Reamer, machine tool and method of use

Abstract

This invention relates to the field of metal cutting tool technology, and in particular to a reamer, a machine tool, and a method of use. The reamer includes: a flange shank for connection to the machine tool spindle; a compensating shank connected to both the flange shank and an adjustable flange, used to move the position of the adjustable flange forward towards the cutting edge to shorten the distance between the cutting edge of the reamer ring and the positioning surface of the adjustable flange; a reamer shank connected to the compensating shank via the adjustable flange; a reamer ring connected to the reamer shank via a positioning structure; multiple insert mounting slots on the reamer ring; indexable inserts installed in the insert mounting slots of the reamer ring; each indexable insert having two indexable cutting tips; and a locking assembly including a double-ended screw and an adjusting expansion pin for tightening the reamer ring and the reamer shank. This invention offers advantages such as improved tool rigidity, reduced cutting deformation, ensured machining accuracy, enabling indexable and replaceable inserts, extended tool life, and reduced machining costs.

Description

Technical Field

[0001] This invention relates to the field of metal cutting tool technology, and in particular to a reamer with a support guide bar for machining large-diameter, long-span holes, a machine tool, and a method of use. Background Technology

[0002] In the manufacturing of high-end equipment such as wind power, aero engines, and heavy industrial machine tools, the machining of large-diameter, long-overhang precision holes is one of the core technological processes. For example, the diameter of the bearing hole in a wind turbine main shaft typically reaches φ200mm-φ500mm, with an overhang length of 400mm-800mm; the diameter of the mounting hole in an aero engine casing reaches φ100mm-φ300mm, with an overhang length of 300mm-600mm; and the diameter of the guide hole in the large worktable of an industrial machine tool reaches φ80mm-φ200mm, with an overhang length of 200mm-500mm. These machining scenarios typically require hole diameter accuracy of IT6-IT7, surface roughness Ra of 0.4μm-0.8μm, and the positional tolerance of the hole system is usually controlled within 0.01mm-0.02mm.

[0003] Currently, in the machining of large-diameter, long-overhanging holes, the reamers used in this field typically employ a composite structure design where a steel tool body is brazed to a cemented carbide insert or a cermet insert. The tool body is usually made of 40Cr or tool steel (elastic modulus approximately 210 GPa), while the insert material is cemented carbide (elastic modulus approximately 600 GPa) or cermet.

[0004] However, the above-mentioned existing technical solutions have the following technical defects:

[0005] 1. Insufficient overall rigidity makes it difficult to control the cutting edge runout.

[0006] When clamped and connected via a hydraulic tool holder (such as HSK-A100 or BT50 interface), the excessive tool overhang (overhang ratio L / D > 5) results in a steel tool body with a much lower elastic modulus than carbide inserts, leading to insufficient overall dynamic rigidity of the reamer. Under cutting force excitation, the tool body exhibits significant bending deformation and chatter, making it difficult to control the radial runout of the reamer cutting edge within 5μm (high-precision reaming typically requires ≤3μm), severely affecting the dimensional accuracy, cylindricity, and surface integrity of the machined hole.

[0007] 2. Cannot be coated, poor wear resistance.

[0008] Furthermore, the difference in thermal expansion coefficients between the blade and the blade body materials is significant (carbide approximately 4.5 × 10⁻⁻⁻⁴). 6 / ℃, steel approximately 11×10⁻ 6High-temperature PVD / CVD coating treatment (temperature 400℃-1000℃) can cause thermal stress concentration at the brazing interface, leading to microcracks or even weld detachment. Therefore, welded reamers typically cannot undergo effective wear-resistant coating post-treatment, and the inserts rely solely on the hardness of the base material. During high-speed cutting (cutting speed Vc > 80m / min) or machining of high-hardness materials (such as wind turbine gear steel 42CrMo4 with a hardness of HB280-HB320 after tempering), the wear rate of the insert's flank face accelerates significantly, reducing tool life by 40%-60%.

[0009] Third, the blades cannot be replaced or indexed, resulting in short tool life and high operating costs.

[0010] More critically, existing welded reamers use permanent brazing connections, meaning the cutting edges cannot be replaced or indexed for reuse. For multi-bladed reamers (typically with 6-12 cutting edges), once any cutting edge chipps, wears excessively, or cracks due to heat, the entire reamer is rendered unusable. Taking the machining of bearing holes for wind turbine main shafts as an example, a single large-diameter welded reamer typically costs between 20,000 and 50,000 yuan, while its actual effective cutting life is only about 30 to 80 pieces. This translates to a single-hole tool cost of 300 to 600 yuan, resulting in extremely low tool life and high operating costs.

[0011] IV. Lack of high-precision modular installation solutions, resulting in poor versatility and complex installation.

[0012] Meanwhile, existing large-diameter reamers lack high-precision solutions for modular installation. Specifically: 1. The tool body and tool holder interface lack a standardized quick-change design, requiring custom-made tool bodies for different machine tool spindle interfaces (such as HSK, KM, Capto, etc.), resulting in poor versatility; 2. The relative position of the tool body and insert cannot be fine-tuned, requiring machine tool spindle precision compensation after installation, leading to complex debugging and long tool setting time (typically 2-4 hours); 3. The lack of a diameter adjustment mechanism means a single reamer can only cover a very narrow range of hole diameters, making it difficult to adapt to the flexible manufacturing needs of multi-variety, small-batch production. These deficiencies further increase manufacturing and operating costs.

[0013] In summary, existing large-diameter reamer technology has systemic defects in areas such as the application of high-rigidity materials, coating process compatibility, tool change / indexing design, modular quick assembly, and diameter adjustment. It is no longer able to meet the comprehensive requirements of high-end equipment fields for large precision hole machining in terms of "high efficiency, high precision, low cost, and flexibility".

[0014] Therefore, there is an urgent need in this field for a new type of reamer structure that can overcome the above-mentioned technical defects. Summary of the Invention

[0015] Therefore, the technical problem to be solved by the present invention is to overcome the problems in the prior art, thereby providing a reamer, a machine tool and a method of using it.

[0016] In a first aspect, a reamer is provided, comprising:

[0017] Flange main handle, used for connection to machine tool spindle;

[0018] The compensating tool holder is connected to the flange main shank and the adjustable flange respectively, and is used to move the position of the adjustable flange forward in the direction of the cutting edge to shorten the distance from the cutting edge of the reamer ring to the positioning surface of the adjustable flange.

[0019] The reamer bar is connected to the compensating tool holder via the adjustable flange;

[0020] A reamer ring is connected to the reamer rod via a positioning structure; the reamer ring is provided with multiple blade mounting slots;

[0021] An indexable insert is installed in the insert mounting slot of the reamer ring; each indexable insert has two indexable cutting tips;

[0022] The locking assembly includes a double-ended screw and an adjusting expansion pin for tensioning the reamer ring to the reamer rod.

[0023] In one embodiment of the present invention, the positioning structure includes a connecting post for the reamer rod and a positioning hole for the reamer ring to mate with the connecting post.

[0024] In one embodiment of the present invention, the connecting post is a 10° hollow short cone, and the positioning hole is a 10° inner short cone hole; after the reamer rod and the reamer ring are locked, they generate radial elastic contraction under the action of locking force, so that the conical surface of the connecting post and the conical hole of the positioning hole form an interference fit; the end face of the reamer ring is in contact with the end face of the reamer rod, forming a double-sided over-positioning of conical surface positioning and end face contact, with a repeatability positioning accuracy ≤3μm.

[0025] In one embodiment of the present invention, a transmission pin is further provided between the reamer ring and the reamer rod; the transmission pin is used to transmit cutting torque.

[0026] In one embodiment of the present invention, a support guide bar is further included, which is detachably disposed on the outer circumferential surface of the reamer ring; the support guide bar is used to form an oil film support with the wall of the machined hole; the number of the support guide bars is 2 to 4, which are evenly distributed along the outer circumference of the reamer ring; the outer diameter of the support guide bar is 0.01 mm to 0.03 mm smaller than the outer diameter of the cutting edge of the reamer ring.

[0027] In one embodiment of the present invention, the adjustable flange is provided with a radial adjustment screw for adjusting the radial runout of the cutting edge.

[0028] In one embodiment of the present invention, the adjusting pin is an eccentric structure. By rotating the adjusting pin, the radial position of the reamer ring relative to the reamer rod can be adjusted, thereby achieving a fine adjustment of the diameter of the reamer ring. The fine adjustment range is ±0.02mm-±0.05mm.

[0029] In one embodiment of the present invention, an internal cooling channel is further provided inside the reamer bar and / or the compensating shank; the internal cooling channel is used to transport a cooling medium; the outlet of the internal cooling channel includes a central internal cooling port and / or a dispersed internal cooling port.

[0030] Secondly, a machine tool is provided, including the reamer described above.

[0031] Thirdly, a method of use is provided, which utilizes the aforementioned reamer, including the following steps:

[0032] Select a reamer ring of the corresponding diameter and a compensating tool holder of the corresponding length based on the hole diameter and hole depth of the workpiece.

[0033] The indexable insert is installed in the insert mounting slot of the reamer ring; the indexable insert has two cutting edges, with the first cutting edge used for the first time;

[0034] The reamer ring is connected to the reamer rod by a positioning structure and locked using a double-ended screw and an adjusting expansion pin.

[0035] Connect the reamer bar to the compensating tool holder via an adjustable flange;

[0036] Connect the compensating tool holder to the flange main shank, and use the radial adjustment screw to adjust the radial runout of the cutting edge to the preset requirement;

[0037] Depending on the machining conditions, install support guide bars on the reamer ring;

[0038] Coolant is delivered to the cutting area through an internal cooling channel;

[0039] Perform reaming machining, maintaining the preset hole tolerance and preset surface roughness during the machining process;

[0040] When the first cutting tip wears out, rotate the indexable insert 180° to use the second cutting tip; when both cutting tips wear out, replace with a new indexable insert.

[0041] Compared with the prior art, the above-described technical solution of the present invention has the following advantages:

[0042] The reamer described in this invention improves tool rigidity by compensating for the shortened distance of the tool holder and enables tool replacement through indexable inserts. It has advantages such as improving tool rigidity, reducing cutting deformation, ensuring machining accuracy, enabling indexable and replaceable inserts, extending tool life, and reducing machining costs. Attached Figure Description

[0043] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0044] Figure 1 This is a schematic diagram of the reamer in this invention;

[0045] Figure 2 This is a schematic diagram of the reamer ring in this invention;

[0046] Figure 3 This is a schematic diagram of the reamer bar, double-ended screw, and adjusting expansion pin in this invention;

[0047] Figure 4 This is a schematic diagram of the flange main handle and the compensating tool holder in this invention.

[0048] Explanation of reference numerals in the instruction manual:

[0049] 10. Flange main handle; 20. Adjustable flange; 30. Compensating tool holder; 40. Reamer rod; 401. Connecting column; 402. Drive pin; 50. Reamer ring; 501. Positioning hole; 502. Support guide bar; 60. Indexable blade; 70. Double-ended screw; 80. Adjusting expansion pin. Detailed Implementation

[0050] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0051] Traditional reamers, when used in high-end equipment manufacturing fields such as wind power, aero-engines, and heavy industrial machine tools to process large-diameter, long-overhang precision holes, generally suffer from the following technical defects: insufficient overall rigidity leading to uncontrollable cutting edge runout; inability to perform coating treatment resulting in poor wear resistance; non-replaceable or non-indexable inserts leading to low tool life and high operating costs; and lack of high-precision modular installation solutions resulting in poor versatility and complex installation.

[0052] In this regard, combined with Figures 1 to 4 This embodiment proposes a reamer that, through a modular component design, aims to improve machining accuracy, extend tool life, and simplify operation.

[0053] The reamer includes a flange shank 10 for connection to a machine tool spindle; a compensating shank 30 connected to both the flange shank 10 and the adjustable flange 20, used to move the position of the adjustable flange 20 forward in the cutting direction to shorten the distance from the cutting edge of the reamer ring 50 to the positioning surface of the adjustable flange 20; a reamer rod 40 connected to the compensating shank 30 via the adjustable flange 20; a reamer ring 50 connected to the reamer rod 40 via a positioning structure, the reamer ring 50 having multiple insert mounting slots; indexable inserts 60 installed in the insert mounting slots of the reamer ring 50, each indexable insert 60 having two indexable cutting tips; and a locking assembly including a double-ended screw 70 and an adjusting expansion pin 80 for tightening the reamer ring 50 to the reamer rod 40.

[0054] For ease of understanding, the following explains some key terms in this embodiment:

[0055] The flange main handle 10 serves to provide a stable connection interface between the reamer and the machine tool spindle, ensuring effective torque transmission and positioning accuracy during the cutting process.

[0056] The adjustable flange 20 serves to provide an installation reference for the connection between the subsequent compensating tool holder 30 and the reamer bar 40, while allowing for a certain degree of adjustment.

[0057] The compensating tool holder 30 is designed to connect with the adjustable flange 20 and, through its structural characteristics, move the position of the adjustable flange 20 forward toward the cutting edge, thereby effectively shortening the distance from the cutting edge of the reamer ring 50 to the positioning surface of the adjustable flange 20 to adapt to different machining requirements.

[0058] The reamer shank 40, as one of the main structures of the reamer, is connected to the compensating tool holder 30 through the adjustable flange 20 and carries the reamer ring 50 to transmit cutting force.

[0059] The reamer ring 50, which serves as the cutting part of the reamer, is connected to the reamer rod 40 through a positioning structure. Multiple blade mounting slots are provided on its outer circumference for mounting indexable blades 60.

[0060] The indexable insert 60, which is the component that actually performs the cutting function, is installed in the insert mounting slot of the reamer ring 50. Each insert is designed with two cutting tips that can be indexed to extend the tool life.

[0061] The locking assembly, consisting of a double-ended screw 70 and an adjusting expansion pin 80, is mainly used to achieve a tight tension connection between the reamer ring 50 and the reamer rod 40, ensuring stability and accuracy during the cutting process.

[0062] This embodiment provides a reamer whose structural design aims to improve machining performance and ease of use.

[0063] Specifically, the reamer includes a flange shank 10, which can be designed with a standardized tapered or straight shank structure, such as an HSK interface, BT interface, or cylindrical straight shank, to facilitate connection with different types of machine tool spindles. The flange shank 10 is fixed to the machine tool spindle by means of mechanical clamping or threaded connection, thereby providing a stable base for the entire reamer system.

[0064] Furthermore, the reamer also includes an adjustable flange 20, which can be assembled with the compensating tool holder 30 by means of threaded connection, pin connection, or key connection. In one implementation, the adjustable flange 20 can be designed to have multiple mounting holes, which are connected to corresponding holes on the compensating tool holder 30 by bolts, thereby fixing the compensating tool holder 30 to the reamer rod 40.

[0065] Based on this, the reamer also includes a compensating shank 30, which is connected to the adjustable flange 20. The compensating shank 30 can be designed with a telescopic structure, for example, by adjusting its length through an internal threaded mechanism. By rotating the adjusting part of the compensating shank 30, its relative position to the adjustable flange 20 can be adjusted, thereby moving the position of the adjustable flange 20 forward in the cutting direction to shorten the distance from the cutting edge of the reamer ring 50 to the positioning surface of the adjustable flange 20. For example, the compensating shank 30 can adopt a multi-segment structure, achieving the compensation function through combinations of connecting segments of different lengths.

[0066] Meanwhile, the reamer 40 is connected to the compensating tool holder 30 via an adjustable flange 20. The reamer 40 can be designed to have a connection end that matches the compensating tool holder 30, for example, by means of threads, tapered fits, or pin fits. In one implementation, the rear end of the reamer 40 can be machined into a shape that conforms to the internal structure of the compensating tool holder 30 and secured with fasteners to ensure a robust connection.

[0067] Furthermore, the reamer ring 50 is connected to the reamer rod 40 via a positioning structure. This positioning structure may include a boss on the reamer rod 40 engaging with a groove on the reamer ring 50, or radial and axial positioning achieved through the engagement of pins and holes. For example, the end of the reamer rod 40 may be machined to have one or more positioning pins, while the inner bore of the reamer ring 50 has positioning holes 501 that match the positioning pins. Through the engagement of these positioning pins and positioning holes 501, the reamer ring 50 is initially positioned on the reamer rod 40. The outer circumference of the reamer ring 50 is provided with multiple blade mounting slots. These mounting slots may be designed with specific geometries, such as dovetail grooves or rectangular grooves, to accommodate the mounting of indexable blades 60 of different shapes.

[0068] Furthermore, the indexable insert 60 is mounted in the insert mounting slot of the reamer ring 50. The indexable insert 60 may be made of materials such as cemented carbide, cermet, or cubic boron nitride. Each indexable insert 60 is designed to have two indexable cutting tips; for example, both ends of the insert have cutting edges. When one cutting tip wears out, the insert can be rotated 180° to continue cutting using the other unworn cutting tip, thereby extending the service life of a single insert.

[0069] Finally, the reamer also includes a locking assembly for tensioning the reamer ring 50 to the reamer shank 40. This locking assembly includes a stud screw 70 and an adjusting expansion pin 80. The stud screw 70 may be designed to pass through a central hole in the reamer shank 40 and engage with a threaded hole inside the reamer ring 50. Tightening the stud screw 70 applies an axial tension force to the reamer ring 50 and the reamer shank 40. The adjusting expansion pin 80 may be placed at the connection interface between the reamer shank 40 and the reamer ring 50. Through its own expansion or eccentricity, it provides radial support or fine-tuning to the connection interface, further enhancing the rigidity and positioning accuracy of the connection. For example, the adjusting expansion pin 80 may be designed with a tapered or threaded structure, generating a radial expansion force within the connection hole through tightening or rotation.

[0070] The reamer provided in this embodiment, through its modular design and the application of indexable inserts, effectively solves the problems of insufficient rigidity, poor wear resistance, short tool life, and complex installation inherent in traditional reamers when machining large-diameter, long-overhang precision holes in fields such as wind power and aero-engines. This reamer enables rapid insert replacement and indexing, significantly improving tool durability and economic efficiency. Simultaneously, its adjustable structure helps optimize cutting performance, meeting the high-precision, high-efficiency machining requirements of high-end equipment manufacturing.

[0071] This embodiment further proposes that the positioning structure includes a connecting post 401 of the reamer rod 40 and a positioning hole 501 for the reamer ring 50 to cooperate with the connecting post 401.

[0072] Specifically, the connecting post 401 is a protruding part on the reamer rod 40, which serves to provide a precise radial and axial positioning reference for the reamer ring 50. The connecting post 401 can be integrally formed onto the reamer rod 40, or it can be manufactured separately and then fixed to the reamer rod 40 by press-fitting, welding, or other methods. Its geometry can be designed as cylindrical, conical, or other shapes with positioning functions according to actual needs to ensure precise fit with the positioning hole 501.

[0073] The positioning hole 501 is a hole opened on the reamer ring 50 corresponding to the position of the connecting post 401, and its inner wall shape matches the outer shape of the connecting post 401. The machining accuracy of the positioning hole 501 directly affects the coaxiality and end face runout of the reamer ring 50 and the reamer rod 40. Therefore, high-precision machining processes, such as grinding or precision boring, are usually adopted to ensure that its dimensional and geometric tolerances meet the requirements. The fitting method between the connecting post 401 and the positioning hole 501 can be selected according to the required connection rigidity and ease of assembly and disassembly. For example, a clearance fit can be used to facilitate assembly, a transition fit can be used to provide a more stable connection, or even an interference fit can be used to achieve higher connection rigidity.

[0074] This embodiment further proposes that the connecting post 401 is a 10° hollow short cone, and the positioning hole 501 is a 10° inner short cone hole; after the reamer rod 40 and the reamer ring 50 are locked, they generate radial elastic contraction under the action of locking force, so that the cone surface of the connecting post 401 and the cone hole of the positioning hole 501 form an interference fit; the end face of the reamer ring 50 is in contact with the end face of the reamer rod 40, forming a double-sided over-positioning of cone surface positioning and end face contact, with a repeatability positioning accuracy ≤3μm.

[0075] Specifically, the connecting post 401 is designed as a short conical structure with a 10° taper angle and is hollow inside. This hollow design helps reduce weight and provides space for internal cooling channels. The 10° taper angle is a commonly used self-locking taper, which can produce good radial positioning and clamping effects under axial locking force, while also facilitating disassembly. The positioning hole 501 is correspondingly designed as a 10° inner short conical hole that matches the connecting post 401, ensuring a tight fit between the two. When the locking assembly applies an axial locking force to the reamer bar 40 and the reamer ring 50, the axial force is decomposed into radial components due to the conical fit between the connecting post 401 and the positioning hole 501. These radial components cause elastic deformation of the material of the connecting post 401 and / or the positioning hole 501, resulting in radial elastic contraction, thereby forming a tight interference fit between the conical surfaces. This interference fit not only provides a strong radial clamping force, effectively suppressing radial runout, but also increases the rigidity of the connection, ensuring the stability of the reamer during the cutting process.

[0076] In addition to the interference fit between the conical surfaces, the end face of the reamer ring 50 is also designed to fit tightly against the end face of the reamer rod 40. This design forms a "double-sided over-positioning" structure, which simultaneously utilizes the conical surfaces for precise radial and axial pre-positioning, and provides additional axial positioning and support through end-face contact. Conical surface positioning is mainly responsible for precise radial and partial axial alignment, while end-face contact further ensures the stability of the axial position and the ability to transmit axial forces. This dual positioning mechanism greatly improves the overall rigidity and stability of the connection, effectively resisting vibration and displacement caused by cutting forces. The combined design of the conical interference fit and double-sided over-positioning allows the reamer ring 50 to achieve extremely high repeatability each time it is installed on the reamer rod 40. A repeatability accuracy of ≤3μm means that after multiple disassemblies and installations, the radial and axial positional deviations of the reamer ring 50 relative to the reamer rod 40 are minimal, not exceeding 3μm.

[0077] This embodiment further proposes that it also includes a transmission pin 402 disposed between the reamer ring 50 and the reamer rod 40; the transmission pin 402 is used to transmit cutting torque.

[0078] A transmission pin 402 is a mechanical connector used to transmit torque. It is usually cylindrical or conical and is inserted into corresponding holes of two components that need to transmit torque, using the contact surface between the pin and the hole wall to transmit rotational force.

[0079] In the reamer structure, the drive pin 402 is designed to withstand shearing forces to ensure that the reamer ring 50 rotates stably with the reamer rod 40 during cutting, preventing relative slippage. The drive pin 402 is typically made of high-strength steel to withstand the enormous torque and impact generated during cutting. The drive pin 402 can be installed by an interference fit press-fit, or by a clearance fit supplemented with other fixing methods (such as screws) to prevent axial movement.

[0080] The placement of the drive pin 402 is crucial, as it needs to span the connection interface between the reamer ring 50 and the reamer shank 40. Specifically, one or more pin holes can be formed on the end face or side of the reamer shank 40, with corresponding matching pin holes formed on the reamer ring 50. When the reamer ring 50 is assembled with the reamer shank 40, the drive pin 402 is inserted into these aligned pin holes, thereby establishing a rigid torque transmission path between them. This arrangement ensures that the cutting torque can be directly transmitted from the reamer shank 40 to the reamer ring 50, avoiding the instability that may result from relying solely on friction to transmit torque. The primary function of the drive pin 402 is to provide a reliable mechanical connection to effectively and accurately transmit the rotational power from the machine tool spindle through the flange shank 10, adjustable flange 20, compensating tool holder 30, and reamer shank 40 to the reamer ring 50 and its indexable insert 60, enabling it to perform cutting operations. With the intervention of the transmission pin 402, the cutting torque no longer depends solely on the friction generated by the conical surface fit or end face contact, but is borne by the shear strength of the pin, which significantly improves the reliability and stability of torque transmission, especially under heavy-load cutting or intermittent cutting conditions.

[0081] This embodiment further proposes that it also includes a support guide 502 detachably disposed on the outer circumferential surface of the reamer ring 50; the support guide 502 is used to form an oil film support with the wall of the machined hole; the number of support guides 502 is 2 to 4, and they are evenly distributed along the outer circumference of the reamer ring 50; the outer diameter of the support guide 502 is 0.01mm to 0.03mm smaller than the outer diameter of the cutting edge of the reamer ring 50.

[0082] The support guide 502 is an auxiliary support element whose main function is to contact the wall of the hole being machined during reaming, providing radial support and stabilizing the cutting state of the reamer ring 50. Its detachable design means that the support guide 502 is not an integral part of the reamer ring 50, but is fixed to the outer circumference of the reamer ring 50 via reversible connections such as screws, clips, or dovetail grooves. This design facilitates replacement, adjustment, or removal according to different machining requirements, workpiece materials, or wear conditions, improving the versatility and maintenance convenience of the reamer. For example, the support guide 502 can be fixed in a pre-set mounting slot in the reamer ring 50 using screws, or a wedge structure can be used for quick clamping. The support guide 502 does not have rigid contact with the wall of the hole being machined; instead, a thin oil film is formed by cutting fluid or lubricant. This oil film effectively reduces the coefficient of friction between the support guide 502 and the hole wall, reducing wear, while providing hydraulic support to further stabilize the radial position of the reamer ring 50 and suppress vibration. The material used to support the guide bar 502 is typically selected from materials with good wear resistance and a low coefficient of friction, such as cemented carbide, ceramics, or steel with a specially treated surface (e.g., PVD / CVD coating). Its surface finish also needs to meet high requirements to facilitate the formation and stability of the oil film.

[0083] The number of support guides 502 is 2 to 4, evenly distributed along the outer circumference of the reamer ring 50. The range of 2 to 4 is based on engineering practice and mechanical balance considerations. For example, 3 support guides 502 provide more stable three-point support, effectively suppressing radial runout, and are a common choice for high-precision machining; 4 provide a more uniform support distribution, further improving stability. This even distribution ensures that the reamer ring 50 is subjected to uniform force in all radial directions, avoiding off-center loading and imbalance, thus guaranteeing the stability of the machining process and the roundness of the hole. The outer diameter of the support guides 502 is 0.01mm-0.03mm smaller than the outer diameter of the cutting edge of the reamer ring 50, a critical dimensional design. This dimensional relationship ensures that during cutting, the cutting edge contacts and cuts the workpiece first, and the support guides 502 contact the hole wall only after the cutting edge, avoiding scraping or squeezing of the hole wall by the support guides 502 before the cutting edge, which would affect the cutting effect. Meanwhile, the 0.01mm-0.03mm gap provides the necessary space for the cutting fluid or lubricant to form a stable oil film between the support guide 502 and the hole wall. This tiny gap ensures the formation of the oil film, provides sufficient hydraulic support, and limits the radial floating of the reamer ring 50.

[0084] This embodiment further proposes that the adjustable flange 20 is provided with a radial adjustment screw for adjusting the radial runout of the cutting edge.

[0085] Specifically, the radial adjusting screw is typically a precision threaded structure, with one end passing through the wall of the adjustable flange 20 and the other end abutting against the outer surface of the compensating tool holder 30 or reamer rod 40 connected to the adjustable flange 20. By screwing in or out this screw, a small radial thrust or pull can be generated on the adjustable flange 20 and its connected downstream components (such as the reamer rod 40 and reamer ring 50), thereby achieving radial position adjustment of the overall assembly. To achieve more stable and precise adjustment, at least two or more radial adjusting screws, such as three or four, are usually evenly distributed along the circumference on the adjustable flange 20 to form multi-point support and adjustment, ensuring the balance and controllability of the radial adjustment. After these screws are adjusted to the correct position, they are usually equipped with locking nuts or self-locking mechanisms to prevent loosening due to vibration during cutting, ensuring the stability of the adjusted position. Adjusting the radial runout of the cutting edge refers to fine-tuning the radial position of the cutting edge of the indexable insert 60 on the reamer ring 50 in the plane of rotation using the aforementioned radial adjustment screws. This ensures the position coincides as closely as possible with the theoretical rotation center of the reamer, thereby controlling the radial runout within the allowable tolerance range. In practice, after the reamer is mounted on the machine tool spindle, a high-precision measuring instrument (such as a dial indicator, micrometer, or non-contact laser measuring system) is used to measure the radial runout of the outer diameter of the cutting edge of the indexable insert 60 on the reamer ring 50. Based on the measurement results, the operator gradually adjusts the radial position of the adjustable flange 20 by individually or collectively screwing in / out the radial adjustment screws until the radial runout value of the cutting edge reaches or exceeds the preset accuracy requirements. This process aims to eliminate or compensate for radial deviations caused by manufacturing tolerances, assembly errors, and the runout of the machine tool spindle itself.

[0086] This embodiment further proposes that the overhang length of the compensating tool holder 30 is 3-6 times the diameter of the standard tool holder.

[0087] The overhang length of the compensating tool holder 30 refers to its effective working length from the clamping point to the connection point of the reamer ring 50. It is designed to be 3-6 times the diameter of a standard tool holder to significantly increase the effective extension of the tool, adapting to deep hole machining or special machining scenarios requiring a large extension. This design ensures bending and vibration resistance under long overhang by using high-strength, high-rigidity alloy steel or cemented carbide materials. For example, tool holders with optimized cross-sectional shapes (such as variable diameter or internal cavity structures) can be used to reduce weight while ensuring sufficient rigidity. Furthermore, the connection between the tool holder and the adjustable flange 20 can employ a high-precision fit to ensure connection rigidity and stability under long overhang conditions.

[0088] This embodiment further proposes that the surface of the indexable cutting tool 60 is provided with a wear-resistant coating.

[0089] The wear-resistant coating on the surface of the indexable insert 60 is a functional thin film formed on the insert substrate surface using techniques such as physical vapor deposition (PVD) or chemical vapor deposition (CVD). The main function of this coating is to improve the insert's hardness, wear resistance, oxidation resistance, and anti-adhesion properties, thereby extending the insert's service life. Common wear-resistant coating materials include titanium nitride (TiN), titanium carbonitride (TiCN), titanium aluminum carbonitride (TiAlN), and alumina (Al2O3). The choice of coating is usually optimized based on cutting conditions such as the type of material being machined, cutting speed, feed rate, and cooling method. For example, for machining steel, TiAlN coatings are often chosen due to their excellent heat resistance and oxidation resistance; for machining cast iron, TiCN coatings provide good wear resistance.

[0090] This embodiment further proposes that the expansion pin 80 is an eccentric structure. By rotating the expansion pin 80, the radial position of the reamer ring 50 relative to the reamer rod 40 can be adjusted, thereby achieving a fine adjustment of the diameter of the reamer ring 50. The fine adjustment range is ±0.02mm-±0.05mm.

[0091] Specifically, the adjusting pin 80 is designed with an eccentric structure, meaning that its central axis is offset from its own geometric axis. This eccentric design is key to achieving radial fine-tuning. Typically, the adjusting pin 80 has a cylindrical body, the center of which is not aligned with the axis of rotation. When the adjusting pin 80 rotates, its eccentric portion generates radial displacement, pushing or pulling the component it contacts. This radial displacement is cleverly used to change the radial position of the reamer ring 50 relative to the reamer rod 40. For example, the adjusting pin 80 can be inserted into a mating hole between the reamer ring 50 and the reamer rod 40, or connected to both via a lever mechanism. When the adjusting pin 80 rotates, its eccentricity causes a slight radial movement of the reamer ring 50, thereby changing the overall cutting diameter of the reamer ring 50. This adjustment is typically performed by inserting a special tool into the head of the adjusting pin 80 and can be precisely controlled according to a scale or indicator. The fine-tuning of the reamer ring 50 diameter refers to the precise adjustment of the reamer's cutting diameter within a very small range. This fine-tuning capability is crucial for meeting the stringent dimensional tolerances required for high-precision hole machining. Fine-tuning compensates for changes in insert wear, machining allowance, or dimensional variations between different batches of workpieces, ensuring that the machined hole diameter remains within tolerance. This fine-tuning range is ±0.02mm to ±0.05mm, meaning the diameter of the reamer ring 50 can be adjusted up or down by 0.02mm to 0.05mm from its nominal size. This range is sufficient to cover the minute dimensional corrections required for most high-precision reaming operations, providing exceptional flexibility and precision control.

[0092] This embodiment further proposes a reamer, which also includes an internal cooling channel disposed inside the reamer shank 40 and / or the compensating shank 30, the internal cooling channel being used to transport a cooling medium.

[0093] Specifically, the internal cooling channel can be a through hole formed inside the reamer shank 40 through a drilling process, or a pre-formed flow channel inside the compensating shank 30. Its main function is to directly deliver the cooling medium to the cutting area, thereby effectively reducing the cutting temperature, lubricating the cutting process, and facilitating the smooth removal of chips. The structure of this channel can be designed as a straight-through, spiral, or branched type according to actual needs, to adapt to different cooling strategies and structural constraints. The material of the channel is usually integrally formed with the body material of the reamer shank 40 or the compensating shank 30, or it can be achieved by embedding corrosion-resistant tubing to ensure stable delivery of the cooling medium and the durability of the channel.

[0094] The cooling medium can be a liquid medium such as water-based emulsion, synthetic cutting fluid, or cutting oil, or a gaseous medium such as compressed air or inert gas. The choice of cooling medium mainly depends on the characteristics of the material being machined, the specific machining process requirements, and environmental standards. Its core function is to efficiently remove the heat generated during the cutting process, reduce friction between the cutting tool and the workpiece, thereby effectively extending the service life of the indexable insert 60 and significantly improving the quality of the machined surface.

[0095] The cooling outlets of the internal cooling channel include a central internal cooling inlet and / or a distributed internal cooling inlet. The central internal cooling inlet is typically located at the center of the reamer's tip, designed to concentrate the cooling medium onto the bottom of the hole or the center of the cutting area, making it particularly suitable for deep hole machining or applications requiring strong chip flushing to prevent chip buildup. The distributed internal cooling inlets are typically located at the reamer's tip or near the indexable insert 60, evenly distributed along the circumference of the reamer ring 50. This design ensures that the cooling medium is evenly sprayed onto each cutting edge, guaranteeing adequate cooling and lubrication for each indexable insert 60, thereby comprehensively improving overall cutting performance and machining stability.

[0096] This embodiment also proposes a machine tool that includes the aforementioned reamer.

[0097] A machine tool is a device used for machining operations such as cutting, grinding, drilling, and boring. It provides power, motion, and control to enable the cutting tool to remove material from the workpiece according to a preset trajectory and parameters, thereby obtaining parts with the desired shape, size, and surface quality. A machine tool typically includes major components such as a bed, headstock, feed mechanism, control system, and cooling system. The headstock drives the tool rotation, the feed mechanism controls the relative movement of the tool or workpiece, and the control system coordinates the actions of each component to achieve complex machining processes. Common machine tool types include CNC machining centers, drilling machines, boring machines, and milling machines, all of which can serve as platforms for mounting reamers. Machine tools provide a stable mounting base, precise motion control, and the necessary cutting power for reamers, making them an indispensable component for achieving efficient and high-precision reaming.

[0098] This embodiment also proposes a method for using a reamer, which includes the following steps: selecting a reamer ring 50 of corresponding diameter and a compensating tool holder 30 of corresponding length according to the hole diameter and hole depth of the workpiece; installing an indexable insert 60 in the insert mounting groove of the reamer ring 50; the indexable insert 60 has two cutting edges, with the first cutting edge used initially; connecting the reamer ring 50 to the reamer rod 40 through a positioning structure, and locking it using a double-ended screw 70 and an adjusting expansion pin 80; and connecting the reamer rod 40 through the adjustable flange 2. Connect the compensating tool holder 30 to the flange main shank 10, and adjust the radial runout of the cutting edge to the preset requirement using the radial adjusting screw; install the support guide 502 on the reamer ring 50 according to the machining conditions; deliver coolant to the cutting area through the internal cooling channel; perform reaming, maintaining the preset hole tolerance and preset surface roughness during the machining process; when the first tool tip wears, rotate the indexable insert 60 180° to use the second tool tip; when both tool tips wear, replace the indexable insert 60 with a new one.

[0099] Specifically, in the process of using a reamer, the first step is to accurately select a reamer ring 50 of appropriate diameter and a compensating shank 30 of suitable length based on the hole diameter and depth requirements of the part to be machined. This step is fundamental to ensuring that the reamer matches the machining task, demonstrating the advantages of the reamer's modular design, and enabling the same reamer system to adapt to the machining needs of holes of different specifications.

[0100] Subsequently, the indexable insert 60 is installed into the pre-set insert mounting slot of the reamer ring 50. The indexable insert 60 is designed with two usable cutting tips, which significantly improves tool utilization and economy. During initial installation, one of the cutting tips (e.g., the first cutting tip) is typically selected for cutting operations. The insert installation must ensure that it is secure and accurately positioned to guarantee the stability of the cutting process and machining accuracy.

[0101] Next, the reamer ring 50 is connected to the reamer rod 40 via a positioning structure. This positioning structure, for example, the fit between the connecting post 401 of the reamer rod 40 and the positioning hole 501 of the reamer ring 50, ensures precise alignment between the reamer ring 50 and the reamer rod 40. After connection, an axial tension force is provided using a double-ended screw 70, while radial locking and fine-tuning are performed using an adjusting expansion pin 80. For example, when the connecting post 401 is a 10° hollow short cone and the positioning hole 501 is a 10° inner short cone hole, under the action of the locking force, the reamer rod 40 and the reamer ring 50 will undergo radial elastic contraction, causing the conical surface of the connecting post 401 to form an interference fit with the conical hole of the positioning hole 501, while the end face of the reamer ring 50 fits against the end face of the reamer rod 40, forming a double-sided over-positioning of conical surface positioning and end face contact, thereby achieving a repeatability accuracy ≤3μm. In addition, a transmission pin 402 can be provided between the reamer ring 50 and the reamer rod 40 to effectively transmit the cutting torque.

[0102] After the reamer ring 50 is connected and locked to the reamer rod 40, the reamer rod 40 is connected to the compensating tool holder 30 via the adjustable flange 20. The adjustable flange 20 plays a key role in this step, allowing for fine adjustment of the radial position of the reamer rod 40. The compensating tool holder 30 provides the necessary overhang length to accommodate different hole depths and machining space requirements.

[0103] Subsequently, the compensating tool holder 30 is connected to the flange main shank 10, which is then ultimately connected to the machine tool spindle. After the overall assembly is completed, the radial runout of the cutting edge is precisely adjusted using the radial adjusting screws on the adjustable flange 20 to achieve the preset accuracy requirements. This adjustment step is crucial for eliminating assembly errors, tool manufacturing errors, and ensuring the roundness and coaxiality of the final machined hole. For example, the adjusting expansion pin 80 can be designed as an eccentric structure. By rotating this adjusting expansion pin 80, the radial position of the reamer ring 50 relative to the reamer rod 40 can be adjusted, achieving fine adjustment of the diameter of the reamer ring 50. The fine adjustment range can reach ±0.02mm-±0.05mm.

[0104] Depending on the specific machining conditions and the required machining quality, support guides 502 can be detachably installed on the outer circumference of the reamer ring 50. During machining, the support guides 502 form an oil film with the wall of the machined hole, which helps improve machining stability, reduce vibration, and improve the surface quality of the hole. Typically, there are 2 to 4 support guides 502, evenly distributed along the outer circumference of the reamer ring 50, with an outer diameter slightly smaller than the outer diameter of the cutting edge of the reamer ring 50, for example, 0.01mm-0.03mm smaller.

[0105] To effectively control cutting temperature, lubricate the cutting process, and promptly remove chips, coolant is supplied to the cutting area through internal cooling channels located inside the reamer 40 and / or the compensating shank 30. The outlet of the internal cooling channel may include a central internal cooling port and / or a distributed internal cooling port, ensuring that the cooling medium can directly act on the cutting edge.

[0106] After completing all the above preparations and adjustments, the reaming process can be performed. During the machining process, all parameters must be strictly controlled to maintain the preset hole tolerances and surface roughness, ensuring that the machining quality meets the requirements.

[0107] To maximize tool life, when the first tip of the indexable insert 60 wears, it is not necessary to immediately replace the entire insert. Simply rotate the indexable insert 60 180° to use its second, unworn tip for continued machining. Only when both tips are worn beyond repair should the indexable insert 60 be replaced with a new one.

[0108] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A reamer, characterized in that, include: Flange main handle (10) is used to connect to the machine tool spindle; The compensating tool holder (30) is connected to the flange main handle (10) and the adjustable flange (20) respectively, and is used to move the position of the adjustable flange (20) forward in the direction of the cutting edge to shorten the distance from the cutting edge of the reamer ring (50) to the positioning surface of the adjustable flange (20); The reamer bar (40) is connected to the compensating shank (30) via the adjustable flange (20); The reamer ring (50) is connected to the reamer rod (40) through a positioning structure; the reamer ring (50) is provided with multiple blade mounting slots; Indexable inserts (60) are installed in the insert mounting slot of the reamer ring (50); each indexable insert (60) has two indexable cutting tips; The locking assembly includes a double-ended screw (70) and an adjusting expansion pin (80) for tightening the reamer ring (50) to the reamer rod (40).

2. The reamer according to claim 1, characterized in that, The positioning structure includes a connecting post (401) of the reamer rod (40) and a positioning hole (501) in which the reamer ring (50) cooperates with the connecting post (401).

3. The reamer according to claim 2, characterized in that, The connecting post (401) is a 10° hollow short cone, and the positioning hole (501) is a 10° inner short cone hole. After the reamer rod (40) and the reamer ring (50) are locked, they generate radial elastic contraction under the action of locking force, so that the conical surface of the connecting post (401) and the conical hole of the positioning hole (501) form an interference fit. The end face of the reamer ring (50) is in contact with the end face of the reamer rod (40), forming a double-sided over-positioning with conical surface positioning and end face contact, and the repeatability positioning accuracy is ≤3μm.

4. The reamer according to claim 1, characterized in that, It also includes a drive pin (402) disposed between the reamer ring (50) and the reamer rod (40); the drive pin (402) is used to transmit cutting torque.

5. The reamer according to claim 1, characterized in that, It also includes a support guide (502) detachably disposed on the outer circumferential surface of the reamer ring (50); the support guide (502) is used to form an oil film support with the wall of the machined hole; the number of the support guide (502) is 2 to 4, and they are evenly distributed along the outer circumference of the reamer ring (50); the outer diameter of the support guide (502) is 0.01mm to 0.03mm smaller than the outer diameter of the cutting edge of the reamer ring (50).

6. The reamer according to claim 1, characterized in that, The adjustable flange (20) is provided with a radial adjustment screw for adjusting the radial runout of the cutting edge.

7. The reamer according to claim 1, characterized in that, The adjusting pin (80) is an eccentric structure. By rotating the adjusting pin (80), the radial position of the reamer ring (50) relative to the reamer rod (40) can be adjusted, thereby achieving fine adjustment of the diameter of the reamer ring (50). The fine adjustment range is ±0.02mm-±0.05mm.

8. The reamer according to claim 1, characterized in that, It also includes an internal cooling channel disposed inside the reamer bar (40) and / or the compensating shank (30); the internal cooling channel is used to transport cooling medium; the outlet of the internal cooling channel includes a central internal cooling port and / or a dispersed internal cooling port.

9. A machine tool, characterized in that, Includes the reamer as described in any one of claims 1-8.

10. A method of use, characterized in that, The process, performed using a reamer as described in any one of claims 1-8, includes the following steps: Select a reamer ring (50) of the corresponding diameter and a compensating tool holder (30) of the corresponding length according to the hole diameter and hole depth of the workpiece. The indexable insert (60) is installed in the insert mounting slot of the reamer ring (50); the indexable insert (60) has two cutting tips, with the first cutting tip being used first. The reamer ring (50) is connected to the reamer rod (40) by a positioning structure and locked using a double-ended screw (70) and an adjusting expansion pin (80); The reamer bar (40) is connected to the compensating tool holder (30) via the adjustable flange (20); Connect the compensation tool holder (30) to the flange main handle (10) and use the radial adjustment screw to adjust the radial runout of the cutting edge to the preset requirement; According to the processing conditions, a support guide (502) is installed on the reamer ring (50); Coolant is delivered to the cutting area through an internal cooling channel; Perform reaming machining, maintaining the preset hole tolerance and preset surface roughness during the machining process; When the first cutting tip wears out, the indexable insert (60) is rotated 180° to use the second cutting tip; when both cutting tips wear out, a new indexable insert (60) is replaced.

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