A multi-blade staggered tooth inner chip removal deep hole drill bit drilling force decoupling device and decoupling method

Abstract

This invention discloses a drilling force decoupling device and method for multi-tooth staggered internal chip removal deep hole drill bits, belonging to the field of deep hole machining cutting detection technology. The device is built on a conventional CNC milling machine and adopts a test mode of specimen rotation and tool fixation. It mainly includes: a three-dimensional force measuring platform and signal acquisition unit, a load-bearing cutting oil supply and chip removal base, a coaxial tool holder, a pre-treated drill bit, a cutting oil sealing container, a specimen, and a tool holder clamping a deformation-resistant thin-walled cylinder specimen. By collecting and processing data from each drilling stage, and utilizing staged drilling and differential calculation, the cutting force component of the cutting edge and the guiding block action component are quantitatively separated, achieving decoupling of the multi-cutting edge cutting force and the guiding block action force. This invention has advantages such as compact device structure, low cost, and strong repeatability, and can significantly improve the accuracy and efficiency of deep hole drilling tool development, machining mechanism research, and engineering application optimization.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of metal cutting and tool performance detection, and specifically relates to a multi-edge staggered-tooth inner-removal deep hole drill drilling force decoupling device and decoupling method, which can be applied to tool performance testing in the deep hole drilling working condition of a pressure vessel tube plate, and is suitable for deep hole drilling force detection scenes in the fields of energy equipment, aerospace, engineering machinery and the like. BACKGROUND

[0002] In the machining process of the multi-edge staggered-tooth inner-removal deep hole drill, the combined action of the cutting edges removing material and the guide blocks extruding the hole wall produces a hole diameter expansion, and the hole diameter expansion and the drill diameter jointly determine the drilled hole diameter. The combined action of cutting and extrusion of this type of drill can significantly improve productivity and machining quality, and is suitable for drilling thousands of large-length-diameter-ratio and high-precision tube holes on a pressure vessel tube plate, and can complete deep hole drilling of a tube plate composed of a surfacing layer and a base material layer at one time. As can be seen, the drilling force and its distribution on the cutting edges and the guide blocks have a direct impact on drilling quality and process stability.

[0003] The multi-edge staggered-tooth inner-removal deep hole drill adopts a multi-cutting edge staggered tooth distribution design of outer edges, middle edges and inner edges, and the cutting edges are arranged in order according to the axial position of the drill, and are in contact with the hole wall to realize positioning and guidance in cooperation with the two guide blocks. The guide blocks are made of hard alloy material, and the surface is polished, which cooperates with the cutting edges to form a "cutting-guiding" integrated structure. The tool body has a through hollow inner cavity as a chip removal channel, and the shank portion is provided with threads for connecting with a drill rod, and the specific structure is shown in Figure 1 .

[0004] The machining principle is as follows: during drilling, the outer edges, the middle edges and the inner edges are in contact with the workpiece in order according to the axial position, and gradually remove the material. When the guide blocks enter the hole formed by the cutting edges, a combined machining state of "cutting edge removing material + guide block extruding hole wall" is formed, the radial force generated by the asymmetric cutting edge is transmitted to the hole wall through the guide block, the guide block extrudes and trims the hole wall, thereby improving the drilling quality. The cutting oil supply device supplies high-pressure cutting oil to the cutting edges through the annular gap between the inside of the guide sleeve and the outside of the drill rod, the cutting oil reversely presses the chips into the hollow inner cavity of the drill, and the chips are discharged backward through the chip removal channel formed by the drill and the drill rod. The cutting oil is filtered through the filter screen and then returns to the oil tank for recycling, as shown in Figure 2 The combined action of the multi-cutting edge removing material, the guide block extruding the hole wall and the cutting oil cooling and chip removal can improve the machining efficiency, improve the hole machining quality and reduce the tool wear, and is suitable for deep hole drilling of difficult-to-machine materials.

[0005] The machining process is as follows: the drill drilling into the hole is divided into five main stages, as shown in Figure 3Stage one is the undrilling stage, the drill bit rotates in the guide sleeve, but does not contact the test piece. The idle torque and idle feed force generated by the friction between the drill bit and the guide sleeve, the machine tool and the cutting oil pressure are 0 and 0 respectively. In stage two, the outer edge, the middle edge and the inner edge are in contact with the test piece in turn according to the axial position, and the material is gradually removed. At the end of stage two, the torque and feed force generated by each cutting edge cutting the test piece are 1 and 1 respectively. Stage three is the guide block entering stage, the front end of the guide block contacts the hole wall formed by the cutting edge and extrudes the hole wall, forming the peak value of torque and feed force. Stage four is the stable drilling stage, after the guide block enters the hole formed by the cutting edge, the combined machining state of "cutting edge removing material + guide block extruding hole wall" is formed. The torque and feed force of the stable drilling stage are 2 and 2 respectively, and the subsequent stage five is the drilling out stage, the torque and feed force gradually decrease. T F T F T F

[0006] Therefore, the drilling force in the stable drilling stage not only includes the cutting force generated by the cutting edge, but also includes the extrusion force and friction force between the guide block and the hole wall (i.e. the guide block acting force). It is necessary to decouple these torque and force values, and accurately measure the difference between 2 and 2 and 1 and 1, which is used for tool development, mechanism research and process optimization. T F T F

[0007] The existing technology for drilling force measurement and decoupling of the multi-edge staggered tooth inner-removal deep hole drill has the following deficiencies: First, the force value decoupling is difficult. The existing measurement scheme can generally only realize the overall collection of the drilling force, and cannot directly effectively decouple the cutting force generated by the cutting edge and the guide block acting force, which makes it difficult to support tool structure optimization and in-depth research on drilling mechanism.

[0008] Second, the test threshold is high and the cost is large. The existing test scheme mostly relies on large deep hole drilling machines and special force sensors, which has high equipment investment, complex installation and debugging, and needs to be matched with large-size test pieces and a large number of special tooling, so it is difficult to carry out batch and repetitive tests in a conventional machine tool or laboratory environment.

[0009] Third, the measurement accuracy and standardization degree are insufficient. The test is carried out by using a conventional clamping scheme that is not optimized for force measurement, which easily introduces interference such as clamping deformation and cutting vibration, reducing the measurement stability. At the same time, there is no standardized drilling force decoupling test process for this type of drill, which restricts the efficiency of tool development and process optimization. SUMMARY

[0010] ​​​​​​​​​​Therefore, in order to solve the problem that the cutting force of the cutting edge and the force of the guide block are difficult to decouple in the drilling process of the multi-edge staggered tooth internal chip removal deep hole drill bit, a drilling force decoupling device and a decoupling method which can be built on a conventional numerical control machine tool are provided. The present application can quantitatively separate the cutting force component of the cutting edge and the action component of the guide block, and the device structure is compact, the test cost is low, the measurement stability and the data reliability are high, and the present application can provide data support for deep hole drilling tool research and development, machining mechanism research and engineering process optimization.

[0011] To achieve the above object, the present application adopts the following technical scheme: a multi-edge staggered tooth internal chip removal deep hole drill bit drilling force decoupling device, comprising: A three-dimensional force platform and a signal acquisition unit are fixedly installed on the workbench of the numerical control machine tool, and are used for synchronously collecting cutting forces in X, Y and Z three orthogonal directions; A force type cutting oil supply and chip removal base is arranged above the three-dimensional force platform and the signal acquisition unit, and has the functions of cutting force rigid transmission, cutting oil supply and oil chip discharge; A coaxial tool holder is fixed at the center position of the force type cutting oil supply and chip removal base, and is used for clamping the pretreated drill bit; The pretreated drill bit is based on a standard multi-edge staggered tooth internal chip removal deep hole drill bit, and the large positioning table, the small positioning table and the fastening thread of the original drill body tail are cut off, and the complete staggered tooth cutting structure and the guide structure are retained; A cutting oil sealed container is arranged outside the cutting area of the pretreated drill bit and the test piece, and forms a high-pressure cutting oil sealed cavity; A deformation-resistant thin-walled cylinder test piece clamping handle is connected with the taper hole of the numerical control machine tool spindle through cooperation, and the lower end is fixed with the test piece.

[0012] The force type cutting oil supply and chip removal base comprises a base, a No. 1 shaft shoulder screw, a cutting oil input pipeline, a cutting oil and chip discharge pipeline and an oil-proof plate; The base is fixed on the three-dimensional force platform and the signal acquisition unit through the No. 1 shaft shoulder screw, and is fixed on the oil-proof plate through the No. 2 shaft shoulder screw; The oil-proof plate is integrally installed with the cutting oil input pipeline and the cutting oil and chip discharge pipeline.

[0013] Preferably, the No. 1 shaft shoulder screw and the No. 2 shaft shoulder screw have a shaft shoulder structure, which cooperates with the bolt holes of the base and the oil-proof plate to realize accurate axial positioning between components during assembly, and simultaneously bear the lateral load during drilling.

[0014] Preferably, the coaxial tool holder comprises a holder base, the pretreated drill bit and the holder base are welded as a whole, and after tool setting, the drill bit axis is ensured to coincide with the rotation center of the machine tool spindle.

[0015] Preferably, the cutting oil sealing container includes a sealing container and a sealing ring. The sealing container is made of transparent material, with the bottom sealed and installed on the oil-proof plate, and a through hole opened at the top and a sealing ring installed thereon. The inner diameter of the sealing ring is clearance-fitted with the outer diameter of the tool holder used to clamp the test piece, forming a rotary dynamic sealing structure.

[0016] Preferably, the specimen adopts a columnar or thin-walled cylindrical structure to simulate the stress state of the workpiece in actual deep hole machining. It can simulate a single material or a double-layer structure. The double-layer structure includes a specimen surface layer and a specimen base layer, which is used to simulate the drilling force characteristics of composite materials or coating materials, and realize the decoupled analysis of drilling forces of different materials.

[0017] A method for decoupling drilling force in a multi-tooth internal chip-removing deep hole drill bit, based on the aforementioned decoupling device, includes the following steps: Step 1: Test preparation and device calibration: Install each component and perform tool setting operation to make the axis of the pre-treated drill bit coincide with the rotation center of the machine tool spindle. Perform static calibration and initialization debugging on the three-dimensional force measuring platform. Step 2: Acquisition of no-load reference force: Start the machine tool spindle to drive the specimen to rotate at idle, turn on the cutting oil supply system, and collect the no-load torque T0 and the no-load feed force F0; Step 3: Staged drilling and data acquisition: Force data acquisition is completed sequentially for the cutting edge stage and the combined cutting-extrusion stabilization drilling stage; Step 4: Test signal processing: Subtract the no-load reference force from the force values ​​measured at each stage to eliminate friction and oil pressure interference and obtain the corrected actual drilling force; Step 5: Drilling force decoupling calculation: By calculating the difference between the two stages of drilling force, the guide block force generated by the interaction between the guide block and the hole wall is separated.

[0018] Preferably, the cutting stage involves the outer edge, intermediate edge, and inner edge sequentially cutting into the specimen material. Torque is collected when all cutting edges are fully engaged in cutting and the two guide blocks have not yet contacted the machined hole wall. T 1. Feed force F 1. Radial force F cr and tangential force F ct ; The cutting-extrusion combined stabilization drilling stage is characterized by the guide block fully conforming to the hole wall and the drilling force fluctuations stabilizing after which torque is collected. T 2 and feed force F 2.

[0019] Preferably, in step 4: Torque generated during the cutting stage of the cutting edge M c = T 1-T 0, feed force F cf = F 1- F 0; Torque generated during the stabilization drilling phase M = T 2- T 0, feed force F f = F 2- F 0.

[0020] Preferably, in step 5: Torque generated by the action of the guide block MP = T 2- T 1. Feeding force generated by the guide block FP f = F 2- F 1.

[0021] Set the ratio of the torque generated by the force of the guide block to the cutting torque of the cutting edge. p = MP / M c The ratio of the feed force generated by the guide block to the cutting feed force of the cutting edge. q = FP f / F cf .

[0022] Set the tangential force on the guide block FP tk , supply force FP fk and normal force FP nk Through coefficients μ and μ L Related, μ= FP tk / FP nk , μ L = FP fk / FP nk k=1 and k=2 correspond to the first and second guide blocks, respectively; Based on the radial force balance relationship, the equations are formulated and solved to obtain the tangential forces on the two guide blocks. FP t1 and FP t2 Then the normal force of each guide block can be calculated.FP n1 , FP n2 He Jin Geli FP f1 , FP f2 .

[0023] Preferably, in step 5: the radial force balance equation is:

[0024] in, α , β These are the included angles between the first and second guide blocks and the outer rake face, respectively.

[0025] Preferably, by replacing the drill bit with one of different diameters, different cutting edges and guide block geometry parameters, or by adjusting the drilling process parameters, steps 1 to 5 are repeated to complete the drilling force decoupling test under multiple working conditions and multiple parameters.

[0026] Compared with the prior art, the beneficial effects of the drilling force decoupling device and decoupling method for a multi-tooth internal chip removal deep hole drill bit described in this invention are: 1. High accuracy of force decoupling. Through staged drilling and differential calculation, the cutting force of the cutting edge and the force of the guide block can be quantitatively separated, solving the problem that existing technologies can only measure the overall drilling force, and providing a quantitative basis for tool development and mechanism research.

[0027] 2. The device has strong versatility. It can be built on conventional CNC machine tools without relying on large-scale special deep hole drilling machines. The device has a compact structure, is easy to clamp and debug, greatly reduces the testing cost, and facilitates batch and repetitive testing.

[0028] 3. Good measurement stability. The "sample rotation, tool fixation" layout, combined with pre-treated drill bits, rigid connection structure and anti-deformation clamping design, effectively reduces cutting vibration and clamping deformation interference, the force transmission path is clear and the data repeatability is strong.

[0029] 4. High degree of simulation of actual working conditions. The integrated cutting oil supply and internal chip removal structure fully simulate the actual deep hole drilling working conditions, and the test results can be directly used to guide engineering applications.

[0030] 5. Standardized testing process. A complete testing process has been established, from equipment use to force decoupling, which can be adapted to multi-tooth internal chip removal deep hole drills of different specifications, effectively improving the efficiency of tool development and process optimization. Attached Figure Description

[0031] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 A schematic diagram of a multi-tooth internal chip removal deep hole drill bit; Figure 2 A schematic diagram illustrating the drilling principle of a multi-tooth internal chip removal deep hole drill bit. Figure 3 This is a schematic diagram of the main stages of drill bit penetration; Figure 4 This is an assembly diagram of the drilling force decoupling device for the multi-tooth internal chip removal deep hole drill bit described in this invention. Figure 5 Detailed drawings of each part of the drilling force decoupling device; Figure 6 A schematic diagram of the cutting oil inlet pipeline, cutting oil and chip discharge; In the figure: 1. Outer cutting edge; 2. Middle cutting edge; 3. Inner cutting edge; 4. First guide block; 5. Second guide block; 6. Tool body; 7. Large positioning table; 8. Small positioning table; 9. Tool body fastening thread; 11. Cutting oil supply device; 12. Guide sleeve; 13. Specimen surface layer; 14. Specimen base layer; 15. Chip removal channel; 10. Drill rod; 16. Three-dimensional force measuring platform and signal acquisition unit; 17. Load-bearing cutting oil supply and chip removal base; 18. Coaxial tool holder; 19. Pre-treated drill bit; 20. Cutting oil sealing container; 21. Specimen; 22. Anti-deformation thin-walled cylinder specimen clamping tool holder. Base 171, No. 1 shoulder screw 172, cutting oil inlet pipe 173, cutting oil and chip outlet pipe 174, oil shield 175, No. 2 shoulder screw 176; Clamp base 181, No. 3 shaft shoulder screw 182; Sealed container 201, sealing ring 202. Detailed Implementation

[0032] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the drawings, and not all of them. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing specific embodiments only and is not intended to limit the invention.

[0033] See Figures 4-6This embodiment describes a drilling force decoupling device for a multi-tooth internal chip-removing deep hole drill bit. Built on a conventional CNC milling machine, it employs a "rotating specimen, fixed tool" testing mode. By collecting and processing data from each drilling stage, it achieves decoupling of the cutting force of the multiple cutting edges and the force of the guide block. The device mainly includes: a three-dimensional force measuring platform and signal acquisition unit 16, a load-bearing cutting oil supply and chip-removing base 17, a coaxial tool holder 18, a pre-treated drill bit 19, a cutting oil sealing container 20, a specimen 21, and a deformation-resistant thin-walled cylindrical specimen clamping tool holder 22.

[0034] This technical solution adopts a "sample rotation, tool fixation" testing mode. The basic principle is as follows: the sample clamping tool holder 22 is clamped onto the spindle of a conventional CNC machine tool, driving the sample 21 to complete the main rotational motion and axial feed motion. The sample 21 contacts the cutting edge and guide block of the pre-treated drill bit 19 in sequence. The resulting drilling force is rigidly transmitted to the three-dimensional force measuring platform and signal acquisition unit 16 through the coaxial tool holder 18 and the load-bearing cutting oil supply and chip removal base 17, acquiring torque and feed force data for the entire drilling process, which is then used for subsequent force decoupling. During the test, the cutting oil sealing container 20 cooperates with the load-bearing cutting oil supply and chip removal base 17 to construct a complete high-pressure cutting oil supply and internal chip removal circulation path, simulating actual deep hole drilling conditions. The structure and connection relationship of each part of the drilling force decoupling device are shown in [details omitted]. Figure 4 , Figure 5 The details are as follows: The three-dimensional force measuring platform and signal acquisition unit 16 are fixedly installed on the CNC machine tool worktable. They can simultaneously acquire cutting force components in three orthogonal directions: X, Y, and Z. The torque can be calculated by synthesizing the X and Y component forces, and the axial feed force can be obtained by the Z component force. The sampling frequency and measurement accuracy meet the testing requirements of drilling force.

[0035] The load-bearing cutting oil supply and chip removal base 17 is located above the three-dimensional force measuring platform and the signal acquisition unit 16, and has the functions of rigid transmission of cutting force, supply of cutting oil and discharge of oil chips. It includes a base 171, a first shoulder screw 172, a cutting oil input pipeline 173, a cutting oil and chip discharge pipeline 174, an oil shield 175, and a second shoulder screw 176.

[0036] The base 171 is fixed to the three-dimensional force measuring platform and signal acquisition unit 16 at its bottom by six No. 1 shoulder screws 172, and to the oil-proof plate 175 at its top by twelve No. 2 shoulder screws 176. The No. 1 shoulder screws 172 and No. 2 shoulder screws 176 have shoulder structures that mate with the bolt holes of the base 171 and the oil-proof plate 175. The shoulder structure of the screws enables precise axial positioning between components during assembly, while also bearing lateral loads during drilling, ensuring the relative position stability of each connected component, allowing the cutting force to be transmitted to the three-dimensional force measuring platform without loss, and avoiding measurement errors introduced by connection gaps.

[0037] The oil shield 175 integrates a cutting oil inlet pipe 173 and a cutting oil and chip discharge pipe 174. The cutting oil inlet pipe 173 is connected to a high-pressure cutting oil system, directing the cutting oil to the outer periphery of the drill bit. The cutting oil and chip discharge pipe 174 connects to the hollow chip removal channel within the pre-treated drill bit 19, exporting the cutting oil carrying chips to an external filtration and circulation system, fully simulating the high-pressure oil supply and reverse chip removal conditions of actual deep-hole drilling. Figure 6 As shown.

[0038] The coaxial tool holder 18 is fixed at the center of the oil-proof plate 175 of the load-bearing cutting oil supply and chip removal base 17, and includes a holder base 181 and a No. 3 shoulder screw 182. The pre-treated drill bit 19 is welded to the holder base 181 as a whole, and after tool setting, it is ensured that the drill bit axis coincides with the rotation center of the machine tool spindle. The holder base 181 is positioned and connected to the oil-proof plate 175 by the No. 3 shoulder screw 182. The No. 3 shoulder screw 182 has a built-in shoulder positioning structure, which can achieve precise positioning of the holder base 181 and the oil-proof plate 175, ensure the coaxiality of the drill bit and the spindle, and stably transmit lateral cutting loads, avoiding the connection gap from affecting the measurement accuracy.

[0039] The pre-treated drill bit 19 uses a standard multi-tooth staggered-tooth internal chip-removing deep-hole drill bit as its base. The large positioning platform 7, small positioning platform 8, and the screw thread 9 fastening the drill bit body 6 at the tail end are removed, while retaining the complete staggered-tooth cutting structure of the outer cutting edge 1, intermediate cutting edge 2, and inner cutting edge 3, as well as the guiding structure of the first guide block 4 and the second guide block 5. The through-type hollow chip-removing cavity of the drill bit body 6 is also retained. The root of the pre-treated drill bit body is coaxially assembled and welded to the chuck base 181, ensuring that the cutting, guiding, and chip-removing functions of the drill bit are completely consistent with the original industrial drill bit. This also shortens the overall overhang length of the drill bit, adapting to the test installation space, reducing cutting vibration caused by the long overhang, and improving measurement accuracy.

[0040] The cutting oil sealing container 20 includes a sealing container 201 and a sealing ring 202. The sealing container 201 is made of transparent materials such as acrylic and is sealed at the bottom and installed on the oil-proof plate 175, completely accommodating the cutting area of ​​the pre-treated drill bit 19 and the test piece 21 within the internal space. A through hole is opened at the top of the sealing container 201 and a sealing ring 202 is installed thereon. The inner diameter of the sealing ring 202 is clearance-fitted with the outer diameter of the test piece clamping tool holder 22, forming a rotary dynamic seal structure. This allows the test piece clamping tool holder 22 to rotate and axially feed the test piece 21 while preventing high-pressure cutting oil and chips from splashing outwards. The transparent material allows for direct observation of the tool setting process, cutting status, and chip removal, facilitating experimental operation and status monitoring.

[0041] The specimen 21 can be a cylindrical or thin-walled cylindrical structure, with the material consistent with the actual machining conditions. It can simulate a single material or a double-layer structure of the specimen surface layer 13 (weld overlay) + specimen base layer 14 of a pressure vessel tube sheet. The upper end of the specimen clamping tool holder 22 is connected to the taper hole of the CNC machine tool spindle, and the lower end is fixed to the specimen 21 by a spring-loaded clamping structure. The size of the specimen 21 is adapted to the test force range, and the specimen clamping tool holder 22 adopts an anti-deformation structure design to reduce clamping deformation and cutting vibration. Driven by the machine tool spindle, it performs the main rotary motion and axial feed motion, realizing the drilling test mode of "specimen rotation and tool fixation".

[0042] Based on the above decoupling device, the present invention also provides a method for decoupling drilling force of a multi-tooth internal chip-removing deep hole drill bit. By collecting and processing data at each drilling stage, the decoupling of cutting force of multiple cutting edges and force of guide block is achieved. The specific steps are as follows: Step 1: Experimental preparation and apparatus calibration The three-dimensional force measuring platform and signal acquisition unit 16 are horizontally fixed to the CNC machine tool worktable. A load-bearing cutting oil supply and chip removal base 17, a coaxial tool holder 18, and a pre-treated drill bit 19, forming a tool assembly, are then installed sequentially. The cutting oil sealing container 20 and sealing ring 202 are installed, and the external high-pressure cutting oil circulation system is connected and the oil supply pressure is adjusted. The test piece 21 is clamped in the test piece clamping tool holder 22 and then inserted into the machine tool spindle. A tool setting operation is performed to align the axis of the pre-treated drill bit 19 with the rotation center of the machine tool spindle. The three-dimensional force measuring platform is statically calibrated and initialized, and parameters such as the data type and sampling frequency of the signal acquisition unit are set.

[0043] Step 2: Acquisition of no-load reference force Start the machine tool spindle and rotate the specimen 21 and specimen clamping tool holder 22 at the set speed. Turn on the cutting oil supply system to the test set pressure, keep the drill bit out of contact with the specimen, and collect the no-load torque under this condition. T 0 and no-load feed force F 0. This reference force value includes the additional forces generated by machine tool spindle friction, tool holder and seal friction, and cutting oil pressure, and is used to correct for interference in subsequent test data.

[0044] Step 3: Staged Drilling and Data Acquisition The machine tool spindle is controlled to drive the specimen 21 axially at a set drilling speed and feed rate, and the stable drilling force acquisition of the two core stages is completed in sequence: 3.1 Cutting stage of the cutting edge: The end face of the specimen gradually contacts the drill bit. The outer cutting edge 1, the intermediate cutting edge 2, and the inner cutting edge 3 cut into the specimen material in sequence according to their axial positions. When all cutting edges are fully engaged in cutting and the two guide blocks have not yet contacted the machined hole wall, the torque of this stage is collected. T 1. Feed force F 1 and radial forceFcr Tangential force Fct During this stage, only the cutting edge performs the material removal function; the guide block does not squeeze or rub against the hole wall.

[0045] 3.2 Combined Cutting-Extrusion Stabilized Drilling Stage: Continue to control the axial feed of the specimen, allowing the guide block to gradually enter the machined hole wall. Once the guide block is fully in contact with the hole wall and the drilling force fluctuations tend to stabilize, keep the feed and rotation parameters constant, and collect the torque under this stable drilling state. T 2 and feed force F 2. This stage is a combined action of "material removal by the cutting edge + extrusion and trimming of the hole wall by the guide block".

[0046] Step 4: Experimental Signal Processing The collected raw force signals are processed by subtracting the no-load reference force from the force values ​​measured at each stage to eliminate the interference of friction and oil pressure, and the corrected actual drilling force is obtained.

[0047] During the cutting stage, the torque generated by the combined action of the outer cutting edge, intermediate cutting edge, and inner cutting edge. M c = T 1- T 0, feed force F cf = F 1- F 0, radial force F cr and tangential force F ct .

[0048] The torque generated by the combined action of the various cutting edges and guide blocks during the stable drilling phase M = T 2- T 0, feed force F f = F 2- F 0.

[0049] Step 5: Drilling Force Decoupling Calculation By calculating the difference in drilling forces between the two stages, the force generated by the interaction between the guide block and the hole wall, and the torque generated by the guide block can be separated. MP = T 2- T 1. Feeding force generated by the guide block FP f = F 2- F 1.

[0050] Set the ratio of the torque generated by the force of the guide block to the cutting torque of the cutting edge. p =MP / M c The ratio of the feed force generated by the guide block to the cutting feed force of the cutting edge. q = FP f / F cf .

[0051] Set the tangential force on the guide block FP tk , supply force FP fk and normal force FP nk Through coefficients μ and μ L Related, μ= FP tk / FP nk , μ L = FP fk / FP nk k=1 and k=2 correspond to the first and second guide blocks, respectively.

[0052] During drilling, the drill bit is in radial equilibrium, meaning that the resultant force of all forces acting on the drill bit parallel to and perpendicular to the outer rake face is zero, as shown in the following equation:

[0053] in, α , β These are the included angles between the first and second guide blocks and the outer rake face, respectively.

[0054] The tangential forces on the two guide blocks were calculated. FP t1 and FP t2 for:

[0055] In the formula C 1 、C 2 、C 3 are respectively:

[0056] Further obtain the guide block coefficient μ and μ L for:

[0057] Further, the normal forces of the first and second guide blocks are obtained.FP n1 , FP n2 He Jin Geli FP f1 , FP f2 :

[0058]

[0059] Complete data acquisition and decoupling, that is, obtain the cutting edge torque through data acquisition. M c , supply force F cf radial force F cr Tangential force F ct The tangential force generated by the compression action on the two guide blocks was obtained through decoupling calculation. FP tk , supply force FP fk and normal force FP nk k=1 and k=2 correspond to the first and second guide blocks, respectively.

[0060] Furthermore, drill bits with different diameters, cutting edges, and guide block geometry can be replaced, or drilling process parameters can be adjusted. Steps 1 to 5 above can be repeated to complete the drilling force decoupling test under multiple working conditions and parameters, providing data support for tool structure optimization, drilling mechanism research, and process parameter adaptation.

[0061] This invention can perform tests that originally required large deep hole drilling machines on ordinary machine tools. This invention has the advantages of compact device structure, low cost, and strong repeatability, which significantly improves the accuracy and efficiency of deep hole drilling tool research and development, machining mechanism research and engineering application optimization.

[0062] The embodiments of the present invention disclosed above are merely illustrative of the invention. These embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention.

Claims

1. A drilling force decoupling device for a multi-tooth internal chip removal deep hole drill bit, characterized in that: include: The three-dimensional force measuring platform and signal acquisition unit (16) are fixedly installed on the CNC machine tool worktable to synchronously acquire the cutting force components in the three orthogonal directions of X, Y, and Z. The load-bearing cutting oil supply and chip removal base (17) is set above the three-dimensional force measuring platform and the signal acquisition unit (16), and has the functions of rigid transmission of cutting force, supply of cutting oil and removal of oil chips. The coaxial tool holder (18) is fixed at the center of the load-bearing cutting oil supply and chip removal base (17) and is used to hold the pre-treated drill bit (19). The pre-treated drill bit (19), the pre-treatment includes the machining of the drill bit tail structure; A cutting oil sealing container (20) is placed outside the cutting area of ​​the pretreated drill bit (19) and the test piece (21) to form a high-pressure cutting oil sealing cavity; The anti-deformation thin-walled cylinder specimen is clamped with a tool holder (22), the upper end of which is connected to the taper hole of the CNC machine tool spindle, and the lower end is fixed to the specimen (21).

2. The drilling force decoupling device for multi-tooth internal chip removal deep hole drill bits according to claim 1, characterized in that, The load-bearing cutting oil supply and chip removal base (17) includes a base (171), a cutting oil inlet pipe (173), a cutting oil and chip discharge pipe (174), and an oil shield (175). The load-bearing cutting oil supply and chip removal base (17) is fixed to the three-dimensional force measuring platform and signal acquisition unit (16) by shoulder screws with a shoulder structure, so as to achieve precise positioning between components and bear lateral loads. The cutting oil input pipeline (173) and the cutting oil and chip discharge pipeline (174) are integrated and installed on the oil shield (175).

3. The drilling force decoupling device for multi-tooth internal chip removal deep hole drill bits according to claim 1, characterized in that, The coaxial tool holder (18) includes a holder base (181). The pre-treated drill bit (19) is welded to the holder base (181) to eliminate the relative displacement between the drill bit and the holder, and to ensure that the drill bit axis coincides with the rotation center of the machine tool spindle after tool setting, thereby reducing radial force interference and improving decoupling accuracy.

4. The drilling force decoupling device for multi-tooth internal chip removal deep hole drill bits according to claim 2, characterized in that, The cutting oil sealing container (20) includes a sealing container (201) and a sealing ring (202). The sealing container (201) is made of transparent material, and the bottom is sealed and installed on the oil-proof plate (175). The top has a through hole and the sealing ring (202) is installed. The inner diameter of the sealing ring (202) is clearance-fitted with the outer diameter of the tool holder (22) of the specimen clamping, forming a rotary dynamic sealing structure.

5. The drilling force decoupling device for multi-tooth internal chip removal deep hole drill bits according to claim 1, characterized in that, The specimen (21) adopts a columnar or thin-walled cylindrical structure to simulate the stress state of the workpiece in actual deep hole machining. The specimen (21) is a single material or a double-layer structure. The double-layer structure includes the specimen surface layer (13) and the specimen base layer (14) to simulate the drilling force characteristics of composite materials or coating materials and realize the decoupled analysis of drilling forces of different materials.

6. A method for decoupling drilling force in a multi-tooth internal chip-removing deep hole drill bit, implemented based on the decoupling device according to any one of claims 1 to 5, characterized in that, Includes the following steps: Step 1: Test preparation and device calibration: Install each component and perform tool setting operation to make the axis of the pre-treated drill bit coincide with the rotation center of the machine tool spindle. Perform static calibration and initialization debugging on the three-dimensional force measuring platform. Step 2: Acquisition of no-load reference force: Start the machine tool spindle to drive the specimen to rotate without load, turn on the cutting oil supply system, and collect the no-load torque. T 0 and no-load feed force F 0; Step 3: Staged drilling and data acquisition: Force data acquisition is completed sequentially for the cutting edge stage and the combined cutting-extrusion stabilization drilling stage; Step 4: Test signal processing: Subtract the no-load reference force from the force values ​​measured at each stage to eliminate friction and oil pressure interference and obtain the corrected actual drilling force; Step 5: Drilling force decoupling calculation: By calculating the difference between the two stages of drilling force, the guide block force generated by the interaction between the guide block and the hole wall is separated.

7. The drilling force decoupling method for multi-tooth internal chip removal deep hole drill bits according to claim 6, characterized in that, In step 3: The cutting stage of the cutting edge is as follows: the outer edge (1), the intermediate edge (2), and the inner edge (3) cut into the specimen material in sequence. When all cutting edges are fully involved in the cutting and the two guide blocks have not yet contacted the machined hole wall, the torque is collected. T 1. Feed force F 1. Radial force F cr and tangential force F ct ; The cutting-extrusion combined stabilization drilling stage is characterized by the guide block fully conforming to the hole wall and the drilling force fluctuations stabilizing after which torque is collected. T 2 and feed force F 2.

8. The drilling force decoupling method for multi-tooth internal chip removal deep hole drill bits according to claim 7, characterized in that, In step 4: Torque generated during the cutting stage of the cutting edge M c = T 1- T 0, feed force F cf = F 1- F 0; Torque generated during the stabilization drilling phase M = T 2- T 0, feed force F f = F 2- F 0.

9. The drilling force decoupling method for multi-tooth internal chip removal deep hole drill bits according to claim 8, characterized in that, In step 5: Torque generated by the action of the guide block MP = T 2- T 1. Feeding force generated by the guide block FP f = F 2- F 1; Set the ratio of the torque generated by the force of the guide block to the cutting torque of the cutting edge. p = MP / M c The ratio of the feed force generated by the guide block to the cutting feed force of the cutting edge. q = FP f / F cf ; Set the tangential force on the guide block FP tk Feeding force FP fk and normal force FP nk Through coefficients μ and μ L Related, μ=FP tk / FP nk , μ L = FP fk / FP nk k=1 and k=2 correspond to the first and second guide blocks, respectively; Based on the radial force balance relationship, the equations are formulated and solved to obtain the tangential forces on the two guide blocks. FP t1 and FP t2 Then the normal force of each guide block can be calculated. FP n1 FP n2 He Jin Geli FP f1 FP f2 .

10. The drilling force decoupling method for multi-tooth internal chip removal deep hole drill bits according to claim 9, characterized in that, In step 5: the radial force balance equation is: in, α , β These are the included angles between the first and second guide blocks and the outer rake face, respectively.

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