A milling tool capable of reducing milling impact

Abstract

The present invention discloses a milling tool for reducing milling impact, which comprises: a cutter disc connected to a milling spindle so as to rotate synchronously with the milling spindle; a tool holder, a rear end of which is hinged to the cutter disc through a hinge shaft, and a blade for milling is arranged at a front end of the cutter holder; a connecting rod, a front end of which is hinged to the middle part of the cutter holder; an L-shaped rod, one arm of which is hinged to the rear end of the connecting rod; a damping element connected to the other arm of the L-shaped rod; a spring assembly, which comprises a spring seat arranged on the cutter disc, and a spring arranged between the spring seat and the cutter holder; wherein, when the blade cuts into a workpiece to be milled, the cutting load drives the cutter holder to rotate relative to the cutter disc around the hinge shaft at its rear end, and the spring is compressed; when the blade is about to cut out the workpiece to be milled, the cutter holder rotates relative to the cutter disc around the hinge shaft at its rear end under the action of the spring force, so that the damping element plays a damping role through the action of the connecting rod and the L-shaped rod.

Description

Technical Field

[0001] The present invention relates to a mechanical processing device, in particular to a milling device. Background Art

[0002] Milling is a common machining method that uses milling tools.

[0003] Milling is an interrupted cutting operation. As the tool enters the workpiece, the blade is subjected to the impact load of the workpiece, resulting in compressive stress on the blade surface. Similarly, as the tool exits the workpiece, the compressive stress on the blade gradually decreases, and there is also a relief impact, resulting in tensile stress on the blade surface. Experiments observing tool failure during continuous and intermittent cutting have shown that, while other cutting parameters remain unchanged, tool life for intermittent cutting is significantly lower than that for continuous cutting.

[0004] Therefore, it is believed that the main cause of tool failure during milling is the impact on the insert rather than the wear caused by friction between the tool and the workpiece. Therefore, if the impact on the tool during milling can be reduced, the durability of the insert can be improved.

[0005] In addition, because the blade is generally made of high-hardness cemented carbide, its high hardness can withstand a certain amount of compressive stress, but cannot withstand tensile stress. Therefore, the unloading impact when the tool cuts out of the workpiece and the tensile stress on the blade surface are more damaging to the tool than the extrusion impact load and tensile stress on the blade surface when the tool cuts into the workpiece.

[0006] Based on this, it is desired to provide a milling tool that can reduce cutting impact, so that the impact on the tool can be reduced both when the blade just cuts into the workpiece and when the tool cuts out of the workpiece. Summary of the Invention

[0007] The purpose of the present invention is to provide a milling tool that reduces milling impact. When the blade just cuts into the workpiece, it can gradually retreat in the direction opposite to the cutting force to play a buffering role; when the tool cuts out of the workpiece, it can slowly unload the cutting load on the tool.

[0008] In order to achieve the above object, the present invention proposes a milling tool for reducing milling impact, which comprises:

[0009] a cutter head connected to the milling spindle to rotate synchronously with the milling spindle;

[0010] A tool holder, the rear end of which is hinged to the cutter disc via a hinge shaft, and the front end of the tool holder is provided with a blade for milling;

[0011] a connecting rod, the first end of which is hinged to the middle portion of the tool holder;

[0012] an L-shaped rod, one arm of which is hinged to the tail end of the connecting rod;

[0013] a damping element connected to the other arm of the L-shaped rod;

[0014] a spring assembly comprising a spring seat provided on the cutter disc, and a spring provided between the spring seat and the cutter holder;

[0015] Among them, when the blade cuts into the workpiece to be milled, the cutting load drives the tool holder to rotate around the hinge axis at its tail end relative to the cutter disc, and the spring is compressed; when the blade is about to cut out the workpiece to be milled, the tool holder rotates around the hinge axis at its tail end relative to the cutter disc under the action of the spring force, so that the damping element plays a damping role through the action of the connecting rod and the L-shaped rod.

[0016] Furthermore, in the milling tool of the present invention, the tool holder is further provided with a rod insertion hole; the milling tool further comprises:

[0017] an insert rod vertically arranged on the cutter disc;

[0018] An insertion rod spring is sleeved outside the insertion rod and applies force to the insertion rod in a vertical direction;

[0019] When the tool holder rotates about the hinge shaft at its tail end relative to the cutter disc through a set angle, the tail end of the insertion rod falls into the insertion rod hole to prevent the tool holder from continuing to rotate relative to the cutter disc.

[0020] Furthermore, the milling tool described in the present invention also includes a fixed wedge block, which extends in an arc shape in the circumferential direction of the cutter disc, and the upper surface of the wedge block is an inclined surface, so that when the cutter disc drives the insertion rod to rotate until it contacts the upper surface of the wedge block, the wedge block lifts the insertion rod from the insertion rod hole in the vertical direction.

[0021] Furthermore, in the milling tool of the present invention, the wedge block is fixedly arranged on a fixed sleeve, and the fixed sleeve is used to be connected to the spindle box of the milling spindle.

[0022] Furthermore, in the milling tool described in the present invention, a counterweight block is also provided on the cutter disc.

[0023] Furthermore, in the milling tool described in the present invention, a fixed stopper is further provided on the cutter disc, which is arranged on the other side of the tool holder relative to the spring assembly.

[0024] In this embodiment, the fixed stop is used to limit the rotation of the tool holder relative to the tool disc.

[0025] Furthermore, in the milling tool described in the present invention, the spring assembly further includes an arc-shaped spring guide rod, and the spring is sleeved on the spring guide rod.

[0026] Furthermore, in the milling tool described in the present invention, the damping element includes a damping cylinder.

[0027] Furthermore, the milling tool of the present invention further comprises:

[0028] an arcuate guide rail provided on the cutter disc, wherein the spring seat is slidably connected to the arcuate guide rail so as to be able to slide along the arcuate guide rail;

[0029] a spring adjusting block, which is hinged to the spring seat;

[0030] a spring adjusting bolt seat, which is provided on the cutter disc;

[0031] A spring adjusting bolt passes through a spring adjusting bolt seat threadedly connected thereto and is connected to the spring adjusting block;

[0032] The spring adjusting bolt locking sleeve is threadedly connected to the spring adjusting bolt and abuts against the spring adjusting bolt seat.

[0033] In this embodiment, the above-mentioned components are used to adjust the spring force. It should be noted that although the spring seat can slide along the curved guide rail, this sliding movement is only used to adjust the position of the spring seat during the spring force adjustment process. Once the spring force adjustment is completed, the position of the spring seat is fixed.

[0034] Furthermore, the milling tool of the present invention further comprises:

[0035] a linear guide rail, which is provided on the cutter head;

[0036] a damping element adjusting member capable of sliding along the linear guide rail, the damping element adjusting member being hinged to the damping element via a pin;

[0037] a damping element adjusting bolt seat, which is provided on the cutter head;

[0038] a damping element adjusting bolt passing through a damping element adjusting bolt seat threadedly connected thereto and connected to the damping element adjusting member;

[0039] The damping element adjusting bolt locking sleeve is threadedly connected to the damping element adjusting bolt and abuts against the damping element adjusting bolt seat.

[0040] In this embodiment, the damping element adjustment bolt and the damping element adjustment member adjust the position of the damping element to adjust the L-shaped lever's moment arm, thereby adjusting the damping force. Similarly, while the damping element adjustment member can slide along the linear guide rail, this sliding movement only serves to adjust the position of the damping element adjustment member during the damping force adjustment process. Once the damping force is adjusted, the position of the damping element adjustment member remains fixed.

[0041] During the milling process, when the blade of the milling tool described herein enters the workpiece, the tool holder rotates about the hinge axis at its rear end, overcoming the spring force in the direction of the cutting force. This process ensures that the cutting force is buffered when the blade first enters the workpiece. At this time, although the tool holder still acts on the damping element via the connecting rod and L-shaped rod, the damping element does not exert its damping effect.

[0042] In some preferred embodiments, when the tool holder rotates relative to the cutterhead about its rear hinge axis until the rear end of the plunger fits into the plunger hole, the tool holder ceases rotation relative to the cutterhead and begins to rotate synchronously with the cutterhead. This ensures high rigidity when the blade fully engages the workpiece, resulting in a more stable cutting process. As the blade continues to rotate with the cutterhead, the plunger is lifted.

[0043] When the blade is about to cut out the workpiece, the cutting load decreases sharply. At this time, the tool holder rotates around the hinge axis at its rear end under the action of the spring force in the direction opposite to the cutting force. This rotation acts on the damping element through the connecting rod and L-shaped rod, causing the damping element to play a damping role, thereby slowly returning the tool holder to its original position.

[0044] It can be seen that the milling tool described in the present invention can effectively reduce the milling impact during the milling process. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 A schematic diagram of the three-dimensional structure of the milling tool described in the present invention in one embodiment is shown.

[0046] Figure 2 A schematic diagram of the three-dimensional structure of the milling tool according to one embodiment of the present invention is shown from a rear perspective.

[0047] Figure 3 A schematic diagram of the three-dimensional structure of the back side of the milling tool according to one embodiment of the present invention is shown from another perspective.

[0048] Figure 4 A schematic diagram of the three-dimensional structure of the milling tool according to one embodiment of the present invention is shown from a frontal perspective.

[0049] Figure 5A schematic structural diagram of a connecting rod of a milling tool according to one embodiment of the present invention is shown.

[0050] Figure 6 The structure of a spring adjustment assembly of a milling tool according to one embodiment of the present invention is shown.

[0051] Figure 7 A bottom view of a milling tool according to the invention is shown in one embodiment.

[0052] Figure 8 for Figure 7 Cross-sectional view at EE.

[0053] Figure 9 for Figure 8 Cross-sectional view at NN in the middle.

[0054] Figure 10 for Figure 7 Cross-section at QQ.

[0055] Figure 11 for Figure 10 A partial enlarged view of the V in the middle.

[0056] Figure 12 The structure of the damping oil cylinder piston rod of the milling tool described in the present invention in one embodiment is shown. DETAILED DESCRIPTION

[0057] The milling tool of the present invention will be further explained and illustrated below in conjunction with the accompanying drawings and specific embodiments. However, such explanation and illustration do not constitute an undue limitation to the technical solution of the present invention.

[0058] Figure 1 A schematic diagram of the three-dimensional structure of the milling tool described in the present invention in one embodiment is shown.

[0059] like Figure 1 As shown, in one embodiment, the milling cutter is used to mill a workpiece 33. In the figure, M represents the position where the blade 8 cuts in during the milling process, and N represents the position where the blade 8 cuts out during the milling process. In the prior art, the blade is subjected to a large impact at these two positions, but the present invention can effectively reduce this impact.

[0060] Figure 2 A schematic diagram of the three-dimensional structure of the milling tool according to one embodiment of the present invention is shown from a back side perspective.

[0061] Figure 3 A schematic diagram of the three-dimensional structure of the back side of the milling tool according to one embodiment of the present invention is shown from another perspective.

[0062] Figure 4 A schematic diagram of the three-dimensional structure of the milling tool according to one embodiment of the present invention is shown from a frontal perspective.

[0063] like Figure 2 、 Figure 3 and Figure 4 As shown, in one embodiment of the present invention, the milling tool comprises:

[0064] The cutterhead 2 is connected to the milling spindle 32 via a cylindrical shank at its rear end, rotating synchronously with the milling spindle during the milling process. It should be noted that to accommodate different milling spindles, the interface can adopt different structures. The cylindrical shank used here is only one specific implementation; other structures compatible with milling spindles are also feasible.

[0065] The fixed sleeve 31 is connected to the spindle box (not shown in the figure) of the milling spindle through bolts. The fixed sleeve 31 does not rotate during the milling process.

[0066] The rear end of the tool holder 5 is hinged to the cutterhead 2 via a hinge bolt 4, which serves as the hinge axis. One end of the hinge bolt 4 is threadedly secured to the cutterhead 2, while a nut 3 is threadedly engaged with the other end of the hinge bolt 4. The end face of the nut 3 contacts the stepped surface of the hinge bolt 4. The hole at the rear end of the tool holder 5 aligns with the axial clearance of the hinge bolt 4, enabling rotation about the hinge bolt 4. A blade 8 is mounted in a pocket at the front end of the tool holder 5.

[0067] Figure 5 A schematic structural diagram of a connecting rod of a milling tool according to one embodiment of the present invention is shown.

[0068] like Figure 5 The connecting rod 6 shown is inserted into the holes of the tool holder 5 and the L-shaped rod 26 respectively through the two bolt shafts 61 provided thereon, and is matched with the clearance between each hole and the shaft. The nut is fixed on the two bolt shaft ends of the connecting rod 6, and the end face of the nut is in contact with the step surface of the shaft, and does not contact the surface of the tool holder 5 and the L-shaped rod 26, so as to realize the hinged connection between the connecting rod 6 and the tool holder 5, and the hinged connection between the connecting rod 6 and the L-shaped rod 26.

[0069] Fixed block 7 is fixed to cutterhead 2. One end of spring 9 is fixed to fixed block 7 and passes through holes in cutterhead 5 and spring seat 12. Guided by spring guide rod 10, one end of spring 9 contacts the end surface of spring seat 12. Spring seat retaining screw 13 secures spring seat 12 to cutterhead 2. Damping element 20 is hingedly connected to the arm of L-shaped rod 26.

[0070] from Figure 2 It can also be seen in the figure that in some embodiments, a counterweight 1 is further provided on the cutter disc 2, which is used to balance the weight of other components on the cutter disc when the cutter disc rotates.

[0071] Continue reading Figure 3 In some embodiments, the cutterhead 2 is further provided with an arcuate guide rail 11. The spring seat 12 is slidably connected to the arcuate guide rail 11 via a guide rail pair, enabling it to slide along the arcuate guide rail. It should be noted that while the spring seat 12 can slide along the arcuate guide rail 11, this sliding movement is only used to adjust the position of the spring seat 12 during the spring force adjustment process. Once the spring force is adjusted, the spring seat 12 is secured to the cutterhead 2 using the spring seat securing screw 13, maintaining its position.

[0072] like Figure 6 As shown, the spring adjusting block 15 is hinged to the spring seat 12 by the axial clearance fit between the shaft provided on the spring adjusting block 15 and the hole 121 on the spring seat 12 .

[0073] Continue reading Figure 3 and Figure 6 The spring adjustment bolt seat 16 is fixed to the cutter head 2. The spring adjustment bolt 18 passes through the spring adjustment bolt seat 16, which is threadedly connected to the spring adjustment block 15. The hole of the spring adjustment block 15 is clearance-matched with the polished rod at the end of the spring adjustment bolt 18. The spring adjustment block connecting pin 14 is inserted into the hole at the end of the spring adjustment bolt 18, forming an interference fit, thereby limiting the position of the spring adjustment block 15. In addition, the spring adjustment bolt locking sleeve 17 is threadedly engaged with the outside of the spring adjustment bolt 18. The end face of the spring adjustment bolt locking sleeve 17 is in contact with the end face of the spring adjustment bolt seat 16, playing a tightening role.

[0074] In this way, the spring adjusting bolt 18 can adjust the elastic force of the spring 9 by adjusting the bolt length.

[0075] Figure 7 A bottom view of a milling tool according to the invention is shown in one embodiment. Figure 8 for Figure 7 Cross-sectional view at EE. Figure 9 for Figure 8 Cross-sectional view at NN in the middle.

[0076] like Figure 3 、 Figure 7 、 Figure 8 and Figure 9As shown, in some embodiments, the damping element 20 comprises a damping cylinder. The hole at the end of the damping cylinder piston rod 19 is aligned with the axial clearance of the end of the L-shaped rod 26. The hole at the rear end of the damping cylinder is aligned with the axial clearance of the damping element adjusting member 22. A nut is threadedly connected to the axial end of the damping element adjusting member 22, with the end face of the nut contacting the axial end face of the damping element adjusting member 22 while the end face of the nut does not contact the end face of the lug at the rear end of the damping cylinder, thereby enabling the damping cylinder to rotate about the axis of the damping element adjusting member 22. The cutterhead 2 is also provided with a linear guide 34; the damping element adjusting member 22 is capable of sliding along the linear guide. The damping element adjustment bolt seat 23 is fixed to the cutterhead 2. The damping element adjustment bolt 25 passes through the damping element adjustment bolt seat, which is threadedly connected to it, and is connected to the damping element adjustment member 22. The damping element adjustment member connecting pin 21 is inserted into the hole at the end of the damping element adjustment bolt 25, forming an interference fit, thereby limiting the position of the damping element adjustment member 22. The damping element adjustment bolt locking sleeve 24 is threadedly connected to the damping element adjustment bolt and abuts against the damping element adjustment bolt seat to tighten the damping element adjustment bolt 25.

[0077] In this way, the damping element adjusting bolt 25 can adjust the lever arm of the L-shaped rod 26 through the position of the damping cylinder to achieve adjustment of the damping force.

[0078] Figure 10 for Figure 7 Cross-section at QQ. Figure 11 for Figure 10 A partial enlarged view of the V in the middle.

[0079] See also Figure 4 、 Figure 7 、 Figure 10 and Figure 11 In some embodiments, the milling tool further includes an insert rod 29, which is inserted into the square hole of the cutter head 2, and an insert rod spring 27 is sleeved outside the insert rod 29. A wedge block 30 is fixedly mounted on a fixed sleeve 31, and the wedge block 30 extends in an arc shape in the circumferential direction of the cutter head, and the upper surface of the wedge block 30 is an inclined surface.

[0080] like Figure 10 and Figure 11 As shown, when the insertion rod 29 is not inserted into the insertion rod hole 51 of the tool holder 5, its rear end abuts against the upper surface of the tool holder 5 under the elastic force of the insertion rod spring 27. When the tool holder 5 rotates a certain angle about the hinge axis at its rear end relative to the cutter disc 2, the rear end of the insertion rod 29 will fall into the insertion rod hole 51, preventing the tool holder 5 from further rotating relative to the cutter disc 2. At this time, the lower end of the insertion rod spring 27 can be limited by the insertion rod spring stop pin 28.

[0081] Next, during the milling process, the tool holder 5 will rotate synchronously with the cutter head 2, and at the same time, the insertion rod 29 will also rotate synchronously. When the insertion rod 29 rotates to contact the upper surface of the wedge block 30, the wedge block will lift the insertion rod 29 from the insertion rod hole 51 in the vertical direction, so that the tool holder 5 and the cutter head 2 can rotate relative to each other again.

[0082] During the milling process, when the blade 8 cuts into the workpiece 33, the tool holder 5 rotates around the hinge bolt 4 to overcome the elastic force of the spring 9 in the direction of the cutting force. This process ensures that the cutting force is buffered when the blade just cuts into the workpiece. At the same time, the tool holder 5 compresses the damping cylinder through the connecting rod 6 and the L-shaped rod 26. During the compression process, Figure 12 The rubber cover 35 on the damping cylinder piston is shown to be open, and the damping cylinder can be easily retracted.

[0083] When the plunger 29 is inserted into the plunger hole 51 on the tool holder 5 under the action of the plunger spring 27, it plays a supporting role, and the tool holder 5 no longer rotates relative to the cutter head 2. This process ensures that when the blade fully cuts into the workpiece, it can obtain high rigidity, making the cutting process more stable.

[0084] As blade 8 is about to cut through the workpiece, the cutting load decreases dramatically. As cutterhead 2 rotates, plunger 29 is lifted by wedge block 30. Under the elastic force of spring 9, tool holder 5 rotates in the direction counter to the cutting force, causing the damping cylinder to stretch. During this stretching process, the rubber cover 35 on the damping cylinder piston closes, allowing oil to flow only through the small hole 36 in the damping cylinder piston, providing a damping effect and slowly returning tool holder 5 to its original position. Since the damping cylinder is a well-known component in the prior art, its detailed structure and operating principle will not be discussed here.

[0085] It can be seen that the milling tool of the present invention can effectively reduce the milling impact during the milling process. The milling tool of the present invention has a simple structure, simple manufacturing and maintenance, good reliability, easy operation, and significant effect of improving the durability of the tool.

[0086] The combination of the various technical features in this case is not limited to the combination described in the claims of this case or the combination described in the specific embodiments. All technical features recorded in this case can be freely combined or combined in any way unless there is a contradiction between them.

[0087] It should also be noted that the above-listed embodiments are merely specific embodiments of the present invention. Obviously, the present invention is not limited to the above-listed embodiments. Similar variations or modifications that can be directly derived from or easily conceived by those skilled in the art based on the disclosure of the present invention should fall within the scope of protection of the present invention.

Claims

1. A milling tool for reducing milling impact, characterized in that: include: a cutter head connected to the milling spindle to rotate synchronously with the milling spindle; A tool holder, the rear end of which is hinged to the cutter disc via a hinge shaft, and the front end of the tool holder is provided with a blade for milling; A connecting rod, the first end of which is hinged to the middle part of the tool holder; an L-shaped rod, one arm of which is hinged to the rear end of the connecting rod; a damping element connected to the other arm of the L-shaped rod; A spring assembly, comprising a spring seat disposed on the cutter disc, and a spring disposed between the spring seat and the cutter holder; Wherein, when the blade cuts into the workpiece to be milled, the cutting load drives the tool holder to rotate relative to the cutter disc around the hinge shaft at its rear end, and the spring is compressed; When the blade is about to cut out the milled workpiece, the tool holder rotates relative to the cutter disc around the hinge axis at its rear end under the action of the spring force, so that the damping element plays a damping role through the action of the connecting rod and the L-shaped rod.

2. The milling tool according to claim 1, characterized in that The tool holder is also provided with a rod insertion hole; The milling tool also includes: An insert rod is vertically arranged on the cutter disc; A plunger spring, which is sleeved outside the plunger and applies force to the plunger in a vertical direction; When the tool holder rotates about the hinge shaft at its rear end relative to the tool disc through a set angle, the rear end of the insertion rod falls into the insertion rod hole to prevent the tool holder from continuing to rotate relative to the tool disc.

3. The milling tool according to claim 2, characterized in that It also includes a fixed wedge block, which extends in an arc shape in the circumferential direction of the cutter disc, and the upper surface of the wedge block is an inclined surface, so that when the cutter disc drives the insertion rod to rotate until it contacts the upper surface of the wedge block, the wedge block lifts the insertion rod from the insertion rod hole in the vertical direction.

4. The milling tool according to claim 3, characterized in that The wedge block is fixedly arranged on a fixing sleeve, and the fixing sleeve is used to be connected with a spindle box of a milling spindle.

5. The milling tool according to claim 1, characterized in that A counterweight is also provided on the cutter disc.

6. The milling tool according to claim 1, characterized in that The cutter disc is also provided with a fixed stopper which is arranged on the other side of the cutter holder relative to the spring assembly.

7. The milling tool according to claim 1, characterized in that The spring assembly also includes an arc-shaped spring guide rod, and the spring is sleeved on the spring guide rod.

8. The milling tool according to claim 1, characterized in that The damping element includes a damping cylinder.

9. The milling tool according to any one of claims 1 to 8, characterized in that Also includes: An arc-shaped guide rail is arranged on the cutter disc, and the spring seat is slidably connected to the arc-shaped guide rail so as to be able to slide along the arc-shaped guide rail; A spring adjustment block, which is hinged to the spring seat; A spring adjustment bolt seat, which is arranged on the cutter disc; A spring adjusting bolt passes through a spring adjusting bolt seat threadedly connected thereto and is connected to the spring adjusting block; A spring adjusting bolt locking sleeve is threadedly connected with the spring adjusting bolt and abuts against a spring adjusting bolt seat.

10. The milling tool according to any one of claims 1 to 8, characterized in that Also includes: A linear guide rail, which is arranged on the cutter disc; A damping element adjusting member, which can slide along the linear guide rail, and the damping element adjusting member is hinged to the damping element through a pin shaft; A damping element adjusting bolt seat, which is arranged on the cutter disc; A damping element adjusting bolt, which passes through a damping element adjusting bolt seat threadably connected thereto and is connected to the damping element adjusting member; The damping element adjusting bolt locking sleeve is threadedly connected with the damping element adjusting bolt and abuts against the damping element adjusting bolt seat.

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