A ball valve core surface machining and fixing device

Abstract

This invention provides a ball valve core surface machining and fixing device. Through the precise design and synergistic action of the reference rotating block and the locking block, it provides accurate positioning and stable support for the ball valve core, ensuring that the core maintains the correct position and shape during machining. The eccentric locking hole design solves the problem of misalignment between the product's arc surface and the reserved clamping position, greatly improving surface quality and reducing machining steps and costs. The pull-back clamping handle achieves pull-back clamping through an internal locking screw, which cooperates with the tailstock pin to fix the product, making installation and disassembly simple and quick. After machining, the product can be easily removed simply by loosening the pull-back clamp and tailstock pin, without the need for complex operations and tools, greatly saving installation and disassembly time, improving machining efficiency, and making it suitable for mass production.

Description

Technical Field

[0001] This utility model relates to the field of valve processing technology, specifically to a ball valve core surface processing and fixing device. Background Technology

[0002] In the machining of components related to coolant piping in new energy vehicle batteries, the batch precision machining of the core spherical surface of ball valves is crucial. This technology primarily focuses on this machining scenario, and is particularly suitable for lathe machining environments with extremely high requirements for precision and efficiency.

[0003] The core of a ball valve is an irregularly shaped component, and its special structure makes it difficult to directly and effectively process it using a lathe. To achieve the required precision and surface roughness standards, a high-precision machining center is usually required.

[0004] Currently, the existing processing method involves first creating the circular surface of the valve core using a conventional machining center, then machining the arc surface at a relatively slow speed, and finally grinding the surface after machining. However, this processing method has significant drawbacks and is extremely inefficient. On the one hand, the machining center is slow when machining the arc surface alone; on the other hand, the installation and disassembly process is complex, which not only increases processing costs but also makes this method difficult to gain an advantage in market competition.

[0005] For example, a ball surface grinding device for ball valve processing (patent number CN201921516935X) relates to the field of valve processing. This ball surface grinding device includes a grinding box with a grinding groove on its upper surface. Support mechanisms are fixedly installed at both ends of the inner bottom wall of the grinding groove. Each support mechanism includes a support rod, the bottom end of which is fixedly installed on the inner wall of the grinding box. A sliding groove is formed on the surface of the support rod, and a compression spring is fixedly connected inside the groove. A semi-circular sleeve is fixedly installed at the top of the compression spring. A rotating shaft is rotatably connected between the semi-circular sleeve and the inner wall of the groove. A rotating sleeve is fixedly fitted onto the outer surface of the rotating shaft. However, this technical solution relies solely on the compression spring for support. During grinding, the ball may wobble due to the grinding force. Especially during high-precision grinding, this wobble can lead to uneven grinding of the ball surface, resulting in scratches, unevenness, and other defects, affecting the quality and performance of the ball valve. Utility Model Content

[0006] In view of the shortcomings of the prior art, the purpose of this utility model is to provide a ball valve core surface machining and fixing device.

[0007] To achieve the above objectives, this utility model provides the following technical solution: a ball valve core surface machining and fixing device, comprising, A reference rotary block has a locking block embedded on its flat surface for tooling positioning. One end of the flat surface of the reference rotary block has a positioning opening, and the other end has an arc-shaped locking groove. The locking block has a through-hole for positioning; The pull-back clamping handle is installed at one end of the reference rotary block where an arc-shaped slot is provided, and an assembly gap is left between the handle and the arc-shaped slot. An eccentric locking hole is provided through the extension direction of the pull-back clamping handle and is located in the same horizontal extension plane as the slot and the positioning hole, wherein the central axis of the eccentric locking hole is offset from the central axis of the positioning hole. Positioning bolts are inserted into the eccentric locking holes and the inside of the reference rotating block, respectively, and the fixture is fixed by threaded connection. The reference rotary block and the locking block constrain the workpiece from different positions, so that the side of the workpiece and the corresponding contact surfaces of the reference rotary block and the locking block together form a complete circle.

[0008] As a preferred embodiment of this application, the reference rotary block is obtained by vertically cutting a cylinder into its original shape along a vertical reference line.

[0009] As a preferred embodiment of this application, the reference rotary block and the locking block are integrally formed, wherein the locking block is configured with an arc surface on only one side, and the arc surface is closely fitted with the arc surface of the reference rotary block and the arc surface and the arc surface are the same circle.

[0010] As a preferred embodiment of this application, the locking block is provided with symmetrical locking angle slopes on the side facing away from the reference rotating block, and the locking angle slopes are connected by a horizontal plane and adjacent to the arc surface (wherein the horizontal plane is parallel to the plane of the reference rotating block).

[0011] Furthermore, the positioning opening extends vertically along the end wall of the beveled corner of the locking block (the direction of the positioning opening is perpendicular to the horizontal plane), into the reference rotating block, and forms an L-shaped opening groove. The positioning opening is connected to the positioning hole.

[0012] Furthermore, the side of the locking block opposite to the arc surface and the side opposite to the positioning opening are both set as vertical surfaces (the vertical surfaces are L-shaped), and a gap is left between the vertical surfaces and the wall end of the reference rotary block that is closest to the corresponding horizontal distance.

[0013] Furthermore, with the vertical plane as a reference, the inclination angle of the angled surface is 30-60°.

[0014] Furthermore, within the same horizontal plane, the radius of the same reference circle of the reference rotating block and the locking block: the vertical height of the reference rotating block: the depth of the positioning opening slot: the vertical height of the locking block = 1:0.6-1.1:0.5-0.7:0.3-0.4.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows: With high positioning accuracy, the reference rotary block has a locking block embedded in its plane, with a positioning opening at one end and an arc-shaped groove at the other, providing a multi-dimensional and precise reference for tooling positioning. The positioning hole through the locking block, the eccentric locking hole of the pull-back clamping handle, and the arc-shaped groove are all on the same horizontal extension plane, through which the positioning bolt passes to fix the tooling. The precise positional relationship of each component greatly improves the accuracy of workpiece positioning during machining and ensures the dimensional accuracy of the ball valve core surface.

[0016] The clamping mechanism is stable and reliable. The pull-back clamping handle is installed at the end of the reference rotary block and has an assembly gap with the arc-shaped slot. Combined with the offset design of the eccentric locking hole and the positioning hole, as well as the threaded connection of the positioning bolt, a robust clamping structure is formed. This design can effectively resist various external forces during the machining process, ensuring that the workpiece remains in a fixed position during machining and will not be displaced due to vibration or other factors, thus guaranteeing the stability and continuity of machining.

[0017] Adapted for circular machining, the reference rotary block and locking block constrain the workpiece from different positions, ensuring that the side of the workpiece and its corresponding contact surfaces form a complete circle. This design perfectly suits the circular structure of the ball valve core, providing an ideal machining environment and shape reference for the ball valve core surface machining. This helps improve the surface machining quality of the ball valve core, achieving higher levels of surface accuracy and roundness. Attached Figure Description

[0018] Other features, objects, and advantages of this invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is an assembly drawing of the workpiece formed by the present invention. Figure 2 This is a schematic diagram of the explosion state of this utility model; Figure 3 This is a schematic diagram of the explosion state of this utility model from another angle; Figure 4 This is a top view of the present invention; Figure 5 for Figure 4 Sectional view of AA.

[0019] In the diagram: 1. Reference rotary block; 11. Positioning opening; 12. Arc-shaped groove; 2. Locking block; 21. Positioning hole; 22. Arc surface; 23. Clamping angle bevel; 24. Vertical surface; 3. Rear pull clamping handle; 31. Eccentric clamping hole; 4. Positioning bolt. Detailed Implementation

[0020] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.

[0021] like Figure 1-5 As shown, this application provides a ball valve core surface machining and fixing device, including, The reference rotary block 1 has a locking block 2 embedded on its plane (taking the horizontal plane with the x-axis as the reference as shown in the figure) for tooling positioning. One end of the plane of the reference rotary block 1 has a positioning opening 11, and the other end has an arc-shaped groove 12. The locking block 2 has a positioning hole 21 through it; The pull-back clamping handle 3 is installed at one end of the reference rotary block 1 where the arc-shaped slot 12 is provided, and an assembly gap is left between it and the arc-shaped slot 12; An eccentric locking hole 31 is provided through the extension direction of the pull-back clamping handle 3 and is located in the same horizontal extension plane as the slot and the positioning hole 21. The central axis of the eccentric locking hole 31 is offset from the central axis of the positioning hole 21 (there is a gap between them on the same y-axis extension line). Positioning bolts 4 are respectively inserted into the eccentric locking hole 31 and the reference rotating block 1, and are used to fix the fixture by threaded connection. The reference rotating block 1 and the locking block 2 constrain the workpiece from different positions, so that the side of the workpiece and the corresponding contact surfaces of the reference rotating block 1 and the locking block 2 together form a complete circle.

[0022] Implementation principle: The plane of the reference rotary block 1 and the locking block 2 are fitted together, with a positioning opening 11 at one end and an arc-shaped groove 12 at the other end providing initial positioning of the valve core from different directions. The positioning hole 21 of the locking block 2 is connected to the eccentric locking hole 31 and the interior of the reference rotary block 1 by positioning bolts 4, forming a stable clamping mechanism. The pull-back clamping handle 3 is installed at one end of the reference rotary block 1, leaving an assembly gap with the arc-shaped groove 12. Through the pull-back action and the engagement of the ejector pin, the valve core is firmly fixed in the machining position. At the same time, the contact surface of the reference rotary block 1 and the locking block 2 forms a complete circle with the side of the valve core, providing a precise reference for lathe machining.

[0023] The beveled surface 23 of the retaining block 2 fits against the reserved clamping surface at the end of the valve core, providing axial positioning; The arc-shaped groove 12 of the reference rotary block 1 contacts the arc surface 22 of the valve core, forming radial support; The threaded locking of the eccentric locking hole 31 and the positioning bolt 4 generates a "pull-back force", which pulls the valve core toward the composite reference surface of the locking block 2 and the reference rotating block 1, eliminating the assembly gap.

[0024] The reference rotary block 1 is obtained by cutting a cylinder vertically along a reference line. The cut plane is used as the installation reference plane and is coplanar with the plane of the clamping block 2 to ensure the parallelism between the valve core axis and the machine tool spindle axis after eccentric adjustment. The remaining cylindrical arc surface is used as a dynamic balance counterweight to counteract the centrifugal force caused by eccentric clamping.

[0025] The principle of this design is to use a cylinder as the original shape and cut it vertically along the baseline in the vertical direction (horizontally extending the x-axis). After this cutting, the reference rotating block 1 retains a part of the cylindrical arc surface 22, which can provide circumferential positioning and support for the valve core. At the same time, the cut plane facilitates the installation of the locking block 2 and other components, making the entire device structure compact and reasonable.

[0026] The reference rotary block 1 and the clamping block 2 are integrally formed. The clamping block 2 has only one side with an arc surface 22. The arc surface 22 is in close contact with the arc surface of the reference rotary block 1, and the arc surface 22 and the arc surface are the same circle. The principle of this design structure is that the clamping block 2 and the reference rotary block 1 together constitute the positioning system of the valve core. The arc surface 22 of the clamping block 2 is in close contact with the side of the valve core, further constraining the position of the valve core and preventing radial displacement during processing (that is, after integral forming, the two arc surfaces 22 are different parts of the same processing reference circle. During lathe processing, the two can be used as a unified rotation reference. The arc surface 22 of the valve core and the arc surface 22 of the fixture form a conjugate contact during rotation, reducing vibration).

[0027] On the side of the locking block 2 facing away from the reference rotating block 1 (the top surface in the example), symmetrical locking angle slopes 23 are provided. The locking angle slopes 23 are connected by a horizontal plane and adjacent to the arc surface 22 (where the horizontal plane is parallel to the plane of the reference rotating block 1). The design principle is to design symmetrical locking angle slopes 23 on the side of the locking block 2 facing away from the reference rotating block 1, with the two slopes connected by a horizontal plane and adjacent to the arc surface 22. When installing the valve core, the valve core slides in along the locking angle slopes 23 and finally contacts the arc surface 22 and the horizontal plane, achieving precise positioning. At the same time, this structural design makes the force on the locking block 2 more uniform and increases the structural strength. Its function is to convert the axial locking force of the valve core into a radial self-centering force through the wedge effect of the slopes, compensating for casting size deviations. The principle is that when the locking angle slopes 23 contact the valve core slopes, the axial tension of the pull-back clamping handle 3 can be decomposed into: Normal force perpendicular to the inclined plane (provides friction locking); Radial component pointing towards the center of the arc (automatic correction of valve core position error).

[0028] The positioning opening 11 extends vertically along the end wall of the angled surface 23 through the locking block 2 (the extension direction of the positioning opening 11 is perpendicular to the horizontal plane), and extends into the reference rotating block 1 to form an L-shaped opening groove. The positioning opening 11 connects to the positioning hole 21 to realize the angular positioning of the valve core and prevent the valve core from rotating around its own axis during processing (i.e., the "following rotation" phenomenon).

[0029] The locking block 2 has two vertical surfaces 24 on the side opposite to the arc surface 22 and the side opposite to the positioning opening 11 (i.e., the two adjacent sides of the locking block 2 are vertical surfaces 24, and the vertical surface 24 is a plane parallel to the Z-axis reference plane, and the vertical surface 24 is perpendicular to the plane of the reference rotary block 1). (The vertical surface 24 is arranged in a horizontal L-shape.) A gap is left between the vertical surface 24 and the wall end of the reference rotary block 1 that is closest to it horizontally (the vertical surface 24 is located in the plane of the reference rotary block 1) to avoid... Interference and ease of operation: In actual operation, the arc-shaped opening is adjacent to and perpendicular to the vertical surface 24. The design of the vertical surface 24 provides operating space for the installation, disassembly and adjustment of the device, avoiding interference with other components. At the same time, it is convenient to observe the processing of the valve core. In actual operation, the distance between the vertical surface 24 and the wall end of the reference rotary block 1 forms an error absorption zone. When the valve core size is slightly larger than the theoretical value, the locking block 2 can accommodate the deviation through elastic micro-deformation (due to the flexibility of the pull-back clamping handle 3), avoiding the transfer of stress to the processing surface.

[0030] Based on the self-locking condition of the inclined plane (θ ≤ arctanμ, μ is the coefficient of friction), 30-60° covers most metal-metal friction pairs (μ≈0.15-0.3), ensuring that the valve core remains tight after the pulling clamping force is removed. Therefore, this application uses the vertical plane 24 as a reference, and the inclination angle of the clamping angle inclined plane 23 is 30-60°. Within the range of 30-60°, the inclined plane can generate reliable self-locking (the inclined plane angle is less than the friction angle), while avoiding excessive axial force demand due to the angle being too small.

[0031] To ensure that the centrifugal torque of the fixture and the eccentric torque of the valve core cancel each other out during eccentric rotation, thus reducing wear on the machine tool spindle bearings, the following ratios are established on the same horizontal plane: Radius of the same reference circle of the reference rotary block 1 and the locking block 2: Vertical height of the reference rotary block 1: Groove depth of the positioning opening 11: Vertical height of the locking block 2 = 1:0.6-1.1:0.5-0.7:0.3-0.4. This proportional relationship implies a mass distribution design. The ratio of the reference circle radius to the height (1:0.6-1.1) controls the rotation radius of the fixture to match the eccentricity of the valve core. The ratio of the depth of the positioning opening 11 groove to the height of the retaining block 2 (0.5-0.7:0.3-0.4) ensures that the root of the retaining block 2 has sufficient rigidity, thus avoiding the tremor caused by high-frequency cutting vibration.

[0032] This application uses an irregularly shaped fixture to hold both ends of the valve core, allowing its arc surface 22 to be machined on a lathe. Utilizing the rotary machining characteristics of the machine tool, the arc surface can be machined quickly, achieving the desired surface roughness and precision without subsequent fine grinding. Installation and disassembly are convenient, and machining efficiency is improved.

[0033] Detailed workflow (single item ≤ 45 s) Pre-loaded (10 s) ① Slide the pre-reserved clamping flat square of the valve core casting blank into the horizontal position of the L-shaped positioning opening 11 of the locking block 2; ② The inclined surface at the end of the valve core and the inclined surface 23 of the retaining angle are automatically centered, and the arc surface 22 and the arc surface of the reference rotating block 1 are in conjugate contact → forming a "virtual circle".

[0034] Lock (15 s) ① After the machine tool hydraulic chuck clamps, pull back the clamping handle 3; ② The tailstock hydraulic ejector pin extends and presses against the center hole of the valve core (ejector pin position), generating an axial force of 15-20 kN; ③ The pull-back clamping handle 3 undergoes elastic deformation of 0.05-0.08 mm under axial force, pulling the valve core back by 0.2 mm through the eccentric locking hole 31, thus eliminating all assembly gaps.

[0035] Cutting (variable) ① Spindle speed 400-800 rpm (adjustable according to valve core diameter D=40-100 mm); ② Rough turning with G71 tool → leave 0.1 mm allowance → finish turning with G70 tool in one pass; ③ Cutting parameters: ap=0.3 mm, f=0.15 mm / r, vc=120 m / min; surface roughness Ra 0.6-0.8 μm (actual measurement).

[0036] Release (8 seconds) ① Tailstock ejector pin retracts → chuck loosens → valve core is manually removed; ② Inspection: Roundness ≤ 0.008 mm, diameter tolerance ± 0.01 mm, no precision grinding required.

[0037] Improve machining accuracy Valve core mass m = 1.2 kg, eccentricity e = 4 mm → centrifugal force Fc = mω²e = 1.2 × (2π × 600 / 60)² × 0.004 ≈ 113 N The design of the counterweight for the reference slewing block 1 has a mass mp = 0.35 kg and a radius rp = 15 mm. The balancing force Fp = mpω²rp = 0.35 × ω² × 0.015 ≈ 10³ N. The remaining unbalanced force ΔF = 10 N acts on the spindle bearing, which is less than 1% of the rated dynamic load, and its impact on bearing life is negligible.

[0038] Maintenance and lifespan Wear limit of positioning opening 11: When the opening width wears >0.05 mm, the retaining block 2 can be replaced (modular design, fixed by 2 M8 hexagon socket screws).

[0039] Pull-back clamping handle 3: Every 5000 cycles or 6 months, the contact rate of the conical surface needs to be checked to be ≥85%; otherwise, it should be replaced or ground and repaired.

[0040] Reference rotary block 1: If it is used normally for ≥5 years or 200,000 cycles and radial runout >0.01 mm occurs, it should be returned to the factory for fine grinding.

[0041] Extended Applications Simply replace the retaining block 2 and the eccentric retaining hole 31 bushing to cover it: Valve core diameter range: Ø25-150 mm Eccentricity range: 0-8 mm Interface standardization: All specifications of the pull-back clamp handle 3 are unified as BBT40 / HSK-A63, realizing zero-downtime model changeover.

[0042] The precise design and synergistic action of the reference rotary block 1 and the locking block 2 provide accurate positioning and stable support for the ball valve core, ensuring that the core maintains the correct position and shape during machining. The design of the eccentric clamping hole 31 solves the problem of misalignment between the product's arc surface 22 and the reserved clamping position, enabling accurate machining of the required circular surface and effectively improving machining accuracy. This results in a high level of roundness and dimensional accuracy of the machined ball valve core's arc surface 22.

[0043] Improve surface quality The reference rotary block 1 can counteract vibrations during lathe machining, reducing the impact of vibrations on machining and avoiding surface defects and poor machining caused by vibrations. Therefore, when using this device to machine the arc surface 22 of the ball valve core, a high surface roughness requirement can be achieved without subsequent fine grinding, greatly improving surface quality and reducing machining steps and costs.

[0044] Easy to install and disassemble, improving processing efficiency The pull-back clamping handle 3 uses an internal locking screw to achieve pull-back clamping, which works in conjunction with the tailstock ejector pin to secure the product. The installation and disassembly process is simple and quick. After processing, the product can be easily removed simply by loosening the pull-back clamping jaws and the tailstock ejector pin, without the need for complicated operations and tools. This greatly saves installation and disassembly time, improves processing efficiency, and is suitable for mass production.

[0045] Highly adaptable This device, through reasonable design and parameter adjustment, can adapt to the processing requirements of ball valve cores of different specifications and models. By selecting appropriate reference models and adjusting the dimensions and positions of various components, it can precisely process ball valve cores of different diameters and shapes, exhibiting strong versatility and adaptability. Overview of Implementation Principles core issues Deficiencies of traditional solutions The principle of this device Scientific basis Machining of eccentric arc surfaces Multiple clamping and coordinate system transformations are required. The eccentric chuck hole establishes the "machining reference circle" in one operation. Eccentricity formula: e = Rr, directly compensated by fixture offset. Maintaining roundness Cantilever clamping causes radial runout >0.05 mm "Dual-pivot" dynamic balancing of reference slewing block and tailstock ejector pin For a two-supported beam, the deflection δ∝L³, with the span halved, the deflection decreases to 1 / 8. Quick Changeover Screw clamping > 5 min Pull back clamp handle + quick-change positioning opening Based on the "3-2-1" positioning principle, the over-constraint is reduced to quasi-static indeterminate. Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this utility model without departing from the spirit and scope of the technical solutions of this utility model, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A device for fixing the surface of a ball valve core, characterized in that, include, A reference rotary block (1) has a locking block (2) embedded on its plane for tooling positioning. The reference rotary block (1) has a positioning opening (11) at one end of its plane and an arc-shaped slot (12) at the other end. The locking block (2) has a positioning hole (21) through it; The pull-back clamping handle (3) is installed on one end of the reference rotary block (1) which has an arc-shaped slot (12), and there is an assembly gap between it and the arc-shaped slot (12); An eccentric locking hole (31) is opened through the extension direction of the pull-back clamping handle (3) and is located in the same horizontal extension plane as the slot and the positioning hole (21), wherein the central axis of the eccentric locking hole (31) is offset from the central axis of the positioning hole (21); Positioning bolts (4) are respectively inserted into the eccentric locking hole (31) and the reference rotating block (1), and the fixture is fixed by threaded connection. The reference rotating block (1) and the locking block (2) constrain the workpiece from different positions, so that the side of the workpiece and the corresponding contact surfaces of the reference rotating block (1) and the locking block (2) together form a complete circle.

2. The ball valve trim surface machining fixture of claim 1, wherein, The reference rotary block (1) is obtained by cutting a cylinder vertically along a reference line in the vertical direction.

3. The ball valve trim surfacing fixture of claim 2, wherein: The reference rotary block (1) and the locking block (2) are integrally formed. The locking block (2) is set with an arc surface (22) on only one side. The arc surface (22) is closely fitted with the arc surface of the reference rotary block (1) and the arc surface (22) and the arc surface are the same circle.

4. The ball valve core surface machining and fixing device as described in claim 3, characterized in that, On the side of the locking block (2) facing away from the reference rotating block (1), there are symmetrical locking angle slopes (23), and the locking angle slopes (23) are connected by a horizontal surface and adjacent to the arc surface (22).

5. The ball valve core surface machining and fixing device as described in claim 4, characterized in that, The positioning opening (11) extends vertically through the end wall of the corner slope (23) of the locking block (2), into the reference rotating block (1), and forms an L-shaped opening groove. The positioning opening (11) is connected to the positioning hole (21).

6. The ball valve core surface machining and fixing device as described in claim 5, characterized in that, The locking block (2) is configured with a vertical surface (24) on the side away from the arc surface (22) and the side away from the positioning opening (11). A gap is left between the vertical surface (24) and the wall end of the reference rotating block (1) that is closest to it in the corresponding horizontal distance.

7. The ball valve core surface machining and fixing device as described in claim 6, characterized in that, Based on the vertical plane (24), the inclination angle of the corner ramp (23) is 30-60°.

8. The ball valve core surface machining and fixing device as described in claim 2, characterized in that, On the same horizontal plane, the radius of the same reference circle of the reference rotating block (1) and the locking block (2): the vertical height of the reference rotating block (1): the groove depth of the positioning opening (11): the vertical height of the locking block (2) = 1:0.6-1.1:0.5-0.7:0.3-0.4.

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