A high-precision fuel injector shell rotating extension device

Abstract

The application discloses a high-precision fuel injector shell rotating extension device, which comprises a workpiece clamp assembly fixed on a machine table, a clamping assembly and a rotating lifting assembly connected below the workpiece clamp assembly, and a pressing assembly movably arranged above the workpiece clamp assembly. Through precise mechanical design, a spiral line is formed on the surface of the cylindrical metal, and the length of the cylindrical metal is adjusted by micrometers by changing the length and depth of the spiral line. The application makes the fuel injector valve needle stroke adjustment more accurate, controllable and efficient.

Description

TECHNICAL FIELD

[0001] The application relates to a high-precision rotating extension device for an oil injector shell and belongs to the technical field of automatic equipment. BACKGROUND

[0002] The oil injector is a core component of a fuel vehicle engine, and the core function of the oil injector is to generate a magnetic force by an electromagnet in the oil injector after the energization of an electromagnetic coil, drive a valve needle to open and close, and realize the function of oil injection. The opening and closing stroke of the valve needle determines the oil injection amount of the oil injector, so the stroke must be accurately controlled and manufactured. The length of the oil injector shell can be controlled to accurately control the opening and closing stroke of the valve needle inside.

[0003] The existing implementation mode of the technology is to use a high-precision servo press to clamp a cylindrical thin-wall metal shell of an oil injector and directly perform axial lifting, and the deformation amount of the oil injector shell is controlled through a precise displacement measurement system inside the servo press.

[0004] The servo press system clamping and lifting system has the following disadvantages: 1. The precision of the servo press cannot meet the design requirements. The opening and closing stroke of the valve needle is 50+5 microns, and the precision of the ordinary servo press is only 3 microns, which cannot meet the tolerance of 10%, that is, within 1 micron. 2. The lifting mode can cause metal rebound. Since the inside of the oil injector is relatively complex, the rebound size is difficult to control. SUMMARY

[0005] The application aims to solve the technical problem of providing a high-precision rotating extension device for an oil injector shell. Through precise mechanical design, a lifting spiral line is formed on the surface of the cylindrical metal, and the length of the cylindrical metal is adjusted by microns by changing the length and depth of the spiral line. The application of the application makes the oil injector valve needle stroke adjustment more accurate, more controllable and more efficient.

[0006] In order to solve the above technical problems, the technical scheme adopted by the application is:

[0007] A high-precision rotating extension device for an oil injector shell comprises a workpiece clamp assembly fixed on a machine table, a clamping assembly and a rotating lifting assembly connected below the workpiece clamp assembly, and a pressing assembly movably arranged above the workpiece clamp assembly, wherein

[0008] The clamping assembly comprises a follow-up bearing and a hob assembly movably arranged for clamping the oil injector shell.

[0009] The rotating and lifting assembly comprises a mechanism rotating shaft fixedly connected with the clamping assembly, a planetary roller screw fixedly connected with the lower end of the mechanism rotating shaft, a screw nut assembly cooperatively used with the lower end of the planetary roller screw, a connecting rod shaft driven by a servo motor arranged on one side of the planetary roller screw, a first synchronous pulley and a second synchronous pulley respectively arranged on the upper end and the lower end of the connecting rod shaft, a third synchronous pulley connected with the first synchronous pulley arranged on the screw nut assembly, a fourth synchronous pulley connected with the second synchronous pulley arranged on the mechanism rotating shaft, and the screw nut is limited in the axial position and can be rotated by the third synchronous pulley in the horizontal plane.

[0010] The high-precision fuel injector shell rotating and extending device has the characteristics that the pressing assembly comprises a movable pressing plate, the center of the pressing plate is provided with an opening for inserting the clamped fuel injector shell, and a pressure sensor and a displacement sensor are arranged in the opening.

[0011] The high-precision fuel injector shell rotating and extending device has the characteristics that spring guide columns are arranged at the four corners of the pressing plate.

[0012] The high-precision fuel injector shell rotating and extending device has the characteristics that the follow-up bearing and the hob assembly are driven and clamped by two air cylinders, and the number of the follow-up bearings is two and the follow-up bearings are distributed in a triangular shape with the hob assembly.

[0013] The high-precision fuel injector shell rotating and extending device has the characteristics that the workpiece clamp assembly comprises a support plate, and the support plate is provided with a through hole for inserting the lower end of the fuel injector shell.

[0014] The high-precision fuel injector shell rotating and extending device has the characteristics that the first synchronous pulley is a seventeen-tooth synchronous pulley, the second synchronous pulley is a twenty-tooth synchronous pulley, the third synchronous pulley and the fourth synchronous pulley are sixty-tooth synchronous pulleys, and the lead of the planetary roller screw is 1 mm.

[0015] The high-precision fuel injector shell rotating and extending device has the characteristics that the high-precision planetary roller screw and the synchronous pulley transmission tooth difference are used to press a spiral line with a lead of 0.15 mm on the shell, the shell is extruded at the spiral line and extends downward, the shell is elongated by 1 micrometer per 360 degrees of spiral line, the number of spiral lines is controlled to achieve the purpose of accurately controlling the length of the shell, and the spiral line is permanently pressed on the shell, so the problem of springback does not need to be considered. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1It is the front view of a high-precision fuel injector shell rotating extension device of the present application;

[0017] Figure 2 It is the side view of a high-precision fuel injector shell rotating extension device of the present application;

[0018] Figure 3 It is Figure 2 The enlarged schematic view of C in the middle;

[0019] Figure 4 It is Figure 2 The B-B sectional view in the middle;

[0020] Figure 5 It is Figure 4 The enlarged schematic view of D in the middle;

[0021] Figure 6 It is the front view of a rotating assembly of a high-precision fuel injector shell rotating extension device of the present application;

[0022] Figure 7 It is the side view of a rotating assembly of a high-precision fuel injector shell rotating extension device of the present application;

[0023] Figure 8 It is Figure 7 The A-A sectional view in the middle;

[0024] Figure 9 It is the schematic view of a clamp and clamping assembly connection of a high-precision fuel injector shell rotating extension device of the present application;

[0025] Figure 10 It is the structural schematic view of a clamping assembly of a high-precision fuel injector shell rotating extension device of the present application. DETAILED DESCRIPTION

[0026] The present application will be further described below in conjunction with the accompanying drawings.

[0027] As Figures 1-10As shown, a high-precision fuel injector shell rotating extension device includes a workpiece clamp assembly 10 fixed on a machine table, a clamping assembly 20 and a rotating lifting assembly 30 connected below the workpiece clamp assembly 10, and a pressing assembly 40 movably arranged above the workpiece clamp assembly 10, wherein the clamping assembly 20 includes movable follow-up bearings 22 and a hob assembly 23 for clamping a fuel injector shell 50; the rotating lifting assembly 30 includes a mechanism rotating shaft 37 fixedly connected with the clamping assembly 20, a planetary roller screw 38 fixedly connected with a lower end of the mechanism rotating shaft 37, a screw nut assembly cooperatively used with a lower end of the planetary roller screw 38, a connecting rod shaft 32 driven by a servo motor 31 arranged on one side of the planetary roller screw 38, a first synchronous pulley 33 and a second synchronous pulley 34 arranged at upper and lower ends of the connecting rod shaft 32 respectively, a third synchronous pulley 35 connected with the first synchronous pulley 33 arranged on the screw nut assembly, a fourth synchronous pulley 36 connected with the second synchronous pulley 34 arranged on the mechanism rotating shaft 37, and the screw nut is limited in axial position and can be rotated by the third synchronous pulley 35 in a horizontal plane.

[0028] In the embodiment, the workpiece clamp assembly 10 includes a support plate 11 provided with a through hole for inserting a lower end of the fuel injector shell 50, and the pressing assembly 40 includes a pressing plate 41 movably arranged above the support plate 11, the center of the pressing plate 41 is provided with an opening for inserting the fuel injector shell 50, and the opening is provided with a pressure sensor 44 and a displacement sensor 43.

[0029] After the fuel injector shell 50 to be machined is inserted into the through hole, the lower end to be machined is exposed below the support plate 11, the pressing assembly 40 is pressed down, the motor and screw rod on the pressing assembly 40 drive the pressing plate 41 to press down, the upper end of the fuel injector shell 50 is inserted into the opening, the pressure sensor 44 is used to detect the pressure applied by the pressing plate 41 to the fuel injector shell 50, until the applied pressure reaches a preset value, to ensure that the fuel injector shell 50 will not rotate during the subsequent spiral line marking process, and the four corners of the pressing plate 41 are provided with spring guide columns 42, so that the entire pressing process is a flexible pressing process, which will not damage the fuel injector shell 50.

[0030] After the fuel injector shell 50 is pressed by the pressing plate 41, the follow-up bearings 22 and the hob assembly 23 are driven by the air cylinder 21 to clamp the lower end of the fuel injector shell 50, wherein the number of the follow-up bearings 22 is two, and the follow-up bearings 22 are distributed in a triangular shape with the hob assembly 23, to ensure the clamping force of the fuel injector shell 50.

[0031] The connecting rod shaft 32 driven by the servo motor 31 rotates, thereby driving the third synchronous pulley 35 and the fourth synchronous pulley 36 to rotate by the first synchronous pulley 33 and the second synchronous pulley 34 respectively. In the embodiment, the first synchronous pulley 33 is a seventeen-tooth synchronous pulley, the second synchronous pulley 34 is a twenty-tooth synchronous pulley, the third synchronous pulley 35 and the fourth synchronous pulley 36 are sixty-tooth synchronous pulleys, and the lead of the planetary roller screw 38 is 1 mm.

[0032] Since the screw nut is only fixed by the fixed bearing in axial movement, but can still rotate, assuming that the rotating speed of the servo motor 31 is R revolutions per second, because the tooth number ratio of the second synchronous pulley 34 to the fourth synchronous pulley 36 is twenty to sixty, that is, the rotating speed of the mechanism rotating shaft 37 and the screw rod part of the planetary roller screw 38 is 20 / 60R, the tooth number ratio of the first synchronous pulley 33 to the third synchronous pulley 35 is seventeen to sixty, that is, the rotating speed of the nut part of the planetary roller screw 38 is 17 / 60R, therefore, when the mechanism rotating shaft 37 rotates 20 / 60R (one third of a circle), the nut part of the planetary roller screw 37 rotates (20 / 60R-17 / 60R)=3 / 60R relative to the screw rod part, combined with the lead of the screw rod being 1 mm, the mechanism rotating shaft 37 rotates one circle, and the axial movement is 0.15 mm, that is, the axial movement of the clamping assembly 20 is 0.15 mm, which can generate a spiral line on the surface of the oil injector shell 50 by the follow-up bearing 22 and the hobbing assembly 23. The number of turns of the spiral line is linearly related to the length of the elongation of the shell, and the spiral line is 360 degrees, and the shell is elongated by 1 micron. Therefore, the length of the cylindrical metal is adjusted by micron level by changing the length and depth of the spiral line.

[0033] In the actual processing process, the lead of the spiral line generated on the surface of the oil injector shell 50 by the follow-up bearing 22 and the hobbing assembly 23 can be adjusted by selecting synchronous pulleys with different tooth number ratios and planetary roller screws with different leads.

[0034] In the process of drawing the spiral line on the surface of the oil injector shell 50 by the follow-up bearing 22 and the hobbing assembly 23, the displacement sensor 43 can be used to detect the displacement change of the valve needle in the oil injector shell 50, so as to monitor the final valve needle stroke.

[0035] In summary, the present application provides a high-precision oil injector shell rotating extension device, which forms a spiral line on the surface of the cylindrical metal by precise mechanical design, and adjusts the length of the cylindrical metal by micron level by changing the length and depth of the spiral line. The application of the present application makes the oil injector valve needle stroke adjustment more accurate, more controllable and more efficient.

[0036] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above-mentioned embodiments, and the above-mentioned embodiments and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A high-precision fuel injector housing rotating extension device, characterized by: The utility model provides a workpiece fixture assembly (10) fixed on a machine table, a clamping assembly (20) and a rotary lifting assembly (30) are arranged below the workpiece fixture assembly (10), a pressing assembly (40) can move up and down relative to the workpiece fixture assembly (10) and is arranged above the workpiece fixture assembly (10), wherein the clamping assembly (20) comprises a follow-up bearing (22) and a hob assembly (23) for clamping an oil injector shell (50) and can move relative to each other. The rotary lifting assembly (30) comprises a mechanism rotating shaft (37) fixedly connected with the clamping assembly (20), a planetary roller screw (38) fixedly connected with the lower end of the mechanism rotating shaft (37), a screw nut assembly cooperatively used with the lower end of the planetary roller screw (38), a connecting rod shaft (32) driven by a servo motor (31) arranged on one side of the planetary roller screw (38), a first synchronous pulley (33) and a second synchronous pulley (34) arranged at the upper and lower ends of the connecting rod shaft (32) respectively, a third synchronous pulley (35) connected with the first synchronous pulley (33) arranged on the screw nut assembly, a fourth synchronous pulley (36) connected with the second synchronous pulley (34) arranged on the mechanism rotating shaft (37), and the screw nut is limited in the axial position and can be rotated by the third synchronous pulley (35) in the horizontal plane. The pressing assembly (40) comprises a pressing plate (41) that can move up and down, the center of the pressing plate (41) is provided with an opening for inserting the clamping oil injector shell (50), and a pressure sensor (44) and a displacement sensor (43) are arranged in the opening. The follow-up bearing (22) and the hob assembly (23) are driven and clamped by two air cylinders (21) and the oil injector shell (50), the number of the follow-up bearings (22) is two, and the follow-up bearings (22) are distributed in a triangular shape with the hob assembly (23). The first synchronous pulley (33) is a seventeen-tooth synchronous pulley, the second synchronous pulley (34) is a twenty-tooth synchronous pulley, the third synchronous pulley (35) and the fourth synchronous pulley (36) are sixty-tooth synchronous pulleys, and the lead of the planetary roller screw (38) is 1mm.

2. The high-precision fuel injector housing rotating and extending device according to claim 1, characterized in that: Spring guide columns (42) are arranged at the four corners of the pressing plate (41).

3. The high-precision fuel injector housing rotating and extending device according to claim 1, characterized in that: The workpiece fixture assembly (10) comprises a support plate (11), and the support plate (11) is provided with a through hole for inserting the lower end of the oil injector shell (50).

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