Honing head high cylindricity on-machine finishing method

Abstract

The invention discloses a honing head high cylindricity on-machine finishing method which comprises the following steps: S1, disassembling an original workpiece, and assembling a honing finisher of which the surface of an inner hole is plated with an abrasive particle layer to the position of the original workpiece in situ; s2, the oilstone is driven to expand in the radial direction until effective contact is established between the oilstone and an inner hole abrasive particle layer of the honing dresser; s3, the honing head is driven to do composite motion of axial reciprocating motion and rotary motion in the honing dresser according to preset dressing parameters, and the outer circle contour formed by combining the oilstones is dressed through the interaction of the oilstones and the inner hole abrasive particle layer of the honing dresser; s4, after the finishing period is finished, the finishing effect of the honing head is verified until the cylindricity of the outer circle contour formed by the oilstone combination reaches the standard; and S5, after the cylindricity is confirmed to meet the precision requirement, finishing the finishing process. According to the method, in-place precise finishing of the honing head is achieved, positioning errors caused by repeated disassembly and assembly are eliminated, it is ensured that the finished honing head is high in cylindricity, and the strict requirement of a high-precision machining scene for a honing tool is met.

Description

Technical Field

[0001] This invention relates to the field of precision machining technology, and in particular to an in-machine dressing method for high cylindricity of honing heads. Background Technology

[0002] Servo valve sleeves, hydraulic actuators, and other high-aspect-ratio bore parts are widely used in high-end equipment fields such as aerospace and precision instruments. The dimensional accuracy and cylindricity of their inner holes directly affect the fitting accuracy of assembled components, reducing equipment performance, reliability, and service life. In internal honing, an oilstone mounted on the honing head moves radially along the honing head, applying cutting pressure to the workpiece's inner hole. The surface of the part is ground through the rotational and reciprocating motion of the honing head relative to the workpiece. Due to its unique floating connection mechanism and radial force self-balancing characteristics based on surface contact, honing has become a key process for achieving high dimensional accuracy and high cylindricity in the manufacturing of high-aspect-ratio bore parts such as servo valve sleeves and hydraulic actuators.

[0003] Honing essentially determines the final geometric accuracy and surface quality of the workpiece's inner hole through the outer cylindrical profile formed by the combination of honing stones. Therefore, a prerequisite for ensuring the quality of inner hole machining is that the outer cylindrical profile formed by the honing stone combination must possess high cylindricity, and the honing stones must maintain stable high cutting performance. However, in practical engineering applications, manufacturing errors and cumulative assembly errors of the honing head and honing stones are difficult to avoid. Furthermore, uneven wear of the honing stones during use further affects the accuracy of the outer cylindrical profile and the cutting performance of the honing stones. Therefore, regular precision dressing of the honing head is a key technical step to compensate for accumulated manufacturing and assembly errors, reconstruct the high cylindricity of the honing head, and maintain the high-performance cutting capabilities of the honing stones.

[0004] Currently, honing head dressing mainly includes two methods: in-situ dressing and offline dressing. In-situ dressing relies on skilled operators using handheld grinding wheels or small, simple dressing devices to dress the honing stone on the honing head based on their experience. This method is only suitable for trimming sharp edges of the honing stone during honing or sharpening a clogged honing stone, and it's difficult to guarantee the cylindricity and other shape accuracy of the honing head. Furthermore, it requires a high level of operator skill. Offline dressing, on the other hand, uses specialized tooling and fixtures to dress the honing stone or honing head through grinding. To address the problem of existing honing stone cylindricity dressing methods where the push rod is not fixed, causing the honing stone to lose its stable radial position during dressing and thus preventing proper dressing, patent CN103182682A discloses a "method for rounding a honing strip using a honing head." This method uses a push rod limiting pad to restrict the axial movement of the expansion mandrel and employs a cylindrical grinding machine with double centers to hold the center holes at both ends of the honing head for dressing the honing stone. Clearly, this method relies on the high-precision center holes on the expansion mandrel and honing head body for clamping and positioning. However, most actual honing heads do not have a double-center center hole structure. Furthermore, the center holes are easily contaminated or worn during honing head use, making it difficult to meet the high-precision dressing and clamping requirements of the honing head. Therefore, this method is only applicable to the dressing of specific honing heads. Furthermore, although this method does not require the preparation of special dressing fixtures, the installation and removal of the top rod limit pads during the dressing process must first remove the oilstone and push rod before the adjustment operation can be carried out, which will introduce assembly errors before and after the oilstone dressing, and the operation process is complicated, time-consuming and labor-intensive.

[0005] Traditional in-situ honing relies heavily on skilled operators' experience, which easily introduces human error and results in poor accuracy. Traditional offline honing involves disassembling and reassembling the honing head, which accumulates installation errors and is inefficient. Chinese Patent CN117921528A discloses a honing stone straightening device and method. This method involves placing the honing head with the honing stone into a specially designed fixture, using a high-precision straightener within the fixture to improve the straightness and surface unevenness of the honing stone. While this avoids human error and offline disassembly / installation errors and achieves high straightness of the honing stone, the correction amount is minimal, and the involved fixtures and equipment are complex, costly, and cumbersome, making it difficult to meet the demands of high-efficiency production.

[0006] In summary, there is an urgent need to develop a dressing method that can achieve high precision and improve the cylindricity of honing heads in machine dressing, so as to effectively improve the cylindricity of honing heads and the cutting performance of honing stones, and meet the high-precision honing requirements of hole-type parts in aerospace, precision instruments and other fields. Summary of the Invention

[0007] The purpose of this invention is to provide an in-machine dressing method for honing heads with high cylindricity, so as to solve the problems existing in the prior art.

[0008] To achieve the above objectives, the present invention provides the following solution: The present invention provides an in-machine dressing method for high cylindricity of honing heads, comprising the following steps: S1, disassemble the original workpiece, and assemble the honing dresser with the abrasive coating on the inner hole surface into the original workpiece position, ensuring that the honing dresser is coaxial with the machine tool spindle and fixed. S2, based on the characteristics of the honing head and honing stone, preset the radial feed pressure, place the honing head to be dressed in the inner hole of the honing dresser, and use the floating connection mechanism of the honing machine spindle or workpiece to eliminate the coaxiality deviation between the honing head and the honing dresser; drive the honing stone to expand radially until it establishes effective contact with the abrasive layer in the inner hole of the honing dresser; S3, according to the preset dressing parameters, drives the honing head to perform a composite motion of axial reciprocating motion and rotational motion in the honing dresser; S4. After the dressing cycle is completed, the dressing effect of the honing head is verified. If the verification index does not meet the preset accuracy requirements, the parameters are iteratively adjusted according to the test results and the S2-S3 steps are repeated until the cylindricity of the outer circle contour formed by the oilstone combination meets the standard. S5. After confirming that the cylindricity of the honing head meets the accuracy requirements, the dressing process is completed.

[0009] According to the in-situ cylindricity honing head dressing method provided by the present invention, in step S1, the in-situ assembly of the honing dresser includes the following steps: S1-1, Remove the original workpiece from the machine tool spindle or workpiece floating fixture, while keeping the installation position and state of the workpiece floating fixture on the machine tool unchanged; S1-2, precisely install the honing dresser to the original workpiece's mounting position, ensuring that the honing dresser axis is coaxially aligned with the machine tool spindle; S1-3 The honing dresser is installed through a precision clamping system. The honing head is connected to the spindle in a floating or rigid manner with a floating clamp to reduce the influence of the coaxiality error between the spindle rotation center and the honing dresser.

[0010] According to the in-machine dressing method for high cylindricity honing head provided by the present invention, in S1, the honing dresser is rigidly locked by a precision clamping system based on the original workpiece's mounting interface and clamping method, so as to inherit the original workpiece's positioning reference and ensure the positional stability of the honing dresser during the dressing process.

[0011] In the on-machine dressing method for high cylindricity of honing head provided by the present invention, in S1, the working surface of the honing head includes a honing stone as the main cutting element and a diamond or cemented carbide guide strip as an auxiliary guiding element that undertakes the task of guiding and supporting.

[0012] In the on-machine dressing method for high cylindricity of honing heads provided by the present invention, in S2, the basis for preset radial feed pressure includes the effective contact area of ​​the honing stone, the characteristics of the honing stone, the spindle rotation speed, and the axial reciprocating speed of the honing head to be dressed.

[0013] According to the in-machine dressing method for high cylindricity honing heads provided by the present invention, in S2, a radial expansion pressure is preset based on the honing stone grit size, hardness, and effective contact area of ​​the honing head; the progressive expansion of the honing stone is controlled by hydraulic drive or servo motor drive; during this process, a honing dresser with an inner hole coated with an abrasive layer is used as a fixed reference, and the honing head, as the active object, performs a spiral composite motion of circumferential rotation and axial reciprocating within the inner hole of the honing dresser, thereby realizing the reverse dressing of the honing head by the honing dresser.

[0014] In the honing head high cylindricity in-machine dressing method provided by the present invention, in S3, the preset honing dressing parameters include radial feed pressure, axial reciprocating motion speed, spindle rotation speed, and dressing cycle.

[0015] In the on-machine dressing method for high cylindricity of honing heads provided by the present invention, the reason why the honing dresser can efficiently dress the oilstone in S3 is fundamentally due to the significant difference in abrasive particle size and bond strength between the two. The abrasive particle size of the inner wall of the honing dresser is set to be larger than that of the oilstone abrasive particles, and its bond strength is set to be higher than that of the oilstone bond strength, ensuring that its own abrasive particles are stably fixed. Under the action of feed pressure and compound motion, it establishes effective contact with the abrasive layer inside the honing dresser, causing the oilstone abrasive particles to undergo micro-fracture or fall off, thereby causing the outer circular contour formed by the oilstone combination to gradually converge and approach the high-precision geometry of the dressing reference surface, thus ensuring the high cylindricity of the honing head and the high-performance cutting of the oilstone after dressing.

[0016] In the in-machine dressing method for high cylindricity of honing heads provided by the present invention, in S4, the method for verifying the dressing effect of the honing head is selected from one or a combination of the following: Method 1: Online measurement verification, using a non-contact laser measuring instrument or contact probe equipped on the machine tool to directly measure the cylindricity error of the honing head's oilstone working surface after dressing; Method 2: Trial processing verification, removing the honing dresser, clamping a standard test piece for trial processing, and indirectly determining the dressing accuracy of the honing head by measuring the cylindricity of the inner hole of the test piece.

[0017] In the honing head high cylindricity in-machine dressing method provided by the present invention, in S3 and S4, the dressing cycle can be set to one of the following two modes: dressing duration based on time; dressing stroke length based on distance.

[0018] The present invention discloses the following technical effects: This invention proposes an in-machine dressing method for achieving high cylindricity of honing heads. Compared with existing online and offline dressing methods, this method achieves in-situ dressing of the honing head. The workpiece is disassembled, and the honing dresser is installed in situ at the workpiece location, eliminating the need to disassemble the honing head. This significantly shortens dressing time and fundamentally eliminates assembly errors introduced by repeated disassembly and reassembly of the honing head. During the dressing process, this method can simultaneously adjust the cylindricity of the outer contour formed by the honing stone assembly and the cutting performance of the honing stone itself. This method effectively reduces the dressing cycle, improves dressing accuracy, and exhibits excellent stability during the dressing process, making it suitable for mass industrial high-precision honing dressing applications.

[0019] This invention proposes an in-machine dressing method for honing heads with high cylindricity. Compared with existing dressing methods, this method proposes to use a tool with high inner hole cylindricity, similar in size to the inner hole of the part to be honed and with superhard abrasive grains prepared in the inner hole, as the honing head oilstone dresser to perform in-situ dressing of the honing head. The dressing method of this invention only requires treating the dresser as a part in operation, installing it according to the operating procedures of the part to be honed, and then starting the honing program to complete the high-precision dressing of the honing oilstone. No modification to existing equipment or tools is required. It offers high dressing accuracy, is convenient and quick to use, effectively improves operating efficiency, reduces alignment errors, and eliminates the requirement that dressing accuracy heavily depends on operators or other high-precision equipment. It easily enables automated and industrialized precision dressing of honing heads. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram illustrating the dressing principle of the honing head of the present invention; Figure 2 This is a schematic diagram of the in-machine dressing method for high cylindricity of the honing head according to the present invention; Figure 3 This is a flowchart of the in-machine dressing method for achieving high cylindricity of the honing head according to the present invention.

[0022] Among them, 1. Grinding head body; 2. Oilstone; 3. Guide bar; 4. Push rod; 5. Honing dresser; 6. Coupling; 51. Abrasive layer; 52. Consolidation layer; 53. Sleeve. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] Reference Figure 1-3 This invention provides an in-machine dressing method for achieving high cylindricity of a honing head, comprising the following steps: S1, disassemble the original workpiece, and assemble the honing dresser with the abrasive coating on the inner hole surface into the original workpiece position, ensuring that the honing dresser is coaxial with the machine tool spindle and fixed. S2, based on the characteristics of the honing head and honing stone, preset the radial feed pressure, place the honing head to be dressed in the inner hole of the honing dresser, and use the floating connection mechanism of the honing machine spindle or workpiece to eliminate the coaxiality deviation between the honing head and the honing dresser; drive the honing stone to expand radially until it establishes effective contact with the abrasive layer in the inner hole of the honing dresser; S3, according to the preset dressing parameters, drives the honing head to perform a composite motion of axial reciprocating motion and rotational motion in the honing dresser, and improves the cylindricity of the outer circle profile formed by the oilstone combination through the reverse dressing mechanism. S4. After the dressing cycle is completed, the dressing effect of the honing head is verified. If the verification index does not meet the preset accuracy requirements, the parameters are iteratively adjusted according to the test results and the S2-S3 steps are repeated until the cylindricity of the outer circle contour formed by the oilstone combination meets the standard. S5. After confirming that the cylindricity of the honing head meets the accuracy requirements, the dressing process is completed.

[0026] Further optimization of the scheme: In S1, the in-situ assembly of the honing dresser includes the following steps: S1-1, Remove the original workpiece from the machine tool spindle or workpiece floating fixture, while keeping the installation position and state of the workpiece floating fixture on the machine tool unchanged; S1-2, precisely install the honing dresser to the original workpiece's mounting position, ensuring that the honing dresser axis is coaxially aligned with the machine tool spindle; S1-3 The honing dresser is installed through a precision clamping system. The honing head is connected to the spindle in a floating or rigid manner with a floating clamp to reduce the influence of the coaxiality error between the spindle rotation center and the honing dresser.

[0027] Further optimizing the scheme, in S1, the honing dresser is installed using a precision clamping system based on the original workpiece's installation interface and clamping method. This system rigidly locks the honing dresser to inherit the original workpiece's positioning reference and ensure the positional stability of the honing dresser during the dressing process.

[0028] In a further optimized design, in S1, the working surface of the honing head includes an oilstone as the main cutting element and a diamond or carbide guide strip as an auxiliary guiding element that undertakes the task of guiding and supporting.

[0029] Further optimization of the scheme: In S2, the preset radial feed pressure is based on the effective contact area of ​​the honing stone, the characteristics of the honing stone, the spindle rotation speed, and the axial reciprocating speed of the honing head to be dressed.

[0030] Further optimization of the scheme: In S2, the radial expansion pressure is preset according to the grit size, hardness, and effective contact area of ​​the honing head; the progressive expansion of the honing stone is controlled by hydraulic drive or servo motor drive; during this process, the honing dresser with an inner hole coated with an abrasive layer is used as a fixed reference, and the honing head, as the active object, performs a spiral composite motion of circumferential rotation and axial reciprocating within the inner hole of the honing dresser, realizing the reverse dressing of the honing head by the honing dresser, so that the outer circle contour formed by the honing stone combination approaches the high-precision geometry of the dressing reference surface.

[0031] Further optimization of the scheme: In S3, the preset honing and dressing parameters include radial feed pressure, axial reciprocating speed, spindle rotation speed, and dressing cycle.

[0032] Further optimization of the scheme reveals that the honing dresser in S3 can efficiently dress the oilstone primarily due to the significant difference in abrasive particle size and bond strength between the two. The abrasive particle size on the inner wall of the honing dresser is set to be larger than that of the oilstone abrasive particles, and its bond strength is set to be higher than that of the oilstone bond strength. This ensures the stable fixation of its own abrasive particles. Under the action of feed pressure and compound motion, it establishes effective contact with the abrasive layer inside the honing dresser, causing the oilstone abrasive particles to undergo micro-fragmentation or detachment. Consequently, the outer circular contour formed by the oilstone combination gradually converges and approaches the high-precision geometry of the dressing reference surface, thus ensuring the high cylindricity of the honing head and the high-performance cutting of the oilstone after dressing.

[0033] To further optimize the scheme, in S4, the method for verifying the dressing effect of the honing head is selected from one or a combination of the following: Method 1: Online measurement verification, using a non-contact laser measuring instrument or contact probe equipped on the machine tool to directly measure the cylindricity error of the honing head's oilstone working surface after dressing; Method 2: Trial processing verification, removing the honing dresser, clamping a standard test piece for trial processing, and indirectly determining the dressing accuracy of the honing head by measuring the cylindricity of the test piece's inner hole.

[0034] To further optimize the scheme, in S3 and S4, the trimming cycle can be set to one of the following two modes: trimming duration based on time; trimming travel length based on distance.

[0035] The present invention relates to an in-machine method for high cylindricity honing head dressing, which is based on a honing head, a honing dresser, a transmission system, a feed system, a reciprocating motion system, and a floating connection mechanism. The core of the method is to use the honing dresser as a fixed reference and utilize the existing machine tool system to drive the honing head to perform a composite motion of axial reciprocating motion and rotational motion, thereby achieving in-machine reverse dressing of the cylindricity of the honing head.

[0036] The honing head consists of a honing head body 1, a push rod 4, a honing stone 2, and a guide bar 3, which form the main rigid frame. The push rod 4 is driven by a mechanical or hydraulic system to generate axial displacement, which is converted into radial extension and retraction motion of the honing stone 2 through the internal conical or inclined surface mechanism of the honing head. The guide bar 3, which is asymmetrically arranged on the circumference of the honing head body 1, provides guidance and support for the honing head.

[0037] The honing dresser has a precision cylindrical structure, consisting of an abrasive layer 51, a bonding layer 52, and a sleeve 53. The abrasive layer 51 uses superhard abrasive grains such as diamond, which can be manufactured through electroplating / sintering / brazing processes. It is uniformly distributed and has high bonding strength, exhibiting excellent wear resistance and cutting performance. The bonding layer 52 uses brazing or bonding processes to firmly bond the abrasive layer 51 to the sleeve 53. The sleeve 53 is made of high-strength alloy, and its outer diameter is precisely matched with the floating fixture of the honing machine workpiece, facilitating quick in-situ installation.

[0038] The reason why honing dressers can efficiently dress oilstones lies in the significant difference in abrasive grain size and bond strength between the two. The abrasive grain size on the inner wall of the honing dresser is set to be larger than that of the oilstone abrasive grains, and its bond strength is set to be higher than that of the oilstone bond strength. This ensures that its own abrasive grains are stably fixed. Under the action of feed pressure and compound motion, they establish effective contact with the abrasive grain layer inside the honing dresser, causing the oilstone abrasive grains to undergo micro-fragmentation or detachment. As a result, the outer circular contour formed by the oilstone combination gradually converges and approaches the high-precision geometry of the dressing reference surface, thus ensuring the high cylindricity of the honing head and the high-performance cutting of the oilstone after dressing.

[0039] The transmission system includes a spindle servo motor and a coupling. The power output of the spindle servo motor is transmitted to the honing spindle without backlash through the coupling, driving the honing spindle to perform precise and constant-speed rotational motion.

[0040] The reciprocating motion system includes a reciprocating servo motor, a ball screw, and a screw nut. The reciprocating servo motor controls and drives the ball screw, which in turn drives the screw nut to perform precise linear motion. The honing spindle is rigidly connected to the screw nut to achieve uniform and stable axial reciprocating motion, ensuring commutation accuracy, stability, and consistency over long strokes.

[0041] The feed system uses a mechanical or hydraulic system as a power source to drive the push rod to move axially. This movement is then converted into radial extension and retraction motion of the honing stone through the conical or inclined surface mechanism inside the honing head, achieving precise micro-feeding and controlling the radial pressure of the honing stone relative to the dressing reference surface.

[0042] Example: S1, honing dresser assembled in situ; Stop the honing machine, release the workpiece floating fixture, remove the original workpiece to be processed, and at the same time keep the installation position and state of the workpiece floating fixture on the machine tool unchanged, and ensure that the honing head is in a fully retracted state to avoid interference during assembly; accurately install the honing dresser that has been fully prepared and passed quality inspection to the original workpiece installation position. Among them, the abrasive layer 51 on the inner wall of the honing dresser is evenly distributed and has a qualified bonding strength, and the inner hole has high cylindricity. The honing dresser is fixed by a precision clamping system, and the floating connection mechanism of the honing machine spindle or workpiece is used to compensate for the coaxiality error between the spindle rotation center and the honing dresser. S2, radial expansion bonding of oilstone; The preset radial feed pressure is set based on the material properties, diameter, length, and honing stone characteristics of the honing head to be dressed. In this example, the material properties of the honing head to be dressed are structural steel S355, with a yield strength of 400MPa, a diameter of 7.9mm, and a length of 290mm. The honing stone uses 180-mesh diamond abrasive. Based on the above parameters, the radial feed pressure is determined to be 1.2kPa.

[0043] Place the honing head to be dressed in the inner hole of the honing dresser, start the machine tool's hydraulic or mechanical drive system, and drive the honing stone of the honing head to gradually expand outward in the radial direction, using the honing dresser with the inner hole coated with abrasive grains as a fixed reference, until the working surface of the honing stone and the dressing reference surface establish effective contact.

[0044] S3, compound motion reverse adjustment; The preset dressing parameters include radial feed pressure and axial reciprocating speed. In this example, the stroke speed is 50 strokes / min, the rotation speed is 800 r / min, the dressing cycle is 2 min, and the overtravel is set to L / 3, where L is the length of the oilstone.

[0045] The honing head is driven to perform controlled axial reciprocating and rotary motions within the honing dresser. Under a preset constant or variable radial pressure, the honing stone establishes effective contact with the abrasive layer within the honing dresser, causing the abrasive grains of the honing stone to undergo micro-fracture or detachment. This makes the outer circular profile formed by the combination of honing stones approach the high-precision geometry of the dressing reference surface, thereby ensuring the high cylindricity of the honing head and the high-performance cutting of the honing stone after dressing. S4, Iterative detection and parameter adjustment; After the preset dressing cycle is completed, the honing head drive is stopped. In this example, method two is selected: trial processing verification. The honing dresser is removed, and a standard specimen is clamped for trial processing. In this example, a cylindricity meter is used to measure the cylindricity of the inner hole of the specimen to indirectly determine the dressing accuracy of the honing head.

[0046] If the shape tolerance requirements are not met after parameter fine-tuning and iteration, the trimming parameters are fine-tuned based on the detection data, including axial reciprocating motion speed, radial feed pressure, rotation speed, trimming cycle, etc., and the process is returned to steps S2-S3 to continue trimming. The iteration process is controlled within 1-3 times to avoid excessive material removal that could lead to dimensional deviations.

[0047] S5, complete the repair; After confirming that the cylindricity of the honing head has reached the preset accuracy requirements, stop the machine tool, release the precision clamping system, remove the honing head, and complete the entire in-machine dressing process.

[0048] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0049] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for on-machine dressing of a honing head to achieve high cylindricity, characterized in that, Includes the following steps: S1, disassemble the original workpiece, and assemble the honing dresser with the abrasive coating on the inner hole surface into the original workpiece position, ensuring that the honing dresser is coaxial with the machine tool spindle and fixed. S2, based on the characteristics of the honing head and honing stone, preset the radial feed pressure, place the honing head to be dressed in the inner hole of the honing dresser, and use the floating connection mechanism of the honing machine spindle or workpiece to eliminate the coaxiality deviation between the honing head and the honing dresser; drive the honing stone to expand radially until it establishes effective contact with the abrasive layer in the inner hole of the honing dresser; S3, according to the preset dressing parameters, drives the honing head to perform a composite motion of axial reciprocating motion and rotational motion in the honing dresser; S4. After the dressing cycle is completed, the dressing effect of the honing head is verified. If the verification index does not meet the preset accuracy requirements, the parameters are iteratively adjusted according to the test results and the S2-S3 steps are repeated until the cylindricity of the outer circle contour formed by the oilstone combination meets the standard. S5. After confirming that the cylindricity of the honing head meets the accuracy requirements, the dressing process is completed.

2. The method for on-machine dressing of a honing head with high cylindricity according to claim 1, characterized in that, In S1, the in-situ assembly of the honing dresser includes the following steps: S1-1, Remove the original workpiece from the machine tool spindle or workpiece floating fixture, while keeping the installation position and state of the workpiece floating fixture on the machine tool unchanged; S1-2, precisely install the honing dresser to the original workpiece's mounting position, ensuring that the honing dresser axis is coaxially aligned with the machine tool spindle; S1-3 The honing dresser is installed through a precision clamping system. The honing head is connected to the spindle in a floating or rigid manner with a floating clamp to reduce the influence of the coaxiality error between the spindle rotation center and the honing dresser.

3. The method for on-machine dressing of a honing head with high cylindricity according to claim 1, characterized in that, In S1, the honing dresser is installed according to the original workpiece's installation interface and clamping method. A precision clamping system is used to rigidly lock the honing dresser to inherit the original workpiece's positioning reference and ensure the positional stability of the honing dresser during the dressing process.

4. The method for on-machine dressing of a honing head with high cylindricity according to claim 1, characterized in that, In S2, the preset radial feed pressure is based on the effective contact area of ​​the honing stone, the characteristics of the honing stone, the spindle rotation speed, and the axial reciprocating speed of the honing head to be dressed.

5. The method for on-machine dressing of a honing head with high cylindricity according to claim 1, characterized in that, In S2, the radial expansion pressure is preset according to the grit size, hardness, and effective contact area of ​​the honing head. The progressive expansion of the honing stone is controlled by hydraulic drive or servo motor drive. During this process, the honing dresser with an inner hole coated with an abrasive layer is used as a fixed reference. The honing head, as the active object, performs a spiral composite motion of circumferential rotation and axial reciprocating within the inner hole of the honing dresser. This achieves the reverse dressing of the honing head by the honing dresser, making the outer circle profile formed by the honing stone combination approach the high-precision geometric shape of the dressing reference surface.

6. The method for on-machine dressing of a honing head with high cylindricity according to claim 1, characterized in that, In S3, the preset honing and dressing parameters include radial feed pressure, axial reciprocating speed, spindle rotation speed, and dressing cycle.

7. The method for on-machine dressing of a honing head with high cylindricity according to claim 1, characterized in that, In S3, the abrasive grain size of the inner wall of the honing dresser is set to be larger than that of the oilstone abrasive grain, and its binder strength is set to be higher than that of the oilstone binder, so that the oilstone abrasive grain will be micro-broken or fall off during the dressing process.

8. The method for on-machine dressing of a honing head with high cylindricity according to claim 1, characterized in that, In S4, the method for verifying the dressing effect of the honing head is selected from one or a combination of the following: Method 1: Online measurement verification, using a non-contact laser measuring instrument or contact probe equipped on the machine tool to directly measure the cylindricity error of the honing head's oilstone working surface after dressing; Method 2: Trial processing verification, removing the honing dresser, clamping a standard test piece for trial processing, and indirectly determining the dressing accuracy of the honing head by measuring the cylindricity of the test piece's inner hole.

9. A method for on-machine dressing of a honing head with high cylindricity according to claim 1, characterized in that, In S3 and S4, the trimming cycle can be set to one of the following two modes: time-based trimming duration; distance-based trimming travel length.

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