Ultrasonic machining spindle

Abstract

The invention discloses an ultrasonic machining main shaft which comprises a main shaft body, a rotating shaft, an electric connector and a machining cutter handle, and the machining cutter handle is installed at one end of the rotating shaft. An ultrasonic transducer is arranged in the machining cutter handle; at least two conductive assemblies are arranged between the main shaft body and the rotating shaft, and the conductive assemblies are electrically connected with the ultrasonic transducer and the electric connector; each conductive assembly comprises a first supporting ring, a second supporting ring and a plurality of rolling bodies arranged between the first supporting ring and the second supporting ring. The rolling body is made of a non-conductive material; the sealing parts are located on the two sides of the rolling body, a containing cavity is formed between the sealing parts, and the containing cavity is filled with a conducting medium. The current conduction path is changed, and the first supporting ring and the second supporting ring are conducted by current through the conducting medium, the retaining part and the sealing part, so that the electric corrosion phenomenon of the conducting assembly is avoided, stable power supply to the ultrasonic transducer can be ensured, the machining precision of the main shaft is improved, the service life of the main shaft is prolonged, and the conducting power is improved.

Description

Technical Field

[0001] This application relates to the field of machine tool technology, specifically to an ultrasonic machining spindle. Background Technology

[0002] The ultrasonic transducer is the core component of the ultrasonic spindle system. The transducer usually uses piezoelectric ceramic material and utilizes the inverse piezoelectric effect to realize energy conversion. The transducer converts electrical energy into mechanical vibration to achieve cutting or machining of the workpiece.

[0003] The power supply spindle for an ultrasonic knife handle, disclosed in CN110170668A, includes a body, a positive terminal of the knife handle, a negative terminal of the knife handle, a knife handle wire, and a plurality of piezoelectric plates. The power supply spindle includes a housing, a rotating shaft, a first bearing, a second bearing, and an electrical connector. The housing houses a built-in high-frequency motor for driving the rotating shaft. The first bearing is fitted onto an insulating base, which is connected to the rotating shaft and rotates synchronously with it. The second bearing is fitted between the housing and the rotating shaft and electrically connected to both. The electrical connector includes a first electrode and a second electrode. The first electrode is electrically connected to the first bearing, and the second electrode is electrically connected to the housing. This design allows for the generation of an electrical connection circuit through the ultrasonic knife handle body, providing a stable power supply to the ultrasonic knife handle. This overcomes the adverse effects of conventional carbon brushes, such as reduced conductivity, short circuits, and high heat generation, caused by easy carbon buildup.

[0004] Because the ultrasonic transducer inside the tool holder is powered by bearings as conductors, when current flows through the outer ring, balls, and inner ring to supply power to the ultrasonic transducer, a voltage difference is created between the two contact surfaces inside the bearing, causing electrolytic erosion. When the voltage difference is high enough, spark discharge occurs at the two contact surfaces, generating high temperatures and causing localized surface melting, forming arc-shaped pits or grooves. This results in pits on the inner ring, outer ring, and balls, which in turn affects the power supply to the transducer, and also impacts the spindle's lifespan and machining accuracy. Summary of the Invention

[0005] To address the aforementioned problems, this application provides an ultrasonic machining spindle that uses a conductive medium to connect the first and second support rings, preventing electrolytic corrosion and ensuring stable power supply to the ultrasonic transducer. This improves the spindle's machining accuracy and service life. The technical solution is as follows: An ultrasonic machining spindle includes a spindle body, a rotating shaft, an electrical connector, and a machining tool holder, wherein the machining tool holder is mounted on one end of the rotating shaft; an ultrasonic transducer is provided inside the machining tool holder. At least two conductive components are provided between the main shaft body and the rotating shaft, as well as a drive component for driving the rotating shaft to rotate. The conductive components are electrically connected to the ultrasonic transducer and the electrical connector. Each conductive component includes a first support ring and a second support ring, and a plurality of rolling elements disposed between the first support ring and the second support ring; the rolling elements are made of non-conductive material. Sealing components are located on both sides of the rolling element, and a receiving cavity is formed between the sealing components, the receiving cavity being filled with a conductive medium; Current flows through the conductive medium to connect the first support ring and the second support ring.

[0006] Preferably, the conductive component further includes a retaining portion for separating the rolling elements. Both the retaining portion and the sealing component are conductive, and current flows through the conductive medium, the retaining portion, and the sealing component to connect the first support ring and the second support ring.

[0007] Preferably, the conductive component further includes a conductive portion disposed on the second support ring and extending toward one side of the first support ring, the conductive portion being located between the sealing components.

[0008] More preferably, the distance extended by the conductive part is L2, and the distance between the retaining part and the first support ring is L1, where L1 < L2.

[0009] Preferably, any one of the conductive components is insulated from the rotating shaft, the main shaft body, and the remaining conductive components.

[0010] Preferably, it further includes a first conductive component for electrically connecting the conductive component and the ultrasonic transducer.

[0011] More preferably, the first conductive component includes a first conductive ring insulated from the rotating shaft and a second conductive ring insulated from the machining tool holder, the first conductive ring being electrically connected to a conductive component and the second conductive ring being electrically connected to the ultrasonic transducer.

[0012] Preferably, the conductive components are all located on the side away from the machining tool holder.

[0013] Preferably, at least one first conductive component and at least one second conductive component are provided between the spindle body and the rotating shaft, and the positive terminal of the electrical connector, the first conductive component, the ultrasonic transducer, the machining tool holder, the rotating shaft, the second conductive component, and the negative terminal of the electrical connector form a connected circuit.

[0014] Compared with the prior art, the beneficial effects of this application are as follows: (1) This application uses the first support ring, the conductive medium, the holding part and the second support ring as the current conduction path to ensure that the conductive component will not experience electro-erosion, and can stably supply power to the ultrasonic transducer, improve the spindle machining accuracy and service life, and increase the conductive power.

[0015] (2) By providing a conductive part on the second guide ring, when the conductive component is working, the centrifugal force throws the conductive medium to the side of the second support ring. A gap may appear between the conductive medium and the first support ring. At this time, the conductive part can connect the first support ring and the conductive medium to avoid the current from not being able to conduct.

[0016] (3) By simultaneously working through the conductive medium, the holding part, the conductive part and the sealing part to make the first support ring and the second support ring conductive, the conductive power can be further improved.

[0017] (4) The rolling elements are made of ceramic material, which will not cause electrolytic corrosion and can greatly improve the rotation speed of the rotating shaft. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of an embodiment of this application; Figure 2 This is a front view of the conductive component of this application (the sealing component is not shown). Figure 3 This is a schematic diagram of the internal structure of a conductive component according to this application; Figure 4 This is a schematic diagram of the internal structure of another conductive component in this application; Figure 5 This application Figure 1 Enlarged view of a portion of point A in the middle; Figure 6 This is a schematic diagram of another embodiment of the present application; Figure 7 This is a schematic diagram of a processing device according to this application.

[0019] In the picture: 1. Main spindle body; 2. Rotary shaft; 3. Conductive components; 3.1 First conductive component; 3.2 Second conductive component; 31 First support ring; 32 Second support ring; 33 Rolling element; 34 Retaining part; 35 Raceway; 351 Raceway 1; 352 Raceway 2; 36 Conductive part; 37 Conductive medium; 38 Sealing component; 4. Machining device; 4.1 Machining tool holder; 4.2 Housing; 5. Ultrasonic transducer; 6. Drive assembly; 7. First conductive component; 71. First conductive ring; 72. Second conductive ring; 73. Wire one; 74. Wire two; 710. Insulating component one; 720. Insulating component two; 8. Second conducting component; 81. Transmitting coil assembly; 82. Receiving coil assembly; 9. Supporting component; 10. Receiving cavity; 11. Sealing ring one; 12. Sealing ring two. Detailed Implementation

[0020] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described in this application are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0021] Example 1 See Figures 1 to 5 Further explanation of this application: Combination Figure 1 An ultrasonic machining spindle includes a spindle body 1, a rotating shaft 2, and a machining tool holder 4.1. The machining tool holder 4.1 is mounted on one end of the rotating shaft 2. An ultrasonic transducer 5 is provided inside the machining tool holder 4.1. The machining tool holder 4.1 includes a tool holder body, a pull stud, an amplitude transformer, and a cutting tool provided on the tool holder body. A clamping mechanism (not shown) inside the rotating shaft 2 connects the tool holder body 4.1 to the rotating shaft 2 by gripping the pull stud.

[0022] At least two conductive components 3 are provided between the main shaft body 1 and the rotating shaft 2, and a driving component 6 is provided for driving the rotating shaft 2 to rotate. The conductive components 3 are electrically connected to the ultrasonic transducer 5. The ultrasonic transducer 5 includes a plurality of piezoelectric elements for converting electrical energy into mechanical vibration.

[0023] In this embodiment, at least one first conductive component 3.1 and at least one second conductive component 3.2 are provided between the spindle body 1 and the drive; the positive terminal of the electrical connector, the first conductive component 3.1, the ultrasonic transducer 5, the machining tool holder 4.1, the rotating shaft 2, the second conductive component and the negative terminal of the electrical connector form an electrical circuit.

[0024] Combination Figures 2 to 4Both the first conductive component 3.1 and the second conductive component 3.2 include a first support ring 31 and a second support ring 32, and a plurality of rolling elements 22 disposed between the first support ring 31 and the second support ring 32; wherein, the rolling elements 22 are made of non-conductive material; in this embodiment, the rolling elements 22 are ceramic balls to meet the high speed requirements.

[0025] Sealing components 38 are located on both sides of the rolling element 22, and a receiving cavity 10 is formed between the sealing components 38. The receiving cavity 10 is filled with a conductive medium 37.

[0026] When current flows through the conductive component 3, the second support ring 32 and the first support ring 31 are connected through the conductive medium 37.

[0027] Existing technology uses bearing balls as conductors to power the ultrasonic transducer 5. The current must flow sequentially through the outer ring, the balls, and the inner ring before reaching the piezoelectric element. However, this method is prone to electrolytic corrosion. This application, by changing the current flow path, directs the current sequentially through the first support ring 31, the conductive medium 37, and the second guide ring to the ultrasonic transducer 5, thus avoiding electrolytic corrosion. This ensures stable power supply to the ultrasonic transducer, guarantees spindle machining accuracy, and improves spindle lifespan.

[0028] Combination Figure 5 In this embodiment, a first conductive component 7 is also included, which is used to electrically connect the first conductive component 3.1 to the ultrasonic transducer 5.

[0029] Specifically, the first conductive component 7 includes a first conductive ring 71 that is insulated from the rotating shaft 2 and a second conductive ring 72 that is insulated from the machining tool holder 4.1. The first conductive ring 71 is electrically connected to the first conductive component 3.1 by a wire 73, and the second conductive ring 72 is electrically connected to the ultrasonic transducer 5 by a wire 74.

[0030] When the machining tool holder 4.1 is mounted on the rotating shaft 2, the first conductive ring 71 abuts against and contacts the second conductive ring 72. Both the first conductive ring 71 and the second conductive ring 72 are annular structures, with a large contact area, high power conduction, and low heat generation.

[0031] The positive terminal of the electrical connector is electrically connected to the second support ring 32 of the first conductive component 3.1 via a wire, and the negative terminal of the electrical connector is electrically connected to the spindle body 1 via a wire.

[0032] In this embodiment, an insulating component 710 is provided between the first conductive ring 71 and the rotating shaft 2, and an insulating component 720 is provided between the machining handle 4.1 and the second conductive ring 72. Both the insulating component 710 and the insulating component 720 include a fixed part, the fixed part having a "U" shaped cross-section, for placing the first conductive ring 71 and the second conductive ring 72. Movable parts extending outward are provided on both sides of the fixed part. When the machining handle 4.1 rotates, the movable part of the insulating component 720 will fit against the movable part of the insulating component 710 through centrifugal force, thus achieving a seal and preventing moisture in the external environment from affecting the first conductive component 7.

[0033] In the prior art, the bearing used for conducting electricity is located at one end of the machining tool holder 4.1. During the machining process, coolant needs to be sprayed onto the workpiece or tool for lubrication and cooling, which puts the conductor in a harsh environment. Moisture can easily corrode the conductor and cause a short circuit.

[0034] Combination Figure 1 In this embodiment, both the first conductive component 3.1 and the second conductive component 3.2 are located at the end furthest from the machining tool holder 4.1. Figure 1 (with the top of the middle section) to prevent the conductive component 3 from working in a harsh environment, thus ensuring that the conductive component 3 can work stably.

[0035] The first conductive component 3.1 is insulated from the rotating shaft 2, the main shaft body 1 and the second conductive component 3.2. They can be separated by setting insulating parts or insulating layers to avoid short circuits.

[0036] Specifically, the first support ring 31 is insulated from the rotating shaft 2 by an insulating sleeve 1, and the second support ring 32 is insulated from the main shaft body 1 by an insulating sleeve 2; the first conductive component 3.1 and the second conductive component 3.2 are separated and insulated by an insulating ring 1 sleeved on the rotating shaft 2 and an insulating ring 2 sleeved on the inner side of the main shaft body 1.

[0037] In this embodiment, one end of the sealing component 38 is connected to the second support ring 32, and the other end abuts against the first support ring 31; of course, the sealing component 38 and the first support ring 31 can be non-contact, with a certain gap, to reduce noise.

[0038] In this embodiment, the conductive component 3 further includes a retaining portion 34, which is used to separate the rolling element 22; both the retaining portion 34 and the sealing component 38 are conductive. During operation, current flows through the conductive medium 37, the sealing component 38, and the retaining portion 34 to connect the first support ring 31 and the second support ring 32, which can further improve the conductivity and increase the conductive power of the ultrasonic transducer 5.

[0039] In this embodiment, both the first support ring 31 and / or the second support ring 32 are provided with raceways 35. The raceways 35 are arranged opposite to each other and are used to restrict the rolling element 22 and guide the rolling element 22 to roll. The raceways 35 include a first raceway 351 provided on the first support ring 31 and a second raceway 352 provided on the second support ring 32.

[0040] Several supporting components 9 are also provided between the main shaft body 1 and the rotating shaft 2 to support the rotation of the rotating shaft 2; wherein, the supporting component 9 is a ceramic bearing, which, compared with traditional steel bearings, can support the high-speed rotation of the rotating shaft 2.

[0041] In this embodiment, the conductive component 3 is illustrated using a deep groove ball bearing as an example; of course, the conductive component 3 can also be other types of bearings, such as angular contact bearings or cylindrical roller bearings.

[0042] Example 2 As the conductive component 3 rotates at high speed, centrifugal force will throw the conductive medium 37 outward; that is, towards the side of the second support ring 32, the conductive medium 37 will gather on the side of the second support ring 32; at this time, there may be a gap between the conductive medium 37 and the first support ring 31, which will cause the current to be unable to be conducted to the ultrasonic transducer 5 through the conductive component 3.

[0043] Combination Figure 4 Compared with Embodiment 1, the difference in this embodiment is that the conductive component 3 further includes a conductive part 36 for connecting the first support ring 31 and the conductive medium 37. The conductive part 36 is disposed on the first support ring 31 and extends toward the second support ring 32. The conductive part 36 is located in the receiving cavity 10. When the conductive component 3 rotates at high speed, the conductive part 36 can connect the conductive medium 37 to the first support ring 31.

[0044] Wherein, the distance by which the conductive part 36 extends beyond the first support ring 31 is L2, and the distance between the holding part 34 and the first support ring 31 is L1, L1 < L2, thereby ensuring that the conductive component is always in a conductive state; in this embodiment, the holding part 34 has a ring structure, and a gap is provided between the extended end of the conductive part 36 and the second support ring 32 to avoid direct contact between the conductive part 36 and the second support ring 32, which can reduce noise.

[0045] Example 3 Based on Embodiment 1 or Embodiment 2, this embodiment further includes a second conductive component 8. The second conductive component 8 drives the ultrasonic transducer 5 via electromagnetic induction. A switching device is provided between the second conductive component 8 and the conductive component 3. The switching device is used to control the connection between the conductive component 3 or the second conductive component 8 and the ultrasonic transducer 5; wherein, the switching device can be a control switch. This avoids a single processing method, allowing the conductive component 3 and the second conductive component 8 to be used interchangeably, reducing workload, thereby increasing service life and shortening maintenance cycles.

[0046] Combination Figure 6 The second conductive component 8 includes a receiving coil component 82 and a transmitting coil component 81. The receiving coil component 82 is electrically connected to the ultrasonic transducer 5. The receiving coil component 82 is insulated from the rotating shaft 2, and the transmitting coil component 81 is insulated from the main shaft body 1.

[0047] The second conductive component 8 and the conductive component 3 are disposed at the same end to reduce the influence of impurities in the external environment on the second conductive component 8.

[0048] In this embodiment, the receiving coil assembly 82 is electrically connected to the first conducting assembly 7, and the first conducting assembly 7 is electrically connected to the ultrasonic transducer 5. Specifically, the receiving coil assembly 82 and the first conductive ring 71 are connected by three electrical wires, and the second conductive ring 72 and the ultrasonic transducer 5 are connected by four electrical wires.

[0049] When the power supply is switched to the second conductive component 3.2, the transmitting coil component 81 is powered. Through the principle of electromagnetic induction, a current is generated in the receiving coil component 82 and conducted through the third wire to the first conductive ring 71 of the first conductive component 7. Then, it is conducted through the second conductive ring 72 of the first conductive component 7 and the fourth wire to the ultrasonic transducer 5.

[0050] Example 4 Combination Figures 2 to 4 ,and Figure 7As shown, this application also provides a processing apparatus, including a processing tool holder 4.1, an electrical connector, and a housing 4.2 disposed outside the processing tool holder 4.1; the processing tool holder 4.1 is provided with a placement cavity, and the ultrasonic transducer 5 is disposed in the placement cavity; At least two conductive components 3 are provided between the machining handle 4.1 and the housing 4.2 to support the rotation of the machining handle 4.1 and to be in communication with the ultrasonic transducer 5; In this embodiment, at least one first conductive component 3.1 and at least one second conductive component 3.2 are provided between the machining tool holder 4.1 and the housing 4.2. A conductive circuit is formed by the positive terminal of the electrical connector, the first conductive component 3.1, the ultrasonic transducer 5, the machining tool holder 4.1, and the negative terminal of the electrical connector.

[0051] Both the first conductive component 3.1 and the second conductive component 3.2 include a first support ring 31 and a second support ring 32, and a plurality of rolling elements 22 disposed between the first support ring 31 and the second support ring 32. The rolling elements 22 are made of a non-conductive material; in this embodiment, the rolling elements 22 are made of ceramic material, which is suitable for high-speed machining; of course, other non-conductive materials can also be used.

[0052] The sealing components 38 are located on both sides of the rolling element 22, and a receiving cavity 10 is formed between the sealing components 38. The receiving cavity 10 is filled with the conductive medium 37.

[0053] When current passes through the conductive component 3, the first support ring 31 and the second support ring 32 are connected through the conductive medium 37.

[0054] In this embodiment, the ultrasonic transducer 5 is electrically connected to the first support ring 31 of the first conductive component 3.1, and the electrical connector is electrically connected to the second support ring 32 of the first conductive component 3.1 and the housing 42 via wires; the first support ring 31 of the second conductive component 3.2 is sleeved on the outside of the machining tool holder 4.1, and the second support ring 32 of the second conductive component 3.2 is sleeved on the inside of the housing 4.2.

[0055] Combination Figure 7 The first conductive component 3.1 is insulated from the second conductive component 3.2, the housing 4.2 and the machining tool holder 4.1.

[0056] Specifically, the first support ring 31 of the first conductive component 3.1 is insulated from the machining tool holder 4.1 by an insulating sleeve, and the second support ring 32 is insulated from the housing 4.2 by an insulating sleeve. The first conductive component 3.1 and the second conductive component 3.2 are separated and insulated by an insulating ring 1 sleeved on the machining tool holder 4.1 and an insulating ring 2 sleeved on the inner side of the housing 4.2.

[0057] To prevent external impurities from entering between the housing 4.2 and the machining tool holder 4.1, a sealing assembly is also provided between the housing 4.2 and the machining tool holder 4.1, wherein the sealing assembly includes a sealing assembly one and a sealing assembly two provided at both ends of the housing.

[0058] Both the first sealing assembly and the second sealing assembly include a first sealing ring 11 and a second sealing ring 12. The first sealing ring 11 has a protrusion, and the second sealing ring 12 has a groove that mates with the protrusion. The protrusion and the groove form a labyrinth-type sealing structure.

Claims

1. An ultrasonic machining spindle, characterized in that: It includes a spindle body, a rotary shaft, an electrical connector, and a machining tool holder, wherein the machining tool holder is mounted on one end of the rotary shaft; an ultrasonic transducer is provided inside the machining tool holder; At least two conductive components are provided between the main shaft body and the rotating shaft, as well as a drive component for driving the rotating shaft to rotate. The conductive components are electrically connected to the ultrasonic transducer and the electrical connector. Each conductive component includes a first support ring and a second support ring, and a plurality of rolling elements disposed between the first support ring and the second support ring; the rolling elements are made of non-conductive material. Sealing components are located on both sides of the rolling element, and a receiving cavity is formed between the sealing components, the receiving cavity being filled with a conductive medium; Current flows through the conductive medium to connect the first support ring and the second support ring.

2. The ultrasonic machining spindle according to claim 1, characterized in that: The conductive component further includes a retaining portion for separating the rolling elements. Both the retaining portion and the sealing component are conductive, and current flows through the conductive medium, the retaining portion, and the sealing component to connect the first support ring and the second support ring.

3. The ultrasonic machining spindle according to claim 1 or 2, characterized in that: The conductive component further includes a conductive part disposed on the second support ring and extending toward one side of the first support ring, the conductive part being located between the sealing components.

4. The ultrasonic machining spindle according to claim 3, characterized in that: The distance extended by the conductive part is L2, and the distance between the retaining part and the first support ring is L1, where L1 < L2.

5. The ultrasonic machining spindle according to claim 1, characterized in that: Each of the conductive components is insulated from the rotating shaft, the main shaft body, and the remaining conductive components.

6. The ultrasonic machining spindle according to claim 1, characterized in that: It also includes a first conductive component, which is used to electrically connect the conductive component to the ultrasonic transducer.

7. The ultrasonic machining spindle according to claim 6, characterized in that: The first conductive component includes a first conductive ring that is insulated from the rotating shaft and a second conductive ring that is insulated from the machining tool holder. The first conductive ring is electrically connected to one of the conductive components, and the second conductive ring is electrically connected to the ultrasonic transducer.

8. The ultrasonic machining spindle according to claim 1, characterized in that: All conductive components are located on the side away from the machining tool holder.

9. The ultrasonic machining spindle according to claim 1, characterized in that: At least one first conductive component and at least one second conductive component are provided between the spindle body and the rotating shaft. The positive terminal of the electrical connector, the first conductive component, the ultrasonic transducer, the machining tool holder, the rotating shaft, the second conductive component, and the negative terminal of the electrical connector form a connected circuit.

Images