Fixture device for flexible machining of precision hole of aircraft titanium alloy butt joint

Abstract

The utility model provides a clamp device for flexibly machining a precision hole of an aircraft titanium alloy butt joint. The clamp device comprises a clamp body (1), a main positioning hole base (2), an auxiliary positioning hole base (3), a bridge plate (4), a bridge plate fixing supporting column (5), a bridge plate fastening piece (6), a main positioning pin and an auxiliary positioning pin (10). The main positioning hole base (2), the auxiliary positioning hole base (3) and the bridge plate fixing supporting column (5) are installed on the clamp body (1), the auxiliary positioning hole base (3) can be flexibly and movably adjusted along a U-shaped groove in the clamp body (1), the bridge plate (4) is fixed to the bridge plate fixing supporting column (5) through the bridge plate fastening piece (6), two positioning holes are formed in the bridge plate (4), and one positioning hole is a kidney-shaped hole. Double lugs of the part are clamped on the bridge plate (4); the main positioning pin and the auxiliary positioning pin (10) with the same maximum end diameter are selected according to the aperture of the main positioning hole before machining, the aperture of the main positioning hole after machining and the aperture of the auxiliary positioning hole before machining in the part. The fixture is simple, convenient and economical, and can achieve the purposes of convenience in clamping and alignment, small clamping error, high processing efficiency and high product quality.

Description

Technical Field

[0001] This utility model relates to the field of machining high-precision parts for key connection parts in the aerospace industry, specifically to a fixture device for flexible machining of precision holes in aircraft titanium alloy butt joints. Background Technology

[0002] With the rapid development of aviation technology, parts are becoming more complex and integrated. A titanium alloy composite double-ear four-hole butt joint is increasingly used as the main load-bearing component for connecting key moving parts of the aircraft. To ensure strength and weight, the part is generally made of titanium alloy forgings that are more difficult to machine, and the raw material is expensive. At the same time, the precision holes on the double ears are particularly important because they connect various moving parts of the aircraft.

[0003] Based on the specific processing technology analysis of titanium alloy composite double-ear four-hole butt joint parts, the complex structure derived from the integrated design of such parts leads to high difficulty in processing and easy quality problems. Furthermore, due to the aircraft layout design, there are many similar structural parts, resulting in low processing efficiency and high labor intensity for workers. Therefore, it is of great significance to explore a high-precision, high-quality, and high-efficiency processing method for the holes on the parts. Utility Model Content

[0004] This utility model provides a fixture device for flexible machining of precision holes in aircraft titanium alloy butt joints. It is simple and economical, and can achieve the goals of convenient clamping and alignment, small clamping error, high machining efficiency and high product quality.

[0005] This utility model provides a fixture device for flexible machining of precision holes in aircraft titanium alloy docking joints, including: fixture body 1, main positioning hole base 2, auxiliary positioning hole base 3, bridge plate 4, bridge plate fixing support 5, bridge plate fastener 6, main positioning pin, and auxiliary positioning pin 10.

[0006] The main positioning hole base 2, the auxiliary positioning hole base 3 and the bridge plate fixing support 5 are installed on the fixture body 1. The auxiliary positioning hole base 3 can be flexibly adjusted along the U-shaped groove on the fixture body 1. The bridge plate 4 is fixed on the bridge plate fixing support 5 by the bridge plate fastener 6. The bridge plate 4 is provided with two positioning holes, one of which is a waist-shaped hole.

[0007] The main positioning hole base 2 and the auxiliary positioning hole base 3 are located below the bridge plate 4 and correspond to the two positioning holes on the bridge plate 4. The auxiliary positioning hole base 3 also corresponds to the waist-shaped hole.

[0008] The two lugs of the part are mounted on bridge plate 4;

[0009] When machining the first hole of the part, the auxiliary positioning pin 10 passes through the auxiliary positioning hole of the part and the positioning hole of the bridge plate 4 and is inserted into the auxiliary positioning hole base 3 to machine the main positioning hole; when machining the second hole, the auxiliary positioning pin 10 is removed and the main positioning pin passes through the main positioning hole of the part and the positioning hole of the bridge plate 4 and is inserted into the main positioning hole base 2 to machine the auxiliary positioning hole.

[0010] There are multiple main positioning pins and auxiliary positioning pins 10, all of which are stepped pins. The diameter of the smallest end is the same as the inner diameter of the main positioning hole base 2 and the auxiliary positioning hole base 3, and the diameter of the middle section is the same as the positioning hole diameter of the bridge plate 4.

[0011] Select main locating pins and auxiliary locating pins 10 with the same maximum end diameter based on the diameter of the main locating hole before machining, the main locating hole after machining, and the auxiliary locating hole before machining on the part.

[0012] Optionally, the fixture device for flexibly machining precision holes of aircraft titanium alloy docking joints also includes: lug pressure plate 11 and jack and attached pressure plate 12.

[0013] Before machining the positioning holes on the part, and when the main positioning pin and the auxiliary positioning pin 10 are both inserted into the main positioning hole base 2 and the auxiliary positioning hole base 3, the ear plate pressure plate 11 and the jack and the attached pressure plate 12 are respectively set at the ear end of the part and the end away from the ear.

[0014] Optionally, the distance between the auxiliary positioning hole base 3 and the main positioning hole base 2 can be adjusted according to the distance between the holes on the part.

[0015] Optionally, the perpendicularity of the positioning hole axis to the top surface of bridge plate 4 is within 0.03mm.

[0016] Optionally, the flatness of the top surface of bridge plate 4 is within 0.02mm.

[0017] Optionally, the parallelism between the line connecting the positioning holes on the bridge plate 4 and the alignment edge of the fixture body 1 is within 0.03mm.

[0018] This invention provides a fixture device for flexible machining of precision holes in aircraft titanium alloy butt joints. It achieves a high degree of overlap between the design datum and the machining datum, reducing errors caused by datum conversion control and improving the product quality of high-precision key components. It enables rapid and high-precision clamping and positioning, eliminating the need for repeated manual adjustments and alignment, thus increasing machining efficiency and reducing workload. It allows for flexible machining of dual-ear structure parts on the same fixture, reducing the use of dedicated fixtures, providing a new approach to machining similar parts, and lowering machining costs. Attached Figure Description

[0019] Figure 1A schematic diagram of a fixture device for flexibly machining precision holes in aircraft titanium alloy butt joints;

[0020] Figure 2 A diagram illustrating the machining of parts. Figure 1 ;

[0021] Figure 3 A schematic diagram of the main and auxiliary locating pins before and after part processing;

[0022] Figure 4 A diagram illustrating the machining of parts. Figure 2 ;

[0023] Figure 5 This is a schematic diagram of the pressure plate;

[0024] Figure 6 This diagram illustrates the state of a part being clamped in a fixture and ready for machining. Figure 1 ;

[0025] Figure 7 This diagram illustrates the state of a part being clamped in a fixture and ready for machining. Figure 2 ;

[0026] Explanation of reference numerals in the attached figures:

[0027] 1. Fixture body, 2. Main positioning hole base, 3. Auxiliary positioning hole base, 4. Bridge plate, 5. Bridge plate fixing support, 6. Bridge plate fastener, 7. Workpiece, 8. Main positioning pin before machining, 9. Main positioning pin after machining, 10. Auxiliary positioning pin, 11. Ear plate pressure plate, 12. Jack and attached pressure plate. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0029] The features and illustrative embodiments of various aspects of this utility model will now be described in detail. In the following detailed description, numerous specific details are set forth in order to provide a comprehensive understanding of this utility model. However, it will be apparent to those skilled in the art that this utility model can be practiced without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of this utility model by illustrating examples of it. This utility model is by no means limited to any specific arrangements and methods set forth below, but covers any improvements, substitutions, and modifications to the structure, method, and apparatus without departing from the spirit of this utility model. In the accompanying drawings and the following description, well-known structures and techniques are not shown to avoid unnecessarily obscuring this utility model.

[0030] It should be noted that, where there is no conflict, the embodiments of this utility model and the features therein can be combined with each other, and the various embodiments can be referenced and cited in turn. The present utility model will now be described in detail with reference to the accompanying drawings and embodiments.

[0031] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the implementation of the present invention is not limited thereto.

[0032] The part material is TC21 forging. The part hole accuracy is grade 7 tolerance, roughness Ra1.6, position tolerance is Φ0.1, and the perpendicularity tolerance of the hole axis to the inner end face of the hole lug is Φ0.05. In addition, there are many such parts. In order to meet the part machining quality, it is difficult and the error is large when clamping and aligning a single part. At the same time, the clamping and alignment time is long.

[0033] The design datum for the part is the inner surface of a single-sided hole and a double-eared hole. To meet the strict tolerance control requirements of the part, the four holes with double ears are machined using a precision boring machine in a free state based on the design datum. Before machining on the precision boring machine, a CNC machining center ensures that the holes have a set allowance. The surface and thickness of the ear pieces are ensured by CNC machining. Selecting similar parts, the hole spacing and diameter differences are determined. One set of holes is used as the main positioning holes, and the other set as auxiliary positioning holes. A fixture is designed, with main and auxiliary positioning pin hole bases respectively. Fixing holes for the main positioning pin base and U-shaped grooves for the auxiliary positioning pin hole base are made on the fixture body. The auxiliary positioning pin hole base can move flexibly and freely on the fixture body along the length of the U-shaped groove. A bridge plate designed on the fixture pre-supports and positions the inner surface of the double-eared hole of the part, and then the main positioning pin passes through... Positioning is achieved through the upper lug hole, bridge plate through hole, lower lug hole, and main positioning pin hole base of the part. Positioning is achieved through the upper lug hole, bridge plate through hole, lower lug hole, and auxiliary positioning pin hole base of the part. The machining coordinates of the part boring are always based on the center of the main positioning pin hole as the origin. The alignment direction is the line connecting the main positioning and auxiliary positioning pin holes of the fixture. That is, only the direction of the line connecting the centers of the main positioning hole and the main and auxiliary positioning holes of the fixture needs to be set. After that, only clamping is required. The coordinates can be flexibly moved according to the inherent two-hole spacing of the part to achieve high-quality and high-efficiency machining of the precision holes of the part.

[0034] Specific solution steps:

[0035] 1. Analyze the structure of parts of the same family, count the hole diameter and hole spacing of the parts, and determine the maximum and minimum limit distance between the main positioning hole and the auxiliary positioning hole of the mounting fixture;

[0036] The outer diameter range of the main locating pin and the auxiliary locating pin has also been determined. Table 1 below shows the flexibly interchangeable dimensions of the main and auxiliary locating pins. Multiple parts of the same type can be assembled and analyzed.

[0037] 2. Analyze the common overlap area of ​​the inner end faces of the lugs of the same type of parts to determine the size of the positioning bridge plate;

[0038] 3. The fixture is equipped with two sets of detachable pin bases, one set for setting the main positioning hole and the other set for setting the auxiliary positioning hole that moves flexibly in one direction.

[0039] 4. Install the fixture on the boring machine, ensuring that the straightening and alignment edge on the fixture is parallel to the line connecting the centers of the two positioning holes on the base. Always use the center of the hole where the main positioning pin hole on the fixture coincides with the main positioning hole of the part as the origin of the machining coordinate system. Input the hole coordinates of the auxiliary positioning hole of the part into the boring machine control system. Using this method, input the second hole coordinates of similar parts according to the set number.

[0040] 5. Position the part in the Z direction by overlapping the bridge plate, then position it by passing the main positioning pin through the hole of the part, the bridge plate and the main positioning pin base, and finally position it by the auxiliary positioning pin. The base of the auxiliary positioning pin can move parallel along the straightening edge of the fixture to ensure flexible positioning of the part pin.

[0041] 6. After the pin is positioned, tighten the lug end of the part with a special pressure plate. After the lug is tightened, use a jack to support the other end of the part to ensure that the part is not affected by stress caused by the center of gravity offset.

[0042] 7. First, pull out the main locating pin, process the main locating pin, and after processing, insert the main locating pin, pull out the auxiliary locating pin hole, and process the auxiliary locating hole by calling the set part number coordinate.

[0043] 8. After machining, remove the part and clamp the next part directly. Repeat steps 5-7 to machine the next part.

[0044] like Figure 1-7 As shown, Figure 1 The main positioning hole base 2, auxiliary positioning hole base 3, and bridge plate fixing support 5 are installed on the fixture body 1. The bridge plate 4 is fixed to the bridge plate fixing support 5 using bridge plate fasteners 6. After the above is completed, to ensure the subsequent machining accuracy, check that the parallelism between the positioning hole connection line and the fixture alignment edge is controlled within 0.03mm, the flatness of the bridge plate top surface is controlled within 0.02mm, and the perpendicularity between the positioning hole axis and the bridge plate top surface is controlled within 0.03mm. The auxiliary positioning pin base can move freely along the alignment direction. Input the coordinate system of the holes of similar parts.

[0045] Will Figure 2 One end face of the inner side of the ear piece of part 7 rests on the clamp bridge plate, and the parts are taken to correspond to the main and auxiliary positioning pins in Table 1 below.

[0046] Table 1

[0047]

[0048] First, insert the main locating pin 8 through the part hole and the through hole of the bridge plate 4 into the main locating hole base 2 before machining. Then, insert the auxiliary locating pin 10 through the part hole and the through hole of the bridge plate 4 into the auxiliary locating hole base 3. The auxiliary locating hole base 3 can be flexibly adjusted along the U-shaped groove on the fixture body 1. After checking that both the main and auxiliary locating pins are inserted, press the part firmly with the part lug plate 11. After pressing, use a jack and the attached pressure plate 12 to provide auxiliary support for the part. After completing the above, first pull out the main locating pin 8, then insert the main locating pin 9 after machining, pull out the auxiliary locating pin 10, and machine the auxiliary locating hole. After machining, remove the part and replace it with the next part of the same type.

[0049] The above description is only a further embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the scope disclosed by the present utility model, based on the technical solution and concept of the present utility model, shall fall within the protection scope of the present utility model.

Claims

1. A fixture device for flexibly machining precision holes in aircraft titanium alloy butt joints, characterized in that, include: Fixture body (1), main positioning hole base (2), auxiliary positioning hole base (3), bridge plate (4), bridge plate fixing support (5), bridge plate fastener (6), main positioning pin, auxiliary positioning pin (10); The main positioning hole base (2), the auxiliary positioning hole base (3) and the bridge plate fixing support (5) are installed on the fixture body (1), and the auxiliary positioning hole base (3) can be flexibly adjusted along the U-shaped groove on the fixture body (1). The bridge plate (4) is fixed on the bridge plate fixing support (5) by the bridge plate fastener (6). The bridge plate (4) is provided with two positioning holes, one of which is a waist-shaped hole. The main positioning hole base (2) and the auxiliary positioning hole base (3) are located below the bridge plate (4) and correspond to the two positioning holes on the bridge plate (4), and the auxiliary positioning hole base (3) corresponds to the waist-shaped hole; The two lugs of the part are mounted on the bridge plate (4); When machining the first hole of the part, the auxiliary positioning pin (10) passes through the auxiliary positioning hole of the part and the positioning hole of the bridge plate (4) and is inserted into the auxiliary positioning hole base (3) to machine the main positioning hole; when machining the second hole, the auxiliary positioning pin (10) is removed and the main positioning pin passes through the main positioning hole of the part and the positioning hole of the bridge plate (4) and is inserted into the main positioning hole base (2) to machine the auxiliary positioning hole; There are multiple main positioning pins and auxiliary positioning pins (10), all of which are stepped pins. The diameter of the smallest end is consistent with the inner diameter of the main positioning hole base (2) and the auxiliary positioning hole base (3), and the diameter of the middle section is consistent with the positioning hole diameter of the bridge plate (4). Select main locating pins and auxiliary locating pins (10) with the same maximum end diameter based on the diameter of the main locating hole before machining, the main locating hole after machining, and the auxiliary locating hole before machining on the part.

2. The fixture device for flexible machining of precision holes in aircraft titanium alloy butt joints according to claim 1, characterized in that, Also includes: Ear plate pressure plate (11) and jack and attached pressure plate (12); Before machining the positioning holes on the part, and when the main positioning pin and the auxiliary positioning pin (10) are both inserted into the main positioning hole base (2) and the auxiliary positioning hole base (3), the ear plate pressure plate (11) and the jack and the attached pressure plate (12) are respectively set at the ear end of the part and the end away from the ear plate.

3. The fixture device for flexible machining of precision holes in aircraft titanium alloy butt joints according to claim 1, characterized in that, The distance between the auxiliary positioning hole base (3) and the main positioning hole base (2) is adjusted according to the distance between the holes on the part.

4. The fixture device for flexible machining of precision holes in aircraft titanium alloy butt joints according to claim 1, characterized in that, The perpendicularity between the axis of the positioning hole and the top surface of the bridge plate (4) is within 0.03mm.

5. The fixture device for flexible machining of precision holes in aircraft titanium alloy butt joints according to claim 1, characterized in that, The flatness of the top surface of the bridge plate (4) is within 0.02mm.

6. The fixture device for flexible machining of precision holes in aircraft titanium alloy butt joints according to claim 1, characterized in that, The parallelism between the line connecting the positioning holes on the bridge plate (4) and the alignment edge of the fixture body (1) is within 0.03mm.

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