A corrugated tube type damping vibration reduction boring bar

Abstract

The utility model discloses a kind of corrugated pipe type damping vibration reduction boring bar, including main rod, adapter connector is installed at the front end of main rod, cutter head body is installed at the front end of adapter connector, forming blade is installed on cutter head body, corrugated pipe damper is set in the front end cavity of main rod.The corrugated pipe type damping vibration reduction boring bar disclosed in the utility model uses corrugated pipe+high-density mass+damper liquid as damping unit, replaces the damping unit of traditional rubber ring+high-density mass+damper liquid, assembly operation is simple, disassembly is convenient, stable and reliable.Full use of the excellent vibration isolation and buffering performance of corrugated pipe, vibration absorption rate reaches 85%-90%, and damping performance is significantly optimized.

Description

Technical Field

[0001] This utility model relates to the field of deep cavity boring machining technology for turning equipment, specifically to a bellows-type damping and vibration-damping boring bar in this field. Background Technology

[0002] In the fields of military, aerospace, and oil exploration equipment manufacturing, the requirements for workpiece machining accuracy are becoming increasingly stringent. High length-to-diameter ratio boring bars are widely used in the machining of slender shaft-like precision parts and cavity-type sealing parts. However, during machining with high length-to-diameter ratio boring bars, the large overhang makes them prone to vibration, resulting in noticeable chatter marks on the workpiece surface. This affects machining accuracy, reduces the lifespan of machine tools and cutting tools, and in severe cases, can cause chipping or breakage of the cutting edge, reducing machining efficiency and even causing sharp noise that can harm the hearing health of operators. Therefore, it is essential to take effective measures to reduce or control tool bar vibration to ensure machining quality and efficiency.

[0003] Currently, large length-to-diameter ratio boring bars mainly employ three vibration reduction technologies: active control, passive control, and semi-active control. Among these, passive control vibration reduction technology has been the most researched. It typically achieves vibration reduction by installing a passive dynamic vibration damper inside the tool holder. This passive dynamic vibration damper consists of a high-density mass block, rubber elements, and damping fluid. The main drawbacks of passive control vibration reduction technology include: the rubber ring buffer at the junction of the high-density mass block and the axial end face of the tool head and tool holder cavity is prone to breakage due to compression deformation during installation and disassembly, requiring high precision in assembly operations; the radial junction of the high-density mass block and tool holder cavity uses a structure with rubber rings at both ends and damping fluid filling the middle. The rubber rings at the seal are in direct contact with the damping fluid, repeatedly subjected to changes in damping fluid volume pressure and temperature, making them prone to aging. The rubber rings are susceptible to fatigue damage, leading to seal failure, resulting in high maintenance costs and limiting the damper's temperature and wear resistance. Utility Model Content

[0004] The technical problem to be solved by this utility model is to address the shortcomings of existing large length-to-diameter ratio boring bars, which have many parts, high assembly requirements, and low reliability. It innovatively proposes a bellows-type damping vibration reduction boring bar, which can overcome the shortcomings of passive dynamic vibration dampers in terms of reliability. It does not use rubber components, makes full use of the excellent vibration isolation and buffering performance of bellows, and has volume compensation function, good energy absorption rate (vibration resistance) and service life.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] An improved bellows-type damping vibration reduction boring bar includes a main rod, an adapter joint installed at the front end of the main rod, a cutter head body installed at the front end of the adapter joint, a shaped cutting blade installed on the cutter head body, and a bellows damper installed in the front cavity of the main rod. The bellows damper includes a high-density mass block and a baffle. The outer diameter of the front end of the high-density mass block is larger than that of the rear end. The front end of the high-density mass block is connected to the baffle at its rear end through an outer bellows. The outer bellows is filled with damping fluid and a small baffle is installed. The rear end of the high-density mass block is connected to the small baffle through an inner bellows. A damping fluid through hole is provided on the small baffle. A guide rod is provided at the front of the high-density mass block. A guide hole and a spring cavity are provided in the middle of the adapter joint. The guide rod passes through the guide hole and is inserted into the spring cavity. An internal hexagonal adjusting screw and a spring are provided in the spring cavity. The internal hexagonal adjusting screw abuts against the guide rod and can move back and forth along the spring cavity. The spring abuts against the internal hexagonal adjusting screw.

[0007] Furthermore, an internal thread is provided at the front of the cavity of the main rod, and a countersunk through hole is provided on the internal thread. An external thread is provided at the rear of the adapter, and an internal thread hole is provided on the external thread. The internal thread of the cavity of the main rod and the external thread at the rear of the adapter can be matched to screw the main rod and the adapter together. After screwing, the countersunk through hole and the internal thread hole are positioned opposite each other and are tightened by screwing in a cross-slot set screw.

[0008] Furthermore, the main rod is made of titanium alloy, and the internal thread of the front cavity adopts a trapezoidal thread design; the total length L and diameter D of the main rod, the total length L1 and diameter D1 of the front cavity, L1 is 0.25 times to 0.4 times L, and D1 is 0.6 times to 0.8 times D.

[0009] Furthermore, the adapter is provided with an end face pattern and three internal threaded holes at the front end, and three stepped holes are provided on the cutter body. The three stepped holes form a triangle and are respectively opposite to the positions of the three internal threaded holes. Three hexagonal bolts pass through the three stepped holes and are screwed into the corresponding three internal threaded holes to connect the cutter body and the adapter into one unit.

[0010] Furthermore, a forming blade cavity and a forming blade fixing threaded hole are provided on the cutter head body. After the forming blade is installed into the forming blade cavity, the cross-slot fixing screw is screwed into the forming blade fixing threaded hole to secure the forming blade in the forming blade cavity.

[0011] Furthermore, the forming insert is a standard boring insert.

[0012] Furthermore, the high-density mass block is made of tungsten-nickel-iron alloy material, and the inner and outer corrugated tubes are formed by laser welding of disc-type 316L stainless steel. The two ends of the outer corrugated tube are laser welded to the front end of the high-density mass block and the baffle, respectively, and the two ends of the inner corrugated tube are laser welded to the rear end of the high-density mass block and the small baffle, respectively.

[0013] Furthermore, the damping fluid is polydimethyl silicone oil.

[0014] Furthermore, the outer diameter of the outer corrugated pipe is D3, the outer diameter of the front end of the baffle and the high-density mass block is D2, the diameter of the front cavity is D1, D2-D3=0.2mm, and D1-D2=0.1mm.

[0015] The beneficial effects of this utility model are:

[0016] The bellows-type damping vibration damping boring bar disclosed in this utility model uses a bellows, a high-density mass block, and damping fluid as the vibration damping unit, replacing the traditional vibration damping unit composed of a rubber ring, a high-density mass block, and damping fluid. Assembly and operation are simple, disassembly is convenient, and stability and reliability are guaranteed. It fully utilizes the excellent vibration isolation and buffering performance of the bellows, achieving a vibration absorption rate of 85%-90%, and significantly optimizing vibration damping performance.

[0017] The advantages of using stainless steel corrugated pipes are as follows:

[0018] 1. Improved vibration reduction effect: The special structure of the corrugated pipe can effectively absorb and disperse vibration energy, reduce equipment vibration and noise, and improve equipment stability and operating efficiency.

[0019] 2. Extended service life: The stainless steel material and optimized structural design significantly improve the wear resistance and fatigue resistance of the bellows, making its service life 2-3 times that of rubber rings.

[0020] 3. Enhanced high-temperature resistance: Stainless steel performs well in high-temperature environments, is not easily softened or failed, and when combined with high-temperature damping fluid, the bellows damper can withstand temperatures up to 300℃, making it especially suitable for processing difficult-to-machine materials such as titanium alloys and high-temperature alloys.

[0021] 4. Reduced maintenance costs: Reduced frequency of replacement and maintenance, resulting in lower overall maintenance costs. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of the vibration-damping boring bar disclosed in this utility model;

[0023] Figure 2 This is a schematic diagram of the assembly structure of the vibration damping boring bar disclosed in this utility model;

[0024] Figure 3This is a schematic cross-sectional view of the overall structure of the vibration damping boring bar disclosed in this utility model;

[0025] Figure 4 This is a cross-sectional schematic diagram of the main rod in the vibration-damping boring bar disclosed in this utility model;

[0026] Figure 5 This is a cross-sectional schematic diagram of the bellows damper in the vibration-damping boring bar disclosed in this utility model;

[0027] Figure 6-1 This is a partial cross-sectional schematic diagram (I) of the adapter joint in the vibration damping boring bar disclosed in this utility model;

[0028] Figure 6-2 This is a partial cross-sectional schematic diagram (II) of the adapter joint in the vibration damping boring bar disclosed in this utility model;

[0029] Figure 7 This is a schematic diagram of the internal hexagonal adjusting screw in the vibration damping boring bar disclosed in this utility model;

[0030] Figure 8 This is a schematic diagram of the cutter head body in the vibration-damping boring bar disclosed in this utility model.

[0031] Figure label:

[0032] 1-Hexagonal bolt, 2-Forming blade, 3-Phillips head screw, 4-Tool body, 41-Stepped hole, 42-Forming blade cavity, 43-Forming blade threaded hole, 45-Triangle, 5-Hexagonal adjusting screw, 51-Hexagonal groove, 52-External thread, 6-Spring, 7-Adapter, 71-Internal threaded hole, 72-Internal thread, 73-External thread, 74-Spring cavity, 75-Guide hole, 76-Internal threaded hole, 77-End face texture, 8-Bellowed damper, 81-High-density mass block, 82-Outer bellows, 83-Damping fluid, 84-Inner bellows, 85-Small baffle, 86-Baffle, 87-Laser welding, 88-Damping fluid through hole, 89-Guide rod, 9-Main rod, 91-Front end cavity, 92-Counterhead through hole, 93-Internal thread, 10-Phillips head set screw. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0034] Example 1, as Figure 1-3As shown, this embodiment discloses a bellows-type damping and vibration-damping boring bar to replace the traditional rubber ring-type vibration-damping tool bar. It includes a main rod 9, an adapter 7 installed at the front end of the main rod, a tool head body 4 installed at the front end of the adapter 7, and a forming insert 2 installed on the tool head body. In this embodiment, the forming insert is a standard boring insert.

[0035] A bellows damper 8 is installed in the front cavity of the main rod. The bellows damper includes a high-density mass block and a baffle. The outer diameter of the front end of the high-density mass block is larger than that of the rear end. This variable diameter design can ensure the timely transmission of radial disturbances.

[0036] like Figure 5 As shown, the front end of the high-density mass block 81 is connected to the rear end baffle 86 via an outer corrugated pipe 82. The outer corrugated pipe is filled with damping fluid 83 and a small baffle 85 is provided. In this embodiment, the damping fluid is polydimethyl silicone oil, which has excellent thermal stability and aging resistance, and is widely used in high-temperature environments. Of course, other high-temperature damping fluids can also be used. The rear end of the high-density mass block is connected to the small baffle via an inner corrugated pipe 84. A damping fluid through-hole 88 is provided on the small baffle. A guide rod 89 is provided at the front of the high-density mass block. A guide hole 75 and a spring cavity 74 are provided in the middle of the adapter. The guide rod passes through the guide hole and is inserted into the spring cavity. An internal thread 72, a hexagonal adjusting screw 5, and a spring 6 are provided in the spring cavity. The hexagonal adjusting screw is screwed onto the internal thread and abuts against the guide rod. The hexagonal adjusting screw can move back and forth along the internal thread within the spring cavity, and the spring abuts against the hexagonal adjusting screw. The position of the high-density mass block can be changed within a certain range by adjusting the hexagonal adjusting screw, thus expanding the applicable range of this vibration-damping boring bar within a certain adjustment range. The spring provides an appropriate preload to the hexagonal adjusting screw to prevent loosening during vibration and improve reliability. Note that the spring compression should not cause the small baffle to adhere to the baffle plate, resulting in poor flow of the damping fluid.

[0037] like Figure 4 As shown, an internal thread 93 is provided at the front of the cavity 91 at the front end of the main rod 9, and three countersunk through holes 92 are provided on the internal thread, as shown. Figure 6-1 As shown, an external thread 73 is provided at the rear end of the adapter 7, and three internal threaded holes 76 are provided on the external thread. The internal thread of the cavity at the front end of the main rod mates with the external thread at the rear end of the adapter, allowing the main rod and the adapter to be screwed together. After screwing, the positions of the three countersunk holes and the three internal threaded holes are aligned. A cross-shaped set screw 10 is screwed into each countersunk hole to secure the countersunk hole and the corresponding internal threaded hole together. Tightening the adapter provides appropriate preload to the outer bellows of the bellows damper.

[0038] The main rod is made of low-density, high-specific-strength titanium alloy, which reduces vibration and improves machining accuracy during high-speed processing. The internal thread of the front cavity adopts a trapezoidal thread design, which has strong self-locking and high load-bearing capacity. The total length L and diameter D of the main rod, and the total length L1 and diameter D1 of the front cavity are as follows: L1 is generally 0.25 to 0.4 times L, and D1 is generally 0.6 to 0.8 times D. The specific values ​​are determined according to the material of the main rod. The general principle is that the cavity structure should not significantly reduce the static stiffness of the main rod.

[0039] like Figure 6-2 As shown, the front end of the adapter is provided with an end face pattern 77 and three internal threaded holes 71, and the cutter head body is provided with three stepped holes 41. Based on the stability of triangles, the three stepped holes form a triangle 45 and are respectively opposite to the positions of the three internal threaded holes. Three hexagonal bolts 1 pass through the three stepped holes and are screwed into the corresponding three internal threaded holes to connect the cutter head body and the adapter as one unit.

[0040] When it is necessary to adjust the vibration reduction parameters, simply unscrew the three hex bolts mentioned above, remove the cutter head body from the adapter, and then adjust the position of the high-density mass block by adjusting the hex bolts to adjust the vibration reduction parameters. This does not require disassembling and assembling multiple parts, making the operation simple and convenient.

[0041] like Figure 7 As shown, an external thread 52 and a hexagonal groove 51 are provided on the internal hexagonal adjusting screw 5.

[0042] like Figure 8 As shown, a forming blade cavity 42 and a forming blade fixing threaded hole 43 are provided on the cutter head body 4. After the forming blade is installed into the forming blade cavity, the cross-slot fixing screw 3 is screwed into the forming blade fixing threaded hole to secure the forming blade in the forming blade cavity.

[0043] The high-density mass block is made of high-density, high-thermal-conductivity tungsten-nickel-iron alloy material. The inner and outer corrugated tubes are formed by laser welding of disc-type 316L stainless steel, which has excellent corrosion resistance, flexibility, and vibration resistance. The two ends of the outer corrugated tube are laser-welded to the front end of the high-density mass block and the baffle 87, respectively, while the two ends of the inner corrugated tube are laser-welded to the rear end of the high-density mass block and the small baffle 87, respectively.

[0044] The outer bellows has an outer diameter of D3, while the front-end outer diameters of the baffle and the high-density mass block are both D2. The diameter of the front-end cavity is D1. The radial clearance between the outer bellows and the front ends of the baffle and the high-density mass block is 0.2 mm, i.e., D2-D3=0.2 mm, ensuring that the outer bellows can freely expand and contract. The radial clearance between the front ends of the baffle and the high-density mass block and the front-end cavity is 0.1 mm, i.e., D1-D2=0.1 mm, which ensures both the adjustment clearance of the high-density mass block and provides support for the outer bellows.

[0045] The vibration damping principle of the vibration damping boring bar disclosed in this utility model is as follows: the axial disturbance force generated by the vibration damping boring bar acts on the outer bellows through the front end of the high-density mass block. The outer bellows undergoes axial deformation, providing the elastic restoring force required for vibration isolation. The vibration energy transmitted to the baffle is rapidly reduced, and the axial vibration absorption effect is improved. The high-density mass block adopts a variable diameter design, which can promptly transmit the radial disturbance force generated by the vibration damping boring bar to the high-density mass block. Through the high-frequency vibration of the high-density mass block, the damping fluid is compressed, converting the radial vibration mechanical energy into the heat / internal energy of the damping fluid. The damping fluid in the outer bellows increases in volume after being heated and enters the inner bellows through the damping fluid through-hole. The inner bellows is in a free state and can deform with the change in the volume of the damping fluid, playing a role in volume compensation and dissipating the energy of the damping fluid, thereby achieving the purpose of vibration damping.

[0046] The key data comparison between the vibration damping boring bar disclosed in this utility model and the previous rubber ring type vibration damping boring bar is as follows:

[0047]

[0048]

[0049] In summary, the bellows-type damping boring bar disclosed in this utility model overcomes the shortcomings of the traditional rubber ring type damping boring bar, and has the advantages of significant vibration reduction effect, long service life, high temperature resistance and low maintenance cost. It has broad prospects and important practical significance in the field of boring machining.

Claims

1. A bellows-type damping vibration reduction boring bar, characterized in that: The system includes a main rod, an adapter joint installed at the front end of the main rod, a cutter head body installed at the front end of the adapter joint, a shaped blade installed on the cutter head body, and a bellows damper installed in the front cavity of the main rod. The bellows damper includes a high-density mass block and a baffle. The outer diameter of the front end of the high-density mass block is larger than that of the rear end. The front end of the high-density mass block is connected to the baffle at its rear end through an outer bellows. The outer bellows is filled with damping fluid and a small baffle is installed. The rear end of the high-density mass block is connected to the small baffle through an inner bellows. A damping fluid through hole is provided on the small baffle. A guide rod is installed at the front of the high-density mass block. A guide hole and a spring cavity are provided in the middle of the adapter joint. The guide rod passes through the guide hole and is inserted into the spring cavity. An internal hexagonal adjusting screw and a spring are installed in the spring cavity. The internal hexagonal adjusting screw abuts against the guide rod and can move back and forth along the spring cavity. The spring abuts against the internal hexagonal adjusting screw.

2. The bellows-type damping vibration reduction boring bar according to claim 1, characterized in that: An internal thread is provided at the front of the cavity of the main rod, and a countersunk through hole is provided on the internal thread. An external thread is provided at the rear of the adapter, and an internal thread hole is provided on the external thread. The internal thread of the cavity at the front of the main rod and the external thread at the rear of the adapter can be matched to screw the main rod and the adapter together. After screwing, the countersunk through hole and the internal thread hole are positioned opposite each other and are tightened by screwing in a cross-slot set screw.

3. The bellows-type damping vibration reduction boring bar according to claim 2, characterized in that: The main rod is made of titanium alloy, and the internal thread of the front cavity adopts a trapezoidal thread design; the total length L and diameter D of the main rod, the total length L1 and diameter D1 of the front cavity, L1 is 0.25 times to 0.4 times L, and D1 is 0.6 times to 0.8 times D.

4. The bellows-type damping vibration reduction boring bar according to claim 1, characterized in that: The adapter has a textured surface and three internal threaded holes at the front end. The cutter head has three stepped holes. The three stepped holes form a triangle and are respectively opposite to the three internal threaded holes. Three hexagonal bolts pass through the three stepped holes and are screwed into the corresponding three internal threaded holes to connect the cutter head and the adapter into one unit.

5. The bellows-type damping vibration reduction boring bar according to claim 1, characterized in that: A forming blade cavity and a forming blade fixing threaded hole are provided on the cutter head body. After the forming blade is installed into the forming blade cavity, the cross-slot fixing screw is screwed into the forming blade fixing threaded hole to secure the forming blade in the forming blade cavity.

6. The bellows-type damping vibration reduction boring bar according to claim 1, characterized in that: The forming insert is a standard boring insert.

7. The bellows-type damping vibration reduction boring bar according to claim 1, characterized in that: The high-density mass block is made of tungsten-nickel-iron alloy. The inner and outer corrugated tubes are formed by laser welding of disc-type 316L stainless steel. The two ends of the outer corrugated tube are laser welded to the front end of the high-density mass block and the baffle, respectively. The two ends of the inner corrugated tube are laser welded to the rear end of the high-density mass block and the small baffle, respectively.

8. The bellows-type damping vibration reduction boring bar according to claim 1, characterized in that: The damping fluid is polydimethyl silicone oil.

9. The bellows-type damping vibration reduction boring bar according to claim 1, characterized in that: The outer diameter of the outer corrugated pipe is D3, the outer diameter of the front end of the baffle and the high-density mass block is D2, the diameter of the front cavity is D1, D2-D3=0.2mm, D1-D2=0.1mm.

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