Cathode and tooling for multi-tooth segmented electrolytic machining of large-caliber gun barrel rifling

Abstract

The present invention is a multi-tooth segmented electrolytic machining cathode and tooling for rifling large-caliber artillery barrels, which overcomes the problems of uneven flow field and easy short circuit during the machining process of the electrolytic machining cathode in the prior art, poor cathode forming accuracy, high cost of repeated cathode correction, and long development cycle. It includes a cathode body, on which a segmented cathode copper body with multi-tooth working teeth is designed. The rear guide is set at the tail end of the cathode body, and the front guide is set at the cone end of the cathode body. The intermediate connecting device between the cathode body and the pull rod plays a connecting role. During operation, the cathode body, the pull rod, and the intermediate connecting device rotate and feed together. The inner wall of the segmented cathode copper body on the cathode body is provided with a wedge-shaped positioning keyway. The segmented cathode copper body is fixed in series with a wedge-shaped key, and the multi-tooth working teeth on the segmented cathode copper body have different characteristic parameters, including the negative line angle, the positive line angle, the tooth width, the tooth depth, the wrap angle, etc.

Description

Technical field:

[0001] The invention belongs to the technical field of electrolytic machining, and relates to a cathode and tooling for electrolytic machining of rifling multi-tooth-shaped segmented large-caliber gun barrels. Background technology:

[0002] The traditional processing technology for the rifling of large-caliber artillery barrels is mechanical broaching. To process dozens of riflings, multiple broaches are required, and broaching is performed in groups. After hundreds or thousands of broaching times, the rifling processing can be completed. There are problems of low processing efficiency, high cost, and poor processing quality. In addition, when processing new high-strength and high-hardness artillery barrel materials such as the new generation of ultra-high-strength artillery steel and chromium-based high-temperature alloys, the traditional mechanical broaching process is simply unable to achieve efficient and high-quality processing, and can no longer meet the actual production needs of modern warfare for the rifling of large-caliber artillery barrels such as 105mm and 155mm.

[0003] Electrolytic machining technology is a high-efficiency and high-quality special processing technology that uses the principle of electrochemical anodic dissolution to achieve non-contact small-gap processing under the action of high-speed flowing electrolyte. It is not limited by the strength, hardness, and toughness of metal materials, has the advantages of no tool cathode loss, no residual stress on the workpiece surface, high efficiency, and good surface quality. It is undoubtedly the preferred processing technology for new high-strength and high-hardness artillery barrel materials such as the new generation of ultra-high-strength gun steel and chromium-based high-temperature alloys.

[0004] Since the working teeth and cathode body of the traditional integral electrolytic machining cathode are an integrated structure, based on the principle of electrochemical machining, the electrolytic machining process is easily affected by various factors, such as electric field, magnetic field, flow field and other factors, and even the workpiece material (that is, factors such as uneven workpiece material and impurities), which will lead to machining failure. After the cathode is ablated and damaged during the machining process, the integral electrolytic machining cathode needs to be replaced as a whole, and the workpiece will also be scrapped. At the same time, there are also problems in the electrolytic machining process, such as uneven flow field and easy short circuit, poor cathode forming accuracy, and high cost of repeated cathode correction. These problems undoubtedly increase the production cost and cathode development cycle, and to a certain extent limit the development of electrolytic machining.

[0005] In the existing electrolytic machining process of gun barrel rifling, due to defects in the cathode and tooling structure, the end of the barrel workpiece cannot be precisely formed. For workpieces that cannot be completely precisely formed, the current general solution is to reserve an extra cathode working length at the end of the workpiece and then cut off the reserved part after machining is completed, resulting in waste of barrel material.

[0006] The invention patent "Large-caliber deep mixed rifling duplex cathode and its design method" (application number 201310559158.8) designs the cathode working teeth into a replaceable structure, which solves the problem of traditional cathodes being scrapped due to severe burning of the working teeth during use. However, there are still problems such as excessive number of tests due to the same tooth shape of the cathode working teeth and a long cathode development cycle.

[0007] The invention patent "Spiral electrolytic machining cathode inside the stator of a 200 mm diameter and equal wall thickness screw drill" (application number 201721371435.2) designs the cathode as a structure of rough machining working teeth and fine machining working teeth, avoiding the disadvantage of replacing the entire cathode. However, when the rough machining working teeth and the detachable fine machining working teeth are assembled into a combination, the smooth connection of the tooth surfaces of the two working teeth is overly dependent on the skill level of the assembly workers, resulting in the two being easily misaligned and it is difficult to ensure assembly accuracy, thereby affecting the processing and forming accuracy; at the same time, after the cathode working teeth are damaged and ablated, only the fine machining working teeth can be replaced, which has certain limitations. Summary of the invention:

[0008] The purpose of the present invention is to provide a multi-tooth segmented electrolytic machining cathode and tooling for large-caliber artillery barrel rifling, which overcomes the problems of traditional electrolytic machining cathodes in the prior art, such as uneven flow field and easy short circuit during machining, poor cathode forming accuracy, high cost of repeated cathode correction, and long development cycle.

[0009] Another object of the present invention is to provide a tooling for a large-caliber artillery barrel to solve the problem that the end of the existing large-caliber artillery barrel rifling electrochemical machining workpiece cannot be completely and precisely formed.

[0010] To achieve the above object, the technical solution adopted by the present invention is:

[0011] A multi-tooth segmented electrolytic machining cathode for rifling of a large-caliber artillery barrel is characterized by comprising a cathode body, a segmented cathode copper body with multi-toothed working teeth being provided on the cathode body, a rear guide being provided at the tail end of the cathode body, a front guide being provided at the conical end of the cathode body, an intermediate connecting device being provided between the cathode body and the pull rod, and the cathode body, the pull rod and the intermediate connecting device being rotated and fed together during machining.

[0012] The inner wall of the segmented cathode copper body on the cathode body is provided with a wedge-shaped positioning keyway, and the segmented cathode copper body is fixed in series using a wedge-shaped key, and the multi-toothed working teeth on the segmented cathode copper body have different characteristic parameters, including the negative line angle, the positive line angle, the tooth width, the tooth depth or the winding angle.

[0013] The rear guide of the cathode body is a ring-shaped piece, which is tightened by rotating the prism when being threadedly connected with the cathode body; the workpiece and the outer cylinder of the rear guide are clearance-matched.

[0014] The middle connecting device has the same outer diameter as the pull rod. The internal thread on the left side of the middle connecting device is connected to the external thread of the pull rod. The right side of the middle connecting device has a conical fastening structure, a waterproof gasket and a sealing ring, which cooperate with the limiting threaded holes evenly distributed around the cone end of the cathode body.

[0015] The outer surface of the pull rod is made of insulating material, and the inner material is copper. The pull rod has a double-threaded structure, one end of which is connected to the machine tool spindle through a thread, and the other end is connected to the intermediate connecting device through a thread.

[0016] The cone end of the cathode body and the waterproof gasket end face of the intermediate connecting device are sealed.

[0017] An O-shaped sealing ring and a liquid outlet hole are provided on the front guide of the cathode body.

[0018] The middle connecting device is evenly provided with countersunk screw holes with the same number as the limiting thread holes, and the countersunk screw holes are fastened to the limiting thread holes at the conical end of the cathode body by screws.

[0019] A tooling for a large-caliber artillery barrel is characterized in that a sleeve tooling with the same size as the inner diameter of the gun barrel is provided at the end of the gun barrel workpiece. If the outer diameter of the workpiece is smaller than the aperture at the rear end of the sleeve tooling, a self-tightening steel ring can be mounted on the outer surface of the workpiece and used together with the sleeve tooling. The sleeve tooling is connected to the gun barrel. The sleeve tooling is made of metal and is used in conjunction with a cathode body, an intermediate connecting device, and a pull rod.

[0020] During processing, the cathode body, the pull rod, the intermediate connecting device and the sleeve tooling are coaxial, and after processing is completed, the cathode body is completely inserted into the sleeve tooling.

[0021] Compared with the prior art, the present invention has the following advantages and effects:

[0022] 1. The present invention utilizes a wedge-shaped key to secure segmented cathode copper bodies with multiple tooth shapes in series, ensuring precise installation of the segmented cathode copper bodies without misalignment. This avoids the drawback of modular cathodes being prone to misalignment, which can affect machining accuracy. Furthermore, a single test can be conducted to study the effects of different tooth profiles on rifling machining of large-caliber artillery barrels, significantly reducing the number of tests and cathode development costs. This ensures precise molding of the end of a large-caliber artillery barrel workpiece and improves material utilization.

[0023] 2. The present invention uses a conical structure to tightly connect the cathode and the pull rod, solving the problem of repeated disassembly of the cathode, severe thread wear, and decreased cathode conductivity, which causes the pull rod and cathode to be unable to function normally.

[0024] 3. This invention incorporates a sleeve tooling with the same inner diameter as the gun barrel at the end of the large-caliber gun barrel to be machined. This sleeve connects the barrel to the end of the workpiece, resolving the existing issues of large-caliber gun barrel rifling electrochemical machining, which hinder precision forming and significant material waste. This eliminates the need for material removal at the end of the large-caliber gun barrel, significantly reducing labor costs and saving a significant amount of gun steel. Description of the drawings:

[0025] Figure 1 Schematic diagram of the cathode structure of the present invention;

[0026] Figure 2 This is a schematic diagram of the structure of the segmented cathode copper body of the present invention;

[0027] Figure 3 This is a schematic structural diagram of the intermediate connecting device of the present invention;

[0028] Figure 4 Schematic diagram of the pull rod structure of the present invention;

[0029] Figure 5 It is a schematic diagram of the sleeve tooling structure of the present invention;

[0030] Figure 6 It is a schematic diagram of the overall device of the present invention;

[0031] In the figure: 1. cathode body; 2. limiting threaded hole; 3. "O"-shaped sealing ring; 4. liquid outlet hole; 5. front guide; 6. segmented cathode copper body; 7. multi-tooth working teeth; 8. wedge-shaped positioning keyway; 9. rear guide; 10. prism; 11. internal thread; 12. intermediate connecting device; 13. waterproof pad; 14. countersunk screw hole; 15. sealing ring; 16. outer insulation layer; 17. pull rod; 18. external thread; 19. sleeve tooling; 20. sealing pad; 21. workpiece; 22. support seat. Specific implementation method:

[0032] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0033] The present invention is a multi-tooth segmented electrolytic machining cathode and tooling for rifling large-caliber artillery barrels, comprising a cathode body 1, a segmented cathode copper body 6, a rear guide 9, an intermediate connecting device 12, a pull rod 17, and a sleeve tooling 19. The segmented cathode copper body 6 with multi-toothed working teeth on the cathode body 1 is fixed in series by a wedge key, and the rear guide 9 is assembled on the tail end of the cathode body 1 by a threaded connection. The conical end of the cathode body 1 is sealed with the end face of the waterproof pad 13 of the intermediate connecting device 12. The "O"-shaped sealing ring 3 of the front guide 5 of the cathode body prevents electrolyte leakage during processing. The sealing ring 15 at the right port of the intermediate connecting device 12 seals the conical surface of the cathode body 1. The countersunk screw hole 14 and the limiting threaded hole 2 at the conical end of the cathode body are fastened by screws. The cathode body 1, the pull rod 17 and the intermediate connecting device 12 are rotated and fed together. During processing, the cathode body 1, the pull rod 17, the intermediate connecting device 12 and the sleeve tooling 19 are coaxial. After the processing is completed, the cathode body 1 is completely entered into the sleeve tooling 19.

[0034] The inner wall of the segmented cathode copper body 6 on the cathode body 1 is provided with a wedge-shaped positioning keyway 8, and the segmented cathode copper body 6 is fixed in series using a wedge-shaped key, and the multi-toothed working teeth on the segmented cathode copper body 6 have different characteristic parameters (such as the negative line angle, the positive line angle, the tooth width, the tooth depth, the winding angle, etc.).

[0035] The rear guide of the cathode body 1 is a ring-shaped piece, which is tightened by rotating the prism 10 when threadedly connected to the cathode body 1; the workpiece 21 is in clearance fit with the outer cylinder of the rear guide 9 to support the cathode body 1.

[0036] The outer diameter of the intermediate connecting device 12 is consistent with that of the pull rod 17. The left side of the intermediate connecting device 12 has an internal thread 11 connected to the external thread of the pull rod 17. The right side has a conical fastening structure and a waterproof pad 13 and a sealing ring 15, which cooperate with the limiting threaded hole at the conical end of the cathode body 1. The screw is screwed into the countersunk screw hole 14 and the threaded hole to play a limiting and fixing role. At the same time, the screw can be completely screwed into the countersunk screw hole 14, avoiding the protrusion of the screw interfering with the processing process.

[0037] The outer surface of the pull rod 17 is made of insulating material and the inner material is copper. The pull rod 17 has a double-threaded structure, one end of which is connected to the machine tool spindle through a thread, and the other end is connected to the intermediate connecting device 12 through a thread to ensure smooth connection of the cathode body 1.

[0038] The sleeve tooling 19 is used in conjunction with the cathode body 1, the intermediate connecting device 12, and the pull rod 17 to ensure that the end of the large-caliber artillery barrel is completely precisely formed, thereby avoiding waste of barrel materials.

[0039] Example 1:

[0040] See also Figure 1-Figure 5The present invention provides a multi-tooth segmented electrolytic machining cathode and tooling for large-caliber artillery barrel rifling, comprising a cathode body 1, a segmented copper cathode body 6, a rear guide 9, an intermediate connecting device 12, a pull rod 17, and a sleeve tooling 19. The segmented copper cathode body 6, which has multi-toothed working teeth 7, is fixed in series to the cathode body 1 using a wedge key. This series structure eliminates the need for excessive reliance on the skill level of the assembly worker, and prevents misalignment between the segmented copper cathode bodies, which could affect machining accuracy.

[0041] A limiting threaded hole 2 is provided at the conical end of the cathode body 1. When in use, the conical end of the cathode body 1 is inserted into the conical hole of the intermediate connecting device 12, and after rotating it for a certain angle, the limiting threaded hole 2 on the cathode body 1 is aligned with the countersunk screw hole 14 in the intermediate connecting device 12, and screws are used to connect them to achieve the limiting fixation of the cathode body 1. The electrolyte circulating during the processing is sealed by the "O"-shaped sealing ring 3 of the front guide 5 of the cathode body 1 to ensure the normal progress of the processing. The segmented cathode copper body structure means that even if the cathode is damaged, there is no need to replace the entire cathode. The rear guide 9 of the cathode body 1 is an annular part, which is threadedly connected to the cathode body 1 by rotating the prism 10. The workpiece 21 is gap-fitted with the outer cylindrical part of the rear guide 9 to support the cathode body 1.

[0042] Example 2:

[0043] See also Figure 2 Compared with the existing cathode working teeth with the same parameters, the present invention uses multi-tooth working teeth 7 (with different characteristic parameters such as negative line angle, positive line angle, tooth width, tooth depth, and winding angle) on the segmented cathode copper body 6. Through a single test, the research on the influence of different tooth profile structures on the rifling processing of large-caliber artillery barrels can be obtained, thereby avoiding the disadvantages of many tests for cathode teeth with the same parameters and a long cathode development cycle.

[0044] Example 3:

[0045] See also Figure 1 and Figure 3The conical end of the cathode body 1 is sealed against the waterproof gasket 13 of the intermediate connecting device 12. The O-ring 3 on the front guide 5 of the cathode body 1 prevents electrolyte leakage during processing. The sealing ring 15 on the right end of the intermediate connecting device 12 seals the conical surface of the cathode body. The countersunk screw hole 14 and the limiting threaded hole 2 at the conical end of the cathode body 1 are fastened by screws, forming a conical fastening structure between the cathode body 1 and the intermediate connecting device 12. This structure completely compensates for the defect that the cathode is difficult to remove from the tie rod after long-term rotary feed processing. It also solves the problem that the connecting threads of the cathode and tie rod will be scrapped if the cathode and tie rod are damaged, thereby reducing the cost of electrolytic processing. The intermediate connecting device 12 is connected to the tie rod 17 via threads. Its outer diameter is the same as the outer diameter of the insulating layer 16 outside the tie rod 17. It rotates and feeds synchronously with the tie rod 17 as a whole. During processing, the cathode body 1, tie rod 17, intermediate connecting device 12, and sleeve tooling 19 are coaxial. After processing is completed, the cathode body 1 is completely inserted into the sleeve tooling 19.

[0046] Example 4:

[0047] See also Figures 1-6 The support seat 22 plays the role of supporting the tooling. The rear end hole of the tooling is consistent with the outer diameter of the workpiece 21, and the two are end-face sealed. When in use, the workpiece 21 is embedded in the rear end hole of the sleeve tooling 19 that is consistent with its outer diameter. If the outer diameter of the workpiece 21 is smaller than the rear end hole diameter of the sleeve tooling 19, a self-tightening steel ring can be installed on the surface of the workpiece 21 and used together with the sleeve tooling 19, and through the end face sealing, when the processing reaches the end, the cathode can enter the sleeve tooling 19 with the same size as the inner diameter of the gun barrel, thereby realizing complete precision forming processing of the end of the workpiece 21.

[0048] The present invention can fully process the workpiece in one go by using the sleeve tooling 19 in conjunction with the cathode body 1, the intermediate connecting device 12, the pull rod 17, and the support seat 22. After processing, the entire section of the workpiece is fully precisely formed without having to be cut off, and there is no waste of workpiece material, which reduces processing costs.

[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any equivalent structural changes made using the contents of the description and drawings of the present invention should be included in the patent protection scope of the invention.

Claims

1. A multi-tooth segmented electrolytic machining cathode for large-caliber artillery barrel rifling, characterized by: The invention comprises a cathode body (1), a segmented cathode copper body (6) having working teeth (7) with various tooth shapes is provided on the cathode body (1), a rear guide (9) is provided at the tail end of the cathode body (1), a front guide (5) is provided at the conical end of the cathode body (1), and an intermediate connecting device (12) is provided between the cathode body (1) and the pull rod (17). During processing, the cathode body (1), the pull rod (17) and the intermediate connecting device (12) rotate and feed together as a whole; The inner wall of the segmented cathode copper body (6) on the cathode body (1) is provided with a wedge-shaped positioning keyway (8), the segmented cathode copper body (6) is fixed in series by using a wedge-shaped key, and the working teeth (7) of various tooth shapes on the segmented cathode copper body (6) have different characteristic parameters, including a negative line angle, a positive line angle, a tooth width, a tooth depth or a winding angle.

2. The cathode for electrolytic machining of multi-toothed rifling grooves of large-caliber artillery barrels according to claim 1, characterized in that: The rear guide (9) of the cathode body (1) is an annular part, which is tightened by rotating the prism (10) when being threadedly connected to the cathode body (1); the workpiece (21) is clearance-matched with the outer cylinder of the rear guide (9).

3. The cathode for multi-tooth segmented electrolytic machining of large-caliber gun barrel rifling according to claim 2, characterized in that: The outer diameter of the intermediate connecting device (12) is consistent with that of the pull rod (17), the internal thread (11) on the left side of the intermediate connecting device (12) is connected to the external thread (18) of the pull rod (17), and the right side of the intermediate connecting device (12) has a conical fastening structure, a waterproof pad (13) and a sealing ring (15), which cooperate with the limiting threaded holes (2) evenly distributed on the circumference of the cone end of the cathode body (1).

4. The cathode for multi-tooth segmented electrolytic machining of large-caliber gun barrel rifling according to claim 3, characterized in that: The outer surface of the pull rod (17) is made of insulating material, and the inner material is copper. The pull rod (17) is a double-threaded structure, one end of which is connected to the machine tool spindle through a thread, and the other end of which is connected to the intermediate connecting device (12) through a thread.

5. The cathode for multi-tooth segmented electrolytic machining of large-caliber gun barrel rifling according to claim 4, characterized in that: The conical end of the cathode body (1) is sealed with the end face of the waterproof gasket (13) of the intermediate connecting device (12).

6. The cathode for multi-tooth segmented electrochemical machining of large-caliber gun barrel rifling according to claim 5, characterized in that: An O-shaped sealing ring (3) and a liquid outlet hole (4) are provided on the front guide (5) of the cathode body (1).

7. The cathode for multi-tooth segmented electrolytic machining of rifling of large-caliber gun barrels according to claim 6, characterized in that: The intermediate connection device (12) is evenly provided with countersunk screw holes (14) having the same number as the limiting threaded holes (2), and the countersunk screw holes (14) are fastened to the limiting threaded holes (2) at the conical end of the cathode body (1) by screws.

8. The multi-tooth segmented electrolytic machining cathode for rifling of a large-caliber gun barrel according to claim 1 is used as a tool for a large-caliber gun barrel. A sleeve tool (19) having the same size as the inner diameter of the gun barrel is provided at the end of the gun barrel workpiece. When the outer diameter of the workpiece (21) is smaller than the rear end aperture of the sleeve tool (19), a self-tightening steel ring is sleeved on the outer surface of the workpiece (21) for use together with the sleeve tool (19). The sleeve tool (19) is connected to the gun barrel. The sleeve tool (19) is made of metal and is used in conjunction with the cathode body (1), the intermediate connecting device (12), and the pull rod (17).

9. The multi-tooth segmented electrolytic machining cathode for large-caliber gun barrel rifling according to claim 8 is used in a tooling for large-caliber gun barrels, characterized in that: During processing, the cathode body (1), the pull rod (17), the intermediate connecting device (12) and the sleeve tooling (19) are coaxial, and after processing is completed, the cathode body (1) is completely inserted into the sleeve tooling (19).

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