Flat position machining tool for needle valve

Abstract

The utility model discloses a needle valve flat position machining tool which comprises a clamp body, and an arc-shaped positioning groove is formed in the upper end of the clamp body. Two shaft holes are formed in the clamp body, and a rotating shaft is mounted in the two shaft holes; a side opening groove is formed in the clamp body, a pressing plate is installed in the side opening groove, and the rotating shaft is installed in a through hole in the middle of the pressing plate in a penetrating mode. An inclined crimping surface is arranged on the pressing plate; the pressing plate is fixedly mounted on the rotating shaft; a groove is formed in the left side of the pressing plate, and a spring is installed in the groove. A baffle block is mounted on the side surface of the clamp body through a fastener; an index plate is fixedly installed on the needle valve, and a pin hole is formed in the lower portion of the clamp body and used for installing a positioning pin. And the positioning pin is inserted into the open slot of the dividing plate. According to the needle valve flat grinding tool, the innovative index plate design is adopted, and high-precision machining of three evenly-distributed flat positions on the outer circle of a needle valve is achieved. By accurately controlling the included angle between the flat planes, the precision requirement of 60 + / -1 degrees is met, the roughness standard of Ra0.4 is met, and the performance and reliability of the oil injector needle valve are remarkably improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of fuel injector processing, in particular to a needle valve flat position processing tool. Background Art

[0002] In the manufacturing process of fuel injector products, the needle valve component with special structure is a key component. The outer circle part of the needle valve (marked as 11b) needs to form three evenly distributed flat planes during the processing, such as Figure 1 The figure shows the structure of a needle valve before machining the three flat surfaces to meet the specific requirements of product design. The machining accuracy of these flat surfaces is crucial to the performance and life of the injector.

[0003] In traditional processing methods, the flat parts on shaft parts are usually milled by milling machines. However, in this case, the processing of needle valves has some special features and challenges. First, the hardness of the needle valve after quenching is as high as HRC60, which is far beyond the hardness range of materials usually applicable to milling. Therefore, using a milling machine to process the flat parts of the needle valve is not only inefficient, but also easily causes excessive wear of the tool and reduced processing accuracy.

[0004] Secondly, the processing accuracy of the flattened plane is very high. According to the design requirements, the three flattened planes need to maintain an angle of 60°±1° between each other. Figure 2 , and the roughness of each plane needs to reach the standard of Ra0.4. However, it is difficult to ensure such high precision and surface roughness requirements when milling hard materials.

[0005] In addition, although the currently commonly used surface grinding machine processing method can achieve high processing accuracy and surface roughness, it usually adopts an upper pressure plate type tooling, which can only process two parallel flat planes at the same time and cannot meet the processing requirements of the three evenly distributed flat planes of the needle valve.

[0006] In summary, the existing processing methods have obvious limitations and deficiencies when processing the three evenly distributed flat planes of the needle valve, so it is necessary to develop a new processing method or technology to meet the high precision and special requirements of needle valve flat processing. Utility Model Content

[0007] In view of the problems existing in the prior art, the utility model provides a needle valve flat position processing tool.

[0008] The utility model is implemented as follows: a needle valve flat position processing tool, characterized in that: it includes a clamp body, the upper end of the clamp body is provided with an arc-shaped positioning groove, which is used to position the needle valve and expose the top plane of the needle valve; the clamp body is provided with two shaft holes, and the two shaft holes are equipped with rotating shafts; the clamp body is provided with a side opening groove, and a pressure plate is installed in the side opening groove, and the rotating shaft is installed in the through hole in the middle of the pressure plate; the pressure plate is provided with an inclined pressing surface; the pressure plate is fixedly installed on the rotating shaft; the left side of the pressure plate is provided with a groove, and a spring is installed in the groove; the side of the clamp body is equipped with a stopper through a fastener to limit the axial positioning of the needle valve;

[0009] On the opposite side of the stopper, a dividing plate is fixedly installed on the needle valve, and a pin hole is provided below the arc-shaped positioning groove of the clamp body for installing a positioning pin; the positioning pin passes through the opening groove of the dividing plate, and a first top screw is installed on the dividing plate to fasten the dividing plate and the needle valve together.

[0010] Further preferably, the angle between the pressing surface of the pressing plate and the vertical direction is 30°.

[0011] Further preferably, a second top screw is provided on the pressure plate at a position corresponding to the rotating shaft for fixing the rotating shaft.

[0012] Further preferably, a threaded through hole is provided at the lower portion of the pressing plate for installing a screw, and the screw is used to adjust the pressing force of the pressing plate.

[0013] Further preferably, a first top screw is provided on the dividing plate along the axial direction, and the lower end of the top screw abuts against the outer wall of the needle valve to fasten the dividing plate and the needle valve.

[0014] Further preferably, the evenly distributed open grooves on the dividing plate are used for dividing the three evenly distributed flat planes of the needle valve.

[0015] The utility model has the advantages and technical effects: the utility model adopts the above technical scheme, through the three open grooves evenly distributed on the indexing plate, they are rotated and inserted into the positioning pin in turn, and the clamping angle of the needle valve is switched at the same time. The angles of the three open grooves on the indexing plate correspond to the angles of the three flat surfaces of the needle valve, so as to process the three flat surfaces of the needle valve; the needle valve flattening tool solves the problem of how to grind the three evenly distributed flat surfaces of the needle valve on a surface grinder, and at the same time meets the quality requirement of 60°±1° between the angles of the three flat surfaces; the axial position of the needle valve is limited by the positioning block, and the pressure plate, the rotating shaft, and the screw are used to grind the three flat surfaces of the needle valve. The clamping mechanism uses the lever principle to effectively clamp the needle valve; the above-mentioned needle valve flattening tooling clamping method is simple and easy to operate, does not require manual correction of the workpiece clamping surface, reduces personnel operation errors, and has high processing efficiency; in addition, the use of flat grinding to grind three flats instead of milling the flattening method of the milling machine can meet the requirements of the flat surface roughness Ra0.4, and solves the problem of substandard milling roughness; since the cutting amount during the grinding process is small and it is a reciprocating grinding flat surface processing method, the problem of large flanging burrs on the flat edges of the needle valve can be avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of the structure of the needle valve before the outer circle is processed into three flat positions;

[0017] Figure 2 Schematic diagram of the structure of the needle valve after machining three flattened parts on the outer circle;

[0018] Figure 3 A front view of an embodiment of a three-flat-position tooling for a needle valve grinding machine of the present application;

[0019] Figure 4 A side view of an embodiment of a three-flat-position tooling for a needle valve grinding according to the present application;

[0020] Figure 5 yes Figure 3 The middle clip has a top view of the details;

[0021] Figure 6 yes Figure 3 Cross-sectional view of the center index plate;

[0022] Figure 7 yes Figure 2 Cross-sectional view of the middle needle valve;

[0023] Figure 8 This is a schematic diagram of the three-step flattening process of the outer circle of the needle valve.

[0024] In the figure, 1, clamp body; 1a, arc-shaped positioning groove; 1b, shaft hole; 1c, side opening groove; 2, pressure plate; 2-1, groove; 2a, crimping surface; 3, spring; 4, rotating shaft; 5, second top screw; 6, screw; 7, stopper; 8, positioning pin; 9, dividing plate; 10, first top screw; 11, needle valve. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail in combination with the embodiments below. It should be understood that the specific embodiments described here are only used to explain the utility model, and are not used to limit the utility model.

[0026] See also Figures 1 to 7 A needle valve flat position processing tooling includes a clamp body 1. The bottom end area of ​​the clamp body 1 is relatively wide in order to increase the contact area between the flattening tooling and the slide of the surface grinder, so as to ensure that the flattening tooling is firmly and reliably magnetically attracted to the slide; the upper end of the clamp body is provided with an arc-shaped positioning groove 1a, which is used to position the needle valve and expose the top plane of the needle valve, and does not affect the processing of the needle valve flat position by the grinding wheel. The size of the arc-shaped positioning groove 1a is designed and manufactured according to the clearance of 0.005 to 0.015 of the large outer circle of the needle valve to be processed, so as to avoid the needle valve being unable to be smoothly placed in the positioning groove 1a due to too small a clearance, and also to avoid the second and third clamping positions of the same needle valve in the positioning groove 1a being inconsistent when grinding three flat positions, which affects the consistency of the angles between the three flat positions being ground. ; The clamp body is provided with two axial holes 1b, and the rotating shaft 4 is installed in the two axial holes 1b; The clamp body is provided with a side opening groove 1c, and the pressure plate 2 is installed in the side opening groove, and the rotating shaft 4 is installed in the through hole in the middle of the pressure plate; The pressure plate is provided with an inclined crimping surface 2a; The outer contour of the pressure plate 2 is designed to ensure that after the pressure plate is assembled on the clamp body 1, the top surface of the pressure plate is flush with the top surface of the clamp body, so as to avoid the height of the top surface of the pressure plate being higher than the height of the flattened surface of the needle valve, causing the grinding wheel to interfere with the pressure plate; On the other hand, the crimping surface 2a is designed to have an angle of 30° with the vertical direction, so that the contact point between the pressure plate surface 2a and the large outer circle of the needle valve to be processed is higher than the center of the needle valve by 1 / 2 of the needle valve radius, so that the clamping force on the clamped part of the needle valve is effective and stable;

[0027] The pressing plate is fixedly mounted on the rotating shaft 4; the diameter of the through hole 1b of the clamp body and the through hole in the middle of the pressing plate are the same, and the shaft diameter of the rotating shaft 4 matches the clearance between the above two through holes to ensure the flexible rotation of the pressing plate 2 after assembly for easy disassembly of the workpiece; a groove 2-1 is provided on the left side of the pressing plate, and a spring 3 is installed in the groove. During assembly, the spring 3 is placed in the groove of the pressing plate, and the pressing plate is placed in the open groove on the side of the clamp body; the rotating shaft 4 passes through the through hole 1b of the clamp body and the through hole in the middle of the pressing plate, and the rotating shaft 3 is fastened to the pressing plate 2 using a second top screw 5, and the screw 6 is screwed into the threaded through hole of the pressing plate. The above components constitute a clamping mechanism using the principle of leverage: the rotating shaft 3 serves as a fulcrum, and the pressing plate 2 serves as a lever. When the screw 6 is tightened, the length of the screw screwed into the pressing plate and the clamp body increases, and the pressing plate 1a faces downward to clamp the needle valve, and at the same time, the spring 3 is compressed and stored; when the second top screw 5 is loosened, the length of the screw screwed into the pressing plate and the clamp body decreases, and the pressing plate 2a rotates to loosen the needle valve, and at the same time, the spring opens the supporting force to reset the pressing plate.

[0028] A stopper 7 is installed on the side surface of the clamp body through a fastener to limit the axial positioning of the needle valve.

[0029] On the opposite side of the stopper, a dividing plate 9 is fixedly installed on the needle valve, and a pin hole is provided below the arc-shaped positioning groove 1a of the clamp body for installing the positioning pin 8; the positioning pin 8 is inserted into the opening groove of the dividing plate 9, and a first top screw 10 is installed on the dividing plate 9 to fasten the dividing plate 9 and the needle valve together; a through hole 9d is provided in the center of the dividing plate 9 to install the non-machined outer circle d of the needle valve, and three evenly distributed opening grooves 9a, 9b, and 9c are provided around it for dividing the three evenly distributed flat planes 11a, 11b, and 11c of the needle valve 11; the first top screw 10 is installed on the dividing plate 9 to fasten the dividing plate 9 and the needle valve together. The above components constitute the indexing mechanism of the needle valve three-flat grinding tool; the locating pin 8 and the arc-shaped locating groove 1a ensure good symmetry to avoid interference between the indexing plate opening groove and the locating pin after the needle valve is inserted into the arc-shaped locating groove 1a during the second and third clamping of the needle valve during three-flat grinding; the opening sizes of the indexing plate opening grooves 9a, 9b, and 9c are matched with the size clearance of the locating pin 8 to ensure the consistency of the angles of the three flat positions of the needle valve.

[0030] The specific implementation method is to adsorb the lower end surface of the needle valve flattening tooling onto the slide of the surface grinder, take the needle valve 11 from the material tray, put the non-machined outer circle 11a of the needle valve into the center of the indexing plate 9, tighten the first top screw 10 to fasten the indexing plate 9 to the non-machined outer circle a of the needle valve, insert the outer circle 11b of the needle valve to be machined into the arc-shaped opening groove 1a of the clamp body, and at the same time, insert the indexing plate opening groove 9a on the positioning pin 8, tighten the screw 6 to pry the pressure plate 2 to press the outer circle 11b of the needle valve, and use the grinding wheel to grind the first flat plane 11c of the needle valve; then loosen the screw 6, and the pressure plate 2 is on the spring 3. Reset under the action, take the needle valve out of the arc-shaped opening groove 1a of the clamp body, and at the same time, the opening groove 9a of the dividing plate is separated from the positioning pin 8, rotate the needle valve to re-insert the outer circle 11b of the needle valve into the arc-shaped opening groove 1a of the clamp body, and at the same time, insert the opening groove 9b of the dividing plate on the positioning pin 8, repeat the above operation to clamp the needle valve, and use a grinding wheel to grind out the second flat plane 11d of the needle valve; then repeat the operation to grind out the third flat plane 11e of the needle valve, that is, use this tooling to complete the processing of the three flat planes of the needle valve; there is no need to repeatedly adjust the positioning tooling, the operation is simple, and the human influence factors are small.

[0031] In the actual implementation of the present application, a method for processing such as Figure 8The processing method for processing three step flats on the outer circle of a needle valve is shown. On the basis of the above-mentioned implementation method, after using a grinding wheel to grind the first flat plane 12a of the needle valve, do not disassemble the needle valve. The grinding wheel is re-aligned and ground to produce the step flat 12b, and then the needle valve is disassembled. The above-mentioned implementation method is repeated to complete the processing of the remaining step flats. The flat position tooling in the above-mentioned implementation case processes one needle valve at a time. In order to improve the processing efficiency, the present application can realize a three-flat grinding tooling that can clamp multiple needle valves at a time.

[0032] The above implementation scheme, on the one hand, the three-flat grinding tooling design is simple in structure, easy to manufacture at low cost, easy to operate, and does not require repeated debugging of the tooling positioning, which improves the processing accuracy and consistency. On the other hand, the developed processing method of using a surface grinder to process the three flat positions of the needle valve not only solves the problem that the flat milling process cannot meet the flat position roughness, but also effectively avoids the problem of over-tolerance and burrs caused by flat milling; it ensures the processing quality of parts, does not require tedious manual deburring processes, and reduces processing costs.

[0033] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A needle valve flat position processing tool, characterized by: The invention comprises a clamp body (1), wherein the upper end of the clamp body is provided with an arc-shaped positioning groove (1a) for positioning the needle valve and exposing the top plane of the needle valve; the clamp body is provided with two axial holes (1b), and a rotating shaft (4) is installed in the two axial holes (1b); the clamp body is provided with a side opening groove (1c), and a pressure plate (2) is installed in the side opening groove, and the rotating shaft (4) is installed in the through hole in the middle of the pressure plate; the pressure plate is provided with an inclined pressing surface (2a); the pressure plate is fixedly installed on the rotating shaft (4); the left side of the pressure plate is provided with a groove (2-1), and a spring (3) is installed in the groove; a stopper (7) is installed on the side of the clamp body through a fastener, and is used to limit the axial positioning of the needle valve; On the opposite side of the stopper, a dividing plate (9) is fixedly mounted on the needle valve, and a pin hole is provided below the arc-shaped positioning groove (1a) of the clamping body for mounting a positioning pin (8); the positioning pin (8) is inserted into an opening groove of the dividing plate (9), and a first top screw (10) is installed on the dividing plate (9) for fastening the dividing plate (9) and the needle valve together.

2. The needle valve flat position processing tool according to claim 1, characterized in that: The angle between the pressing surface (2a) of the pressing plate and the vertical direction is 30°.

3. The needle valve flat position processing tool according to claim 1, characterized in that: A second top screw (5) is provided on the pressure plate at a position corresponding to the rotating shaft, and is used to fix the rotating shaft.

4. The needle valve flat position processing tool according to claim 1, characterized in that: The lower part of the pressing plate is provided with a threaded through hole for installing a screw (6), and the screw (6) is used to adjust the pressing force of the pressing plate (2).

5. The needle valve flat position processing tool according to claim 1, characterized in that: A first push thread (10) is arranged on the indexing disc along the axial direction, and the lower end of the first push thread abuts against the outer wall of the needle valve to achieve fastening of the indexing disc and the needle valve.

6. The needle valve flat position processing tool according to claim 1, characterized in that: The evenly distributed open grooves (9a, 9b, 9c) on the indexing plate are used for indexing three evenly distributed flat planes (11a, 11b, 11c) of the needle valve.

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