Milling machine flexible clamp for machining flange plate

Abstract

The invention relates to a milling machine flexible clamp for machining a flange plate, and belongs to the technical field of technological equipment design and manufacturing. According to the flexible milling jig for the flange plate, the positioning mandrel and the positioning bush are rapidly replaced, the position of the positioning pin is adjusted, and the purpose of rapid remodeling is achieved. The flexible clamp can replace a special clamp, meets the milling and clamping requirements of all flange plate parts, fundamentally solves the problems that the number of special tools on a production site is large, and the production and management cost is high, effectively guarantees the operation of a production line, and also plays a great role in improving the production efficiency.

Description

Technical Field

[0001] The invention relates to a flexible fixture of a milling machine used for machining a flange, and belongs to the technical field of process equipment design and manufacturing. Background Art

[0002] Flange parts account for a large proportion of aircraft parts. They are a common type of rotating parts with simple structure, single form and low processing difficulty. Flange parts have a high degree of structural similarity and high consistency in process flow, which is conducive to the application of group processing mode.

[0003] At present, the processing flow of flange parts has been basically solidified: rough turning reference, drilling - fine turning end face, outer circle - fine turning end face, outer circle, ring groove, inner hole - drilling - milling outer shape. When turning, use three jaws to clamp the outer circle of the part to complete the turning process. When drilling, use the outer circle of the flange as the reference, use three jaws to position and clamp, and then you can drill. When milling the outer shape, you need to use special tooling for positioning and clamping to ensure that the milled shape is consistent with the position of the bolt hole.

[0004] Due to the different diameters of flange conduits and the sizes and positions of bolt holes, the required sizes of positioning elements are also varied. Different special tooling is required to produce flanges of different specifications, which seriously increases the production and management costs of tooling. When processing different flanges, special process equipment must be replaced, which objectively leads to the inconsistency of the production process, increases production preparation time, and affects the improvement of production efficiency.

[0005] Therefore, whether from the perspective of reducing changeover time or from the perspective of reducing tooling management costs, it is necessary to design an efficient and flexible quick-change tooling to ensure efficient operation of the production line. Summary of the invention

[0006] In order to solve the technical problem of too many special milling machine fixtures and difficulty in changing models on the flange production line, the present invention has designed a flexible fixture that can meet the clamping needs of various flange parts during milling processing. It can greatly reduce the number of special tooling on the production line and reduce production and management costs, while also ensuring the continuity of the production line, shortening production preparation time and improving production efficiency.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] A flexible fixture for a milling machine used for machining a flange comprises a fixture body, a positioning element and a clamping element.

[0009] The fixture body includes two parts, a base and a fixing bolt, and standard parts such as bolts, spring washers and self-locking nuts, which are used to support and fix the flange parts. The positioning element includes a positioning spindle, an adjustable positioning pin composed of a movable base and a quick-release stop pin, a positioning bushing, a spring, a spring washer and a nut, and other parts and standard parts, which are used to position the flange parts on the fixture body. The clamping element includes a pressure plate and a nut, which are used to clamp and fix the flange parts after positioning.

[0010] The structure of the flexible clamp is shown in FIG1 , and is specifically as follows.

[0011] The base is shown in Figure 2 and is used to support and fix the flange. Figure 4 The bolt holes on the corners are used to fix the base to the milling machine table. The two extended holes are used for the movement and adjustment of the positioning pin body. The slot width size and the positioning pin body are matched with clearance to ensure that the pin body can move flexibly in a free state and is easy to adjust. The bolt hole and hexagonal slot in the middle are used to install the fixing bolts.

[0012] The fixing bolt and the base are fixed by welding to form a whole, ensuring that the axis of the fixing bolt is vertical. At the same time, the thread length of the selected bolt should be adapted to the positioning mandrel, and the clearance between the bolt diameter and the bolt hole should be small, which is conducive to preventing welding deformation and ensuring that the bolt axis is vertical.

[0013] As attached Figure 3 As shown, bolts, spring washers and self-locking nuts are used to fix the base to one end of the workbench. The flange milling clamp is a commonly used tooling that can be fixed to one end of the workbench of the CNC milling machine, which not only avoids frequent disassembly but also leaves sufficient space for installing tooling for other parts.

[0014] The positioning spindle is as shown in the attached Figure 4 As shown, the inner hole of the mandrel matches the fixing bolt, and the smaller the gap, the better. The outer circle of the mandrel is used to locate the inner hole of the flange, constraining the five degrees of freedom of X, Y, Z, A, and B. In order to facilitate the installation and replacement of the positioning mandrel, the mandrel is slotted. In order to facilitate the installation of parts, the mandrel is chamfered.

[0015] As attached Figure 5 As shown, a hexagonal thin nut is used to fix the positioning spindle on the base. In order to ensure the effective positioning length of the positioning spindle, the length of the spindle should be guaranteed to be a certain length. Considering the length limit of the flange, it is advisable to use a thin nut to fix the spindle.

[0016] The adjustable positioning pin is shown in Figure 6, which consists of a movable base and a quick-release stop pin. The base and the quick-release stop pin are connected by threads, and the coaxiality between the base and the stop pin must be ensured to be no greater than 0.05. The base is fixed in the extension hole of the fixture base with a spring washer and a nut, as shown in the attached Figure 7 The base and the extended hole of the base are clearance matched, the clearance is not greater than 0.05, and the surface roughness of the matching surface is Ra≤0.8.

[0017] The positioning bushing is as attached Figure 8 As shown, the inner hole matches the outer circle of the quick-release stop pin, the matching clearance is not greater than 0.05, and the surface roughness of the matching surface is Ra≤0.8. The outer circle is processed according to the size of the flange bolt hole. According to the size of the bolt hole, the bushing is serialized. It can be made according to a single size, or the sizes can be combined to make a "tower-shaped" bushing for selection as needed during processing.

[0018] The pressing plate has a shape and structure similar to that of the positioning mandrel, and only has a smaller thickness than the mandrel, so as to reduce the milling depth of the flange shape, ensure the milling rigidity of the parts, and improve the processability and processing quality.

[0019] A method for using a flexible fixture for milling flange parts, the steps are as follows:

[0020] Step 1: Preparation of the clamping concrete. Install the fixing bolts on the base and connect the two from the bottom by welding.

[0021] Step 2: Fix the clamp body. Use bolts, spring washers and self-locking nuts to install the clamp body on the workbench of the machine tool.

[0022] Step 3: Installation of adjustable locating pin. From the bottom of the base, install the movable base of the locating pin into the extended hole of the fixture base, install the spring washer and nut from the top, leaving 1 to 2 pitches, no need to tighten. Install the quick-release stop pin on the base and tighten.

[0023] Step 4: Installation of the positioning mandrel. According to the inner diameter of the flange conduit to be processed, select a positioning mandrel of corresponding specifications, and install the mandrel on the fixing bolt from the side. It is recommended to fit the inner hole with the outer circle of the bolt along the X-axis direction from left to right, and then use a hexagonal thin nut to fix the positioning mandrel on the clamp body to ensure that the mandrel fits the outer circle of the bolt. The hexagonal thin nut can be fixed with a spring washer as needed.

[0024] Step 5: Installation of the positioning bushing. First install the spring on the quick-release stop pin, and then select the corresponding positioning bushing according to the diameter of the flange bolt hole and install it on the stop pin. In order to make the adjustment range of the bushing large enough, a spring with a larger compression range should be selected.

[0025] Step 6: Adjust the position of the locating pin. Confirm that the movable base is in a relaxed state, install the flange to be processed from top to bottom on the locating bushing, move the base so that the inner hole of the flange conduit is installed on the locating mandrel. Press the part and install the pressure plate from the side. Press the pressure plate and tighten the nut to fix the part. Tighten the movable base of the locating pin to fix the locating pin. At this time, the flexible fixture has completed the changeover.

[0026] Step 7: Install the parts. Install the parts from top to bottom, use the mandrel and bushing to position them, install the pressure plate from the side, and tighten the nuts to secure them.

[0027] Step 8: Disassembly of parts. Loosen the nut, remove the pressure plate from the side, and then remove the parts from bottom to top.

[0028] Step 9: Change the shape of the fixture. The shape of the fixture can be changed according to steps 4 to 6.

[0029] Beneficial effects of the present invention:

[0030] The flange flexible milling machine fixture provided by the present invention can achieve the purpose of rapid changeover by quickly replacing the positioning spindle and positioning bushing and adjusting the position of the positioning pin. This flexible fixture can replace special fixtures and meet the milling and clamping requirements of all flange parts, fundamentally solving the problem of a large number of special tooling at the production site and high production and management costs, effectively ensuring the operation of the production line, and also having a great effect on improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] FIG. 1( a ) is a structural side view of a flexible milling clamp;

[0032] Figure 1(b) is an AA cross-sectional view of the flexible milling clamp;

[0033] Figure 1(c) is a top view of the flexible milling clamp;

[0034] FIG2( a ) is a structural perspective view of the fixture base;

[0035] FIG2( b ) is a structural side view of the fixture base;

[0036] FIG2( c ) is a top view of the structure of the fixture base;

[0037] Figure 3 This is a schematic diagram of the installation of the base on the milling machine table;

[0038] Figure 4 It is a structural schematic diagram of the positioning mandrel;

[0039] Figure 5 It is a schematic diagram of the installation of the positioning mandrel on the fixture base;

[0040] FIG6( a ) is a side view of an adjustable positioning pin;

[0041] FIG6( b ) is a front view of the adjustable positioning pin;

[0042] Figure 7 It is a schematic diagram of the installation of the adjustable positioning pin on the fixture base;

[0043] Figure 8 It is a structural schematic diagram of the positioning bushing;

[0044] Among them, 1. bolt, 2. spring washer, 3. self-locking nut, 4. base, 5. movable base, 6. fixing bolt, 7. positioning spindle, 8. hexagonal thin nut, 9. pressure plate, 10. nut, 11. spring washer, 12. nut, 13. spring, 14. positioning bushing, 15. quick release stop pin, 16. alternative pressure plate group, 17. alternative positioning spindle group, 18. alternative positioning bushing group. DETAILED DESCRIPTION

[0045] Embodiment 1:

[0046] A flexible fixture for a milling machine used for machining a flange comprises a fixture body, a positioning element and a clamping element.

[0047] The fixture body includes two parts, a base 4 and a fixing bolt 6, and standard parts such as a bolt 1, a spring washer 2, and a self-locking nut 3, which are used to support and fix the flange parts. The positioning element includes a positioning spindle 7, an adjustable positioning pin composed of a movable base 5 and a quick-release stop pin 15, a positioning bushing 14, a spring 13, a spring washer 11, and a nut 12, and other parts and standard parts, which are used to position the flange parts on the fixture body. The clamping element includes a pressure plate 9 and a nut No. 10, which is used to clamp and fix the flange parts after positioning.

[0048] The structure of the flexible clamp is shown in FIG1 , and is specifically as follows.

[0049] The base 4 is shown in FIG2 and is used to support and fix the flange. Figure 4 The bolt holes on the corners are used to fix the base to the milling machine table. The two extended holes are used for the movement and adjustment of the positioning pin body. The slot width size and the positioning pin body are matched with clearance to ensure that the pin body can move flexibly in a free state and is easy to adjust. The bolt hole and hexagonal slot in the middle are used to install the fixing bolts.

[0050] The fixing bolt 6 and the base 4 are fixed by welding to form a whole, so as to ensure that the axis of the fixing bolt is vertical. At the same time, the thread length of the selected bolt should be adapted to the positioning mandrel, and the clearance between the bolt diameter and the bolt hole should be small, which is conducive to preventing welding deformation and ensuring that the bolt axis is vertical.

[0051] As attached Figure 3 As shown, the base 4 is fixed to one end of the workbench using bolts 1, spring washers 2, and self-locking nuts 3. The flange milling clamp is a commonly used tooling that can be fixed to one end of the workbench of a CNC milling machine, which not only avoids frequent disassembly but also leaves sufficient space for installing tooling for other parts.

[0052] The positioning spindle 7 is as shown in the attached Figure 4 As shown, the inner hole of the mandrel matches the fixing bolt, and the smaller the gap, the better. The outer circle of the mandrel is used to locate the inner hole of the flange, constraining the five degrees of freedom of X, Y, Z, A, and B. In order to facilitate the installation and replacement of the positioning mandrel, the mandrel is slotted. In order to facilitate the installation of parts, the mandrel is chamfered.

[0053] As attached Figure 5 As shown, the positioning spindle is fixed to the base using a hexagonal thin nut 8. In order to ensure the effective positioning length of the positioning spindle, the length of the spindle should be guaranteed to be a certain length. Considering the length limit of the flange, it is appropriate to use a thin nut to fix the spindle.

[0054] The adjustable positioning pin is shown in Figure 6, which consists of a movable base 5 and a quick-release stop pin 15. The base and the quick-release stop pin are connected by threads, and the coaxiality between the base and the stop pin must be ensured to be no greater than 0.05. The base is fixed in the extended hole of the fixture base by a spring washer 11 and a nut 12. Figure 7 The base and the extended hole of the base are clearance matched, the clearance is not greater than 0.05, and the surface roughness of the matching surface is Ra≤0.8.

[0055] The positioning bushing 14 is as shown in the attached Figure 8 As shown, the inner hole matches the outer circle of the quick-release stop pin 15, the matching clearance is not greater than 0.05, and the surface roughness of the matching surface is Ra≤0.8. The outer circle is processed according to the size of the flange bolt hole. According to the size of the bolt hole, the bushing is serialized. It can be made according to a single size, or the sizes can be combined to make a "tower-shaped" bushing for selection as needed during processing.

[0056] The pressing plate 9 is similar in shape and structure to the positioning mandrel, but has a smaller thickness than the mandrel, so as to reduce the milling depth of the flange shape, ensure the milling rigidity of the parts, and improve the processability and processing quality.

[0057] Embodiment 2:

[0058] A method for using a flexible fixture for milling flange parts, the steps are as follows:

[0059] Step 1: Preparation of the clamping structure: Install the fixing bolts 6 on the base 4 and connect the two from the bottom by welding.

[0060] Step 2: Fix the clamp body. Use bolts 1, spring washers 2, and self-locking nuts 3 to install the clamp body on the workbench of the machine tool.

[0061] Step 3: Installation of adjustable locating pin. From the bottom of the base, install the movable base 5 of the locating pin into the extended hole of the fixture base 4, and install the spring washer 11 and nut 12 from the top, leaving 1 to 2 pitches without tightening. Install the quick-release stop pin 15 on the base and tighten it.

[0062] Step 4: Installation of the positioning mandrel. According to the inner diameter of the flange conduit to be processed, select the positioning mandrel 7 of the corresponding specification, and install the mandrel on the fixing bolt from the side. It is recommended to fit the inner hole with the outer circle of the bolt from left to right along the X-axis direction, and then use the hexagonal thin nut 8 to fix the positioning mandrel on the clamp body to ensure that the mandrel fits the outer circle of the bolt. The hexagonal thin nut 8 can be fixed with a spring washer as needed.

[0063] Step 5: Installation of the positioning bushing. First install the spring 13 on the quick-release stop pin 15, and then select the corresponding positioning bushing 14 according to the diameter of the flange bolt hole and install it on the stop pin. In order to make the adjustment range of the bushing large enough, a spring with a larger compression range should be selected.

[0064] Step 6: Adjust the position of the locating pin. Confirm that the movable base is in a relaxed state. When changing the model, you should first loosen the locking nut on the base, install the flange to be processed from top to bottom on the positioning bushing, move the base, and install the inner hole of the flange conduit on the positioning mandrel. Press the part and install the pressure plate 9 from the side. Press the pressure plate and tighten the nut 10 to fix the part. Tighten the movable base of the locating pin to fix the locating pin. At this time, the flexible fixture has completed the model change.

[0065] Step 7: Installation of parts. The parts are installed from top to bottom, and after positioning with the mandrel and bushing, the pressure plate 9 is installed from the side and the nut 10 is tightened to fix it.

[0066] Step 8: Disassembly of parts. Loosen the nut 10, remove the pressure plate 9 from the side, and then remove the parts from bottom to top.

[0067] Step 9: Change the shape of the fixture. The shape of the fixture can be changed according to steps 4 to 6.

Claims

1. A flexible fixture for a milling machine used for machining flanges, characterized in that: It includes a fixture body, a positioning element, and a clamping element; The clamp body comprises two parts, namely a base (4) and a fixing bolt (6), and standard parts such as a bolt (1), a spring washer (2) and a self-locking nut (3), which are used to support and fix the flange parts; The positioning element comprises a positioning spindle (7), an adjustable positioning pin composed of a movable base (5) and a quick-release stop pin (15), a positioning bushing (14), a spring (13), a spring washer (11) and a nut (12) and other parts and standard parts, which are used for positioning the flange part on the fixture body; The clamping element comprises a pressing plate (9) and a nut (10), which are used for clamping and fixing the flange parts after positioning; The base (4) is used to support and fix the flange, and the two elongated holes are used for movement and adjustment of the positioning pin body, and the slot width size thereof is clearance-matched with the positioning pin body; The fixing bolt (6) and the base (4) are fixed by welding to form a whole, so as to ensure that the axis of the fixing bolt is vertical; at the same time, the thread length of the selected bolt should be compatible with the positioning spindle (7), and the clearance between the bolt diameter and the bolt hole should be small, which is conducive to preventing welding deformation and ensuring that the axis of the bolt is vertical; The base (4) is fixed to one end of the workbench by bolts (1), spring washers (2) and self-locking nuts (3); the flange milling clamp is a commonly used tooling and is fixed to one end of the workbench of the CNC milling machine; The inner hole of the positioning mandrel (7) is matched with the fixing bolt, and the smaller the gap, the better; the outer circle of the mandrel is used to position the inner hole of the flange, constraining the five degrees of freedom of X, Y, Z, A, B, etc. A hexagonal thin nut (8) is used to fix the positioning spindle on the base, and a thin nut is used to fix the spindle; The adjustable positioning pin is composed of a movable base (5) and a quick-release stop pin (15); the movable base (5) is fixed in the extension hole of the clamp base by using a spring washer (11) and a nut (12); the movable base (5) and the extension hole of the base are clearance-matched, the clearance is not greater than 0.05, and the surface roughness of the matching surface is Ra≤0.8; The shape and structure of the pressing plate (9) are similar to those of the positioning mandrel, except that its thickness is smaller than that of the mandrel.

2. A flexible fixture for a milling machine used for machining flanges as claimed in claim 1, characterized in that: The base (4) is provided in the middle with a bolt hole and a hexagonal groove for installing a fixing bolt.

3. A flexible fixture for a milling machine used for machining flanges as claimed in claim 1 or 2, characterized in that: The mandrel of the positioning mandrel (7) is grooved and has a guiding chamfer.

4. A flexible fixture for a milling machine used for machining flanges as claimed in claim 1 or 2, characterized in that: The movable base (5) and the quick-release stop pin are connected by threaded connection, and the coaxiality between the base and the stop pin must be no greater than 0.

05.

5. A flexible fixture for a milling machine used for machining flanges as claimed in claim 3, characterized in that: The movable base (5) and the quick-release stop pin are connected by threaded connection, and the coaxiality between the base and the stop pin must be no greater than 0.

05.

6. A flexible fixture for a milling machine used for machining flanges as claimed in claim 1, 2 or 5, characterized in that: The inner hole of the positioning bushing (14) is matched with the outer circle of the quick-release stop pin (15), the matching clearance is not greater than 0.05, and the surface roughness of the matching surface is Ra≤0.

8.

7. A flexible fixture for a milling machine used for machining flanges as claimed in claim 3, characterized in that: The inner hole of the positioning bushing (14) is matched with the outer circle of the quick-release stop pin (15), the matching clearance is not greater than 0.05, and the surface roughness of the matching surface is Ra≤0.

8.

8. A flexible fixture for a milling machine used for machining flanges as claimed in claim 4, characterized in that: The inner hole of the positioning bushing (14) is matched with the outer circle of the quick-release stop pin (15), the matching clearance is not greater than 0.05, and the surface roughness of the matching surface is Ra≤0.

8.

9. A method for using the flexible fixture for a milling machine according to any one of claims 1 to 8, characterized in that: Here are the steps: Step 1: Preparation of the clamping structure; installing the fixing bolts (6) on the base (4) and fastening the two together from the bottom by welding; Step 2: Fixing the clamp body; Use bolts (1), spring washers (2), and self-locking nuts (3) to install the clamp body on the workbench of the machine tool; Step 3: Install the adjustable locating pin; from the bottom of the base, install the movable base (5) of the locating pin into the extended hole of the fixture base (4), install the spring washer (11) and nut (12) from the top, leaving 1 to 2 thread pitches, and no need to tighten; install the quick-release stop pin (15) on the base and tighten; Step 4: Install the positioning mandrel; select a positioning mandrel (7) of corresponding specifications according to the inner diameter of the flange conduit to be processed, and install the mandrel on the fixing bolt from the side. It is recommended that the inner hole fits the outer circle of the bolt along the X-axis direction from left to right, and then use a hexagonal thin nut (8) to fix the positioning mandrel on the clamp body to ensure that the mandrel fits the outer circle of the bolt. The hexagonal thin nut (8) can be fixed with a spring washer as needed; Step 5: Installation of the positioning bushing; first install the spring (13) on the quick-release stop pin (15), and then select a positioning bushing (14) of corresponding specifications according to the diameter of the flange bolt hole and install it on the stop pin; in order to make the adjustment range of the bushing large enough, a spring with a larger compression range should be selected; Step 6: Adjust the position of the locating pin; confirm that the movable base is in a relaxed state (the locking nut on the base should be loosened first when changing the model), install the flange to be processed from top to bottom on the positioning bushing, move the base so that the inner hole of the flange guide tube is installed on the positioning spindle; press the part and install the pressure plate (9) from the side; press the pressure plate and tighten the nut (10) to fix the part; tighten the movable base of the locating pin to fix the locating pin; at this time, the flexible fixture has completed the model change; Step 7: Install the parts from top to bottom, position them with the mandrel and bushing, install the pressure plate (9) from the side, and tighten the nut (10) to fix them; Step 8: Disassembly of parts: loosen the nut (10), remove the pressure plate (9) from the side, and then remove the parts from bottom to top; Step 9: Change the shape of the fixture; the fixture can be changed according to steps 4 to 6.

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