Superhard abrasive forming grinding wheel ultrasonic vibration auxiliary brazing device and operation method thereof

Abstract

The invention provides an ultrasonic vibration auxiliary brazing device for a superhard abrasive formed grinding wheel and an operation method of the ultrasonic vibration auxiliary brazing device, the device comprises a motion control system, an ultrasonic vibration system, a high-frequency induction brazing system and a formed grinding wheel fixing device, and the formed grinding wheel to be brazed is fixed on the fixing device through a spring chuck. The motion control system is composed of a sliding block arranged on the movable guide rail and a motor controlling the sliding block to move and can control the vertical moving speed and direction of the sliding block on the guide rail. The ultrasonic vibration system comprises two ultrasonic vibration amplitude-change poles, a piezoelectric ceramic transducer and an external ultrasonic power supply, each piezoelectric ceramic ultrasonic amplitude-change pole can provide longitudinal vibration, and two-dimensional oval ultrasonic vibration in the brazing process is achieved through synthesis of the longitudinal vibration in the two vertical directions; the motion control system drives the brazing head to move up and down according to the brazing progress, and cooling water circulates in an induction coil of the brazing head. The problems that in the brazing process of the formed grinding tool, brazing filler metal distribution is not uniform, the machining quality is low, the brazing temperature is too concentrated, and the metallurgical reaction is serious in the process are solved.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical processing, and in particular to an ultrasonic vibration assisted brazing device for a superhard abrasive forming grinding wheel and an operating method thereof. Background Art

[0002] Ordinary high-frequency induction brazing is currently one of the commonly used manufacturing methods for superhard abrasive welding. However, due to its concentrated heating area, short heating time, and poor thermal insulation effect, this method easily leads to uneven distribution of abrasive grains on the surface of the abrasive after brazing, thereby reducing the holding strength and exposure height of the abrasive grains. In addition, in the processing of formed abrasives, due to the relatively complex surface structure of the formed abrasives, the irregular flow of the brazing material during the brazing process will aggravate the irregularity of the surface of the abrasive after brazing. At the same time, due to the uneven temperature distribution during the brazing of the formed abrasives, it will lead to more serious metallurgical reactions during the brazing process, affecting the stability of the abrasive grain bond strength on the surface of the formed abrasives.

[0003] Ultrasonic vibration assisted brazing is a brazing method that uses the cavitation and acoustic streaming effects of ultrasound in liquid brazing material to cause local high temperature and high pressure as well as micro jets to achieve material connection. The cavitation effect refers to periodically changing ultrasound, which causes the pressure field in the liquid brazing material to alternate between positive and negative pressures. When under negative pressure, the tiny bubbles in the liquid brazing material will be stretched, and when under positive pressure, the bubbles will be crushed. In this process, high temperature and high pressure and micro jet phenomena will appear at the local location where the bubbles are located. The ultrasonic cavitation effect during brazing can effectively spread the brazing material on the surface of the mold, improve the problems of welds on the surface of the mold, uneven distribution of brazing material, insufficient holding force on the abrasive particles, and poor abrasive properties during brazing. The use of specific ultrasonic vibration modes for high-frequency brazing of formed grinding wheels can achieve better grinding performance.

[0004] The invention patent application with the publication number CN113539866A applied by Southwest Jiaotong University discloses a method for preparing memristors by ultrasonic assisted brazing. First, the intermediate dielectric layer is prepared by "one-step" anodic oxidation, and the pure titanium sheet is pre-treated. Then, an electrolyte is prepared, and a platinum sheet is used as the cathode and a titanium sheet is used as the anode. The oxidation is carried out at a DC voltage of 60 V for 2 h to obtain titanium oxide nanotubes. Then, the top electrode is prepared by ultrasonic assisted brazing. The pure Sn solder is placed at one end of the Al sheet and the whole is heated to 280 °C. When the pure Sn solder melts, ultrasonic waves are applied to the other side of the Al sheet. The ultrasonic frequency is 20 kHz, the power is 700 W, and the amplitude is 2μm. The first ultrasonic application time is 0.1 s, and the second ultrasonic application time is 2 s. The ultrasonic waves are applied multiple times until the solder fills the seam. The preparation of the memristor device of the top electrode / TiO2 / Ti is realized based on the ultrasonic assisted brazing method. The operation is simple and has the unique resistance switching characteristics of the memristor.

[0005] The invention patent application with the publication number CN109759741A applied by Chongqing University of Technology discloses a brazing powder for ultrasonic assisted brazing and a brazing method. The invention provides a brazing powder for ultrasonic assisted brazing and a brazing method, wherein the brazing powder is uniformly mixed with tin-copper powder or tin-silver-copper powder, or a mixture of tin-copper powder and tin-silver-copper powder, and any one, or any two, or any three, or any four, or five of nickel powder, cobalt powder, copper powder, tin powder, and titanium powder with active nanoparticles in the range of 1-1 000 nm in diameter, at a mass ratio not exceeding 20%. The brazing powder and brazing method for ultrasonic assisted brazing of the present invention have low welding temperature, use active nanoparticles, generate heat through the oscillation of an ultrasonic generator, promote metallurgical reaction between the solder or nanoparticles and the base material, and realize low-temperature interconnection of lead-free solder in full solid phase or semi-solid phase. The welding temperature is more than 30°C lower than that of traditional liquid interconnection. The oscillation activation and friction generated by the ultrasonic generator promote the rupture of the oxide film on the surface of the welding base material, achieve the effect of film removal, reduce gas pollution generated by the welding flux, reduce welding pollution, and have high joint quality.

[0006] The invention patent application with the publication number CN113000967A applied by Beijing Institute of Technology discloses a method and device for ultrasonic-assisted high-frequency brazing of micro-sized super-hard tools. The welding method is to first precisely clamp the tool head and tool handle, then turn on the measuring device, then start the ultrasonic vibrator, and perform high-frequency brazing under the assistance of ultrasound, and finally close the entire device and remove the welded super-hard tool. The ultrasonic-assisted brazing device for micro-sized super-hard tools consists of four parts: a clamping device, a measuring device, an ultrasonic-assisted device, and a high-frequency brazing device. The tool handle and tool head are precisely clamped by the clamping device, and the measuring device performs real-time temperature and pressure measurement. The ultrasonic-assisted high-frequency brazing technology is used to improve the brazing quality of micro-sized super-hard tools. It has a simple structure and is easy to operate, which greatly improves the welding performance of micro-sized super-hard tools.

[0007] At present, the brazing process is widely used in the welding of various superhard abrasives, but there are few methods and devices for ultrasonic vibration-assisted induction brazing of grinding tools, especially for the processing methods of formed grinding wheels. The ultrasonic vibration-assisted induction brazing device for a single vibration direction has a single vibration mode, which is effective for the improvement of the grinding tool, and the grinding head with different shank diameters needs to be frequently replaced, which greatly reduces the processing efficiency. Therefore, it is urgent to develop a two-dimensional ultrasonic vibration-assisted induction brazing device for formed grinding wheels. Summary of the invention

[0008] In order to solve the problem that the existing ordinary brazing and single vibration direction ultrasonic brazing devices are insufficient to improve the grinding performance of superhard abrasive tools, the present invention designs an ultrasonic vibration assisted brazing device for superhard abrasive forming grinding wheels and an operating method thereof. The device has a simple assembly structure and good induction brazing efficiency, and is suitable for two-dimensional ultrasonic vibration assisted brazing of various forming grinding wheels.

[0009] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention is: An ultrasonic vibration assisted brazing device for super-hard abrasive formed grinding wheels comprises a motion control system, an ultrasonic vibration system, a high-frequency induction brazing system and a fixing device for the formed grinding wheel. The formed grinding wheel to be brazed is fixed to the center of the base by a spring chuck placed in a cylindrical groove in the center of a support base.

[0010] The motion control system consists of a slider placed on a moving guide rail and a motor that controls its movement. The motor is connected to a PLC control system of a computer, which can control the speed and direction of the slider moving up and down on the guide rail, thereby ensuring that the coil maintains a suitable movement direction and speed during the brazing process.

[0011] The ultrasonic vibration system includes two ultrasonic vibration amplitude transformers, a piezoelectric ceramic transducer, and an amplitude transformer support base. The two ultrasonic vibration amplitude transformers are respectively connected to the positive and lateral directions of the support base. There is a groove in the center of the amplitude transformer support base. The amplitude transformer is combined with the groove through a flange. The amplitude transformer support base is connected to the vibration-proof base plate through bolts, and the piezoelectric ceramic transducer is connected to the large end of the amplitude transformer through bolts and the rear cover plate.

[0012] The aforementioned ultrasonic vibration assisted high-frequency induction brazing superhard abrasive forming grinding wheel device has two threaded sleeves connected to the two sides of the base supporting the forming grinding wheel, and the small end of the piezoelectric ceramic ultrasonic amplitude transformer is provided with a corresponding matching thread for connecting the amplitude transformer and the base.

[0013] The aforementioned ultrasonic vibration-assisted high-frequency induction brazing superhard abrasive forming grinding wheel device has a cylindrical groove connected to the bottom in the center of the base supporting the forming grinding wheel. The bottom plate inside the cylindrical groove is processed with a conical hole matching the spring chuck and there is a protruding cylindrical section with a thread on the outside for fixing the spring chuck with a nut; the spring chuck can be adjusted to adapt to forming grinding wheels of various sizes.

[0014] The aforementioned ultrasonic vibration-assisted high-frequency induction brazing super-hard abrasive forming grinding wheel device has a pair of air inlets 31 on the side of the protective cover, which are externally connected to an argon gas pipe. During the induction brazing process, argon protective gas is introduced through the air inlet, and an air outlet 32 ​​is opened on the other side for gas discharge and circulation; a pair of threaded holes are opened at the bottom of the protective cover, and the protective cover can be connected to the circular groove in the center of the base by bolts through the threaded holes, so as to be fixed on the support base. The top of the protective cover is threaded for connection with the protective cover, which is divided into a main protective cover and a smaller auxiliary protective cover to accommodate forming grinding wheels of different sizes during the induction brazing process.

[0015] The aforementioned ultrasonic vibration assisted high-frequency induction brazing superhard abrasive forming grinding wheel device, the high-frequency induction brazing system is mainly composed of a brazing head and an induction coil connected to a high-frequency brazing machine, the induction coil is connected to the brazing head by soldering, the brazing head is fixed to the supporting plate on the movable slider of the guide rail by bolts through two protruding threaded holes, the coil is hollow inside, and is connected to the external cooling water circulation system through the brazing head.

[0016] The method for ultrasonic vibration assisted brazing of superhard abrasive forming grinding wheels based on the above-mentioned ultrasonic vibration assisted high-frequency induction brazing superhard abrasive forming grinding wheel device comprises the following steps: (1) Start the PLC control system connected to the motor and set the appropriate motor movement direction and speed during induction brazing.

[0017] (2) Turn on the external water pump and allow the cooling water to circulate in the induction coil for several minutes until the cooling water circulates smoothly.

[0018] (3) Fix the molded grinding wheel to be brazed with a spring chuck at the center of the support base, and turn on the ultrasonic power supply connected to the ultrasonic vibration system. The piezoelectric ceramic transducer converts the electrical signal into mechanical vibration, which drives the amplitude transformer to vibrate. The amplitude transformer transmits the vibration to the support base platform through the small end, thereby causing the molded grinding wheel to vibrate accordingly during the brazing process. According to the vibration mode requirements of brazing, the ultrasonic power supply connected to one or two corresponding ultrasonic amplitude transformers can be selectively turned on.

[0019] (4) High-purity argon gas is continuously introduced through the air inlet and outlet of the protective cover for several minutes until the original air inside the protective cover is discharged. The PLC control system is used to control the induction coil to enter the appropriate brazing position of the protective cover, start the high-frequency induction brazing machine, continuously increase the brazing current, maintain cooling water circulation, and after the brazing material melts, the PLC control system is used to raise the induction coil to avoid overheating during the brazing process. The sealing gasket inside the protective cover can play a good sealing role. Beneficial Effects

[0020] (1) In the device provided by the present invention, a high-frequency induction brazing head is installed on a movable slider, which drives the brazing head to move along the guide rail of the movable table. The slider is controlled by a motor connected to a PLC system, so that a scanning brazing method can be realized during the induction brazing process, thereby reducing defects such as loss of brazing material on the surface of the forming grinding wheel after brazing and reduced holding force due to excessive concentration of the brazing temperature and untimely cooling.

[0021] (2) In the device provided by the present invention, the forming grinding wheel is clamped by an adjustable spring chuck fixed to the center of the support base. The adjustability of the spring chuck can adapt to clamping forming grinding wheels of different sizes, thereby avoiding the frequent replacement of the corresponding device due to the size change of the brazed forming grinding wheel.

[0022] (3) In the device provided by the present invention, ultrasonic vibration is applied to the support platform through a piezoelectric ceramic ultrasonic transformer, and in combination with a scanning induction brazing method, the fluidity of the brazing material during the brazing process can be increased, and the uneven heating of the brazing material can be reduced. Through the cavitation effect of ultrasonic vibration, the bubbles inside the brazing material when it is combined with the substrate after brazing are reduced, the spreadability of the brazing material is improved, and the processing performance of the formed grinding wheel after brazing is improved.

[0023] (4) In the device provided by the present invention, two piezoelectric ceramic ultrasonic horn rods connected to the front and side surfaces are used to realize an ultrasonic vibration type that can be changed during the induction brazing process. According to the different structures of the induction brazing forming grinding wheel, one piezoelectric ceramic ultrasonic horn rod can be selected to realize one-dimensional longitudinal vibration or two piezoelectric ceramic ultrasonic horn rods can be selected to realize two-dimensional elliptical vibration, thereby improving the applicability of the overall ultrasonic vibration system. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is an overall schematic diagram of an ultrasonic vibration assisted brazing device for super-hard abrasive forming grinding wheels of the present invention; Figure 2 is a schematic diagram of a mobile station; Figure 3 is a schematic diagram of an induction brazing device 3; Figure 4 is a schematic diagram of a piezoelectric ceramic ultrasonic system; Figure 5 is a schematic diagram of the horn bracket 8; Figure 6 is a three-dimensional schematic diagram of the molding grinding wheel support base 10; Figure 7 for Figure 6 A front view of Figure 8 is a schematic diagram of a spring chuck; Fig. 9 It is a schematic diagram of the argon gas protective cover; Fig.10It is a schematic diagram of the main protective cover; Fig.11 is a schematic diagram of the secondary protective cover; Fig.12 This is a schematic diagram of the brazing effect after ultrasonic vibration assisted brazing; Fig.13 A detailed schematic diagram of the dispersion of the abrasive tool to be brazed, the argon protective cover, etc. Fig.14 Schematic diagram of the mode and ultrasonic vibration direction of the piezoelectric ceramic horn shown above at the operating frequency.

[0025] Among them, the movable platform guide rail-1, the control motor-2, the induction brazing device-3, the induction coil-4, the piezoelectric ceramic amplitude transformer I-5, the piezoelectric ceramic amplitude transformer II-7, the protective cover-6, the amplitude transformer bracket-8, the argon protective cover-9, the forming grinding wheel support base-10, the anti-vibration bottom plate-11, the platform support rib-12, the fixed bracket-13, the threaded hole-14, the induction brazing device brazing head-15, the induction coil connector-16, the bolt-17, the rear cover plate-18, the piezoelectric ceramic sheet-1 9. Electrode sheet-20, flange-21, amplitude transformer-22, connecting thread-23, connecting groove-24, threaded hole-25, cylindrical groove-26, connecting thread sleeve I-27, connecting thread sleeve II-28, threaded hole-29, threaded hole-30, air inlet-31, air outlet-32, connecting thread-33, high-frequency induction brazing machine-34, PLC control system-35, ultrasonic power supply-36, external cooling water circulation system-37, water tank-38, water pump-39. DETAILED DESCRIPTION

[0026] The technical solution of the present invention will be specifically described below in conjunction with specific embodiments:

[0027] Example

[0028] Figure 1 This is a schematic diagram of an ultrasonic vibration assisted brazing device for super-hard abrasive forming grinding wheels according to the present invention. Figure 1 As shown, the device includes: a motion control system, a high-frequency induction brazing system, an ultrasonic vibration system, and a molding grinding wheel fixing system, and the bottoms of the above systems are fixed on the anti-vibration bottom plate 11. Among them, the motion control system includes a moving platform, a moving platform guide rail 1, and a slider 2 controlled by a motor, and the motor is externally connected to a computer PLC program; the high-frequency induction brazing system includes an induction brazing device 3, an induction coil 4, and an external high-frequency induction brazing machine and a cooling water circulation system; the ultrasonic vibration system includes a piezoelectric ceramic ultrasonic horn Ⅰ5, a piezoelectric ceramic ultrasonic horn Ⅱ7, an ultrasonic horn bracket 8, and an external ultrasonic power supply; the molding grinding wheel fixing system includes an argon protective cover 9 and a support base 10. The bottoms of the guide rail 1, the ultrasonic horn bracket 8, and the support base 10 are all fixed on the anti-vibration bottom plate 11.

[0029] The ultrasonic vibration system transmits the amplified longitudinal vibration to the support base platform of the molding grinding wheel fixing system through two mutually perpendicular horns, so that the molding grinding wheel in the brazing process produces two-dimensional elliptical vibration. The motion control system drives the induction coil 4 of the high-frequency induction brazing system to move up and down in the argon protective cover of the molding grinding wheel fixing system according to the brazing progress. During the brazing process, the cold water of the cooling water circulation system flows in the induction coil 4 to achieve real-time cooling.

[0030] Figure 2 It is a schematic diagram of a movable table, in which the movable table guide rail and the slider 2 are movably connected in an interlocking manner, wherein the slider 2 is connected to the PCL system control system 35, and the slider slides in the guide rail under the control of the PCL system control system 35. A supporting platform for connecting a high-frequency brazing head is provided on the top of the slider 2, and a platform supporting rib 12 is provided between the platform and the side wall of the slider, and a pair of protruding brackets 13 are provided on the platform, which have threaded holes for connecting with the brazing head.

[0031] Figure 3 The figure is a schematic diagram of the induction brazing device brazing head 15. The bottom of the induction brazing device brazing head 15 is bolted to the induction coil connector 16, and a sealing gasket is disposed at the connection part. The induction coil 4 is connected to the induction coil connector 16 by soldering. Among them, the threaded hole 14 on the side of the induction brazing device brazing head 15 is connected to the above-mentioned bracket 13 by bolts and threaded holes to fix the induction brazing device to the slider. Under the control of the PCL system control system 35, the slider drives the induction brazing device brazing head to move up and down. The induction brazing device brazing head is connected to the high-frequency induction brazing machine 34 and the external cooling water circulation system 37. The induction coil is hollow inside, and cooling water from the external cooling water circulation system is passed inside during the brazing process to ensure the normal temperature of the induction coil during the induction brazing process.

[0032] Figure 4 The figure is a schematic diagram of a piezoelectric ceramic amplitude transformer, which includes an amplitude transformer and a transducer. The transducer is composed of piezoelectric ceramic sheets 19, electrode sheets 20, a rear cover plate 18 and bolts 17, wherein four electrode sheets are sandwiched between five piezoelectric ceramic sheets, which are pressed by bolts 17 and the rear cover plate 18, and connected to the large end of the amplitude transformer through threaded holes at the rear end of the amplitude transformer. The amplitude transformer is a stepped amplitude transformer 22, wherein the large end and the small end are cylinders of different diameters, and the middle part is connected by a transition of the cylinder, and a flange 21 is provided at the vibration node, which is connected to the flange 21 through the flange 21. Figure 5The connecting groove 24 of the ultrasonic horn bracket is matched, and the bracket is connected to the anti-vibration base plate 11 through the threaded hole 25 at the bottom. The small end of the horn has a thread 23 for connecting to the support base platform. In this embodiment, the number of piezoelectric ceramic horn is two, which are respectively arranged on the front and side of the support base platform to achieve two-dimensional elliptical vibration. The reason why the horn is not arranged in a relative manner in the present invention is that the relative arrangement will cause the amplitude to be offset or weakened in the transverse wave direction.

[0033] Figure 6 This is a schematic diagram of the support base for the forming grinding wheel. Figure 7 As shown in its front view, an arc-shaped groove is opened in the center of the support base, and a conical hole matching the spring chuck is processed in the bottom plate inside the groove and there is a protruding cylindrical section with a thread on the outside for cooperating with a nut to fix the spring chuck used to clamp the forming mold; a connecting threaded sleeve I 27 and a connecting threaded sleeve II 28 are respectively opened on the front and side of the top platform of the support base to connect the above-mentioned two piezoelectric ceramic amplitude transformers, and a pair of threaded holes 29 are opened in the convex cylindrical groove in the center to fix the argon protection cover, and O-rings are arranged between the argon protection cover and the cylindrical groove.

[0034] Figure 8 The spring chuck is a schematic diagram. The size of the spring chuck can be adjusted to adapt to different sizes of forming grinding wheels. The overall shape and size match the groove in the center of the forming grinding wheel support base. Before brazing, the small end of the spring chuck is used to clamp the forming grinding wheel, and the large end is placed downward in the groove of the support base. Then the protective cover is installed on the forming grinding wheel support base. With the help of the protective cover and the protective cover, the forming grinding wheel is placed in a closed space. The induction coil is extended into the protective cover through the hole on the top of the main protective cover to implement brazing of the grinding wheel.

[0035] Fig. 9 It is a schematic diagram of an argon protective cover. A threaded hole 30 is provided on the side wall near the bottom, which is fixed to the threaded hole 29 of the above-mentioned molding grinding wheel support base by bolts to connect the above-mentioned support base. A pair of air inlets 31 are opened on the side wall near the top of the argon protective cover, and a corresponding air outlet 32 ​​is opened on the other side. During the induction brazing process, high-purity argon gas is continuously introduced from the air inlet and outlet to ensure that the molding grinding wheel substrate is not oxidized during the brazing process. There is a thread 33 on the top of the protective cover to match the protective cover.

[0036] Fig.10 This is a schematic diagram of the main protective cover, which is fixed to the argon protective cover with the help of the internal thread at the bottom, and the top is provided with an external thread for connecting the smaller secondary protective cover. Fig.11The diagram of the secondary protective cover is used to seal a smaller protective cover. During induction brazing, you can choose to unscrew the main protective cover or the secondary protective cover according to the size of the corresponding brazing forming grinding wheel. Remove the secondary protective cover, and the coil enters the protective cover through the opening for brazing. If the coil size is too large, you can also directly remove the main protective cover and directly insert it into the protective cover for brazing.

[0037] The method for ultrasonic vibration assisted brazing of superhard abrasive forming grinding wheels based on the above-mentioned ultrasonic vibration assisted high-frequency induction brazing superhard abrasive forming grinding wheel device comprises the following steps: (1) Start the PLC control system connected to the motor and set the appropriate motor movement direction and speed during induction brazing.

[0038] (2) Turn on the external water pump and allow the cooling water to circulate in the induction coil for several minutes until the cooling water circulates smoothly.

[0039] (3) Fix the molded grinding wheel to be brazed with a spring chuck and place it in the groove in the center of the support base, fix the protective cover and the protective cover; turn on the ultrasonic power supply connected to the ultrasonic vibration system, and the piezoelectric ceramic transducer converts the electrical signal into mechanical vibration, which drives the amplitude transformer to vibrate. The amplitude transformer transmits the vibration from the front and / or side to the support base platform through the small end, so that the molded grinding wheel in the brazing process produces two-dimensional vibration. According to the vibration mode requirements of brazing, the ultrasonic power supply connected to one or two corresponding ultrasonic amplitude transformers can be selectively turned on.

[0040] (4) High-purity argon gas is continuously introduced through the air inlet and outlet of the protective cover for several minutes until the original air inside the protective argon cover is exhausted. The PLC control system is used to control the induction coil to enter the appropriate brazing position of the protective cover, start the high-frequency induction brazing machine, continuously increase the brazing current, and maintain cooling water circulation. After the brazing material is melted, the PLC control system is used to move the slider in the guide rail of the mobile table to raise the induction coil to avoid overheating during the brazing process. The sealing gasket in the protective cover can play a good sealing role. Fig.12 The comparison shows the effect of the bonding between the brazing filler metal and the abrasive grains on the surface of the forming grinding wheel before and after the application of ultrasonic vibration assistance. It can be seen that the cavitation effect of the two-dimensional elliptical ultrasonic vibration reduces the bubbles inside the brazing filler metal when it is bonded to the substrate after brazing, and improves the spreadability of the brazing filler metal. Moreover, the brazing filler metal is evenly distributed, and the brazing temperature is evenly distributed.

[0041] The contents described in the embodiments of the present invention are merely simple examples of implementation forms of the inventive concept. The protection scope of the present invention should not be limited to the specific forms described in the embodiments. All simple modifications made according to the present invention should be within the protection scope of the present invention.

Claims

1. A super-hard abrasive forming grinding wheel ultrasonic vibration assisted brazing device, characterized in that: include: A motion control system, a high-frequency induction brazing system, an ultrasonic vibration system, and a molding grinding wheel fixing system, wherein the bottoms of the above-mentioned systems are fixed on a vibration-proof bottom plate (11); the ultrasonic vibration system transmits the amplified longitudinal vibration to the support base platform of the molding grinding wheel fixing system through two amplitude change rods arranged perpendicular to each other, thereby causing the molding grinding wheel to generate two-dimensional elliptical vibration during the brazing process; the motion control system drives the induction coil 4 of the high-frequency induction brazing system to move up and down in the argon protective cover of the molding grinding wheel fixing system according to the progress of the brazing; during the brazing process, cold water of the cooling water circulation system flows in the induction coil (4) to achieve real-time cooling.

2. The ultrasonic vibration assisted brazing device for superhard abrasive forming grinding wheels according to claim 1, characterized in that: The motion control system comprises a moving platform, a moving platform guide rail (1) and a slider (2) controlled by a motor, and the motor is externally connected to a PCL system control system (35); the moving platform guide rail and the slider (2) are movably connected in an engaging manner, and the slider slides in the guide rail under the control of the PCL system control system; The high-frequency induction brazing system comprises an induction brazing device (3) and an external high-frequency induction brazing machine and a cooling water circulation system; one end of the induction coil (4) on the brazing head of the induction brazing device extends into the molding grinding wheel fixing system, and cooling water circulates in the coil for real-time cooling; The ultrasonic vibration system comprises a transducer, two piezoelectric ceramic ultrasonic horns, an ultrasonic horn bracket (8) and an external ultrasonic power supply; The molding grinding wheel fixing system comprises an argon protective cover (9) and a support base (10), wherein a groove is provided at the center of a panel of the support base (10), a spring chuck for clamping the molding grinding wheel is placed in the groove, and the protective cover is used to achieve sealing during the brazing process; The bottom of the mobile platform, the ultrasonic horn bracket (8) and the supporting base (10) are fixed on the anti-vibration base plate.

3. The ultrasonic vibration assisted brazing device for super-hard abrasive forming grinding wheels according to claim 2, characterized in that: The transducer includes piezoelectric ceramic sheets, electrode sheets, a rear cover plate and bolts, wherein four electrode sheets are sandwiched between five piezoelectric ceramic sheets, which are pressed by bolts and the rear cover plate, and connected to the large end of the amplitude transformer through threaded holes at the rear end of the amplitude transformer.

4. The ultrasonic vibration assisted brazing device for super-hard abrasive forming grinding wheels according to claim 2, characterized in that: The horn is a stepped horn, the large end and the small end are cylinders of different diameters, the middle part is connected by a cylindrical transition, a flange (21) is provided at the vibration node, the flange is matched with the connection groove (24) of the ultrasonic horn bracket, and the small end of the horn is connected to the support base platform by a thread; the number of the horn is two, which are respectively arranged on the front and side of the support base platform to realize two-dimensional elliptical vibration.

5. The ultrasonic vibration assisted brazing device for super-hard abrasive forming grinding wheels according to claim 1, characterized in that: The upper panel of the support base has a central opening, and a groove is provided between the upper and lower panels. The shape and size of the groove match the spring chuck used to clamp the forming mold, and the two are fixed by threads. Connecting threaded sleeves are provided on the front and side surfaces of the upper panel of the support base to connect the two amplitude rods, and a threaded hole (29) is provided on the protruding connecting piece of the central opening to fix the argon protective cover.

6. The ultrasonic vibration assisted brazing device for super-hard abrasive forming grinding wheels according to claim 5, characterized in that: Before brazing, the small end of the spring chuck is used to clamp the formed grinding wheel, and the large end is placed downward in the groove of the support base. The protective cover is installed above the groove to construct a closed space. The induction coil extends into the protective cover through the hole on the top of the protective cover to implement brazing of the grinding wheel.

7. The ultrasonic vibration assisted brazing device for super-hard abrasive shaping grinding wheels according to claim 5, characterized in that: A threaded hole (30) is provided on the side wall of the protective cover near the bottom, and is fixed to the threaded hole (29) of the above-mentioned molding grinding wheel support base by bolts to connect the above-mentioned support base. A pair of air inlets are opened on the side wall of the protective cover near the top, and a corresponding air outlet is opened on the other side. During the induction brazing process, high-purity argon gas is continuously introduced from the air inlet and outlet to ensure that the molding grinding wheel substrate is not oxidized during the brazing process.

8. The ultrasonic vibration assisted brazing device for super-hard abrasive forming grinding wheels according to claim 2, characterized in that: A support platform for connecting a high-frequency brazing head is provided on the top of the slider (2), a platform support rib (12) is provided between the platform and the side wall of the slider, and a pair of protruding brackets (13) are provided on the platform, with threaded holes formed thereon for connecting with the brazing head.

9. The method for operating the ultrasonic vibration-assisted brazing device for super-hard abrasive shaping grinding wheels according to claim 1, characterized in that: Here are the steps: (1) Start the PLC control system connected to the motor and set the appropriate motor movement direction and speed during induction brazing; (2) Turn on the external water pump to allow the cooling water to circulate in the induction coil for several minutes until the cooling water circulates smoothly; (3) Fix the molded grinding wheel to be brazed with a spring chuck and place it in the groove in the center of the support base, and fix the protective cover and the protective cover; turn on the ultrasonic power supply connected to the ultrasonic vibration system, and the piezoelectric ceramic transducer converts the electrical signal into mechanical vibration, which drives the amplitude transformer to vibrate. The amplitude transformer transmits the vibration to the support base platform from the front and / or side through the small end, thereby causing the molded grinding wheel to generate two-dimensional vibration during the brazing process; according to the vibration mode requirements of brazing, the ultrasonic power supply connected to one or two corresponding ultrasonic amplitude transformers can be selectively turned on; (4) High-purity argon gas is continuously introduced through the air inlet and outlet of the protective cover until the original air is exhausted. The PLC control system is used to control the induction coil to enter the appropriate brazing position of the protective cover, start the high-frequency induction brazing machine, continuously increase the brazing current, and maintain cooling water circulation. After the brazing material is melted, the PLC control system is used to move the slider in the guide rail of the movable table to lift the induction coil to avoid overheating during the brazing process.

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