Four-axis machining tooling for electromagnetic valve thin-wall castings

Abstract

The application relates to a four-axis machining tool for an electromagnetic valve thin-wall casting and relates to the field of clamp tooling, which comprises a tool main body, a bidirectional clamping mechanism and a limiting block, clamping blocks are fixed on the two sides of the bidirectional clamping mechanism, the bidirectional clamping mechanism is used for driving the clamping blocks to move in the direction of approaching or moving away from the limiting block, the opposite surfaces of the clamping blocks and the limiting block are both provided with profiling surfaces, the profiling surfaces comprise rigid clamping areas and semi-rigid clamping areas, the semi-rigid clamping areas are covered with silica gel layers, the thickness of the silica gel layers is 1.8-2.0 mm, and the hardness of the silica gel layers is Shore hardness 45A-50A. The application has the effect of improving the machining precision of the thin-wall casting.

Description

Technical Field

[0001] This application relates to the field of fixtures and tooling, and in particular to a four-axis machining fixture for thin-walled solenoid valve castings. Background Technology

[0002] Some solenoid valves use castings for their valve bodies. These castings are then clamped by fixtures and tooling. A four-axis machining center is used to perform surface milling, drilling of flow channel holes, machining of threaded holes, and machining of mounting holes. Depending on the application scenario of the solenoid valve, thin-walled castings may be used to simplify the structural dimensions and reduce weight. Thin-walled castings often have the structure of thin-walled tubes.

[0003] Existing fixtures for castings with complex shapes often use a contour-following surface for the clamping blocks. This contour-following surface adapts to the complex shape of the casting, ensuring that the clamping blocks can clamp as many parts of the outer surface of the casting as possible, thereby improving clamping stability.

[0004] However, due to the machining errors of the contour surface, the contour surface and the outer surface of the casting are not in ideal surface contact, but rather in local point or line contact. That is, there are situations where some parts of the casting are clamped and abutted, while other parts have gaps. In this case, it is often necessary to increase the clamping force so that even if the casting is not fully clamped, the stability of clamping and machining accuracy can be ensured.

[0005] However, while increasing clamping force is acceptable for thick-walled castings, it's problematic for thin-walled castings, particularly those with thin-walled tubular structures. Increasing the clamping force can easily ellipse the thin-walled tube. In this state, machining the inner hole of the tube will result in a round hole, but after releasing the clamp, the hole will become elliptical, leading to significant machining errors. Conversely, setting the clamping force too low, just enough to prevent deformation of the thin-walled tube, results in poor overall clamping stability due to the rigid contouring surface failing to provide effective multi-point clamping. This makes the casting prone to slight movement or deviation under machining forces, further increasing machining errors. Summary of the Invention

[0006] To improve the machining accuracy of thin-walled castings, this application provides a four-axis machining fixture for thin-walled solenoid valve castings.

[0007] This application provides a four-axis machining fixture for thin-walled solenoid valve castings, employing the following technical solution: A four-axis machining fixture for thin-walled solenoid valve castings includes a fixture body, a bidirectional clamping mechanism, and a limiting block. The bidirectional clamping mechanism has clamping blocks fixed on both sides and is used to drive the clamping blocks to move toward or away from the limiting block. The opposing surfaces of the clamping blocks and the limiting block are both set as contoured surfaces. The contoured surfaces include a rigid clamping area and a semi-rigid clamping area. The semi-rigid clamping area is covered with a silicone layer with a thickness of 1.8-2.0 mm and a Shore hardness of 45A-50A.

[0008] By adopting the above technical solution, and by defining a rigid clamping zone and utilizing a silicone layer as a semi-rigid clamping zone, under high clamping force, the rigid clamping zone can stably clamp the thick-walled, high-rigidity parts of the thin-walled casting through conformal contact. Meanwhile, by limiting the thickness and hardness of the silicone layer, the semi-rigid clamping zone possesses a certain compressibility and rigidity. First, the silicone layer can deform to conform to the outer surface of the thin-walled tube of the casting, resulting in a more balanced distribution of clamping force and reducing stress concentration caused by localized hard extrusion, which could lead to ellipticing of the thin-walled tube. Second, the compressive reaction force of the silicone layer increases more gradually than the clamping force of the rigid clamping zone, meaning the clamping force on the thin-walled tube is limited to a certain range and does not increase linearly with the total clamping force of the clamping blocks or limiting blocks. Finally, through conformal clamping of the rigid and semi-rigid clamping zones, the clamping stability of the thin-walled casting is comprehensively improved, and the degree of clamping deformation is reduced, thereby improving machining accuracy.

[0009] Optionally, the bidirectional clamping mechanism is provided as two and arranged at intervals along the length direction of the tooling body.

[0010] Optionally, the bidirectional clamping mechanism includes a fastening bolt, a control block, and two displacement blocks. Each side of the control block is provided with an inclined T-shaped block. The displacement blocks are slidably connected to the tooling body along the length of the tooling body. The sides of the displacement blocks have inclined T-shaped grooves, and the T-shaped blocks slide with the T-shaped grooves. The fastening bolt is perpendicularly inserted into the first control block and is threadedly engaged with the tooling body. The displacement blocks are fixedly connected to the clamping block.

[0011] Optionally, a support platform is protruding from one surface of the tooling body, the displacement block is slidably connected to the support platform along the length direction of the tooling body, and the limiting block is fixed to the support platform.

[0012] Optionally, the support platform is elongated.

[0013] Optionally, the clamping block includes a first block, a first clamping member, a first locking block, and a first bolt. The first block has the rigid clamping area and is fixed to the bidirectional clamping mechanism. The first clamping member has the semi-rigid clamping area and slides with the first block. The first locking block slides with the first block in a direction perpendicular to the main body of the tooling. The first bolt is used to limit the sliding position of the first locking block. The first locking block has a first inclined surface, and the first clamping member has a second inclined surface that mates with the first inclined surface. The limiting block includes a second block, a second clamping member, a second locking block, and a second bolt. The second block is fixed to the bidirectional clamping mechanism. The second block has the semi-rigid clamping area. The second clamping member slides with the second block, and the second locking block slides with the second block in a direction perpendicular to the main body of the tooling. The second bolt is used to limit the sliding position of the second locking block. The second locking block has a third inclined surface, and the second clamping member has a fourth inclined surface that mates with the third inclined surface.

[0014] Optionally, the first clamping member includes a first central clamping block and two first side clamping blocks. The sliding direction of the first central clamping block is the length direction of the tooling body, and the sliding direction of the first side clamping blocks is the radial direction of the thin-walled tube body of the thin-walled casting. One side of the first central clamping block and the two first side clamping blocks are the semi-rigid clamping area, and the other side of the first central clamping block and the two first side clamping blocks are the second inclined surface. The second clamping member includes a second central clamping block and two second side clamping blocks. The sliding direction of the second central clamping block is the length direction of the tooling body, and the sliding direction of the second side clamping blocks is the radial direction of the thin-walled tube body of the thin-walled casting. One side of the second central clamping block and the two second side clamping blocks are the semi-rigid clamping area, and the other side of the second central clamping block and the two second side clamping blocks are the fourth inclined surface.

[0015] Optionally, an adaptive force-equalizing pre-clamping structure is also included. The first block is slidably connected to a first pioneer block along a direction perpendicular to the main body of the tooling. The first pioneer block has a fifth inclined surface, and the first middle clamping block has a sixth inclined surface, the inclination angle of which is smaller than that of the second inclined surface. The second block is slidably connected to a second pioneer block along a direction perpendicular to the main body of the tooling. The second pioneer block has a seventh inclined surface, and the second middle clamping block has an eighth inclined surface, the inclination angle of which is smaller than that of the fourth inclined surface. The first middle clamping block is elastically connected to a first side clamping block, and the second middle clamping block is elastically connected to a second side clamping block. The adaptive force-equalizing pre-clamping structure is used to simultaneously apply the same downward pulling force to the first pioneer block and the second pioneer block, so that the first middle clamping block, the first side clamping block, the second middle clamping block, and the second side clamping block move to the outer peripheral surface of the thin-walled tube of the thin-walled casting. During this process, the first side clamping block moves to the abutment position before the first middle clamping block, and the second side clamping block moves to the abutment position before the second middle clamping block.

[0016] Optionally, the adaptive force equalization pre-clamping structure includes a traction rope, a steel ball, a slider, a first guide wheel, a second guide wheel, and a drive rod. The first guide wheel is located below the first block and is fixed relative to the first block. The second guide wheel is located below the second block and is fixed relative to the second block. A vertical groove is provided at the bottom of the tooling body. The length direction of the slider is the length direction of the tooling body. The slider has a slide rail groove arranged along its own length direction. The slider slides and engages with the slide rail groove in a direction perpendicular to the tooling body. The steel ball slides and engages with the slide rail groove. The steel ball has an annular groove. The steel ball is higher than the first guide wheel and located at the middle position between the first guide wheel and the second guide wheel. One end of the traction rope is fixed to the first pilot block. The other end of the traction rope extends downward and around the first guide wheel, extends obliquely upward and around the annular groove of the steel ball, extends obliquely downward and around the second guide wheel, and extends upward and is fixed to the second pilot block. The drive rod has a sliding section and a threaded section. The drive rod is threadedly connected to the tooling body. The end of the drive rod abuts against the bottom of the slider. The drive rod is used to lift the slider.

[0017] Optionally, the silicone layer thickness of the first middle clamping block is greater than the silicone layer thickness of the first side clamping block, and the silicone layer thickness of the second middle clamping block is greater than the silicone layer thickness of the second side clamping block.

[0018] In summary, this application includes at least one of the following beneficial technical effects: By defining a rigid clamping zone and utilizing a silicone layer as a semi-rigid clamping zone, under high clamping force, the rigid clamping zone can stably clamp the thick-walled, high-rigidity parts of the thin-walled casting through conformal contact. Meanwhile, by limiting the thickness and hardness of the silicone layer, the semi-rigid clamping zone possesses a certain degree of compressibility and rigidity. First, the silicone layer can deform to conform to the outer surface of the thin-walled tube of the casting, resulting in a more balanced distribution of clamping force and reducing stress concentration caused by localized hard extrusion, which could lead to ellipticing of the thin-walled tube. Second, the compressive reaction force of the silicone layer increases more gradually than the clamping force of the rigid clamping zone, meaning the clamping force on the thin-walled tube is limited to a certain range and does not increase linearly with the total clamping force of the clamping blocks or limiting blocks. Finally, through conformal clamping of the rigid and semi-rigid clamping zones, the clamping stability of the thin-walled casting is comprehensively improved, and the degree of clamping deformation is reduced, thereby improving machining accuracy. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of Example 1.

[0020] Figure 2 This is a schematic diagram of the clamping block in Example 1.

[0021] Figure 3This is a schematic diagram of the bidirectional clamping mechanism of Embodiment 1.

[0022] Figure 4 This is a schematic diagram of the overall structure of Example 2.

[0023] Figure 5 This is an exploded view of the clamping block and limiting block of Embodiment 2.

[0024] Figure 6 This is a schematic diagram of the overall structure of Example 3.

[0025] Figure 7 This is a top view of the clamping block and limiting block of Embodiment 3.

[0026] Figure 8 This is an exploded view of the clamping block and limiting block of Embodiment 3.

[0027] Figure 9 This is a partial schematic diagram of the overall structure of Example 4.

[0028] Figure 10 This is a top view of the clamping block and limiting block in Embodiment 4.

[0029] Figure 11 This is a partial cross-sectional view of the overall structure of Example 4.

[0030] Figure 12 This is a top view of the clamping block and limiting block in Embodiment 4.

[0031] Explanation of reference numerals in the attached drawings: 1. Clamping block; 2. Limiting block; 100. Thin-walled casting; 200. Thin-walled tube body; 10. Tooling body; 101. Support platform; 102. Slide groove; 11. Semi-rigid clamping area; 12. Rigid clamping area; 13. First block; 14. First guide groove; 15. First clamping component; 150. Second inclined surface; 151. First middle clamping block; 152. First side clamping block; 153. Sixth inclined surface; 154. First clearance groove; 16. First locking block; 161. First inclined surface; 17. First bolt; 18. Mounting groove; 181. Vertical bar; 182. Elastic bar; 183. Slot; 20. Bidirectional clamping mechanism; 201. Control block; 202. Displacement block; 203. Tightening... 204. Fastening bolt; 205. T-slot; 21. Second block; 22. Second clamping member; 220. Fourth inclined surface; 221. Second middle clamping block; 222. Second side clamping block; 223. Eighth inclined surface; 224. Second clearance groove; 23. Second locking block; 231. Third inclined surface; 24. Second guide groove; 25. Second bolt; 30. First pilot block; 301. Fifth inclined surface; 31. Second pilot block; 311. Seventh inclined surface; 32. Traction rope; 33. Drive rod; 331. Sliding section; 332. Threaded section; 34. Sliding bar; 341. Slide rail groove; 35. Steel ball; 351. Ring groove; 36. First guide wheel; 361. Support rod; 37. Second guide wheel. Detailed Implementation

[0032] The following is in conjunction with the appendix Figure 1 -Appendix Figure 12 This application will be described in further detail.

[0033] Example 1 discloses a four-axis machining fixture for thin-walled solenoid valve castings. (Refer to...) Figure 1 The four-axis machining fixture for thin-walled solenoid valve castings includes a fixture body 10, a bidirectional clamping mechanism 20, and limiting blocks 2. The fixture body 10 is a horizontally arranged elongated strip, with both ends used for mounting and fixing to the rotating shaft of the four-axis machining center. A support platform 101 protrudes from the upper surface of the fixture body 10, and the support platform 101 is elongated. Two bidirectional clamping mechanisms 20 are provided and arranged at intervals along the length of the fixture body 10. Multiple limiting blocks 2 are provided, with two limiting blocks 2 corresponding to one bidirectional clamping mechanism 20. The limiting blocks 2 are fixed to the support platform 101, and the two limiting blocks 2 are located on both sides of the bidirectional clamping mechanism 20. Clamping blocks 1 are fixed on both sides of the bidirectional clamping mechanism 20. The driving direction of the bidirectional clamping mechanism 20 is the length direction of the fixture body 10, and the bidirectional clamping mechanism 20 is used to drive the clamping blocks 1 to move toward or away from the corresponding limiting block 2.

[0034] like Figure 1 and Figure 2As shown, the opposing surfaces of clamping block 1 and limiting block 2 are both designed as contoured surfaces, that is, clamping block 1 and limiting block 2 have the same contoured surfaces. The contoured surfaces include a rigid clamping area 12 and a semi-rigid clamping area 11. The rigid clamping area 12 is used to abut against the thick-walled part of the thin-walled casting 100. The semi-rigid clamping area 11 is covered with a silicone layer (not shown in the figure). The thickness of the silicone layer is 1.8-2.0 mm, and the hardness of the silicone layer is Shore hardness 45A-50A. The semi-rigid clamping area 11 is used to contact the thin-walled tube body 200 of the thin-walled casting 100.

[0035] like Figure 3 As shown, the bidirectional clamping mechanism 20 includes a fastening bolt 203, a control block 201, and two displacement blocks 202. The two displacement blocks 202 are respectively arranged on both sides of the control block 201 along the length of the tooling body 10. The control block 201 is a trapezoidal block, and both inclined sides of the control block 201 are provided with inclined T-shaped blocks 204. The displacement blocks 202 are slidably connected to the support platform 101 along the length of the tooling body 10. The specific structure of this sliding connection can be a T-shaped sliding structure to ensure that the sliding does not come off. The inclined sides of the displacement blocks 202 have inclined T-shaped grooves 205. The T-shaped blocks 204 slide and cooperate with the T-shaped grooves 205. The fastening bolt 203 is vertically inserted into the first control block 201. The fastening bolt 203 is threadedly engaged with the tooling body 10, and the thread head of the fastening bolt 203 abuts against the upper surface of the control block 201.

[0036] The displacement block 202 is fixedly connected to the clamping block 1.

[0037] In this way, the control block 201 is moved down by the fastening bolt 203. The control block 201 slides and engages with the T-shaped block 204 and the T-shaped groove 205 to drive the displacement blocks 202 on both sides to move away from each other, that is, to drive the clamping block 1 to move towards the limiting block 2, so as to jointly clamp the thin-walled casting 100.

[0038] The implementation principle of Example 1 is as follows: By defining the rigid clamping area 12 and using the silicone layer as the semi-rigid clamping area 11, under high clamping force, the rigid clamping area 12 can stably clamp the thick-walled, high-rigidity part of the thin-walled casting 100 through conformal contact. By limiting the thickness and hardness of the silicone layer, the semi-rigid clamping area 11 has a certain compressibility and rigidity. First, the silicone layer can deform itself to conform to the outer surface of the thin-walled tube 200 of the thin-walled casting 100, resulting in a more balanced distribution of clamping force and reducing stress concentration caused by local hard extrusion, which could lead to the ellipticing of the thin-walled tube 200. Second, the increase in the compressive reaction force of the silicone layer is more gradual than the increase in the clamping force of the rigid clamping area 12, that is, the clamping force on the thin-walled tube 200 is limited to a certain range and will not increase linearly with the total clamping force of the clamping block 1 or the limiting block 2.

[0039] In summary, by using the rigid clamping area 12 and the semi-rigid clamping area 11 to perform contour clamping, the clamping stability of the thin-walled casting 100 is comprehensively improved and the degree of clamping deformation of the thin-walled casting 100 is reduced, thereby improving the machining accuracy.

[0040] Example 2 differs from Example 1 in that, as Figure 4 , Figure 5 As shown, the clamping block 1 includes a first block 13, a first clamping member 15, a first locking block 16, and a first bolt 17. The first block 13 has a rigid clamping area 12. The first block 13 is fixed to the displacement block 202 of the bidirectional clamping mechanism 20, that is, the first block 13 is slidably connected to the tooling body 10. The first block 13 has a first guide groove 14. The first clamping member 15 is a single-block structure. The first clamping member 15 is slidably engaged with the first guide groove 14. One side of the first clamping member 15 is a semi-rigid clamping area 11, and the other side of the first clamping member 15 is a second inclined surface 150.

[0041] The first locking block 16 and the first guide groove 14 slide and engage in a direction perpendicular to the tooling body 10. The first locking block 16 has a first inclined surface 161, which engages with the second inclined surface 150.

[0042] The first bolt 17 is used to limit the sliding position of the first locking block 16. Specifically, the first bolt 17 passes through the first locking block 16, the first bolt 17 is threadedly connected to the first block 13, and the head of the first bolt 17 abuts against the upper surface of the first locking block 16.

[0043] The limiting block 2 includes a second block 21, a second clamping member 22, a second locking block 23, and a second bolt 25. The second block 21 has a rigid clamping area 12. The second block 21 is fixedly connected to the tooling body 10. The second block 21 has a second guide groove 24. The second clamping member 22 is a single-piece structure. The second clamping member 22 slides and engages with the second guide groove 24. One side of the second clamping member 22 is a semi-rigid clamping area 11, and the other side of the second clamping member 22 is a fourth inclined surface 220.

[0044] The second locking block 23 and the second guide groove 24 slide and cooperate in the direction perpendicular to the tooling body 10. The second locking block 23 has a third inclined surface 231, which is fitted and cooperates with the fourth inclined surface 220.

[0045] The second bolt 25 is used to limit the sliding position of the second locking block 23. Specifically, the second bolt 25 passes through the second locking block 23, the second bolt 25 is threadedly connected to the second block 21, and the head of the second bolt 25 abuts against the upper surface of the second locking block 23.

[0046] The implementation principle of Example 2 is as follows: The bidirectional clamping mechanism 20 drives the clamping block 1 to move toward the limiting block 2, that is, the first block 13 moves toward the second block 21. The rigid clamping area 12 of the first block 13 and the rigid clamping area 12 of the second block 21 jointly clamp the thick-walled part of the thin-walled casting 100. At this time, the clamping force is mainly controlled by the fastening bolt 203. Since the thick-walled part is not easy to be deformed by clamping, the clamping force can be set to be larger to improve the clamping stability. Then, the first bolt 17 and the second bolt 25 are rotated respectively. The first locking block 16 moves down and the second locking block 23 moves down to drive the semi-rigid clamping area 11 of the first clamping member 15 and the semi-rigid clamping area 11 of the second clamping member 22 to jointly clamp the thin-walled tube 200 of the thin-walled casting 100. At this time, the clamping force is controlled by the first bolt 17 and the second bolt 25. Therefore, the clamping force can be set to be smaller or moderate to improve the clamping stability without deforming the thin-walled tube 200.

[0047] That is, by independently displacing the rigid clamping area 12 and the semi-rigid clamping area 11, the clamping force of the rigid clamping area 12 and the semi-rigid clamping area 11 can be selectively set, so as to comprehensively improve the clamping stability of the thin-walled casting 100 and reduce the degree of clamping deformation of the thin-walled tube 200, thereby improving the machining accuracy.

[0048] Example 3 differs from Example 2 in that, as Figure 6 , Figure 7 As shown, the first clamping member 15 includes a first central clamping block 151 and two first side clamping blocks 152. The two second side clamping blocks 222 are located on both sides of the first central clamping block 151 along the width direction of the tooling body 10. The upper opening of the first guide groove 14 is trapezoidal. The first central clamping block 151 is slidably connected to the bottom wall of the first guide groove 14. The specific structure of this sliding connection can be a T-shaped sliding structure to ensure that the sliding does not come out. The sliding direction of the first central clamping block 151 is the length direction of the tooling body 10.

[0049] The first side clamping block 152 is slidably connected to the side groove wall of the first guide groove 14. The specific structure of this sliding connection can be a T-shaped sliding structure to ensure that the sliding does not come out. The sliding direction of the first side clamping block 152 is the radial direction of the thin-walled tube body 200 of the thin-walled casting 100.

[0050] like Figure 7 , Figure 8As shown, one side of the first middle clamping block 151 and the two first side clamping blocks 152 are all semi-rigid clamping areas 11, and the other side of the first middle clamping block 151 and the two first side clamping blocks 152 are all second inclined surfaces 150. That is, there are three second inclined surfaces 150, and they are not coplanar. Therefore, the first inclined surface 161 of the first locking block 16 is also adaptively set to three, so as to respectively adapt to the second inclined surfaces 150 of the first middle clamping block 151 and the two first side clamping blocks 152.

[0051] The second clamping member 22 includes a second central clamping block 221 and two second side clamping blocks 222. The two second side clamping blocks 222 are located on both sides of the second central clamping block 221 along the width direction of the tooling body 10. The upper opening of the second guide groove 24 is trapezoidal. The second central clamping block 221 is slidably connected to the bottom wall of the second guide groove 24. The specific structure of this sliding connection can be a T-shaped sliding structure to ensure that the sliding does not come out. The sliding direction of the second central clamping block 221 is the length direction of the tooling body 10.

[0052] The second side clamping block 222 is slidably connected to the side groove wall of the second guide groove 24. The specific structure of this sliding connection can be a T-shaped sliding structure to ensure that the sliding does not come out. The sliding direction of the second side clamping block 222 is the radial direction of the thin-walled tube body 200 of the thin-walled casting 100.

[0053] like Figure 7 , Figure 8 As shown, one side of the second middle clamping block 221 and the two second side clamping blocks 222 are all semi-rigid clamping areas 11, and the other side of the second middle clamping block 221 and the two second side clamping blocks 222 are all fourth inclined surfaces 220. That is, there are three fourth inclined surfaces 220, and they are not coplanar. Therefore, the third inclined surface 231 of the second locking block 23 is also adaptively set to three, so as to respectively adapt to the fourth inclined surfaces 220 of the second middle clamping block 221 and the two second side clamping blocks 222.

[0054] The implementation principle of Example 3 is as follows: When the bidirectional clamping mechanism 20 drives the clamping block 1 to move toward the limiting block 2, the rigid clamping area 12 of the first block 13 and the rigid clamping area 12 of the second block 21 jointly clamp the thick-walled part of the thin-walled casting 100. At this time, a large clamping force is used to improve the clamping stability. Then, the first bolt 17 and the second bolt 25 are rotated respectively, the first locking block 16 moves down, and the second locking block 23 moves down. Taking the first clamping member 15 as an example, the three first inclined surfaces 161 of the first locking block 16 are respectively connected with the second inclined surfaces 150 of the first middle clamping block 151 and the two first side clamping blocks 152, so as to drive the semi-rigid clamping areas 11 of the first middle clamping block 151 and the two first side clamping blocks 152 to press against the outer surface of the thin-walled tube 200 along three different radial directions of the thin-walled tube 200.

[0055] In this way, since the clamping force is controlled by the first bolt 17 and the second bolt 25, the clamping force can be set to be small or moderate, thereby improving the clamping stability without deforming the thin-walled tube 200.

[0056] Secondly, compared to Embodiment 2, by limiting the direction of the clamping force, the first middle clamping block 151, the two first side clamping blocks 152, the second middle clamping block 221, and the two second side clamping blocks 222 clamp symmetrically, making the clamping force on the thin-walled tube 200 more stable, stronger, and less prone to clamping deformation.

[0057] Secondly, since the connection between the thin-walled tube 200 and the thick-walled part has high resistance to deformation, while the position of the thin-walled tube 200 away from the thick-walled part has low resistance to deformation, the clamping force of the semi-rigid clamping area 11 at different positions can be further distinguished to comprehensively improve the clamping stability of the thin-walled tube 200 and reduce the degree of clamping deformation of the thin-walled tube 200, thereby improving the processing accuracy.

[0058] To make the clamping force of the first side clamping block 152 and the second side clamping block 222 greater than that of the first middle clamping block 151 and the second middle clamping block 221, the following settings can be made: the thickness of the silicone layer of the first middle clamping block 151 is greater than the thickness of the silicone layer of the first side clamping block 152, and the thickness of the silicone layer of the second middle clamping block 221 is greater than the thickness of the silicone layer of the second side clamping block 222.

[0059] Alternatively, in other embodiments, the second inclined surface 150 of the first middle clamping block 151 is more inclined than the second inclined surface 150 of the first side clamping block 152, and the fourth inclined surface 220 of the second middle clamping block 221 is more inclined than the fourth inclined surface 220 of the second side clamping block 222. That is, the equivalent downward displacement of the first locking block 16 and the second locking block 23 is converted into the horizontal displacement of the middle clamping block being less than the horizontal displacement of the side clamping block, so that the clamping force of the middle clamping block is less than the clamping force of the side clamping block.

[0060] Example 4 differs from Example 3 in that, as Figure 9 and Figure 10As shown, the first clamping block 151 is elastically connected to the first side clamping block 152, and the second clamping block 221 is elastically connected to the second side clamping block 222. Specifically, the first clamping block 151 has T-shaped mounting grooves 18 vertically penetrating on both sides, and vertical strips 181 are fixed in the mounting grooves 18. Multiple elastic strips 182 are integrally formed on one side of the vertical strips 181. One end of the elastic strips 182 is movably inserted into the slots 183 on the side of the first side clamping block 152. Similarly, the second clamping block 221 also has T-shaped mounting grooves 18 vertically penetrating on both sides, and vertical strips 181 are also fixed in the mounting grooves 18. One end of the elastic strips 182 of the vertical strips 181 is movably inserted into the slots 183 on the side of the second side clamping block 222. In the initial state, when the first middle clamping block 151 and the first side clamping block 152 are not in contact with the thin-walled tube 200, the first side clamping block 152 is closer to the thin-walled tube 200 than the first middle clamping block 151. Similarly, when the second middle clamping block 221 and the second side clamping block 222 are not in contact with the thin-walled tube 200, the second side clamping block 222 is closer to the thin-walled tube 200 than the second middle clamping block 221.

[0061] like Figure 10 , Figure 11 As shown, the first clamping block 151 has a sixth inclined surface 153, which is located below the second inclined surface 150. The inclination angle of the sixth inclined surface 153 is smaller than that of the second inclined surface 150. The sixth inclined surface 153 is also provided with a first clearance groove 154 to avoid the first bolt 17 and the traction rope 32.

[0062] A first pilot block 30 is slidably connected in the first guide groove 14 along the direction perpendicular to the tooling body 10. The first pilot block 30 has a fifth inclined surface 301. The fifth inclined surface 301 of the first pilot block 30 fits with the sixth inclined surface 153. The first pilot block 30 is also provided with a first clearance hole (not shown in the figure) to avoid the first bolt 17.

[0063] like Figure 10 , Figure 11 As shown, the second clamping block 221 has an eighth inclined surface 223, which is located below the fourth inclined surface 220. The inclination angle of the eighth inclined surface 223 is smaller than that of the fourth inclined surface 220. The eighth inclined surface 223 is also provided with a second clearance groove 224 to avoid the second bolt 25 and the traction rope 32.

[0064] A second pilot block 31 is slidably connected in the second guide groove 24 along the direction perpendicular to the tooling body 10. The second pilot block 31 has a seventh inclined surface 311, which fits with the eighth inclined surface 223. The second pilot block 31 is also provided with a second clearance hole to avoid the second bolt 25.

[0065] like Figure 11As shown, the four-axis machining fixture for the thin-walled casting of the solenoid valve also includes an adaptive force-equalizing pre-clamping structure. This structure applies the same downward pulling force to both the first pilot block 30 and the second pilot block 31 simultaneously. The first pilot block 30 drives the first middle clamping block 151 to move towards the thin-walled tube body 200. Due to the elastic connection, the first middle clamping block 151 also synchronously drives the first side clamping block 152 to move towards the thin-walled tube body 200. Because the initial positions of the first middle clamping block 151 and the second side clamping block 222 are different, during this process, the first side clamping block 152 moves to the abutment position before the first middle clamping block 151 (see...). Figure 11 Then the first pilot block 30 continues to move downwards, and the first middle clamping block 151 continues to advance to abut against the thin-walled tube body 200 of the thin-walled casting 100 (see...). Figure 12 During this process, the elastic strip 182 stores force, making the clamping force of the first side clamping block 152 greater than the clamping force of the first middle clamping block 151; the displacement and clamping force application principles of the second pioneer block 31, the second middle clamping block 221 and the second side clamping block 222 are the same as above, and will not be repeated here. This step is the displacement to position and the initial clamping.

[0066] Finally, the first locking block 16 and the second locking block 23 are placed respectively, so that the first locking block 16 and the second locking block 23 are in contact with the first clamping member 15 and the second clamping member 22 respectively. Since the first clamping member 15 and the second clamping member 22 are already in the state of abutting against the thin-walled tube 200, it is only necessary to rotate the first bolt 17 and the second bolt 25 a little half a turn or a few turns to apply the final clamping force.

[0067] In this way, through the adaptive force-equalizing pre-clamping structure, the first clamping member 15 and the second clamping member 22 move synchronously to the positioning state, ensuring precise positioning. Furthermore, the clamping force on the thin-walled tube 200 is adaptively balanced, resulting in precise initial clamping force. Additionally, due to the stored force of the elastic strip 182, the clamping force in the semi-rigid clamping areas 11 at different positions is differentiated. Based on this, the number of turns the first bolt 17 and the second bolt 25 are tightened determines the final clamping force applied to the first locking block 16 and the second locking block 23. This means the final clamping force is applied more precisely and controllably, reducing over- or under-pressure, thereby improving clamping precision, reducing clamping deformation, and enhancing clamping stability.

[0068] The clamping forces of the semi-rigid clamping areas 11 at different positions can be further differentiated to comprehensively improve the clamping stability of the thin-walled tube 200 and reduce the degree of clamping deformation of the thin-walled tube 200, thereby improving the processing accuracy. For example, the silicone layer thickness of the first clamping block 151 is greater than the silicone layer thickness of the first side clamping block 152, and the silicone layer thickness of the second clamping block 221 is greater than the silicone layer thickness of the second side clamping block 222. Alternatively, in other embodiments, the second inclined surface 150 of the first clamping block 151 is more inclined than the second inclined surface 150 of the first side clamping block 152, and the fourth inclined surface 220 of the second clamping block 221 is more inclined than the fourth inclined surface 220 of the second side clamping block 222.

[0069] like Figure 11 As shown, the adaptive force equalization pre-clamping structure includes a traction rope 32, a steel ball 35, a slide bar 34, a first guide wheel 36, a second guide wheel 37, and a drive rod 33. The first guide wheel 36 is located below the first block 13 and is fixed relative to the first block 13 by a support rod 361. The second guide wheel 37 is located below the second block 21 and is fixed to the tooling body 10.

[0070] The bottom of the tooling body 10 is vertically provided with a sliding groove 102. The length direction of the slide bar 34 is the length direction of the tooling body 10. The slide bar 34 has a slide rail groove 341 arranged along its own length direction. The slide bar 34 slides and engages with the slide groove 102 in a direction perpendicular to the tooling body 10. The steel ball 35 slides and engages with the slide rail groove 341, that is, the steel ball 35 can slide horizontally. The steel ball 35 has an annular groove 351. The steel ball 35 is higher than the first guide wheel 36 and is located in the middle position between the first guide wheel 36 and the second guide wheel 37.

[0071] The traction rope 32 can be made of tensile deformation-resistant materials such as F-12 aramid fiber, ultra-high molecular weight polyethylene fiber, para-aramid, polybenzobisoxazole fiber, and polyoxymethylene fiber. One end of the traction rope 32 is fixed to the first pilot block 30, and the other end of the traction rope 32 extends downward and around the first guide wheel 36, extends upward at an angle and around the annular groove 351 of the steel ball 35, extends downward at an angle and around the second guide wheel 37, and extends upward and is fixed to the second pilot block 31.

[0072] The drive rod 33 has a sliding section 331 and a threaded section 332. The drive rod 33 can slide vertically relative to the tooling body 10, and the drive rod 33 can also be threadedly fixed to the tooling body 10. The upper end of the drive rod 33 abuts against the bottom of the slide bar 34.

[0073] The working steps of the adaptive uniform force pre-clamping structure are as follows: After the clamping block 1 moves toward the limiting block 2 and the rigid clamping area 12 clamps the thin-walled casting 100, the drive rod 33 pushes the slide bar 34 upward to drive the steel ball 35 to move upward, thereby tightening the traction rope 32, which in turn drives the first pioneer block 30 and the second pioneer block 31 to move downward, thereby completing the displacement and initial clamping of the first clamping member 15 and the second clamping member 22. At this time, the drive rod 33 is threadedly fixed to the tooling body 10, and the traction rope 32 remains taut. The tight state ensures that the first clamping member 15 and the second clamping member 22 remain in their abutting position, making them more stable and facilitating the application of the final clamping force. Secondly, since the steel ball 35 can slide horizontally, that is, according to the change in tension at both ends of the traction rope 32, the steel ball 35 can adaptively move horizontally to keep the tension at both ends of the traction rope 32 consistent, that is, to ensure that the thin-walled tube 200 is subjected to the same initial clamping force from the first clamping member 15 and the second clamping member 22 respectively, and is in a stable abutting state.

[0074] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A four-axis machining fixture for thin-walled castings of electromagnetic valves, characterized in that: The tooling includes a main body (10), a bidirectional clamping mechanism (20), and a limiting block (2). The bidirectional clamping mechanism (20) has clamping blocks (1) fixed on both sides. The bidirectional clamping mechanism (20) is used to drive the clamping blocks (1) to move towards or away from the limiting block (2). The opposing surfaces of the clamping blocks (1) and the limiting block (2) are both set as contoured surfaces. The contoured surfaces include a rigid clamping area (12) and a semi-rigid clamping area (11). The semi-rigid clamping area (11) is covered with a silicone layer. The thickness of the silicone layer is 1.8-2.0 mm, and the hardness of the silicone layer is Shore hardness 45A-50A.

2. The four-axis machining fixture for the thin-walled casting of the solenoid valve according to claim 1, characterized in that: The bidirectional clamping mechanism (20) is configured as two and is arranged at intervals along the length of the tooling body (10).

3. The four-axis machining fixture for the thin-walled casting of the solenoid valve according to claim 1, characterized in that: The bidirectional clamping mechanism (20) includes a fastening bolt (203), a control block (201), and two displacement blocks (202). The control block (201) has inclined T-shaped blocks (204) on both sides. The displacement blocks (202) are slidably connected to the tooling body (10) along the length of the tooling body (10). The side of the displacement block (202) has an inclined T-shaped groove (205). The T-shaped blocks (204) and the T-shaped grooves (205) slide together. The fastening bolt (203) is vertically inserted through the first control block (201). The fastening bolt (203) is threadedly connected to the tooling body (10). The displacement blocks (202) are fixedly connected to the clamping block (1).

4. The four-axis machining fixture for the thin-walled casting of the solenoid valve according to claim 3, characterized in that: The tooling body (10) has a support platform (101) protruding from one surface. The displacement block (202) is slidably connected to the support platform (101) along the length direction of the tooling body (10). The limiting block (2) is fixed to the support platform (101).

5. The four-axis machining fixture for the thin-walled casting of the solenoid valve according to claim 4, characterized in that: The support platform (101) is elongated.

6. The four-axis machining fixture for the thin-walled casting of the solenoid valve according to claim 1, characterized in that: The clamping block (1) includes a first block (13), a first clamping member (15), a first locking block (16), and a first bolt (17). The first block (13) has the rigid clamping area (12) and is fixed to the bidirectional clamping mechanism (20). The first clamping member (15) has the semi-rigid clamping area (11) and slides with the first block (13). The first locking block (16) slides with the first block (13) in a direction perpendicular to the tooling body (10). The first bolt (17) is used to limit the sliding position of the first locking block (16). The first locking block (16) has a first inclined surface (161), and the first clamping member (15) has a component that matches the first inclined surface (161). The second inclined surface (150) of the limiting block (2) includes a second block (21), a second clamping member (22), a second locking block (23), and a second bolt (25). The second block (21) is fixed to the bidirectional clamping mechanism (20). The second block (21) has the semi-rigid clamping area (11). The second clamping member (22) slides with the second block (21). The second locking block (23) slides with the second block (21) in a direction perpendicular to the tooling body (10). The second bolt (25) is used to limit the sliding position of the second locking block (23). The second locking block (23) has a third inclined surface (231). The second clamping member (22) has a fourth inclined surface (220) that cooperates with the third inclined surface (231).

7. The four-axis machining fixture for the thin-walled casting of the solenoid valve according to claim 6, characterized in that: The first clamping member (15) includes a first central clamping block (151) and two first side clamping blocks (152). The sliding direction of the first central clamping block (151) is the length direction of the tooling body (10), and the sliding direction of the first side clamping blocks (152) is the radial direction of the thin-walled tube body (200) of the thin-walled casting (100). One side of the first central clamping block (151) and the two first side clamping blocks (152) are the semi-rigid clamping area (11), and the other side of the first central clamping block (151) and the two first side clamping blocks (152) are the second inclined surface (150). The second clamping member (22) includes a second central clamping block (221) and two second side clamping blocks (222). The sliding direction of the second central clamping block (221) is the length direction of the tooling body (10), and the sliding direction of the second side clamping blocks (222) is the radial direction of the thin-walled tube body (200) of the thin-walled casting (100). One side of the second central clamping block (221) and the two second side clamping blocks (222) are the semi-rigid clamping area (11), and the other side of the second central clamping block (221) and the two second side clamping blocks (222) are the fourth inclined surface (220).

8. The four-axis machining fixture for the thin-walled casting of the solenoid valve according to claim 7, characterized in that: It also includes an adaptive force-equalizing pre-clamping structure. The first block (13) is slidably connected to a first pioneer block (30) in a direction perpendicular to the tooling body (10). The first pioneer block (30) has a fifth inclined surface (301). The first middle clamping block (151) has a sixth inclined surface (153) that cooperates with the fifth inclined surface (301). The inclination angle of the sixth inclined surface (153) is smaller than that of the second inclined surface (150). The second block (21) is slidably connected to a second pioneer block (31) in a direction perpendicular to the tooling body (10). The second pioneer block (31) has a seventh inclined surface (311). The second middle clamping block (221) has an eighth inclined surface (223) that cooperates with the seventh inclined surface (311). The inclination angle of the eighth inclined surface (223) is smaller than that of the fourth inclined surface. Surface (220); the first middle clamping block (151) is elastically connected to the first side clamping block (152), and the second middle clamping block (221) is elastically connected to the second side clamping block (222); the adaptive uniform force pre-clamping structure is used to simultaneously apply the same downward force to the first pioneer block (30) and the second pioneer block (31) so that the first middle clamping block (151), the first side clamping block (152), the second middle clamping block (221), and the second side clamping block (222) move to the outer peripheral surface of the thin-walled tube body (200) of the thin-walled casting (100), and in this process, the first side clamping block (152) moves to the abutment position before the first middle clamping block (151), and the second side clamping block (222) moves to the abutment position before the second middle clamping block (221).

9. The four-axis machining fixture for the thin-walled casting of the solenoid valve according to claim 8, characterized in that: The adaptive force equalization pre-clamping structure includes a traction rope (32), a steel ball (35), a slide bar (34), a first guide wheel (36), a second guide wheel (37), and a drive rod (33). The first guide wheel (36) is located below the first block (13) and is fixed relative to the first block (13). The second guide wheel (37) is located below the second block (21) and is fixed relative to the second block (21). The bottom of the tooling body (10) is vertically provided with a slide groove (102). The length direction of the slide bar (34) is the length direction of the tooling body (10). The slide bar (34) has a slide rail groove (341) arranged along its own length direction. The slide bar (34) slides and engages with the slide groove (102) in a direction perpendicular to the tooling body (10). The steel ball (35) engages with the slide rail groove (341). The steel ball (35) has an annular groove (351) and is higher than the first guide wheel (36) and located in the middle of the first guide wheel (36) and the second guide wheel (37). One end of the traction rope (32) is fixed to the first pilot block (30), and the other end of the traction rope (32) extends downward and around the first guide wheel (36), extends upward at an angle and around the annular groove (351) of the steel ball (35), extends downward at an angle and around the second guide wheel (37), and extends upward and is fixed to the second pilot block (31). The drive rod (33) has a sliding section (331) and a threaded section (332). The drive rod (33) is threadedly connected to the tooling body (10). The end of the drive rod (33) abuts against the bottom of the slide bar (34). The drive rod (33) is used to lift the slide bar (34).

10. The four-axis machining fixture for the thin-walled casting of the solenoid valve according to claim 7, characterized in that: The silicone layer thickness of the first middle clamping block (151) is greater than that of the first side clamping block (152), and the silicone layer thickness of the second middle clamping block (221) is greater than that of the second side clamping block (222).

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