Rectifying blade assembly machining method and positioning device

Abstract

The invention discloses a rectifying blade assembly machining method and a positioning device, the machining method comprises a positioning step and a drilling step, and the positioning step further comprises the step of positioning the axis of a rectifying blade assembly, the step of positioning the axial position of the rectifying blade assembly, the step of positioning the rotating direction of a blade and the step of positioning the rotating direction of a rocker arm. And after the steps are completed, finally drilling holes for mounting the positioning pins in the rocker arm on the rectifying blade assembly. The positioning device designed by the invention comprises a first positioning module for positioning the outer circle of a shaft neck, a second positioning module for positioning the outer circle of a bushing, a third positioning module for positioning the theoretical section of a blade and a fourth positioning module for positioning an inner hole of an inner ball head of a rocker arm. Accurate positioning of a hole for installing a positioning pin in the rocker arm, angular positioning of the axis of the gas compressor relative to the rectifying blade and angular positioning of the rocker arm relative to the rectifying blade can be achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of aeroengine manufacturing, and in particular relates to a positioning method and a positioning fixture in the processing of rectifying blade assembly parts. Background Art

[0002] In aircraft engines, the straightening blade assembly is an important component of the compressor. Its parts structure is as follows: Figure 1 As shown in the figure, it is mainly composed of a blade with a journal (rectifier blade), a bushing and a rocker arm to form an assembly. After the rectifier blade is assembled, the main processing object is to process a hole for installing a positioning pin on the rocker arm. After processing, it is necessary to ensure that on the VI-VI section of the rectifier blade profile, the angle between the line W of the intersection points N and K of the blade basin curve in the VI-VI section and the compressor axis is offset by a theoretical value in the positive and negative directions of the X-axis in the blade profile section coordinate system. The compressor axis is determined by a theoretical angle α deflected relative to the X-axis in the blade profile section coordinate system. However, since the coordinates of the intersection points N and K are based on the theoretical blade profile section coordinate system when the blade is modeled, they cannot be directly determined on the actual blade, that is, the theoretical intersection points N and K cannot be accurately captured on the actual blade. Therefore, it is difficult to ensure the angular position of the rocker arm and the blade by locating the two points N and K on the blade profile surface, and this problem must be solved by other positioning methods. Summary of the invention

[0003] The present invention aims to provide a straightening blade assembly processing method and positioning device, so as to realize accurate positioning of the hole for installing the positioning pin on the rocker arm and angular positioning of the compressor axis relative to the straightening blade, thereby completing the processing of the hole for installing the positioning pin.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] A method for processing a rectifying blade assembly includes a positioning step and a drilling step. The rectifying blade assembly mainly consists of a blade with a journal, a bushing, and a rocker arm with an inner ball head. A section on the blade has an angular requirement with respect to the compressor axis. The end surface of the bushing is used as a reference surface for determining the position of the section on the blade. The positioning step includes:

[0006] The step of locating the axis of the straightening blade assembly, wherein the axis of the straightening blade assembly is determined by the supporting points of the outer circle of the journal and the outer circle of the bushing in the straightening blade assembly;

[0007] The step of positioning the axial position of the straightening blade assembly, wherein the axial position of the straightening blade assembly is limited by positioning the end surface of the bushing in the straightening blade assembly;

[0008] The step of positioning the rotation direction of the blade comprises selecting a section on the blade of the rectifying blade assembly that has an angular requirement with respect to the compressor axis, and selecting a point on the blade profile curve of the section as a control point to achieve the limitation of the rotation direction of the blade around the axis of the rectifying blade assembly;

[0009] The step of positioning the rotation direction of the rocker arm is to set a control point in the inner hole of the ball head of the rocker arm to achieve the limitation of the rotation direction of the rocker arm around the axis of the rectifying blade assembly.

[0010] As an option, in the step of locating the rotation direction of the blade, the coordinate point data of the theoretical section of the blade corresponding to the section with an angular requirement to the compressor axis is obtained, and a blade profile curve is drawn according to the coordinate point data. A coordinate value is selected on the Y axis of the blade theoretical section coordinate system and a straight line parallel to the X axis of the coordinate system is drawn to intersect the blade profile curve at a point to obtain the X-axis coordinate value of the point. A line segment is obtained by connecting the point with the zero point of the blade theoretical section coordinate system, and an angle θ between the line segment and the X axis is obtained. The point is taken as a control point on the blade profile curve.

[0011] As an option, in the step of positioning the rotation direction of the rocker arm, a pin inserted into the inner hole of the ball head in the rocker arm is used as a control point to limit the rotation direction of the rocker arm around the axis of the straightening blade assembly.

[0012] Furthermore, the drilling step is to drill a hole for a locating pin on the surface of the rocker arm after completing the positioning step, wherein the axis of the hole intersects perpendicularly with the axis of the rectifying blade assembly.

[0013] A positioning device for the above-mentioned straightening blade assembly processing method comprises:

[0014] A first positioning module for positioning the outer circumference of the journal, the first positioning module comprising a first positioning groove with an upward opening and capable of accommodating the outer circumference of the journal;

[0015] A second positioning module for positioning the outer circumference of the bushing, wherein the second positioning module comprises a second positioning groove with an upward opening and capable of accommodating the outer circumference of the bushing;

[0016] A third positioning module for positioning a section on the blade that has an angular requirement with respect to the compressor axis, the third positioning module being arranged between the first positioning module and the second positioning module and comprising a ball head support and a floating support arranged coaxially, a clamping space for the section on the blade that has an angular requirement with respect to the compressor axis being formed between the ball head support and the floating support, and a contact point between the ball head support or the floating support and the blade being a control point;

[0017] A fourth positioning module for positioning the inner hole of the ball head in the rocker arm. The fourth positioning module is located on the same side of the first positioning module, the second positioning module and the third positioning module, and includes a support with an open groove for accommodating the rocker arm and a horizontal groove for placing a pin. After the pin passes through the inner hole of the ball head in the rocker arm, both ends are respectively placed in the horizontal grooves.

[0018] As an option, the lower ends of the first positioning module, the second positioning module, the third positioning module and the fourth positioning module can be detachably connected to the upper end of the base.

[0019] As an option, the size of the first positioning groove is consistent with the outer circumferential surface of the journal, and the size of the second positioning groove is consistent with the outer circumferential surface of the bushing.

[0020] Compared with the prior art, the present invention is easy to implement and has accurate positioning. It converts two difficult-to-capture points on the blade profile into one control point. In combination with other positioning measures, it can meet the correct processing of the hole for the locating pin on the rocker arm, and can accurately locate the angular relationship between the rocker arm and the blade, ultimately meeting the angular relationship between the compressor axis and the connecting line on the blade profile section that meets the processing requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is the parts diagram of the rectifying blade assembly;

[0022] Figure 2 It is a three-dimensional stereogram of the rectifying blade assembly;

[0023] Figure 3 Select the schematic diagram for the blade control points;

[0024] Figure 4 This is a diagram of the positioning device;

[0025] Figure 5 are plan and cross-sectional views of the positioning device;

[0026] Figure 6 A state diagram of clamping the rectifier blade assembly for the positioning device;

[0027] Figure 7 is a relationship diagram between the positioning device coordinate system and the rectifying blade coordinate system;

[0028] In the figure, 1-first positioning module, 2-third positioning module, 3-second positioning module, 4-fourth positioning module, 5-base. DETAILED DESCRIPTION

[0029] The present invention is further described below in conjunction with specific embodiments, but it should not be understood that the scope of the subject matter described in the present invention is limited to the following embodiments. Without departing from the above-mentioned technical ideas of the present invention, various modifications, substitutions and changes made according to common technical knowledge and customary means in the field are included in the scope of the present invention.

[0030] like Figure 1 As shown, the BB section is a section perpendicular to the line connecting the center point of the rocker arm and the center point of the blade (i.e., 90°), and the angle between the compressor axis and the X-axis in the blade profile section is α. The drawing requires that the angle between the straight line W and the line connecting the center point of the rocker arm and the center point of the blade be β, where the center point of the rocker arm and the center point of the blade can be directly found and determined on the actual rectifier blade. At this time, the position of the rocker arm is determined, and the blade has only one degree of freedom to rotate around the center point of the blade. Therefore, only one control point needs to be set on the blade to determine the position of the blade section, and then determine the position of the blade, and finally ensure the position relationship between the blade and the rocker arm (i.e., angle β), while ensuring the position relationship between the compressor axis and the straight line W on the blade basin line.

[0031] Based on the above analysis, the positioning principle of the positioning device in this embodiment is: through the straightening blade journal and the outer circle of the bushing (such as Figure 2 ) Two supporting points determine the axis of the straightening blade, and the axial position is limited by positioning the reference plane of the blade section (i.e., the bushing end face) that has an angular requirement with the compressor axis in the straightening blade drawing ( Figure 1 and Figure 3 The section with the end face length Z of the mid-distance bushing is the blade section with an angular requirement to the compressor axis as required by the parts drawing). By setting a control point on the blade section with an angular requirement to the compressor axis, the rotation direction of the blade around the axis is limited. By setting a control point in the inner hole of the ball head in the rocker arm, the rotation direction of the rocker arm around the axis is limited, and finally complete positioning is achieved.

[0032] The method for obtaining the control points on the blade section that have an angular requirement with the compressor axis is as follows: Figure 3 , the corresponding section of the blade given by the rectifier blade drawing ( Figure 3 The blade profile curve is drawn at the coordinate point of the middle section AA (the distance from the end face of the bushing is Z). Based on the blade theoretical section coordinate system where the section is located, a coordinate value on the Y axis is selected, and a straight line parallel to the X axis of the coordinate system is made to intersect the blade profile curve at a point to obtain the X axis coordinate value of the point. A line segment is obtained by connecting the point with the zero point of the blade theoretical section coordinate system, and the angle θ between the line segment and the X axis is obtained. The point is taken as the control point on the blade profile curve.

[0033] Based on the above positioning principle, the present invention is designed Figures 4 to 6The positioning device shown includes a first positioning module 1, a second positioning module 3, a third positioning module 2, a fourth positioning module 4 and a base 5, wherein:

[0034] The first positioning module 1 for positioning the outer circumference of the journal comprises a first positioning groove with an opening facing upward and capable of accommodating the outer circumference of the journal;

[0035] The second positioning module 3 for positioning the outer circumference of the bushing comprises a second positioning groove with an opening facing upward and capable of accommodating the outer circumference of the bushing;

[0036] The third positioning module 2 for positioning the section on the blade that has an angular requirement with respect to the compressor axis is arranged between the first positioning module 1 and the second positioning module 3, and includes a ball head support and a floating support arranged coaxially, and a clamping space for the section on the blade that has an angular requirement with respect to the compressor axis is formed between the ball head support and the floating support. In this embodiment, the contact point between the floating support and the blade is a control point;

[0037] The fourth positioning module 4 for positioning the inner hole of the ball head in the rocker arm is located on the same side of the first positioning module 1, the second positioning module 3 and the third positioning module 2, and comprises a support, an opening groove for accommodating the rocker arm and a horizontal groove for placing the latch, and the two ends of the latch are respectively placed in the horizontal groove after passing through the inner hole of the ball head in the rocker arm, such as Figure 5 The BB cross-section, the open groove is located between the two support plates that constitute the support, each support plate has a horizontal groove in the horizontal direction of the surface, the open groove is used to place the rocker arm (with the inner ball head part), the pin passes through the inner ball head, and the two ends of the pin are respectively placed in the horizontal grooves.

[0038] like Figure 7 , the figure shows how to apply the above method of obtaining control points to the process of positioning device design. Combined with the positioning principle of the above positioning device, it can be seen that the center point of the rocker arm and the center point of the blade (that is, the intersection of the blade axis and the blade cross section where the control point is located) have been determined. At this time, a limiting structure needs to be designed on the positioning device to limit the rotation direction of the blade around the axis of the rectifying blade assembly. Figure 7 It is assumed that the coordinate system X'O'Y' is the coordinate system of the positioning device, combined with Figure 3 The process of obtaining the control point in the blade theoretical section coordinate system is to first select a point on the Y' axis in the coordinate system X'O'Y', and draw a straight line parallel to the X' axis through the point and intersect the blade profile curve of the blade theoretical section at a point. This point is used as the control point, that is, Figure 5The contact point between the floating support and the blade on the central positioning device connects the control point and the O' point of the coordinate system X'O'Y' to obtain a straight line with an angle θ' with the X' axis. This straight line is the basis for the design of the slot position, size, and ball head support and floating support position of the third positioning module 2 (that is, the coordinate value and angle θ' of the control point on the blade profile curve are obtained by drawing and measuring, thereby designing the third positioning module 2).

[0039] The three-dimensional schematic diagram of the positioning device is as follows Figure 4 , through the journal and bushing outer circle in the rectifying blade assembly (such as Figure 2 ) two supporting points determine the axis of the rectifying blade assembly, which is achieved by setting the first positioning module 1 and the second positioning module 3 on the front and rear of the base 5 respectively. The main structural feature of the first positioning module 1 and the second positioning module 3 is that each of the upper ends has an open slot as a positioning slot (the opening faces upward), and the width of the open slot is consistent with the corresponding journal and bushing outer circle size. The main consideration for adopting the open slot structure is to facilitate the placement of parts. The blade is limited in the direction of rotation around the axis by setting a control point on the theoretical cross section of the blade, which is achieved by Figure 5 As shown in the AA view, a slot is opened in the middle of the third positioning module 2 to form a space for accommodating the blades. A fixed ball head support is arranged in the upper part of the slot, and the contact point between the ball head support and the blade is determined by the coordinates of the control point on the blade profile curve obtained when designing the above-mentioned positioning device and the axis of the floating support. A floating support with adjustable height is arranged in the lower part of the slot. The floating support is realized by the cooperation of the ball head screw and the threaded hole on the third positioning module 2. The screw is turned to adjust the floating support up and down, thereby ensuring reliable positioning of the blade profile and the support point. A control point is set by the inner hole of the ball head in the rocker arm to realize the limitation of the rotation direction of the rocker arm around the axis, and the implementation method is as follows: Figure 5 As shown in the middle BB view, the vertical limit is achieved by the combination of the pin, the horizontal notch on the support and the inner hole of the ball head in the rocker arm. The horizontal notch on the support is an open straight groove, which only plays a role in the vertical limit, and does not limit the horizontal position, thus avoiding the problem of over-positioning. The final clamping state of the rectifier blade assembly on the positioning device is shown in the figure. Figure 6 shown.

[0040] The contents not described in detail in the specification of the present invention belong to the prior art known to the professional and technical personnel in the field. Although the illustrative specific embodiments of the present invention are described above to facilitate the understanding of the present invention by the technical personnel in the field, it should be clear that the present invention is not limited to the scope of the specific embodiments. For ordinary technicians in the field of this technology, as long as various changes are within the spirit and scope of the present invention defined and determined by the attached claims, these changes are obvious, and all inventions and creations using the concept of the present invention are protected.

Claims

1. A method for processing a straightening blade assembly, comprising a positioning step and a drilling step, wherein the straightening blade assembly is mainly composed of a blade with a journal, a bushing and a rocker arm with an inner ball head, wherein a section on the blade has an angular requirement with respect to the compressor axis, and an end surface of the bushing is used as a reference surface for determining the position of the section on the blade, wherein the straightening blade assembly is mainly composed of a blade with a journal, a bushing and a rocker arm with an inner ball head, wherein a section on the blade has an angular requirement with respect to the compressor axis, and an end surface of the bushing is used as a reference surface for determining the position of the section on the blade, wherein the straightening blade assembly is mainly composed of a blade with a journal, a bushing and a rocker arm with an inner ball head, and wherein the blade has a section with an angular requirement with respect to the compressor axis, and the end surface of the bushing is used as a reference surface for determining the position of the section on the blade, and wherein the straightening blade assembly is mainly composed of a blade with a journal, a bushing and a rocker arm with an inner ball head, and wherein the blade has a section with an angular requirement with respect to the compressor axis, and wherein ... The positioning steps include: The step of locating the axis of the straightening blade assembly, wherein the axis of the straightening blade assembly is determined by the supporting points of the outer circle of the journal and the outer circle of the bushing in the straightening blade assembly; The step of positioning the axial position of the straightening blade assembly, wherein the axial position of the straightening blade assembly is limited by positioning the end surface of the bushing in the straightening blade assembly; The step of positioning the rotation direction of the blade comprises selecting a section on the blade of the rectifying blade assembly that has an angular requirement with respect to the compressor axis, and selecting a point on the blade profile curve of the section as a control point to achieve the limitation of the rotation direction of the blade around the axis of the rectifying blade assembly; The step of positioning the rotation direction of the rocker arm is to set a control point in the inner hole of the ball head of the rocker arm to achieve the limitation of the rotation direction of the rocker arm around the axis of the rectifying blade assembly.

2. A method for processing a rectifying blade assembly according to claim 1, characterized in that: In the step of locating the rotation direction of the blade, the coordinate point data of the theoretical section of the blade corresponding to the section with angular requirements to the compressor axis are obtained, and a blade profile curve is drawn according to the coordinate point data. A coordinate value is selected on the Y axis of the blade theoretical section coordinate system and a straight line parallel to the X axis of the coordinate system is drawn to intersect the blade profile curve at a point to obtain the X axis coordinate value of the point, and a line segment is obtained by connecting the point with the zero point of the blade theoretical section coordinate system, and the angle θ between the line segment and the X axis is obtained, and the point is taken as the control point on the blade profile curve.

3. A method for processing a rectifying blade assembly according to claim 1, characterized in that: In the step of positioning the rotation direction of the rocker arm, a pin inserted into the inner hole of the ball head in the rocker arm is used as a control point to limit the rotation direction of the rocker arm around the axis of the rectifying blade assembly.

4. A method for processing a rectifying blade assembly according to claim 1, characterized in that: The drilling step is as follows: after completing the positioning step, a hole for a positioning pin is drilled on the surface of the rocker arm, and the axis of the hole intersects perpendicularly with the axis of the rectifying blade assembly.

5. A positioning device used in the processing method of the straightening blade assembly according to claim 1, characterized in that: include: A first positioning module (1) for positioning the outer circumference of a journal, the first positioning module (1) comprising a first positioning groove with an upward opening and capable of accommodating the outer circumference of the journal; A second positioning module (3) for positioning the outer circumference of the bushing, the second positioning module (3) comprising a second positioning groove with an upward opening and capable of accommodating the outer circumferential surface of the bushing; A third positioning module (2) for positioning a section on a blade that has an angular requirement with respect to the compressor axis, the third positioning module (2) being arranged between the first positioning module (1) and the second positioning module (3), and comprising a ball head support and a floating support arranged coaxially, a clamping space for the section on the blade that has an angular requirement with respect to the compressor axis being formed between the ball head support and the floating support, and a contact point between the ball head support or the floating support and the blade being a control point; A fourth positioning module (4) for positioning the inner hole of the ball head in the rocker arm, the fourth positioning module (4) being located on the same side of the first positioning module (1), the second positioning module (3) and the third positioning module (2), and comprising a support, an open groove on the support for accommodating the rocker arm and a horizontal groove for placing a latch, and the latch passes through the inner hole of the ball head in the rocker arm, and the two ends of the latch are respectively placed in the horizontal grooves.

6. The positioning device according to claim 5, characterized in that: The lower ends of the first positioning module (1), the second positioning module (3), the third positioning module (2) and the fourth positioning module (4) can all be detachably connected to the upper end of the base (5).

7. The positioning device according to claim 5, characterized in that: The size of the first positioning groove is consistent with the outer circumferential surface of the journal, and the size of the second positioning groove is consistent with the outer circumferential surface of the bushing.

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