Multi-edge ball-end milling cutter

Abstract

The utility model belongs to the technical field of milling cutters, and particularly relates to a multi-edge ball-end milling cutter. The multi-edge ball-end milling cutter comprises a cutter handle and a hemispherical cutter body which are coaxially connected, a plurality of blade mounting grooves are uniformly formed in the circumferential direction of the cutter body, a blade is arranged in each blade mounting groove, the blades are detachably mounted in the corresponding blade mounting grooves, each blade is of a central symmetry structure, and each blade is provided with two cutting edges which are distributed in a central symmetry mode. The double-sided use of the blade can be realized, so that the service life of the whole ball-end milling cutter is prolonged, and the replacement frequency of the blade is reduced; meanwhile, the blade can be detached and replaced, so that the knife handle and the knife body can be reused, and the use cost is reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of milling cutter tools, in particular to a multi-edge ball-end milling cutter. Background Art

[0002] The ball joint, also known as a "constant velocity universal joint," is a crucial component in a car's transmission system, transferring engine power from the transmission to the drive wheels, propelling the car at high speeds. Due to its harsh operating environment and the complex alternating loads it must withstand, heat treatment processes are often used to ensure its reliability, longevity, and toughness.

[0003] The bell-shaped shell is an important component of the ball cage, and the ball track inside it needs to be processed using a ball-end milling cutter. In the prior art, the ball-end milling cutter structure that can process the bell-shaped shell is a multi-blade ball-end milling cutter disclosed in the Chinese utility model patent with authorization announcement number CN202894453U, which includes a shank and a cutter body connected to the shank as a whole, six cutting edges are provided on the axial end face of the cutter body, coolant channels are provided in the shank and the cutter body, and cooling holes connected to the coolant channels are provided on the cutting edges. The cutter body and the shank of the above-mentioned ball-end milling cutter are connected by welding, and the cutter body has multiple cutting edges, which can improve the processing efficiency, and the multiple cooling holes can achieve coolant coverage of the processing part.

[0004] Another example of a ball-end milling cutter structure capable of machining bell-shaped shells in the prior art is a ball-end milling cutter for machining universal joint ball cage shells, disclosed in authorization publication number CN216541054U. The cutter comprises an integrally connected cutter body and a shank. The cutter body is configured as a hemispherical shape, and the top of the cutter body is configured as a circular plane with a first cooling hole provided on the circular plane. The side surface of the cutter body is provided with four evenly spaced guide surfaces, with a protrusion formed between two adjacent guide surfaces. A second cooling hole is provided on the guide surface, and a blade is also fixedly provided on the guide surface, one side of which is fixedly connected to the inner side of the protrusion. The cutter body and shank of the ball-end milling cutter are also fixed by welding, and the cooling holes are provided to cool the cutting area to reduce tool wear.

[0005] The blades of ball end mills disclosed in the prior art are mostly fixed to the cutter body by welding, with a single processing size and a single blade having only one cutting edge. Once the blade is damaged, the entire ball end mill must be scrapped and cannot be reused. The cost of use is high and the service life is short. Utility Model Content

[0006] The utility model provides a multi-edge ball end milling cutter to solve the technical problems of high use cost and short service life of the existing ball end milling cutters.

[0007] In order to solve the above problems, the utility model provides a multi-edge ball end milling cutter adopting the following technical solutions:

[0008] A multi-blade ball-end milling cutter includes a coaxially connected shank and a hemispherical cutter body. A plurality of blade mounting grooves are evenly arranged in the circumferential direction of the cutter body. A blade is arranged in each blade mounting groove. The blade can be removably installed in the corresponding blade mounting groove. The blade is a centrosymmetrical structure and has two cutting edges distributed centrosymmetrically.

[0009] The beneficial effects of the present invention are as follows: in the present invention, the blade can be disassembled from the cutter body, which is convenient for replacing the blade after it is damaged. Replacing the blade will not cause the entire ball-end milling cutter to be scrapped, so that the cutter handle and cutter body can be reused, which reduces the cost of use, and different types of blades can be replaced to adapt to the processing of structures of different sizes; in addition, the blade has two cutting edges distributed symmetrically around the center. When one of the cutting edges is damaged, the blade can be removed from the cutter body first, and the blade can be rotated 180 degrees and then re-fixed, and the undamaged cutting edge can be used for processing, that is, the blade of the ball-end milling cutter of the present invention can be used on both sides, thereby extending the service life of the blade and reducing the number of times the blade is replaced.

[0010] Furthermore, the cutting edge includes a tangent large cutting edge arc and a small cutting edge arc, and the curvature of the small cutting edge arc is greater than the curvature of the large cutting edge arc.

[0011] Beneficial effect: When processing the same workpiece, the cutting edge used in the utility model can participate in the cutting operation throughout its length, while the existing blade that only uses one cutting edge arc does not participate in the cutting operation along its entire length during actual use. Compared with the existing blade, the cutting edge of the utility model only retains the effective use length, the processed blade length is shorter, and more materials are saved. In addition, the presence of the small cutting edge arc makes the arc-shaped cutting edge have a tip arc, which improves the blade's resistance to breakage.

[0012] Furthermore, after the blade is installed in the blade installation slot, there is a gap between the large arc of the cutting edge and the small arc of the cutting edge located on the inner side and the blade body.

[0013] Beneficial effect: The large arc of the cutting edge and the small arc of the cutting edge do not directly contact the cutter body, which helps to protect the large arc of the cutting edge and the small arc of the cutting edge.

[0014] Furthermore, the blade includes a base and a positioning boss connected to the base, the base and the positioning boss are both centrally symmetrical structures, the cutting edge is arranged on the base, and the blade mounting groove includes a base positioning groove section and a boss positioning groove section that are interconnected, each groove wall of the base positioning groove section is used to position and fit with the corresponding side surface of the base, and each groove wall of the boss positioning groove section is used to position and fit with the corresponding side surface of the positioning boss, and a positioning step is formed between the base positioning groove section and the boss positioning groove section.

[0015] Beneficial effect: convenient for positioning and installing the blade.

[0016] Furthermore, the blade body is provided with a pressure groove in the circumferential direction that corresponds to and is connected to the blade mounting groove. The pressure groove extends to the end face of the blade body. A pressure plate is detachably connected to each pressure groove by a screw. The groove walls of the pressure groove are respectively positioned and fitted with the corresponding side surfaces on the pressure plate. The pressure plate is used to press the blade.

[0017] Beneficial effect: The blade is pressed and fixed by the pressing plate, and there is no need to drill holes on the blade, making processing, installation and disassembly simpler.

[0018] Furthermore, a concave arc groove is provided on the side of the pressure plate facing away from the blade body.

[0019] Beneficial effect: while ensuring the strength of the pressure plate, the chip removal space is increased.

[0020] Furthermore, the pressure plate is provided with a screw through-hole for the screw to pass through, and the screw through-hole passes through the arc groove; the knife body is provided with screw mounting holes corresponding one to one to the screw through-holes, the axis of the screw mounting hole is perpendicular to the axis of the knife handle, and the positions of two adjacent screw mounting holes in the circumferential direction of the knife body are staggered in the axial direction of the knife handle.

[0021] Beneficial effect: It can increase the effective length of the screw entering the cutter body, improve the tightening force, and ensure that the blade is firmly fixed.

[0022] Furthermore, cooling channels arranged obliquely relative to the axis of the tool handle are provided at positions corresponding to the pressure grooves in the tool body, and each cooling channel forms a tool body liquid outlet on the corresponding groove wall of the pressure groove. A guide groove corresponding to the liquid outlet is provided on the pressure plate, and the groove orientation angle of the guide groove is consistent with the cutting angle of the blade during processing.

[0023] Beneficial effect: It can effectively cool the cutting area and reduce blade wear.

[0024] Furthermore, there are four blades.

[0025] Beneficial effect: When the cutter body size allows, it can ensure cutting efficiency and facilitate processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and other objects, features and advantages of the exemplary embodiments of the present invention will become readily understood by reading the detailed description below with reference to the accompanying drawings. In the accompanying drawings, several embodiments of the present invention are shown in an exemplary and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0027] Figure 1This is a schematic diagram of the three-dimensional structure of the multi-edge ball end milling cutter of the present invention;

[0028] Figure 2 for Figure 1 Bottom view of

[0029] Figure 3 Schematic diagram of the three-dimensional structure of the blade body from the first perspective;

[0030] Figure 4 is a schematic diagram of the three-dimensional structure of the blade body from a second perspective;

[0031] Figure 5 A schematic diagram of a blade from a first-person perspective;

[0032] Figure 6 A schematic diagram of the blade from a second perspective;

[0033] Figure 7 Schematic diagram of the three-dimensional structure of the pressure plate.

[0034] Description of reference numerals:

[0035] 1. Tool handle; 2. Tool body; 21. Blade mounting groove; 211. Base positioning groove section; 212. Boss positioning groove section; 22. Pressing groove; 23. Tool body liquid outlet; 24. Cooling channel; 25. Tool body liquid inlet cavity; 26. Screw mounting hole; 3. Blade; 31. Base; 311. Large arc of cutting edge; 312. Small arc of cutting edge; 32. Positioning boss; 4. Pressing plate; 41. Guide groove; 42. Screw hole; 43. Arc groove; 5. Screw. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Those skilled in the art should know that the embodiments described below are part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0037] The principle and spirit of the present invention are explained in detail below with reference to several representative embodiments of the present invention.

[0038] The embodiment of the multi-edge ball end milling cutter provided by the utility model:

[0039] like Figure 1 and Figure 2 As shown, the multi-edge ball end milling cutter comprises a coaxially connected tool holder 1 , a hemispherical tool body 2 , a blade 3 mounted on the tool body 2 , and a pressure plate 4 mounted on the tool body 2 .

[0040] Specifically, the tool handle 1 is used to be connected to a machining device, and the position of the multi-edge ball end milling cutter can be adjusted under the action of the machining device.

[0041] The blade body 2 and the handle 1 are integrally formed, and the end of the blade body 2 facing away from the handle 1 is a flat surface. Figure 1 and Figure 3 As shown, four blade mounting grooves 21 and four pressing grooves 22 are evenly arranged in the circumferential direction of the cutter body 2. A blade 3 is installed in each blade mounting groove 21, and a pressing plate 4 for pressing the blade 3 is installed in each pressing groove 22.

[0042] In this embodiment, the blade 3 is a centrally symmetrical structure. Figure 5 and Figure 6 As shown, the blade 3 comprises an integrally formed base 31 and a positioning boss 32 located on the base 31. The base 31 and the positioning boss 32 are both centrosymmetrical structures, and the horizontal cross-sectional area of ​​the base 31 is larger than that of the positioning boss 32. The cutting edge of the blade 3 is disposed on the base 31, and the base 31 is provided with two cutting edges arranged in a centrosymmetrical manner. Each cutting edge includes a large cutting edge arc 311 and a small cutting edge arc 312 arranged tangentially. The curvature of the small cutting edge arc 312 is greater than that of the large cutting edge arc 311. The large cutting edge arc 311 is used for fine milling, and the small cutting edge arc 312 is used for rough milling. When the cutting edge adopts two arc sections, when processing the same workpiece, the arc cutting edge used in the utility model can fully participate in the cutting operation. Compared with the existing blade that only adopts one cutting edge arc, the arc cutting edge of the utility model only retains the effective use length, the processed blade length is shorter, and more material is saved. In addition, the presence of the small cutting edge arc 312 makes the arc cutting edge have a tip arc, which improves the anti-breakage ability of the blade 3.

[0043] The base 31 also has two positioning planes, a connection surface for connecting the positioning boss 32, and a pressure plane for receiving the pressure of the pressure plate 4. The shape of the positioning boss 32 is not limited, as long as it can meet the positioning and installation requirements of the blade 3.

[0044] like Figure 3As shown, the blade mounting groove 21 includes a base positioning groove section 211 and a boss positioning groove section 212 that are interconnected. Both the base positioning groove section 211 and the boss positioning groove section 212 extend radially along the blade body 2 to the outer peripheral surface of the blade body 2. The groove walls of the base positioning groove section 211 are respectively used to position and mate with the corresponding positioning planes and connecting surfaces of the base 31, while the groove walls of the boss positioning groove section 212 are respectively used to position and mate with the corresponding side surfaces of the positioning boss 32. A positioning step is formed between the base positioning groove section 211 and the boss positioning groove section 212. During installation, the base 31 and the positioning boss 32 are respectively clamped in the base positioning groove section 211 and the boss positioning groove section 212. At this time, a certain gap is left between the large cutting edge arc 311 and the small cutting edge arc 312 located on the inner side of the blade 3 and the blade body 2, which helps protect the cutting edge. The positioning of the blade 3 depends solely on the positioning boss 32 on the blade body 3 . In other embodiments, other parts of the blade 3 except the positioning boss 32 may not contact the blade mounting groove 21 .

[0045] The pressure grooves 22 are mounted one-to-one alongside and communicate with the blade mounting slots 21. They extend radially outward from the blade body 2 to the outer circumference and axially from the handle 1 to the end face of the blade body 2. The pressure plates 4 are screwed into their corresponding pressure grooves 22. The walls of each pressure groove 22 align with the corresponding side faces of the pressure plate 4, securing the blades 3.

[0046] like Figure 2 and Figure 7 As shown, the side of the pressure plate 4 facing away from the cutter body 2 is provided with an inwardly concave arc groove 43, which increases the chip removal space while ensuring strength; the pressure plate 4 is provided with a screw through hole 42 for the screw 5 to pass through, and the screw through hole 42 passes through the arc groove 43. Figure 3 As shown, the blade 2 is provided with screw mounting holes 26 corresponding to the screw through holes 42 one by one. The axis of the screw mounting hole 26 is perpendicular to the axis of the handle 1. The positions of two adjacent screw mounting holes 26 in the circumferential direction of the blade 2 are staggered in the axial direction of the handle 1 to increase the effective length of the screw 5 entering the blade, improve the tightening force, and ensure that the blade 3 is firmly fixed.

[0047] like Figure 4As shown, cooling channels 24 are provided at positions corresponding to the respective grooves 22 in the cutter body 2, which are arranged obliquely relative to the axis of the shank 1. A conical cutter body liquid inlet cavity 25 is provided at the end of the cutter body 2 close to the shank 1, and each cooling channel 24 is connected to the cutter body liquid inlet cavity 25. The shape of the cutter body liquid inlet cavity 25 is not restricted, and other shapes besides the conical shape may also be adopted. Each cooling channel 24 forms a cutter body liquid outlet 23 on the corresponding groove wall of the groove 22. A guide groove 41 is provided on the pressure plate 4, which corresponds to and is connected to the cutter body liquid outlet 23. The notch of the guide groove 41 faces the large arc 311 of the cutting edge, which is consistent with the cutting angle of the blade 3 during processing, so as to guide the coolant to the cutting area of ​​the cutting edge and reduce the wear rate of the blade 3. In actual use, the shape of the pressure plate 4 is also not restricted, but it needs to be able to press and fix the blade 3.

[0048] When assembling the multi-edge ball end milling cutter of the present invention, the base 31 and the positioning boss 32 on the blade 3 are respectively clamped in the base positioning groove section 211 and the boss positioning groove section 212 for positioning, and then the pressure plate 4 is placed in the pressure groove 22 for positioning. At this time, the pressure plate 4 is squeezed and contacted with the pressure surface on the blade 3, and then the screws 5 are installed to fasten the pressure plate 4 to the cutter body 2. The pressure plate 4 squeezes the blade 3 and presses the blade 3 to be fixed on the positioning step.

[0049] When the blade 3 is damaged due to long-term use, the corresponding screw 5 is removed, the pressure plate 4 is removed, and the blade 3 pressed and fixed by the pressure plate 4 can be removed. At this time, the blade 3 is rotated 180 degrees and the blade 3 and the pressure plate 4 are re-fixed. The blade 3 can continue to be used, and the blade 3 now uses the undamaged cutting edge. When both cutting edges on the blade 3 are damaged and cannot be used, the blade 3 can be removed and replaced with a new blade 3.

[0050] The blade 3 of the present invention adopts a double-sided cutting edge and can be used on both sides, which prolongs the service life of the blade 3 and reduces the number of replacement times of the blade 3. At the same time, the blade 3 can be disassembled and replaced, and the handle 1 and the blade body can be reused, which reduces the cost of use.

[0051] It should be noted that in actual applications, the number of blades used is not limited to the four in this application. Depending on the requirements of the workpiece to be processed and the actual size of the cutter body, an appropriate number of blade mounting slots 21 and pressure slots 22 can be machined on the cutter body. For example, if the cutter body is large, more than five blades can be used, and if the cutter body is small, three or two blades can be used.

[0052] In other embodiments, the cutting edge of the blade may also only have a large arc on one end without processing the small arc on the edge.

[0053] In other embodiments, when the thickness of the cutter body is large enough, the screw mounting holes on the cutter body may also be provided at the same position in the circumferential direction of the cutter body, rather than being staggered in the axial direction of the cutter body.

[0054] In the description of this specification, “a plurality of” means at least two, for example, two, three or more, etc., unless otherwise clearly and specifically defined.

[0055] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A multi-edge ball end milling cutter, comprising a coaxially connected shank and a hemispherical cutter body, wherein a plurality of blade mounting grooves are evenly arranged in the circumferential direction of the cutter body, each blade mounting groove is provided with a blade, characterized in that: The blade can be detachably installed in the corresponding blade installation groove. The blade is a centrally symmetrical structure and has two cutting edges that are centrally symmetrically distributed.

2. The multi-edge ball end milling cutter according to claim 1, characterized in that: The cutting edge comprises a tangent large cutting edge arc and a small cutting edge arc, and the curvature of the small cutting edge arc is greater than the curvature of the large cutting edge arc.

3. The multi-edge ball end milling cutter according to claim 2, characterized in that: After the blade is installed in the blade installation groove, there is a gap between the large arc of the cutting edge and the small arc of the cutting edge located on the inner side and the blade body.

4. The multi-edge ball end milling cutter according to claim 2 or 3, characterized in that: The blade includes a base and a positioning boss connected to the base. The base and the positioning boss are both centrally symmetrical structures. The cutting edge is arranged on the base. The blade mounting groove includes a base positioning groove section and a boss positioning groove section that are interconnected. The groove walls of the base positioning groove section are used to position and fit with the corresponding side surfaces of the base, and the groove walls of the boss positioning groove section are used to position and fit with the corresponding side surfaces of the positioning boss. A positioning step is formed between the base positioning groove section and the boss positioning groove section.

5. The multi-edge ball end milling cutter according to any one of claims 1 to 3, characterized in that: The blade body is also provided with a pressure groove in the circumferential direction, which corresponds to and is connected to the blade mounting groove. The pressure groove extends to the end face of the blade body. A pressure plate is detachably connected to each pressure groove by a screw. The groove walls of the pressure groove are respectively positioned and fitted with the corresponding side surfaces on the pressure plate. The pressure plate is used to press the blade.

6. The multi-edge ball end milling cutter according to claim 5, characterized in that: An inwardly concave arc groove is provided on the side of the pressing plate facing away from the cutter body.

7. The multi-edge ball end milling cutter according to claim 6, characterized in that: The pressure plate is provided with a screw through-hole for the screw to pass through, and the screw through-hole passes through the arc groove; the tool body is provided with screw mounting holes corresponding to the screw through-holes one by one, the axis of the screw mounting hole is perpendicular to the axis of the tool handle, and the positions of two adjacent screw mounting holes in the circumferential direction of the tool body are staggered in the axial direction of the tool handle.

8. The multi-edge ball end milling cutter according to claim 5, characterized in that: The positions of the tool body corresponding to the pressure grooves are provided with cooling channels arranged obliquely relative to the axis of the tool handle. Each cooling channel forms a tool body outlet on the corresponding groove wall of the pressure groove. The pressure plate is provided with a guide groove corresponding to and connected to the tool body outlet. The orientation angle of the guide groove is consistent with the cutting angle of the blade during processing.

9. The multi-edge ball end milling cutter according to any one of claims 1 to 3, characterized in that: There are four blades.

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