Radial ultrasonic-assisted micro-forging surface strengthening device

Abstract

The invention provides a radial ultrasonic-assisted micro-forging surface strengthening device, and relates to the field of machining, and the radial ultrasonic-assisted micro-forging surface strengthening device is characterized in that a micro-forging system is used for generating low-frequency large-amplitude impact motion, and an ultrasonic impact system is used for generating high-frequency small-amplitude impact motion; and axial output generated by the micro-forging system is compounded with radial output generated by the ultrasonic peening system. The punch, the ultrasonic connecting piece and the horizontal sliding block are sequentially connected and are driven by the connecting rod to do radial motion, and the ultrasonic connecting piece, the vertical sliding block and the ultrasonic amplitude-change pole are sequentially connected and are driven to do axial motion. The micro-forging system and the ultrasonic impact system are combined, the axial low-frequency large-stroke impact motion (hundreds of hertz and millimeter-level stroke) of the punch driven by the electromagnetic system and the radial high-frequency small-stroke impact motion (tens of thousands of hertz and micron-level stroke) driven by the ultrasonic system are achieved at the same time, and parts are strengthened more effectively.

Description

Technical Field

[0001] The present application relates to the field of processing, and in particular, to a radial ultrasonic-assisted micro-forging surface strengthening device. Background Art

[0002] Micro-forging is an emerging mechanical surface modification process that involves using a high-hardness hammer with high frequency oscillation to hammer the target area. The structure of a typical micro-forging device is as follows: Figure 1 As shown, the impact structure performs reciprocating linear motion between the limit block and the workpiece surface under the stimulation of the drive system. After the material is subjected to the continuous impact of protons, strong plastic deformation occurs. A certain plastic deformation can improve the surface integrity of the material. The control system can be used to adjust the impact frequency and impact energy, and the cooling system dissipates heat and ensures the stable operation of the system. The micro-forging device is generally installed at the end of the machine tool or the robotic arm through a mechanical interface to adjust the process parameters such as stroke, step distance, line distance, and impact angle. During the processing, the micro-forging head always maintains a constant distance from the workpiece surface to ensure that the workpiece material is subjected to an impact with precise position and uniform intensity. The surface finishing or strengthening of workpieces made of different metal materials can be achieved through precise high-frequency impact.

[0003] Ultrasonic impact technology is an efficient method to eliminate harmful residual tensile stress on the surface of components and introduce beneficial compressive stress. Typical ultrasonic micro-forging impact equipment is shown below: Figure 2 As shown, it is mainly composed of four parts: ultrasonic generator, ultrasonic transducer, amplitude rod and impact head. The ultrasonic generator is a high-frequency circuit that generates high-frequency electrical energy. The ultrasonic transducer converts the high-frequency electrical energy into mechanical vibration, which is then amplified by the amplitude rod. Finally, the mechanical vibration is transmitted to the impact head. The impact head contacts the workpiece and transmits the ultrasonic vibration to the surface of the workpiece to achieve a strengthening effect.

[0004] The ultrasonic generator generates a high-frequency ultrasonic impact device that uses high-power energy to drive the impact head to impact the surface of the metal object at a frequency of about 20,000 times per second. The high frequency, high efficiency and high energy under focus cause the metal surface to produce a large compressive plastic deformation; at the same time, the ultrasonic impact changes the original stress field and produces beneficial compressive stress; under high-energy impact, the temperature of the metal surface rises rapidly and then cools rapidly, causing the surface metal structure of the action area to change and the impact site to be strengthened.

[0005] The study found that through axial micro-forging impact combined with radial ultrasonic vibration, greater plastic deformation of the material can be achieved, better grain refinement and better strengthening effect on parts can be achieved.

[0006] However, at present, only a relatively single process is used to strengthen materials and parts. Whether it is micro-forging or ultrasonic impact, the plastic deformation and strengthening effect of a single process on the part material are limited. There is no corresponding process and device that can simultaneously achieve micro-forging and ultrasonic impact on parts. There is a lack of corresponding equipment and methods to achieve composite strengthening combining axial micro-forging impact and radial ultrasonic impact to improve the strengthening effect of parts.

[0007] The existing Chinese patent with publication number CN117920925A discloses an electromagnetic micro-forging device with active stroke adjustment, including an upper limit active adjustment structure and an electromagnetic micro-forging drive structure; the electromagnetic micro-forging drive structure includes a first housing, a drive assembly, an intermediate connecting rod and a micro-forging head; the micro-forging head is installed at the bottom end of the intermediate connecting rod, and the drive assembly is used to drive the intermediate connecting rod to reciprocate up and down; the upper limit active adjustment structure is installed above the electromagnetic micro-forging drive structure, and is used to adjust the highest position of the reciprocating motion of the intermediate connecting rod. The upper limit active adjustment structure includes an active adjustment structure drive member, a transmission member, a screw rod and a movable upper limit block; the prior art can actively adjust the position of the movable upper limit block through the design of the upper limit active adjustment structure to achieve the adjustable upper limit position of the intermediate connecting rod, thereby controlling the stroke of the micro-forging and achieving the purpose of online regulation of the micro-forging effect.

[0008] However, the disadvantage of the prior art is that it uses a relatively single process to strengthen the material, the punch action direction is limited to the axial direction, and it is impossible to achieve multi-degree-of-freedom surface strengthening. At the same time, it has not been possible to combine micro-forging with ultrasonic impact technology to improve the strengthening effect. Summary of the invention

[0009] In view of the defects in the prior art, the purpose of the present application is to provide a radial ultrasonic assisted micro-forging surface strengthening device.

[0010] A radial ultrasonic-assisted micro-forging surface strengthening device provided by the present application includes: a micro-forging system and an ultrasonic impact system, wherein the micro-forging system is used to generate low-frequency large-amplitude impact motion, and the ultrasonic impact system is used to generate high-frequency small-amplitude impact motion; the axial output generated by the micro-forging system is combined with the radial output generated by the ultrasonic impact system.

[0011] Specifically, it includes: a micro-forging housing, an ultrasonic connector, a horizontal slider, a vertical slider, a punch and a spring. The horizontal slider is installed between the ultrasonic connector and the output end of the micro-forging system, and the micro-forging system drives the ultrasonic connector and the punch to move axially;

[0012] The vertical slide block is installed between the ultrasonic connector and the output end of the ultrasonic impact system. The ultrasonic impact system drives the ultrasonic connector and the punch to move radially. The spring is used to reset both the punch and the ultrasonic connector.

[0013] Preferably, the low-frequency large-amplitude impact motion is hundreds of hertz and millimeter-level stroke motion; the high-frequency small-amplitude impact motion is tens of thousands of hertz and micrometer-level stroke motion.

[0014] Preferably, the micro-forging system comprises a driving assembly, and the driving assembly is drivingly connected to an output shaft of the micro-forging system; the driving assembly comprises a pneumatic driving assembly, a piezoelectric driving assembly or an electromagnetic driving assembly.

[0015] Preferably, the electromagnetic drive assembly comprises: a permanent magnet, a coil support and an excitation coil, the permanent magnet is fixedly mounted on the micro-forging housing, the excitation coil is wound on the coil support, and the excitation coil is coupled to the permanent magnet; a connecting rod is connected to the coil support as the output shaft of the micro-forging system.

[0016] Preferably, an upper limit block is provided at one end of the micro-forging shell axially away from the punch, and the upper limit block limits the axial displacement of the connecting rod; and a mechanical interface is provided on the top of the upper limit block.

[0017] Preferably, the ultrasonic impact system includes an ultrasonic shell, an ultrasonic generator, an ultrasonic transducer and an ultrasonic horn, both of which are located inside the ultrasonic shell, the ultrasonic generator is connected to the ultrasonic transducer through an ultrasonic connecting line, and the ultrasonic transducer, the ultrasonic horn and the vertical slider are connected in sequence.

[0018] Preferably, the ultrasonic transducer is connected to the ultrasonic generator via an ultrasonic connecting line, and the ultrasonic transducer is fixedly connected to the ultrasonic housing via a transducer connecting flange.

[0019] Preferably, an ultrasonic cooling air interface is provided on the ultrasonic housing for introducing compressed gas into the interior of the ultrasonic housing, and a micro-forging cooling air interface is provided on the micro-forging housing for introducing compressed gas into the interior of the micro-forging housing.

[0020] Preferably, the horizontal slider and the ultrasonic connector can generate radial relative movement, and the vertical slider and the ultrasonic connector can generate axial relative movement.

[0021] Compared with the prior art, this application has the following beneficial effects:

[0022] 1. This application combines the micro-forging system with the ultrasonic impact system through ingenious structural design, and simultaneously realizes the axial movement of the micro-forging system and the radial movement of the ultrasonic impact system, resulting in a better strengthening effect.

[0023] 2. The present application adopts a compact structural design so that the device can be directly assembled on the main shaft of the equipment, which is easy to use.

[0024] 3. This application realizes multi-degree-of-freedom movement of the punch through the coordinated design of the ultrasonic connector and the slider, which can meet various usage requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0026] Figure 1 This is a schematic diagram of the structure of the micro-forging device mainly embodied in this application;

[0027] Figure 2 This is a schematic diagram of the structure of the ultrasonic impact device mainly embodied in this application;

[0028] Figure 3 This is a schematic diagram of the overall structure of this application.

[0029] As shown in the figure: 1. Cooling air interface; 2. Micro-forging shell; 3. Bearing; 4. Cooling air interface; 5. Horizontal slider; 6. Ultrasonic connector; 7. Ultrasonic shell; 8. Spring; 9. Punch; 10. Mechanical interface; 11. Upper limit block; 12. Coil support; 13. Permanent magnet; 14. Excitation coil; 15. Circuit interface; 16. Connecting rod; 17. Transducer connecting flange; 18. Ultrasonic transducer; 19. Vertical slider; 20. Ultrasonic amplitude transformer; 21. Ultrasonic connecting line; 22. Ultrasonic generator. DETAILED DESCRIPTION

[0030] The present application is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present application, but do not limit the present application in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present application. These all belong to the protection scope of the present application.

[0031] like Figure 3 As shown, a radial ultrasonic-assisted micro-forging surface strengthening device provided by the present application includes a micro-forging system and an ultrasonic impact system. The micro-forging system generates low-frequency and large-amplitude axial motion, and the ultrasonic impact system generates high-frequency and small-amplitude radial motion.

[0032] Specifically, the device of the present application includes a micro-forging housing 2, an ultrasonic connector 6, a horizontal slider 5, a vertical slider 19, a punch 9 and a spring 8. The horizontal slider 5 is installed between the ultrasonic connector 6 and the output end of the micro-forging system, and the micro-forging system drives the ultrasonic connector 6 and the punch 9 to move axially.

[0033] The horizontal slider 5 can be installed in two ways: one end is fixedly connected to the output end of the micro-forging system, and the other end is radially displaced with the ultrasonic connector 6; or one end is fixedly connected to the ultrasonic connector 6, and the other end is radially displaced with the output end of the micro-forging system. The vertical slider is arranged between the ultrasonic connector 6 and the output end of the ultrasonic impact system, and the ultrasonic impact system drives the ultrasonic connector 6 and the punch 9 to move radially.

[0034] The vertical slider 19 can be installed in the following ways: one end moves radially relative to the ultrasonic connector 6 and the other end is fixedly connected to the ultrasonic horn 20 ; or one end is fixedly connected to the ultrasonic connector 6 and the other end moves radially relative to the ultrasonic horn 20 .

[0035] More specifically, the device of the present application also includes a connecting rod 16, a micro-forging system driving assembly, an upper limit block 11, a water ultrasonic horn 20, an ultrasonic transducer 18, a transducer connecting flange 17 and an ultrasonic generator 22. The connecting rod 16 passes through the horizontal slider 5 of the driving assembly and the ultrasonic connector 6 in sequence, and the connecting rod 16 is installed as a whole in the housing 2. The protruding part of the connecting rod 16 can be set to a threaded structure to achieve a threaded connection with the punch 9. Working principle: Because the driving assembly is fixedly connected to the connecting rod 16, when the driving assembly is started, the connecting rod 16 and the horizontal slider 5, the ultrasonic connector 6 and the punch 9 fixedly connected to the connecting rod 16 are driven to move axially, and the punch 9 realizes axial strengthening processing of the workpiece. An upper limit block 11 is provided at one end of the micro-forging housing 2 axially away from the punch, and the upper limit block 11 limits the axial displacement of the connecting rod 16.

[0036] The ultrasonic generator 22 is connected to the ultrasonic transducer 18 through the ultrasonic connecting line 21, and the ultrasonic transducer 18 is connected to the ultrasonic horn 20, the vertical slider 19, and the ultrasonic connector 6 in sequence. The principle is as follows: the electrical signal generated by the ultrasonic generator 22 is converted into mechanical vibration in the horizontal direction after passing through the ultrasonic transducer 18, and the ultrasonic horn 20 further amplifies the mechanical vibration in the horizontal direction. The amplified mechanical vibration is transmitted to the ultrasonic connector 6 through the vertical slider 19, and then the punch 9 fixedly connected to the ultrasonic connector 6 completes the output of radial motion.

[0037] This application provides a feasible embodiment: Figure 3The radial ultrasonic assisted micro-forging surface strengthening device shown includes a micro-forging shell 2, a connecting rod 16, a mechanical interface 10, an upper limit block 11, a permanent magnet 13, a coil support 12, an excitation coil 14, a bearing 3, a horizontal slider 5, a vertical slider 19, an ultrasonic shell 7, an ultrasonic transducer 18, an ultrasonic generator 22, an ultrasonic horn 20, an ultrasonic connector 6, a transducer connection flange 17, a punch 9 and a spring 8. The permanent magnet 13 is fixedly connected to the inside of the micro-forging shell 2. The excitation coil 14 is wound on the coil support 12 and fixedly connected to the connecting rod 16, and the permanent magnet 13 forms a fixed magnetic field in the micro-forging shell 2. The connecting rod 16 passes through the coil support 12 and is integrally installed in the micro-forging shell 2. The connecting rod 16 is fixedly connected to the horizontal slider 5, the ultrasonic connector 6 and the punch 9 in sequence. An ultrasonic connecting line 21 interface is provided on the ultrasonic shell 7, and the ultrasonic generator 22 is connected to the ultrasonic transducer 18 through the ultrasonic connecting line 21 interface to convert the ultrasonic signal into mechanical vibration. The ultrasonic transducer 18 is connected to the ultrasonic horn 20 to amplify the mechanical vibration. The ultrasonic horn 20 then inputs the mechanical vibration output from the previous link to the vertical slider 19. The vertical slider 19 is connected to the ultrasonic connector 6. Finally, under the action of the mechanical vibration, the punch 9 is driven to move radially.

[0038] A spring 8 is connected between the ultrasonic connector 6 and the housing 2 , and the punch 9 passes through the spring 8 to achieve reset of the punch 9 .

[0039] Working principle: the permanent magnet 13 is fixed in the shell to form a fixed magnetic field. The excitation coil 14 is wound on the coil support 12. The coil support 12 is fixedly connected to the connecting rod 16. The circuit of the excitation coil 14 can be introduced through the circuit interface 15 set on the shell 2. The connecting rod 16 and the ultrasonic connector 6 can move relative to each other in the horizontal direction through the horizontal slider 5. The excitation coil 14, the coil support 12, the connecting rod 16 and the vertical slider 19, the ultrasonic connector 6, and the punch 9 together constitute the impact mover. When current is passed through the coil, due to the principle of electromagnetic interaction, an electromagnetic field will be generated in the solid state generated by the permanent magnet 13. Under a fixed magnetic field, a corresponding electromagnetic force is generated to drive the mover to move. When an alternating current of a certain frequency is passed through the coil, an alternating electromagnetic force of the corresponding frequency is generated, thereby driving the forging head system to produce periodic motion. When the mover impacts the workpiece downward and the upper end impacts the upper limit block 11, it is subjected to a corresponding vertical reaction force. A dynamic balance is formed between the alternating electromagnetic force and the reaction force. The micro-forging head realizes reciprocating mechanical impact motion, continuously impacting the surface of the part to achieve a mechanical strengthening effect. Since the electromagnetic drive process generates heat, compressed air is introduced through the air path interface of the electromagnetic micro-forging part to realize cooling of the electromagnetic micro-forging drive system.

[0040] The ultrasonic impact system includes an ultrasonic shell 7, an ultrasonic generator 22, an ultrasonic transducer 18 and an ultrasonic horn 20. Both the ultrasonic transducer 18 and the ultrasonic horn 20 are located inside the ultrasonic shell 7. The ultrasonic generator 22 is connected to the ultrasonic transducer 18 through an ultrasonic connecting line 21. The ultrasonic transducer 18, the ultrasonic horn 20 and the vertical slider 19 are connected in sequence.

[0041] The ultrasonic generator 22 is connected to the ultrasonic transducer 18 through the ultrasonic connecting line 21. The ultrasonic transducer 18 converts the ultrasonic signal into mechanical vibration and transmits it to the ultrasonic horn 20. The ultrasonic horn 20 amplifies the mechanical vibration and outputs it to the ultrasonic connector 6. Under the action of the horizontal slider 5, the punch 9 and the horizontal slider 5 can produce radial relative motion. That is to say, the punch 9 can simultaneously realize the composite motion in the axial and radial directions through the setting of the horizontal slider 5 and the vertical slider 19.

[0042] The low-frequency large-stroke impact motion referred to in this application refers to hundreds of hertz, specifically 100HZ-999HZ, and millimeter-level stroke motion; high-frequency small-stroke impact motion refers to tens of thousands of hertz, specifically 10000HZ-99999HZ, and micrometer-level stroke motion.

[0043] In the description of the present application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0044] The above describes the specific embodiments of the present application. It should be understood that the present application is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the substantive content of the present application. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be arbitrarily combined with each other.

Claims

1. A radial ultrasonic assisted micro-forging surface strengthening device, characterized in that: include: A micro-forging system and an ultrasonic impact system, wherein the micro-forging system is used to generate low-frequency large-amplitude impact motion, and the ultrasonic impact system is used to generate high-frequency small-amplitude impact motion; The axial output generated by the micro-forging system is combined with the radial output generated by the ultrasonic impact system.

2. A radial ultrasonic assisted micro-forging surface strengthening device, characterized in that: include: A micro-forging housing (2), an ultrasonic connector (6), a horizontal slider (5), a vertical slider (19), a punch (9) and a spring (8); The horizontal slider (5) is installed between the ultrasonic connector (6) and the output end of the micro-forging system, and the micro-forging system drives the ultrasonic connector (6) and the punch (9) to move axially; The vertical slider (19) is installed between the ultrasonic connector (6) and the output end of the ultrasonic impact system, and the ultrasonic impact system drives the ultrasonic connector (6) and the punch (9) to move in the radial direction; The spring (8) is used to reset both the punch (9) and the ultrasonic connector (6).

3. The radial ultrasonic assisted micro-forging surface strengthening device according to claim 1, characterized in that: The low-frequency and large-amplitude impact motion is hundreds of hertz and millimeter-level stroke motion; The high-frequency small-amplitude impact motion is tens of thousands of hertz and micron-level stroke motion.

4. The radial ultrasonic assisted micro-forging surface strengthening device according to claim 2, characterized in that: The micro-forging system comprises a driving assembly, and the driving assembly is drivingly connected to an output shaft of the micro-forging system; The driving assembly includes a pneumatic driving assembly, a piezoelectric driving assembly or an electromagnetic driving assembly.

5. The radial ultrasonic assisted micro-forging surface strengthening device according to claim 4, characterized in that: The electromagnetic drive assembly comprises: a permanent magnet (13), a coil support (12) and an excitation coil (14), wherein the permanent magnet (13) is fixedly mounted on the micro-forging housing (2), the excitation coil (14) is wound on the coil support (12), and the excitation coil (14) is coupled to the permanent magnet (13); The coil support (12) is connected with a connecting rod (16) as an output shaft of the micro-forging system.

6. The radial ultrasonic assisted micro-forging surface strengthening device according to claim 1, characterized in that: An upper limit block (11) is provided at one end of the micro-forging housing (2) axially away from the punch, and the upper limit block (11) limits the axial displacement of the connecting rod (16); A mechanical interface (10) is provided on the top of the upper limit block (8).

7. The radial ultrasonic assisted micro-forging surface strengthening device according to claim 2, characterized in that: The ultrasonic impact system comprises an ultrasonic housing (7), an ultrasonic generator (22), an ultrasonic transducer (18) and an ultrasonic horn (20); the ultrasonic transducer (18) and the ultrasonic horn (20) are both located inside the ultrasonic housing (7); the ultrasonic generator (22) is connected to the ultrasonic transducer (18) via an ultrasonic connecting line (21); and the ultrasonic transducer (18), the ultrasonic horn (20) and the vertical slider (19) are connected in sequence.

8. The radial ultrasonic assisted micro-forging surface strengthening device according to claim 7, characterized in that: The ultrasonic transducer (18) is fixedly connected to the ultrasonic housing (7) via a transducer connecting flange (17).

9. The radial ultrasonic assisted micro-forging surface strengthening device according to claim 7, characterized in that: The ultrasonic housing (7) is provided with an ultrasonic cold air interface (4) for introducing compressed gas into the ultrasonic housing (7); The micro-forging shell (2) is provided with a micro-forging cold air interface for introducing compressed gas into the micro-forging shell (2).

10. The radial ultrasonic assisted micro-forging surface strengthening device according to claim 7, characterized in that: The horizontal slider (5) and the ultrasonic connector (6) can generate radial relative movement, and the vertical slider (19) and the ultrasonic connector (6) can generate axial relative movement.

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