Hard alloy reverse scraper

Abstract

The utility model provides a hard alloy reverse scraping knife which comprises a knife rod, one end of the knife rod is fixedly connected to a knife handle, the other end of the knife rod is vertically provided with a reverse scraping knife body, the knife point of the reverse scraping knife body faces the knife handle, the reverse scraping knife body comprises a knife body and a knife blade, and the knife body is of a special-shaped polygon centrosymmetric structure. Blade tables are machined on the opposite side faces of the cutter body and the two tail ends away from each other, and the blades are fixedly installed in the blade tables. The reverse scraper is axially locked and fixed through the square through hole formed in the top of the cutter bar and the inner hexagonal countersunk head screw, so that the reverse scraper is convenient to mount and dismount and simple in structure; only the hard alloy blade is welded on the reverse scraping knife body, and the knife point forms a specific rotation diameter after edge grinding, so that the reverse scraping knife meets the processing of counter bores with specific specifications, has high hardness, high toughness and better wear resistance, prolongs the service life by more than 15 times, and is suitable for large-scale production and processing.

Description

Technical Field

[0001] The utility model relates to a hard alloy reverse scraper. Background Art

[0002] Most mounting holes for housing parts and equipment are internal and external countersunk structures, requiring high dimensional accuracy and tight production cycles. To ensure product quality and production efficiency, reverse scrapers are often used for processing. Reverse scrapers are commonly used tools for CNC machine tools. Traditional countersinking reverse scrapers use high-speed steel formed milling cutters, which have poor wear resistance at high temperatures. Since the magnesium alloy casting cabin has a hardened layer on its surface and coolant cannot be used for lubrication and cooling during processing, the high-speed steel formed reverse scrapers suffer severe wear and unstable product quality. How to effectively solve technical problems such as the poor wear resistance of high-speed steel formed reverse scrapers and the difficulty in ensuring product processing quality is of great significance to the final product and benefits.

[0003] like Figure 3 The figure shows the dimensions of a shell countersink. The countersink is located in the narrow inner cavity of the cabin, with a diameter of Φ85mm. The depth of the countersink is 99+0.12+0.04mm from the cabin exterior, with a roughness requirement of no more than 3.2. The part is made of cast magnesium alloy ZM6, and the dimensional requirements are high. To ensure product processing quality and efficiency, a reverse scraper is often used for processing. Traditional countersinking scrapers use high-speed steel profile milling cutters, which have poor wear resistance at high temperatures. Because the magnesium alloy cast cabin has a hardened layer on its surface, coolant cannot be used for lubrication and cooling during processing, resulting in severe wear of the high-speed steel profile scraper and unstable product quality.

[0004] Existing scrapers use integral carbide formed reverse scrapers instead of high-speed steel formed reverse scrapers for countersinking. This method can effectively solve the problem of poor wear resistance of high-speed steel formed reverse scrapers. However, integral carbide formed reverse scrapers are expensive, more than 10 times the cost of high-speed steel formed reverse scrapers.

[0005] For example, a bolt countersink scraper disclosed in announcement number CN207508432U uses ordinary high-speed steel tools to scrape countersinks, which has poor wear resistance and unstable product processing quality.

[0006] For example, a welded carbide forming milling cutter for machining blade tenons disclosed in announcement number CN103071838 cannot be used to machine countersinks inside cabins and is only suitable for machining external features. Utility Model Content

[0007] In order to solve the above technical problems, the utility model provides a hard alloy reverse scraper.

[0008] The utility model is achieved through the following technical solutions.

[0009] The utility model provides a carbide reverse scraper, comprising a knife rod, one end of the knife rod is fixedly connected to the knife handle, and the other end is vertically installed with a reverse scraper, the tip of the reverse scraper faces the knife handle, and the reverse scraper comprises a knife body and a blade, the knife body is a center-symmetrical structure of an irregular polygon, and blade platforms are processed on the opposite sides of the knife body and the two ends away from each other, and the blade is fixedly installed in the blade platform.

[0010] The front angle α of the blade is 25°, the back angle β1 is 16°, and the secondary back angle β2 is 10°. The adjacent surfaces of the cutter body and the blade are respectively on the same plane.

[0011] The shape of the bottom of the blade is a curve that bends upward from the end of the blade to the middle of the blade, and the shape of the blade platform is the same as that of the blade.

[0012] The middle section of the knife body is square, and the middle of the side surface of the knife body perpendicular to the blade is also processed with a square depression.

[0013] The square depression is placed in the square perforation, and the square perforation is processed on the knife rod. A locking screw is installed at the end of the knife rod to fix the counter scraper.

[0014] The beneficial effects of the utility model are: the square through-hole provided on the top of the arbor is used to axially lock and fix the reverse scraper with a hexagonal countersunk screw, so that the reverse scraper is easy to install and disassemble and has a simple structure; only the carbide blade is welded to the reverse scraper body, and the tip of the blade is formed into a specific rotation diameter after sharpening to meet the requirements of specific specifications of countersinking processing, with high hardness, high toughness and good wear resistance, and the service life of the tool is increased by more than 15 times, making it suitable for mass production and processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural diagram of the utility model;

[0016] Figure 2 This is a schematic structural diagram of a rice scraper according to the present invention;

[0017] Figure 3 Schematic diagram of the countersink structure to be processed;

[0018] In the figure: 1-anti-scraper, 11-blade body, 12-blade, 13-square depression, 14-bevel, 15-blade base, 2-blade rod, 3-shank, 4-locking screw, α-front angle, β1-back angle, β2-secondary back angle. DETAILED DESCRIPTION

[0019] The technical solution of the present invention is further described below, but the scope of protection claimed is not limited to the described solution.

[0020] A cemented carbide reverse scraper comprises a shank 2, one end of which is fixedly connected to a shank 3, and a reverse scraper 1 is vertically mounted on the other end, with the tip of the reverse scraper 1 facing the shank 3. The reverse scraper 1 comprises a blade body 11 and a blade 12. The blade body 11 is a centrally symmetrical structure of a special-shaped polygon. Blade rests 15 are machined on opposite sides of the blade body 11 and at both ends, which are spaced apart from each other. The blade 12 is fixedly mounted within the blade rests 15. The cemented carbide blade is welded to the reverse scraper body and sharpened to a specific rotation diameter to meet specific countersinking specifications. The cemented carbide grade is YG6, which has high hardness, high toughness, and good wear resistance. This increases the tool life by more than 15 times, making it suitable for mass production.

[0021] Further, such as Figure 2 As shown, the blade 12 has a rake angle α of 25°, a clearance angle β1 of 16°, and a secondary clearance angle β2 of 10°. The adjacent surfaces of the blade body 11 and blade 12 are coplanar. The two sides of the blade body are initially machined flat, followed by a bevel 14 aligned with the blade, and finally a blade support 15. This results in a blade body with a narrower width at both ends than at its center, making it easier to pass through the square hole.

[0022] The welded carbide reverse scraper has strong sharpness and has a good cutting effect for magnesium alloy material processing.

[0023] Furthermore, the bottom of the blade 12 is shaped like a curve that bends upward from the end of the blade 12 to the middle of the blade 12, and the shape of the blade platform 15 is the same as that of the blade 12. The blade 12 and the blade platform 15 fit together, and the curved blade platform can provide just the right support for the blade during processing, preventing the welding rake between the blade and the cutter body from breaking.

[0024] Furthermore, the middle section of the cutter body 11 is square, and a square recess 13 is also processed in the middle of the side of the cutter body 11 perpendicular to the blade 12. The square recess is easier to fix and is installed on the guide rod, which makes it easier to limit the rotation of the cutter body.

[0025] Furthermore, the square recess 13 is placed in the square perforation, which is machined on the blade 2. The end of the blade 2 is equipped with a locking screw 4 to fix the reverse scraper 1. The square perforation fits in with the square body in the middle of the blade body. The locking screw is pressed against one side of the square perforation, so that the three sides of the square perforation fit precisely with the three sides of the square body.

[0026] like Figure 2As shown, the welded carbide reverse scraper includes a cutter body and a carbide blade. The cutter body is a centrally symmetrical structure of an irregular polygon. Two positioning steps for welding the carbide blade are provided on the cutter body. A sunken plane for bolt tightening when connected to the cutter rod is provided on one side of the middle of the cutter body. The carbide reverse scraper matches the diameter of the processed countersink, so the diameter of the welded carbide reverse scraper is Φ85mm. The welded carbide blade is used for processing magnesium alloy casting materials and needs to have strong sharpness. The front angle α is 25°, the back angle β1 is 16°, and the secondary back angle β2 is 10°.

[0027] like Figure 1 As shown, the welded carbide reverse scraper 1 is installed into the square through-hole at the top of the tool rod 2, so that the tip of the reverse scraper faces the machine tool spindle to realize the reverse scraping processing. The welded carbide reverse scraper 1 is fixed in the square through-hole of the tool rod 2 with the locking screw 4. After the tool rod 2 is connected with the tool handle 3, it is installed into the machine tool spindle to realize product production and processing.

Claims

1. A cemented carbide reverse scraper, characterized in that The utility model comprises a knife rod (2), one end of the knife rod (2) is fixedly connected to the knife handle (3), and a reverse scraper (1) is vertically installed at the other end, the tip of the reverse scraper (1) faces the knife handle (3), and the reverse scraper (1) comprises a knife body (11) and a blade (12), the knife body (11) is a center-symmetrical structure of a special-shaped polygon, and blade platforms (15) are processed on the opposite sides of the knife body (11) and the two ends away from each other, and the blade (12) is fixedly installed in the blade platform (15); The middle section of the blade body (11) is square, and a square depression (13) is processed in the middle of the side surface of the blade body (11) perpendicular to the blade (12); The square recess (13) is placed in a square perforation, and the square perforation is processed on the knife rod (2). A locking screw (4) is installed at the end of the knife rod (2) to fix the reverse scraper (1).

2. The carbide reverse scraper according to claim 1, characterized in that: The front angle (α) of the blade (12) is 25°, the back angle (β1) is 16°, and the secondary back angle (β2) is 10°. The adjacent surfaces of the knife body (11) and the blade (12) are respectively on the same plane.

3. The cemented carbide reverse scraper according to claim 2, characterized in that: The bottom of the blade (12) is in the shape of a curve that bends upward from the end of the blade (12) to the middle of the blade (12), and the shape of the blade platform (15) is the same as that of the blade (12).

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