Machine tool and circular tube special-shaped groove forming tool thereof

Abstract

The invention relates to a machine tool and a circular tube special-shaped groove forming tool thereof in the technical field of metal cutting tools. The machine tool comprises a tool apron, a first tool strip and a second tool strip. An annular groove is formed in the middle of the upper end face of the tool apron, fan-shaped grooves are formed in the tool apron in the circumferential direction at intervals to form a first fixing block and a second fixing block, and the annular groove penetrates through the first fixing block and the second fixing block. The first cutter strip is fastened on the front side face of the first fixing block, the inner side cutting edge face of the first cutter strip extends into the annular groove, the second cutter strip is fastened on the front side face of the second fixing block, the outer cutting edge face of the second cutter strip extends into the annular groove, and the upper end face of the first cutter strip and the upper end face of the second cutter strip are both higher than the upper end face of the cutter holder. And a gap is formed between the inner cutting edge surface of the first cutter strip and the outer cutting edge surface of the second cutter strip in the annular groove along the radial direction of the end surface of the cutter holder, and is used for forming an annular wall between the grooves. According to the method, the scraping machining efficiency and the stability of the machining quality are greatly improved, and cost reduction and efficiency improvement are remarkable.

Description

Technical Field

[0001] This invention relates to the field of metal cutting tool technology, specifically to a machine tool and a tool for forming irregular grooves in round tubes. Background Technology

[0002] When welding boiler header pipe joints, the groove surface of the pipe hole is often irregularly shaped to meet the welding quality requirements. This includes irregularly shaped grooves formed by planes, stepped surfaces, bosses, arc surfaces, and bevels (or grooves). The original process involved machining on a radial drilling machine. The operator would grind the cutting edge according to the profile, scrape and machine the plane and stepped surfaces according to the procedure, drill the Φ8 center hole, and then machine the arc and bevel surfaces. This process involved many steps, resulting in inconsistent quality. The Φ30 bottom plane has a large contact area and requires high surface roughness, necessitating manual grinding to meet the processing requirements. This resulted in a large workload, high operator skill requirements, low efficiency, high noise levels, and negatively impacted worker occupational health. The instability of the formed surface quality also affected the welding quality of the pipe joints.

[0003] Currently, a common machining process on CNC drilling machines uses a two-tool combination, reducing multiple processes to two. Process A processes the boss surface and center hole, while process B, using the center hole for positioning, processes the bottom plane, stepped surface, arc surface, and bevel surface. This process requires tool changing, and the machining surfaces of irregular holes need to be smoothly connected, demanding high operator skills and a strong sense of responsibility. Errors in the connection of irregular surfaces will affect the quality of subsequent pipe fitting welding, causing inconvenience to production. For example, CN102601400 A relates to a multi-insert vertical lathe tool, including a tool holder, a tool shank fixedly connected to the tool holder, and inserts welded to or secured to the end of the tool shank by fasteners. The inserts include top face inserts, bottom face inserts, and internal hole inserts, each mounted at a characteristic angle to the end of the tool shank by screws. While this disclosed technology solves the problem of insert replacement by mounting multiple inserts on the same tool holder, it does not allow multiple inserts to operate and machine simultaneously. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the purpose of this invention is to provide a machine tool and a tool for forming irregular grooves in round tubes.

[0005] A circular tube irregular groove forming tool provided by the present invention includes a tool holder, a first tool bar and a second tool bar; The upper end face of the tool holder is provided with an annular groove in the middle, and the tool holder is provided with fan-shaped grooves spaced apart around its circumference to form a first fixing block and a second fixing block. The annular groove passes through the first fixing block and the second fixing block. The first blade is fastened to the front side of the first fixing block, and the inner cutting edge of the first blade extends into the annular groove. The second blade is fastened to the front side of the second fixing block, and the outer cutting edge of the second blade extends into the annular groove. The upper end faces of both the first blade and the second blade are higher than the upper end face of the tool holder. A gap is provided between the inner cutting edge of the first blade and the outer cutting edge of the second blade located in the annular groove along the radial direction of the end face of the tool holder. The gap is used to form an annular wall between the grooves. In a top-view projection, the first and / or second cutting blades are set at an angle α to the center line of the tool holder, with the angle α being 0° to 5°.

[0006] In some embodiments, the first and / or second blades are set at an angle α to the center line of the blade holder, with the angle α being 3° to 5°.

[0007] In some embodiments, the first cutting edge includes a beveled edge and a circular arc edge, the beveled edge and the circular arc edge being arranged sequentially from the outside to the inside, and the circular arc edge being the inner cutting edge of the first cutting edge.

[0008] In some embodiments, the second cutting edge includes a flat cutting edge and a stepped cutting edge, wherein the flat cutting edge and the stepped cutting edge are arranged perpendicularly to each other, and the stepped cutting edge is the outer cutting edge of the second cutting edge.

[0009] In some embodiments, the first blade is detachably connected and fastened to the first fixing block, and / or the second blade is detachably connected and fastened to the second fixing block.

[0010] In some embodiments, a third cutting edge is also included, and a third fixing block is formed on the cutting edge holder. The third cutting edge is fastened to the front side of the third fixing block. The third cutting edge includes a second planar blade that extends into the annular groove. The upper end face of the second planar blade is lower than the upper end face of the first planar blade. The second planar blade is used to scrape the upper end face of the annular wall.

[0011] In some embodiments, the third blade is detachably connected and fastened to the third fixing block.

[0012] In some embodiments, in a top-view projection, the center line of the third cutter bar is set at an angle α to the center line of the cutter holder, with the angle α being 0° to 5°.

[0013] In some embodiments, in a top-view projection, the center line of the third cutter bar is set at an angle α to the center line of the cutter holder, with the angle α being 3° to 5°.

[0014] The present invention also provides a machine tool that uses the aforementioned round tube irregular groove forming tool.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. The circular tube irregular groove forming tool of the present invention cleverly solves the problem of local surface cutting transition during the processing of irregular grooves by setting an annular groove, realizes the one-time processing of irregular grooves, and the continuous connection of the surface, which greatly improves the scraping processing efficiency and processing quality stability, and significantly reduces costs and increases efficiency.

[0016] 2. The circular tube irregular groove forming tool of the present invention, by adding a third cutting edge for scraping, the third cutting edge also uses an annular groove to achieve the cutting transition of the corresponding structure of the irregular groove, thereby further improving the adaptability to the shape of the irregular groove structure and effectively improving its practicality.

[0017] 3. The circular tube irregular groove forming tool of the present invention improves the matching degree between the cutting edge of the cutting edge and the irregular groove by setting the offset angle between the center line of the cutting edge and the center line of the tool holder, reduces the wear of the cutting angle of the cutting edge of the cutting edge, extends the tool service life, improves the cutting conditions, improves the surface quality, and at the same time ensures that the cutting powder and other materials flow out from the gap between the cutting edge and the cutting edge fixing block and the fan-shaped groove without damaging the base material. Attached Figure Description

[0018] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the main structure of the circular tube irregular groove forming tool of the present invention; Figure 2 This is a top view schematic diagram of the circular tube irregular groove forming tool of the present invention; Figure 3 for Figure 2 A schematic diagram of the structure along direction A; Figure 4 for Figure 2 A schematic diagram of the B-direction structure; Figure 5 for Figure 2 A schematic diagram of the C-direction structure; Figure 6 This is a schematic diagram of a structure where the first cutting tool of the present invention is a circular arc bevel cutting tool; Figure 7 This is a schematic diagram of the assembly structure of a tool for forming irregular grooves on a round tube during machining. Figure 8 A cross-sectional view of the machined irregular-shaped groove; Figure 9 This is a top view of the shaped groove that has been machined. Detailed Implementation

[0019] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0020] Example 1 This embodiment provides a tool for forming irregular grooves in a circular tube, such as... Figure 1-9 As shown, it includes a tool holder 1 and a first cutting bar 2 and a second cutting bar 3 mounted on the tool holder 1.

[0021] Reference Figure 1 As shown, the tool holder 1 has a boss-shaped structure, including an upper tool holder head 101 for mounting the tool bar and a lower tool holder shank 102 for fixing it to the lathe. Both the tool holder head 101 and the tool holder shank 102 are cylindrical, with the diameter of the tool holder head 101 being larger than the diameter of the tool holder shank 102. The first tool bar 2 and the second tool bar 3 are mounted on the tool holder head 101. (Refer to...) Figure 2 As shown, an annular groove 10 is provided on the upper end face of the tool holder head 101, and the annular groove 10 is concentrically arranged with the tool holder head 101. The depth and width of the annular groove 10 are set according to the structural parameters of the irregular groove to be formed. Multiple spaced fan-shaped grooves are formed on the tool holder head 101 by removing material, and fixing blocks for fixing the tool bar are formed between the fan-shaped grooves. In this embodiment, three spaced fan-shaped grooves are formed in the circumferential direction of the tool holder head 101, and three fixing blocks for fixing the tool bar are formed between the three fan-shaped grooves, two of which are respectively referred to as the first fixing block 11 and the second fixing block 12. The annular groove 10 passes through the three fixing blocks, including the first fixing block 11 and the second fixing block 12.

[0022] Reference Figure 3-4 As shown, both the first cutting tool 2 and the second cutting tool 3 are plate structures with screw holes. Screw holes are also provided on the first fixing block 11 and the second fixing block 12. The first cutting tool 2 is fastened to the front side of the first fixing block 11, and the second cutting tool 3 is fastened to the front side of the second fixing block 12, using screws. Here, the "front side of the first fixing block 11" and the "front side of the second fixing block 12" refer to the side facing forward during the cutting motion of the tool holder 1. (Refer to...) Figure 6As shown, the first cutting tool 2 is a circular arc bevel cutting tool, comprising a beveled edge 21 and a circular arc edge 22 arranged sequentially from the outside to the inside. "From the outside to the inside" means that after the first cutting tool 2 is installed on the first fixing block 11, the direction is from the outer circumference of the tool holder head 101 towards the center. After the first cutting tool 2 is securely connected to the front side of the first fixing block 11, the profile of the beveled edge 21 is basically located outside the annular groove 10, and the profile of the beveled edge 21 extends beyond the circumference of the tool holder head 101, in order to achieve the purpose of cutting the circular tube to form a bevel. At this time, the outer circumference of the tool holder head 101 can form a cone shape to accommodate the profile of the beveled edge 21. Part of the profile of the circular arc edge 22 is located inside the annular groove 10, and there is a pre-set gap between the profile of the circular arc edge 22 and the inner circumference of the annular groove 10. Here, the inner circumference of the annular groove 10 refers to the circumference close to the center of the tool holder head 101. The second cutting blade 3 is a double-sided scraping blade, comprising a first planar cutting edge 31 and a stepped cutting edge 32 arranged perpendicularly to each other. The second cutting blade 3 is preferably rectangular, in which case the first planar cutting edge 31 and the stepped cutting edge 32 are two adjacent edges with an included angle of 90°. After the second cutting blade 3 is fastened to the front side of the second fixing block 12, its first planar cutting edge 31 extends substantially from the center of the tool holder head 101 into the annular groove 10, and its first planar cutting edge 31 is higher than the end face of the tool holder head 101 by a predetermined distance. In this embodiment, the first planar cutting edge 31 and the apex height of the arc cutting edge 22 are set at the same height, while part of the stepped cutting edge 32 is located within the annular groove 10. After installation, the cutting surfaces of the stepped cutting edge 32 and the arc cutting edge 22 within the annular groove 10 are spaced at a predetermined distance along the radial direction of the annular groove 10. This predetermined distance is the thickness of the annular wall between the grooves in the irregular groove to be formed. Specifically, in this embodiment, the annular wall between the arc bevel groove formed after the first cutting blade 2 and the groove formed after the second cutting blade 3.

[0023] Reference Figure 2 As shown, after the first cutting blade 2 is fastened to the front side of the first fixing plate 11 by screws, the centerline of the first cutting blade 2 is offset from the centerline of the tool holder 1 at an angle α of 0° to 5° in its top-view projection plane. Preferably, the offset angle α is 3° to 5°. Furthermore, the centerline of the second cutting blade 3 is also offset from the centerline of the tool holder 1 at an angle α, which is also within the range of 0° to 5°. Preferably, the offset angle α is within the range of 3° to 5°. When multiple cutting blades are installed on the same tool holder for scraping operations, the cutting amount will increase significantly. By setting the offset angle, the wear on the cutting edge angle of the cutting blade can be reduced, the tool life can be extended, the cutting conditions can be improved, the surface quality can be improved, and the cutting powder can be discharged more smoothly, thus improving cutting efficiency.

[0024] The working principle of the cylindrical tube irregular groove forming tool provided in this embodiment is as follows: (Refer to...) Figure 7As shown, the tool holder 1, which is fastened with the first cutting tool 2 and the second cutting tool 3, is placed on a CNC machine tool. After selecting the corresponding machining position for the irregular groove, the tool holder 1 is driven to rotate. During the rotation, the first flat cutting edge 31 and the stepped cutting edge 32 of the second cutting tool 3 successively contact the profile of the round tube to be machined for cutting. At the same time, the arc cutting edge 32 and the bevel cutting edge 31 of the first cutting tool 2 successively contact the profile of the round tube to be machined for cutting. Since there is a predetermined distance between the stepped cutting edge 32 and the arc cutting edge 32 located in the annular groove 10, the annular wall shared by the groove formed by the second cutting tool 3 and the √-shaped beveled arc groove formed by the first cutting tool 2 can be successfully formed. That is, the setting of the annular groove 10 cleverly solves the problem of cutting transition of local profiles during the machining of irregular grooves, realizes the one-time machining of irregular grooves, improves the scraping efficiency and the stability of machining quality, and significantly reduces costs and increases efficiency.

[0025] Example 2 This embodiment 2 is based on embodiment 1. By adding a third cutting blade for scraping, the third blade also utilizes an annular groove to achieve the cutting transition of the corresponding structure of the irregular groove, thereby further improving the adaptability to the shape of the irregular groove structure and effectively improving practicality. Specifically: In this embodiment, refer to Figure 2 and Figure 5 As shown, the third cutting tool 4 is a rectangular plate structure, mainly used for cutting and smoothing the upper surface of the annular wall. In Embodiment 1, three fan-shaped grooves are formed by removing material. Among the three fixing blocks formed between the three fan-shaped grooves, in addition to the first fixing block 11 and the second fixing block 12, the third is referred to as the third fixing block 13. The third cutting tool 4 is fastened to the front side of the third fixing block 13 by screws. Similarly, the front side refers to the side of the cutting direction when the tool holder 1 performs cutting operations. The third cutting tool 4 includes a second planar cutting edge 41, and part of the second planar cutting edge 41 extends into the annular groove 10. The height of the cutting edge of the second planar cutting edge 41 is lower than the height of the first planar cutting edge 31, and the height difference between the two is determined by the height of the annular wall.

[0026] As the tool holder 1 drives the first tool bar 2, the second tool bar 3, and the third tool bar 4 to rotate synchronously, the first tool bar 2 and the second tool bar 3 form a continuous groove with corresponding structures through the annular groove 10. The third tool bar 4, extending into the annular groove 10, is used to scrape the upper surface of the formed annular wall, ensuring that the annular wall reaches a predetermined height and that the upper surface is flat. In this embodiment, the annular groove is also used to ensure the cutting transition of the local surface of the irregular groove.

[0027] A further preferred embodiment is that, in the projection plane at a top angle, the center line of the third blade 4 is also set at an angle to the center line of the blade holder 1, and the angle α is in the range of 0° to 5°, and it is particularly preferred that the angle α is in the range of 3° to 5°.

[0028] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0029] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A tool for forming irregular grooves in round tubes, characterized in that, It includes a tool holder (1), a first tool bar (2), and a second tool bar (3); The upper end face of the tool holder (1) is provided with an annular groove (10), and the tool holder (1) is provided with fan-shaped grooves spaced apart in the circumference to form a first fixing block (11) and a second fixing block (12). The annular groove (10) passes through the first fixing block (11) and the second fixing block (12). The first blade (2) is fastened to the front side of the first fixing block (11). The inner cutting edge of the first blade (2) extends into the annular groove (10). The second blade (3) is fastened to the front side of the second fixing block (12). The outer cutting edge of the second blade (3) extends into the annular groove (10). The upper end faces of the first blade (2) and the second blade (3) are both higher than the upper end face of the tool holder (1). A gap is provided between the inner cutting edge of the first blade (2) and the outer cutting edge of the second blade (3) located in the annular groove (10) along the radial direction of the end face of the tool holder (1). The gap is used to form an annular wall between the grooves. In the top-view projection, the first blade (2) and / or the second blade (3) are set at an angle to the center line of the blade holder (1), with the angle α being 0° to 5°.

2. The circular tube irregular groove forming tool according to claim 1, characterized in that, The first blade (2) and / or the second blade (3) are set at an angle α to the center line of the blade holder (1), with the angle α being 3° to 5°.

3. The circular tube irregular groove forming tool according to claim 1, characterized in that, The first blade (2) includes a beveled edge (21) and a circular arc edge (22). The beveled edge (21) and the circular arc edge (22) are arranged sequentially from the outside to the inside. The circular arc edge (22) is the inner cutting edge of the first blade (2).

4. The circular tube irregular groove forming tool according to claim 1, characterized in that, The second blade (3) includes a planar blade (31) and a stepped blade (32). The planar blade (31) and the stepped blade (32) are arranged perpendicularly to each other. The stepped blade (32) is the outer cutting edge of the second blade (3).

5. The circular tube irregular groove forming tool according to claim 1, characterized in that, The first blade (2) is detachably connected and fastened to the first fixing block (11), and / or the second blade (3) is detachably connected and fastened to the second fixing block (12).

6. The circular tube irregular groove forming tool according to claim 1, characterized in that, It also includes a third blade (4), and a third fixing block (13) is formed on the blade holder (1). The third blade (3) is fastened to the front side of the third fixing block (13). The third blade (4) includes a second planar blade (41). The second planar blade (41) extends into the annular groove (10). The upper end face of the second planar blade (41) is lower than the upper end face of the first planar blade (31). The second planar blade (41) is used to scrape the upper end face of the annular wall.

7. The circular tube irregular groove forming tool according to claim 6, characterized in that, The third blade (4) is detachably connected and fastened to the third fixing block (13).

8. The circular tube irregular groove forming tool according to claim 6, characterized in that, In the top-view projection, the center line of the third blade (4) is set at an angle to the center line of the blade holder (1), and the angle α is 0° to 5°.

9. The circular tube irregular groove forming tool according to claim 7, characterized in that, In the top-view projection, the center line of the third blade (4) is set at an angle to the center line of the blade holder (1), and the angle α is 3° to 5°.

10. A machine tool, characterized in that, The circular tube irregular groove forming tool as described in any one of claims 1-9 is used.

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