阅读说明：本技术 一种基于磁流变液的变阻尼变刚度铣削刀架的切削颤振抑制方法 (Cutting chatter suppression method of variable-damping variable-stiffness milling tool rest based on magnetorheological fluid ) 是由 区炳显 王勤生 赵卫芳 刘文俊 熊立斌 于 2021-01-11 设计创作，主要内容包括：本发明属于铣削加工技术领域,具体为一种基于磁流变液的变阻尼变刚度铣削刀架的切削颤振抑制方法,S1：加速度计对刀具的振动情况实时检测,加速度计外接控制器,控制器与励磁线圈连接,控制励磁线圈所在电路的通电和断电；S2：刀具对被加工物料表面切削,刀具作用在被加工物料的外表面,被加工物料对刀具具有反作用力,使得刀具振动。通过加速度计的设置,能够对刀具的振动状态实时监测,从而能够对刀具的状态掌握,在需要调控时及时介入,避免对刀具及被加工物料造成损坏；通过调控筒体、刀架杆、磁流变液、励磁线圈的配合作用,在励磁线圈产生磁场时,使得磁流变液快速固化,使得刀架杆与调控筒体之间连接固定,对刀具起到加固的作用。(The invention belongs to the technical field of milling, and particularly relates to a cutting chatter suppression method of a variable-damping variable-stiffness milling cutter rest based on magnetorheological fluid, which comprises the following steps of S1: the accelerometer detects the vibration condition of the cutter in real time, the accelerometer is externally connected with a controller, and the controller is connected with the excitation coil and controls the power-on and power-off of a circuit where the excitation coil is located; s2: the cutter cuts the surface of the processed material, the cutter acts on the outer surface of the processed material, and the processed material has reaction force to the cutter, so that the cutter vibrates. The vibration state of the cutter can be monitored in real time through the arrangement of the accelerometer, so that the state of the cutter can be mastered, timely intervention is performed when regulation and control are needed, and damage to the cutter and a processed material is avoided; through the cooperation of the regulating cylinder body, the cutter frame rod, the magnetorheological fluid and the magnet exciting coil, when the magnet exciting coil generates a magnetic field, the magnetorheological fluid is quickly solidified, the cutter frame rod and the regulating cylinder body are fixedly connected, and the cutter is reinforced.)

1. A cutting chatter suppression method of a variable-damping variable-stiffness milling cutter rest based on magnetorheological fluid is characterized by comprising the following steps: the cutting chatter suppression method of the variable-damping variable-stiffness milling cutter frame based on the magnetorheological fluid needs to be combined with the following components: the tool comprises a tool (2), a tool rest rod (3), a regulating cylinder (4), an accelerometer (5), an excitation coil (6) and a mounting support rod (7), wherein the four tool rest rods (3) are distributed on the outer wall of the tool (2) at equal angles, one end of each tool rest rod (3) is inserted into the inner cavity of the regulating cylinder (4), magnetorheological fluid is input into the regulating cylinder (4) in advance, the excitation coil (6) is wound on the outer wall of the regulating cylinder (4), the accelerometer (5) is attached to the outer wall of the tool (2), the accelerometer (5) is used for detecting the vibration condition of the tool (2), the mounting support rod (7) is connected to the side wall of the regulating cylinder (4), and the tool (2) and the mounting support rod (7) are both fixedly mounted on;

s1: the vibration condition of the cutter (2) is detected by an accelerometer (5) in real time, the accelerometer (5) is externally connected with a controller, the controller is connected with an excitation coil (6) and controls the power-on and power-off of a circuit where the excitation coil (6) is located, the vibration frequency and amplitude detected by the accelerometer (5) are output to the controller, and whether the vibration condition of the cutter (2) needs to be adjusted or not is judged by the controller;

s2: cutter (2) is to being processed material (1) surface cutting, cutter (2) are used in the surface of being processed material (1), it has reaction force to cutter (2) to be processed material (1), make cutter (2) vibration, when the controller judges that need strengthen to cutter (2) and reduce the vibration, controller control excitation coil (6) circular telegram, excitation coil (6) produce magnetic field after circular telegram, magnetic field is to the inside magnetorheological suspensions effect of control barrel (4), make magnetorheological suspensions solidification tool setting hack lever (3) carry out the fixed action, make four tool hack levers (3) strengthen tool (2).

2. The cutting chatter suppression method of the variable-damping variable-stiffness milling cutter holder based on the magnetorheological fluid, according to claim 1, is characterized in that: a regulation program, a normal vibration frequency and an amplitude value domain are preset in the controller, the accelerometer (5) detects that the vibration frequency and the amplitude of the cutter (2) are compared with the normal vibration frequency and the amplitude value domain, the vibration frequency and the amplitude of the cutter (2) are detected to be in the normal vibration frequency and amplitude value domain, the cutter (2) is considered to vibrate normally, and otherwise, the cutter (2) vibrates abnormally.

3. The cutting chatter suppression method of the variable-damping variable-stiffness milling cutter holder based on the magnetorheological fluid, according to claim 1, is characterized in that: the utility model discloses a regulation barrel, including regulation barrel (4), knife rest pole (3), flexible sealing washer (8), elastic sealing washer (8) are attached on the outer wall of knife rest pole (3), through-groove has been seted up at the lateral wall middle part of regulation barrel (4), knife rest pole (3) run through the groove and extend to the inside of regulation barrel (4), it has flexible sealing washer (8) to lead to the inslot embedding, elastic sealing washer (8.

4. The cutting chatter suppression method of the variable-damping variable-stiffness milling cutter holder based on the magnetorheological fluid, according to claim 1, is characterized in that: the upper side and the lower side of the side wall of the regulating cylinder body (4) are respectively provided with an inlet (9) and an outlet (10), and the inlet (9) and the outlet (10) are communicated with the inner cavity of the regulating cylinder body (4).

5. The cutting chatter suppression method of the variable-damping variable-stiffness milling cutter holder based on the magnetorheological fluid, according to claim 1, is characterized in that: the inner chamber of regulation and control barrel (4) is provided with the baffle, the inner chamber that the baffle will regulate and control barrel (4) is separated for surge bin and storage compartment, and magnetorheological suspensions arranges the storage compartment in, sets up flexible adjustment mechanism in the surge bin, flexible adjustment mechanism's both ends are connected with the inner wall and the baffle of accuse barrel (4) respectively, through flexible adjustment mechanism's flexible effective volume of storage compartment.

Technical Field

The invention relates to the technical field of milling, in particular to a cutting chatter suppression method of a variable-damping variable-stiffness milling cutter rest based on magnetorheological fluid.

Background

In the metal cutting process, a violent self-excited vibration, so-called chatter vibration, often occurs between the tool and the workpiece, which results in a decrease in precision machining efficiency and a decrease in quality of a machined surface, and even damages to the workpiece and the tool, with serious consequences, and therefore, it is necessary to quickly and effectively suppress the machining chatter vibration to improve the quality of the machined surface of the tool. There are two main categories of control strategies for metal cutting chatter: one is a cutting parameter adjustment method, i.e. a machine tool system is positioned in a stable area by selecting or adjusting reasonable cutting parameters; the second category is vibration control methods, i.e., vibration control methods to change the behavior of the system and modify the stability boundaries to avoid chatter vibrations.

For most machine tool systems, the response characteristics are low due to the large rotational inertia of the transmission system, which makes it difficult to achieve large speed variation and rate of change for variable speed cutting. In addition, when the dynamic stiffness of the machine tool system is low, the variable speed cutting method cannot suppress the chatter vibration, and even aggravates the chatter vibration, so that the suppression of the chatter vibration by the variable speed cutting method is still limited in practical application.

Disclosure of Invention

The invention aims to provide a cutting chatter suppression method of a variable-damping variable-stiffness milling cutter rest based on magnetorheological fluid, and aims to solve the problem that for most machine tool systems, the rotational inertia of a transmission system is large, the response characteristic is low, and large speed variation and change rate are difficult to realize in variable-speed cutting. In addition, when the dynamic stiffness of the machine tool system is low, the variable speed cutting method cannot suppress the chatter vibration, and even aggravates the chatter vibration, so that the problem that the variable speed cutting method for suppressing the chatter vibration is limited in practical application is still solved.

In order to achieve the purpose, the invention provides the following technical scheme: a cutting chatter suppression method of a variable-damping variable-stiffness milling cutter frame based on magnetorheological fluid needs to be combined with the following components: the tool comprises a tool, tool rest rods, a regulating cylinder, an accelerometer, an excitation coil and mounting support rods, wherein the tool rest rods are arranged at four equal angles and distributed on the outer wall of the tool;

s1: the method comprises the steps that an accelerometer detects the vibration condition of a cutter in real time, the accelerometer is externally connected with a controller, the controller is connected with an excitation coil and used for controlling the power-on and power-off of a circuit where the excitation coil is located, the vibration frequency and the vibration amplitude detected by the accelerometer are output to the controller, and whether the vibration condition of the cutter needs to be adjusted or not is judged through the controller;

s2: the cutter is to being processed material surface cutting, and the cutter is used in the surface of being processed the material, and the material of being processed has reaction force to the cutter for the cutter vibration, when the controller judges that needs to consolidate the cutter and reduce the vibration, the controller control excitation coil circular telegram, the excitation coil produces magnetic field after circular telegram, and magnetic field is to the magnetorheological suspensions effect of the inside of the regulation barrel of changing, makes the magnetorheological suspensions solidification carry out the fixed action to the cutter saddle pole, makes four cutter saddle poles consolidate the cutter.

Preferably, a regulation program, a normal vibration frequency and a vibration amplitude value range are preset in the controller, the vibration frequency and the vibration amplitude of the cutter detected by the accelerometer are compared with the normal vibration frequency and the vibration amplitude value range, the vibration frequency and the vibration amplitude of the cutter are detected to be in the normal vibration frequency and vibration amplitude value range, the cutter is considered to be normally vibrated, and otherwise, the cutter is abnormally vibrated.

Preferably, a through groove is formed in the middle of the side wall of the regulating cylinder, the cutter support rod penetrates through the through groove and extends to the inside of the regulating cylinder, an elastic sealing ring is embedded in the through groove, and the elastic sealing ring is attached to the outer wall of the cutter support rod.

Preferably, the upper side and the lower side of the side wall of the regulating cylinder are respectively provided with an inlet and an outlet, and the inlet and the outlet are communicated with the inner cavity of the regulating cylinder.

Preferably, the inner chamber of regulation and control barrel is provided with the baffle, the baffle separates the inner chamber of regulation and control barrel for surge bin and storage compartment, and magnetorheological suspensions arranges the storage compartment in, sets up flexible adjustment mechanism in the surge bin, flexible adjustment mechanism's both ends are connected with the inner wall and the baffle of accuse barrel respectively, through the flexible effective volume of adjusting the storage compartment of flexible adjustment mechanism.

Compared with the prior art, the invention has the beneficial effects that:

1) the vibration state of the cutter can be monitored in real time through the arrangement of the accelerometer, so that the state of the cutter can be mastered, timely intervention is performed when regulation and control are needed, and damage to the cutter and a processed material is avoided;

2) through the cooperation of the regulating cylinder body, the cutter frame rod, the magnetorheological fluid and the magnet exciting coil, when the magnet exciting coil generates a magnetic field, the magnetorheological fluid is quickly solidified, the cutter frame rod and the regulating cylinder body are fixedly connected, and the cutter is reinforced.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic view of the connection between the tool and the tool holder bar according to the present invention;

fig. 3 is a schematic structural diagram of the regulating cylinder of the present invention.

In the figure: the device comprises a processed material 1, a cutter 2, a cutter frame rod 3, a regulating cylinder 4, an accelerometer 5, a magnet exciting coil 6, an installation supporting rod 7, an elastic sealing ring 8, an inlet 9 and an outlet 10.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.

Example (b):

referring to fig. 1-3, the present invention provides a technical solution: a cutting chatter suppression method of a variable-damping variable-stiffness milling cutter frame based on magnetorheological fluid needs to be combined with the following components: the tool comprises a tool 2, a tool rest rod 3, a regulating cylinder 4, an accelerometer 5, an excitation coil 6 and a mounting support rod 7, wherein the four tool rest rods 3 are distributed on the outer wall of the tool 2 at equal angles, one end of the tool rest rod 3 is inserted into the inner cavity of the regulating cylinder 4, magnetorheological fluid is input into the regulating cylinder 4 in advance, the excitation coil 6 is wound on the outer wall of the regulating cylinder 4, the accelerometer 5 is attached to the outer wall of the tool 2, the accelerometer 5 detects the vibration condition of the tool 2, the mounting support rod 7 is connected to the side wall of the regulating cylinder 4, and the tool 2 and the mounting support rod 7 are both fixedly mounted on the;

s1: the accelerometer 5 detects the vibration condition of the cutter 2 in real time, the accelerometer 5 is externally connected with a controller, the controller is connected with the excitation coil 6 and controls the power-on and power-off of a circuit where the excitation coil 6 is located, the vibration frequency and amplitude detected by the accelerometer 5 are output to the controller, and whether the vibration condition of the cutter 2 needs to be adjusted or not is judged through the controller;

s2: cutter 2 is to being processed 1 surface cutting of material, cutter 2 is used in the surface by processing material 1, by processing material 1 to cutter 2 have reaction force, make cutter 2 vibration, when the controller judges that needs to strengthen to cutter 2 and reduce the vibration, controller control excitation coil 6 circular telegram, excitation coil 6 produces magnetic field after circular telegram, magnetic field is to the magnetorheological suspensions effect of regulation and control barrel 4 inside, make the magnetorheological suspensions solidification carry out the fixed action to cutter support lever 3, make four cutter support levers 3 to cutter 2 consolidate.

Under the action of an applied magnetic field, the magnetorheological fluid shows the characteristic of non-Newtonian fluid, and the magnetorheological fluid is changed from free flowing liquid into semisolid or even solid within millisecond time, and shows strong controllable rheological property.

The magnetic rheological liquid consists of mainly dispersed particle, dispersoid, base liquid, dispersing medium and additive.

Magnetic particles soft magnetic particles for preparing MRF generally include carbonyl iron powder, Fe3O4, cobalt powder, iron-cobalt alloy, nickel-zinc alloy, composite soft magnetic particles, and the like.

The dispersed particles of the magnetorheological fluid comprise magnetic particles and non-magnetic particles, and the shapes of the dispersed particles are mainly micron-sized and nano-sized spherical ellipsoidal, cylindrical, dumbbell-shaped and regular hexagonal particles. The magnetic particles mainly contain Fe3O4, Fe3N, Fe, Co, Ni and other particles, the magnetic saturation of the iron-cobalt alloy is the largest and reaches 2.4T, carbonyl iron powder and pure iron powder are mostly used in practical application, and the magnetic saturation of the carbonyl iron powder and the pure iron powder is about 2.1T; ② the nonmagnetic particles mainly comprise polymer particles and inorganic nonmetallic particles such as polystyrene and silica particles.

The base liquid is a continuous medium in which the soft magnetic particles can be suspended, and is an important component of the magnetorheological fluid.

Liquids such as synthetic oils, mineral oils, water, and the like may be used as the carrier liquid.The use of colloids as carrier fluids to prepare a magnetorheological elastomer is reported. Fuchs et al prepared a magnetorheological polymer colloid using the polymer colloid as a carrier fluid.

The additive comprises a dispersing agent, an anti-settling agent and the like, and mainly has the effect of improving the settling stability, the redispersibility, the zero field viscosity and the shear yield strength of MRF.

The dispersant mainly comprises oleic acid and oleate, naphthenate, sulfonate, phosphate, stearic acid and its salt, glycerol monooleate, fatty alcohol, silicon dioxide, etc.

The anti-settling agent mainly comprises a high molecular polymer, a hydrophilic silicone resin oligomer, an organic metal silicon copolymer, superfine amorphous silica gel, organic clay, a hydrogen bond-containing oligomer and the like.

Furthermore, Chin uses magnetic particle salts of nanometer scale, glycerol monooleate, fatty alcohols, silica, etc. The anti-settling agent mainly comprises a high molecular polymer, a hydrophilic silicone resin oligomer, an organic metal silicon copolymer, superfine amorphous silica gel, organic clay, a hydrogen bond-containing oligomer and the like.

Further, a regulation program, a normal vibration frequency and a vibration amplitude value range are preset in the controller, the accelerometer 5 detects that the vibration frequency and the vibration amplitude of the cutter 2 are compared with the normal vibration frequency and the vibration amplitude value range, the vibration frequency and the vibration amplitude of the cutter 2 are detected to be in the normal vibration frequency and vibration amplitude value range, the cutter 2 is considered to vibrate normally, and otherwise, the cutter 2 vibrates abnormally.

Furthermore, a through groove is formed in the middle of the side wall of the regulation barrel body 4, the cutter frame rod 3 penetrates through the through groove and extends to the inside of the regulation barrel body 4, an elastic sealing ring 8 is embedded in the through groove, and the elastic sealing ring 8 is attached to the outer wall of the cutter frame rod 3.

Further, the upper side and the lower side of the side wall of the regulating cylinder 4 are respectively provided with an inlet 9 and an outlet 10, and the inlet 9 and the outlet 10 are both communicated with the inner cavity of the regulating cylinder 4.

Further, the inner chamber of regulation and control barrel 4 is provided with the baffle, the baffle separates the inner chamber of regulation and control barrel 4 for surge bin and storage compartment, and magnetorheological suspensions arranges the storage compartment in, sets up flexible adjustment mechanism in the surge bin, flexible adjustment mechanism's both ends are connected with the inner wall and the baffle of accuse barrel 4 respectively, through the flexible effective volume of adjusting the storage compartment of flexible adjustment mechanism.

While there have been shown and described the fundamental principles and essential features of the invention and advantages thereof, it will be apparent to those skilled in the art that the invention is not limited to the details of the foregoing exemplary embodiments, but is capable of other specific forms without departing from the spirit or essential characteristics thereof; the present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein, and any reference signs in the claims are not intended to be construed as limiting the claim concerned.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.