nozzle needle valve rod 13 is limited by the push rod 9, which can reduce costs and reduce the high-pressure sealing surface, thereby reducing the risk of leakage caused by the high-pressure sealing surface. The push rod 9 does not require mating parts, has low manufacturing difficulty, and can reduce processing and use costs.

[0039] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A low-inertia, high-reliability cone valve high-pressure common rail injector, comprising an electromagnet component (1), an electromagnet spring (2), an armature rod (3), an injector body (8), and a spring washer (16), wherein the electromagnet spring (2) is disposed between the concave end face of the electromagnet component (1) and the spring washer (16), and is fitted onto the upper section of the armature rod (3), and an armature plate (4) is placed at the bottom of the spring washer (16), characterized in that, A central hole (41) is provided at the center of the armature plate (4). A weight reduction hole (42) and an oil groove (43) are provided on the top surface of the armature plate (4). An upper valve seat (5) is installed at the bottom end of the armature plate (4). A double cone valve sleeve (6) is fitted on the lower section of the armature rod (3). A flow divider plate (14) is connected to the bottom end of the upper valve seat (5). A lower valve seat (7) is connected to the bottom end of the flow divider plate (14). A nozzle needle valve rod (13) is provided at the bottom end of the injector body (8). A push rod (9) is connected to the top end of the nozzle needle valve rod (13). A nozzle gasket (15) is placed on the outside of the push rod (9). A sleeve is fitted on the upper section of the push rod (9). The injector body (8) is equipped with a nozzle spring (10). A transition block (11) is provided between the lower end of the injector body (8) and the nozzle assembly. The push rod (9) and the nozzle spring (10) are fitted together and placed in the center hole of the transition block (11). Three or more weight-reducing holes (42) and three or more oil grooves (43) are evenly provided circumferentially on the top surface of the armature plate (4), and the weight-reducing holes (42) and oil grooves (43) are spaced apart. The upper valve seat (5) is provided with a top center hole (51), an upper guide hole (52), an oil storage chamber (53), a lower guide hole (54), and an upper conical hole (55) in the center from top to bottom. The oil storage chamber (53) An upper conical hole (55) is provided between the upper guide hole (52) and the lower guide hole (54), and an oil return inclined hole (56) is provided between the oil storage cavity (53) and the bottom surface of the upper valve seat (5). A lower inner groove (71) and a lower conical hole (72) are provided at the top center of the lower valve seat (7), and the lower conical hole (72) is provided at the upper end of the lower inner groove (71). A lower oil passage (73) is provided between the lower inner groove (71) and the lower end face of the lower valve seat (7). Oil passage one (75) and oil passage two (74) are also provided between the upper end face and the lower end face of the lower valve seat (7). The double cone valve sleeve (6) includes a guide hole (61), an upper guide post (62), a lower guide post (63), an upper cone surface (64), and a lower cone surface (65) arranged coaxially. The upper cone surface (64) is located at both ends of the lower guide post (63). The guide hole (61) is matched with the armature rod (3). The upper guide post (62) is matched with the upper guide hole (52) and the lower guide hole (54). The outer diameter of the lower guide post (63) is larger than the outer diameter of the upper guide post (62). The upper cone surface (64) is sealed and corresponds to the oil storage cavity (53) of the upper valve seat (5). The lower cone surface (65) is sealed and connected to the lower cone hole (72) of the lower valve seat (7).

2. The low-inertia, high-reliability cone valve high-pressure common rail injector according to claim 1, characterized in that, The lower end face of the armature plate (4) and the upper end face of the double cone valve sleeve (6) are mechanically sealed together. The armature plate (4), the double cone valve sleeve (6) and the top hole (51) form a damping cavity (17).

3. The low-inertia, high-reliability cone valve high-pressure common rail injector according to claim 1, characterized in that, The lower end of the push rod (9) is in contact with the upper end of the nozzle needle valve rod (13).

4. The low-inertia, high-reliability cone valve high-pressure common rail injector according to claim 1, characterized in that, The push rod (9) includes a spring post (91) and a spring seat (92). The oil nozzle spring (10) is fitted on the spring post (91). The lower end of the oil nozzle spring (10) contacts the upper end face of the spring seat (92), and the lower end face of the spring seat (92) contacts the upper end of the oil nozzle needle valve rod (13).

5. The low-inertia, high-reliability cone valve high-pressure common rail injector according to claim 1, characterized in that, The weight reduction hole (42) is a blind hole.

6. The low-inertia, high-reliability cone valve high-pressure common rail injector according to claim 1, characterized in that, A clearance groove is provided at intervals along the axis in the guide hole (61) to reduce the actual contact area with the armature rod (3).

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